diff --git a/commands/Kconfig b/commands/Kconfig index cf414200..e934f29 100644 --- a/commands/Kconfig +++ b/commands/Kconfig @@ -494,6 +494,21 @@ endmenu +menu "video command " + +if VIDEO + +config CMD_SPLASH + bool + select IMAGE_RENDERER + prompt "splash" + help + show bmp files on framebuffer devices + +endif + +endmenu + config CMD_TIMEOUT tristate prompt "timeout" @@ -557,14 +572,6 @@ depends on MODULES prompt "lsmod" -config CMD_SPLASH - bool - depends on VIDEO - select IMAGE_RENDERER - prompt "splash" - help - show bmp files on framebuffer devices - config CMD_GPIO bool depends on GENERIC_GPIO diff --git a/commands/splash.c b/commands/splash.c index f40e3e1..615b1cb 100644 --- a/commands/splash.c +++ b/commands/splash.c @@ -7,8 +7,8 @@ #include #include #include -#include -#include +#include +#include static int do_splash(int argc, char *argv[]) { diff --git a/drivers/video/sdl.c b/drivers/video/sdl.c index 5031d7a..0021a06 100644 --- a/drivers/video/sdl.c +++ b/drivers/video/sdl.c @@ -11,7 +11,7 @@ #include #include #include -#include +#include static void sdlfb_enable(struct fb_info *info) { diff --git a/include/graphic_utils.h b/include/graphic_utils.h deleted file mode 100644 index 9909b6c..0000000 --- a/include/graphic_utils.h +++ /dev/null @@ -1,17 +0,0 @@ -/* - * Copyright (C) 2012 Jean-Christophe PLAGNIOL-VILLARD - * - * GPL v2 - */ - -#ifndef __GRAPHIC_UTILS_H__ -#define __GRAPHIC_UTILS_H__ - -void rgba_blend(struct fb_info *info, void *image, void* dest, int height, - int width, int startx, int starty, bool is_rgba); -void set_pixel(struct fb_info *info, void *adr, u32 px); -void set_rgb_pixel(struct fb_info *info, void *adr, u8 r, u8 g, u8 b); -void set_rgba_pixel(struct fb_info *info, void *adr, u8 r, u8 g, u8 b, u8 a); -void memset_pixel(struct fb_info *info, void* buf, u32 color, size_t size); - -#endif /* __GRAPHIC_UTILS_H__ */ diff --git a/include/gui/graphic_utils.h b/include/gui/graphic_utils.h new file mode 100644 index 0000000..9909b6c --- /dev/null +++ b/include/gui/graphic_utils.h @@ -0,0 +1,17 @@ +/* + * Copyright (C) 2012 Jean-Christophe PLAGNIOL-VILLARD + * + * GPL v2 + */ + +#ifndef __GRAPHIC_UTILS_H__ +#define __GRAPHIC_UTILS_H__ + +void rgba_blend(struct fb_info *info, void *image, void* dest, int height, + int width, int startx, int starty, bool is_rgba); +void set_pixel(struct fb_info *info, void *adr, u32 px); +void set_rgb_pixel(struct fb_info *info, void *adr, u8 r, u8 g, u8 b); +void set_rgba_pixel(struct fb_info *info, void *adr, u8 r, u8 g, u8 b, u8 a); +void memset_pixel(struct fb_info *info, void* buf, u32 color, size_t size); + +#endif /* __GRAPHIC_UTILS_H__ */ diff --git a/include/gui/image.h b/include/gui/image.h new file mode 100644 index 0000000..ea423b2 --- /dev/null +++ b/include/gui/image.h @@ -0,0 +1,20 @@ +/* + * Copyright (C) 2012 Jean-Christophe PLAGNIOL-VILLARD + * + * GPL v2 + */ + +#ifndef __GUI_IMAGE_H__ +#define __GUI_IMAGE_H__ + +struct image_renderer; + +struct image { + void *data; + struct image_renderer *ir; + int height; + int width; + int bits_per_pixel; +}; + +#endif /* __IMAGE_RENDERER_H__ */ diff --git a/include/gui/image_renderer.h b/include/gui/image_renderer.h new file mode 100644 index 0000000..5ee9969 --- /dev/null +++ b/include/gui/image_renderer.h @@ -0,0 +1,78 @@ +/* + * Copyright (C) 2012 Jean-Christophe PLAGNIOL-VILLARD + * + * GPL v2 + */ + +#ifndef __IMAGE_RENDER_H__ +#define __IMAGE_RENDER_H__ + +#include +#include +#include +#include +#include +#include + +struct image_renderer { + enum filetype type; + struct image *(*open)(char *data, int size); + void (*close)(struct image *img); + int (*renderer)(struct fb_info *info, struct image *img, void* fb, + int startx, int starty, void* offscreenbuf); + + /* + * do not free the data read from the file + * needed by bmp support + */ + int keep_file_data; + + struct list_head list; +}; + +#ifdef CONFIG_IMAGE_RENDERER +int image_renderer_register(struct image_renderer *ir); +void image_render_unregister(struct image_renderer *ir); + +int image_renderer_image(struct fb_info *info, struct image *img, void* fb, + int startx, int starty, void* offscreenbuf); + +struct image *image_renderer_open(const char* file); +void image_renderer_close(struct image *img); + +#else +static inline int image_renderer_register(struct image_renderer *ir) +{ + return -EINVAL; +} +static inline void image_renderer_unregister(struct image_renderer *ir) {} + +static inline struct image *image_renderer_open(const char* file) +{ + return ERR_PTR(-EINVAL); +} + +static inline void image_renderer_close(struct image *img) {} + +int image_renderer_image(struct fb_info *info, struct image *img, void* fb, + int startx, int starty, void* offscreenbuf); +#endif + +static inline int image_renderer_file(struct fb_info *info, const char* file, void* fb, + int startx, int starty, void* offscreenbuf) +{ + struct image* img = image_renderer_open(file); + int ret; + + if (IS_ERR(img)) + return PTR_ERR(img); + + ret = image_renderer_image(info, img, fb, startx, starty, + offscreenbuf); + + image_renderer_close(img); + + return ret; +} + +#endif /* __IMAGE_RENDERER_H__ */ diff --git a/include/image_renderer.h b/include/image_renderer.h deleted file mode 100644 index 0b686e1..0000000 --- a/include/image_renderer.h +++ /dev/null @@ -1,85 +0,0 @@ -/* - * Copyright (C) 2012 Jean-Christophe PLAGNIOL-VILLARD - * - * GPL v2 - */ - -#ifndef __IMAGE_RENDER_H__ -#define __IMAGE_RENDER_H__ - -#include -#include -#include -#include -#include - -struct image { - void *data; - struct image_renderer *ir; - int height; - int width; - int bits_per_pixel; -}; - -struct image_renderer { - enum filetype type; - struct image *(*open)(char *data, int size); - void (*close)(struct image *img); - int (*renderer)(struct fb_info *info, struct image *img, void* fb, - int startx, int starty, void* offscreenbuf); - - /* - * do not free the data read from the file - * needed by bmp support - */ - int keep_file_data; - - struct list_head list; -}; - -#ifdef CONFIG_IMAGE_RENDERER -int image_renderer_register(struct image_renderer *ir); -void image_render_unregister(struct image_renderer *ir); - -int image_renderer_image(struct fb_info *info, struct image *img, void* fb, - int startx, int starty, void* offscreenbuf); - -struct image *image_renderer_open(const char* file); -void image_renderer_close(struct image *img); - -#else -static inline int image_renderer_register(struct image_renderer *ir) -{ - return -EINVAL; -} -static inline void image_renderer_unregister(struct image_renderer *ir) {} - -static inline struct image *image_renderer_open(const char* file) -{ - return ERR_PTR(-EINVAL); -} - -static inline void image_renderer_close(struct image *img) {} - -int image_renderer_image(struct fb_info *info, struct image *img, void* fb, - int startx, int starty, void* offscreenbuf); -#endif - -static inline int image_renderer_file(struct fb_info *info, const char* file, void* fb, - int startx, int starty, void* offscreenbuf) -{ - struct image* img = image_renderer_open(file); - int ret; - - if (IS_ERR(img)) - return PTR_ERR(img); - - ret = image_renderer_image(info, img, fb, startx, starty, - offscreenbuf); - - image_renderer_close(img); - - return ret; -} - -#endif /* __IMAGE_RENDERER_H__ */ diff --git a/lib/Kconfig b/lib/Kconfig index 8b73733..9882d2d 100644 --- a/lib/Kconfig +++ b/lib/Kconfig @@ -38,40 +38,6 @@ config QSORT bool -config IMAGE_RENDERER - bool - depends on VIDEO - select FILETYPE - -if IMAGE_RENDERER - -config BMP - bool "bmp" - -config PNG - bool "png" - select ZLIB - -if PNG - -choice - prompt "PNG Lib" - -config LODEPNG - bool "lodePNG" - help - This PNG library supports most PNG formats. - -config PICOPNG - bool "picoPNG" - help - This PNG library only supports RGBA PNG8 but is much smaller - in binary size than lodepng. - -endchoice - -endif - -endif +source lib/gui/Kconfig endmenu diff --git a/lib/Makefile b/lib/Makefile index 7bce0e5..41e6a0f 100644 --- a/lib/Makefile +++ b/lib/Makefile @@ -34,8 +34,4 @@ obj-$(CONFIG_BCH) += bch.o obj-$(CONFIG_BITREV) += bitrev.o obj-$(CONFIG_QSORT) += qsort.o -obj-$(CONFIG_BMP) += bmp.o -obj-$(CONFIG_IMAGE_RENDERER) += image_renderer.o graphic_utils.o -obj-$(CONFIG_PNG) += png.o -obj-$(CONFIG_LODEPNG) += png_lode.o lodepng.o -obj-$(CONFIG_PICOPNG) += png_pico.o picopng.o +obj-y += gui/ diff --git a/lib/bmp.c b/lib/bmp.c deleted file mode 100644 index f5c1961..0000000 --- a/lib/bmp.c +++ /dev/null @@ -1,134 +0,0 @@ -#include -#include -#include -#include -#include "bmp_layout.h" -#include -#include -#include -#include - -struct image *bmp_open(char *inbuf, int insize) -{ - struct image *img = calloc(1, sizeof(struct image)); - struct bmp_image *bmp = (struct bmp_image*)inbuf; - - if (!img) { - free(bmp); - return ERR_PTR(-ENOMEM); - } - - img->data = inbuf; - img->height = le32_to_cpu(bmp->header.height);; - img->width = le32_to_cpu(bmp->header.width);; - img->bits_per_pixel = le16_to_cpu(bmp->header.bit_count); - - pr_debug("bmp: %d x %d x %d data@0x%p\n", img->width, img->height, - img->bit_per_pixel, img->data); - - return img; -} - -void bmp_close(struct image *img) -{ - free(img->data); -} - -static int bmp_renderer(struct fb_info *info, struct image *img, void* fb, - int startx, int starty, void* offscreenbuf) -{ - struct bmp_image *bmp = img->data; - int width, height; - int bits_per_pixel, fbsize; - void *adr, *buf; - char *image; - int xres, yres; - - xres = info->xres; - yres = info->yres; - - if (startx < 0) { - startx = (xres - img->width) / 2; - if (startx < 0) - startx = 0; - } - - if (starty < 0) { - starty = (yres - img->height) / 2; - if (starty < 0) - starty = 0; - } - - width = min(img->width, xres - startx); - height = min(img->height, yres - starty); - - bits_per_pixel = img->bits_per_pixel; - fbsize = xres * yres * (info->bits_per_pixel >> 3); - - buf = offscreenbuf ? offscreenbuf : fb; - - if (bits_per_pixel == 8) { - int x, y; - struct bmp_color_table_entry *color_table = bmp->color_table; - - for (y = 0; y < height; y++) { - image = (char *)bmp + - le32_to_cpu(bmp->header.data_offset); - image += (img->height - y - 1) * img->width * (bits_per_pixel >> 3); - adr = buf + ((y + starty) * xres + startx) * - (info->bits_per_pixel >> 3); - for (x = 0; x < width; x++) { - int pixel; - - pixel = *image; - - set_rgb_pixel(info, adr, color_table[pixel].red, - color_table[pixel].green, - color_table[pixel].blue); - adr += info->bits_per_pixel >> 3; - - image += bits_per_pixel >> 3; - } - } - } else if (bits_per_pixel == 24) { - int x, y; - - for (y = 0; y < height; y++) { - image = (char *)bmp + - le32_to_cpu(bmp->header.data_offset); - image += (img->height - y - 1) * img->width * (bits_per_pixel >> 3); - adr = buf + ((y + starty) * xres + startx) * - (info->bits_per_pixel >> 3); - for (x = 0; x < width; x++) { - char *pixel; - - pixel = image; - - set_rgb_pixel(info, adr, pixel[2], pixel[1], - pixel[0]); - adr += info->bits_per_pixel >> 3; - - image += bits_per_pixel >> 3; - } - } - } else - printf("bmp: illegal bits per pixel value: %d\n", bits_per_pixel); - - if (offscreenbuf) - memcpy(fb, offscreenbuf, fbsize); - - return img->height; -} - -static struct image_renderer bmp = { - .type = filetype_bmp, - .open = bmp_open, - .close = bmp_close, - .renderer = bmp_renderer, -}; - -static int bmp_init(void) -{ - return image_renderer_register(&bmp); -} -fs_initcall(bmp_init); diff --git a/lib/bmp_layout.h b/lib/bmp_layout.h deleted file mode 100644 index d7db537..0000000 --- a/lib/bmp_layout.h +++ /dev/null @@ -1,84 +0,0 @@ -/* (C) Copyright 2002 - * Detlev Zundel, DENX Software Engineering, dzu@denx.de. - * - * See file CREDITS for list of people who contributed to this - * project. - * - * This program is free software; you can redistribute it and/or - * modify it under the terms of the GNU General Public License as - * published by the Free Software Foundation; either version 2 of - * the License, or (at your option) any later version. - * - * This program is distributed in the hope that it will be useful, - * but WITHOUT ANY WARRANTY; without even the implied warranty of - * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the - * GNU General Public License for more details. - * - */ - -/************************************************************************/ -/* ** Layout of a bmp file */ -/************************************************************************/ - -#ifndef _BMP_H_ -#define _BMP_H_ - -struct bmp_color_table_entry { - __u8 blue; - __u8 green; - __u8 red; - __u8 reserved; -} __attribute__ ((packed)); - -/* When accessing these fields, remember that they are stored in little - endian format, so use linux macros, e.g. le32_to_cpu(width) */ - -struct bmp_header { - /* Header */ - char signature[2]; - __u32 file_size; - __u32 reserved; - __u32 data_offset; - /* InfoHeader */ - __u32 size; - __u32 width; - __u32 height; - __u16 planes; - __u16 bit_count; - __u32 compression; - __u32 image_size; - __u32 x_pixels_per_m; - __u32 y_pixels_per_m; - __u32 colors_used; - __u32 colors_important; - /* ColorTable */ - -} __attribute__ ((packed)); - -struct bmp_image { - struct bmp_header header; - /* We use a zero sized array just as a placeholder for variable - sized array */ - struct bmp_color_table_entry color_table[0]; -}; - -/* Data in the bmp_image is aligned to this length */ -#define BMP_DATA_ALIGN 4 - -/* Constants for the compression field */ -#define BMP_BI_RGB 0 -#define BMP_BI_RLE8 1 -#define BMP_BI_RLE4 2 - -#ifdef CONFIG_BMP -int bmp_render_file(struct fb_info *info, const char* bmpfile, void* fb, - int startx, int starty, int xres, int yres, void* offscreenbuf); -#else -static inline int bmp_render_file(struct fb_info *info, const char* bmpfile, void* fb, - int startx, int starty, int xres, int yres, void* offscreenbuf) -{ - return -ENOSYS; -} -#endif - -#endif /* _BMP_H_ */ diff --git a/lib/graphic_utils.c b/lib/graphic_utils.c deleted file mode 100644 index a435bdd..0000000 --- a/lib/graphic_utils.c +++ /dev/null @@ -1,191 +0,0 @@ -#include -#include -#include - -static u32 get_pixel(struct fb_info *info, u32 color) -{ - u32 px; - u8 t = (color >> 24) & 0xff; - u8 r = (color >> 16) & 0xff; - u8 g = (color >> 8 ) & 0xff; - u8 b = (color >> 0 ) & 0xff; - - if (info->grayscale) { - px = (r | g | b) ? 0xffffffff : 0x0; - return px; - } - - px = (t >> (8 - info->transp.length)) << info->transp.offset | - (r >> (8 - info->red.length)) << info->red.offset | - (g >> (8 - info->green.length)) << info->green.offset | - (b >> (8 - info->blue.length)) << info->blue.offset; - - return px; -} - -static void memsetw(void *s, u16 c, size_t n) -{ - size_t i; - u16* tmp = s; - - for (i = 0; i < n; i++) - *tmp++ = c; -} - -static void memsetl(void *s, u32 c, size_t n) -{ - size_t i; - u32* tmp = s; - - for (i = 0; i < n; i++) - *tmp++ = c; -} - -void memset_pixel(struct fb_info *info, void* buf, u32 color, size_t size) -{ - u32 px; - u8 *screen = buf; - - px = get_pixel(info, color); - - switch (info->bits_per_pixel) { - case 8: - memset(screen, (uint8_t)px, size); - break; - case 16: - memsetw(screen, (uint16_t)px, size); - break; - case 32: - case 24: - memsetl(screen, px, size); - break; - } -} - -static void get_rgb_pixel(struct fb_info *info, void *adr, u8 *r ,u8 *g, u8 *b) -{ - u32 px; - u32 rmask, gmask, bmask; - - switch (info->bits_per_pixel) { - case 16: - px = *(u16 *)adr; - break; - case 32: - px = *(u32 *)adr; - break; - case 8: - default: - return; - } - - rmask = (0xff >> (8 - info->blue.length)) << info->blue.offset | - (0xff >> (8 - info->green.length)) << info->green.offset; - - gmask = (0xff >> (8 - info->red.length)) << info->red.offset | - (0xff >> (8 - info->blue.length)) << info->blue.offset; - - bmask = (0xff >> (8 - info->red.length)) << info->red.offset | - (0xff >> (8 - info->green.length)) << info->green.offset; - - *r = ((px & ~rmask) >> info->red.offset) << (8 - info->red.length); - *g = ((px & ~gmask) >> info->green.offset) << (8 - info->green.length); - *b = ((px & ~bmask) >> info->blue.offset) << (8 - info->blue.length); -} - -void set_pixel(struct fb_info *info, void *adr, u32 px) -{ - switch (info->bits_per_pixel) { - case 8: - break; - case 16: - *(u16 *)adr = px; - break; - case 32: - *(u32 *)adr = px; - break; - } -} - -void set_rgb_pixel(struct fb_info *info, void *adr, u8 r, u8 g, u8 b) -{ - u32 px; - - px = (r >> (8 - info->red.length)) << info->red.offset | - (g >> (8 - info->green.length)) << info->green.offset | - (b >> (8 - info->blue.length)) << info->blue.offset; - - set_pixel(info, adr, px); -} - -static u8 alpha_mux(int s, int d, int a) -{ - return (d * a + s * (255 - a)) >> 8; -} - -void set_rgba_pixel(struct fb_info *info, void *adr, u8 r, u8 g, u8 b, u8 a) -{ - u32 px = 0x0; - - if (!a) - return; - - if (a != 0xff) { - if (info->transp.length) { - px |= (a >> (8 - info->transp.length)) << info->transp.offset; - } else { - u8 sr = 0; - u8 sg = 0; - u8 sb = 0; - - get_rgb_pixel(info, adr, &sr, &sg, &sb); - - r = alpha_mux(sr, r, a); - g = alpha_mux(sg, g, a); - b = alpha_mux(sb, b, a); - - set_rgb_pixel(info, adr, r, g, b); - - return; - } - } - - px |= (r >> (8 - info->red.length)) << info->red.offset | - (g >> (8 - info->green.length)) << info->green.offset | - (b >> (8 - info->blue.length)) << info->blue.offset; - - set_pixel(info, adr, px); -} - -void rgba_blend(struct fb_info *info, void *image, void* buf, int height, - int width, int startx, int starty, bool is_rgba) -{ - unsigned char *adr; - int x, y; - int xres; - int img_byte_per_pixel = 3; - - if (is_rgba) - img_byte_per_pixel++; - - xres = info->xres; - - for (y = 0; y < height; y++) { - adr = buf + ((y + starty) * xres + startx) * - (info->bits_per_pixel >> 3); - - for (x = 0; x < width; x++) { - char *pixel; - - pixel = image; - if (is_rgba) - set_rgba_pixel(info, adr, pixel[0], pixel[1], - pixel[2], pixel[3]); - else - set_rgb_pixel(info, adr, pixel[0], pixel[1], - pixel[2]); - adr += info->bits_per_pixel >> 3; - image += img_byte_per_pixel; - } - } -} diff --git a/lib/gui/Kconfig b/lib/gui/Kconfig new file mode 100644 index 0000000..8fd12fb --- /dev/null +++ b/lib/gui/Kconfig @@ -0,0 +1,39 @@ +menu "Library gui routines " + +config IMAGE_RENDERER + bool + depends on VIDEO + select FILETYPE + +if IMAGE_RENDERER + +config BMP + bool "bmp" + +config PNG + bool "png" + select ZLIB + +if PNG + +choice + prompt "PNG Lib" + +config LODEPNG + bool "lodePNG" + help + This PNG library supports most PNG formats. + +config PICOPNG + bool "picoPNG" + help + This PNG library only supports RGBA PNG8 but is much smaller + in binary size than lodepng. + +endchoice + +endif + +endif + +endmenu diff --git a/lib/gui/Makefile b/lib/gui/Makefile new file mode 100644 index 0000000..d4b26c4 --- /dev/null +++ b/lib/gui/Makefile @@ -0,0 +1,5 @@ +obj-$(CONFIG_BMP) += bmp.o +obj-$(CONFIG_IMAGE_RENDERER) += image_renderer.o graphic_utils.o +obj-$(CONFIG_PNG) += png.o +obj-$(CONFIG_LODEPNG) += png_lode.o lodepng.o +obj-$(CONFIG_PICOPNG) += png_pico.o picopng.o diff --git a/lib/gui/bmp.c b/lib/gui/bmp.c new file mode 100644 index 0000000..86591ed --- /dev/null +++ b/lib/gui/bmp.c @@ -0,0 +1,134 @@ +#include +#include +#include +#include +#include "bmp_layout.h" +#include +#include +#include +#include + +struct image *bmp_open(char *inbuf, int insize) +{ + struct image *img = calloc(1, sizeof(struct image)); + struct bmp_image *bmp = (struct bmp_image*)inbuf; + + if (!img) { + free(bmp); + return ERR_PTR(-ENOMEM); + } + + img->data = inbuf; + img->height = le32_to_cpu(bmp->header.height);; + img->width = le32_to_cpu(bmp->header.width);; + img->bits_per_pixel = le16_to_cpu(bmp->header.bit_count); + + pr_debug("bmp: %d x %d x %d data@0x%p\n", img->width, img->height, + img->bit_per_pixel, img->data); + + return img; +} + +void bmp_close(struct image *img) +{ + free(img->data); +} + +static int bmp_renderer(struct fb_info *info, struct image *img, void* fb, + int startx, int starty, void* offscreenbuf) +{ + struct bmp_image *bmp = img->data; + int width, height; + int bits_per_pixel, fbsize; + void *adr, *buf; + char *image; + int xres, yres; + + xres = info->xres; + yres = info->yres; + + if (startx < 0) { + startx = (xres - img->width) / 2; + if (startx < 0) + startx = 0; + } + + if (starty < 0) { + starty = (yres - img->height) / 2; + if (starty < 0) + starty = 0; + } + + width = min(img->width, xres - startx); + height = min(img->height, yres - starty); + + bits_per_pixel = img->bits_per_pixel; + fbsize = xres * yres * (info->bits_per_pixel >> 3); + + buf = offscreenbuf ? offscreenbuf : fb; + + if (bits_per_pixel == 8) { + int x, y; + struct bmp_color_table_entry *color_table = bmp->color_table; + + for (y = 0; y < height; y++) { + image = (char *)bmp + + le32_to_cpu(bmp->header.data_offset); + image += (img->height - y - 1) * img->width * (bits_per_pixel >> 3); + adr = buf + ((y + starty) * xres + startx) * + (info->bits_per_pixel >> 3); + for (x = 0; x < width; x++) { + int pixel; + + pixel = *image; + + set_rgb_pixel(info, adr, color_table[pixel].red, + color_table[pixel].green, + color_table[pixel].blue); + adr += info->bits_per_pixel >> 3; + + image += bits_per_pixel >> 3; + } + } + } else if (bits_per_pixel == 24) { + int x, y; + + for (y = 0; y < height; y++) { + image = (char *)bmp + + le32_to_cpu(bmp->header.data_offset); + image += (img->height - y - 1) * img->width * (bits_per_pixel >> 3); + adr = buf + ((y + starty) * xres + startx) * + (info->bits_per_pixel >> 3); + for (x = 0; x < width; x++) { + char *pixel; + + pixel = image; + + set_rgb_pixel(info, adr, pixel[2], pixel[1], + pixel[0]); + adr += info->bits_per_pixel >> 3; + + image += bits_per_pixel >> 3; + } + } + } else + printf("bmp: illegal bits per pixel value: %d\n", bits_per_pixel); + + if (offscreenbuf) + memcpy(fb, offscreenbuf, fbsize); + + return img->height; +} + +static struct image_renderer bmp = { + .type = filetype_bmp, + .open = bmp_open, + .close = bmp_close, + .renderer = bmp_renderer, +}; + +static int bmp_init(void) +{ + return image_renderer_register(&bmp); +} +fs_initcall(bmp_init); diff --git a/lib/gui/bmp_layout.h b/lib/gui/bmp_layout.h new file mode 100644 index 0000000..d7db537 --- /dev/null +++ b/lib/gui/bmp_layout.h @@ -0,0 +1,84 @@ +/* (C) Copyright 2002 + * Detlev Zundel, DENX Software Engineering, dzu@denx.de. + * + * See file CREDITS for list of people who contributed to this + * project. + * + * This program is free software; you can redistribute it and/or + * modify it under the terms of the GNU General Public License as + * published by the Free Software Foundation; either version 2 of + * the License, or (at your option) any later version. + * + * This program is distributed in the hope that it will be useful, + * but WITHOUT ANY WARRANTY; without even the implied warranty of + * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the + * GNU General Public License for more details. + * + */ + +/************************************************************************/ +/* ** Layout of a bmp file */ +/************************************************************************/ + +#ifndef _BMP_H_ +#define _BMP_H_ + +struct bmp_color_table_entry { + __u8 blue; + __u8 green; + __u8 red; + __u8 reserved; +} __attribute__ ((packed)); + +/* When accessing these fields, remember that they are stored in little + endian format, so use linux macros, e.g. le32_to_cpu(width) */ + +struct bmp_header { + /* Header */ + char signature[2]; + __u32 file_size; + __u32 reserved; + __u32 data_offset; + /* InfoHeader */ + __u32 size; + __u32 width; + __u32 height; + __u16 planes; + __u16 bit_count; + __u32 compression; + __u32 image_size; + __u32 x_pixels_per_m; + __u32 y_pixels_per_m; + __u32 colors_used; + __u32 colors_important; + /* ColorTable */ + +} __attribute__ ((packed)); + +struct bmp_image { + struct bmp_header header; + /* We use a zero sized array just as a placeholder for variable + sized array */ + struct bmp_color_table_entry color_table[0]; +}; + +/* Data in the bmp_image is aligned to this length */ +#define BMP_DATA_ALIGN 4 + +/* Constants for the compression field */ +#define BMP_BI_RGB 0 +#define BMP_BI_RLE8 1 +#define BMP_BI_RLE4 2 + +#ifdef CONFIG_BMP +int bmp_render_file(struct fb_info *info, const char* bmpfile, void* fb, + int startx, int starty, int xres, int yres, void* offscreenbuf); +#else +static inline int bmp_render_file(struct fb_info *info, const char* bmpfile, void* fb, + int startx, int starty, int xres, int yres, void* offscreenbuf) +{ + return -ENOSYS; +} +#endif + +#endif /* _BMP_H_ */ diff --git a/lib/gui/graphic_utils.c b/lib/gui/graphic_utils.c new file mode 100644 index 0000000..bf42103 --- /dev/null +++ b/lib/gui/graphic_utils.c @@ -0,0 +1,191 @@ +#include +#include +#include + +static u32 get_pixel(struct fb_info *info, u32 color) +{ + u32 px; + u8 t = (color >> 24) & 0xff; + u8 r = (color >> 16) & 0xff; + u8 g = (color >> 8 ) & 0xff; + u8 b = (color >> 0 ) & 0xff; + + if (info->grayscale) { + px = (r | g | b) ? 0xffffffff : 0x0; + return px; + } + + px = (t >> (8 - info->transp.length)) << info->transp.offset | + (r >> (8 - info->red.length)) << info->red.offset | + (g >> (8 - info->green.length)) << info->green.offset | + (b >> (8 - info->blue.length)) << info->blue.offset; + + return px; +} + +static void memsetw(void *s, u16 c, size_t n) +{ + size_t i; + u16* tmp = s; + + for (i = 0; i < n; i++) + *tmp++ = c; +} + +static void memsetl(void *s, u32 c, size_t n) +{ + size_t i; + u32* tmp = s; + + for (i = 0; i < n; i++) + *tmp++ = c; +} + +void memset_pixel(struct fb_info *info, void* buf, u32 color, size_t size) +{ + u32 px; + u8 *screen = buf; + + px = get_pixel(info, color); + + switch (info->bits_per_pixel) { + case 8: + memset(screen, (uint8_t)px, size); + break; + case 16: + memsetw(screen, (uint16_t)px, size); + break; + case 32: + case 24: + memsetl(screen, px, size); + break; + } +} + +static void get_rgb_pixel(struct fb_info *info, void *adr, u8 *r ,u8 *g, u8 *b) +{ + u32 px; + u32 rmask, gmask, bmask; + + switch (info->bits_per_pixel) { + case 16: + px = *(u16 *)adr; + break; + case 32: + px = *(u32 *)adr; + break; + case 8: + default: + return; + } + + rmask = (0xff >> (8 - info->blue.length)) << info->blue.offset | + (0xff >> (8 - info->green.length)) << info->green.offset; + + gmask = (0xff >> (8 - info->red.length)) << info->red.offset | + (0xff >> (8 - info->blue.length)) << info->blue.offset; + + bmask = (0xff >> (8 - info->red.length)) << info->red.offset | + (0xff >> (8 - info->green.length)) << info->green.offset; + + *r = ((px & ~rmask) >> info->red.offset) << (8 - info->red.length); + *g = ((px & ~gmask) >> info->green.offset) << (8 - info->green.length); + *b = ((px & ~bmask) >> info->blue.offset) << (8 - info->blue.length); +} + +void set_pixel(struct fb_info *info, void *adr, u32 px) +{ + switch (info->bits_per_pixel) { + case 8: + break; + case 16: + *(u16 *)adr = px; + break; + case 32: + *(u32 *)adr = px; + break; + } +} + +void set_rgb_pixel(struct fb_info *info, void *adr, u8 r, u8 g, u8 b) +{ + u32 px; + + px = (r >> (8 - info->red.length)) << info->red.offset | + (g >> (8 - info->green.length)) << info->green.offset | + (b >> (8 - info->blue.length)) << info->blue.offset; + + set_pixel(info, adr, px); +} + +static u8 alpha_mux(int s, int d, int a) +{ + return (d * a + s * (255 - a)) >> 8; +} + +void set_rgba_pixel(struct fb_info *info, void *adr, u8 r, u8 g, u8 b, u8 a) +{ + u32 px = 0x0; + + if (!a) + return; + + if (a != 0xff) { + if (info->transp.length) { + px |= (a >> (8 - info->transp.length)) << info->transp.offset; + } else { + u8 sr = 0; + u8 sg = 0; + u8 sb = 0; + + get_rgb_pixel(info, adr, &sr, &sg, &sb); + + r = alpha_mux(sr, r, a); + g = alpha_mux(sg, g, a); + b = alpha_mux(sb, b, a); + + set_rgb_pixel(info, adr, r, g, b); + + return; + } + } + + px |= (r >> (8 - info->red.length)) << info->red.offset | + (g >> (8 - info->green.length)) << info->green.offset | + (b >> (8 - info->blue.length)) << info->blue.offset; + + set_pixel(info, adr, px); +} + +void rgba_blend(struct fb_info *info, void *image, void* buf, int height, + int width, int startx, int starty, bool is_rgba) +{ + unsigned char *adr; + int x, y; + int xres; + int img_byte_per_pixel = 3; + + if (is_rgba) + img_byte_per_pixel++; + + xres = info->xres; + + for (y = 0; y < height; y++) { + adr = buf + ((y + starty) * xres + startx) * + (info->bits_per_pixel >> 3); + + for (x = 0; x < width; x++) { + char *pixel; + + pixel = image; + if (is_rgba) + set_rgba_pixel(info, adr, pixel[0], pixel[1], + pixel[2], pixel[3]); + else + set_rgb_pixel(info, adr, pixel[0], pixel[1], + pixel[2]); + adr += info->bits_per_pixel >> 3; + image += img_byte_per_pixel; + } + } +} diff --git a/lib/gui/image_renderer.c b/lib/gui/image_renderer.c new file mode 100644 index 0000000..99e4335 --- /dev/null +++ b/lib/gui/image_renderer.c @@ -0,0 +1,96 @@ +/* + * Copyright (C) 2012 Jean-Christophe PLAGNIOL-VILLARD + * + * GPL v2 + */ + +#include +#include +#include +#include +#include +#include + +static LIST_HEAD(image_renderers); + +static struct image_renderer *get_renderer(void* buf) +{ + struct image_renderer *ir; + enum filetype type = file_detect_type(buf); + + list_for_each_entry(ir, &image_renderers, list) { + if (ir->type == type) + return ir; + } + + return NULL; +} + +struct image *image_renderer_open(const char* file) +{ + void *data; + size_t size; + struct image_renderer *ir; + struct image *img; + int ret; + + data = read_file(file, &size); + if (!data) { + printf("unable to read %s\n", file); + return ERR_PTR(-ENOMEM); + } + + ir = get_renderer(data); + if (!ir) { + ret = -ENOENT; + goto out; + } + + img = ir->open(data, size); + if (IS_ERR(img)) { + ret = PTR_ERR(img); + goto out; + } + img->ir = ir; + if (!ir->keep_file_data) + free(data); + + return img; +out: + free(data); + return ERR_PTR(ret); +} + +void image_renderer_close(struct image *img) +{ + if (!img) + return; + + img->ir->close(img); + + free(img); +} + +int image_renderer_image(struct fb_info *info, struct image *img, void* fb, + int startx, int starty, void* offscreenbuf) +{ + return img->ir->renderer(info, img, fb, startx, starty, offscreenbuf); +} + +int image_renderer_register(struct image_renderer *ir) +{ + if (!ir || !ir->type || !ir->renderer || !ir->open || !ir->close) + return -EIO; + + list_add_tail(&ir->list, &image_renderers); + + return 0; +} + +void image_renderer_unregister(struct image_renderer *ir) +{ + if (!ir) + return; + + list_del(&ir->list); +} diff --git a/lib/gui/lodepng.c b/lib/gui/lodepng.c new file mode 100644 index 0000000..ba21cd2 --- /dev/null +++ b/lib/gui/lodepng.c @@ -0,0 +1,5928 @@ +/* +LodePNG version 20120729 + +Copyright (c) 2005-2012 Lode Vandevenne + +This software is provided 'as-is', without any express or implied +warranty. In no event will the authors be held liable for any damages +arising from the use of this software. + +Permission is granted to anyone to use this software for any purpose, +including commercial applications, and to alter it and redistribute it +freely, subject to the following restrictions: + + 1. The origin of this software must not be misrepresented; you must not + claim that you wrote the original software. If you use this software + in a product, an acknowledgment in the product documentation would be + appreciated but is not required. + + 2. Altered source versions must be plainly marked as such, and must not be + misrepresented as being the original software. + + 3. This notice may not be removed or altered from any source + distribution. +*/ + +/* +The manual and changelog are in the header file "lodepng.h" +Rename this file to lodepng.cpp to use it for C++, or to lodepng.c to use it for C. +*/ + +#include "lodepng.h" + +#include +#include + +#ifdef __BAREBOX__ +#include +#include +#include +#include +#endif + +#ifdef LODEPNG_COMPILE_CPP +#include +#endif /*LODEPNG_COMPILE_CPP*/ + +#define VERSION_STRING "20120729" + +/* +This source file is built up in the following large parts. The code sections +with the "LODEPNG_COMPILE_" #defines divide this up further in an intermixed way. +-Tools for C and common code for PNG and Zlib +-C Code for Zlib (huffman, deflate, ...) +-C Code for PNG (file format chunks, adam7, PNG filters, color conversions, ...) +-The C++ wrapper around all of the above +*/ + +/*The malloc, realloc and free functions defined here with "my" in front of the +name, so that you can easily change them to others related to your platform in +this one location if needed. Everything else in the code calls these.*/ + +static void* mymalloc(size_t size) +{ + return malloc(size); +} + +static void* myrealloc(void* ptr, size_t new_size) +{ + return realloc(ptr, new_size); +} + +static void myfree(void* ptr) +{ + free(ptr); +} + +/* +Declaration of the custom functions used if LODEPNG_COMPILE_ZLIB isn't defined +or LODEPNG_CUSTOM_ZLIB_DECODER or LODEPNG_CUSTOM_ZLIB_ENCODER are enabled. + +In that case, you need to define these yourself (which you can do in one of your +own source files) so that LodePNG can link to it. + +By default, this is not needed. If LODEPNG_COMPILE_ZLIB isn't defined, then only +the two zlib related ones are needed. + +If needed, the functions must act as follows: +*out must be NULL and *outsize must be 0 initially, and after the function is done, +*out must point to the decompressed data, *outsize must be the size of it, and must +be the size of the useful data in bytes, not the alloc size. +*/ +unsigned lodepng_custom_zlib_decompress(unsigned char** out, size_t* outsize, + const unsigned char* in, size_t insize, + const LodePNGDecompressSettings* settings); +unsigned lodepng_custom_zlib_compress(unsigned char** out, size_t* outsize, + const unsigned char* in, size_t insize, + const LodePNGCompressSettings* settings); +unsigned lodepng_custom_inflate(unsigned char** out, size_t* outsize, + const unsigned char* in, size_t insize, + const LodePNGDecompressSettings* settings); +unsigned lodepng_custom_deflate(unsigned char** out, size_t* outsize, + const unsigned char* in, size_t insize, + const LodePNGCompressSettings* settings); + +/* ////////////////////////////////////////////////////////////////////////// */ +/* ////////////////////////////////////////////////////////////////////////// */ +/* // Tools for C, and common code for PNG and Zlib. // */ +/* ////////////////////////////////////////////////////////////////////////// */ +/* ////////////////////////////////////////////////////////////////////////// */ + +/* +Often in case of an error a value is assigned to a variable and then it breaks +out of a loop (to go to the cleanup phase of a function). This macro does that. +It makes the error handling code shorter and more readable. + +Example: if(!uivector_resizev(&frequencies_ll, 286, 0)) ERROR_BREAK(83); +*/ +#define CERROR_BREAK(errorvar, code)\ +{\ + errorvar = code;\ + break;\ +} + +/*version of CERROR_BREAK that assumes the common case where the error variable is named "error"*/ +#define ERROR_BREAK(code) CERROR_BREAK(error, code) + +/*Set error var to the error code, and return it.*/ +#define CERROR_RETURN_ERROR(errorvar, code)\ +{\ + errorvar = code;\ + return code;\ +} + +/*Try the code, if it returns error, also return the error.*/ +#define CERROR_TRY_RETURN(call)\ +{\ + unsigned error = call;\ + if(error) return error;\ +} + +/* +About uivector, ucvector and string: +-All of them wrap dynamic arrays or text strings in a similar way. +-LodePNG was originally written in C++. The vectors replace the std::vectors that were used in the C++ version. +-The string tools are made to avoid problems with compilers that declare things like strncat as deprecated. +-They're not used in the interface, only internally in this file as static functions. +-As with many other structs in this file, the init and cleanup functions serve as ctor and dtor. +*/ + +#ifdef LODEPNG_COMPILE_ZLIB +/*dynamic vector of unsigned ints*/ +typedef struct uivector +{ + unsigned* data; + size_t size; /*size in number of unsigned longs*/ + size_t allocsize; /*allocated size in bytes*/ +} uivector; + +static void uivector_cleanup(void* p) +{ + ((uivector*)p)->size = ((uivector*)p)->allocsize = 0; + myfree(((uivector*)p)->data); + ((uivector*)p)->data = NULL; +} + +/*returns 1 if success, 0 if failure ==> nothing done*/ +static unsigned uivector_resize(uivector* p, size_t size) +{ + if(size * sizeof(unsigned) > p->allocsize) + { + size_t newsize = size * sizeof(unsigned) * 2; + void* data = myrealloc(p->data, newsize); + if(data) + { + p->allocsize = newsize; + p->data = (unsigned*)data; + p->size = size; + } + else return 0; + } + else p->size = size; + return 1; +} + +/*resize and give all new elements the value*/ +static unsigned uivector_resizev(uivector* p, size_t size, unsigned value) +{ + size_t oldsize = p->size, i; + if(!uivector_resize(p, size)) return 0; + for(i = oldsize; i < size; i++) p->data[i] = value; + return 1; +} + +static void uivector_init(uivector* p) +{ + p->data = NULL; + p->size = p->allocsize = 0; +} + +#ifdef LODEPNG_COMPILE_ENCODER +/*returns 1 if success, 0 if failure ==> nothing done*/ +static unsigned uivector_push_back(uivector* p, unsigned c) +{ + if(!uivector_resize(p, p->size + 1)) return 0; + p->data[p->size - 1] = c; + return 1; +} + +/*copy q to p, returns 1 if success, 0 if failure ==> nothing done*/ +static unsigned uivector_copy(uivector* p, const uivector* q) +{ + size_t i; + if(!uivector_resize(p, q->size)) return 0; + for(i = 0; i < q->size; i++) p->data[i] = q->data[i]; + return 1; +} + +static void uivector_swap(uivector* p, uivector* q) +{ + size_t tmp; + unsigned* tmpp; + tmp = p->size; p->size = q->size; q->size = tmp; + tmp = p->allocsize; p->allocsize = q->allocsize; q->allocsize = tmp; + tmpp = p->data; p->data = q->data; q->data = tmpp; +} +#endif /*LODEPNG_COMPILE_ENCODER*/ +#endif /*LODEPNG_COMPILE_ZLIB*/ + +/* /////////////////////////////////////////////////////////////////////////// */ + +/*dynamic vector of unsigned chars*/ +typedef struct ucvector +{ + unsigned char* data; + size_t size; /*used size*/ + size_t allocsize; /*allocated size*/ +} ucvector; + +static void ucvector_cleanup(void* p) +{ + ((ucvector*)p)->size = ((ucvector*)p)->allocsize = 0; + myfree(((ucvector*)p)->data); + ((ucvector*)p)->data = NULL; +} + +/*returns 1 if success, 0 if failure ==> nothing done*/ +static unsigned ucvector_resize(ucvector* p, size_t size) +{ + if(size * sizeof(unsigned char) > p->allocsize) + { + size_t newsize = size * sizeof(unsigned char) * 2; + void* data = myrealloc(p->data, newsize); + if(data) + { + p->allocsize = newsize; + p->data = (unsigned char*)data; + p->size = size; + } + else return 0; /*error: not enough memory*/ + } + else p->size = size; + return 1; +} + +#ifdef LODEPNG_COMPILE_DECODER +#ifdef LODEPNG_COMPILE_PNG +/*resize and give all new elements the value*/ +static unsigned ucvector_resizev(ucvector* p, size_t size, unsigned char value) +{ + size_t oldsize = p->size, i; + if(!ucvector_resize(p, size)) return 0; + for(i = oldsize; i < size; i++) p->data[i] = value; + return 1; +} +#endif /*LODEPNG_COMPILE_PNG*/ +#endif /*LODEPNG_COMPILE_DECODER*/ + +static void ucvector_init(ucvector* p) +{ + p->data = NULL; + p->size = p->allocsize = 0; +} + +#ifdef LODEPNG_COMPILE_ZLIB +/*you can both convert from vector to buffer&size and vica versa. If you use +init_buffer to take over a buffer and size, it is not needed to use cleanup*/ +static void ucvector_init_buffer(ucvector* p, unsigned char* buffer, size_t size) +{ + p->data = buffer; + p->allocsize = p->size = size; +} +#endif /*LODEPNG_COMPILE_ZLIB*/ + +#ifdef LODEPNG_COMPILE_ENCODER +/*returns 1 if success, 0 if failure ==> nothing done*/ +static unsigned ucvector_push_back(ucvector* p, unsigned char c) +{ + if(!ucvector_resize(p, p->size + 1)) return 0; + p->data[p->size - 1] = c; + return 1; +} +#endif /*LODEPNG_COMPILE_ENCODER*/ + + +/* ////////////////////////////////////////////////////////////////////////// */ + +#ifdef LODEPNG_COMPILE_PNG +#ifdef LODEPNG_COMPILE_ANCILLARY_CHUNKS +/*returns 1 if success, 0 if failure ==> nothing done*/ +static unsigned string_resize(char** out, size_t size) +{ + char* data = (char*)myrealloc(*out, size + 1); + if(data) + { + data[size] = 0; /*null termination char*/ + *out = data; + } + return data != 0; +} + +/*init a {char*, size_t} pair for use as string*/ +static void string_init(char** out) +{ + *out = NULL; + string_resize(out, 0); +} + +/*free the above pair again*/ +static void string_cleanup(char** out) +{ + myfree(*out); + *out = NULL; +} + +static void string_set(char** out, const char* in) +{ + size_t insize = strlen(in), i = 0; + if(string_resize(out, insize)) + { + for(i = 0; i < insize; i++) + { + (*out)[i] = in[i]; + } + } +} +#endif /*LODEPNG_COMPILE_ANCILLARY_CHUNKS*/ +#endif /*LODEPNG_COMPILE_PNG*/ + +/* ////////////////////////////////////////////////////////////////////////// */ + +unsigned lodepng_read32bitInt(const unsigned char* buffer) +{ + return (buffer[0] << 24) | (buffer[1] << 16) | (buffer[2] << 8) | buffer[3]; +} + +/*buffer must have at least 4 allocated bytes available*/ +static void lodepng_set32bitInt(unsigned char* buffer, unsigned value) +{ + buffer[0] = (unsigned char)((value >> 24) & 0xff); + buffer[1] = (unsigned char)((value >> 16) & 0xff); + buffer[2] = (unsigned char)((value >> 8) & 0xff); + buffer[3] = (unsigned char)((value ) & 0xff); +} + +#ifdef LODEPNG_COMPILE_ENCODER +static void lodepng_add32bitInt(ucvector* buffer, unsigned value) +{ + ucvector_resize(buffer, buffer->size + 4); /*todo: give error if resize failed*/ + lodepng_set32bitInt(&buffer->data[buffer->size - 4], value); +} +#endif /*LODEPNG_COMPILE_ENCODER*/ + +/* ////////////////////////////////////////////////////////////////////////// */ +/* / File IO / */ +/* ////////////////////////////////////////////////////////////////////////// */ + +#ifdef LODEPNG_COMPILE_DISK + +unsigned lodepng_load_file(unsigned char** out, size_t* outsize, const char* filename) +{ + FILE* file; + long size; + + /*provide some proper output values if error will happen*/ + *out = 0; + *outsize = 0; + + file = fopen(filename, "rb"); + if(!file) return 78; + + /*get filesize:*/ + fseek(file , 0 , SEEK_END); + size = ftell(file); + rewind(file); + + /*read contents of the file into the vector*/ + *outsize = 0; + *out = (unsigned char*)mymalloc((size_t)size); + if(size && (*out)) (*outsize) = fread(*out, 1, (size_t)size, file); + + fclose(file); + if(!(*out) && size) return 83; /*the above malloc failed*/ + return 0; +} + +/*write given buffer to the file, overwriting the file, it doesn't append to it.*/ +unsigned lodepng_save_file(const unsigned char* buffer, size_t buffersize, const char* filename) +{ + FILE* file; + file = fopen(filename, "wb" ); + if(!file) return 79; + fwrite((char*)buffer , 1 , buffersize, file); + fclose(file); + return 0; +} + +#endif /*LODEPNG_COMPILE_DISK*/ + +/* ////////////////////////////////////////////////////////////////////////// */ +/* ////////////////////////////////////////////////////////////////////////// */ +/* // End of common code and tools. Begin of Zlib related code. // */ +/* ////////////////////////////////////////////////////////////////////////// */ +/* ////////////////////////////////////////////////////////////////////////// */ + +#ifdef LODEPNG_COMPILE_ZLIB +#ifdef LODEPNG_COMPILE_ENCODER +/*TODO: this ignores potential out of memory errors*/ +static void addBitToStream(size_t* bitpointer, ucvector* bitstream, unsigned char bit) +{ + /*add a new byte at the end*/ + if((*bitpointer) % 8 == 0) ucvector_push_back(bitstream, (unsigned char)0); + /*earlier bit of huffman code is in a lesser significant bit of an earlier byte*/ + (bitstream->data[bitstream->size - 1]) |= (bit << ((*bitpointer) & 0x7)); + (*bitpointer)++; +} + +static void addBitsToStream(size_t* bitpointer, ucvector* bitstream, unsigned value, size_t nbits) +{ + size_t i; + for(i = 0; i < nbits; i++) addBitToStream(bitpointer, bitstream, (unsigned char)((value >> i) & 1)); +} + +static void addBitsToStreamReversed(size_t* bitpointer, ucvector* bitstream, unsigned value, size_t nbits) +{ + size_t i; + for(i = 0; i < nbits; i++) addBitToStream(bitpointer, bitstream, (unsigned char)((value >> (nbits - 1 - i)) & 1)); +} +#endif /*LODEPNG_COMPILE_ENCODER*/ + +#ifdef LODEPNG_COMPILE_DECODER + +#define READBIT(bitpointer, bitstream) ((bitstream[bitpointer >> 3] >> (bitpointer & 0x7)) & (unsigned char)1) + +static unsigned char readBitFromStream(size_t* bitpointer, const unsigned char* bitstream) +{ + unsigned char result = (unsigned char)(READBIT(*bitpointer, bitstream)); + (*bitpointer)++; + return result; +} + +static unsigned readBitsFromStream(size_t* bitpointer, const unsigned char* bitstream, size_t nbits) +{ + unsigned result = 0, i; + for(i = 0; i < nbits; i++) + { + result += ((unsigned)READBIT(*bitpointer, bitstream)) << i; + (*bitpointer)++; + } + return result; +} +#endif /*LODEPNG_COMPILE_DECODER*/ + +/* ////////////////////////////////////////////////////////////////////////// */ +/* / Deflate - Huffman / */ +/* ////////////////////////////////////////////////////////////////////////// */ + +#define FIRST_LENGTH_CODE_INDEX 257 +#define LAST_LENGTH_CODE_INDEX 285 +/*256 literals, the end code, some length codes, and 2 unused codes*/ +#define NUM_DEFLATE_CODE_SYMBOLS 288 +/*the distance codes have their own symbols, 30 used, 2 unused*/ +#define NUM_DISTANCE_SYMBOLS 32 +/*the code length codes. 0-15: code lengths, 16: copy previous 3-6 times, 17: 3-10 zeros, 18: 11-138 zeros*/ +#define NUM_CODE_LENGTH_CODES 19 + +/*the base lengths represented by codes 257-285*/ +static const unsigned LENGTHBASE[29] + = {3, 4, 5, 6, 7, 8, 9, 10, 11, 13, 15, 17, 19, 23, 27, 31, 35, 43, 51, 59, + 67, 83, 99, 115, 131, 163, 195, 227, 258}; + +/*the extra bits used by codes 257-285 (added to base length)*/ +static const unsigned LENGTHEXTRA[29] + = {0, 0, 0, 0, 0, 0, 0, 0, 1, 1, 1, 1, 2, 2, 2, 2, 3, 3, 3, 3, + 4, 4, 4, 4, 5, 5, 5, 5, 0}; + +/*the base backwards distances (the bits of distance codes appear after length codes and use their own huffman tree)*/ +static const unsigned DISTANCEBASE[30] + = {1, 2, 3, 4, 5, 7, 9, 13, 17, 25, 33, 49, 65, 97, 129, 193, 257, 385, 513, + 769, 1025, 1537, 2049, 3073, 4097, 6145, 8193, 12289, 16385, 24577}; + +/*the extra bits of backwards distances (added to base)*/ +static const unsigned DISTANCEEXTRA[30] + = {0, 0, 0, 0, 1, 1, 2, 2, 3, 3, 4, 4, 5, 5, 6, 6, 7, 7, 8, + 8, 9, 9, 10, 10, 11, 11, 12, 12, 13, 13}; + +/*the order in which "code length alphabet code lengths" are stored, out of this +the huffman tree of the dynamic huffman tree lengths is generated*/ +static const unsigned CLCL_ORDER[NUM_CODE_LENGTH_CODES] + = {16, 17, 18, 0, 8, 7, 9, 6, 10, 5, 11, 4, 12, 3, 13, 2, 14, 1, 15}; + +/* ////////////////////////////////////////////////////////////////////////// */ + +/* +Huffman tree struct, containing multiple representations of the tree +*/ +typedef struct HuffmanTree +{ + unsigned* tree2d; + unsigned* tree1d; + unsigned* lengths; /*the lengths of the codes of the 1d-tree*/ + unsigned maxbitlen; /*maximum number of bits a single code can get*/ + unsigned numcodes; /*number of symbols in the alphabet = number of codes*/ +} HuffmanTree; + +/*function used for debug purposes to draw the tree in ascii art with C++*/ +/*#include +static void HuffmanTree_draw(HuffmanTree* tree) +{ + std::cout << "tree. length: " << tree->numcodes << " maxbitlen: " << tree->maxbitlen << std::endl; + for(size_t i = 0; i < tree->tree1d.size; i++) + { + if(tree->lengths.data[i]) + std::cout << i << " " << tree->tree1d.data[i] << " " << tree->lengths.data[i] << std::endl; + } + std::cout << std::endl; +}*/ + +static void HuffmanTree_init(HuffmanTree* tree) +{ + tree->tree2d = 0; + tree->tree1d = 0; + tree->lengths = 0; +} + +static void HuffmanTree_cleanup(HuffmanTree* tree) +{ + myfree(tree->tree2d); + myfree(tree->tree1d); + myfree(tree->lengths); +} + +/*the tree representation used by the decoder. return value is error*/ +static unsigned HuffmanTree_make2DTree(HuffmanTree* tree) +{ + unsigned nodefilled = 0; /*up to which node it is filled*/ + unsigned treepos = 0; /*position in the tree (1 of the numcodes columns)*/ + unsigned n, i; + + tree->tree2d = (unsigned*)mymalloc(tree->numcodes * 2 * sizeof(unsigned)); + if(!tree->tree2d) return 83; /*alloc fail*/ + + /* + convert tree1d[] to tree2d[][]. In the 2D array, a value of 32767 means + uninited, a value >= numcodes is an address to another bit, a value < numcodes + is a code. The 2 rows are the 2 possible bit values (0 or 1), there are as + many columns as codes - 1. + A good huffmann tree has N * 2 - 1 nodes, of which N - 1 are internal nodes. + Here, the internal nodes are stored (what their 0 and 1 option point to). + There is only memory for such good tree currently, if there are more nodes + (due to too long length codes), error 55 will happen + */ + for(n = 0; n < tree->numcodes * 2; n++) + { + tree->tree2d[n] = 32767; /*32767 here means the tree2d isn't filled there yet*/ + } + + for(n = 0; n < tree->numcodes; n++) /*the codes*/ + { + for(i = 0; i < tree->lengths[n]; i++) /*the bits for this code*/ + { + unsigned char bit = (unsigned char)((tree->tree1d[n] >> (tree->lengths[n] - i - 1)) & 1); + if(treepos > tree->numcodes - 2) return 55; /*oversubscribed, see comment in lodepng_error_text*/ + if(tree->tree2d[2 * treepos + bit] == 32767) /*not yet filled in*/ + { + if(i + 1 == tree->lengths[n]) /*last bit*/ + { + tree->tree2d[2 * treepos + bit] = n; /*put the current code in it*/ + treepos = 0; + } + else + { + /*put address of the next step in here, first that address has to be found of course + (it's just nodefilled + 1)...*/ + nodefilled++; + /*addresses encoded with numcodes added to it*/ + tree->tree2d[2 * treepos + bit] = nodefilled + tree->numcodes; + treepos = nodefilled; + } + } + else treepos = tree->tree2d[2 * treepos + bit] - tree->numcodes; + } + } + + for(n = 0; n < tree->numcodes * 2; n++) + { + if(tree->tree2d[n] == 32767) tree->tree2d[n] = 0; /*remove possible remaining 32767's*/ + } + + return 0; +} + +/* +Second step for the ...makeFromLengths and ...makeFromFrequencies functions. +numcodes, lengths and maxbitlen must already be filled in correctly. return +value is error. +*/ +static unsigned HuffmanTree_makeFromLengths2(HuffmanTree* tree) +{ + uivector blcount; + uivector nextcode; + unsigned bits, n, error = 0; + + uivector_init(&blcount); + uivector_init(&nextcode); + + tree->tree1d = (unsigned*)mymalloc(tree->numcodes * sizeof(unsigned)); + if(!tree->tree1d) error = 83; /*alloc fail*/ + + if(!uivector_resizev(&blcount, tree->maxbitlen + 1, 0) + || !uivector_resizev(&nextcode, tree->maxbitlen + 1, 0)) + error = 83; /*alloc fail*/ + + if(!error) + { + /*step 1: count number of instances of each code length*/ + for(bits = 0; bits < tree->numcodes; bits++) blcount.data[tree->lengths[bits]]++; + /*step 2: generate the nextcode values*/ + for(bits = 1; bits <= tree->maxbitlen; bits++) + { + nextcode.data[bits] = (nextcode.data[bits - 1] + blcount.data[bits - 1]) << 1; + } + /*step 3: generate all the codes*/ + for(n = 0; n < tree->numcodes; n++) + { + if(tree->lengths[n] != 0) tree->tree1d[n] = nextcode.data[tree->lengths[n]]++; + } + } + + uivector_cleanup(&blcount); + uivector_cleanup(&nextcode); + + if(!error) return HuffmanTree_make2DTree(tree); + else return error; +} + +/* +given the code lengths (as stored in the PNG file), generate the tree as defined +by Deflate. maxbitlen is the maximum bits that a code in the tree can have. +return value is error. +*/ +static unsigned HuffmanTree_makeFromLengths(HuffmanTree* tree, const unsigned* bitlen, + size_t numcodes, unsigned maxbitlen) +{ + unsigned i; + tree->lengths = (unsigned*)mymalloc(numcodes * sizeof(unsigned)); + if(!tree->lengths) return 83; /*alloc fail*/ + for(i = 0; i < numcodes; i++) tree->lengths[i] = bitlen[i]; + tree->numcodes = (unsigned)numcodes; /*number of symbols*/ + tree->maxbitlen = maxbitlen; + return HuffmanTree_makeFromLengths2(tree); +} + +#ifdef LODEPNG_COMPILE_ENCODER + +/* +A coin, this is the terminology used for the package-merge algorithm and the +coin collector's problem. This is used to generate the huffman tree. +A coin can be multiple coins (when they're merged) +*/ +typedef struct Coin +{ + uivector symbols; + float weight; /*the sum of all weights in this coin*/ +} Coin; + +static void coin_init(Coin* c) +{ + uivector_init(&c->symbols); +} + +/*argument c is void* so that this dtor can be given as function pointer to the vector resize function*/ +static void coin_cleanup(void* c) +{ + uivector_cleanup(&((Coin*)c)->symbols); +} + +static void coin_copy(Coin* c1, const Coin* c2) +{ + c1->weight = c2->weight; + uivector_copy(&c1->symbols, &c2->symbols); +} + +static void add_coins(Coin* c1, const Coin* c2) +{ + size_t i; + for(i = 0; i < c2->symbols.size; i++) uivector_push_back(&c1->symbols, c2->symbols.data[i]); + c1->weight += c2->weight; +} + +static void init_coins(Coin* coins, size_t num) +{ + size_t i; + for(i = 0; i < num; i++) coin_init(&coins[i]); +} + +static void cleanup_coins(Coin* coins, size_t num) +{ + size_t i; + for(i = 0; i < num; i++) coin_cleanup(&coins[i]); +} + +/* +This uses a simple combsort to sort the data. This function is not critical for +overall encoding speed and the data amount isn't that large. +*/ +static void sort_coins(Coin* data, size_t amount) +{ + size_t gap = amount; + unsigned char swapped = 0; + while((gap > 1) || swapped) + { + size_t i; + gap = (gap * 10) / 13; /*shrink factor 1.3*/ + if(gap == 9 || gap == 10) gap = 11; /*combsort11*/ + if(gap < 1) gap = 1; + swapped = 0; + for(i = 0; i < amount - gap; i++) + { + size_t j = i + gap; + if(data[j].weight < data[i].weight) + { + float temp = data[j].weight; data[j].weight = data[i].weight; data[i].weight = temp; + uivector_swap(&data[i].symbols, &data[j].symbols); + swapped = 1; + } + } + } +} + +static unsigned append_symbol_coins(Coin* coins, const unsigned* frequencies, unsigned numcodes, size_t sum) +{ + unsigned i; + unsigned j = 0; /*index of present symbols*/ + for(i = 0; i < numcodes; i++) + { + if(frequencies[i] != 0) /*only include symbols that are present*/ + { + coins[j].weight = frequencies[i] / (float)sum; + uivector_push_back(&coins[j].symbols, i); + j++; + } + } + return 0; +} + +unsigned lodepng_huffman_code_lengths(unsigned* lengths, const unsigned* frequencies, + size_t numcodes, unsigned maxbitlen) +{ + unsigned i, j; + size_t sum = 0, numpresent = 0; + unsigned error = 0; + Coin* coins; /*the coins of the currently calculated row*/ + Coin* prev_row; /*the previous row of coins*/ + unsigned numcoins; + unsigned coinmem; + + if(numcodes == 0) return 80; /*error: a tree of 0 symbols is not supposed to be made*/ + + for(i = 0; i < numcodes; i++) + { + if(frequencies[i] > 0) + { + numpresent++; + sum += frequencies[i]; + } + } + + for(i = 0; i < numcodes; i++) lengths[i] = 0; + + /*there are no symbols at all, in that case add one symbol of value 0 to the tree (see RFC 1951 section 3.2.7) */ + if(numpresent == 0) + { + lengths[0] = 1; + } + /*the package merge algorithm gives wrong results if there's only one symbol + (theoretically 0 bits would then suffice, but we need a proper symbol for zlib)*/ + else if(numpresent == 1) + { + for(i = 0; i < numcodes; i++) if(frequencies[i]) lengths[i] = 1; + } + else + { + /*Package-Merge algorithm represented by coin collector's problem + For every symbol, maxbitlen coins will be created*/ + + coinmem = numpresent * 2; /*max amount of coins needed with the current algo*/ + coins = (Coin*)mymalloc(sizeof(Coin) * coinmem); + prev_row = (Coin*)mymalloc(sizeof(Coin) * coinmem); + if(!coins || !prev_row) return 83; /*alloc fail*/ + init_coins(coins, coinmem); + init_coins(prev_row, coinmem); + + /*first row, lowest denominator*/ + error = append_symbol_coins(coins, frequencies, numcodes, sum); + numcoins = numpresent; + sort_coins(coins, numcoins); + if(!error) + { + unsigned numprev = 0; + for(j = 1; j <= maxbitlen && !error; j++) /*each of the remaining rows*/ + { + unsigned tempnum; + Coin* tempcoins; + /*swap prev_row and coins, and their amounts*/ + tempcoins = prev_row; prev_row = coins; coins = tempcoins; + tempnum = numprev; numprev = numcoins; numcoins = tempnum; + + cleanup_coins(coins, numcoins); + init_coins(coins, numcoins); + + numcoins = 0; + + /*fill in the merged coins of the previous row*/ + for(i = 0; i + 1 < numprev; i += 2) + { + /*merge prev_row[i] and prev_row[i + 1] into new coin*/ + Coin* coin = &coins[numcoins++]; + coin_copy(coin, &prev_row[i]); + add_coins(coin, &prev_row[i + 1]); + } + /*fill in all the original symbols again*/ + if(j < maxbitlen) + { + error = append_symbol_coins(coins + numcoins, frequencies, numcodes, sum); + numcoins += numpresent; + } + sort_coins(coins, numcoins); + } + } + + if(!error) + { + /*calculate the lenghts of each symbol, as the amount of times a coin of each symbol is used*/ + for(i = 0; i < numpresent - 1; i++) + { + Coin* coin = &coins[i]; + for(j = 0; j < coin->symbols.size; j++) lengths[coin->symbols.data[j]]++; + } + } + + cleanup_coins(coins, coinmem); + myfree(coins); + cleanup_coins(prev_row, coinmem); + myfree(prev_row); + } + + return error; +} + +/*Create the Huffman tree given the symbol frequencies*/ +static unsigned HuffmanTree_makeFromFrequencies(HuffmanTree* tree, const unsigned* frequencies, + size_t numcodes, unsigned maxbitlen) +{ + unsigned error = 0; + tree->maxbitlen = maxbitlen; + tree->numcodes = (unsigned)numcodes; /*number of symbols*/ + tree->lengths = (unsigned*)myrealloc(tree->lengths, numcodes * sizeof(unsigned)); + if(!tree->lengths) return 83; /*alloc fail*/ + /*initialize all lengths to 0*/ + memset(tree->lengths, 0, numcodes * sizeof(unsigned)); + + error = lodepng_huffman_code_lengths(tree->lengths, frequencies, numcodes, maxbitlen); + if(!error) error = HuffmanTree_makeFromLengths2(tree); + return error; +} + +static unsigned HuffmanTree_getCode(const HuffmanTree* tree, unsigned index) +{ + return tree->tree1d[index]; +} + +static unsigned HuffmanTree_getLength(const HuffmanTree* tree, unsigned index) +{ + return tree->lengths[index]; +} +#endif /*LODEPNG_COMPILE_ENCODER*/ + +/*get the literal and length code tree of a deflated block with fixed tree, as per the deflate specification*/ +static unsigned generateFixedLitLenTree(HuffmanTree* tree) +{ + unsigned i, error = 0; + unsigned* bitlen = (unsigned*)mymalloc(NUM_DEFLATE_CODE_SYMBOLS * sizeof(unsigned)); + if(!bitlen) return 83; /*alloc fail*/ + + /*288 possible codes: 0-255=literals, 256=endcode, 257-285=lengthcodes, 286-287=unused*/ + for(i = 0; i <= 143; i++) bitlen[i] = 8; + for(i = 144; i <= 255; i++) bitlen[i] = 9; + for(i = 256; i <= 279; i++) bitlen[i] = 7; + for(i = 280; i <= 287; i++) bitlen[i] = 8; + + error = HuffmanTree_makeFromLengths(tree, bitlen, NUM_DEFLATE_CODE_SYMBOLS, 15); + + myfree(bitlen); + return error; +} + +/*get the distance code tree of a deflated block with fixed tree, as specified in the deflate specification*/ +static unsigned generateFixedDistanceTree(HuffmanTree* tree) +{ + unsigned i, error = 0; + unsigned* bitlen = (unsigned*)mymalloc(NUM_DISTANCE_SYMBOLS * sizeof(unsigned)); + if(!bitlen) return 83; /*alloc fail*/ + + /*there are 32 distance codes, but 30-31 are unused*/ + for(i = 0; i < NUM_DISTANCE_SYMBOLS; i++) bitlen[i] = 5; + error = HuffmanTree_makeFromLengths(tree, bitlen, NUM_DISTANCE_SYMBOLS, 15); + + myfree(bitlen); + return error; +} + +#ifdef LODEPNG_COMPILE_DECODER + +/* +returns the code, or (unsigned)(-1) if error happened +inbitlength is the length of the complete buffer, in bits (so its byte length times 8) +*/ +static unsigned huffmanDecodeSymbol(const unsigned char* in, size_t* bp, + const HuffmanTree* codetree, size_t inbitlength) +{ + unsigned treepos = 0, ct; + for(;;) + { + if(*bp >= inbitlength) return (unsigned)(-1); /*error: end of input memory reached without endcode*/ + /* + decode the symbol from the tree. The "readBitFromStream" code is inlined in + the expression below because this is the biggest bottleneck while decoding + */ + ct = codetree->tree2d[(treepos << 1) + READBIT(*bp, in)]; + (*bp)++; + if(ct < codetree->numcodes) return ct; /*the symbol is decoded, return it*/ + else treepos = ct - codetree->numcodes; /*symbol not yet decoded, instead move tree position*/ + + if(treepos >= codetree->numcodes) return (unsigned)(-1); /*error: it appeared outside the codetree*/ + } +} +#endif /*LODEPNG_COMPILE_DECODER*/ + +#ifdef LODEPNG_COMPILE_DECODER + +/* ////////////////////////////////////////////////////////////////////////// */ +/* / Inflator (Decompressor) / */ +/* ////////////////////////////////////////////////////////////////////////// */ + +/*get the tree of a deflated block with fixed tree, as specified in the deflate specification*/ +static void getTreeInflateFixed(HuffmanTree* tree_ll, HuffmanTree* tree_d) +{ + /*TODO: check for out of memory errors*/ + generateFixedLitLenTree(tree_ll); + generateFixedDistanceTree(tree_d); +} + +/*get the tree of a deflated block with dynamic tree, the tree itself is also Huffman compressed with a known tree*/ +static unsigned getTreeInflateDynamic(HuffmanTree* tree_ll, HuffmanTree* tree_d, + const unsigned char* in, size_t* bp, size_t inlength) +{ + /*make sure that length values that aren't filled in will be 0, or a wrong tree will be generated*/ + unsigned error = 0; + unsigned n, HLIT, HDIST, HCLEN, i; + size_t inbitlength = inlength * 8; + + /*see comments in deflateDynamic for explanation of the context and these variables, it is analogous*/ + unsigned* bitlen_ll = 0; /*lit,len code lengths*/ + unsigned* bitlen_d = 0; /*dist code lengths*/ + /*code length code lengths ("clcl"), the bit lengths of the huffman tree used to compress bitlen_ll and bitlen_d*/ + unsigned* bitlen_cl = 0; + HuffmanTree tree_cl; /*the code tree for code length codes (the huffman tree for compressed huffman trees)*/ + + if((*bp) >> 3 >= inlength - 2) return 49; /*error: the bit pointer is or will go past the memory*/ + + /*number of literal/length codes + 257. Unlike the spec, the value 257 is added to it here already*/ + HLIT = readBitsFromStream(bp, in, 5) + 257; + /*number of distance codes. Unlike the spec, the value 1 is added to it here already*/ + HDIST = readBitsFromStream(bp, in, 5) + 1; + /*number of code length codes. Unlike the spec, the value 4 is added to it here already*/ + HCLEN = readBitsFromStream(bp, in, 4) + 4; + + HuffmanTree_init(&tree_cl); + + while(!error) + { + /*read the code length codes out of 3 * (amount of code length codes) bits*/ + + bitlen_cl = (unsigned*)mymalloc(NUM_CODE_LENGTH_CODES * sizeof(unsigned)); + if(!bitlen_cl) ERROR_BREAK(83 /*alloc fail*/); + + for(i = 0; i < NUM_CODE_LENGTH_CODES; i++) + { + if(i < HCLEN) bitlen_cl[CLCL_ORDER[i]] = readBitsFromStream(bp, in, 3); + else bitlen_cl[CLCL_ORDER[i]] = 0; /*if not, it must stay 0*/ + } + + error = HuffmanTree_makeFromLengths(&tree_cl, bitlen_cl, NUM_CODE_LENGTH_CODES, 7); + if(error) break; + + /*now we can use this tree to read the lengths for the tree that this function will return*/ + bitlen_ll = (unsigned*)mymalloc(NUM_DEFLATE_CODE_SYMBOLS * sizeof(unsigned)); + bitlen_d = (unsigned*)mymalloc(NUM_DISTANCE_SYMBOLS * sizeof(unsigned)); + if(!bitlen_ll || !bitlen_d) ERROR_BREAK(83 /*alloc fail*/); + for(i = 0; i < NUM_DEFLATE_CODE_SYMBOLS; i++) bitlen_ll[i] = 0; + for(i = 0; i < NUM_DISTANCE_SYMBOLS; i++) bitlen_d[i] = 0; + + /*i is the current symbol we're reading in the part that contains the code lengths of lit/len and dist codes*/ + i = 0; + while(i < HLIT + HDIST) + { + unsigned code = huffmanDecodeSymbol(in, bp, &tree_cl, inbitlength); + if(code <= 15) /*a length code*/ + { + if(i < HLIT) bitlen_ll[i] = code; + else bitlen_d[i - HLIT] = code; + i++; + } + else if(code == 16) /*repeat previous*/ + { + unsigned replength = 3; /*read in the 2 bits that indicate repeat length (3-6)*/ + unsigned value; /*set value to the previous code*/ + + if(*bp >= inbitlength) ERROR_BREAK(50); /*error, bit pointer jumps past memory*/ + if (i == 0) ERROR_BREAK(54); /*can't repeat previous if i is 0*/ + + replength += readBitsFromStream(bp, in, 2); + + if(i < HLIT + 1) value = bitlen_ll[i - 1]; + else value = bitlen_d[i - HLIT - 1]; + /*repeat this value in the next lengths*/ + for(n = 0; n < replength; n++) + { + if(i >= HLIT + HDIST) ERROR_BREAK(13); /*error: i is larger than the amount of codes*/ + if(i < HLIT) bitlen_ll[i] = value; + else bitlen_d[i - HLIT] = value; + i++; + } + } + else if(code == 17) /*repeat "0" 3-10 times*/ + { + unsigned replength = 3; /*read in the bits that indicate repeat length*/ + if(*bp >= inbitlength) ERROR_BREAK(50); /*error, bit pointer jumps past memory*/ + + replength += readBitsFromStream(bp, in, 3); + + /*repeat this value in the next lengths*/ + for(n = 0; n < replength; n++) + { + if(i >= HLIT + HDIST) ERROR_BREAK(14); /*error: i is larger than the amount of codes*/ + + if(i < HLIT) bitlen_ll[i] = 0; + else bitlen_d[i - HLIT] = 0; + i++; + } + } + else if(code == 18) /*repeat "0" 11-138 times*/ + { + unsigned replength = 11; /*read in the bits that indicate repeat length*/ + if(*bp >= inbitlength) ERROR_BREAK(50); /*error, bit pointer jumps past memory*/ + + replength += readBitsFromStream(bp, in, 7); + + /*repeat this value in the next lengths*/ + for(n = 0; n < replength; n++) + { + if(i >= HLIT + HDIST) ERROR_BREAK(15); /*error: i is larger than the amount of codes*/ + + if(i < HLIT) bitlen_ll[i] = 0; + else bitlen_d[i - HLIT] = 0; + i++; + } + } + else /*if(code == (unsigned)(-1))*/ /*huffmanDecodeSymbol returns (unsigned)(-1) in case of error*/ + { + if(code == (unsigned)(-1)) + { + /*return error code 10 or 11 depending on the situation that happened in huffmanDecodeSymbol + (10=no endcode, 11=wrong jump outside of tree)*/ + error = (*bp) > inbitlength ? 10 : 11; + } + else error = 16; /*unexisting code, this can never happen*/ + break; + } + } + if(error) break; + + if(bitlen_ll[256] == 0) ERROR_BREAK(64); /*the length of the end code 256 must be larger than 0*/ + + /*now we've finally got HLIT and HDIST, so generate the code trees, and the function is done*/ + error = HuffmanTree_makeFromLengths(tree_ll, bitlen_ll, NUM_DEFLATE_CODE_SYMBOLS, 15); + if(error) break; + error = HuffmanTree_makeFromLengths(tree_d, bitlen_d, NUM_DISTANCE_SYMBOLS, 15); + + break; /*end of error-while*/ + } + + myfree(bitlen_cl); + myfree(bitlen_ll); + myfree(bitlen_d); + HuffmanTree_cleanup(&tree_cl); + + return error; +} + +/*inflate a block with dynamic of fixed Huffman tree*/ +static unsigned inflateHuffmanBlock(ucvector* out, const unsigned char* in, size_t* bp, + size_t* pos, size_t inlength, unsigned btype) +{ + unsigned error = 0; + HuffmanTree tree_ll; /*the huffman tree for literal and length codes*/ + HuffmanTree tree_d; /*the huffman tree for distance codes*/ + size_t inbitlength = inlength * 8; + + HuffmanTree_init(&tree_ll); + HuffmanTree_init(&tree_d); + + if(btype == 1) getTreeInflateFixed(&tree_ll, &tree_d); + else if(btype == 2) + { + error = getTreeInflateDynamic(&tree_ll, &tree_d, in, bp, inlength); + } + + while(!error) /*decode all symbols until end reached, breaks at end code*/ + { + /*code_ll is literal, length or end code*/ + unsigned code_ll = huffmanDecodeSymbol(in, bp, &tree_ll, inbitlength); + if(code_ll <= 255) /*literal symbol*/ + { + if((*pos) >= out->size) + { + /*reserve more room at once*/ + if(!ucvector_resize(out, ((*pos) + 1) * 2)) ERROR_BREAK(83 /*alloc fail*/); + } + out->data[(*pos)] = (unsigned char)(code_ll); + (*pos)++; + } + else if(code_ll >= FIRST_LENGTH_CODE_INDEX && code_ll <= LAST_LENGTH_CODE_INDEX) /*length code*/ + { + unsigned code_d, distance; + unsigned numextrabits_l, numextrabits_d; /*extra bits for length and distance*/ + size_t start, forward, backward, length; + + /*part 1: get length base*/ + length = LENGTHBASE[code_ll - FIRST_LENGTH_CODE_INDEX]; + + /*part 2: get extra bits and add the value of that to length*/ + numextrabits_l = LENGTHEXTRA[code_ll - FIRST_LENGTH_CODE_INDEX]; + if(*bp >= inbitlength) ERROR_BREAK(51); /*error, bit pointer will jump past memory*/ + length += readBitsFromStream(bp, in, numextrabits_l); + + /*part 3: get distance code*/ + code_d = huffmanDecodeSymbol(in, bp, &tree_d, inbitlength); + if(code_d > 29) + { + if(code_ll == (unsigned)(-1)) /*huffmanDecodeSymbol returns (unsigned)(-1) in case of error*/ + { + /*return error code 10 or 11 depending on the situation that happened in huffmanDecodeSymbol + (10=no endcode, 11=wrong jump outside of tree)*/ + error = (*bp) > inlength * 8 ? 10 : 11; + } + else error = 18; /*error: invalid distance code (30-31 are never used)*/ + break; + } + distance = DISTANCEBASE[code_d]; + + /*part 4: get extra bits from distance*/ + numextrabits_d = DISTANCEEXTRA[code_d]; + if(*bp >= inbitlength) ERROR_BREAK(51); /*error, bit pointer will jump past memory*/ + + distance += readBitsFromStream(bp, in, numextrabits_d); + + /*part 5: fill in all the out[n] values based on the length and dist*/ + start = (*pos); + if(distance > start) ERROR_BREAK(52); /*too long backward distance*/ + backward = start - distance; + if((*pos) + length >= out->size) + { + /*reserve more room at once*/ + if(!ucvector_resize(out, ((*pos) + length) * 2)) ERROR_BREAK(83 /*alloc fail*/); + } + + for(forward = 0; forward < length; forward++) + { + out->data[(*pos)] = out->data[backward]; + (*pos)++; + backward++; + if(backward >= start) backward = start - distance; + } + } + else if(code_ll == 256) + { + break; /*end code, break the loop*/ + } + else /*if(code == (unsigned)(-1))*/ /*huffmanDecodeSymbol returns (unsigned)(-1) in case of error*/ + { + /*return error code 10 or 11 depending on the situation that happened in huffmanDecodeSymbol + (10=no endcode, 11=wrong jump outside of tree)*/ + error = (*bp) > inlength * 8 ? 10 : 11; + break; + } + } + + HuffmanTree_cleanup(&tree_ll); + HuffmanTree_cleanup(&tree_d); + + return error; +} + +static unsigned inflateNoCompression(ucvector* out, const unsigned char* in, size_t* bp, size_t* pos, size_t inlength) +{ + /*go to first boundary of byte*/ + size_t p; + unsigned LEN, NLEN, n, error = 0; + while(((*bp) & 0x7) != 0) (*bp)++; + p = (*bp) / 8; /*byte position*/ + + /*read LEN (2 bytes) and NLEN (2 bytes)*/ + if(p >= inlength - 4) return 52; /*error, bit pointer will jump past memory*/ + LEN = in[p] + 256 * in[p + 1]; p += 2; + NLEN = in[p] + 256 * in[p + 1]; p += 2; + + /*check if 16-bit NLEN is really the one's complement of LEN*/ + if(LEN + NLEN != 65535) return 21; /*error: NLEN is not one's complement of LEN*/ + + if((*pos) + LEN >= out->size) + { + if(!ucvector_resize(out, (*pos) + LEN)) return 83; /*alloc fail*/ + } + + /*read the literal data: LEN bytes are now stored in the out buffer*/ + if(p + LEN > inlength) return 23; /*error: reading outside of in buffer*/ + for(n = 0; n < LEN; n++) out->data[(*pos)++] = in[p++]; + + (*bp) = p * 8; + + return error; +} + +static unsigned lodepng_inflatev(ucvector* out, + const unsigned char* in, size_t insize, + const LodePNGDecompressSettings* settings) +{ + /*bit pointer in the "in" data, current byte is bp >> 3, current bit is bp & 0x7 (from lsb to msb of the byte)*/ + size_t bp = 0; + unsigned BFINAL = 0; + size_t pos = 0; /*byte position in the out buffer*/ + + unsigned error = 0; + + (void)settings; + + while(!BFINAL) + { + unsigned BTYPE; + if(bp + 2 >= insize * 8) return 52; /*error, bit pointer will jump past memory*/ + BFINAL = readBitFromStream(&bp, in); + BTYPE = 1 * readBitFromStream(&bp, in); + BTYPE += 2 * readBitFromStream(&bp, in); + + if(BTYPE == 3) return 20; /*error: invalid BTYPE*/ + else if(BTYPE == 0) error = inflateNoCompression(out, in, &bp, &pos, insize); /*no compression*/ + else error = inflateHuffmanBlock(out, in, &bp, &pos, insize, BTYPE); /*compression, BTYPE 01 or 10*/ + + if(error) return error; + } + + /*Only now we know the true size of out, resize it to that*/ + if(!ucvector_resize(out, pos)) error = 83; /*alloc fail*/ + + return error; +} + +unsigned lodepng_inflate(unsigned char** out, size_t* outsize, + const unsigned char* in, size_t insize, + const LodePNGDecompressSettings* settings) +{ +#if LODEPNG_CUSTOM_ZLIB_DECODER == 2 + if(settings->custom_decoder) + { + return lodepng_custom_inflate(out, outsize, in, insize, settings); + } + else + { +#endif /*LODEPNG_CUSTOM_ZLIB_DECODER == 2*/ + unsigned error; + ucvector v; + ucvector_init_buffer(&v, *out, *outsize); + error = lodepng_inflatev(&v, in, insize, settings); + *out = v.data; + *outsize = v.size; + return error; +#if LODEPNG_CUSTOM_ZLIB_DECODER == 2 + } +#endif /*LODEPNG_CUSTOM_ZLIB_DECODER == 2*/ +} + +#endif /*LODEPNG_COMPILE_DECODER*/ + +#ifdef LODEPNG_COMPILE_ENCODER + +/* ////////////////////////////////////////////////////////////////////////// */ +/* / Deflator (Compressor) / */ +/* ////////////////////////////////////////////////////////////////////////// */ + +static const size_t MAX_SUPPORTED_DEFLATE_LENGTH = 258; + +/*bitlen is the size in bits of the code*/ +static void addHuffmanSymbol(size_t* bp, ucvector* compressed, unsigned code, unsigned bitlen) +{ + addBitsToStreamReversed(bp, compressed, code, bitlen); +} + +/*search the index in the array, that has the largest value smaller than or equal to the given value, +given array must be sorted (if no value is smaller, it returns the size of the given array)*/ +static size_t searchCodeIndex(const unsigned* array, size_t array_size, size_t value) +{ + /*linear search implementation*/ + /*for(size_t i = 1; i < array_size; i++) if(array[i] > value) return i - 1; + return array_size - 1;*/ + + /*binary search implementation (not that much faster) (precondition: array_size > 0)*/ + size_t left = 1; + size_t right = array_size - 1; + while(left <= right) + { + size_t mid = (left + right) / 2; + if(array[mid] <= value) left = mid + 1; /*the value to find is more to the right*/ + else if(array[mid - 1] > value) right = mid - 1; /*the value to find is more to the left*/ + else return mid - 1; + } + return array_size - 1; +} + +static void addLengthDistance(uivector* values, size_t length, size_t distance) +{ + /*values in encoded vector are those used by deflate: + 0-255: literal bytes + 256: end + 257-285: length/distance pair (length code, followed by extra length bits, distance code, extra distance bits) + 286-287: invalid*/ + + unsigned length_code = (unsigned)searchCodeIndex(LENGTHBASE, 29, length); + unsigned extra_length = (unsigned)(length - LENGTHBASE[length_code]); + unsigned dist_code = (unsigned)searchCodeIndex(DISTANCEBASE, 30, distance); + unsigned extra_distance = (unsigned)(distance - DISTANCEBASE[dist_code]); + + uivector_push_back(values, length_code + FIRST_LENGTH_CODE_INDEX); + uivector_push_back(values, extra_length); + uivector_push_back(values, dist_code); + uivector_push_back(values, extra_distance); +} + +static const unsigned HASH_NUM_VALUES = 65536; +static const unsigned HASH_NUM_CHARACTERS = 3; +static const unsigned HASH_SHIFT = 2; +/* +The HASH_NUM_CHARACTERS value is used to make encoding faster by using longer +sequences to generate a hash value from the stream bytes. Setting it to 3 +gives exactly the same compression as the brute force method, since deflate's +run length encoding starts with lengths of 3. Setting it to higher values, +like 6, can make the encoding faster (not always though!), but will cause the +encoding to miss any length between 3 and this value, so that the compression +may be worse (but this can vary too depending on the image, sometimes it is +even a bit better instead). +The HASH_NUM_VALUES is the amount of unique possible hash values that +combinations of bytes can give, the higher it is the more memory is needed, but +if it's too low the advantage of hashing is gone. +*/ + +typedef struct Hash +{ + int* head; /*hash value to head circular pos*/ + int* val; /*circular pos to hash value*/ + /*circular pos to prev circular pos*/ + unsigned short* chain; + unsigned short* zeros; +} Hash; + +static unsigned hash_init(Hash* hash, unsigned windowsize) +{ + unsigned i; + hash->head = (int*)mymalloc(sizeof(int) * HASH_NUM_VALUES); + hash->val = (int*)mymalloc(sizeof(int) * windowsize); + hash->chain = (unsigned short*)mymalloc(sizeof(unsigned short) * windowsize); + hash->zeros = (unsigned short*)mymalloc(sizeof(unsigned short) * windowsize); + + if(!hash->head || !hash->val || !hash->chain || !hash->zeros) return 83; /*alloc fail*/ + + /*initialize hash table*/ + for(i = 0; i < HASH_NUM_VALUES; i++) hash->head[i] = -1; + for(i = 0; i < windowsize; i++) hash->val[i] = -1; + for(i = 0; i < windowsize; i++) hash->chain[i] = i; /*same value as index indicates uninitialized*/ + + return 0; +} + +static void hash_cleanup(Hash* hash) +{ + myfree(hash->head); + myfree(hash->val); + myfree(hash->chain); + myfree(hash->zeros); +} + +static unsigned getHash(const unsigned char* data, size_t size, size_t pos) +{ + unsigned result = 0; + size_t amount, i; + if(pos >= size) return 0; + amount = HASH_NUM_CHARACTERS; + if(pos + amount >= size) amount = size - pos; + for(i = 0; i < amount; i++) result ^= (data[pos + i] << (i * HASH_SHIFT)); + return result % HASH_NUM_VALUES; +} + +static unsigned countZeros(const unsigned char* data, size_t size, size_t pos) +{ + const unsigned char* start = data + pos; + const unsigned char* end = start + MAX_SUPPORTED_DEFLATE_LENGTH; + if(end > data + size) end = data + size; + data = start; + while (data != end && *data == 0) data++; + return data - start; +} + +static void updateHashChain(Hash* hash, + size_t pos, int hashval, unsigned windowsize) +{ + unsigned wpos = pos % windowsize; + hash->val[wpos] = hashval; + if(hash->head[hashval] != -1) + { + hash->chain[wpos] = hash->head[hashval]; + } + hash->head[hashval] = wpos; +} + +/*Enable to use lazy instead of greedy matching. It looks one byte further +to see if that one gives a longer distance. This gives slightly better compression, at the cost +of a speed loss.