From 8cded28c45e65498591773635a43f0ac749aff4c Mon Sep 17 00:00:00 2001 From: AnnieL Date: Tue, 15 Mar 2016 19:30:23 +0000 Subject: [PATCH] Updates stb_image from 1.33 to 2.10 Updates stb_image from 1.33 to 2.10 which deprecates stb_image.c and uses only stb_image.h --- rpcs3/Emu/SysCalls/Modules/cellGifDec.cpp | 4 +- rpcs3/Emu/SysCalls/Modules/cellJpgDec.cpp | 4 +- rpcs3/stb_image.cpp | 11 +- stblib/stb_image.c | 4401 -------------- stblib/stb_image.h | 6719 ++++++++++++++++++++- 5 files changed, 6549 insertions(+), 4590 deletions(-) delete mode 100644 stblib/stb_image.c diff --git a/rpcs3/Emu/SysCalls/Modules/cellGifDec.cpp b/rpcs3/Emu/SysCalls/Modules/cellGifDec.cpp index b8a9484ce2..97aa40ae3c 100644 --- a/rpcs3/Emu/SysCalls/Modules/cellGifDec.cpp +++ b/rpcs3/Emu/SysCalls/Modules/cellGifDec.cpp @@ -4,10 +4,8 @@ #include "Emu/IdManager.h" #include "Emu/SysCalls/Modules.h" -extern "C" -{ +// STB_IMAGE_IMPLEMENTATION is already defined in stb_image.cpp #include "stblib/stb_image.h" -} #include "Emu/FS/VFS.h" #include "Emu/FS/vfsFileBase.h" diff --git a/rpcs3/Emu/SysCalls/Modules/cellJpgDec.cpp b/rpcs3/Emu/SysCalls/Modules/cellJpgDec.cpp index 59f6ff6b39..e2d235a19a 100644 --- a/rpcs3/Emu/SysCalls/Modules/cellJpgDec.cpp +++ b/rpcs3/Emu/SysCalls/Modules/cellJpgDec.cpp @@ -4,10 +4,8 @@ #include "Emu/IdManager.h" #include "Emu/SysCalls/Modules.h" -extern "C" -{ +// STB_IMAGE_IMPLEMENTATION is already defined in stb_image.cpp #include "stblib/stb_image.h" -} #include "Emu/FS/VFS.h" #include "Emu/FS/vfsFileBase.h" diff --git a/rpcs3/stb_image.cpp b/rpcs3/stb_image.cpp index 144dbdd192..404192759a 100644 --- a/rpcs3/stb_image.cpp +++ b/rpcs3/stb_image.cpp @@ -1,9 +1,4 @@ #include "stdafx.h" - -extern "C" -{ -#pragma warning(push, 0) -#include "stblib/stb_image.h" -#include "stblib/stb_image.c" -#pragma warning(pop) -} +// Defines STB_IMAGE_IMPLEMENTATION *once* before including stb_image.h (as said in stb_image.h's comments) +#define STB_IMAGE_IMPLEMENTATION +#include "stblib/stb_image.h" \ No newline at end of file diff --git a/stblib/stb_image.c b/stblib/stb_image.c deleted file mode 100644 index c1d494f8dd..0000000000 --- a/stblib/stb_image.c +++ /dev/null @@ -1,4401 +0,0 @@ -/* stbi-1.33 - public domain JPEG/PNG reader - http://nothings.org/stb_image.c - when you control the images you're loading - no warranty implied; use at your own risk - - QUICK NOTES: - Primarily of interest to game developers and other people who can - avoid problematic images and only need the trivial interface - - JPEG baseline (no JPEG progressive) - PNG 8-bit only - - TGA (not sure what subset, if a subset) - BMP non-1bpp, non-RLE - PSD (composited view only, no extra channels) - - GIF (*comp always reports as 4-channel) - HDR (radiance rgbE format) - PIC (Softimage PIC) - - - decode from memory or through FILE (define STBI_NO_STDIO to remove code) - - decode from arbitrary I/O callbacks - - overridable dequantizing-IDCT, YCbCr-to-RGB conversion (define STBI_SIMD) - - Latest revisions: - 1.33 (2011-07-14) minor fixes suggested by Dave Moore - 1.32 (2011-07-13) info support for all filetypes (SpartanJ) - 1.31 (2011-06-19) a few more leak fixes, bug in PNG handling (SpartanJ) - 1.30 (2011-06-11) added ability to load files via io callbacks (Ben Wenger) - 1.29 (2010-08-16) various warning fixes from Aurelien Pocheville - - See end of file for full revision history. - - TODO: - stbi_info support for BMP,PSD,HDR,PIC - - - ============================ Contributors ========================= - - Image formats Optimizations & bugfixes - Sean Barrett (jpeg, png, bmp) Fabian "ryg" Giesen - Nicolas Schulz (hdr, psd) - Jonathan Dummer (tga) Bug fixes & warning fixes - Jean-Marc Lienher (gif) Marc LeBlanc - Tom Seddon (pic) Christpher Lloyd - Thatcher Ulrich (psd) Dave Moore - Won Chun - the Horde3D community - Extensions, features Janez Zemva - Jetro Lauha (stbi_info) Jonathan Blow - James "moose2000" Brown (iPhone PNG) Laurent Gomila - Ben "Disch" Wenger (io callbacks) Aruelien Pocheville - Martin "SpartanJ" Golini Ryamond Barbiero - David Woo - - - If your name should be here but isn't, let Sean know. - -*/ - -#ifndef STBI_HEADER_FILE_ONLY - -#ifndef STBI_NO_HDR -#include // ldexp -#include // strcmp, strtok -#endif - -#ifndef STBI_NO_STDIO -#include -#endif -#include -#include -#include -#include - -#ifndef _MSC_VER - #ifdef __cplusplus - #define stbi_inline inline - #else - #define stbi_inline - #endif -#else - #define stbi_inline __forceinline -#endif - - -// implementation: -typedef unsigned char uint8; -typedef unsigned short uint16; -typedef signed short int16; -typedef unsigned int uint32; -typedef signed int int32; -typedef unsigned int uint; - -// should produce compiler error if size is wrong -typedef unsigned char validate_uint32[sizeof(uint32)==4 ? 1 : -1]; - -#if defined(STBI_NO_STDIO) && !defined(STBI_NO_WRITE) -#define STBI_NO_WRITE -#endif - -#define STBI_NOTUSED(v) (void)sizeof(v) - -#ifdef _MSC_VER -#define STBI_HAS_LROTL -#endif - -#ifdef STBI_HAS_LROTL - #define stbi_lrot(x,y) _lrotl(x,y) -#else - #define stbi_lrot(x,y) (((x) << (y)) | ((x) >> (32 - (y)))) -#endif - -/////////////////////////////////////////////// -// -// stbi struct and start_xxx functions - -// stbi structure is our basic context used by all images, so it -// contains all the IO context, plus some basic image information -typedef struct -{ - uint32 img_x, img_y; - int img_n, img_out_n; - - stbi_io_callbacks io; - void *io_user_data; - - int read_from_callbacks; - int buflen; - uint8 buffer_start[128]; - - uint8 *img_buffer, *img_buffer_end; - uint8 *img_buffer_original; -} stbi; - - -static void refill_buffer(stbi *s); - -// initialize a memory-decode context -static void start_mem(stbi *s, uint8 const *buffer, int len) -{ - s->io.read = NULL; - s->read_from_callbacks = 0; - s->img_buffer = s->img_buffer_original = (uint8 *) buffer; - s->img_buffer_end = (uint8 *) buffer+len; -} - -// initialize a callback-based context -static void start_callbacks(stbi *s, stbi_io_callbacks *c, void *user) -{ - s->io = *c; - s->io_user_data = user; - s->buflen = sizeof(s->buffer_start); - s->read_from_callbacks = 1; - s->img_buffer_original = s->buffer_start; - refill_buffer(s); -} - -#ifndef STBI_NO_STDIO - -static int stdio_read(void *user, char *data, int size) -{ - return (int) fread(data,1,size,(FILE*) user); -} - -static void stdio_skip(void *user, unsigned n) -{ - fseek((FILE*) user, n, SEEK_CUR); -} - -static int stdio_eof(void *user) -{ - return feof((FILE*) user); -} - -static stbi_io_callbacks stbi_stdio_callbacks = -{ - stdio_read, - stdio_skip, - stdio_eof, -}; - -static void start_file(stbi *s, FILE *f) -{ - start_callbacks(s, &stbi_stdio_callbacks, (void *) f); -} - -//static void stop_file(stbi *s) { } - -#endif // !STBI_NO_STDIO - -static void stbi_rewind(stbi *s) -{ - // conceptually rewind SHOULD rewind to the beginning of the stream, - // but we just rewind to the beginning of the initial buffer, because - // we only use it after doing 'test', which only ever looks at at most 92 bytes - s->img_buffer = s->img_buffer_original; -} - -static int stbi_jpeg_test(stbi *s); -static stbi_uc *stbi_jpeg_load(stbi *s, int *x, int *y, int *comp, int req_comp); -static int stbi_jpeg_info(stbi *s, int *x, int *y, int *comp); -static int stbi_png_test(stbi *s); -static stbi_uc *stbi_png_load(stbi *s, int *x, int *y, int *comp, int req_comp); -static int stbi_png_info(stbi *s, int *x, int *y, int *comp); -static int stbi_bmp_test(stbi *s); -static stbi_uc *stbi_bmp_load(stbi *s, int *x, int *y, int *comp, int req_comp); -static int stbi_tga_test(stbi *s); -static stbi_uc *stbi_tga_load(stbi *s, int *x, int *y, int *comp, int req_comp); -static int stbi_tga_info(stbi *s, int *x, int *y, int *comp); -static int stbi_psd_test(stbi *s); -static stbi_uc *stbi_psd_load(stbi *s, int *x, int *y, int *comp, int req_comp); -static int stbi_hdr_test(stbi *s); -static float *stbi_hdr_load(stbi *s, int *x, int *y, int *comp, int req_comp); -static int stbi_pic_test(stbi *s); -static stbi_uc *stbi_pic_load(stbi *s, int *x, int *y, int *comp, int req_comp); -static int stbi_gif_test(stbi *s); -static stbi_uc *stbi_gif_load(stbi *s, int *x, int *y, int *comp, int req_comp); -static int stbi_gif_info(stbi *s, int *x, int *y, int *comp); - - -// this is not threadsafe -static const char *failure_reason; - -const char *stbi_failure_reason(void) -{ - return failure_reason; -} - -static int e(const char *str) -{ - failure_reason = str; - return 0; -} - -// e - error -// epf - error returning pointer to float -// epuc - error returning pointer to unsigned char - -#ifdef STBI_NO_FAILURE_STRINGS - #define e(x,y) 0 -#elif defined(STBI_FAILURE_USERMSG) - #define e(x,y) e(y) -#else - #define e(x,y) e(x) -#endif - -#define epf(x,y) ((float *) (e(x,y)?NULL:NULL)) -#define epuc(x,y) ((unsigned char *) (e(x,y)?NULL:NULL)) - -void stbi_image_free(void *retval_from_stbi_load) -{ - free(retval_from_stbi_load); -} - -#ifndef STBI_NO_HDR -static float *ldr_to_hdr(stbi_uc *data, int x, int y, int comp); -static stbi_uc *hdr_to_ldr(float *data, int x, int y, int comp); -#endif - -static unsigned char *stbi_load_main(stbi *s, int *x, int *y, int *comp, int req_comp) -{ - if (stbi_jpeg_test(s)) return stbi_jpeg_load(s,x,y,comp,req_comp); - if (stbi_png_test(s)) return stbi_png_load(s,x,y,comp,req_comp); - if (stbi_bmp_test(s)) return stbi_bmp_load(s,x,y,comp,req_comp); - if (stbi_gif_test(s)) return stbi_gif_load(s,x,y,comp,req_comp); - if (stbi_psd_test(s)) return stbi_psd_load(s,x,y,comp,req_comp); - if (stbi_pic_test(s)) return stbi_pic_load(s,x,y,comp,req_comp); - - #ifndef STBI_NO_HDR - if (stbi_hdr_test(s)) { - float *hdr = stbi_hdr_load(s, x,y,comp,req_comp); - return hdr_to_ldr(hdr, *x, *y, req_comp ? req_comp : *comp); - } - #endif - - // test tga last because it's a crappy test! - if (stbi_tga_test(s)) - return stbi_tga_load(s,x,y,comp,req_comp); - return epuc("unknown image type", "Image not of any known type, or corrupt"); -} - -#ifndef STBI_NO_STDIO -unsigned char *stbi_load(char const *filename, int *x, int *y, int *comp, int req_comp) -{ - FILE *f = fopen(filename, "rb"); - unsigned char *result; - if (!f) return epuc("can't fopen", "Unable to open file"); - result = stbi_load_from_file(f,x,y,comp,req_comp); - fclose(f); - return result; -} - -unsigned char *stbi_load_from_file(FILE *f, int *x, int *y, int *comp, int req_comp) -{ - stbi s; - start_file(&s,f); - return stbi_load_main(&s,x,y,comp,req_comp); -} -#endif //!STBI_NO_STDIO - -unsigned char *stbi_load_from_memory(stbi_uc const *buffer, int len, int *x, int *y, int *comp, int req_comp) -{ - stbi s; - start_mem(&s,buffer,len); - return stbi_load_main(&s,x,y,comp,req_comp); -} - -unsigned char *stbi_load_from_callbacks(stbi_io_callbacks const *clbk, void *user, int *x, int *y, int *comp, int req_comp) -{ - stbi s; - start_callbacks(&s, (stbi_io_callbacks *) clbk, user); - return stbi_load_main(&s,x,y,comp,req_comp); -} - -#ifndef STBI_NO_HDR - -float *stbi_loadf_main(stbi *s, int *x, int *y, int *comp, int req_comp) -{ - unsigned char *data; - #ifndef STBI_NO_HDR - if (stbi_hdr_test(s)) - return stbi_hdr_load(s,x,y,comp,req_comp); - #endif - data = stbi_load_main(s, x, y, comp, req_comp); - if (data) - return ldr_to_hdr(data, *x, *y, req_comp ? req_comp : *comp); - return epf("unknown image type", "Image not of any known type, or corrupt"); -} - -float *stbi_loadf_from_memory(stbi_uc const *buffer, int len, int *x, int *y, int *comp, int req_comp) -{ - stbi s; - start_mem(&s,buffer,len); - return stbi_loadf_main(&s,x,y,comp,req_comp); -} - -float *stbi_loadf_from_callbacks(stbi_io_callbacks const *clbk, void *user, int *x, int *y, int *comp, int req_comp) -{ - stbi s; - start_callbacks(&s, (stbi_io_callbacks *) clbk, user); - return stbi_loadf_main(&s,x,y,comp,req_comp); -} - -#ifndef STBI_NO_STDIO -float *stbi_loadf(char const *filename, int *x, int *y, int *comp, int req_comp) -{ - FILE *f = fopen(filename, "rb"); - float *result; - if (!f) return epf("can't fopen", "Unable to open file"); - result = stbi_loadf_from_file(f,x,y,comp,req_comp); - fclose(f); - return result; -} - -float *stbi_loadf_from_file(FILE *f, int *x, int *y, int *comp, int req_comp) -{ - stbi s; - start_file(&s,f); - return stbi_loadf_main(&s,x,y,comp,req_comp); -} -#endif // !STBI_NO_STDIO - -#endif // !STBI_NO_HDR - -// these is-hdr-or-not is defined independent of whether STBI_NO_HDR is -// defined, for API simplicity; if STBI_NO_HDR is defined, it always -// reports false! - -int stbi_is_hdr_from_memory(stbi_uc const *buffer, int len) -{ - #ifndef STBI_NO_HDR - stbi s; - start_mem(&s,buffer,len); - return stbi_hdr_test(&s); - #else - STBI_NOTUSED(buffer); - STBI_NOTUSED(len); - return 0; - #endif -} - -#ifndef STBI_NO_STDIO -extern int stbi_is_hdr (char const *filename) -{ - FILE *f = fopen(filename, "rb"); - int result=0; - if (f) { - result = stbi_is_hdr_from_file(f); - fclose(f); - } - return result; -} - -extern int stbi_is_hdr_from_file(FILE *f) -{ - #ifndef STBI_NO_HDR - stbi s; - start_file(&s,f); - return stbi_hdr_test(&s); - #else - return 0; - #endif -} -#endif // !STBI_NO_STDIO - -extern int stbi_is_hdr_from_callbacks(stbi_io_callbacks const *clbk, void *user) -{ - #ifndef STBI_NO_HDR - stbi s; - start_callbacks(&s, (stbi_io_callbacks *) clbk, user); - return stbi_hdr_test(&s); - #else - return 0; - #endif -} - -#ifndef STBI_NO_HDR -static float h2l_gamma_i=1.0f/2.2f, h2l_scale_i=1.0f; -static float l2h_gamma=2.2f, l2h_scale=1.0f; - -void stbi_hdr_to_ldr_gamma(float gamma) { h2l_gamma_i = 1/gamma; } -void stbi_hdr_to_ldr_scale(float scale) { h2l_scale_i = 1/scale; } - -void stbi_ldr_to_hdr_gamma(float gamma) { l2h_gamma = gamma; } -void stbi_ldr_to_hdr_scale(float scale) { l2h_scale = scale; } -#endif - - -////////////////////////////////////////////////////////////////////////////// -// -// Common code used by all image loaders -// - -enum -{ - SCAN_load=0, - SCAN_type, - SCAN_header -}; - -static void refill_buffer(stbi *s) -{ - int n = (s->io.read)(s->io_user_data,(char*)s->buffer_start,s->buflen); - if (n == 0) { - // at end of file, treat same as if from memory - s->read_from_callbacks = 0; - s->img_buffer = s->img_buffer_end-1; - *s->img_buffer = 0; - } else { - s->img_buffer = s->buffer_start; - s->img_buffer_end = s->buffer_start + n; - } -} - -stbi_inline static int get8(stbi *s) -{ - if (s->img_buffer < s->img_buffer_end) - return *s->img_buffer++; - if (s->read_from_callbacks) { - refill_buffer(s); - return *s->img_buffer++; - } - return 0; -} - -stbi_inline static int at_eof(stbi *s) -{ - if (s->io.read) { - if (!(s->io.eof)(s->io_user_data)) return 0; - // if feof() is true, check if buffer = end - // special case: we've only got the special 0 character at the end - if (s->read_from_callbacks == 0) return 1; - } - - return s->img_buffer >= s->img_buffer_end; -} - -stbi_inline static uint8 get8u(stbi *s) -{ - return (uint8) get8(s); -} - -static void skip(stbi *s, int n) -{ - if (s->io.read) { - int blen = s->img_buffer_end - s->img_buffer; - if (blen < n) { - s->img_buffer = s->img_buffer_end; - (s->io.skip)(s->io_user_data, n - blen); - return; - } - } - s->img_buffer += n; -} - -static int getn(stbi *s, stbi_uc *buffer, int n) -{ - if (s->io.read) { - int blen = s->img_buffer_end - s->img_buffer; - if (blen < n) { - int res, count; - - memcpy(buffer, s->img_buffer, blen); - - count = (s->io.read)(s->io_user_data, (char*) buffer + blen, n - blen); - res = (count == (n-blen)); - s->img_buffer = s->img_buffer_end; - return res; - } - } - - if (s->img_buffer+n <= s->img_buffer_end) { - memcpy(buffer, s->img_buffer, n); - s->img_buffer += n; - return 1; - } else - return 0; -} - -static int get16(stbi *s) -{ - int z = get8(s); - return (z << 8) + get8(s); -} - -static uint32 get32(stbi *s) -{ - uint32 z = get16(s); - return (z << 16) + get16(s); -} - -static int get16le(stbi *s) -{ - int z = get8(s); - return z + (get8(s) << 8); -} - -static uint32 get32le(stbi *s) -{ - uint32 z = get16le(s); - return z + (get16le(s) << 16); -} - -////////////////////////////////////////////////////////////////////////////// -// -// generic converter from built-in img_n to req_comp -// individual types do this automatically as much as possible (e.g. jpeg -// does all cases internally since it needs to colorspace convert anyway, -// and it never has alpha, so very few cases ). png can automatically -// interleave an alpha=255 channel, but falls back to this for other cases -// -// assume data buffer is malloced, so malloc a new one and free that one -// only failure mode is malloc failing - -static uint8 compute_y(int r, int g, int b) -{ - return (uint8) (((r*77) + (g*150) + (29*b)) >> 8); -} - -static unsigned char *convert_format(unsigned char *data, int img_n, int req_comp, uint x, uint y) -{ - int i,j; - unsigned char *good; - - if (req_comp == img_n) return data; - assert(req_comp >= 1 && req_comp <= 4); - - good = (unsigned char *) malloc(req_comp * x * y); - if (good == NULL) { - free(data); - return epuc("outofmem", "Out of memory"); - } - - for (j=0; j < (int) y; ++j) { - unsigned char *src = data + j * x * img_n ; - unsigned char *dest = good + j * x * req_comp; - - #define COMBO(a,b) ((a)*8+(b)) - #define CASE(a,b) case COMBO(a,b): for(i=x-1; i >= 0; --i, src += a, dest += b) - // convert source image with img_n components to one with req_comp components; - // avoid switch per pixel, so use switch per scanline and massive macros - switch (COMBO(img_n, req_comp)) { - CASE(1,2) dest[0]=src[0], dest[1]=255; break; - CASE(1,3) dest[0]=dest[1]=dest[2]=src[0]; break; - CASE(1,4) dest[0]=dest[1]=dest[2]=src[0], dest[3]=255; break; - CASE(2,1) dest[0]=src[0]; break; - CASE(2,3) dest[0]=dest[1]=dest[2]=src[0]; break; - CASE(2,4) dest[0]=dest[1]=dest[2]=src[0], dest[3]=src[1]; break; - CASE(3,4) dest[0]=src[0],dest[1]=src[1],dest[2]=src[2],dest[3]=255; break; - CASE(3,1) dest[0]=compute_y(src[0],src[1],src[2]); break; - CASE(3,2) dest[0]=compute_y(src[0],src[1],src[2]), dest[1] = 255; break; - CASE(4,1) dest[0]=compute_y(src[0],src[1],src[2]); break; - CASE(4,2) dest[0]=compute_y(src[0],src[1],src[2]), dest[1] = src[3]; break; - CASE(4,3) dest[0]=src[0],dest[1]=src[1],dest[2]=src[2]; break; - default: assert(0); - } - #undef CASE - } - - free(data); - return good; -} - -#ifndef STBI_NO_HDR -static float *ldr_to_hdr(stbi_uc *data, int x, int y, int comp) -{ - int i,k,n; - float *output = (float *) malloc(x * y * comp * sizeof(float)); - if (output == NULL) { free(data); return epf("outofmem", "Out of memory"); } - // compute number of non-alpha components - if (comp & 1) n = comp; else n = comp-1; - for (i=0; i < x*y; ++i) { - for (k=0; k < n; ++k) { - output[i*comp + k] = (float) pow(data[i*comp+k]/255.0f, l2h_gamma) * l2h_scale; - } - if (k < comp) output[i*comp + k] = data[i*comp+k]/255.0f; - } - free(data); - return output; -} - -#define float2int(x) ((int) (x)) -static stbi_uc *hdr_to_ldr(float *data, int x, int y, int comp) -{ - int i,k,n; - stbi_uc *output = (stbi_uc *) malloc(x * y * comp); - if (output == NULL) { free(data); return epuc("outofmem", "Out of memory"); } - // compute number of non-alpha components - if (comp & 1) n = comp; else n = comp-1; - for (i=0; i < x*y; ++i) { - for (k=0; k < n; ++k) { - float z = (float) pow(data[i*comp+k]*h2l_scale_i, h2l_gamma_i) * 255 + 0.5f; - if (z < 0) z = 0; - if (z > 255) z = 255; - output[i*comp + k] = (uint8) float2int(z); - } - if (k < comp) { - float z = data[i*comp+k] * 255 + 0.5f; - if (z < 0) z = 0; - if (z > 255) z = 255; - output[i*comp + k] = (uint8) float2int(z); - } - } - free(data); - return output; -} -#endif - -////////////////////////////////////////////////////////////////////////////// -// -// "baseline" JPEG/JFIF decoder (not actually fully baseline implementation) -// -// simple implementation -// - channel subsampling of at most 2 in each dimension -// - doesn't support delayed output of y-dimension -// - simple interface (only one output format: 8-bit interleaved RGB) -// - doesn't try to recover corrupt jpegs -// - doesn't allow partial loading, loading multiple at once -// - still fast on x86 (copying globals into locals doesn't help x86) -// - allocates lots of intermediate memory (full size of all components) -// - non-interleaved case requires this anyway -// - allows good upsampling (see next) -// high-quality -// - upsampled channels are bilinearly interpolated, even across blocks -// - quality integer IDCT derived from IJG's 'slow' -// performance -// - fast huffman; reasonable integer IDCT -// - uses a lot of intermediate memory, could cache poorly -// - load http://nothings.org/remote/anemones.jpg 3 times on 2.8Ghz P4 -// stb_jpeg: 1.34 seconds (MSVC6, default release build) -// stb_jpeg: 1.06 seconds (MSVC6, processor = Pentium Pro) -// IJL11.dll: 1.08 seconds (compiled by intel) -// IJG 1998: 0.98 seconds (MSVC6, makefile provided by IJG) -// IJG 1998: 0.95 seconds (MSVC6, makefile + proc=PPro) - -// huffman decoding acceleration -#define FAST_BITS 9 // larger handles more cases; smaller stomps less cache - -typedef struct -{ - uint8 fast[1 << FAST_BITS]; - // weirdly, repacking this into AoS is a 10% speed loss, instead of a win - uint16 code[256]; - uint8 values[256]; - uint8 size[257]; - unsigned int maxcode[18]; - int delta[17]; // old 'firstsymbol' - old 'firstcode' -} huffman; - -typedef struct -{ - #ifdef STBI_SIMD - unsigned short dequant2[4][64]; - #endif - stbi *s; - huffman huff_dc[4]; - huffman huff_ac[4]; - uint8 dequant[4][64]; - -// sizes for components, interleaved MCUs - int img_h_max, img_v_max; - int img_mcu_x, img_mcu_y; - int img_mcu_w, img_mcu_h; - -// definition of jpeg image component - struct - { - int id; - int h,v; - int tq; - int hd,ha; - int dc_pred; - - int x,y,w2,h2; - uint8 *data; - void *raw_data; - uint8 *linebuf; - } img_comp[4]; - - uint32 code_buffer; // jpeg entropy-coded buffer - int code_bits; // number of valid bits - unsigned char marker; // marker seen while filling entropy buffer - int nomore; // flag if we saw a marker so must stop - - int scan_n, order[4]; - int restart_interval, todo; -} jpeg; - -static int build_huffman(huffman *h, int *count) -{ - int i,j,k=0,code; - // build size list for each symbol (from JPEG spec) - for (i=0; i < 16; ++i) - for (j=0; j < count[i]; ++j) - h->size[k++] = (uint8) (i+1); - h->size[k] = 0; - - // compute actual symbols (from jpeg spec) - code = 0; - k = 0; - for(j=1; j <= 16; ++j) { - // compute delta to add to code to compute symbol id - h->delta[j] = k - code; - if (h->size[k] == j) { - while (h->size[k] == j) - h->code[k++] = (uint16) (code++); - if (code-1 >= (1 << j)) return e("bad code lengths","Corrupt JPEG"); - } - // compute largest code + 1 for this size, preshifted as needed later - h->maxcode[j] = code << (16-j); - code <<= 1; - } - h->maxcode[j] = 0xffffffff; - - // build non-spec acceleration table; 255 is flag for not-accelerated - memset(h->fast, 255, 1 << FAST_BITS); - for (i=0; i < k; ++i) { - int s = h->size[i]; - if (s <= FAST_BITS) { - int c = h->code[i] << (FAST_BITS-s); - int m = 1 << (FAST_BITS-s); - for (j=0; j < m; ++j) { - h->fast[c+j] = (uint8) i; - } - } - } - return 1; -} - -static void grow_buffer_unsafe(jpeg *j) -{ - do { - int b = j->nomore ? 0 : get8(j->s); - if (b == 0xff) { - int c = get8(j->s); - if (c != 0) { - j->marker = (unsigned char) c; - j->nomore = 1; - return; - } - } - j->code_buffer |= b << (24 - j->code_bits); - j->code_bits += 8; - } while (j->code_bits <= 24); -} - -// (1 << n) - 1 -static uint32 bmask[17]={0,1,3,7,15,31,63,127,255,511,1023,2047,4095,8191,16383,32767,65535}; - -// decode a jpeg huffman value from the bitstream -stbi_inline static int decode(jpeg *j, huffman *h) -{ - unsigned int temp; - int c,k; - - if (j->code_bits < 16) grow_buffer_unsafe(j); - - // look at the top FAST_BITS and determine what symbol ID it is, - // if the code is <= FAST_BITS - c = (j->code_buffer >> (32 - FAST_BITS)) & ((1 << FAST_BITS)-1); - k = h->fast[c]; - if (k < 255) { - int s = h->size[k]; - if (s > j->code_bits) - return -1; - j->code_buffer <<= s; - j->code_bits -= s; - return h->values[k]; - } - - // naive test is to shift the code_buffer down so k bits are - // valid, then test against maxcode. To speed this up, we've - // preshifted maxcode left so that it has (16-k) 0s at the - // end; in other words, regardless of the number of bits, it - // wants to be compared against something shifted to have 16; - // that way we don't need to shift inside the loop. - temp = j->code_buffer >> 16; - for (k=FAST_BITS+1 ; ; ++k) - if (temp < h->maxcode[k]) - break; - if (k == 17) { - // error! code not found - j->code_bits -= 16; - return -1; - } - - if (k > j->code_bits) - return -1; - - // convert the huffman code to the symbol id - c = ((j->code_buffer >> (32 - k)) & bmask[k]) + h->delta[k]; - assert((((j->code_buffer) >> (32 - h->size[c])) & bmask[h->size[c]]) == h->code[c]); - - // convert the id to a symbol - j->code_bits -= k; - j->code_buffer <<= k; - return h->values[c]; -} - -// combined JPEG 'receive' and JPEG 'extend', since baseline -// always extends everything it receives. -stbi_inline static int extend_receive(jpeg *j, int n) -{ - unsigned int m = 1 << (n-1); - unsigned int k; - if (j->code_bits < n) grow_buffer_unsafe(j); - - #if 1 - k = stbi_lrot(j->code_buffer, n); - j->code_buffer = k & ~bmask[n]; - k &= bmask[n]; - j->code_bits -= n; - #else - k = (j->code_buffer >> (32 - n)) & bmask[n]; - j->code_bits -= n; - j->code_buffer <<= n; - #endif - // the following test is probably a random branch that won't - // predict well. I tried to table accelerate it but failed. - // maybe it's compiling as a conditional move? - if (k < m) - return (-1 << n) + k + 1; - else - return k; -} - -// given a value that's at position X in the zigzag stream, -// where does it appear in the 8x8 matrix coded as row-major? -static uint8 dezigzag[64+15] = -{ - 0, 1, 8, 16, 9, 2, 3, 10, - 17, 24, 32, 25, 18, 11, 4, 5, - 12, 19, 26, 33, 40, 48, 41, 34, - 27, 20, 13, 6, 7, 14, 21, 28, - 35, 42, 49, 56, 57, 50, 43, 36, - 29, 22, 15, 23, 30, 37, 44, 51, - 58, 59, 52, 45, 38, 31, 39, 46, - 53, 60, 61, 54, 47, 55, 62, 63, - // let corrupt input sample past end - 63, 63, 63, 63, 63, 63, 63, 63, - 63, 63, 63, 63, 63, 63, 63 -}; - -// decode one 64-entry block-- -static int decode_block(jpeg *j, short data[64], huffman *hdc, huffman *hac, int b) -{ - int diff,dc,k; - int t = decode(j, hdc); - if (t < 0) return e("bad huffman code","Corrupt JPEG"); - - // 0 all the ac values now so we can do it 32-bits at a time - memset(data,0,64*sizeof(data[0])); - - diff = t ? extend_receive(j, t) : 0; - dc = j->img_comp[b].dc_pred + diff; - j->img_comp[b].dc_pred = dc; - data[0] = (short) dc; - - // decode AC components, see JPEG spec - k = 1; - do { - int r,s; - int rs = decode(j, hac); - if (rs < 0) return e("bad huffman code","Corrupt JPEG"); - s = rs & 15; - r = rs >> 4; - if (s == 0) { - if (rs != 0xf0) break; // end block - k += 16; - } else { - k += r; - // decode into unzigzag'd location - data[dezigzag[k++]] = (short) extend_receive(j,s); - } - } while (k < 64); - return 1; -} - -// take a -128..127 value and clamp it and convert to 0..255 -stbi_inline static uint8 clamp(int x) -{ - // trick to use a single test to catch both cases - if ((unsigned int) x > 255) { - if (x < 0) return 0; - if (x > 255) return 255; - } - return (uint8) x; -} - -#define f2f(x) (int) (((x) * 4096 + 0.5)) -#define fsh(x) ((x) << 12) - -// derived from jidctint -- DCT_ISLOW -#define IDCT_1D(s0,s1,s2,s3,s4,s5,s6,s7) \ - int t0,t1,t2,t3,p1,p2,p3,p4,p5,x0,x1,x2,x3; \ - p2 = s2; \ - p3 = s6; \ - p1 = (p2+p3) * f2f(0.5411961f); \ - t2 = p1 + p3*f2f(-1.847759065f); \ - t3 = p1 + p2*f2f( 0.765366865f); \ - p2 = s0; \ - p3 = s4; \ - t0 = fsh(p2+p3); \ - t1 = fsh(p2-p3); \ - x0 = t0+t3; \ - x3 = t0-t3; \ - x1 = t1+t2; \ - x2 = t1-t2; \ - t0 = s7; \ - t1 = s5; \ - t2 = s3; \ - t3 = s1; \ - p3 = t0+t2; \ - p4 = t1+t3; \ - p1 = t0+t3; \ - p2 = t1+t2; \ - p5 = (p3+p4)*f2f( 1.175875602f); \ - t0 = t0*f2f( 0.298631336f); \ - t1 = t1*f2f( 2.053119869f); \ - t2 = t2*f2f( 3.072711026f); \ - t3 = t3*f2f( 1.501321110f); \ - p1 = p5 + p1*f2f(-0.899976223f); \ - p2 = p5 + p2*f2f(-2.562915447f); \ - p3 = p3*f2f(-1.961570560f); \ - p4 = p4*f2f(-0.390180644f); \ - t3 += p1+p4; \ - t2 += p2+p3; \ - t1 += p2+p4; \ - t0 += p1+p3; - -#ifdef STBI_SIMD -typedef unsigned short stbi_dequantize_t; -#else -typedef uint8 stbi_dequantize_t; -#endif - -// .344 seconds on 3*anemones.jpg -static void idct_block(uint8 *out, int out_stride, short data[64], stbi_dequantize_t *dequantize) -{ - int i,val[64],*v=val; - stbi_dequantize_t *dq = dequantize; - uint8 *o; - short *d = data; - - // columns - for (i=0; i < 8; ++i,++d,++dq, ++v) { - // if all zeroes, shortcut -- this avoids dequantizing 0s and IDCTing - if (d[ 8]==0 && d[16]==0 && d[24]==0 && d[32]==0 - && d[40]==0 && d[48]==0 && d[56]==0) { - // no shortcut 0 seconds - // (1|2|3|4|5|6|7)==0 0 seconds - // all separate -0.047 seconds - // 1 && 2|3 && 4|5 && 6|7: -0.047 seconds - int dcterm = d[0] * dq[0] << 2; - v[0] = v[8] = v[16] = v[24] = v[32] = v[40] = v[48] = v[56] = dcterm; - } else { - IDCT_1D(d[ 0]*dq[ 0],d[ 8]*dq[ 8],d[16]*dq[16],d[24]*dq[24], - d[32]*dq[32],d[40]*dq[40],d[48]*dq[48],d[56]*dq[56]) - // constants scaled things up by 1<<12; let's bring them back - // down, but keep 2 extra bits of precision - x0 += 512; x1 += 512; x2 += 512; x3 += 512; - v[ 0] = (x0+t3) >> 10; - v[56] = (x0-t3) >> 10; - v[ 8] = (x1+t2) >> 10; - v[48] = (x1-t2) >> 10; - v[16] = (x2+t1) >> 10; - v[40] = (x2-t1) >> 10; - v[24] = (x3+t0) >> 10; - v[32] = (x3-t0) >> 10; - } - } - - for (i=0, v=val, o=out; i < 8; ++i,v+=8,o+=out_stride) { - // no fast case since the first 1D IDCT spread components out - IDCT_1D(v[0],v[1],v[2],v[3],v[4],v[5],v[6],v[7]) - // constants scaled things up by 1<<12, plus we had 1<<2 from first - // loop, plus horizontal and vertical each scale by sqrt(8) so together - // we've got an extra 1<<3, so 1<<17 total we need to remove. - // so we want to round that, which means adding 0.5 * 1<<17, - // aka 65536. Also, we'll end up with -128 to 127 that we want - // to encode as 0..255 by adding 128, so we'll add that before the shift - x0 += 65536 + (128<<17); - x1 += 65536 + (128<<17); - x2 += 65536 + (128<<17); - x3 += 65536 + (128<<17); - // tried computing the shifts into temps, or'ing the temps to see - // if any were out of range, but that was slower - o[0] = clamp((x0+t3) >> 17); - o[7] = clamp((x0-t3) >> 17); - o[1] = clamp((x1+t2) >> 17); - o[6] = clamp((x1-t2) >> 17); - o[2] = clamp((x2+t1) >> 17); - o[5] = clamp((x2-t1) >> 17); - o[3] = clamp((x3+t0) >> 17); - o[4] = clamp((x3-t0) >> 17); - } -} - -#ifdef STBI_SIMD -static stbi_idct_8x8 stbi_idct_installed = idct_block; - -void stbi_install_idct(stbi_idct_8x8 func) -{ - stbi_idct_installed = func; -} -#endif - -#define MARKER_none 0xff -// if there's a pending marker from the entropy stream, return that -// otherwise, fetch from the stream and get a marker. if there's no -// marker, return 0xff, which is never a valid marker value -static uint8 get_marker(jpeg *j) -{ - uint8 x; - if (j->marker != MARKER_none) { x = j->marker; j->marker = MARKER_none; return x; } - x = get8u(j->s); - if (x != 0xff) return MARKER_none; - while (x == 0xff) - x = get8u(j->s); - return x; -} - -// in each scan, we'll have scan_n components, and the order -// of the components is specified by order[] -#define RESTART(x) ((x) >= 0xd0 && (x) <= 0xd7) - -// after a restart interval, reset the entropy decoder and -// the dc prediction -static void reset(jpeg *j) -{ - j->code_bits = 0; - j->code_buffer = 0; - j->nomore = 0; - j->img_comp[0].dc_pred = j->img_comp[1].dc_pred = j->img_comp[2].dc_pred = 0; - j->marker = MARKER_none; - j->todo = j->restart_interval ? j->restart_interval : 0x7fffffff; - // no more than 1<<31 MCUs if no restart_interal? that's plenty safe, - // since we don't even allow 1<<30 pixels -} - -static int parse_entropy_coded_data(jpeg *z) -{ - reset(z); - if (z->scan_n == 1) { - int i,j; - #ifdef STBI_SIMD - __declspec(align(16)) - #endif - short data[64]; - int n = z->order[0]; - // non-interleaved data, we just need to process one block at a time, - // in trivial scanline order - // number of blocks to do just depends on how many actual "pixels" this - // component has, independent of interleaved MCU blocking and such - int w = (z->img_comp[n].x+7) >> 3; - int h = (z->img_comp[n].y+7) >> 3; - for (j=0; j < h; ++j) { - for (i=0; i < w; ++i) { - if (!decode_block(z, data, z->huff_dc+z->img_comp[n].hd, z->huff_ac+z->img_comp[n].ha, n)) return 0; - #ifdef STBI_SIMD - stbi_idct_installed(z->img_comp[n].data+z->img_comp[n].w2*j*8+i*8, z->img_comp[n].w2, data, z->dequant2[z->img_comp[n].tq]); - #else - idct_block(z->img_comp[n].data+z->img_comp[n].w2*j*8+i*8, z->img_comp[n].w2, data, z->dequant[z->img_comp[n].tq]); - #endif - // every data block is an MCU, so countdown the restart interval - if (--z->todo <= 0) { - if (z->code_bits < 24) grow_buffer_unsafe(z); - // if it's NOT a restart, then just bail, so we get corrupt data - // rather than no data - if (!RESTART(z->marker)) return 1; - reset(z); - } - } - } - } else { // interleaved! - int i,j,k,x,y; - short data[64]; - for (j=0; j < z->img_mcu_y; ++j) { - for (i=0; i < z->img_mcu_x; ++i) { - // scan an interleaved mcu... process scan_n components in order - for (k=0; k < z->scan_n; ++k) { - int n = z->order[k]; - // scan out an mcu's worth of this component; that's just determined - // by the basic H and V specified for the component - for (y=0; y < z->img_comp[n].v; ++y) { - for (x=0; x < z->img_comp[n].h; ++x) { - int x2 = (i*z->img_comp[n].h + x)*8; - int y2 = (j*z->img_comp[n].v + y)*8; - if (!decode_block(z, data, z->huff_dc+z->img_comp[n].hd, z->huff_ac+z->img_comp[n].ha, n)) return 0; - #ifdef STBI_SIMD - stbi_idct_installed(z->img_comp[n].data+z->img_comp[n].w2*y2+x2, z->img_comp[n].w2, data, z->dequant2[z->img_comp[n].tq]); - #else - idct_block(z->img_comp[n].data+z->img_comp[n].w2*y2+x2, z->img_comp[n].w2, data, z->dequant[z->img_comp[n].tq]); - #endif - } - } - } - // after all interleaved components, that's an interleaved MCU, - // so now count down the restart interval - if (--z->todo <= 0) { - if (z->code_bits < 24) grow_buffer_unsafe(z); - // if it's NOT a restart, then just bail, so we get corrupt data - // rather than no data - if (!RESTART(z->marker)) return 1; - reset(z); - } - } - } - } - return 1; -} - -static int process_marker(jpeg *z, int m) -{ - int L; - switch (m) { - case MARKER_none: // no marker found - return e("expected marker","Corrupt JPEG"); - - case 0xC2: // SOF - progressive - return e("progressive jpeg","JPEG format not supported (progressive)"); - - case 0xDD: // DRI - specify restart interval - if (get16(z->s) != 4) return e("bad DRI len","Corrupt JPEG"); - z->restart_interval = get16(z->s); - return 1; - - case 0xDB: // DQT - define quantization table - L = get16(z->s)-2; - while (L > 0) { - int q = get8(z->s); - int p = q >> 4; - int t = q & 15,i; - if (p != 0) return e("bad DQT type","Corrupt JPEG"); - if (t > 3) return e("bad DQT table","Corrupt JPEG"); - for (i=0; i < 64; ++i) - z->dequant[t][dezigzag[i]] = get8u(z->s); - #ifdef STBI_SIMD - for (i=0; i < 64; ++i) - z->dequant2[t][i] = z->dequant[t][i]; - #endif - L -= 65; - } - return L==0; - - case 0xC4: // DHT - define huffman table - L = get16(z->s)-2; - while (L > 0) { - uint8 *v; - int sizes[16],i,m=0; - int q = get8(z->s); - int tc = q >> 4; - int th = q & 15; - if (tc > 1 || th > 3) return e("bad DHT header","Corrupt JPEG"); - for (i=0; i < 16; ++i) { - sizes[i] = get8(z->s); - m += sizes[i]; - } - L -= 17; - if (tc == 0) { - if (!build_huffman(z->huff_dc+th, sizes)) return 0; - v = z->huff_dc[th].values; - } else { - if (!build_huffman(z->huff_ac+th, sizes)) return 0; - v = z->huff_ac[th].values; - } - for (i=0; i < m; ++i) - v[i] = get8u(z->s); - L -= m; - } - return L==0; - } - // check for comment block or APP blocks - if ((m >= 0xE0 && m <= 0xEF) || m == 0xFE) { - skip(z->s, get16(z->s)-2); - return 1; - } - return 0; -} - -// after we see SOS -static int process_scan_header(jpeg *z) -{ - int i; - int Ls = get16(z->s); - z->scan_n = get8(z->s); - if (z->scan_n < 1 || z->scan_n > 4 || z->scan_n > (int) z->s->img_n) return e("bad SOS component count","Corrupt JPEG"); - if (Ls != 6+2*z->scan_n) return e("bad SOS len","Corrupt JPEG"); - for (i=0; i < z->scan_n; ++i) { - int id = get8(z->s), which; - int q = get8(z->s); - for (which = 0; which < z->s->img_n; ++which) - if (z->img_comp[which].id == id) - break; - if (which == z->s->img_n) return 0; - z->img_comp[which].hd = q >> 4; if (z->img_comp[which].hd > 3) return e("bad DC huff","Corrupt JPEG"); - z->img_comp[which].ha = q & 15; if (z->img_comp[which].ha > 3) return e("bad AC huff","Corrupt JPEG"); - z->order[i] = which; - } - if (get8(z->s) != 0) return e("bad SOS","Corrupt JPEG"); - get8(z->s); // should be 63, but might be 0 - if (get8(z->s) != 0) return e("bad SOS","Corrupt JPEG"); - - return 1; -} - -static int process_frame_header(jpeg *z, int scan) -{ - stbi *s = z->s; - int Lf,p,i,q, h_max=1,v_max=1,c; - Lf = get16(s); if (Lf < 11) return e("bad SOF len","Corrupt JPEG"); // JPEG - p = get8(s); if (p != 8) return e("only 8-bit","JPEG format not supported: 8-bit only"); // JPEG baseline - s->img_y = get16(s); if (s->img_y == 0) return e("no header height", "JPEG format not supported: delayed height"); // Legal, but we don't handle it--but neither does IJG - s->img_x = get16(s); if (s->img_x == 0) return e("0 width","Corrupt JPEG"); // JPEG requires - c = get8(s); - if (c != 3 && c != 1) return e("bad component count","Corrupt JPEG"); // JFIF requires - s->img_n = c; - for (i=0; i < c; ++i) { - z->img_comp[i].data = NULL; - z->img_comp[i].linebuf = NULL; - } - - if (Lf != 8+3*s->img_n) return e("bad SOF len","Corrupt JPEG"); - - for (i=0; i < s->img_n; ++i) { - z->img_comp[i].id = get8(s); - if (z->img_comp[i].id != i+1) // JFIF requires - if (z->img_comp[i].id != i) // some version of jpegtran outputs non-JFIF-compliant files! - return e("bad component ID","Corrupt JPEG"); - q = get8(s); - z->img_comp[i].h = (q >> 4); if (!z->img_comp[i].h || z->img_comp[i].h > 4) return e("bad H","Corrupt JPEG"); - z->img_comp[i].v = q & 15; if (!z->img_comp[i].v || z->img_comp[i].v > 4) return e("bad V","Corrupt JPEG"); - z->img_comp[i].tq = get8(s); if (z->img_comp[i].tq > 3) return e("bad TQ","Corrupt JPEG"); - } - - if (scan != SCAN_load) return 1; - - if ((1 << 30) / s->img_x / s->img_n < s->img_y) return e("too large", "Image too large to decode"); - - for (i=0; i < s->img_n; ++i) { - if (z->img_comp[i].h > h_max) h_max = z->img_comp[i].h; - if (z->img_comp[i].v > v_max) v_max = z->img_comp[i].v; - } - - // compute interleaved mcu info - z->img_h_max = h_max; - z->img_v_max = v_max; - z->img_mcu_w = h_max * 8; - z->img_mcu_h = v_max * 8; - z->img_mcu_x = (s->img_x + z->img_mcu_w-1) / z->img_mcu_w; - z->img_mcu_y = (s->img_y + z->img_mcu_h-1) / z->img_mcu_h; - - for (i=0; i < s->img_n; ++i) { - // number of effective pixels (e.g. for non-interleaved MCU) - z->img_comp[i].x = (s->img_x * z->img_comp[i].h + h_max-1) / h_max; - z->img_comp[i].y = (s->img_y * z->img_comp[i].v + v_max-1) / v_max; - // to simplify generation, we'll allocate enough memory to decode - // the bogus oversized data from using interleaved MCUs and their - // big blocks (e.g. a 16x16 iMCU on an image of width 33); we won't - // discard the extra data until colorspace conversion - z->img_comp[i].w2 = z->img_mcu_x * z->img_comp[i].h * 8; - z->img_comp[i].h2 = z->img_mcu_y * z->img_comp[i].v * 8; - z->img_comp[i].raw_data = malloc(z->img_comp[i].w2 * z->img_comp[i].h2+15); - if (z->img_comp[i].raw_data == NULL) { - for(--i; i >= 0; --i) { - free(z->img_comp[i].raw_data); - z->img_comp[i].data = NULL; - } - return e("outofmem", "Out of memory"); - } - // align blocks for installable-idct using mmx/sse - z->img_comp[i].data = (uint8*) (((size_t) z->img_comp[i].raw_data + 15) & ~15); - z->img_comp[i].linebuf = NULL; - } - - return 1; -} - -// use comparisons since in some cases we handle more than one case (e.g. SOF) -#define DNL(x) ((x) == 0xdc) -#define SOI(x) ((x) == 0xd8) -#define EOI(x) ((x) == 0xd9) -#define SOF(x) ((x) == 0xc0 || (x) == 0xc1) -#define SOS(x) ((x) == 0xda) - -static int decode_jpeg_header(jpeg *z, int scan) -{ - int m; - z->marker = MARKER_none; // initialize cached marker to empty - m = get_marker(z); - if (!SOI(m)) return e("no SOI","Corrupt JPEG"); - if (scan == SCAN_type) return 1; - m = get_marker(z); - while (!SOF(m)) { - if (!process_marker(z,m)) return 0; - m = get_marker(z); - while (m == MARKER_none) { - // some files have extra padding after their blocks, so ok, we'll scan - if (at_eof(z->s)) return e("no SOF", "Corrupt JPEG"); - m = get_marker(z); - } - } - if (!process_frame_header(z, scan)) return 0; - return 1; -} - -static int decode_jpeg_image(jpeg *j) -{ - int m; - j->restart_interval = 0; - if (!decode_jpeg_header(j, SCAN_load)) return 0; - m = get_marker(j); - while (!EOI(m)) { - if (SOS(m)) { - if (!process_scan_header(j)) return 0; - if (!parse_entropy_coded_data(j)) return 0; - if (j->marker == MARKER_none ) { - // handle 0s at the end of image data from IP Kamera 9060 - while (!at_eof(j->s)) { - int x = get8(j->s); - if (x == 255) { - j->marker = get8u(j->s); - break; - } else if (x != 0) { - return 0; - } - } - // if we reach eof without hitting a marker, get_marker() below will fail and we'll eventually return 0 - } - } else { - if (!process_marker(j, m)) return 0; - } - m = get_marker(j); - } - return 1; -} - -// static jfif-centered resampling (across block boundaries) - -typedef uint8 *(*resample_row_func)(uint8 *out, uint8 *in0, uint8 *in1, - int w, int hs); - -#define div4(x) ((uint8) ((x) >> 2)) - -static uint8 *resample_row_1(uint8 *out, uint8 *in_near, uint8 *in_far, int w, int hs) -{ - STBI_NOTUSED(out); - STBI_NOTUSED(in_far); - STBI_NOTUSED(w); - STBI_NOTUSED(hs); - return in_near; -} - -static uint8* resample_row_v_2(uint8 *out, uint8 *in_near, uint8 *in_far, int w, int hs) -{ - // need to generate two samples vertically for every one in input - int i; - STBI_NOTUSED(hs); - for (i=0; i < w; ++i) - out[i] = div4(3*in_near[i] + in_far[i] + 2); - return out; -} - -static uint8* resample_row_h_2(uint8 *out, uint8 *in_near, uint8 *in_far, int w, int hs) -{ - // need to generate two samples horizontally for every one in input - int i; - uint8 *input = in_near; - - if (w == 1) { - // if only one sample, can't do any interpolation - out[0] = out[1] = input[0]; - return out; - } - - out[0] = input[0]; - out[1] = div4(input[0]*3 + input[1] + 2); - for (i=1; i < w-1; ++i) { - int n = 3*input[i]+2; - out[i*2+0] = div4(n+input[i-1]); - out[i*2+1] = div4(n+input[i+1]); - } - out[i*2+0] = div4(input[w-2]*3 + input[w-1] + 2); - out[i*2+1] = input[w-1]; - - STBI_NOTUSED(in_far); - STBI_NOTUSED(hs); - - return out; -} - -#define div16(x) ((uint8) ((x) >> 4)) - -static uint8 *resample_row_hv_2(uint8 *out, uint8 *in_near, uint8 *in_far, int w, int hs) -{ - // need to generate 2x2 samples for every one in input - int i,t0,t1; - if (w == 1) { - out[0] = out[1] = div4(3*in_near[0] + in_far[0] + 2); - return out; - } - - t1 = 3*in_near[0] + in_far[0]; - out[0] = div4(t1+2); - for (i=1; i < w; ++i) { - t0 = t1; - t1 = 3*in_near[i]+in_far[i]; - out[i*2-1] = div16(3*t0 + t1 + 8); - out[i*2 ] = div16(3*t1 + t0 + 8); - } - out[w*2-1] = div4(t1+2); - - STBI_NOTUSED(hs); - - return out; -} - -static uint8 *resample_row_generic(uint8 *out, uint8 *in_near, uint8 *in_far, int w, int hs) -{ - // resample with nearest-neighbor - int i,j; - STBI_NOTUSED(in_far); - for (i=0; i < w; ++i) - for (j=0; j < hs; ++j) - out[i*hs+j] = in_near[i]; - return out; -} - -#define float2fixed(x) ((int) ((x) * 65536 + 0.5)) - -// 0.38 seconds on 3*anemones.jpg (0.25 with processor = Pro) -// VC6 without processor=Pro is generating multiple LEAs per multiply! -static void YCbCr_to_RGB_row(uint8 *out, const uint8 *y, const uint8 *pcb, const uint8 *pcr, int count, int step) -{ - int i; - for (i=0; i < count; ++i) { - int y_fixed = (y[i] << 16) + 32768; // rounding - int r,g,b; - int cr = pcr[i] - 128; - int cb = pcb[i] - 128; - r = y_fixed + cr*float2fixed(1.40200f); - g = y_fixed - cr*float2fixed(0.71414f) - cb*float2fixed(0.34414f); - b = y_fixed + cb*float2fixed(1.77200f); - r >>= 16; - g >>= 16; - b >>= 16; - if ((unsigned) r > 255) { if (r < 0) r = 0; else r = 255; } - if ((unsigned) g > 255) { if (g < 0) g = 0; else g = 255; } - if ((unsigned) b > 255) { if (b < 0) b = 0; else b = 255; } - out[0] = (uint8)r; - out[1] = (uint8)g; - out[2] = (uint8)b; - out[3] = 255; - out += step; - } -} - -#ifdef STBI_SIMD -static stbi_YCbCr_to_RGB_run stbi_YCbCr_installed = YCbCr_to_RGB_row; - -void stbi_install_YCbCr_to_RGB(stbi_YCbCr_to_RGB_run func) -{ - stbi_YCbCr_installed = func; -} -#endif - - -// clean up the temporary component buffers -static void cleanup_jpeg(jpeg *j) -{ - int i; - for (i=0; i < j->s->img_n; ++i) { - if (j->img_comp[i].data) { - free(j->img_comp[i].raw_data); - j->img_comp[i].data = NULL; - } - if (j->img_comp[i].linebuf) { - free(j->img_comp[i].linebuf); - j->img_comp[i].linebuf = NULL; - } - } -} - -typedef struct -{ - resample_row_func resample; - uint8 *line0,*line1; - int hs,vs; // expansion factor in each axis - int w_lores; // horizontal pixels pre-expansion - int ystep; // how far through vertical expansion we are - int ypos; // which pre-expansion row we're on -} stbi_resample; - -static uint8 *load_jpeg_image(jpeg *z, int *out_x, int *out_y, int *comp, int req_comp) -{ - int n, decode_n; - // validate req_comp - if (req_comp < 0 || req_comp > 4) return epuc("bad req_comp", "Internal error"); - z->s->img_n = 0; - - // load a jpeg image from whichever source - if (!decode_jpeg_image(z)) { cleanup_jpeg(z); return NULL; } - - // determine actual number of components to generate - n = req_comp ? req_comp : z->s->img_n; - - if (z->s->img_n == 3 && n < 3) - decode_n = 1; - else - decode_n = z->s->img_n; - - // resample and color-convert - { - int k; - uint i,j; - uint8 *output; - uint8 *coutput[4]; - - stbi_resample res_comp[4]; - - for (k=0; k < decode_n; ++k) { - stbi_resample *r = &res_comp[k]; - - // allocate line buffer big enough for upsampling off the edges - // with upsample factor of 4 - z->img_comp[k].linebuf = (uint8 *) malloc(z->s->img_x + 3); - if (!z->img_comp[k].linebuf) { cleanup_jpeg(z); return epuc("outofmem", "Out of memory"); } - - r->hs = z->img_h_max / z->img_comp[k].h; - r->vs = z->img_v_max / z->img_comp[k].v; - r->ystep = r->vs >> 1; - r->w_lores = (z->s->img_x + r->hs-1) / r->hs; - r->ypos = 0; - r->line0 = r->line1 = z->img_comp[k].data; - - if (r->hs == 1 && r->vs == 1) r->resample = resample_row_1; - else if (r->hs == 1 && r->vs == 2) r->resample = resample_row_v_2; - else if (r->hs == 2 && r->vs == 1) r->resample = resample_row_h_2; - else if (r->hs == 2 && r->vs == 2) r->resample = resample_row_hv_2; - else r->resample = resample_row_generic; - } - - // can't error after this so, this is safe - output = (uint8 *) malloc(n * z->s->img_x * z->s->img_y + 1); - if (!output) { cleanup_jpeg(z); return epuc("outofmem", "Out of memory"); } - - // now go ahead and resample - for (j=0; j < z->s->img_y; ++j) { - uint8 *out = output + n * z->s->img_x * j; - for (k=0; k < decode_n; ++k) { - stbi_resample *r = &res_comp[k]; - int y_bot = r->ystep >= (r->vs >> 1); - coutput[k] = r->resample(z->img_comp[k].linebuf, - y_bot ? r->line1 : r->line0, - y_bot ? r->line0 : r->line1, - r->w_lores, r->hs); - if (++r->ystep >= r->vs) { - r->ystep = 0; - r->line0 = r->line1; - if (++r->ypos < z->img_comp[k].y) - r->line1 += z->img_comp[k].w2; - } - } - if (n >= 3) { - uint8 *y = coutput[0]; - if (z->s->img_n == 3) { - #ifdef STBI_SIMD - stbi_YCbCr_installed(out, y, coutput[1], coutput[2], z->s.img_x, n); - #else - YCbCr_to_RGB_row(out, y, coutput[1], coutput[2], z->s->img_x, n); - #endif - } else - for (i=0; i < z->s->img_x; ++i) { - out[0] = out[1] = out[2] = y[i]; - out[3] = 255; // not used if n==3 - out += n; - } - } else { - uint8 *y = coutput[0]; - if (n == 1) - for (i=0; i < z->s->img_x; ++i) out[i] = y[i]; - else - for (i=0; i < z->s->img_x; ++i) *out++ = y[i], *out++ = 255; - } - } - cleanup_jpeg(z); - *out_x = z->s->img_x; - *out_y = z->s->img_y; - if (comp) *comp = z->s->img_n; // report original components, not output - return output; - } -} - -static unsigned char *stbi_jpeg_load(stbi *s, int *x, int *y, int *comp, int req_comp) -{ - jpeg j; - j.s = s; - return load_jpeg_image(&j, x,y,comp,req_comp); -} - -static int stbi_jpeg_test(stbi *s) -{ - int r; - jpeg j; - j.s = s; - r = decode_jpeg_header(&j, SCAN_type); - stbi_rewind(s); - return r; -} - -static int stbi_jpeg_info_raw(jpeg *j, int *x, int *y, int *comp) -{ - if (!decode_jpeg_header(j, SCAN_header)) { - stbi_rewind( j->s ); - return 0; - } - if (x) *x = j->s->img_x; - if (y) *y = j->s->img_y; - if (comp) *comp = j->s->img_n; - return 1; -} - -static int stbi_jpeg_info(stbi *s, int *x, int *y, int *comp) -{ - jpeg j; - j.s = s; - return stbi_jpeg_info_raw(&j, x, y, comp); -} - -// public domain zlib decode v0.2 Sean Barrett 2006-11-18 -// simple implementation -// - all input must be provided in an upfront buffer -// - all output is written to a single output buffer (can malloc/realloc) -// performance -// - fast huffman - -// fast-way is faster to check than jpeg huffman, but slow way is slower -#define ZFAST_BITS 9 // accelerate all cases in default tables -#define ZFAST_MASK ((1 << ZFAST_BITS) - 1) - -// zlib-style huffman encoding -// (jpegs packs from left, zlib from right, so can't share code) -typedef struct -{ - uint16 fast[1 << ZFAST_BITS]; - uint16 firstcode[16]; - int maxcode[17]; - uint16 firstsymbol[16]; - uint8 size[288]; - uint16 value[288]; -} zhuffman; - -stbi_inline static int bitreverse16(int n) -{ - n = ((n & 0xAAAA) >> 1) | ((n & 0x5555) << 1); - n = ((n & 0xCCCC) >> 2) | ((n & 0x3333) << 2); - n = ((n & 0xF0F0) >> 4) | ((n & 0x0F0F) << 4); - n = ((n & 0xFF00) >> 8) | ((n & 0x00FF) << 8); - return n; -} - -stbi_inline static int bit_reverse(int v, int bits) -{ - assert(bits <= 16); - // to bit reverse n bits, reverse 16 and shift - // e.g. 11 bits, bit reverse and shift away 5 - return bitreverse16(v) >> (16-bits); -} - -static int zbuild_huffman(zhuffman *z, uint8 *sizelist, int num) -{ - int i,k=0; - int code, next_code[16], sizes[17]; - - // DEFLATE spec for generating codes - memset(sizes, 0, sizeof(sizes)); - memset(z->fast, 255, sizeof(z->fast)); - for (i=0; i < num; ++i) - ++sizes[sizelist[i]]; - sizes[0] = 0; - for (i=1; i < 16; ++i) - assert(sizes[i] <= (1 << i)); - code = 0; - for (i=1; i < 16; ++i) { - next_code[i] = code; - z->firstcode[i] = (uint16) code; - z->firstsymbol[i] = (uint16) k; - code = (code + sizes[i]); - if (sizes[i]) - if (code-1 >= (1 << i)) return e("bad codelengths","Corrupt JPEG"); - z->maxcode[i] = code << (16-i); // preshift for inner loop - code <<= 1; - k += sizes[i]; - } - z->maxcode[16] = 0x10000; // sentinel - for (i=0; i < num; ++i) { - int s = sizelist[i]; - if (s) { - int c = next_code[s] - z->firstcode[s] + z->firstsymbol[s]; - z->size[c] = (uint8)s; - z->value[c] = (uint16)i; - if (s <= ZFAST_BITS) { - int k = bit_reverse(next_code[s],s); - while (k < (1 << ZFAST_BITS)) { - z->fast[k] = (uint16) c; - k += (1 << s); - } - } - ++next_code[s]; - } - } - return 1; -} - -// zlib-from-memory implementation for PNG reading -// because PNG allows splitting the zlib stream arbitrarily, -// and it's annoying structurally to have PNG call ZLIB call PNG, -// we require PNG read all the IDATs and combine them into a single -// memory buffer - -typedef struct -{ - uint8 *zbuffer, *zbuffer_end; - int num_bits; - uint32 code_buffer; - - char *zout; - char *zout_start; - char *zout_end; - int z_expandable; - - zhuffman z_length, z_distance; -} zbuf; - -stbi_inline static int zget8(zbuf *z) -{ - if (z->zbuffer >= z->zbuffer_end) return 0; - return *z->zbuffer++; -} - -static void fill_bits(zbuf *z) -{ - do { - assert(z->code_buffer < (1U << z->num_bits)); - z->code_buffer |= zget8(z) << z->num_bits; - z->num_bits += 8; - } while (z->num_bits <= 24); -} - -stbi_inline static unsigned int zreceive(zbuf *z, int n) -{ - unsigned int k; - if (z->num_bits < n) fill_bits(z); - k = z->code_buffer & ((1 << n) - 1); - z->code_buffer >>= n; - z->num_bits -= n; - return k; -} - -stbi_inline static int zhuffman_decode(zbuf *a, zhuffman *z) -{ - int b,s,k; - if (a->num_bits < 16) fill_bits(a); - b = z->fast[a->code_buffer & ZFAST_MASK]; - if (b < 0xffff) { - s = z->size[b]; - a->code_buffer >>= s; - a->num_bits -= s; - return z->value[b]; - } - - // not resolved by fast table, so compute it the slow way - // use jpeg approach, which requires MSbits at top - k = bit_reverse(a->code_buffer, 16); - for (s=ZFAST_BITS+1; ; ++s) - if (k < z->maxcode[s]) - break; - if (s == 16) return -1; // invalid code! - // code size is s, so: - b = (k >> (16-s)) - z->firstcode[s] + z->firstsymbol[s]; - assert(z->size[b] == s); - a->code_buffer >>= s; - a->num_bits -= s; - return z->value[b]; -} - -static int expand(zbuf *z, int n) // need to make room for n bytes -{ - char *q; - int cur, limit; - if (!z->z_expandable) return e("output buffer limit","Corrupt PNG"); - cur = (int) (z->zout - z->zout_start); - limit = (int) (z->zout_end - z->zout_start); - while (cur + n > limit) - limit *= 2; - q = (char *) realloc(z->zout_start, limit); - if (q == NULL) return e("outofmem", "Out of memory"); - z->zout_start = q; - z->zout = q + cur; - z->zout_end = q + limit; - return 1; -} - -static int length_base[31] = { - 3,4,5,6,7,8,9,10,11,13, - 15,17,19,23,27,31,35,43,51,59, - 67,83,99,115,131,163,195,227,258,0,0 }; - -static int length_extra[31]= -{ 0,0,0,0,0,0,0,0,1,1,1,1,2,2,2,2,3,3,3,3,4,4,4,4,5,5,5,5,0,0,0 }; - -static int dist_base[32] = { 1,2,3,4,5,7,9,13,17,25,33,49,65,97,129,193, -257,385,513,769,1025,1537,2049,3073,4097,6145,8193,12289,16385,24577,0,0}; - -static int dist_extra[32] = -{ 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}; - -static int parse_huffman_block(zbuf *a) -{ - for(;;) { - int z = zhuffman_decode(a, &a->z_length); - if (z < 256) { - if (z < 0) return e("bad huffman code","Corrupt PNG"); // error in huffman codes - if (a->zout >= a->zout_end) if (!expand(a, 1)) return 0; - *a->zout++ = (char) z; - } else { - uint8 *p; - int len,dist; - if (z == 256) return 1; - z -= 257; - len = length_base[z]; - if (length_extra[z]) len += zreceive(a, length_extra[z]); - z = zhuffman_decode(a, &a->z_distance); - if (z < 0) return e("bad huffman code","Corrupt PNG"); - dist = dist_base[z]; - if (dist_extra[z]) dist += zreceive(a, dist_extra[z]); - if (a->zout - a->zout_start < dist) return e("bad dist","Corrupt PNG"); - if (a->zout + len > a->zout_end) if (!expand(a, len)) return 0; - p = (uint8 *) (a->zout - dist); - while (len--) - *a->zout++ = *p++; - } - } -} - -static int compute_huffman_codes(zbuf *a) -{ - static uint8 length_dezigzag[19] = { 16,17,18,0,8,7,9,6,10,5,11,4,12,3,13,2,14,1,15 }; - zhuffman z_codelength; - uint8 lencodes[286+32+137];//padding for maximum single op - uint8 codelength_sizes[19]; - int i,n; - - int hlit = zreceive(a,5) + 257; - int hdist = zreceive(a,5) + 1; - int hclen = zreceive(a,4) + 4; - - memset(codelength_sizes, 0, sizeof(codelength_sizes)); - for (i=0; i < hclen; ++i) { - int s = zreceive(a,3); - codelength_sizes[length_dezigzag[i]] = (uint8) s; - } - if (!zbuild_huffman(&z_codelength, codelength_sizes, 19)) return 0; - - n = 0; - while (n < hlit + hdist) { - int c = zhuffman_decode(a, &z_codelength); - assert(c >= 0 && c < 19); - if (c < 16) - lencodes[n++] = (uint8) c; - else if (c == 16) { - c = zreceive(a,2)+3; - memset(lencodes+n, lencodes[n-1], c); - n += c; - } else if (c == 17) { - c = zreceive(a,3)+3; - memset(lencodes+n, 0, c); - n += c; - } else { - assert(c == 18); - c = zreceive(a,7)+11; - memset(lencodes+n, 0, c); - n += c; - } - } - if (n != hlit+hdist) return e("bad codelengths","Corrupt PNG"); - if (!zbuild_huffman(&a->z_length, lencodes, hlit)) return 0; - if (!zbuild_huffman(&a->z_distance, lencodes+hlit, hdist)) return 0; - return 1; -} - -static int parse_uncompressed_block(zbuf *a) -{ - uint8 header[4]; - int len,nlen,k; - if (a->num_bits & 7) - zreceive(a, a->num_bits & 7); // discard - // drain the bit-packed data into header - k = 0; - while (a->num_bits > 0) { - header[k++] = (uint8) (a->code_buffer & 255); // wtf this warns? - a->code_buffer >>= 8; - a->num_bits -= 8; - } - assert(a->num_bits == 0); - // now fill header the normal way - while (k < 4) - header[k++] = (uint8) zget8(a); - len = header[1] * 256 + header[0]; - nlen = header[3] * 256 + header[2]; - if (nlen != (len ^ 0xffff)) return e("zlib corrupt","Corrupt PNG"); - if (a->zbuffer + len > a->zbuffer_end) return e("read past buffer","Corrupt PNG"); - if (a->zout + len > a->zout_end) - if (!expand(a, len)) return 0; - memcpy(a->zout, a->zbuffer, len); - a->zbuffer += len; - a->zout += len; - return 1; -} - -static int parse_zlib_header(zbuf *a) -{ - int cmf = zget8(a); - int cm = cmf & 15; - /* int cinfo = cmf >> 4; */ - int flg = zget8(a); - if ((cmf*256+flg) % 31 != 0) return e("bad zlib header","Corrupt PNG"); // zlib spec - if (flg & 32) return e("no preset dict","Corrupt PNG"); // preset dictionary not allowed in png - if (cm != 8) return e("bad compression","Corrupt PNG"); // DEFLATE required for png - // window = 1 << (8 + cinfo)... but who cares, we fully buffer output - return 1; -} - -// @TODO: should statically initialize these for optimal thread safety -static uint8 default_length[288], default_distance[32]; -static void init_defaults(void) -{ - int i; // use <= to match clearly with spec - for (i=0; i <= 143; ++i) default_length[i] = 8; - for ( ; i <= 255; ++i) default_length[i] = 9; - for ( ; i <= 279; ++i) default_length[i] = 7; - for ( ; i <= 287; ++i) default_length[i] = 8; - - for (i=0; i <= 31; ++i) default_distance[i] = 5; -} - -int stbi_png_partial; // a quick hack to only allow decoding some of a PNG... I should implement real streaming support instead -static int parse_zlib(zbuf *a, int parse_header) -{ - int final, type; - if (parse_header) - if (!parse_zlib_header(a)) return 0; - a->num_bits = 0; - a->code_buffer = 0; - do { - final = zreceive(a,1); - type = zreceive(a,2); - if (type == 0) { - if (!parse_uncompressed_block(a)) return 0; - } else if (type == 3) { - return 0; - } else { - if (type == 1) { - // use fixed code lengths - if (!default_distance[31]) init_defaults(); - if (!zbuild_huffman(&a->z_length , default_length , 288)) return 0; - if (!zbuild_huffman(&a->z_distance, default_distance, 32)) return 0; - } else { - if (!compute_huffman_codes(a)) return 0; - } - if (!parse_huffman_block(a)) return 0; - } - if (stbi_png_partial && a->zout - a->zout_start > 65536) - break; - } while (!final); - return 1; -} - -static int do_zlib(zbuf *a, char *obuf, int olen, int exp, int parse_header) -{ - a->zout_start = obuf; - a->zout = obuf; - a->zout_end = obuf + olen; - a->z_expandable = exp; - - return parse_zlib(a, parse_header); -} - -char *stbi_zlib_decode_malloc_guesssize(const char *buffer, int len, int initial_size, int *outlen) -{ - zbuf a; - char *p = (char *) malloc(initial_size); - if (p == NULL) return NULL; - a.zbuffer = (uint8 *) buffer; - a.zbuffer_end = (uint8 *) buffer + len; - if (do_zlib(&a, p, initial_size, 1, 1)) { - if (outlen) *outlen = (int) (a.zout - a.zout_start); - return a.zout_start; - } else { - free(a.zout_start); - return NULL; - } -} - -char *stbi_zlib_decode_malloc(char const *buffer, int len, int *outlen) -{ - return stbi_zlib_decode_malloc_guesssize(buffer, len, 16384, outlen); -} - -char *stbi_zlib_decode_malloc_guesssize_headerflag(const char *buffer, int len, int initial_size, int *outlen, int parse_header) -{ - zbuf a; - char *p = (char *) malloc(initial_size); - if (p == NULL) return NULL; - a.zbuffer = (uint8 *) buffer; - a.zbuffer_end = (uint8 *) buffer + len; - if (do_zlib(&a, p, initial_size, 1, parse_header)) { - if (outlen) *outlen = (int) (a.zout - a.zout_start); - return a.zout_start; - } else { - free(a.zout_start); - return NULL; - } -} - -int stbi_zlib_decode_buffer(char *obuffer, int olen, char const *ibuffer, int ilen) -{ - zbuf a; - a.zbuffer = (uint8 *) ibuffer; - a.zbuffer_end = (uint8 *) ibuffer + ilen; - if (do_zlib(&a, obuffer, olen, 0, 1)) - return (int) (a.zout - a.zout_start); - else - return -1; -} - -char *stbi_zlib_decode_noheader_malloc(char const *buffer, int len, int *outlen) -{ - zbuf a; - char *p = (char *) malloc(16384); - if (p == NULL) return NULL; - a.zbuffer = (uint8 *) buffer; - a.zbuffer_end = (uint8 *) buffer+len; - if (do_zlib(&a, p, 16384, 1, 0)) { - if (outlen) *outlen = (int) (a.zout - a.zout_start); - return a.zout_start; - } else { - free(a.zout_start); - return NULL; - } -} - -int stbi_zlib_decode_noheader_buffer(char *obuffer, int olen, const char *ibuffer, int ilen) -{ - zbuf a; - a.zbuffer = (uint8 *) ibuffer; - a.zbuffer_end = (uint8 *) ibuffer + ilen; - if (do_zlib(&a, obuffer, olen, 0, 0)) - return (int) (a.zout - a.zout_start); - else - return -1; -} - -// public domain "baseline" PNG decoder v0.10 Sean Barrett 2006-11-18 -// simple implementation -// - only 8-bit samples -// - no CRC checking -// - allocates lots of intermediate memory -// - avoids problem of streaming data between subsystems -// - avoids explicit window management -// performance -// - uses stb_zlib, a PD zlib implementation with fast huffman decoding - - -typedef struct -{ - uint32 length; - uint32 type; -} chunk; - -#define PNG_TYPE(a,b,c,d) (((a) << 24) + ((b) << 16) + ((c) << 8) + (d)) - -static chunk get_chunk_header(stbi *s) -{ - chunk c; - c.length = get32(s); - c.type = get32(s); - return c; -} - -static int check_png_header(stbi *s) -{ - static uint8 png_sig[8] = { 137,80,78,71,13,10,26,10 }; - int i; - for (i=0; i < 8; ++i) - if (get8u(s) != png_sig[i]) return e("bad png sig","Not a PNG"); - return 1; -} - -typedef struct -{ - stbi *s; - uint8 *idata, *expanded, *out; -} png; - - -enum { - F_none=0, F_sub=1, F_up=2, F_avg=3, F_paeth=4, - F_avg_first, F_paeth_first -}; - -static uint8 first_row_filter[5] = -{ - F_none, F_sub, F_none, F_avg_first, F_paeth_first -}; - -static int paeth(int a, int b, int c) -{ - int p = a + b - c; - int pa = abs(p-a); - int pb = abs(p-b); - int pc = abs(p-c); - if (pa <= pb && pa <= pc) return a; - if (pb <= pc) return b; - return c; -} - -// create the png data from post-deflated data -static int create_png_image_raw(png *a, uint8 *raw, uint32 raw_len, int out_n, uint32 x, uint32 y) -{ - stbi *s = a->s; - uint32 i,j,stride = x*out_n; - int k; - int img_n = s->img_n; // copy it into a local for later - assert(out_n == s->img_n || out_n == s->img_n+1); - if (stbi_png_partial) y = 1; - a->out = (uint8 *) malloc(x * y * out_n); - if (!a->out) return e("outofmem", "Out of memory"); - if (!stbi_png_partial) { - if (s->img_x == x && s->img_y == y) { - if (raw_len != (img_n * x + 1) * y) return e("not enough pixels","Corrupt PNG"); - } else { // interlaced: - if (raw_len < (img_n * x + 1) * y) return e("not enough pixels","Corrupt PNG"); - } - } - for (j=0; j < y; ++j) { - uint8 *cur = a->out + stride*j; - uint8 *prior = cur - stride; - int filter = *raw++; - if (filter > 4) return e("invalid filter","Corrupt PNG"); - // if first row, use special filter that doesn't sample previous row - if (j == 0) filter = first_row_filter[filter]; - // handle first pixel explicitly - for (k=0; k < img_n; ++k) { - switch (filter) { - case F_none : cur[k] = raw[k]; break; - case F_sub : cur[k] = raw[k]; break; - case F_up : cur[k] = raw[k] + prior[k]; break; - case F_avg : cur[k] = raw[k] + (prior[k]>>1); break; - case F_paeth : cur[k] = (uint8) (raw[k] + paeth(0,prior[k],0)); break; - case F_avg_first : cur[k] = raw[k]; break; - case F_paeth_first: cur[k] = raw[k]; break; - } - } - if (img_n != out_n) cur[img_n] = 255; - raw += img_n; - cur += out_n; - prior += out_n; - // this is a little gross, so that we don't switch per-pixel or per-component - if (img_n == out_n) { - #define CASE(f) \ - case f: \ - for (i=x-1; i >= 1; --i, raw+=img_n,cur+=img_n,prior+=img_n) \ - for (k=0; k < img_n; ++k) - switch (filter) { - CASE(F_none) cur[k] = raw[k]; break; - CASE(F_sub) cur[k] = raw[k] + cur[k-img_n]; break; - CASE(F_up) cur[k] = raw[k] + prior[k]; break; - CASE(F_avg) cur[k] = raw[k] + ((prior[k] + cur[k-img_n])>>1); break; - CASE(F_paeth) cur[k] = (uint8) (raw[k] + paeth(cur[k-img_n],prior[k],prior[k-img_n])); break; - CASE(F_avg_first) cur[k] = raw[k] + (cur[k-img_n] >> 1); break; - CASE(F_paeth_first) cur[k] = (uint8) (raw[k] + paeth(cur[k-img_n],0,0)); break; - } - #undef CASE - } else { - assert(img_n+1 == out_n); - #define CASE(f) \ - case f: \ - for (i=x-1; i >= 1; --i, cur[img_n]=255,raw+=img_n,cur+=out_n,prior+=out_n) \ - for (k=0; k < img_n; ++k) - switch (filter) { - CASE(F_none) cur[k] = raw[k]; break; - CASE(F_sub) cur[k] = raw[k] + cur[k-out_n]; break; - CASE(F_up) cur[k] = raw[k] + prior[k]; break; - CASE(F_avg) cur[k] = raw[k] + ((prior[k] + cur[k-out_n])>>1); break; - CASE(F_paeth) cur[k] = (uint8) (raw[k] + paeth(cur[k-out_n],prior[k],prior[k-out_n])); break; - CASE(F_avg_first) cur[k] = raw[k] + (cur[k-out_n] >> 1); break; - CASE(F_paeth_first) cur[k] = (uint8) (raw[k] + paeth(cur[k-out_n],0,0)); break; - } - #undef CASE - } - } - return 1; -} - -static int create_png_image(png *a, uint8 *raw, uint32 raw_len, int out_n, int interlaced) -{ - uint8 *final; - int p; - int save; - if (!interlaced) - return create_png_image_raw(a, raw, raw_len, out_n, a->s->img_x, a->s->img_y); - save = stbi_png_partial; - stbi_png_partial = 0; - - // de-interlacing - final = (uint8 *) malloc(a->s->img_x * a->s->img_y * out_n); - for (p=0; p < 7; ++p) { - int xorig[] = { 0,4,0,2,0,1,0 }; - int yorig[] = { 0,0,4,0,2,0,1 }; - int xspc[] = { 8,8,4,4,2,2,1 }; - int yspc[] = { 8,8,8,4,4,2,2 }; - int i,j,x,y; - // pass1_x[4] = 0, pass1_x[5] = 1, pass1_x[12] = 1 - x = (a->s->img_x - xorig[p] + xspc[p]-1) / xspc[p]; - y = (a->s->img_y - yorig[p] + yspc[p]-1) / yspc[p]; - if (x && y) { - if (!create_png_image_raw(a, raw, raw_len, out_n, x, y)) { - free(final); - return 0; - } - for (j=0; j < y; ++j) - for (i=0; i < x; ++i) - memcpy(final + (j*yspc[p]+yorig[p])*a->s->img_x*out_n + (i*xspc[p]+xorig[p])*out_n, - a->out + (j*x+i)*out_n, out_n); - free(a->out); - raw += (x*out_n+1)*y; - raw_len -= (x*out_n+1)*y; - } - } - a->out = final; - - stbi_png_partial = save; - return 1; -} - -static int compute_transparency(png *z, uint8 tc[3], int out_n) -{ - stbi *s = z->s; - uint32 i, pixel_count = s->img_x * s->img_y; - uint8 *p = z->out; - - // compute color-based transparency, assuming we've - // already got 255 as the alpha value in the output - assert(out_n == 2 || out_n == 4); - - if (out_n == 2) { - for (i=0; i < pixel_count; ++i) { - p[1] = (p[0] == tc[0] ? 0 : 255); - p += 2; - } - } else { - for (i=0; i < pixel_count; ++i) { - if (p[0] == tc[0] && p[1] == tc[1] && p[2] == tc[2]) - p[3] = 0; - p += 4; - } - } - return 1; -} - -static int expand_palette(png *a, uint8 *palette, int len, int pal_img_n) -{ - uint32 i, pixel_count = a->s->img_x * a->s->img_y; - uint8 *p, *temp_out, *orig = a->out; - - p = (uint8 *) malloc(pixel_count * pal_img_n); - if (p == NULL) return e("outofmem", "Out of memory"); - - // between here and free(out) below, exitting would leak - temp_out = p; - - if (pal_img_n == 3) { - for (i=0; i < pixel_count; ++i) { - int n = orig[i]*4; - p[0] = palette[n ]; - p[1] = palette[n+1]; - p[2] = palette[n+2]; - p += 3; - } - } else { - for (i=0; i < pixel_count; ++i) { - int n = orig[i]*4; - p[0] = palette[n ]; - p[1] = palette[n+1]; - p[2] = palette[n+2]; - p[3] = palette[n+3]; - p += 4; - } - } - free(a->out); - a->out = temp_out; - - STBI_NOTUSED(len); - - return 1; -} - -static int stbi_unpremultiply_on_load = 0; -static int stbi_de_iphone_flag = 0; - -void stbi_set_unpremultiply_on_load(int flag_true_if_should_unpremultiply) -{ - stbi_unpremultiply_on_load = flag_true_if_should_unpremultiply; -} -void stbi_convert_iphone_png_to_rgb(int flag_true_if_should_convert) -{ - stbi_de_iphone_flag = flag_true_if_should_convert; -} - -static void stbi_de_iphone(png *z) -{ - stbi *s = z->s; - uint32 i, pixel_count = s->img_x * s->img_y; - uint8 *p = z->out; - - if (s->img_out_n == 3) { // convert bgr to rgb - for (i=0; i < pixel_count; ++i) { - uint8 t = p[0]; - p[0] = p[2]; - p[2] = t; - p += 3; - } - } else { - assert(s->img_out_n == 4); - if (stbi_unpremultiply_on_load) { - // convert bgr to rgb and unpremultiply - for (i=0; i < pixel_count; ++i) { - uint8 a = p[3]; - uint8 t = p[0]; - if (a) { - p[0] = p[2] * 255 / a; - p[1] = p[1] * 255 / a; - p[2] = t * 255 / a; - } else { - p[0] = p[2]; - p[2] = t; - } - p += 4; - } - } else { - // convert bgr to rgb - for (i=0; i < pixel_count; ++i) { - uint8 t = p[0]; - p[0] = p[2]; - p[2] = t; - p += 4; - } - } - } -} - -static int parse_png_file(png *z, int scan, int req_comp) -{ - uint8 palette[1024], pal_img_n=0; - uint8 has_trans=0, tc[3]; - uint32 ioff=0, idata_limit=0, i, pal_len=0; - int first=1,k,interlace=0, iphone=0; - stbi *s = z->s; - - z->expanded = NULL; - z->idata = NULL; - z->out = NULL; - - if (!check_png_header(s)) return 0; - - if (scan == SCAN_type) return 1; - - for (;;) { - chunk c = get_chunk_header(s); - switch (c.type) { - case PNG_TYPE('C','g','B','I'): - iphone = stbi_de_iphone_flag; - skip(s, c.length); - break; - case PNG_TYPE('I','H','D','R'): { - int depth,color,comp,filter; - if (!first) return e("multiple IHDR","Corrupt PNG"); - first = 0; - if (c.length != 13) return e("bad IHDR len","Corrupt PNG"); - s->img_x = get32(s); if (s->img_x > (1 << 24)) return e("too large","Very large image (corrupt?)"); - s->img_y = get32(s); if (s->img_y > (1 << 24)) return e("too large","Very large image (corrupt?)"); - depth = get8(s); if (depth != 8) return e("8bit only","PNG not supported: 8-bit only"); - color = get8(s); if (color > 6) return e("bad ctype","Corrupt PNG"); - if (color == 3) pal_img_n = 3; else if (color & 1) return e("bad ctype","Corrupt PNG"); - comp = get8(s); if (comp) return e("bad comp method","Corrupt PNG"); - filter= get8(s); if (filter) return e("bad filter method","Corrupt PNG"); - interlace = get8(s); if (interlace>1) return e("bad interlace method","Corrupt PNG"); - if (!s->img_x || !s->img_y) return e("0-pixel image","Corrupt PNG"); - if (!pal_img_n) { - s->img_n = (color & 2 ? 3 : 1) + (color & 4 ? 1 : 0); - if ((1 << 30) / s->img_x / s->img_n < s->img_y) return e("too large", "Image too large to decode"); - if (scan == SCAN_header) return 1; - } else { - // if paletted, then pal_n is our final components, and - // img_n is # components to decompress/filter. - s->img_n = 1; - if ((1 << 30) / s->img_x / 4 < s->img_y) return e("too large","Corrupt PNG"); - // if SCAN_header, have to scan to see if we have a tRNS - } - break; - } - - case PNG_TYPE('P','L','T','E'): { - if (first) return e("first not IHDR", "Corrupt PNG"); - if (c.length > 256*3) return e("invalid PLTE","Corrupt PNG"); - pal_len = c.length / 3; - if (pal_len * 3 != c.length) return e("invalid PLTE","Corrupt PNG"); - for (i=0; i < pal_len; ++i) { - palette[i*4+0] = get8u(s); - palette[i*4+1] = get8u(s); - palette[i*4+2] = get8u(s); - palette[i*4+3] = 255; - } - break; - } - - case PNG_TYPE('t','R','N','S'): { - if (first) return e("first not IHDR", "Corrupt PNG"); - if (z->idata) return e("tRNS after IDAT","Corrupt PNG"); - if (pal_img_n) { - if (scan == SCAN_header) { s->img_n = 4; return 1; } - if (pal_len == 0) return e("tRNS before PLTE","Corrupt PNG"); - if (c.length > pal_len) return e("bad tRNS len","Corrupt PNG"); - pal_img_n = 4; - for (i=0; i < c.length; ++i) - palette[i*4+3] = get8u(s); - } else { - if (!(s->img_n & 1)) return e("tRNS with alpha","Corrupt PNG"); - if (c.length != (uint32) s->img_n*2) return e("bad tRNS len","Corrupt PNG"); - has_trans = 1; - for (k=0; k < s->img_n; ++k) - tc[k] = (uint8) get16(s); // non 8-bit images will be larger - } - break; - } - - case PNG_TYPE('I','D','A','T'): { - if (first) return e("first not IHDR", "Corrupt PNG"); - if (pal_img_n && !pal_len) return e("no PLTE","Corrupt PNG"); - if (scan == SCAN_header) { s->img_n = pal_img_n; return 1; } - if (ioff + c.length > idata_limit) { - uint8 *p; - if (idata_limit == 0) idata_limit = c.length > 4096 ? c.length : 4096; - while (ioff + c.length > idata_limit) - idata_limit *= 2; - p = (uint8 *) realloc(z->idata, idata_limit); if (p == NULL) return e("outofmem", "Out of memory"); - z->idata = p; - } - if (!getn(s, z->idata+ioff,c.length)) return e("outofdata","Corrupt PNG"); - ioff += c.length; - break; - } - - case PNG_TYPE('I','E','N','D'): { - uint32 raw_len; - if (first) return e("first not IHDR", "Corrupt PNG"); - if (scan != SCAN_load) return 1; - if (z->idata == NULL) return e("no IDAT","Corrupt PNG"); - z->expanded = (uint8 *) stbi_zlib_decode_malloc_guesssize_headerflag((char *) z->idata, ioff, 16384, (int *) &raw_len, !iphone); - if (z->expanded == NULL) return 0; // zlib should set error - free(z->idata); z->idata = NULL; - if ((req_comp == s->img_n+1 && req_comp != 3 && !pal_img_n) || has_trans) - s->img_out_n = s->img_n+1; - else - s->img_out_n = s->img_n; - if (!create_png_image(z, z->expanded, raw_len, s->img_out_n, interlace)) return 0; - if (has_trans) - if (!compute_transparency(z, tc, s->img_out_n)) return 0; - if (iphone && s->img_out_n > 2) - stbi_de_iphone(z); - if (pal_img_n) { - // pal_img_n == 3 or 4 - s->img_n = pal_img_n; // record the actual colors we had - s->img_out_n = pal_img_n; - if (req_comp >= 3) s->img_out_n = req_comp; - if (!expand_palette(z, palette, pal_len, s->img_out_n)) - return 0; - } - free(z->expanded); z->expanded = NULL; - return 1; - } - - default: - // if critical, fail - if (first) return e("first not IHDR", "Corrupt PNG"); - if ((c.type & (1 << 29)) == 0) { - #ifndef STBI_NO_FAILURE_STRINGS - // not threadsafe - static char invalid_chunk[] = "XXXX chunk not known"; - invalid_chunk[0] = (uint8) (c.type >> 24); - invalid_chunk[1] = (uint8) (c.type >> 16); - invalid_chunk[2] = (uint8) (c.type >> 8); - invalid_chunk[3] = (uint8) (c.type >> 0); - #endif - return e(invalid_chunk, "PNG not supported: unknown chunk type"); - } - skip(s, c.length); - break; - } - // end of chunk, read and skip CRC - get32(s); - } -} - -static unsigned char *do_png(png *p, int *x, int *y, int *n, int req_comp) -{ - unsigned char *result=NULL; - if (req_comp < 0 || req_comp > 4) return epuc("bad req_comp", "Internal error"); - if (parse_png_file(p, SCAN_load, req_comp)) { - result = p->out; - p->out = NULL; - if (req_comp && req_comp != p->s->img_out_n) { - result = convert_format(result, p->s->img_out_n, req_comp, p->s->img_x, p->s->img_y); - p->s->img_out_n = req_comp; - if (result == NULL) return result; - } - *x = p->s->img_x; - *y = p->s->img_y; - if (n) *n = p->s->img_n; - } - free(p->out); p->out = NULL; - free(p->expanded); p->expanded = NULL; - free(p->idata); p->idata = NULL; - - return result; -} - -static unsigned char *stbi_png_load(stbi *s, int *x, int *y, int *comp, int req_comp) -{ - png p; - p.s = s; - return do_png(&p, x,y,comp,req_comp); -} - -static int stbi_png_test(stbi *s) -{ - int r; - r = check_png_header(s); - stbi_rewind(s); - return r; -} - -static int stbi_png_info_raw(png *p, int *x, int *y, int *comp) -{ - if (!parse_png_file(p, SCAN_header, 0)) { - stbi_rewind( p->s ); - return 0; - } - if (x) *x = p->s->img_x; - if (y) *y = p->s->img_y; - if (comp) *comp = p->s->img_n; - return 1; -} - -static int stbi_png_info(stbi *s, int *x, int *y, int *comp) -{ - png p; - p.s = s; - return stbi_png_info_raw(&p, x, y, comp); -} - -// Microsoft/Windows BMP image - -static int bmp_test(stbi *s) -{ - int sz; - if (get8(s) != 'B') return 0; - if (get8(s) != 'M') return 0; - get32le(s); // discard filesize - get16le(s); // discard reserved - get16le(s); // discard reserved - get32le(s); // discard data offset - sz = get32le(s); - if (sz == 12 || sz == 40 || sz == 56 || sz == 108) return 1; - return 0; -} - -static int stbi_bmp_test(stbi *s) -{ - int r = bmp_test(s); - stbi_rewind(s); - return r; -} - - -// returns 0..31 for the highest set bit -static int high_bit(unsigned int z) -{ - int n=0; - if (z == 0) return -1; - if (z >= 0x10000) n += 16, z >>= 16; - if (z >= 0x00100) n += 8, z >>= 8; - if (z >= 0x00010) n += 4, z >>= 4; - if (z >= 0x00004) n += 2, z >>= 2; - if (z >= 0x00002) n += 1, z >>= 1; - return n; -} - -static int bitcount(unsigned int a) -{ - a = (a & 0x55555555) + ((a >> 1) & 0x55555555); // max 2 - a = (a & 0x33333333) + ((a >> 2) & 0x33333333); // max 4 - a = (a + (a >> 4)) & 0x0f0f0f0f; // max 8 per 4, now 8 bits - a = (a + (a >> 8)); // max 16 per 8 bits - a = (a + (a >> 16)); // max 32 per 8 bits - return a & 0xff; -} - -static int shiftsigned(int v, int shift, int bits) -{ - int result; - int z=0; - - if (shift < 0) v <<= -shift; - else v >>= shift; - result = v; - - z = bits; - while (z < 8) { - result += v >> z; - z += bits; - } - return result; -} - -static stbi_uc *bmp_load(stbi *s, int *x, int *y, int *comp, int req_comp) -{ - uint8 *out; - unsigned int mr=0,mg=0,mb=0,ma=0, fake_a=0; - stbi_uc pal[256][4]; - int psize=0,i,j,compress=0,width; - int bpp, flip_vertically, pad, target, offset, hsz; - if (get8(s) != 'B' || get8(s) != 'M') return epuc("not BMP", "Corrupt BMP"); - get32le(s); // discard filesize - get16le(s); // discard reserved - get16le(s); // discard reserved - offset = get32le(s); - hsz = get32le(s); - if (hsz != 12 && hsz != 40 && hsz != 56 && hsz != 108) return epuc("unknown BMP", "BMP type not supported: unknown"); - if (hsz == 12) { - s->img_x = get16le(s); - s->img_y = get16le(s); - } else { - s->img_x = get32le(s); - s->img_y = get32le(s); - } - if (get16le(s) != 1) return epuc("bad BMP", "bad BMP"); - bpp = get16le(s); - if (bpp == 1) return epuc("monochrome", "BMP type not supported: 1-bit"); - flip_vertically = ((int) s->img_y) > 0; - s->img_y = abs((int) s->img_y); - if (hsz == 12) { - if (bpp < 24) - psize = (offset - 14 - 24) / 3; - } else { - compress = get32le(s); - if (compress == 1 || compress == 2) return epuc("BMP RLE", "BMP type not supported: RLE"); - get32le(s); // discard sizeof - get32le(s); // discard hres - get32le(s); // discard vres - get32le(s); // discard colorsused - get32le(s); // discard max important - if (hsz == 40 || hsz == 56) { - if (hsz == 56) { - get32le(s); - get32le(s); - get32le(s); - get32le(s); - } - if (bpp == 16 || bpp == 32) { - mr = mg = mb = 0; - if (compress == 0) { - if (bpp == 32) { - mr = 0xffu << 16; - mg = 0xffu << 8; - mb = 0xffu << 0; - ma = 0xffu << 24; - fake_a = 1; // @TODO: check for cases like alpha value is all 0 and switch it to 255 - } else { - mr = 31u << 10; - mg = 31u << 5; - mb = 31u << 0; - } - } else if (compress == 3) { - mr = get32le(s); - mg = get32le(s); - mb = get32le(s); - // not documented, but generated by photoshop and handled by mspaint - if (mr == mg && mg == mb) { - // ?!?!? - return epuc("bad BMP", "bad BMP"); - } - } else - return epuc("bad BMP", "bad BMP"); - } - } else { - assert(hsz == 108); - mr = get32le(s); - mg = get32le(s); - mb = get32le(s); - ma = get32le(s); - get32le(s); // discard color space - for (i=0; i < 12; ++i) - get32le(s); // discard color space parameters - } - if (bpp < 16) - psize = (offset - 14 - hsz) >> 2; - } - s->img_n = ma ? 4 : 3; - if (req_comp && req_comp >= 3) // we can directly decode 3 or 4 - target = req_comp; - else - target = s->img_n; // if they want monochrome, we'll post-convert - out = (stbi_uc *) malloc(target * s->img_x * s->img_y); - if (!out) return epuc("outofmem", "Out of memory"); - if (bpp < 16) { - int z=0; - if (psize == 0 || psize > 256) { free(out); return epuc("invalid", "Corrupt BMP"); } - for (i=0; i < psize; ++i) { - pal[i][2] = get8u(s); - pal[i][1] = get8u(s); - pal[i][0] = get8u(s); - if (hsz != 12) get8(s); - pal[i][3] = 255; - } - skip(s, offset - 14 - hsz - psize * (hsz == 12 ? 3 : 4)); - if (bpp == 4) width = (s->img_x + 1) >> 1; - else if (bpp == 8) width = s->img_x; - else { free(out); return epuc("bad bpp", "Corrupt BMP"); } - pad = (-width)&3; - for (j=0; j < (int) s->img_y; ++j) { - for (i=0; i < (int) s->img_x; i += 2) { - int v=get8(s),v2=0; - if (bpp == 4) { - v2 = v & 15; - v >>= 4; - } - out[z++] = pal[v][0]; - out[z++] = pal[v][1]; - out[z++] = pal[v][2]; - if (target == 4) out[z++] = 255; - if (i+1 == (int) s->img_x) break; - v = (bpp == 8) ? get8(s) : v2; - out[z++] = pal[v][0]; - out[z++] = pal[v][1]; - out[z++] = pal[v][2]; - if (target == 4) out[z++] = 255; - } - skip(s, pad); - } - } else { - int rshift=0,gshift=0,bshift=0,ashift=0,rcount=0,gcount=0,bcount=0,acount=0; - int z = 0; - int easy=0; - skip(s, offset - 14 - hsz); - if (bpp == 24) width = 3 * s->img_x; - else if (bpp == 16) width = 2*s->img_x; - else /* bpp = 32 and pad = 0 */ width=0; - pad = (-width) & 3; - if (bpp == 24) { - easy = 1; - } else if (bpp == 32) { - if (mb == 0xff && mg == 0xff00 && mr == 0x00ff0000 && ma == 0xff000000) - easy = 2; - } - if (!easy) { - if (!mr || !mg || !mb) { free(out); return epuc("bad masks", "Corrupt BMP"); } - // right shift amt to put high bit in position #7 - rshift = high_bit(mr)-7; rcount = bitcount(mr); - gshift = high_bit(mg)-7; gcount = bitcount(mr); - bshift = high_bit(mb)-7; bcount = bitcount(mr); - ashift = high_bit(ma)-7; acount = bitcount(mr); - } - for (j=0; j < (int) s->img_y; ++j) { - if (easy) { - for (i=0; i < (int) s->img_x; ++i) { - int a; - out[z+2] = get8u(s); - out[z+1] = get8u(s); - out[z+0] = get8u(s); - z += 3; - a = (easy == 2 ? get8(s) : 255); - if (target == 4) out[z++] = (uint8) a; - } - } else { - for (i=0; i < (int) s->img_x; ++i) { - uint32 v = (bpp == 16 ? get16le(s) : get32le(s)); - int a; - out[z++] = (uint8) shiftsigned(v & mr, rshift, rcount); - out[z++] = (uint8) shiftsigned(v & mg, gshift, gcount); - out[z++] = (uint8) shiftsigned(v & mb, bshift, bcount); - a = (ma ? shiftsigned(v & ma, ashift, acount) : 255); - if (target == 4) out[z++] = (uint8) a; - } - } - skip(s, pad); - } - } - if (flip_vertically) { - stbi_uc t; - for (j=0; j < (int) s->img_y>>1; ++j) { - stbi_uc *p1 = out + j *s->img_x*target; - stbi_uc *p2 = out + (s->img_y-1-j)*s->img_x*target; - for (i=0; i < (int) s->img_x*target; ++i) { - t = p1[i], p1[i] = p2[i], p2[i] = t; - } - } - } - - if (req_comp && req_comp != target) { - out = convert_format(out, target, req_comp, s->img_x, s->img_y); - if (out == NULL) return out; // convert_format frees input on failure - } - - *x = s->img_x; - *y = s->img_y; - if (comp) *comp = s->img_n; - return out; -} - -static stbi_uc *stbi_bmp_load(stbi *s,int *x, int *y, int *comp, int req_comp) -{ - return bmp_load(s, x,y,comp,req_comp); -} - - -// Targa Truevision - TGA -// by Jonathan Dummer - -static int tga_info(stbi *s, int *x, int *y, int *comp) -{ - int tga_w, tga_h, tga_comp; - int sz; - get8u(s); // discard Offset - sz = get8u(s); // color type - if( sz > 1 ) { - stbi_rewind(s); - return 0; // only RGB or indexed allowed - } - sz = get8u(s); // image type - // only RGB or grey allowed, +/- RLE - if ((sz != 1) && (sz != 2) && (sz != 3) && (sz != 9) && (sz != 10) && (sz != 11)) return 0; - skip(s,9); - tga_w = get16le(s); - if( tga_w < 1 ) { - stbi_rewind(s); - return 0; // test width - } - tga_h = get16le(s); - if( tga_h < 1 ) { - stbi_rewind(s); - return 0; // test height - } - sz = get8(s); // bits per pixel - // only RGB or RGBA or grey allowed - if ((sz != 8) && (sz != 16) && (sz != 24) && (sz != 32)) { - stbi_rewind(s); - return 0; - } - tga_comp = sz; - if (x) *x = tga_w; - if (y) *y = tga_h; - if (comp) *comp = tga_comp / 8; - return 1; // seems to have passed everything -} - -int stbi_tga_info(stbi *s, int *x, int *y, int *comp) -{ - return tga_info(s, x, y, comp); -} - -static int tga_test(stbi *s) -{ - int sz; - get8u(s); // discard Offset - sz = get8u(s); // color type - if ( sz > 1 ) return 0; // only RGB or indexed allowed - sz = get8u(s); // image type - if ( (sz != 1) && (sz != 2) && (sz != 3) && (sz != 9) && (sz != 10) && (sz != 11) ) return 0; // only RGB or grey allowed, +/- RLE - get16(s); // discard palette start - get16(s); // discard palette length - get8(s); // discard bits per palette color entry - get16(s); // discard x origin - get16(s); // discard y origin - if ( get16(s) < 1 ) return 0; // test width - if ( get16(s) < 1 ) return 0; // test height - sz = get8(s); // bits per pixel - if ( (sz != 8) && (sz != 16) && (sz != 24) && (sz != 32) ) return 0; // only RGB or RGBA or grey allowed - return 