*/ +#define LAZY_MATCHING + +/* +LZ77-encode the data. Return value is error code. The input are raw bytes, the output +is in the form of unsigned integers with codes representing for example literal bytes, or +length/distance pairs. +It uses a hash table technique to let it encode faster. When doing LZ77 encoding, a +sliding window (of windowsize) is used, and all past bytes in that window can be used as +the "dictionary". A brute force search through all possible distances would be slow, and +this hash technique is one out of several ways to speed this up. +*/ +static unsigned encodeLZ77(uivector* out, Hash* hash, + const unsigned char* in, size_t inpos, size_t insize, unsigned windowsize) +{ + unsigned short numzeros = 0; + int usezeros = windowsize >= 8192; /*for small window size, the 'max chain length' optimization does a better job*/ + unsigned pos, i, error = 0; + + if(!error) + { + unsigned offset; /*the offset represents the distance in LZ77 terminology*/ + unsigned length; +#ifdef LAZY_MATCHING + unsigned lazy = 0; + unsigned lazylength = 0, lazyoffset = 0; +#endif /*LAZY_MATCHING*/ + unsigned hashval; + unsigned current_offset, current_length; + const unsigned char *lastptr, *foreptr, *backptr; + unsigned short hashpos, prevpos; + + for(pos = inpos; pos < insize; pos++) + { + size_t wpos = pos % windowsize; /*position for in 'circular' hash buffers*/ + + hashval = getHash(in, insize, pos); + updateHashChain(hash, pos, hashval, windowsize); + + if(usezeros && hashval == 0) + { + numzeros = countZeros(in, insize, pos); + hash->zeros[wpos] = numzeros; + } + + /*the length and offset found for the current position*/ + length = 0; + offset = 0; + + prevpos = hash->head[hashval]; + hashpos = hash->chain[prevpos]; + + lastptr = &in[insize < pos + MAX_SUPPORTED_DEFLATE_LENGTH ? insize : pos + MAX_SUPPORTED_DEFLATE_LENGTH]; + + /*search for the longest string*/ + if(hash->val[wpos] == (int)hashval) + { + /*for large window lengths, assume the user wants no compression loss. Otherwise, max hash chain length speedup.*/ + unsigned maxchainlength = windowsize >= 8192 ? windowsize : windowsize / 8; + for(;;) + { + /*stop when went completely around the circular buffer*/ + if(prevpos < wpos && hashpos > prevpos && hashpos <= wpos) break; + if(prevpos > wpos && (hashpos <= wpos || hashpos > prevpos)) break; + if(maxchainlength-- == 0) break; + + current_offset = hashpos <= wpos ? wpos - hashpos : wpos - hashpos + windowsize; + if(current_offset > 0) + { + /*test the next characters*/ + foreptr = &in[pos]; + backptr = &in[pos - current_offset]; + + /*common case in PNGs is lots of zeros. Quickly skip over them as a speedup*/ + if(usezeros && hashval == 0 && hash->val[hashpos] == 0 /*hashval[hashpos] may be out of date*/) + { + unsigned short skip = hash->zeros[hashpos]; + if(skip > numzeros) skip = numzeros; + backptr += skip; + foreptr += skip; + } + + /* multiple checks at once per array bounds check */ + while(foreptr != lastptr && *backptr == *foreptr) /*maximum supported length by deflate is max length*/ + { + ++backptr; + ++foreptr; + } + current_length = (unsigned)(foreptr - &in[pos]); + + if(current_length > length) + { + length = current_length; /*the longest length*/ + offset = current_offset; /*the offset that is related to this longest length*/ + /*jump out once a length of max length is found (speed gain)*/ + if(current_length == MAX_SUPPORTED_DEFLATE_LENGTH) break; + } + } + + if(hashpos == hash->chain[hashpos]) break; + + prevpos = hashpos; + hashpos = hash->chain[hashpos]; + } + } + +#ifdef LAZY_MATCHING + if(!lazy && length >= 3 && length < MAX_SUPPORTED_DEFLATE_LENGTH) + { + lazy = 1; + lazylength = length; + lazyoffset = offset; + continue; + } + if(lazy) + { + lazy = 0; + if(pos == 0) ERROR_BREAK(81); + if(length > lazylength + 1) + { + /*push the previous character as literal*/ + if(!uivector_push_back(out, in[pos - 1])) ERROR_BREAK(83 /*alloc fail*/); + } + else + { + length = lazylength; + offset = lazyoffset; + hash->head[hashval] = -1; /*the same hashchain update will be done, this ensures no wrong alteration*/ + pos--; + } + } +#endif /*LAZY_MATCHING*/ + + if(length >= 3 && offset > windowsize) ERROR_BREAK(86 /*too big (or overflown negative) offset*/); + + + /**encode it as length/distance pair or literal value**/ + if(length < 3) /*only lengths of 3 or higher are supported as length/distance pair*/ + { + if(!uivector_push_back(out, in[pos])) ERROR_BREAK(83 /*alloc fail*/); + } + else + { + if(length == 3 && offset > 2048) + { + /*compensate for the fact that longer offsets have more extra bits, a + length of only 3 may be not worth it then*/ + if(!uivector_push_back(out, in[pos + 0])) ERROR_BREAK(83 /*alloc fail*/); + if(!uivector_push_back(out, in[pos + 1])) ERROR_BREAK(83 /*alloc fail*/); + if(!uivector_push_back(out, in[pos + 2])) ERROR_BREAK(83 /*alloc fail*/); + } + else + { + addLengthDistance(out, length, offset); + } + for(i = 1; i < length; i++) + { + pos++; + hashval = getHash(in, insize, pos); + updateHashChain(hash, pos, hashval, windowsize); + if(usezeros && hashval == 0) + { + hash->zeros[pos % windowsize] = countZeros(in, insize, pos); + } + } + } + + } /*end of the loop through each character of input*/ + } /*end of "if(!error)"*/ + + return error; +} + +/* /////////////////////////////////////////////////////////////////////////// */ + +static unsigned deflateNoCompression(ucvector* out, const unsigned char* data, size_t datasize) +{ + /*non compressed deflate block data: 1 bit BFINAL,2 bits BTYPE,(5 bits): it jumps to start of next byte, + 2 bytes LEN, 2 bytes NLEN, LEN bytes literal DATA*/ + + size_t i, j, numdeflateblocks = (datasize + 65534) / 65535; + unsigned datapos = 0; + for(i = 0; i < numdeflateblocks; i++) + { + unsigned BFINAL, BTYPE, LEN, NLEN; + unsigned char firstbyte; + + BFINAL = (i == numdeflateblocks - 1); + BTYPE = 0; + + firstbyte = (unsigned char)(BFINAL + ((BTYPE & 1) << 1) + ((BTYPE & 2) << 1)); + ucvector_push_back(out, firstbyte); + + LEN = 65535; + if(datasize - datapos < 65535) LEN = (unsigned)datasize - datapos; + NLEN = 65535 - LEN; + + ucvector_push_back(out, (unsigned char)(LEN % 256)); + ucvector_push_back(out, (unsigned char)(LEN / 256)); + ucvector_push_back(out, (unsigned char)(NLEN % 256)); + ucvector_push_back(out, (unsigned char)(NLEN / 256)); + + /*Decompressed data*/ + for(j = 0; j < 65535 && datapos < datasize; j++) + { + ucvector_push_back(out, data[datapos++]); + } + } + + return 0; +} + +/* +write the lz77-encoded data, which has lit, len and dist codes, to compressed stream using huffman trees. +tree_ll: the tree for lit and len codes. +tree_d: the tree for distance codes. +*/ +static void writeLZ77data(size_t* bp, ucvector* out, const uivector* lz77_encoded, + const HuffmanTree* tree_ll, const HuffmanTree* tree_d) +{ + size_t i = 0; + for(i = 0; i < lz77_encoded->size; i++) + { + unsigned val = lz77_encoded->data[i]; + addHuffmanSymbol(bp, out, HuffmanTree_getCode(tree_ll, val), HuffmanTree_getLength(tree_ll, val)); + if(val > 256) /*for a length code, 3 more things have to be added*/ + { + unsigned length_index = val - FIRST_LENGTH_CODE_INDEX; + unsigned n_length_extra_bits = LENGTHEXTRA[length_index]; + unsigned length_extra_bits = lz77_encoded->data[++i]; + + unsigned distance_code = lz77_encoded->data[++i]; + + unsigned distance_index = distance_code; + unsigned n_distance_extra_bits = DISTANCEEXTRA[distance_index]; + unsigned distance_extra_bits = lz77_encoded->data[++i]; + + addBitsToStream(bp, out, length_extra_bits, n_length_extra_bits); + addHuffmanSymbol(bp, out, HuffmanTree_getCode(tree_d, distance_code), + HuffmanTree_getLength(tree_d, distance_code)); + addBitsToStream(bp, out, distance_extra_bits, n_distance_extra_bits); + } + } +} + +/*Deflate for a block of type "dynamic", that is, with freely, optimally, created huffman trees*/ +static unsigned deflateDynamic(ucvector* out, size_t* bp, Hash* hash, + const unsigned char* data, size_t datapos, size_t dataend, + const LodePNGCompressSettings* settings, int final) +{ + unsigned error = 0; + + /* + A block is compressed as follows: The PNG data is lz77 encoded, resulting in + literal bytes and length/distance pairs. This is then huffman compressed with + two huffman trees. One huffman tree is used for the lit and len values ("ll"), + another huffman tree is used for the dist values ("d"). These two trees are + stored using their code lengths, and to compress even more these code lengths + are also run-length encoded and huffman compressed. This gives a huffman tree + of code lengths "cl". The code lenghts used to describe this third tree are + the code length code lengths ("clcl"). + */ + + /*The lz77 encoded data, represented with integers since there will also be length and distance codes in it*/ + uivector lz77_encoded; + HuffmanTree tree_ll; /*tree for lit,len values*/ + HuffmanTree tree_d; /*tree for distance codes*/ + HuffmanTree tree_cl; /*tree for encoding the code lengths representing tree_ll and tree_d*/ + uivector frequencies_ll; /*frequency of lit,len codes*/ + uivector frequencies_d; /*frequency of dist codes*/ + uivector frequencies_cl; /*frequency of code length codes*/ + uivector bitlen_lld; /*lit,len,dist code lenghts (int bits), literally (without repeat codes).*/ + uivector bitlen_lld_e; /*bitlen_lld encoded with repeat codes (this is a rudemtary run length compression)*/ + /*bitlen_cl is the code length code lengths ("clcl"). The bit lengths of codes to represent tree_cl + (these are written as is in the file, it would be crazy to compress these using yet another huffman + tree that needs to be represented by yet another set of code lengths)*/ + uivector bitlen_cl; + size_t datasize = dataend - datapos; + + /* + Due to the huffman compression of huffman tree representations ("two levels"), there are some anologies: + bitlen_lld is to tree_cl what data is to tree_ll and tree_d. + bitlen_lld_e is to bitlen_lld what lz77_encoded is to data. + bitlen_cl is to bitlen_lld_e what bitlen_lld is to lz77_encoded. + */ + + unsigned BFINAL = final; + size_t numcodes_ll, numcodes_d, i; + unsigned HLIT, HDIST, HCLEN; + + uivector_init(&lz77_encoded); + HuffmanTree_init(&tree_ll); + HuffmanTree_init(&tree_d); + HuffmanTree_init(&tree_cl); + uivector_init(&frequencies_ll); + uivector_init(&frequencies_d); + uivector_init(&frequencies_cl); + uivector_init(&bitlen_lld); + uivector_init(&bitlen_lld_e); + uivector_init(&bitlen_cl); + + /*This while loop is never loops due to a break at the end, it is here to + allow breaking out of it to the cleanup phase on error conditions.*/ + while(!error) + { + if(settings->use_lz77) + { + error = encodeLZ77(&lz77_encoded, hash, data, datapos, dataend, settings->windowsize); /*LZ77 encoded*/ + if(error) break; + } + else + { + if(!uivector_resize(&lz77_encoded, datasize)) ERROR_BREAK(83 /*alloc fail*/); + for(i = datapos; i < dataend; i++) lz77_encoded.data[i] = data[i]; /*no LZ77, but still will be Huffman compressed*/ + } + + if(!uivector_resizev(&frequencies_ll, 286, 0)) ERROR_BREAK(83 /*alloc fail*/); + if(!uivector_resizev(&frequencies_d, 30, 0)) ERROR_BREAK(83 /*alloc fail*/); + + /*Count the frequencies of lit, len and dist codes*/ + for(i = 0; i < lz77_encoded.size; i++) + { + unsigned symbol = lz77_encoded.data[i]; + frequencies_ll.data[symbol]++; + if(symbol > 256) + { + unsigned dist = lz77_encoded.data[i + 2]; + frequencies_d.data[dist]++; + i += 3; + } + } + frequencies_ll.data[256] = 1; /*there will be exactly 1 end code, at the end of the block*/ + + /*Make both huffman trees, one for the lit and len codes, one for the dist codes*/ + error = HuffmanTree_makeFromFrequencies(&tree_ll, frequencies_ll.data, frequencies_ll.size, 15); + if(error) break; + error = HuffmanTree_makeFromFrequencies(&tree_d, frequencies_d.data, frequencies_d.size, 15); + if(error) break; + + numcodes_ll = tree_ll.numcodes; if(numcodes_ll > 286) numcodes_ll = 286; + numcodes_d = tree_d.numcodes; if(numcodes_d > 30) numcodes_d = 30; + /*store the code lengths of both generated trees in bitlen_lld*/ + for(i = 0; i < numcodes_ll; i++) uivector_push_back(&bitlen_lld, HuffmanTree_getLength(&tree_ll, (unsigned)i)); + for(i = 0; i < numcodes_d; i++) uivector_push_back(&bitlen_lld, HuffmanTree_getLength(&tree_d, (unsigned)i)); + + /*run-length compress bitlen_ldd into bitlen_lld_e by using repeat codes 16 (copy length 3-6 times), + 17 (3-10 zeroes), 18 (11-138 zeroes)*/ + for(i = 0; i < (unsigned)bitlen_lld.size; i++) + { + unsigned j = 0; /*amount of repititions*/ + while(i + j + 1 < (unsigned)bitlen_lld.size && bitlen_lld.data[i + j + 1] == bitlen_lld.data[i]) j++; + + if(bitlen_lld.data[i] == 0 && j >= 2) /*repeat code for zeroes*/ + { + j++; /*include the first zero*/ + if(j <= 10) /*repeat code 17 supports max 10 zeroes*/ + { + uivector_push_back(&bitlen_lld_e, 17); + uivector_push_back(&bitlen_lld_e, j - 3); + } + else /*repeat code 18 supports max 138 zeroes*/ + { + if(j > 138) j = 138; + uivector_push_back(&bitlen_lld_e, 18); + uivector_push_back(&bitlen_lld_e, j - 11); + } + i += (j - 1); + } + else if(j >= 3) /*repeat code for value other than zero*/ + { + size_t k; + unsigned num = j / 6, rest = j % 6; + uivector_push_back(&bitlen_lld_e, bitlen_lld.data[i]); + for(k = 0; k < num; k++) + { + uivector_push_back(&bitlen_lld_e, 16); + uivector_push_back(&bitlen_lld_e, 6 - 3); + } + if(rest >= 3) + { + uivector_push_back(&bitlen_lld_e, 16); + uivector_push_back(&bitlen_lld_e, rest - 3); + } + else j -= rest; + i += j; + } + else /*too short to benefit from repeat code*/ + { + uivector_push_back(&bitlen_lld_e, bitlen_lld.data[i]); + } + } + + /*generate tree_cl, the huffmantree of huffmantrees*/ + + if(!uivector_resizev(&frequencies_cl, NUM_CODE_LENGTH_CODES, 0)) ERROR_BREAK(83 /*alloc fail*/); + for(i = 0; i < bitlen_lld_e.size; i++) + { + frequencies_cl.data[bitlen_lld_e.data[i]]++; + /*after a repeat code come the bits that specify the number of repetitions, + those don't need to be in the frequencies_cl calculation*/ + if(bitlen_lld_e.data[i] >= 16) i++; + } + + error = HuffmanTree_makeFromFrequencies(&tree_cl, frequencies_cl.data, frequencies_cl.size, 7); + if(error) break; + + if(!uivector_resize(&bitlen_cl, NUM_CODE_LENGTH_CODES)) ERROR_BREAK(83 /*alloc fail*/); + for(i = 0; i < NUM_CODE_LENGTH_CODES; i++) + { + /*lenghts of code length tree is in the order as specified by deflate*/ + bitlen_cl.data[i] = HuffmanTree_getLength(&tree_cl, CLCL_ORDER[i]); + } + while(bitlen_cl.data[bitlen_cl.size - 1] == 0 && bitlen_cl.size > 4) + { + /*remove zeros at the end, but minimum size must be 4*/ + if(!uivector_resize(&bitlen_cl, bitlen_cl.size - 1)) ERROR_BREAK(83 /*alloc fail*/); + } + if(error) break; + + /* + Write everything into the output + + After the BFINAL and BTYPE, the dynamic block consists out of the following: + - 5 bits HLIT, 5 bits HDIST, 4 bits HCLEN + - (HCLEN+4)*3 bits code lengths of code length alphabet + - HLIT + 257 code lenghts of lit/length alphabet (encoded using the code length + alphabet, + possible repetition codes 16, 17, 18) + - HDIST + 1 code lengths of distance alphabet (encoded using the code length + alphabet, + possible repetition codes 16, 17, 18) + - compressed data + - 256 (end code) + */ + + /*Write block type*/ + addBitToStream(bp, out, BFINAL); + addBitToStream(bp, out, 0); /*first bit of BTYPE "dynamic"*/ + addBitToStream(bp, out, 1); /*second bit of BTYPE "dynamic"*/ + + /*write the HLIT, HDIST and HCLEN values*/ + HLIT = (unsigned)(numcodes_ll - 257); + HDIST = (unsigned)(numcodes_d - 1); + HCLEN = (unsigned)bitlen_cl.size - 4; + addBitsToStream(bp, out, HLIT, 5); + addBitsToStream(bp, out, HDIST, 5); + addBitsToStream(bp, out, HCLEN, 4); + + /*write the code lenghts of the code length alphabet*/ + for(i = 0; i < HCLEN + 4; i++) addBitsToStream(bp, out, bitlen_cl.data[i], 3); + + /*write the lenghts of the lit/len AND the dist alphabet*/ + for(i = 0; i < bitlen_lld_e.size; i++) + { + addHuffmanSymbol(bp, out, HuffmanTree_getCode(&tree_cl, bitlen_lld_e.data[i]), + HuffmanTree_getLength(&tree_cl, bitlen_lld_e.data[i])); + /*extra bits of repeat codes*/ + if(bitlen_lld_e.data[i] == 16) addBitsToStream(bp, out, bitlen_lld_e.data[++i], 2); + else if(bitlen_lld_e.data[i] == 17) addBitsToStream(bp, out, bitlen_lld_e.data[++i], 3); + else if(bitlen_lld_e.data[i] == 18) addBitsToStream(bp, out, bitlen_lld_e.data[++i], 7); + } + + /*write the compressed data symbols*/ + writeLZ77data(bp, out, &lz77_encoded, &tree_ll, &tree_d); + /*error: the length of the end code 256 must be larger than 0*/ + if(HuffmanTree_getLength(&tree_ll, 256) == 0) ERROR_BREAK(64); + + /*write the end code*/ + addHuffmanSymbol(bp, out, HuffmanTree_getCode(&tree_ll, 256), HuffmanTree_getLength(&tree_ll, 256)); + + break; /*end of error-while*/ + } + + /*cleanup*/ + uivector_cleanup(&lz77_encoded); + HuffmanTree_cleanup(&tree_ll); + HuffmanTree_cleanup(&tree_d); + HuffmanTree_cleanup(&tree_cl); + uivector_cleanup(&frequencies_ll); + uivector_cleanup(&frequencies_d); + uivector_cleanup(&frequencies_cl); + uivector_cleanup(&bitlen_lld_e); + uivector_cleanup(&bitlen_lld); + uivector_cleanup(&bitlen_cl); + + return error; +} + +static unsigned deflateFixed(ucvector* out, size_t* bp, Hash* hash, + const unsigned char* data, + size_t datapos, size_t dataend, + const LodePNGCompressSettings* settings, int final) +{ + HuffmanTree tree_ll; /*tree for literal values and length codes*/ + HuffmanTree tree_d; /*tree for distance codes*/ + + unsigned BFINAL = final; + unsigned error = 0; + size_t i; + + HuffmanTree_init(&tree_ll); + HuffmanTree_init(&tree_d); + + generateFixedLitLenTree(&tree_ll); + generateFixedDistanceTree(&tree_d); + + addBitToStream(bp, out, BFINAL); + addBitToStream(bp, out, 1); /*first bit of BTYPE*/ + addBitToStream(bp, out, 0); /*second bit of BTYPE*/ + + if(settings->use_lz77) /*LZ77 encoded*/ + { + uivector lz77_encoded; + uivector_init(&lz77_encoded); + error = encodeLZ77(&lz77_encoded, hash, data, datapos, dataend, settings->windowsize); + if(!error) writeLZ77data(bp, out, &lz77_encoded, &tree_ll, &tree_d); + uivector_cleanup(&lz77_encoded); + } + else /*no LZ77, but still will be Huffman compressed*/ + { + for(i = datapos; i < dataend; i++) + { + addHuffmanSymbol(bp, out, HuffmanTree_getCode(&tree_ll, data[i]), HuffmanTree_getLength(&tree_ll, data[i])); + } + } + /*add END code*/ + if(!error) addHuffmanSymbol(bp, out, HuffmanTree_getCode(&tree_ll, 256), HuffmanTree_getLength(&tree_ll, 256)); + + /*cleanup*/ + HuffmanTree_cleanup(&tree_ll); + HuffmanTree_cleanup(&tree_d); + + return error; +} + +static unsigned lodepng_deflatev(ucvector* out, const unsigned char* in, size_t insize, + const LodePNGCompressSettings* settings) +{ +#if LODEPNG_CUSTOM_ZLIB_ENCODER == 2 + if(settings->custom_encoder) + { + unsigned char** out2 = &out->data; + size_t* outsize = &out->size; + + unsigned error = lodepng_custom_deflate(out2, outsize, in, insize, settings); + + if(!error) ucvector_init_buffer(out, *out2, *outsize); + return error; + } + else + { +#endif /*LODEPNG_CUSTOM_ZLIB_ENCODER == 2*/ + unsigned error = 0; + size_t i, blocksize, numdeflateblocks; + size_t bp = 0; /*the bit pointer*/ + Hash hash; + + if(settings->btype > 2) return 61; + + if(settings->btype == 0) return deflateNoCompression(out, in, insize); + + if(settings->btype == 1) blocksize = insize; + else /*if(settings->btype == 2)*/ + { + blocksize = insize / 8 + 8; + if(blocksize < 65535) blocksize = 65535; + } + + numdeflateblocks = (insize + blocksize - 1) / blocksize; + if(numdeflateblocks == 0) numdeflateblocks = 1; + + error = hash_init(&hash, settings->windowsize); + if(error) return error; + + for(i = 0; i < numdeflateblocks && !error; i++) + { + int final = i == numdeflateblocks - 1; + size_t start = i * blocksize; + size_t end = start + blocksize; + if(end > insize) end = insize; + + if(settings->btype == 1) error = deflateFixed(out, &bp, &hash, in, start, end, settings, final); + else if(settings->btype == 2) error = deflateDynamic(out, &bp, &hash, in, start, end, settings, final); + } + + hash_cleanup(&hash); + + return error; +#if LODEPNG_CUSTOM_ZLIB_ENCODER == 2 + } +#endif /*LODEPNG_CUSTOM_ZLIB_ENCODER == 2*/ +} + +unsigned lodepng_deflate(unsigned char** out, size_t* outsize, + const unsigned char* in, size_t insize, + const LodePNGCompressSettings* settings) +{ + unsigned error; + ucvector v; + ucvector_init_buffer(&v, *out, *outsize); + error = lodepng_deflatev(&v, in, insize, settings); + *out = v.data; + *outsize = v.size; + return error; +} + +#endif /*LODEPNG_COMPILE_DECODER*/ + +/* ////////////////////////////////////////////////////////////////////////// */ +/* / Adler32 */ +/* ////////////////////////////////////////////////////////////////////////// */ + +static unsigned update_adler32(unsigned adler, const unsigned char* data, unsigned len) +{ + unsigned s1 = adler & 0xffff; + unsigned s2 = (adler >> 16) & 0xffff; + + while(len > 0) + { + /*at least 5550 sums can be done before the sums overflow, saving a lot of module divisions*/ + unsigned amount = len > 5550 ? 5550 : len; + len -= amount; + while(amount > 0) + { + s1 = (s1 + *data++); + s2 = (s2 + s1); + amount--; + } + s1 %= 65521; + s2 %= 65521; + } + + return (s2 << 16) | s1; +} + +/*Return the adler32 of the bytes data[0..len-1]*/ +static unsigned adler32(const unsigned char* data, unsigned len) +{ + return update_adler32(1L, data, len); +} + +/* ////////////////////////////////////////////////////////////////////////// */ +/* / Zlib / */ +/* ////////////////////////////////////////////////////////////////////////// */ + +#ifdef LODEPNG_COMPILE_DECODER + +unsigned lodepng_zlib_decompress(unsigned char** out, size_t* outsize, const unsigned char* in, + size_t insize, const LodePNGDecompressSettings* settings) +{ +#if LODEPNG_CUSTOM_ZLIB_DECODER == 1 + if(settings->custom_decoder) + { + return lodepng_custom_zlib_decompress(out, outsize, in, insize, settings); + } + else + { +#endif /*LODEPNG_CUSTOM_ZLIB_DECODER == 1*/ + unsigned error = 0; + unsigned CM, CINFO, FDICT; + + if(insize < 2) return 53; /*error, size of zlib data too small*/ + /*read information from zlib header*/ + if((in[0] * 256 + in[1]) % 31 != 0) + { + /*error: 256 * in[0] + in[1] must be a multiple of 31, the FCHECK value is supposed to be made that way*/ + return 24; + } + + CM = in[0] & 15; + CINFO = (in[0] >> 4) & 15; + /*FCHECK = in[1] & 31;*/ /*FCHECK is already tested above*/ + FDICT = (in[1] >> 5) & 1; + /*FLEVEL = (in[1] >> 6) & 3;*/ /*FLEVEL is not used here*/ + + if(CM != 8 || CINFO > 7) + { + /*error: only compression method 8: inflate with sliding window of 32k is supported by the PNG spec*/ + return 25; + } + if(FDICT != 0) + { + /*error: the specification of PNG says about the zlib stream: + "The additional flags shall not specify a preset dictionary."*/ + return 26; + } + + error = lodepng_inflate(out, outsize, in + 2, insize - 2, settings); + if(error) return error; + + if(!settings->ignore_adler32) + { + unsigned ADLER32 = lodepng_read32bitInt(&in[insize - 4]); + unsigned checksum = adler32(*out, (unsigned)(*outsize)); + if(checksum != ADLER32) return 58; /*error, adler checksum not correct, data must be corrupted*/ + } + + return 0; /*no error*/ +#if LODEPNG_CUSTOM_ZLIB_DECODER == 1 + } +#endif /*LODEPNG_CUSTOM_ZLIB_DECODER == 1*/ +} + +#endif /*LODEPNG_COMPILE_DECODER*/ + +#ifdef LODEPNG_COMPILE_ENCODER + +unsigned lodepng_zlib_compress(unsigned char** out, size_t* outsize, const unsigned char* in, + size_t insize, const LodePNGCompressSettings* settings) +{ +#if LODEPNG_CUSTOM_ZLIB_ENCODER == 1 + if(settings->custom_encoder) + { + return lodepng_custom_zlib_compress(out, outsize, in, insize, settings); + } + else + { +#endif /*LODEPNG_CUSTOM_ZLIB_ENCODER == 1*/ + /*initially, *out must be NULL and outsize 0, if you just give some random *out + that's pointing to a non allocated buffer, this'll crash*/ + ucvector deflatedata, outv; + size_t i; + unsigned error; + + unsigned ADLER32; + /*zlib data: 1 byte CMF (CM+CINFO), 1 byte FLG, deflate data, 4 byte ADLER32 checksum of the Decompressed data*/ + unsigned CMF = 120; /*0b01111000: CM 8, CINFO 7. With CINFO 7, any window size up to 32768 can be used.*/ + unsigned FLEVEL = 0; + unsigned FDICT = 0; + unsigned CMFFLG = 256 * CMF + FDICT * 32 + FLEVEL * 64; + unsigned FCHECK = 31 - CMFFLG % 31; + CMFFLG += FCHECK; + + /*ucvector-controlled version of the output buffer, for dynamic array*/ + ucvector_init_buffer(&outv, *out, *outsize); + + ucvector_push_back(&outv, (unsigned char)(CMFFLG / 256)); + ucvector_push_back(&outv, (unsigned char)(CMFFLG % 256)); + + ucvector_init(&deflatedata); + error = lodepng_deflatev(&deflatedata, in, insize, settings); + + if(!error) + { + ADLER32 = adler32(in, (unsigned)insize); + for(i = 0; i < deflatedata.size; i++) ucvector_push_back(&outv, deflatedata.data[i]); + ucvector_cleanup(&deflatedata); + lodepng_add32bitInt(&outv, ADLER32); + } + + *out = outv.data; + *outsize = outv.size; + + return error; +#if LODEPNG_CUSTOM_ZLIB_ENCODER == 1 + } +#endif /*LODEPNG_CUSTOM_ZLIB_ENCODER == 1*/ +} + +#endif /*LODEPNG_COMPILE_ENCODER*/ + +#else /*no LODEPNG_COMPILE_ZLIB*/ + +#ifdef LODEPNG_COMPILE_DECODER +static unsigned lodepng_zlib_decompress(unsigned char** out, size_t* outsize, const unsigned char* in, + size_t insize, const LodePNGDecompressSettings* settings) +{ + return lodepng_custom_zlib_decompress(out, outsize, in, insize, settings); +} +#endif /*LODEPNG_COMPILE_DECODER*/ +#ifdef LODEPNG_COMPILE_ENCODER +static unsigned lodepng_zlib_compress(unsigned char** out, size_t* outsize, const unsigned char* in, + size_t insize, const LodePNGCompressSettings* settings) +{ + return lodepng_custom_zlib_compress(out, outsize, in, insize, settings); +} +#endif /*LODEPNG_COMPILE_ENCODER*/ + +#endif /*LODEPNG_COMPILE_ZLIB*/ + +/* ////////////////////////////////////////////////////////////////////////// */ + +#ifdef LODEPNG_COMPILE_ENCODER + +/*this is a good tradeoff between speed and compression ratio*/ +#define DEFAULT_WINDOWSIZE 2048 + +void lodepng_compress_settings_init(LodePNGCompressSettings* settings) +{ + /*compress with dynamic huffman tree (not in the mathematical sense, just not the predefined one)*/ + settings->btype = 2; + settings->use_lz77 = 1; + settings->windowsize = DEFAULT_WINDOWSIZE; +#if LODEPNG_CUSTOM_ZLIB_ENCODER == 0 + settings->custom_encoder = 0; +#else + settings->custom_encoder = 1; +#endif +} + +#if LODEPNG_CUSTOM_ZLIB_ENCODER == 0 +const LodePNGCompressSettings lodepng_default_compress_settings = {2, 1, DEFAULT_WINDOWSIZE, 0}; +#else +const LodePNGCompressSettings lodepng_default_compress_settings = {2, 1, DEFAULT_WINDOWSIZE, 1}; +#endif + + +#endif /*LODEPNG_COMPILE_ENCODER*/ + +#ifdef LODEPNG_COMPILE_DECODER + +void lodepng_decompress_settings_init(LodePNGDecompressSettings* settings) +{ + settings->ignore_adler32 = 0; +#if LODEPNG_CUSTOM_ZLIB_DECODER == 0 + settings->custom_decoder = 0; +#else + settings->custom_decoder = 1; +#endif +} + +#if LODEPNG_CUSTOM_ZLIB_DECODER == 0 +const LodePNGDecompressSettings lodepng_default_decompress_settings = {0, 0}; +#else +const LodePNGDecompressSettings lodepng_default_decompress_settings = {0, 1}; +#endif + +#endif /*LODEPNG_COMPILE_DECODER*/ + +/* ////////////////////////////////////////////////////////////////////////// */ +/* ////////////////////////////////////////////////////////////////////////// */ +/* // End of Zlib related code. Begin of PNG related code. // */ +/* ////////////////////////////////////////////////////////////////////////// */ +/* ////////////////////////////////////////////////////////////////////////// */ + +#ifdef LODEPNG_COMPILE_PNG + +/* ////////////////////////////////////////////////////////////////////////// */ +/* / CRC32 / */ +/* ////////////////////////////////////////////////////////////////////////// */ + +static unsigned Crc32_crc_table_computed = 0; +static unsigned Crc32_crc_table[256]; + +/*Make the table for a fast CRC.*/ +static void Crc32_make_crc_table(void) +{ + unsigned c, k, n; + for(n = 0; n < 256; n++) + { + c = n; + for(k = 0; k < 8; k++) + { + if(c & 1) c = 0xedb88320L ^ (c >> 1); + else c = c >> 1; + } + Crc32_crc_table[n] = c; + } + Crc32_crc_table_computed = 1; +} + +/*Update a running CRC with the bytes buf[0..len-1]--the CRC should be +initialized to all 1's, and the transmitted value is the 1's complement of the +final running CRC (see the crc() routine below).*/ +static unsigned Crc32_update_crc(const unsigned char* buf, unsigned crc, size_t len) +{ + unsigned c = crc; + size_t n; + + if(!Crc32_crc_table_computed) Crc32_make_crc_table(); + for(n = 0; n < len; n++) + { + c = Crc32_crc_table[(c ^ buf[n]) & 0xff] ^ (c >> 8); + } + return c; +} + +/*Return the CRC of the bytes buf[0..len-1].*/ +unsigned lodepng_crc32(const unsigned char* buf, size_t len) +{ + return Crc32_update_crc(buf, 0xffffffffL, len) ^ 0xffffffffL; +} + +/* ////////////////////////////////////////////////////////////////////////// */ +/* / Reading and writing single bits and bytes from/to stream for LodePNG / */ +/* ////////////////////////////////////////////////////////////////////////// */ + +static unsigned char readBitFromReversedStream(size_t* bitpointer, const unsigned char* bitstream) +{ + unsigned char result = (unsigned char)((bitstream[(*bitpointer) >> 3] >> (7 - ((*bitpointer) & 0x7))) & 1); + (*bitpointer)++; + return result; +} + +static unsigned readBitsFromReversedStream(size_t* bitpointer, const unsigned char* bitstream, size_t nbits) +{ + unsigned result = 0; + size_t i; + for(i = nbits - 1; i < nbits; i--) + { + result += (unsigned)readBitFromReversedStream(bitpointer, bitstream) << i; + } + return result; +} + +#ifdef LODEPNG_COMPILE_DECODER +static void setBitOfReversedStream0(size_t* bitpointer, unsigned char* bitstream, unsigned char bit) +{ + /*the current bit in bitstream must be 0 for this to work*/ + if(bit) + { + /*earlier bit of huffman code is in a lesser significant bit of an earlier byte*/ + bitstream[(*bitpointer) >> 3] |= (bit << (7 - ((*bitpointer) & 0x7))); + } + (*bitpointer)++; +} +#endif /*LODEPNG_COMPILE_DECODER*/ + +static void setBitOfReversedStream(size_t* bitpointer, unsigned char* bitstream, unsigned char bit) +{ + /*the current bit in bitstream may be 0 or 1 for this to work*/ + if(bit == 0) bitstream[(*bitpointer) >> 3] &= (unsigned char)(~(1 << (7 - ((*bitpointer) & 0x7)))); + else bitstream[(*bitpointer) >> 3] |= (1 << (7 - ((*bitpointer) & 0x7))); + (*bitpointer)++; +} + +/* ////////////////////////////////////////////////////////////////////////// */ +/* / PNG chunks / */ +/* ////////////////////////////////////////////////////////////////////////// */ + +unsigned lodepng_chunk_length(const unsigned char* chunk) +{ + return lodepng_read32bitInt(&chunk[0]); +} + +void lodepng_chunk_type(char type[5], const unsigned char* chunk) +{ + unsigned i; + for(i = 0; i < 4; i++) type[i] = chunk[4 + i]; + type[4] = 0; /*null termination char*/ +} + +unsigned char lodepng_chunk_type_equals(const unsigned char* chunk, const char* type) +{ + if(strlen(type) != 4) return 0; + return (chunk[4] == type[0] && chunk[5] == type[1] && chunk[6] == type[2] && chunk[7] == type[3]); +} + +unsigned char lodepng_chunk_ancillary(const unsigned char* chunk) +{ + return((chunk[4] & 32) != 0); +} + +unsigned char lodepng_chunk_private(const unsigned char* chunk) +{ + return((chunk[6] & 32) != 0); +} + +unsigned char lodepng_chunk_safetocopy(const unsigned char* chunk) +{ + return((chunk[7] & 32) != 0); +} + +unsigned char* lodepng_chunk_data(unsigned char* chunk) +{ + return &chunk[8]; +} + +const unsigned char* lodepng_chunk_data_const(const unsigned char* chunk) +{ + return &chunk[8]; +} + +unsigned lodepng_chunk_check_crc(const unsigned char* chunk) +{ + unsigned length = lodepng_chunk_length(chunk); + unsigned CRC = lodepng_read32bitInt(&chunk[length + 8]); + /*the CRC is taken of the data and the 4 chunk type letters, not the length*/ + unsigned checksum = lodepng_crc32(&chunk[4], length + 4); + if(CRC != checksum) return 1; + else return 0; +} + +void lodepng_chunk_generate_crc(unsigned char* chunk) +{ + unsigned length = lodepng_chunk_length(chunk); + unsigned CRC = lodepng_crc32(&chunk[4], length + 4); + lodepng_set32bitInt(chunk + 8 + length, CRC); +} + +unsigned char* lodepng_chunk_next(unsigned char* chunk) +{ + unsigned total_chunk_length = lodepng_chunk_length(chunk) + 12; + return &chunk[total_chunk_length]; +} + +const unsigned char* lodepng_chunk_next_const(const unsigned char* chunk) +{ + unsigned total_chunk_length = lodepng_chunk_length(chunk) + 12; + return &chunk[total_chunk_length]; +} + +unsigned lodepng_chunk_append(unsigned char** out, size_t* outlength, const unsigned char* chunk) +{ + unsigned i; + unsigned total_chunk_length = lodepng_chunk_length(chunk) + 12; + unsigned char *chunk_start, *new_buffer; + size_t new_length = (*outlength) + total_chunk_length; + if(new_length < total_chunk_length || new_length < (*outlength)) return 77; /*integer overflow happened*/ + + new_buffer = (unsigned char*)myrealloc(*out, new_length); + if(!new_buffer) return 83; /*alloc fail*/ + (*out) = new_buffer; + (*outlength) = new_length; + chunk_start = &(*out)[new_length - total_chunk_length]; + + for(i = 0; i < total_chunk_length; i++) chunk_start[i] = chunk[i]; + + return 0; +} + +unsigned lodepng_chunk_create(unsigned char** out, size_t* outlength, unsigned length, + const char* type, const unsigned char* data) +{ + unsigned i; + unsigned char *chunk, *new_buffer; + size_t new_length = (*outlength) + length + 12; + if(new_length < length + 12 || new_length < (*outlength)) return 77; /*integer overflow happened*/ + new_buffer = (unsigned char*)myrealloc(*out, new_length); + if(!new_buffer) return 83; /*alloc fail*/ + (*out) = new_buffer; + (*outlength) = new_length; + chunk = &(*out)[(*outlength) - length - 12]; + + /*1: length*/ + lodepng_set32bitInt(chunk, (unsigned)length); + + /*2: chunk name (4 letters)*/ + chunk[4] = type[0]; + chunk[5] = type[1]; + chunk[6] = type[2]; + chunk[7] = type[3]; + + /*3: the data*/ + for(i = 0; i < length; i++) chunk[8 + i] = data[i]; + + /*4: CRC (of the chunkname characters and the data)*/ + lodepng_chunk_generate_crc(chunk); + + return 0; +} + +/* ////////////////////////////////////////////////////////////////////////// */ +/* / Color types and such / */ +/* ////////////////////////////////////////////////////////////////////////// */ + +/*return type is a LodePNG error code*/ +static unsigned checkColorValidity(LodePNGColorType colortype, unsigned bd) /*bd = bitdepth*/ +{ + switch(colortype) + { + case 0: if(!(bd == 1 || bd == 2 || bd == 4 || bd == 8 || bd == 16)) return 37; break; /*grey*/ + case 2: if(!( bd == 8 || bd == 16)) return 37; break; /*RGB*/ + case 3: if(!(bd == 1 || bd == 2 || bd == 4 || bd == 8 )) return 37; break; /*palette*/ + case 4: if(!( bd == 8 || bd == 16)) return 37; break; /*grey + alpha*/ + case 6: if(!( bd == 8 || bd == 16)) return 37; break; /*RGBA*/ + default: return 31; + } + return 0; /*allowed color type / bits combination*/ +} + +static unsigned getNumColorChannels(LodePNGColorType colortype) +{ + switch(colortype) + { + case 0: return 1; /*grey*/ + case 2: return 3; /*RGB*/ + case 3: return 1; /*palette*/ + case 4: return 2; /*grey + alpha*/ + case 6: return 4; /*RGBA*/ + } + return 0; /*unexisting color type*/ +} + +static unsigned lodepng_get_bpp_lct(LodePNGColorType colortype, unsigned bitdepth) +{ + /*bits per pixel is amount of channels * bits per channel*/ + return getNumColorChannels(colortype) * bitdepth; +} + +/* ////////////////////////////////////////////////////////////////////////// */ + +void lodepng_color_mode_init(LodePNGColorMode* info) +{ + info->key_defined = 0; + info->key_r = info->key_g = info->key_b = 0; + info->colortype = LCT_RGBA; + info->bitdepth = 8; + info->palette = 0; + info->palettesize = 0; +} + +void lodepng_color_mode_cleanup(LodePNGColorMode* info) +{ + lodepng_palette_clear(info); +} + +unsigned lodepng_color_mode_copy(LodePNGColorMode* dest, const LodePNGColorMode* source) +{ + size_t i; + lodepng_color_mode_cleanup(dest); + *dest = *source; + if(source->palette) + { + dest->palette = (unsigned char*)mymalloc(source->palettesize * 4); + if(!dest->palette && source->palettesize) return 83; /*alloc fail*/ + for(i = 0; i < source->palettesize * 4; i++) dest->palette[i] = source->palette[i]; + } + return 0; +} + +static int lodepng_color_mode_equal(const LodePNGColorMode* a, const LodePNGColorMode* b) +{ + size_t i; + if(a->colortype != b->colortype) return 0; + if(a->bitdepth != b->bitdepth) return 0; + if(a->key_defined != b->key_defined) return 0; + if(a->key_defined) + { + if(a->key_r != b->key_r) return 0; + if(a->key_g != b->key_g) return 0; + if(a->key_b != b->key_b) return 0; + } + if(a->palettesize != b->palettesize) return 0; + for(i = 0; i < a->palettesize * 4; i++) + { + if(a->palette[i] != b->palette[i]) return 0; + } + return 1; +} + +void lodepng_palette_clear(LodePNGColorMode* info) +{ + if(info->palette) myfree(info->palette); + info->palettesize = 0; +} + +unsigned lodepng_palette_add(LodePNGColorMode* info, + unsigned char r, unsigned char g, unsigned char b, unsigned char a) +{ + unsigned char* data; + /*the same resize technique as C++ std::vectors is used, and here it's made so that for a palette with + the max of 256 colors, it'll have the exact alloc size*/ + if(!(info->palettesize & (info->palettesize - 1))) /*if palettesize is 0 or a power of two*/ + { + /*allocated data must be at least 4* palettesize (for 4 color bytes)*/ + size_t alloc_size = info->palettesize == 0 ? 4 : info->palettesize * 4 * 2; + data = (unsigned char*)myrealloc(info->palette, alloc_size); + if(!data) return 83; /*alloc fail*/ + else info->palette = data; + } + info->palette[4 * info->palettesize + 0] = r; + info->palette[4 * info->palettesize + 1] = g; + info->palette[4 * info->palettesize + 2] = b; + info->palette[4 * info->palettesize + 3] = a; + info->palettesize++; + return 0; +} + +unsigned lodepng_get_bpp(const LodePNGColorMode* info) +{ + /*calculate bits per pixel out of colortype and bitdepth*/ + return lodepng_get_bpp_lct(info->colortype, info->bitdepth); +} + +unsigned lodepng_get_channels(const LodePNGColorMode* info) +{ + return getNumColorChannels(info->colortype); +} + +unsigned lodepng_is_greyscale_type(const LodePNGColorMode* info) +{ + return info->colortype == LCT_GREY || info->colortype == LCT_GREY_ALPHA; +} + +unsigned lodepng_is_alpha_type(const LodePNGColorMode* info) +{ + return (info->colortype & 4) != 0; /*4 or 6*/ +} + +unsigned lodepng_is_palette_type(const LodePNGColorMode* info) +{ + return info->colortype == LCT_PALETTE; +} + +unsigned lodepng_has_palette_alpha(const LodePNGColorMode* info) +{ + size_t i; + for(i = 0; i < info->palettesize; i++) + { + if(info->palette[i * 4 + 3] < 255) return 1; + } + return 0; +} + +unsigned lodepng_can_have_alpha(const LodePNGColorMode* info) +{ + return info->key_defined + || lodepng_is_alpha_type(info) + || lodepng_has_palette_alpha(info); +} + +size_t lodepng_get_raw_size(unsigned w, unsigned h, const LodePNGColorMode* color) +{ + return (w * h * lodepng_get_bpp(color) + 7) / 8; +} + +size_t lodepng_get_raw_size_lct(unsigned w, unsigned h, LodePNGColorType colortype, unsigned bitdepth) +{ + return (w * h * lodepng_get_bpp_lct(colortype, bitdepth) + 7) / 8; +} + +#ifdef LODEPNG_COMPILE_ANCILLARY_CHUNKS + +static void LodePNGUnknownChunks_init(LodePNGInfo* info) +{ + unsigned i; + for(i = 0; i < 3; i++) info->unknown_chunks_data[i] = 0; + for(i = 0; i < 3; i++) info->unknown_chunks_size[i] = 0; +} + +static void LodePNGUnknownChunks_cleanup(LodePNGInfo* info) +{ + unsigned i; + for(i = 0; i < 3; i++) myfree(info->unknown_chunks_data[i]); +} + +static unsigned LodePNGUnknownChunks_copy(LodePNGInfo* dest, const LodePNGInfo* src) +{ + unsigned i; + + LodePNGUnknownChunks_cleanup(dest); + + for(i = 0; i < 3; i++) + { + size_t j; + dest->unknown_chunks_size[i] = src->unknown_chunks_size[i]; + dest->unknown_chunks_data[i] = (unsigned char*)mymalloc(src->unknown_chunks_size[i]); + if(!dest->unknown_chunks_data[i] && dest->unknown_chunks_size[i]) return 83; /*alloc fail*/ + for(j = 0; j < src->unknown_chunks_size[i]; j++) + { + dest->unknown_chunks_data[i][j] = src->unknown_chunks_data[i][j]; + } + } + + return 0; +} + +/******************************************************************************/ + +static void LodePNGText_init(LodePNGInfo* info) +{ + info->text_num = 0; + info->text_keys = NULL; + info->text_strings = NULL; +} + +static void LodePNGText_cleanup(LodePNGInfo* info) +{ + size_t i; + for(i = 0; i < info->text_num; i++) + { + string_cleanup(&info->text_keys[i]); + string_cleanup(&info->text_strings[i]); + } + myfree(info->text_keys); + myfree(info->text_strings); +} + +static unsigned LodePNGText_copy(LodePNGInfo* dest, const LodePNGInfo* source) +{ + size_t i = 0; + dest->text_keys = 0; + dest->text_strings = 0; + dest->text_num = 0; + for(i = 0; i < source->text_num; i++) + { + CERROR_TRY_RETURN(lodepng_add_text(dest, source->text_keys[i], source->text_strings[i])); + } + return 0; +} + +void lodepng_clear_text(LodePNGInfo* info) +{ + LodePNGText_cleanup(info); +} + +unsigned lodepng_add_text(LodePNGInfo* info, const char* key, const char* str) +{ + char** new_keys = (char**)(myrealloc(info->text_keys, sizeof(char*) * (info->text_num + 1))); + char** new_strings = (char**)(myrealloc(info->text_strings, sizeof(char*) * (info->text_num + 1))); + if(!new_keys || !new_strings) + { + myfree(new_keys); + myfree(new_strings); + return 83; /*alloc fail*/ + } + + info->text_num++; + info->text_keys = new_keys; + info->text_strings = new_strings; + + string_init(&info->text_keys[info->text_num - 1]); + string_set(&info->text_keys[info->text_num - 1], key); + + string_init(&info->text_strings[info->text_num - 1]); + string_set(&info->text_strings[info->text_num - 1], str); + + return 0; +} + +/******************************************************************************/ + +static void LodePNGIText_init(LodePNGInfo* info) +{ + info->itext_num = 0; + info->itext_keys = NULL; + info->itext_langtags = NULL; + info->itext_transkeys = NULL; + info->itext_strings = NULL; +} + +static void LodePNGIText_cleanup(LodePNGInfo* info) +{ + size_t i; + for(i = 0; i < info->itext_num; i++) + { + string_cleanup(&info->itext_keys[i]); + string_cleanup(&info->itext_langtags[i]); + string_cleanup(&info->itext_transkeys[i]); + string_cleanup(&info->itext_strings[i]); + } + myfree(info->itext_keys); + myfree(info->itext_langtags); + myfree(info->itext_transkeys); + myfree(info->itext_strings); +} + +static unsigned LodePNGIText_copy(LodePNGInfo* dest, const LodePNGInfo* source) +{ + size_t i = 0; + dest->itext_keys = 0; + dest->itext_langtags = 0; + dest->itext_transkeys = 0; + dest->itext_strings = 0; + dest->itext_num = 0; + for(i = 0; i < source->itext_num; i++) + { + CERROR_TRY_RETURN(lodepng_add_itext(dest, source->itext_keys[i], source->itext_langtags[i], + source->itext_transkeys[i], source->itext_strings[i])); + } + return 0; +} + +void lodepng_clear_itext(LodePNGInfo* info) +{ + LodePNGIText_cleanup(info); +} + +unsigned lodepng_add_itext(LodePNGInfo* info, const char* key, const char* langtag, + const char* transkey, const char* str) +{ + char** new_keys = (char**)(myrealloc(info->itext_keys, sizeof(char*) * (info->itext_num + 1))); + char** new_langtags = (char**)(myrealloc(info->itext_langtags, sizeof(char*) * (info->itext_num + 1))); + char** new_transkeys = (char**)(myrealloc(info->itext_transkeys, sizeof(char*) * (info->itext_num + 1))); + char** new_strings = (char**)(myrealloc(info->itext_strings, sizeof(char*) * (info->itext_num + 1))); + if(!new_keys || !new_langtags || !new_transkeys || !new_strings) + { + myfree(new_keys); + myfree(new_langtags); + myfree(new_transkeys); + myfree(new_strings); + return 83; /*alloc fail*/ + } + + info->itext_num++; + info->itext_keys = new_keys; + info->itext_langtags = new_langtags; + info->itext_transkeys = new_transkeys; + info->itext_strings = new_strings; + + string_init(&info->itext_keys[info->itext_num - 1]); + string_set(&info->itext_keys[info->itext_num - 1], key); + + string_init(&info->itext_langtags[info->itext_num - 1]); + string_set(&info->itext_langtags[info->itext_num - 1], langtag); + + string_init(&info->itext_transkeys[info->itext_num - 1]); + string_set(&info->itext_transkeys[info->itext_num - 1], transkey); + + string_init(&info->itext_strings[info->itext_num - 1]); + string_set(&info->itext_strings[info->itext_num - 1], str); + + return 0; +} +#endif /*LODEPNG_COMPILE_ANCILLARY_CHUNKS*/ + +void lodepng_info_init(LodePNGInfo* info) +{ + lodepng_color_mode_init(&info->color); + info->interlace_method = 0; + info->compression_method = 0; + info->filter_method = 0; +#ifdef LODEPNG_COMPILE_ANCILLARY_CHUNKS + info->background_defined = 0; + info->background_r = info->background_g = info->background_b = 0; + + LodePNGText_init(info); + LodePNGIText_init(info); + + info->time_defined = 0; + info->phys_defined = 0; + + LodePNGUnknownChunks_init(info); +#endif /*LODEPNG_COMPILE_ANCILLARY_CHUNKS*/ +} + +void lodepng_info_cleanup(LodePNGInfo* info) +{ + lodepng_color_mode_cleanup(&info->color); +#ifdef LODEPNG_COMPILE_ANCILLARY_CHUNKS + LodePNGText_cleanup(info); + LodePNGIText_cleanup(info); + + LodePNGUnknownChunks_cleanup(info); +#endif /*LODEPNG_COMPILE_ANCILLARY_CHUNKS*/ +} + +unsigned lodepng_info_copy(LodePNGInfo* dest, const LodePNGInfo* source) +{ + lodepng_info_cleanup(dest); + *dest = *source; + lodepng_color_mode_init(&dest->color); + CERROR_TRY_RETURN(lodepng_color_mode_copy(&dest->color, &source->color)); + +#ifdef LODEPNG_COMPILE_ANCILLARY_CHUNKS + CERROR_TRY_RETURN(LodePNGText_copy(dest, source)); + CERROR_TRY_RETURN(LodePNGIText_copy(dest, source)); + + LodePNGUnknownChunks_init(dest); + CERROR_TRY_RETURN(LodePNGUnknownChunks_copy(dest, source)); +#endif /*LODEPNG_COMPILE_ANCILLARY_CHUNKS*/ + return 0; +} + +void lodepng_info_swap(LodePNGInfo* a, LodePNGInfo* b) +{ + LodePNGInfo temp = *a; + *a = *b; + *b = temp; +} + +/* ////////////////////////////////////////////////////////////////////////// */ + +/*index: bitgroup index, bits: bitgroup size(1, 2 or 4, in: bitgroup value, out: octet array to add bits to*/ +static void addColorBits(unsigned char* out, size_t index, unsigned bits, unsigned in) +{ + /*p = the partial index in the byte, e.g. with 4 palettebits it is 0 for first half or 1 for second half*/ + unsigned p = index % (8 / bits); + in &= (1 << bits) - 1; /*filter out any other bits of the input value*/ + in = in << (bits * (8 / bits - p - 1)); + if(p == 0) out[index * bits / 8] = in; + else out[index * bits / 8] |= in; +} + +typedef struct ColorTree ColorTree; + +/* +One node of a color tree +This is the data structure used to count the number of unique colors and to get a palette +index for a color. It's a bit like an octree for RGB bits, except that a node has 256 +children and there is one level of the tree per color channel. This may use more memory +than an octree, but this is only used to count up to 256 so it's good enough. +*/ +struct ColorTree +{ + ColorTree* next; /*null, or array of 256 pointers to ColorTree of next level*/ + int index; /*the payload. Only has a meaningful value if this is in the 4th level*/ +}; + +static void color_tree_make_next(ColorTree* tree); + +/*next: whether to create the next array or not*/ +static void color_tree_init(ColorTree* tree, int next) +{ + if(next) color_tree_make_next(tree); + else tree->next = 0; + tree->index = -1; +} + +static void color_tree_make_next(ColorTree* tree) +{ + int i; + tree->next = (ColorTree*)mymalloc(256 * sizeof(ColorTree)); + for(i = 0; i < 256; i++) color_tree_init(&tree->next[i], 0); +} + +static void color_tree_cleanup(ColorTree* tree) +{ + if(tree->next) + { + int i; + for(i = 0; i < 256; i++) color_tree_cleanup(&tree->next[i]); + myfree(tree->next); + } +} + +/*returns -1 if color not present, its index otherwise*/ +static int color_tree_get(ColorTree* tree, unsigned char r, unsigned char g, unsigned char b, unsigned char a) +{ + tree = &tree->next[r]; + if(tree->next == 0) return -1; + tree = &tree->next[g]; + if(tree->next == 0) return -1; + tree = &tree->next[b]; + if(tree->next == 0) return -1; + tree = &tree->next[a]; + + return tree->index; +} + +#ifdef LODEPNG_COMPILE_ENCODER +static int color_tree_has(ColorTree* tree, unsigned char r, unsigned char g, unsigned char b, unsigned char a) +{ + return color_tree_get(tree, r, g, b, a) >= 0; +} +#endif /*LODEPNG_COMPILE_ENCODER*/ + +/*color is not allowed to already exist. Index should be >= 0 (it's signed to be compatible with using -1 for "doesn't exist")*/ +static void color_tree_add(ColorTree* tree, unsigned char r, unsigned char g, unsigned char b, unsigned char a, int index) +{ + tree = &tree->next[r]; + if(tree->next == 0) color_tree_make_next(tree); + tree = &tree->next[g]; + if(tree->next == 0) color_tree_make_next(tree); + tree = &tree->next[b]; + if(tree->next == 0) color_tree_make_next(tree); + tree = &tree->next[a]; + + tree->index = index; +} + +/*put a pixel, given its RGBA color, into image of any color type*/ +static unsigned rgba8ToPixel(unsigned char* out, size_t i, + const LodePNGColorMode* mode, ColorTree* tree /*for palette*/, + unsigned char r, unsigned char g, unsigned char b, unsigned char a) +{ + if(mode->colortype == LCT_GREY) + { + unsigned char grey = r; /*((unsigned short)r + g + b) / 3*/; + if(mode->bitdepth == 8) out[i] = grey; + else if(mode->bitdepth == 16) out[i * 2 + 0] = out[i * 2 + 1] = grey; + else + { + /*take the most significant bits of grey*/ + grey = (grey >> (8 - mode->bitdepth)) & ((1 << mode->bitdepth) - 1); + addColorBits(out, i, mode->bitdepth, grey); + } + } + else if(mode->colortype == LCT_RGB) + { + if(mode->bitdepth == 8) + { + out[i * 3 + 0] = r; + out[i * 3 + 1] = g; + out[i * 3 + 2] = b; + } + else + { + out[i * 6 + 0] = out[i * 6 + 1] = r; + out[i * 6 + 2] = out[i * 6 + 3] = g; + out[i * 6 + 4] = out[i * 6 + 5] = b; + } + } + else if(mode->colortype == LCT_PALETTE) + { + int index = color_tree_get(tree, r, g, b, a); + if(index < 0) return 82; /*color not in palette*/ + if(mode->bitdepth == 8) out[i] = index; + else addColorBits(out, i, mode->bitdepth, index); + } + else if(mode->colortype == LCT_GREY_ALPHA) + { + unsigned char grey = r; /*((unsigned short)r + g + b) / 3*/; + if(mode->bitdepth == 8) + { + out[i * 2 + 0] = grey; + out[i * 2 + 1] = a; + } + else if(mode->bitdepth == 16) + { + out[i * 4 + 0] = out[i * 4 + 1] = grey; + out[i * 4 + 2] = out[i * 4 + 3] = a; + } + } + else if(mode->colortype == LCT_RGBA) + { + if(mode->bitdepth == 8) + { + out[i * 4 + 0] = r; + out[i * 4 + 1] = g; + out[i * 4 + 2] = b; + out[i * 4 + 3] = a; + } + else + { + out[i * 8 + 0] = out[i * 8 + 1] = r; + out[i * 8 + 2] = out[i * 8 + 3] = g; + out[i * 8 + 4] = out[i * 8 + 5] = b; + out[i * 8 + 6] = out[i * 8 + 7] = a; + } + } + + return 0; /*no error*/ +} + +/*put a pixel, given its RGBA16 color, into image of any color 16-bitdepth type*/ +static unsigned rgba16ToPixel(unsigned char* out, size_t i, + const LodePNGColorMode* mode, + unsigned short r, unsigned short g, unsigned short b, unsigned short a) +{ + if(mode->bitdepth != 16) return 85; /*must be 16 for this function*/ + if(mode->colortype == LCT_GREY) + { + unsigned short grey = r; /*((unsigned)r + g + b) / 3*/; + out[i * 2 + 0] = (grey >> 8) & 255; + out[i * 2 + 1] = grey & 255; + } + else if(mode->colortype == LCT_RGB) + { + out[i * 6 + 0] = (r >> 8) & 255; + out[i * 6 + 1] = r & 255; + out[i * 6 + 2] = (g >> 8) & 255; + out[i * 6 + 3] = g & 255; + out[i * 6 + 4] = (b >> 8) & 255; + out[i * 6 + 5] = b & 255; + } + else if(mode->colortype == LCT_GREY_ALPHA) + { + unsigned short grey = r; /*((unsigned)r + g + b) / 3*/; + out[i * 4 + 0] = (grey >> 8) & 255; + out[i * 4 + 1] = grey & 255; + out[i * 4 + 2] = (a >> 8) & 255; + out[i * 4 + 3] = a & 255; + } + else if(mode->colortype == LCT_RGBA) + { + out[i * 8 + 0] = (r >> 8) & 255; + out[i * 8 + 1] = r & 255; + out[i * 8 + 2] = (g >> 8) & 255; + out[i * 8 + 3] = g & 255; + out[i * 8 + 4] = (b >> 8) & 255; + out[i * 8 + 5] = b & 255; + out[i * 8 + 6] = (a >> 8) & 255; + out[i * 8 + 7] = a & 255; + } + + return 0; /*no error*/ +} + +/*Get RGBA8 color of pixel with index i (y * width + x) from the raw image with given color type.*/ +static unsigned getPixelColorRGBA8(unsigned char* r, unsigned char* g, unsigned char* b, unsigned char* a, + const unsigned char* in, size_t i, const LodePNGColorMode* mode) +{ + if(mode->colortype == LCT_GREY) + { + if(mode->bitdepth == 8) + { + *r = *g = *b = in[i]; + if(mode->key_defined && *r == mode->key_r) *a = 0; + else *a = 255; + } + else if(mode->bitdepth == 16) + { + *r = *g = *b = in[i * 2 + 0]; + if(mode->key_defined && 256U * in[i * 2 + 0] + in[i * 2 + 1] == mode->key_r) *a = 0; + else *a = 255; + } + else + { + unsigned highest = ((1U << mode->bitdepth) - 1U); /*highest possible value for this bit depth*/ + size_t j = i * mode->bitdepth; + unsigned value = readBitsFromReversedStream(&j, in, mode->bitdepth); + *r = *g = *b = (value * 255) / highest; + if(mode->key_defined && value == mode->key_r) *a = 0; + else *a = 255; + } + } + else if(mode->colortype == LCT_RGB) + { + if(mode->bitdepth == 8) + { + *r = in[i * 3 + 0]; *g = in[i * 3 + 1]; *b = in[i * 3 + 2]; + if(mode->key_defined && *r == mode->key_r && *g == mode->key_g && *b == mode->key_b) *a = 0; + else *a = 255; + } + else + { + *r = in[i * 6 + 0]; + *g = in[i * 6 + 2]; + *b = in[i * 6 + 4]; + if(mode->key_defined && 256U * in[i * 6 + 0] + in[i * 6 + 1] == mode->key_r + && 256U * in[i * 6 + 2] + in[i * 6 + 3] == mode->key_g + && 256U * in[i * 6 + 4] + in[i * 6 + 5] == mode->key_b) *a = 0; + else *a = 255; + } + } + else if(mode->colortype == LCT_PALETTE) + { + unsigned index; + if(mode->bitdepth == 8) index = in[i]; + else + { + size_t j = i * mode->bitdepth; + index = readBitsFromReversedStream(&j, in, mode->bitdepth); + } + if(index >= mode->palettesize) return 47; /*index out of palette*/ + *r = mode->palette[index * 4 + 0]; + *g = mode->palette[index * 4 + 1]; + *b = mode->palette[index * 4 + 2]; + *a = mode->palette[index * 4 + 3]; + } + else if(mode->colortype == LCT_GREY_ALPHA) + { + if(mode->bitdepth == 8) + { + *r = *g = *b = in[i * 2 + 0]; + *a = in[i * 2 + 1]; + } + else + { + *r = *g = *b = in[i * 4 + 0]; + *a = in[i * 4 + 2]; + } + } + else if(mode->colortype == LCT_RGBA) + { + if(mode->bitdepth == 8) + { + *r = in[i * 4 + 0]; *g = in[i * 4 + 1]; *b = in[i * 4 + 2]; *a = in[i * 4 + 3]; + } + else + { + *r = in[i * 8 + 0]; *g = in[i * 8 + 2]; *b = in[i * 8 + 4]; *a = in[i * 8 + 6]; + } + } + + return 0; /*no error*/ +} + +/*Get RGBA16 color of pixel with index i (y * width + x) from the raw image with +given color type, but the given color type must be 16-bit itself.*/ +static unsigned getPixelColorRGBA16(unsigned short* r, unsigned short* g, unsigned short* b, unsigned short* a, + const unsigned char* in, size_t i, const LodePNGColorMode* mode) +{ + if(mode->bitdepth != 16) return 85; /*error: this function only supports 16-bit input*/ + + if(mode->colortype == LCT_GREY) + { + *r = *g = *b = 256 * in[i * 2 + 0] + in[i * 2 + 1]; + if(mode->key_defined && 256U * in[i * 2 + 0] + in[i * 2 + 1] == mode->key_r) *a = 0; + else *a = 65535; + } + else if(mode->colortype == LCT_RGB) + { + *r = 256 * in[i * 6 + 0] + in[i * 6 + 1]; + *g = 256 * in[i * 6 + 2] + in[i * 6 + 3]; + *b = 256 * in[i * 6 + 4] + in[i * 6 + 5]; + if(mode->key_defined && 256U * in[i * 6 + 0] + in[i * 6 + 1] == mode->key_r + && 256U * in[i * 6 + 2] + in[i * 6 + 3] == mode->key_g + && 256U * in[i * 6 + 4] + in[i * 6 + 5] == mode->key_b) *a = 0; + else *a = 65535; + } + else if(mode->colortype == LCT_GREY_ALPHA) + { + *r = *g = *b = 256 * in[i * 4 + 0] + in[i * 4 + 1]; + *a = 256 * in[i * 4 + 2] + in[i * 4 + 3]; + } + else if(mode->colortype == LCT_RGBA) + { + *r = 256 * in[i * 8 + 0] + in[i * 8 + 1]; + *g = 256 * in[i * 8 + 2] + in[i * 8 + 3]; + *b = 256 * in[i * 8 + 4] + in[i * 8 + 5]; + *a = 256 * in[i * 8 + 6] + in[i * 8 + 7]; + } + else return 85; /*error: this function only supports 16-bit input*/ + + return 0; /*no error*/ +} + +/* +converts from any color type to 24-bit or 32-bit (later maybe more supported). return value = LodePNG error code +the out buffer must have (w * h * bpp + 7) / 8 bytes, where bpp is the bits per pixel of the output color type +(lodepng_get_bpp) for < 8 bpp images, there may _not_ be padding bits at the end of scanlines. +*/ +unsigned lodepng_convert(unsigned char* out, const unsigned char* in, + LodePNGColorMode* mode_out, LodePNGColorMode* mode_in, + unsigned w, unsigned h) +{ + unsigned error = 0; + size_t i; + ColorTree tree; + + if(lodepng_color_mode_equal(mode_out, mode_in)) + { + size_t numbytes = lodepng_get_raw_size(w, h, mode_in); + for(i = 0; i < numbytes; i++) out[i] = in[i]; + return error; + } + + if(mode_out->colortype == LCT_PALETTE) + { + size_t palsize = 1 << mode_out->bitdepth; + if(mode_out->palettesize < palsize) palsize = mode_out->palettesize; + color_tree_init(&tree, 1); + for(i = 0; i < palsize; i++) + { + unsigned char* p = &mode_out->palette[i * 4]; + color_tree_add(&tree, p[0], p[1], p[2], p[3], i); + } + } + + if(mode_in->bitdepth == 16 && mode_out->bitdepth == 16) + { + size_t numpixels = w * h; + for(i = 0; i < numpixels; i++) + { + unsigned short r = 0, g = 0, b = 0, a = 0; + error = getPixelColorRGBA16(&r, &g, &b, &a, in, i, mode_in); + if(error) return error; + error = rgba16ToPixel(out, i, mode_out, r, g, b, a); + if(error) return error; + } + } + else + { + size_t numpixels = w * h; + for(i = 0; i < numpixels; i++) + { + unsigned char r = 0, g = 0, b = 0, a = 0; + error = getPixelColorRGBA8(&r, &g, &b, &a, in, i, mode_in); + if(error) return error; + error = rgba8ToPixel(out, i, mode_out, &tree, r, g, b, a); + if(error) return error; + } + } + + if(mode_out->colortype == LCT_PALETTE) + { + color_tree_cleanup(&tree); + } + + return error; +} + +#ifdef LODEPNG_COMPILE_ENCODER + +typedef struct ColorProfile +{ + unsigned char sixteenbit; /*needs more than 8 bits per channel*/ + unsigned char sixteenbit_done; + + + unsigned char colored; /*not greyscale*/ + unsigned char colored_done; + + unsigned char key; /*a color key is required, or more*/ + unsigned short key_r; /*these values are always in 16-bit bitdepth in the profile*/ + unsigned short key_g; + unsigned short key_b; + unsigned char alpha; /*alpha channel, or alpha palette, required*/ + unsigned char alpha_done; + + unsigned numcolors; + ColorTree tree; /*for listing the counted colors, up to 256*/ + unsigned char* palette; /*size 1024. Remember up to the first 256 RGBA colors*/ + unsigned maxnumcolors; /*if more than that amount counted*/ + unsigned char numcolors_done; + + unsigned greybits; /*amount of bits required for greyscale (1, 2, 4, 8). Does not take 16 bit into account.*/ + unsigned char greybits_done; + +} ColorProfile; + +static void color_profile_init(ColorProfile* profile, LodePNGColorMode* mode) +{ + profile->sixteenbit = 0; + profile->sixteenbit_done = mode->bitdepth == 16 ? 0 : 1; + + profile->colored = 0; + profile->colored_done = lodepng_is_greyscale_type(mode) ? 1 : 0; + + profile->key = 0; + profile->alpha = 0; + profile->alpha_done = lodepng_can_have_alpha(mode) ? 0 : 1; + + profile->numcolors = 0; + color_tree_init(&profile->tree, 1); + profile->palette = (unsigned char*)mymalloc(1024); + profile->maxnumcolors = 257; + if(lodepng_get_bpp(mode) <= 8) + { + int bpp = lodepng_get_bpp(mode); + profile->maxnumcolors = bpp == 1 ? 2 : (bpp == 2 ? 4 : (bpp == 4 ? 16 : 256)); + } + profile->numcolors_done = 0; + + profile->greybits = 1; + profile->greybits_done = lodepng_get_bpp(mode) == 1 ? 1 : 0; +} + +static void color_profile_cleanup(ColorProfile* profile) +{ + color_tree_cleanup(&profile->tree); + myfree(profile->palette); +} + +/*function used for debug purposes with C++*/ +/*void printColorProfile(ColorProfile* p) +{ + std::cout << "sixteenbit: " << (int)p->sixteenbit << std::endl; + std::cout << "sixteenbit_done: " << (int)p->sixteenbit_done << std::endl; + std::cout << "colored: " << (int)p->colored << std::endl; + std::cout << "colored_done: " << (int)p->colored_done << std::endl; + std::cout << "key: " << (int)p->key << std::endl; + std::cout << "key_r: " << (int)p->key_r << std::endl; + std::cout << "key_g: " << (int)p->key_g << std::endl; + std::cout << "key_b: " << (int)p->key_b << std::endl; + std::cout << "alpha: " << (int)p->alpha << std::endl; + std::cout << "alpha_done: " << (int)p->alpha_done << std::endl; + std::cout << "numcolors: " << (int)p->numcolors << std::endl; + std::cout << "maxnumcolors: " << (int)p->maxnumcolors << std::endl; + std::cout << "numcolors_done: " << (int)p->numcolors_done << std::endl; + std::cout << "greybits: " << (int)p->greybits << std::endl; + std::cout << "greybits_done: " << (int)p->greybits_done << std::endl; +}*/ + +/*Returns how many bits needed to represent given value (max 8 bit)*/ +unsigned getValueRequiredBits(unsigned char value) +{ + if(value == 0 || value == 255) return 1; + /*The scaling of 2-bit and 4-bit values uses multiples of 85 and 17*/ + if(value % 17 == 0) return value % 85 == 0 ? 2 : 4; + return 8; +} + +/*profile must already have been inited with mode. +It's ok to set some parameters of profile to done already.*/ +static unsigned get_color_profile(ColorProfile* profile, + const unsigned char* in, size_t numpixels, + LodePNGColorMode* mode) +{ + unsigned error = 0; + size_t i; + + if(mode->bitdepth == 16) + { + for(i = 0; i < numpixels; i++) + { + unsigned short r, g, b, a; + error = getPixelColorRGBA16(&r, &g, &b, &a, in, i, mode); + if(error) break; + + /*a color is considered good for 8-bit if the first byte and the second byte are equal, + (so if it's divisible through 257), NOT necessarily if the second byte is 0*/ + if(!profile->sixteenbit_done + && (((r & 255) != ((r >> 8) & 255)) + || ((g & 255) != ((g >> 8) & 255)) + || ((b & 255) != ((b >> 8) & 255)))) + { + profile->sixteenbit = 1; + profile->sixteenbit_done = 1; + profile->greybits_done = 1; /*greybits is not applicable anymore at 16-bit*/ + profile->numcolors_done = 1; /*counting colors no longer useful, palette doesn't support 16-bit*/ + } + + if(!profile->colored_done && (r != g || r != b)) + { + profile->colored = 1; + profile->colored_done = 1; + profile->greybits_done = 1; /*greybits is not applicable anymore*/ + } + + if(!profile->alpha_done && a != 255) + { + if(a == 0 && !(profile->key && (r != profile->key_r || g != profile->key_g || b != profile->key_b))) + { + if(!profile->key) + { + profile->key = 1; + profile->key_r = r; + profile->key_g = g; + profile->key_b = b; + } + } + else + { + profile->alpha = 1; + profile->alpha_done = 1; + profile->greybits_done = 1; /*greybits is not applicable anymore*/ + } + } + + if(!profile->greybits_done) + { + /*assuming 8-bit r, this test does not care about 16-bit*/ + unsigned bits = getValueRequiredBits(r); + if(bits > profile->greybits) profile->greybits = bits; + if(profile->greybits >= 8) profile->greybits_done = 1; + } + + if(!profile->numcolors_done) + { + /*assuming 8-bit rgba, this test does not care about 16-bit*/ + if(!color_tree_has(&profile->tree, r, g, b, a)) + { + color_tree_add(&profile->tree, r, g, b, a, profile->numcolors); + if(profile->numcolors < 256) + { + unsigned char* p = profile->palette; + unsigned i = profile->numcolors; + p[i * 4 + 0] = r; + p[i * 4 + 1] = g; + p[i * 4 + 2] = b; + p[i * 4 + 3] = a; + } + profile->numcolors++; + if(profile->numcolors >= profile->maxnumcolors) profile->numcolors_done = 1; + } + } + + if(profile->alpha_done && profile->numcolors_done + && profile->colored_done && profile->sixteenbit_done && profile->greybits_done) + { + break; + } + }; + } + else + { + for(i = 0; i < numpixels; i++) + { + unsigned char r, g, b, a; + error = getPixelColorRGBA8(&r, &g, &b, &a, in, i, mode); + if(error) break; + + if(!profile->colored_done && (r != g || r != b)) + { + profile->colored = 1; + profile->colored_done = 1; + profile->greybits_done = 1; /*greybits is not applicable anymore*/ + } + + if(!profile->alpha_done && a != 255) + { + if(a == 0 && !(profile->key && (r != profile->key_r || g != profile->key_g || b != profile->key_b))) + { + if(!profile->key) + { + profile->key = 1; + profile->key_r = r; + profile->key_g = g; + profile->key_b = b; + } + } + else + { + profile->alpha = 1; + profile->alpha_done = 1; + profile->greybits_done = 1; /*greybits is not applicable anymore*/ + } + } + + if(!profile->greybits_done) + { + unsigned bits = getValueRequiredBits(r); + if(bits > profile->greybits) profile->greybits = bits; + if(profile->greybits >= 8) profile->greybits_done = 1; + } + + if(!profile->numcolors_done) + { + if(!color_tree_has(&profile->tree, r, g, b, a)) + { + + color_tree_add(&profile->tree, r, g, b, a, profile->numcolors); + if(profile->numcolors < 256) + { + unsigned char* p = profile->palette; + unsigned i = profile->numcolors; + p[i * 4 + 0] = r; + p[i * 4 + 1] = g; + p[i * 4 + 2] = b; + p[i * 4 + 3] = a; + } + profile->numcolors++; + if(profile->numcolors >= profile->maxnumcolors) profile->numcolors_done = 1; + } + } + + if(profile->alpha_done && profile->numcolors_done && profile->colored_done && profile->greybits_done) + { + break; + } + }; + } + + /*make the profile's key always 16-bit for consistency*/ + if(mode->bitdepth < 16) + { + /*repeat each byte twice*/ + profile->key_r *= 257; + profile->key_g *= 257; + profile->key_b *= 257; + } + + return error; +} + +/*updates values of mode with a potentially smaller color model. mode_out should +contain the user chosen color model, but will be overwritten with the new chosen one.*/ +static unsigned doAutoChooseColor(LodePNGColorMode* mode_out, + const unsigned char* image, unsigned w, unsigned h, LodePNGColorMode* mode_in, + LodePNGAutoConvert auto_convert) +{ + ColorProfile profile; + unsigned error = 0; + + if(auto_convert == LAC_ALPHA) + { + if(mode_out->colortype != LCT_RGBA && mode_out->colortype != LCT_GREY_ALPHA) return 0; + } + + color_profile_init(&profile, mode_in); + if(auto_convert == LAC_ALPHA) + { + profile.colored_done = 1; + profile.greybits_done = 1; + profile.numcolors_done = 1; + profile.sixteenbit_done = 1; + } + error = get_color_profile(&profile, image, w * h, mode_in); + + if(!error && auto_convert == LAC_ALPHA) + { + if(!profile.alpha) + { + mode_out->colortype = (mode_out->colortype == LCT_RGBA ? LCT_RGB : LCT_GREY); + } + } + else if(!error && auto_convert != LAC_ALPHA) + { + mode_out->key_defined = 0; + + if(profile.sixteenbit) + { + mode_out->bitdepth = 16; + if(profile.alpha) + { + mode_out->colortype = profile.colored ? LCT_RGBA : LCT_GREY_ALPHA; + } + else + { + mode_out->colortype = profile.colored ? LCT_RGB : LCT_GREY; + if(profile.key) + { + mode_out->key_defined = 1; + mode_out->key_r = profile.key_r; + mode_out->key_g = profile.key_g; + mode_out->key_b = profile.key_b; + } + } + } + else /*less than 16 bits per channel*/ + { + /*don't add palette overhead if image hasn't got a lot of pixels*/ + unsigned n = profile.numcolors; + int palette_ok = n <= 256 && (n * 2 < w * h); + unsigned palettebits = n <= 2 ? 1 : (n <= 4 ? 2 : (n <= 16 ? 4 : 8)); + int grey_ok = !profile.colored && !profile.alpha; /*grey without alpha, with potentially low bits*/ + if(palette_ok || grey_ok) + { + if(!palette_ok || (grey_ok && profile.greybits <= palettebits)) + { + mode_out->colortype = LCT_GREY; + mode_out->bitdepth = profile.greybits; + if(profile.key) + { + unsigned keyval = profile.key_r; + keyval &= (profile.greybits - 1); /*same subgroup of bits repeated, so taking right bits is fine*/ + mode_out->key_defined = 1; + mode_out->key_r = keyval; + mode_out->key_g = keyval; + mode_out->key_b = keyval; + } + } + else + { + /*fill in the palette*/ + unsigned i; + unsigned char* p = profile.palette; + for(i = 0; i < profile.numcolors; i++) + { + error = lodepng_palette_add(mode_out, p[i * 4 + 0], p[i * 4 + 1], p[i * 4 + 2], p[i * 4 + 3]); + if(error) break; + } + + mode_out->colortype = LCT_PALETTE; + mode_out->bitdepth = palettebits; + } + } + else /*8-bit per channel*/ + { + mode_out->bitdepth = 8; + if(profile.alpha) + { + mode_out->colortype = profile.colored ? LCT_RGBA : LCT_GREY_ALPHA; + } + else + { + mode_out->colortype = profile.colored ? LCT_RGB : LCT_GREY /*LCT_GREY normally won't occur, already done earlier*/; + if(profile.key) + { + mode_out->key_defined = 1; + mode_out->key_r = profile.key_r % 256; + mode_out->key_g = profile.key_g % 256; + mode_out->key_b = profile.key_b % 256; + } + } + } + } + } + + color_profile_cleanup(&profile); + + if(mode_out->colortype == LCT_PALETTE && mode_in->palettesize == mode_out->palettesize) + { + /*In this case keep the palette order of the input, so that the user can choose an optimal one*/ + size_t i; + for(i = 0; i < mode_in->palettesize * 4; i++) + { + mode_out->palette[i] = mode_in->palette[i]; + } + } + + if(auto_convert == LAC_AUTO_NO_NIBBLES && mode_out->bitdepth < 8) + { + /*palette can keep its small amount of colors, as long as no indices use it*/ + mode_out->bitdepth = 8; + } + + return error; +} + +#endif /* #ifdef LODEPNG_COMPILE_ENCODER */ + +/* +Paeth predicter, used by PNG filter type 4 +The parameters are of type short, but should come from unsigned chars, the shorts +are only needed to make the paeth calculation correct. +*/ +static unsigned char paethPredictor(short a, short b, short c) +{ + short pa = abs(b - c); + short pb = abs(a - c); + short pc = abs(a + b - c - c); + + if(pc < pa && pc < pb) return (unsigned char)c; + else if(pb < pa) return (unsigned char)b; + else return (unsigned char)a; +} + +/*shared values used by multiple Adam7 related functions*/ + +static const unsigned ADAM7_IX[7] = { 0, 4, 0, 2, 0, 1, 0 }; /*x start values*/ +static const unsigned ADAM7_IY[7] = { 0, 0, 4, 0, 2, 0, 1 }; /*y start values*/ +static const unsigned ADAM7_DX[7] = { 8, 8, 4, 4, 2, 2, 1 }; /*x delta values*/ +static const unsigned ADAM7_DY[7] = { 8, 8, 8, 4, 4, 2, 2 }; /*y delta values*/ + +static void Adam7_getpassvalues(unsigned passw[7], unsigned passh[7], size_t filter_passstart[8], + size_t padded_passstart[8], size_t passstart[8], unsigned w, unsigned h, unsigned bpp) +{ + /*the passstart values have 8 values: the 8th one indicates the byte after the end of the 7th (= last) pass*/ + unsigned i; + + /*calculate width and height in pixels of each pass*/ + for(i = 0; i < 7; i++) + { + passw[i] = (w + ADAM7_DX[i] - ADAM7_IX[i] - 1) / ADAM7_DX[i]; + passh[i] = (h + ADAM7_DY[i] - ADAM7_IY[i] - 1) / ADAM7_DY[i]; + if(passw[i] == 0) passh[i] = 0; + if(passh[i] == 0) passw[i] = 0; + } + + filter_passstart[0] = padded_passstart[0] = passstart[0] = 0; + for(i = 0; i < 7; i++) + { + /*if passw[i] is 0, it's 0 bytes, not 1 (no filtertype-byte)*/ + filter_passstart[i + 1] = filter_passstart[i] + + ((passw[i] && passh[i]) ? passh[i] * (1 + (passw[i] * bpp + 7) / 8) : 0); + /*bits padded if needed to fill full byte at end of each scanline*/ + padded_passstart[i + 1] = padded_passstart[i] + passh[i] * ((passw[i] * bpp + 7) / 8); + /*only padded at end of reduced image*/ + passstart[i + 1] = passstart[i] + (passh[i] * passw[i] * bpp + 7) / 8; + } +} + +#ifdef LODEPNG_COMPILE_DECODER + +/* ////////////////////////////////////////////////////////////////////////// */ +/* / PNG Decoder / */ +/* ////////////////////////////////////////////////////////////////////////// */ + +/*read the information from the header and store it in the LodePNGInfo. return value is error*/ +unsigned lodepng_inspect(unsigned* w, unsigned* h, LodePNGState* state, + const unsigned char* in, size_t insize) +{ + LodePNGInfo* info = &state->info_png; + if(insize == 0 || in == 0) + { + CERROR_RETURN_ERROR(state->error, 48); /*error: the given data is empty*/ + } + if(insize < 29) + { + CERROR_RETURN_ERROR(state->error, 27); /*error: the data length is smaller than the length of a PNG header*/ + } + + /*when decoding a new PNG image, make sure all parameters created after previous decoding are reset*/ + lodepng_info_cleanup(info); + lodepng_info_init(info); + + if(in[0] != 137 || in[1] != 80 || in[2] != 78 || in[3] != 71 + || in[4] != 13 || in[5] != 10 || in[6] != 26 || in[7] != 10) + { + CERROR_RETURN_ERROR(state->error, 28); /*error: the first 8 bytes are not the correct PNG signature*/ + } + if(in[12] != 'I' || in[13] != 'H' || in[14] != 'D' || in[15] != 'R') + { + CERROR_RETURN_ERROR(state->error, 29); /*error: it doesn't start with a IHDR chunk!