1; // seems to have passed everything -} - -static int stbi_tga_test(stbi *s) -{ - int res = tga_test(s); - stbi_rewind(s); - return res; -} - -static stbi_uc *tga_load(stbi *s, int *x, int *y, int *comp, int req_comp) -{ - // read in the TGA header stuff - int tga_offset = get8u(s); - int tga_indexed = get8u(s); - int tga_image_type = get8u(s); - int tga_is_RLE = 0; - int tga_palette_start = get16le(s); - int tga_palette_len = get16le(s); - int tga_palette_bits = get8u(s); - int tga_x_origin = get16le(s); - int tga_y_origin = get16le(s); - int tga_width = get16le(s); - int tga_height = get16le(s); - int tga_bits_per_pixel = get8u(s); - int tga_inverted = get8u(s); - // image data - unsigned char *tga_data; - unsigned char *tga_palette = NULL; - int i, j; - unsigned char raw_data[4]; - unsigned char trans_data[4]; - int RLE_count = 0; - int RLE_repeating = 0; - int read_next_pixel = 1; - - // do a tiny bit of precessing - if ( tga_image_type >= 8 ) - { - tga_image_type -= 8; - tga_is_RLE = 1; - } - /* int tga_alpha_bits = tga_inverted & 15; */ - tga_inverted = 1 - ((tga_inverted >> 5) & 1); - - // error check - if ( //(tga_indexed) || - (tga_width < 1) || (tga_height < 1) || - (tga_image_type < 1) || (tga_image_type > 3) || - ((tga_bits_per_pixel != 8) && (tga_bits_per_pixel != 16) && - (tga_bits_per_pixel != 24) && (tga_bits_per_pixel != 32)) - ) - { - return NULL; // we don't report this as a bad TGA because we don't even know if it's TGA - } - - // If I'm paletted, then I'll use the number of bits from the palette - if ( tga_indexed ) - { - tga_bits_per_pixel = tga_palette_bits; - } - - // tga info - *x = tga_width; - *y = tga_height; - if ( (req_comp < 1) || (req_comp > 4) ) - { - // just use whatever the file was - req_comp = tga_bits_per_pixel / 8; - *comp = req_comp; - } else - { - // force a new number of components - *comp = tga_bits_per_pixel/8; - } - tga_data = (unsigned char*)malloc( tga_width * tga_height * req_comp ); - if (!tga_data) return epuc("outofmem", "Out of memory"); - - // skip to the data's starting position (offset usually = 0) - skip(s, tga_offset ); - // do I need to load a palette? - if ( tga_indexed ) - { - // any data to skip? (offset usually = 0) - skip(s, tga_palette_start ); - // load the palette - tga_palette = (unsigned char*)malloc( tga_palette_len * tga_palette_bits / 8 ); - if (!tga_palette) return epuc("outofmem", "Out of memory"); - if (!getn(s, tga_palette, tga_palette_len * tga_palette_bits / 8 )) { - free(tga_data); - free(tga_palette); - return epuc("bad palette", "Corrupt TGA"); - } - } - // load the data - trans_data[0] = trans_data[1] = trans_data[2] = trans_data[3] = 0; - for (i=0; i < tga_width * tga_height; ++i) - { - // if I'm in RLE mode, do I need to get a RLE chunk? - if ( tga_is_RLE ) - { - if ( RLE_count == 0 ) - { - // yep, get the next byte as a RLE command - int RLE_cmd = get8u(s); - RLE_count = 1 + (RLE_cmd & 127); - RLE_repeating = RLE_cmd >> 7; - read_next_pixel = 1; - } else if ( !RLE_repeating ) - { - read_next_pixel = 1; - } - } else - { - read_next_pixel = 1; - } - // OK, if I need to read a pixel, do it now - if ( read_next_pixel ) - { - // load however much data we did have - if ( tga_indexed ) - { - // read in 1 byte, then perform the lookup - int pal_idx = get8u(s); - if ( pal_idx >= tga_palette_len ) - { - // invalid index - pal_idx = 0; - } - pal_idx *= tga_bits_per_pixel / 8; - for (j = 0; j*8 < tga_bits_per_pixel; ++j) - { - raw_data[j] = tga_palette[pal_idx+j]; - } - } else - { - // read in the data raw - for (j = 0; j*8 < tga_bits_per_pixel; ++j) - { - raw_data[j] = get8u(s); - } - } - // convert raw to the intermediate format - switch (tga_bits_per_pixel) - { - case 8: - // Luminous => RGBA - trans_data[0] = raw_data[0]; - trans_data[1] = raw_data[0]; - trans_data[2] = raw_data[0]; - trans_data[3] = 255; - break; - case 16: - // Luminous,Alpha => RGBA - trans_data[0] = raw_data[0]; - trans_data[1] = raw_data[0]; - trans_data[2] = raw_data[0]; - trans_data[3] = raw_data[1]; - break; - case 24: - // BGR => RGBA - trans_data[0] = raw_data[2]; - trans_data[1] = raw_data[1]; - trans_data[2] = raw_data[0]; - trans_data[3] = 255; - break; - case 32: - // BGRA => RGBA - trans_data[0] = raw_data[2]; - trans_data[1] = raw_data[1]; - trans_data[2] = raw_data[0]; - trans_data[3] = raw_data[3]; - break; - } - // clear the reading flag for the next pixel - read_next_pixel = 0; - } // end of reading a pixel - // convert to final format - switch (req_comp) - { - case 1: - // RGBA => Luminance - tga_data[i*req_comp+0] = compute_y(trans_data[0],trans_data[1],trans_data[2]); - break; - case 2: - // RGBA => Luminance,Alpha - tga_data[i*req_comp+0] = compute_y(trans_data[0],trans_data[1],trans_data[2]); - tga_data[i*req_comp+1] = trans_data[3]; - break; - case 3: - // RGBA => RGB - tga_data[i*req_comp+0] = trans_data[0]; - tga_data[i*req_comp+1] = trans_data[1]; - tga_data[i*req_comp+2] = trans_data[2]; - break; - case 4: - // RGBA => RGBA - tga_data[i*req_comp+0] = trans_data[0]; - tga_data[i*req_comp+1] = trans_data[1]; - tga_data[i*req_comp+2] = trans_data[2]; - tga_data[i*req_comp+3] = trans_data[3]; - break; - } - // in case we're in RLE mode, keep counting down - --RLE_count; - } - // do I need to invert the image? - if ( tga_inverted ) - { - for (j = 0; j*2 < tga_height; ++j) - { - int index1 = j * tga_width * req_comp; - int index2 = (tga_height - 1 - j) * tga_width * req_comp; - for (i = tga_width * req_comp; i > 0; --i) - { - unsigned char temp = tga_data[index1]; - tga_data[index1] = tga_data[index2]; - tga_data[index2] = temp; - ++index1; - ++index2; - } - } - } - // clear my palette, if I had one - if ( tga_palette != NULL ) - { - free( tga_palette ); - } - // the things I do to get rid of an error message, and yet keep - // Microsoft's C compilers happy... [8^( - tga_palette_start = tga_palette_len = tga_palette_bits = - tga_x_origin = tga_y_origin = 0; - // OK, done - return tga_data; -} - -static stbi_uc *stbi_tga_load(stbi *s, int *x, int *y, int *comp, int req_comp) -{ - return tga_load(s,x,y,comp,req_comp); -} - - -// ************************************************************************************************* -// Photoshop PSD loader -- PD by Thatcher Ulrich, integration by Nicolas Schulz, tweaked by STB - -static int psd_test(stbi *s) -{ - if (get32(s) != 0x38425053) return 0; // "8BPS" - else return 1; -} - -static int stbi_psd_test(stbi *s) -{ - int r = psd_test(s); - stbi_rewind(s); - return r; -} - -static stbi_uc *psd_load(stbi *s, int *x, int *y, int *comp, int req_comp) -{ - int pixelCount; - int channelCount, compression; - int channel, i, count, len; - int w,h; - uint8 *out; - - // Check identifier - if (get32(s) != 0x38425053) // "8BPS" - return epuc("not PSD", "Corrupt PSD image"); - - // Check file type version. - if (get16(s) != 1) - return epuc("wrong version", "Unsupported version of PSD image"); - - // Skip 6 reserved bytes. - skip(s, 6 ); - - // Read the number of channels (R, G, B, A, etc). - channelCount = get16(s); - if (channelCount < 0 || channelCount > 16) - return epuc("wrong channel count", "Unsupported number of channels in PSD image"); - - // Read the rows and columns of the image. - h = get32(s); - w = get32(s); - - // Make sure the depth is 8 bits. - if (get16(s) != 8) - return epuc("unsupported bit depth", "PSD bit depth is not 8 bit"); - - // Make sure the color mode is RGB. - // Valid options are: - // 0: Bitmap - // 1: Grayscale - // 2: Indexed color - // 3: RGB color - // 4: CMYK color - // 7: Multichannel - // 8: Duotone - // 9: Lab color - if (get16(s) != 3) - return epuc("wrong color format", "PSD is not in RGB color format"); - - // Skip the Mode Data. (It's the palette for indexed color; other info for other modes.) - skip(s,get32(s) ); - - // Skip the image resources. (resolution, pen tool paths, etc) - skip(s, get32(s) ); - - // Skip the reserved data. - skip(s, get32(s) ); - - // Find out if the data is compressed. - // Known values: - // 0: no compression - // 1: RLE compressed - compression = get16(s); - if (compression > 1) - return epuc("bad compression", "PSD has an unknown compression format"); - - // Create the destination image. - out = (stbi_uc *) malloc(4 * w*h); - if (!out) return epuc("outofmem", "Out of memory"); - pixelCount = w*h; - - // Initialize the data to zero. - //memset( out, 0, pixelCount * 4 ); - - // Finally, the image data. - if (compression) { - // RLE as used by .PSD and .TIFF - // Loop until you get the number of unpacked bytes you are expecting: - // Read the next source byte into n. - // If n is between 0 and 127 inclusive, copy the next n+1 bytes literally. - // Else if n is between -127 and -1 inclusive, copy the next byte -n+1 times. - // Else if n is 128, noop. - // Endloop - - // The RLE-compressed data is preceeded by a 2-byte data count for each row in the data, - // which we're going to just skip. - skip(s, h * channelCount * 2 ); - - // Read the RLE data by channel. - for (channel = 0; channel < 4; channel++) { - uint8 *p; - - p = out+channel; - if (channel >= channelCount) { - // Fill this channel with default data. - for (i = 0; i < pixelCount; i++) *p = (channel == 3 ? 255 : 0), p += 4; - } else { - // Read the RLE data. - count = 0; - while (count < pixelCount) { - len = get8(s); - if (len == 128) { - // No-op. - } else if (len < 128) { - // Copy next len+1 bytes literally. - len++; - count += len; - while (len) { - *p = get8u(s); - p += 4; - len--; - } - } else if (len > 128) { - uint8 val; - // Next -len+1 bytes in the dest are replicated from next source byte. - // (Interpret len as a negative 8-bit int.) - len ^= 0x0FF; - len += 2; - val = get8u(s); - count += len; - while (len) { - *p = val; - p += 4; - len--; - } - } - } - } - } - - } else { - // We're at the raw image data. It's each channel in order (Red, Green, Blue, Alpha, ...) - // where each channel consists of an 8-bit value for each pixel in the image. - - // Read the data by channel. - for (channel = 0; channel < 4; channel++) { - uint8 *p; - - p = out + channel; - if (channel > channelCount) { - // Fill this channel with default data. - for (i = 0; i < pixelCount; i++) *p = channel == 3 ? 255 : 0, p += 4; - } else { - // Read the data. - for (i = 0; i < pixelCount; i++) - *p = get8u(s), p += 4; - } - } - } - - if (req_comp && req_comp != 4) { - out = convert_format(out, 4, req_comp, w, h); - if (out == NULL) return out; // convert_format frees input on failure - } - - if (comp) *comp = channelCount; - *y = h; - *x = w; - - return out; -} - -static stbi_uc *stbi_psd_load(stbi *s, int *x, int *y, int *comp, int req_comp) -{ - return psd_load(s,x,y,comp,req_comp); -} - -// ************************************************************************************************* -// Softimage PIC loader -// by Tom Seddon -// -// See http://softimage.wiki.softimage.com/index.php/INFO:_PIC_file_format -// See http://ozviz.wasp.uwa.edu.au/~pbourke/dataformats/softimagepic/ - -static int pic_is4(stbi *s,const char *str) -{ - int i; - for (i=0; i<4; ++i) - if (get8(s) != (stbi_uc)str[i]) - return 0; - - return 1; -} - -static int pic_test(stbi *s) -{ - int i; - - if (!pic_is4(s,"\x53\x80\xF6\x34")) - return 0; - - for(i=0;i<84;++i) - get8(s); - - if (!pic_is4(s,"PICT")) - return 0; - - return 1; -} - -typedef struct -{ - stbi_uc size,type,channel; -} pic_packet_t; - -static stbi_uc *pic_readval(stbi *s, int channel, stbi_uc *dest) -{ - int mask=0x80, i; - - for (i=0; i<4; ++i, mask>>=1) { - if (channel & mask) { - if (at_eof(s)) return epuc("bad file","PIC file too short"); - dest[i]=get8u(s); - } - } - - return dest; -} - -static void pic_copyval(int channel,stbi_uc *dest,const stbi_uc *src) -{ - int mask=0x80,i; - - for (i=0;i<4; ++i, mask>>=1) - if (channel&mask) - dest[i]=src[i]; -} - -static stbi_uc *pic_load2(stbi *s,int width,int height,int *comp, stbi_uc *result) -{ - int act_comp=0,num_packets=0,y,chained; - pic_packet_t packets[10]; - - // this will (should...) cater for even some bizarre stuff like having data - // for the same channel in multiple packets. - do { - pic_packet_t *packet; - - if (num_packets==sizeof(packets)/sizeof(packets[0])) - return epuc("bad format","too many packets"); - - packet = &packets[num_packets++]; - - chained = get8(s); - packet->size = get8u(s); - packet->type = get8u(s); - packet->channel = get8u(s); - - act_comp |= packet->channel; - - if (at_eof(s)) return epuc("bad file","file too short (reading packets)"); - if (packet->size != 8) return epuc("bad format","packet isn't 8bpp"); - } while (chained); - - *comp = (act_comp & 0x10 ? 4 : 3); // has alpha channel? - - for(y=0; ytype) { - default: - return epuc("bad format","packet has bad compression type"); - - case 0: {//uncompressed - int x; - - for(x=0;xchannel,dest)) - return 0; - break; - } - - case 1://Pure RLE - { - int left=width, i; - - while (left>0) { - stbi_uc count,value[4]; - - count=get8u(s); - if (at_eof(s)) return epuc("bad file","file too short (pure read count)"); - - if (count > left) - count = (uint8) left; - - if (!pic_readval(s,packet->channel,value)) return 0; - - for(i=0; ichannel,dest,value); - left -= count; - } - } - break; - - case 2: {//Mixed RLE - int left=width; - while (left>0) { - int count = get8(s), i; - if (at_eof(s)) return epuc("bad file","file too short (mixed read count)"); - - if (count >= 128) { // Repeated - stbi_uc value[4]; - int i; - - if (count==128) - count = get16(s); - else - count -= 127; - if (count > left) - return epuc("bad file","scanline overrun"); - - if (!pic_readval(s,packet->channel,value)) - return 0; - - for(i=0;ichannel,dest,value); - } else { // Raw - ++count; - if (count>left) return epuc("bad file","scanline overrun"); - - for(i=0;ichannel,dest)) - return 0; - } - left-=count; - } - break; - } - } - } - } - - return result; -} - -static stbi_uc *pic_load(stbi *s,int *px,int *py,int *comp,int req_comp) -{ - stbi_uc *result; - int i, x,y; - - for (i=0; i<92; ++i) - get8(s); - - x = get16(s); - y = get16(s); - if (at_eof(s)) return epuc("bad file","file too short (pic header)"); - if ((1 << 28) / x < y) return epuc("too large", "Image too large to decode"); - - get32(s); //skip `ratio' - get16(s); //skip `fields' - get16(s); //skip `pad' - - // intermediate buffer is RGBA - result = (stbi_uc *) malloc(x*y*4); - memset(result, 0xff, x*y*4); - - if (!pic_load2(s,x,y,comp, result)) { - free(result); - result=0; - } - *px = x; - *py = y; - if (req_comp == 0) req_comp = *comp; - result=convert_format(result,4,req_comp,x,y); - - return result; -} - -static int stbi_pic_test(stbi *s) -{ - int r = pic_test(s); - stbi_rewind(s); - return r; -} - -static stbi_uc *stbi_pic_load(stbi *s, int *x, int *y, int *comp, int req_comp) -{ - return pic_load(s,x,y,comp,req_comp); -} - -// ************************************************************************************************* -// GIF loader -- public domain by Jean-Marc Lienher -- simplified/shrunk by stb -typedef struct stbi_gif_lzw_struct { - int16 prefix; - uint8 first; - uint8 suffix; -} stbi_gif_lzw; - -typedef struct stbi_gif_struct -{ - int w,h; - stbi_uc *out; // output buffer (always 4 components) - int flags, bgindex, ratio, transparent, eflags; - uint8 pal[256][4]; - uint8 lpal[256][4]; - stbi_gif_lzw codes[4096]; - uint8 *color_table; - int parse, step; - int lflags; - int start_x, start_y; - int max_x, max_y; - int cur_x, cur_y; - int line_size; -} stbi_gif; - -static int gif_test(stbi *s) -{ - int sz; - if (get8(s) != 'G' || get8(s) != 'I' || get8(s) != 'F' || get8(s) != '8') return 0; - sz = get8(s); - if (sz != '9' && sz != '7') return 0; - if (get8(s) != 'a') return 0; - return 1; -} - -static int stbi_gif_test(stbi *s) -{ - int r = gif_test(s); - stbi_rewind(s); - return r; -} - -static void stbi_gif_parse_colortable(stbi *s, uint8 pal[256][4], int num_entries, int transp) -{ - int i; - for (i=0; i < num_entries; ++i) { - pal[i][2] = get8u(s); - pal[i][1] = get8u(s); - pal[i][0] = get8u(s); - pal[i][3] = transp ? 0 : 255; - } -} - -static int stbi_gif_header(stbi *s, stbi_gif *g, int *comp, int is_info) -{ - uint8 version; - if (get8(s) != 'G' || get8(s) != 'I' || get8(s) != 'F' || get8(s) != '8') - return e("not GIF", "Corrupt GIF"); - - version = get8u(s); - if (version != '7' && version != '9') return e("not GIF", "Corrupt GIF"); - if (get8(s) != 'a') return e("not GIF", "Corrupt GIF"); - - failure_reason = ""; - g->w = get16le(s); - g->h = get16le(s); - g->flags = get8(s); - g->bgindex = get8(s); - g->ratio = get8(s); - g->transparent = -1; - - if (comp != 0) *comp = 4; // can't actually tell whether it's 3 or 4 until we parse the comments - - if (is_info) return 1; - - if (g->flags & 0x80) - stbi_gif_parse_colortable(s,g->pal, 2 << (g->flags & 7), -1); - - return 1; -} - -static int stbi_gif_info_raw(stbi *s, int *x, int *y, int *comp) -{ - stbi_gif g; - if (!stbi_gif_header(s, &g, comp, 1)) { - stbi_rewind( s ); - return 0; - } - if (x) *x = g.w; - if (y) *y = g.h; - return 1; -} - -static void stbi_out_gif_code(stbi_gif *g, uint16 code) -{ - uint8 *p, *c; - - // recurse to decode the prefixes, since the linked-list is backwards, - // and working backwards through an interleaved image would be nasty - if (g->codes[code].prefix >= 0) - stbi_out_gif_code(g, g->codes[code].prefix); - - if (g->cur_y >= g->max_y) return; - - p = &g->out[g->cur_x + g->cur_y]; - c = &g->color_table[g->codes[code].suffix * 4]; - - if (c[3] >= 128) { - p[0] = c[2]; - p[1] = c[1]; - p[2] = c[0]; - p[3] = c[3]; - } - g->cur_x += 4; - - if (g->cur_x >= g->max_x) { - g->cur_x = g->start_x; - g->cur_y += g->step; - - while (g->cur_y >= g->max_y && g->parse > 0) { - g->step = (1 << g->parse) * g->line_size; - g->cur_y = g->start_y + (g->step >> 1); - --g->parse; - } - } -} - -static uint8 *stbi_process_gif_raster(stbi *s, stbi_gif *g) -{ - uint8 lzw_cs; - int32 len, code; - uint32 first; - int32 codesize, codemask, avail, oldcode, bits, valid_bits, clear; - stbi_gif_lzw *p; - - lzw_cs = get8u(s); - clear = 1 << lzw_cs; - first = 1; - codesize = lzw_cs + 1; - codemask = (1 << codesize) - 1; - bits = 0; - valid_bits = 0; - for (code = 0; code < clear; code++) { - g->codes[code].prefix = -1; - g->codes[code].first = (uint8) code; - g->codes[code].suffix = (uint8) code; - } - - // support no starting clear code - avail = clear+2; - oldcode = -1; - - len = 0; - for(;;) { - if (valid_bits < codesize) { - if (len == 0) { - len = get8(s); // start new block - if (len == 0) - return g->out; - } - --len; - bits |= (int32) get8(s) << valid_bits; - valid_bits += 8; - } else { - int32 code = bits & codemask; - bits >>= codesize; - valid_bits -= codesize; - // @OPTIMIZE: is there some way we can accelerate the non-clear path? - if (code == clear) { // clear code - codesize = lzw_cs + 1; - codemask = (1 << codesize) - 1; - avail = clear + 2; - oldcode = -1; - first = 0; - } else if (code == clear + 1) { // end of stream code - skip(s, len); - while ((len = get8(s)) > 0) - skip(s,len); - return g->out; - } else if (code <= avail) { - if (first) return epuc("no clear code", "Corrupt GIF"); - - if (oldcode >= 0) { - p = &g->codes[avail++]; - if (avail > 4096) return epuc("too many codes", "Corrupt GIF"); - p->prefix = (int16) oldcode; - p->first = g->codes[oldcode].first; - p->suffix = (code == avail) ? p->first : g->codes[code].first; - } else if (code == avail) - return epuc("illegal code in raster", "Corrupt GIF"); - - stbi_out_gif_code(g, (uint16) code); - - if ((avail & codemask) == 0 && avail <= 0x0FFF) { - codesize++; - codemask = (1 << codesize) - 1; - } - - oldcode = code; - } else { - return epuc("illegal code in raster", "Corrupt GIF"); - } - } - } -} - -static void stbi_fill_gif_background(stbi_gif *g) -{ - int i; - uint8 *c = g->pal[g->bgindex]; - // @OPTIMIZE: write a dword at a time - for (i = 0; i < g->w * g->h * 4; i += 4) { - uint8 *p = &g->out[i]; - p[0] = c[2]; - p[1] = c[1]; - p[2] = c[0]; - p[3] = c[3]; - } -} - -// this function is designed to support animated gifs, although stb_image doesn't support it -static uint8 *stbi_gif_load_next(stbi *s, stbi_gif *g, int *comp, int req_comp) -{ - int i; - uint8 *old_out = 0; - - if (g->out == 0) { - if (!stbi_gif_header(s, g, comp,0)) return 0; // failure_reason set by stbi_gif_header - g->out = (uint8 *) malloc(4 * g->w * g->h); - if (g->out == 0) return epuc("outofmem", "Out of memory"); - stbi_fill_gif_background(g); - } else { - // animated-gif-only path - if (((g->eflags & 0x1C) >> 2) == 3) { - old_out = g->out; - g->out = (uint8 *) malloc(4 * g->w * g->h); - if (g->out == 0) return epuc("outofmem", "Out of memory"); - memcpy(g->out, old_out, g->w*g->h*4); - } - } - - for (;;) { - switch (get8(s)) { - case 0x2C: /* Image Descriptor */ - { - int32 x, y, w, h; - uint8 *o; - - x = get16le(s); - y = get16le(s); - w = get16le(s); - h = get16le(s); - if (((x + w) > (g->w)) || ((y + h) > (g->h))) - return epuc("bad Image Descriptor", "Corrupt GIF"); - - g->line_size = g->w * 4; - g->start_x = x * 4; - g->start_y = y * g->line_size; - g->max_x = g->start_x + w * 4; - g->max_y = g->start_y + h * g->line_size; - g->cur_x = g->start_x; - g->cur_y = g->start_y; - - g->lflags = get8(s); - - if (g->lflags & 0x40) { - g->step = 8 * g->line_size; // first interlaced spacing - g->parse = 3; - } else { - g->step = g->line_size; - g->parse = 0; - } - - if (g->lflags & 0x80) { - stbi_gif_parse_colortable(s,g->lpal, 2 << (g->lflags & 7), g->eflags & 0x01 ? g->transparent : -1); - g->color_table = (uint8 *) g->lpal; - } else if (g->flags & 0x80) { - for (i=0; i < 256; ++i) // @OPTIMIZE: reset only the previous transparent - g->pal[i][3] = 255; - if (g->transparent >= 0 && (g->eflags & 0x01)) - g->pal[g->transparent][3] = 0; - g->color_table = (uint8 *) g->pal; - } else - return epuc("missing color table", "Corrupt GIF"); - - o = stbi_process_gif_raster(s, g); - if (o == NULL) return NULL; - - if (req_comp && req_comp != 4) - o = convert_format(o, 4, req_comp, g->w, g->h); - return o; - } - - case 0x21: // Comment Extension. - { - int len; - if (get8(s) == 0xF9) { // Graphic Control Extension. - len = get8(s); - if (len == 4) { - g->eflags = get8(s); - get16le(s); // delay - g->transparent = get8(s); - } else { - skip(s, len); - break; - } - } - while ((len = get8(s)) != 0) - skip(s, len); - break; - } - - case 0x3B: // gif stream termination code - return (uint8 *) 1; - - default: - return epuc("unknown code", "Corrupt GIF"); - } - } -} - -static stbi_uc *stbi_gif_load(stbi *s, int *x, int *y, int *comp, int req_comp) -{ - uint8 *u = 0; - stbi_gif g={0}; - - u = stbi_gif_load_next(s, &g, comp, req_comp); - if (u == (void *) 1) u = 0; // end of animated gif marker - if (u) { - *x = g.w; - *y = g.h; - } - - return u; -} - -static int stbi_gif_info(stbi *s, int *x, int *y, int *comp) -{ - return stbi_gif_info_raw(s,x,y,comp); -} - - -// ************************************************************************************************* -// Radiance RGBE HDR loader -// originally by Nicolas Schulz -#ifndef STBI_NO_HDR -static int hdr_test(stbi *s) -{ - const char *signature = "#?RADIANCE\n"; - int i; - for (i=0; signature[i]; ++i) - if (get8(s) != signature[i]) - return 0; - return 1; -} - -static int stbi_hdr_test(stbi* s) -{ - int r = hdr_test(s); - stbi_rewind(s); - return r; -} - -#define HDR_BUFLEN 1024 -static char *hdr_gettoken(stbi *z, char *buffer) -{ - int len=0; - char c = '\0'; - - c = (char) get8(z); - - while (!at_eof(z) && c != '\n') { - buffer[len++] = c; - if (len == HDR_BUFLEN-1) { - // flush to end of line - while (!at_eof(z) && get8(z) != '\n') - ; - break; - } - c = (char) get8(z); - } - - buffer[len] = 0; - return buffer; -} - -static void hdr_convert(float *output, stbi_uc *input, int req_comp) -{ - if ( input[3] != 0 ) { - float f1; - // Exponent - f1 = (float) ldexp(1.0f, input[3] - (int)(128 + 8)); - if (req_comp <= 2) - output[0] = (input[0] + input[1] + input[2]) * f1 / 3; - else { - output[0] = input[0] * f1; - output[1] = input[1] * f1; - output[2] = input[2] * f1; - } - if (req_comp == 2) output[1] = 1; - if (req_comp == 4) output[3] = 1; - } else { - switch (req_comp) { - case 4: output[3] = 1; /* fallthrough */ - case 3: output[0] = output[1] = output[2] = 0; - break; - case 2: output[1] = 1; /* fallthrough */ - case 1: output[0] = 0; - break; - } - } -} - -static float *hdr_load(stbi *s, int *x, int *y, int *comp, int req_comp) -{ - char buffer[HDR_BUFLEN]; - char *token; - int valid = 0; - int width, height; - stbi_uc *scanline; - float *hdr_data; - int len; - unsigned char count, value; - int i, j, k, c1,c2, z; - - - // Check identifier - if (strcmp(hdr_gettoken(s,buffer), "#?RADIANCE") != 0) - return epf("not HDR", "Corrupt HDR image"); - - // Parse header - for(;;) { - token = hdr_gettoken(s,buffer); - if (token[0] == 0) break; - if (strcmp(token, "FORMAT=32-bit_rle_rgbe") == 0) valid = 1; - } - - if (!valid) return epf("unsupported format", "Unsupported HDR format"); - - // Parse width and height - // can't use sscanf() if we're not using stdio! - token = hdr_gettoken(s,buffer); - if (strncmp(token, "-Y ", 3)) return epf("unsupported data layout", "Unsupported HDR format"); - token += 3; - height = strtol(token, &token, 10); - while (*token == ' ') ++token; - if (strncmp(token, "+X ", 3)) return epf("unsupported data layout", "Unsupported HDR format"); - token += 3; - width = strtol(token, NULL, 10); - - *x = width; - *y = height; - - *comp = 3; - if (req_comp == 0) req_comp = 3; - - // Read data - hdr_data = (float *) malloc(height * width * req_comp * sizeof(float)); - - // Load image data - // image data is stored as some number of sca - if ( width < 8 || width >= 32768) { - // Read flat data - for (j=0; j < height; ++j) { - for (i=0; i < width; ++i) { - stbi_uc rgbe[4]; - main_decode_loop: - getn(s, rgbe, 4); - hdr_convert(hdr_data + j * width * req_comp + i * req_comp, rgbe, req_comp); - } - } - } else { - // Read RLE-encoded data - scanline = NULL; - - for (j = 0; j < height; ++j) { - c1 = get8(s); - c2 = get8(s); - len = get8(s); - if (c1 != 2 || c2 != 2 || (len & 0x80)) { - // not run-length encoded, so we have to actually use THIS data as a decoded - // pixel (note this can't be a valid pixel--one of RGB must be >= 128) - uint8 rgbe[4]; - rgbe[0] = (uint8) c1; - rgbe[1] = (uint8) c2; - rgbe[2] = (uint8) len; - rgbe[3] = (uint8) get8u(s); - hdr_convert(hdr_data, rgbe, req_comp); - i = 1; - j = 0; - free(scanline); - goto main_decode_loop; // yes, this makes no sense - } - len <<= 8; - len |= get8(s); - if (len != width) { free(hdr_data); free(scanline); return epf("invalid decoded scanline length", "corrupt HDR"); } - if (scanline == NULL) scanline = (stbi_uc *) malloc(width * 4); - - for (k = 0; k < 4; ++k) { - i = 0; - while (i < width) { - count = get8u(s); - if (count > 128) { - // Run - value = get8u(s); - count -= 128; - for (z = 0; z < count; ++z) - scanline[i++ * 4 + k] = value; - } else { - // Dump - for (z = 0; z < count; ++z) - scanline[i++ * 4 + k] = get8u(s); - } - } - } - for (i=0; i < width; ++i) - hdr_convert(hdr_data+(j*width + i)*req_comp, scanline + i*4, req_comp); - } - free(scanline); - } - - return hdr_data; -} - -static float *stbi_hdr_load(stbi *s, int *x, int *y, int *comp, int req_comp) -{ - return hdr_load(s,x,y,comp,req_comp); -} - -static int stbi_hdr_info(stbi *s, int *x, int *y, int *comp) -{ - char buffer[HDR_BUFLEN]; - char *token; - int valid = 0; - - if (strcmp(hdr_gettoken(s,buffer), "#?RADIANCE") != 0) { - stbi_rewind( s ); - return 0; - } - - for(;;) { - token = hdr_gettoken(s,buffer); - if (token[0] == 0) break; - if (strcmp(token, "FORMAT=32-bit_rle_rgbe") == 0) valid = 1; - } - - if (!valid) { - stbi_rewind( s ); - return 0; - } - token = hdr_gettoken(s,buffer); - if (strncmp(token, "-Y ", 3)) { - stbi_rewind( s ); - return 0; - } - token += 3; - *y = strtol(token, &token, 10); - while (*token == ' ') ++token; - if (strncmp(token, "+X ", 3)) { - stbi_rewind( s ); - return 0; - } - token += 3; - *x = strtol(token, NULL, 10); - *comp = 3; - return 1; -} -#endif // STBI_NO_HDR - -static int stbi_bmp_info(stbi *s, int *x, int *y, int *comp) -{ - int hsz; - if (get8(s) != 'B' || get8(s) != 'M') { - stbi_rewind( s ); - return 0; - } - skip(s,12); - hsz = get32le(s); - if (hsz != 12 && hsz != 40 && hsz != 56 && hsz != 108) { - stbi_rewind( s ); - return 0; - } - if (hsz == 12) { - *x = get16le(s); - *y = get16le(s); - } else { - *x = get32le(s); - *y = get32le(s); - } - if (get16le(s) != 1) { - stbi_rewind( s ); - return 0; - } - *comp = get16le(s) / 8; - return 1; -} - -static int stbi_psd_info(stbi *s, int *x, int *y, int *comp) -{ - int channelCount; - if (get32(s) != 0x38425053) { - stbi_rewind( s ); - return 0; - } - if (get16(s) != 1) { - stbi_rewind( s ); - return 0; - } - skip(s, 6); - channelCount = get16(s); - if (channelCount < 0 || channelCount > 16) { - stbi_rewind( s ); - return 0; - } - *y = get32(s); - *x = get32(s); - if (get16(s) != 8) { - stbi_rewind( s ); - return 0; - } - if (get16(s) != 3) { - stbi_rewind( s ); - return 0; - } - *comp = 4; - return 1; -} - -static int stbi_pic_info(stbi *s, int *x, int *y, int *comp) -{ - int act_comp=0,num_packets=0,chained; - pic_packet_t packets[10]; - - skip(s, 92); - - *x = get16(s); - *y = get16(s); - if (at_eof(s)) return 0; - if ( (*x) != 0 && (1 << 28) / (*x) < (*y)) { - stbi_rewind( s ); - return 0; - } - - skip(s, 8); - - do { - pic_packet_t *packet; - - if (num_packets==sizeof(packets)/sizeof(packets[0])) - return 0; - - packet = &packets[num_packets++]; - chained = get8(s); - packet->size = get8u(s); - packet->type = get8u(s); - packet->channel = get8u(s); - act_comp |= packet->channel; - - if (at_eof(s)) { - stbi_rewind( s ); - return 0; - } - if (packet->size != 8) { - stbi_rewind( s ); - return 0; - } - } while (chained); - - *comp = (act_comp & 0x10 ? 