*/ + } + + /*read the values given in the header*/ + *w = lodepng_read32bitInt(&in[16]); + *h = lodepng_read32bitInt(&in[20]); + info->color.bitdepth = in[24]; + info->color.colortype = (LodePNGColorType)in[25]; + info->compression_method = in[26]; + info->filter_method = in[27]; + info->interlace_method = in[28]; + + if(!state->decoder.ignore_crc) + { + unsigned CRC = lodepng_read32bitInt(&in[29]); + unsigned checksum = lodepng_crc32(&in[12], 17); + if(CRC != checksum) + { + CERROR_RETURN_ERROR(state->error, 57); /*invalid CRC*/ + } + } + + /*error: only compression method 0 is allowed in the specification*/ + if(info->compression_method != 0) CERROR_RETURN_ERROR(state->error, 32); + /*error: only filter method 0 is allowed in the specification*/ + if(info->filter_method != 0) CERROR_RETURN_ERROR(state->error, 33); + /*error: only interlace methods 0 and 1 exist in the specification*/ + if(info->interlace_method > 1) CERROR_RETURN_ERROR(state->error, 34); + + state->error = checkColorValidity(info->color.colortype, info->color.bitdepth); + return state->error; +} + +static unsigned unfilterScanline(unsigned char* recon, const unsigned char* scanline, const unsigned char* precon, + size_t bytewidth, unsigned char filterType, size_t length) +{ + /* + For PNG filter method 0 + unfilter a PNG image scanline by scanline. when the pixels are smaller than 1 byte, + the filter works byte per byte (bytewidth = 1) + precon is the previous unfiltered scanline, recon the result, scanline the current one + the incoming scanlines do NOT include the filtertype byte, that one is given in the parameter filterType instead + recon and scanline MAY be the same memory address! precon must be disjoint. + */ + + size_t i; + switch(filterType) + { + case 0: + for(i = 0; i < length; i++) recon[i] = scanline[i]; + break; + case 1: + for(i = 0; i < bytewidth; i++) recon[i] = scanline[i]; + for(i = bytewidth; i < length; i++) recon[i] = scanline[i] + recon[i - bytewidth]; + break; + case 2: + if(precon) + { + for(i = 0; i < length; i++) recon[i] = scanline[i] + precon[i]; + } + else + { + for(i = 0; i < length; i++) recon[i] = scanline[i]; + } + break; + case 3: + if(precon) + { + for(i = 0; i < bytewidth; i++) recon[i] = scanline[i] + precon[i] / 2; + for(i = bytewidth; i < length; i++) recon[i] = scanline[i] + ((recon[i - bytewidth] + precon[i]) / 2); + } + else + { + for(i = 0; i < bytewidth; i++) recon[i] = scanline[i]; + for(i = bytewidth; i < length; i++) recon[i] = scanline[i] + recon[i - bytewidth] / 2; + } + break; + case 4: + if(precon) + { + for(i = 0; i < bytewidth; i++) + { + recon[i] = (scanline[i] + precon[i]); /*paethPredictor(0, precon[i], 0) is always precon[i]*/ + } + for(i = bytewidth; i < length; i++) + { + recon[i] = (scanline[i] + paethPredictor(recon[i - bytewidth], precon[i], precon[i - bytewidth])); + } + } + else + { + for(i = 0; i < bytewidth; i++) + { + recon[i] = scanline[i]; + } + for(i = bytewidth; i < length; i++) + { + /*paethPredictor(recon[i - bytewidth], 0, 0) is always recon[i - bytewidth]*/ + recon[i] = (scanline[i] + recon[i - bytewidth]); + } + } + break; + default: return 36; /*error: unexisting filter type given*/ + } + return 0; +} + +static unsigned unfilter(unsigned char* out, const unsigned char* in, unsigned w, unsigned h, unsigned bpp) +{ + /* + For PNG filter method 0 + this function unfilters a single image (e.g. without interlacing this is called once, with Adam7 seven times) + out must have enough bytes allocated already, in must have the scanlines + 1 filtertype byte per scanline + w and h are image dimensions or dimensions of reduced image, bpp is bits per pixel + in and out are allowed to be the same memory address (but aren't the same size since in has the extra filter bytes) + */ + + unsigned y; + unsigned char* prevline = 0; + + /*bytewidth is used for filtering, is 1 when bpp < 8, number of bytes per pixel otherwise*/ + size_t bytewidth = (bpp + 7) / 8; + size_t linebytes = (w * bpp + 7) / 8; + + for(y = 0; y < h; y++) + { + size_t outindex = linebytes * y; + size_t inindex = (1 + linebytes) * y; /*the extra filterbyte added to each row*/ + unsigned char filterType = in[inindex]; + + CERROR_TRY_RETURN(unfilterScanline(&out[outindex], &in[inindex + 1], prevline, bytewidth, filterType, linebytes)); + + prevline = &out[outindex]; + } + + return 0; +} + +static void Adam7_deinterlace(unsigned char* out, const unsigned char* in, unsigned w, unsigned h, unsigned bpp) +{ + /*Note: this function works on image buffers WITHOUT padding bits at end of scanlines + with non-multiple-of-8 bit amounts, only between reduced images is padding + out must be big enough AND must be 0 everywhere if bpp < 8 in the current implementation + (because that's likely a little bit faster)*/ + unsigned passw[7], passh[7]; + size_t filter_passstart[8], padded_passstart[8], passstart[8]; + unsigned i; + + Adam7_getpassvalues(passw, passh, filter_passstart, padded_passstart, passstart, w, h, bpp); + + if(bpp >= 8) + { + for(i = 0; i < 7; i++) + { + unsigned x, y, b; + size_t bytewidth = bpp / 8; + for(y = 0; y < passh[i]; y++) + for(x = 0; x < passw[i]; x++) + { + size_t pixelinstart = passstart[i] + (y * passw[i] + x) * bytewidth; + size_t pixeloutstart = ((ADAM7_IY[i] + y * ADAM7_DY[i]) * w + ADAM7_IX[i] + x * ADAM7_DX[i]) * bytewidth; + for(b = 0; b < bytewidth; b++) + { + out[pixeloutstart + b] = in[pixelinstart + b]; + } + } + } + } + else /*bpp < 8: Adam7 with pixels < 8 bit is a bit trickier: with bit pointers*/ + { + for(i = 0; i < 7; i++) + { + unsigned x, y, b; + unsigned ilinebits = bpp * passw[i]; + unsigned olinebits = bpp * w; + size_t obp, ibp; /*bit pointers (for out and in buffer)*/ + for(y = 0; y < passh[i]; y++) + for(x = 0; x < passw[i]; x++) + { + ibp = (8 * passstart[i]) + (y * ilinebits + x * bpp); + obp = (ADAM7_IY[i] + y * ADAM7_DY[i]) * olinebits + (ADAM7_IX[i] + x * ADAM7_DX[i]) * bpp; + for(b = 0; b < bpp; b++) + { + unsigned char bit = readBitFromReversedStream(&ibp, in); + /*note that this function assumes the out buffer is completely 0, use setBitOfReversedStream otherwise*/ + setBitOfReversedStream0(&obp, out, bit); + } + } + } + } +} + +static void removePaddingBits(unsigned char* out, const unsigned char* in, + size_t olinebits, size_t ilinebits, unsigned h) +{ + /* + After filtering there are still padding bits if scanlines have non multiple of 8 bit amounts. They need + to be removed (except at last scanline of (Adam7-reduced) image) before working with pure image buffers + for the Adam7 code, the color convert code and the output to the user. + in and out are allowed to be the same buffer, in may also be higher but still overlapping; in must + have >= ilinebits*h bits, out must have >= olinebits*h bits, olinebits must be <= ilinebits + also used to move bits after earlier such operations happened, e.g. in a sequence of reduced images from Adam7 + only useful if (ilinebits - olinebits) is a value in the range 1..7 + */ + unsigned y; + size_t diff = ilinebits - olinebits; + size_t ibp = 0, obp = 0; /*input and output bit pointers*/ + for(y = 0; y < h; y++) + { + size_t x; + for(x = 0; x < olinebits; x++) + { + unsigned char bit = readBitFromReversedStream(&ibp, in); + setBitOfReversedStream(&obp, out, bit); + } + ibp += diff; + } +} + +/*out must be buffer big enough to contain full image, and in must contain the full decompressed data from +the IDAT chunks (with filter index bytes and possible padding bits) +return value is error*/ +static unsigned postProcessScanlines(unsigned char* out, unsigned char* in, + unsigned w, unsigned h, const LodePNGInfo* info_png) +{ + /* + This function converts the filtered-padded-interlaced data into pure 2D image buffer with the PNG's colortype. + Steps: + *) if no Adam7: 1) unfilter 2) remove padding bits (= posible extra bits per scanline if bpp < 8) + *) if adam7: 1) 7x unfilter 2) 7x remove padding bits 3) Adam7_deinterlace + NOTE: the in buffer will be overwritten with intermediate data! + */ + unsigned bpp = lodepng_get_bpp(&info_png->color); + if(bpp == 0) return 31; /*error: invalid colortype*/ + + if(info_png->interlace_method == 0) + { + if(bpp < 8 && w * bpp != ((w * bpp + 7) / 8) * 8) + { + CERROR_TRY_RETURN(unfilter(in, in, w, h, bpp)); + removePaddingBits(out, in, w * bpp, ((w * bpp + 7) / 8) * 8, h); + } + /*we can immediatly filter into the out buffer, no other steps needed*/ + else CERROR_TRY_RETURN(unfilter(out, in, w, h, bpp)); + } + else /*interlace_method is 1 (Adam7)*/ + { + unsigned passw[7], passh[7]; size_t filter_passstart[8], padded_passstart[8], passstart[8]; + unsigned i; + + Adam7_getpassvalues(passw, passh, filter_passstart, padded_passstart, passstart, w, h, bpp); + + for(i = 0; i < 7; i++) + { + CERROR_TRY_RETURN(unfilter(&in[padded_passstart[i]], &in[filter_passstart[i]], passw[i], passh[i], bpp)); + /*TODO: possible efficiency improvement: if in this reduced image the bits fit nicely in 1 scanline, + move bytes instead of bits or move not at all*/ + if(bpp < 8) + { + /*remove padding bits in scanlines; after this there still may be padding + bits between the different reduced images: each reduced image still starts nicely at a byte*/ + removePaddingBits(&in[passstart[i]], &in[padded_passstart[i]], passw[i] * bpp, + ((passw[i] * bpp + 7) / 8) * 8, passh[i]); + } + } + + Adam7_deinterlace(out, in, w, h, bpp); + } + + return 0; +} + +/*read a PNG, the result will be in the same color type as the PNG (hence "generic")*/ +static void decodeGeneric(unsigned char** out, unsigned* w, unsigned* h, + LodePNGState* state, + const unsigned char* in, size_t insize) +{ + unsigned char IEND = 0; + const unsigned char* chunk; + size_t i; + ucvector idat; /*the data from idat chunks*/ + + /*for unknown chunk order*/ + unsigned unknown = 0; +#ifdef LODEPNG_COMPILE_ANCILLARY_CHUNKS + unsigned critical_pos = 1; /*1 = after IHDR, 2 = after PLTE, 3 = after IDAT*/ +#endif /*LODEPNG_COMPILE_ANCILLARY_CHUNKS*/ + + /*provide some proper output values if error will happen*/ + *out = 0; + + state->error = lodepng_inspect(w, h, state, in, insize); /*reads header and resets other parameters in state->info_png*/ + if(state->error) return; + + ucvector_init(&idat); + chunk = &in[33]; /*first byte of the first chunk after the header*/ + + /*loop through the chunks, ignoring unknown chunks and stopping at IEND chunk. + IDAT data is put at the start of the in buffer*/ + while(!IEND && !state->error) + { + unsigned chunkLength; + const unsigned char* data; /*the data in the chunk*/ + + /*error: size of the in buffer too small to contain next chunk*/ + if((size_t)((chunk - in) + 12) > insize || chunk < in) CERROR_BREAK(state->error, 30); + + /*length of the data of the chunk, excluding the length bytes, chunk type and CRC bytes*/ + chunkLength = lodepng_chunk_length(chunk); + /*error: chunk length larger than the max PNG chunk size*/ + if(chunkLength > 2147483647) CERROR_BREAK(state->error, 63); + + if((size_t)((chunk - in) + chunkLength + 12) > insize || (chunk + chunkLength + 12) < in) + { + CERROR_BREAK(state->error, 64); /*error: size of the in buffer too small to contain next chunk*/ + } + + data = lodepng_chunk_data_const(chunk); + + /*IDAT chunk, containing compressed image data*/ + if(lodepng_chunk_type_equals(chunk, "IDAT")) + { + size_t oldsize = idat.size; + if(!ucvector_resize(&idat, oldsize + chunkLength)) CERROR_BREAK(state->error, 83 /*alloc fail*/); + for(i = 0; i < chunkLength; i++) idat.data[oldsize + i] = data[i]; +#ifdef LODEPNG_COMPILE_ANCILLARY_CHUNKS + critical_pos = 3; +#endif /*LODEPNG_COMPILE_ANCILLARY_CHUNKS*/ + } + /*IEND chunk*/ + else if(lodepng_chunk_type_equals(chunk, "IEND")) + { + IEND = 1; + } + /*palette chunk (PLTE)*/ + else if(lodepng_chunk_type_equals(chunk, "PLTE")) + { + unsigned pos = 0; + if(state->info_png.color.palette) myfree(state->info_png.color.palette); + state->info_png.color.palettesize = chunkLength / 3; + state->info_png.color.palette = (unsigned char*)mymalloc(4 * state->info_png.color.palettesize); + if(!state->info_png.color.palette && state->info_png.color.palettesize) + { + state->info_png.color.palettesize = 0; + CERROR_BREAK(state->error, 83); /*alloc fail*/ + } + if(state->info_png.color.palettesize > 256) CERROR_BREAK(state->error, 38); /*error: palette too big*/ + + for(i = 0; i < state->info_png.color.palettesize; i++) + { + state->info_png.color.palette[4 * i + 0] = data[pos++]; /*R*/ + state->info_png.color.palette[4 * i + 1] = data[pos++]; /*G*/ + state->info_png.color.palette[4 * i + 2] = data[pos++]; /*B*/ + state->info_png.color.palette[4 * i + 3] = 255; /*alpha*/ + } +#ifdef LODEPNG_COMPILE_ANCILLARY_CHUNKS + critical_pos = 2; +#endif /*LODEPNG_COMPILE_ANCILLARY_CHUNKS*/ + } + /*palette transparency chunk (tRNS)*/ + else if(lodepng_chunk_type_equals(chunk, "tRNS")) + { + if(state->info_png.color.colortype == LCT_PALETTE) + { + /*error: more alpha values given than there are palette entries*/ + if(chunkLength > state->info_png.color.palettesize) CERROR_BREAK(state->error, 38); + + for(i = 0; i < chunkLength; i++) state->info_png.color.palette[4 * i + 3] = data[i]; + } + else if(state->info_png.color.colortype == LCT_GREY) + { + /*error: this chunk must be 2 bytes for greyscale image*/ + if(chunkLength != 2) CERROR_BREAK(state->error, 30); + + state->info_png.color.key_defined = 1; + state->info_png.color.key_r = state->info_png.color.key_g + = state->info_png.color.key_b = 256 * data[0] + data[1]; + } + else if(state->info_png.color.colortype == LCT_RGB) + { + /*error: this chunk must be 6 bytes for RGB image*/ + if(chunkLength != 6) CERROR_BREAK(state->error, 41); + + state->info_png.color.key_defined = 1; + state->info_png.color.key_r = 256 * data[0] + data[1]; + state->info_png.color.key_g = 256 * data[2] + data[3]; + state->info_png.color.key_b = 256 * data[4] + data[5]; + } + else CERROR_BREAK(state->error, 42); /*error: tRNS chunk not allowed for other color models*/ + } +#ifdef LODEPNG_COMPILE_ANCILLARY_CHUNKS + /*background color chunk (bKGD)*/ + else if(lodepng_chunk_type_equals(chunk, "bKGD")) + { + if(state->info_png.color.colortype == LCT_PALETTE) + { + /*error: this chunk must be 1 byte for indexed color image*/ + if(chunkLength != 1) CERROR_BREAK(state->error, 43); + + state->info_png.background_defined = 1; + state->info_png.background_r = state->info_png.background_g = state->info_png.background_b = data[0]; + } + else if(state->info_png.color.colortype == LCT_GREY || state->info_png.color.colortype == LCT_GREY_ALPHA) + { + /*error: this chunk must be 2 bytes for greyscale image*/ + if(chunkLength != 2) CERROR_BREAK(state->error, 44); + + state->info_png.background_defined = 1; + state->info_png.background_r = state->info_png.background_g = state->info_png.background_b + = 256 * data[0] + data[1]; + } + else if(state->info_png.color.colortype == LCT_RGB || state->info_png.color.colortype == LCT_RGBA) + { + /*error: this chunk must be 6 bytes for greyscale image*/ + if(chunkLength != 6) CERROR_BREAK(state->error, 45); + + state->info_png.background_defined = 1; + state->info_png.background_r = 256 * data[0] + data[1]; + state->info_png.background_g = 256 * data[2] + data[3]; + state->info_png.background_b = 256 * data[4] + data[5]; + } + } + /*text chunk (tEXt)*/ + else if(lodepng_chunk_type_equals(chunk, "tEXt")) + { + if(state->decoder.read_text_chunks) + { + char *key = 0, *str = 0; + + while(!state->error) /*not really a while loop, only used to break on error*/ + { + unsigned length, string2_begin; + + length = 0; + while(length < chunkLength && data[length] != 0) length++; + /*error, end reached, no null terminator?*/ + if(length + 1 >= chunkLength) CERROR_BREAK(state->error, 75); + + key = (char*)mymalloc(length + 1); + if(!key) CERROR_BREAK(state->error, 83); /*alloc fail*/ + + key[length] = 0; + for(i = 0; i < length; i++) key[i] = data[i]; + + string2_begin = length + 1; + /*error, end reached, no null terminator?*/ + if(string2_begin > chunkLength) CERROR_BREAK(state->error, 75); + + length = chunkLength - string2_begin; + str = (char*)mymalloc(length + 1); + if(!str) CERROR_BREAK(state->error, 83); /*alloc fail*/ + + str[length] = 0; + for(i = 0; i < length; i++) str[i] = data[string2_begin + i]; + + state->error = lodepng_add_text(&state->info_png, key, str); + + break; + } + + myfree(key); + myfree(str); + } + } + /*compressed text chunk (zTXt)*/ + else if(lodepng_chunk_type_equals(chunk, "zTXt")) + { + if(state->decoder.read_text_chunks) + { + unsigned length, string2_begin; + char *key = 0; + ucvector decoded; + + ucvector_init(&decoded); + + while(!state->error) /*not really a while loop, only used to break on error*/ + { + for(length = 0; length < chunkLength && data[length] != 0; length++) ; + if(length + 2 >= chunkLength) CERROR_BREAK(state->error, 75); /*no null termination, corrupt?*/ + + key = (char*)mymalloc(length + 1); + if(!key) CERROR_BREAK(state->error, 83); /*alloc fail*/ + + key[length] = 0; + for(i = 0; i < length; i++) key[i] = data[i]; + + if(data[length + 1] != 0) CERROR_BREAK(state->error, 72); /*the 0 byte indicating compression must be 0*/ + + string2_begin = length + 2; + if(string2_begin > chunkLength) CERROR_BREAK(state->error, 75); /*no null termination, corrupt?*/ + + length = chunkLength - string2_begin; + state->error = lodepng_zlib_decompress(&decoded.data, &decoded.size, + (unsigned char*)(&data[string2_begin]), + length, &state->decoder.zlibsettings); + if(state->error) break; + ucvector_push_back(&decoded, 0); + + state->error = lodepng_add_text(&state->info_png, key, (char*)decoded.data); + + break; + } + + myfree(key); + ucvector_cleanup(&decoded); + if(state->error) break; + } + } + /*international text chunk (iTXt)*/ + else if(lodepng_chunk_type_equals(chunk, "iTXt")) + { + if(state->decoder.read_text_chunks) + { + unsigned length, begin, compressed; + char *key = 0, *langtag = 0, *transkey = 0; + ucvector decoded; + ucvector_init(&decoded); + + while(!state->error) /*not really a while loop, only used to break on error*/ + { + /*Quick check if the chunk length isn't too small. Even without check + it'd still fail with other error checks below if it's too short. This just gives a different error code.*/ + if(chunkLength < 5) CERROR_BREAK(state->error, 30); /*iTXt chunk too short*/ + + /*read the key*/ + for(length = 0; length < chunkLength && data[length] != 0; length++) ; + if(length + 2 >= chunkLength) CERROR_BREAK(state->error, 75); /*no null termination char found*/ + + key = (char*)mymalloc(length + 1); + if(!key) CERROR_BREAK(state->error, 83); /*alloc fail*/ + + key[length] = 0; + for(i = 0; i < length; i++) key[i] = data[i]; + + /*read the compression method*/ + compressed = data[length + 1]; + if(data[length + 2] != 0) CERROR_BREAK(state->error, 72); /*the 0 byte indicating compression must be 0*/ + + /*read the langtag*/ + begin = length + 3; + length = 0; + for(i = begin; i < chunkLength && data[i] != 0; i++) length++; + if(begin + length + 1 >= chunkLength) CERROR_BREAK(state->error, 75); /*no null termination char found*/ + + langtag = (char*)mymalloc(length + 1); + if(!langtag) CERROR_BREAK(state->error, 83); /*alloc fail*/ + + langtag[length] = 0; + for(i = 0; i < length; i++) langtag[i] = data[begin + i]; + + /*read the transkey*/ + begin += length + 1; + length = 0; + for(i = begin; i < chunkLength && data[i] != 0; i++) length++; + if(begin + length + 1 >= chunkLength) CERROR_BREAK(state->error, 75); /*no null termination, corrupt?*/ + + transkey = (char*)mymalloc(length + 1); + if(!transkey) CERROR_BREAK(state->error, 83); /*alloc fail*/ + + transkey[length] = 0; + for(i = 0; i < length; i++) transkey[i] = data[begin + i]; + + /*read the actual text*/ + begin += length + 1; + if(begin > chunkLength) CERROR_BREAK(state->error, 75); /*no null termination, corrupt?*/ + + length = chunkLength - begin; + + if(compressed) + { + state->error = lodepng_zlib_decompress(&decoded.data, &decoded.size, + (unsigned char*)(&data[begin]), + length, &state->decoder.zlibsettings); + if(state->error) break; + if(decoded.allocsize < decoded.size) decoded.allocsize = decoded.size; + ucvector_push_back(&decoded, 0); + } + else + { + if(!ucvector_resize(&decoded, length + 1)) CERROR_BREAK(state->error, 83 /*alloc fail*/); + + decoded.data[length] = 0; + for(i = 0; i < length; i++) decoded.data[i] = data[begin + i]; + } + + state->error = lodepng_add_itext(&state->info_png, key, langtag, transkey, (char*)decoded.data); + + break; + } + + myfree(key); + myfree(langtag); + myfree(transkey); + ucvector_cleanup(&decoded); + if(state->error) break; + } + } + else if(lodepng_chunk_type_equals(chunk, "tIME")) + { + if(chunkLength != 7) CERROR_BREAK(state->error, 73); /*invalid tIME chunk size*/ + + state->info_png.time_defined = 1; + state->info_png.time.year = 256 * data[0] + data[+ 1]; + state->info_png.time.month = data[2]; + state->info_png.time.day = data[3]; + state->info_png.time.hour = data[4]; + state->info_png.time.minute = data[5]; + state->info_png.time.second = data[6]; + } + else if(lodepng_chunk_type_equals(chunk, "pHYs")) + { + if(chunkLength != 9) CERROR_BREAK(state->error, 74); /*invalid pHYs chunk size*/ + + state->info_png.phys_defined = 1; + state->info_png.phys_x = 16777216 * data[0] + 65536 * data[1] + 256 * data[2] + data[3]; + state->info_png.phys_y = 16777216 * data[4] + 65536 * data[5] + 256 * data[6] + data[7]; + state->info_png.phys_unit = data[8]; + } +#endif /*LODEPNG_COMPILE_ANCILLARY_CHUNKS*/ + else /*it's not an implemented chunk type, so ignore it: skip over the data*/ + { + /*error: unknown critical chunk (5th bit of first byte of chunk type is 0)*/ + if(!lodepng_chunk_ancillary(chunk)) CERROR_BREAK(state->error, 69); + + unknown = 1; +#ifdef LODEPNG_COMPILE_ANCILLARY_CHUNKS + if(state->decoder.remember_unknown_chunks) + { + state->error = lodepng_chunk_append(&state->info_png.unknown_chunks_data[critical_pos - 1], + &state->info_png.unknown_chunks_size[critical_pos - 1], chunk); + if(state->error) break; + } +#endif /*LODEPNG_COMPILE_ANCILLARY_CHUNKS*/ + } + + if(!state->decoder.ignore_crc && !unknown) /*check CRC if wanted, only on known chunk types*/ + { + if(lodepng_chunk_check_crc(chunk)) CERROR_BREAK(state->error, 57); /*invalid CRC*/ + } + + if(!IEND) chunk = lodepng_chunk_next_const(chunk); + } + + if(!state->error) + { + ucvector scanlines; + ucvector_init(&scanlines); + + /*maximum final image length is already reserved in the vector's length - this is not really necessary*/ + if(!ucvector_resize(&scanlines, lodepng_get_raw_size(*w, *h, &state->info_png.color) + *h)) + { + state->error = 83; /*alloc fail*/ + } + if(!state->error) + { + /*decompress with the Zlib decompressor*/ + state->error = lodepng_zlib_decompress(&scanlines.data, &scanlines.size, idat.data, + idat.size, &state->decoder.zlibsettings); + } + + if(!state->error) + { + ucvector outv; + ucvector_init(&outv); + if(!ucvector_resizev(&outv, + lodepng_get_raw_size(*w, *h, &state->info_png.color), 0)) state->error = 83; /*alloc fail*/ + if(!state->error) state->error = postProcessScanlines(outv.data, scanlines.data, *w, *h, &state->info_png); + *out = outv.data; + } + ucvector_cleanup(&scanlines); + } + + ucvector_cleanup(&idat); +} + +unsigned lodepng_decode(unsigned char** out, unsigned* w, unsigned* h, + LodePNGState* state, + const unsigned char* in, size_t insize) +{ + *out = 0; + decodeGeneric(out, w, h, state, in, insize); + if(state->error) return state->error; + if(!state->decoder.color_convert || lodepng_color_mode_equal(&state->info_raw, &state->info_png.color)) + { + /*same color type, no copying or converting of data needed*/ + /*store the info_png color settings on the info_raw so that the info_raw still reflects what colortype + the raw image has to the end user*/ + if(!state->decoder.color_convert) + { + state->error = lodepng_color_mode_copy(&state->info_raw, &state->info_png.color); + if(state->error) return state->error; + } + } + else + { + /*color conversion needed; sort of copy of the data*/ + unsigned char* data = *out; + size_t outsize; + + /*TODO: check if this works according to the statement in the documentation: "The converter can convert + from greyscale input color type, to 8-bit greyscale or greyscale with alpha"*/ + if(!(state->info_raw.colortype == LCT_RGB || state->info_raw.colortype == LCT_RGBA) + && !(state->info_raw.bitdepth == 8)) + { + return 56; /*unsupported color mode conversion*/ + } + + outsize = lodepng_get_raw_size(*w, *h, &state->info_raw); + *out = (unsigned char*)mymalloc(outsize); + if(!(*out)) + { + state->error = 83; /*alloc fail*/ + } + else state->error = lodepng_convert(*out, data, &state->info_raw, &state->info_png.color, *w, *h); + myfree(data); + } + return state->error; +} + +unsigned lodepng_decode_memory(unsigned char** out, unsigned* w, unsigned* h, const unsigned char* in, + size_t insize, LodePNGColorType colortype, unsigned bitdepth) +{ + unsigned error; + LodePNGState state; + lodepng_state_init(&state); + state.info_raw.colortype = colortype; + state.info_raw.bitdepth = bitdepth; + error = lodepng_decode(out, w, h, &state, in, insize); + lodepng_state_cleanup(&state); + return error; +} + +unsigned lodepng_decode32(unsigned char** out, unsigned* w, unsigned* h, const unsigned char* in, size_t insize) +{ + return lodepng_decode_memory(out, w, h, in, insize, LCT_RGBA, 8); +} + +unsigned lodepng_decode24(unsigned char** out, unsigned* w, unsigned* h, const unsigned char* in, size_t insize) +{ + return lodepng_decode_memory(out, w, h, in, insize, LCT_RGB, 8); +} + +#ifdef LODEPNG_COMPILE_DISK +unsigned lodepng_decode_file(unsigned char** out, unsigned* w, unsigned* h, const char* filename, + LodePNGColorType colortype, unsigned bitdepth) +{ + unsigned char* buffer; + size_t buffersize; + unsigned error; + error = lodepng_load_file(&buffer, &buffersize, filename); + if(!error) error = lodepng_decode_memory(out, w, h, buffer, buffersize, colortype, bitdepth); + myfree(buffer); + return error; +} + +unsigned lodepng_decode32_file(unsigned char** out, unsigned* w, unsigned* h, const char* filename) +{ + return lodepng_decode_file(out, w, h, filename, LCT_RGBA, 8); +} + +unsigned lodepng_decode24_file(unsigned char** out, unsigned* w, unsigned* h, const char* filename) +{ + return lodepng_decode_file(out, w, h, filename, LCT_RGB, 8); +} +#endif /*LODEPNG_COMPILE_DISK*/ + +void lodepng_decoder_settings_init(LodePNGDecoderSettings* settings) +{ + settings->color_convert = 1; +#ifdef LODEPNG_COMPILE_ANCILLARY_CHUNKS + settings->read_text_chunks = 1; + settings->remember_unknown_chunks = 0; +#endif /*LODEPNG_COMPILE_ANCILLARY_CHUNKS*/ + settings->ignore_crc = 0; + lodepng_decompress_settings_init(&settings->zlibsettings); +} + +#endif /*LODEPNG_COMPILE_DECODER*/ + +#if defined(LODEPNG_COMPILE_DECODER) || defined(LODEPNG_COMPILE_ENCODER) + +void lodepng_state_init(LodePNGState* state) +{ +#ifdef LODEPNG_COMPILE_DECODER + lodepng_decoder_settings_init(&state->decoder); +#endif /*LODEPNG_COMPILE_DECODER*/ +#ifdef LODEPNG_COMPILE_ENCODER + lodepng_encoder_settings_init(&state->encoder); +#endif /*LODEPNG_COMPILE_ENCODER*/ + lodepng_color_mode_init(&state->info_raw); + lodepng_info_init(&state->info_png); + state->error = 1; +} + +void lodepng_state_cleanup(LodePNGState* state) +{ + lodepng_color_mode_cleanup(&state->info_raw); + lodepng_info_cleanup(&state->info_png); +} + +void lodepng_state_copy(LodePNGState* dest, const LodePNGState* source) +{ + lodepng_state_cleanup(dest); + *dest = *source; + lodepng_color_mode_init(&dest->info_raw); + lodepng_info_init(&dest->info_png); + dest->error = lodepng_color_mode_copy(&dest->info_raw, &source->info_raw); if(dest->error) return; + dest->error = lodepng_info_copy(&dest->info_png, &source->info_png); if(dest->error) return; +} + +#endif /* defined(LODEPNG_COMPILE_DECODER) || defined(LODEPNG_COMPILE_ENCODER) */ + +#ifdef LODEPNG_COMPILE_ENCODER + +/* ////////////////////////////////////////////////////////////////////////// */ +/* / PNG Encoder / */ +/* ////////////////////////////////////////////////////////////////////////// */ + +/*chunkName must be string of 4 characters*/ +static unsigned addChunk(ucvector* out, const char* chunkName, const unsigned char* data, size_t length) +{ + CERROR_TRY_RETURN(lodepng_chunk_create(&out->data, &out->size, (unsigned)length, chunkName, data)); + out->allocsize = out->size; /*fix the allocsize again*/ + return 0; +} + +static void writeSignature(ucvector* out) +{ + /*8 bytes PNG signature, aka the magic bytes*/ + ucvector_push_back(out, 137); + ucvector_push_back(out, 80); + ucvector_push_back(out, 78); + ucvector_push_back(out, 71); + ucvector_push_back(out, 13); + ucvector_push_back(out, 10); + ucvector_push_back(out, 26); + ucvector_push_back(out, 10); +} + +static unsigned addChunk_IHDR(ucvector* out, unsigned w, unsigned h, + LodePNGColorType colortype, unsigned bitdepth, unsigned interlace_method) +{ + unsigned error = 0; + ucvector header; + ucvector_init(&header); + + lodepng_add32bitInt(&header, w); /*width*/ + lodepng_add32bitInt(&header, h); /*height*/ + ucvector_push_back(&header, (unsigned char)bitdepth); /*bit depth*/ + ucvector_push_back(&header, (unsigned char)colortype); /*color type*/ + ucvector_push_back(&header, 0); /*compression method*/ + ucvector_push_back(&header, 0); /*filter method*/ + ucvector_push_back(&header, interlace_method); /*interlace method*/ + + error = addChunk(out, "IHDR", header.data, header.size); + ucvector_cleanup(&header); + + return error; +} + +static unsigned addChunk_PLTE(ucvector* out, const LodePNGColorMode* info) +{ + unsigned error = 0; + size_t i; + ucvector PLTE; + ucvector_init(&PLTE); + for(i = 0; i < info->palettesize * 4; i++) + { + /*add all channels except alpha channel*/ + if(i % 4 != 3) ucvector_push_back(&PLTE, info->palette[i]); + } + error = addChunk(out, "PLTE", PLTE.data, PLTE.size); + ucvector_cleanup(&PLTE); + + return error; +} + +static unsigned addChunk_tRNS(ucvector* out, const LodePNGColorMode* info) +{ + unsigned error = 0; + size_t i; + ucvector tRNS; + ucvector_init(&tRNS); + if(info->colortype == LCT_PALETTE) + { + size_t amount = info->palettesize; + /*the tail of palette values that all have 255 as alpha, does not have to be encoded*/ + for(i = info->palettesize; i > 0; i--) + { + if(info->palette[4 * (i - 1) + 3] == 255) amount--; + else break; + } + /*add only alpha channel*/ + for(i = 0; i < amount; i++) ucvector_push_back(&tRNS, info->palette[4 * i + 3]); + } + else if(info->colortype == LCT_GREY) + { + if(info->key_defined) + { + ucvector_push_back(&tRNS, (unsigned char)(info->key_r / 256)); + ucvector_push_back(&tRNS, (unsigned char)(info->key_r % 256)); + } + } + else if(info->colortype == LCT_RGB) + { + if(info->key_defined) + { + ucvector_push_back(&tRNS, (unsigned char)(info->key_r / 256)); + ucvector_push_back(&tRNS, (unsigned char)(info->key_r % 256)); + ucvector_push_back(&tRNS, (unsigned char)(info->key_g / 256)); + ucvector_push_back(&tRNS, (unsigned char)(info->key_g % 256)); + ucvector_push_back(&tRNS, (unsigned char)(info->key_b / 256)); + ucvector_push_back(&tRNS, (unsigned char)(info->key_b % 256)); + } + } + + error = addChunk(out, "tRNS", tRNS.data, tRNS.size); + ucvector_cleanup(&tRNS); + + return error; +} + +static unsigned addChunk_IDAT(ucvector* out, const unsigned char* data, size_t datasize, + LodePNGCompressSettings* zlibsettings) +{ + ucvector zlibdata; + unsigned error = 0; + + /*compress with the Zlib compressor*/ + ucvector_init(&zlibdata); + error = lodepng_zlib_compress(&zlibdata.data, &zlibdata.size, data, datasize, zlibsettings); + if(!error) error = addChunk(out, "IDAT", zlibdata.data, zlibdata.size); + ucvector_cleanup(&zlibdata); + + return error; +} + +static unsigned addChunk_IEND(ucvector* out) +{ + unsigned error = 0; + error = addChunk(out, "IEND", 0, 0); + return error; +} + +#ifdef LODEPNG_COMPILE_ANCILLARY_CHUNKS + +static unsigned addChunk_tEXt(ucvector* out, const char* keyword, const char* textstring) +{ + unsigned error = 0; + size_t i; + ucvector text; + ucvector_init(&text); + for(i = 0; keyword[i] != 0; i++) ucvector_push_back(&text, (unsigned char)keyword[i]); + ucvector_push_back(&text, 0); + for(i = 0; textstring[i] != 0; i++) ucvector_push_back(&text, (unsigned char)textstring[i]); + error = addChunk(out, "tEXt", text.data, text.size); + ucvector_cleanup(&text); + + return error; +} + +static unsigned addChunk_zTXt(ucvector* out, const char* keyword, const char* textstring, + LodePNGCompressSettings* zlibsettings) +{ + unsigned error = 0; + ucvector data, compressed; + size_t i, textsize = strlen(textstring); + + ucvector_init(&data); + ucvector_init(&compressed); + for(i = 0; keyword[i] != 0; i++) ucvector_push_back(&data, (unsigned char)keyword[i]); + ucvector_push_back(&data, 0); /*0 termination char*/ + ucvector_push_back(&data, 0); /*compression method: 0*/ + + error = lodepng_zlib_compress(&compressed.data, &compressed.size, + (unsigned char*)textstring, textsize, zlibsettings); + if(!error) + { + for(i = 0; i < compressed.size; i++) ucvector_push_back(&data, compressed.data[i]); + error = addChunk(out, "zTXt", data.data, data.size); + } + + ucvector_cleanup(&compressed); + ucvector_cleanup(&data); + return error; +} + +static unsigned addChunk_iTXt(ucvector* out, unsigned compressed, const char* keyword, const char* langtag, + const char* transkey, const char* textstring, LodePNGCompressSettings* zlibsettings) +{ + unsigned error = 0; + ucvector data; + size_t i, textsize = strlen(textstring); + + ucvector_init(&data); + + for(i = 0; keyword[i] != 0; i++) ucvector_push_back(&data, (unsigned char)keyword[i]); + ucvector_push_back(&data, 0); /*null termination char*/ + ucvector_push_back(&data, compressed ? 1 : 0); /*compression flag*/ + ucvector_push_back(&data, 0); /*compression method*/ + for(i = 0; langtag[i] != 0; i++) ucvector_push_back(&data, (unsigned char)langtag[i]); + ucvector_push_back(&data, 0); /*null termination char*/ + for(i = 0; transkey[i] != 0; i++) ucvector_push_back(&data, (unsigned char)transkey[i]); + ucvector_push_back(&data, 0); /*null termination char*/ + + if(compressed) + { + ucvector compressed_data; + ucvector_init(&compressed_data); + error = lodepng_zlib_compress(&compressed_data.data, &compressed_data.size, + (unsigned char*)textstring, textsize, zlibsettings); + if(!error) + { + for(i = 0; i < compressed_data.size; i++) ucvector_push_back(&data, compressed_data.data[i]); + } + ucvector_cleanup(&compressed_data); + } + else /*not compressed*/ + { + for(i = 0; textstring[i] != 0; i++) ucvector_push_back(&data, (unsigned char)textstring[i]); + } + + if(!error) error = addChunk(out, "iTXt", data.data, data.size); + ucvector_cleanup(&data); + return error; +} + +static unsigned addChunk_bKGD(ucvector* out, const LodePNGInfo* info) +{ + unsigned error = 0; + ucvector bKGD; + ucvector_init(&bKGD); + if(info->color.colortype == LCT_GREY || info->color.colortype == LCT_GREY_ALPHA) + { + ucvector_push_back(&bKGD, (unsigned char)(info->background_r / 256)); + ucvector_push_back(&bKGD, (unsigned char)(info->background_r % 256)); + } + else if(info->color.colortype == LCT_RGB || info->color.colortype == LCT_RGBA) + { + ucvector_push_back(&bKGD, (unsigned char)(info->background_r / 256)); + ucvector_push_back(&bKGD, (unsigned char)(info->background_r % 256)); + ucvector_push_back(&bKGD, (unsigned char)(info->background_g / 256)); + ucvector_push_back(&bKGD, (unsigned char)(info->background_g % 256)); + ucvector_push_back(&bKGD, (unsigned char)(info->background_b / 256)); + ucvector_push_back(&bKGD, (unsigned char)(info->background_b % 256)); + } + else if(info->color.colortype == LCT_PALETTE) + { + ucvector_push_back(&bKGD, (unsigned char)(info->background_r % 256)); /*palette index*/ + } + + error = addChunk(out, "bKGD", bKGD.data, bKGD.size); + ucvector_cleanup(&bKGD); + + return error; +} + +static unsigned addChunk_tIME(ucvector* out, const LodePNGTime* time) +{ + unsigned error = 0; + unsigned char* data = (unsigned char*)mymalloc(7); + if(!data) return 83; /*alloc fail*/ + data[0] = (unsigned char)(time->year / 256); + data[1] = (unsigned char)(time->year % 256); + data[2] = time->month; + data[3] = time->day; + data[4] = time->hour; + data[5] = time->minute; + data[6] = time->second; + error = addChunk(out, "tIME", data, 7); + myfree(data); + return error; +} + +static unsigned addChunk_pHYs(ucvector* out, const LodePNGInfo* info) +{ + unsigned error = 0; + ucvector data; + ucvector_init(&data); + + lodepng_add32bitInt(&data, info->phys_x); + lodepng_add32bitInt(&data, info->phys_y); + ucvector_push_back(&data, info->phys_unit); + + error = addChunk(out, "pHYs", data.data, data.size); + ucvector_cleanup(&data); + + return error; +} + +#endif /*LODEPNG_COMPILE_ANCILLARY_CHUNKS*/ + +static void filterScanline(unsigned char* out, const unsigned char* scanline, const unsigned char* prevline, + size_t length, size_t bytewidth, unsigned char filterType) +{ + size_t i; + switch(filterType) + { + case 0: /*None*/ + for(i = 0; i < length; i++) out[i] = scanline[i]; + break; + case 1: /*Sub*/ + if(prevline) + { + for(i = 0; i < bytewidth; i++) out[i] = scanline[i]; + for(i = bytewidth; i < length; i++) out[i] = scanline[i] - scanline[i - bytewidth]; + } + else + { + for(i = 0; i < bytewidth; i++) out[i] = scanline[i]; + for(i = bytewidth; i < length; i++) out[i] = scanline[i] - scanline[i - bytewidth]; + } + break; + case 2: /*Up*/ + if(prevline) + { + for(i = 0; i < length; i++) out[i] = scanline[i] - prevline[i]; + } + else + { + for(i = 0; i < length; i++) out[i] = scanline[i]; + } + break; + case 3: /*Average*/ + if(prevline) + { + for(i = 0; i < bytewidth; i++) out[i] = scanline[i] - prevline[i] / 2; + for(i = bytewidth; i < length; i++) out[i] = scanline[i] - ((scanline[i - bytewidth] + prevline[i]) / 2); + } + else + { + for(i = 0; i < bytewidth; i++) out[i] = scanline[i]; + for(i = bytewidth; i < length; i++) out[i] = scanline[i] - scanline[i - bytewidth] / 2; + } + break; + case 4: /*Paeth*/ + if(prevline) + { + /*paethPredictor(0, prevline[i], 0) is always prevline[i]*/ + for(i = 0; i < bytewidth; i++) out[i] = (scanline[i] - prevline[i]); + for(i = bytewidth; i < length; i++) + { + out[i] = (scanline[i] - paethPredictor(scanline[i - bytewidth], prevline[i], prevline[i - bytewidth])); + } + } + else + { + for(i = 0; i < bytewidth; i++) out[i] = scanline[i]; + /*paethPredictor(scanline[i - bytewidth], 0, 0) is always scanline[i - bytewidth]*/ + for(i = bytewidth; i < length; i++) out[i] = (scanline[i] - scanline[i - bytewidth]); + } + break; + default: return; /*unexisting filter type given*/ + } +} + +static unsigned filter(unsigned char* out, const unsigned char* in, unsigned w, unsigned h, + const LodePNGColorMode* info, const LodePNGEncoderSettings* settings) +{ + /* + For PNG filter method 0 + out must be a buffer with as size: h + (w * h * bpp + 7) / 8, because there are + the scanlines with 1 extra byte per scanline + */ + + unsigned bpp = lodepng_get_bpp(info); + /*the width of a scanline in bytes, not including the filter type*/ + size_t linebytes = (w * bpp + 7) / 8; + /*bytewidth is used for filtering, is 1 when bpp < 8, number of bytes per pixel otherwise*/ + size_t bytewidth = (bpp + 7) / 8; + const unsigned char* prevline = 0; + unsigned x, y; + unsigned error = 0; + /* + There is a heuristic called the minimum sum of absolute differences heuristic, suggested by the PNG standard: + * If the image type is Palette, or the bit depth is smaller than 8, then do not filter the image (i.e. + use fixed filtering, with the filter None). + * (The other case) If the image type is Grayscale or RGB (with or without Alpha), and the bit depth is + not smaller than 8, then use adaptive filtering heuristic as follows: independently for each row, apply + all five filters and select the filter that produces the smallest sum of absolute values per row. + This heuristic is used if filter strategy is LFS_HEURISTIC. Parts of it are used for filter strategies + LFS_MINSUM and LFS_ZERO. + */ + int heuristic_zero = info->colortype == LCT_PALETTE || info->bitdepth < 8; + + if(bpp == 0) return 31; /*error: invalid color type*/ + + if((!heuristic_zero && settings->filter_strategy == LFS_HEURISTIC)|| + settings->filter_strategy == LFS_MINSUM) + { + /*adaptive filtering*/ + size_t sum[5]; + ucvector attempt[5]; /*five filtering attempts, one for each filter type*/ + size_t smallest = 0; + unsigned type, bestType = 0; + + for(type = 0; type < 5; type++) ucvector_init(&attempt[type]); + + for(type = 0; type < 5; type++) + { + if(!ucvector_resize(&attempt[type], linebytes)) ERROR_BREAK(83 /*alloc fail*/); + } + + if(!error) + { + for(y = 0; y < h; y++) + { + /*try the 5 filter types*/ + for(type = 0; type < 5; type++) + { + filterScanline(attempt[type].data, &in[y * linebytes], prevline, linebytes, bytewidth, type); + + /*calculate the sum of the result*/ + sum[type] = 0; + /*note that not all pixels are checked to speed this up while still having probably the best choice*/ + for(x = 0; x < attempt[type].size; x+=3) + { + /*For differences, each byte should be treated as signed, values above 127 are negative + (converted to signed char). Filtertype 0 isn't a difference though, so use unsigned there. + This means filtertype 0 is almost never chosen, but that is justified.*/ + if(type == 0) sum[type] += (unsigned char)(attempt[type].data[x]); + else + { + signed char s = (signed char)(attempt[type].data[x]); + sum[type] += s < 0 ? -s : s; + } + } + + /*check if this is smallest sum (or if type == 0 it's the first case so always store the values)*/ + if(type == 0 || sum[type] < smallest) + { + bestType = type; + smallest = sum[type]; + } + } + + prevline = &in[y * linebytes]; + + /*now fill the out values*/ + out[y * (linebytes + 1)] = bestType; /*the first byte of a scanline will be the filter type*/ + for(x = 0; x < linebytes; x++) out[y * (linebytes + 1) + 1 + x] = attempt[bestType].data[x]; + } + } + + for(type = 0; type < 5; type++) ucvector_cleanup(&attempt[type]); + } + else if((heuristic_zero && settings->filter_strategy == LFS_HEURISTIC)|| + settings->filter_strategy == LFS_ZERO) + { + for(y = 0; y < h; y++) + { + size_t outindex = (1 + linebytes) * y; /*the extra filterbyte added to each row*/ + size_t inindex = linebytes * y; + const unsigned TYPE = 0; + out[outindex] = TYPE; /*filter type byte*/ + filterScanline(&out[outindex + 1], &in[inindex], prevline, linebytes, bytewidth, TYPE); + prevline = &in[inindex]; + } + } + else if(settings->filter_strategy == LFS_PREDEFINED) + { + for(y = 0; y < h; y++) + { + size_t outindex = (1 + linebytes) * y; /*the extra filterbyte added to each row*/ + size_t inindex = linebytes * y; + unsigned type = settings->predefined_filters[y]; + out[outindex] = type; /*filter type byte*/ + filterScanline(&out[outindex + 1], &in[inindex], prevline, linebytes, bytewidth, type); + prevline = &in[inindex]; + } + } + else /*LFS_BRUTE_FORCE*/ + { + /*brute force filter chooser. + deflate the scanline after every filter attempt to see which one deflates best. + This is very slow and gives only slightly smaller, sometimes even larger, result*/ + size_t size[5]; + ucvector attempt[5]; /*five filtering attempts, one for each filter type*/ + size_t smallest = 0; + unsigned type = 0, bestType = 0; + unsigned char* dummy; + LodePNGCompressSettings zlibsettings = settings->zlibsettings; + /*use fixed tree on the attempts so that the tree is not adapted to the filtertype on purpose, + to simulate the true case where the tree is the same for the whole image. Sometimes it gives + better result with dynamic tree anyway. Using the fixed tree sometimes gives worse, but in rare + cases better compression. It does make this a bit less slow, so it's worth doing this.*/ + zlibsettings.btype = 1; + /*a custom encoder likely doesn't read the btype setting and is optimized for complete PNG + images only, so disable it*/ + zlibsettings.custom_encoder = 0; + for(type = 0; type < 5; type++) + { + ucvector_init(&attempt[type]); + ucvector_resize(&attempt[type], linebytes); /*todo: give error if resize failed*/ + } + for(y = 0; y < h; y++) /*try the 5 filter types*/ + { + for(type = 0; type < 5; type++) + { + unsigned testsize = attempt[type].size; + /*if(testsize > 8) testsize /= 8;*/ /*it already works good enough by testing a part of the row*/ + + filterScanline(attempt[type].data, &in[y * linebytes], prevline, linebytes, bytewidth, type); + size[type] = 0; + dummy = 0; + lodepng_zlib_compress(&dummy, &size[type], attempt[type].data, testsize, &zlibsettings); + myfree(dummy); + /*check if this is smallest size (or if type == 0 it's the first case so always store the values)*/ + if(type == 0 || size[type] < smallest) + { + bestType = type; + smallest = size[type]; + } + } + prevline = &in[y * linebytes]; + out[y * (linebytes + 1)] = bestType; /*the first byte of a scanline will be the filter type*/ + for(x = 0; x < linebytes; x++) out[y * (linebytes + 1) + 1 + x] = attempt[bestType].data[x]; + } + for(type = 0; type < 5; type++) ucvector_cleanup(&attempt[type]); + } + + return error; +} + +static void addPaddingBits(unsigned char* out, const unsigned char* in, + size_t olinebits, size_t ilinebits, unsigned h) +{ + /*The opposite of the removePaddingBits function + olinebits must be >= ilinebits*/ + unsigned y; + size_t diff = olinebits - ilinebits; + size_t obp = 0, ibp = 0; /*bit pointers*/ + for(y = 0; y < h; y++) + { + size_t x; + for(x = 0; x < ilinebits; x++) + { + unsigned char bit = readBitFromReversedStream(&ibp, in); + setBitOfReversedStream(&obp, out, bit); + } + /*obp += diff; --> no, fill in some value in the padding bits too, to avoid + "Use of uninitialised value of size ###" warning from valgrind*/ + for(x = 0; x < diff; x++) setBitOfReversedStream(&obp, out, 0); + } +} + +static void Adam7_interlace(unsigned char* out, const unsigned char* in, unsigned w, unsigned h, unsigned bpp) +{ + /*Note: this function works on image buffers WITHOUT padding bits at end of scanlines with non-multiple-of-8 + bit amounts, only between reduced images is padding*/ + unsigned passw[7], passh[7]; + size_t filter_passstart[8], padded_passstart[8], passstart[8]; + unsigned i; + + Adam7_getpassvalues(passw, passh, filter_passstart, padded_passstart, passstart, w, h, bpp); + + if(bpp >= 8) + { + for(i = 0; i < 7; i++) + { + unsigned x, y, b; + size_t bytewidth = bpp / 8; + for(y = 0; y < passh[i]; y++) + for(x = 0; x < passw[i]; x++) + { + size_t pixelinstart = ((ADAM7_IY[i] + y * ADAM7_DY[i]) * w + ADAM7_IX[i] + x * ADAM7_DX[i]) * bytewidth; + size_t pixeloutstart = passstart[i] + (y * passw[i] + x) * bytewidth; + for(b = 0; b < bytewidth; b++) + { + out[pixeloutstart + b] = in[pixelinstart + b]; + } + } + } + } + else /*bpp < 8: Adam7 with pixels < 8 bit is a bit trickier: with bit pointers*/ + { + for(i = 0; i < 7; i++) + { + unsigned x, y, b; + unsigned ilinebits = bpp * passw[i]; + unsigned olinebits = bpp * w; + size_t obp, ibp; /*bit pointers (for out and in buffer)*/ + for(y = 0; y < passh[i]; y++) + for(x = 0; x < passw[i]; x++) + { + ibp = (ADAM7_IY[i] + y * ADAM7_DY[i]) * olinebits + (ADAM7_IX[i] + x * ADAM7_DX[i]) * bpp; + obp = (8 * passstart[i]) + (y * ilinebits + x * bpp); + for(b = 0; b < bpp; b++) + { + unsigned char bit = readBitFromReversedStream(&ibp, in); + setBitOfReversedStream(&obp, out, bit); + } + } + } + } +} + +/*out must be buffer big enough to contain uncompressed IDAT chunk data, and in must contain the full image. +return value is error**/ +static unsigned preProcessScanlines(unsigned char** out, size_t* outsize, const unsigned char* in, + unsigned w, unsigned h, + const LodePNGInfo* info_png, const LodePNGEncoderSettings* settings) +{ + /* + This function converts the pure 2D image with the PNG's colortype, into filtered-padded-interlaced data. Steps: + *) if no Adam7: 1) add padding bits (= posible extra bits per scanline if bpp < 8) 2) filter + *) if adam7: 1) Adam7_interlace 2) 7x add padding bits 3) 7x filter + */ + unsigned bpp = lodepng_get_bpp(&info_png->color); + unsigned error = 0; + + if(info_png->interlace_method == 0) + { + *outsize = h + (h * ((w * bpp + 7) / 8)); /*image size plus an extra byte per scanline + possible padding bits*/ + *out = (unsigned char*)mymalloc(*outsize); + if(!(*out) && (*outsize)) error = 83; /*alloc fail*/ + + if(!error) + { + /*non multiple of 8 bits per scanline, padding bits needed per scanline*/ + if(bpp < 8 && w * bpp != ((w * bpp + 7) / 8) * 8) + { + ucvector padded; + ucvector_init(&padded); + if(!ucvector_resize(&padded, h * ((w * bpp + 7) / 8))) error = 83; /*alloc fail*/ + if(!error) + { + addPaddingBits(padded.data, in, ((w * bpp + 7) / 8) * 8, w * bpp, h); + error = filter(*out, padded.data, w, h, &info_png->color, settings); + } + ucvector_cleanup(&padded); + } + else + { + /*we can immediatly filter into the out buffer, no other steps needed*/ + error = filter(*out, in, w, h, &info_png->color, settings); + } + } + } + else /*interlace_method is 1 (Adam7)*/ + { + unsigned char* adam7 = (unsigned char*)mymalloc((h * w * bpp + 7) / 8); + if(!adam7 && ((h * w * bpp + 7) / 8)) error = 83; /*alloc fail*/ + + while(!error) /*not a real while loop, used to break out to cleanup to avoid a goto*/ + { + unsigned passw[7], passh[7]; + size_t filter_passstart[8], padded_passstart[8], passstart[8]; + unsigned i; + + Adam7_getpassvalues(passw, passh, filter_passstart, padded_passstart, passstart, w, h, bpp); + + *outsize = filter_passstart[7]; /*image size plus an extra byte per scanline + possible padding bits*/ + *out = (unsigned char*)mymalloc(*outsize); + if(!(*out) && (*outsize)) ERROR_BREAK(83 /*alloc fail*/); + + Adam7_interlace(adam7, in, w, h, bpp); + + for(i = 0; i < 7; i++) + { + if(bpp < 8) + { + ucvector padded; + ucvector_init(&padded); + if(!ucvector_resize(&padded, h * ((w * bpp + 7) / 8))) error = 83; /*alloc fail*/ + if(!error) + { + addPaddingBits(&padded.data[padded_passstart[i]], &adam7[passstart[i]], + ((passw[i] * bpp + 7) / 8) * 8, passw[i] * bpp, passh[i]); + error = filter(&(*out)[filter_passstart[i]], &padded.data[padded_passstart[i]], + passw[i], passh[i], &info_png->color, settings); + } + + ucvector_cleanup(&padded); + } + else + { + error = filter(&(*out)[filter_passstart[i]], &adam7[padded_passstart[i]], + passw[i], passh[i], &info_png->color, settings); + } + } + + break; + } + + myfree(adam7); + } + + return error; +} + +/* +palette must have 4 * palettesize bytes allocated, and given in format RGBARGBARGBARGBA... +returns 0 if the palette is opaque, +returns 1 if the palette has a single color with alpha 0 ==> color key +returns 2 if the palette is semi-translucent. +*/ +static unsigned getPaletteTranslucency(const unsigned char* palette, size_t palettesize) +{ + size_t i, key = 0; + unsigned r, g, b; /*the value of the color with alpha 0, so long as color keying is possible*/ + for(i = 0; i < palettesize; i++) + { + if(!key && palette[4 * i + 3] == 0) + { + r = palette[4 * i + 0]; g = palette[4 * i + 1]; b = palette[4 * i + 2]; + key = 1; + i = (size_t)(-1); /*restart from beginning, to detect earlier opaque colors with key's value*/ + } + else if(palette[4 * i + 3] != 255) return 2; + /*when key, no opaque RGB may have key's RGB*/ + else if(key && r == palette[i * 4 + 0] && g == palette[i * 4 + 1] && b == palette[i * 4 + 2]) return 2; + } + return key; +} + +#ifdef LODEPNG_COMPILE_ANCILLARY_CHUNKS +static unsigned addUnknownChunks(ucvector* out, unsigned char* data, size_t datasize) +{ + unsigned char* inchunk = data; + while((size_t)(inchunk - data) < datasize) + { + CERROR_TRY_RETURN(lodepng_chunk_append(&out->data, &out->size, inchunk)); + out->allocsize = out->size; /*fix the allocsize again*/ + inchunk = lodepng_chunk_next(inchunk); + } + return 0; +} +#endif /*LODEPNG_COMPILE_ANCILLARY_CHUNKS*/ + +unsigned lodepng_encode(unsigned char** out, size_t* outsize, + const unsigned char* image, unsigned w, unsigned h, + LodePNGState* state) +{ + LodePNGInfo info; + ucvector outv; + unsigned char* data = 0; /*uncompressed version of the IDAT chunk data*/ + size_t datasize = 0; + + /*provide some proper output values if error will happen*/ + *out = 0; + *outsize = 0; + state->error = 0; + + lodepng_info_init(&info); + lodepng_info_copy(&info, &state->info_png); + + if((info.color.colortype == LCT_PALETTE || state->encoder.force_palette) + && (info.color.palettesize == 0 || info.color.palettesize > 256)) + { + state->error = 68; /*invalid palette size, it is only allowed to be 1-256*/ + return state->error; + } + + if(state->encoder.auto_convert != LAC_NO) + { + state->error = doAutoChooseColor(&info.color, image, w, h, &state->info_raw, + state->encoder.auto_convert); + } + if(state->error) return state->error; + + if(state->encoder.zlibsettings.windowsize > 32768) + { + CERROR_RETURN_ERROR(state->error, 60); /*error: windowsize larger than allowed*/ + } + if(state->encoder.zlibsettings.btype > 2) + { + CERROR_RETURN_ERROR(state->error, 61); /*error: unexisting btype*/ + } + if(state->info_png.interlace_method > 1) + { + CERROR_RETURN_ERROR(state->error, 71); /*error: unexisting interlace mode*/ + } + /*error: unexisting color type given*/ + if((state->error = checkColorValidity(info.color.colortype, info.color.bitdepth))) return state->error; + /*error: unexisting color type given*/ + if((state->error = checkColorValidity(state->info_raw.colortype, state->info_raw.bitdepth))) return state->error; + + if(!lodepng_color_mode_equal(&state->info_raw, &info.color)) + { + unsigned char* converted; + size_t size = (w * h * lodepng_get_bpp(&info.color) + 7) / 8; + + converted = (unsigned char*)mymalloc(size); + if(!converted && size) state->error = 83; /*alloc fail*/ + if(!state->error) + { + state->error = lodepng_convert(converted, image, &info.color, &state->info_raw, w, h); + } + if(!state->error) preProcessScanlines(&data, &datasize, converted, w, h, &info, &state->encoder); + myfree(converted); + } + else preProcessScanlines(&data, &datasize, image, w, h, &info, &state->encoder); + + ucvector_init(&outv); + while(!state->error) /*while only executed once, to break on error*/ + { +#ifdef LODEPNG_COMPILE_ANCILLARY_CHUNKS + size_t i; +#endif /*LODEPNG_COMPILE_ANCILLARY_CHUNKS*/ + /*write signature and chunks*/ + writeSignature(&outv); + /*IHDR*/ + addChunk_IHDR(&outv, w, h, info.color.colortype, info.color.bitdepth, info.interlace_method); +#ifdef LODEPNG_COMPILE_ANCILLARY_CHUNKS + /*unknown chunks between IHDR and PLTE*/ + if(info.unknown_chunks_data[0]) + { + state->error = addUnknownChunks(&outv, info.unknown_chunks_data[0], info.unknown_chunks_size[0]); + if(state->error) break; + } +#endif /*LODEPNG_COMPILE_ANCILLARY_CHUNKS*/ + /*PLTE*/ + if(info.color.colortype == LCT_PALETTE) + { + addChunk_PLTE(&outv, &info.color); + } + if(state->encoder.force_palette && (info.color.colortype == LCT_RGB || info.color.colortype == LCT_RGBA)) + { + addChunk_PLTE(&outv, &info.color); + } + /*tRNS*/ + if(info.color.colortype == LCT_PALETTE && getPaletteTranslucency(info.color.palette, info.color.palettesize) != 0) + { + addChunk_tRNS(&outv, &info.color); + } + if((info.color.colortype == LCT_GREY || info.color.colortype == LCT_RGB) && info.color.key_defined) + { + addChunk_tRNS(&outv, &info.color); + } +#ifdef LODEPNG_COMPILE_ANCILLARY_CHUNKS + /*bKGD (must come between PLTE and the IDAt chunks*/ + if(info.background_defined) addChunk_bKGD(&outv, &info); + /*pHYs (must come before the IDAT chunks)*/ + if(info.phys_defined) addChunk_pHYs(&outv, &info); + + /*unknown chunks between PLTE and IDAT*/ + if(info.unknown_chunks_data[1]) + { + state->error = addUnknownChunks(&outv, info.unknown_chunks_data[1], info.unknown_chunks_size[1]); + if(state->error) break; + } +#endif /*LODEPNG_COMPILE_ANCILLARY_CHUNKS*/ + /*IDAT (multiple IDAT chunks must be consecutive)*/ + state->error = addChunk_IDAT(&outv, data, datasize, &state->encoder.zlibsettings); + if(state->error) break; +#ifdef LODEPNG_COMPILE_ANCILLARY_CHUNKS + /*tIME*/ + if(info.time_defined) addChunk_tIME(&outv, &info.time); + /*tEXt and/or zTXt*/ + for(i = 0; i < info.text_num; i++) + { + if(strlen(info.text_keys[i]) > 79) + { + state->error = 66; /*text chunk too large*/ + break; + } + if(strlen(info.text_keys[i]) < 1) + { + state->error = 67; /*text chunk too small*/ + break; + } + if(state->encoder.text_compression) + addChunk_zTXt(&outv, info.text_keys[i], info.text_strings[i], &state->encoder.zlibsettings); + else + addChunk_tEXt(&outv, info.text_keys[i], info.text_strings[i]); + } + /*LodePNG version id in text chunk*/ + if(state->encoder.add_id) + { + unsigned alread_added_id_text = 0; + for(i = 0; i < info.text_num; i++) + { + if(!strcmp(info.text_keys[i], "LodePNG")) + { + alread_added_id_text = 1; + break; + } + } + if(alread_added_id_text == 0) + addChunk_tEXt(&outv, "LodePNG", VERSION_STRING); /*it's shorter as tEXt than as zTXt chunk*/ + } + /*iTXt*/ + for(i = 0; i < info.itext_num; i++) + { + if(strlen(info.itext_keys[i]) > 79) + { + state->error = 66; /*text chunk too large*/ + break; + } + if(strlen(info.itext_keys[i]) < 1) + { + state->error = 67; /*text chunk too small*/ + break; + } + addChunk_iTXt(&outv, state->encoder.text_compression, + info.itext_keys[i], info.itext_langtags[i], info.itext_transkeys[i], info.itext_strings[i], + &state->encoder.zlibsettings); + } + + /*unknown chunks between IDAT and IEND*/ + if(info.unknown_chunks_data[2]) + { + state->error = addUnknownChunks(&outv, info.unknown_chunks_data[2], info.unknown_chunks_size[2]); + if(state->error) break; + } +#endif /*LODEPNG_COMPILE_ANCILLARY_CHUNKS*/ + /*IEND*/ + addChunk_IEND(&outv); + + break; /*this isn't really a while loop; no error happened so break out now!*/ + } + + lodepng_info_cleanup(&info); + myfree(data); + /*instead of cleaning the vector up, give it to the output*/ + *out = outv.data; + *outsize = outv.size; + + return state->error; +} + +unsigned lodepng_encode_memory(unsigned char** out, size_t* outsize, const unsigned char* image, + unsigned w, unsigned h, LodePNGColorType colortype, unsigned bitdepth) +{ + unsigned error; + LodePNGState state; + lodepng_state_init(&state); + state.info_raw.colortype = colortype; + state.info_raw.bitdepth = bitdepth; + state.info_png.color.colortype = colortype; + state.info_png.color.bitdepth = bitdepth; + lodepng_encode(out, outsize, image, w, h, &state); + error = state.error; + lodepng_state_cleanup(&state); + return error; +} + +unsigned lodepng_encode32(unsigned char** out, size_t* outsize, const unsigned char* image, unsigned w, unsigned h) +{ + return lodepng_encode_memory(out, outsize, image, w, h, LCT_RGBA, 8); +} + +unsigned lodepng_encode24(unsigned char** out, size_t* outsize, const unsigned char* image, unsigned w, unsigned h) +{ + return lodepng_encode_memory(out, outsize, image, w, h, LCT_RGB, 8); +} + +#ifdef LODEPNG_COMPILE_DISK +unsigned lodepng_encode_file(const char* filename, const unsigned char* image, unsigned w, unsigned h, + LodePNGColorType colortype, unsigned bitdepth) +{ + unsigned char* buffer; + size_t buffersize; + unsigned error = lodepng_encode_memory(&buffer, &buffersize, image, w, h, colortype, bitdepth); + if(!error) error = lodepng_save_file(buffer, buffersize, filename); + myfree(buffer); + return error; +} + +unsigned lodepng_encode32_file(const char* filename, const unsigned char* image, unsigned w, unsigned h) +{ + return lodepng_encode_file(filename, image, w, h, LCT_RGBA, 8); +} + +unsigned lodepng_encode24_file(const char* filename, const unsigned char* image, unsigned w, unsigned h) +{ + return lodepng_encode_file(filename, image, w, h, LCT_RGB, 8); +} +#endif /*LODEPNG_COMPILE_DISK*/ + +void lodepng_encoder_settings_init(LodePNGEncoderSettings* settings) +{ + lodepng_compress_settings_init(&settings->zlibsettings); + settings->filter_strategy = LFS_HEURISTIC; + settings->auto_convert = LAC_AUTO; + settings->force_palette = 0; + settings->predefined_filters = 0; +#ifdef LODEPNG_COMPILE_ANCILLARY_CHUNKS + settings->add_id = 0; + settings->text_compression = 1; +#endif /*LODEPNG_COMPILE_ANCILLARY_CHUNKS*/ +} + +#endif /*LODEPNG_COMPILE_ENCODER*/ +#endif /*LODEPNG_COMPILE_PNG*/ + +#ifdef LODEPNG_COMPILE_ERROR_TEXT +/* +This returns the description of a numerical error code in English. This is also +the documentation of all the error codes. +*/ +const char* lodepng_error_text(unsigned code) +{ + switch(code) + { + case 0: return "no error, everything went ok"; + case 1: return "nothing done yet"; /*the Encoder/Decoder has done nothing yet, error checking makes no sense yet*/ + case 10: return "end of input memory reached without huffman end code"; /*while huffman decoding*/ + case 11: return "error in code tree made it jump outside of huffman tree"; /*while huffman decoding*/ + case 13: return "problem while processing dynamic deflate block"; + case 14: return "problem while processing dynamic deflate block"; + case 15: return "problem while processing dynamic deflate block"; + case 16: return "unexisting code while processing dynamic deflate block"; + case 17: return "end of out buffer memory reached while inflating"; + case 18: return "invalid distance code while inflating"; + case 19: return "end of out buffer memory reached while inflating"; + case 20: return "invalid deflate block BTYPE encountered while decoding"; + case 21: return "NLEN is not ones complement of LEN in a deflate block"; + + /*end of out buffer memory reached while inflating: + This can happen if the inflated deflate data is longer than the amount of bytes required to fill up + all the pixels of the image, given the color depth and image dimensions. Something that doesn't + happen in a normal, well encoded, PNG image.*/ + case 22: return "end of out buffer memory reached while inflating"; + + case 23: return "end of in buffer memory reached while inflating"; + case 24: return "invalid FCHECK in zlib header"; + case 25: return "invalid compression method in zlib header"; + case 26: return "FDICT encountered in zlib header while it's not used for PNG"; + case 27: return "PNG file is smaller than a PNG header"; + /*Checks the magic file header, the first 8 bytes of the PNG file*/ + case 28: return "incorrect PNG signature, it's no PNG or corrupted"; + case 29: return "first chunk is not the header chunk"; + case 30: return "chunk length too large, chunk broken off at end of file"; + case 31: return "illegal PNG color type or bpp"; + case 32: return "illegal PNG compression method"; + case 33: return "illegal PNG filter method"; + case 34: return "illegal PNG interlace method"; + case 35: return "chunk length of a chunk is too large or the chunk too small"; + case 36: return "illegal PNG filter type encountered"; + case 37: return "illegal bit depth for this color type given"; + case 38: return "the palette is too big"; /*more than 256 colors*/ + case 39: return "more palette alpha values given in tRNS chunk than there are colors in the palette"; + case 40: return "tRNS chunk has wrong size for greyscale image"; + case 41: return "tRNS chunk has wrong size for RGB image"; + case 42: return "tRNS chunk appeared while it was not allowed for this color type"; + case 43: return "bKGD chunk has wrong size for palette image"; + case 44: return "bKGD chunk has wrong size for greyscale image"; + case 45: return "bKGD chunk has wrong size for RGB image"; + /*Is the palette too small?*/ + case 46: return "a value in indexed image is larger than the palette size (bitdepth = 8)"; + /*Is the palette too small?*/ + case 47: return "a value in indexed image is larger than the palette size (bitdepth < 8)"; + /*the input data is empty, maybe a PNG file doesn't exist or is in the wrong path*/ + case 48: return "empty input or file doesn't exist"; + case 49: return "jumped past memory while generating dynamic huffman tree"; + case 50: return "jumped past memory while generating dynamic huffman tree"; + case 51: return "jumped past memory while inflating huffman block"; + case 52: return "jumped past memory while inflating"; + case 53: return "size of zlib data too small"; + case 54: return "repeat symbol in tree while there was no value symbol yet"; + + /*jumped past tree while generating huffman tree, this could be when the + tree will have more leaves than symbols after generating it out of the + given lenghts. They call this an oversubscribed dynamic bit lengths tree in zlib.*/ + case 55: return "jumped past tree while generating huffman tree"; + + case 56: return "given output image colortype or bitdepth not supported for color conversion"; + case 57: return "invalid CRC encountered (checking CRC can be disabled)"; + case 58: return "invalid ADLER32 encountered (checking ADLER32 can be disabled)"; + case 59: return "requested color conversion not supported"; + case 60: return "invalid window size given in the settings of the encoder (must be 0-32768)"; + case 61: return "invalid BTYPE given in the settings of the encoder (only 0, 1 and 2 are allowed)"; + /*LodePNG leaves the choice of RGB to greyscale conversion formula to the user.*/ + case 62: return "conversion from color to greyscale not supported"; + case 63: return "length of a chunk too long, max allowed for PNG is 2147483647 bytes per chunk"; /*(2^31-1)*/ + /*this would result in the inability of a deflated block to ever contain an end code. It must be at least 1.*/ + case 64: return "the length of the END symbol 256 in the Huffman tree is 0"; + case 66: return "the length of a text chunk keyword given to the encoder is longer than the maximum of 79 bytes"; + case 67: return "the length of a text chunk keyword given to the encoder is smaller than the minimum of 1 byte"; + case 68: return "tried to encode a PLTE chunk with a palette that has less than 1 or more than 256 colors"; + case 69: return "unknown chunk type with 'critical' flag encountered by the decoder"; + case 71: return "unexisting interlace mode given to encoder (must be 0 or 1)"; + case 72: return "while decoding, unexisting compression method encountering in zTXt or iTXt chunk (it must be 0)"; + case 73: return "invalid tIME chunk size"; + case 74: return "invalid pHYs chunk size"; + /*length could be wrong, or data chopped off*/ + case 75: return "no null termination char found while decoding text chunk"; + case 76: return "iTXt chunk too short to contain required bytes"; + case 77: return "integer overflow in buffer size"; + case 78: return "failed to open file for reading"; /*file doesn't exist or couldn't be opened for reading*/ + case 79: return "failed to open file for writing"; + case 80: return "tried creating a tree of 0 symbols"; + case 81: return "lazy matching at pos 0 is impossible"; + case 82: return "color conversion to palette requested while a color isn't in palette"; + case 83: return "memory allocation failed"; + case 84: return "given image too small to contain all pixels to be encoded"; + case 85: return "internal color conversion bug"; + case 86: return "impossible offset in lz77 encoding (internal bug)"; + } + return "unknown error code"; +} +#endif /*LODEPNG_COMPILE_ERROR_TEXT*/ + +/* ////////////////////////////////////////////////////////////////////////// */ +/* ////////////////////////////////////////////////////////////////////////// */ +/* // C++ Wrapper // */ +/* ////////////////////////////////////////////////////////////////////////// */ +/* ////////////////////////////////////////////////////////////////////////// */ + + +#ifdef LODEPNG_COMPILE_CPP +namespace lodepng +{ + +#ifdef LODEPNG_COMPILE_DISK +void load_file(std::vector& buffer, const std::string& filename) +{ + std::ifstream file(filename.c_str(), std::ios::in|std::ios::binary|std::ios::ate); + + /*get filesize*/ + std::streamsize size = 0; + if(file.seekg(0, std::ios::end).good()) size = file.tellg(); + if(file.seekg(0, std::ios::beg).good()) size -= file.tellg(); + + /*read contents of the file into the vector*/ + buffer.resize(size_t(size)); + if(size > 0) file.read((char*)(&buffer[0]), size); +} + +/*write given buffer to the file, overwriting the file, it doesn't append to it.*/ +void save_file(const std::vector& buffer, const std::string& filename) +{ + std::ofstream file(filename.c_str(), std::ios::out|std::ios::binary); + file.write(buffer.empty() ? 0 : (char*)&buffer[0], std::streamsize(buffer.size())); +} +#endif //LODEPNG_COMPILE_DISK + +#ifdef LODEPNG_COMPILE_ZLIB +#ifdef LODEPNG_COMPILE_DECODER +unsigned decompress(std::vector& out, const unsigned char* in, size_t insize, + const LodePNGDecompressSettings& settings) +{ + unsigned char* buffer = 0; + size_t buffersize = 0; + unsigned error = lodepng_zlib_decompress(&buffer, &buffersize, in, insize, &settings); + if(buffer) + { + out.insert(out.end(), &buffer[0], &buffer[buffersize]); + myfree(buffer); + } + return error; +} + +unsigned decompress(std::vector& out, const std::vector& in, + const LodePNGDecompressSettings& settings) +{ + return decompress(out, in.empty() ? 0 : &in[0], in.size(), settings); +} +#endif //LODEPNG_COMPILE_DECODER + +#ifdef LODEPNG_COMPILE_ENCODER +unsigned compress(std::vector& out, const unsigned char* in, size_t insize, + const LodePNGCompressSettings& settings) +{ + unsigned char* buffer = 0; + size_t buffersize = 0; + unsigned error = lodepng_zlib_compress(&buffer, &buffersize, in, insize, &settings); + if(buffer) + { + out.insert(out.end(), &buffer[0], &buffer[buffersize]); + myfree(buffer); + } + return error; +} + +unsigned compress(std::vector& out, const std::vector& in, + const LodePNGCompressSettings& settings) +{ + return compress(out, in.empty() ? 0 : &in[0], in.size(), settings); +} +#endif //LODEPNG_COMPILE_ENCODER +#endif //LODEPNG_COMPILE_ZLIB + + +#ifdef LODEPNG_COMPILE_PNG + +State::State() +{ + lodepng_state_init(this); +} + +State::State(const State& other) +{ + lodepng_state_init(this); + lodepng_state_copy(this, &other); +} + +State::~State() +{ + lodepng_state_cleanup(this); +} + +State& State::operator=(const State& other) +{ + lodepng_state_copy(this, &other); + return *this; +} + +#ifdef LODEPNG_COMPILE_DECODER + +unsigned decode(std::vector& out, unsigned& w, unsigned& h, const unsigned char* in, + size_t insize, LodePNGColorType colortype, unsigned bitdepth) +{ + unsigned char* buffer; + unsigned error = lodepng_decode_memory(&buffer, &w, &h, in, insize, colortype, bitdepth); + if(buffer && !error) + { + State state; + state.info_raw.colortype = colortype; + state.info_raw.bitdepth = bitdepth; + size_t buffersize = lodepng_get_raw_size(w, h, &state.info_raw); + out.insert(out.end(), &buffer[0], &buffer[buffersize]); + myfree(buffer); + } + return error; +} + +unsigned decode(std::vector& out, unsigned& w, unsigned& h, + const std::vector& in, LodePNGColorType colortype, unsigned bitdepth) +{ + return decode(out, w, h, in.empty() ? 0 : &in[0], (unsigned)in.size(), colortype, bitdepth); +} + +unsigned decode(std::vector& out, unsigned& w, unsigned& h, + State& state, + const unsigned char* in, size_t insize) +{ + unsigned char* buffer; + unsigned error = lodepng_decode(&buffer, &w, &h, &state, in, insize); + if(buffer && !error) + { + size_t buffersize = lodepng_get_raw_size(w, h, &state.info_raw); + out.insert(out.end(), &buffer[0], &buffer[buffersize]); + myfree(buffer); + } + return error; +} + +unsigned decode(std::vector& out, unsigned& w, unsigned& h, + State& state, + const std::vector& in) +{ + return decode(out, w, h, state, in.empty() ? 0 : &in[0], in.size()); +} + +#ifdef LODEPNG_COMPILE_DISK +unsigned decode(std::vector& out, unsigned& w, unsigned& h, const std::string& filename, + LodePNGColorType colortype, unsigned bitdepth) +{ + std::vector buffer; + load_file(buffer, filename); + return decode(out, w, h, buffer, colortype, bitdepth); +} +#endif //LODEPNG_COMPILE_DECODER +#endif //LODEPNG_COMPILE_DISK + +#ifdef LODEPNG_COMPILE_ENCODER +unsigned encode(std::vector& out, const unsigned char* in, unsigned w, unsigned h, + LodePNGColorType colortype, unsigned bitdepth) +{ + unsigned char* buffer; + size_t buffersize; + unsigned error = lodepng_encode_memory(&buffer, &buffersize, in, w, h, colortype, bitdepth); + if(buffer) + { + out.insert(out.end(), &buffer[0], &buffer[buffersize]); + myfree(buffer); + } + return error; +} + +unsigned encode(std::vector& out, + const std::vector& in, unsigned w, unsigned h, + LodePNGColorType colortype, unsigned bitdepth) +{ + if(lodepng_get_raw_size_lct(w, h, colortype, bitdepth) > in.size()) return 84; + return encode(out, in.empty() ? 0 : &in[0], w, h, colortype, bitdepth); +} + +unsigned encode(std::vector& out, + const unsigned char* in, unsigned w, unsigned h, + State& state) +{ + unsigned char* buffer; + size_t buffersize; + unsigned error = lodepng_encode(&buffer, &buffersize, in, w, h, &state); + if(buffer) + { + out.insert(out.end(), &buffer[0], &buffer[buffersize]); + myfree(buffer); + } + return error; +} + +unsigned encode(std::vector& out, + const std::vector& in, unsigned w, unsigned h, + State& state) +{ + if(lodepng_get_raw_size(w, h, &state.info_raw) > in.size()) return 84; + return encode(out, in.empty() ? 0 : &in[0], w, h, state); +} + +#ifdef LODEPNG_COMPILE_DISK +unsigned encode(const std::string& filename, + const unsigned char* in, unsigned w, unsigned h, + LodePNGColorType colortype, unsigned bitdepth) +{ + std::vector buffer; + unsigned error = encode(buffer, in, w, h, colortype, bitdepth); + if(!error) save_file(buffer, filename); + return error; +} + +unsigned encode(const std::string& filename, + const std::vector& in, unsigned w, unsigned h, + LodePNGColorType colortype, unsigned bitdepth) +{ + if(lodepng_get_raw_size_lct(w, h, colortype, bitdepth) > in.size()) return 84; + return encode(filename, in.empty() ? 0 : &in[0], w, h, colortype, bitdepth); +} +#endif //LODEPNG_COMPILE_DISK +#endif //LODEPNG_COMPILE_ENCODER +#endif //LODEPNG_COMPILE_PNG +} //namespace lodepng +#endif /*LODEPNG_COMPILE_CPP*/ diff --git a/lib/gui/lodepng.h b/lib/gui/lodepng.h new file mode 100644 index 0000000..50d5303 --- /dev/null +++ b/lib/gui/lodepng.h @@ -0,0 +1,1640 @@ +/* +LodePNG version 20120729 + +Copyright (c) 2005-2012 Lode Vandevenne + +This software is provided 'as-is', without any express or implied +warranty. In no event will the authors be held liable for any damages +arising from the use of this software. + +Permission is granted to anyone to use this software for any purpose, +including commercial applications, and to alter it and redistribute it +freely, subject to the following restrictions: + + 1. The origin of this software must not be misrepresented; you must not + claim that you wrote the original software. If you use this software + in a product, an acknowledgment in the product documentation would be + appreciated but is not required. + + 2. Altered source versions must be plainly marked as such, and must not be + misrepresented as being the original software. + + 3. This notice may not be removed or altered from any source + distribution. +*/ + +#ifndef LODEPNG_H +#define LODEPNG_H + +#define LODEPNG_NO_COMPILE_ENCODER +#define LODEPNG_NO_COMPILE_ANCILLARY_CHUNKS +#define LODEPNG_NO_COMPILE_CPP +#define LODEPNG_NO_COMPILE_DISK +#define LODEPNG_NO_COMPILE_ZLIB +#define LODEPNG_NO_COMPILE_CPP + +#include /*for size_t*/ + +#ifdef __cplusplus +#include +#include +#endif /*__cplusplus*/ + +/* +The following #defines are used to create code sections. They can be disabled +to disable code sections, which can give faster compile time and smaller binary. +The "NO_COMPILE" defines are designed to be used to pass as defines to the +compiler command to disable them without modifying this header, e.g. +-DLODEPNG_NO_COMPILE_ZLIB for gcc. +*/ +/*deflate&zlib. If disabled, you need to define two zlib functions, see documtation of LODEPNG_CUSTOM_ZLIB_... below*/ +#ifndef LODEPNG_NO_COMPILE_ZLIB +#define LODEPNG_COMPILE_ZLIB +#endif +/*png encoder and png decoder*/ +#ifndef LODEPNG_NO_COMPILE_PNG +#define LODEPNG_COMPILE_PNG +#endif +/*deflate&zlib decoder and png decoder*/ +#ifndef LODEPNG_NO_COMPILE_DECODER +#define LODEPNG_COMPILE_DECODER +#endif +/*deflate&zlib encoder and png encoder*/ +#ifndef LODEPNG_NO_COMPILE_ENCODER +#define LODEPNG_COMPILE_ENCODER +#endif +/*the optional built in harddisk file loading and saving functions*/ +#ifndef LODEPNG_NO_COMPILE_DISK +#define LODEPNG_COMPILE_DISK +#endif +/*support for chunks other than IHDR, IDAT, PLTE, tRNS, IEND: ancillary and unknown chunks*/ +#ifndef LODEPNG_NO_COMPILE_ANCILLARY_CHUNKS +#define LODEPNG_COMPILE_ANCILLARY_CHUNKS +#endif +/*ability to convert error numerical codes to English text string*/ +#ifndef LODEPNG_NO_COMPILE_ERROR_TEXT +#define LODEPNG_COMPILE_ERROR_TEXT +#endif +/*compile the C++ version (you can disable the C++ wrapper here even when compiling for C++)*/ +#ifdef __cplusplus +#ifndef LODEPNG_NO_COMPILE_CPP +#define LODEPNG_COMPILE_CPP +#endif +#endif + +/* +custom zlib decoder (if LODEPNG_COMPILE_ZLIB is disabled, this is ignored, always treated as "1"): +0: not custom, use LodePNG's zlib decoder +1: allow using custom zlib decoder with a setting +--> you must then provide following function in your source files that LodePNG will link to: + unsigned lodepng_custom_inflate(unsigned char**, size_t*, const unsigned char*, size_t, + const LodePNGDecompressSettings*) +2: allow using custom deflate decoder with a setting +--> you must then provide following function in your source files that LodePNG will link to: + unsigned lodepng_custom_zlib_decompress(unsigned char**, size_t*, const unsigned char*, size_t, + const LodePNGDecompressSettings*) +*/ +#ifndef LODEPNG_OVERRIDE_CUSTOM_ZLIB_DECODER +#define LODEPNG_CUSTOM_ZLIB_DECODER 0 +#else +#define LODEPNG_CUSTOM_ZLIB_DECODER LODEPNG_OVERRIDE_CUSTOM_ZLIB_DECODER +#endif + +/* +custom zlib encoder (if LODEPNG_COMPILE_ZLIB is disabled, this is ignored, always treated as "1"): +0: not custom, use LodePNG's zlib encoder +1: allow using custom zlib encoder with a setting +--> you must then provide following function in your source files that LodePNG will link to: + unsigned lodepng_custom_deflate(unsigned char**, size_t*, const unsigned char*, size_t, + const LodePNGCompressSettings*) +2: allow using custom deflate encoder with a setting +--> you must then provide following function in your source files that LodePNG will link to: + unsigned lodepng_custom_zlib_compress(unsigned char**, size_t*, const unsigned char*, size_t, + const LodePNGCompressSettings*) +*/ +#ifndef LODEPNG_OVERRIDE_CUSTOM_ZLIB_ENCODER +#define LODEPNG_CUSTOM_ZLIB_ENCODER 0 +#else +#define LODEPNG_CUSTOM_ZLIB_ENCODER LODEPNG_OVERRIDE_CUSTOM_ZLIB_ENCODER +#endif + +#ifdef LODEPNG_COMPILE_PNG +/*The PNG color types (also used for raw).*/ +typedef enum LodePNGColorType +{ + LCT_GREY = 0, /*greyscale: 1,2,4,8,16 bit*/ + LCT_RGB = 2, /*RGB: 8,16 bit*/ + LCT_PALETTE = 3, /*palette: 1,2,4,8 bit*/ + LCT_GREY_ALPHA = 4, /*greyscale with alpha: 8,16 bit*/ + LCT_RGBA = 6 /*RGB with alpha: 8,16 bit*/ +} LodePNGColorType; + +#ifdef LODEPNG_COMPILE_DECODER +/* +Converts PNG data in memory to raw pixel data. +out: Output parameter. Pointer to buffer that will contain the raw pixel data. + After decoding, its size is w * h * (bytes per pixel) bytes larger than + initially. Bytes per pixel depends on colortype and bitdepth. + Must be freed after usage with free(*out). +w: Output parameter. Pointer to width of pixel data. +h: Output parameter. Pointer to height of pixel data. +in: Memory buffer with the PNG file. +insize: size of the in buffer. +colortype: the desired color type for the raw output image. See explanation on PNG color types. +bitdepth: the desired bit depth for the raw output image. See explanation on PNG color types. +Return value: LodePNG error code (0 means no error). +*/ +unsigned lodepng_decode_memory(unsigned char** out, unsigned* w, unsigned* h, + const unsigned char* in, size_t insize, + LodePNGColorType colortype, unsigned bitdepth); + +/*Same as lodepng_decode_memory, but always decodes to 32-bit RGBA raw image*/ +unsigned lodepng_decode32(unsigned char** out, unsigned* w, unsigned* h, + const unsigned char* in, size_t insize); + +/*Same as lodepng_decode_memory, but always decodes to 24-bit RGB raw image*/ +unsigned lodepng_decode24(unsigned char** out, unsigned* w, unsigned* h, + const unsigned char* in, size_t insize); + +#ifdef LODEPNG_COMPILE_DISK +/* +Load PNG from disk, from file with given name. +Same as the other decode functions, but instead takes a filename as input. +*/ +unsigned lodepng_decode_file(unsigned char** out, unsigned* w, unsigned* h, + const char* filename, + LodePNGColorType colortype, unsigned bitdepth); + +/*Same as lodepng_decode_file, but always decodes to 32-bit RGBA raw image.*/ +unsigned lodepng_decode32_file(unsigned char** out, unsigned* w, unsigned* h, + const char* filename); + +/*Same as lodepng_decode_file, but always decodes to 24-bit RGB raw image.*/ +unsigned lodepng_decode24_file(unsigned char** out, unsigned* w, unsigned* h, + const char* filename); +#endif /*LODEPNG_COMPILE_DISK*/ +#endif /*LODEPNG_COMPILE_DECODER*/ + + +#ifdef LODEPNG_COMPILE_ENCODER +/* +Converts raw pixel data into a PNG image in memory. The colortype and bitdepth + of the output PNG image cannot be chosen, they are automatically determined + by the colortype, bitdepth and content of the input pixel data. +out: Output parameter. Pointer to buffer that will contain the raw pixel data. + Must be freed after usage with free(*out). +outsize: Output parameter. Pointer to the size in bytes of the out buffer. +image: The raw pixel data to encode. The size of this buffer should be + w * h * (bytes per pixel), bytes per pixel depends on colortype and bitdepth. +w: width of the raw pixel data in pixels. +h: height of the raw pixel data in pixels. +colortype: the color type of the raw input image. See explanation on PNG color types. +bitdepth: the bit depth of the raw input image. See explanation on PNG color types. +Return value: LodePNG error code (0 means no error). +*/ +unsigned lodepng_encode_memory(unsigned char** out, size_t* outsize, + const unsigned char* image, unsigned w, unsigned h, + LodePNGColorType colortype, unsigned bitdepth); + +/*Same as lodepng_encode_memory, but always encodes from 32-bit RGBA raw image.*/ +unsigned lodepng_encode32(unsigned char** out, size_t* outsize, + const unsigned char* image, unsigned w, unsigned h); + +/*Same as lodepng_encode_memory, but always encodes from 24-bit RGB raw image.*/ +unsigned lodepng_encode24(unsigned char** out, size_t* outsize, + const unsigned char* image, unsigned w, unsigned h); + +#ifdef LODEPNG_COMPILE_DISK +/* +Converts raw pixel data into a PNG file on disk. +Same as the other encode functions, but instead takes a filename as output. +NOTE: This overwrites existing files without warning! +*/ +unsigned lodepng_encode_file(const char* filename, + const unsigned char* image, unsigned w, unsigned h, + LodePNGColorType colortype, unsigned bitdepth); + +/*Same as lodepng_encode_file, but always encodes from 32-bit RGBA raw image.*/ +unsigned lodepng_encode32_file(const char* filename, + const unsigned char* image, unsigned w, unsigned h); + +/*Same as lodepng_encode_file, but always encodes from 24-bit RGB raw image.*/ +unsigned lodepng_encode24_file(const char* filename, + const unsigned char* image, unsigned w, unsigned h); +#endif /*LODEPNG_COMPILE_DISK*/ +#endif /*LODEPNG_COMPILE_ENCODER*/ + + +#ifdef LODEPNG_COMPILE_CPP +namespace lodepng +{ +#ifdef LODEPNG_COMPILE_DECODER +/*Same as lodepng_decode_memory, but decodes to an std::vector.*/ +unsigned decode(std::vector& out, unsigned& w, unsigned& h, + const unsigned char* in, size_t insize, + LodePNGColorType colortype = LCT_RGBA, unsigned bitdepth = 8); +unsigned decode(std::vector& out, unsigned& w, unsigned& h, + const std::vector& in, + LodePNGColorType colortype = LCT_RGBA, unsigned bitdepth = 8); +#ifdef LODEPNG_COMPILE_DISK +/* +Converts PNG file from disk to raw pixel data in memory. +Same as the other decode functions, but instead takes a filename as input. +*/ +unsigned decode(std::vector& out, unsigned& w, unsigned& h, + const std::string& filename, + LodePNGColorType colortype = LCT_RGBA, unsigned bitdepth = 8); +#endif //LODEPNG_COMPILE_DISK +#endif //LODEPNG_COMPILE_DECODER + +#ifdef LODEPNG_COMPILE_ENCODER +/*Same as lodepng_encode_memory, but encodes to an std::vector.*/ +unsigned encode(std::vector& out, + const unsigned char* in, unsigned w, unsigned h, + LodePNGColorType colortype = LCT_RGBA, unsigned bitdepth = 8); +unsigned encode(std::vector& out, + const std::vector& in, unsigned w, unsigned h, + LodePNGColorType colortype = LCT_RGBA, unsigned bitdepth = 8); +#ifdef LODEPNG_COMPILE_DISK +/* +Converts 32-bit RGBA raw pixel data into a PNG file on disk. +Same as the other encode functions, but instead takes a filename as output. +NOTE: This overwrites existing files without warning! +*/ +unsigned encode(const std::string& filename, + const unsigned char* in, unsigned w, unsigned h, + LodePNGColorType colortype = LCT_RGBA, unsigned bitdepth = 8); +unsigned encode(const std::string& filename, + const std::vector& in, unsigned w, unsigned h, + LodePNGColorType colortype = LCT_RGBA, unsigned bitdepth = 8); +#endif //LODEPNG_COMPILE_DISK +#endif //LODEPNG_COMPILE_ENCODER +} //namespace lodepng +#endif /*LODEPNG_COMPILE_CPP*/ +#endif /*LODEPNG_COMPILE_PNG*/ + +#ifdef LODEPNG_COMPILE_ERROR_TEXT +/*Returns an English description of the numerical error code.*/ +const char* lodepng_error_text(unsigned code); +#endif /*LODEPNG_COMPILE_ERROR_TEXT*/ + +#ifdef LODEPNG_COMPILE_DECODER +/*Settings for zlib decompression*/ +typedef struct LodePNGDecompressSettings +{ + unsigned ignore_adler32; /*if 1, continue and don't give an error message if the Adler32 checksum is corrupted*/ + unsigned custom_decoder; /*use custom decoder if LODEPNG_CUSTOM_ZLIB_DECODER and LODEPNG_COMPILE_ZLIB are enabled*/ +} LodePNGDecompressSettings; + +extern const LodePNGDecompressSettings lodepng_default_decompress_settings; +void lodepng_decompress_settings_init(LodePNGDecompressSettings* settings); +#endif /*LODEPNG_COMPILE_DECODER*/ + +/* +Settings for zlib compression. Tweaking these settings tweaks the balance +between speed and compression ratio. +*/ +typedef struct LodePNGCompressSettings /*deflate = compress*/ +{ + /*LZ77 related settings*/ + unsigned btype; /*the block type for LZ (0, 1, 2 or 3, see zlib standard). Should be 2 for proper compression.*/ + unsigned use_lz77; /*whether or not to use LZ77. Should be 1 for proper compression.*/ + unsigned windowsize; /*the maximum is 32768, higher gives more compression but is slower. Typical value: 2048.*/ + unsigned custom_encoder; /*use custom encoder if LODEPNG_CUSTOM_ZLIB_DECODER and LODEPNG_COMPILE_ZLIB are enabled*/ +} LodePNGCompressSettings; + +#ifdef LODEPNG_COMPILE_ENCODER +extern const LodePNGCompressSettings lodepng_default_compress_settings; +void lodepng_compress_settings_init(LodePNGCompressSettings* settings); +#endif /*LODEPNG_COMPILE_ENCODER*/ + +#ifdef LODEPNG_COMPILE_PNG +/* +Color mode of an image. Contains all information required to decode the pixel +bits to RGBA colors. This information is the same as used in the PNG file +format, and is used both for PNG and raw image data in LodePNG. +*/ +typedef struct LodePNGColorMode +{ + /*header (IHDR)*/ + LodePNGColorType colortype; /*color type, see PNG standard or documentation further in this header file*/ + unsigned bitdepth; /*bits per sample, see PNG standard or documentation further in this header file*/ + + /* + palette (PLTE and tRNS) + + Dynamically allocated with the colors of the palette, including alpha. + When encoding a PNG, to store your colors in the palette of the LodePNGColorMode, first use + lodepng_palette_clear, then for each color use lodepng_palette_add. + If you encode an image without alpha with palette, don't forget to put value 255 in each A byte of the palette. + + When decoding, by default you can ignore this palette, since LodePNG already + fills the palette colors in the pixels of the raw RGBA output. + + The palette is only supported for color type 3. + */ + unsigned char* palette; /*palette in RGBARGBA... order*/ + size_t palettesize; /*palette size in number of colors (amount of bytes is 4 * palettesize)*/ + + /* + transparent color key (tRNS) + + This color uses the same bit depth as the bitdepth value in this struct, which can be 1-bit to 16-bit. + For greyscale PNGs, r, g and b will all 3 be set to the same. + + When decoding, by default you can ignore this information, since LodePNG sets + pixels with this key to transparent already in the raw RGBA output. + + The color key is only supported for color types 0 and 2. + */ + unsigned key_defined; /*is a transparent color key given? 0 = false, 1 = true*/ + unsigned key_r; /*red/greyscale component of color key*/ + unsigned key_g; /*green component of color key*/ + unsigned key_b; /*blue component of color key*/ +} LodePNGColorMode; + +/*init, cleanup and copy functions to use with this struct*/ +void lodepng_color_mode_init(LodePNGColorMode* info); +void lodepng_color_mode_cleanup(LodePNGColorMode* info); +/*return value is error code (0 means no error)*/ +unsigned lodepng_color_mode_copy(LodePNGColorMode* dest, const LodePNGColorMode* source); + +void lodepng_palette_clear(LodePNGColorMode* info); +/*add 1 color to the palette*/ +unsigned lodepng_palette_add(LodePNGColorMode* info, + unsigned char r, unsigned char g, unsigned char b, unsigned char a); + +/*get the total amount of bits per pixel, based on colortype and bitdepth in the struct*/ +unsigned lodepng_get_bpp(const LodePNGColorMode* info); +/*get the amount of color channels used, based on colortype in the struct. +If a palette is used, it counts as 1 channel.*/ +unsigned lodepng_get_channels(const LodePNGColorMode* info); +/*is it a greyscale type? (only colortype 0 or 4)*/ +unsigned lodepng_is_greyscale_type(const LodePNGColorMode* info); +/*has it got an alpha channel? (only colortype 2 or 6)*/ +unsigned lodepng_is_alpha_type(const LodePNGColorMode* info); +/*has it got a palette? (only colortype 3)*/ +unsigned lodepng_is_palette_type(const LodePNGColorMode* info); +/*only returns true if there is a palette and there is a value in the palette with alpha < 255. +Loops through the palette to check this.*/ +unsigned lodepng_has_palette_alpha(const LodePNGColorMode* info); +/* +Check if the given color info indicates the possibility of having non-opaque pixels in the PNG image. +Returns true if the image can have translucent or invisible pixels (it still be opaque if it doesn't use such pixels). +Returns false if the image can only have opaque pixels. +In detail, it returns true only if it's a color type with alpha, or has a palette with non-opaque values, +or if "key_defined" is true. +*/ +unsigned lodepng_can_have_alpha(const LodePNGColorMode* info); +/*Returns the byte size of a raw image buffer with given width, height and color mode*/ +size_t lodepng_get_raw_size(unsigned w, unsigned h, const LodePNGColorMode* color); + +#ifdef LODEPNG_COMPILE_ANCILLARY_CHUNKS +/*The information of a Time chunk in PNG.*/ +typedef struct LodePNGTime +{ + unsigned year; /*2 bytes used (0-65535)*/ + unsigned month; /*1-12*/ + unsigned day; /*1-31*/ + unsigned hour; /*0-23*/ + unsigned minute; /*0-59*/ + unsigned second; /*0-60 (to allow for leap seconds)*/ +} LodePNGTime; +#endif /*LODEPNG_COMPILE_ANCILLARY_CHUNKS*/ + +/*Information about the PNG image, except pixels, width and height.*/ +typedef struct LodePNGInfo +{ + /*header (IHDR), palette (PLTE) and transparency (tRNS) chunks*/ + unsigned compression_method;/*compression method of the original file. Always 0.*/ + unsigned filter_method; /*filter method of the original file*/ + unsigned interlace_method; /*interlace method of the original file*/ + LodePNGColorMode color; /*color type and bits, palette and transparency of the PNG file*/ + +#ifdef LODEPNG_COMPILE_ANCILLARY_CHUNKS + /* + suggested background color chunk (bKGD) + This color uses the same color mode as the PNG (except alpha channel), which can be 1-bit to 16-bit. + + For greyscale PNGs, r, g and b will all 3 be set to the same. When encoding + the encoder writes the red one. For palette PNGs: When decoding, the RGB value + will be stored, not a palette index. But when encoding, specify the index of + the palette in background_r, the other two are then ignored. + + The decoder does not use this background color to edit the color of pixels. + */ + unsigned background_defined; /*is a suggested background color given?*/ + unsigned background_r; /*red component of suggested background color*/ + unsigned background_g; /*green component of suggested background color*/ + unsigned background_b; /*blue component of suggested background color*/ + + /* + non-international text chunks (tEXt and zTXt) + + The char** arrays each contain num strings. The actual messages are in + text_strings, while text_keys are keywords that give a short description what + the actual text represents, e.g. Title, Author, Description, or anything else. + + A keyword is minimum 1 character and maximum 79 characters long. It's + discouraged to use a single line length longer than 79 characters for texts. + + Don't allocate these text buffers yourself. Use the init/cleanup functions + correctly and use lodepng_add_text and lodepng_clear_text. + */ + size_t text_num; /*the amount of texts in these char** buffers (there may be more texts in itext)*/ + char** text_keys; /*the keyword of a text chunk (e.g. "Comment")*/ + char** text_strings; /*the actual text*/ + + /* + international text chunks (iTXt) + Similar to the non-international text chunks, but with additional strings + "langtags" and "transkeys". + */ + size_t itext_num; /*the amount of international texts in this PNG*/ + char** itext_keys; /*the English keyword of the text chunk (e.g. "Comment")*/ + char** itext_langtags; /*language tag for this text's language, ISO/IEC 646 string, e.g. ISO 639 language tag*/ + char** itext_transkeys; /*keyword translated to the international language - UTF-8 string*/ + char** itext_strings; /*the actual international text - UTF-8 string*/ + + /*time chunk (tIME)*/ + unsigned time_defined; /*set to 1 to make the encoder generate a tIME chunk*/ + LodePNGTime time; + + /*phys chunk (pHYs)*/ + unsigned phys_defined; /*if 0, there is no pHYs chunk and the values below are undefined, if 1 else there is one*/ + unsigned phys_x; /*pixels per unit in x direction*/ + unsigned phys_y; /*pixels per unit in y direction*/ + unsigned phys_unit; /*may be 0 (unknown unit) or 1 (metre)*/ + + /* + unknown chunks + There are 3 buffers, one for each position in the PNG where unknown chunks can appear + each buffer contains all unknown chunks for that position consecutively + The 3 buffers are the unknown chunks between certain critical chunks: + 0: IHDR-PLTE, 1: PLTE-IDAT, 2: IDAT-IEND + Do not allocate or traverse this data yourself. Use the chunk traversing functions declared + later, such as lodepng_chunk_next and lodepng_chunk_append, to read/write this struct. + */ + unsigned char* unknown_chunks_data[3]; + size_t unknown_chunks_size[3]; /*size in bytes of the unknown chunks, given for protection*/ +#endif /*LODEPNG_COMPILE_ANCILLARY_CHUNKS*/ +} LodePNGInfo; + +/*init, cleanup and copy functions to use with this struct*/ +void lodepng_info_init(LodePNGInfo* info); +void lodepng_info_cleanup(LodePNGInfo* info); +/*return value is error code (0 means no error)*/ +unsigned lodepng_info_copy(LodePNGInfo* dest, const LodePNGInfo* source); + +#ifdef LODEPNG_COMPILE_ANCILLARY_CHUNKS +void lodepng_clear_text(LodePNGInfo* info); /*use this to clear the texts again after you filled them in*/ +unsigned lodepng_add_text(LodePNGInfo* info, const char* key, const char* str); /*push back both texts at once*/ + +void lodepng_clear_itext(LodePNGInfo* info); /*use this to clear the itexts again after you filled them in*/ +unsigned lodepng_add_itext(LodePNGInfo* info, const char* key, const char* langtag, + const char* transkey, const char* str); /*push back the 4 texts of 1 chunk at once*/ +#endif /*LODEPNG_COMPILE_ANCILLARY_CHUNKS*/ + +/* +Converts raw buffer from one color type to another color type, based on +LodePNGColorMode structs to describe the input and output color type. +See the reference manual at the end of this header file to see which color conversions are supported. +return value = LodePNG error code (0 if all went ok, an error if the conversion isn't supported) +The out buffer must have size (w * h * bpp + 7) / 8, where bpp is the bits per pixel +of the output color type (lodepng_get_bpp) +*/ +unsigned lodepng_convert(unsigned char* out, const unsigned char* in, + LodePNGColorMode* mode_out, LodePNGColorMode* mode_in, + unsigned w, unsigned h); + + +#ifdef LODEPNG_COMPILE_DECODER +/* +Settings for the decoder. This contains settings for the PNG and the Zlib +decoder, but not the Info settings from the Info structs. +*/ +typedef struct LodePNGDecoderSettings +{ + LodePNGDecompressSettings zlibsettings; /*in here is the setting to ignore Adler32 checksums*/ + + unsigned ignore_crc; /*ignore CRC checksums*/ + unsigned color_convert; /*whether to convert the PNG to the color type you want. Default: yes*/ + +#ifdef LODEPNG_COMPILE_ANCILLARY_CHUNKS + unsigned read_text_chunks; /*if false but remember_unknown_chunks is true, they're stored in the unknown chunks*/ + /*store all bytes from unknown chunks in the LodePNGInfo (off by default, useful for a png editor)*/ + unsigned remember_unknown_chunks; +#endif /*LODEPNG_COMPILE_ANCILLARY_CHUNKS*/ +} LodePNGDecoderSettings; + +void lodepng_decoder_settings_init(LodePNGDecoderSettings* settings); +#endif /*LODEPNG_COMPILE_DECODER*/ + +#ifdef LODEPNG_COMPILE_ENCODER +/*automatically use color type with less bits per pixel if losslessly possible. Default: AUTO*/ +typedef enum LodePNGFilterStrategy +{ + LFS_HEURISTIC, /*official PNG heuristic*/ + LFS_ZERO, /*every filter at zero*/ + LFS_MINSUM, /*like the official PNG heuristic, but use minimal sum always, including palette and low bitdepth images*/ + /* + Brute-force-search PNG filters by compressing each filter for each scanline. + This gives better compression, at the cost of being super slow. Experimental! + If you enable this, also set zlibsettings.windowsize to 32768 and choose an + optimal color mode for the PNG image for best compression. Default: 0 (false). + */ + LFS_BRUTE_FORCE, + LFS_PREDEFINED /*use predefined_filters buffer: you specify the filter type for each scanline*/ +} LodePNGFilterStrategy; + +/*automatically use color type with less bits per pixel if losslessly possible. Default: LAC_AUTO*/ +typedef enum LodePNGAutoConvert +{ + LAC_NO, /*use color type user requested*/ + LAC_ALPHA, /*use color type user requested, but if only opaque pixels and RGBA or grey+alpha, use RGB or grey*/ + LAC_AUTO, /*use PNG color type that can losslessly represent the uncompressed image the smallest possible*/ + /* + like AUTO, but do not choose 1, 2 or 4 bit per pixel types. + sometimes a PNG image compresses worse if less than 8 bits per pixels. + */ + LAC_AUTO_NO_NIBBLES +} LodePNGAutoConvert; + + +/*Settings for the encoder.*/ +typedef struct LodePNGEncoderSettings +{ + LodePNGCompressSettings zlibsettings; /*settings for the zlib encoder, such as window size, ...*/ + + LodePNGAutoConvert auto_convert; /*how to automatically choose output PNG color type, if at all*/ + + LodePNGFilterStrategy filter_strategy; + + /*used if filter_strategy is LFS_PREDEFINED. In that case, this must point to a buffer with + the same length as the amount of scanlines in the image, and each value must <= 5. You + have to cleanup this buffer, LodePNG will never free it.*/ + unsigned char* predefined_filters; + + /*force creating a PLTE chunk if colortype is 2 or 6 (= a suggested palette). + If colortype is 3, PLTE is _always_ created.*/ + unsigned force_palette; +#ifdef LODEPNG_COMPILE_ANCILLARY_CHUNKS + /*add LodePNG identifier and version as a text chunk, for debugging*/ + unsigned add_id; + /*encode text chunks as zTXt chunks instead of tEXt chunks, and use compression in iTXt chunks*/ + unsigned text_compression; +#endif /*LODEPNG_COMPILE_ANCILLARY_CHUNKS*/ +} LodePNGEncoderSettings; + +void lodepng_encoder_settings_init(LodePNGEncoderSettings* settings); +#endif /*LODEPNG_COMPILE_ENCODER*/ + + +#if defined(LODEPNG_COMPILE_DECODER) || defined(LODEPNG_COMPILE_ENCODER) +/*The settings, state and information for extended encoding and decoding.*/ +typedef struct LodePNGState +{ +#ifdef LODEPNG_COMPILE_DECODER + LodePNGDecoderSettings decoder; /*the decoding settings*/ +#endif /*LODEPNG_COMPILE_DECODER*/ +#ifdef LODEPNG_COMPILE_ENCODER + LodePNGEncoderSettings encoder; /*the encoding settings*/ +#endif /*LODEPNG_COMPILE_ENCODER*/ + LodePNGColorMode info_raw; /*specifies the format in which you would like to get the raw pixel buffer*/ + LodePNGInfo info_png; /*info of the PNG image obtained after decoding*/ + unsigned error; +#ifdef LODEPNG_COMPILE_CPP + //For the lodepng::State subclass. + virtual ~LodePNGState(){} +#endif +} LodePNGState; + +/*init, cleanup and copy functions to use with this struct*/ +void lodepng_state_init(LodePNGState* state); +void lodepng_state_cleanup(LodePNGState* state); +void lodepng_state_copy(LodePNGState* dest, const LodePNGState* source); +#endif /* defined(LODEPNG_COMPILE_DECODER) || defined(LODEPNG_COMPILE_ENCODER) */ + +#ifdef LODEPNG_COMPILE_DECODER +/* +Same as lodepng_decode_memory, but uses a LodePNGState to allow custom settings and +getting much more information about the PNG image and color mode. +*/ +unsigned lodepng_decode(unsigned char** out, unsigned* w, unsigned* h, + LodePNGState* state, + const unsigned char* in, size_t insize); + +/* +Read the PNG header, but not the actual data. This returns only the information +that is in the header chunk of the PNG, such as width, height and color type. The +information is placed in the info_png field of the LodePNGState. +*/ +unsigned lodepng_inspect(unsigned* w, unsigned* h, + LodePNGState* state, + const unsigned char* in, size_t insize); +#endif /*LODEPNG_COMPILE_DECODER*/ + + +#ifdef LODEPNG_COMPILE_ENCODER +/*This function allocates the out buffer with standard malloc and stores the size in *outsize.*/ +unsigned lodepng_encode(unsigned char** out, size_t* outsize, + const unsigned char* image, unsigned w, unsigned h, + LodePNGState* state); +#endif /*LODEPNG_COMPILE_ENCODER*/ + +/* +The lodepng_chunk functions are normally not needed, except to traverse the +unknown chunks stored in the LodePNGInfo struct, or add new ones to it. +It also allows traversing the chunks of an encoded PNG file yourself. + +PNG standard chunk naming conventions: +First byte: uppercase = critical, lowercase = ancillary +Second byte: uppercase = public, lowercase = private +Third byte: must be uppercase +Fourth byte: uppercase = unsafe to copy, lowercase = safe to copy +*/ + +/*get the length of the data of the chunk. Total chunk length has 12 bytes more.*/ +unsigned lodepng_chunk_length(const unsigned char* chunk); + +/*puts the 4-byte type in null terminated string*/ +void lodepng_chunk_type(char type[5], const unsigned char* chunk); + +/*check if the type is the given type*/ +unsigned char lodepng_chunk_type_equals(const unsigned char* chunk, const char* type); + +/*0: it's one of the critical chunk types, 1: it's an ancillary chunk (see PNG standard)*/ +unsigned char lodepng_chunk_ancillary(const unsigned char* chunk); + +/*0: public, 1: private (see PNG standard)*/ +unsigned char lodepng_chunk_private(const unsigned char* chunk); + +/*0: the chunk is unsafe to copy, 1: the chunk is safe to copy (see PNG standard)*/ +unsigned char lodepng_chunk_safetocopy(const unsigned char* chunk); + +/*get pointer to the data of the chunk, where the input points to the header of the chunk*/ +unsigned char* lodepng_chunk_data(unsigned char* chunk); +const unsigned char* lodepng_chunk_data_const(const unsigned char* chunk); + +/*returns 0 if the crc is correct, 1 if it's incorrect (0 for OK as usual!)*/ +unsigned lodepng_chunk_check_crc(const unsigned char* chunk); + +/*generates the correct CRC from the data and puts it in the last 4 bytes of the chunk*/ +void lodepng_chunk_generate_crc(unsigned char* chunk); + +/*iterate to next chunks. don't use on IEND chunk, as there is no next chunk then*/ +unsigned char* lodepng_chunk_next(unsigned char* chunk); +const unsigned char* lodepng_chunk_next_const(const unsigned char* chunk); + +/* +Appends chunk to the data in out. The given chunk should already have its chunk header. +The out variable and outlength are updated to reflect the new reallocated buffer. +Returns error code (0 if it went ok) +*/ +unsigned lodepng_chunk_append(unsigned char** out, size_t* outlength, const unsigned char* chunk); + +/* +Appends new chunk to out. The chunk to append is given by giving its length, type +and data separately. The type is a 4-letter string. +The out variable and outlength are updated to reflect the new reallocated buffer. +Returne error code (0 if it went ok) +*/ +unsigned lodepng_chunk_create(unsigned char** out, size_t* outlength, unsigned length, + const char* type, const unsigned char* data); + + +/*Calculate CRC32 of buffer*/ +unsigned lodepng_crc32(const unsigned char* buf, size_t len); +#endif /*LODEPNG_COMPILE_PNG*/ + + +#ifdef LODEPNG_COMPILE_ZLIB +/* +This zlib part can be used independently to zlib compress and decompress a +buffer. It cannot be used to create gzip files however, and it only supports the +part of zlib that is required for PNG, it does not support dictionaries. +*/ + +#ifdef LODEPNG_COMPILE_DECODER +/*Inflate a buffer. Inflate is the decompression step of deflate. Out buffer must be freed after use.*/ +unsigned lodepng_inflate(unsigned char** out, size_t* outsize, + const unsigned char* in, size_t insize, + const LodePNGDecompressSettings* settings); + +/* +Decompresses Zlib data. Reallocates the out buffer and appends the data. The +data must be according to the zlib specification. +Either, *out must be NULL and *outsize must be 0, or, *out must be a valid +buffer and *outsize its size in bytes. out must be freed by user after usage. +*/ +unsigned lodepng_zlib_decompress(unsigned char** out, size_t* outsize, + const unsigned char* in, size_t insize, + const LodePNGDecompressSettings* settings); +#endif /*LODEPNG_COMPILE_DECODER*/ + +#ifdef LODEPNG_COMPILE_ENCODER +/* +Compresses data with Zlib. Reallocates the out buffer and appends the data. +Zlib adds a small header and trailer around the deflate data. +The data is output in the format of the zlib specification. +Either, *out must be NULL and *outsize must be 0, or, *out must be a valid +buffer and *outsize its size in bytes. out must be freed by user after usage. +*/ +unsigned lodepng_zlib_compress(unsigned char** out, size_t* outsize, + const unsigned char* in, size_t insize, + const LodePNGCompressSettings* settings); + +/* +Find length-limited Huffman code for given frequencies. This function is in the +public interface only for tests, it's used internally by lodepng_deflate. +*/ +unsigned lodepng_huffman_code_lengths(unsigned* lengths, const unsigned* frequencies, + size_t numcodes, unsigned maxbitlen); + +/*Compress a buffer with deflate. See RFC 1951. Out buffer must be freed after use.*/ +unsigned lodepng_deflate(unsigned char** out, size_t* outsize, + const unsigned char* in, size_t insize, + const LodePNGCompressSettings* settings); + +#endif /*LODEPNG_COMPILE_ENCODER*/ +#endif /*LODEPNG_COMPILE_ZLIB*/ + +#ifdef LODEPNG_COMPILE_DISK +/* +Load a file from disk into buffer. The function allocates the out buffer, and +after usage you should free it. +out: output parameter, contains pointer to loaded buffer. +outsize: output parameter, size of the allocated out buffer +filename: the path to the file to load +return value: error code (0 means ok) +*/ +unsigned lodepng_load_file(unsigned char** out, size_t* outsize, const char* filename); + +/* +Save a file from buffer to disk. Warning, if it exists, this function overwrites +the file without warning! +buffer: the buffer to write +buffersize: size of the buffer to write +filename: the path to the file to save to +return value: error code (0 means ok) +*/ +unsigned lodepng_save_file(const unsigned char* buffer, size_t buffersize, const char* filename); +#endif /*LODEPNG_COMPILE_DISK*/ + +#ifdef LODEPNG_COMPILE_CPP +//The LodePNG C++ wrapper uses std::vectors instead of manually allocated memory buffers. +namespace lodepng +{ +#ifdef LODEPNG_COMPILE_PNG +class State : public LodePNGState +{ + public: + State(); + State(const State& other); + virtual ~State(); + State& operator=(const State& other); +}; + +#ifdef LODEPNG_COMPILE_DECODER +//Same as other lodepng::decode, but using a State for more settings and information. +unsigned decode(std::vector& out, unsigned& w, unsigned& h, + State& state, + const unsigned char* in, size_t insize); +unsigned decode(std::vector& out, unsigned& w, unsigned& h, + State& state, + const std::vector& in); +#endif /*LODEPNG_COMPILE_DECODER*/ + +#ifdef LODEPNG_COMPILE_ENCODER +//Same as other lodepng::encode, but using a State for more settings and information. +unsigned encode(std::vector& out, + const unsigned char* in, unsigned w, unsigned h, + State& state); +unsigned encode(std::vector& out, + const std::vector& in, unsigned w, unsigned h, + State& state); +#endif /*LODEPNG_COMPILE_ENCODER*/ + + +#ifdef LODEPNG_COMPILE_DISK +/* +Load a file from disk into an std::vector. If the vector is empty, then either +the file doesn't exist or is an empty file. +*/ +void load_file(std::vector& buffer, const std::string& filename); + +/* +Save the binary data in an std::vector to a file on disk. The file is overwritten +without warning. +*/ +void save_file(const std::vector& buffer, const std::string& filename); +#endif //LODEPNG_COMPILE_DISK +#endif //LODEPNG_COMPILE_PNG + +#ifdef LODEPNG_COMPILE_ZLIB +#ifdef LODEPNG_COMPILE_DECODER +//Zlib-decompress an unsigned char buffer +unsigned decompress(std::vector& out, const unsigned char* in, size_t insize, + const LodePNGDecompressSettings& settings = lodepng_default_decompress_settings); + +//Zlib-decompress an std::vector +unsigned decompress(std::vector& out, const std::vector& in, + const LodePNGDecompressSettings& settings = lodepng_default_decompress_settings); +#endif //LODEPNG_COMPILE_DECODER + +#ifdef LODEPNG_COMPILE_ENCODER +//Zlib-compress an unsigned char buffer +unsigned compress(std::vector& out, const unsigned char* in, size_t insize, + const LodePNGCompressSettings& settings = lodepng_default_compress_settings); + +//Zlib-compress an std::vector +unsigned compress(std::vector& out, const std::vector& in, + const LodePNGCompressSettings& settings = lodepng_default_compress_settings); +#endif //LODEPNG_COMPILE_ENCODER +#endif //LODEPNG_COMPILE_ZLIB +} //namespace lodepng +#endif /*LODEPNG_COMPILE_CPP*/ + +/* +TODO: +[.] test if there are no memory leaks or security exploits - done a lot but needs to be checked often +[.] check compatibility with vareous compilers - done but needs to be redone for every newer version +[X] converting color to 16-bit per channel types +[ ] read all public PNG chunk types (but never let the color profile and gamma ones touch RGB values) +[ ] make sure encoder generates no chunks with size > (2^31)-1 +[ ] partial decoding (stream processing) +[X] let the "isFullyOpaque" function check color keys and transparent palettes too +[X] better name for the variables "codes", "codesD", "codelengthcodes", "clcl" and "lldl" +[ ] don't stop decoding on errors like 69, 57, 58 (make warnings) +[ ] make option to choose if the raw image with non multiple of 8 bits per scanline should have padding bits or not +[ ] let the C++ wrapper catch exceptions coming from the standard library and return LodePNG error codes +*/ + +#endif /*LODEPNG_H inclusion guard*/ + +/* +LodePNG Documentation +--------------------- + +0. table of contents +-------------------- + + 1. about + 1.1. supported features + 1.2. features not supported + 2. C and C++ version + 3. security + 4. decoding + 5. encoding + 6. color conversions + 6.1. PNG color types + 6.2. color conversions + 6.3. padding bits + 7. error values + 8. chunks and PNG editing + 9. compiler support + 10. examples + 10.1. decoder C++ example + 10.2. decoder C example + 11. changes + 12. contact information + + +1. about +-------- + +PNG is a file format to store raster images losslessly with good compression, +supporting different color types and alpha channel. + +LodePNG is a PNG codec according to the Portable Network Graphics (PNG) +Specification (Second Edition) - W3C Recommendation 10 November 2003. + +The specifications used are: + +*) Portable Network Graphics (PNG) Specification (Second Edition): + http://www.w3.org/TR/2003/REC-PNG-20031110 +*) RFC 1950 ZLIB Compressed Data Format version 3.3: + http://www.gzip.org/zlib/rfc-zlib.html +*) RFC 1951 DEFLATE Compressed Data Format Specification ver 1.3: + http://www.gzip.org/zlib/rfc-deflate.html + +The most recent version of LodePNG can currently be found at +http://lodev.org/lodepng/ + +LodePNG works both in C (ISO C90) and C++, with a C++ wrapper that adds +extra functionality. + +LodePNG exists out of two files: +-lodepng.h: the header file for both C and C++ +-lodepng.c(pp): give it the name lodepng.c or lodepng.cpp (or .cc) depending on your usage + +If you want to start using LodePNG right away without reading this doc, get the +examples from the LodePNG website to see how to use it in code, or check the +smaller examples in chapter 13 here. + +LodePNG is simple but only supports the basic requirements. To achieve +simplicity, the following design choices were made: There are no dependencies +on any external library. There are functions to decode and encode a PNG with +a single function call, and extended versions of these functions taking a +LodePNGState struct allowing to specify or get more information. By default +the colors of the raw image are always RGB or RGBA, no matter what color type +the PNG file uses. To read and write files, there are simple functions to +convert the files to/from buffers in memory. + +This all makes LodePNG suitable for loading textures in games, demos and small +programs, ... It's less suitable for full fledged image editors, loading PNGs +over network (it requires all the image data to be available before decoding can +begin), life-critical systems, ... + +1.1. supported features +----------------------- + +The following features are supported by the decoder: + +*) decoding of PNGs with any color type, bit depth and interlace mode, to a 24- or 32-bit color raw image, + or the same color type as the PNG +*) encoding of PNGs, from any raw image to 24- or 32-bit color, or the same color type as the raw image +*) Adam7 interlace and deinterlace for any color type +*) loading the image from harddisk or decoding it from a buffer from other sources than harddisk +*) support for alpha channels, including RGBA color model, translucent palettes and color keying +*) zlib decompression (inflate) +*) zlib compression (deflate) +*) CRC32 and ADLER32 checksums +*) handling of unknown chunks, allowing making a PNG editor that stores custom and unknown chunks. +*) the following chunks are supported (generated/interpreted) by both encoder and decoder: + IHDR: header information + PLTE: color palette + IDAT: pixel data + IEND: the final chunk + tRNS: transparency for palettized images + tEXt: textual information + zTXt: compressed textual information + iTXt: international textual information + bKGD: suggested background color + pHYs: physical dimensions + tIME: modification time + +1.2. features not supported +--------------------------- + +The following features are _not_ supported: + +*) some features needed to make a conformant PNG-Editor might be still missing. +*) partial loading/stream processing. All data must be available and is processed in one call. +*) The following public chunks are not supported but treated as unknown chunks by LodePNG + cHRM, gAMA, iCCP, sRGB, sBIT, hIST, sPLT + Some of these are not supported on purpose: LodePNG wants to provide the RGB values + stored in the pixels, not values modified by system dependent gamma or color models. + + +2. C and C++ version +-------------------- + +The C version uses buffers allocated with alloc that you need to free() +yourself. You need to use init and cleanup functions for each struct whenever +using a struct from the C version to avoid exploits and memory leaks. + +The C++ version has extra functions with std::vectors in the interface and the +lodepng::State class which is a LodePNGState with constructor and destructor. + +These files work without modification for both C and C++ compilers because all +the additional C++ code is in "#ifdef __cplusplus" blocks that make C-compilers +ignore it, and the C code is made to compile both with strict ISO C90 and C++. + +To use the C++ version, you need to rename the source file to lodepng.cpp +(instead of lodepng.c), and compile it with a C++ compiler. + +To use the C version, you need to rename the source file to lodepng.c (instead +of lodepng.cpp), and compile it with a C compiler. + + +3. Security +----------- + +Even if carefully designed, it's always possible that LodePNG contains possible +exploits. If you discover one, please let me know, and it will be fixed. + +When using LodePNG, care has to be taken with the C version of LodePNG, as well +as the C-style structs when working with C++. The following conventions are used +for all C-style structs: + +-if a struct has a corresponding init function, always call the init function when making a new one +-if a struct has a corresponding cleanup function, call it before the struct disappears to avoid memory leaks +-if a struct has a corresponding copy function, use the copy function instead of "=". + The destination must also be inited already. + + +4. Decoding +----------- + +Decoding converts a PNG compressed image to a raw pixel buffer. + +Most documentation on using the decoder is at its declarations in the header +above. For C, simple decoding can be done with functions such as +lodepng_decode32, and more advanced decoding can be done with the struct +LodePNGState and lodepng_decode. For C++, all decoding can be done with the +various lodepng::decode functions, and lodepng::State can be used for advanced +features. + +When using the LodePNGState, it uses the following fields for decoding: +*) LodePNGInfo info_png: it stores extra information about the PNG (the input) in here +*) LodePNGColorMode info_raw: here you can say what color mode of the raw image (the output) you want to get +*) LodePNGDecoderSettings decoder: you can specify a few extra settings for the decoder to use + +LodePNGInfo info_png +-------------------- + +After decoding, this contains extra information of the PNG image, except the actual +pixels, width and height because these are already gotten directly from the decoder +functions. + +It contains for example the original color type of the PNG image, text comments, +suggested background color, etc... More details about the LodePNGInfo struct are +at its declaration documentation. + +LodePNGColorMode info_raw +------------------------- + +When decoding, here you can specify which color type you want +the resulting raw image to be. If this is different from the colortype of the +PNG, then the decoder will automatically convert the result. This conversion +always works, except if you want it to convert a color PNG to greyscale or to +a palette with missing colors. + +By default, 32-bit color is used for the result. + +LodePNGDecoderSettings decoder +------------------------------ + +The settings can be used to ignore the errors created by invalid CRC and Adler32 +chunks, and to disable the decoding of tEXt chunks. + +There's also a setting color_convert, true by default. If false, no conversion +is done, the resulting data will be as it was in the PNG (after decompression) +and you'll have to puzzle the colors of the pixels together yourself using the +color type information in the LodePNGInfo. + + +5. Encoding +----------- + +Encoding converts a raw pixel buffer to a PNG compressed image. + +Most documentation on using the encoder is at its declarations in the header +above. For C, simple encoding can be done with functions such as +lodepng_encode32, and more advanced decoding can be done with the struct +LodePNGState and lodepng_encode. For C++, all encoding can be done with the +various lodepng::encode functions, and lodepng::State can be used for advanced +features. + +Like the decoder, the encoder can also give errors. However it gives less errors +since the encoder input is trusted, the decoder input (a PNG image that could +be forged by anyone) is not trusted. + +When using the LodePNGState, it uses the following fields for encoding: +*) LodePNGInfo info_png: here you specify how you want the PNG (the output) to be. +*) LodePNGColorMode info_raw: here you say what color type of the raw image (the input) has +*) LodePNGEncoderSettings encoder: you can specify a few settings for the encoder to use + +LodePNGInfo info_png +-------------------- + +When encoding, you use this the opposite way as when decoding: for encoding, +you fill in the values you want the PNG to have before encoding. By default it's +not needed to specify a color type for the PNG since it's automatically chosen, +but it's possible to choose it yourself given the right settings. + +The encoder will not always exactly match the LodePNGInfo struct you give, +it tries as close as possible. Some things are ignored by the encoder. The +encoder uses, for example, the following settings from it when applicable: +colortype and bitdepth, text chunks, time chunk, the color key, the palette, the +background color, the interlace method, unknown chunks, ... + +When encoding to a PNG with colortype 3, the encoder will generate a PLTE chunk. +If the palette contains any colors for which the alpha channel is not 255 (so +there are translucent colors in the palette), it'll add a tRNS chunk. + +LodePNGColorMode info_raw +------------------------- + +You specify the color type of the raw image that you give to the input here, +including a possible transparent color key and palette you happen to be using in +your raw image data. + +By default, 32-bit color is assumed, meaning your input has to be in RGBA +format with 4 bytes (unsigned chars) per pixel. + +LodePNGEncoderSettings encoder +------------------------------ + +The following settings are supported (some are in sub-structs): +*) auto_convert: when this option is enabled, the encoder will +automatically choose the smallest possible color mode (including color key) that +can encode the colors of all pixels without information loss. +*) btype: the block type for LZ77. 0 = uncompressed, 1 = fixed huffman tree, + 2 = dynamic huffman tree (best compression). Should be 2 for proper + compression. +*) use_lz77: whether or not to use LZ77 for compressed block types. Should be + true for proper compression. +*) windowsize: the window size used by the LZ77 encoder (1 - 32768). Has value + 2048 by default, but can be set to 32768 for better, but slow, compression. +*) force_palette: if colortype is 2 or 6, you can make the encoder write a PLTE + chunk if force_palette is true. This can used as suggested palette to convert + to by viewers that don't support more than 256 colors (if those still exist) +*) add_id: add text chunk "Encoder: LodePNG " to the image. +*) text_compression: default 1. If 1, it'll store texts as zTXt instead of tEXt chunks. + zTXt chunks use zlib compression on the text. This gives a smaller result on + large texts but a larger result on small texts (such as a single program name). + It's all tEXt or all zTXt though, there's no separate setting per text yet. + + +6. color conversions +-------------------- + +An important thing to note about LodePNG, is that the color type of the PNG, and +the color type of the raw image, are completely independent. By default, when +you decode a PNG, you get the result as a raw image in the color type you want, +no matter whether the PNG was encoded with a palette, greyscale or RGBA color. +And if you encode an image, by default LodePNG will automatically choose the PNG +color type that gives good compression based on the values of colors and amount +of colors in the image. It can be configured to let you control it instead as +well, though. + +To be able to do this, LodePNG does conversions from one color mode to another. +It can convert from almost any color type to any other color type, except the +following conversions: RGB to greyscale is not supported, and converting to a +palette when the palette doesn't have a required color is not supported. This is +not supported on purpose: this is information loss which requires a color +reduction algorithm that is beyong the scope of a PNG encoder (yes, RGB to grey +is easy, but there are multiple ways if you want to give some channels more +weight). + +By default, when decoding, you get the raw image in 32-bit RGBA or 24-bit RGB +color, no matter what color type the PNG has. And by default when encoding, +LodePNG automatically picks the best color model for the output PNG, and expects +the input image to be 32-bit RGBA or 24-bit RGB. So, unless you want to control +the color format of the images yourself, you can skip this chapter. + +6.1. PNG color types +-------------------- + +A PNG image can have many color types, ranging from 1-bit color to 64-bit color, +as well as palettized color modes. After the zlib decompression and unfiltering +in the PNG image is done, the raw pixel data will have that color type and thus +a certain amount of bits per pixel. If you want the output raw image after +decoding to have another color type, a conversion is done by LodePNG. + +The PNG specification gives the following color types: + +0: greyscale, bit depths 1, 2, 4, 8, 16 +2: RGB, bit depths 8 and 16 +3: palette, bit depths 1, 2, 4 and 8 +4: greyscale with alpha, bit depths 8 and 16 +6: RGBA, bit depths 8 and 16 + +Bit depth is the amount of bits per pixel per color channel. So the total amount +of bits per pixel is: amount of channels * bitdepth. + +6.2. color conversions +---------------------- + +As explained in the sections about the encoder and decoder, you can specify +color types and bit depths in info_png and info_raw to change the default +behaviour. + +If, when decoding, you want the raw image to be something else than the default, +you need to set the color type and bit depth you want in the LodePNGColorMode, +or the parameters of the simple function of LodePNG you're using. + +If, when encoding, you use another color type than the default in the input +image, you need to specify its color type and bit depth in the LodePNGColorMode +of the raw image, or use the parameters of the simplefunction of LodePNG you're +using. + +If, when encoding, you don't want LodePNG to choose the output PNG color type +but control it yourself, you need to set auto_convert in the encoder settings +to LAC_NONE, and specify the color type you want in the LodePNGInfo of the +encoder. + +If you do any of the above, LodePNG may need to do a color conversion, which +follows the rules below, and may sometimes not be allowed. + +To avoid some confusion: +-the decoder converts from PNG to raw image +-the encoder converts from raw image to PNG +-the colortype and bitdepth in LodePNGColorMode info_raw, are those of the raw image +-the colortype and bitdepth in the color field of LodePNGInfo info_png, are those of the PNG +-when encoding, the color type in LodePNGInfo is ignored if auto_convert + is enabled, it is automatically generated instead +-when decoding, the color type in LodePNGInfo is set by the decoder to that of the original + PNG image, but it can be ignored since the raw image has the color type you requested instead +-if the color type of the LodePNGColorMode and PNG image aren't the same, a conversion + between the color types is done if the color types are supported. If it is not + supported, an error is returned. If the types are the same, no conversion is done. +-even though some conversions aren't supported, LodePNG supports loading PNGs from any + colortype and saving PNGs to any colortype, sometimes it just requires preparing + the raw image correctly before encoding. +-both encoder and decoder use the same color converter. + +Non supported color conversions: +-color to greyscale: no error is thrown, but the result will look ugly because +only the red channel is taken +-anything, to palette when that palette does not have that color in it: in this +case an error is thrown + +Supported color conversions: +-anything to 8-bit RGB, 8-bit RGBA, 16-bit RGB, 16-bit RGBA +-any grey or grey+alpha, to grey or grey+alpha +-anything to a palette, as long as the palette has the requested colors in it +-removing alpha channel +-higher to smaller bitdepth, and vice versa + +If you want no color conversion to be done: +-In the encoder, you can make it save a PNG with any color type by giving the +raw color mode and LodePNGInfo the same color mode, and setting auto_convert to +LAC_NO. +-In the decoder, you can make it store the pixel data in the same color type +as the PNG has, by setting the color_convert setting to false. Settings in +info_raw are then ignored. + +The function lodepng_convert does the color conversion. It is available in the +interface but normally isn't needed since the encoder and decoder already call +it. + +6.3. padding bits +----------------- + +In the PNG file format, if a less than 8-bit per pixel color type is used and the scanlines +have a bit amount that isn't a multiple of 8, then padding bits are used so that each +scanline starts at a fresh byte. But that is NOT true for the LodePNG raw input and output. +The raw input image you give to the encoder, and the raw output image you get from the decoder +will NOT have these padding bits, e.g. in the case of a 1-bit image with a width +of 7 pixels, the first pixel of the second scanline will the the 8th bit of the first byte, +not the first bit of a new byte. + + +7. error values +--------------- + +All functions in LodePNG that return an error code, return 0 if everything went +OK, or a non-zero code if there was an error. + +The meaning of the LodePNG error values can be retrieved with the function +lodepng_error_text: given the numerical error code, it returns a description +of the error in English as a string. + +Check the implementation of lodepng_error_text to see the meaning of each code. + + +8. chunks and PNG editing +------------------------- + +If you want to add extra chunks to a PNG you encode, or use LodePNG for a PNG +editor that should follow the rules about handling of unknown chunks, or if your +program is able to read other types of chunks than the ones handled by LodePNG, +then that's possible with the chunk functions of LodePNG. + +A PNG chunk has the following layout: + +4 bytes length +4 bytes type name +length bytes data +4 bytes CRC + +8.1. iterating through chunks +----------------------------- + +If you have a buffer containing the PNG image data, then the first chunk (the +IHDR chunk) starts at byte number 8 of that buffer. The first 8 bytes are the +signature of the PNG and are not part of a chunk. But if you start at byte 8 +then you have a chunk, and can check the following things of it. + +NOTE: none of these functions check for memory buffer boundaries. To avoid +exploits, always make sure the buffer contains all the data of the chunks. +When using lodepng_chunk_next, make sure the returned value is within the +allocated memory. + +unsigned lodepng_chunk_length(const unsigned char* chunk): + +Get the length of the chunk's data. The total chunk length is this length + 12. + +void lodepng_chunk_type(char type[5], const unsigned char* chunk): +unsigned char lodepng_chunk_type_equals(const unsigned char* chunk, const char* type): + +Get the type of the chunk or compare if it's a certain type + +unsigned char lodepng_chunk_critical(const unsigned char* chunk): +unsigned char lodepng_chunk_private(const unsigned char* chunk): +unsigned char lodepng_chunk_safetocopy(const unsigned char* chunk): + +Check if the chunk is critical in the PNG standard (only IHDR, PLTE, IDAT and IEND are). +Check if the chunk is private (public chunks are part of the standard, private ones not). +Check if the chunk is safe to copy. If it's not, then, when modifying data in a critical +chunk, unsafe to copy chunks of the old image may NOT be saved in the new one if your +program doesn't handle that type of unknown chunk. + +unsigned char* lodepng_chunk_data(unsigned char* chunk): +const unsigned char* lodepng_chunk_data_const(const unsigned char* chunk): + +Get a pointer to the start of the data of the chunk. + +unsigned lodepng_chunk_check_crc(const unsigned char* chunk): +void lodepng_chunk_generate_crc(unsigned char* chunk): + +Check if the crc is correct or generate a correct one. + +unsigned char* lodepng_chunk_next(unsigned char* chunk): +const unsigned char* lodepng_chunk_next_const(const unsigned char* chunk): + +Iterate to the next chunk. This works if you have a buffer with consecutive chunks. Note that these +functions do no boundary checking of the allocated data whatsoever, so make sure there is enough +data available in the buffer to be able to go to the next chunk. + +unsigned lodepng_chunk_append(unsigned char** out, size_t* outlength, const unsigned char* chunk): +unsigned lodepng_chunk_create(unsigned char** out, size_t* outlength, unsigned length, + const char* type, const unsigned char* data): + +These functions are used to create new chunks that are appended to the data in *out that has +length *outlength. The append function appends an existing chunk to the new data. The create +function creates a new chunk with the given parameters and appends it. Type is the 4-letter +name of the chunk. + +8.2. chunks in info_png +----------------------- + +The LodePNGInfo struct contains fields with the unknown chunk in it. It has 3 +buffers (each with size) to contain 3 types of unknown chunks: +the ones that come before the PLTE chunk, the ones that come between the PLTE +and the IDAT chunks, and the ones that come after the IDAT chunks. +It's necessary to make the distionction between these 3 cases because the PNG +standard forces to keep the ordering of unknown chunks compared to the critical +chunks, but does not force any other ordering rules. + +info_png.unknown_chunks_data[0] is the chunks before PLTE +info_png.unknown_chunks_data[1] is the chunks after PLTE, before IDAT +info_png.unknown_chunks_data[2] is the chunks after IDAT + +The chunks in these 3 buffers can be iterated through and read by using the same +way described in the previous subchapter. + +When using the decoder to decode a PNG, you can make it store all unknown chunks +if you set the option settings.remember_unknown_chunks to 1. By default, this +option is off (0). + +The encoder will always encode unknown chunks that are stored in the info_png. +If you need it to add a particular chunk that isn't known by LodePNG, you can +use lodepng_chunk_append or lodepng_chunk_create to the chunk data in +info_png.unknown_chunks_data[x]. + +Chunks that are known by LodePNG should not be added in that way. E.g. to make +LodePNG add a bKGD chunk, set background_defined to true and add the correct +parameters there instead. + + +9. compiler support +------------------- + +No libraries other than the current standard C library are needed to compile +LodePNG. For the C++ version, only the standard C++ library is needed on top. +Add the files lodepng.c(pp) and lodepng.h to your project, include +lodepng.h where needed, and your program can read/write PNG files. + +If performance is important, use optimization when compiling! For both the +encoder and decoder, this makes a large difference. + +Make sure that LodePNG is compiled with the same compiler of the same version +and with the same settings as the rest of the program, or the interfaces with +std::vectors and std::strings in C++ can be incompatible. + +CHAR_BITS must be 8 or higher, because LodePNG uses unsigned chars for octets. + +*) gcc and g++ + +LodePNG is developed in gcc so this compiler is natively supported. It gives no +warnings with compiler options "-Wall -Wextra -pedantic -ansi", with gcc and g++ +version 4.7.0 on Linux. + +*) Mingw + +The Mingw compiler (a port of gcc) for Windows is fully supported by LodePNG. + +*) Visual Studio 2005 and Visual C++ 2005 Express Edition + +Versions 20070604 up to 20080107 have been tested on VS2005 and work. Visual +studio may give warnings about 'fopen' being deprecated. A multiplatform library +can't support the proposed Visual Studio alternative however. + +If you're using LodePNG in VS2005 and don't want to see the deprecated warnings, +put this on top of lodepng.h before the inclusions: +#define _CRT_SECURE_NO_DEPRECATE + +Visual Studio may want "stdafx.h" files to be included in each source file. That +is not standard C++ and will not be added to the stock LodePNG. Try to find a +setting to disable it for this source file. + +*) Visual Studio 6.0 + +LodePNG support for Visual Studio 6.0 is not guaranteed because VS6 doesn't +follow the C++ standard correctly. + +*) Comeau C/C++ + +Vesion 20070107 compiles without problems on the Comeau C/C++ Online Test Drive +at http://www.comeaucomputing.com/tryitout in both C90 and C++ mode. + +*) Compilers on Macintosh + +LodePNG has been reported to work both with the gcc and LLVM for Macintosh, both +for C and C++. + +*) Other Compilers + +If you encounter problems on other compilers, feel free to let me know and I may +try to fix it if the compiler is modern standards complient. + + +10. examples +------------ + +This decoder example shows the most basic usage of LodePNG. More complex +examples can be found on the LodePNG website. + +10.1. decoder C++ example +------------------------- + +#include "lodepng.h" +#include + +int main(int argc, char *argv[]) +{ + const char* filename = argc > 1 ? argv[1] : "test.png"; + + //load and decode + std::vector image; + unsigned width, height; + unsigned error = lodepng::decode(image, width, height, filename); + + //if there's an error, display it + if(error) std::cout << "decoder error " << error << ": " << lodepng_error_text(error) << std::endl; + + //the pixels are now in the vector "image", 4 bytes per pixel, ordered RGBARGBA..., use it as texture, draw it, ... +} + +10.2. decoder C example +----------------------- + +#include "lodepng.h" + +int main(int argc, char *argv[]) +{ + unsigned error; + unsigned char* image; + size_t width, height; + const char* filename = argc > 1 ? argv[1] : "test.png"; + + error = lodepng_decode32_file(&image, &width, &height, filename); + + if(error) printf("decoder error %u: %s\n", error, lodepng_error_text(error)); + + / * use image here * / + + free(image); + return 0; +} + + +11. changes +----------- + +The version number of LodePNG is the date of the change given in the format +yyyymmdd. + +Some changes aren't backwards compatible. Those are indicated with a (!) +symbol. + +*) 23 jun 2012: Added more filter strategies. Made it easier to use custom alloc + and free functions and toggle #defines from compiler flags. Small fixes. +*) 6 may 2012 (!): Made plugging in custom zlib/deflate functions more flexible. +*) 22 apr 2012 (!): Made interface more consistent, renaming a lot. Removed + redundant C++ codec classes. Reduced amount of structs. Everything changed, + but it is cleaner now imho and functionality remains the same. Also fixed + several bugs and shrinked the implementation code. Made new samples. +*) 6 nov 2011 (!): By default, the encoder now automatically chooses the best + PNG color model and bit depth, based on the amount and type of colors of the + raw image. For this, autoLeaveOutAlphaChannel replaced by auto_choose_color. +*) 9 okt 2011: simpler hash chain implementation for the encoder. +*) 8 sep 2011: lz77 encoder lazy matching instead of greedy matching. +*) 23 aug 2011: tweaked the zlib compression parameters after benchmarking. + A bug with the PNG filtertype heuristic was fixed, so that it chooses much + better ones (it's quite significant). A setting to do an experimental, slow, + brute force search for PNG filter types is added. +*) 17 aug 2011 (!): changed some C zlib related function names. +*) 16 aug 2011: made the code less wide (max 120 characters per line). +*) 17 apr 2011: code cleanup. Bugfixes. Convert low to 16-bit per sample colors. +*) 21 feb 2011: fixed compiling for C90. Fixed compiling with sections disabled. +*) 11 dec 2010: encoding is made faster, based on suggestion by Peter Eastman + to optimize long sequences of zeros. +*) 13 nov 2010: added LodePNG_InfoColor_hasPaletteAlpha and + LodePNG_InfoColor_canHaveAlpha functions for convenience. +*) 7 nov 2010: added LodePNG_error_text function to get error code description. +*) 30 okt 2010: made decoding slightly faster +*) 26 okt 2010: (!) changed some C function and struct names (more consistent). + Reorganized the documentation and the declaration order in the header. +*) 08 aug 2010: only changed some comments and external samples. +*) 05 jul 2010: fixed bug thanks to warnings in the new gcc version. +*) 14 mar 2010: fixed bug where too much memory was allocated for char buffers. +*) 02 sep 2008: fixed bug where it could create empty tree that linux apps could + read by ignoring the problem but windows apps couldn't. +*) 06 jun 2008: added more error checks for out of memory cases. +*) 26 apr 2008: added a few more checks here and there to ensure more safety. +*) 06 mar 2008: crash with encoding of strings fixed +*) 02 feb 2008: support for international text chunks added (iTXt) +*) 23 jan 2008: small cleanups, and #defines to divide code in sections +*) 20 jan 2008: support for unknown chunks allowing using LodePNG for an editor. +*) 18 jan 2008: support for tIME and pHYs chunks added to encoder and decoder. +*) 17 jan 2008: ability to encode and decode compressed zTXt chunks added + Also vareous fixes, such as in the deflate and the padding bits code. +*) 13 jan 2008: Added ability to encode Adam7-interlaced images. Improved + filtering code of encoder. +*) 07 jan 2008: (!) changed LodePNG to use ISO C90 instead of C++. A + C++ wrapper around this provides an interface almost identical to before. + Having LodePNG be pure ISO C90 makes it more portable. The C and C++ code + are together in these files but it works both for C and C++ compilers. +*) 29 dec 2007: (!) changed most integer types to unsigned int + other tweaks +*) 30 aug 2007: bug fixed which makes this Borland C++ compatible +*) 09 aug 2007: some VS2005 warnings removed again +*) 21 jul 2007: deflate code placed in new namespace separate from zlib code +*) 08 jun 2007: fixed bug with 2- and 4-bit color, and small interlaced images +*) 04 jun 2007: improved support for Visual Studio 2005: crash with accessing + invalid std::vector element [0] fixed, and level 3 and 4 warnings removed +*) 02 jun 2007: made the encoder add a tag with version by default +*) 27 may 2007: zlib and png code separated (but still in the same file), + simple encoder/decoder functions added for more simple usage cases +*) 19 may 2007: minor fixes, some code cleaning, new error added (error 69), + moved some examples from here to lodepng_examples.cpp +*) 12 may 2007: palette decoding bug fixed +*) 24 apr 2007: changed the license from BSD to the zlib license +*) 11 mar 2007: very simple addition: ability to encode bKGD chunks. +*) 04 mar 2007: (!) tEXt chunk related fixes, and support for encoding + palettized PNG images. Plus little interface change with palette and texts. +*) 03 mar 2007: Made it encode dynamic Huffman shorter with repeat codes. + Fixed a bug where the end code of a block had length 0 in the Huffman tree. +*) 26 feb 2007: Huffman compression with dynamic trees (BTYPE 2) now implemented + and supported by the encoder, resulting in smaller PNGs at the output. +*) 27 jan 2007: Made the Adler-32 test faster so that a timewaste is gone. +*) 24 jan 2007: gave encoder an error interface. Added color conversion from any + greyscale type to 8-bit greyscale with or without alpha. +*) 21 jan 2007: (!) Totally changed the interface. It allows more color types + to convert to and is more uniform. See the manual for how it works now. +*) 07 jan 2007: Some cleanup & fixes, and a few changes over the last days: + encode/decode custom tEXt chunks, separate classes for zlib & deflate, and + at last made the decoder give errors for incorrect Adler32 or Crc. +*) 01 jan 2007: Fixed bug with encoding PNGs with less than 8 bits per channel. +*) 29 dec 2006: Added support for encoding images without alpha channel, and + cleaned out code as well as making certain parts faster. +*) 28 dec 2006: Added "Settings" to the encoder. +*) 26 dec 2006: The encoder now does LZ77 encoding and produces much smaller files now. + Removed some code duplication in the decoder. Fixed little bug in an example. +*) 09 dec 2006: (!) Placed output parameters of public functions as first parameter. + Fixed a bug of the decoder with 16-bit per color. +*) 15 okt 2006: Changed documentation structure +*) 09 okt 2006: Encoder class added. It encodes a valid PNG image from the + given image buffer, however for now it's not compressed. +*) 08 sep 2006: (!) Changed to interface with a Decoder class +*) 30 jul 2006: (!) LodePNG_InfoPng , width and height are now retrieved in different + way. Renamed decodePNG to decodePNGGeneric. +*) 29 jul 2006: (!) Changed the interface: image info is now returned as a + struct of type LodePNG::LodePNG_Info, instead of a vector, which was a bit clumsy. +*) 28 jul 2006: Cleaned the code and added new error checks. + Corrected terminology "deflate" into "inflate". +*) 23 jun 2006: Added SDL example in the documentation in the header, this + example allows easy debugging by displaying the PNG and its transparency. +*) 22 jun 2006: (!) Changed way to obtain error value. Added + loadFile function for convenience. Made decodePNG32 faster. +*) 21 jun 2006: (!) Changed type of info vector to unsigned. + Changed position of palette in info vector. Fixed an important bug that + happened on PNGs with an uncompressed block. +*) 16 jun 2006: Internally changed unsigned into unsigned where + needed, and performed some optimizations. +*) 07 jun 2006: (!) Renamed functions to decodePNG and placed them + in LodePNG namespace. Changed the order of the parameters. Rewrote the + documentation in the header. Renamed files to lodepng.cpp and lodepng.h +*) 22 apr 2006: Optimized and improved some code +*) 07 sep 2005: (!) Changed to std::vector interface +*) 12 aug 2005: Initial release (C++, decoder only) + + +12. contact information +----------------------- + +Feel free to contact me with suggestions, problems, comments, ... concerning +LodePNG. If you encounter a PNG image that doesn't work properly with this +decoder, feel free to send it and I'll use it to find and fix the problem. + +My email address is (puzzle the account and domain together with an @ symbol): +Domain: gmail dot com. +Account: lode dot vandevenne. + + +Copyright (c) 2005-2012 Lode Vandevenne +*/ diff --git a/lib/gui/picopng.c b/lib/gui/picopng.c new file mode 100644 index 0000000..77cd81c --- /dev/null +++ b/lib/gui/picopng.c @@ -0,0 +1,810 @@ +// picoPNG version 20080503 (cleaned up and ported to c by kaitek) +// Copyright (c) 2005-2008 Lode Vandevenne +// +// This software is provided 'as-is', without any express or implied +// warranty. In no event will the authors be held liable for any damages +// arising from the use of this software. +// +// Permission is granted to anyone to use this software for any purpose, +// including commercial applications, and to alter it and redistribute it +// freely, subject to the following restrictions: +// +// 1. The origin of this software must not be misrepresented; you must not +// claim that you wrote the original software. If you use this software +// in a product, an acknowledgment in the product documentation would be +// appreciated but is not required. +// 2. Altered source versions must be plainly marked as such, and must not be +// misrepresented as being the original software. +// 3. This notice may not be removed or altered from any source distribution. + +#include +#include +#include "picopng.h" + +/*************************************************************************************************/ + +typedef struct png_alloc_node { + struct png_alloc_node *prev, *next; + void *addr; + size_t size; +} png_alloc_node_t; + +png_alloc_node_t *png_alloc_head = NULL; +png_alloc_node_t *png_alloc_tail = NULL; + +png_alloc_node_t *png_alloc_find_node(void *addr) +{ + png_alloc_node_t *node; + for (node = png_alloc_head; node; node = node->next) + if (node->addr == addr) + break; + return node; +} + +void png_alloc_add_node(void *addr, size_t size) +{ + png_alloc_node_t *node; + if (png_alloc_find_node(addr)) + return; + node = malloc(sizeof (png_alloc_node_t)); + node->addr = addr; + node->size = size; + node->prev = png_alloc_tail; + node->next = NULL; + png_alloc_tail = node; + if (node->prev) + node->prev->next = node; + if (!png_alloc_head) + png_alloc_head = node; +} + +void png_alloc_remove_node(png_alloc_node_t *node) +{ + if (node->prev) + node->prev->next = node->next; + if (node->next) + node->next->prev = node->prev; + if (node == png_alloc_head) + png_alloc_head = node->next; + if (node == png_alloc_tail) + png_alloc_tail = node->prev; + node->prev = node->next = node->addr = NULL; + free(node); +} + +void *png_alloc_malloc(size_t size) +{ + void *addr = malloc(size); + png_alloc_add_node(addr, size); + return addr; +} + +void *png_alloc_realloc(void *addr, size_t size) +{ + void *new_addr; + if (!addr) + return png_alloc_malloc(size); + new_addr = realloc(addr, size); + if (new_addr != addr) { + png_alloc_node_t *old_node; + old_node = png_alloc_find_node(addr); + png_alloc_remove_node(old_node); + png_alloc_add_node(new_addr, size); + } + return new_addr; +} + +void png_alloc_free(void *addr) +{ + png_alloc_node_t *node = png_alloc_find_node(addr); + if (!node) + return; + png_alloc_remove_node(node); + free(addr); +} + +void png_alloc_free_all() +{ + while (png_alloc_tail) { + void *addr = png_alloc_tail->addr; + png_alloc_remove_node(png_alloc_tail); + free(addr); + } +} + +/*************************************************************************************************/ + +__maybe_unused void vector32_cleanup(vector32_t *p) +{ + p->size = p->allocsize = 0; + if (p->data) + png_alloc_free(p->data); + p->data = NULL; +} + +uint32_t vector32_resize(vector32_t *p, size_t size) +{ // returns 1 if success, 0 if failure ==> nothing done + if (size * sizeof (uint32_t) > p->allocsize) { + size_t newsize = size * sizeof (uint32_t) * 2; + void *data = png_alloc_realloc(p->data, newsize); + if (data) { + p->allocsize = newsize; + p->data = (uint32_t *) data; + p->size = size; + } else + return 0; + } else + p->size = size; + return 1; +} + +uint32_t vector32_resizev(vector32_t *p, size_t size, uint32_t value) +{ // resize and give all new elements the value + size_t oldsize = p->size, i; + if (!vector32_resize(p, size)) + return 0; + for (i = oldsize; i < size; i++) + p->data[i] = value; + return 1; +} + +void vector32_init(vector32_t *p) +{ + p->data = NULL; + p->size = p->allocsize = 0; +} + +vector32_t *vector32_new(size_t size, uint32_t value) +{ + vector32_t *p = png_alloc_malloc(sizeof (vector32_t)); + vector32_init(p); + if (size && !vector32_resizev(p, size, value)) + return NULL; + return p; +} + +/*************************************************************************************************/ + +__maybe_unused void vector8_cleanup(vector8_t *p) +{ + p->size = p->allocsize = 0; + if (p->data) + png_alloc_free(p->data); + p->data = NULL; +} + +uint32_t vector8_resize(vector8_t *p, size_t size) +{ // returns 1 if success, 0 if failure ==> nothing done + // xxx: the use of sizeof uint32_t here seems like a bug (this descends from the lodepng vector + // compatibility functions which do the same). without this there is corruption in certain cases, + // so this was probably done to cover up allocation bug(s) in the original picopng code! + if (size * sizeof (uint32_t) > p->allocsize) { + size_t newsize = size * sizeof (uint32_t) * 2; + void *data = png_alloc_realloc(p->data, newsize); + if (data) { + p->allocsize = newsize; + p->data = (uint8_t *) data; + p->size = size; + } else + return 0; // error: not enough memory + } else + p->size = size; + return 1; +} + +uint32_t vector8_resizev(vector8_t *p, size_t size, uint8_t value) +{ // resize and give all new elements the value + size_t oldsize = p->size, i; + if (!vector8_resize(p, size)) + return 0; + for (i = oldsize; i < size; i++) + p->data[i] = value; + return 1; +} + +void vector8_init(vector8_t *p) +{ + p->data = NULL; + p->size = p->allocsize = 0; +} + +vector8_t *vector8_new(size_t size, uint8_t value) +{ + vector8_t *p = png_alloc_malloc(sizeof (vector8_t)); + vector8_init(p); + if (size && !vector8_resizev(p, size, value)) + return NULL; + return p; +} + +vector8_t *vector8_copy(vector8_t *p) +{ + vector8_t *q = vector8_new(p->size, 0); + uint32_t n; + for (n = 0; n < q->size; n++) + q->data[n] = p->data[n]; + return q; +} + +/*************************************************************************************************/ +int Zlib_decompress(vector8_t *out, const vector8_t *in) // returns error value +{ + return picopng_zlib_decompress(out->data, out->size, in->data, in->size); +} + +/*************************************************************************************************/ + +#define PNG_SIGNATURE 0x0a1a0a0d474e5089ull + +#define CHUNK_IHDR 0x52444849 +#define CHUNK_IDAT 0x54414449 +#define CHUNK_IEND 0x444e4549 +#define CHUNK_PLTE 0x45544c50 +#define CHUNK_tRNS 0x534e5274 + +int PNG_error; + +uint32_t PNG_readBitFromReversedStream(size_t *bitp, const uint8_t *bits) +{ + uint32_t result = (bits[*bitp >> 3] >> (7 - (*bitp & 0x7))) & 1; + (*bitp)++; + return result; +} + +uint32_t PNG_readBitsFromReversedStream(size_t *bitp, const uint8_t *bits, uint32_t nbits) +{ + uint32_t i, result = 0; + for (i = nbits - 1; i < nbits; i--) + result += ((PNG_readBitFromReversedStream(bitp, bits)) << i); + return result; +} + +void PNG_setBitOfReversedStream(size_t *bitp, uint8_t *bits, uint32_t bit) +{ + bits[*bitp >> 3] |= (bit << (7 - (*bitp & 0x7))); + (*bitp)++; +} + +uint32_t PNG_read32bitInt(const uint8_t *buffer) +{ + return (buffer[0] << 24) | (buffer[1] << 16) | (buffer[2] << 8) | buffer[3]; +} + +int PNG_checkColorValidity(uint32_t colorType, uint32_t bd) // return type is a LodePNG error code +{ + if ((colorType == 2 || colorType == 4 || colorType == 6)) { + if (!(bd == 8 || bd == 16)) + return 37; + else + return 0; + } else if (colorType == 0) { + if (!(bd == 1 || bd == 2 || bd == 4 || bd == 8 || bd == 16)) + return 37; + else + return 0; + } else if (colorType == 3) { + if (!(bd == 1 || bd == 2 || bd == 4 || bd == 8)) + return 37; + else + return 0; + } else + return 31; // nonexistent color type +} + +uint32_t PNG_getBpp(const PNG_info_t *info) +{ + uint32_t bitDepth, colorType; + bitDepth = info->bitDepth; + colorType = info->colorType; + if (colorType == 2) + return (3 * bitDepth); + else if (colorType >= 4) + return (colorType - 2) * bitDepth; + else + return bitDepth; +} + +void PNG_readPngHeader(PNG_info_t *info, const uint8_t *in, size_t inlength) +{ // read the information from the header and store it in the Info + if (inlength < 29) { + PNG_error = 27; // error: the data length is smaller than the length of the header + return; + } + if (*(uint64_t *) in != PNG_SIGNATURE) { + PNG_error = 28; // no PNG signature + return; + } + if (*(uint32_t *) &in[12] != CHUNK_IHDR) { + PNG_error = 29; // error: it doesn't start with a IHDR chunk! + return; + } + info->width = PNG_read32bitInt(&in[16]); + info->height = PNG_read32bitInt(&in[20]); + info->bitDepth = in[24]; + info->colorType = in[25]; + info->compressionMethod = in[26]; + if (in[26] != 0) { + PNG_error = 32; // error: only compression method 0 is allowed in the specification + return; + } + info->filterMethod = in[27]; + if (in[27] != 0) { + PNG_error = 33; // error: only filter method 0 is allowed in the specification + return; + } + info->interlaceMethod = in[28]; + if (in[28] > 1) { + PNG_error = 34; // error: only interlace methods 0 and 1 exist in the specification + return; + } + PNG_error = PNG_checkColorValidity(info->colorType, info->bitDepth); +} + +int PNG_paethPredictor(int a, int b, int c) // Paeth predicter, used by PNG filter type 4 +{ + int p, pa, pb, pc; + p = a + b - c; + pa = p > a ? (p - a) : (a - p); + pb = p > b ? (p - b) : (b - p); + pc = p > c ? (p - c) : (c - p); + return (pa <= pb && pa <= pc) ? a : (pb <= pc ? b : c); +} + +void PNG_unFilterScanline(uint8_t *recon, const uint8_t *scanline, const uint8_t *precon, + size_t bytewidth, uint32_t filterType, size_t length) +{ + size_t i; + switch (filterType) { + case 0: + for (i = 0; i < length; i++) + recon[i] = scanline[i]; + break; + case 1: + for (i = 0; i < bytewidth; i++) + recon[i] = scanline[i]; + for (i = bytewidth; i < length; i++) + recon[i] = scanline[i] + recon[i - bytewidth]; + break; + case 2: + if (precon) + for (i = 0; i < length; i++) + recon[i] = scanline[i] + precon[i]; + else + for (i = 0; i < length; i++) + recon[i] = scanline[i]; + break; + case 3: + if (precon) { + for (i = 0; i < bytewidth; i++) + recon[i] = scanline[i] + precon[i] / 2; + for (i = bytewidth; i < length; i++) + recon[i] = scanline[i] + ((recon[i - bytewidth] + precon[i]) / 2); + } else { + for (i = 0; i < bytewidth; i++) + recon[i] = scanline[i]; + for (i = bytewidth; i < length; i++) + recon[i] = scanline[i] + recon[i - bytewidth] / 2; + } + break; + case 4: + if (precon) { + for (i = 0; i < bytewidth; i++) + recon[i] = (uint8_t) (scanline[i] + PNG_paethPredictor(0, precon[i], 0)); + for (i = bytewidth; i < length; i++) + recon[i] = (uint8_t) (scanline[i] + PNG_paethPredictor(recon[i - bytewidth], + precon[i], precon[i - bytewidth])); + } else { + for (i = 0; i < bytewidth; i++) + recon[i] = scanline[i]; + for (i = bytewidth; i < length; i++) + recon[i] = (uint8_t) (scanline[i] + PNG_paethPredictor(recon[i - bytewidth], 0, 0)); + } + break; + default: + PNG_error = 36; // error: nonexistent filter type given + return; + } +} + +void PNG_adam7Pass(uint8_t *out, uint8_t *linen, uint8_t *lineo, const uint8_t *in, uint32_t w, + size_t passleft, size_t passtop, size_t spacex, size_t spacey, size_t passw, size_t passh, + uint32_t bpp) +{ + size_t bytewidth, linelength; + uint32_t y; + uint8_t *temp; + // filter and reposition the pixels into the output when the image is Adam7 interlaced. This + // function can only do it after the full image is already decoded. The out buffer must have + // the correct allocated memory size already. + if (passw == 0) + return; + bytewidth = (bpp + 7) / 8; + linelength = 1 + ((bpp * passw + 7) / 8); + for (y = 0; y < passh; y++) { + size_t i, b; + uint8_t filterType = in[y * linelength], *prevline = (y == 0) ? 0 : lineo; + PNG_unFilterScanline(linen, &in[y * linelength + 1], prevline, bytewidth, filterType, + (w * bpp + 7) / 8); + if (PNG_error) + return; + if (bpp >= 8) + for (i = 0; i < passw; i++) + for (b = 0; b < bytewidth; b++) // b = current byte of this pixel + out[bytewidth * w * (passtop + spacey * y) + bytewidth * + (passleft + spacex * i) + b] = linen[bytewidth * i + b]; + else + for (i = 0; i < passw; i++) { + size_t obp, bp; + obp = bpp * w * (passtop + spacey * y) + bpp * (passleft + spacex * i); + bp = i * bpp; + for (b = 0; b < bpp; b++) + PNG_setBitOfReversedStream(&obp, out, PNG_readBitFromReversedStream(&bp, linen)); + } + temp = linen; + linen = lineo; + lineo = temp; // swap the two buffer pointers "line old" and "line new" + } +} + +int PNG_convert(const PNG_info_t *info, vector8_t *out, const uint8_t *in) +{ // converts from any color type to 32-bit. return value = LodePNG error code + size_t i, c; + uint32_t bitDepth, colorType; + size_t numpixels, bp; + uint8_t *out_data; + + bitDepth = info->bitDepth; + colorType = info->colorType; + numpixels = info->width * info->height; + bp = 0; + vector8_resize(out, numpixels * 4); + out_data = out->size ? out->data : 0; + if (bitDepth == 8 && colorType == 0) // greyscale + for (i = 0; i < numpixels; i++) { + out_data[4 * i + 0] = out_data[4 * i + 1] = out_data[4 * i + 2] = in[i]; + out_data[4 * i + 3] = (info->key_defined && (in[i] == info->key_r)) ? 0 : 255; + } + else if (bitDepth == 8 && colorType == 2) // RGB color + for (i = 0; i < numpixels; i++) { + for (c = 0; c < 3; c++) + out_data[4 * i + c] = in[3 * i + c]; + out_data[4 * i + 3] = (info->key_defined && (in[3 * i + 0] == info->key_r) && + (in[3 * i + 1] == info->key_g) && (in[3 * i + 2] == info->key_b)) ? 0 : 255; + } + else if (bitDepth == 8 && colorType == 3) // indexed color (palette) + for (i = 0; i < numpixels; i++) { + if (4U * in[i] >= info->palette->size) + return 46; + for (c = 0; c < 4; c++) // get rgb colors from the palette + out_data[4 * i + c] = info->palette->data[4 * in[i] + c]; + } + else if (bitDepth == 8 && colorType == 4) // greyscale with alpha + for (i = 0; i < numpixels; i++) { + out_data[4 * i + 0] = out_data[4 * i + 1] = out_data[4 * i + 2] = in[2 * i + 0]; + out_data[4 * i + 3] = in[2 * i + 1]; + } + else if (bitDepth == 8 && colorType == 6) + for (i = 0; i < numpixels; i++) + for (c = 0; c < 4; c++) + out_data[4 * i + c] = in[4 * i + c]; // RGB with alpha + else if (bitDepth == 16 && colorType == 0) // greyscale + for (i = 0; i < numpixels; i++) { + out_data[4 * i + 0] = out_data[4 * i + 1] = out_data[4 * i + 2] = in[2 * i]; + out_data[4 * i + 3] = (info->key_defined && (256U * in[i] + in[i + 1] == info->key_r)) + ? 0 : 255; + } + else if (bitDepth == 16 && colorType == 2) // RGB color + for (i = 0; i < numpixels; i++) { + for (c = 0; c < 3; c++) + out_data[4 * i + c] = in[6 * i + 2 * c]; + out_data[4 * i + 3] = (info->key_defined && + (256U * in[6 * i + 0] + in[6 * i + 1] == info->key_r) && + (256U * in[6 * i + 2] + in[6 * i + 3] == info->key_g) && + (256U * in[6 * i + 4] + in[6 * i + 5] == info->key_b)) ? 0 : 255; + } + else if (bitDepth == 16 && colorType == 4) // greyscale with alpha + for (i = 0; i < numpixels; i++) { + out_data[4 * i + 0] = out_data[4 * i + 1] = out_data[4 * i + 2] = in[4 * i]; // msb + out_data[4 * i + 3] = in[4 * i + 2]; + } + else if (bitDepth == 16 && colorType == 6) + for (i = 0; i < numpixels; i++) + for (c = 0; c < 4; c++) + out_data[4 * i + c] = in[8 * i + 2 * c]; // RGB with alpha + else if (bitDepth < 8 && colorType == 0) // greyscale + for (i = 0; i < numpixels; i++) { + uint32_t value = (PNG_readBitsFromReversedStream(&bp, in, bitDepth) * 255) / + ((1 << bitDepth) - 1); // scale value from 0 to 255 + out_data[4 * i + 0] = out_data[4 * i + 1] = out_data[4 * i + 2] = (uint8_t) value; + out_data[4 * i + 3] = (info->key_defined && value && + (((1U << bitDepth) - 1U) == info->key_r) && ((1U << bitDepth) - 1U)) ? 