4 : 3); - - return 1; -} - -static int stbi_info_main(stbi *s, int *x, int *y, int *comp) -{ - if (stbi_jpeg_info(s, x, y, comp)) - return 1; - if (stbi_png_info(s, x, y, comp)) - return 1; - if (stbi_gif_info(s, x, y, comp)) - return 1; - if (stbi_bmp_info(s, x, y, comp)) - return 1; - if (stbi_psd_info(s, x, y, comp)) - return 1; - if (stbi_pic_info(s, x, y, comp)) - return 1; - #ifndef STBI_NO_HDR - if (stbi_hdr_info(s, x, y, comp)) - return 1; - #endif - // test tga last because it's a crappy test! - if (stbi_tga_info(s, x, y, comp)) - return 1; - return e("unknown image type", "Image not of any known type, or corrupt"); -} - -#ifndef STBI_NO_STDIO -int stbi_info(char const *filename, int *x, int *y, int *comp) -{ - FILE *f = fopen(filename, "rb"); - int result; - if (!f) return e("can't fopen", "Unable to open file"); - result = stbi_info_from_file(f, x, y, comp); - fclose(f); - return result; -} - -int stbi_info_from_file(FILE *f, int *x, int *y, int *comp) -{ - int r; - stbi s; - long pos = ftell(f); - start_file(&s, f); - r = stbi_info_main(&s,x,y,comp); - fseek(f,pos,SEEK_SET); - return r; -} -#endif // !STBI_NO_STDIO - -int stbi_info_from_memory(stbi_uc const *buffer, int len, int *x, int *y, int *comp) -{ - stbi s; - start_mem(&s,buffer,len); - return stbi_info_main(&s,x,y,comp); -} - -int stbi_info_from_callbacks(stbi_io_callbacks const *c, void *user, int *x, int *y, int *comp) -{ - stbi s; - start_callbacks(&s, (stbi_io_callbacks *) c, user); - return stbi_info_main(&s,x,y,comp); -} - -#endif // STBI_HEADER_FILE_ONLY - -/* - revision history: - 1.34 - use STBI_NOTUSED in resample_row_generic() - 1.33 (2011-07-14) - make stbi_is_hdr work in STBI_NO_HDR (as specified), minor compiler-friendly improvements - 1.32 (2011-07-13) - support for "info" function for all supported filetypes (SpartanJ) - 1.31 (2011-06-20) - a few more leak fixes, bug in PNG handling (SpartanJ) - 1.30 (2011-06-11) - added ability to load files via callbacks to accomidate custom input streams (Ben Wenger) - removed deprecated format-specific test/load functions - removed support for installable file formats (stbi_loader) -- would have been broken for IO callbacks anyway - error cases in bmp and tga give messages and don't leak (Raymond Barbiero, grisha) - fix inefficiency in decoding 32-bit BMP (David Woo) - 1.29 (2010-08-16) - various warning fixes from Aurelien Pocheville - 1.28 (2010-08-01) - fix bug in GIF palette transparency (SpartanJ) - 1.27 (2010-08-01) - cast-to-uint8 to fix warnings - 1.26 (2010-07-24) - fix bug in file buffering for PNG reported by SpartanJ - 1.25 (2010-07-17) - refix trans_data warning (Won Chun) - 1.24 (2010-07-12) - perf improvements reading from files on platforms with lock-heavy fgetc() - minor perf improvements for jpeg - deprecated type-specific functions so we'll get feedback if they're needed - attempt to fix trans_data warning (Won Chun) - 1.23 fixed bug in iPhone support - 1.22 (2010-07-10) - removed image *writing* support - stbi_info support from Jetro Lauha - GIF support from Jean-Marc Lienher - iPhone PNG-extensions from James Brown - warning-fixes from Nicolas Schulz and Janez Zemva (i.e. Janez (U+017D)emva) - 1.21 fix use of 'uint8' in header (reported by jon blow) - 1.20 added support for Softimage PIC, by Tom Seddon - 1.19 bug in interlaced PNG corruption check (found by ryg) - 1.18 2008-08-02 - fix a threading bug (local mutable static) - 1.17 support interlaced PNG - 1.16 major bugfix - convert_format converted one too many pixels - 1.15 initialize some fields for thread safety - 1.14 fix threadsafe conversion bug - header-file-only version (#define STBI_HEADER_FILE_ONLY before including) - 1.13 threadsafe - 1.12 const qualifiers in the API - 1.11 Support installable IDCT, colorspace conversion routines - 1.10 Fixes for 64-bit (don't use "unsigned long") - optimized upsampling by Fabian "ryg" Giesen - 1.09 Fix format-conversion for PSD code (bad global variables!) - 1.08 Thatcher Ulrich's PSD code integrated by Nicolas Schulz - 1.07 attempt to fix C++ warning/errors again - 1.06 attempt to fix C++ warning/errors again - 1.05 fix TGA loading to return correct *comp and use good luminance calc - 1.04 default float alpha is 1, not 255; use 'void *' for stbi_image_free - 1.03 bugfixes to STBI_NO_STDIO, STBI_NO_HDR - 1.02 support for (subset of) HDR files, float interface for preferred access to them - 1.01 fix bug: possible bug in handling right-side up bmps... not sure - fix bug: the stbi_bmp_load() and stbi_tga_load() functions didn't work at all - 1.00 interface to zlib that skips zlib header - 0.99 correct handling of alpha in palette - 0.98 TGA loader by lonesock; dynamically add loaders (untested) - 0.97 jpeg errors on too large a file; also catch another malloc failure - 0.96 fix detection of invalid v value - particleman@mollyrocket forum - 0.95 during header scan, seek to markers in case of padding - 0.94 STBI_NO_STDIO to disable stdio usage; rename all #defines the same - 0.93 handle jpegtran output; verbose errors - 0.92 read 4,8,16,24,32-bit BMP files of several formats - 0.91 output 24-bit Windows 3.0 BMP files - 0.90 fix a few more warnings; bump version number to approach 1.0 - 0.61 bugfixes due to Marc LeBlanc, Christopher Lloyd - 0.60 fix compiling as c++ - 0.59 fix warnings: merge Dave Moore's -Wall fixes - 0.58 fix bug: zlib uncompressed mode len/nlen was wrong endian - 0.57 fix bug: jpg last huffman symbol before marker was >9 bits but less than 16 available - 0.56 fix bug: zlib uncompressed mode len vs. nlen - 0.55 fix bug: restart_interval not initialized to 0 - 0.54 allow NULL for 'int *comp' - 0.53 fix bug in png 3->4; speedup png decoding - 0.52 png handles req_comp=3,4 directly; minor cleanup; jpeg comments - 0.51 obey req_comp requests, 1-component jpegs return as 1-component, - on 'test' only check type, not whether we support this variant - 0.50 first released version -*/ diff --git a/stblib/stb_image.h b/stblib/stb_image.h index 70c043ecf5..499cdeadd3 100644 --- a/stblib/stb_image.h +++ b/stblib/stb_image.h @@ -1,82 +1,236 @@ -/* stbi-1.33 - public domain JPEG/PNG reader - http://nothings.org/stb_image.c - when you control the images you're loading - no warranty implied; use at your own risk +/* stb_image - v2.10 - public domain image loader - http://nothings.org/stb_image.h +no warranty implied; use at your own risk - QUICK NOTES: - Primarily of interest to game developers and other people who can - avoid problematic images and only need the trivial interface +Do this: +#define STB_IMAGE_IMPLEMENTATION +before you include this file in *one* C or C++ file to create the implementation. - JPEG baseline (no JPEG progressive) - PNG 8-bit only +// i.e. it should look like this: +#include ... +#include ... +#include ... +#define STB_IMAGE_IMPLEMENTATION +#include "stb_image.h" - TGA (not sure what subset, if a subset) - BMP non-1bpp, non-RLE - PSD (composited view only, no extra channels) - - GIF (*comp always reports as 4-channel) - HDR (radiance rgbE format) - PIC (Softimage PIC) - - - decode from memory or through FILE (define STBI_NO_STDIO to remove code) - - decode from arbitrary I/O callbacks - - overridable dequantizing-IDCT, YCbCr-to-RGB conversion (define STBI_SIMD) - - Latest revisions: - 1.33 (2011-07-14) minor fixes suggested by Dave Moore - 1.32 (2011-07-13) info support for all filetypes (SpartanJ) - 1.31 (2011-06-19) a few more leak fixes, bug in PNG handling (SpartanJ) - 1.30 (2011-06-11) added ability to load files via io callbacks (Ben Wenger) - 1.29 (2010-08-16) various warning fixes from Aurelien Pocheville - - See end of file for full revision history. - - TODO: - stbi_info support for BMP,PSD,HDR,PIC +You can #define STBI_ASSERT(x) before the #include to avoid using assert.h. +And #define STBI_MALLOC, STBI_REALLOC, and STBI_FREE to avoid using malloc,realloc,free - ============================ Contributors ========================= - - Image formats Optimizations & bugfixes - Sean Barrett (jpeg, png, bmp) Fabian "ryg" Giesen - Nicolas Schulz (hdr, psd) - Jonathan Dummer (tga) Bug fixes & warning fixes - Jean-Marc Lienher (gif) Marc LeBlanc - Tom Seddon (pic) Christpher Lloyd - Thatcher Ulrich (psd) Dave Moore - Won Chun - the Horde3D community - Extensions, features Janez Zemva - Jetro Lauha (stbi_info) Jonathan Blow - James "moose2000" Brown (iPhone PNG) Laurent Gomila - Ben "Disch" Wenger (io callbacks) Aruelien Pocheville - Martin "SpartanJ" Golini Ryamond Barbiero - David Woo - +QUICK NOTES: +Primarily of interest to game developers and other people who can +avoid problematic images and only need the trivial interface - If your name should be here but isn't, let Sean know. +JPEG baseline & progressive (12 bpc/arithmetic not supported, same as stock IJG lib) +PNG 1/2/4/8-bit-per-channel (16 bpc not supported) + +TGA (not sure what subset, if a subset) +BMP non-1bpp, non-RLE +PSD (composited view only, no extra channels, 8/16 bit-per-channel) + +GIF (*comp always reports as 4-channel) +HDR (radiance rgbE format) +PIC (Softimage PIC) +PNM (PPM and PGM binary only) + +Animated GIF still needs a proper API, but here's one way to do it: +http://gist.github.com/urraka/685d9a6340b26b830d49 + +- decode from memory or through FILE (define STBI_NO_STDIO to remove code) +- decode from arbitrary I/O callbacks +- SIMD acceleration on x86/x64 (SSE2) and ARM (NEON) + +Full documentation under "DOCUMENTATION" below. + + +Revision 2.00 release notes: + +- Progressive JPEG is now supported. + +- PPM and PGM binary formats are now supported, thanks to Ken Miller. + +- x86 platforms now make use of SSE2 SIMD instructions for +JPEG decoding, and ARM platforms can use NEON SIMD if requested. +This work was done by Fabian "ryg" Giesen. SSE2 is used by +default, but NEON must be enabled explicitly; see docs. + +With other JPEG optimizations included in this version, we see +2x speedup on a JPEG on an x86 machine, and a 1.5x speedup +on a JPEG on an ARM machine, relative to previous versions of this +library. The same results will not obtain for all JPGs and for all +x86/ARM machines. (Note that progressive JPEGs are significantly +slower to decode than regular JPEGs.) This doesn't mean that this +is the fastest JPEG decoder in the land; rather, it brings it +closer to parity with standard libraries. If you want the fastest +decode, look elsewhere. (See "Philosophy" section of docs below.) + +See final bullet items below for more info on SIMD. + +- Added STBI_MALLOC, STBI_REALLOC, and STBI_FREE macros for replacing +the memory allocator. Unlike other STBI libraries, these macros don't +support a context parameter, so if you need to pass a context in to +the allocator, you'll have to store it in a global or a thread-local +variable. + +- Split existing STBI_NO_HDR flag into two flags, STBI_NO_HDR and +STBI_NO_LINEAR. +STBI_NO_HDR: suppress implementation of .hdr reader format +STBI_NO_LINEAR: suppress high-dynamic-range light-linear float API + +- You can suppress implementation of any of the decoders to reduce +your code footprint by #defining one or more of the following +symbols before creating the implementation. + +STBI_NO_JPEG +STBI_NO_PNG +STBI_NO_BMP +STBI_NO_PSD +STBI_NO_TGA +STBI_NO_GIF +STBI_NO_HDR +STBI_NO_PIC +STBI_NO_PNM (.ppm and .pgm) + +- You can request *only* certain decoders and suppress all other ones +(this will be more forward-compatible, as addition of new decoders +doesn't require you to disable them explicitly): + +STBI_ONLY_JPEG +STBI_ONLY_PNG +STBI_ONLY_BMP +STBI_ONLY_PSD +STBI_ONLY_TGA +STBI_ONLY_GIF +STBI_ONLY_HDR +STBI_ONLY_PIC +STBI_ONLY_PNM (.ppm and .pgm) + +Note that you can define multiples of these, and you will get all +of them ("only x" and "only y" is interpreted to mean "only x&y"). + +- If you use STBI_NO_PNG (or _ONLY_ without PNG), and you still +want the zlib decoder to be available, #define STBI_SUPPORT_ZLIB + +- Compilation of all SIMD code can be suppressed with +#define STBI_NO_SIMD +It should not be necessary to disable SIMD unless you have issues +compiling (e.g. using an x86 compiler which doesn't support SSE +intrinsics or that doesn't support the method used to detect +SSE2 support at run-time), and even those can be reported as +bugs so I can refine the built-in compile-time checking to be +smarter. + +- The old STBI_SIMD system which allowed installing a user-defined +IDCT etc. has been removed. If you need this, don't upgrade. My +assumption is that almost nobody was doing this, and those who +were will find the built-in SIMD more satisfactory anyway. + +- RGB values computed for JPEG images are slightly different from +previous versions of stb_image. (This is due to using less +integer precision in SIMD.) The C code has been adjusted so +that the same RGB values will be computed regardless of whether +SIMD support is available, so your app should always produce +consistent results. But these results are slightly different from +previous versions. (Specifically, about 3% of available YCbCr values +will compute different RGB results from pre-1.49 versions by +-1; +most of the deviating values are one smaller in the G channel.) + +- If you must produce consistent results with previous versions of +stb_image, #define STBI_JPEG_OLD and you will get the same results +you used to; however, you will not get the SIMD speedups for +the YCbCr-to-RGB conversion step (although you should still see +significant JPEG speedup from the other changes). + +Please note that STBI_JPEG_OLD is a temporary feature; it will be +removed in future versions of the library. It is only intended for +near-term back-compatibility use. + + +Latest revision history: +2.10 (2016-01-22) avoid warning introduced in 2.09 +2.09 (2016-01-16) 16-bit TGA; comments in PNM files; STBI_REALLOC_SIZED +2.08 (2015-09-13) fix to 2.07 cleanup, reading RGB PSD as RGBA +2.07 (2015-09-13) partial animated GIF support +limited 16-bit PSD support +minor bugs, code cleanup, and compiler warnings +2.06 (2015-04-19) fix bug where PSD returns wrong '*comp' value +2.05 (2015-04-19) fix bug in progressive JPEG handling, fix warning +2.04 (2015-04-15) try to re-enable SIMD on MinGW 64-bit +2.03 (2015-04-12) additional corruption checking +stbi_set_flip_vertically_on_load +fix NEON support; fix mingw support +2.02 (2015-01-19) fix incorrect assert, fix warning +2.01 (2015-01-17) fix various warnings +2.00b (2014-12-25) fix STBI_MALLOC in progressive JPEG +2.00 (2014-12-25) optimize JPEG, including x86 SSE2 & ARM NEON SIMD +progressive JPEG +PGM/PPM support +STBI_MALLOC,STBI_REALLOC,STBI_FREE +STBI_NO_*, STBI_ONLY_* +GIF bugfix +1.48 (2014-12-14) fix incorrectly-named assert() +1.47 (2014-12-14) 1/2/4-bit PNG support (both grayscale and paletted) +optimize PNG +fix bug in interlaced PNG with user-specified channel count + +See end of file for full revision history. + + +============================ Contributors ========================= + +Image formats Extensions, features +Sean Barrett (jpeg, png, bmp) Jetro Lauha (stbi_info) +Nicolas Schulz (hdr, psd) Martin "SpartanJ" Golini (stbi_info) +Jonathan Dummer (tga) James "moose2000" Brown (iPhone PNG) +Jean-Marc Lienher (gif) Ben "Disch" Wenger (io callbacks) +Tom Seddon (pic) Omar Cornut (1/2/4-bit PNG) +Thatcher Ulrich (psd) Nicolas Guillemot (vertical flip) +Ken Miller (pgm, ppm) Richard Mitton (16-bit PSD) +urraka@github (animated gif) Junggon Kim (PNM comments) +Daniel Gibson (16-bit TGA) + +Optimizations & bugfixes +Fabian "ryg" Giesen +Arseny Kapoulkine + +Bug & warning fixes +Marc LeBlanc David Woo Guillaume George Martins Mozeiko +Christpher Lloyd Martin Golini Jerry Jansson Joseph Thomson +Dave Moore Roy Eltham Hayaki Saito Phil Jordan +Won Chun Luke Graham Johan Duparc Nathan Reed +the Horde3D community Thomas Ruf Ronny Chevalier Nick Verigakis +Janez Zemva John Bartholomew Michal Cichon svdijk@github +Jonathan Blow Ken Hamada Tero Hanninen Baldur Karlsson +Laurent Gomila Cort Stratton Sergio Gonzalez romigrou@github +Aruelien Pocheville Thibault Reuille Cass Everitt +Ryamond Barbiero Paul Du Bois Engin Manap +Blazej Dariusz Roszkowski +Michaelangel007@github + + +LICENSE + +This software is in the public domain. Where that dedication is not +recognized, you are granted a perpetual, irrevocable license to copy, +distribute, and modify this file as you see fit. */ #ifndef STBI_INCLUDE_STB_IMAGE_H #define STBI_INCLUDE_STB_IMAGE_H -// To get a header file for this, either cut and paste the header, -// or create stb_image.h, #define STBI_HEADER_FILE_ONLY, and -// then include stb_image.c from it. - -//// begin header file //////////////////////////////////////////////////// +// DOCUMENTATION // // Limitations: -// - no jpeg progressive support -// - non-HDR formats support 8-bit samples only (jpeg, png) -// - no delayed line count (jpeg) -- IJG doesn't support either +// - no 16-bit-per-channel PNG +// - no 12-bit-per-channel JPEG +// - no JPEGs with arithmetic coding // - no 1-bit BMP // - GIF always returns *comp=4 // -// Basic usage (see HDR discussion below): +// Basic usage (see HDR discussion below for HDR usage): // int x,y,n; // unsigned char *data = stbi_load(filename, &x, &y, &n, 0); -// // ... process data if not NULL ... +// // ... process data if not NULL ... // // ... x = width, y = height, n = # 8-bit components per pixel ... // // ... replace '0' with '1'..'4' to force that many components per pixel // // ... but 'n' will always be the number that it would have been if you said 0 @@ -89,14 +243,16 @@ // int req_comp -- if non-zero, # of image components requested in result // // The return value from an image loader is an 'unsigned char *' which points -// to the pixel data. The pixel data consists of *y scanlines of *x pixels, +// to the pixel data, or NULL on an allocation failure or if the image is +// corrupt or invalid. The pixel data consists of *y scanlines of *x pixels, // with each pixel consisting of N interleaved 8-bit components; the first // pixel pointed to is top-left-most in the image. There is no padding between // image scanlines or between pixels, regardless of format. The number of // components N is 'req_comp' if req_comp is non-zero, or *comp otherwise. // If req_comp is non-zero, *comp has the number of components that _would_ // have been output otherwise. E.g. if you set req_comp to 4, you will always -// get RGBA output, but you can check *comp to easily see if it's opaque. +// get RGBA output, but you can check *comp to see if it's trivially opaque +// because e.g. there were only 3 channels in the source image. // // An output image with N components has the following components interleaved // in this order in each pixel: @@ -118,18 +274,66 @@ // // =========================================================================== // -// iPhone PNG support: +// Philosophy // -// By default we convert iphone-formatted PNGs back to RGB; nominally they -// would silently load as BGR, except the existing code should have just -// failed on such iPhone PNGs. But you can disable this conversion by -// by calling stbi_convert_iphone_png_to_rgb(0), in which case -// you will always just get the native iphone "format" through. +// stb libraries are designed with the following priorities: // -// Call stbi_set_unpremultiply_on_load(1) as well to force a divide per -// pixel to remove any premultiplied alpha *only* if the image file explicitly -// says there's premultiplied data (currently only happens in iPhone images, -// and only if iPhone convert-to-rgb processing is on). +// 1. easy to use +// 2. easy to maintain +// 3. good performance +// +// Sometimes I let "good performance" creep up in priority over "easy to maintain", +// and for best performance I may provide less-easy-to-use APIs that give higher +// performance, in addition to the easy to use ones. Nevertheless, it's important +// to keep in mind that from the standpoint of you, a client of this library, +// all you care about is #1 and #3, and stb libraries do not emphasize #3 above all. +// +// Some secondary priorities arise directly from the first two, some of which +// make more explicit reasons why performance can't be emphasized. +// +// - Portable ("ease of use") +// - Small footprint ("easy to maintain") +// - No dependencies ("ease of use") +// +// =========================================================================== +// +// I/O callbacks +// +// I/O callbacks allow you to read from arbitrary sources, like packaged +// files or some other source. Data read from callbacks are processed +// through a small internal buffer (currently 128 bytes) to try to reduce +// overhead. +// +// The three functions you must define are "read" (reads some bytes of data), +// "skip" (skips some bytes of data), "eof" (reports if the stream is at the end). +// +// =========================================================================== +// +// SIMD support +// +// The JPEG decoder will try to automatically use SIMD kernels on x86 when +// supported by the compiler. For ARM Neon support, you must explicitly +// request it. +// +// (The old do-it-yourself SIMD API is no longer supported in the current +// code.) +// +// On x86, SSE2 will automatically be used when available based on a run-time +// test; if not, the generic C versions are used as a fall-back. On ARM targets, +// the typical path is to have separate builds for NEON and non-NEON devices +// (at least this is true for iOS and Android). Therefore, the NEON support is +// toggled by a build flag: define STBI_NEON to get NEON loops. +// +// The output of the JPEG decoder is slightly different from versions where +// SIMD support was introduced (that is, for versions before 1.49). The +// difference is only +-1 in the 8-bit RGB channels, and only on a small +// fraction of pixels. You can force the pre-1.49 behavior by defining +// STBI_JPEG_OLD, but this will disable some of the SIMD decoding path +// and hence cost some performance. +// +// If for some reason you do not want to use any of SIMD code, or if +// you have issues compiling it, you can disable it entirely by +// defining STBI_NO_SIMD. // // =========================================================================== // @@ -152,7 +356,7 @@ // (linear) floats to preserve the full dynamic range: // // float *data = stbi_loadf(filename, &x, &y, &n, 0); -// +// // If you load LDR images through this interface, those images will // be promoted to floating point values, run through the inverse of // constants corresponding to the above: @@ -169,36 +373,35 @@ // // =========================================================================== // -// I/O callbacks +// iPhone PNG support: // -// I/O callbacks allow you to read from arbitrary sources, like packaged -// files or some other source. Data read from callbacks are processed -// through a small internal buffer (currently 128 bytes) to try to reduce -// overhead. +// By default we convert iphone-formatted PNGs back to RGB, even though +// they are internally encoded differently. You can disable this conversion +// by by calling stbi_convert_iphone_png_to_rgb(0), in which case +// you will always just get the native iphone "format" through (which +// is BGR stored in RGB). +// +// Call stbi_set_unpremultiply_on_load(1) as well to force a divide per +// pixel to remove any premultiplied alpha *only* if the image file explicitly +// says there's premultiplied data (currently only happens in iPhone images, +// and only if iPhone convert-to-rgb processing is on). // -// The three functions you must define are "read" (reads some bytes of data), -// "skip" (skips some bytes of data), "eof" (reports if the stream is at the end). #ifndef STBI_NO_STDIO - -#if defined(_MSC_VER) && _MSC_VER >= 0x1400 -#define _CRT_SECURE_NO_WARNINGS // suppress bogus warnings about fopen() -#endif - #include -#endif +#endif // STBI_NO_STDIO #define STBI_VERSION 1 enum { - STBI_default = 0, // only used for req_comp + STBI_default = 0, // only used for req_comp - STBI_grey = 1, - STBI_grey_alpha = 2, - STBI_rgb = 3, - STBI_rgb_alpha = 4 + STBI_grey = 1, + STBI_grey_alpha = 2, + STBI_rgb = 3, + STBI_rgb_alpha = 4 }; typedef unsigned char stbi_uc; @@ -207,115 +410,106 @@ typedef unsigned char stbi_uc; extern "C" { #endif -////////////////////////////////////////////////////////////////////////////// -// -// PRIMARY API - works on images of any type -// - -// -// load image by filename, open file, or memory buffer -// - -extern stbi_uc *stbi_load_from_memory(stbi_uc const *buffer, int len, int *x, int *y, int *comp, int req_comp); - -#ifndef STBI_NO_STDIO -extern stbi_uc *stbi_load (char const *filename, int *x, int *y, int *comp, int req_comp); -extern stbi_uc *stbi_load_from_file (FILE *f, int *x, int *y, int *comp, int req_comp); -// for stbi_load_from_file, file pointer is left pointing immediately after image +#ifdef STB_IMAGE_STATIC +#define STBIDEF static +#else +#define STBIDEF extern #endif -typedef struct -{ - int (*read) (void *user,char *data,int size); // fill 'data' with 'size' bytes. return number of bytes actually read - void (*skip) (void *user,unsigned n); // skip the next 'n' bytes - int (*eof) (void *user); // returns nonzero if we are at end of file/data -} stbi_io_callbacks; + ////////////////////////////////////////////////////////////////////////////// + // + // PRIMARY API - works on images of any type + // -extern stbi_uc *stbi_load_from_callbacks (stbi_io_callbacks const *clbk, void *user, int *x, int *y, int *comp, int req_comp); + // + // load image by filename, open file, or memory buffer + // + + typedef struct + { + int(*read) (void *user, char *data, int size); // fill 'data' with 'size' bytes. return number of bytes actually read + void(*skip) (void *user, int n); // skip the next 'n' bytes, or 'unget' the last -n bytes if negative + int(*eof) (void *user); // returns nonzero if we are at end of file/data + } stbi_io_callbacks; + + STBIDEF stbi_uc *stbi_load(char const *filename, int *x, int *y, int *comp, int req_comp); + STBIDEF stbi_uc *stbi_load_from_memory(stbi_uc const *buffer, int len, int *x, int *y, int *comp, int req_comp); + STBIDEF stbi_uc *stbi_load_from_callbacks(stbi_io_callbacks const *clbk, void *user, int *x, int *y, int *comp, int req_comp); + +#ifndef STBI_NO_STDIO + STBIDEF stbi_uc *stbi_load_from_file(FILE *f, int *x, int *y, int *comp, int req_comp); + // for stbi_load_from_file, file pointer is left pointing immediately after image +#endif + +#ifndef STBI_NO_LINEAR + STBIDEF float *stbi_loadf(char const *filename, int *x, int *y, int *comp, int req_comp); + STBIDEF float *stbi_loadf_from_memory(stbi_uc const *buffer, int len, int *x, int *y, int *comp, int