0 : 255; + } + else if (bitDepth < 8 && colorType == 3) // palette + for (i = 0; i < numpixels; i++) { + uint32_t value = PNG_readBitsFromReversedStream(&bp, in, bitDepth); + if (4 * value >= info->palette->size) + return 47; + for (c = 0; c < 4; c++) // get rgb colors from the palette + out_data[4 * i + c] = info->palette->data[4 * value + c]; + } + return 0; +} + +PNG_info_t *PNG_info_new(void) +{ + PNG_info_t *info = png_alloc_malloc(sizeof (PNG_info_t)); + uint32_t i; + for (i = 0; i < sizeof (PNG_info_t); i++) + ((uint8_t *) info)[i] = 0; + info->palette = vector8_new(0, 0); + info->image = vector8_new(0, 0); + return info; +} + +PNG_info_t *PNG_decode(const uint8_t *in, uint32_t size) +{ + PNG_info_t *info; + size_t pos; + vector8_t *idat; + bool IEND, known_type; + uint32_t bpp; + vector8_t *scanlines; // now the out buffer will be filled + size_t bytewidth, outlength; + uint8_t *out_data; + + PNG_error = 0; + + if (size == 0 || in == 0) { + PNG_error = 48; // the given data is empty + return NULL; + } + info = PNG_info_new(); + PNG_readPngHeader(info, in, size); + if (PNG_error) + return NULL; + pos = 33; // first byte of the first chunk after the header + idat = NULL; // the data from idat chunks + IEND = false; + known_type = true; + info->key_defined = false; + // loop through the chunks, ignoring unknown chunks and stopping at IEND chunk. IDAT data is + // put at the start of the in buffer + while (!IEND) { + size_t i, j; + size_t chunkLength; + uint32_t chunkType; + + if (pos + 8 >= size) { + PNG_error = 30; // error: size of the in buffer too small to contain next chunk + return NULL; + } + chunkLength = PNG_read32bitInt(&in[pos]); + pos += 4; + if (chunkLength > 0x7fffffff) { + PNG_error = 63; + return NULL; + } + if (pos + chunkLength >= size) { + PNG_error = 35; // error: size of the in buffer too small to contain next chunk + return NULL; + } + chunkType = *(uint32_t *) &in[pos]; + if (chunkType == CHUNK_IDAT) { // IDAT: compressed image data chunk + size_t offset = 0; + if (idat) { + offset = idat->size; + vector8_resize(idat, offset + chunkLength); + } else + idat = vector8_new(chunkLength, 0); + for (i = 0; i < chunkLength; i++) + idat->data[offset + i] = in[pos + 4 + i]; + pos += (4 + chunkLength); + } else if (chunkType == CHUNK_IEND) { // IEND + pos += 4; + IEND = true; + } else if (chunkType == CHUNK_PLTE) { // PLTE: palette chunk + pos += 4; // go after the 4 letters + vector8_resize(info->palette, 4 * (chunkLength / 3)); + if (info->palette->size > (4 * 256)) { + PNG_error = 38; // error: palette too big + return NULL; + } + for (i = 0; i < info->palette->size; i += 4) { + for (j = 0; j < 3; j++) + info->palette->data[i + j] = in[pos++]; // RGB + info->palette->data[i + 3] = 255; // alpha + } + } else if (chunkType == CHUNK_tRNS) { // tRNS: palette transparency chunk + pos += 4; // go after the 4 letters + if (info->colorType == 3) { + if (4 * chunkLength > info->palette->size) { + PNG_error = 39; // error: more alpha values given than there are palette entries + return NULL; + } + for (i = 0; i < chunkLength; i++) + info->palette->data[4 * i + 3] = in[pos++]; + } else if (info->colorType == 0) { + if (chunkLength != 2) { + PNG_error = 40; // error: this chunk must be 2 bytes for greyscale image + return NULL; + } + info->key_defined = true; + info->key_r = info->key_g = info->key_b = 256 * in[pos] + in[pos + 1]; + pos += 2; + } else if (info->colorType == 2) { + if (chunkLength != 6) { + PNG_error = 41; // error: this chunk must be 6 bytes for RGB image + return NULL; + } + info->key_defined = true; + info->key_r = 256 * in[pos] + in[pos + 1]; + pos += 2; + info->key_g = 256 * in[pos] + in[pos + 1]; + pos += 2; + info->key_b = 256 * in[pos] + in[pos + 1]; + pos += 2; + } else { + PNG_error = 42; // error: tRNS chunk not allowed for other color models + return NULL; + } + } else { // it's not an implemented chunk type, so ignore it: skip over the data + if (!(in[pos + 0] & 32)) { + // error: unknown critical chunk (5th bit of first byte of chunk type is 0) + PNG_error = 69; + return NULL; + } + pos += (chunkLength + 4); // skip 4 letters and uninterpreted data of unimplemented chunk + known_type = false; + } + pos += 4; // step over CRC (which is ignored) + } + bpp = PNG_getBpp(info); + scanlines = vector8_new(((info->width * (info->height * bpp + 7)) / 8) + info->height, 0); + PNG_error = Zlib_decompress(scanlines, idat); + if (PNG_error) + return NULL; // stop if the zlib decompressor returned an error + bytewidth = (bpp + 7) / 8; + outlength = (info->height * info->width * bpp + 7) / 8; + vector8_resize(info->image, outlength); // time to fill the out buffer + out_data = outlength ? info->image->data : 0; + if (info->interlaceMethod == 0) { // no interlace, just filter + size_t y, obp, bp; + size_t linestart, linelength; + linestart = 0; + // length in bytes of a scanline, excluding the filtertype byte + linelength = (info->width * bpp + 7) / 8; + if (bpp >= 8) // byte per byte + for (y = 0; y < info->height; y++) { + uint32_t filterType = scanlines->data[linestart]; + const uint8_t *prevline; + prevline = (y == 0) ? 0 : &out_data[(y - 1) * info->width * bytewidth]; + PNG_unFilterScanline(&out_data[linestart - y], &scanlines->data[linestart + 1], + prevline, bytewidth, filterType, linelength); + if (PNG_error) + return NULL; + linestart += (1 + linelength); // go to start of next scanline + } else { // less than 8 bits per pixel, so fill it up bit per bit + vector8_t *templine; // only used if bpp < 8 + templine = vector8_new((info->width * bpp + 7) >> 3, 0); + for (y = 0, obp = 0; y < info->height; y++) { + uint32_t filterType = scanlines->data[linestart]; + const uint8_t *prevline; + prevline = (y == 0) ? 0 : &out_data[(y - 1) * info->width * bytewidth]; + PNG_unFilterScanline(templine->data, &scanlines->data[linestart + 1], prevline, + bytewidth, filterType, linelength); + if (PNG_error) + return NULL; + for (bp = 0; bp < info->width * bpp;) + PNG_setBitOfReversedStream(&obp, out_data, PNG_readBitFromReversedStream(&bp, + templine->data)); + linestart += (1 + linelength); // go to start of next scanline + } + } + } else { // interlaceMethod is 1 (Adam7) + int i; + vector8_t *scanlineo, *scanlinen; // "old" and "new" scanline + size_t passw[7] = { + (info->width + 7) / 8, (info->width + 3) / 8, (info->width + 3) / 4, + (info->width + 1) / 4, (info->width + 1) / 2, (info->width + 0) / 2, + (info->width + 0) / 1 + }; + size_t passh[7] = { + (info->height + 7) / 8, (info->height + 7) / 8, (info->height + 3) / 8, + (info->height + 3) / 4, (info->height + 1) / 4, (info->height + 1) / 2, + (info->height + 0) / 2 + }; + size_t passstart[7] = { 0 }; + size_t pattern[28] = { 0, 4, 0, 2, 0, 1, 0, 0, 0, 4, 0, 2, 0, 1, 8, 8, 4, 4, 2, 2, 1, 8, 8, + 8, 4, 4, 2, 2 }; // values for the adam7 passes + for (i = 0; i < 6; i++) + passstart[i + 1] = passstart[i] + passh[i] * ((passw[i] ? 1 : 0) + (passw[i] * bpp + 7) / 8); + scanlineo = vector8_new((info->width * bpp + 7) / 8, 0); + scanlinen = vector8_new((info->width * bpp + 7) / 8, 0); + for (i = 0; i < 7; i++) + PNG_adam7Pass(out_data, scanlinen->data, scanlineo->data, &scanlines->data[passstart[i]], + info->width, pattern[i], pattern[i + 7], pattern[i + 14], pattern[i + 21], + passw[i], passh[i], bpp); + } + if (info->colorType != 6 || info->bitDepth != 8) { // conversion needed + vector8_t *copy = vector8_copy(info->image); // xxx: is this copy necessary? + PNG_error = PNG_convert(info, info->image, copy->data); + } + return info; +} + +/*************************************************************************************************/ + +#ifdef TEST + +#include +#include + +int main(int argc, char **argv) +{ + char *fname = (argc > 1) ? argv[1] : "test.png"; + PNG_info_t *info; + struct stat statbuf; + uint32_t insize, outsize; + FILE *infp, *outfp; + uint8_t *inbuf; + uint32_t n; + + if (stat(fname, &statbuf) != 0) { + perror("stat"); + return 1; + } else if (!statbuf.st_size) { + printf("file empty\n"); + return 1; + } + insize = (uint32_t) statbuf.st_size; + inbuf = malloc(insize); + infp = fopen(fname, "rb"); + if (!infp) { + perror("fopen"); + return 1; + } else if (fread(inbuf, 1, insize, infp) != insize) { + perror("fread"); + return 1; + } + fclose(infp); + + printf("input file: %s (size: %d)\n", fname, insize); + + info = PNG_decode(inbuf, insize); + free(inbuf); + printf("PNG_error: %d\n", PNG_error); + if (PNG_error != 0) + return 1; + + printf("width: %d, height: %d\nfirst 16 bytes: ", info->width, info->height); + for (n = 0; n < 16; n++) + printf("%02x ", info->image->data[n]); + printf("\n"); + + outsize = info->width * info->height * 4; + printf("image size: %d\n", outsize); + if (outsize != info->image->size) { + printf("error: image size doesn't match dimensions\n"); + return 1; + } + outfp = fopen("out.bin", "wb"); + if (!outfp) { + perror("fopen"); + return 1; + } else if (fwrite(info->image->data, 1, outsize, outfp) != outsize) { + perror("fwrite"); + return 1; + } + fclose(outfp); + +#ifdef ALLOC_DEBUG + png_alloc_node_t *node; + for (node = png_alloc_head, n = 1; node; node = node->next, n++) + printf("node %d (%p) addr = %p, size = %ld\n", n, node, node->addr, node->size); +#endif + png_alloc_free_all(); // also frees info and image data from PNG_decode + + return 0; +} + +#endif diff --git a/lib/gui/picopng.h b/lib/gui/picopng.h new file mode 100644 index 0000000..14c5e28 --- /dev/null +++ b/lib/gui/picopng.h @@ -0,0 +1,34 @@ +#ifndef _PICOPNG_H +#define _PICOPNG_H + +typedef struct { + uint32_t *data; + size_t size; + size_t allocsize; +} vector32_t; + +typedef struct { + uint8_t *data; + size_t size; + size_t allocsize; +} vector8_t; + +typedef struct { + uint32_t width, height; + uint32_t colorType, bitDepth; + uint32_t compressionMethod, filterMethod, interlaceMethod; + uint32_t key_r, key_g, key_b; + bool key_defined; // is a transparent color key given? + vector8_t *palette; + vector8_t *image; +} PNG_info_t; + +PNG_info_t *PNG_decode(const uint8_t *in, uint32_t size); +void png_alloc_free_all(void); + +unsigned picopng_zlib_decompress(unsigned char* out, size_t outsize, + const unsigned char* in, size_t insize); + +extern int PNG_error; + +#endif diff --git a/lib/gui/png.c b/lib/gui/png.c new file mode 100644 index 0000000..5d77c8c --- /dev/null +++ b/lib/gui/png.c @@ -0,0 +1,89 @@ +#include +#include +#include +#include +#include +#include +#include +#include +#include + +#include "png.h" + +z_stream png_stream; +static int initialized; + +int png_uncompress_init(void) +{ + if (!initialized++) { + png_stream.workspace = malloc(zlib_inflate_workspacesize()); + if (!png_stream.workspace) { + initialized = 0; + return -ENOMEM; + } + png_stream.next_in = NULL; + png_stream.avail_in = 0; + zlib_inflateInit(&png_stream); + } + return 0; +} + +void png_uncompress_exit(void) +{ + if (!--initialized) { + zlib_inflateEnd(&png_stream); + vfree(png_stream.workspace); + } +} + +static int png_renderer(struct fb_info *info, struct image *img, void* fb, + int startx, int starty, void* offscreenbuf) +{ + int width, height; + void *buf; + int xres, yres; + + xres = info->xres; + yres = info->yres; + + if (startx < 0) { + startx = (xres - img->width) / 2; + if (startx < 0) + startx = 0; + } + + if (starty < 0) { + starty = (yres - img->height) / 2; + if (starty < 0) + starty = 0; + } + + width = min(img->width, xres - startx); + height = min(img->height, yres - starty); + + buf = offscreenbuf ? offscreenbuf : fb; + + rgba_blend(info, img->data, buf, height, width, startx, starty, true); + + if (offscreenbuf) { + int fbsize; + + fbsize = xres * yres * (info->bits_per_pixel >> 3); + memcpy(fb, offscreenbuf, fbsize); + } + + return img->height; +} + +static struct image_renderer png = { + .type = filetype_png, + .open = png_open, + .close = png_close, + .renderer = png_renderer, +}; + +static int png_init(void) +{ + return image_renderer_register(&png); +} +fs_initcall(png_init); diff --git a/lib/gui/png.h b/lib/gui/png.h new file mode 100644 index 0000000..3ac9364 --- /dev/null +++ b/lib/gui/png.h @@ -0,0 +1,21 @@ +/* + * Copyright (C) 2012 Jean-Christophe PLAGNIOL-VILLARD + * + * GPL v2 + */ + +#ifndef __PNG_H__ +#define __PNG_H__ + +#include +#include +#include +#include + +int png_uncompress_init(void); +void png_uncompress_exit(void); +void png_close(struct image *img); +struct image *png_open(char *inbuf, int insize); +extern z_stream png_stream; + +#endif /* __PNG_H__ */ diff --git a/lib/gui/png_lode.c b/lib/gui/png_lode.c new file mode 100644 index 0000000..477704d --- /dev/null +++ b/lib/gui/png_lode.c @@ -0,0 +1,90 @@ +#include +#include +#include +#include +#include +#include +#include +#include +#include + +#include "lodepng.h" +#include "png.h" + +unsigned lodepng_custom_zlib_decompress(unsigned char** out, size_t* outsize, + const unsigned char* in, size_t insize, + const LodePNGDecompressSettings* settings) +{ + int err; + + png_stream.next_in = in; + png_stream.avail_in = insize; + + png_stream.next_out = *out; + png_stream.avail_out = *outsize; + + err = zlib_inflateReset(&png_stream); + if (err != Z_OK) { + printk("zlib_inflateReset error %d\n", err); + zlib_inflateEnd(&png_stream); + zlib_inflateInit(&png_stream); + } + + err = zlib_inflate(&png_stream, Z_FINISH); + if (err != Z_STREAM_END) + goto err; + return 0; + +err: + printk("Error %d while decompressing!\n", err); + printk("%p(%zd)->%p(%zd)\n", in, insize, *out, *outsize); + return -EIO; +} + +struct image *png_open(char *inbuf, int insize) +{ + LodePNGState state; + int ret; + unsigned error; + struct image *img = calloc(1, sizeof(struct image)); + unsigned char *png; + + if (!img) + return ERR_PTR(-ENOMEM); + + ret = png_uncompress_init(); + if (ret) + goto err; + + lodepng_state_init(&state); + + state.info_raw.colortype = LCT_RGBA; + state.info_raw.bitdepth = 8; + + error = lodepng_decode(&png, &img->width, &img->height, &state, inbuf, insize); + + if(error) { + printf("error %u: %s\n", error, lodepng_error_text(error)); + ret = -EINVAL; + goto err; + } + + img->bits_per_pixel = 4 << 3; + img->data = png; + + pr_debug("png: %d x %d data@0x%p\n", img->width, img->height, img->data); + + lodepng_state_cleanup(&state); + + return img; +err: + free(png); + free(img); + return ERR_PTR(ret); +} + +void png_close(struct image *img) +{ + free(img->data); + png_uncompress_exit(); +} diff --git a/lib/gui/png_pico.c b/lib/gui/png_pico.c new file mode 100644 index 0000000..393a732 --- /dev/null +++ b/lib/gui/png_pico.c @@ -0,0 +1,85 @@ +#include +#include +#include +#include +#include +#include +#include +#include +#include + +#include "picopng.h" +#include "png.h" + +unsigned picopng_zlib_decompress(unsigned char* out, size_t outsize, + const unsigned char* in, size_t insize) +{ + int err; + + png_stream.next_in = in; + png_stream.avail_in = insize; + + png_stream.next_out = out; + png_stream.avail_out = outsize; + + err = zlib_inflateReset(&png_stream); + if (err != Z_OK) { + printk("zlib_inflateReset error %d\n", err); + zlib_inflateEnd(&png_stream); + zlib_inflateInit(&png_stream); + } + + err = zlib_inflate(&png_stream, Z_FINISH); + if (err != Z_STREAM_END) + goto err; + return 0; + +err: + printk("Error %d while decompressing!\n", err); + printk("%p(%zd)->%p(%zd)\n", in, insize, out, outsize); + return -EIO; +} + +struct image *png_open(char *inbuf, int insize) +{ + PNG_info_t *png_info; + int ret; + struct image *img = calloc(1, sizeof(struct image)); + + if (!img) + return ERR_PTR(-ENOMEM); + + ret = png_uncompress_init(); + if (ret) + goto err; + + /* rgba */ + png_info = PNG_decode(inbuf, insize); + + if(PNG_error) { + printf("error %u:\n", PNG_error); + ret = -EINVAL; + goto err; + } + + img->width = png_info->width; + img->height = png_info->height; + img->bits_per_pixel = 4 << 3; + img->data = png_info->image->data; + + pr_debug("png: %d x %d data@0x%p\n", img->width, img->height, img->data); + + png_alloc_free_all(); + + return img; +err: + png_alloc_free_all(); + free(img); + return ERR_PTR(ret); +} + +void png_close(struct image *img) +{ + free(img->data); + png_alloc_free_all(); +} diff --git a/lib/image_renderer.c b/lib/image_renderer.c deleted file mode 100644 index fff35bd..0000000 --- a/lib/image_renderer.c +++ /dev/null @@ -1,96 +0,0 @@ -/* - * Copyright (C) 2012 Jean-Christophe PLAGNIOL-VILLARD - * - * GPL v2 - */ - -#include -#include -#include -#include -#include -#include - -static LIST_HEAD(image_renderers); - -static struct image_renderer *get_renderer(void* buf) -{ - struct image_renderer *ir; - enum filetype type = file_detect_type(buf); - - list_for_each_entry(ir, &image_renderers, list) { - if (ir->type == type) - return ir; - } - - return NULL; -} - -struct image *image_renderer_open(const char* file) -{ - void *data; - size_t size; - struct image_renderer *ir; - struct image *img; - int ret; - - data = read_file(file, &size); - if (!data) { - printf("unable to read %s\n", file); - return ERR_PTR(-ENOMEM); - } - - ir = get_renderer(data); - if (!ir) { - ret = -ENOENT; - goto out; - } - - img = ir->open(data, size); - if (IS_ERR(img)) { - ret = PTR_ERR(img); - goto out; - } - img->ir = ir; - if (!ir->keep_file_data) - free(data); - - return img; -out: - free(data); - return ERR_PTR(ret); -} - -void image_renderer_close(struct image *img) -{ - if (!img) - return; - - img->ir->close(img); - - free(img); -} - -int image_renderer_image(struct fb_info *info, struct image *img, void* fb, - int startx, int starty, void* offscreenbuf) -{ - return img->ir->renderer(info, img, fb, startx, starty, offscreenbuf); -} - -int image_renderer_register(struct image_renderer *ir) -{ - if (!ir || !ir->type || !ir->renderer || !ir->open || !ir->close) - return -EIO; - - list_add_tail(&ir->list, &image_renderers); - - return 0; -} - -void image_renderer_unregister(struct image_renderer *ir) -{ - if (!ir) - return; - - list_del(&ir->list); -} diff --git a/lib/lodepng.c b/lib/lodepng.c deleted file mode 100644 index ba21cd2..0000000 --- a/lib/lodepng.c +++ /dev/null @@ -1,5928 +0,0 @@ -/* -LodePNG version 20120729 - -Copyright (c) 2005-2012 Lode Vandevenne - -This software is provided 'as-is', without any express or implied -warranty. In no event will the authors be held liable for any damages -arising from the use of this software. - -Permission is granted to anyone to use this software for any purpose, -including commercial applications, and to alter it and redistribute it -freely, subject to the following restrictions: - - 1. The origin of this software must not be misrepresented; you must not - claim that you wrote the original software. If you use this software - in a product, an acknowledgment in the product documentation would be - appreciated but is not required. - - 2. Altered source versions must be plainly marked as such, and must not be - misrepresented as being the original software. - - 3. This notice may not be removed or altered from any source - distribution. -*/ - -/* -The manual and changelog are in the header file "lodepng.h" -Rename this file to lodepng.cpp to use it for C++, or to lodepng.c to use it for C. -*/ - -#include "lodepng.h" - -#include -#include - -#ifdef __BAREBOX__ -#include -#include -#include -#include -#endif - -#ifdef LODEPNG_COMPILE_CPP -#include -#endif /*LODEPNG_COMPILE_CPP*/ - -#define VERSION_STRING "20120729" - -/* -This source file is built up in the following large parts. The code sections -with the "LODEPNG_COMPILE_" #defines divide this up further in an intermixed way. --Tools for C and common code for PNG and Zlib --C Code for Zlib (huffman, deflate, ...) --C Code for PNG (file format chunks, adam7, PNG filters, color conversions, ...) --The C++ wrapper around all of the above -*/ - -/*The malloc, realloc and free functions defined here with "my" in front of the -name, so that you can easily change them to others related to your platform in -this one location if needed. Everything else in the code calls these.*/ - -static void* mymalloc(size_t size) -{ - return malloc(size); -} - -static void* myrealloc(void* ptr, size_t new_size) -{ - return realloc(ptr, new_size); -} - -static void myfree(void* ptr) -{ - free(ptr); -} - -/* -Declaration of the custom functions used if LODEPNG_COMPILE_ZLIB isn't defined -or LODEPNG_CUSTOM_ZLIB_DECODER or LODEPNG_CUSTOM_ZLIB_ENCODER are enabled. - -In that case, you need to define these yourself (which you can do in one of your -own source files) so that LodePNG can link to it. - -By default, this is not needed. If LODEPNG_COMPILE_ZLIB isn't defined, then only -the two zlib related ones are needed. - -If needed, the functions must act as follows: -*out must be NULL and *outsize must be 0 initially, and after the function is done, -*out must point to the decompressed data, *outsize must be the size of it, and must -be the size of the useful data in bytes, not the alloc size. -*/ -unsigned lodepng_custom_zlib_decompress(unsigned char** out, size_t* outsize, - const unsigned char* in, size_t insize, - const LodePNGDecompressSettings* settings); -unsigned lodepng_custom_zlib_compress(unsigned char** out, size_t* outsize, - const unsigned char* in, size_t insize, - const LodePNGCompressSettings* settings); -unsigned lodepng_custom_inflate(unsigned char** out, size_t* outsize, - const unsigned char* in, size_t insize, - const LodePNGDecompressSettings* settings); -unsigned lodepng_custom_deflate(unsigned char** out, size_t* outsize, - const unsigned char* in, size_t insize, - const LodePNGCompressSettings* settings); - -/* ////////////////////////////////////////////////////////////////////////// */ -/* ////////////////////////////////////////////////////////////////////////// */ -/* // Tools for C, and common code for PNG and Zlib. // */ -/* ////////////////////////////////////////////////////////////////////////// */ -/* ////////////////////////////////////////////////////////////////////////// */ - -/* -Often in case of an error a value is assigned to a variable and then it breaks -out of a loop (to go to the cleanup phase of a function). This macro does that. -It makes the error handling code shorter and more readable. - -Example: if(!uivector_resizev(&frequencies_ll, 286, 0)) ERROR_BREAK(83); -*/ -#define CERROR_BREAK(errorvar, code)\ -{\ - errorvar = code;\ - break;\ -} - -/*version of CERROR_BREAK that assumes the common case where the error variable is named "error"*/ -#define ERROR_BREAK(code) CERROR_BREAK(error, code) - -/*Set error var to the error code, and return it.*/ -#define CERROR_RETURN_ERROR(errorvar, code)\ -{\ - errorvar = code;\ - return code;\ -} - -/*Try the code, if it returns error, also return the error.*/ -#define CERROR_TRY_RETURN(call)\ -{\ - unsigned error = call;\ - if(error) return error;\ -} - -/* -About uivector, ucvector and string: --All of them wrap dynamic arrays or text strings in a similar way. --LodePNG was originally written in C++. The vectors replace the std::vectors that were used in the C++ version. --The string tools are made to avoid problems with compilers that declare things like strncat as deprecated. --They're not used in the interface, only internally in this file as static functions. --As with many other structs in this file, the init and cleanup functions serve as ctor and dtor. -*/ - -#ifdef LODEPNG_COMPILE_ZLIB -/*dynamic vector of unsigned ints*/ -typedef struct uivector -{ - unsigned* data; - size_t size; /*size in number of unsigned longs*/ - size_t allocsize; /*allocated size in bytes*/ -} uivector; - -static void uivector_cleanup(void* p) -{ - ((uivector*)p)->size = ((uivector*)p)->allocsize = 0; - myfree(((uivector*)p)->data); - ((uivector*)p)->data = NULL; -} - -/*returns 1 if success, 0 if failure ==> nothing done*/ -static unsigned uivector_resize(uivector* p, size_t size) -{ - if(size * sizeof(unsigned) > p->allocsize) - { - size_t newsize = size * sizeof(unsigned) * 2; - void* data = myrealloc(p->data, newsize); - if(data) - { - p->allocsize = newsize; - p->data = (unsigned*)data; - p->size = size; - } - else return 0; - } - else p->size = size; - return 1; -} - -/*resize and give all new elements the value*/ -static unsigned uivector_resizev(uivector* p, size_t size, unsigned value) -{ - size_t oldsize = p->size, i; - if(!uivector_resize(p, size)) return 0; - for(i = oldsize; i < size; i++) p->data[i] = value; - return 1; -} - -static void uivector_init(uivector* p) -{ - p->data = NULL; - p->size = p->allocsize = 0; -} - -#ifdef LODEPNG_COMPILE_ENCODER -/*returns 1 if success, 0 if failure ==> nothing done*/ -static unsigned uivector_push_back(uivector* p, unsigned c) -{ - if(!uivector_resize(p, p->size + 1)) return 0; - p->data[p->size - 1] = c; - return 1; -} - -/*copy q to p, returns 1 if success, 0 if failure ==> nothing done*/ -static unsigned uivector_copy(uivector* p, const uivector* q) -{ - size_t i; - if(!uivector_resize(p, q->size)) return 0; - for(i = 0; i < q->size; i++) p->data[i] = q->data[i]; - return 1; -} - -static void uivector_swap(uivector* p, uivector* q) -{ - size_t tmp; - unsigned* tmpp; - tmp = p->size; p->size = q->size; q->size = tmp; - tmp = p->allocsize; p->allocsize = q->allocsize; q->allocsize = tmp; - tmpp = p->data; p->data = q->data; q->data = tmpp; -} -#endif /*LODEPNG_COMPILE_ENCODER*/ -#endif /*LODEPNG_COMPILE_ZLIB*/ - -/* /////////////////////////////////////////////////////////////////////////// */ - -/*dynamic vector of unsigned chars*/ -typedef struct ucvector -{ - unsigned char* data; - size_t size; /*used size*/ - size_t allocsize; /*allocated size*/ -} ucvector; - -static void ucvector_cleanup(void* p) -{ - ((ucvector*)p)->size = ((ucvector*)p)->allocsize = 0; - myfree(((ucvector*)p)->data); - ((ucvector*)p)->data = NULL; -} - -/*returns 1 if success, 0 if failure ==> nothing done*/ -static unsigned ucvector_resize(ucvector* p, size_t size) -{ - if(size * sizeof(unsigned char) > p->allocsize) - { - size_t newsize = size * sizeof(unsigned char) * 2; - void* data = myrealloc(p->data, newsize); - if(data) - { - p->allocsize = newsize; - p->data = (unsigned char*)data; - p->size = size; - } - else return 0; /*error: not enough memory*/ - } - else p->size = size; - return 1; -} - -#ifdef LODEPNG_COMPILE_DECODER -#ifdef LODEPNG_COMPILE_PNG -/*resize and give all new elements the value*/ -static unsigned ucvector_resizev(ucvector* p, size_t size, unsigned char value) -{ - size_t oldsize = p->size, i; - if(!ucvector_resize(p, size)) return 0; - for(i = oldsize; i < size; i++) p->data[i] = value; - return 1; -} -#endif /*LODEPNG_COMPILE_PNG*/ -#endif /*LODEPNG_COMPILE_DECODER*/ - -static void ucvector_init(ucvector* p) -{ - p->data = NULL; - p->size = p->allocsize = 0; -} - -#ifdef LODEPNG_COMPILE_ZLIB -/*you can both convert from vector to buffer&size and vica versa. If you use -init_buffer to take over a buffer and size, it is not needed to use cleanup*/ -static void ucvector_init_buffer(ucvector* p, unsigned char* buffer, size_t size) -{ - p->data = buffer; - p->allocsize = p->size = size; -} -#endif /*LODEPNG_COMPILE_ZLIB*/ - -#ifdef LODEPNG_COMPILE_ENCODER -/*returns 1 if success, 0 if failure ==> nothing done*/ -static unsigned ucvector_push_back(ucvector* p, unsigned char c) -{ - if(!ucvector_resize(p, p->size + 1)) return 0; - p->data[p->size - 1] = c; - return 1; -} -#endif /*LODEPNG_COMPILE_ENCODER*/ - - -/* ////////////////////////////////////////////////////////////////////////// */ - -#ifdef LODEPNG_COMPILE_PNG -#ifdef LODEPNG_COMPILE_ANCILLARY_CHUNKS -/*returns 1 if success, 0 if failure ==> nothing done*/ -static unsigned string_resize(char** out, size_t size) -{ - char* data = (char*)myrealloc(*out, size + 1); - if(data) - { - data[size] = 0; /*null termination char*/ - *out = data; - } - return data != 0; -} - -/*init a {char*, size_t} pair for use as string*/ -static void string_init(char** out) -{ - *out = NULL; - string_resize(out, 0); -} - -/*free the above pair again*/ -static void string_cleanup(char** out) -{ - myfree(*out); - *out = NULL; -} - -static void string_set(char** out, const char* in) -{ - size_t insize = strlen(in), i = 0; - if(string_resize(out, insize)) - { - for(i = 0; i < insize; i++) - { - (*out)[i] = in[i]; - } - } -} -#endif /*LODEPNG_COMPILE_ANCILLARY_CHUNKS*/ -#endif /*LODEPNG_COMPILE_PNG*/ - -/* ////////////////////////////////////////////////////////////////////////// */ - -unsigned lodepng_read32bitInt(const unsigned char* buffer) -{ - return (buffer[0] << 24) | (buffer[1] << 16) | (buffer[2] << 8) | buffer[3]; -} - -/*buffer must have at least 4 allocated bytes available*/ -static void lodepng_set32bitInt(unsigned char* buffer, unsigned value) -{ - buffer[0] = (unsigned char)((value >> 24) & 0xff); - buffer[1] = (unsigned char)((value >> 16) & 0xff); - buffer[2] = (unsigned char)((value >> 8) & 0xff); - buffer[3] = (unsigned char)((value ) & 0xff); -} - -#ifdef LODEPNG_COMPILE_ENCODER -static void lodepng_add32bitInt(ucvector* buffer, unsigned value) -{ - ucvector_resize(buffer, buffer->size + 4); /*todo: give error if resize failed*/ - lodepng_set32bitInt(&buffer->data[buffer->size - 4], value); -} -#endif /*LODEPNG_COMPILE_ENCODER*/ - -/* ////////////////////////////////////////////////////////////////////////// */ -/* / File IO / */ -/* ////////////////////////////////////////////////////////////////////////// */ - -#ifdef LODEPNG_COMPILE_DISK - -unsigned lodepng_load_file(unsigned char** out, size_t* outsize, const char* filename) -{ - FILE* file; - long size; - - /*provide some proper output values if error will happen*/ - *out = 0; - *outsize = 0; - - file = fopen(filename, "rb"); - if(!file) return 78; - - /*get filesize:*/ - fseek(file , 0 , SEEK_END); - size = ftell(file); - rewind(file); - - /*read contents of the file into the vector*/ - *outsize = 0; - *out = (unsigned char*)mymalloc((size_t)size); - if(size && (*out)) (*outsize) = fread(*out, 1, (size_t)size, file); - - fclose(file); - if(!(*out) && size) return 83; /*the above malloc failed*/ - return 0; -} - -/*write given buffer to the file, overwriting the file, it doesn't append to it.*/ -unsigned lodepng_save_file(const unsigned char* buffer, size_t buffersize, const char* filename) -{ - FILE* file; - file = fopen(filename, "wb" ); - if(!file) return 79; - fwrite((char*)buffer , 1 , buffersize, file); - fclose(file); - return 0; -} - -#endif /*LODEPNG_COMPILE_DISK*/ - -/* ////////////////////////////////////////////////////////////////////////// */ -/* ////////////////////////////////////////////////////////////////////////// */ -/* // End of common code and tools. Begin of Zlib related code. // */ -/* ////////////////////////////////////////////////////////////////////////// */ -/* ////////////////////////////////////////////////////////////////////////// */ - -#ifdef LODEPNG_COMPILE_ZLIB -#ifdef LODEPNG_COMPILE_ENCODER -/*TODO: this ignores potential out of memory errors*/ -static void addBitToStream(size_t* bitpointer, ucvector* bitstream, unsigned char bit) -{ - /*add a new byte at the end*/ - if((*bitpointer) % 8 == 0) ucvector_push_back(bitstream, (unsigned char)0); - /*earlier bit of huffman code is in a lesser significant bit of an earlier byte*/ - (bitstream->data[bitstream->size - 1]) |= (bit << ((*bitpointer) & 0x7)); - (*bitpointer)++; -} - -static void addBitsToStream(size_t* bitpointer, ucvector* bitstream, unsigned value, size_t nbits) -{ - size_t i; - for(i = 0; i < nbits; i++) addBitToStream(bitpointer, bitstream, (unsigned char)((value >> i) & 1)); -} - -static void addBitsToStreamReversed(size_t* bitpointer, ucvector* bitstream, unsigned value, size_t nbits) -{ - size_t i; - for(i = 0; i < nbits; i++) addBitToStream(bitpointer, bitstream, (unsigned char)((value >> (nbits - 1 - i)) & 1)); -} -#endif /*LODEPNG_COMPILE_ENCODER*/ - -#ifdef LODEPNG_COMPILE_DECODER - -#define READBIT(bitpointer, bitstream) ((bitstream[bitpointer >> 3] >> (bitpointer & 0x7)) & (unsigned char)1) - -static unsigned char readBitFromStream(size_t* bitpointer, const unsigned char* bitstream) -{ - unsigned char result = (unsigned char)(READBIT(*bitpointer, bitstream)); - (*bitpointer)++; - return result; -} - -static unsigned readBitsFromStream(size_t* bitpointer, const unsigned char* bitstream, size_t nbits) -{ - unsigned result = 0, i; - for(i = 0; i < nbits; i++) - { - result += ((unsigned)READBIT(*bitpointer, bitstream)) << i; - (*bitpointer)++; - } - return result; -} -#endif /*LODEPNG_COMPILE_DECODER*/ - -/* ////////////////////////////////////////////////////////////////////////// */ -/* / Deflate - Huffman / */ -/* ////////////////////////////////////////////////////////////////////////// */ - -#define FIRST_LENGTH_CODE_INDEX 257 -#define LAST_LENGTH_CODE_INDEX 285 -/*256 literals, the end code, some length codes, and 2 unused codes*/ -#define NUM_DEFLATE_CODE_SYMBOLS 288 -/*the distance codes have their own symbols, 30 used, 2 unused*/ -#define NUM_DISTANCE_SYMBOLS 32 -/*the code length codes. 0-15: code lengths, 16: copy previous 3-6 times, 17: 3-10 zeros, 18: 11-138 zeros*/ -#define NUM_CODE_LENGTH_CODES 19 - -/*the base lengths represented by codes 257-285*/ -static const unsigned LENGTHBASE[29] - = {3, 4, 5, 6, 7, 8, 9, 10, 11, 13, 15, 17, 19, 23, 27, 31, 35, 43, 51, 59, - 67, 83, 99, 115, 131, 163, 195, 227, 258}; - -/*the extra bits used by codes 257-285 (added to base length)*/ -static const unsigned LENGTHEXTRA[29] - = {0, 0, 0, 0, 0, 0, 0, 0, 1, 1, 1, 1, 2, 2, 2, 2, 3, 3, 3, 3, - 4, 4, 4, 4, 5, 5, 5, 5, 0}; - -/*the base backwards distances (the bits of distance codes appear after length codes and use their own huffman tree)*/ -static const unsigned DISTANCEBASE[30] - = {1, 2, 3, 4, 5, 7, 9, 13, 17, 25, 33, 49, 65, 97, 129, 193, 257, 385, 513, - 769, 1025, 1537, 2049, 3073, 4097, 6145, 8193, 12289, 16385, 24577}; - -/*the extra bits of backwards distances (added to base)*/ -static const unsigned DISTANCEEXTRA[30] - = {0, 0, 0, 0, 1, 1, 2, 2, 3, 3, 4, 4, 5, 5, 6, 6, 7, 7, 8, - 8, 9, 9, 10, 10, 11, 11, 12, 12, 13, 13}; - -/*the order in which "code length alphabet code lengths" are stored, out of this -the huffman tree of the dynamic huffman tree lengths is generated*/ -static const unsigned CLCL_ORDER[NUM_CODE_LENGTH_CODES] - = {16, 17, 18, 0, 8, 7, 9, 6, 10, 5, 11, 4, 12, 3, 13, 2, 14, 1, 15}; - -/* ////////////////////////////////////////////////////////////////////////// */ - -/* -Huffman tree struct, containing multiple representations of the tree -*/ -typedef struct HuffmanTree -{ - unsigned* tree2d; - unsigned* tree1d; - unsigned* lengths; /*the lengths of the codes of the 1d-tree*/ - unsigned maxbitlen; /*maximum number of bits a single code can get*/ - unsigned numcodes; /*number of symbols in the alphabet = number of codes*/ -} HuffmanTree; - -/*function used for debug purposes to draw the tree in ascii art with C++*/ -/*#include -static void HuffmanTree_draw(HuffmanTree* tree) -{ - std::cout << "tree. length: " << tree->numcodes << " maxbitlen: " << tree->maxbitlen << std::endl; - for(size_t i = 0; i < tree->tree1d.size; i++) - { - if(tree->lengths.data[i]) - std::cout << i << " " << tree->tree1d.data[i] << " " << tree->lengths.data[i] << std::endl; - } - std::cout << std::endl; -}*/ - -static void HuffmanTree_init(HuffmanTree* tree) -{ - tree->tree2d = 0; - tree->tree1d = 0; - tree->lengths = 0; -} - -static void HuffmanTree_cleanup(HuffmanTree* tree) -{ - myfree(tree->tree2d); - myfree(tree->tree1d); - myfree(tree->lengths); -} - -/*the tree representation used by the decoder. return value is error*/ -static unsigned HuffmanTree_make2DTree(HuffmanTree* tree) -{ - unsigned nodefilled = 0; /*up to which node it is filled*/ - unsigned treepos = 0; /*position in the tree (1 of the numcodes columns)*/ - unsigned n, i; - - tree->tree2d = (unsigned*)mymalloc(tree->numcodes * 2 * sizeof(unsigned)); - if(!tree->tree2d) return 83; /*alloc fail*/ - - /* - convert tree1d[] to tree2d[][]. In the 2D array, a value of 32767 means - uninited, a value >= numcodes is an address to another bit, a value < numcodes - is a code. The 2 rows are the 2 possible bit values (0 or 1), there are as - many columns as codes - 1. - A good huffmann tree has N * 2 - 1 nodes, of which N - 1 are internal nodes. - Here, the internal nodes are stored (what their 0 and 1 option point to). - There is only memory for such good tree currently, if there are more nodes - (due to too long length codes), error 55 will happen - */ - for(n = 0; n < tree->numcodes * 2; n++) - { - tree->tree2d[n] = 32767; /*32767 here means the tree2d isn't filled there yet*/ - } - - for(n = 0; n < tree->numcodes; n++) /*the codes*/ - { - for(i = 0; i < tree->lengths[n]; i++) /*the bits for this code*/ - { - unsigned char bit = (unsigned char)((tree->tree1d[n] >> (tree->lengths[n] - i - 1)) & 1); - if(treepos > tree->numcodes - 2) return 55; /*oversubscribed, see comment in lodepng_error_text*/ - if(tree->tree2d[2 * treepos + bit] == 32767) /*not yet filled in*/ - { - if(i + 1 == tree->lengths[n]) /*last bit*/ - { - tree->tree2d[2 * treepos + bit] = n; /*put the current code in it*/ - treepos = 0; - } - else - { - /*put address of the next step in here, first that address has to be found of course - (it's just nodefilled + 1)...*/ - nodefilled++; - /*addresses encoded with numcodes added to it*/ - tree->tree2d[2 * treepos + bit] = nodefilled + tree->numcodes; - treepos = nodefilled; - } - } - else treepos = tree->tree2d[2 * treepos + bit] - tree->numcodes; - } - } - - for(n = 0; n < tree->numcodes * 2; n++) - { - if(tree->tree2d[n] == 32767) tree->tree2d[n] = 0; /*remove possible remaining 32767's*/ - } - - return 0; -} - -/* -Second step for the ...makeFromLengths and ...makeFromFrequencies functions. -numcodes, lengths and maxbitlen must already be filled in correctly. return -value is error. -*/ -static unsigned HuffmanTree_makeFromLengths2(HuffmanTree* tree) -{ - uivector blcount; - uivector nextcode; - unsigned bits, n, error = 0; - - uivector_init(&blcount); - uivector_init(&nextcode); - - tree->tree1d = (unsigned*)mymalloc(tree->numcodes * sizeof(unsigned)); - if(!tree->tree1d) error = 83; /*alloc fail*/ - - if(!uivector_resizev(&blcount, tree->maxbitlen + 1, 0) - || !uivector_resizev(&nextcode, tree->maxbitlen + 1, 0)) - error = 83; /*alloc fail*/ - - if(!error) - { - /*step 1: count number of instances of each code length*/ - for(bits = 0; bits < tree->numcodes; bits++) blcount.data[tree->lengths[bits]]++; - /*step 2: generate the nextcode values*/ - for(bits = 1; bits <= tree->maxbitlen; bits++) - { - nextcode.data[bits] = (nextcode.data[bits - 1] + blcount.data[bits - 1]) << 1; - } - /*step 3: generate all the codes*/ - for(n = 0; n < tree->numcodes; n++) - { - if(tree->lengths[n] != 0) tree->tree1d[n] = nextcode.data[tree->lengths[n]]++; - } - } - - uivector_cleanup(&blcount); - uivector_cleanup(&nextcode); - - if(!error) return HuffmanTree_make2DTree(tree); - else return error; -} - -/* -given the code lengths (as stored in the PNG file), generate the tree as defined -by Deflate. maxbitlen is the maximum bits that a code in the tree can have. -return value is error. -*/ -static unsigned HuffmanTree_makeFromLengths(HuffmanTree* tree, const unsigned* bitlen, - size_t numcodes, unsigned maxbitlen) -{ - unsigned i; - tree->lengths = (unsigned*)mymalloc(numcodes * sizeof(unsigned)); - if(!tree->lengths) return 83; /*alloc fail*/ - for(i = 0; i < numcodes; i++) tree->lengths[i] = bitlen[i]; - tree->numcodes = (unsigned)numcodes; /*number of symbols*/ - tree->maxbitlen = maxbitlen; - return HuffmanTree_makeFromLengths2(tree); -} - -#ifdef LODEPNG_COMPILE_ENCODER - -/* -A coin, this is the terminology used for the package-merge algorithm and the -coin collector's problem. This is used to generate the huffman tree. -A coin can be multiple coins (when they're merged) -*/ -typedef struct Coin -{ - uivector symbols; - float weight; /*the sum of all weights in this coin*/ -} Coin; - -static void coin_init(Coin* c) -{ - uivector_init(&c->symbols); -} - -/*argument c is void* so that this dtor can be given as function pointer to the vector resize function*/ -static void coin_cleanup(void* c) -{ - uivector_cleanup(&((Coin*)c)->symbols); -} - -static void coin_copy(Coin* c1, const Coin* c2) -{ - c1->weight = c2->weight; - uivector_copy(&c1->symbols, &c2->symbols); -} - -static void add_coins(Coin* c1, const Coin* c2) -{ - size_t i; - for(i = 0; i < c2->symbols.size; i++) uivector_push_back(&c1->symbols, c2->symbols.data[i]); - c1->weight += c2->weight; -} - -static void init_coins(Coin* coins, size_t num) -{ - size_t i; - for(i = 0; i < num; i++) coin_init(&coins[i]); -} - -static void cleanup_coins(Coin* coins, size_t num) -{ - size_t i; - for(i = 0; i < num; i++) coin_cleanup(&coins[i]); -} - -/* -This uses a simple combsort to sort the data. This function is not critical for -overall encoding speed and the data amount isn't that large. -*/ -static void sort_coins(Coin* data, size_t amount) -{ - size_t gap = amount; - unsigned char swapped = 0; - while((gap > 1) || swapped) - { - size_t i; - gap = (gap * 10) / 13; /*shrink factor 1.3*/ - if(gap == 9 || gap == 10) gap = 11; /*combsort11*/ - if(gap < 1) gap = 1; - swapped = 0; - for(i = 0; i < amount - gap; i++) - { - size_t j = i + gap; - if(data[j].weight < data[i].weight) - { - float temp = data[j].weight; data[j].weight = data[i].weight; data[i].weight = temp; - uivector_swap(&data[i].symbols, &data[j].symbols); - swapped = 1; - } - } - } -} - -static unsigned append_symbol_coins(Coin* coins, const unsigned* frequencies, unsigned numcodes, size_t sum) -{ - unsigned i; - unsigned j = 0; /*index of present symbols*/ - for(i = 0; i < numcodes; i++) - { - if(frequencies[i] != 0) /*only include symbols that are present*/ - { - coins[j].weight = frequencies[i] / (float)sum; - uivector_push_back(&coins[j].symbols, i); - j++; - } - } - return 0; -} - -unsigned lodepng_huffman_code_lengths(unsigned* lengths, const unsigned* frequencies, - size_t numcodes, unsigned maxbitlen) -{ - unsigned i, j; - size_t sum = 0, numpresent = 0; - unsigned error = 0; - Coin* coins; /*the coins of the currently calculated row*/ - Coin* prev_row; /*the previous row of coins*/ - unsigned numcoins; - unsigned coinmem; - - if(numcodes == 0) return 80; /*error: a tree of 0 symbols is not supposed to be made*/ - - for(i = 0; i < numcodes; i++) - { - if(frequencies[i] > 0) - { - numpresent++; - sum += frequencies[i]; - } - } - - for(i = 0; i < numcodes; i++) lengths[i] = 0; - - /*there are no symbols at all, in that case add one symbol of value 0 to the tree (see RFC 1951 section 3.2.7) */ - if(numpresent == 0) - { - lengths[0] = 1; - } - /*the package merge algorithm gives wrong results if there's only one symbol - (theoretically 0 bits would then suffice, but we need a proper symbol for zlib)*/ - else if(numpresent == 1) - { - for(i = 0; i < numcodes; i++) if(frequencies[i]) lengths[i] = 1; - } - else - { - /*Package-Merge algorithm represented by coin collector's problem - For every symbol, maxbitlen coins will be created*/ - - coinmem = numpresent * 2; /*max amount of coins needed with the current algo*/ - coins = (Coin*)mymalloc(sizeof(Coin) * coinmem); - prev_row = (Coin*)mymalloc(sizeof(Coin) * coinmem); - if(!coins || !prev_row) return 83; /*alloc fail*/ - init_coins(coins, coinmem); - init_coins(prev_row, coinmem); - - /*first row, lowest denominator*/ - error = append_symbol_coins(coins, frequencies, numcodes, sum); - numcoins = numpresent; - sort_coins(coins, numcoins); - if(!error) - { - unsigned numprev = 0; - for(j = 1; j <= maxbitlen && !error; j++) /*each of the remaining rows*/ - { - unsigned tempnum; - Coin* tempcoins; - /*swap prev_row and coins, and their amounts*/ - tempcoins = prev_row; prev_row = coins; coins = tempcoins; - tempnum = numprev; numprev = numcoins; numcoins = tempnum; - - cleanup_coins(coins, numcoins); - init_coins(coins, numcoins); - - numcoins = 0; - - /*fill in the merged coins of the previous row*/ - for(i = 0; i + 1 < numprev; i += 2) - { - /*merge prev_row[i] and prev_row[i + 1] into new coin*/ - Coin* coin = &coins[numcoins++]; - coin_copy(coin, &prev_row[i]); - add_coins(coin, &prev_row[i + 1]); - } - /*fill in all the original symbols again*/ - if(j < maxbitlen) - { - error = append_symbol_coins(coins + numcoins, frequencies, numcodes, sum); - numcoins += numpresent; - } - sort_coins(coins, numcoins); - } - } - - if(!error) - { - /*calculate the lenghts of each symbol, as the amount of times a coin of each symbol is used*/ - for(i = 0; i < numpresent - 1; i++) - { - Coin* coin = &coins[i]; - for(j = 0; j < coin->symbols.size; j++) lengths[coin->symbols.data[j]]++; - } - } - - cleanup_coins(coins, coinmem); - myfree(coins); - cleanup_coins(prev_row, coinmem); - myfree(prev_row); - } - - return error; -} - -/*Create the Huffman tree given the symbol frequencies*/ -static unsigned HuffmanTree_makeFromFrequencies(HuffmanTree* tree, const unsigned* frequencies, - size_t numcodes, unsigned maxbitlen) -{ - unsigned error = 0; - tree->maxbitlen = maxbitlen; - tree->numcodes = (unsigned)numcodes; /*number of symbols*/ - tree->lengths = (unsigned*)myrealloc(tree->lengths, numcodes * sizeof(unsigned)); - if(!tree->lengths) return 83; /*alloc fail*/ - /*initialize all lengths to 0*/ - memset(tree->lengths, 0, numcodes * sizeof(unsigned)); - - error = lodepng_huffman_code_lengths(tree->lengths, frequencies, numcodes, maxbitlen); - if(!error) error = HuffmanTree_makeFromLengths2(tree); - return error; -} - -static unsigned HuffmanTree_getCode(const HuffmanTree* tree, unsigned index) -{ - return tree->tree1d[index]; -} - -static unsigned HuffmanTree_getLength(const HuffmanTree* tree, unsigned index) -{ - return tree->lengths[index]; -} -#endif /*LODEPNG_COMPILE_ENCODER*/ - -/*get the literal and length code tree of a deflated block with fixed tree, as per the deflate specification*/ -static unsigned generateFixedLitLenTree(HuffmanTree* tree) -{ - unsigned i, error = 0; - unsigned* bitlen = (unsigned*)mymalloc(NUM_DEFLATE_CODE_SYMBOLS * sizeof(unsigned)); - if(!bitlen) return 83; /*alloc fail*/ - - /*288 possible codes: 0-255=literals, 256=endcode, 257-285=lengthcodes, 286-287=unused*/ - for(i = 0; i <= 143; i++) bitlen[i] = 8; - for(i = 144; i <= 255; i++) bitlen[i] = 9; - for(i = 256; i <= 279; i++) bitlen[i] = 7; - for(i = 280; i <= 287; i++) bitlen[i] = 8; - - error = HuffmanTree_makeFromLengths(tree, bitlen, NUM_DEFLATE_CODE_SYMBOLS, 15); - - myfree(bitlen); - return error; -} - -/*get the distance code tree of a deflated block with fixed tree, as specified in the deflate specification*/ -static unsigned generateFixedDistanceTree(HuffmanTree* tree) -{ - unsigned i, error = 0; - unsigned* bitlen = (unsigned*)mymalloc(NUM_DISTANCE_SYMBOLS * sizeof(unsigned)); - if(!bitlen) return 83; /*alloc fail*/ - - /*there are 32 distance codes, but 30-31 are unused*/ - for(i = 0; i < NUM_DISTANCE_SYMBOLS; i++) bitlen[i] = 5; - error = HuffmanTree_makeFromLengths(tree, bitlen, NUM_DISTANCE_SYMBOLS, 15); - - myfree(bitlen); - return error; -} - -#ifdef LODEPNG_COMPILE_DECODER - -/* -returns the code, or (unsigned)(-1) if error happened -inbitlength is the length of the complete buffer, in bits (so its byte length times 8) -*/ -static unsigned huffmanDecodeSymbol(const unsigned char* in, size_t* bp, - const HuffmanTree* codetree, size_t inbitlength) -{ - unsigned treepos = 0, ct; - for(;;) - { - if(*bp >= inbitlength) return (unsigned)(-1); /*error: end of input memory reached without endcode*/ - /* - decode the symbol from the tree. The "readBitFromStream" code is inlined in - the expression below because this is the biggest bottleneck while decoding - */ - ct = codetree->tree2d[(treepos << 1) + READBIT(*bp, in)]; - (*bp)++; - if(ct < codetree->numcodes) return ct; /*the symbol is decoded, return it*/ - else treepos = ct - codetree->numcodes; /*symbol not yet decoded, instead move tree position*/ - - if(treepos >= codetree->numcodes) return (unsigned)(-1); /*error: it appeared outside the codetree*/ - } -} -#endif /*LODEPNG_COMPILE_DECODER*/ - -#ifdef LODEPNG_COMPILE_DECODER - -/* ////////////////////////////////////////////////////////////////////////// */ -/* / Inflator (Decompressor) / */ -/* ////////////////////////////////////////////////////////////////////////// */ - -/*get the tree of a deflated block with fixed tree, as specified in the deflate specification*/ -static void getTreeInflateFixed(HuffmanTree* tree_ll, HuffmanTree* tree_d) -{ - /*TODO: check for out of memory errors*/ - generateFixedLitLenTree(tree_ll); - generateFixedDistanceTree(tree_d); -} - -/*get the tree of a deflated block with dynamic tree, the tree itself is also Huffman compressed with a known tree*/ -static unsigned getTreeInflateDynamic(HuffmanTree* tree_ll, HuffmanTree* tree_d, - const unsigned char* in, size_t* bp, size_t inlength) -{ - /*make sure that length values that aren't filled in will be 0, or a wrong tree will be generated*/ - unsigned error = 0; - unsigned n, HLIT, HDIST, HCLEN, i; - size_t inbitlength = inlength * 8; - - /*see comments in deflateDynamic for explanation of the context and these variables, it is analogous*/ - unsigned* bitlen_ll = 0; /*lit,len code lengths*/ - unsigned* bitlen_d = 0; /*dist code lengths*/ - /*code length code lengths ("clcl"), the bit lengths of the huffman tree used to compress bitlen_ll and bitlen_d*/ - unsigned* bitlen_cl = 0; - HuffmanTree tree_cl; /*the code tree for code length codes (the huffman tree for compressed huffman trees)*/ - - if((*bp) >> 3 >= inlength - 2) return 49; /*error: the bit pointer is or will go past the memory*/ - - /*number of literal/length codes + 257. Unlike the spec, the value 257 is added to it here already*/ - HLIT = readBitsFromStream(bp, in, 5) + 257; - /*number of distance codes. Unlike the spec, the value 1 is added to it here already*/ - HDIST = readBitsFromStream(bp, in, 5) + 1; - /*number of code length codes. Unlike the spec, the value 4 is added to it here already*/ - HCLEN = readBitsFromStream(bp, in, 4) + 4; - - HuffmanTree_init(&tree_cl); - - while(!error) - { - /*read the code length codes out of 3 * (amount of code length codes) bits*/ - - bitlen_cl = (unsigned*)mymalloc(NUM_CODE_LENGTH_CODES * sizeof(unsigned)); - if(!bitlen_cl) ERROR_BREAK(83 /*alloc fail*/); - - for(i = 0; i < NUM_CODE_LENGTH_CODES; i++) - { - if(i < HCLEN) bitlen_cl[CLCL_ORDER[i]] = readBitsFromStream(bp, in, 3); - else bitlen_cl[CLCL_ORDER[i]] = 0; /*if not, it must stay 0*/ - } - - error = HuffmanTree_makeFromLengths(&tree_cl, bitlen_cl, NUM_CODE_LENGTH_CODES, 7); - if(error) break; - - /*now we can use this tree to read the lengths for the tree that this function will return*/ - bitlen_ll = (unsigned*)mymalloc(NUM_DEFLATE_CODE_SYMBOLS * sizeof(unsigned)); - bitlen_d = (unsigned*)mymalloc(NUM_DISTANCE_SYMBOLS * sizeof(unsigned)); - if(!bitlen_ll || !bitlen_d) ERROR_BREAK(83 /*alloc fail*/); - for(i = 0; i < NUM_DEFLATE_CODE_SYMBOLS; i++) bitlen_ll[i] = 0; - for(i = 0; i < NUM_DISTANCE_SYMBOLS; i++) bitlen_d[i] = 0; - - /*i is the current symbol we're reading in the part that contains the code lengths of lit/len and dist codes*/ - i = 0; - while(i < HLIT + HDIST) - { - unsigned code = huffmanDecodeSymbol(in, bp, &tree_cl, inbitlength); - if(code <= 15) /*a length code*/ - { - if(i < HLIT) bitlen_ll[i] = code; - else bitlen_d[i - HLIT] = code; - i++; - } - else if(code == 16) /*repeat previous*/ - { - unsigned replength = 3; /*read in the 2 bits that indicate repeat length (3-6)*/ - unsigned value; /*set value to the previous code*/ - - if(*bp >= inbitlength) ERROR_BREAK(50); /*error, bit pointer jumps past memory*/ - if (i == 0) ERROR_BREAK(54); /*can't repeat previous if i is 0*/ - - replength += readBitsFromStream(bp, in, 2); - - if(i < HLIT + 1) value = bitlen_ll[i - 1]; - else value = bitlen_d[i - HLIT - 1]; - /*repeat this value in the next lengths*/ - for(n = 0; n < replength; n++) - { - if(i >= HLIT + HDIST) ERROR_BREAK(13); /*error: i is larger than the amount of codes*/ - if(i < HLIT) bitlen_ll[i] = value; - else bitlen_d[i - HLIT] = value; - i++; - } - } - else if(code == 17) /*repeat "0" 3-10 times*/ - { - unsigned replength = 3; /*read in the bits that indicate repeat length*/ - if(*bp >= inbitlength) ERROR_BREAK(50); /*error, bit pointer jumps past memory*/ - - replength += readBitsFromStream(bp, in, 3); - - /*repeat this value in the next lengths*/ - for(n = 0; n < replength; n++) - { - if(i >= HLIT + HDIST) ERROR_BREAK(14); /*error: i is larger than the amount of codes*/ - - if(i < HLIT) bitlen_ll[i] = 0; - else bitlen_d[i - HLIT] = 0; - i++; - } - } - else if(code == 18) /*repeat "0" 11-138 times*/ - { - unsigned replength = 11; /*read in the bits that indicate repeat length*/ - if(*bp >= inbitlength) ERROR_BREAK(50); /*error, bit pointer jumps past memory*/ - - replength += readBitsFromStream(bp, in, 7); - - /*repeat this value in the next lengths*/ - for(n = 0; n < replength; n++) - { - if(i >= HLIT + HDIST) ERROR_BREAK(15); /*error: i is larger than the amount of codes*/ - - if(i < HLIT) bitlen_ll[i] = 0; - else bitlen_d[i - HLIT] = 0; - i++; - } - } - else /*if(code == (unsigned)(-1))*/ /*huffmanDecodeSymbol returns (unsigned)(-1) in case of error*/ - { - if(code == (unsigned)(-1)) - { - /*return error code 10 or 11 depending on the situation that happened in huffmanDecodeSymbol - (10=no endcode, 11=wrong jump outside of tree)*/ - error = (*bp) > inbitlength ? 10 : 11; - } - else error = 16; /*unexisting code, this can never happen*/ - break; - } - } - if(error) break; - - if(bitlen_ll[256] == 0) ERROR_BREAK(64); /*the length of the end code 256 must be larger than 0*/ - - /*now we've finally got HLIT and HDIST, so generate the code trees, and the function is done*/ - error = HuffmanTree_makeFromLengths(tree_ll, bitlen_ll, NUM_DEFLATE_CODE_SYMBOLS, 15); - if(error) break; - error = HuffmanTree_makeFromLengths(tree_d, bitlen_d, NUM_DISTANCE_SYMBOLS, 15); - - break; /*end of error-while*/ - } - - myfree(bitlen_cl); - myfree(bitlen_ll); - myfree(bitlen_d); - HuffmanTree_cleanup(&tree_cl); - - return error; -} - -/*inflate a block with dynamic of fixed Huffman tree*/ -static unsigned inflateHuffmanBlock(ucvector* out, const unsigned char* in, size_t* bp, - size_t* pos, size_t inlength, unsigned btype) -{ - unsigned error = 0; - HuffmanTree tree_ll; /*the huffman tree for literal and length codes*/ - HuffmanTree tree_d; /*the huffman tree for distance codes*/ - size_t inbitlength = inlength * 8; - - HuffmanTree_init(&tree_ll); - HuffmanTree_init(&tree_d); - - if(btype == 1) getTreeInflateFixed(&tree_ll, &tree_d); - else if(btype == 2) - { - error = getTreeInflateDynamic(&tree_ll, &tree_d, in, bp, inlength); - } - - while(!error) /*decode all symbols until end reached, breaks at end code*/ - { - /*code_ll is literal, length or end code*/ - unsigned code_ll = huffmanDecodeSymbol(in, bp, &tree_ll, inbitlength); - if(code_ll <= 255) /*literal symbol*/ - { - if((*pos) >= out->size) - { - /*reserve more room at once*/ - if(!ucvector_resize(out, ((*pos) + 1) * 2)) ERROR_BREAK(83 /*alloc fail*/); - } - out->data[(*pos)] = (unsigned char)(code_ll); - (*pos)++; - } - else if(code_ll >= FIRST_LENGTH_CODE_INDEX && code_ll <= LAST_LENGTH_CODE_INDEX) /*length code*/ - { - unsigned code_d, distance; - unsigned numextrabits_l, numextrabits_d; /*extra bits for length and distance*/ - size_t start, forward, backward, length; - - /*part 1: get length base*/ - length = LENGTHBASE[code_ll - FIRST_LENGTH_CODE_INDEX]; - - /*part 2: get extra bits and add the value of that to length*/ - numextrabits_l = LENGTHEXTRA[code_ll - FIRST_LENGTH_CODE_INDEX]; - if(*bp >= inbitlength) ERROR_BREAK(51); /*error, bit pointer will jump past memory*/ - length += readBitsFromStream(bp, in, numextrabits_l); - - /*part 3: get distance code*/ - code_d = huffmanDecodeSymbol(in, bp, &tree_d, inbitlength); - if(code_d > 29) - { - if(code_ll == (unsigned)(-1)) /*huffmanDecodeSymbol returns (unsigned)(-1) in case of error*/ - { - /*return error code 10 or 11 depending on the situation that happened in huffmanDecodeSymbol - (10=no endcode, 11=wrong jump outside of tree)*/ - error = (*bp) > inlength * 8 ? 10 : 11; - } - else error = 18; /*error: invalid distance code (30-31 are never used)*/ - break; - } - distance = DISTANCEBASE[code_d]; - - /*part 4: get extra bits from distance*/ - numextrabits_d = DISTANCEEXTRA[code_d]; - if(*bp >= inbitlength) ERROR_BREAK(51); /*error, bit pointer will jump past memory*/ - - distance += readBitsFromStream(bp, in, numextrabits_d); - - /*part 5: fill in all the out[n] values based on the length and dist*/ - start = (*pos); - if(distance > start) ERROR_BREAK(52); /*too long backward distance*/ - backward = start - distance; - if((*pos) + length >= out->size) - { - /*reserve more room at once*/ - if(!ucvector_resize(out, ((*pos) + length) * 2)) ERROR_BREAK(83 /*alloc fail*/); - } - - for(forward = 0; forward < length; forward++) - { - out->data[(*pos)] = out->data[backward]; - (*pos)++; - backward++; - if(backward >= start) backward = start - distance; - } - } - else if(code_ll == 256) - { - break; /*end code, break the loop*/ - } - else /*if(code == (unsigned)(-1))*/ /*huffmanDecodeSymbol returns (unsigned)(-1) in case of error*/ - { - /*return error code 10 or 11 depending on the situation that happened in huffmanDecodeSymbol - (10=no endcode, 11=wrong jump outside of tree)*/ - error = (*bp) > inlength * 8 ? 10 : 11; - break; - } - } - - HuffmanTree_cleanup(&tree_ll); - HuffmanTree_cleanup(&tree_d); - - return error; -} - -static unsigned inflateNoCompression(ucvector* out, const unsigned char* in, size_t* bp, size_t* pos, size_t inlength) -{ - /*go to first boundary of byte*/ - size_t p; - unsigned LEN, NLEN, n, error = 0; - while(((*bp) & 0x7) != 0) (*bp)++; - p = (*bp) / 8; /*byte position*/ - - /*read LEN (2 bytes) and NLEN (2 bytes)*/ - if(p >= inlength - 4) return 52; /*error, bit pointer will jump past memory*/ - LEN = in[p] + 256 * in[p + 1]; p += 2; - NLEN = in[p] + 256 * in[p + 1]; p += 2; - - /*check if 16-bit NLEN is really the one's complement of LEN*/ - if(LEN + NLEN != 65535) return 21; /*error: NLEN is not one's complement of LEN*/ - - if((*pos) + LEN >= out->size) - { - if(!ucvector_resize(out, (*pos) + LEN)) return 83; /*alloc fail*/ - } - - /*read the literal data: LEN bytes are now stored in the out buffer*/ - if(p + LEN > inlength) return 23; /*error: reading outside of in buffer*/ - for(n = 0; n < LEN; n++) out->data[(*pos)++] = in[p++]; - - (*bp) = p * 8; - - return error; -} - -static unsigned lodepng_inflatev(ucvector* out, - const unsigned char* in, size_t insize, - const LodePNGDecompressSettings* settings) -{ - /*bit pointer in the "in" data, current byte is bp >> 3, current bit is bp & 0x7 (from lsb to msb of the byte)*/ - size_t bp = 0; - unsigned BFINAL = 0; - size_t pos = 0; /*byte position in the out buffer*/ - - unsigned error = 0; - - (void)settings; - - while(!BFINAL) - { - unsigned BTYPE; - if(bp + 2 >= insize * 8) return 52; /*error, bit pointer will jump past memory*/ - BFINAL = readBitFromStream(&bp, in); - BTYPE = 1 * readBitFromStream(&bp, in); - BTYPE += 2 * readBitFromStream(&bp, in); - - if(BTYPE == 3) return 20; /*error: invalid BTYPE*/ - else if(BTYPE == 0) error = inflateNoCompression(out, in, &bp, &pos, insize); /*no compression*/ - else error = inflateHuffmanBlock(out, in, &bp, &pos, insize, BTYPE); /*compression, BTYPE 01 or 10*/ - - if(error) return error; - } - - /*Only now we know the true size of out, resize it to that*/ - if(!ucvector_resize(out, pos)) error = 83; /*alloc fail*/ - - return error; -} - -unsigned lodepng_inflate(unsigned char** out, size_t* outsize, - const unsigned char* in, size_t insize, - const LodePNGDecompressSettings* settings) -{ -#if LODEPNG_CUSTOM_ZLIB_DECODER == 2 - if(settings->custom_decoder) - { - return lodepng_custom_inflate(out, outsize, in, insize, settings); - } - else - { -#endif /*LODEPNG_CUSTOM_ZLIB_DECODER == 2*/ - unsigned error; - ucvector v; - ucvector_init_buffer(&v, *out, *outsize); - error = lodepng_inflatev(&v, in, insize, settings); - *out = v.data; - *outsize = v.size; - return error; -#if LODEPNG_CUSTOM_ZLIB_DECODER == 2 - } -#endif /*LODEPNG_CUSTOM_ZLIB_DECODER == 2*/ -} - -#endif /*LODEPNG_COMPILE_DECODER*/ - -#ifdef LODEPNG_COMPILE_ENCODER - -/* ////////////////////////////////////////////////////////////////////////// */ -/* / Deflator (Compressor) / */ -/* ////////////////////////////////////////////////////////////////////////// */ - -static const size_t MAX_SUPPORTED_DEFLATE_LENGTH = 258; - -/*bitlen is the size in bits of the code*/ -static void addHuffmanSymbol(size_t* bp, ucvector* compressed, unsigned code, unsigned bitlen) -{ - addBitsToStreamReversed(bp, compressed, code, bitlen); -} - -/*search the index in the array, that has the largest value smaller than or equal to the given value, -given array must be sorted (if no value is smaller, it returns the size of the given array)*/ -static size_t searchCodeIndex(const unsigned* array, size_t array_size, size_t value) -{ - /*linear search implementation*/ - /*for(size_t i = 1; i < array_size; i++) if(array[i] > value) return i - 1; - return array_size - 1;*/ - - /*binary search implementation (not that much faster) (precondition: array_size > 0)*/ - size_t left = 1; - size_t right = array_size - 1; - while(left <= right) - { - size_t mid = (left + right) / 2; - if(array[mid] <= value) left = mid + 1; /*the value to find is more to the right*/ - else if(array[mid - 1] > value) right = mid - 1; /*the value to find is more to the left*/ - else return mid - 1; - } - return array_size - 1; -} - -static void addLengthDistance(uivector* values, size_t length, size_t distance) -{ - /*values in encoded vector are those used by deflate: - 0-255: literal bytes - 256: end - 257-285: length/distance pair (length code, followed by extra length bits, distance code, extra distance bits) - 286-287: invalid*/ - - unsigned length_code = (unsigned)searchCodeIndex(LENGTHBASE, 29, length); - unsigned extra_length = (unsigned)(length - LENGTHBASE[length_code]); - unsigned dist_code = (unsigned)searchCodeIndex(DISTANCEBASE, 30, distance); - unsigned extra_distance = (unsigned)(distance - DISTANCEBASE[dist_code]); - - uivector_push_back(values, length_code + FIRST_LENGTH_CODE_INDEX); - uivector_push_back(values, extra_length); - uivector_push_back(values, dist_code); - uivector_push_back(values, extra_distance); -} - -static const unsigned HASH_NUM_VALUES = 65536; -static const unsigned HASH_NUM_CHARACTERS = 3; -static const unsigned HASH_SHIFT = 2; -/* -The HASH_NUM_CHARACTERS value is used to make encoding faster by using longer -sequences to generate a hash value from the stream bytes. Setting it to 3 -gives exactly the same compression as the brute force method, since deflate's -run length encoding starts with lengths of 3. Setting it to higher values, -like 6, can make the encoding faster (not always though!), but will cause the -encoding to miss any length between 3 and this value, so that the compression -may be worse (but this can vary too depending on the image, sometimes it is -even a bit better instead). -The HASH_NUM_VALUES is the amount of unique possible hash values that -combinations of bytes can give, the higher it is the more memory is needed, but -if it's too low the advantage of hashing is gone. -*/ - -typedef struct Hash -{ - int* head; /*hash value to head circular pos*/ - int* val; /*circular pos to hash value*/ - /*circular pos to prev circular pos*/ - unsigned short* chain; - unsigned short* zeros; -} Hash; - -static unsigned hash_init(Hash* hash, unsigned windowsize) -{ - unsigned i; - hash->head = (int*)mymalloc(sizeof(int) * HASH_NUM_VALUES); - hash->val = (int*)mymalloc(sizeof(int) * windowsize); - hash->chain = (unsigned short*)mymalloc(sizeof(unsigned short) * windowsize); - hash->zeros = (unsigned short*)mymalloc(sizeof(unsigned short) * windowsize); - - if(!hash->head || !hash->val || !hash->chain || !hash->zeros) return 83; /*alloc fail*/ - - /*initialize hash table*/ - for(i = 0; i < HASH_NUM_VALUES; i++) hash->head[i] = -1; - for(i = 0; i < windowsize; i++) hash->val[i] = -1; - for(i = 0; i < windowsize; i++) hash->chain[i] = i; /*same value as index indicates uninitialized*/ - - return 0; -} - -static void hash_cleanup(Hash* hash) -{ - myfree(hash->head); - myfree(hash->val); - myfree(hash->chain); - myfree(hash->zeros); -} - -static unsigned getHash(const unsigned char* data, size_t size, size_t pos) -{ - unsigned result = 0; - size_t amount, i; - if(pos >= size) return 0; - amount = HASH_NUM_CHARACTERS; - if(pos + amount >= size) amount = size - pos; - for(i = 0; i < amount; i++) result ^= (data[pos + i] << (i * HASH_SHIFT)); - return result % HASH_NUM_VALUES; -} - -static unsigned countZeros(const unsigned char* data, size_t size, size_t pos) -{ - const unsigned char* start = data + pos; - const unsigned char* end = start + MAX_SUPPORTED_DEFLATE_LENGTH; - if(end > data + size) end = data + size; - data = start; - while (data != end && *data == 0) data++; - return data - start; -} - -static void updateHashChain(Hash* hash, - size_t pos, int hashval, unsigned windowsize) -{ - unsigned wpos = pos % windowsize; - hash->val[wpos] = hashval; - if(hash->head[hashval] != -1) - { - hash->chain[wpos] = hash->head[hashval]; - } - hash->head[hashval] = wpos; -} - -/*Enable to use lazy instead of greedy matching. It looks one byte further -to see if that one gives a longer distance. This gives slightly better compression, at the cost -of a speed loss.*/ -#define LAZY_MATCHING - -/* -LZ77-encode the data. Return value is error code. The input are raw bytes, the output -is in the form of unsigned integers with codes representing for example literal bytes, or -length/distance pairs. -It uses a hash table technique to let it encode faster. When doing LZ77 encoding, a -sliding window (of windowsize) is used, and all past bytes in that window can be used as -the "dictionary". A brute force search through all possible distances would be slow, and -this hash technique is one out of several ways to speed this up. -*/ -static unsigned encodeLZ77(uivector* out, Hash* hash, - const unsigned char* in, size_t inpos, size_t insize, unsigned windowsize) -{ - unsigned short numzeros = 0; - int usezeros = windowsize >= 8192; /*for small window size, the 'max chain length' optimization does a better job*/ - unsigned pos, i, error = 0; - - if(!error) - { - unsigned offset; /*the offset represents the distance in LZ77 terminology*/ - unsigned length; -#ifdef LAZY_MATCHING - unsigned lazy = 0; - unsigned lazylength = 0, lazyoffset = 0; -#endif /*LAZY_MATCHING*/ - unsigned hashval; - unsigned current_offset, current_length; - const unsigned char *lastptr, *foreptr, *backptr; - unsigned short hashpos, prevpos; - - for(pos = inpos; pos < insize; pos++) - { - size_t wpos = pos % windowsize; /*position for in 'circular' hash buffers*/ - - hashval = getHash(in, insize, pos); - updateHashChain(hash, pos, hashval, windowsize); - - if(usezeros && hashval == 0) - { - numzeros = countZeros(in, insize, pos); - hash->zeros[wpos] = numzeros; - } - - /*the length and offset found for the current position*/ - length = 0; - offset = 0; - - prevpos = hash->head[hashval]; - hashpos = hash->chain[prevpos]; - - lastptr = &in[insize < pos + MAX_SUPPORTED_DEFLATE_LENGTH ? insize : pos + MAX_SUPPORTED_DEFLATE_LENGTH]; - - /*search for the longest string*/ - if(hash->val[wpos] == (int)hashval) - { - /*for large window lengths, assume the user wants no compression loss. Otherwise, max hash chain length speedup.*/ - unsigned maxchainlength = windowsize >= 8192 ? windowsize : windowsize / 8; - for(;;) - { - /*stop when went completely around the circular buffer*/ - if(prevpos < wpos && hashpos > prevpos && hashpos <= wpos) break; - if(prevpos > wpos && (hashpos <= wpos || hashpos > prevpos)) break; - if(maxchainlength-- == 0) break; - - current_offset = hashpos <= wpos ? wpos - hashpos : wpos - hashpos + windowsize; - if(current_offset > 0) - { - /*test the next characters*/ - foreptr = &in[pos]; - backptr = &in[pos - current_offset]; - - /*common case in PNGs is lots of zeros. Quickly skip over them as a speedup*/ - if(usezeros && hashval == 0 && hash->val[hashpos] == 0 /*hashval[hashpos] may be out of date*/) - { - unsigned short skip = hash->zeros[hashpos]; - if(skip > numzeros) skip = numzeros; - backptr += skip; - foreptr += skip; - } - - /* multiple checks at once per array bounds check */ - while(foreptr != lastptr && *backptr == *foreptr) /*maximum supported length by deflate is max length*/ - { - ++backptr; - ++foreptr; - } - current_length = (unsigned)(foreptr - &in[pos]); - - if(current_length > length) - { - length = current_length; /*the longest length*/ - offset = current_offset; /*the offset that is related to this longest length*/ - /*jump out once a length of max length is found (speed gain)*/ - if(current_length == MAX_SUPPORTED_DEFLATE_LENGTH) break; - } - } - - if(hashpos == hash->chain[hashpos]) break; - - prevpos = hashpos; - hashpos = hash->chain[hashpos]; - } - } - -#ifdef LAZY_MATCHING - if(!lazy && length >= 3 && length < MAX_SUPPORTED_DEFLATE_LENGTH) - { - lazy = 1; - lazylength = length; - lazyoffset = offset; - continue; - } - if(lazy) - { - lazy = 0; - if(pos == 0) ERROR_BREAK(81); - if(length > lazylength + 1) - { - /*push the previous character as literal*/ - if(!uivector_push_back(out, in[pos - 1])) ERROR_BREAK(83 /*alloc fail*/); - } - else - { - length = lazylength; - offset = lazyoffset; - hash->head[hashval] = -1; /*the same hashchain update will be done, this ensures no wrong alteration*/ - pos--; - } - } -#endif /*LAZY_MATCHING*/ - - if(length >= 3 && offset > windowsize) ERROR_BREAK(86 /*too big (or overflown negative) offset*/); - - - /**encode it as length/distance pair or literal value**/ - if(length < 3) /*only lengths of 3 or higher are supported as length/distance pair*/ - { - if(!uivector_push_back(out, in[pos])) ERROR_BREAK(83 /*alloc fail*/); - } - else - { - if(length == 3 && offset > 2048) - { - /*compensate for the fact that longer offsets have more extra bits, a - length of only 3 may be not worth it then*/ - if(!uivector_push_back(out, in[pos + 0])) ERROR_BREAK(83 /*alloc fail*/); - if(!uivector_push_back(out, in[pos + 1])) ERROR_BREAK(83 /*alloc fail*/); - if(!uivector_push_back(out, in[pos + 2])) ERROR_BREAK(83 /*alloc fail*/); - } - else - { - addLengthDistance(out, length, offset); - } - for(i = 1; i < length; i++) - { - pos++; - hashval = getHash(in, insize, pos); - updateHashChain(hash, pos, hashval, windowsize); - if(usezeros && hashval == 0) - { - hash->zeros[pos % windowsize] = countZeros(in, insize, pos); - } - } - } - - } /*end of the loop through each character of input*/ - } /*end of "if(!error)"*/ - - return error; -} - -/* /////////////////////////////////////////////////////////////////////////// */ - -static unsigned deflateNoCompression(ucvector* out, const unsigned char* data, size_t datasize) -{ - /*non compressed deflate block data: 1 bit BFINAL,2 bits BTYPE,(5 bits): it jumps to start of next byte, - 2 bytes LEN, 2 bytes NLEN, LEN bytes literal DATA*/ - - size_t i, j, numdeflateblocks = (datasize + 65534) / 65535; - unsigned datapos = 0; - for(i = 0; i < numdeflateblocks; i++) - { - unsigned BFINAL, BTYPE, LEN, NLEN; - unsigned char firstbyte; - - BFINAL = (i == numdeflateblocks - 1); - BTYPE = 0; - - firstbyte = (unsigned char)(BFINAL + ((BTYPE & 1) << 1) + ((BTYPE & 2) << 1)); - ucvector_push_back(out, firstbyte); - - LEN = 65535; - if(datasize - datapos < 65535) LEN = (unsigned)datasize - datapos; - NLEN = 65535 - LEN; - - ucvector_push_back(out, (unsigned char)(LEN % 256)); - ucvector_push_back(out, (unsigned char)(LEN / 256)); - ucvector_push_back(out, (unsigned char)(NLEN % 256)); - ucvector_push_back(out, (unsigned char)(NLEN / 256)); - - /*Decompressed data*/ - for(j = 0; j < 65535 && datapos < datasize; j++) - { - ucvector_push_back(out, data[datapos++]); - } - } - - return 0; -} - -/* -write the lz77-encoded data, which has lit, len and dist codes, to compressed stream using huffman trees. -tree_ll: the tree for lit and len codes. -tree_d: the tree for distance codes. -*/ -static void writeLZ77data(size_t* bp, ucvector* out, const uivector* lz77_encoded, - const HuffmanTree* tree_ll, const HuffmanTree* tree_d) -{ - size_t i = 0; - for(i = 0; i < lz77_encoded->size; i++) - { - unsigned val = lz77_encoded->data[i]; - addHuffmanSymbol(bp, out, HuffmanTree_getCode(tree_ll, val), HuffmanTree_getLength(tree_ll, val)); - if(val > 256) /*for a length code, 3 more things have to be added*/ - { - unsigned length_index = val - FIRST_LENGTH_CODE_INDEX; - unsigned n_length_extra_bits = LENGTHEXTRA[length_index]; - unsigned length_extra_bits = lz77_encoded->data[++i]; - - unsigned distance_code = lz77_encoded->data[++i]; - - unsigned distance_index = distance_code; - unsigned n_distance_extra_bits = DISTANCEEXTRA[distance_index]; - unsigned distance_extra_bits = lz77_encoded->data[++i]; - - addBitsToStream(bp, out, length_extra_bits, n_length_extra_bits); - addHuffmanSymbol(bp, out, HuffmanTree_getCode(tree_d, distance_code), - HuffmanTree_getLength(tree_d, distance_code)); - addBitsToStream(bp, out, distance_extra_bits, n_distance_extra_bits); - } - } -} - -/*Deflate for a block of type "dynamic", that is, with freely, optimally, created huffman trees*/ -static unsigned deflateDynamic(ucvector* out, size_t* bp, Hash* hash, - const unsigned char* data, size_t datapos, size_t dataend, - const LodePNGCompressSettings* settings, int final) -{ - unsigned error = 0; - - /* - A block is compressed as follows: The PNG data is lz77 encoded, resulting in - literal bytes and length/distance pairs. This is then huffman compressed with - two huffman trees. One huffman tree is used for the lit and len values ("ll"), - another huffman tree is used for the dist values ("d"). These two trees are - stored using their code lengths, and to compress even more these code lengths - are also run-length encoded and huffman compressed. This gives a huffman tree - of code lengths "cl". The code lenghts used to describe this third tree are - the code length code lengths ("clcl"). - */ - - /*The lz77 encoded data, represented with integers since there will also be length and distance codes in it*/ - uivector lz77_encoded; - HuffmanTree tree_ll; /*tree for lit,len values*/ - HuffmanTree tree_d; /*tree for distance codes*/ - HuffmanTree tree_cl; /*tree for encoding the code lengths representing tree_ll and tree_d*/ - uivector frequencies_ll; /*frequency of lit,len codes*/ - uivector frequencies_d; /*frequency of dist codes*/ - uivector frequencies_cl; /*frequency of code length codes*/ - uivector bitlen_lld; /*lit,len,dist code lenghts (int bits), literally (without repeat codes).*/ - uivector bitlen_lld_e; /*bitlen_lld encoded with repeat codes (this is a rudemtary run length compression)*/ - /*bitlen_cl is the code length code lengths ("clcl"). The bit lengths of codes to represent tree_cl - (these are written as is in the file, it would be crazy to compress these using yet another huffman - tree that needs to be represented by yet another set of code lengths)*/ - uivector bitlen_cl; - size_t datasize = dataend - datapos; - - /* - Due to the huffman compression of huffman tree representations ("two levels"), there are some anologies: - bitlen_lld is to tree_cl what data is to tree_ll and tree_d. - bitlen_lld_e is to bitlen_lld what lz77_encoded is to data. - bitlen_cl is to bitlen_lld_e what bitlen_lld is to lz77_encoded. - */ - - unsigned BFINAL = final; - size_t numcodes_ll, numcodes_d, i; - unsigned HLIT, HDIST, HCLEN; - - uivector_init(&lz77_encoded); - HuffmanTree_init(&tree_ll); - HuffmanTree_init(&tree_d); - HuffmanTree_init(&tree_cl); - uivector_init(&frequencies_ll); - uivector_init(&frequencies_d); - uivector_init(&frequencies_cl); - uivector_init(&bitlen_lld); - uivector_init(&bitlen_lld_e); - uivector_init(&bitlen_cl); - - /*This while loop is never loops due to a break at the end, it is here to - allow breaking out of it to the cleanup phase on error conditions.*/ - while(!error) - { - if(settings->use_lz77) - { - error = encodeLZ77(&lz77_encoded, hash, data, datapos, dataend, settings->windowsize); /*LZ77 encoded*/ - if(error) break; - } - else - { - if(!uivector_resize(&lz77_encoded, datasize)) ERROR_BREAK(83 /*alloc fail*/); - for(i = datapos; i < dataend; i++) lz77_encoded.data[i] = data[i]; /*no LZ77, but still will be Huffman compressed*/ - } - - if(!uivector_resizev(&frequencies_ll, 286, 0)) ERROR_BREAK(83 /*alloc fail*/); - if(!uivector_resizev(&frequencies_d, 30, 0)) ERROR_BREAK(83 /*alloc fail*/); - - /*Count the frequencies of lit, len and dist codes*/ - for(i = 0; i < lz77_encoded.size; i++) - { - unsigned symbol = lz77_encoded.data[i]; - frequencies_ll.data[symbol]++; - if(symbol > 256) - { - unsigned dist = lz77_encoded.data[i + 2]; - frequencies_d.data[dist]++; - i += 3; - } - } - frequencies_ll.data[256] = 1; /*there will be exactly 1 end code, at the end of the block*/ - - /*Make both huffman trees, one for the lit and len codes, one for the dist codes*/ - error = HuffmanTree_makeFromFrequencies(&tree_ll, frequencies_ll.data, frequencies_ll.size, 15); - if(error) break; - error = HuffmanTree_makeFromFrequencies(&tree_d, frequencies_d.data, frequencies_d.size, 15); - if(error) break; - - numcodes_ll = tree_ll.numcodes; if(numcodes_ll > 286) numcodes_ll = 286; - numcodes_d = tree_d.numcodes; if(numcodes_d > 30) numcodes_d = 30; - /*store the code lengths of both generated trees in bitlen_lld*/ - for(i = 0; i < numcodes_ll; i++) uivector_push_back(&bitlen_lld, HuffmanTree_getLength(&tree_ll, (unsigned)i)); - for(i = 0; i < numcodes_d; i++) uivector_push_back(&bitlen_lld, HuffmanTree_getLength(&tree_d, (unsigned)i)); - - /*run-length compress bitlen_ldd into bitlen_lld_e by using repeat codes 16 (copy length 3-6 times), - 17 (3-10 zeroes), 18 (11-138 zeroes)*/ - for(i = 0; i < (unsigned)bitlen_lld.size; i++) - { - unsigned j = 0; /*amount of repititions*/ - while(i + j + 1 < (unsigned)bitlen_lld.size && bitlen_lld.data[i + j + 1] == bitlen_lld.data[i]) j++; - - if(bitlen_lld.data[i] == 0 && j >= 2) /*repeat code for zeroes*/ - { - j++; /*include the first zero*/ - if(j <= 10) /*repeat code 17 supports max 10 zeroes*/ - { - uivector_push_back(&bitlen_lld_e, 17); - uivector_push_back(&bitlen_lld_e, j - 3); - } - else /*repeat code 18 supports max 138 zeroes*/ - { - if(j > 138) j = 138; - uivector_push_back(&bitlen_lld_e, 18); - uivector_push_back(&bitlen_lld_e, j - 11); - } - i += (j - 1); - } - else if(j >= 3) /*repeat code for value other than zero*/ - { - size_t k; - unsigned num = j / 6, rest = j % 6; - uivector_push_back(&bitlen_lld_e, bitlen_lld.data[i]); - for(k = 0; k < num; k++) - { - uivector_push_back(&bitlen_lld_e, 16); - uivector_push_back(&bitlen_lld_e, 6 - 3); - } - if(rest >= 3) - { - uivector_push_back(&bitlen_lld_e, 16); - uivector_push_back(&bitlen_lld_e, rest - 3); - } - else j -= rest; - i += j; - } - else /*too short to benefit from repeat code*/ - { - uivector_push_back(&bitlen_lld_e, bitlen_lld.data[i]); - } - } - - /*generate tree_cl, the huffmantree of huffmantrees*/ - - if(!uivector_resizev(&frequencies_cl, NUM_CODE_LENGTH_CODES, 0)) ERROR_BREAK(83 /*alloc fail*/); - for(i = 0; i < bitlen_lld_e.size; i++) - { - frequencies_cl.data[bitlen_lld_e.data[i]]++; - /*after a repeat code come the bits that specify the number of repetitions, - those don't need to be in the frequencies_cl calculation*/ - if(bitlen_lld_e.data[i] >= 16) i++; - } - - error = HuffmanTree_makeFromFrequencies(&tree_cl, frequencies_cl.data, frequencies_cl.size, 7); - if(error) break; - - if(!uivector_resize(&bitlen_cl, NUM_CODE_LENGTH_CODES)) ERROR_BREAK(83 /*alloc fail*/); - for(i = 0; i < NUM_CODE_LENGTH_CODES; i++) - { - /*lenghts of code length tree is in the order as specified by deflate*/ - bitlen_cl.data[i] = HuffmanTree_getLength(&tree_cl, CLCL_ORDER[i]); - } - while(bitlen_cl.data[bitlen_cl.size - 1] == 0 && bitlen_cl.size > 4) - { - /*remove zeros at the end, but minimum size must be 4*/ - if(!uivector_resize(&bitlen_cl, bitlen_cl.size - 1)) ERROR_BREAK(83 /*alloc fail*/); - } - if(error) break; - - /* - Write everything into the output - - After the BFINAL and BTYPE, the dynamic block consists out of the following: - - 5 bits HLIT, 5 bits HDIST, 4 bits HCLEN - - (HCLEN+4)*3 bits code lengths of code length alphabet - - HLIT + 257 code lenghts of lit/length alphabet (encoded using the code length - alphabet, + possible repetition codes 16, 17, 18) - - HDIST + 1 code lengths of distance alphabet (encoded using the code length - alphabet, + possible repetition codes 16, 17, 18) - - compressed data - - 256 (end code) - */ - - /*Write block type*/ - addBitToStream(bp, out, BFINAL); - addBitToStream(bp, out, 0); /*first bit of BTYPE "dynamic"*/ - addBitToStream(bp, out, 1); /*second bit of BTYPE "dynamic"*/ - - /*write the HLIT, HDIST and HCLEN values*/ - HLIT = (unsigned)(numcodes_ll - 257); - HDIST = (unsigned)(numcodes_d - 1); - HCLEN = (unsigned)bitlen_cl.size - 4; - addBitsToStream(bp, out, HLIT, 5); - addBitsToStream(bp, out, HDIST, 5); - addBitsToStream(bp, out, HCLEN, 4); - - /*write the code lenghts of the code length alphabet*/ - for(i = 0; i < HCLEN + 4; i++) addBitsToStream(bp, out, bitlen_cl.data[i], 3); - - /*write the lenghts of the lit/len AND the dist alphabet*/ - for(i = 0; i < bitlen_lld_e.size; i++) - { - addHuffmanSymbol(bp, out, HuffmanTree_getCode(&tree_cl, bitlen_lld_e.data[i]), - HuffmanTree_getLength(&tree_cl, bitlen_lld_e.data[i])); - /*extra bits of repeat codes*/ - if(bitlen_lld_e.data[i] == 16) addBitsToStream(bp, out, bitlen_lld_e.data[++i], 2); - else if(bitlen_lld_e.data[i] == 17) addBitsToStream(bp, out, bitlen_lld_e.data[++i], 3); - else if(bitlen_lld_e.data[i] == 18) addBitsToStream(bp, out, bitlen_lld_e.data[++i], 7); - } - - /*write the compressed data symbols*/ - writeLZ77data(bp, out, &lz77_encoded, &tree_ll, &tree_d); - /*error: the length of the end code 256 must be larger than 0*/ - if(HuffmanTree_getLength(&tree_ll, 256) == 0) ERROR_BREAK(64); - - /*write the end code*/ - addHuffmanSymbol(bp, out, HuffmanTree_getCode(&tree_ll, 256), HuffmanTree_getLength(&tree_ll, 256)); - - break; /*end of error-while*/ - } - - /*cleanup*/ - uivector_cleanup(&lz77_encoded); - HuffmanTree_cleanup(&tree_ll); - HuffmanTree_cleanup(&tree_d); - HuffmanTree_cleanup(&tree_cl); - uivector_cleanup(&frequencies_ll); - uivector_cleanup(&frequencies_d); - uivector_cleanup(&frequencies_cl); - uivector_cleanup(&bitlen_lld_e); - uivector_cleanup(&bitlen_lld); - uivector_cleanup(&bitlen_cl); - - return error; -} - -static unsigned deflateFixed(ucvector* out, size_t* bp, Hash* hash, - const unsigned char* data, - size_t datapos, size_t dataend, - const LodePNGCompressSettings* settings, int final) -{ - HuffmanTree tree_ll; /*tree for literal values and length codes*/ - HuffmanTree tree_d; /*tree for distance codes*/ - - unsigned BFINAL = final; - unsigned error = 0; - size_t i; - - HuffmanTree_init(&tree_ll); - HuffmanTree_init(&tree_d); - - generateFixedLitLenTree(&tree_ll); - generateFixedDistanceTree(&tree_d); - - addBitToStream(bp, out, BFINAL); - addBitToStream(bp, out, 1); /*first bit of BTYPE*/ - addBitToStream(bp, out, 0); /*second bit of BTYPE*/ - - if(settings->use_lz77) /*LZ77 encoded*/ - { - uivector lz77_encoded; - uivector_init(&lz77_encoded); - error = encodeLZ77(&lz77_encoded, hash, data, datapos, dataend, settings->windowsize); - if(!error) writeLZ77data(bp, out, &lz77_encoded, &tree_ll, &tree_d); - uivector_cleanup(&lz77_encoded); - } - else /*no LZ77, but still will be Huffman compressed*/ - { - for(i = datapos; i < dataend; i++) - { - addHuffmanSymbol(bp, out, HuffmanTree_getCode(&tree_ll, data[i]), HuffmanTree_getLength(&tree_ll, data[i])); - } - } - /*add END code*/ - if(!error) addHuffmanSymbol(bp, out, HuffmanTree_getCode(&tree_ll, 256), HuffmanTree_getLength(&tree_ll, 256)); - - /*cleanup*/ - HuffmanTree_cleanup(&tree_ll); - HuffmanTree_cleanup(&tree_d); - - return error; -} - -static unsigned lodepng_deflatev(ucvector* out, const unsigned char* in, size_t insize, - const LodePNGCompressSettings* settings) -{ -#if LODEPNG_CUSTOM_ZLIB_ENCODER == 2 - if(settings->custom_encoder) - { - unsigned char** out2 = &out->data; - size_t* outsize = &out->size; - - unsigned error = lodepng_custom_deflate(out2, outsize, in, insize, settings); - - if(!error) ucvector_init_buffer(out, *out2, *outsize); - return error; - } - else - { -#endif /*LODEPNG_CUSTOM_ZLIB_ENCODER == 2*/ - unsigned error = 0; - size_t i, blocksize, numdeflateblocks; - size_t bp = 0; /*the bit pointer*/ - Hash hash; - - if(settings->btype > 2) return 61; - - if(settings->btype == 0) return deflateNoCompression(out, in, insize); - - if(settings->btype == 1) blocksize = insize; - else /*if(settings->btype == 2)*/ - { - blocksize = insize / 8 + 8; - if(blocksize < 65535) blocksize = 65535; - } - - numdeflateblocks = (insize + blocksize - 1) / blocksize; - if(numdeflateblocks == 0) numdeflateblocks = 1; - - error = hash_init(&hash, settings->windowsize); - if(error) return error; - - for(i = 0; i < numdeflateblocks && !error; i++) - { - int final = i == numdeflateblocks - 1; - size_t start = i * blocksize; - size_t end = start + blocksize; - if(end > insize) end = insize; - - if(settings->btype == 1) error = deflateFixed(out, &bp, &hash, in, start, end, settings, final); - else if(settings->btype == 2) error = deflateDynamic(out, &bp, &hash, in, start, end, settings, final); - } - - hash_cleanup(&hash); - - return error; -#if LODEPNG_CUSTOM_ZLIB_ENCODER == 2 - } -#endif /*LODEPNG_CUSTOM_ZLIB_ENCODER == 2*/ -} - -unsigned lodepng_deflate(unsigned char** out, size_t* outsize, - const unsigned char* in, size_t insize, - const LodePNGCompressSettings* settings) -{ - unsigned error; - ucvector v; - ucvector_init_buffer(&v, *out, *outsize); - error = lodepng_deflatev(&v, in, insize, settings); - *out = v.data; - *outsize = v.size; - return error; -} - -#endif /*LODEPNG_COMPILE_DECODER*/ - -/* ////////////////////////////////////////////////////////////////////////// */ -/* / Adler32 */ -/* ////////////////////////////////////////////////////////////////////////// */ - -static unsigned update_adler32(unsigned adler, const unsigned char* data, unsigned len) -{ - unsigned s1 = adler & 0xffff; - unsigned s2 = (adler >> 16) & 0xffff; - - while(len > 0) - { - /*at least 5550 sums can be done before the sums overflow, saving a lot of module divisions*/ - unsigned amount = len > 5550 ? 5550 : len; - len -= amount; - while(amount > 0) - { - s1 = (s1 + *data++); - s2 = (s2 + s1); - amount--; - } - s1 %= 65521; - s2 %= 65521; - } - - return (s2 << 16) | s1; -} - -/*Return the adler32 of the bytes data[0..len-1]*/ -static unsigned adler32(const unsigned char* data, unsigned len) -{ - return update_adler32(1L, data, len); -} - -/* ////////////////////////////////////////////////////////////////////////// */ -/* / Zlib / */ -/* ////////////////////////////////////////////////////////////////////////// */ - -#ifdef LODEPNG_COMPILE_DECODER - -unsigned lodepng_zlib_decompress(unsigned char** out, size_t* outsize, const unsigned char* in, - size_t insize, const LodePNGDecompressSettings* settings) -{ -#if LODEPNG_CUSTOM_ZLIB_DECODER == 1 - if(settings->custom_decoder) - { - return lodepng_custom_zlib_decompress(out, outsize, in, insize, settings); - } - else - { -#endif /*LODEPNG_CUSTOM_ZLIB_DECODER == 1*/ - unsigned error = 0; - unsigned CM, CINFO, FDICT; - - if(insize < 2) return 53; /*error, size of zlib data too small*/ - /*read information from zlib header*/ - if((in[0] * 256 + in[1]) % 31 != 0) - { - /*error: 256 * in[0] + in[1] must be a multiple of 31, the FCHECK value is supposed to be made that way*/ - return 24; - } - - CM = in[0] & 15; - CINFO = (in[0] >> 4) & 15; - /*FCHECK = in[1] & 31;*/ /*FCHECK is already tested above*/ - FDICT = (in[1] >> 5) & 1; - /*FLEVEL = (in[1] >> 6) & 3;*/ /*FLEVEL is not used here*/ - - if(CM != 8 || CINFO > 7) - { - /*error: only compression method 8: inflate with sliding window of 32k is supported by the PNG spec*/ - return 25; - } - if(FDICT != 0) - { - /*error: the specification of PNG says about the zlib stream: - "The additional flags shall not specify a preset dictionary."*/ - return 26; - } - - error = lodepng_inflate(out, outsize, in + 2, insize - 2, settings); - if(error) return error; - - if(!settings->ignore_adler32) - { - unsigned ADLER32 = lodepng_read32bitInt(&in[insize - 4]); - unsigned checksum = adler32(*out, (unsigned)(*outsize)); - if(checksum != ADLER32) return 58; /*error, adler checksum not correct, data must be corrupted*/ - } - - return 0; /*no error*/ -#if LODEPNG_CUSTOM_ZLIB_DECODER == 1 - } -#endif /*LODEPNG_CUSTOM_ZLIB_DECODER == 1*/ -} - -#endif /*LODEPNG_COMPILE_DECODER*/ - -#ifdef LODEPNG_COMPILE_ENCODER - -unsigned lodepng_zlib_compress(unsigned char** out, size_t* outsize, const unsigned char* in, - size_t insize, const LodePNGCompressSettings* settings) -{ -#if LODEPNG_CUSTOM_ZLIB_ENCODER == 1 - if(settings->custom_encoder) - { - return lodepng_custom_zlib_compress(out, outsize, in, insize, settings); - } - else - { -#endif /*LODEPNG_CUSTOM_ZLIB_ENCODER == 1*/ - /*initially, *out must be NULL and outsize 0, if you just give some random *out - that's pointing to a non allocated buffer, this'll crash*/ - ucvector deflatedata, outv; - size_t i; - unsigned error; - - unsigned ADLER32; - /*zlib data: 1 byte CMF (CM+CINFO), 1 byte FLG, deflate data, 4 byte ADLER32 checksum of the Decompressed data*/ - unsigned CMF = 120; /*0b01111000: CM 8, CINFO 7. With CINFO 7, any window size up to 32768 can be used.*/ - unsigned FLEVEL = 0; - unsigned FDICT = 0; - unsigned CMFFLG = 256 * CMF + FDICT * 32 + FLEVEL * 64; - unsigned FCHECK = 31 - CMFFLG % 31; - CMFFLG += FCHECK; - - /*ucvector-controlled version of the output buffer, for dynamic array*/ - ucvector_init_buffer(&outv, *out, *outsize); - - ucvector_push_back(&outv, (unsigned char)(CMFFLG / 256)); - ucvector_push_back(&outv, (unsigned char)(CMFFLG % 256)); - - ucvector_init(&deflatedata); - error = lodepng_deflatev(&deflatedata, in, insize, settings); - - if(!error) - { - ADLER32 = adler32(in, (unsigned)insize); - for(i = 0; i < deflatedata.size; i++) ucvector_push_back(&outv, deflatedata.data[i]); - ucvector_cleanup(&deflatedata); - lodepng_add32bitInt(&outv, ADLER32); - } - - *out = outv.data; - *outsize = outv.size; - - return error; -#if LODEPNG_CUSTOM_ZLIB_ENCODER == 1 - } -#endif /*LODEPNG_CUSTOM_ZLIB_ENCODER == 1*/ -} - -#endif /*LODEPNG_COMPILE_ENCODER*/ - -#else /*no LODEPNG_COMPILE_ZLIB*/ - -#ifdef LODEPNG_COMPILE_DECODER -static unsigned lodepng_zlib_decompress(unsigned char** out, size_t* outsize, const unsigned char* in, - size_t insize, const LodePNGDecompressSettings* settings) -{ - return lodepng_custom_zlib_decompress(out, outsize, in, insize, settings); -} -#endif /*LODEPNG_COMPILE_DECODER*/ -#ifdef LODEPNG_COMPILE_ENCODER -static unsigned lodepng_zlib_compress(unsigned char** out, size_t* outsize, const unsigned char* in, - size_t insize, const LodePNGCompressSettings* settings) -{ - return lodepng_custom_zlib_compress(out, outsize, in, insize, settings); -} -#endif /*LODEPNG_COMPILE_ENCODER*/ - -#endif /*LODEPNG_COMPILE_ZLIB*/ - -/* ////////////////////////////////////////////////////////////////////////// */ - -#ifdef LODEPNG_COMPILE_ENCODER - -/*this is a good tradeoff between speed and compression ratio*/ -#define DEFAULT_WINDOWSIZE 2048 - -void lodepng_compress_settings_init(LodePNGCompressSettings* settings) -{ - /*compress with dynamic huffman tree (not in the mathematical sense, just not the predefined one)*/ - settings->btype = 2; - settings->use_lz77 = 1; - settings->windowsize = DEFAULT_WINDOWSIZE; -#if LODEPNG_CUSTOM_ZLIB_ENCODER == 0 - settings->custom_encoder = 0; -#else - settings->custom_encoder = 1; -#endif -} - -#if LODEPNG_CUSTOM_ZLIB_ENCODER == 0 -const LodePNGCompressSettings lodepng_default_compress_settings = {2, 1, DEFAULT_WINDOWSIZE, 0}; -#else -const LodePNGCompressSettings lodepng_default_compress_settings = {2, 1, DEFAULT_WINDOWSIZE, 1}; -#endif - - -#endif /*LODEPNG_COMPILE_ENCODER*/ - -#ifdef LODEPNG_COMPILE_DECODER - -void lodepng_decompress_settings_init(LodePNGDecompressSettings* settings) -{ - settings->ignore_adler32 = 0; -#if LODEPNG_CUSTOM_ZLIB_DECODER == 0 - settings->custom_decoder = 0; -#else - settings->custom_decoder = 1; -#endif -} - -#if LODEPNG_CUSTOM_ZLIB_DECODER == 0 -const LodePNGDecompressSettings lodepng_default_decompress_settings = {0, 0}; -#else -const LodePNGDecompressSettings lodepng_default_decompress_settings = {0, 1}; -#endif - -#endif /*LODEPNG_COMPILE_DECODER*/ - -/* ////////////////////////////////////////////////////////////////////////// */ -/* ////////////////////////////////////////////////////////////////////////// */ -/* // End of Zlib related code. Begin of PNG related code. // */ -/* ////////////////////////////////////////////////////////////////////////// */ -/* ////////////////////////////////////////////////////////////////////////// */ - -#ifdef LODEPNG_COMPILE_PNG - -/* ////////////////////////////////////////////////////////////////////////// */ -/* / CRC32 / */ -/* ////////////////////////////////////////////////////////////////////////// */ - -static unsigned Crc32_crc_table_computed = 0; -static unsigned Crc32_crc_table[256]; - -/*Make the table for a fast CRC.*/ -static void Crc32_make_crc_table(void) -{ - unsigned c, k, n; - for(n = 0; n < 256; n++) - { - c = n; - for(k = 0; k < 8; k++) - { - if(c & 1) c = 0xedb88320L ^ (c >> 1); - else c = c >> 1; - } - Crc32_crc_table[n] = c; - } - Crc32_crc_table_computed = 1; -} - -/*Update a running CRC with the bytes buf[0..len-1]--the CRC should be -initialized to all 1's, and the transmitted value is the 1's complement of the -final running CRC (see the crc() routine below).*/ -static unsigned Crc32_update_crc(const unsigned char* buf, unsigned crc, size_t len) -{ - unsigned c = crc; - size_t n; - - if(!Crc32_crc_table_computed) Crc32_make_crc_table(); - for(n = 0; n < len; n++) - { - c = Crc32_crc_table[(c ^ buf[n]) & 0xff] ^ (c >> 8); - } - return c; -} - -/*Return the CRC of the bytes buf[0..len-1].*/ -unsigned lodepng_crc32(const unsigned char* buf, size_t len) -{ - return Crc32_update_crc(buf, 0xffffffffL, len) ^ 0xffffffffL; -} - -/* ////////////////////////////////////////////////////////////////////////// */ -/* / Reading and writing single bits and bytes from/to stream for LodePNG / */ -/* ////////////////////////////////////////////////////////////////////////// */ - -static unsigned char readBitFromReversedStream(size_t* bitpointer, const unsigned char* bitstream) -{ - unsigned char result = (unsigned char)((bitstream[(*bitpointer) >> 3] >> (7 - ((*bitpointer) & 0x7))) & 1); - (*bitpointer)++; - return result; -} - -static unsigned readBitsFromReversedStream(size_t* bitpointer, const unsigned char* bitstream, size_t nbits) -{ - unsigned result = 0; - size_t i; - for(i = nbits - 1; i < nbits; i--) - { - result += (unsigned)readBitFromReversedStream(bitpointer, bitstream) << i; - } - return result; -} - -#ifdef LODEPNG_COMPILE_DECODER -static void setBitOfReversedStream0(size_t* bitpointer, unsigned char* bitstream, unsigned char bit) -{ - /*the current bit in bitstream must be 0 for this to work*/ - if(bit) - { - /*earlier bit of huffman code is in a lesser significant bit of an earlier byte*/ - bitstream[(*bitpointer) >> 3] |= (bit << (7 - ((*bitpointer) & 0x7))); - } - (*bitpointer)++; -} -#endif /*LODEPNG_COMPILE_DECODER*/ - -static void setBitOfReversedStream(size_t* bitpointer, unsigned char* bitstream, unsigned char bit) -{ - /*the current bit in bitstream may be 0 or 1 for this to work*/ - if(bit == 0) bitstream[(*bitpointer) >> 3] &= (unsigned char)(~(1 << (7 - ((*bitpointer) & 0x7)))); - else bitstream[(*bitpointer) >> 3] |= (1 << (7 - ((*bitpointer) & 0x7))); - (*bitpointer)++; -} - -/* ////////////////////////////////////////////////////////////////////////// */ -/* / PNG chunks / */ -/* ////////////////////////////////////////////////////////////////////////// */ - -unsigned lodepng_chunk_length(const unsigned char* chunk) -{ - return lodepng_read32bitInt(&chunk[0]); -} - -void lodepng_chunk_type(char type[5], const unsigned char* chunk) -{ - unsigned i; - for(i = 0; i < 4; i++) type[i] = chunk[4 + i]; - type[4] = 0; /*null termination char*/ -} - -unsigned char lodepng_chunk_type_equals(const unsigned char* chunk, const char* type) -{ - if(strlen(type) != 4) return 0; - return (chunk[4] == type[0] && chunk[5] == type[1] && chunk[6] == type[2] && chunk[7] == type[3]); -} - -unsigned char lodepng_chunk_ancillary(const unsigned char* chunk) -{ - return((chunk[4] & 32) != 0); -} - -unsigned char lodepng_chunk_private(const unsigned char* chunk) -{ - return((chunk[6] & 32) != 0); -} - -unsigned char lodepng_chunk_safetocopy(const unsigned char* chunk) -{ - return((chunk[7] & 32) != 0); -} - -unsigned char* lodepng_chunk_data(unsigned char* chunk) -{ - return &chunk[8]; -} - -const unsigned char* lodepng_chunk_data_const(const unsigned char* chunk) -{ - return &chunk[8]; -} - -unsigned lodepng_chunk_check_crc(const unsigned char* chunk) -{ - unsigned length = lodepng_chunk_length(chunk); - unsigned CRC = lodepng_read32bitInt(&chunk[length + 8]); - /*the CRC is taken of the data and the 4 chunk type letters, not the length*/ - unsigned checksum = lodepng_crc32(&chunk[4], length + 4); - if(CRC != checksum) return 1; - else return 0; -} - -void lodepng_chunk_generate_crc(unsigned char* chunk) -{ - unsigned length = lodepng_chunk_length(chunk); - unsigned CRC = lodepng_crc32(&chunk[4], length + 4); - lodepng_set32bitInt(chunk + 8 + length, CRC); -} - -unsigned char* lodepng_chunk_next(unsigned char* chunk) -{ - unsigned total_chunk_length = lodepng_chunk_length(chunk) + 12; - return &chunk[total_chunk_length]; -} - -const unsigned char* lodepng_chunk_next_const(const unsigned char* chunk) -{ - unsigned total_chunk_length = lodepng_chunk_length(chunk) + 12; - return &chunk[total_chunk_length]; -} - -unsigned lodepng_chunk_append(unsigned char** out, size_t* outlength, const unsigned char* chunk) -{ - unsigned i; - unsigned total_chunk_length = lodepng_chunk_length(chunk) + 12; - unsigned char *chunk_start, *new_buffer; - size_t new_length = (*outlength) + total_chunk_length; - if(new_length < total_chunk_length || new_length < (*outlength)) return 77; /*integer overflow happened*/ - - new_buffer = (unsigned char*)myrealloc(*out, new_length); - if(!new_buffer) return 83; /*alloc fail*/ - (*out) = new_buffer; - (*outlength) = new_length; - chunk_start = &(*out)[new_length - total_chunk_length]; - - for(i = 0; i < total_chunk_length; i++) chunk_start[i] = chunk[i]; - - return 0; -} - -unsigned lodepng_chunk_create(unsigned char** out, size_t* outlength, unsigned length, - const char* type, const unsigned char* data) -{ - unsigned i; - unsigned char *chunk, *new_buffer; - size_t new_length = (*outlength) + length + 12; - if(new_length < length + 12 || new_length < (*outlength)) return 77; /*integer overflow happened*/ - new_buffer = (unsigned char*)myrealloc(*out, new_length); - if(!new_buffer) return 83; /*alloc fail*/ - (*out) = new_buffer; - (*outlength) = new_length; - chunk = &(*out)[(*outlength) - length - 12]; - - /*1: length*/ - lodepng_set32bitInt(chunk, (unsigned)length); - - /*2: chunk name (4 letters)*/ - chunk[4] = type[0]; - chunk[5] = type[1]; - chunk[6] = type[2]; - chunk[7] = type[3]; - - /*3: the data*/ - for(i = 0; i < length; i++) chunk[8 + i] = data[i]; - - /*4: CRC (of the chunkname characters and the data)*/ - lodepng_chunk_generate_crc(chunk); - - return 0; -} - -/* ////////////////////////////////////////////////////////////////////////// */ -/* / Color types and such / */ -/* ////////////////////////////////////////////////////////////////////////// */ - -/*return type is a LodePNG error code*/ -static unsigned checkColorValidity(LodePNGColorType colortype, unsigned bd) /*bd = bitdepth*/ -{ - switch(colortype) - { - case 0: if(!(bd == 1 || bd == 2 || bd == 4 || bd == 8 || bd == 16)) return 37; break; /*grey*/ - case 2: if(!( bd == 8 || bd == 16)) return 37; break; /*RGB*/ - case 3: if(!(bd == 1 || bd == 2 || bd == 4 || bd == 8 )) return 37; break; /*palette*/ - case 4: if(!( bd == 8 || bd == 16)) return 37; break; /*grey + alpha*/ - case 6: if(!( bd == 8 || bd == 16)) return 37; break; /*RGBA*/ - default: return 31; - } - return 0; /*allowed color type / bits combination*/ -} - -static unsigned getNumColorChannels(LodePNGColorType colortype) -{ - switch(colortype) - { - case 0: return 1; /*grey*/ - case 2: return 3; /*RGB*/ - case 3: return 1; /*palette*/ - case 4: return 2; /*grey + alpha*/ - case 6: return 4; /*RGBA*/ - } - return 0; /*unexisting color type*/ -} - -static unsigned lodepng_get_bpp_lct(LodePNGColorType colortype, unsigned bitdepth) -{ - /*bits per pixel is amount of channels * bits per channel*/ - return getNumColorChannels(colortype) * bitdepth; -} - -/* ////////////////////////////////////////////////////////////////////////// */ - -void lodepng_color_mode_init(LodePNGColorMode* info) -{ - info->key_defined = 0; - info->key_r = info->key_g = info->key_b = 0; - info->colortype = LCT_RGBA; - info->bitdepth = 8; - info->palette = 0; - info->palettesize = 0; -} - -void lodepng_color_mode_cleanup(LodePNGColorMode* info) -{ - lodepng_palette_clear(info); -} - -unsigned lodepng_color_mode_copy(LodePNGColorMode* dest, const LodePNGColorMode* source) -{ - size_t i; - lodepng_color_mode_cleanup(dest); - *dest = *source; - if(source->palette) - { - dest->palette = (unsigned char*)mymalloc(source->palettesize * 4); - if(!dest->palette && source->palettesize) return 83; /*alloc fail*/ - for(i = 0; i < source->palettesize * 4; i++) dest->palette[i] = source->palette[i]; - } - return 0; -} - -static int lodepng_color_mode_equal(const LodePNGColorMode* a, const LodePNGColorMode* b) -{ - size_t i; - if(a->colortype != b->colortype) return 0; - if(a->bitdepth != b->bitdepth) return 0; - if(a->key_defined != b->key_defined) return 0; - if(a->key_defined) - { - if(a->key_r != b->key_r) return 0; - if(a->key_g != b->key_g) return 0; - if(a->key_b != b->key_b) return 0; - } - if(a->palettesize != b->palettesize) return 0; - for(i = 0; i < a->palettesize * 4; i++) - { - if(a->palette[i] != b->palette[i]) return 0; - } - return 1; -} - -void lodepng_palette_clear(LodePNGColorMode* info) -{ - if(info->palette) myfree(info->palette); - info->palettesize = 0; -} - -unsigned lodepng_palette_add(LodePNGColorMode* info, - unsigned char r, unsigned char g, unsigned char b, unsigned char a) -{ - unsigned char* data; - /*the same resize technique as C++ std::vectors is used, and here it's made so that for a palette with - the max of 256 colors, it'll have the exact alloc size*/ - if(!(info->palettesize & (info->palettesize - 1))) /*if palettesize is 0 or a power of two*/ - { - /*allocated data must be at least 4* palettesize (for 4 color bytes)*/ - size_t alloc_size = info->palettesize == 0 ? 4 : info->palettesize * 4 * 2; - data = (unsigned char*)myrealloc(info->palette, alloc_size); - if(!data) return 83; /*alloc fail*/ - else info->palette = data; - } - info->palette[4 * info->palettesize + 0] = r; - info->palette[4 * info->palettesize + 1] = g; - info->palette[4 * info->palettesize + 2] = b; - info->palette[4 * info->palettesize + 3] = a; - info->palettesize++; - return 0; -} - -unsigned lodepng_get_bpp(const LodePNGColorMode* info) -{ - /*calculate bits per pixel out of colortype and bitdepth*/ - return lodepng_get_bpp_lct(info->colortype, info->bitdepth); -} - -unsigned lodepng_get_channels(const LodePNGColorMode* info) -{ - return getNumColorChannels(info->colortype); -} - -unsigned lodepng_is_greyscale_type(const LodePNGColorMode* info) -{ - return info->colortype == LCT_GREY || info->colortype == LCT_GREY_ALPHA; -} - -unsigned lodepng_is_alpha_type(const LodePNGColorMode* info) -{ - return (info->colortype & 4) != 0; /*4 or 6*/ -} - -unsigned lodepng_is_palette_type(const LodePNGColorMode* info) -{ - return info->colortype == LCT_PALETTE; -} - -unsigned lodepng_has_palette_alpha(const LodePNGColorMode* info) -{ - size_t i; - for(i = 0; i < info->palettesize; i++) - { - if(info->palette[i * 4 + 3] < 255) return 1; - } - return 0; -} - -unsigned lodepng_can_have_alpha(const LodePNGColorMode* info) -{ - return info->key_defined - || lodepng_is_alpha_type(info) - || lodepng_has_palette_alpha(info); -} - -size_t lodepng_get_raw_size(unsigned w, unsigned h, const LodePNGColorMode* color) -{ - return (w * h * lodepng_get_bpp(color) + 7) / 8; -} - -size_t lodepng_get_raw_size_lct(unsigned w, unsigned h, LodePNGColorType colortype, unsigned bitdepth) -{ - return (w * h * lodepng_get_bpp_lct(colortype, bitdepth) + 7) / 8; -} - -#ifdef LODEPNG_COMPILE_ANCILLARY_CHUNKS - -static void LodePNGUnknownChunks_init(LodePNGInfo* info) -{ - unsigned i; - for(i = 0; i < 3; i++) info->unknown_chunks_data[i] = 0; - for(i = 0; i < 3; i++) info->unknown_chunks_size[i] = 0; -} - -static void LodePNGUnknownChunks_cleanup(LodePNGInfo* info) -{ - unsigned i; - for(i = 0; i < 3; i++) myfree(info->unknown_chunks_data[i]); -} - -static unsigned LodePNGUnknownChunks_copy(LodePNGInfo* dest, const LodePNGInfo* src) -{ - unsigned i; - - LodePNGUnknownChunks_cleanup(dest); - - for(i = 0; i < 3; i++) - { - size_t j; - dest->unknown_chunks_size[i] = src->unknown_chunks_size[i]; - dest->unknown_chunks_data[i] = (unsigned char*)mymalloc(src->unknown_chunks_size[i]); - if(!dest->unknown_chunks_data[i] && dest->unknown_chunks_size[i]) return 83; /*alloc fail*/ - for(j = 0; j < src->unknown_chunks_size[i]; j++) - { - dest->unknown_chunks_data[i][j] = src->unknown_chunks_data[i][j]; - } - } - - return 0; -} - -/******************************************************************************/ - -static void LodePNGText_init(LodePNGInfo* info) -{ - info->text_num = 0; - info->text_keys = NULL; - info->text_strings = NULL; -} - -static void LodePNGText_cleanup(LodePNGInfo* info) -{ - size_t i; - for(i = 0; i < info->text_num; i++) - { - string_cleanup(&info->text_keys[i]); - string_cleanup(&info->text_strings[i]); - } - myfree(info->text_keys); - myfree(info->text_strings); -} - -static unsigned LodePNGText_copy(LodePNGInfo* dest, const LodePNGInfo* source) -{ - size_t i = 0; - dest->text_keys = 0; - dest->text_strings = 0; - dest->text_num = 0; - for(i = 0; i < source->text_num; i++) - { - CERROR_TRY_RETURN(lodepng_add_text(dest, source->text_keys[i], source->text_strings[i])); - } - return 0; -} - -void lodepng_clear_text(LodePNGInfo* info) -{ - LodePNGText_cleanup(info); -} - -unsigned lodepng_add_text(LodePNGInfo* info, const char* key, const char* str) -{ - char** new_keys = (char**)(myrealloc(info->text_keys, sizeof(char*) * (info->text_num + 1))); - char** new_strings = (char**)(myrealloc(info->text_strings, sizeof(char*) * (info->text_num + 1))); - if(!new_keys || !new_strings) - { - myfree(new_keys); - myfree(new_strings); - return 83; /*alloc fail*/ - } - - info->text_num++; - info->text_keys = new_keys; - info->text_strings = new_strings; - - string_init(&info->text_keys[info->text_num - 1]); - string_set(&info->text_keys[info->text_num - 1], key); - - string_init(&info->text_strings[info->text_num - 1]); - string_set(&info->text_strings[info->text_num - 1], str); - - return 0; -} - -/******************************************************************************/ - -static void LodePNGIText_init(LodePNGInfo* info) -{ - info->itext_num = 0; - info->itext_keys = NULL; - info->itext_langtags = NULL; - info->itext_transkeys = NULL; - info->itext_strings = NULL; -} - -static void LodePNGIText_cleanup(LodePNGInfo* info) -{ - size_t i; - for(i = 0; i < info->itext_num; i++) - { - string_cleanup(&info->itext_keys[i]); - string_cleanup(&info->itext_langtags[i]); - string_cleanup(&info->itext_transkeys[i]); - string_cleanup(&info->itext_strings[i]); - } - myfree(info->itext_keys); - myfree(info->itext_langtags); - myfree(info->itext_transkeys); - myfree(info->itext_strings); -} - -static unsigned LodePNGIText_copy(LodePNGInfo* dest, const LodePNGInfo* source) -{ - size_t i = 0; - dest->itext_keys = 0; - dest->itext_langtags = 0; - dest->itext_transkeys = 0; - dest->itext_strings = 0; - dest->itext_num = 0; - for(i = 0; i < source->itext_num; i++) - { - CERROR_TRY_RETURN(lodepng_add_itext(dest, source->itext_keys[i], source->itext_langtags[i], - source->itext_transkeys[i], source->itext_strings[i])); - } - return 0; -} - -void lodepng_clear_itext(LodePNGInfo* info) -{ - LodePNGIText_cleanup(info); -} - -unsigned lodepng_add_itext(LodePNGInfo* info, const char* key, const char* langtag, - const char* transkey, const char* str) -{ - char** new_keys = (char**)(myrealloc(info->itext_keys, sizeof(char*) * (info->itext_num + 1))); - char** new_langtags = (char**)(myrealloc(info->itext_langtags, sizeof(char*) * (info->itext_num + 1))); - char** new_transkeys = (char**)(myrealloc(info->itext_transkeys, sizeof(char*) * (info->itext_num + 1))); - char** new_strings = (char**)(myrealloc(info->itext_strings, sizeof(char*) * (info->itext_num + 1))); - if(!new_keys || !new_langtags || !new_transkeys || !new_strings) - { - myfree(new_keys); - myfree(new_langtags); - myfree(new_transkeys); - myfree(new_strings); - return 83; /*alloc fail*/ - } - - info->itext_num++; - info->itext_keys = new_keys; - info->itext_langtags = new_langtags; - info->itext_transkeys = new_transkeys; - info->itext_strings = new_strings; - - string_init(&info->itext_keys[info->itext_num - 1]); - string_set(&info->itext_keys[info->itext_num - 1], key); - - string_init(&info->itext_langtags[info->itext_num - 1]); - string_set(&info->itext_langtags[info->itext_num - 1], langtag); - - string_init(&info->itext_transkeys[info->itext_num - 1]); - string_set(&info->itext_transkeys[info->itext_num - 1], transkey); - - string_init(&info->itext_strings[info->itext_num - 1]); - string_set(&info->itext_strings[info->itext_num - 1], str); - - return 0; -} -#endif /*LODEPNG_COMPILE_ANCILLARY_CHUNKS*/ - -void lodepng_info_init(LodePNGInfo* info) -{ - lodepng_color_mode_init(&info->color); - info->interlace_method = 0; - info->compression_method = 0; - info->filter_method = 0; -#ifdef LODEPNG_COMPILE_ANCILLARY_CHUNKS - info->background_defined = 0; - info->background_r = info->background_g = info->background_b = 0; - - LodePNGText_init(info); - LodePNGIText_init(info); - - info->time_defined = 0; - info->phys_defined = 0; - - LodePNGUnknownChunks_init(info); -#endif /*LODEPNG_COMPILE_ANCILLARY_CHUNKS*/ -} - -void lodepng_info_cleanup(LodePNGInfo* info) -{ - lodepng_color_mode_cleanup(&info->color); -#ifdef LODEPNG_COMPILE_ANCILLARY_CHUNKS - LodePNGText_cleanup(info); - LodePNGIText_cleanup(info); - - LodePNGUnknownChunks_cleanup(info); -#endif /*LODEPNG_COMPILE_ANCILLARY_CHUNKS*/ -} - -unsigned lodepng_info_copy(LodePNGInfo* dest, const LodePNGInfo* source) -{ - lodepng_info_cleanup(dest); - *dest = *source; - lodepng_color_mode_init(&dest->color); - CERROR_TRY_RETURN(lodepng_color_mode_copy(&dest->color, &source->color)); - -#ifdef LODEPNG_COMPILE_ANCILLARY_CHUNKS - CERROR_TRY_RETURN(LodePNGText_copy(dest, source)); - CERROR_TRY_RETURN(LodePNGIText_copy(dest, source)); - - LodePNGUnknownChunks_init(dest); - CERROR_TRY_RETURN(LodePNGUnknownChunks_copy(dest, source)); -#endif /*LODEPNG_COMPILE_ANCILLARY_CHUNKS*/ - return 0; -} - -void lodepng_info_swap(LodePNGInfo* a, LodePNGInfo* b) -{ - LodePNGInfo temp = *a; - *a = *b; - *b = temp; -} - -/* ////////////////////////////////////////////////////////////////////////// */ - -/*index: bitgroup index, bits: bitgroup size(1, 2 or 4, in: bitgroup value, out: octet array to add bits to*/ -static void addColorBits(unsigned char* out, size_t index, unsigned bits, unsigned in) -{ - /*p = the partial index in the byte, e.g. with 4 palettebits it is 0 for first half or 1 for second half*/ - unsigned p = index % (8 / bits); - in &= (1 << bits) - 1; /*filter out any other bits of the input value*/ - in = in << (bits * (8 / bits - p - 1)); - if(p == 0) out[index * bits / 8] = in; - else out[index * bits / 8] |= in; -} - -typedef struct ColorTree ColorTree; - -/* -One node of a color tree -This is the data structure used to count the number of unique colors and to get a palette -index for a color. It's a bit like an octree for RGB bits, except that a node has 256 -children and there is one level of the tree per color channel. This may use more memory -than an octree, but this is only used to count up to 256 so it's good enough. -*/ -struct ColorTree -{ - ColorTree* next; /*null, or array of 256 pointers to ColorTree of next level*/ - int index; /*the payload. Only has a meaningful value if this is in the 4th level*/ -}; - -static void color_tree_make_next(ColorTree* tree); - -/*next: whether to create the next array or not*/ -static void color_tree_init(ColorTree* tree, int next) -{ - if(next) color_tree_make_next(tree); - else tree->next = 0; - tree->index = -1; -} - -static void color_tree_make_next(ColorTree* tree) -{ - int i; - tree->next = (ColorTree*)mymalloc(256 * sizeof(ColorTree)); - for(i = 0; i < 256; i++) color_tree_init(&tree->next[i], 0); -} - -static void color_tree_cleanup(ColorTree* tree) -{ - if(tree->next) - { - int i; - for(i = 0; i < 256; i++) color_tree_cleanup(&tree->next[i]); - myfree(tree->next); - } -} - -/*returns -1 if color not present, its index otherwise*/ -static int color_tree_get(ColorTree* tree, unsigned char r, unsigned char g, unsigned char b, unsigned char a) -{ - tree = &tree->next[r]; - if(tree->next == 0) return -1; - tree = &tree->next[g]; - if(tree->next == 0) return -1; - tree = &tree->next[b]; - if(tree->next == 0) return -1; - tree = &tree->next[a]; - - return tree->index; -} - -#ifdef LODEPNG_COMPILE_ENCODER -static int color_tree_has(ColorTree* tree, unsigned char r, unsigned char g, unsigned char b, unsigned char a) -{ - return color_tree_get(tree, r, g, b, a) >= 0; -} -#endif /*LODEPNG_COMPILE_ENCODER*/ - -/*color is not allowed to already exist. Index should be >= 0 (it's signed to be compatible with using -1 for "doesn't exist")*/ -static void color_tree_add(ColorTree* tree, unsigned char r, unsigned char g, unsigned char b, unsigned char a, int index) -{ - tree = &tree->next[r]; - if(tree->next == 0) color_tree_make_next(tree); - tree = &tree->next[g]; - if(tree->next == 0) color_tree_make_next(tree); - tree = &tree->next[b]; - if(tree->next == 0) color_tree_make_next(tree); - tree = &tree->next[a]; - - tree->index = index; -} - -/*put a pixel, given its RGBA color, into image of any color type*/ -static unsigned rgba8ToPixel(unsigned char* out, size_t i, - const LodePNGColorMode* mode, ColorTree* tree /*for palette*/, - unsigned char r, unsigned char g, unsigned char b, unsigned char a) -{ - if(mode->colortype == LCT_GREY) - { - unsigned char grey = r; /*((unsigned short)r + g + b) / 3*/; - if(mode->bitdepth == 8) out[i] = grey; - else if(mode->bitdepth == 16) out[i * 2 + 0] = out[i * 2 + 1] = grey; - else - { - /*take the most significant bits of grey*/ - grey = (grey >> (8 - mode->bitdepth)) & ((1 << mode->bitdepth) - 1); - addColorBits(out, i, mode->bitdepth, grey); - } - } - else if(mode->colortype == LCT_RGB) - { - if(mode->bitdepth == 8) - { - out[i * 3 + 0] = r; - out[i * 3 + 1] = g; - out[i * 3 + 2] = b; - } - else - { - out[i * 6 + 0] = out[i * 6 + 1] = r; - out[i * 6 + 2] = out[i * 6 + 3] = g; - out[i * 6 + 4] = out[i * 6 + 5] = b; - } - } - else if(mode->colortype == LCT_PALETTE) - { - int index = color_tree_get(tree, r, g, b, a); - if(index < 0) return 82; /*color not in palette*/ - if(mode->bitdepth == 8) out[i] = index; - else addColorBits(out, i, mode->bitdepth, index); - } - else if(mode->colortype == LCT_GREY_ALPHA) - { - unsigned char grey = r; /*((unsigned short)r + g + b) / 3*/; - if(mode->bitdepth == 8) - { - out[i * 2 + 0] = grey; - out[i * 2 + 1] = a; - } - else if(mode->bitdepth == 16) - { - out[i * 4 + 0] = out[i * 4 + 1] = grey; - out[i * 4 + 2] = out[i * 4 + 3] = a; - } - } - else if(mode->colortype == LCT_RGBA) - { - if(mode->bitdepth == 8) - { - out[i * 4 + 0] = r; - out[i * 4 + 1] = g; - out[i * 4 + 2] = b; - out[i * 4 + 3] = a; - } - else - { - out[i * 8 + 0] = out[i * 8 + 1] = r; - out[i * 8 + 2] = out[i * 8 + 3] = g; - out[i * 8 + 4] = out[i * 8 + 5] = b; - out[i * 8 + 6] = out[i * 8 + 7] = a; - } - } - - return 0; /*no error*/ -} - -/*put a pixel, given its RGBA16 color, into image of any color 16-bitdepth type*/ -static unsigned rgba16ToPixel(unsigned char* out, size_t i, - const LodePNGColorMode* mode, - unsigned short r, unsigned short g, unsigned short b, unsigned short a) -{ - if(mode->bitdepth != 16) return 85; /*must be 16 for this function*/ - if(mode->colortype == LCT_GREY) - { - unsigned short grey = r; /*((unsigned)r + g + b) / 3*/; - out[i * 2 + 0] = (grey >> 8) & 255; - out[i * 2 + 1] = grey & 255; - } - else if(mode->colortype == LCT_RGB) - { - out[i * 6 + 0] = (r >> 8) & 255; - out[i * 6 + 1] = r & 255; - out[i * 6 + 2] = (g >> 8) & 255; - out[i * 6 + 3] = g & 255; - out[i * 6 + 4] = (b >> 8) & 255; - out[i * 6 + 5] = b & 255; - } - else if(mode->colortype == LCT_GREY_ALPHA) - { - unsigned short grey = r; /*((unsigned)r + g + b) / 3*/; - out[i * 4 + 0] = (grey >> 8) & 255; - out[i * 4 + 1] = grey & 255; - out[i * 4 + 2] = (a >> 8) & 255; - out[i * 4 + 3] = a & 255; - } - else if(mode->colortype == LCT_RGBA) - { - out[i * 8 + 0] = (r >> 8) & 255; - out[i * 8 + 1] = r & 255; - out[i * 8 + 2] = (g >> 8) & 255; - out[i * 8 + 3] = g & 255; - out[i * 8 + 4] = (b >> 8) & 255; - out[i * 8 + 5] = b & 255; - out[i * 8 + 6] = (a >> 8) & 255; - out[i * 8 + 7] = a & 255; - } - - return 0; /*no error*/ -} - -/*Get RGBA8 color of pixel with index i (y * width + x) from the raw image with given color type.*/ -static unsigned getPixelColorRGBA8(unsigned char* r, unsigned char* g, unsigned char* b, unsigned char* a, - const unsigned char* in, size_t i, const LodePNGColorMode* mode) -{ - if(mode->colortype == LCT_GREY) - { - if(mode->bitdepth == 8) - { - *r = *g = *b = in[i]; - if(mode->key_defined && *r == mode->key_r) *a = 0; - else *a = 255; - } - else if(mode->bitdepth == 16) - { - *r = *g = *b = in[i * 2 + 0]; - if(mode->key_defined && 256U * in[i * 2 + 0] + in[i * 2 + 1] == mode->key_r) *a = 0; - else *a = 255; - } - else - { - unsigned highest = ((1U << mode->bitdepth) - 1U); /*highest possible value for this bit depth*/ - size_t j = i * mode->bitdepth; - unsigned value = readBitsFromReversedStream(&j, in, mode->bitdepth); - *r = *g = *b = (value * 255) / highest; - if(mode->key_defined && value == mode->key_r) *a = 0; - else *a = 255; - } - } - else if(mode->colortype == LCT_RGB) - { - if(mode->bitdepth == 8) - { - *r = in[i * 3 + 0]; *g = in[i * 3 + 1]; *b = in[i * 3 + 2]; - if(mode->key_defined && *r == mode->key_r && *g == mode->key_g && *b == mode->key_b) *a = 0; - else *a = 255; - } - else - { - *r = in[i * 6 + 0]; - *g = in[i * 6 + 2]; - *b = in[i * 6 + 4]; - if(mode->key_defined && 256U * in[i * 6 + 0] + in[i * 6 + 1] == mode->key_r - && 256U * in[i * 6 + 2] + in[i * 6 + 3] == mode->key_g - && 256U * in[i * 6 + 4] + in[i * 6 + 5] == mode->key_b) *a = 0; - else *a = 255; - } - } - else if(mode->colortype == LCT_PALETTE) - { - unsigned index; - if(mode->bitdepth == 8) index = in[i]; - else - { - size_t j = i * mode->bitdepth; - index = readBitsFromReversedStream(&j, in, mode->bitdepth); - } - if(index >= mode->palettesize) return 47; /*index out of palette*/ - *r = mode->palette[index * 4 + 0]; - *g = mode->palette[index * 4 + 1]; - *b = mode->palette[index * 4 + 2]; - *a = mode->palette[index * 4 + 3]; - } - else if(mode->colortype == LCT_GREY_ALPHA) - { - if(mode->bitdepth == 8) - { - *r = *g = *b = in[i * 2 + 0]; - *a = in[i * 2 + 1]; - } - else - { - *r = *g = *b = in[i * 4 + 0]; - *a = in[i * 4 + 2]; - } - } - else if(mode->colortype == LCT_RGBA) - { - if(mode->bitdepth == 8) - { - *r = in[i * 4 + 0]; *g = in[i * 4 + 1]; *b = in[i * 4 + 2]; *a = in[i * 4 + 3]; - } - else - { - *r = in[i * 8 + 0]; *g = in[i * 8 + 2]; *b = in[i * 8 + 4]; *a = in[i * 8 + 6]; - } - } - - return 0; /*no error*/ -} - -/*Get RGBA16 color of pixel with index i (y * width + x) from the raw image with -given color type, but the given color type must be 16-bit itself.*/ -static unsigned getPixelColorRGBA16(unsigned short* r, unsigned short* g, unsigned short* b, unsigned short* a, - const unsigned char* in, size_t i, const LodePNGColorMode* mode) -{ - if(mode->bitdepth != 16) return 85; /*error: this function only supports 16-bit input*/ - - if(mode->colortype == LCT_GREY) - { - *r = *g = *b = 256 * in[i * 2 + 0] + in[i * 2 + 1]; - if(mode->key_defined && 256U * in[i * 2 + 0] + in[i * 2 + 1] == mode->key_r) *a = 0; - else *a = 65535; - } - else if(mode->colortype == LCT_RGB) - { - *r = 256 * in[i * 6 + 0] + in[i * 6 + 1]; - *g = 256 * in[i * 6 + 2] + in[i * 6 + 3]; - *b = 256 * in[i * 6 + 4] + in[i * 6 + 5]; - if(mode->key_defined && 256U * in[i * 6 + 0] + in[i * 6 + 1] == mode->key_r - && 256U * in[i * 6 + 2] + in[i * 6 + 3] == mode->key_g - && 256U * in[i * 6 + 4] + in[i * 6 + 5] == mode->key_b) *a = 0; - else *a = 65535; - } - else if(mode->colortype == LCT_GREY_ALPHA) - { - *r = *g = *b = 256 * in[i * 4 + 0] + in[i * 4 + 1]; - *a = 256 * in[i * 4 + 2] + in[i * 4 + 3]; - } - else if(mode->colortype == LCT_RGBA) - { - *r = 256 * in[i * 8 + 0] + in[i * 8 + 1]; - *g = 256 * in[i * 8 + 2] + in[i * 8 + 3]; - *b = 256 * in[i * 8 + 4] + in[i * 8 + 5]; - *a = 256 * in[i * 8 + 6] + in[i * 8 + 7]; - } - else return 85; /*error: this function only supports 16-bit input*/ - - return 0; /*no error*/ -} - -/* -converts from any color type to 24-bit or 32-bit (later maybe more supported). return value = LodePNG error code -the out buffer must have (w * h * bpp + 7) / 8 bytes, where bpp is the bits per pixel of the output color type -(lodepng_get_bpp) for < 8 bpp images, there may _not_ be padding bits at the end of scanlines. -*/ -unsigned lodepng_convert(unsigned char* out, const unsigned char* in, - LodePNGColorMode* mode_out, LodePNGColorMode* mode_in, - unsigned w, unsigned h) -{ - unsigned error = 0; - size_t i; - ColorTree tree; - - if(lodepng_color_mode_equal(mode_out, mode_in)) - { - size_t numbytes = lodepng_get_raw_size(w, h, mode_in); - for(i = 0; i < numbytes; i++) out[i] = in[i]; - return error; - } - - if(mode_out->colortype == LCT_PALETTE) - { - size_t palsize = 1 << mode_out->bitdepth; - if(mode_out->palettesize < palsize) palsize = mode_out->palettesize; - color_tree_init(&tree, 1); - for(i = 0; i < palsize; i++) - { - unsigned char* p = &mode_out->palette[i * 4]; - color_tree_add(&tree, p[0], p[1], p[2], p[3], i); - } - } - - if(mode_in->bitdepth == 16 && mode_out->bitdepth == 16) - { - size_t numpixels = w * h; - for(i = 0; i < numpixels; i++) - { - unsigned short r = 0, g = 0, b = 0, a = 0; - error = getPixelColorRGBA16(&r, &g, &b, &a, in, i, mode_in); - if(error) return error; - error = rgba16ToPixel(out, i, mode_out, r, g, b, a); - if(error) return error; - } - } - else - { - size_t numpixels = w * h; - for(i = 0; i < numpixels; i++) - { - unsigned char r = 0, g = 0, b = 0, a = 0; - error = getPixelColorRGBA8(&r, &g, &b, &a, in, i, mode_in); - if(error) return error; - error = rgba8ToPixel(out, i, mode_out, &tree, r, g, b, a); - if(error) return error; - } - } - - if(mode_out->colortype == LCT_PALETTE) - { - color_tree_cleanup(&tree); - } - - return error; -} - -#ifdef LODEPNG_COMPILE_ENCODER - -typedef struct ColorProfile -{ - unsigned char sixteenbit; /*needs more than 8 bits per channel*/ - unsigned char sixteenbit_done; - - - unsigned char colored; /*not greyscale*/ - unsigned char colored_done; - - unsigned char key; /*a color key is required, or more*/ - unsigned short key_r; /*these values are always in 16-bit bitdepth in the profile*/ - unsigned short key_g; - unsigned short key_b; - unsigned char alpha; /*alpha channel, or alpha palette, required*/ - unsigned char alpha_done; - - unsigned numcolors; - ColorTree tree; /*for listing the counted colors, up to 256*/ - unsigned char* palette; /*size 1024. Remember up to the first 256 RGBA colors*/ - unsigned maxnumcolors; /*if more than that amount counted*/ - unsigned char numcolors_done; - - unsigned greybits; /*amount of bits required for greyscale (1, 2, 4, 8). Does not take 16 bit into account.*/ - unsigned char greybits_done; - -} ColorProfile; - -static void color_profile_init(ColorProfile* profile, LodePNGColorMode* mode) -{ - profile->sixteenbit = 0; - profile->sixteenbit_done = mode->bitdepth == 16 ? 0 : 1; - - profile->colored = 0; - profile->colored_done = lodepng_is_greyscale_type(mode) ? 1 : 0; - - profile->key = 0; - profile->alpha = 0; - profile->alpha_done = lodepng_can_have_alpha(mode) ? 0 : 1; - - profile->numcolors = 0; - color_tree_init(&profile->tree, 1); - profile->palette = (unsigned char*)mymalloc(1024); - profile->maxnumcolors = 257; - if(lodepng_get_bpp(mode) <= 8) - { - int bpp = lodepng_get_bpp(mode); - profile->maxnumcolors = bpp == 1 ? 2 : (bpp == 2 ? 4 : (bpp == 4 ? 16 : 256)); - } - profile->numcolors_done = 0; - - profile->greybits = 1; - profile->greybits_done = lodepng_get_bpp(mode) == 1 ? 1 : 0; -} - -static void color_profile_cleanup(ColorProfile* profile) -{ - color_tree_cleanup(&profile->tree); - myfree(profile->palette); -} - -/*function used for debug purposes with C++*/ -/*void printColorProfile(ColorProfile* p) -{ - std::cout << "sixteenbit: " << (int)p->sixteenbit << std::endl; - std::cout << "sixteenbit_done: " << (int)p->sixteenbit_done << std::endl; - std::cout << "colored: " << (int)p->colored << std::endl; - std::cout << "colored_done: " << (int)p->colored_done << std::endl; - std::cout << "key: " << (int)p->key << std::endl; - std::cout << "key_r: " << (int)p->key_r << std::endl; - std::cout << "key_g: " << (int)p->key_g << std::endl; - std::cout << "key_b: " << (int)p->key_b << std::endl; - std::cout << "alpha: " << (int)p->alpha << std::endl; - std::cout << "alpha_done: " << (int)p->alpha_done << std::endl; - std::cout << "numcolors: " << (int)p->numcolors << std::endl; - std::cout << "maxnumcolors: " << (int)p->maxnumcolors << std::endl; - std::cout << "numcolors_done: " << (int)p->numcolors_done << std::endl; - std::cout << "greybits: " << (int)p->greybits << std::endl; - std::cout << "greybits_done: " << (int)p->greybits_done << std::endl; -}*/ - -/*Returns how many bits needed to represent given value (max 8 bit)*/ -unsigned getValueRequiredBits(unsigned char value) -{ - if(value == 0 || value == 255) return 1; - /*The scaling of 2-bit and 4-bit values uses multiples of 85 and 17*/ - if(value % 17 == 0) return value % 85 == 0 ? 2 : 4; - return 8; -} - -/*profile must already have been inited with mode. -It's ok to set some parameters of profile to done already.*/ -static unsigned get_color_profile(ColorProfile* profile, - const unsigned char* in, size_t numpixels, - LodePNGColorMode* mode) -{ - unsigned error = 0; - size_t i; - - if(mode->bitdepth == 16) - { - for(i = 0; i < numpixels; i++) - { - unsigned short r, g, b, a; - error = getPixelColorRGBA16(&r, &g, &b, &a, in, i, mode); - if(error) break; - - /*a color is considered good for 8-bit if the first byte and the second byte are equal, - (so if it's divisible through 257), NOT necessarily if the second byte is 0*/ - if(!profile->sixteenbit_done - && (((r & 255) != ((r >> 8) & 255)) - || ((g & 255) != ((g >> 8) & 255)) - || ((b & 255) != ((b >> 8) & 255)))) - { - profile->sixteenbit = 1; - profile->sixteenbit_done = 1; - profile->greybits_done = 1; /*greybits is not applicable anymore at 16-bit*/ - profile->numcolors_done = 1; /*counting colors no longer useful, palette doesn't support 16-bit*/ - } - - if(!profile->colored_done && (r != g || r != b)) - { - profile->colored = 1; - profile->colored_done = 1; - profile->greybits_done = 1; /*greybits is not applicable anymore*/ - } - - if(!profile->alpha_done && a != 255) - { - if(a == 0 && !(profile->key && (r != profile->key_r || g != profile->key_g || b != profile->key_b))) - { - if(!profile->key) - { - profile->key = 1; - profile->key_r = r; - profile->key_g = g; - profile->key_b = b; - } - } - else - { - profile->alpha = 1; - profile->alpha_done = 1; - profile->greybits_done = 1; /*greybits is not applicable anymore*/ - } - } - - if(!profile->greybits_done) - { - /*assuming 8-bit r, this test does not care about 16-bit*/ - unsigned bits = getValueRequiredBits(r); - if(bits > profile->greybits) profile->greybits = bits; - if(profile->greybits >= 8) profile->greybits_done = 1; - } - - if(!profile->numcolors_done) - { - /*assuming 8-bit rgba, this test does not care about 16-bit*/ - if(!color_tree_has(&profile->tree, r, g, b, a)) - { - color_tree_add(&profile->tree, r, g, b, a, profile->numcolors); - if(profile->numcolors < 256) - { - unsigned char* p = profile->palette; - unsigned i = profile->numcolors; - p[i * 4 + 0] = r; - p[i * 4 + 1] = g; - p[i * 4 + 2] = b; - p[i * 4 + 3] = a; - } - profile->numcolors++; - if(profile->numcolors >= profile->maxnumcolors) profile->numcolors_done = 1; - } - } - - if(profile->alpha_done && profile->numcolors_done - && profile->colored_done && profile->sixteenbit_done && profile->greybits_done) - { - break; - } - }; - } - else - { - for(i = 0; i < numpixels; i++) - { - unsigned char r, g, b, a; - error = getPixelColorRGBA8(&r, &g, &b, &a, in, i, mode); - if(error) break; - - if(!profile->colored_done && (r != g || r != b)) - { - profile->colored = 1; - profile->colored_done = 1; - profile->greybits_done = 1; /*greybits is not applicable anymore*/ - } - - if(!profile->alpha_done && a != 255) - { - if(a == 0 && !(profile->key && (r != profile->key_r || g != profile->key_g || b != profile->key_b))) - { - if(!profile->key) - { - profile->key = 1; - profile->key_r = r; - profile->key_g = g; - profile->key_b = b; - } - } - else - { - profile->alpha = 1; - profile->alpha_done = 1; - profile->greybits_done = 1; /*greybits is not applicable anymore*/ - } - } - - if(!profile->greybits_done) - { - unsigned bits = getValueRequiredBits(r); - if(bits > profile->greybits) profile->greybits = bits; - if(profile->greybits >= 8) profile->greybits_done = 1; - } - - if(!profile->numcolors_done) - { - if(!color_tree_has(&profile->tree, r, g, b, a)) - { - - color_tree_add(&profile->tree, r, g, b, a, profile->numcolors); - if(profile->numcolors < 256) - { - unsigned char* p = profile->palette; - unsigned i = profile->numcolors; - p[i * 4 + 0] = r; - p[i * 4 + 1] = g; - p[i * 4 + 2] = b; - p[i * 4 + 3] = a; - } - profile->numcolors++; - if(profile->numcolors >= profile->maxnumcolors) profile->numcolors_done = 1; - } - } - - if(profile->alpha_done && profile->numcolors_done && profile->colored_done && profile->greybits_done) - { - break; - } - }; - } - - /*make the profile's key always 16-bit for consistency*/ - if(mode->bitdepth < 16) - { - /*repeat each byte twice*/ - profile->key_r *= 257; - profile->key_g *= 257; - profile->key_b *= 257; - } - - return error; -} - -/*updates values of mode with a potentially smaller color model. mode_out should -contain the user chosen color model, but will be overwritten with the new chosen one.*/ -static unsigned doAutoChooseColor(LodePNGColorMode* mode_out, - const unsigned char* image, unsigned w, unsigned h, LodePNGColorMode* mode_in, - LodePNGAutoConvert auto_convert) -{ - ColorProfile profile; - unsigned error = 0; - - if(auto_convert == LAC_ALPHA) - { - if(mode_out->colortype != LCT_RGBA && mode_out->colortype != LCT_GREY_ALPHA) return 0; - } - - color_profile_init(&profile, mode_in); - if(auto_convert == LAC_ALPHA) - { - profile.colored_done = 1; - profile.greybits_done = 1; - profile.numcolors_done = 1; - profile.sixteenbit_done = 1; - } - error = get_color_profile(&profile, image, w * h, mode_in); - - if(!error && auto_convert == LAC_ALPHA) - { - if(!profile.alpha) - { - mode_out->colortype = (mode_out->colortype == LCT_RGBA ? LCT_RGB : LCT_GREY); - } - } - else if(!error && auto_convert != LAC_ALPHA) - { - mode_out->key_defined = 0; - - if(profile.sixteenbit) - { - mode_out->bitdepth = 16; - if(profile.alpha) - { - mode_out->colortype = profile.colored ? LCT_RGBA : LCT_GREY_ALPHA; - } - else - { - mode_out->colortype = profile.colored ? LCT_RGB : LCT_GREY; - if(profile.key) - { - mode_out->key_defined = 1; - mode_out->key_r = profile.key_r; - mode_out->key_g = profile.key_g; - mode_out->key_b = profile.key_b; - } - } - } - else /*less than 16 bits per channel*/ - { - /*don't add palette overhead if image hasn't got a lot of pixels*/ - unsigned n = profile.numcolors; - int palette_ok = n <= 256 && (n * 2 < w * h); - unsigned palettebits = n <= 2 ? 1 : (n <= 4 ? 2 : (n <= 16 ? 4 : 8)); - int grey_ok = !profile.colored && !profile.alpha; /*grey without alpha, with potentially low bits*/ - if(palette_ok || grey_ok) - { - if(!palette_ok || (grey_ok && profile.greybits <= palettebits)) - { - mode_out->colortype = LCT_GREY; - mode_out->bitdepth = profile.greybits; - if(profile.key) - { - unsigned keyval = profile.key_r; - keyval &= (profile.greybits - 1); /*same subgroup of bits repeated, so taking right bits is fine*/ - mode_out->key_defined = 1; - mode_out->key_r = keyval; - mode_out->key_g = keyval; - mode_out->key_b = keyval; - } - } - else - { - /*fill in the palette*/ - unsigned i; - unsigned char* p = profile.palette; - for(i = 0; i < profile.numcolors; i++) - { - error = lodepng_palette_add(mode_out, p[i * 4 + 0], p[i * 4 + 1], p[i * 4 + 2], p[i * 4 + 3]); - if(error) break; - } - - mode_out->colortype = LCT_PALETTE; - mode_out->bitdepth = palettebits; - } - } - else /*8-bit per channel*/ - { - mode_out->bitdepth = 8; - if(profile.alpha) - { - mode_out->colortype = profile.colored ? LCT_RGBA : LCT_GREY_ALPHA; - } - else - { - mode_out->colortype = profile.colored ? LCT_RGB : LCT_GREY /*LCT_GREY normally won't occur, already done earlier*/; - if(profile.key) - { - mode_out->key_defined = 1; - mode_out->key_r = profile.key_r % 256; - mode_out->key_g = profile.key_g % 256; - mode_out->key_b = profile.key_b % 256; - } - } - } - } - } - - color_profile_cleanup(&profile); - - if(mode_out->colortype == LCT_PALETTE && mode_in->palettesize == mode_out->palettesize) - { - /*In this case keep the palette order of the input, so that the user can choose an optimal one*/ - size_t i; - for(i = 0; i < mode_in->palettesize * 4; i++) - { - mode_out->palette[i] = mode_in->palette[i]; - } - } - - if(auto_convert == LAC_AUTO_NO_NIBBLES && mode_out->bitdepth < 8) - { - /*palette can keep its small amount of colors, as long as no indices use it*/ - mode_out->bitdepth = 8; - } - - return error; -} - -#endif /* #ifdef LODEPNG_COMPILE_ENCODER */ - -/* -Paeth predicter, used by PNG filter type 4 -The parameters are of type short, but should come from unsigned chars, the shorts -are only needed to make the paeth calculation correct. -*/ -static unsigned char paethPredictor(short a, short b, short c) -{ - short pa = abs(b - c); - short pb = abs(a - c); - short pc = abs(a + b - c - c); - - if(pc < pa && pc < pb) return (unsigned char)c; - else if(pb < pa) return (unsigned char)b; - else return (unsigned char)a; -} - -/*shared values used by multiple Adam7 related functions*/ - -static const unsigned ADAM7_IX[7] = { 0, 4, 0, 2, 0, 1, 0 }; /*x start values*/ -static const unsigned ADAM7_IY[7] = { 0, 0, 4, 0, 2, 0, 1 }; /*y start values*/ -static const unsigned ADAM7_DX[7] = { 8, 8, 4, 4, 2, 2, 1 }; /*x delta values*/ -static const unsigned ADAM7_DY[7] = { 8, 8, 8, 4, 4, 2, 2 }; /*y delta values*/ - -static void Adam7_getpassvalues(unsigned passw[7], unsigned passh[7], size_t filter_passstart[8], - size_t padded_passstart[8], size_t passstart[8], unsigned w, unsigned h, unsigned bpp) -{ - /*the passstart values have 8 values: the 8th one indicates the byte after the end of the 7th (= last) pass*/ - unsigned i; - - /*calculate width and height in pixels of each pass*/ - for(i = 0; i < 7; i++) - { - passw[i] = (w + ADAM7_DX[i] - ADAM7_IX[i] - 1) / ADAM7_DX[i]; - passh[i] = (h + ADAM7_DY[i] - ADAM7_IY[i] - 1) / ADAM7_DY[i]; - if(passw[i] == 0) passh[i] = 0; - if(passh[i] == 0) passw[i] = 0; - } - - filter_passstart[0] = padded_passstart[0] = passstart[0] = 0; - for(i = 0; i < 7; i++) - { - /*if passw[i] is 0, it's 0 bytes, not 1 (no filtertype-byte)*/ - filter_passstart[i + 1] = filter_passstart[i] - + ((passw[i] && passh[i]) ? passh[i] * (1 + (passw[i] * bpp + 7) / 8) : 0); - /*bits padded if needed to fill full byte at end of each scanline*/ - padded_passstart[i + 1] = padded_passstart[i] + passh[i] * ((passw[i] * bpp + 7) / 8); - /*only padded at end of reduced image*/ - passstart[i + 1] = passstart[i] + (passh[i] * passw[i] * bpp + 7) / 8; - } -} - -#ifdef LODEPNG_COMPILE_DECODER - -/* ////////////////////////////////////////////////////////////////////////// */ -/* / PNG Decoder / */ -/* ////////////////////////////////////////////////////////////////////////// */ - -/*read the information from the header and store it in the LodePNGInfo. return value is error*/ -unsigned lodepng_inspect(unsigned* w, unsigned* h, LodePNGState* state, - const unsigned char* in, size_t insize) -{ - LodePNGInfo* info = &state->info_png; - if(insize == 0 || in == 0) - { - CERROR_RETURN_ERROR(state->error, 48); /*error: the given data is empty*/ - } - if(insize < 29) - { - CERROR_RETURN_ERROR(state->error, 27); /*error: the data length is smaller than the length of a PNG header*/ - } - - /*when decoding a new PNG image, make sure all parameters created after previous decoding are reset*/ - lodepng_info_cleanup(info); - lodepng_info_init(info); - - if(in[0] != 137 || in[1] != 80 || in[2] != 78 || in[3] != 71 - || in[4] != 13 || in[5] != 10 || in[6] != 26 || in[7] != 10) - { - CERROR_RETURN_ERROR(state->error, 28); /*error: the first 8 bytes are not the correct PNG signature*/ - } - if(in[12] != 'I' || in[13] != 'H' || in[14] != 'D' || in[15] != 'R') - { - CERROR_RETURN_ERROR(state->error, 29); /*error: it doesn't start with a IHDR chunk!*/ - } - - /*read the values given in the header*/ - *w = lodepng_read32bitInt(&in[16]); - *h = lodepng_read32bitInt(&in[20]); - info->color.bitdepth = in[24]; - info->color.colortype = (LodePNGColorType)in[25]; - info->compression_method = in[26]; - info->filter_method = in[27]; - info->interlace_method = in[28]; - - if(!state->decoder.ignore_crc) - { - unsigned CRC = lodepng_read32bitInt(&in[29]); - unsigned checksum = lodepng_crc32(&in[12], 17); - if(CRC != checksum) - { - CERROR_RETURN_ERROR(state->error, 57); /*invalid CRC*/ - } - } - - /*error: only compression method 0 is allowed in the specification*/ - if(info->compression_method != 0) CERROR_RETURN_ERROR(state->error, 32); - /*error: only filter method 0 is allowed in the specification*/ - if(info->filter_method != 0) CERROR_RETURN_ERROR(state->error, 33); - /*error: only interlace methods 0 and 1 exist in the specification*/ - if(info->interlace_method > 1) CERROR_RETURN_ERROR(state->error, 34); - - state->error = checkColorValidity(info->color.colortype, info->color.bitdepth); - return state->error; -} - -static unsigned unfilterScanline(unsigned char* recon, const unsigned char* scanline, const unsigned char* precon, - size_t bytewidth, unsigned char filterType, size_t length) -{ - /* - For PNG filter method 0 - unfilter a PNG image scanline by scanline. when the pixels are smaller than 1 byte, - the filter works byte per byte (bytewidth = 1) - precon is the previous unfiltered scanline, recon the result, scanline the current one - the incoming scanlines do NOT include the filtertype byte, that one is given in the parameter filterType instead - recon and scanline MAY be the same memory address! precon must be disjoint. - */ - - size_t i; - switch(filterType) - { - case 0: - for(i = 0; i < length; i++) recon[i] = scanline[i]; - break; - case 1: - for(i = 0; i < bytewidth; i++) recon[i] = scanline[i]; - for(i = bytewidth; i < length; i++) recon[i] = scanline[i] + recon[i - bytewidth]; - break; - case 2: - if(precon) - { - for(i = 0; i < length; i++) recon[i] = scanline[i] + precon[i]; - } - else - { - for(i = 0; i < length; i++) recon[i] = scanline[i]; - } - break; - case 3: - if(precon) - { - for(i = 0; i < bytewidth; i++) recon[i] = scanline[i] + precon[i] / 2; - for(i = bytewidth; i < length; i++) recon[i] = scanline[i] + ((recon[i - bytewidth] + precon[i]) / 2); - } - else - { - for(i = 0; i < bytewidth; i++) recon[i] = scanline[i]; - for(i = bytewidth; i < length; i++) recon[i] = scanline[i] + recon[i - bytewidth] / 2; - } - break; - case 4: - if(precon) - { - for(i = 0; i < bytewidth; i++) - { - recon[i] = (scanline[i] + precon[i]); /*paethPredictor(0, precon[i], 0) is always precon[i]*/ - } - for(i = bytewidth; i < length; i++) - { - recon[i] = (scanline[i] + paethPredictor(recon[i - bytewidth], precon[i], precon[i - bytewidth])); - } - } - else - { - for(i = 0; i < bytewidth; i++) - { - recon[i] = scanline[i]; - } - for(i = bytewidth; i < length; i++) - { - /*paethPredictor(recon[i - bytewidth], 0, 0) is always recon[i - bytewidth]*/ - recon[i] = (scanline[i] + recon[i - bytewidth]); - } - } - break; - default: return 36; /*error: unexisting filter type given*/ - } - return 0; -} - -static unsigned unfilter(unsigned char* out, const unsigned char* in, unsigned w, unsigned h, unsigned bpp) -{ - /* - For PNG filter method 0 - this function unfilters a single image (e.g. without interlacing this is called once, with Adam7 seven times) - out must have enough bytes allocated already, in must have the scanlines + 1 filtertype byte per scanline - w and h are image dimensions or dimensions of reduced image, bpp is bits per pixel - in and out are allowed to be the same memory address (but aren't the same size since in has the extra filter bytes) - */ - - unsigned y; - unsigned char* prevline = 0; - - /*bytewidth is used for filtering, is 1 when bpp < 8, number of bytes per pixel otherwise*/ - size_t bytewidth = (bpp + 7) / 8; - size_t linebytes = (w * bpp + 7) / 8; - - for(y = 0; y < h; y++) - { - size_t outindex = linebytes * y; - size_t inindex = (1 + linebytes) * y; /*the extra filterbyte added to each row*/ - unsigned char filterType = in[inindex]; - - CERROR_TRY_RETURN(unfilterScanline(&out[outindex], &in[inindex + 1], prevline, bytewidth, filterType, linebytes)); - - prevline = &out[outindex]; - } - - return 0; -} - -static void Adam7_deinterlace(unsigned char* out, const unsigned char* in, unsigned w, unsigned h, unsigned bpp) -{ - /*Note: this function works on image buffers WITHOUT padding bits at end of scanlines - with non-multiple-of-8 bit amounts, only between reduced images is padding - out must be big enough AND must be 0 everywhere if bpp < 8 in the current implementation - (because that's likely a little bit faster)*/ - unsigned passw[7], passh[7]; - size_t filter_passstart[8], padded_passstart[8], passstart[8]; - unsigned i; - - Adam7_getpassvalues(passw, passh, filter_passstart, padded_passstart, passstart, w, h, bpp); - - if(bpp >= 8) - { - for(i = 0; i < 7; i++) - { - unsigned x, y, b; - size_t bytewidth = bpp / 8; - for(y = 0; y < passh[i]; y++) - for(x = 0; x < passw[i]; x++) - { - size_t pixelinstart = passstart[i] + (y * passw[i] + x) * bytewidth; - size_t pixeloutstart = ((ADAM7_IY[i] + y * ADAM7_DY[i]) * w + ADAM7_IX[i] + x * ADAM7_DX[i]) * bytewidth; - for(b = 0; b < bytewidth; b++) - { - out[pixeloutstart + b] = in[pixelinstart + b]; - } - } - } - } - else /*bpp < 8: Adam7 with pixels < 8 bit is a bit trickier: with bit pointers*/ - { - for(i = 0; i < 7; i++) - { - unsigned x, y, b; - unsigned ilinebits = bpp * passw[i]; - unsigned olinebits = bpp * w; - size_t obp, ibp; /*bit pointers (for out and in buffer)*/ - for(y = 0; y < passh[i]; y++) - for(x = 0; x < passw[i]; x++) - { - ibp = (8 * passstart[i]) + (y * ilinebits + x * bpp); - obp = (ADAM7_IY[i] + y * ADAM7_DY[i]) * olinebits + (ADAM7_IX[i] + x * ADAM7_DX[i]) * bpp; - for(b = 0; b < bpp; b++) - { - unsigned char bit = readBitFromReversedStream(&ibp, in); - /*note that this function assumes the out buffer is completely 0, use setBitOfReversedStream otherwise*/ - setBitOfReversedStream0(&obp, out, bit); - } - } - } - } -} - -static void removePaddingBits(unsigned char* out, const unsigned char* in, - size_t olinebits, size_t ilinebits, unsigned h) -{ - /* - After filtering there are still padding bits if scanlines have non multiple of 8 bit amounts. They need - to be removed (except at last scanline of (Adam7-reduced) image) before working with pure image buffers - for the Adam7 code, the color convert code and the output to the user. - in and out are allowed to be the same buffer, in may also be higher but still overlapping; in must - have >= ilinebits*h bits, out must have >= olinebits*h bits, olinebits must be <= ilinebits - also used to move bits after earlier such operations happened, e.g. in a sequence of reduced images from Adam7 - only useful if (ilinebits - olinebits) is a value in the range 1..7 - */ - unsigned y; - size_t diff = ilinebits - olinebits; - size_t ibp = 0, obp = 0; /*input and output bit pointers*/ - for(y = 0; y < h; y++) - { - size_t x; - for(x = 0; x < olinebits; x++) - { - unsigned char bit = readBitFromReversedStream(&ibp, in); - setBitOfReversedStream(&obp, out, bit); - } - ibp += diff; - } -} - -/*out must be buffer big enough to contain full image, and in must contain the full decompressed data from -the IDAT chunks (with filter index bytes and possible padding bits) -return value is error*/ -static unsigned postProcessScanlines(unsigned char* out, unsigned char* in, - unsigned w, unsigned h, const LodePNGInfo* info_png) -{ - /* - This function converts the filtered-padded-interlaced data into pure 2D image buffer with the PNG's colortype. - Steps: - *) if no Adam7: 1) unfilter 2) remove padding bits (= posible extra bits per scanline if bpp < 8) - *) if adam7: 1) 7x unfilter 2) 7x remove padding bits 3) Adam7_deinterlace - NOTE: the in buffer will be overwritten with intermediate data! - */ - unsigned bpp = lodepng_get_bpp(&info_png->color); - if(bpp == 0) return 31; /*error: invalid colortype*/ - - if(info_png->interlace_method == 0) - { - if(bpp < 8 && w * bpp != ((w * bpp + 7) / 8) * 8) - { - CERROR_TRY_RETURN(unfilter(in, in, w, h, bpp)); - removePaddingBits(out, in, w * bpp, ((w * bpp + 7) / 8) * 8, h); - } - /*we can immediatly filter into the out buffer, no other steps needed*/ - else CERROR_TRY_RETURN(unfilter(out, in, w, h, bpp)); - } - else /*interlace_method is 1 (Adam7)*/ - { - unsigned passw[7], passh[7]; size_t filter_passstart[8], padded_passstart[8], passstart[8]; - unsigned i; - - Adam7_getpassvalues(passw, passh, filter_passstart, padded_passstart, passstart, w, h, bpp); - - for(i = 0; i < 7; i++) - { - CERROR_TRY_RETURN(unfilter(&in[padded_passstart[i]], &in[filter_passstart[i]], passw[i], passh[i], bpp)); - /*TODO: possible efficiency improvement: if in this reduced image the bits fit nicely in 1 scanline, - move bytes instead of bits or move not at all*/ - if(bpp < 8) - { - /*remove padding bits in scanlines; after this there still may be padding - bits between the different reduced images: each reduced image still starts nicely at a byte*/ - removePaddingBits(&in[passstart[i]], &in[padded_passstart[i]], passw[i] * bpp, - ((passw[i] * bpp + 7) / 8) * 8, passh[i]); - } - } - - Adam7_deinterlace(out, in, w, h, bpp); - } - - return 0; -} - -/*read a PNG, the result will be in the same color type as the PNG (hence "generic")*/ -static void decodeGeneric(unsigned char** out, unsigned* w, unsigned* h, - LodePNGState* state, - const unsigned char* in, size_t insize) -{ - unsigned char IEND = 0; - const unsigned char* chunk; - size_t i; - ucvector idat; /*the data from idat chunks*/ - - /*for unknown chunk order*/ - unsigned unknown = 0; -#ifdef LODEPNG_COMPILE_ANCILLARY_CHUNKS - unsigned critical_pos = 1; /*1 = after IHDR, 2 = after PLTE, 3 = after IDAT*/ -#endif /*LODEPNG_COMPILE_ANCILLARY_CHUNKS*/ - - /*provide some proper output values if error will happen*/ - *out = 0; - - state->error = lodepng_inspect(w, h, state, in, insize); /*reads header and resets other parameters in state->info_png*/ - if(state->error) return; - - ucvector_init(&idat); - chunk = &in[33]; /*first byte of the first chunk after the header*/ - - /*loop through the chunks, ignoring unknown chunks and stopping at IEND chunk. - IDAT data is put at the start of the in buffer*/ - while(!IEND && !state->error) - { - unsigned chunkLength; - const unsigned char* data; /*the data in the chunk*/ - - /*error: size of the in buffer too small to contain next chunk*/ - if((size_t)((chunk - in) + 12) > insize || chunk < in) CERROR_BREAK(state->error, 30); - - /*length of the data of the chunk, excluding the length bytes, chunk type and CRC bytes*/ - chunkLength = lodepng_chunk_length(chunk); - /*error: chunk length larger than the max PNG chunk size*/ - if(chunkLength > 2147483647) CERROR_BREAK(state->error, 63); - - if((size_t)((chunk - in) + chunkLength + 12) > insize || (chunk + chunkLength + 12) < in) - { - CERROR_BREAK(state->error, 64); /*error: size of the in buffer too small to contain next chunk*/ - } - - data = lodepng_chunk_data_const(chunk); - - /*IDAT chunk, containing compressed image data*/ - if(lodepng_chunk_type_equals(chunk, "IDAT")) - { - size_t oldsize = idat.size; - if(!ucvector_resize(&idat, oldsize + chunkLength)) CERROR_BREAK(state->error, 83 /*alloc fail*/); - for(i = 0; i < chunkLength; i++) idat.data[oldsize + i] = data[i]; -#ifdef LODEPNG_COMPILE_ANCILLARY_CHUNKS - critical_pos = 3; -#endif /*LODEPNG_COMPILE_ANCILLARY_CHUNKS*/ - } - /*IEND chunk*/ - else if(lodepng_chunk_type_equals(chunk, "IEND")) - { - IEND = 1; - } - /*palette chunk (PLTE)*/ - else if(lodepng_chunk_type_equals(chunk, "PLTE")) - { - unsigned pos = 0; - if(state->info_png.color.palette) myfree(state->info_png.color.palette); - state->info_png.color.palettesize = chunkLength / 3; - state->info_png.color.palette = (unsigned char*)mymalloc(4 * state->info_png.color.palettesize); - if(!state->info_png.color.palette && state->info_png.color.palettesize) - { - state->info_png.color.palettesize = 0; - CERROR_BREAK(state->error, 83); /*alloc fail*/ - } - if(state->info_png.color.palettesize > 256) CERROR_BREAK(state->error, 38); /*error: palette too big*/ - - for(i = 0; i < state->info_png.color.palettesize; i++) - { - state->info_png.color.palette[4 * i + 0] = data[pos++]; /*R*/ - state->info_png.color.palette[4 * i + 1] = data[pos++]; /*G*/ - state->info_png.color.palette[4 * i + 2] = data[pos++]; /*B*/ - state->info_png.color.palette[4 * i + 3] = 255; /*alpha*/ - } -#ifdef LODEPNG_COMPILE_ANCILLARY_CHUNKS - critical_pos = 2; -#endif /*LODEPNG_COMPILE_ANCILLARY_CHUNKS*/ - } - /*palette transparency chunk (tRNS)*/ - else if(lodepng_chunk_type_equals(chunk, "tRNS")) - { - if(state->info_png.color.colortype == LCT_PALETTE) - { - /*error: more alpha values given than there are palette entries*/ - if(chunkLength > state->info_png.color.palettesize) CERROR_BREAK(state->error, 38); - - for(i = 0; i < chunkLength; i++) state->info_png.color.palette[4 * i + 3] = data[i]; - } - else if(state->info_png.color.colortype == LCT_GREY) - { - /*error: this chunk must be 2 bytes for greyscale image*/ - if(chunkLength != 2) CERROR_BREAK(state->error, 30); - - state->info_png.color.key_defined = 1; - state->info_png.color.key_r = state->info_png.color.key_g - = state->info_png.color.key_b = 256 * data[0] + data[1]; - } - else if(state->info_png.color.colortype == LCT_RGB) - { - /*error: this chunk must be 6 bytes for RGB image*/ - if(chunkLength != 6) CERROR_BREAK(state->error, 41); - - state->info_png.color.key_defined = 1; - state->info_png.color.key_r = 256 * data[0] + data[1]; - state->info_png.color.key_g = 256 * data[2] + data[3]; - state->info_png.color.key_b = 256 * data[4] + data[5]; - } - else CERROR_BREAK(state->error, 42); /*error: tRNS chunk not allowed for other color models*/ - } -#ifdef LODEPNG_COMPILE_ANCILLARY_CHUNKS - /*background color chunk (bKGD)*/ - else if(lodepng_chunk_type_equals(chunk, "bKGD")) - { - if(state->info_png.color.colortype == LCT_PALETTE) - { - /*error: this chunk must be 1 byte for indexed color image*/ - if(chunkLength != 1) CERROR_BREAK(state->error, 43); - - state->info_png.background_defined = 1; - state->info_png.background_r = state->info_png.background_g = state->info_png.background_b = data[0]; - } - else if(state->info_png.color.colortype == LCT_GREY || state->info_png.color.colortype == LCT_GREY_ALPHA) - { - /*error: this chunk must be 2 bytes for greyscale image*/ - if(chunkLength != 2) CERROR_BREAK(state->error, 44); - - state->info_png.background_defined = 1; - state->info_png.background_r = state->info_png.background_g = state->info_png.background_b - = 256 * data[0] + data[1]; - } - else if(state->info_png.color.colortype == LCT_RGB || state->info_png.color.colortype == LCT_RGBA) - { - /*error: this chunk must be 6 bytes for greyscale image*/ - if(chunkLength != 6) CERROR_BREAK(state->error, 45); - - state->info_png.background_defined = 1; - state->info_png.background_r = 256 * data[0] + data[1]; - state->info_png.background_g = 256 * data[2] + data[3]; - state->info_png.background_b = 256 * data[4] + data[5]; - } - } - /*text chunk (tEXt)*/ - else if(lodepng_chunk_type_equals(chunk, "tEXt")) - { - if(state->decoder.read_text_chunks) - { - char *key = 0, *str = 0; - - while(!state->error) /*not really a while loop, only used to break on error*/ - { - unsigned length, string2_begin; - - length = 0; - while(length < chunkLength && data[length] != 0) length++; - /*error, end reached, no null terminator?*/ - if(length + 1 >= chunkLength) CERROR_BREAK(state->error, 75); - - key = (char*)mymalloc(length + 1); - if(!key) CERROR_BREAK(state->error, 83); /*alloc fail*/ - - key[length] = 0; - for(i = 0; i < length; i++) key[i] = data[i]; - - string2_begin = length + 1; - /*error, end reached, no null terminator?*/ - if(string2_begin > chunkLength) CERROR_BREAK(state->error, 75); - - length = chunkLength - string2_begin; - str = (char*)mymalloc(length + 1); - if(!str) CERROR_BREAK(state->error, 83); /*alloc fail*/ - - str[length] = 0; - for(i = 0; i < length; i++) str[i] = data[string2_begin + i]; - - state->error = lodepng_add_text(&state->info_png, key, str); - - break; - } - - myfree(key); - myfree(str); - } - } - /*compressed text chunk (zTXt)*/ - else if(lodepng_chunk_type_equals(chunk, "zTXt")) - { - if(state->decoder.read_text_chunks) - { - unsigned length, string2_begin; - char *key = 0; - ucvector decoded; - - ucvector_init(&decoded); - - while(!state->error) /*not really a while loop, only used to break on error*/ - { - for(length = 0; length < chunkLength && data[length] != 0; length++) ; - if(length + 2 >= chunkLength) CERROR_BREAK(state->error, 75); /*no null termination, corrupt?*/ - - key = (char*)mymalloc(length + 1); - if(!key) CERROR_BREAK(state->error, 83); /*alloc fail*/ - - key[length] = 0; - for(i = 0; i < length; i++) key[i] = data[i]; - - if(data[length + 1] != 0) CERROR_BREAK(state->error, 72); /*the 0 byte indicating compression must be 0*/ - - string2_begin = length + 2; - if(string2_begin > chunkLength) CERROR_BREAK(state->error, 75); /*no null termination, corrupt?*/ - - length = chunkLength - string2_begin; - state->error = lodepng_zlib_decompress(&decoded.data, &decoded.size, - (unsigned char*)(&data[string2_begin]), - length, &state->decoder.zlibsettings); - if(state->error) break; - ucvector_push_back(&decoded, 0); - - state->error = lodepng_add_text(&state->info_png, key, (char*)decoded.data); - - break; - } - - myfree(key); - ucvector_cleanup(&decoded); - if(state->error) break; - } - } - /*international text chunk (iTXt)*/ - else if(lodepng_chunk_type_equals(chunk, "iTXt")) - { - if(state->decoder.read_text_chunks) - { - unsigned length, begin, compressed; - char *key = 0, *langtag = 0, *transkey = 0; - ucvector decoded; - ucvector_init(&decoded); - - while(!state->error) /*not really a while loop, only used to break on error*/ - { - /*Quick check if the chunk length isn't too small. Even without check - it'd still fail with other error checks below if it's too short. This just gives a different error code.*/ - if(chunkLength < 5) CERROR_BREAK(state->error, 30); /*iTXt chunk too short*/ - - /*read the key*/ - for(length = 0; length < chunkLength && data[length] != 0; length++) ; - if(length + 2 >= chunkLength) CERROR_BREAK(state->error, 75); /*no null termination char found*/ - - key = (char*)mymalloc(length + 1); - if(!key) CERROR_BREAK(state->error, 83); /*alloc fail*/ - - key[length] = 0; - for(i = 0; i < length; i++) key[i] = data[i]; - - /*read the compression method*/ - compressed = data[length + 1]; - if(data[length + 2] != 0) CERROR_BREAK(state->error, 72); /*the 0 byte indicating compression must be 0*/ - - /*read the langtag*/ - begin = length + 3; - length = 0; - for(i = begin; i < chunkLength && data[i] != 0; i++) length++; - if(begin + length + 1 >= chunkLength) CERROR_BREAK(state->error, 75); /*no null termination char found*/ - - langtag = (char*)mymalloc(length + 1); - if(!langtag) CERROR_BREAK(state->error, 83); /*alloc fail*/ - - langtag[length] = 0; - for(i = 0; i < length; i++) langtag[i] = data[begin + i]; - - /*read the transkey*/ - begin += length + 1; - length = 0; - for(i = begin; i < chunkLength && data[i] != 0; i++) length++; - if(begin + length + 1 >= chunkLength) CERROR_BREAK(state->error, 75); /*no null termination, corrupt?*/ - - transkey = (char*)mymalloc(length + 1); - if(!transkey) CERROR_BREAK(state->error, 83); /*alloc fail*/ - - transkey[length] = 0; - for(i = 0; i < length; i++) transkey[i] = data[begin + i]; - - /*read the actual text*/ - begin += length + 1; - if(begin > chunkLength) CERROR_BREAK(state->error, 75); /*no null termination, corrupt?