req_comp); + STBIDEF float *stbi_loadf_from_callbacks(stbi_io_callbacks const *clbk, void *user, int *x, int *y, int *comp, int req_comp); + +#ifndef STBI_NO_STDIO + STBIDEF float *stbi_loadf_from_file(FILE *f, int *x, int *y, int *comp, int req_comp); +#endif +#endif #ifndef STBI_NO_HDR - extern float *stbi_loadf_from_memory(stbi_uc const *buffer, int len, int *x, int *y, int *comp, int req_comp); - - #ifndef STBI_NO_STDIO - extern float *stbi_loadf (char const *filename, int *x, int *y, int *comp, int req_comp); - extern float *stbi_loadf_from_file (FILE *f, int *x, int *y, int *comp, int req_comp); - #endif - - extern float *stbi_loadf_from_callbacks (stbi_io_callbacks const *clbk, void *user, int *x, int *y, int *comp, int req_comp); - - extern void stbi_hdr_to_ldr_gamma(float gamma); - extern void stbi_hdr_to_ldr_scale(float scale); - - extern void stbi_ldr_to_hdr_gamma(float gamma); - extern void stbi_ldr_to_hdr_scale(float scale); + STBIDEF void stbi_hdr_to_ldr_gamma(float gamma); + STBIDEF void stbi_hdr_to_ldr_scale(float scale); #endif // STBI_NO_HDR -// stbi_is_hdr is always defined -extern int stbi_is_hdr_from_callbacks(stbi_io_callbacks const *clbk, void *user); -extern int stbi_is_hdr_from_memory(stbi_uc const *buffer, int len); +#ifndef STBI_NO_LINEAR + STBIDEF void stbi_ldr_to_hdr_gamma(float gamma); + STBIDEF void stbi_ldr_to_hdr_scale(float scale); +#endif // STBI_NO_LINEAR + + // stbi_is_hdr is always defined, but always returns false if STBI_NO_HDR + STBIDEF int stbi_is_hdr_from_callbacks(stbi_io_callbacks const *clbk, void *user); + STBIDEF int stbi_is_hdr_from_memory(stbi_uc const *buffer, int len); #ifndef STBI_NO_STDIO -extern int stbi_is_hdr (char const *filename); -extern int stbi_is_hdr_from_file(FILE *f); + STBIDEF int stbi_is_hdr(char const *filename); + STBIDEF int stbi_is_hdr_from_file(FILE *f); #endif // STBI_NO_STDIO -// get a VERY brief reason for failure -// NOT THREADSAFE -extern const char *stbi_failure_reason (void); + // get a VERY brief reason for failure + // NOT THREADSAFE + STBIDEF const char *stbi_failure_reason(void); -// free the loaded image -- this is just free() -extern void stbi_image_free (void *retval_from_stbi_load); + // free the loaded image -- this is just free() + STBIDEF void stbi_image_free(void *retval_from_stbi_load); -// get image dimensions & components without fully decoding -extern int stbi_info_from_memory(stbi_uc const *buffer, int len, int *x, int *y, int *comp); -extern int stbi_info_from_callbacks(stbi_io_callbacks const *clbk, void *user, int *x, int *y, int *comp); + // get image dimensions & components without fully decoding + STBIDEF int stbi_info_from_memory(stbi_uc const *buffer, int len, int *x, int *y, int *comp); + STBIDEF int stbi_info_from_callbacks(stbi_io_callbacks const *clbk, void *user, int *x, int *y, int *comp); #ifndef STBI_NO_STDIO -extern int stbi_info (char const *filename, int *x, int *y, int *comp); -extern int stbi_info_from_file (FILE *f, int *x, int *y, int *comp); + STBIDEF int stbi_info(char const *filename, int *x, int *y, int *comp); + STBIDEF int stbi_info_from_file(FILE *f, int *x, int *y, int *comp); #endif -// for image formats that explicitly notate that they have premultiplied alpha, -// we just return the colors as stored in the file. set this flag to force -// unpremultiplication. results are undefined if the unpremultiply overflow. -extern void stbi_set_unpremultiply_on_load(int flag_true_if_should_unpremultiply); + // for image formats that explicitly notate that they have premultiplied alpha, + // we just return the colors as stored in the file. set this flag to force + // unpremultiplication. results are undefined if the unpremultiply overflow. + STBIDEF void stbi_set_unpremultiply_on_load(int flag_true_if_should_unpremultiply); -// indicate whether we should process iphone images back to canonical format, -// or just pass them through "as-is" -extern void stbi_convert_iphone_png_to_rgb(int flag_true_if_should_convert); + // indicate whether we should process iphone images back to canonical format, + // or just pass them through "as-is" + STBIDEF void stbi_convert_iphone_png_to_rgb(int flag_true_if_should_convert); + // flip the image vertically, so the first pixel in the output array is the bottom left + STBIDEF void stbi_set_flip_vertically_on_load(int flag_true_if_should_flip); -// ZLIB client - used by PNG, available for other purposes + // ZLIB client - used by PNG, available for other purposes -extern char *stbi_zlib_decode_malloc_guesssize(const char *buffer, int len, int initial_size, int *outlen); -extern char *stbi_zlib_decode_malloc(const char *buffer, int len, int *outlen); -extern int stbi_zlib_decode_buffer(char *obuffer, int olen, const char *ibuffer, int ilen); + STBIDEF char *stbi_zlib_decode_malloc_guesssize(const char *buffer, int len, int initial_size, int *outlen); + STBIDEF char *stbi_zlib_decode_malloc_guesssize_headerflag(const char *buffer, int len, int initial_size, int *outlen, int parse_header); + STBIDEF char *stbi_zlib_decode_malloc(const char *buffer, int len, int *outlen); + STBIDEF int stbi_zlib_decode_buffer(char *obuffer, int olen, const char *ibuffer, int ilen); -extern char *stbi_zlib_decode_noheader_malloc(const char *buffer, int len, int *outlen); -extern int stbi_zlib_decode_noheader_buffer(char *obuffer, int olen, const char *ibuffer, int ilen); - - -// define faster low-level operations (typically SIMD support) -#ifdef STBI_SIMD -typedef void (*stbi_idct_8x8)(stbi_uc *out, int out_stride, short data[64], unsigned short *dequantize); -// compute an integer IDCT on "input" -// input[x] = data[x] * dequantize[x] -// write results to 'out': 64 samples, each run of 8 spaced by 'out_stride' -// CLAMP results to 0..255 -typedef void (*stbi_YCbCr_to_RGB_run)(stbi_uc *output, stbi_uc const *y, stbi_uc const *cb, stbi_uc const *cr, int count, int step); -// compute a conversion from YCbCr to RGB -// 'count' pixels -// write pixels to 'output'; each pixel is 'step' bytes (either 3 or 4; if 4, write '255' as 4th), order R,G,B -// y: Y input channel -// cb: Cb input channel; scale/biased to be 0..255 -// cr: Cr input channel; scale/biased to be 0..255 - -extern void stbi_install_idct(stbi_idct_8x8 func); -extern void stbi_install_YCbCr_to_RGB(stbi_YCbCr_to_RGB_run func); -#endif // STBI_SIMD + STBIDEF char *stbi_zlib_decode_noheader_malloc(const char *buffer, int len, int *outlen); + STBIDEF int stbi_zlib_decode_noheader_buffer(char *obuffer, int olen, const char *ibuffer, int ilen); #ifdef __cplusplus @@ -327,3 +521,6178 @@ extern void stbi_install_YCbCr_to_RGB(stbi_YCbCr_to_RGB_run func); //// end header file ///////////////////////////////////////////////////// #endif // STBI_INCLUDE_STB_IMAGE_H +#ifdef STB_IMAGE_IMPLEMENTATION + +#if defined(STBI_ONLY_JPEG) || defined(STBI_ONLY_PNG) || defined(STBI_ONLY_BMP) \ + || defined(STBI_ONLY_TGA) || defined(STBI_ONLY_GIF) || defined(STBI_ONLY_PSD) \ + || defined(STBI_ONLY_HDR) || defined(STBI_ONLY_PIC) || defined(STBI_ONLY_PNM) \ + || defined(STBI_ONLY_ZLIB) +#ifndef STBI_ONLY_JPEG +#define STBI_NO_JPEG +#endif +#ifndef STBI_ONLY_PNG +#define STBI_NO_PNG +#endif +#ifndef STBI_ONLY_BMP +#define STBI_NO_BMP +#endif +#ifndef STBI_ONLY_PSD +#define STBI_NO_PSD +#endif +#ifndef STBI_ONLY_TGA +#define STBI_NO_TGA +#endif +#ifndef STBI_ONLY_GIF +#define STBI_NO_GIF +#endif +#ifndef STBI_ONLY_HDR +#define STBI_NO_HDR +#endif +#ifndef STBI_ONLY_PIC +#define STBI_NO_PIC +#endif +#ifndef STBI_ONLY_PNM +#define STBI_NO_PNM +#endif +#endif + +#if defined(STBI_NO_PNG) && !defined(STBI_SUPPORT_ZLIB) && !defined(STBI_NO_ZLIB) +#define STBI_NO_ZLIB +#endif + + +#include +#include // ptrdiff_t on osx +#include +#include + +#if !defined(STBI_NO_LINEAR) || !defined(STBI_NO_HDR) +#include // ldexp +#endif + +#ifndef STBI_NO_STDIO +#include +#endif + +#ifndef STBI_ASSERT +#include +#define STBI_ASSERT(x) assert(x) +#endif + + +#ifndef _MSC_VER +#ifdef __cplusplus +#define stbi_inline inline +#else +#define stbi_inline +#endif +#else +#define stbi_inline __forceinline +#endif + + +#ifdef _MSC_VER +typedef unsigned short stbi__uint16; +typedef signed short stbi__int16; +typedef unsigned int stbi__uint32; +typedef signed int stbi__int32; +#else +#include +typedef uint16_t stbi__uint16; +typedef int16_t stbi__int16; +typedef uint32_t stbi__uint32; +typedef int32_t stbi__int32; +#endif + +// should produce compiler error if size is wrong +typedef unsigned char validate_uint32[sizeof(stbi__uint32) == 4 ? 1 : -1]; + +#ifdef _MSC_VER +#define STBI_NOTUSED(v) (void)(v) +#else +#define STBI_NOTUSED(v) (void)sizeof(v) +#endif + +#ifdef _MSC_VER +#define STBI_HAS_LROTL +#endif + +#ifdef STBI_HAS_LROTL +#define stbi_lrot(x,y) _lrotl(x,y) +#else +#define stbi_lrot(x,y) (((x) << (y)) | ((x) >> (32 - (y)))) +#endif + +#if defined(STBI_MALLOC) && defined(STBI_FREE) && (defined(STBI_REALLOC) || defined(STBI_REALLOC_SIZED)) +// ok +#elif !defined(STBI_MALLOC) && !defined(STBI_FREE) && !defined(STBI_REALLOC) && !defined(STBI_REALLOC_SIZED) +// ok +#else +#error "Must define all or none of STBI_MALLOC, STBI_FREE, and STBI_REALLOC (or STBI_REALLOC_SIZED)." +#endif + +#ifndef STBI_MALLOC +#define STBI_MALLOC(sz) malloc(sz) +#define STBI_REALLOC(p,newsz) realloc(p,newsz) +#define STBI_FREE(p) free(p) +#endif + +#ifndef STBI_REALLOC_SIZED +#define STBI_REALLOC_SIZED(p,oldsz,newsz) STBI_REALLOC(p,newsz) +#endif + +// x86/x64 detection +#if defined(__x86_64__) || defined(_M_X64) +#define STBI__X64_TARGET +#elif defined(__i386) || defined(_M_IX86) +#define STBI__X86_TARGET +#endif + +#if defined(__GNUC__) && (defined(STBI__X86_TARGET) || defined(STBI__X64_TARGET)) && !defined(__SSE2__) && !defined(STBI_NO_SIMD) +// NOTE: not clear do we actually need this for the 64-bit path? +// gcc doesn't support sse2 intrinsics unless you compile with -msse2, +// (but compiling with -msse2 allows the compiler to use SSE2 everywhere; +// this is just broken and gcc are jerks for not fixing it properly +// http://www.virtualdub.org/blog/pivot/entry.php?id=363 ) +#define STBI_NO_SIMD +#endif + +#if defined(__MINGW32__) && defined(STBI__X86_TARGET) && !defined(STBI_MINGW_ENABLE_SSE2) && !defined(STBI_NO_SIMD) +// Note that __MINGW32__ doesn't actually mean 32-bit, so we have to avoid STBI__X64_TARGET +// +// 32-bit MinGW wants ESP to be 16-byte aligned, but this is not in the +// Windows ABI and VC++ as well as Windows DLLs don't maintain that invariant. +// As a result, enabling SSE2 on 32-bit MinGW is dangerous when not +// simultaneously enabling "-mstackrealign". +// +// See https://github.com/nothings/stb/issues/81 for more information. +// +// So default to no SSE2 on 32-bit MinGW. If you've read this far and added +// -mstackrealign to your build settings, feel free to #define STBI_MINGW_ENABLE_SSE2. +#define STBI_NO_SIMD +#endif + +#if !defined(STBI_NO_SIMD) && defined(STBI__X86_TARGET) +#define STBI_SSE2 +#include + +#ifdef _MSC_VER + +#if _MSC_VER >= 1400 // not VC6 +#include // __cpuid +static int stbi__cpuid3(void) +{ + int info[4]; + __cpuid(info, 1); + return info[3]; +} +#else +static int stbi__cpuid3(void) +{ + int res; + __asm { + mov eax, 1 + cpuid + mov res, edx + } + return res; +} +#endif + +#define STBI_SIMD_ALIGN(type, name) __declspec(align(16)) type name + +static int stbi__sse2_available() +{ + int info3 = stbi__cpuid3(); + return ((info3 >> 26) & 1) != 0; +} +#else // assume GCC-style if not VC++ +#define STBI_SIMD_ALIGN(type, name) type name __attribute__((aligned(16))) + +static int stbi__sse2_available() +{ +#if defined(__GNUC__) && (__GNUC__ * 100 + __GNUC_MINOR__) >= 408 // GCC 4.8 or later + // GCC 4.8+ has a nice way to do this + return __builtin_cpu_supports("sse2"); +#else + // portable way to do this, preferably without using GCC inline ASM? + // just bail for now. + return 0; +#endif +} +#endif +#endif + +// ARM NEON +#if defined(STBI_NO_SIMD) && defined(STBI_NEON) +#undef STBI_NEON +#endif + +#ifdef STBI_NEON +#include +// assume GCC or Clang on ARM targets +#define STBI_SIMD_ALIGN(type, name) type name __attribute__((aligned(16))) +#endif + +#ifndef STBI_SIMD_ALIGN +#define STBI_SIMD_ALIGN(type, name) type name +#endif + +/////////////////////////////////////////////// +// +// stbi__context struct and start_xxx functions + +// stbi__context structure is our basic context used by all images, so it +// contains all the IO context, plus some basic image information +typedef struct +{ + stbi__uint32 img_x, img_y; + int img_n, img_out_n; + + stbi_io_callbacks io; + void *io_user_data; + + int read_from_callbacks; + int buflen; + stbi_uc buffer_start[128]; + + stbi_uc *img_buffer, *img_buffer_end; + stbi_uc *img_buffer_original, *img_buffer_original_end; +} stbi__context; + + +static void stbi__refill_buffer(stbi__context *s); + +// initialize a memory-decode context +static void stbi__start_mem(stbi__context *s, stbi_uc const *buffer, int len) +{ + s->io.read = NULL; + s->read_from_callbacks = 0; + s->img_buffer = s->img_buffer_original = (stbi_uc *)buffer; + s->img_buffer_end = s->img_buffer_original_end = (stbi_uc *)buffer + len; +} + +// initialize a callback-based context +static void stbi__start_callbacks(stbi__context *s, stbi_io_callbacks *c, void *user) +{ + s->io = *c; + s->io_user_data = user; + s->buflen = sizeof(s->buffer_start); + s->read_from_callbacks = 1; + s->img_buffer_original = s->buffer_start; + stbi__refill_buffer(s); + s->img_buffer_original_end = s->img_buffer_end; +} + +#ifndef STBI_NO_STDIO + +static int stbi__stdio_read(void *user, char *data, int size) +{ + return (int)fread(data, 1, size, (FILE*)user); +} + +static void stbi__stdio_skip(void *user, int n) +{ + fseek((FILE*)user, n, SEEK_CUR); +} + +static int stbi__stdio_eof(void *user) +{ + return feof((FILE*)user); +} + +static stbi_io_callbacks stbi__stdio_callbacks = +{ + stbi__stdio_read, + stbi__stdio_skip, + stbi__stdio_eof, +}; + +static void stbi__start_file(stbi__context *s, FILE *f) +{ + stbi__start_callbacks(s, &stbi__stdio_callbacks, (void *)f); +} + +//static void stop_file(stbi__context *s) { } + +#endif // !STBI_NO_STDIO + +static void stbi__rewind(stbi__context *s) +{ + // conceptually rewind SHOULD rewind to the beginning of the stream, + // but we just rewind to the beginning of the initial buffer, because + // we only use it after doing 'test', which only ever looks at at most 92 bytes + s->img_buffer = s->img_buffer_original; + s->img_buffer_end = s->img_buffer_original_end; +} + +#ifndef STBI_NO_JPEG +static int stbi__jpeg_test(stbi__context *s); +static stbi_uc *stbi__jpeg_load(stbi__context *s, int *x, int *y, int *comp, int req_comp); +static int stbi__jpeg_info(stbi__context *s, int *x, int *y, int *comp); +#endif + +#ifndef STBI_NO_PNG +static int stbi__png_test(stbi__context *s); +static stbi_uc *stbi__png_load(stbi__context *s, int *x, int *y, int *comp, int req_comp); +static int stbi__png_info(stbi__context *s, int *x, int *y, int *comp); +#endif + +#ifndef STBI_NO_BMP +static int stbi__bmp_test(stbi__context *s); +static stbi_uc *stbi__bmp_load(stbi__context *s, int *x, int *y, int *comp, int req_comp); +static int stbi__bmp_info(stbi__context *s, int *x, int *y, int *comp); +#endif + +#ifndef STBI_NO_TGA +static int stbi__tga_test(stbi__context *s); +static stbi_uc *stbi__tga_load(stbi__context *s, int *x, int *y, int *comp, int req_comp); +static int stbi__tga_info(stbi__context *s, int *x, int *y, int *comp); +#endif + +#ifndef STBI_NO_PSD +static int stbi__psd_test(stbi__context *s); +static stbi_uc *stbi__psd_load(stbi__context *s, int *x, int *y, int *comp, int req_comp); +static int stbi__psd_info(stbi__context *s, int *x, int *y, int *comp); +#endif + +#ifndef STBI_NO_HDR +static int stbi__hdr_test(stbi__context *s); +static float *stbi__hdr_load(stbi__context *s, int *x, int *y, int *comp, int req_comp); +static int stbi__hdr_info(stbi__context *s, int *x, int *y, int *comp); +#endif + +#ifndef STBI_NO_PIC +static int stbi__pic_test(stbi__context *s); +static stbi_uc *stbi__pic_load(stbi__context *s, int *x, int *y, int *comp, int req_comp); +static int stbi__pic_info(stbi__context *s, int *x, int *y, int *comp); +#endif + +#ifndef STBI_NO_GIF +static int stbi__gif_test(stbi__context *s); +static stbi_uc *stbi__gif_load(stbi__context *s, int *x, int *y, int *comp, int req_comp); +static int stbi__gif_info(stbi__context *s, int *x, int *y, int *comp); +#endif + +#ifndef STBI_NO_PNM +static int stbi__pnm_test(stbi__context *s); +static stbi_uc *stbi__pnm_load(stbi__context *s, int *x, int *y, int *comp, int req_comp); +static int stbi__pnm_info(stbi__context *s, int *x, int *y, int *comp); +#endif + +// this is not threadsafe +static const char *stbi__g_failure_reason; + +STBIDEF const char *stbi_failure_reason(void) +{ + return stbi__g_failure_reason; +} + +static int stbi__err(const char *str) +{ + stbi__g_failure_reason = str; + return 0; +} + +static void *stbi__malloc(size_t size) +{ + return STBI_MALLOC(size); +} + +// stbi__err - error +// stbi__errpf - error returning pointer to float +// stbi__errpuc - error returning pointer to unsigned char + +#ifdef STBI_NO_FAILURE_STRINGS +#define stbi__err(x,y) 0 +#elif defined(STBI_FAILURE_USERMSG) +#define stbi__err(x,y) stbi__err(y) +#else +#define stbi__err(x,y) stbi__err(x) +#endif + +#define stbi__errpf(x,y) ((float *)(size_t) (stbi__err(x,y)?NULL:NULL)) +#define stbi__errpuc(x,y) ((unsigned char *)(size_t) (stbi__err(x,y)?NULL:NULL)) + +STBIDEF void stbi_image_free(void *retval_from_stbi_load) +{ + STBI_FREE(retval_from_stbi_load); +} + +#ifndef STBI_NO_LINEAR +static float *stbi__ldr_to_hdr(stbi_uc *data, int x, int y, int comp); +#endif + +#ifndef STBI_NO_HDR +static stbi_uc *stbi__hdr_to_ldr(float *data, int x, int y, int comp); +#endif + +static int stbi__vertically_flip_on_load = 0; + +STBIDEF void stbi_set_flip_vertically_on_load(int flag_true_if_should_flip) +{ + stbi__vertically_flip_on_load = flag_true_if_should_flip; +} + +static unsigned char *stbi__load_main(stbi__context *s, int *x, int *y, int *comp, int req_comp) +{ +#ifndef STBI_NO_JPEG + if (stbi__jpeg_test(s)) return stbi__jpeg_load(s, x, y, comp, req_comp); +#endif +#ifndef STBI_NO_PNG + if (stbi__png_test(s)) return stbi__png_load(s, x, y, comp, req_comp); +#endif +#ifndef STBI_NO_BMP + if (stbi__bmp_test(s)) return stbi__bmp_load(s, x, y, comp, req_comp); +#endif +#ifndef STBI_NO_GIF + if (stbi__gif_test(s)) return stbi__gif_load(s, x, y, comp, req_comp); +#endif +#ifndef STBI_NO_PSD + if (stbi__psd_test(s)) return stbi__psd_load(s, x, y, comp, req_comp); +#endif +#ifndef STBI_NO_PIC + if (stbi__pic_test(s)) return stbi__pic_load(s, x, y, comp, req_comp); +#endif +#ifndef STBI_NO_PNM + if (stbi__pnm_test(s)) return stbi__pnm_load(s, x, y, comp, req_comp); +#endif + +#ifndef STBI_NO_HDR + if (stbi__hdr_test(s)) { + float *hdr = stbi__hdr_load(s, x, y, comp, req_comp); + return stbi__hdr_to_ldr(hdr, *x, *y, req_comp ? req_comp : *comp); + } +#endif + +#ifndef STBI_NO_TGA + // test tga last because it's a crappy test! + if (stbi__tga_test(s)) + return stbi__tga_load(s, x, y, comp, req_comp); +#endif + + return stbi__errpuc("unknown image type", "Image not of any known type, or corrupt"); +} + +static unsigned char *stbi__load_flip(stbi__context *s, int *x, int *y, int *comp, int req_comp) +{ + unsigned char *result = stbi__load_main(s, x, y, comp, req_comp); + + if (stbi__vertically_flip_on_load && result != NULL) { + int w = *x, h = *y; + int depth = req_comp ? req_comp : *comp; + int row, col, z; + stbi_uc temp; + + // @OPTIMIZE: use a bigger temp buffer and memcpy multiple pixels at once + for (row = 0; row < (h >> 1); row++) { + for (col = 0; col < w; col++) { + for (z = 0; z < depth; z++) { + temp = result[(row * w + col) * depth + z]; + result[(row * w + col) * depth + z] = result[((h - row - 1) * w + col) * depth + z]; + result[((h - row - 1) * w + col) * depth + z] = temp; + } + } + } + } + + return result; +} + +#ifndef STBI_NO_HDR +static void stbi__float_postprocess(float *result, int *x, int *y, int *comp, int req_comp) +{ + if (stbi__vertically_flip_on_load && result != NULL) { + int w = *x, h = *y; + int depth = req_comp ? req_comp : *comp; + int row, col, z; + float temp; + + // @OPTIMIZE: use a bigger temp buffer and memcpy multiple pixels at once + for (row = 0; row < (h >> 1); row++) { + for (col = 0; col < w; col++) { + for (z = 0; z < depth; z++) { + temp = result[(row * w + col) * depth + z]; + result[(row * w + col) * depth + z] = result[((h - row - 1) * w + col) * depth + z]; + result[((h - row - 1) * w + col) * depth + z] = temp; + } + } + } + } +} +#endif + +#ifndef STBI_NO_STDIO + +static FILE *stbi__fopen(char const *filename, char const *mode) +{ + FILE *f; +#if defined(_MSC_VER) && _MSC_VER >= 1400 + if (0 != fopen_s(&f, filename, mode)) + f = 0; +#else + f = fopen(filename, mode); +#endif + return f; +} + + +STBIDEF stbi_uc *stbi_load(char const *filename, int *x, int *y, int *comp, int req_comp) +{ + FILE *f = stbi__fopen(filename, "rb"); + unsigned char *result; + if (!f) return stbi__errpuc("can't fopen", "Unable to open file"); + result = stbi_load_from_file(f, x, y, comp, req_comp); + fclose(f); + return result; +} + +STBIDEF stbi_uc *stbi_load_from_file(FILE *f, int *x, int *y, int *comp, int req_comp) +{ + unsigned char *result; + stbi__context s; + stbi__start_file(&s, f); + result = stbi__load_flip(&s, x, y, comp, req_comp); + if (result) { + // need to 'unget' all the characters in the IO buffer + fseek(f, -(int)(s.img_buffer_end - s.img_buffer), SEEK_CUR); + } + return result; +} +#endif //!STBI_NO_STDIO + +STBIDEF stbi_uc *stbi_load_from_memory(stbi_uc const *buffer, int len, int *x, int *y, int *comp, int req_comp) +{ + stbi__context s; + stbi__start_mem(&s, buffer, len); + return stbi__load_flip(&s, x, y, comp, req_comp); +} + +STBIDEF stbi_uc *stbi_load_from_callbacks(stbi_io_callbacks const *clbk, void *user, int *x, int *y, int *comp, int req_comp) +{ + stbi__context s; + stbi__start_callbacks(&s, (stbi_io_callbacks *)clbk, user); + return stbi__load_flip(&s, x, y, comp, req_comp); +} + +#ifndef STBI_NO_LINEAR +static float *stbi__loadf_main(stbi__context *s, int *x, int *y, int *comp, int req_comp) +{ + unsigned char *data; +#ifndef STBI_NO_HDR + if (stbi__hdr_test(s)) { + float *hdr_data = stbi__hdr_load(s, x, y, comp, req_comp); + if (hdr_data) + stbi__float_postprocess(hdr_data, x, y, comp, req_comp); + return hdr_data; + } +#endif + data = stbi__load_flip(s, x, y, comp, req_comp); + if (data) + return stbi__ldr_to_hdr(data, *x, *y, req_comp ? req_comp : *comp); + return stbi__errpf("unknown image type", "Image not of any known type, or corrupt"); +} + +STBIDEF float *stbi_loadf_from_memory(stbi_uc const *buffer, int len, int *x, int *y, int *comp, int req_comp) +{ + stbi__context s; + stbi__start_mem(&s, buffer, len); + return stbi__loadf_main(&s, x, y, comp, req_comp); +} + +STBIDEF float *stbi_loadf_from_callbacks(stbi_io_callbacks const *clbk, void *user, int *x, int *y, int *comp, int req_comp) +{ + stbi__context s; + stbi__start_callbacks(&s, (stbi_io_callbacks *)clbk, user); + return stbi__loadf_main(&s, x, y, comp, req_comp); +} + +#ifndef STBI_NO_STDIO +STBIDEF float *stbi_loadf(char const *filename, int *x, int *y, int *comp, int req_comp) +{ + float *result; + FILE *f = stbi__fopen(filename, "rb"); + if (!f) return stbi__errpf("can't fopen", "Unable to open file"); + result = stbi_loadf_from_file(f, x, y, comp, req_comp); + fclose(f); + return result; +} + +STBIDEF float *stbi_loadf_from_file(FILE *f, int *x, int *y, int *comp, int req_comp) +{ + stbi__context s; + stbi__start_file(&s, f); + return stbi__loadf_main(&s, x, y, comp, req_comp); +} +#endif // !STBI_NO_STDIO + +#endif // !STBI_NO_LINEAR + +// these is-hdr-or-not is defined independent of whether STBI_NO_LINEAR is +// defined, for API simplicity; if STBI_NO_LINEAR is defined, it always +// reports false! + +STBIDEF int stbi_is_hdr_from_memory(stbi_uc const *buffer, int len) +{ +#ifndef STBI_NO_HDR + stbi__context s; + stbi__start_mem(&s, buffer, len); + return stbi__hdr_test(&s); +#else + STBI_NOTUSED(buffer); + STBI_NOTUSED(len); + return 0; +#endif +} + +#ifndef STBI_NO_STDIO +STBIDEF int stbi_is_hdr(char const *filename) +{ + FILE *f = stbi__fopen(filename, "rb"); + int result = 0; + if (f) { + result = stbi_is_hdr_from_file(f); + fclose(f); + } + return result; +} + +STBIDEF int stbi_is_hdr_from_file(FILE *f) +{ +#ifndef STBI_NO_HDR + stbi__context s; + stbi__start_file(&s, f); + return stbi__hdr_test(&s); +#else + STBI_NOTUSED(f); + return 0; +#endif +} +#endif // !STBI_NO_STDIO + +STBIDEF int stbi_is_hdr_from_callbacks(stbi_io_callbacks const *clbk, void *user) +{ +#ifndef STBI_NO_HDR + stbi__context s; + stbi__start_callbacks(&s, (stbi_io_callbacks *)clbk, user); + return stbi__hdr_test(&s); +#else + STBI_NOTUSED(clbk); + STBI_NOTUSED(user); + return 0; +#endif +} + +#ifndef STBI_NO_LINEAR +static float stbi__l2h_gamma = 2.2f, stbi__l2h_scale = 1.0f; + +STBIDEF void stbi_ldr_to_hdr_gamma(float gamma) { stbi__l2h_gamma = gamma; } +STBIDEF void stbi_ldr_to_hdr_scale(float scale) { stbi__l2h_scale = scale; } +#endif + +static float stbi__h2l_gamma_i = 1.0f / 2.2f, stbi__h2l_scale_i = 1.0f; + +STBIDEF void stbi_hdr_to_ldr_gamma(float gamma) { stbi__h2l_gamma_i = 1 / gamma; } +STBIDEF void stbi_hdr_to_ldr_scale(float scale) { stbi__h2l_scale_i = 1 / scale; } + + +////////////////////////////////////////////////////////////////////////////// +// +// Common code used by all image loaders +// + +enum +{ + STBI__SCAN_load = 0, + STBI__SCAN_type, + STBI__SCAN_header +}; + +static void stbi__refill_buffer(stbi__context *s) +{ + int n = (s->io.read)(s->io_user_data, (char*)s->buffer_start, s->buflen); + if (n == 0) { + // at end of file, treat same as if from memory, but need to handle case + // where s->img_buffer isn't pointing to safe memory, e.g. 0-byte file + s->read_from_callbacks = 0; + s->img_buffer = s->buffer_start; + s->img_buffer_end = s->buffer_start + 1; + *s->img_buffer = 0; + } + else { + s->img_buffer = s->buffer_start; + s->img_buffer_end = s->buffer_start + n; + } +} + +stbi_inline static stbi_uc stbi__get8(stbi__context *s) +{ + if (s->img_buffer < s->img_buffer_end) + return *s->img_buffer++; + if (s->read_from_callbacks) { + stbi__refill_buffer(s); + return *s->img_buffer++; + } + return 0; +} + +stbi_inline static int stbi__at_eof(stbi__context *s) +{ + if (s->io.read) { + if (!