*/ - - length = chunkLength - begin; - - if(compressed) - { - state->error = lodepng_zlib_decompress(&decoded.data, &decoded.size, - (unsigned char*)(&data[begin]), - length, &state->decoder.zlibsettings); - if(state->error) break; - if(decoded.allocsize < decoded.size) decoded.allocsize = decoded.size; - ucvector_push_back(&decoded, 0); - } - else - { - if(!ucvector_resize(&decoded, length + 1)) CERROR_BREAK(state->error, 83 /*alloc fail*/); - - decoded.data[length] = 0; - for(i = 0; i < length; i++) decoded.data[i] = data[begin + i]; - } - - state->error = lodepng_add_itext(&state->info_png, key, langtag, transkey, (char*)decoded.data); - - break; - } - - myfree(key); - myfree(langtag); - myfree(transkey); - ucvector_cleanup(&decoded); - if(state->error) break; - } - } - else if(lodepng_chunk_type_equals(chunk, "tIME")) - { - if(chunkLength != 7) CERROR_BREAK(state->error, 73); /*invalid tIME chunk size*/ - - state->info_png.time_defined = 1; - state->info_png.time.year = 256 * data[0] + data[+ 1]; - state->info_png.time.month = data[2]; - state->info_png.time.day = data[3]; - state->info_png.time.hour = data[4]; - state->info_png.time.minute = data[5]; - state->info_png.time.second = data[6]; - } - else if(lodepng_chunk_type_equals(chunk, "pHYs")) - { - if(chunkLength != 9) CERROR_BREAK(state->error, 74); /*invalid pHYs chunk size*/ - - state->info_png.phys_defined = 1; - state->info_png.phys_x = 16777216 * data[0] + 65536 * data[1] + 256 * data[2] + data[3]; - state->info_png.phys_y = 16777216 * data[4] + 65536 * data[5] + 256 * data[6] + data[7]; - state->info_png.phys_unit = data[8]; - } -#endif /*LODEPNG_COMPILE_ANCILLARY_CHUNKS*/ - else /*it's not an implemented chunk type, so ignore it: skip over the data*/ - { - /*error: unknown critical chunk (5th bit of first byte of chunk type is 0)*/ - if(!lodepng_chunk_ancillary(chunk)) CERROR_BREAK(state->error, 69); - - unknown = 1; -#ifdef LODEPNG_COMPILE_ANCILLARY_CHUNKS - if(state->decoder.remember_unknown_chunks) - { - state->error = lodepng_chunk_append(&state->info_png.unknown_chunks_data[critical_pos - 1], - &state->info_png.unknown_chunks_size[critical_pos - 1], chunk); - if(state->error) break; - } -#endif /*LODEPNG_COMPILE_ANCILLARY_CHUNKS*/ - } - - if(!state->decoder.ignore_crc && !unknown) /*check CRC if wanted, only on known chunk types*/ - { - if(lodepng_chunk_check_crc(chunk)) CERROR_BREAK(state->error, 57); /*invalid CRC*/ - } - - if(!IEND) chunk = lodepng_chunk_next_const(chunk); - } - - if(!state->error) - { - ucvector scanlines; - ucvector_init(&scanlines); - - /*maximum final image length is already reserved in the vector's length - this is not really necessary*/ - if(!ucvector_resize(&scanlines, lodepng_get_raw_size(*w, *h, &state->info_png.color) + *h)) - { - state->error = 83; /*alloc fail*/ - } - if(!state->error) - { - /*decompress with the Zlib decompressor*/ - state->error = lodepng_zlib_decompress(&scanlines.data, &scanlines.size, idat.data, - idat.size, &state->decoder.zlibsettings); - } - - if(!state->error) - { - ucvector outv; - ucvector_init(&outv); - if(!ucvector_resizev(&outv, - lodepng_get_raw_size(*w, *h, &state->info_png.color), 0)) state->error = 83; /*alloc fail*/ - if(!state->error) state->error = postProcessScanlines(outv.data, scanlines.data, *w, *h, &state->info_png); - *out = outv.data; - } - ucvector_cleanup(&scanlines); - } - - ucvector_cleanup(&idat); -} - -unsigned lodepng_decode(unsigned char** out, unsigned* w, unsigned* h, - LodePNGState* state, - const unsigned char* in, size_t insize) -{ - *out = 0; - decodeGeneric(out, w, h, state, in, insize); - if(state->error) return state->error; - if(!state->decoder.color_convert || lodepng_color_mode_equal(&state->info_raw, &state->info_png.color)) - { - /*same color type, no copying or converting of data needed*/ - /*store the info_png color settings on the info_raw so that the info_raw still reflects what colortype - the raw image has to the end user*/ - if(!state->decoder.color_convert) - { - state->error = lodepng_color_mode_copy(&state->info_raw, &state->info_png.color); - if(state->error) return state->error; - } - } - else - { - /*color conversion needed; sort of copy of the data*/ - unsigned char* data = *out; - size_t outsize; - - /*TODO: check if this works according to the statement in the documentation: "The converter can convert - from greyscale input color type, to 8-bit greyscale or greyscale with alpha"*/ - if(!(state->info_raw.colortype == LCT_RGB || state->info_raw.colortype == LCT_RGBA) - && !(state->info_raw.bitdepth == 8)) - { - return 56; /*unsupported color mode conversion*/ - } - - outsize = lodepng_get_raw_size(*w, *h, &state->info_raw); - *out = (unsigned char*)mymalloc(outsize); - if(!(*out)) - { - state->error = 83; /*alloc fail*/ - } - else state->error = lodepng_convert(*out, data, &state->info_raw, &state->info_png.color, *w, *h); - myfree(data); - } - return state->error; -} - -unsigned lodepng_decode_memory(unsigned char** out, unsigned* w, unsigned* h, const unsigned char* in, - size_t insize, LodePNGColorType colortype, unsigned bitdepth) -{ - unsigned error; - LodePNGState state; - lodepng_state_init(&state); - state.info_raw.colortype = colortype; - state.info_raw.bitdepth = bitdepth; - error = lodepng_decode(out, w, h, &state, in, insize); - lodepng_state_cleanup(&state); - return error; -} - -unsigned lodepng_decode32(unsigned char** out, unsigned* w, unsigned* h, const unsigned char* in, size_t insize) -{ - return lodepng_decode_memory(out, w, h, in, insize, LCT_RGBA, 8); -} - -unsigned lodepng_decode24(unsigned char** out, unsigned* w, unsigned* h, const unsigned char* in, size_t insize) -{ - return lodepng_decode_memory(out, w, h, in, insize, LCT_RGB, 8); -} - -#ifdef LODEPNG_COMPILE_DISK -unsigned lodepng_decode_file(unsigned char** out, unsigned* w, unsigned* h, const char* filename, - LodePNGColorType colortype, unsigned bitdepth) -{ - unsigned char* buffer; - size_t buffersize; - unsigned error; - error = lodepng_load_file(&buffer, &buffersize, filename); - if(!error) error = lodepng_decode_memory(out, w, h, buffer, buffersize, colortype, bitdepth); - myfree(buffer); - return error; -} - -unsigned lodepng_decode32_file(unsigned char** out, unsigned* w, unsigned* h, const char* filename) -{ - return lodepng_decode_file(out, w, h, filename, LCT_RGBA, 8); -} - -unsigned lodepng_decode24_file(unsigned char** out, unsigned* w, unsigned* h, const char* filename) -{ - return lodepng_decode_file(out, w, h, filename, LCT_RGB, 8); -} -#endif /*LODEPNG_COMPILE_DISK*/ - -void lodepng_decoder_settings_init(LodePNGDecoderSettings* settings) -{ - settings->color_convert = 1; -#ifdef LODEPNG_COMPILE_ANCILLARY_CHUNKS - settings->read_text_chunks = 1; - settings->remember_unknown_chunks = 0; -#endif /*LODEPNG_COMPILE_ANCILLARY_CHUNKS*/ - settings->ignore_crc = 0; - lodepng_decompress_settings_init(&settings->zlibsettings); -} - -#endif /*LODEPNG_COMPILE_DECODER*/ - -#if defined(LODEPNG_COMPILE_DECODER) || defined(LODEPNG_COMPILE_ENCODER) - -void lodepng_state_init(LodePNGState* state) -{ -#ifdef LODEPNG_COMPILE_DECODER - lodepng_decoder_settings_init(&state->decoder); -#endif /*LODEPNG_COMPILE_DECODER*/ -#ifdef LODEPNG_COMPILE_ENCODER - lodepng_encoder_settings_init(&state->encoder); -#endif /*LODEPNG_COMPILE_ENCODER*/ - lodepng_color_mode_init(&state->info_raw); - lodepng_info_init(&state->info_png); - state->error = 1; -} - -void lodepng_state_cleanup(LodePNGState* state) -{ - lodepng_color_mode_cleanup(&state->info_raw); - lodepng_info_cleanup(&state->info_png); -} - -void lodepng_state_copy(LodePNGState* dest, const LodePNGState* source) -{ - lodepng_state_cleanup(dest); - *dest = *source; - lodepng_color_mode_init(&dest->info_raw); - lodepng_info_init(&dest->info_png); - dest->error = lodepng_color_mode_copy(&dest->info_raw, &source->info_raw); if(dest->error) return; - dest->error = lodepng_info_copy(&dest->info_png, &source->info_png); if(dest->error) return; -} - -#endif /* defined(LODEPNG_COMPILE_DECODER) || defined(LODEPNG_COMPILE_ENCODER) */ - -#ifdef LODEPNG_COMPILE_ENCODER - -/* ////////////////////////////////////////////////////////////////////////// */ -/* / PNG Encoder / */ -/* ////////////////////////////////////////////////////////////////////////// */ - -/*chunkName must be string of 4 characters*/ -static unsigned addChunk(ucvector* out, const char* chunkName, const unsigned char* data, size_t length) -{ - CERROR_TRY_RETURN(lodepng_chunk_create(&out->data, &out->size, (unsigned)length, chunkName, data)); - out->allocsize = out->size; /*fix the allocsize again*/ - return 0; -} - -static void writeSignature(ucvector* out) -{ - /*8 bytes PNG signature, aka the magic bytes*/ - ucvector_push_back(out, 137); - ucvector_push_back(out, 80); - ucvector_push_back(out, 78); - ucvector_push_back(out, 71); - ucvector_push_back(out, 13); - ucvector_push_back(out, 10); - ucvector_push_back(out, 26); - ucvector_push_back(out, 10); -} - -static unsigned addChunk_IHDR(ucvector* out, unsigned w, unsigned h, - LodePNGColorType colortype, unsigned bitdepth, unsigned interlace_method) -{ - unsigned error = 0; - ucvector header; - ucvector_init(&header); - - lodepng_add32bitInt(&header, w); /*width*/ - lodepng_add32bitInt(&header, h); /*height*/ - ucvector_push_back(&header, (unsigned char)bitdepth); /*bit depth*/ - ucvector_push_back(&header, (unsigned char)colortype); /*color type*/ - ucvector_push_back(&header, 0); /*compression method*/ - ucvector_push_back(&header, 0); /*filter method*/ - ucvector_push_back(&header, interlace_method); /*interlace method*/ - - error = addChunk(out, "IHDR", header.data, header.size); - ucvector_cleanup(&header); - - return error; -} - -static unsigned addChunk_PLTE(ucvector* out, const LodePNGColorMode* info) -{ - unsigned error = 0; - size_t i; - ucvector PLTE; - ucvector_init(&PLTE); - for(i = 0; i < info->palettesize * 4; i++) - { - /*add all channels except alpha channel*/ - if(i % 4 != 3) ucvector_push_back(&PLTE, info->palette[i]); - } - error = addChunk(out, "PLTE", PLTE.data, PLTE.size); - ucvector_cleanup(&PLTE); - - return error; -} - -static unsigned addChunk_tRNS(ucvector* out, const LodePNGColorMode* info) -{ - unsigned error = 0; - size_t i; - ucvector tRNS; - ucvector_init(&tRNS); - if(info->colortype == LCT_PALETTE) - { - size_t amount = info->palettesize; - /*the tail of palette values that all have 255 as alpha, does not have to be encoded*/ - for(i = info->palettesize; i > 0; i--) - { - if(info->palette[4 * (i - 1) + 3] == 255) amount--; - else break; - } - /*add only alpha channel*/ - for(i = 0; i < amount; i++) ucvector_push_back(&tRNS, info->palette[4 * i + 3]); - } - else if(info->colortype == LCT_GREY) - { - if(info->key_defined) - { - ucvector_push_back(&tRNS, (unsigned char)(info->key_r / 256)); - ucvector_push_back(&tRNS, (unsigned char)(info->key_r % 256)); - } - } - else if(info->colortype == LCT_RGB) - { - if(info->key_defined) - { - ucvector_push_back(&tRNS, (unsigned char)(info->key_r / 256)); - ucvector_push_back(&tRNS, (unsigned char)(info->key_r % 256)); - ucvector_push_back(&tRNS, (unsigned char)(info->key_g / 256)); - ucvector_push_back(&tRNS, (unsigned char)(info->key_g % 256)); - ucvector_push_back(&tRNS, (unsigned char)(info->key_b / 256)); - ucvector_push_back(&tRNS, (unsigned char)(info->key_b % 256)); - } - } - - error = addChunk(out, "tRNS", tRNS.data, tRNS.size); - ucvector_cleanup(&tRNS); - - return error; -} - -static unsigned addChunk_IDAT(ucvector* out, const unsigned char* data, size_t datasize, - LodePNGCompressSettings* zlibsettings) -{ - ucvector zlibdata; - unsigned error = 0; - - /*compress with the Zlib compressor*/ - ucvector_init(&zlibdata); - error = lodepng_zlib_compress(&zlibdata.data, &zlibdata.size, data, datasize, zlibsettings); - if(!error) error = addChunk(out, "IDAT", zlibdata.data, zlibdata.size); - ucvector_cleanup(&zlibdata); - - return error; -} - -static unsigned addChunk_IEND(ucvector* out) -{ - unsigned error = 0; - error = addChunk(out, "IEND", 0, 0); - return error; -} - -#ifdef LODEPNG_COMPILE_ANCILLARY_CHUNKS - -static unsigned addChunk_tEXt(ucvector* out, const char* keyword, const char* textstring) -{ - unsigned error = 0; - size_t i; - ucvector text; - ucvector_init(&text); - for(i = 0; keyword[i] != 0; i++) ucvector_push_back(&text, (unsigned char)keyword[i]); - ucvector_push_back(&text, 0); - for(i = 0; textstring[i] != 0; i++) ucvector_push_back(&text, (unsigned char)textstring[i]); - error = addChunk(out, "tEXt", text.data, text.size); - ucvector_cleanup(&text); - - return error; -} - -static unsigned addChunk_zTXt(ucvector* out, const char* keyword, const char* textstring, - LodePNGCompressSettings* zlibsettings) -{ - unsigned error = 0; - ucvector data, compressed; - size_t i, textsize = strlen(textstring); - - ucvector_init(&data); - ucvector_init(&compressed); - for(i = 0; keyword[i] != 0; i++) ucvector_push_back(&data, (unsigned char)keyword[i]); - ucvector_push_back(&data, 0); /*0 termination char*/ - ucvector_push_back(&data, 0); /*compression method: 0*/ - - error = lodepng_zlib_compress(&compressed.data, &compressed.size, - (unsigned char*)textstring, textsize, zlibsettings); - if(!error) - { - for(i = 0; i < compressed.size; i++) ucvector_push_back(&data, compressed.data[i]); - error = addChunk(out, "zTXt", data.data, data.size); - } - - ucvector_cleanup(&compressed); - ucvector_cleanup(&data); - return error; -} - -static unsigned addChunk_iTXt(ucvector* out, unsigned compressed, const char* keyword, const char* langtag, - const char* transkey, const char* textstring, LodePNGCompressSettings* zlibsettings) -{ - unsigned error = 0; - ucvector data; - size_t i, textsize = strlen(textstring); - - ucvector_init(&data); - - for(i = 0; keyword[i] != 0; i++) ucvector_push_back(&data, (unsigned char)keyword[i]); - ucvector_push_back(&data, 0); /*null termination char*/ - ucvector_push_back(&data, compressed ? 1 : 0); /*compression flag*/ - ucvector_push_back(&data, 0); /*compression method*/ - for(i = 0; langtag[i] != 0; i++) ucvector_push_back(&data, (unsigned char)langtag[i]); - ucvector_push_back(&data, 0); /*null termination char*/ - for(i = 0; transkey[i] != 0; i++) ucvector_push_back(&data, (unsigned char)transkey[i]); - ucvector_push_back(&data, 0); /*null termination char*/ - - if(compressed) - { - ucvector compressed_data; - ucvector_init(&compressed_data); - error = lodepng_zlib_compress(&compressed_data.data, &compressed_data.size, - (unsigned char*)textstring, textsize, zlibsettings); - if(!error) - { - for(i = 0; i < compressed_data.size; i++) ucvector_push_back(&data, compressed_data.data[i]); - } - ucvector_cleanup(&compressed_data); - } - else /*not compressed*/ - { - for(i = 0; textstring[i] != 0; i++) ucvector_push_back(&data, (unsigned char)textstring[i]); - } - - if(!error) error = addChunk(out, "iTXt", data.data, data.size); - ucvector_cleanup(&data); - return error; -} - -static unsigned addChunk_bKGD(ucvector* out, const LodePNGInfo* info) -{ - unsigned error = 0; - ucvector bKGD; - ucvector_init(&bKGD); - if(info->color.colortype == LCT_GREY || info->color.colortype == LCT_GREY_ALPHA) - { - ucvector_push_back(&bKGD, (unsigned char)(info->background_r / 256)); - ucvector_push_back(&bKGD, (unsigned char)(info->background_r % 256)); - } - else if(info->color.colortype == LCT_RGB || info->color.colortype == LCT_RGBA) - { - ucvector_push_back(&bKGD, (unsigned char)(info->background_r / 256)); - ucvector_push_back(&bKGD, (unsigned char)(info->background_r % 256)); - ucvector_push_back(&bKGD, (unsigned char)(info->background_g / 256)); - ucvector_push_back(&bKGD, (unsigned char)(info->background_g % 256)); - ucvector_push_back(&bKGD, (unsigned char)(info->background_b / 256)); - ucvector_push_back(&bKGD, (unsigned char)(info->background_b % 256)); - } - else if(info->color.colortype == LCT_PALETTE) - { - ucvector_push_back(&bKGD, (unsigned char)(info->background_r % 256)); /*palette index*/ - } - - error = addChunk(out, "bKGD", bKGD.data, bKGD.size); - ucvector_cleanup(&bKGD); - - return error; -} - -static unsigned addChunk_tIME(ucvector* out, const LodePNGTime* time) -{ - unsigned error = 0; - unsigned char* data = (unsigned char*)mymalloc(7); - if(!data) return 83; /*alloc fail*/ - data[0] = (unsigned char)(time->year / 256); - data[1] = (unsigned char)(time->year % 256); - data[2] = time->month; - data[3] = time->day; - data[4] = time->hour; - data[5] = time->minute; - data[6] = time->second; - error = addChunk(out, "tIME", data, 7); - myfree(data); - return error; -} - -static unsigned addChunk_pHYs(ucvector* out, const LodePNGInfo* info) -{ - unsigned error = 0; - ucvector data; - ucvector_init(&data); - - lodepng_add32bitInt(&data, info->phys_x); - lodepng_add32bitInt(&data, info->phys_y); - ucvector_push_back(&data, info->phys_unit); - - error = addChunk(out, "pHYs", data.data, data.size); - ucvector_cleanup(&data); - - return error; -} - -#endif /*LODEPNG_COMPILE_ANCILLARY_CHUNKS*/ - -static void filterScanline(unsigned char* out, const unsigned char* scanline, const unsigned char* prevline, - size_t length, size_t bytewidth, unsigned char filterType) -{ - size_t i; - switch(filterType) - { - case 0: /*None*/ - for(i = 0; i < length; i++) out[i] = scanline[i]; - break; - case 1: /*Sub*/ - if(prevline) - { - for(i = 0; i < bytewidth; i++) out[i] = scanline[i]; - for(i = bytewidth; i < length; i++) out[i] = scanline[i] - scanline[i - bytewidth]; - } - else - { - for(i = 0; i < bytewidth; i++) out[i] = scanline[i]; - for(i = bytewidth; i < length; i++) out[i] = scanline[i] - scanline[i - bytewidth]; - } - break; - case 2: /*Up*/ - if(prevline) - { - for(i = 0; i < length; i++) out[i] = scanline[i] - prevline[i]; - } - else - { - for(i = 0; i < length; i++) out[i] = scanline[i]; - } - break; - case 3: /*Average*/ - if(prevline) - { - for(i = 0; i < bytewidth; i++) out[i] = scanline[i] - prevline[i] / 2; - for(i = bytewidth; i < length; i++) out[i] = scanline[i] - ((scanline[i - bytewidth] + prevline[i]) / 2); - } - else - { - for(i = 0; i < bytewidth; i++) out[i] = scanline[i]; - for(i = bytewidth; i < length; i++) out[i] = scanline[i] - scanline[i - bytewidth] / 2; - } - break; - case 4: /*Paeth*/ - if(prevline) - { - /*paethPredictor(0, prevline[i], 0) is always prevline[i]*/ - for(i = 0; i < bytewidth; i++) out[i] = (scanline[i] - prevline[i]); - for(i = bytewidth; i < length; i++) - { - out[i] = (scanline[i] - paethPredictor(scanline[i - bytewidth], prevline[i], prevline[i - bytewidth])); - } - } - else - { - for(i = 0; i < bytewidth; i++) out[i] = scanline[i]; - /*paethPredictor(scanline[i - bytewidth], 0, 0) is always scanline[i - bytewidth]*/ - for(i = bytewidth; i < length; i++) out[i] = (scanline[i] - scanline[i - bytewidth]); - } - break; - default: return; /*unexisting filter type given*/ - } -} - -static unsigned filter(unsigned char* out, const unsigned char* in, unsigned w, unsigned h, - const LodePNGColorMode* info, const LodePNGEncoderSettings* settings) -{ - /* - For PNG filter method 0 - out must be a buffer with as size: h + (w * h * bpp + 7) / 8, because there are - the scanlines with 1 extra byte per scanline - */ - - unsigned bpp = lodepng_get_bpp(info); - /*the width of a scanline in bytes, not including the filter type*/ - size_t linebytes = (w * bpp + 7) / 8; - /*bytewidth is used for filtering, is 1 when bpp < 8, number of bytes per pixel otherwise*/ - size_t bytewidth = (bpp + 7) / 8; - const unsigned char* prevline = 0; - unsigned x, y; - unsigned error = 0; - /* - There is a heuristic called the minimum sum of absolute differences heuristic, suggested by the PNG standard: - * If the image type is Palette, or the bit depth is smaller than 8, then do not filter the image (i.e. - use fixed filtering, with the filter None). - * (The other case) If the image type is Grayscale or RGB (with or without Alpha), and the bit depth is - not smaller than 8, then use adaptive filtering heuristic as follows: independently for each row, apply - all five filters and select the filter that produces the smallest sum of absolute values per row. - This heuristic is used if filter strategy is LFS_HEURISTIC. Parts of it are used for filter strategies - LFS_MINSUM and LFS_ZERO. - */ - int heuristic_zero = info->colortype == LCT_PALETTE || info->bitdepth < 8; - - if(bpp == 0) return 31; /*error: invalid color type*/ - - if((!heuristic_zero && settings->filter_strategy == LFS_HEURISTIC)|| - settings->filter_strategy == LFS_MINSUM) - { - /*adaptive filtering*/ - size_t sum[5]; - ucvector attempt[5]; /*five filtering attempts, one for each filter type*/ - size_t smallest = 0; - unsigned type, bestType = 0; - - for(type = 0; type < 5; type++) ucvector_init(&attempt[type]); - - for(type = 0; type < 5; type++) - { - if(!ucvector_resize(&attempt[type], linebytes)) ERROR_BREAK(83 /*alloc fail*/); - } - - if(!error) - { - for(y = 0; y < h; y++) - { - /*try the 5 filter types*/ - for(type = 0; type < 5; type++) - { - filterScanline(attempt[type].data, &in[y * linebytes], prevline, linebytes, bytewidth, type); - - /*calculate the sum of the result*/ - sum[type] = 0; - /*note that not all pixels are checked to speed this up while still having probably the best choice*/ - for(x = 0; x < attempt[type].size; x+=3) - { - /*For differences, each byte should be treated as signed, values above 127 are negative - (converted to signed char). Filtertype 0 isn't a difference though, so use unsigned there. - This means filtertype 0 is almost never chosen, but that is justified.*/ - if(type == 0) sum[type] += (unsigned char)(attempt[type].data[x]); - else - { - signed char s = (signed char)(attempt[type].data[x]); - sum[type] += s < 0 ? -s : s; - } - } - - /*check if this is smallest sum (or if type == 0 it's the first case so always store the values)*/ - if(type == 0 || sum[type] < smallest) - { - bestType = type; - smallest = sum[type]; - } - } - - prevline = &in[y * linebytes]; - - /*now fill the out values*/ - out[y * (linebytes + 1)] = bestType; /*the first byte of a scanline will be the filter type*/ - for(x = 0; x < linebytes; x++) out[y * (linebytes + 1) + 1 + x] = attempt[bestType].data[x]; - } - } - - for(type = 0; type < 5; type++) ucvector_cleanup(&attempt[type]); - } - else if((heuristic_zero && settings->filter_strategy == LFS_HEURISTIC)|| - settings->filter_strategy == LFS_ZERO) - { - for(y = 0; y < h; y++) - { - size_t outindex = (1 + linebytes) * y; /*the extra filterbyte added to each row*/ - size_t inindex = linebytes * y; - const unsigned TYPE = 0; - out[outindex] = TYPE; /*filter type byte*/ - filterScanline(&out[outindex + 1], &in[inindex], prevline, linebytes, bytewidth, TYPE); - prevline = &in[inindex]; - } - } - else if(settings->filter_strategy == LFS_PREDEFINED) - { - for(y = 0; y < h; y++) - { - size_t outindex = (1 + linebytes) * y; /*the extra filterbyte added to each row*/ - size_t inindex = linebytes * y; - unsigned type = settings->predefined_filters[y]; - out[outindex] = type; /*filter type byte*/ - filterScanline(&out[outindex + 1], &in[inindex], prevline, linebytes, bytewidth, type); - prevline = &in[inindex]; - } - } - else /*LFS_BRUTE_FORCE*/ - { - /*brute force filter chooser. - deflate the scanline after every filter attempt to see which one deflates best. - This is very slow and gives only slightly smaller, sometimes even larger, result*/ - size_t size[5]; - ucvector attempt[5]; /*five filtering attempts, one for each filter type*/ - size_t smallest = 0; - unsigned type = 0, bestType = 0; - unsigned char* dummy; - LodePNGCompressSettings zlibsettings = settings->zlibsettings; - /*use fixed tree on the attempts so that the tree is not adapted to the filtertype on purpose, - to simulate the true case where the tree is the same for the whole image. Sometimes it gives - better result with dynamic tree anyway. Using the fixed tree sometimes gives worse, but in rare - cases better compression. It does make this a bit less slow, so it's worth doing this.*/ - zlibsettings.btype = 1; - /*a custom encoder likely doesn't read the btype setting and is optimized for complete PNG - images only, so disable it*/ - zlibsettings.custom_encoder = 0; - for(type = 0; type < 5; type++) - { - ucvector_init(&attempt[type]); - ucvector_resize(&attempt[type], linebytes); /*todo: give error if resize failed*/ - } - for(y = 0; y < h; y++) /*try the 5 filter types*/ - { - for(type = 0; type < 5; type++) - { - unsigned testsize = attempt[type].size; - /*if(testsize > 8) testsize /= 8;*/ /*it already works good enough by testing a part of the row*/ - - filterScanline(attempt[type].data, &in[y * linebytes], prevline, linebytes, bytewidth, type); - size[type] = 0; - dummy = 0; - lodepng_zlib_compress(&dummy, &size[type], attempt[type].data, testsize, &zlibsettings); - myfree(dummy); - /*check if this is smallest size (or if type == 0 it's the first case so always store the values)*/ - if(type == 0 || size[type] < smallest) - { - bestType = type; - smallest = size[type]; - } - } - prevline = &in[y * linebytes]; - out[y * (linebytes + 1)] = bestType; /*the first byte of a scanline will be the filter type*/ - for(x = 0; x < linebytes; x++) out[y * (linebytes + 1) + 1 + x] = attempt[bestType].data[x]; - } - for(type = 0; type < 5; type++) ucvector_cleanup(&attempt[type]); - } - - return error; -} - -static void addPaddingBits(unsigned char* out, const unsigned char* in, - size_t olinebits, size_t ilinebits, unsigned h) -{ - /*The opposite of the removePaddingBits function - olinebits must be >= ilinebits*/ - unsigned y; - size_t diff = olinebits - ilinebits; - size_t obp = 0, ibp = 0; /*bit pointers*/ - for(y = 0; y < h; y++) - { - size_t x; - for(x = 0; x < ilinebits; x++) - { - unsigned char bit = readBitFromReversedStream(&ibp, in); - setBitOfReversedStream(&obp, out, bit); - } - /*obp += diff; --> no, fill in some value in the padding bits too, to avoid - "Use of uninitialised value of size ###" warning from valgrind*/ - for(x = 0; x < diff; x++) setBitOfReversedStream(&obp, out, 0); - } -} - -static void Adam7_interlace(unsigned char* out, const unsigned char* in, unsigned w, unsigned h, unsigned bpp) -{ - /*Note: this function works on image buffers WITHOUT padding bits at end of scanlines with non-multiple-of-8 - bit amounts, only between reduced images is padding*/ - unsigned passw[7], passh[7]; - size_t filter_passstart[8], padded_passstart[8], passstart[8]; - unsigned i; - - Adam7_getpassvalues(passw, passh, filter_passstart, padded_passstart, passstart, w, h, bpp); - - if(bpp >= 8) - { - for(i = 0; i < 7; i++) - { - unsigned x, y, b; - size_t bytewidth = bpp / 8; - for(y = 0; y < passh[i]; y++) - for(x = 0; x < passw[i]; x++) - { - size_t pixelinstart = ((ADAM7_IY[i] + y * ADAM7_DY[i]) * w + ADAM7_IX[i] + x * ADAM7_DX[i]) * bytewidth; - size_t pixeloutstart = passstart[i] + (y * passw[i] + x) * bytewidth; - for(b = 0; b < bytewidth; b++) - { - out[pixeloutstart + b] = in[pixelinstart + b]; - } - } - } - } - else /*bpp < 8: Adam7 with pixels < 8 bit is a bit trickier: with bit pointers*/ - { - for(i = 0; i < 7; i++) - { - unsigned x, y, b; - unsigned ilinebits = bpp * passw[i]; - unsigned olinebits = bpp * w; - size_t obp, ibp; /*bit pointers (for out and in buffer)*/ - for(y = 0; y < passh[i]; y++) - for(x = 0; x < passw[i]; x++) - { - ibp = (ADAM7_IY[i] + y * ADAM7_DY[i]) * olinebits + (ADAM7_IX[i] + x * ADAM7_DX[i]) * bpp; - obp = (8 * passstart[i]) + (y * ilinebits + x * bpp); - for(b = 0; b < bpp; b++) - { - unsigned char bit = readBitFromReversedStream(&ibp, in); - setBitOfReversedStream(&obp, out, bit); - } - } - } - } -} - -/*out must be buffer big enough to contain uncompressed IDAT chunk data, and in must contain the full image. -return value is error**/ -static unsigned preProcessScanlines(unsigned char** out, size_t* outsize, const unsigned char* in, - unsigned w, unsigned h, - const LodePNGInfo* info_png, const LodePNGEncoderSettings* settings) -{ - /* - This function converts the pure 2D image with the PNG's colortype, into filtered-padded-interlaced data. Steps: - *) if no Adam7: 1) add padding bits (= posible extra bits per scanline if bpp < 8) 2) filter - *) if adam7: 1) Adam7_interlace 2) 7x add padding bits 3) 7x filter - */ - unsigned bpp = lodepng_get_bpp(&info_png->color); - unsigned error = 0; - - if(info_png->interlace_method == 0) - { - *outsize = h + (h * ((w * bpp + 7) / 8)); /*image size plus an extra byte per scanline + possible padding bits*/ - *out = (unsigned char*)mymalloc(*outsize); - if(!(*out) && (*outsize)) error = 83; /*alloc fail*/ - - if(!error) - { - /*non multiple of 8 bits per scanline, padding bits needed per scanline*/ - if(bpp < 8 && w * bpp != ((w * bpp + 7) / 8) * 8) - { - ucvector padded; - ucvector_init(&padded); - if(!ucvector_resize(&padded, h * ((w * bpp + 7) / 8))) error = 83; /*alloc fail*/ - if(!error) - { - addPaddingBits(padded.data, in, ((w * bpp + 7) / 8) * 8, w * bpp, h); - error = filter(*out, padded.data, w, h, &info_png->color, settings); - } - ucvector_cleanup(&padded); - } - else - { - /*we can immediatly filter into the out buffer, no other steps needed*/ - error = filter(*out, in, w, h, &info_png->color, settings); - } - } - } - else /*interlace_method is 1 (Adam7)*/ - { - unsigned char* adam7 = (unsigned char*)mymalloc((h * w * bpp + 7) / 8); - if(!adam7 && ((h * w * bpp + 7) / 8)) error = 83; /*alloc fail*/ - - while(!error) /*not a real while loop, used to break out to cleanup to avoid a goto*/ - { - unsigned passw[7], passh[7]; - size_t filter_passstart[8], padded_passstart[8], passstart[8]; - unsigned i; - - Adam7_getpassvalues(passw, passh, filter_passstart, padded_passstart, passstart, w, h, bpp); - - *outsize = filter_passstart[7]; /*image size plus an extra byte per scanline + possible padding bits*/ - *out = (unsigned char*)mymalloc(*outsize); - if(!(*out) && (*outsize)) ERROR_BREAK(83 /*alloc fail*/); - - Adam7_interlace(adam7, in, w, h, bpp); - - for(i = 0; i < 7; i++) - { - if(bpp < 8) - { - ucvector padded; - ucvector_init(&padded); - if(!ucvector_resize(&padded, h * ((w * bpp + 7) / 8))) error = 83; /*alloc fail*/ - if(!error) - { - addPaddingBits(&padded.data[padded_passstart[i]], &adam7[passstart[i]], - ((passw[i] * bpp + 7) / 8) * 8, passw[i] * bpp, passh[i]); - error = filter(&(*out)[filter_passstart[i]], &padded.data[padded_passstart[i]], - passw[i], passh[i], &info_png->color, settings); - } - - ucvector_cleanup(&padded); - } - else - { - error = filter(&(*out)[filter_passstart[i]], &adam7[padded_passstart[i]], - passw[i], passh[i], &info_png->color, settings); - } - } - - break; - } - - myfree(adam7); - } - - return error; -} - -/* -palette must have 4 * palettesize bytes allocated, and given in format RGBARGBARGBARGBA... -returns 0 if the palette is opaque, -returns 1 if the palette has a single color with alpha 0 ==> color key -returns 2 if the palette is semi-translucent. -*/ -static unsigned getPaletteTranslucency(const unsigned char* palette, size_t palettesize) -{ - size_t i, key = 0; - unsigned r, g, b; /*the value of the color with alpha 0, so long as color keying is possible*/ - for(i = 0; i < palettesize; i++) - { - if(!key && palette[4 * i + 3] == 0) - { - r = palette[4 * i + 0]; g = palette[4 * i + 1]; b = palette[4 * i + 2]; - key = 1; - i = (size_t)(-1); /*restart from beginning, to detect earlier opaque colors with key's value*/ - } - else if(palette[4 * i + 3] != 255) return 2; - /*when key, no opaque RGB may have key's RGB*/ - else if(key && r == palette[i * 4 + 0] && g == palette[i * 4 + 1] && b == palette[i * 4 + 2]) return 2; - } - return key; -} - -#ifdef LODEPNG_COMPILE_ANCILLARY_CHUNKS -static unsigned addUnknownChunks(ucvector* out, unsigned char* data, size_t datasize) -{ - unsigned char* inchunk = data; - while((size_t)(inchunk - data) < datasize) - { - CERROR_TRY_RETURN(lodepng_chunk_append(&out->data, &out->size, inchunk)); - out->allocsize = out->size; /*fix the allocsize again*/ - inchunk = lodepng_chunk_next(inchunk); - } - return 0; -} -#endif /*LODEPNG_COMPILE_ANCILLARY_CHUNKS*/ - -unsigned lodepng_encode(unsigned char** out, size_t* outsize, - const unsigned char* image, unsigned w, unsigned h, - LodePNGState* state) -{ - LodePNGInfo info; - ucvector outv; - unsigned char* data = 0; /*uncompressed version of the IDAT chunk data*/ - size_t datasize = 0; - - /*provide some proper output values if error will happen*/ - *out = 0; - *outsize = 0; - state->error = 0; - - lodepng_info_init(&info); - lodepng_info_copy(&info, &state->info_png); - - if((info.color.colortype == LCT_PALETTE || state->encoder.force_palette) - && (info.color.palettesize == 0 || info.color.palettesize > 256)) - { - state->error = 68; /*invalid palette size, it is only allowed to be 1-256*/ - return state->error; - } - - if(state->encoder.auto_convert != LAC_NO) - { - state->error = doAutoChooseColor(&info.color, image, w, h, &state->info_raw, - state->encoder.auto_convert); - } - if(state->error) return state->error; - - if(state->encoder.zlibsettings.windowsize > 32768) - { - CERROR_RETURN_ERROR(state->error, 60); /*error: windowsize larger than allowed*/ - } - if(state->encoder.zlibsettings.btype > 2) - { - CERROR_RETURN_ERROR(state->error, 61); /*error: unexisting btype*/ - } - if(state->info_png.interlace_method > 1) - { - CERROR_RETURN_ERROR(state->error, 71); /*error: unexisting interlace mode*/ - } - /*error: unexisting color type given*/ - if((state->error = checkColorValidity(info.color.colortype, info.color.bitdepth))) return state->error; - /*error: unexisting color type given*/ - if((state->error = checkColorValidity(state->info_raw.colortype, state->info_raw.bitdepth))) return state->error; - - if(!lodepng_color_mode_equal(&state->info_raw, &info.color)) - { - unsigned char* converted; - size_t size = (w * h * lodepng_get_bpp(&info.color) + 7) / 8; - - converted = (unsigned char*)mymalloc(size); - if(!converted && size) state->error = 83; /*alloc fail*/ - if(!state->error) - { - state->error = lodepng_convert(converted, image, &info.color, &state->info_raw, w, h); - } - if(!state->error) preProcessScanlines(&data, &datasize, converted, w, h, &info, &state->encoder); - myfree(converted); - } - else preProcessScanlines(&data, &datasize, image, w, h, &info, &state->encoder); - - ucvector_init(&outv); - while(!state->error) /*while only executed once, to break on error*/ - { -#ifdef LODEPNG_COMPILE_ANCILLARY_CHUNKS - size_t i; -#endif /*LODEPNG_COMPILE_ANCILLARY_CHUNKS*/ - /*write signature and chunks*/ - writeSignature(&outv); - /*IHDR*/ - addChunk_IHDR(&outv, w, h, info.color.colortype, info.color.bitdepth, info.interlace_method); -#ifdef LODEPNG_COMPILE_ANCILLARY_CHUNKS - /*unknown chunks between IHDR and PLTE*/ - if(info.unknown_chunks_data[0]) - { - state->error = addUnknownChunks(&outv, info.unknown_chunks_data[0], info.unknown_chunks_size[0]); - if(state->error) break; - } -#endif /*LODEPNG_COMPILE_ANCILLARY_CHUNKS*/ - /*PLTE*/ - if(info.color.colortype == LCT_PALETTE) - { - addChunk_PLTE(&outv, &info.color); - } - if(state->encoder.force_palette && (info.color.colortype == LCT_RGB || info.color.colortype == LCT_RGBA)) - { - addChunk_PLTE(&outv, &info.color); - } - /*tRNS*/ - if(info.color.colortype == LCT_PALETTE && getPaletteTranslucency(info.color.palette, info.color.palettesize) != 0) - { - addChunk_tRNS(&outv, &info.color); - } - if((info.color.colortype == LCT_GREY || info.color.colortype == LCT_RGB) && info.color.key_defined) - { - addChunk_tRNS(&outv, &info.color); - } -#ifdef LODEPNG_COMPILE_ANCILLARY_CHUNKS - /*bKGD (must come between PLTE and the IDAt chunks*/ - if(info.background_defined) addChunk_bKGD(&outv, &info); - /*pHYs (must come before the IDAT chunks)*/ - if(info.phys_defined) addChunk_pHYs(&outv, &info); - - /*unknown chunks between PLTE and IDAT*/ - if(info.unknown_chunks_data[1]) - { - state->error = addUnknownChunks(&outv, info.unknown_chunks_data[1], info.unknown_chunks_size[1]); - if(state->error) break; - } -#endif /*LODEPNG_COMPILE_ANCILLARY_CHUNKS*/ - /*IDAT (multiple IDAT chunks must be consecutive)*/ - state->error = addChunk_IDAT(&outv, data, datasize, &state->encoder.zlibsettings); - if(state->error) break; -#ifdef LODEPNG_COMPILE_ANCILLARY_CHUNKS - /*tIME*/ - if(info.time_defined) addChunk_tIME(&outv, &info.time); - /*tEXt and/or zTXt*/ - for(i = 0; i < info.text_num; i++) - { - if(strlen(info.text_keys[i]) > 79) - { - state->error = 66; /*text chunk too large*/ - break; - } - if(strlen(info.text_keys[i]) < 1) - { - state->error = 67; /*text chunk too small*/ - break; - } - if(state->encoder.text_compression) - addChunk_zTXt(&outv, info.text_keys[i], info.text_strings[i], &state->encoder.zlibsettings); - else - addChunk_tEXt(&outv, info.text_keys[i], info.text_strings[i]); - } - /*LodePNG version id in text chunk*/ - if(state->encoder.add_id) - { - unsigned alread_added_id_text = 0; - for(i = 0; i < info.text_num; i++) - { - if(!strcmp(info.text_keys[i], "LodePNG")) - { - alread_added_id_text = 1; - break; - } - } - if(alread_added_id_text == 0) - addChunk_tEXt(&outv, "LodePNG", VERSION_STRING); /*it's shorter as tEXt than as zTXt chunk*/ - } - /*iTXt*/ - for(i = 0; i < info.itext_num; i++) - { - if(strlen(info.itext_keys[i]) > 79) - { - state->error = 66; /*text chunk too large*/ - break; - } - if(strlen(info.itext_keys[i]) < 1) - { - state->error = 67; /*text chunk too small*/ - break; - } - addChunk_iTXt(&outv, state->encoder.text_compression, - info.itext_keys[i], info.itext_langtags[i], info.itext_transkeys[i], info.itext_strings[i], - &state->encoder.zlibsettings); - } - - /*unknown chunks between IDAT and IEND*/ - if(info.unknown_chunks_data[2]) - { - state->error = addUnknownChunks(&outv, info.unknown_chunks_data[2], info.unknown_chunks_size[2]); - if(state->error) break; - } -#endif /*LODEPNG_COMPILE_ANCILLARY_CHUNKS*/ - /*IEND*/ - addChunk_IEND(&outv); - - break; /*this isn't really a while loop; no error happened so break out now!*/ - } - - lodepng_info_cleanup(&info); - myfree(data); - /*instead of cleaning the vector up, give it to the output*/ - *out = outv.data; - *outsize = outv.size; - - return state->error; -} - -unsigned lodepng_encode_memory(unsigned char** out, size_t* outsize, const unsigned char* image, - unsigned w, unsigned h, LodePNGColorType colortype, unsigned bitdepth) -{ - unsigned error; - LodePNGState state; - lodepng_state_init(&state); - state.info_raw.colortype = colortype; - state.info_raw.bitdepth = bitdepth; - state.info_png.color.colortype = colortype; - state.info_png.color.bitdepth = bitdepth; - lodepng_encode(out, outsize, image, w, h, &state); - error = state.error; - lodepng_state_cleanup(&state); - return error; -} - -unsigned lodepng_encode32(unsigned char** out, size_t* outsize, const unsigned char* image, unsigned w, unsigned h) -{ - return lodepng_encode_memory(out, outsize, image, w, h, LCT_RGBA, 8); -} - -unsigned lodepng_encode24(unsigned char** out, size_t* outsize, const unsigned char* image, unsigned w, unsigned h) -{ - return lodepng_encode_memory(out, outsize, image, w, h, LCT_RGB, 8); -} - -#ifdef LODEPNG_COMPILE_DISK -unsigned lodepng_encode_file(const char* filename, const unsigned char* image, unsigned w, unsigned h, - LodePNGColorType colortype, unsigned bitdepth) -{ - unsigned char* buffer; - size_t buffersize; - unsigned error = lodepng_encode_memory(&buffer, &buffersize, image, w, h, colortype, bitdepth); - if(!error) error = lodepng_save_file(buffer, buffersize, filename); - myfree(buffer); - return error; -} - -unsigned lodepng_encode32_file(const char* filename, const unsigned char* image, unsigned w, unsigned h) -{ - return lodepng_encode_file(filename, image, w, h, LCT_RGBA, 8); -} - -unsigned lodepng_encode24_file(const char* filename, const unsigned char* image, unsigned w, unsigned h) -{ - return lodepng_encode_file(filename, image, w, h, LCT_RGB, 8); -} -#endif /*LODEPNG_COMPILE_DISK*/ - -void lodepng_encoder_settings_init(LodePNGEncoderSettings* settings) -{ - lodepng_compress_settings_init(&settings->zlibsettings); - settings->filter_strategy = LFS_HEURISTIC; - settings->auto_convert = LAC_AUTO; - settings->force_palette = 0; - settings->predefined_filters = 0; -#ifdef LODEPNG_COMPILE_ANCILLARY_CHUNKS - settings->add_id = 0; - settings->text_compression = 1; -#endif /*LODEPNG_COMPILE_ANCILLARY_CHUNKS*/ -} - -#endif /*LODEPNG_COMPILE_ENCODER*/ -#endif /*LODEPNG_COMPILE_PNG*/ - -#ifdef LODEPNG_COMPILE_ERROR_TEXT -/* -This returns the description of a numerical error code in English. This is also -the documentation of all the error codes. -*/ -const char* lodepng_error_text(unsigned code) -{ - switch(code) - { - case 0: return "no error, everything went ok"; - case 1: return "nothing done yet"; /*the Encoder/Decoder has done nothing yet, error checking makes no sense yet*/ - case 10: return "end of input memory reached without huffman end code"; /*while huffman decoding*/ - case 11: return "error in code tree made it jump outside of huffman tree"; /*while huffman decoding*/ - case 13: return "problem while processing dynamic deflate block"; - case 14: return "problem while processing dynamic deflate block"; - case 15: return "problem while processing dynamic deflate block"; - case 16: return "unexisting code while processing dynamic deflate block"; - case 17: return "end of out buffer memory reached while inflating"; - case 18: return "invalid distance code while inflating"; - case 19: return "end of out buffer memory reached while inflating"; - case 20: return "invalid deflate block BTYPE encountered while decoding"; - case 21: return "NLEN is not ones complement of LEN in a deflate block"; - - /*end of out buffer memory reached while inflating: - This can happen if the inflated deflate data is longer than the amount of bytes required to fill up - all the pixels of the image, given the color depth and image dimensions. Something that doesn't - happen in a normal, well encoded, PNG image.*/ - case 22: return "end of out buffer memory reached while inflating"; - - case 23: return "end of in buffer memory reached while inflating"; - case 24: return "invalid FCHECK in zlib header"; - case 25: return "invalid compression method in zlib header"; - case 26: return "FDICT encountered in zlib header while it's not used for PNG"; - case 27: return "PNG file is smaller than a PNG header"; - /*Checks the magic file header, the first 8 bytes of the PNG file*/ - case 28: return "incorrect PNG signature, it's no PNG or corrupted"; - case 29: return "first chunk is not the header chunk"; - case 30: return "chunk length too large, chunk broken off at end of file"; - case 31: return "illegal PNG color type or bpp"; - case 32: return "illegal PNG compression method"; - case 33: return "illegal PNG filter method"; - case 34: return "illegal PNG interlace method"; - case 35: return "chunk length of a chunk is too large or the chunk too small"; - case 36: return "illegal PNG filter type encountered"; - case 37: return "illegal bit depth for this color type given"; - case 38: return "the palette is too big"; /*more than 256 colors*/ - case 39: return "more palette alpha values given in tRNS chunk than there are colors in the palette"; - case 40: return "tRNS chunk has wrong size for greyscale image"; - case 41: return "tRNS chunk has wrong size for RGB image"; - case 42: return "tRNS chunk appeared while it was not allowed for this color type"; - case 43: return "bKGD chunk has wrong size for palette image"; - case 44: return "bKGD chunk has wrong size for greyscale image"; - case 45: return "bKGD chunk has wrong size for RGB image"; - /*Is the palette too small?*/ - case 46: return "a value in indexed image is larger than the palette size (bitdepth = 8)"; - /*Is the palette too small?*/ - case 47: return "a value in indexed image is larger than the palette size (bitdepth < 8)"; - /*the input data is empty, maybe a PNG file doesn't exist or is in the wrong path*/ - case 48: return "empty input or file doesn't exist"; - case 49: return "jumped past memory while generating dynamic huffman tree"; - case 50: return "jumped past memory while generating dynamic huffman tree"; - case 51: return "jumped past memory while inflating huffman block"; - case 52: return "jumped past memory while inflating"; - case 53: return "size of zlib data too small"; - case 54: return "repeat symbol in tree while there was no value symbol yet"; - - /*jumped past tree while generating huffman tree, this could be when the - tree will have more leaves than symbols after generating it out of the - given lenghts. They call this an oversubscribed dynamic bit lengths tree in zlib.*/ - case 55: return "jumped past tree while generating huffman tree"; - - case 56: return "given output image colortype or bitdepth not supported for color conversion"; - case 57: return "invalid CRC encountered (checking CRC can be disabled)"; - case 58: return "invalid ADLER32 encountered (checking ADLER32 can be disabled)"; - case 59: return "requested color conversion not supported"; - case 60: return "invalid window size given in the settings of the encoder (must be 0-32768)"; - case 61: return "invalid BTYPE given in the settings of the encoder (only 0, 1 and 2 are allowed)"; - /*LodePNG leaves the choice of RGB to greyscale conversion formula to the user.*/ - case 62: return "conversion from color to greyscale not supported"; - case 63: return "length of a chunk too long, max allowed for PNG is 2147483647 bytes per chunk"; /*(2^31-1)*/ - /*this would result in the inability of a deflated block to ever contain an end code. It must be at least 1.*/ - case 64: return "the length of the END symbol 256 in the Huffman tree is 0"; - case 66: return "the length of a text chunk keyword given to the encoder is longer than the maximum of 79 bytes"; - case 67: return "the length of a text chunk keyword given to the encoder is smaller than the minimum of 1 byte"; - case 68: return "tried to encode a PLTE chunk with a palette that has less than 1 or more than 256 colors"; - case 69: return "unknown chunk type with 'critical' flag encountered by the decoder"; - case 71: return "unexisting interlace mode given to encoder (must be 0 or 1)"; - case 72: return "while decoding, unexisting compression method encountering in zTXt or iTXt chunk (it must be 0)"; - case 73: return "invalid tIME chunk size"; - case 74: return "invalid pHYs chunk size"; - /*length could be wrong, or data chopped off*/ - case 75: return "no null termination char found while decoding text chunk"; - case 76: return "iTXt chunk too short to contain required bytes"; - case 77: return "integer overflow in buffer size"; - case 78: return "failed to open file for reading"; /*file doesn't exist or couldn't be opened for reading*/ - case 79: return "failed to open file for writing"; - case 80: return "tried creating a tree of 0 symbols"; - case 81: return "lazy matching at pos 0 is impossible"; - case 82: return "color conversion to palette requested while a color isn't in palette"; - case 83: return "memory allocation failed"; - case 84: return "given image too small to contain all pixels to be encoded"; - case 85: return "internal color conversion bug"; - case 86: return "impossible offset in lz77 encoding (internal bug)"; - } - return "unknown error code"; -} -#endif /*LODEPNG_COMPILE_ERROR_TEXT*/ - -/* ////////////////////////////////////////////////////////////////////////// */ -/* ////////////////////////////////////////////////////////////////////////// */ -/* // C++ Wrapper // */ -/* ////////////////////////////////////////////////////////////////////////// */ -/* ////////////////////////////////////////////////////////////////////////// */ - - -#ifdef LODEPNG_COMPILE_CPP -namespace lodepng -{ - -#ifdef LODEPNG_COMPILE_DISK -void load_file(std::vector& buffer, const std::string& filename) -{ - std::ifstream file(filename.c_str(), std::ios::in|std::ios::binary|std::ios::ate); - - /*get filesize*/ - std::streamsize size = 0; - if(file.seekg(0, std::ios::end).good()) size = file.tellg(); - if(file.seekg(0, std::ios::beg).good()) size -= file.tellg(); - - /*read contents of the file into the vector*/ - buffer.resize(size_t(size)); - if(size > 0) file.read((char*)(&buffer[0]), size); -} - -/*write given buffer to the file, overwriting the file, it doesn't append to it.*/ -void save_file(const std::vector& buffer, const std::string& filename) -{ - std::ofstream file(filename.c_str(), std::ios::out|std::ios::binary); - file.write(buffer.empty() ? 0 : (char*)&buffer[0], std::streamsize(buffer.size())); -} -#endif //LODEPNG_COMPILE_DISK - -#ifdef LODEPNG_COMPILE_ZLIB -#ifdef LODEPNG_COMPILE_DECODER -unsigned decompress(std::vector& out, const unsigned char* in, size_t insize, - const LodePNGDecompressSettings& settings) -{ - unsigned char* buffer = 0; - size_t buffersize = 0; - unsigned error = lodepng_zlib_decompress(&buffer, &buffersize, in, insize, &settings); - if(buffer) - { - out.insert(out.end(), &buffer[0], &buffer[buffersize]); - myfree(buffer); - } - return error; -} - -unsigned decompress(std::vector& out, const std::vector& in, - const LodePNGDecompressSettings& settings) -{ - return decompress(out, in.empty() ? 0 : &in[0], in.size(), settings); -} -#endif //LODEPNG_COMPILE_DECODER - -#ifdef LODEPNG_COMPILE_ENCODER -unsigned compress(std::vector& out, const unsigned char* in, size_t insize, - const LodePNGCompressSettings& settings) -{ - unsigned char* buffer = 0; - size_t buffersize = 0; - unsigned error = lodepng_zlib_compress(&buffer, &buffersize, in, insize, &settings); - if(buffer) - { - out.insert(out.end(), &buffer[0], &buffer[buffersize]); - myfree(buffer); - } - return error; -} - -unsigned compress(std::vector& out, const std::vector& in, - const LodePNGCompressSettings& settings) -{ - return compress(out, in.empty() ? 0 : &in[0], in.size(), settings); -} -#endif //LODEPNG_COMPILE_ENCODER -#endif //LODEPNG_COMPILE_ZLIB - - -#ifdef LODEPNG_COMPILE_PNG - -State::State() -{ - lodepng_state_init(this); -} - -State::State(const State& other) -{ - lodepng_state_init(this); - lodepng_state_copy(this, &other); -} - -State::~State() -{ - lodepng_state_cleanup(this); -} - -State& State::operator=(const State& other) -{ - lodepng_state_copy(this, &other); - return *this; -} - -#ifdef LODEPNG_COMPILE_DECODER - -unsigned decode(std::vector& out, unsigned& w, unsigned& h, const unsigned char* in, - size_t insize, LodePNGColorType colortype, unsigned bitdepth) -{ - unsigned char* buffer; - unsigned error = lodepng_decode_memory(&buffer, &w, &h, in, insize, colortype, bitdepth); - if(buffer && !error) - { - State state; - state.info_raw.colortype = colortype; - state.info_raw.bitdepth = bitdepth; - size_t buffersize = lodepng_get_raw_size(w, h, &state.info_raw); - out.insert(out.end(), &buffer[0], &buffer[buffersize]); - myfree(buffer); - } - return error; -} - -unsigned decode(std::vector& out, unsigned& w, unsigned& h, - const std::vector& in, LodePNGColorType colortype, unsigned bitdepth) -{ - return decode(out, w, h, in.empty() ? 0 : &in[0], (unsigned)in.size(), colortype, bitdepth); -} - -unsigned decode(std::vector& out, unsigned& w, unsigned& h, - State& state, - const unsigned char* in, size_t insize) -{ - unsigned char* buffer; - unsigned error = lodepng_decode(&buffer, &w, &h, &state, in, insize); - if(buffer && !error) - { - size_t buffersize = lodepng_get_raw_size(w, h, &state.info_raw); - out.insert(out.end(), &buffer[0], &buffer[buffersize]); - myfree(buffer); - } - return error; -} - -unsigned decode(std::vector& out, unsigned& w, unsigned& h, - State& state, - const std::vector& in) -{ - return decode(out, w, h, state, in.empty() ? 0 : &in[0], in.size()); -} - -#ifdef LODEPNG_COMPILE_DISK -unsigned decode(std::vector& out, unsigned& w, unsigned& h, const std::string& filename, - LodePNGColorType colortype, unsigned bitdepth) -{ - std::vector buffer; - load_file(buffer, filename); - return decode(out, w, h, buffer, colortype, bitdepth); -} -#endif //LODEPNG_COMPILE_DECODER -#endif //LODEPNG_COMPILE_DISK - -#ifdef LODEPNG_COMPILE_ENCODER -unsigned encode(std::vector& out, const unsigned char* in, unsigned w, unsigned h, - LodePNGColorType colortype, unsigned bitdepth) -{ - unsigned char* buffer; - size_t buffersize; - unsigned error = lodepng_encode_memory(&buffer, &buffersize, in, w, h, colortype, bitdepth); - if(buffer) - { - out.insert(out.end(), &buffer[0], &buffer[buffersize]); - myfree(buffer); - } - return error; -} - -unsigned encode(std::vector& out, - const std::vector& in, unsigned w, unsigned h, - LodePNGColorType colortype, unsigned bitdepth) -{ - if(lodepng_get_raw_size_lct(w, h, colortype, bitdepth) > in.size()) return 84; - return encode(out, in.empty() ? 0 : &in[0], w, h, colortype, bitdepth); -} - -unsigned encode(std::vector& out, - const unsigned char* in, unsigned w, unsigned h, - State& state) -{ - unsigned char* buffer; - size_t buffersize; - unsigned error = lodepng_encode(&buffer, &buffersize, in, w, h, &state); - if(buffer) - { - out.insert(out.end(), &buffer[0], &buffer[buffersize]); - myfree(buffer); - } - return error; -} - -unsigned encode(std::vector& out, - const std::vector& in, unsigned w, unsigned h, - State& state) -{ - if(lodepng_get_raw_size(w, h, &state.info_raw) > in.size()) return 84; - return encode(out, in.empty() ? 0 : &in[0], w, h, state); -} - -#ifdef LODEPNG_COMPILE_DISK -unsigned encode(const std::string& filename, - const unsigned char* in, unsigned w, unsigned h, - LodePNGColorType colortype, unsigned bitdepth) -{ - std::vector buffer; - unsigned error = encode(buffer, in, w, h, colortype, bitdepth); - if(!error) save_file(buffer, filename); - return error; -} - -unsigned encode(const std::string& filename, - const std::vector& in, unsigned w, unsigned h, - LodePNGColorType colortype, unsigned bitdepth) -{ - if(lodepng_get_raw_size_lct(w, h, colortype, bitdepth) > in.size()) return 84; - return encode(filename, in.empty() ? 0 : &in[0], w, h, colortype, bitdepth); -} -#endif //LODEPNG_COMPILE_DISK -#endif //LODEPNG_COMPILE_ENCODER -#endif //LODEPNG_COMPILE_PNG -} //namespace lodepng -#endif /*LODEPNG_COMPILE_CPP*/ diff --git a/lib/lodepng.h b/lib/lodepng.h deleted file mode 100644 index 50d5303..0000000 --- a/lib/lodepng.h +++ /dev/null @@ -1,1640 +0,0 @@ -/* -LodePNG version 20120729 - -Copyright (c) 2005-2012 Lode Vandevenne - -This software is provided 'as-is', without any express or implied -warranty. In no event will the authors be held liable for any damages -arising from the use of this software. - -Permission is granted to anyone to use this software for any purpose, -including commercial applications, and to alter it and redistribute it -freely, subject to the following restrictions: - - 1. The origin of this software must not be misrepresented; you must not - claim that you wrote the original software. If you use this software - in a product, an acknowledgment in the product documentation would be - appreciated but is not required. - - 2. Altered source versions must be plainly marked as such, and must not be - misrepresented as being the original software. - - 3. This notice may not be removed or altered from any source - distribution. -*/ - -#ifndef LODEPNG_H -#define LODEPNG_H - -#define LODEPNG_NO_COMPILE_ENCODER -#define LODEPNG_NO_COMPILE_ANCILLARY_CHUNKS -#define LODEPNG_NO_COMPILE_CPP -#define LODEPNG_NO_COMPILE_DISK -#define LODEPNG_NO_COMPILE_ZLIB -#define LODEPNG_NO_COMPILE_CPP - -#include /*for size_t*/ - -#ifdef __cplusplus -#include -#include -#endif /*__cplusplus*/ - -/* -The following #defines are used to create code sections. They can be disabled -to disable code sections, which can give faster compile time and smaller binary. -The "NO_COMPILE" defines are designed to be used to pass as defines to the -compiler command to disable them without modifying this header, e.g. --DLODEPNG_NO_COMPILE_ZLIB for gcc. -*/ -/*deflate&zlib. If disabled, you need to define two zlib functions, see documtation of LODEPNG_CUSTOM_ZLIB_... below*/ -#ifndef LODEPNG_NO_COMPILE_ZLIB -#define LODEPNG_COMPILE_ZLIB -#endif -/*png encoder and png decoder*/ -#ifndef LODEPNG_NO_COMPILE_PNG -#define LODEPNG_COMPILE_PNG -#endif -/*deflate&zlib decoder and png decoder*/ -#ifndef LODEPNG_NO_COMPILE_DECODER -#define LODEPNG_COMPILE_DECODER -#endif -/*deflate&zlib encoder and png encoder*/ -#ifndef LODEPNG_NO_COMPILE_ENCODER -#define LODEPNG_COMPILE_ENCODER -#endif -/*the optional built in harddisk file loading and saving functions*/ -#ifndef LODEPNG_NO_COMPILE_DISK -#define LODEPNG_COMPILE_DISK -#endif -/*support for chunks other than IHDR, IDAT, PLTE, tRNS, IEND: ancillary and unknown chunks*/ -#ifndef LODEPNG_NO_COMPILE_ANCILLARY_CHUNKS -#define LODEPNG_COMPILE_ANCILLARY_CHUNKS -#endif -/*ability to convert error numerical codes to English text string*/ -#ifndef LODEPNG_NO_COMPILE_ERROR_TEXT -#define LODEPNG_COMPILE_ERROR_TEXT -#endif -/*compile the C++ version (you can disable the C++ wrapper here even when compiling for C++)*/ -#ifdef __cplusplus -#ifndef LODEPNG_NO_COMPILE_CPP -#define LODEPNG_COMPILE_CPP -#endif -#endif - -/* -custom zlib decoder (if LODEPNG_COMPILE_ZLIB is disabled, this is ignored, always treated as "1"): -0: not custom, use LodePNG's zlib decoder -1: allow using custom zlib decoder with a setting ---> you must then provide following function in your source files that LodePNG will link to: - unsigned lodepng_custom_inflate(unsigned char**, size_t*, const unsigned char*, size_t, - const LodePNGDecompressSettings*) -2: allow using custom deflate decoder with a setting ---> you must then provide following function in your source files that LodePNG will link to: - unsigned lodepng_custom_zlib_decompress(unsigned char**, size_t*, const unsigned char*, size_t, - const LodePNGDecompressSettings*) -*/ -#ifndef LODEPNG_OVERRIDE_CUSTOM_ZLIB_DECODER -#define LODEPNG_CUSTOM_ZLIB_DECODER 0 -#else -#define LODEPNG_CUSTOM_ZLIB_DECODER LODEPNG_OVERRIDE_CUSTOM_ZLIB_DECODER -#endif - -/* -custom zlib encoder (if LODEPNG_COMPILE_ZLIB is disabled, this is ignored, always treated as "1"): -0: not custom, use LodePNG's zlib encoder -1: allow using custom zlib encoder with a setting ---> you must then provide following function in your source files that LodePNG will link to: - unsigned lodepng_custom_deflate(unsigned char**, size_t*, const unsigned char*, size_t, - const LodePNGCompressSettings*) -2: allow using custom deflate encoder with a setting ---> you must then provide following function in your source files that LodePNG will link to: - unsigned lodepng_custom_zlib_compress(unsigned char**, size_t*, const unsigned char*, size_t, - const LodePNGCompressSettings*) -*/ -#ifndef LODEPNG_OVERRIDE_CUSTOM_ZLIB_ENCODER -#define LODEPNG_CUSTOM_ZLIB_ENCODER 0 -#else -#define LODEPNG_CUSTOM_ZLIB_ENCODER LODEPNG_OVERRIDE_CUSTOM_ZLIB_ENCODER -#endif - -#ifdef LODEPNG_COMPILE_PNG -/*The PNG color types (also used for raw).*/ -typedef enum LodePNGColorType -{ - LCT_GREY = 0, /*greyscale: 1,2,4,8,16 bit*/ - LCT_RGB = 2, /*RGB: 8,16 bit*/ - LCT_PALETTE = 3, /*palette: 1,2,4,8 bit*/ - LCT_GREY_ALPHA = 4, /*greyscale with alpha: 8,16 bit*/ - LCT_RGBA = 6 /*RGB with alpha: 8,16 bit*/ -} LodePNGColorType; - -#ifdef LODEPNG_COMPILE_DECODER -/* -Converts PNG data in memory to raw pixel data. -out: Output parameter. Pointer to buffer that will contain the raw pixel data. - After decoding, its size is w * h * (bytes per pixel) bytes larger than - initially. Bytes per pixel depends on colortype and bitdepth. - Must be freed after usage with free(*out). -w: Output parameter. Pointer to width of pixel data. -h: Output parameter. Pointer to height of pixel data. -in: Memory buffer with the PNG file. -insize: size of the in buffer. -colortype: the desired color type for the raw output image. See explanation on PNG color types. -bitdepth: the desired bit depth for the raw output image. See explanation on PNG color types. -Return value: LodePNG error code (0 means no error). -*/ -unsigned lodepng_decode_memory(unsigned char** out, unsigned* w, unsigned* h, - const unsigned char* in, size_t insize, - LodePNGColorType colortype, unsigned bitdepth); - -/*Same as lodepng_decode_memory, but always decodes to 32-bit RGBA raw image*/ -unsigned lodepng_decode32(unsigned char** out, unsigned* w, unsigned* h, - const unsigned char* in, size_t insize); - -/*Same as lodepng_decode_memory, but always decodes to 24-bit RGB raw image*/ -unsigned lodepng_decode24(unsigned char** out, unsigned* w, unsigned* h, - const unsigned char* in, size_t insize); - -#ifdef LODEPNG_COMPILE_DISK -/* -Load PNG from disk, from file with given name. -Same as the other decode functions, but instead takes a filename as input. -*/ -unsigned lodepng_decode_file(unsigned char** out, unsigned* w, unsigned* h, - const char* filename, - LodePNGColorType colortype, unsigned bitdepth); - -/*Same as lodepng_decode_file, but always decodes to 32-bit RGBA raw image.*/ -unsigned lodepng_decode32_file(unsigned char** out, unsigned* w, unsigned* h, - const char* filename); - -/*Same as lodepng_decode_file, but always decodes to 24-bit RGB raw image.*/ -unsigned lodepng_decode24_file(unsigned char** out, unsigned* w, unsigned* h, - const char* filename); -#endif /*LODEPNG_COMPILE_DISK*/ -#endif /*LODEPNG_COMPILE_DECODER*/ - - -#ifdef LODEPNG_COMPILE_ENCODER -/* -Converts raw pixel data into a PNG image in memory. The colortype and bitdepth - of the output PNG image cannot be chosen, they are automatically determined - by the colortype, bitdepth and content of the input pixel data. -out: Output parameter. Pointer to buffer that will contain the raw pixel data. - Must be freed after usage with free(*out). -outsize: Output parameter. Pointer to the size in bytes of the out buffer. -image: The raw pixel data to encode. The size of this buffer should be - w * h * (bytes per pixel), bytes per pixel depends on colortype and bitdepth. -w: width of the raw pixel data in pixels. -h: height of the raw pixel data in pixels. -colortype: the color type of the raw input image. See explanation on PNG color types. -bitdepth: the bit depth of the raw input image. See explanation on PNG color types. -Return value: LodePNG error code (0 means no error). -*/ -unsigned lodepng_encode_memory(unsigned char** out, size_t* outsize, - const unsigned char* image, unsigned w, unsigned h, - LodePNGColorType colortype, unsigned bitdepth); - -/*Same as lodepng_encode_memory, but always encodes from 32-bit RGBA raw image.*/ -unsigned lodepng_encode32(unsigned char** out, size_t* outsize, - const unsigned char* image, unsigned w, unsigned h); - -/*Same as lodepng_encode_memory, but always encodes from 24-bit RGB raw image.*/ -unsigned lodepng_encode24(unsigned char** out, size_t* outsize, - const unsigned char* image, unsigned w, unsigned h); - -#ifdef LODEPNG_COMPILE_DISK -/* -Converts raw pixel data into a PNG file on disk. -Same as the other encode functions, but instead takes a filename as output. -NOTE: This overwrites existing files without warning! -*/ -unsigned lodepng_encode_file(const char* filename, - const unsigned char* image, unsigned w, unsigned h, - LodePNGColorType colortype, unsigned bitdepth); - -/*Same as lodepng_encode_file, but always encodes from 32-bit RGBA raw image.*/ -unsigned lodepng_encode32_file(const char* filename, - const unsigned char* image, unsigned w, unsigned h); - -/*Same as lodepng_encode_file, but always encodes from 24-bit RGB raw image.*/ -unsigned lodepng_encode24_file(const char* filename, - const unsigned char* image, unsigned w, unsigned h); -#endif /*LODEPNG_COMPILE_DISK*/ -#endif /*LODEPNG_COMPILE_ENCODER*/ - - -#ifdef LODEPNG_COMPILE_CPP -namespace lodepng -{ -#ifdef LODEPNG_COMPILE_DECODER -/*Same as lodepng_decode_memory, but decodes to an std::vector.*/ -unsigned decode(std::vector& out, unsigned& w, unsigned& h, - const unsigned char* in, size_t insize, - LodePNGColorType colortype = LCT_RGBA, unsigned bitdepth = 8); -unsigned decode(std::vector& out, unsigned& w, unsigned& h, - const std::vector& in, - LodePNGColorType colortype = LCT_RGBA, unsigned bitdepth = 8); -#ifdef LODEPNG_COMPILE_DISK -/* -Converts PNG file from disk to raw pixel data in memory. -Same as the other decode functions, but instead takes a filename as input. -*/ -unsigned decode(std::vector& out, unsigned& w, unsigned& h, - const std::string& filename, - LodePNGColorType colortype = LCT_RGBA, unsigned bitdepth = 8); -#endif //LODEPNG_COMPILE_DISK -#endif //LODEPNG_COMPILE_DECODER - -#ifdef LODEPNG_COMPILE_ENCODER -/*Same as lodepng_encode_memory, but encodes to an std::vector.*/ -unsigned encode(std::vector& out, - const unsigned char* in, unsigned w, unsigned h, - LodePNGColorType colortype = LCT_RGBA, unsigned bitdepth = 8); -unsigned encode(std::vector& out, - const std::vector& in, unsigned w, unsigned h, - LodePNGColorType colortype = LCT_RGBA, unsigned bitdepth = 8); -#ifdef LODEPNG_COMPILE_DISK -/* -Converts 32-bit RGBA raw pixel data into a PNG file on disk. -Same as the other encode functions, but instead takes a filename as output. -NOTE: This overwrites existing files without warning! -*/ -unsigned encode(const std::string& filename, - const unsigned char* in, unsigned w, unsigned h, - LodePNGColorType colortype = LCT_RGBA, unsigned bitdepth = 8); -unsigned encode(const std::string& filename, - const std::vector& in, unsigned w, unsigned h, - LodePNGColorType colortype = LCT_RGBA, unsigned bitdepth = 8); -#endif //LODEPNG_COMPILE_DISK -#endif //LODEPNG_COMPILE_ENCODER -} //namespace lodepng -#endif /*LODEPNG_COMPILE_CPP*/ -#endif /*LODEPNG_COMPILE_PNG*/ - -#ifdef LODEPNG_COMPILE_ERROR_TEXT -/*Returns an English description of the numerical error code.*/ -const char* lodepng_error_text(unsigned code); -#endif /*LODEPNG_COMPILE_ERROR_TEXT*/ - -#ifdef LODEPNG_COMPILE_DECODER -/*Settings for zlib decompression*/ -typedef struct LodePNGDecompressSettings -{ - unsigned ignore_adler32; /*if 1, continue and don't give an error message if the Adler32 checksum is corrupted*/ - unsigned custom_decoder; /*use custom decoder if LODEPNG_CUSTOM_ZLIB_DECODER and LODEPNG_COMPILE_ZLIB are enabled*/ -} LodePNGDecompressSettings; - -extern const LodePNGDecompressSettings lodepng_default_decompress_settings; -void lodepng_decompress_settings_init(LodePNGDecompressSettings* settings); -#endif /*LODEPNG_COMPILE_DECODER*/ - -/* -Settings for zlib compression. Tweaking these settings tweaks the balance -between speed and compression ratio. -*/ -typedef struct LodePNGCompressSettings /*deflate = compress*/ -{ - /*LZ77 related settings*/ - unsigned btype; /*the block type for LZ (0, 1, 2 or 3, see zlib standard). Should be 2 for proper compression.*/ - unsigned use_lz77; /*whether or not to use LZ77. Should be 1 for proper compression.*/ - unsigned windowsize; /*the maximum is 32768, higher gives more compression but is slower. Typical value: 2048.*/ - unsigned custom_encoder; /*use custom encoder if LODEPNG_CUSTOM_ZLIB_DECODER and LODEPNG_COMPILE_ZLIB are enabled*/ -} LodePNGCompressSettings; - -#ifdef LODEPNG_COMPILE_ENCODER -extern const LodePNGCompressSettings lodepng_default_compress_settings; -void lodepng_compress_settings_init(LodePNGCompressSettings* settings); -#endif /*LODEPNG_COMPILE_ENCODER*/ - -#ifdef LODEPNG_COMPILE_PNG -/* -Color mode of an image. Contains all information required to decode the pixel -bits to RGBA colors. This information is the same as used in the PNG file -format, and is used both for PNG and raw image data in LodePNG. -*/ -typedef struct LodePNGColorMode -{ - /*header (IHDR)*/ - LodePNGColorType colortype; /*color type, see PNG standard or documentation further in this header file*/ - unsigned bitdepth; /*bits per sample, see PNG standard or documentation further in this header file*/ - - /* - palette (PLTE and tRNS) - - Dynamically allocated with the colors of the palette, including alpha. - When encoding a PNG, to store your colors in the palette of the LodePNGColorMode, first use - lodepng_palette_clear, then for each color use lodepng_palette_add. - If you encode an image without alpha with palette, don't forget to put value 255 in each A byte of the palette. - - When decoding, by default you can ignore this palette, since LodePNG already - fills the palette colors in the pixels of the raw RGBA output. - - The palette is only supported for color type 3. - */ - unsigned char* palette; /*palette in RGBARGBA... order*/ - size_t palettesize; /*palette size in number of colors (amount of bytes is 4 * palettesize)*/ - - /* - transparent color key (tRNS) - - This color uses the same bit depth as the bitdepth value in this struct, which can be 1-bit to 16-bit. - For greyscale PNGs, r, g and b will all 3 be set to the same. - - When decoding, by default you can ignore this information, since LodePNG sets - pixels with this key to transparent already in the raw RGBA output. - - The color key is only supported for color types 0 and 2. - */ - unsigned key_defined; /*is a transparent color key given? 0 = false, 1 = true*/ - unsigned key_r; /*red/greyscale component of color key*/ - unsigned key_g; /*green component of color key*/ - unsigned key_b; /*blue component of color key*/ -} LodePNGColorMode; - -/*init, cleanup and copy functions to use with this struct*/ -void lodepng_color_mode_init(LodePNGColorMode* info); -void lodepng_color_mode_cleanup(LodePNGColorMode* info); -/*return value is error code (0 means no error)*/ -unsigned lodepng_color_mode_copy(LodePNGColorMode* dest, const LodePNGColorMode* source); - -void lodepng_palette_clear(LodePNGColorMode* info); -/*add 1 color to the palette*/ -unsigned lodepng_palette_add(LodePNGColorMode* info, - unsigned char r, unsigned char g, unsigned char b, unsigned char a); - -/*get the total amount of bits per pixel, based on colortype and bitdepth in the struct*/ -unsigned lodepng_get_bpp(const LodePNGColorMode* info); -/*get the amount of color channels used, based on colortype in the struct. -If a palette is used, it counts as 1 channel.*/ -unsigned lodepng_get_channels(const LodePNGColorMode* info); -/*is it a greyscale type? (only colortype 0 or 4)*/ -unsigned lodepng_is_greyscale_type(const LodePNGColorMode* info); -/*has it got an alpha channel? (only colortype 2 or 6)*/ -unsigned lodepng_is_alpha_type(const LodePNGColorMode* info); -/*has it got a palette? (only colortype 3)*/ -unsigned lodepng_is_palette_type(const LodePNGColorMode* info); -/*only returns true if there is a palette and there is a value in the palette with alpha < 255. -Loops through the palette to check this.*/ -unsigned lodepng_has_palette_alpha(const LodePNGColorMode* info); -/* -Check if the given color info indicates the possibility of having non-opaque pixels in the PNG image. -Returns true if the image can have translucent or invisible pixels (it still be opaque if it doesn't use such pixels). -Returns false if the image can only have opaque pixels. -In detail, it returns true only if it's a color type with alpha, or has a palette with non-opaque values, -or if "key_defined" is true. -*/ -unsigned lodepng_can_have_alpha(const LodePNGColorMode* info); -/*Returns the byte size of a raw image buffer with given width, height and color mode*/ -size_t lodepng_get_raw_size(unsigned w, unsigned h, const LodePNGColorMode* color); - -#ifdef LODEPNG_COMPILE_ANCILLARY_CHUNKS -/*The information of a Time chunk in PNG.*/ -typedef struct LodePNGTime -{ - unsigned year; /*2 bytes used (0-65535)*/ - unsigned month; /*1-12*/ - unsigned day; /*1-31*/ - unsigned hour; /*0-23*/ - unsigned minute; /*0-59*/ - unsigned second; /*0-60 (to allow for leap seconds)*/ -} LodePNGTime; -#endif /*LODEPNG_COMPILE_ANCILLARY_CHUNKS*/ - -/*Information about the PNG image, except pixels, width and height.*/ -typedef struct LodePNGInfo -{ - /*header (IHDR), palette (PLTE) and transparency (tRNS) chunks*/ - unsigned compression_method;/*compression method of the original file. Always 0.*/ - unsigned filter_method; /*filter method of the original file*/ - unsigned interlace_method; /*interlace method of the original file*/ - LodePNGColorMode color; /*color type and bits, palette and transparency of the PNG file*/ - -#ifdef LODEPNG_COMPILE_ANCILLARY_CHUNKS - /* - suggested background color chunk (bKGD) - This color uses the same color mode as the PNG (except alpha channel), which can be 1-bit to 16-bit. - - For greyscale PNGs, r, g and b will all 3 be set to the same. When encoding - the encoder writes the red one. For palette PNGs: When decoding, the RGB value - will be stored, not a palette index. But when encoding, specify the index of - the palette in background_r, the other two are then ignored. - - The decoder does not use this background color to edit the color of pixels. - */ - unsigned background_defined; /*is a suggested background color given?*/ - unsigned background_r; /*red component of suggested background color*/ - unsigned background_g; /*green component of suggested background color*/ - unsigned background_b; /*blue component of suggested background color*/ - - /* - non-international text chunks (tEXt and zTXt) - - The char** arrays each contain num strings. The actual messages are in - text_strings, while text_keys are keywords that give a short description what - the actual text represents, e.g. Title, Author, Description, or anything else. - - A keyword is minimum 1 character and maximum 79 characters long. It's - discouraged to use a single line length longer than 79 characters for texts. - - Don't allocate these text buffers yourself. Use the init/cleanup functions - correctly and use lodepng_add_text and lodepng_clear_text. - */ - size_t text_num; /*the amount of texts in these char** buffers (there may be more texts in itext)*/ - char** text_keys; /*the keyword of a text chunk (e.g. "Comment")*/ - char** text_strings; /*the actual text*/ - - /* - international text chunks (iTXt) - Similar to the non-international text chunks, but with additional strings - "langtags" and "transkeys". - */ - size_t itext_num; /*the amount of international texts in this PNG*/ - char** itext_keys; /*the English keyword of the text chunk (e.g. "Comment")*/ - char** itext_langtags; /*language tag for this text's language, ISO/IEC 646 string, e.g. ISO 639 language tag*/ - char** itext_transkeys; /*keyword translated to the international language - UTF-8 string*/ - char** itext_strings; /*the actual international text - UTF-8 string*/ - - /*time chunk (tIME)*/ - unsigned time_defined; /*set to 1 to make the encoder generate a tIME chunk*/ - LodePNGTime time; - - /*phys chunk (pHYs)*/ - unsigned phys_defined; /*if 0, there is no pHYs chunk and the values below are undefined, if 1 else there is one*/ - unsigned phys_x; /*pixels per unit in x direction*/ - unsigned phys_y; /*pixels per unit in y direction*/ - unsigned phys_unit; /*may be 0 (unknown unit) or 1 (metre)*/ - - /* - unknown chunks - There are 3 buffers, one for each position in the PNG where unknown chunks can appear - each buffer contains all unknown chunks for that position consecutively - The 3 buffers are the unknown chunks between certain critical chunks: - 0: IHDR-PLTE, 1: PLTE-IDAT, 2: IDAT-IEND - Do not allocate or traverse this data yourself. Use the chunk traversing functions declared - later, such as lodepng_chunk_next and lodepng_chunk_append, to read/write this struct. - */ - unsigned char* unknown_chunks_data[3]; - size_t unknown_chunks_size[3]; /*size in bytes of the unknown chunks, given for protection*/ -#endif /*LODEPNG_COMPILE_ANCILLARY_CHUNKS*/ -} LodePNGInfo; - -/*init, cleanup and copy functions to use with this struct*/ -void lodepng_info_init(LodePNGInfo* info); -void lodepng_info_cleanup(LodePNGInfo* info); -/*return value is error code (0 means no error)*/ -unsigned lodepng_info_copy(LodePNGInfo* dest, const LodePNGInfo* source); - -#ifdef LODEPNG_COMPILE_ANCILLARY_CHUNKS -void lodepng_clear_text(LodePNGInfo* info); /*use this to clear the texts again after you filled them in*/ -unsigned lodepng_add_text(LodePNGInfo* info, const char* key, const char* str); /*push back both texts at once*/ - -void lodepng_clear_itext(LodePNGInfo* info); /*use this to clear the itexts again after you filled them in*/ -unsigned lodepng_add_itext(LodePNGInfo* info, const char* key, const char* langtag, - const char* transkey, const char* str); /*push back the 4 texts of 1 chunk at once*/ -#endif /*LODEPNG_COMPILE_ANCILLARY_CHUNKS*/ - -/* -Converts raw buffer from one color type to another color type, based on -LodePNGColorMode structs to describe the input and output color type. -See the reference manual at the end of this header file to see which color conversions are supported. -return value = LodePNG error code (0 if all went ok, an error if the conversion isn't supported) -The out buffer must have size (w * h * bpp + 7) / 8, where bpp is the bits per pixel -of the output color type (lodepng_get_bpp) -*/ -unsigned lodepng_convert(unsigned char* out, const unsigned char* in, - LodePNGColorMode* mode_out, LodePNGColorMode* mode_in, - unsigned w, unsigned h); - - -#ifdef LODEPNG_COMPILE_DECODER -/* -Settings for the decoder. This contains settings for the PNG and the Zlib -decoder, but not the Info settings from the Info structs. -*/ -typedef struct LodePNGDecoderSettings -{ - LodePNGDecompressSettings zlibsettings; /*in here is the setting to ignore Adler32 checksums*/ - - unsigned ignore_crc; /*ignore CRC checksums*/ - unsigned color_convert; /*whether to convert the PNG to the color type you want. Default: yes*/ - -#ifdef LODEPNG_COMPILE_ANCILLARY_CHUNKS - unsigned read_text_chunks; /*if false but remember_unknown_chunks is true, they're stored in the unknown chunks*/ - /*store all bytes from unknown chunks in the LodePNGInfo (off by default, useful for a png editor)*/ - unsigned remember_unknown_chunks; -#endif /*LODEPNG_COMPILE_ANCILLARY_CHUNKS*/ -} LodePNGDecoderSettings; - -void lodepng_decoder_settings_init(LodePNGDecoderSettings* settings); -#endif /*LODEPNG_COMPILE_DECODER*/ - -#ifdef LODEPNG_COMPILE_ENCODER -/*automatically use color type with less bits per pixel if losslessly possible. Default: AUTO*/ -typedef enum LodePNGFilterStrategy -{ - LFS_HEURISTIC, /*official PNG heuristic*/ - LFS_ZERO, /*every filter at zero*/ - LFS_MINSUM, /*like the official PNG heuristic, but use minimal sum always, including palette and low bitdepth images*/ - /* - Brute-force-search PNG filters by compressing each filter for each scanline. - This gives better compression, at the cost of being super slow. Experimental! - If you enable this, also set zlibsettings.windowsize to 32768 and choose an - optimal color mode for the PNG image for best compression. Default: 0 (false). - */ - LFS_BRUTE_FORCE, - LFS_PREDEFINED /*use predefined_filters buffer: you specify the filter type for each scanline*/ -} LodePNGFilterStrategy; - -/*automatically use color type with less bits per pixel if losslessly possible. Default: LAC_AUTO*/ -typedef enum LodePNGAutoConvert -{ - LAC_NO, /*use color type user requested*/ - LAC_ALPHA, /*use color type user requested, but if only opaque pixels and RGBA or grey+alpha, use RGB or grey*/ - LAC_AUTO, /*use PNG color type that can losslessly represent the uncompressed image the smallest possible*/ - /* - like AUTO, but do not choose 1, 2 or 4 bit per pixel types. - sometimes a PNG image compresses worse if less than 8 bits per pixels. - */ - LAC_AUTO_NO_NIBBLES -} LodePNGAutoConvert; - - -/*Settings for the encoder.*/ -typedef struct LodePNGEncoderSettings -{ - LodePNGCompressSettings zlibsettings; /*settings for the zlib encoder, such as window size, ...*/ - - LodePNGAutoConvert auto_convert; /*how to automatically choose output PNG color type, if at all*/ - - LodePNGFilterStrategy filter_strategy; - - /*used if filter_strategy is LFS_PREDEFINED. In that case, this must point to a buffer with - the same length as the amount of scanlines in the image, and each value must <= 5. You - have to cleanup this buffer, LodePNG will never free it.*/ - unsigned char* predefined_filters; - - /*force creating a PLTE chunk if colortype is 2 or 6 (= a suggested palette). - If colortype is 3, PLTE is _always_ created.*/ - unsigned force_palette; -#ifdef LODEPNG_COMPILE_ANCILLARY_CHUNKS - /*add LodePNG identifier and version as a text chunk, for debugging*/ - unsigned add_id; - /*encode text chunks as zTXt chunks instead of tEXt chunks, and use compression in iTXt chunks*/ - unsigned text_compression; -#endif /*LODEPNG_COMPILE_ANCILLARY_CHUNKS*/ -} LodePNGEncoderSettings; - -void lodepng_encoder_settings_init(LodePNGEncoderSettings* settings); -#endif /*LODEPNG_COMPILE_ENCODER*/ - - -#if defined(LODEPNG_COMPILE_DECODER) || defined(LODEPNG_COMPILE_ENCODER) -/*The settings, state and information for extended encoding and decoding.*/ -typedef struct LodePNGState -{ -#ifdef LODEPNG_COMPILE_DECODER - LodePNGDecoderSettings decoder; /*the decoding settings*/ -#endif /*LODEPNG_COMPILE_DECODER*/ -#ifdef LODEPNG_COMPILE_ENCODER - LodePNGEncoderSettings encoder; /*the encoding settings*/ -#endif /*LODEPNG_COMPILE_ENCODER*/ - LodePNGColorMode info_raw; /*specifies the format in which you would like to get the raw pixel buffer*/ - LodePNGInfo info_png; /*info of the PNG image obtained after decoding*/ - unsigned error; -#ifdef LODEPNG_COMPILE_CPP - //For the lodepng::State subclass. - virtual ~LodePNGState(){} -#endif -} LodePNGState; - -/*init, cleanup and copy functions to use with this struct*/ -void lodepng_state_init(LodePNGState* state); -void lodepng_state_cleanup(LodePNGState* state); -void lodepng_state_copy(LodePNGState* dest, const LodePNGState* source); -#endif /* defined(LODEPNG_COMPILE_DECODER) || defined(LODEPNG_COMPILE_ENCODER) */ - -#ifdef LODEPNG_COMPILE_DECODER -/* -Same as lodepng_decode_memory, but uses a LodePNGState to allow custom settings and -getting much more information about the PNG image and color mode. -*/ -unsigned lodepng_decode(unsigned char** out, unsigned* w, unsigned* h, - LodePNGState* state, - const unsigned char* in, size_t insize); - -/* -Read the PNG header, but not the actual data. This returns only the information -that is in the header chunk of the PNG, such as width, height and color type. The -information is placed in the info_png field of the LodePNGState. -*/ -unsigned lodepng_inspect(unsigned* w, unsigned* h, - LodePNGState* state, - const unsigned char* in, size_t insize); -#endif /*LODEPNG_COMPILE_DECODER*/ - - -#ifdef LODEPNG_COMPILE_ENCODER -/*This function allocates the out buffer with standard malloc and stores the size in *outsize.*/ -unsigned lodepng_encode(unsigned char** out, size_t* outsize, - const unsigned char* image, unsigned w, unsigned h, - LodePNGState* state); -#endif /*LODEPNG_COMPILE_ENCODER*/ - -/* -The lodepng_chunk functions are normally not needed, except to traverse the -unknown chunks stored in the LodePNGInfo struct, or add new ones to it. -It also allows traversing the chunks of an encoded PNG file yourself. - -PNG standard chunk naming conventions: -First byte: uppercase = critical, lowercase = ancillary -Second byte: uppercase = public, lowercase = private -Third byte: must be uppercase -Fourth byte: uppercase = unsafe to copy, lowercase = safe to copy -*/ - -/*get the length of the data of the chunk. Total chunk length has 12 bytes more.*/ -unsigned lodepng_chunk_length(const unsigned char* chunk); - -/*puts the 4-byte type in null terminated string*/ -void lodepng_chunk_type(char type[5], const unsigned char* chunk); - -/*check if the type is the given type*/ -unsigned char lodepng_chunk_type_equals(const unsigned char* chunk, const char* type); - -/*0: it's one of the critical chunk types, 1: it's an ancillary chunk (see PNG standard)*/ -unsigned char lodepng_chunk_ancillary(const unsigned char* chunk); - -/*0: public, 1: private (see PNG standard)*/ -unsigned char lodepng_chunk_private(const unsigned char* chunk); - -/*0: the chunk is unsafe to copy, 1: the chunk is safe to copy (see PNG standard)*/ -unsigned char lodepng_chunk_safetocopy(const unsigned char* chunk); - -/*get pointer to the data of the chunk, where the input points to the header of the chunk*/ -unsigned char* lodepng_chunk_data(unsigned char* chunk); -const unsigned char* lodepng_chunk_data_const(const unsigned char* chunk); - -/*returns 0 if the crc is correct, 1 if it's incorrect (0 for OK as usual!)*/ -unsigned lodepng_chunk_check_crc(const unsigned char* chunk); - -/*generates the correct CRC from the data and puts it in the last 4 bytes of the chunk*/ -void lodepng_chunk_generate_crc(unsigned char* chunk); - -/*iterate to next chunks. don't use on IEND chunk, as there is no next chunk then*/ -unsigned char* lodepng_chunk_next(unsigned char* chunk); -const unsigned char* lodepng_chunk_next_const(const unsigned char* chunk); - -/* -Appends chunk to the data in out. The given chunk should already have its chunk header. -The out variable and outlength are updated to reflect the new reallocated buffer. -Returns error code (0 if it went ok) -*/ -unsigned lodepng_chunk_append(unsigned char** out, size_t* outlength, const unsigned char* chunk); - -/* -Appends new chunk to out. The chunk to append is given by giving its length, type -and data separately. The type is a 4-letter string. -The out variable and outlength are updated to reflect the new reallocated buffer. -Returne error code (0 if it went ok) -*/ -unsigned lodepng_chunk_create(unsigned char** out, size_t* outlength, unsigned length, - const char* type, const unsigned char* data); - - -/*Calculate CRC32 of buffer*/ -unsigned lodepng_crc32(const unsigned char* buf, size_t len); -#endif /*LODEPNG_COMPILE_PNG*/ - - -#ifdef LODEPNG_COMPILE_ZLIB -/* -This zlib part can be used independently to zlib compress and decompress a -buffer. It cannot be used to create gzip files however, and it only supports the -part of zlib that is required for PNG, it does not support dictionaries. -*/ - -#ifdef LODEPNG_COMPILE_DECODER -/*Inflate a buffer. Inflate is the decompression step of deflate. Out buffer must be freed after use.*/ -unsigned lodepng_inflate(unsigned char** out, size_t* outsize, - const unsigned char* in, size_t insize, - const LodePNGDecompressSettings* settings); - -/* -Decompresses Zlib data. Reallocates the out buffer and appends the data. The -data must be according to the zlib specification. -Either, *out must be NULL and *outsize must be 0, or, *out must be a valid -buffer and *outsize its size in bytes. out must be freed by user after usage. -*/ -unsigned lodepng_zlib_decompress(unsigned char** out, size_t* outsize, - const unsigned char* in, size_t insize, - const LodePNGDecompressSettings* settings); -#endif /*LODEPNG_COMPILE_DECODER*/ - -#ifdef LODEPNG_COMPILE_ENCODER -/* -Compresses data with Zlib. Reallocates the out buffer and appends the data. -Zlib adds a small header and trailer around the deflate data. -The data is output in the format of the zlib specification. -Either, *out must be NULL and *outsize must be 0, or, *out must be a valid -buffer and *outsize its size in bytes. out must be freed by user after usage. -*/ -unsigned lodepng_zlib_compress(unsigned char** out, size_t* outsize, - const unsigned char* in, size_t insize, - const LodePNGCompressSettings* settings); - -/* -Find length-limited Huffman code for given frequencies. This function is in the -public interface only for tests, it's used internally by lodepng_deflate. -*/ -unsigned lodepng_huffman_code_lengths(unsigned* lengths, const unsigned* frequencies, - size_t numcodes, unsigned maxbitlen); - -/*Compress a buffer with deflate. See RFC 1951. Out buffer must be freed after use.*/ -unsigned lodepng_deflate(unsigned char** out, size_t* outsize, - const unsigned char* in, size_t insize, - const LodePNGCompressSettings* settings); - -#endif /*LODEPNG_COMPILE_ENCODER*/ -#endif /*LODEPNG_COMPILE_ZLIB*/ - -#ifdef LODEPNG_COMPILE_DISK -/* -Load a file from disk into buffer. The function allocates the out buffer, and -after usage you should free it. -out: output parameter, contains pointer to loaded buffer. -outsize: output parameter, size of the allocated out buffer -filename: the path to the file to load -return value: error code (0 means ok) -*/ -unsigned lodepng_load_file(unsigned char** out, size_t* outsize, const char* filename); - -/* -Save a file from buffer to disk. Warning, if it exists, this function overwrites -the file without warning! -buffer: the buffer to write -buffersize: size of the buffer to write -filename: the path to the file to save to -return value: error code (0 means ok) -*/ -unsigned lodepng_save_file(const unsigned char* buffer, size_t buffersize, const char* filename); -#endif /*LODEPNG_COMPILE_DISK*/ - -#ifdef LODEPNG_COMPILE_CPP -//The LodePNG C++ wrapper uses std::vectors instead of manually allocated memory buffers. -namespace lodepng -{ -#ifdef LODEPNG_COMPILE_PNG -class State : public LodePNGState -{ - public: - State(); - State(const State& other); - virtual ~State(); - State& operator=(const State& other); -}; - -#ifdef LODEPNG_COMPILE_DECODER -//Same as other lodepng::decode, but using a State for more settings and information. -unsigned decode(std::vector& out, unsigned& w, unsigned& h, - State& state, - const unsigned char* in, size_t insize); -unsigned decode(std::vector& out, unsigned& w, unsigned& h, - State& state, - const std::vector& in); -#endif /*LODEPNG_COMPILE_DECODER*/ - -#ifdef LODEPNG_COMPILE_ENCODER -//Same as other lodepng::encode, but using a State for more settings and information. -unsigned encode(std::vector& out, - const unsigned char* in, unsigned w, unsigned h, - State& state); -unsigned encode(std::vector& out, - const std::vector& in, unsigned w, unsigned h, - State& state); -#endif /*LODEPNG_COMPILE_ENCODER*/ - - -#ifdef LODEPNG_COMPILE_DISK -/* -Load a file from disk into an std::vector. If the vector is empty, then either -the file doesn't exist or is an empty file. -*/ -void load_file(std::vector& buffer, const std::string& filename); - -/* -Save the binary data in an std::vector to a file on disk. The file is overwritten -without warning. -*/ -void save_file(const std::vector& buffer, const std::string& filename); -#endif //LODEPNG_COMPILE_DISK -#endif //LODEPNG_COMPILE_PNG - -#ifdef LODEPNG_COMPILE_ZLIB -#ifdef LODEPNG_COMPILE_DECODER -//Zlib-decompress an unsigned char buffer -unsigned decompress(std::vector& out, const unsigned char* in, size_t insize, - const LodePNGDecompressSettings& settings = lodepng_default_decompress_settings); - -//Zlib-decompress an std::vector -unsigned decompress(std::vector& out, const std::vector& in, - const LodePNGDecompressSettings& settings = lodepng_default_decompress_settings); -#endif //LODEPNG_COMPILE_DECODER - -#ifdef LODEPNG_COMPILE_ENCODER -//Zlib-compress an unsigned char buffer -unsigned compress(std::vector& out, const unsigned char* in, size_t insize, - const LodePNGCompressSettings& settings = lodepng_default_compress_settings); - -//Zlib-compress an std::vector -unsigned compress(std::vector& out, const std::vector& in, - const LodePNGCompressSettings& settings = lodepng_default_compress_settings); -#endif //LODEPNG_COMPILE_ENCODER -#endif //LODEPNG_COMPILE_ZLIB -} //namespace lodepng -#endif /*LODEPNG_COMPILE_CPP*/ - -/* -TODO: -[.] test if there are no memory leaks or security exploits - done a lot but needs to be checked often -[.] check compatibility with vareous compilers - done but needs to be redone for every newer version -[X] converting color to 16-bit per channel types -[ ] read all public PNG chunk types (but never let the color profile and gamma ones touch RGB values) -[ ] make sure encoder generates no chunks with size > (2^31)-1 -[ ] partial decoding (stream processing) -[X] let the "isFullyOpaque" function check color keys and transparent palettes too -[X] better name for the variables "codes", "codesD", "codelengthcodes", "clcl" and "lldl" -[ ] don't stop decoding on errors like 69, 57, 58 (make warnings) -[ ] make option to choose if the raw image with non multiple of 8 bits per scanline should have padding bits or not -[ ] let the C++ wrapper catch exceptions coming from the standard library and return LodePNG error codes -*/ - -#endif /*LODEPNG_H inclusion guard*/ - -/* -LodePNG Documentation ---------------------- - -0. table of contents --------------------- - - 1. about - 1.1. supported features - 1.2. features not supported - 2. C and C++ version - 3. security - 4. decoding - 5. encoding - 6. color conversions - 6.1. PNG color types - 6.2. color conversions - 6.3. padding bits - 7. error values - 8. chunks and PNG editing - 9. compiler support - 10. examples - 10.1. decoder C++ example - 10.2. decoder C example - 11. changes - 12. contact information - - -1. about --------- - -PNG is a file format to store raster images losslessly with good compression, -supporting different color types and alpha channel. - -LodePNG is a PNG codec according to the Portable Network Graphics (PNG) -Specification (Second Edition) - W3C Recommendation 10 November 2003. - -The specifications used are: - -*) Portable Network Graphics (PNG) Specification (Second Edition): - http://www.w3.org/TR/2003/REC-PNG-20031110 -*) RFC 1950 ZLIB Compressed Data Format version 3.3: - http://www.gzip.org/zlib/rfc-zlib.html -*) RFC 1951 DEFLATE Compressed Data Format Specification ver 1.3: - http://www.gzip.org/zlib/rfc-deflate.html - -The most recent version of LodePNG can currently be found at -http://lodev.org/lodepng/ - -LodePNG works both in C (ISO C90) and C++, with a C++ wrapper that adds -extra functionality. - -LodePNG exists out of two files: --lodepng.h: the header file for both C and C++ --lodepng.c(pp): give it the name lodepng.c or lodepng.cpp (or .cc) depending on your usage - -If you want to start using LodePNG right away without reading this doc, get the -examples from the LodePNG website to see how to use it in code, or check the -smaller examples in chapter 13 here. - -LodePNG is simple but only supports the basic requirements. To achieve -simplicity, the following design choices were made: There are no dependencies -on any external library. There are functions to decode and encode a PNG with -a single function call, and extended versions of these functions taking a -LodePNGState struct allowing to specify or get more information. By default -the colors of the raw image are always RGB or RGBA, no matter what color type -the PNG file uses. To read and write files, there are simple functions to -convert the files to/from buffers in memory. - -This all makes LodePNG suitable for loading textures in games, demos and small -programs, ... It's less suitable for full fledged image editors, loading PNGs -over network (it requires all the image data to be available before decoding can -begin), life-critical systems, ... - -1.1. supported features ------------------------ - -The following features are supported by the decoder: - -*) decoding of PNGs with any color type, bit depth and interlace mode, to a 24- or 32-bit color raw image, - or the same color type as the PNG -*) encoding of PNGs, from any raw image to 24- or 32-bit color, or the same color type as the raw image -*) Adam7 interlace and deinterlace for any color type -*) loading the image from harddisk or decoding it from a buffer from other sources than harddisk -*) support for alpha channels, including RGBA color model, translucent palettes and color keying -*) zlib decompression (inflate) -*) zlib compression (deflate) -*) CRC32 and ADLER32 checksums -*) handling of unknown chunks, allowing making a PNG editor that stores custom and unknown chunks. -*) the following chunks are supported (generated/interpreted) by both encoder and decoder: - IHDR: header information - PLTE: color palette - IDAT: pixel data - IEND: the final chunk - tRNS: transparency for palettized images - tEXt: textual information - zTXt: compressed textual information - iTXt: international textual information - bKGD: suggested background color - pHYs: physical dimensions - tIME: modification time - -1.2. features not supported ---------------------------- - -The following features are _not_ supported: - -*) some features needed to make a conformant PNG-Editor might be still missing. -*) partial loading/stream processing. All data must be available and is processed in one call. -*) The following public chunks are not supported but treated as unknown chunks by LodePNG - cHRM, gAMA, iCCP, sRGB, sBIT, hIST, sPLT - Some of these are not supported on purpose: LodePNG wants to provide the RGB values - stored in the pixels, not values modified by system dependent gamma or color models. - - -2. C and C++ version --------------------- - -The C version uses buffers allocated with alloc that you need to free() -yourself. You need to use init and cleanup functions for each struct whenever -using a struct from the C version to avoid exploits and memory leaks. - -The C++ version has extra functions with std::vectors in the interface and the -lodepng::State class which is a LodePNGState with constructor and destructor. - -These files work without modification for both C and C++ compilers because all -the additional C++ code is in "#ifdef __cplusplus" blocks that make C-compilers -ignore it, and the C code is made to compile both with strict ISO C90 and C++. - -To use the C++ version, you need to rename the source file to lodepng.cpp -(instead of lodepng.c), and compile it with a C++ compiler. - -To use the C version, you need to rename the source file to lodepng.c (instead -of lodepng.cpp), and compile it with a C compiler. - - -3. Security ------------ - -Even if carefully designed, it's always possible that LodePNG contains possible -exploits. If you discover one, please let me know, and it will be fixed. - -When using LodePNG, care has to be taken with the C version of LodePNG, as well -as the C-style structs when working with C++. The following conventions are used -for all C-style structs: - --if a struct has a corresponding init function, always call the init function when making a new one --if a struct has a corresponding cleanup function, call it before the struct disappears to avoid memory leaks --if a struct has a corresponding copy function, use the copy function instead of "=". - The destination must also be inited already. - - -4. Decoding ------------ - -Decoding converts a PNG compressed image to a raw pixel buffer. - -Most documentation on using the decoder is at its declarations in the header -above. For C, simple decoding can be done with functions such as -lodepng_decode32, and more advanced decoding can be done with the struct -LodePNGState and lodepng_decode. For C++, all decoding can be done with the -various lodepng::decode functions, and lodepng::State can be used for advanced -features. - -When using the LodePNGState, it uses the following fields for decoding: -*) LodePNGInfo info_png: it stores extra information about the PNG (the input) in here -*) LodePNGColorMode info_raw: here you can say what color mode of the raw image (the output) you want to get -*) LodePNGDecoderSettings decoder: you can specify a few extra settings for the decoder to use - -LodePNGInfo info_png --------------------- - -After decoding, this contains extra information of the PNG image, except the actual -pixels, width and height because these are already gotten directly from the decoder -functions. - -It contains for example the original color type of the PNG image, text comments, -suggested background color, etc... More details about the LodePNGInfo struct are -at its declaration documentation. - -LodePNGColorMode info_raw -------------------------- - -When decoding, here you can specify which color type you want -the resulting raw image to be. If this is different from the colortype of the -PNG, then the decoder will automatically convert the result. This conversion -always works, except if you want it to convert a color PNG to greyscale or to -a palette with missing colors. - -By default, 32-bit color is used for the result. - -LodePNGDecoderSettings decoder ------------------------------- - -The settings can be used to ignore the errors created by invalid CRC and Adler32 -chunks, and to disable the decoding of tEXt chunks. - -There's also a setting color_convert, true by default. If false, no conversion -is done, the resulting data will be as it was in the PNG (after decompression) -and you'll have to puzzle the colors of the pixels together yourself using the -color type information in the LodePNGInfo. - - -5. Encoding ------------ - -Encoding converts a raw pixel buffer to a PNG compressed image. - -Most documentation on using the encoder is at its declarations in the header -above. For C, simple encoding can be done with functions such as -lodepng_encode32, and more advanced decoding can be done with the struct -LodePNGState and lodepng_encode. For C++, all encoding can be done with the -various lodepng::encode functions, and lodepng::State can be used for advanced -features. - -Like the decoder, the encoder can also give errors. However it gives less errors -since the encoder input is trusted, the decoder input (a PNG image that could -be forged by anyone) is not trusted. - -When using the LodePNGState, it uses the following fields for encoding: -*) LodePNGInfo info_png: here you specify how you want the PNG (the output) to be. -*) LodePNGColorMode info_raw: here you say what color type of the raw image (the input) has -*) LodePNGEncoderSettings encoder: you can specify a few settings for the encoder to use - -LodePNGInfo info_png --------------------- - -When encoding, you use this the opposite way as when decoding: for encoding, -you fill in the values you want the PNG to have before encoding. By default it's -not needed to specify a color type for the PNG since it's automatically chosen, -but it's possible to choose it yourself given the right settings. - -The encoder will not always exactly match the LodePNGInfo struct you give, -it tries as close as possible. Some things are ignored by the encoder. The -encoder uses, for example, the following settings from it when applicable: -colortype and bitdepth, text chunks, time chunk, the color key, the palette, the -background color, the interlace method, unknown chunks, ... - -When encoding to a PNG with colortype 3, the encoder will generate a PLTE chunk. -If the palette contains any colors for which the alpha channel is not 255 (so -there are translucent colors in the palette), it'll add a tRNS chunk. - -LodePNGColorMode info_raw -------------------------- - -You specify the color type of the raw image that you give to the input here, -including a possible transparent color key and palette you happen to be using in -your raw image data. - -By default, 32-bit color is assumed, meaning your input has to be in RGBA -format with 4 bytes (unsigned chars) per pixel. - -LodePNGEncoderSettings encoder ------------------------------- - -The following settings are supported (some are in sub-structs): -*) auto_convert: when this option is enabled, the encoder will -automatically choose the smallest possible color mode (including color key) that -can encode the colors of all pixels without information loss. -*) btype: the block type for LZ77. 0 = uncompressed, 1 = fixed huffman tree, - 2 = dynamic huffman tree (best compression). Should be 2 for proper - compression. -*) use_lz77: whether or not to use LZ77 for compressed block types. Should be - true for proper compression. -*) windowsize: the window size used by the LZ77 encoder (1 - 32768). Has value - 2048 by default, but can be set to 32768 for better, but slow, compression. -*) force_palette: if colortype is 2 or 6, you can make the encoder write a PLTE - chunk if force_palette is true. This can used as suggested palette to convert - to by viewers that don't support more than 256 colors (if those still exist) -*) add_id: add text chunk "Encoder: LodePNG " to the image. -*) text_compression: default 1. If 1, it'll store texts as zTXt instead of tEXt chunks. - zTXt chunks use zlib compression on the text. This gives a smaller result on - large texts but a larger result on small texts (such as a single program name). - It's all tEXt or all zTXt though, there's no separate setting per text yet. - - -6. color conversions --------------------- - -An important thing to note about LodePNG, is that the color type of the PNG, and -the color type of the raw image, are completely independent. By default, when -you decode a PNG, you get the result as a raw image in the color type you want, -no matter whether the PNG was encoded with a palette, greyscale or RGBA color. -And if you encode an image, by default LodePNG will automatically choose the PNG -color type that gives good compression based on the values of colors and amount -of colors in the image. It can be configured to let you control it instead as -well, though. - -To be able to do this, LodePNG does conversions from one color mode to another. -It can convert from almost any color type to any other color type, except the -following conversions: RGB to greyscale is not supported, and converting to a -palette when the palette doesn't have a required color is not supported. This is -not supported on purpose: this is information loss which requires a color -reduction algorithm that is beyong the scope of a PNG encoder (yes, RGB to grey -is easy, but there are multiple ways if you want to give some channels more -weight). - -By default, when decoding, you get the raw image in 32-bit RGBA or 24-bit RGB -color, no matter what color type the PNG has. And by default when encoding, -LodePNG automatically picks the best color model for the output PNG, and expects -the input image to be 32-bit RGBA or 24-bit RGB. So, unless you want to control -the color format of the images yourself, you can skip this chapter. - -6.1. PNG color types --------------------- - -A PNG image can have many color types, ranging from 1-bit color to 64-bit color, -as well as palettized color modes. After the zlib decompression and unfiltering -in the PNG image is done, the raw pixel data will have that color type and thus -a certain amount of bits per pixel. If you want the output raw image after -decoding to have another color type, a conversion is done by LodePNG. - -The PNG specification gives the following color types: - -0: greyscale, bit depths 1, 2, 4, 8, 16 -2: RGB, bit depths 8 and 16 -3: palette, bit depths 1, 2, 4 and 8 -4: greyscale with alpha, bit depths 8 and 16 -6: RGBA, bit depths 8 and 16 - -Bit depth is the amount of bits per pixel per color channel. So the total amount -of bits per pixel is: amount of channels * bitdepth. - -6.2. color conversions ----------------------- - -As explained in the sections about the encoder and decoder, you can specify -color types and bit depths in info_png and info_raw to change the default -behaviour. - -If, when decoding, you want the raw image to be something else than the default, -you need to set the color type and bit depth you want in the LodePNGColorMode, -or the parameters of the simple function of LodePNG you're using. - -If, when encoding, you use another color type than the default in the input -image, you need to specify its color type and bit depth in the LodePNGColorMode -of the raw image, or use the parameters of the simplefunction of LodePNG you're -using. - -If, when encoding, you don't want LodePNG to choose the output PNG color type -but control it yourself, you need to set auto_convert in the encoder settings -to LAC_NONE, and specify the color type you want in the LodePNGInfo of the -encoder. - -If you do any of the above, LodePNG may need to do a color conversion, which -follows the rules below, and may sometimes not be allowed. - -To avoid some confusion: --the decoder converts from PNG to raw image --the encoder converts from raw image to PNG --the colortype and bitdepth in LodePNGColorMode info_raw, are those of the raw image --the colortype and bitdepth in the color field of LodePNGInfo info_png, are those of the PNG --when encoding, the color type in LodePNGInfo is ignored if auto_convert - is enabled, it is automatically generated instead --when decoding, the color type in LodePNGInfo is set by the decoder to that of the original - PNG image, but it can be ignored since the raw image has the color type you requested instead --if the color type of the LodePNGColorMode and PNG image aren't the same, a conversion - between the color types is done if the color types are supported. If it is not - supported, an error is returned. If the types are the same, no conversion is done. --even though some conversions aren't supported, LodePNG supports loading PNGs from any - colortype and saving PNGs to any colortype, sometimes it just requires preparing - the raw image correctly before encoding. --both encoder and decoder use the same color converter. - -Non supported color conversions: --color to greyscale: no error is thrown, but the result will look ugly because -only the red channel is taken --anything, to palette when that palette does not have that color in it: in this -case an error is thrown - -Supported color conversions: --anything to 8-bit RGB, 8-bit RGBA, 16-bit RGB, 16-bit RGBA --any grey or grey+alpha, to grey or grey+alpha --anything to a palette, as long as the palette has the requested colors in it --removing alpha channel --higher to smaller bitdepth, and vice versa - -If you want no color conversion to be done: --In the encoder, you can make it save a PNG with any color type by giving the -raw color mode and LodePNGInfo the same color mode, and setting auto_convert to -LAC_NO. --In the decoder, you can make it store the pixel data in the same color type -as the PNG has, by setting the color_convert setting to false. Settings in -info_raw are then ignored. - -The function lodepng_convert does the color conversion. It is available in the -interface but normally isn't needed since the encoder and decoder already call -it. - -6.3. padding bits ------------------ - -In the PNG file format, if a less than 8-bit per pixel color type is used and the scanlines -have a bit amount that isn't a multiple of 8, then padding bits are used so that each -scanline starts at a fresh byte. But that is NOT true for the LodePNG raw input and output. -The raw input image you give to the encoder, and the raw output image you get from the decoder -will NOT have these padding bits, e.g. in the case of a 1-bit image with a width -of 7 pixels, the first pixel of the second scanline will the the 8th bit of the first byte, -not the first bit of a new byte. - - -7. error values ---------------- - -All functions in LodePNG that return an error code, return 0 if everything went -OK, or a non-zero code if there was an error. - -The meaning of the LodePNG error values can be retrieved with the function -lodepng_error_text: given the numerical error code, it returns a description -of the error in English as a string. - -Check the implementation of lodepng_error_text to see the meaning of each code. - - -8. chunks and PNG editing -------------------------- - -If you want to add extra chunks to a PNG you encode, or use LodePNG for a PNG -editor that should follow the rules about handling of unknown chunks, or if your -program is able to read other types of chunks than the ones handled by LodePNG, -then that's possible with the chunk functions of LodePNG. - -A PNG chunk has the following layout: - -4 bytes length -4 bytes type name -length bytes data -4 bytes CRC - -8.1. iterating through chunks ------------------------------ - -If you have a buffer containing the PNG image data, then the first chunk (the -IHDR chunk) starts at byte number 8 of that buffer. The first 8 bytes are the -signature of the PNG and are not part of a chunk. But if you start at byte 8 -then you have a chunk, and can check the following things of it. - -NOTE: none of these functions check for memory buffer boundaries. To avoid -exploits, always make sure the buffer contains all the data of the chunks. -When using lodepng_chunk_next, make sure the returned value is within the -allocated memory. - -unsigned lodepng_chunk_length(const unsigned char* chunk): - -Get the length of the chunk's data. The total chunk length is this length + 12. - -void lodepng_chunk_type(char type[5], const unsigned char* chunk): -unsigned char lodepng_chunk_type_equals(const unsigned char* chunk, const char* type): - -Get the type of the chunk or compare if it's a certain type - -unsigned char lodepng_chunk_critical(const unsigned char* chunk): -unsigned char lodepng_chunk_private(const unsigned char* chunk): -unsigned char lodepng_chunk_safetocopy(const unsigned char* chunk): - -Check if the chunk is critical in the PNG standard (only IHDR, PLTE, IDAT and IEND are). -Check if the chunk is private (public chunks are part of the standard, private ones not). -Check if the chunk is safe to copy. If it's not, then, when modifying data in a critical -chunk, unsafe to copy chunks of the old image may NOT be saved in the new one if your -program doesn't handle that type of unknown chunk. - -unsigned char* lodepng_chunk_data(unsigned char* chunk): -const unsigned char* lodepng_chunk_data_const(const unsigned char* chunk): - -Get a pointer to the start of the data of the chunk. - -unsigned lodepng_chunk_check_crc(const unsigned char* chunk): -void lodepng_chunk_generate_crc(unsigned char* chunk): - -Check if the crc is correct or generate a correct one. - -unsigned char* lodepng_chunk_next(unsigned char* chunk): -const unsigned char* lodepng_chunk_next_const(const unsigned char* chunk): - -Iterate to the next chunk. This works if you have a buffer with consecutive chunks. Note that these -functions do no boundary checking of the allocated data whatsoever, so make sure there is enough -data available in the buffer to be able to go to the next chunk. - -unsigned lodepng_chunk_append(unsigned char** out, size_t* outlength, const unsigned char* chunk): -unsigned lodepng_chunk_create(unsigned char** out, size_t* outlength, unsigned length, - const char* type, const unsigned char* data): - -These functions are used to create new chunks that are appended to the data in *out that has -length *outlength. The append function appends an existing chunk to the new data. The create -function creates a new chunk with the given parameters and appends it. Type is the 4-letter -name of the chunk. - -8.2. chunks in info_png ------------------------ - -The LodePNGInfo struct contains fields with the unknown chunk in it. It has 3 -buffers (each with size) to contain 3 types of unknown chunks: -the ones that come before the PLTE chunk, the ones that come between the PLTE -and the IDAT chunks, and the ones that come after the IDAT chunks. -It's necessary to make the distionction between these 3 cases because the PNG -standard forces to keep the ordering of unknown chunks compared to the critical -chunks, but does not force any other ordering rules. - -info_png.unknown_chunks_data[0] is the chunks before PLTE -info_png.unknown_chunks_data[1] is the chunks after PLTE, before IDAT -info_png.unknown_chunks_data[2] is the chunks after IDAT - -The chunks in these 3 buffers can be iterated through and read by using the same -way described in the previous subchapter. - -When using the decoder to decode a PNG, you can make it store all unknown chunks -if you set the option settings.remember_unknown_chunks to 1. By default, this -option is off (0). - -The encoder will always encode unknown chunks that are stored in the info_png. -If you need it to add a particular chunk that isn't known by LodePNG, you can -use lodepng_chunk_append or lodepng_chunk_create to the chunk data in -info_png.unknown_chunks_data[x]. - -Chunks that are known by LodePNG should not be added in that way. E.g. to make -LodePNG add a bKGD chunk, set background_defined to true and add the correct -parameters there instead. - - -9. compiler support -------------------- - -No libraries other than the current standard C library are needed to compile -LodePNG. For the C++ version, only the standard C++ library is needed on top. -Add the files lodepng.c(pp) and lodepng.h to your project, include -lodepng.h where needed, and your program can read/write PNG files. - -If performance is important, use optimization when compiling! For both the -encoder and decoder, this makes a large difference. - -Make sure that LodePNG is compiled with the same compiler of the same version -and with the same settings as the rest of the program, or the interfaces with -std::vectors and std::strings in C++ can be incompatible. - -CHAR_BITS must be 8 or higher, because LodePNG uses unsigned chars for octets. - -*) gcc and g++ - -LodePNG is developed in gcc so this compiler is natively supported. It gives no -warnings with compiler options "-Wall -Wextra -pedantic -ansi", with gcc and g++ -version 4.7.0 on Linux. - -*) Mingw - -The Mingw compiler (a port of gcc) for Windows is fully supported by LodePNG. - -*) Visual Studio 2005 and Visual C++ 2005 Express Edition - -Versions 20070604 up to 20080107 have been tested on VS2005 and work. Visual -studio may give warnings about 'fopen' being deprecated. A multiplatform library -can't support the proposed Visual Studio alternative however. - -If you're using LodePNG in VS2005 and don't want to see the deprecated warnings, -put this on top of lodepng.h before the inclusions: -#define _CRT_SECURE_NO_DEPRECATE - -Visual Studio may want "stdafx.h" files to be included in each source file. That -is not standard C++ and will not be added to the stock LodePNG. Try to find a -setting to disable it for this source file. - -*) Visual Studio 6.0 - -LodePNG support for Visual Studio 6.0 is not guaranteed because VS6 doesn't -follow the C++ standard correctly. - -*) Comeau C/C++ - -Vesion 20070107 compiles without problems on the Comeau C/C++ Online Test Drive -at http://www.comeaucomputing.com/tryitout in both C90 and C++ mode. - -*) Compilers on Macintosh - -LodePNG has been reported to work both with the gcc and LLVM for Macintosh, both -for C and C++. - -*) Other Compilers - -If you encounter problems on other compilers, feel free to let me know and I may -try to fix it if the compiler is modern standards complient. - - -10. examples ------------- - -This decoder example shows the most basic usage of LodePNG. More complex -examples can be found on the LodePNG website. - -10.1. decoder C++ example -------------------------- - -#include "lodepng.h" -#include - -int main(int argc, char *argv[]) -{ - const char* filename = argc > 1 ? argv[1] : "test.png"; - - //load and decode - std::vector image; - unsigned width, height; - unsigned error = lodepng::decode(image, width, height, filename); - - //if there's an error, display it - if(error) std::cout << "decoder error " << error << ": " << lodepng_error_text(error) << std::endl; - - //the pixels are now in the vector "image", 4 bytes per pixel, ordered RGBARGBA..., use it as texture, draw it, ... -} - -10.2. decoder C example ------------------------ - -#include "lodepng.h" - -int main(int argc, char *argv[]) -{ - unsigned error; - unsigned char* image; - size_t width, height; - const char* filename = argc > 1 ? argv[1] : "test.png"; - - error = lodepng_decode32_file(&image, &width, &height, filename); - - if(error) printf("decoder error %u: %s\n", error, lodepng_error_text(error)); - - / * use image here * / - - free(image); - return 0; -} - - -11. changes ------------ - -The version number of LodePNG is the date of the change given in the format -yyyymmdd. - -Some changes aren't backwards compatible. Those are indicated with a (!) -symbol. - -*) 23 jun 2012: Added more filter strategies. Made it easier to use custom alloc - and free functions and toggle #defines from compiler flags. Small fixes. -*) 6 may 2012 (!): Made plugging in custom zlib/deflate functions more flexible. -*) 22 apr 2012 (!): Made interface more consistent, renaming a lot. Removed - redundant C++ codec classes. Reduced amount of structs. Everything changed, - but it is cleaner now imho and functionality remains the same. Also fixed - several bugs and shrinked the implementation code. Made new samples. -*) 6 nov 2011 (!): By default, the encoder now automatically chooses the best - PNG color model and bit depth, based on the amount and type of colors of the - raw image. For this, autoLeaveOutAlphaChannel replaced by auto_choose_color. -*) 9 okt 2011: simpler hash chain implementation for the encoder. -*) 8 sep 2011: lz77 encoder lazy matching instead of greedy matching. -*) 23 aug 2011: tweaked the zlib compression parameters after benchmarking. - A bug with the PNG filtertype heuristic was fixed, so that it chooses much - better ones (it's quite significant). A setting to do an experimental, slow, - brute force search for PNG filter types is added. -*) 17 aug 2011 (!): changed some C zlib related function names. -*) 16 aug 2011: made the code less wide (max 120 characters per line). -*) 17 apr 2011: code cleanup. Bugfixes. Convert low to 16-bit per sample colors. -*) 21 feb 2011: fixed compiling for C90. Fixed compiling with sections disabled. -*) 11 dec 2010: encoding is made faster, based on suggestion by Peter Eastman - to optimize long sequences of zeros. -*) 13 nov 2010: added LodePNG_InfoColor_hasPaletteAlpha and - LodePNG_InfoColor_canHaveAlpha functions for convenience. -*) 7 nov 2010: added LodePNG_error_text function to get error code description. -*) 30 okt 2010: made decoding slightly faster -*) 26 okt 2010: (!) changed some C function and struct names (more consistent). - Reorganized the documentation and the declaration order in the header. -*) 08 aug 2010: only changed some comments and external samples. -*) 05 jul 2010: fixed bug thanks to warnings in the new gcc version. -*) 14 mar 2010: fixed bug where too much memory was allocated for char buffers. -*) 02 sep 2008: fixed bug where it could create empty tree that linux apps could - read by ignoring the problem but windows apps couldn't. -*) 06 jun 2008: added more error checks for out of memory cases. -*) 26 apr 2008: added a few more checks here and there to ensure more safety. -*) 06 mar 2008: crash with encoding of strings fixed -*) 02 feb 2008: support for international text chunks added (iTXt) -*) 23 jan 2008: small cleanups, and #defines to divide code in sections -*) 20 jan 2008: support for unknown chunks allowing using LodePNG for an editor. -*) 18 jan 2008: support for tIME and pHYs chunks added to encoder and decoder. -*) 17 jan 2008: ability to encode and decode compressed zTXt chunks added - Also vareous fixes, such as in the deflate and the padding bits code. -*) 13 jan 2008: Added ability to encode Adam7-interlaced images. Improved - filtering code of encoder. -*) 07 jan 2008: (!) changed LodePNG to use ISO C90 instead of C++. A - C++ wrapper around this provides an interface almost identical to before. - Having LodePNG be pure ISO C90 makes it more portable. The C and C++ code - are together in these files but it works both for C and C++ compilers. -*) 29 dec 2007: (!) changed most integer types to unsigned int + other tweaks -*) 30 aug 2007: bug fixed which makes this Borland C++ compatible -*) 09 aug 2007: some VS2005 warnings removed again -*) 21 jul 2007: deflate code placed in new namespace separate from zlib code -*) 08 jun 2007: fixed bug with 2- and 4-bit color, and small interlaced images -*) 04 jun 2007: improved support for Visual Studio 2005: crash with accessing - invalid std::vector element [0] fixed, and level 3 and 4 warnings removed -*) 02 jun 2007: made the encoder add a tag with version by default -*) 27 may 2007: zlib and png code separated (but still in the same file), - simple encoder/decoder functions added for more simple usage cases -*) 19 may 2007: minor fixes, some code cleaning, new error added (error 69), - moved some examples from here to lodepng_examples.cpp -*) 12 may 2007: palette decoding bug fixed -*) 24 apr 2007: changed the license from BSD to the zlib license -*) 11 mar 2007: very simple addition: ability to encode bKGD chunks. -*) 04 mar 2007: (!) tEXt chunk related fixes, and support for encoding - palettized PNG images. Plus little interface change with palette and texts. -*) 03 mar 2007: Made it encode dynamic Huffman shorter with repeat codes. - Fixed a bug where the end code of a block had length 0 in the Huffman tree. -*) 26 feb 2007: Huffman compression with dynamic trees (BTYPE 2) now implemented - and supported by the encoder, resulting in smaller PNGs at the output. -*) 27 jan 2007: Made the Adler-32 test faster so that a timewaste is gone. -*) 24 jan 2007: gave encoder an error interface. Added color conversion from any - greyscale type to 8-bit greyscale with or without alpha. -*) 21 jan 2007: (!) Totally changed the interface. It allows more color types - to convert to and is more uniform. See the manual for how it works now. -*) 07 jan 2007: Some cleanup & fixes, and a few changes over the last days: - encode/decode custom tEXt chunks, separate classes for zlib & deflate, and - at last made the decoder give errors for incorrect Adler32 or Crc. -*) 01 jan 2007: Fixed bug with encoding PNGs with less than 8 bits per channel. -*) 29 dec 2006: Added support for encoding images without alpha channel, and - cleaned out code as well as making certain parts faster. -*) 28 dec 2006: Added "Settings" to the encoder. -*) 26 dec 2006: The encoder now does LZ77 encoding and produces much smaller files now. - Removed some code duplication in the decoder. Fixed little bug in an example. -*) 09 dec 2006: (!) Placed output parameters of public functions as first parameter. - Fixed a bug of the decoder with 16-bit per color. -*) 15 okt 2006: Changed documentation structure -*) 09 okt 2006: Encoder class added. It encodes a valid PNG image from the - given image buffer, however for now it's not compressed. -*) 08 sep 2006: (!) Changed to interface with a Decoder class -*) 30 jul 2006: (!) LodePNG_InfoPng , width and height are now retrieved in different - way. Renamed decodePNG to decodePNGGeneric. -*) 29 jul 2006: (!) Changed the interface: image info is now returned as a - struct of type LodePNG::LodePNG_Info, instead of a vector, which was a bit clumsy. -*) 28 jul 2006: Cleaned the code and added new error checks. - Corrected terminology "deflate" into "inflate". -*) 23 jun 2006: Added SDL example in the documentation in the header, this - example allows easy debugging by displaying the PNG and its transparency. -*) 22 jun 2006: (!) Changed way to obtain error value. Added - loadFile function for convenience. Made decodePNG32 faster. -*) 21 jun 2006: (!) Changed type of info vector to unsigned. - Changed position of palette in info vector. Fixed an important bug that - happened on PNGs with an uncompressed block. -*) 16 jun 2006: Internally changed unsigned into unsigned where - needed, and performed some optimizations. -*) 07 jun 2006: (!) Renamed functions to decodePNG and placed them - in LodePNG namespace. Changed the order of the parameters. Rewrote the - documentation in the header. Renamed files to lodepng.cpp and lodepng.h -*) 22 apr 2006: Optimized and improved some code -*) 07 sep 2005: (!) Changed to std::vector interface -*) 12 aug 2005: Initial release (C++, decoder only) - - -12. contact information ------------------------ - -Feel free to contact me with suggestions, problems, comments, ... concerning -LodePNG. If you encounter a PNG image that doesn't work properly with this -decoder, feel free to send it and I'll use it to find and fix the problem. - -My email address is (puzzle the account and domain together with an @ symbol): -Domain: gmail dot com. -Account: lode dot vandevenne. - - -Copyright (c) 2005-2012 Lode Vandevenne -*/ diff --git a/lib/picopng.c b/lib/picopng.c deleted file mode 100644 index 77cd81c..0000000 --- a/lib/picopng.c +++ /dev/null @@ -1,810 +0,0 @@ -// picoPNG version 20080503 (cleaned up and ported to c by kaitek) -// Copyright (c) 2005-2008 Lode Vandevenne -// -// This software is provided 'as-is', without any express or implied -// warranty. In no event will the authors be held liable for any damages -// arising from the use of this software. -// -// Permission is granted to anyone to use this software for any purpose, -// including commercial applications, and to alter it and redistribute it -// freely, subject to the following restrictions: -// -// 1. The origin of this software must not be misrepresented; you must not -// claim that you wrote the original software. If you use this software -// in a product, an acknowledgment in the product documentation would be -// appreciated but is not required. -// 2. Altered source versions must be plainly marked as such, and must not be -// misrepresented as being the original software. -// 3. This notice may not be removed or altered from any source distribution. - -#include -#include -#include "picopng.h" - -/*************************************************************************************************/ - -typedef struct png_alloc_node { - struct png_alloc_node *prev, *next; - void *addr; - size_t size; -} png_alloc_node_t; - -png_alloc_node_t *png_alloc_head = NULL; -png_alloc_node_t *png_alloc_tail = NULL; - -png_alloc_node_t *png_alloc_find_node(void *addr) -{ - png_alloc_node_t *node; - for (node = png_alloc_head; node; node = node->next) - if (node->addr == addr) - break; - return node; -} - -void png_alloc_add_node(void *addr, size_t size) -{ - png_alloc_node_t *node; - if (png_alloc_find_node(addr)) - return; - node = malloc(sizeof (png_alloc_node_t)); - node->addr = addr; - node->size = size; - node->prev = png_alloc_tail; - node->next = NULL; - png_alloc_tail = node; - if (node->prev) - node->prev->next = node; - if (!png_alloc_head) - png_alloc_head = node; -} - -void png_alloc_remove_node(png_alloc_node_t *node) -{ - if (node->prev) - node->prev->next = node->next; - if (node->next) - node->next->prev = node->prev; - if (node == png_alloc_head) - png_alloc_head = node->next; - if (node == png_alloc_tail) - png_alloc_tail = node->prev; - node->prev = node->next = node->addr = NULL; - free(node); -} - -void *png_alloc_malloc(size_t size) -{ - void *addr = malloc(size); - png_alloc_add_node(addr, size); - return addr; -} - -void *png_alloc_realloc(void *addr, size_t size) -{ - void *new_addr; - if (!addr) - return png_alloc_malloc(size); - new_addr = realloc(addr, size); - if (new_addr != addr) { - png_alloc_node_t *old_node; - old_node = png_alloc_find_node(addr); - png_alloc_remove_node(old_node); - png_alloc_add_node(new_addr, size); - } - return new_addr; -} - -void png_alloc_free(void *addr) -{ - png_alloc_node_t *node = png_alloc_find_node(addr); - if (!node) - return; - png_alloc_remove_node(node); - free(addr); -} - -void png_alloc_free_all() -{ - while (png_alloc_tail) { - void *addr = png_alloc_tail->addr; - png_alloc_remove_node(png_alloc_tail); - free(addr); - } -} - -/*************************************************************************************************/ - -__maybe_unused void vector32_cleanup(vector32_t *p) -{ - p->size = p->allocsize = 0; - if (p->data) - png_alloc_free(p->data); - p->data = NULL; -} - -uint32_t vector32_resize(vector32_t *p, size_t size) -{ // returns 1 if success, 0 if failure ==> nothing done - if (size * sizeof (uint32_t) > p->allocsize) { - size_t newsize = size * sizeof (uint32_t) * 2; - void *data = png_alloc_realloc(p->data, newsize); - if (data) { - p->allocsize = newsize; - p->data = (uint32_t *) data; - p->size = size; - } else - return 0; - } else - p->size = size; - return 1; -} - -uint32_t vector32_resizev(vector32_t *p, size_t size, uint32_t value) -{ // resize and give all new elements the value - size_t oldsize = p->size, i; - if (!vector32_resize(p, size)) - return 0; - for (i = oldsize; i < size; i++) - p->data[i] = value; - return 1; -} - -void vector32_init(vector32_t *p) -{ - p->data = NULL; - p->size = p->allocsize = 0; -} - -vector32_t *vector32_new(size_t size, uint32_t value) -{ - vector32_t *p = png_alloc_malloc(sizeof (vector32_t)); - vector32_init(p); - if (size && !vector32_resizev(p, size, value)) - return NULL; - return p; -} - -/*************************************************************************************************/ - -__maybe_unused void vector8_cleanup(vector8_t *p) -{ - p->size = p->allocsize = 0; - if (p->data) - png_alloc_free(p->data); - p->data = NULL; -} - -uint32_t vector8_resize(vector8_t *p, size_t size) -{ // returns 1 if success, 0 if failure ==> nothing done - // xxx: the use of sizeof uint32_t here seems like a bug (this descends from the lodepng vector - // compatibility functions which do the same). without this there is corruption in certain cases, - // so this was probably done to cover up allocation bug(s) in the original picopng code! - if (size * sizeof (uint32_t) > p->allocsize) { - size_t newsize = size * sizeof (uint32_t) * 2; - void *data = png_alloc_realloc(p->data, newsize); - if (data) { - p->allocsize = newsize; - p->data = (uint8_t *) data; - p->size = size; - } else - return 0; // error: not enough memory - } else - p->size = size; - return 1; -} - -uint32_t vector8_resizev(vector8_t *p, size_t size, uint8_t value) -{ // resize and give all new elements the value - size_t oldsize = p->size, i; - if (!vector8_resize(p, size)) - return 0; - for (i = oldsize; i < size; i++) - p->data[i] = value; - return 1; -} - -void vector8_init(vector8_t *p) -{ - p->data = NULL; - p->size = p->allocsize = 0; -} - -vector8_t *vector8_new(size_t size, uint8_t value) -{ - vector8_t *p = png_alloc_malloc(sizeof (vector8_t)); - vector8_init(p); - if (size && !vector8_resizev(p, size, value)) - return NULL; - return p; -} - -vector8_t *vector8_copy(vector8_t *p) -{ - vector8_t *q = vector8_new(p->size, 0); - uint32_t n; - for (n = 0; n < q->size; n++) - q->data[n] = p->data[n]; - return q; -} - -/*************************************************************************************************/ -int Zlib_decompress(vector8_t *out, const vector8_t *in) // returns error value -{ - return picopng_zlib_decompress(out->data, out->size, in->data, in->size); -} - -/*************************************************************************************************/ - -#define PNG_SIGNATURE 0x0a1a0a0d474e5089ull - -#define CHUNK_IHDR 0x52444849 -#define CHUNK_IDAT 0x54414449 -#define CHUNK_IEND 0x444e4549 -#define CHUNK_PLTE 0x45544c50 -#define CHUNK_tRNS 0x534e5274 - -int PNG_error; - -uint32_t PNG_readBitFromReversedStream(size_t *bitp, const uint8_t *bits) -{ - uint32_t result = (bits[*bitp >> 3] >> (7 - (*bitp & 0x7))) & 1; - (*bitp)++; - return result; -} - -uint32_t PNG_readBitsFromReversedStream(size_t *bitp, const uint8_t *bits, uint32_t nbits) -{ - uint32_t i, result = 0; - for (i = nbits - 1; i < nbits; i--) - result += ((PNG_readBitFromReversedStream(bitp, bits)) << i); - return result; -} - -void PNG_setBitOfReversedStream(size_t *bitp, uint8_t *bits, uint32_t bit) -{ - bits[*bitp >> 3] |= (bit << (7 - (*bitp & 0x7))); - (*bitp)++; -} - -uint32_t PNG_read32bitInt(const uint8_t *buffer) -{ - return (buffer[0] << 24) | (buffer[1] << 16) | (buffer[2] << 8) | buffer[3]; -} - -int PNG_checkColorValidity(uint32_t colorType, uint32_t bd) // return type is a LodePNG error code -{ - if ((colorType == 2 || colorType == 4 || colorType == 6)) { - if (!(bd == 8 || bd == 16)) - return 37; - else - return 0; - } else if (colorType == 0) { - if (!(bd == 1 || bd == 2 || bd == 4 || bd == 8 || bd == 16)) - return 37; - else - return 0; - } else if (colorType == 3) { - if (!(bd == 1 || bd == 2 || bd == 4 || bd == 8)) - return 37; - else - return 0; - } else - return 31; // nonexistent color type -} - -uint32_t PNG_getBpp(const PNG_info_t *info) -{ - uint32_t bitDepth, colorType; - bitDepth = info->bitDepth; - colorType = info->colorType; - if (colorType == 2) - return (3 * bitDepth); - else if (colorType >= 4) - return (colorType - 2) * bitDepth; - else - return bitDepth; -} - -void PNG_readPngHeader(PNG_info_t *info, const uint8_t *in, size_t inlength) -{ // read the information from the header and store it in the Info - if (inlength < 29) { - PNG_error = 27; // error: the data length is smaller than the length of the header - return; - } - if (*(uint64_t *) in != PNG_SIGNATURE) { - PNG_error = 28; // no PNG signature - return; - } - if (*(uint32_t *) &in[12] != CHUNK_IHDR) { - PNG_error = 29; // error: it doesn't start with a IHDR chunk! - return; - } - info->width = PNG_read32bitInt(&in[16]); - info->height = PNG_read32bitInt(&in[20]); - info->bitDepth = in[24]; - info->colorType = in[25]; - info->compressionMethod = in[26]; - if (in[26] != 0) { - PNG_error = 32; // error: only compression method 0 is allowed in the specification - return; - } - info->filterMethod = in[27]; - if (in[27] != 0) { - PNG_error = 33; // error: only filter method 0 is allowed in the specification - return; - } - info->interlaceMethod = in[28]; - if (in[28] > 1) { - PNG_error = 34; // error: only interlace methods 0 and 1 exist in the specification - return; - } - PNG_error = PNG_checkColorValidity(info->colorType, info->bitDepth); -} - -int PNG_paethPredictor(int a, int b, int c) // Paeth predicter, used by PNG filter type 4 -{ - int p, pa, pb, pc; - p = a + b - c; - pa = p > a ? (p - a) : (a - p); - pb = p > b ? (p - b) : (b - p); - pc = p > c ? (p - c) : (c - p); - return (pa <= pb && pa <= pc) ? a : (pb <= pc ? b : c); -} - -void PNG_unFilterScanline(uint8_t *recon, const uint8_t *scanline, const uint8_t *precon, - size_t bytewidth, uint32_t filterType, size_t length) -{ - size_t i; - switch (filterType) { - case 0: - for (i = 0; i < length; i++) - recon[i] = scanline[i]; - break; - case 1: - for (i = 0; i < bytewidth; i++) - recon[i] = scanline[i]; - for (i = bytewidth; i < length; i++) - recon[i] = scanline[i] + recon[i - bytewidth]; - break; - case 2: - if (precon) - for (i = 0; i < length; i++) - recon[i] = scanline[i] + precon[i]; - else - for (i = 0; i < length; i++) - recon[i] = scanline[i]; - break; - case 3: - if (precon) { - for (i = 0; i < bytewidth; i++) - recon[i] = scanline[i] + precon[i] / 2; - for (i = bytewidth; i < length; i++) - recon[i] = scanline[i] + ((recon[i - bytewidth] + precon[i]) / 2); - } else { - for (i = 0; i < bytewidth; i++) - recon[i] = scanline[i]; - for (i = bytewidth; i < length; i++) - recon[i] = scanline[i] + recon[i - bytewidth] / 2; - } - break; - case 4: - if (precon) { - for (i = 0; i < bytewidth; i++) - recon[i] = (uint8_t) (scanline[i] + PNG_paethPredictor(0, precon[i], 0)); - for (i = bytewidth; i < length; i++) - recon[i] = (uint8_t) (scanline[i] + PNG_paethPredictor(recon[i - bytewidth], - precon[i], precon[i - bytewidth])); - } else { - for (i = 0; i < bytewidth; i++) - recon[i] = scanline[i]; - for (i = bytewidth; i < length; i++) - recon[i] = (uint8_t) (scanline[i] + PNG_paethPredictor(recon[i - bytewidth], 0, 0)); - } - break; - default: - PNG_error = 36; // error: nonexistent filter type given - return; - } -} - -void PNG_adam7Pass(uint8_t *out, uint8_t *linen, uint8_t *lineo, const uint8_t *in, uint32_t w, - size_t passleft, size_t passtop, size_t spacex, size_t spacey, size_t passw, size_t passh, - uint32_t bpp) -{ - size_t bytewidth, linelength; - uint32_t y; - uint8_t *temp; - // filter and reposition the pixels into the output when the image is Adam7 interlaced. This - // function can only do it after the full image is already decoded. The out buffer must have - // the correct allocated memory size already. - if (passw == 0) - return; - bytewidth = (bpp + 7) / 8; - linelength = 1 + ((bpp * passw + 7) / 8); - for (y = 0; y < passh; y++) { - size_t i, b; - uint8_t filterType = in[y * linelength], *prevline = (y == 0) ? 0 : lineo; - PNG_unFilterScanline(linen, &in[y * linelength + 1], prevline, bytewidth, filterType, - (w * bpp + 7) / 8); - if (PNG_error) - return; - if (bpp >= 8) - for (i = 0; i < passw; i++) - for (b = 0; b < bytewidth; b++) // b = current byte of this pixel - out[bytewidth * w * (passtop + spacey * y) + bytewidth * - (passleft + spacex * i) + b] = linen[bytewidth * i + b]; - else - for (i = 0; i < passw; i++) { - size_t obp, bp; - obp = bpp * w * (passtop + spacey * y) + bpp * (passleft + spacex * i); - bp = i * bpp; - for (b = 0; b < bpp; b++) - PNG_setBitOfReversedStream(&obp, out, PNG_readBitFromReversedStream(&bp, linen)); - } - temp = linen; - linen = lineo; - lineo = temp; // swap the two buffer pointers "line old" and "line new" - } -} - -int PNG_convert(const PNG_info_t *info, vector8_t *out, const uint8_t *in) -{ // converts from any color type to 32-bit. return value = LodePNG error code - size_t i, c; - uint32_t bitDepth, colorType; - size_t numpixels, bp; - uint8_t *out_data; - - bitDepth = info->bitDepth; - colorType = info->colorType; - numpixels = info->width * info->height; - bp = 0; - vector8_resize(out, numpixels * 4); - out_data = out->size ? out->data : 0; - if (bitDepth == 8 && colorType == 0) // greyscale - for (i = 0; i < numpixels; i++) { - out_data[4 * i + 0] = out_data[4 * i + 1] = out_data[4 * i + 2] = in[i]; - out_data[4 * i + 3] = (info->key_defined && (in[i] == info->key_r)) ? 0 : 255; - } - else if (bitDepth == 8 && colorType == 2) // RGB color - for (i = 0; i < numpixels; i++) { - for (c = 0; c < 3; c++) - out_data[4 * i + c] = in[3 * i + c]; - out_data[4 * i + 3] = (info->key_defined && (in[3 * i + 0] == info->key_r) && - (in[3 * i + 1] == info->key_g) && (in[3 * i + 2] == info->key_b)) ? 0 : 255; - } - else if (bitDepth == 8 && colorType == 3) // indexed color (palette) - for (i = 0; i < numpixels; i++) { - if (4U * in[i] >= info->palette->size) - return 46; - for (c = 0; c < 4; c++) // get rgb colors from the palette - out_data[4 * i + c] = info->palette->data[4 * in[i] + c]; - } - else if (bitDepth == 8 && colorType == 4) // greyscale with alpha - for (i = 0; i < numpixels; i++) { - out_data[4 * i + 0] = out_data[4 * i + 1] = out_data[4 * i + 2] = in[2 * i + 0]; - out_data[4 * i + 3] = in[2 * i + 1]; - } - else if (bitDepth == 8 && colorType == 6) - for (i = 0; i < numpixels; i++) - for (c = 0; c < 4; c++) - out_data[4 * i + c] = in[4 * i + c]; // RGB with alpha - else if (bitDepth == 16 && colorType == 0) // greyscale - for (i = 0; i < numpixels; i++) { - out_data[4 * i + 0] = out_data[4 * i + 1] = out_data[4 * i + 2] = in[2 * i]; - out_data[4 * i + 3] = (info->key_defined && (256U * in[i] + in[i + 1] == info->key_r)) - ? 0 : 255; - } - else if (bitDepth == 16 && colorType == 2) // RGB color - for (i = 0; i < numpixels; i++) { - for (c = 0; c < 3; c++) - out_data[4 * i + c] = in[6 * i + 2 * c]; - out_data[4 * i + 3] = (info->key_defined && - (256U * in[6 * i + 0] + in[6 * i + 1] == info->key_r) && - (256U * in[6 * i + 2] + in[6 * i + 3] == info->key_g) && - (256U * in[6 * i + 4] + in[6 * i + 5] == info->key_b)) ? 0 : 255; - } - else if (bitDepth == 16 && colorType == 4) // greyscale with alpha - for (i = 0; i < numpixels; i++) { - out_data[4 * i + 0] = out_data[4 * i + 1] = out_data[4 * i + 2] = in[4 * i]; // msb - out_data[4 * i + 3] = in[4 * i + 2]; - } - else if (bitDepth == 16 && colorType == 6) - for (i = 0; i < numpixels; i++) - for (c = 0; c < 4; c++) - out_data[4 * i + c] = in[8 * i + 2 * c]; // RGB with alpha - else if (bitDepth < 8 && colorType == 0) // greyscale - for (i = 0; i < numpixels; i++) { - uint32_t value = (PNG_readBitsFromReversedStream(&bp, in, bitDepth) * 255) / - ((1 << bitDepth) - 1); // scale value from 0 to 255 - out_data[4 * i + 0] = out_data[4 * i + 1] = out_data[4 * i + 2] = (uint8_t) value; - out_data[4 * i + 3] = (info->key_defined && value && - (((1U << bitDepth) - 1U) == info->key_r) && ((1U << bitDepth) - 1U)) ? 0 : 255; - } - else if (bitDepth < 8 && colorType == 3) // palette - for (i = 0; i < numpixels; i++) { - uint32_t value = PNG_readBitsFromReversedStream(&bp, in, bitDepth); - if (4 * value >= info->palette->size) - return 47; - for (c = 0; c < 4; c++) // get rgb colors from the palette - out_data[4 * i + c] = info->palette->data[4 * value + c]; - } - return 0; -} - -PNG_info_t *PNG_info_new(void) -{ - PNG_info_t *info = png_alloc_malloc(sizeof (PNG_info_t)); - uint32_t i; - for (i = 0; i < sizeof (PNG_info_t); i++) - ((uint8_t *) info)[i] = 0; - info->palette = vector8_new(0, 0); - info->image = vector8_new(0, 0); - return info; -} - -PNG_info_t *PNG_decode(const uint8_t *in, uint32_t size) -{ - PNG_info_t *info; - size_t pos; - vector8_t *idat; - bool IEND, known_type; - uint32_t bpp; - vector8_t *scanlines; // now the out buffer will be filled - size_t bytewidth, outlength; - uint8_t *out_data; - - PNG_error = 0; - - if (size == 0 || in == 0) { - PNG_error = 48; // the given data is empty - return NULL; - } - info = PNG_info_new(); - PNG_readPngHeader(info, in, size); - if (PNG_error) - return NULL; - pos = 33; // first byte of the first chunk after the header - idat = NULL; // the data from idat chunks - IEND = false; - known_type = true; - info->key_defined = false; - // loop through the chunks, ignoring unknown chunks and stopping at IEND chunk. IDAT data is - // put at the start of the in buffer - while (!IEND) { - size_t i, j; - size_t chunkLength; - uint32_t chunkType; - - if (pos + 8 >= size) { - PNG_error = 30; // error: size of the in buffer too small to contain next chunk - return NULL; - } - chunkLength = PNG_read32bitInt(&in[pos]); - pos += 4; - if (chunkLength > 0x7fffffff) { - PNG_error = 63; - return NULL; - } - if (pos + chunkLength >= size) { - PNG_error = 35; // error: size of the in buffer too small to contain next chunk - return NULL; - } - chunkType = *(uint32_t *) &in[pos]; - if (chunkType == CHUNK_IDAT) { // IDAT: compressed image data chunk - size_t offset = 0; - if (idat) { - offset = idat->size; - vector8_resize(idat, offset + chunkLength); - } else - idat = vector8_new(chunkLength, 0); - for (i = 0; i < chunkLength; i++) - idat->data[offset + i] = in[pos + 4 + i]; - pos += (4 + chunkLength); - } else if (chunkType == CHUNK_IEND) { // IEND - pos += 4; - IEND = true; - } else if (chunkType == CHUNK_PLTE) { // PLTE: palette chunk - pos += 4; // go after the 4 letters - vector8_resize(info->palette, 4 * (chunkLength / 3)); - if (info->palette->size > (4 * 256)) { - PNG_error = 38; // error: palette too big - return NULL; - } - for (i = 0; i < info->palette->size; i += 4) { - for (j = 0; j < 3; j++) - info->palette->data[i + j] = in[pos++]; // RGB - info->palette->data[i + 3] = 255; // alpha - } - } else if (chunkType == CHUNK_tRNS) { // tRNS: palette transparency chunk - pos += 4; // go after the 4 letters - if (info->colorType == 3) { - if (4 * chunkLength > info->palette->size) { - PNG_error = 39; // error: more alpha values given than there are palette entries - return NULL; - } - for (i = 0; i < chunkLength; i++) - info->palette->data[4 * i + 3] = in[pos++]; - } else if (info->colorType == 0) { - if (chunkLength != 2) { - PNG_error = 40; // error: this chunk must be 2 bytes for greyscale image - return NULL; - } - info->key_defined = true; - info->key_r = info->key_g = info->key_b = 256 * in[pos] + in[pos + 1]; - pos += 2; - } else if (info->colorType == 2) { - if (chunkLength != 6) { - PNG_error = 41; // error: this chunk must be 6 bytes for RGB image - return NULL; - } - info->key_defined = true; - info->key_r = 256 * in[pos] + in[pos + 1]; - pos += 2; - info->key_g = 256 * in[pos] + in[pos + 1]; - pos += 2; - info->key_b = 256 * in[pos] + in[pos + 1]; - pos += 2; - } else { - PNG_error = 42; // error: tRNS chunk not allowed for other color models - return NULL; - } - } else { // it's not an implemented chunk type, so ignore it: skip over the data - if (!(in[pos + 0] & 32)) { - // error: unknown critical chunk (5th bit of first byte of chunk type is 0) - PNG_error = 69; - return NULL; - } - pos += (chunkLength + 4); // skip 4 letters and uninterpreted data of unimplemented chunk - known_type = false; - } - pos += 4; // step over CRC (which is ignored) - } - bpp = PNG_getBpp(info); - scanlines = vector8_new(((info->width * (info->height * bpp + 7)) / 8) + info->height, 0); - PNG_error = Zlib_decompress(scanlines, idat); - if (PNG_error) - return NULL; // stop if the zlib decompressor returned an error - bytewidth = (bpp + 7) / 8; - outlength = (info->height * info->width * bpp + 7) / 8; - vector8_resize(info->image, outlength); // time to fill the out buffer - out_data = outlength ? info->image->data : 0; - if (info->interlaceMethod == 0) { // no interlace, just filter - size_t y, obp, bp; - size_t linestart, linelength; - linestart = 0; - // length in bytes of a scanline, excluding the filtertype byte - linelength = (info->width * bpp + 7) / 8; - if (bpp >= 8) // byte per byte - for (y = 0; y < info->height; y++) { - uint32_t filterType = scanlines->data[linestart]; - const uint8_t *prevline; - prevline = (y == 0) ? 0 : &out_data[(y - 1) * info->width * bytewidth]; - PNG_unFilterScanline(&out_data[linestart - y], &scanlines->data[linestart + 1], - prevline, bytewidth, filterType, linelength); - if (PNG_error) - return NULL; - linestart += (1 + linelength); // go to start of next scanline - } else { // less than 8 bits per pixel, so fill it up bit per bit - vector8_t *templine; // only used if bpp < 8 - templine = vector8_new((info->width * bpp + 7) >> 3, 0); - for (y = 0, obp = 0; y < info->height; y++) { - uint32_t filterType = scanlines->data[linestart]; - const uint8_t *prevline; - prevline = (y == 0) ? 0 : &out_data[(y - 1) * info->width * bytewidth]; - PNG_unFilterScanline(templine->data, &scanlines->data[linestart + 1], prevline, - bytewidth, filterType, linelength); - if (PNG_error) - return NULL; - for (bp = 0; bp < info->width * bpp;) - PNG_setBitOfReversedStream(&obp, out_data, PNG_readBitFromReversedStream(&bp, - templine->data)); - linestart += (1 + linelength); // go to start of next scanline - } - } - } else { // interlaceMethod is 1 (Adam7) - int i; - vector8_t *scanlineo, *scanlinen; // "old" and "new" scanline - size_t passw[7] = { - (info->width + 7) / 8, (info->width + 3) / 8, (info->width + 3) / 4, - (info->width + 1) / 4, (info->width + 1) / 2, (info->width + 0) / 2, - (info->width + 0) / 1 - }; - size_t passh[7] = { - (info->height + 7) / 8, (info->height + 7) / 8, (info->height + 3) / 8, - (info->height + 3) / 4, (info->height + 1) / 4, (info->height + 1) / 2, - (info->height + 0) / 2 - }; - size_t passstart[7] = { 0 }; - size_t pattern[28] = { 0, 4, 0, 2, 0, 1, 0, 0, 0, 4, 0, 2, 0, 1, 8, 8, 4, 4, 2, 2, 1, 8, 8, - 8, 4, 4, 2, 2 }; // values for the adam7 passes - for (i = 0; i < 6; i++) - passstart[i + 1] = passstart[i] + passh[i] * ((passw[i] ? 1 : 0) + (passw[i] * bpp + 7) / 8); - scanlineo = vector8_new((info->width * bpp + 7) / 8, 0); - scanlinen = vector8_new((info->width * bpp + 7) / 8, 0); - for (i = 0; i < 7; i++) - PNG_adam7Pass(out_data, scanlinen->data, scanlineo->data, &scanlines->data[passstart[i]], - info->width, pattern[i], pattern[i + 7], pattern[i + 14], pattern[i + 21], - passw[i], passh[i], bpp); - } - if (info->colorType != 6 || info->bitDepth != 8) { // conversion needed - vector8_t *copy = vector8_copy(info->image); // xxx: is this copy necessary? - PNG_error = PNG_convert(info, info->image, copy->data); - } - return info; -} - -/*************************************************************************************************/ - -#ifdef TEST - -#include -#include - -int main(int argc, char **argv) -{ - char *fname = (argc > 1) ? argv[1] : "test.png"; - PNG_info_t *info; - struct stat statbuf; - uint32_t insize, outsize; - FILE *infp, *outfp; - uint8_t *inbuf; - uint32_t n; - - if (stat(fname, &statbuf) != 0) { - perror("stat"); - return 1; - } else if (!statbuf.st_size) { - printf("file empty\n"); - return 1; - } - insize = (uint32_t) statbuf.st_size; - inbuf = malloc(insize); - infp = fopen(fname, "rb"); - if (!infp) { - perror("fopen"); - return 1; - } else if (fread(inbuf, 1, insize, infp) != insize) { - perror("fread"); - return 1; - } - fclose(infp); - - printf("input file: %s (size: %d)\n", fname, insize); - - info = PNG_decode(inbuf, insize); - free(inbuf); - printf("PNG_error: %d\n", PNG_error); - if (PNG_error != 0) - return 1; - - printf("width: %d, height: %d\nfirst 16 bytes: ", info->width, info->height); - for (n = 0; n < 16; n++) - printf("%02x ", info->image->data[n]); - printf("\n"); - - outsize = info->width * info->height * 4; - printf("image size: %d\n", outsize); - if (outsize != info->image->size) { - printf("error: image size doesn't match dimensions\n"); - return 1; - } - outfp = fopen("out.bin", "wb"); - if (!outfp) { - perror("fopen"); - return 1; - } else if (fwrite(info->image->data, 1, outsize, outfp) != outsize) { - perror("fwrite"); - return 1; - } - fclose(outfp); - -#ifdef ALLOC_DEBUG - png_alloc_node_t *node; - for (node = png_alloc_head, n = 1; node; node = node->next, n++) - printf("node %d (%p) addr = %p, size = %ld\n", n, node, node->addr, node->size); -#endif - png_alloc_free_all(); // also frees info and image data from PNG_decode - - return 0; -} - -#endif diff --git a/lib/picopng.h b/lib/picopng.h deleted file mode 100644 index 14c5e28..0000000 --- a/lib/picopng.h +++ /dev/null @@ -1,34 +0,0 @@ -#ifndef _PICOPNG_H -#define _PICOPNG_H - -typedef struct { - uint32_t *data; - size_t size; - size_t allocsize; -} vector32_t; - -typedef struct { - uint8_t *data; - size_t size; - size_t allocsize; -} vector8_t; - -typedef struct { - uint32_t width, height; - uint32_t colorType, bitDepth; - uint32_t compressionMethod, filterMethod, interlaceMethod; - uint32_t key_r, key_g, key_b; - bool key_defined; // is a transparent color key given? - vector8_t *palette; - vector8_t *image; -} PNG_info_t; - -PNG_info_t *PNG_decode(const uint8_t *in, uint32_t size); -void png_alloc_free_all(void); - -unsigned picopng_zlib_decompress(unsigned char* out, size_t outsize, - const unsigned char* in, size_t insize); - -extern int PNG_error; - -#endif diff --git a/lib/png.c b/lib/png.c deleted file mode 100644 index f71fc6a..0000000 --- a/lib/png.c +++ /dev/null @@ -1,89 +0,0 @@ -#include -#include -#include -#include -#include -#include -#include -#include -#include - -#include "png.h" - -z_stream png_stream; -static int initialized; - -int png_uncompress_init(void) -{ - if (!initialized++) { - png_stream.workspace = malloc(zlib_inflate_workspacesize()); - if (!png_stream.workspace) { - initialized = 0; - return -ENOMEM; - } - png_stream.next_in = NULL; - png_stream.avail_in = 0; - zlib_inflateInit(&png_stream); - } - return 0; -} - -void png_uncompress_exit(void) -{ - if (!--initialized) { - zlib_inflateEnd(&png_stream); - vfree(png_stream.workspace); - } -} - -static int png_renderer(struct fb_info *info, struct image *img, void* fb, - int startx, int starty, void* offscreenbuf) -{ - int width, height; - void *buf; - int xres, yres; - - xres = info->xres; - yres = info->yres; - - if (startx < 0) { - startx = (xres - img->width) / 2; - if (startx < 0) - startx = 0; - } - - if (starty < 0) { - starty = (yres - img->height) / 2; - if (starty < 0) - starty = 0; - } - - width = min(img->width, xres - startx); - height = min(img->height, yres - starty); - - buf = offscreenbuf ? offscreenbuf : fb; - - rgba_blend(info, img->data, buf, height, width, startx, starty, true); - - if (offscreenbuf) { - int fbsize; - - fbsize = xres * yres * (info->bits_per_pixel >> 3); - memcpy(fb, offscreenbuf, fbsize); - } - - return img->height; -} - -static struct image_renderer png = { - .type = filetype_png, - .open = png_open, - .close = png_close, - .renderer = png_renderer, -}; - -static int png_init(void) -{ - return image_renderer_register(&png); -} -fs_initcall(png_init); diff --git a/lib/png.h b/lib/png.h deleted file mode 100644 index 3ac9364..0000000 --- a/lib/png.h +++ /dev/null @@ -1,21 +0,0 @@ -/* - * Copyright (C) 2012 Jean-Christophe PLAGNIOL-VILLARD - * - * GPL v2 - */ - -#ifndef __PNG_H__ -#define __PNG_H__ - -#include -#include -#include -#include - -int png_uncompress_init(void); -void png_uncompress_exit(void); -void png_close(struct image *img); -struct image *png_open(char *inbuf, int insize); -extern z_stream png_stream; - -#endif /* __PNG_H__ */ diff --git a/lib/png_lode.c b/lib/png_lode.c deleted file mode 100644 index 4b57f6a..0000000 --- a/lib/png_lode.c +++ /dev/null @@ -1,90 +0,0 @@ -#include -#include -#include -#include -#include -#include -#include -#include -#include - -#include "lodepng.h" -#include "png.h" - -unsigned lodepng_custom_zlib_decompress(unsigned char** out, size_t* outsize, - const unsigned char* in, size_t insize, - const LodePNGDecompressSettings* settings) -{ - int err; - - png_stream.next_in = in; - png_stream.avail_in = insize; - - png_stream.next_out = *out; - png_stream.avail_out = *outsize; - - err = zlib_inflateReset(&png_stream); - if (err != Z_OK) { - printk("zlib_inflateReset error %d\n", err); - zlib_inflateEnd(&png_stream); - zlib_inflateInit(&png_stream); - } - - err = zlib_inflate(&png_stream, Z_FINISH); - if (err != Z_STREAM_END) - goto err; - return 0; - -err: - printk("Error %d while decompressing!\n", err); - printk("%p(%zd)->%p(%zd)\n", in, insize, *out, *outsize); - return -EIO; -} - -struct image *png_open(char *inbuf, int insize) -{ - LodePNGState state; - int ret; - unsigned error; - struct image *img = calloc(1, sizeof(struct image)); - unsigned char *png; - - if (!img) - return ERR_PTR(-ENOMEM); - - ret = png_uncompress_init(); - if (ret) - goto err; - - lodepng_state_init(&state); - - state.info_raw.colortype = LCT_RGBA; - state.info_raw.bitdepth = 8; - - error = lodepng_decode(&png, &img->width, &img->height, &state, inbuf, insize); - - if(error) { - printf("error %u: %s\n", error, lodepng_error_text(error)); - ret = -EINVAL; - goto err; - } - - img->bits_per_pixel = 4 << 3; - img->data = png; - - pr_debug("png: %d x %d data@0x%p\n", img->width, img->height, img->data); - - lodepng_state_cleanup(&state); - - return img; -err: - free(png); - free(img); - return ERR_PTR(ret); -} - -void png_close(struct image *img) -{ - free(img->data); - png_uncompress_exit(); -} diff --git a/lib/png_pico.c b/lib/png_pico.c deleted file mode 100644 index a0127f7..0000000 --- a/lib/png_pico.c +++ /dev/null @@ -1,85 +0,0 @@ -#include -#include -#include -#include -#include -#include -#include -#include -#include - -#include "picopng.h" -#include "png.h" - -unsigned picopng_zlib_decompress(unsigned char* out, size_t outsize, - const unsigned char* in, size_t insize) -{ - int err; - - png_stream.next_in = in; - png_stream.avail_in = insize; - - png_stream.next_out = out; - png_stream.avail_out = outsize; - - err = zlib_inflateReset(&png_stream); - if (err != Z_OK) { - printk("zlib_inflateReset error %d\n", err); - zlib_inflateEnd(&png_stream); - zlib_inflateInit(&png_stream); - } - - err = zlib_inflate(&png_stream, Z_FINISH); - if (err != Z_STREAM_END) - goto err; - return 0; - -err: - printk("Error %d while decompressing!\n", err); - printk("%p(%zd)->%p(%zd)\n", in, insize, out, outsize); - return -EIO; -} - -struct image *png_open(char *inbuf, int insize) -{ - PNG_info_t *png_info; - int ret; - struct image *img = calloc(1, sizeof(struct image)); - - if (!img) - return ERR_PTR(-ENOMEM); - - ret = png_uncompress_init(); - if (ret) - goto err; - - /* rgba */ - png_info = PNG_decode(inbuf, insize); - - if(PNG_error) { - printf("error %u:\n", PNG_error); - ret = -EINVAL; - goto err; - } - - img->width = png_info->width; - img->height = png_info->height; - img->bits_per_pixel = 4 << 3; - img->data = png_info->image->data; - - pr_debug("png: %d x %d data@0x%p\n", img->width, img->height, img->data); - - png_alloc_free_all(); - - return img; -err: - png_alloc_free_all(); - free(img); - return ERR_PTR(ret); -} - -void png_close(struct image *img) -{ - free(img->data); - png_alloc_free_all(); -}