(s->io.eof)(s->io_user_data)) return 0; + // if feof() is true, check if buffer = end + // special case: we've only got the special 0 character at the end + if (s->read_from_callbacks == 0) return 1; + } + + return s->img_buffer >= s->img_buffer_end; +} + +static void stbi__skip(stbi__context *s, int n) +{ + if (n < 0) { + s->img_buffer = s->img_buffer_end; + return; + } + if (s->io.read) { + int blen = (int)(s->img_buffer_end - s->img_buffer); + if (blen < n) { + s->img_buffer = s->img_buffer_end; + (s->io.skip)(s->io_user_data, n - blen); + return; + } + } + s->img_buffer += n; +} + +static int stbi__getn(stbi__context *s, stbi_uc *buffer, int n) +{ + if (s->io.read) { + int blen = (int)(s->img_buffer_end - s->img_buffer); + if (blen < n) { + int res, count; + + memcpy(buffer, s->img_buffer, blen); + + count = (s->io.read)(s->io_user_data, (char*)buffer + blen, n - blen); + res = (count == (n - blen)); + s->img_buffer = s->img_buffer_end; + return res; + } + } + + if (s->img_buffer + n <= s->img_buffer_end) { + memcpy(buffer, s->img_buffer, n); + s->img_buffer += n; + return 1; + } + else + return 0; +} + +static int stbi__get16be(stbi__context *s) +{ + int z = stbi__get8(s); + return (z << 8) + stbi__get8(s); +} + +static stbi__uint32 stbi__get32be(stbi__context *s) +{ + stbi__uint32 z = stbi__get16be(s); + return (z << 16) + stbi__get16be(s); +} + +#if defined(STBI_NO_BMP) && defined(STBI_NO_TGA) && defined(STBI_NO_GIF) +// nothing +#else +static int stbi__get16le(stbi__context *s) +{ + int z = stbi__get8(s); + return z + (stbi__get8(s) << 8); +} +#endif + +#ifndef STBI_NO_BMP +static stbi__uint32 stbi__get32le(stbi__context *s) +{ + stbi__uint32 z = stbi__get16le(s); + return z + (stbi__get16le(s) << 16); +} +#endif + +#define STBI__BYTECAST(x) ((stbi_uc) ((x) & 255)) // truncate int to byte without warnings + + +////////////////////////////////////////////////////////////////////////////// +// +// generic converter from built-in img_n to req_comp +// individual types do this automatically as much as possible (e.g. jpeg +// does all cases internally since it needs to colorspace convert anyway, +// and it never has alpha, so very few cases ). png can automatically +// interleave an alpha=255 channel, but falls back to this for other cases +// +// assume data buffer is malloced, so malloc a new one and free that one +// only failure mode is malloc failing + +static stbi_uc stbi__compute_y(int r, int g, int b) +{ + return (stbi_uc)(((r * 77) + (g * 150) + (29 * b)) >> 8); +} + +static unsigned char *stbi__convert_format(unsigned char *data, int img_n, int req_comp, unsigned int x, unsigned int y) +{ + int i, j; + unsigned char *good; + + if (req_comp == img_n) return data; + STBI_ASSERT(req_comp >= 1 && req_comp <= 4); + + good = (unsigned char *)stbi__malloc(req_comp * x * y); + if (good == NULL) { + STBI_FREE(data); + return stbi__errpuc("outofmem", "Out of memory"); + } + + for (j = 0; j < (int)y; ++j) { + unsigned char *src = data + j * x * img_n; + unsigned char *dest = good + j * x * req_comp; + +#define COMBO(a,b) ((a)*8+(b)) +#define CASE(a,b) case COMBO(a,b): for(i=x-1; i >= 0; --i, src += a, dest += b) + // convert source image with img_n components to one with req_comp components; + // avoid switch per pixel, so use switch per scanline and massive macros + switch (COMBO(img_n, req_comp)) { + CASE(1, 2) dest[0] = src[0], dest[1] = 255; break; + CASE(1, 3) dest[0] = dest[1] = dest[2] = src[0]; break; + CASE(1, 4) dest[0] = dest[1] = dest[2] = src[0], dest[3] = 255; break; + CASE(2, 1) dest[0] = src[0]; break; + CASE(2, 3) dest[0] = dest[1] = dest[2] = src[0]; break; + CASE(2, 4) dest[0] = dest[1] = dest[2] = src[0], dest[3] = src[1]; break; + CASE(3, 4) dest[0] = src[0], dest[1] = src[1], dest[2] = src[2], dest[3] = 255; break; + CASE(3, 1) dest[0] = stbi__compute_y(src[0], src[1], src[2]); break; + CASE(3, 2) dest[0] = stbi__compute_y(src[0], src[1], src[2]), dest[1] = 255; break; + CASE(4, 1) dest[0] = stbi__compute_y(src[0], src[1], src[2]); break; + CASE(4, 2) dest[0] = stbi__compute_y(src[0], src[1], src[2]), dest[1] = src[3]; break; + CASE(4, 3) dest[0] = src[0], dest[1] = src[1], dest[2] = src[2]; break; + default: STBI_ASSERT(0); + } +#undef CASE + } + + STBI_FREE(data); + return good; +} + +#ifndef STBI_NO_LINEAR +static float *stbi__ldr_to_hdr(stbi_uc *data, int x, int y, int comp) +{ + int i, k, n; + float *output = (float *)stbi__malloc(x * y * comp * sizeof(float)); + if (output == NULL) { STBI_FREE(data); return stbi__errpf("outofmem", "Out of memory"); } + // compute number of non-alpha components + if (comp & 1) n = comp; else n = comp - 1; + for (i = 0; i < x*y; ++i) { + for (k = 0; k < n; ++k) { + output[i*comp + k] = (float)(pow(data[i*comp + k] / 255.0f, stbi__l2h_gamma) * stbi__l2h_scale); + } + if (k < comp) output[i*comp + k] = data[i*comp + k] / 255.0f; + } + STBI_FREE(data); + return output; +} +#endif + +#ifndef STBI_NO_HDR +#define stbi__float2int(x) ((int) (x)) +static stbi_uc *stbi__hdr_to_ldr(float *data, int x, int y, int comp) +{ + int i, k, n; + stbi_uc *output = (stbi_uc *)stbi__malloc(x * y * comp); + if (output == NULL) { STBI_FREE(data); return stbi__errpuc("outofmem", "Out of memory"); } + // compute number of non-alpha components + if (comp & 1) n = comp; else n = comp - 1; + for (i = 0; i < x*y; ++i) { + for (k = 0; k < n; ++k) { + float z = (float)pow(data[i*comp + k] * stbi__h2l_scale_i, stbi__h2l_gamma_i) * 255 + 0.5f; + if (z < 0) z = 0; + if (z > 255) z = 255; + output[i*comp + k] = (stbi_uc)stbi__float2int(z); + } + if (k < comp) { + float z = data[i*comp + k] * 255 + 0.5f; + if (z < 0) z = 0; + if (z > 255) z = 255; + output[i*comp + k] = (stbi_uc)stbi__float2int(z); + } + } + STBI_FREE(data); + return output; +} +#endif + +////////////////////////////////////////////////////////////////////////////// +// +// "baseline" JPEG/JFIF decoder +// +// simple implementation +// - doesn't support delayed output of y-dimension +// - simple interface (only one output format: 8-bit interleaved RGB) +// - doesn't try to recover corrupt jpegs +// - doesn't allow partial loading, loading multiple at once +// - still fast on x86 (copying globals into locals doesn't help x86) +// - allocates lots of intermediate memory (full size of all components) +// - non-interleaved case requires this anyway +// - allows good upsampling (see next) +// high-quality +// - upsampled channels are bilinearly interpolated, even across blocks +// - quality integer IDCT derived from IJG's 'slow' +// performance +// - fast huffman; reasonable integer IDCT +// - some SIMD kernels for common paths on targets with SSE2/NEON +// - uses a lot of intermediate memory, could cache poorly + +#ifndef STBI_NO_JPEG + +// huffman decoding acceleration +#define FAST_BITS 9 // larger handles more cases; smaller stomps less cache + +typedef struct +{ + stbi_uc fast[1 << FAST_BITS]; + // weirdly, repacking this into AoS is a 10% speed loss, instead of a win + stbi__uint16 code[256]; + stbi_uc values[256]; + stbi_uc size[257]; + unsigned int maxcode[18]; + int delta[17]; // old 'firstsymbol' - old 'firstcode' +} stbi__huffman; + +typedef struct +{ + stbi__context *s; + stbi__huffman huff_dc[4]; + stbi__huffman huff_ac[4]; + stbi_uc dequant[4][64]; + stbi__int16 fast_ac[4][1 << FAST_BITS]; + + // sizes for components, interleaved MCUs + int img_h_max, img_v_max; + int img_mcu_x, img_mcu_y; + int img_mcu_w, img_mcu_h; + + // definition of jpeg image component + struct + { + int id; + int h, v; + int tq; + int hd, ha; + int dc_pred; + + int x, y, w2, h2; + stbi_uc *data; + void *raw_data, *raw_coeff; + stbi_uc *linebuf; + short *coeff; // progressive only + int coeff_w, coeff_h; // number of 8x8 coefficient blocks + } img_comp[4]; + + stbi__uint32 code_buffer; // jpeg entropy-coded buffer + int code_bits; // number of valid bits + unsigned char marker; // marker seen while filling entropy buffer + int nomore; // flag if we saw a marker so must stop + + int progressive; + int spec_start; + int spec_end; + int succ_high; + int succ_low; + int eob_run; + + int scan_n, order[4]; + int restart_interval, todo; + + // kernels + void(*idct_block_kernel)(stbi_uc *out, int out_stride, short data[64]); + void(*YCbCr_to_RGB_kernel)(stbi_uc *out, const stbi_uc *y, const stbi_uc *pcb, const stbi_uc *pcr, int count, int step); + stbi_uc *(*resample_row_hv_2_kernel)(stbi_uc *out, stbi_uc *in_near, stbi_uc *in_far, int w, int hs); +} stbi__jpeg; + +static int stbi__build_huffman(stbi__huffman *h, int *count) +{ + int i, j, k = 0, code; + // build size list for each symbol (from JPEG spec) + for (i = 0; i < 16; ++i) + for (j = 0; j < count[i]; ++j) + h->size[k++] = (stbi_uc)(i + 1); + h->size[k] = 0; + + // compute actual symbols (from jpeg spec) + code = 0; + k = 0; + for (j = 1; j <= 16; ++j) { + // compute delta to add to code to compute symbol id + h->delta[j] = k - code; + if (h->size[k] == j) { + while (h->size[k] == j) + h->code[k++] = (stbi__uint16)(code++); + if (code - 1 >= (1 << j)) return stbi__err("bad code lengths", "Corrupt JPEG"); + } + // compute largest code + 1 for this size, preshifted as needed later + h->maxcode[j] = code << (16 - j); + code <<= 1; + } + h->maxcode[j] = 0xffffffff; + + // build non-spec acceleration table; 255 is flag for not-accelerated + memset(h->fast, 255, 1 << FAST_BITS); + for (i = 0; i < k; ++i) { + int s = h->size[i]; + if (s <= FAST_BITS) { + int c = h->code[i] << (FAST_BITS - s); + int m = 1 << (FAST_BITS - s); + for (j = 0; j < m; ++j) { + h->fast[c + j] = (stbi_uc)i; + } + } + } + return 1; +} + +// build a table that decodes both magnitude and value of small ACs in +// one go. +static void stbi__build_fast_ac(stbi__int16 *fast_ac, stbi__huffman *h) +{ + int i; + for (i = 0; i < (1 << FAST_BITS); ++i) { + stbi_uc fast = h->fast[i]; + fast_ac[i] = 0; + if (fast < 255) { + int rs = h->values[fast]; + int run = (rs >> 4) & 15; + int magbits = rs & 15; + int len = h->size[fast]; + + if (magbits && len + magbits <= FAST_BITS) { + // magnitude code followed by receive_extend code + int k = ((i << len) & ((1 << FAST_BITS) - 1)) >> (FAST_BITS - magbits); + int m = 1 << (magbits - 1); + if (k < m) k += (-1 << magbits) + 1; + // if the result is small enough, we can fit it in fast_ac table + if (k >= -128 && k <= 127) + fast_ac[i] = (stbi__int16)((k << 8) + (run << 4) + (len + magbits)); + } + } + } +} + +static void stbi__grow_buffer_unsafe(stbi__jpeg *j) +{ + do { + int b = j->nomore ? 0 : stbi__get8(j->s); + if (b == 0xff) { + int c = stbi__get8(j->s); + if (c != 0) { + j->marker = (unsigned char)c; + j->nomore = 1; + return; + } + } + j->code_buffer |= b << (24 - j->code_bits); + j->code_bits += 8; + } while (j->code_bits <= 24); +} + +// (1 << n) - 1 +static stbi__uint32 stbi__bmask[17] = { 0,1,3,7,15,31,63,127,255,511,1023,2047,4095,8191,16383,32767,65535 }; + +// decode a jpeg huffman value from the bitstream +stbi_inline static int stbi__jpeg_huff_decode(stbi__jpeg *j, stbi__huffman *h) +{ + unsigned int temp; + int c, k; + + if (j->code_bits < 16) stbi__grow_buffer_unsafe(j); + + // look at the top FAST_BITS and determine what symbol ID it is, + // if the code is <= FAST_BITS + c = (j->code_buffer >> (32 - FAST_BITS)) & ((1 << FAST_BITS) - 1); + k = h->fast[c]; + if (k < 255) { + int s = h->size[k]; + if (s > j->code_bits) + return -1; + j->code_buffer <<= s; + j->code_bits -= s; + return h->values[k]; + } + + // naive test is to shift the code_buffer down so k bits are + // valid, then test against maxcode. To speed this up, we've + // preshifted maxcode left so that it has (16-k) 0s at the + // end; in other words, regardless of the number of bits, it + // wants to be compared against something shifted to have 16; + // that way we don't need to shift inside the loop. + temp = j->code_buffer >> 16; + for (k = FAST_BITS + 1; ; ++k) + if (temp < h->maxcode[k]) + break; + if (k == 17) { + // error! code not found + j->code_bits -= 16; + return -1; + } + + if (k > j->code_bits) + return -1; + + // convert the huffman code to the symbol id + c = ((j->code_buffer >> (32 - k)) & stbi__bmask[k]) + h->delta[k]; + STBI_ASSERT((((j->code_buffer) >> (32 - h->size[c])) & stbi__bmask[h->size[c]]) == h->code[c]); + + // convert the id to a symbol + j->code_bits -= k; + j->code_buffer <<= k; + return h->values[c]; +} + +// bias[n] = (-1<code_bits < n) stbi__grow_buffer_unsafe(j); + + sgn = (stbi__int32)j->code_buffer >> 31; // sign bit is always in MSB + k = stbi_lrot(j->code_buffer, n); + STBI_ASSERT(n >= 0 && n < (int)(sizeof(stbi__bmask) / sizeof(*stbi__bmask))); + j->code_buffer = k & ~stbi__bmask[n]; + k &= stbi__bmask[n]; + j->code_bits -= n; + return k + (stbi__jbias[n] & ~sgn); +} + +// get some unsigned bits +stbi_inline static int stbi__jpeg_get_bits(stbi__jpeg *j, int n) +{ + unsigned int k; + if (j->code_bits < n) stbi__grow_buffer_unsafe(j); + k = stbi_lrot(j->code_buffer, n); + j->code_buffer = k & ~stbi__bmask[n]; + k &= stbi__bmask[n]; + j->code_bits -= n; + return k; +} + +stbi_inline static int stbi__jpeg_get_bit(stbi__jpeg *j) +{ + unsigned int k; + if (j->code_bits < 1) stbi__grow_buffer_unsafe(j); + k = j->code_buffer; + j->code_buffer <<= 1; + --j->code_bits; + return k & 0x80000000; +} + +// given a value that's at position X in the zigzag stream, +// where does it appear in the 8x8 matrix coded as row-major? +static stbi_uc stbi__jpeg_dezigzag[64 + 15] = +{ + 0, 1, 8, 16, 9, 2, 3, 10, + 17, 24, 32, 25, 18, 11, 4, 5, + 12, 19, 26, 33, 40, 48, 41, 34, + 27, 20, 13, 6, 7, 14, 21, 28, + 35, 42, 49, 56, 57, 50, 43, 36, + 29, 22, 15, 23, 30, 37, 44, 51, + 58, 59, 52, 45, 38, 31, 39, 46, + 53, 60, 61, 54, 47, 55, 62, 63, + // let corrupt input sample past end + 63, 63, 63, 63, 63, 63, 63, 63, + 63, 63, 63, 63, 63, 63, 63 +}; + +// decode one 64-entry block-- +static int stbi__jpeg_decode_block(stbi__jpeg *j, short data[64], stbi__huffman *hdc, stbi__huffman *hac, stbi__int16 *fac, int b, stbi_uc *dequant) +{ + int diff, dc, k; + int t; + + if (j->code_bits < 16) stbi__grow_buffer_unsafe(j); + t = stbi__jpeg_huff_decode(j, hdc); + if (t < 0) return stbi__err("bad huffman code", "Corrupt JPEG"); + + // 0 all the ac values now so we can do it 32-bits at a time + memset(data, 0, 64 * sizeof(data[0])); + + diff = t ? stbi__extend_receive(j, t) : 0; + dc = j->img_comp[b].dc_pred + diff; + j->img_comp[b].dc_pred = dc; + data[0] = (short)(dc * dequant[0]); + + // decode AC components, see JPEG spec + k = 1; + do { + unsigned int zig; + int c, r, s; + if (j->code_bits < 16) stbi__grow_buffer_unsafe(j); + c = (j->code_buffer >> (32 - FAST_BITS)) & ((1 << FAST_BITS) - 1); + r = fac[c]; + if (r) { // fast-AC path + k += (r >> 4) & 15; // run + s = r & 15; // combined length + j->code_buffer <<= s; + j->code_bits -= s; + // decode into unzigzag'd location + zig = stbi__jpeg_dezigzag[k++]; + data[zig] = (short)((r >> 8) * dequant[zig]); + } + else { + int rs = stbi__jpeg_huff_decode(j, hac); + if (rs < 0) return stbi__err("bad huffman code", "Corrupt JPEG"); + s = rs & 15; + r = rs >> 4; + if (s == 0) { + if (rs != 0xf0) break; // end block + k += 16; + } + else { + k += r; + // decode into unzigzag'd location + zig = stbi__jpeg_dezigzag[k++]; + data[zig] = (short)(stbi__extend_receive(j, s) * dequant[zig]); + } + } + } while (k < 64); + return 1; +} + +static int stbi__jpeg_decode_block_prog_dc(stbi__jpeg *j, short data[64], stbi__huffman *hdc, int b) +{ + int diff, dc; + int t; + if (j->spec_end != 0) return stbi__err("can't merge dc and ac", "Corrupt JPEG"); + + if (j->code_bits < 16) stbi__grow_buffer_unsafe(j); + + if (j->succ_high == 0) { + // first scan for DC coefficient, must be first + memset(data, 0, 64 * sizeof(data[0])); // 0 all the ac values now + t = stbi__jpeg_huff_decode(j, hdc); + diff = t ? stbi__extend_receive(j, t) : 0; + + dc = j->img_comp[b].dc_pred + diff; + j->img_comp[b].dc_pred = dc; + data[0] = (short)(dc << j->succ_low); + } + else { + // refinement scan for DC coefficient + if (stbi__jpeg_get_bit(j)) + data[0] += (short)(1 << j->succ_low); + } + return 1; +} + +// @OPTIMIZE: store non-zigzagged during the decode passes, +// and only de-zigzag when dequantizing +static int stbi__jpeg_decode_block_prog_ac(stbi__jpeg *j, short data[64], stbi__huffman *hac, stbi__int16 *fac) +{ + int k; + if (j->spec_start == 0) return stbi__err("can't merge dc and ac", "Corrupt JPEG"); + + if (j->succ_high == 0) { + int shift = j->succ_low; + + if (j->eob_run) { + --j->eob_run; + return 1; + } + + k = j->spec_start; + do { + unsigned int zig; + int c, r, s; + if (j->code_bits < 16) stbi__grow_buffer_unsafe(j); + c = (j->code_buffer >> (32 - FAST_BITS)) & ((1 << FAST_BITS) - 1); + r = fac[c]; + if (r) { // fast-AC path + k += (r >> 4) & 15; // run + s = r & 15; // combined length + j->code_buffer <<= s; + j->code_bits -= s; + zig = stbi__jpeg_dezigzag[k++]; + data[zig] = (short)((r >> 8) << shift); + } + else { + int rs = stbi__jpeg_huff_decode(j, hac); + if (rs < 0) return stbi__err("bad huffman code", "Corrupt JPEG"); + s = rs & 15; + r = rs >> 4; + if (s == 0) { + if (r < 15) { + j->eob_run = (1 << r); + if (r) + j->eob_run += stbi__jpeg_get_bits(j, r); + --j->eob_run; + break; + } + k += 16; + } + else { + k += r; + zig = stbi__jpeg_dezigzag[k++]; + data[zig] = (short)(stbi__extend_receive(j, s) << shift); + } + } + } while (k <= j->spec_end); + } + else { + // refinement scan for these AC coefficients + + short bit = (short)(1 << j->succ_low); + + if (j->eob_run) { + --j->eob_run; + for (k = j->spec_start; k <= j->spec_end; ++k) { + short *p = &data[stbi__jpeg_dezigzag[k]]; + if (*p != 0) + if (stbi__jpeg_get_bit(j)) + if ((*p & bit) == 0) { + if (*p > 0) + *p += bit; + else + *p -= bit; + } + } + } + else { + k = j->spec_start; + do { + int r, s; + int rs = stbi__jpeg_huff_decode(j, hac); // @OPTIMIZE see if we can use the fast path here, advance-by-r is so slow, eh + if (rs < 0) return stbi__err("bad huffman code", "Corrupt JPEG"); + s = rs & 15; + r = rs >> 4; + if (s == 0) { + if (r < 15) { + j->eob_run = (1 << r) - 1; + if (r) + j->eob_run += stbi__jpeg_get_bits(j, r); + r = 64; // force end of block + } + else { + // r=15 s=0 should write 16 0s, so we just do + // a run of 15 0s and then write s (which is 0), + // so we don't have to do anything special here + } + } + else { + if (s != 1) return stbi__err("bad huffman code", "Corrupt JPEG"); + // sign bit + if (stbi__jpeg_get_bit(j)) + s = bit; + else + s = -bit; + } + + // advance by r + while (k <= j->spec_end) { + short *p = &data[stbi__jpeg_dezigzag[k++]]; + if (*p != 0) { + if (stbi__jpeg_get_bit(j)) + if ((*p & bit) == 0) { + if (*p > 0) + *p += bit; + else + *p -= bit; + } + } + else { + if (r == 0) { + *p = (short)s; + break; + } + --r; + } + } + } while (k <= j->spec_end); + } + } + return 1; +} + +// take a -128..127 value and stbi__clamp it and convert to 0..255 +stbi_inline static stbi_uc stbi__clamp(int x) +{ + // trick to use a single test to catch both cases + if ((unsigned int)x > 255) { + if (x < 0) return 0; + if (x > 255) return 255; + } + return (stbi_uc)x; +} + +#define stbi__f2f(x) ((int) (((x) * 4096 + 0.5))) +#define stbi__fsh(x) ((x) << 12) + +// derived from jidctint -- DCT_ISLOW +#define STBI__IDCT_1D(s0,s1,s2,s3,s4,s5,s6,s7) \ + int t0,t1,t2,t3,p1,p2,p3,p4,p5,x0,x1,x2,x3; \ + p2 = s2; \ + p3 = s6; \ + p1 = (p2+p3) * stbi__f2f(0.5411961f); \ + t2 = p1 + p3*stbi__f2f(-1.847759065f); \ + t3 = p1 + p2*stbi__f2f( 0.765366865f); \ + p2 = s0; \ + p3 = s4; \ + t0 = stbi__fsh(p2+p3); \ + t1 = stbi__fsh(p2-p3); \ + x0 = t0+t3; \ + x3 = t0-t3; \ + x1 = t1+t2; \ + x2 = t1-t2; \ + t0 = s7; \ + t1 = s5; \ + t2 = s3; \ + t3 = s1; \ + p3 = t0+t2; \ + p4 = t1+t3; \ + p1 = t0+t3; \ + p2 = t1+t2; \ + p5 = (p3+p4)*stbi__f2f( 1.175875602f); \ + t0 = t0*stbi__f2f( 0.298631336f); \ + t1 = t1*stbi__f2f( 2.053119869f); \ + t2 = t2*stbi__f2f( 3.072711026f); \ + t3 = t3*stbi__f2f( 1.501321110f); \ + p1 = p5 + p1*stbi__f2f(-0.899976223f); \ + p2 = p5 + p2*stbi__f2f(-2.562915447f); \ + p3 = p3*stbi__f2f(-1.961570560f); \ + p4 = p4*stbi__f2f(-0.390180644f); \ + t3 += p1+p4; \ + t2 += p2+p3; \ + t1 += p2+p4; \ + t0 += p1+p3; + +static void stbi__idct_block(stbi_uc *out, int out_stride, short data[64]) +{ + int i, val[64], *v = val; + stbi_uc *o; + short *d = data; + + // columns + for (i = 0; i < 8; ++i, ++d, ++v) { + // if all zeroes, shortcut -- this avoids dequantizing 0s and IDCTing + if (d[8] == 0 && d[16] == 0 && d[24] == 0 && d[32] == 0 + && d[40] == 0 && d[48] == 0 && d[56] == 0) { + // no shortcut 0 seconds + // (1|2|3|4|5|6|7)==0 0 seconds + // all separate -0.047 seconds + // 1 && 2|3 && 4|5 && 6|7: -0.047 seconds + int dcterm = d[0] << 2; + v[0] = v[8] = v[16] = v[24] = v[32] = v[40] = v[48] = v[56] = dcterm; + } + else { + STBI__IDCT_1D(d[0], d[8], d[16], d[24], d[32], d[40], d[48], d[56]) + // constants scaled things up by 1<<12; let's bring them back + // down, but keep 2 extra bits of precision + x0 += 512; x1 += 512; x2 += 512; x3 += 512; + v[0] = (x0 + t3) >> 10; + v[56] = (x0 - t3) >> 10; + v[8] = (x1 + t2) >> 10; + v[48] = (x1 - t2) >> 10; + v[16] = (x2 + t1) >> 10; + v[40] = (x2 - t1) >> 10; + v[24] = (x3 + t0) >> 10; + v[32] = (x3 - t0) >> 10; + } + } + + for (i = 0, v = val, o = out; i < 8; ++i, v += 8, o += out_stride) { + // no fast case since the first 1D IDCT spread components out + STBI__IDCT_1D(v[0], v[1], v[2], v[3], v[4], v[5], v[6], v[7]) + // constants scaled things up by 1<<12, plus we had 1<<2 from first + // loop, plus horizontal and vertical each scale by sqrt(8) so together + // we've got an extra 1<<3, so 1<<17 total we need to remove. + // so we want to round that, which means adding 0.5 * 1<<17, + // aka 65536. Also, we'll end up with -128 to 127 that we want + // to encode as 0..255 by adding 128, so we'll add that before the shift + x0 += 65536 + (128 << 17); + x1 += 65536 + (128 << 17); + x2 += 65536 + (128 << 17); + x3 += 65536 + (128 << 17); + // tried computing the shifts into temps, or'ing the temps to see + // if any were out of range, but that was slower + o[0] = stbi__clamp((x0 + t3) >> 17); + o[7] = stbi__clamp((x0 - t3) >> 17); + o[1] = stbi__clamp((x1 + t2) >> 17); + o[6] = stbi__clamp((x1 - t2) >> 17); + o[2] = stbi__clamp((x2 + t1) >> 17); + o[5] = stbi__clamp((x2 - t1) >> 17); + o[3] = stbi__clamp((x3 + t0) >> 17); + o[4] = stbi__clamp((x3 - t0) >> 17); + } +} + +#ifdef STBI_SSE2 +// sse2 integer IDCT. not the fastest possible implementation but it +// produces bit-identical results to the generic C version so it's +// fully "transparent". +static void stbi__idct_simd(stbi_uc *out, int out_stride, short data[64]) +{ + // This is constructed to match our regular (generic) integer IDCT exactly. + __m128i row0, row1, row2, row3, row4, row5, row6, row7; + __m128i tmp; + + // dot product constant: even elems=x, odd elems=y +#define dct_const(x,y) _mm_setr_epi16((x),(y),(x),(y),(x),(y),(x),(y)) + + // out(0) = c0[even]*x + c0[odd]*y (c0, x, y 16-bit, out 32-bit) + // out(1) = c1[even]*x + c1[odd]*y +#define dct_rot(out0,out1, x,y,c0,c1) \ + __m128i c0##lo = _mm_unpacklo_epi16((x),(y)); \ + __m128i c0##hi = _mm_unpackhi_epi16((x),(y)); \ + __m128i out0##_l = _mm_madd_epi16(c0##lo, c0); \ + __m128i out0##_h = _mm_madd_epi16(c0##hi, c0); \ + __m128i out1##_l = _mm_madd_epi16(c0##lo, c1); \ + __m128i out1##_h = _mm_madd_epi16(c0##hi, c1) + + // out = in << 12 (in 16-bit, out 32-bit) +#define dct_widen(out, in) \ + __m128i out##_l = _mm_srai_epi32(_mm_unpacklo_epi16(_mm_setzero_si128(), (in)), 4); \ + __m128i out##_h = _mm_srai_epi32(_mm_unpackhi_epi16(_mm_setzero_si128(), (in)), 4) + + // wide add +#define dct_wadd(out, a, b) \ + __m128i out##_l = _mm_add_epi32(a##_l, b##_l); \ + __m128i out##_h = _mm_add_epi32(a##_h, b##_h) + + // wide sub +#define dct_wsub(out, a, b) \ + __m128i out##_l = _mm_sub_epi32(a##_l, b##_l); \ + __m128i out##_h = _mm_sub_epi32(a##_h, b##_h) + + // butterfly a/b, add bias, then shift by "s" and pack +#define dct_bfly32o(out0, out1, a,b,bias,s) \ + { \ + __m128i abiased_l = _mm_add_epi32(a##_l, bias); \ + __m128i abiased_h = _mm_add_epi32(a##_h, bias); \ + dct_wadd(sum, abiased, b); \ + dct_wsub(dif, abiased, b); \ + out0 = _mm_packs_epi32(_mm_srai_epi32(sum_l, s), _mm_srai_epi32(sum_h, s)); \ + out1 = _mm_packs_epi32(_mm_srai_epi32(dif_l, s), _mm_srai_epi32(dif_h, s)); \ + } + + // 8-bit interleave step (for transposes) +#define dct_interleave8(a, b) \ + tmp = a; \ + a = _mm_unpacklo_epi8(a, b); \ + b = _mm_unpackhi_epi8(tmp, b) + + // 16-bit interleave step (for transposes) +#define dct_interleave16(a, b) \ + tmp = a; \ + a = _mm_unpacklo_epi16(a, b); \ + b = _mm_unpackhi_epi16(tmp, b) + +#define dct_pass(bias,shift) \ + { \ + /* even part */ \ + dct_rot(t2e,t3e, row2,row6, rot0_0,rot0_1); \ + __m128i sum04 = _mm_add_epi16(row0, row4); \ + __m128i dif04 = _mm_sub_epi16(row0, row4); \ + dct_widen(t0e, sum04); \ + dct_widen(t1e, dif04); \ + dct_wadd(x0, t0e, t3e); \ + dct_wsub(x3, t0e, t3e); \ + dct_wadd(x1, t1e, t2e); \ + dct_wsub(x2, t1e, t2e); \ + /* odd part */ \ + dct_rot(y0o,y2o, row7,row3, rot2_0,rot2_1); \ + dct_rot(y1o,y3o, row5,row1, rot3_0,rot3_1); \ + __m128i sum17 = _mm_add_epi16(row1, row7); \ + __m128i sum35 = _mm_add_epi16(row3, row5); \ + dct_rot(y4o,y5o, sum17,sum35, rot1_0,rot1_1); \ + dct_wadd(x4, y0o, y4o); \ + dct_wadd(x5, y1o, y5o); \ + dct_wadd(x6, y2o, y5o); \ + dct_wadd(x7, y3o, y4o); \ + dct_bfly32o(row0,row7, x0,x7,bias,shift); \ + dct_bfly32o(row1,row6, x1,x6,bias,shift); \ + dct_bfly32o(row2,row5, x2,x5,bias,shift); \ + dct_bfly32o(row3,row4, x3,x4,bias,shift); \ + } + + __m128i rot0_0 = dct_const(stbi__f2f(0.5411961f), stbi__f2f(0.5411961f) + stbi__f2f(-1.847759065f)); + __m128i rot0_1 = dct_const(stbi__f2f(0.5411961f) + stbi__f2f(0.765366865f), stbi__f2f(0.5411961f)); + __m128i rot1_0 = dct_const(stbi__f2f(1.175875602f) + stbi__f2f(-0.899976223f), stbi__f2f(1.175875602f)); + __m128i rot1_1 = dct_const(stbi__f2f(1.175875602f), stbi__f2f(1.175875602f) + stbi__f2f(-2.562915447f)); + __m128i rot2_0 = dct_const(stbi__f2f(-1.961570560f) + stbi__f2f(0.298631336f), stbi__f2f(-1.961570560f)); + __m128i rot2_1 = dct_const(stbi__f2f(-1.961570560f), stbi__f2f(-1.961570560f) + stbi__f2f(3.072711026f)); + __m128i rot3_0 = dct_const(stbi__f2f(-0.390180644f) + stbi__f2f(2.053119869f), stbi__f2f(-0.390180644f)); + __m128i rot3_1 = dct_const(stbi__f2f(-0.390180644f), stbi__f2f(-0.390180644f) + stbi__f2f(1.501321110f)); + + // rounding biases in column/row passes, see stbi__idct_block for explanation. + __m128i bias_0 = _mm_set1_epi32(512); + __m128i bias_1 = _mm_set1_epi32(65536 + (128 << 17)); + + // load + row0 = _mm_load_si128((const __m128i *) (data + 0 * 8)); + row1 = _mm_load_si128((const __m128i *) (data + 1 * 8)); + row2 = _mm_load_si128((const __m128i *) (data + 2 * 8)); + row3 = _mm_load_si128((const __m128i *) (data + 3 * 8)); + row4 = _mm_load_si128((const __m128i *) (data + 4 * 8)); + row5 = _mm_load_si128((const __m128i *) (data + 5 * 8)); + row6 = _mm_load_si128((const __m128i *) (data + 6 * 8)); + row7 = _mm_load_si128((const __m128i *) (data + 7 * 8)); + + // column pass + dct_pass(bias_0, 10); + + { + // 16bit 8x8 transpose pass 1 + dct_interleave16(row0, row4); + dct_interleave16(row1, row5); + dct_interleave16(row2, row6); + dct_interleave16(row3, row7); + + // transpose pass 2 + dct_interleave16(row0, row2); + dct_interleave16(row1, row3); + dct_interleave16(row4, row6); + dct_interleave16(row5, row7); + + // transpose pass 3 + dct_interleave16(row0, row1); + dct_interleave16(row2, row3); + dct_interleave16(row4, row5); + dct_interleave16(row6, row7); + } + + // row pass + dct_pass(bias_1, 17); + + { + // pack + __m128i p0 = _mm_packus_epi16(row0, row1); // a0a1a2a3...a7b0b1b2b3...b7 + __m128i p1 = _mm_packus_epi16(row2, row3); + __m128i p2 = _mm_packus_epi16(row4, row5); + __m128i p3 = _mm_packus_epi16(row6, row7); + + // 8bit 8x8 transpose pass 1 + dct_interleave8(p0, p2); // a0e0a1e1... + dct_interleave8(p1, p3); // c0g0c1g1... + + // transpose pass 2 + dct_interleave8(p0, p1); // a0c0e0g0... + dct_interleave8(p2, p3); // b0d0f0h0... + + // transpose pass 3 + dct_interleave8(p0, p2); // a0b0c0d0... + dct_interleave8(p1, p3); // a4b4c4d4... + + // store + _mm_storel_epi64((__m128i *) out, p0); out += out_stride; + _mm_storel_epi64((__m128i *) out, _mm_shuffle_epi32(p0, 0x4e)); out += out_stride; + _mm_storel_epi64((__m128i *) out, p2); out += out_stride; + _mm_storel_epi64((__m128i *) out, _mm_shuffle_epi32(p2, 0x4e)); out += out_stride; + _mm_storel_epi64((__m128i *) out, p1); out += out_stride; + _mm_storel_epi64((__m128i *) out, _mm_shuffle_epi32(p1, 0x4e)); out += out_stride; + _mm_storel_epi64((__m128i *) out, p3); out += out_stride; + _mm_storel_epi64((__m128i *) out, _mm_shuffle_epi32(p3, 0x4e)); + } + +#undef dct_const +#undef dct_rot +#undef dct_widen +#undef dct_wadd +#undef dct_wsub +#undef dct_bfly32o +#undef dct_interleave8 +#undef dct_interleave16 +#undef dct_pass +} + +#endif // STBI_SSE2 + +#ifdef STBI_NEON + +// NEON integer IDCT. should produce bit-identical +// results to the generic C version. +static void stbi__idct_simd(stbi_uc *out, int out_stride, short data[64]) +{ + int16x8_t row0, row1, row2, row3, row4, row5, row6, row7; + + int16x4_t rot0_0 = vdup_n_s16(stbi__f2f(0.5411961f)); + int16x4_t rot0_1 = vdup_n_s16(stbi__f2f(-1.847759065f)); + int16x4_t rot0_2 = vdup_n_s16(stbi__f2f(0.765366865f)); + int16x4_t rot1_0 = vdup_n_s16(stbi__f2f(1.175875602f)); + int16x4_t rot1_1 = vdup_n_s16(stbi__f2f(-0.899976223f)); + int16x4_t rot1_2 = vdup_n_s16(stbi__f2f(-2.562915447f)); + int16x4_t rot2_0 = vdup_n_s16(stbi__f2f(-1.961570560f)); + int16x4_t rot2_1 = vdup_n_s16(stbi__f2f(-0.390180644f)); + int16x4_t rot3_0 = vdup_n_s16(stbi__f2f(0.298631336f)); + int16x4_t rot3_1 = vdup_n_s16(stbi__f2f(2.053119869f)); + int16x4_t rot3_2 = vdup_n_s16(stbi__f2f(3.072711026f)); + int16x4_t rot3_3 = vdup_n_s16(stbi__f2f(1.501321110f)); + +#define dct_long_mul(out, inq, coeff) \ + int32x4_t out##_l = vmull_s16(vget_low_s16(inq), coeff); \ + int32x4_t out##_h = vmull_s16(vget_high_s16(inq), coeff) + +#define dct_long_mac(out, acc, inq, coeff) \ + int32x4_t out##_l = vmlal_s16(acc##_l, vget_low_s16(inq), coeff); \ + int32x4_t out##_h = vmlal_s16(acc##_h, vget_high_s16(inq), coeff) + +#define dct_widen(out, inq) \ + int32x4_t out##_l = vshll_n_s16(vget_low_s16(inq), 12); \ + int32x4_t out##_h = vshll_n_s16(vget_high_s16(inq), 12) + + // wide add +#define dct_wadd(out, a, b) \ + int32x4_t out##_l = vaddq_s32(a##_l, b##_l); \ + int32x4_t out##_h = vaddq_s32(a##_h, b##_h) + + // wide sub +#define dct_wsub(out, a, b) \ + int32x4_t out##_l = vsubq_s32(a##_l, b##_l); \ + int32x4_t out##_h = vsubq_s32(a##_h, b##_h) + + // butterfly a/b, then shift using "shiftop" by "s" and pack +#define dct_bfly32o(out0,out1, a,b,shiftop,s) \ + { \ + dct_wadd(sum, a, b); \ + dct_wsub(dif, a, b); \ + out0 = vcombine_s16(shiftop(sum_l, s), shiftop(sum_h, s)); \ + out1 = vcombine_s16(shiftop(dif_l, s), shiftop(dif_h, s)); \ + } + +#define dct_pass(shiftop, shift) \ + { \ + /* even part */ \ + int16x8_t sum26 = vaddq_s16(row2, row6); \ + dct_long_mul(p1e, sum26, rot0_0); \ + dct_long_mac(t2e, p1e, row6, rot0_1); \ + dct_long_mac(t3e, p1e, row2, rot0_2); \ + int16x8_t sum04 = vaddq_s16(row0, row4); \ + int16x8_t dif04 = vsubq_s16(row0, row4); \ + dct_widen(t0e, sum04); \ + dct_widen(t1e, dif04); \ + dct_wadd(x0, t0e, t3e); \ + dct_wsub(x3, t0e, t3e); \ + dct_wadd(x1, t1e, t2e); \ + dct_wsub(x2, t1e, t2e); \ + /* odd part */ \ + int16x8_t sum15 = vaddq_s16(row1, row5); \ + int16x8_t sum17 = vaddq_s16(row1, row7); \ + int16x8_t sum35 = vaddq_s16(row3, row5); \ + int16x8_t sum37 = vaddq_s16(row3, row7); \ + int16x8_t sumodd = vaddq_s16(sum17, sum35); \ + dct_long_mul(p5o, sumodd, rot1_0); \ + dct_long_mac(p1o, p5o, sum17, rot1_1); \ + dct_long_mac(p2o, p5o, sum35, rot1_2); \ + dct_long_mul(p3o, sum37, rot2_0); \ + dct_long_mul(p4o, sum15, rot2_1); \ + dct_wadd(sump13o, p1o, p3o); \ + dct_wadd(sump24o, p2o, p4o); \ + dct_wadd(sump23o, p2o, p3o); \ + dct_wadd(sump14o, p1o, p4o); \ + dct_long_mac(x4, sump13o, row7, rot3_0); \ + dct_long_mac(x5, sump24o, row5, rot3_1); \ + dct_long_mac(x6, sump23o, row3, rot3_2); \ + dct_long_mac(x7, sump14o, row1, rot3_3); \ + dct_bfly32o(row0,row7, x0,x7,shiftop,shift); \ + dct_bfly32o(row1,row6, x1,x6,shiftop,shift); \ + dct_bfly32o(row2,row5, x2,x5,shiftop,shift); \ + dct_bfly32o(row3,row4, x3,x4,shiftop,shift); \ + } + + // load + row0 = vld1q_s16(data + 0 * 8); + row1 = vld1q_s16(data + 1 * 8); + row2 = vld1q_s16(data + 2 * 8); + row3 = vld1q_s16(data + 3 * 8); + row4 = vld1q_s16(data + 4 * 8); + row5 = vld1q_s16(data + 5 * 8); + row6 = vld1q_s16(data + 6 * 8); + row7 = vld1q_s16(data + 7 * 8); + + // add DC bias + row0 = vaddq_s16(row0, vsetq_lane_s16(1024, vdupq_n_s16(0), 0)); + + // column pass + dct_pass(vrshrn_n_s32, 10); + + // 16bit 8x8 transpose + { + // these three map to a single VTRN.16, VTRN.32, and VSWP, respectively. + // whether compilers actually get this is another story, sadly. +#define dct_trn16(x, y) { int16x8x2_t t = vtrnq_s16(x, y); x = t.val[0]; y = t.val[1]; } +#define dct_trn32(x, y) { int32x4x2_t t = vtrnq_s32(vreinterpretq_s32_s16(x), vreinterpretq_s32_s16(y)); x = vreinterpretq_s16_s32(t.val[0]); y = vreinterpretq_s16_s32(t.val[1]); } +#define dct_trn64(x, y) { int16x8_t x0 = x; int16x8_t y0 = y; x = vcombine_s16(vget_low_s16(x0), vget_low_s16(y0)); y = vcombine_s16(vget_high_s16(x0), vget_high_s16(y0)); } + + // pass 1 + dct_trn16(row0, row1); // a0b0a2b2a4b4a6b6 + dct_trn16(row2, row3); + dct_trn16(row4, row5); + dct_trn16(row6, row7); + + // pass 2 + dct_trn32(row0, row2); // a0b0c0d0a4b4c4d4 + dct_trn32(row1, row3); + dct_trn32(row4, row6); + dct_trn32(row5, row7); + + // pass 3 + dct_trn64(row0, row4); // a0b0c0d0e0f0g0h0 + dct_trn64(row1, row5); + dct_trn64(row2, row6); + dct_trn64(row3, row7); + +#undef dct_trn16 +#undef dct_trn32 +#undef dct_trn64 + } + + // row pass + // vrshrn_n_s32 only supports shifts up to 16, we need + // 17. so do a non-rounding shift of 16 first then follow + // up with a rounding shift by 1. + dct_pass(vshrn_n_s32, 16); + + { + // pack and round + uint8x8_t p0 = vqrshrun_n_s16(row0, 1); + uint8x8_t p1 = vqrshrun_n_s16(row1, 1); + uint8x8_t p2 = vqrshrun_n_s16(row2, 1); + uint8x8_t p3 = vqrshrun_n_s16(row3, 1); + uint8x8_t p4 = vqrshrun_n_s16(row4, 1); + uint8x8_t p5 = vqrshrun_n_s16(row5, 1); + uint8x8_t p6 = vqrshrun_n_s16(row6, 1); + uint8x8_t p7 = vqrshrun_n_s16(row7, 1); + + // again, these can translate into one instruction, but often don't. +#define dct_trn8_8(x, y) { uint8x8x2_t t = vtrn_u8(x, y); x = t.val[0]; y = t.val[1]; } +#define dct_trn8_16(x, y) { uint16x4x2_t t = vtrn_u16(vreinterpret_u16_u8(x), vreinterpret_u16_u8(y)); x = vreinterpret_u8_u16(t.val[0]); y = vreinterpret_u8_u16(t.val[1]); } +#define dct_trn8_32(x, y) { uint32x2x2_t t = vtrn_u32(vreinterpret_u32_u8(x), vreinterpret_u32_u8(y)); x = vreinterpret_u8_u32(t.val[0]); y = vreinterpret_u8_u32(t.val[1]); } + + // sadly can't use interleaved stores here since we only write + // 8 bytes to each scan line! + + // 8x8 8-bit transpose pass 1 + dct_trn8_8(p0, p1); + dct_trn8_8(p2, p3); + dct_trn8_8(p4, p5); + dct_trn8_8(p6, p7); + + // pass 2 + dct_trn8_16(p0, p2); + dct_trn8_16(p1, p3); + dct_trn8_16(p4, p6); + dct_trn8_16(p5, p7); + + // pass 3 + dct_trn8_32(p0, p4); + dct_trn8_32(p1, p5); + dct_trn8_32(p2, p6); + dct_trn8_32(p3, p7); + + // store + vst1_u8(out, p0); out += out_stride; + vst1_u8(out, p1); out += out_stride; + vst1_u8(out, p2); out += out_stride; + vst1_u8(out, p3); out += out_stride; + vst1_u8(out, p4); out += out_stride; + vst1_u8(out, p5); out += out_stride; + vst1_u8(out, p6); out += out_stride; + vst1_u8(out, p7); + +#undef dct_trn8_8 +#undef dct_trn8_16 +#undef dct_trn8_32 + } + +#undef dct_long_mul +#undef dct_long_mac +#undef dct_widen +#undef dct_wadd +#undef dct_wsub +#undef dct_bfly32o +#undef dct_pass +} + +#endif // STBI_NEON + +#define STBI__MARKER_none 0xff +// if there's a pending marker from the entropy stream, return that +// otherwise, fetch from the stream and get a marker. if there's no +// marker, return 0xff, which is never a valid marker value +static stbi_uc stbi__get_marker(stbi__jpeg *j) +{ + stbi_uc x; + if (j->marker != STBI__MARKER_none) { x = j->marker; j->marker = STBI__MARKER_none; return x; } + x = stbi__get8(j->s); + if (x != 0xff) return STBI__MARKER_none; + while (x == 0xff) + x = stbi__get8(j->s); + return x; +} + +// in each scan, we'll have scan_n components, and the order +// of the components is specified by order[] +#define STBI__RESTART(x) ((x) >= 0xd0 && (x) <= 0xd7) + +// after a restart interval, stbi__jpeg_reset the entropy decoder and +// the dc prediction +static void stbi__jpeg_reset(stbi__jpeg *j) +{ + j->code_bits = 0; + j->code_buffer = 0; + j->nomore = 0; + j->img_comp[0].dc_pred = j->img_comp[1].dc_pred = j->img_comp[2].dc_pred = 0; + j->marker = STBI__MARKER_none; + j->todo = j->restart_interval ? j->restart_interval : 0x7fffffff; + j->eob_run = 0; + // no more than 1<<31 MCUs if no restart_interal? that's plenty safe, + // since we don't even allow 1<<30 pixels +} + +static int stbi__parse_entropy_coded_data(stbi__jpeg *z) +{ + stbi__jpeg_reset(z); + if (!z->progressive) { + if (z->scan_n == 1) { + int i, j; + STBI_SIMD_ALIGN(short, data[64]); + int n = z->order[0]; + // non-interleaved data, we just need to process one block at a time, + // in trivial scanline order + // number of blocks to do just depends on how many actual "pixels" this + // component has, independent of interleaved MCU blocking and such + int w = (z->img_comp[n].x + 7) >> 3; + int h = (z->img_comp[n].y + 7) >> 3; + for (j = 0; j < h; ++j) { + for (i = 0; i < w; ++i) { + int ha = z->img_comp[n].ha; + if (!stbi__jpeg_decode_block(z, data, z->huff_dc + z->img_comp[n].hd, z->huff_ac + ha, z->fast_ac[ha], n, z->dequant[z->img_comp[n].tq])) return 0; + z->idct_block_kernel(z->img_comp[n].data + z->img_comp[n].w2*j * 8 + i * 8, z->img_comp[n].w2, data); + // every data block is an MCU, so countdown the restart interval + if (--z->todo <= 0) { + if (z->code_bits < 24) stbi__grow_buffer_unsafe(z); + // if it's NOT a restart, then just bail, so we get corrupt data + // rather than no data + if (!STBI__RESTART(z->marker)) return 1; + stbi__jpeg_reset(z); + } + } + } + return 1; + } + else { // interleaved + int i, j, k, x, y; + STBI_SIMD_ALIGN(short, data[64]); + for (j = 0; j < z->img_mcu_y; ++j) { + for (i = 0; i < z->img_mcu_x; ++i) { + // scan an interleaved mcu... process scan_n components in order + for (k = 0; k < z->scan_n; ++k) { + int n = z->order[k]; + // scan out an mcu's worth of this component; that's just determined + // by the basic H and V specified for the component + for (y = 0; y < z->img_comp[n].v; ++y) { + for (x = 0; x < z->img_comp[n].h; ++x) { + int x2 = (i*z->img_comp[n].h + x) * 8; + int y2 = (j*z->img_comp[n].v + y) * 8; + int ha = z->img_comp[n].ha; + if (!stbi__jpeg_decode_block(z, data, z->huff_dc + z->img_comp[n].hd, z->huff_ac + ha, z->fast_ac[ha], n, z->dequant[z->img_comp[n].tq])) return 0; + z->idct_block_kernel(z->img_comp[n].data + z->img_comp[n].w2*y2 + x2, z->img_comp[n].w2, data); + } + } + } + // after all interleaved components, that's an interleaved MCU, + // so now count down the restart interval + if (--z->todo <= 0) { + if (z->code_bits < 24) stbi__grow_buffer_unsafe(z); + if (!STBI__RESTART(z->marker)) return 1; + stbi__jpeg_reset(z); + } + } + } + return 1; + } + } + else { + if (z->scan_n == 1) { + int i, j; + int n = z->order[0]; + // non-interleaved data, we just need to process one block at a time, + // in trivial scanline order + // number of blocks to do just depends on how many actual "pixels" this + // component has, independent of interleaved MCU blocking and such + int w = (z->img_comp[n].x + 7) >> 3; + int h = (z->img_comp[n].y + 7) >> 3; + for (j = 0; j < h; ++j) { + for (i = 0; i < w; ++i) { + short *data = z->img_comp[n].coeff + 64 * (i + j * z->img_comp[n].coeff_w); + if (z->spec_start == 0) { + if (!stbi__jpeg_decode_block_prog_dc(z, data, &z->huff_dc[z->img_comp[n].hd], n)) + return 0; + } + else { + int ha = z->img_comp[n].ha; + if (!stbi__jpeg_decode_block_prog_ac(z, data, &z->huff_ac[ha], z->fast_ac[ha])) + return 0; + } + // every data block is an MCU, so countdown the restart interval + if (--z->todo <= 0) { + if (z->code_bits < 24) stbi__grow_buffer_unsafe(z); + if (!STBI__RESTART(z->marker)) return 1; + stbi__jpeg_reset(z); + } + } + } + return 1; + } + else { // interleaved + int i, j, k, x, y; + for (j = 0; j < z->img_mcu_y; ++j) { + for (i = 0; i < z->img_mcu_x; ++i) { + // scan an interleaved mcu... process scan_n components in order + for (k = 0; k < z->scan_n; ++k) { + int n = z->order[k]; + // scan out an mcu's worth of this component; that's just determined + // by the basic H and V specified for the component + for (y = 0; y < z->img_comp[n].v; ++y) { + for (x = 0; x < z->img_comp[n].h; ++x) { + int x2 = (i*z->img_comp[n].h + x); + int y2 = (j*z->img_comp[n].v + y); + short *data = z->img_comp[n].coeff + 64 * (x2 + y2 * z->img_comp[n].coeff_w); + if (!stbi__jpeg_decode_block_prog_dc(z, data, &z->huff_dc[z->img_comp[n].hd], n)) + return 0; + } + } + } + // after all interleaved components, that's an interleaved MCU, + // so now count down the restart interval + if (--z->todo <= 0) { + if (z->code_bits < 24) stbi__grow_buffer_unsafe(z); + if (!STBI__RESTART(z->marker)) return 1; + stbi__jpeg_reset(z); + } + } + } + return 1; + } + } +} + +static void stbi__jpeg_dequantize(short *data, stbi_uc *dequant) +{ + int i; + for (i = 0; i < 64; ++i) + data[i] *= dequant[i]; +} + +static void stbi__jpeg_finish(stbi__jpeg *z) +{ + if (z->progressive) { + // dequantize and idct the data + int i, j, n; + for (n = 0; n < z->s->img_n; ++n) { + int w = (z->img_comp[n].x + 7) >> 3; + int h = (z->img_comp[n].y + 7) >> 3; + for (j = 0; j < h; ++j) { + for (i = 0; i < w; ++i) { + short *data = z->img_comp[n].coeff + 64 * (i + j * z->img_comp[n].coeff_w); + stbi__jpeg_dequantize(data, z->dequant[z->img_comp[n].tq]); + z->idct_block_kernel(z->img_comp[n].data + z->img_comp[n].w2*j * 8 + i * 8, z->img_comp[n].w2, data); + } + } + } + } +} + +static int stbi__process_marker(stbi__jpeg *z, int m) +{ + int L; + switch (m) { + case STBI__MARKER_none: // no marker found + return stbi__err("expected marker", "Corrupt JPEG"); + + case 0xDD: // DRI - specify restart interval + if (stbi__get16be(z->s) != 4) return stbi__err("bad DRI len", "Corrupt JPEG"); + z->restart_interval = stbi__get16be(z->s); + return 1; + + case 0xDB: // DQT - define quantization table + L = stbi__get16be(z->s) - 2; + while (L > 0) { + int q = stbi__get8(z->s); + int p = q >> 4; + int t = q & 15, i; + if (p != 0) return stbi__err("bad DQT type", "Corrupt JPEG"); + if (t > 3) return stbi__err("bad DQT table", "Corrupt JPEG"); + for (i = 0; i < 64; ++i) + z->dequant[t][stbi__jpeg_dezigzag[i]] = stbi__get8(z->s); + L -= 65; + } + return L == 0; + + case 0xC4: // DHT - define huffman table + L = stbi__get16be(z->s) - 2; + while (L > 0) { + stbi_uc *v; + int sizes[16], i, n = 0; + int q = stbi__get8(z->s); + int tc = q >> 4; + int th = q & 15; + if (tc > 1 || th > 3) return stbi__err("bad DHT header", "Corrupt JPEG"); + for (i = 0; i < 16; ++i) { + sizes[i] = stbi__get8(z->s); + n += sizes[i]; + } + L -= 17; + if (tc == 0) { + if (!stbi__build_huffman(z->huff_dc + th, sizes)) return 0; + v = z->huff_dc[th].values; + } + else { + if (!stbi__build_huffman(z->huff_ac + th, sizes)) return 0; + v = z->huff_ac[th].values; + } + for (i = 0; i < n; ++i) + v[i] = stbi__get8(z->s); + if (tc != 0) + stbi__build_fast_ac(z->fast_ac[th], z->huff_ac + th); + L -= n; + } + return L == 0; + } + // check for comment block or APP blocks + if ((m >= 0xE0 && m <= 0xEF) || m == 0xFE) { + stbi__skip(z->s, stbi__get16be(z->s) - 2); + return 1; + } + return 0; +} + +// after we see SOS +static int stbi__process_scan_header(stbi__jpeg *z) +{ + int i; + int Ls = stbi__get16be(z->s); + z->scan_n = stbi__get8(z->s); + if (z->scan_n < 1 || z->scan_n > 4 || z->scan_n > (int)z->s->img_n) return stbi__err("bad SOS component count", "Corrupt JPEG"); + if (Ls != 6 + 2 * z->scan_n) return stbi__err("bad SOS len", "Corrupt JPEG"); + for (i = 0; i < z->scan_n; ++i) { + int id = stbi__get8(z->s), which; + int q = stbi__get8(z->s); + for (which = 0; which < z->s->img_n; ++which) + if (z->img_comp[which].id == id) + break; + if (which == z->s->img_n) return 0; // no match + z->img_comp[which].hd = q >> 4; if (z->img_comp[which].hd > 3) return stbi__err("bad DC huff", "Corrupt JPEG"); + z->img_comp[which].ha = q & 15; if (z->img_comp[which].ha > 3) return stbi__err("bad AC huff", "Corrupt JPEG"); + z->order[i] = which; + } + + { + int aa; + z->spec_start = stbi__get8(z->s); + z->spec_end = stbi__get8(z->s); // should be 63, but might be 0 + aa = stbi__get8(z->s); + z->succ_high = (aa >> 4); + z->succ_low = (aa & 15); + if (z->progressive) { + if (z->spec_start > 63 || z->spec_end > 63 || z->spec_start > z->spec_end || z->succ_high > 13 || z->succ_low > 13) + return stbi__err("bad SOS", "Corrupt JPEG"); + } + else { + if (z->spec_start != 0) return stbi__err("bad SOS", "Corrupt JPEG"); + if (z->succ_high != 0 || z->succ_low != 0) return stbi__err("bad SOS", "Corrupt JPEG"); + z->spec_end = 63; + } + } + + return 1; +} + +static int stbi__process_frame_header(stbi__jpeg *z, int scan) +{ + stbi__context *s = z->s; + int Lf, p, i, q, h_max = 1, v_max = 1, c; + Lf = stbi__get16be(s); if (Lf < 11) return stbi__err("bad SOF len", "Corrupt JPEG"); // JPEG + p = stbi__get8(s); if (p != 8) return stbi__err("only 8-bit", "JPEG format not supported: 8-bit only"); // JPEG baseline + s->img_y = stbi__get16be(s); if (s->img_y == 0) return stbi__err("no header height", "JPEG format not supported: delayed height"); // Legal, but we don't handle it--but neither does IJG + s->img_x = stbi__get16be(s); if (s->img_x == 0) return stbi__err("0 width", "Corrupt JPEG"); // JPEG requires + c = stbi__get8(s); + if (c != 3 && c != 1) return stbi__err("bad component count", "Corrupt JPEG"); // JFIF requires + s->img_n = c; + for (i = 0; i < c; ++i) { + z->img_comp[i].data = NULL; + z->img_comp[i].linebuf = NULL; + } + + if (Lf != 8 + 3 * s->img_n) return stbi__err("bad SOF len", "Corrupt JPEG"); + + for (i = 0; i < s->img_n; ++i) { + z->img_comp[i].id = stbi__get8(s); + if (z->img_comp[i].id != i + 1) // JFIF requires + if (z->img_comp[i].id != i) // some version of jpegtran outputs non-JFIF-compliant files! + return stbi__err("bad component ID", "Corrupt JPEG"); + q = stbi__get8(s); + z->img_comp[i].h = (q >> 4); if (!z->img_comp[i].h || z->img_comp[i].h > 4) return stbi__err("bad H", "Corrupt JPEG"); + z->img_comp[i].v = q & 15; if (!z->img_comp[i].v || z->img_comp[i].v > 4) return stbi__err("bad V", "Corrupt JPEG"); + z->img_comp[i].tq = stbi__get8(s); if (z->img_comp[i].tq > 3) return stbi__err("bad TQ", "Corrupt JPEG"); + } + + if (scan != STBI__SCAN_load) return 1; + + if ((1 << 30) / s->img_x / s->img_n < s->img_y) return stbi__err("too large", "Image too large to decode"); + + for (i = 0; i < s->img_n; ++i) { + if (z->img_comp[i].h > h_max) h_max = z->img_comp[i].h; + if (z->img_comp[i].v > v_max) v_max = z->img_comp[i].v; + } + + // compute interleaved mcu info + z->img_h_max = h_max; + z->img_v_max = v_max; + z->img_mcu_w = h_max * 8; + z->img_mcu_h = v_max * 8; + z->img_mcu_x = (s->img_x + z->img_mcu_w - 1) / z->img_mcu_w; + z->img_mcu_y = (s->img_y + z->img_mcu_h - 1) / z->img_mcu_h; + + for (i = 0; i < s->img_n; ++i) { + // number of effective pixels (e.g. for non-interleaved MCU) + z->img_comp[i].x = (s->img_x * z->img_comp[i].h + h_max - 1) / h_max; + z->img_comp[i].y = (s->img_y * z->img_comp[i].v + v_max - 1) / v_max; + // to simplify generation, we'll allocate enough memory to decode + // the bogus oversized data from using interleaved MCUs and their + // big blocks (e.g. a 16x16 iMCU on an image of width 33); we won't + // discard the extra data until colorspace conversion + z->img_comp[i].w2 = z->img_mcu_x * z->img_comp[i].h * 8; + z->img_comp[i].h2 = z->img_mcu_y * z->img_comp[i].v * 8; + z->img_comp[i].raw_data = stbi__malloc(z->img_comp[i].w2 * z->img_comp[i].h2 + 15); + + if (z->img_comp[i].raw_data == NULL) { + for (--i; i >= 0; --i) { + STBI_FREE(z->img_comp[i].raw_data); + z->img_comp[i].raw_data = NULL; + } + return stbi__err("outofmem", "Out of memory"); + } + // align blocks for idct using mmx/sse + z->img_comp[i].data = (stbi_uc*)(((size_t)z->img_comp[i].raw_data + 15) & ~15); + z->img_comp[i].linebuf = NULL; + if (z->progressive) { + z->img_comp[i].coeff_w = (z->img_comp[i].w2 + 7) >> 3; + z->img_comp[i].coeff_h = (z->img_comp[i].h2 + 7) >> 3; + z->img_comp[i].raw_coeff = STBI_MALLOC(z->img_comp[i].coeff_w * z->img_comp[i].coeff_h * 64 * sizeof(short) + 15); + z->img_comp[i].coeff = (short*)(((size_t)z->img_comp[i].raw_coeff + 15) & ~15); + } + else { + z->img_comp[i].coeff = 0; + z->img_comp[i].raw_coeff = 0; + } + } + + return 1; +} + +// use comparisons since in some cases we handle more than one case (e.g. SOF) +#define stbi__DNL(x) ((x) == 0xdc) +#define stbi__SOI(x) ((x) == 0xd8) +#define stbi__EOI(x) ((x) == 0xd9) +#define stbi__SOF(x) ((x) == 0xc0 || (x) == 0xc1 || (x) == 0xc2) +#define stbi__SOS(x) ((x) == 0xda) + +#define stbi__SOF_progressive(x) ((x) == 0xc2) + +static int stbi__decode_jpeg_header(stbi__jpeg *z, int scan) +{ + int m; + z->marker = STBI__MARKER_none; // initialize cached marker to empty + m = stbi__get_marker(z); + if (!stbi__SOI(m)) return stbi__err("no SOI", "Corrupt JPEG"); + if (scan == STBI__SCAN_type) return 1; + m = stbi__get_marker(z); + while (!stbi__SOF(m)) { + if (!stbi__process_marker(z, m)) return 0; + m = stbi__get_marker(z); + while (m == STBI__MARKER_none) { + // some files have extra padding after their blocks, so ok, we'll scan + if (stbi__at_eof(z->s)) return stbi__err("no SOF", "Corrupt JPEG"); + m = stbi__get_marker(z); + } + } + z->progressive = stbi__SOF_progressive(m); + if (!stbi__process_frame_header(z, scan)) return 0; + return 1; +} + +// decode image to YCbCr format +static int stbi__decode_jpeg_image(stbi__jpeg *j) +{ + int m; + for (m = 0; m < 4; m++) { + j->img_comp[m].raw_data = NULL; + j->img_comp[m].raw_coeff = NULL; + } + j->restart_interval = 0; + if (!stbi__decode_jpeg_header(j, STBI__SCAN_load)) return 0; + m = stbi__get_marker(j); + while (!stbi__EOI(m)) { + if (stbi__SOS(m)) { + if (!stbi__process_scan_header(j)) return 0; + if (!stbi__parse_entropy_coded_data(j)) return 0; + if (j->marker == STBI__MARKER_none) { + // handle 0s at the end of image data from IP Kamera 9060 + while (!stbi__at_eof(j->s)) { + int x = stbi__get8(j->s); + if (x == 255) { + j->marker = stbi__get8(j->s); + break; + } + else if (x != 0) { + return stbi__err("junk before marker", "Corrupt JPEG"); + } + } + // if we reach eof without hitting a marker, stbi__get_marker() below will fail and we'll eventually return 0 + } + } + else { + if (!stbi__process_marker(j, m)) return 0; + } + m = stbi__get_marker(j); + } + if (j->progressive) + stbi__jpeg_finish(j); + return 1; +} + +// static jfif-centered resampling (across block boundaries) + +typedef stbi_uc *(*resample_row_func)(stbi_uc *out, stbi_uc *in0, stbi_uc *in1, + int w, int hs); + +#define stbi__div4(x) ((stbi_uc) ((x) >> 2)) + +static stbi_uc *resample_row_1(stbi_uc *out, stbi_uc *in_near, stbi_uc *in_far, int w, int hs) +{ + STBI_NOTUSED(out); + STBI_NOTUSED(in_far); + STBI_NOTUSED(w); + STBI_NOTUSED(hs); + return in_near; +} + +static stbi_uc* stbi__resample_row_v_2(stbi_uc *out, stbi_uc *in_near, stbi_uc *in_far, int w, int hs) +{ + // need to generate two samples vertically for every one in input + int i; + STBI_NOTUSED(hs); + for (i = 0; i < w; ++i) + out[i] = stbi__div4(3 * in_near[i] + in_far[i] + 2); + return out; +} + +static stbi_uc* stbi__resample_row_h_2(stbi_uc *out, stbi_uc *in_near, stbi_uc *in_far, int w, int hs) +{ + // need to generate two samples horizontally for every one in input + int i; + stbi_uc *input = in_near; + + if (w == 1) { + // if only one sample, can't do any interpolation + out[0] = out[1] = input[0]; + return out; + } + + out[0] = input[0]; + out[1] = stbi__div4(input[0] * 3 + input[1] + 2); + for (i = 1; i < w - 1; ++i) { + int n = 3 * input[i] + 2; + out[i * 2 + 0] = stbi__div4(n + input[i - 1]); + out[i * 2 + 1] = stbi__div4(n + input[i + 1]); + } + out[i * 2 + 0] = stbi__div4(input[w - 2] * 3 + input[w - 1] + 2); + out[i * 2 + 1] = input[w - 1]; + + STBI_NOTUSED(in_far); + STBI_NOTUSED(hs); + + return out; +} + +#define stbi__div16(x) ((stbi_uc) ((x) >> 4)) + +static stbi_uc *stbi__resample_row_hv_2(stbi_uc *out, stbi_uc *in_near, stbi_uc *in_far, int w, int hs) +{ + // need to generate 2x2 samples for every one in input + int i, t0, t1; + if (w == 1) { + out[0] = out[1] = stbi__div4(3 * in_near[0] + in_far[0] + 2); + return out; + } + + t1 = 3 * in_near[0] + in_far[0]; + out[0] = stbi__div4(t1 + 2); + for (i = 1; i < w; ++i) { + t0 = t1; + t1 = 3 * in_near[i] + in_far[i]; + out[i * 2 - 1] = stbi__div16(3 * t0 + t1 + 8); + out[i * 2] = stbi__div16(3 * t1 + t0 + 8); + } + out[w * 2 - 1] = stbi__div4(t1 + 2); + + STBI_NOTUSED(hs); + + return out; +} + +#if defined(STBI_SSE2) || defined(STBI_NEON) +static stbi_uc *stbi__resample_row_hv_2_simd(stbi_uc *out, stbi_uc *in_near, stbi_uc *in_far, int w, int hs) +{ + // need to generate 2x2 samples for every one in input + int i = 0, t0, t1; + + if (w == 1) { + out[0] = out[1] = stbi__div4(3 * in_near[0] + in_far[0] + 2); + return out; + } + + t1 = 3 * in_near[0] + in_far[0]; + // process groups of 8 pixels for as long as we can. + // note we can't handle the last pixel in a row in this loop + // because we need to handle the filter boundary conditions. + for (; i < ((w - 1) & ~7); i += 8) { +#if defined(STBI_SSE2) + // load and perform the vertical filtering pass + // this uses 3*x + y = 4*x + (y - x) + __m128i zero = _mm_setzero_si128(); + __m128i farb = _mm_loadl_epi64((__m128i *) (in_far + i)); + __m128i nearb = _mm_loadl_epi64((__m128i *) (in_near + i)); + __m128i farw = _mm_unpacklo_epi8(farb, zero); + __m128i nearw = _mm_unpacklo_epi8(nearb, zero); + __m128i diff = _mm_sub_epi16(farw, nearw); + __m128i nears = _mm_slli_epi16(nearw, 2); + __m128i curr = _mm_add_epi16(nears, diff); // current row + + // horizontal filter works the same based on shifted vers of current + // row. "prev" is current row shifted right by 1 pixel; we need to + // insert the previous pixel value (from t1). + // "next" is current row shifted left by 1 pixel, with first pixel + // of next block of 8 pixels added in. + __m128i prv0 = _mm_slli_si128(curr, 2); + __m128i nxt0 = _mm_srli_si128(curr, 2); + __m128i prev = _mm_insert_epi16(prv0, t1, 0); + __m128i next = _mm_insert_epi16(nxt0, 3 * in_near[i + 8] + in_far[i + 8], 7); + + // horizontal filter, polyphase implementation since it's convenient: + // even pixels = 3*cur + prev = cur*4 + (prev - cur) + // odd pixels = 3*cur + next = cur*4 + (next - cur) + // note the shared term. + __m128i bias = _mm_set1_epi16(8); + __m128i curs = _mm_slli_epi16(curr, 2); + __m128i prvd = _mm_sub_epi16(prev, curr); + __m128i nxtd = _mm_sub_epi16(next, curr); + __m128i curb = _mm_add_epi16(curs, bias); + __m128i even = _mm_add_epi16(prvd, curb); + __m128i odd = _mm_add_epi16(nxtd, curb); + + // interleave even and odd pixels, then undo scaling. + __m128i int0 = _mm_unpacklo_epi16(even, odd); + __m128i int1 = _mm_unpackhi_epi16(even, odd); + __m128i de0 = _mm_srli_epi16(int0, 4); + __m128i de1 = _mm_srli_epi16(int1, 4); + + // pack and write output + __m128i outv = _mm_packus_epi16(de0, de1); + _mm_storeu_si128((__m128i *) (out + i * 2), outv); +#elif defined(STBI_NEON) + // load and perform the vertical filtering pass + // this uses 3*x + y = 4*x + (y - x) + uint8x8_t farb = vld1_u8(in_far + i); + uint8x8_t nearb = vld1_u8(in_near + i); + int16x8_t diff = vreinterpretq_s16_u16(vsubl_u8(farb, nearb)); + int16x8_t nears = vreinterpretq_s16_u16(vshll_n_u8(nearb, 2)); + int16x8_t curr = vaddq_s16(nears, diff); // current row + + // horizontal filter works the same based on shifted vers of current + // row. "prev" is current row shifted right by 1 pixel; we need to + // insert the previous pixel value (from t1). + // "next" is current row shifted left by 1 pixel, with first pixel + // of next block of 8 pixels added in. + int16x8_t prv0 = vextq_s16(curr, curr, 7); + int16x8_t nxt0 = vextq_s16(curr, curr, 1); + int16x8_t prev = vsetq_lane_s16(t1, prv0, 0); + int16x8_t next = vsetq_lane_s16(3 * in_near[i + 8] + in_far[i + 8], nxt0, 7); + + // horizontal filter, polyphase implementation since it's convenient: + // even pixels = 3*cur + prev = cur*4 + (prev - cur) + // odd pixels = 3*cur + next = cur*4 + (next - cur) + // note the shared term. + int16x8_t curs = vshlq_n_s16(curr, 2); + int16x8_t prvd = vsubq_s16(prev, curr); + int16x8_t nxtd = vsubq_s16(next, curr); + int16x8_t even = vaddq_s16(curs, prvd); + int16x8_t odd = vaddq_s16(curs, nxtd); + + // undo scaling and round, then store with even/odd phases interleaved + uint8x8x2_t o; + o.val[0] = vqrshrun_n_s16(even, 4); + o.val[1] = vqrshrun_n_s16(odd, 4); + vst2_u8(out + i * 2, o); +#endif + + // "previous" value for next iter + t1 = 3 * in_near[i + 7] + in_far[i + 7]; + } + + t0 = t1; + t1 = 3 * in_near[i] + in_far[i]; + out[i * 2] = stbi__div16(3 * t1 + t0 + 8); + + for (++i; i < w; ++i) { + t0 = t1; + t1 = 3 * in_near[i] + in_far[i]; + out[i * 2 - 1] = stbi__div16(3 * t0 + t1 + 8); + out[i * 2] = stbi__div16(3 * t1 + t0 + 8); + } + out[w * 2 - 1] = stbi__div4(t1 + 2); + + STBI_NOTUSED(hs); + + return out; +} +#endif + +static stbi_uc *stbi__resample_row_generic(stbi_uc *out, stbi_uc *in_near, stbi_uc *in_far, int w, int hs) +{ + // resample with nearest-neighbor + int i, j; + STBI_NOTUSED(in_far); + for (i = 0; i < w; ++i) + for (j = 0; j < hs; ++j) + out[i*hs + j] = in_near[i]; + return out; +} + +#ifdef STBI_JPEG_OLD +// this is the same YCbCr-to-RGB calculation that stb_image has used +// historically before the algorithm changes in 1.49 +#define float2fixed(x) ((int) ((x) * 65536 + 0.5)) +static void stbi__YCbCr_to_RGB_row(stbi_uc *out, const stbi_uc *y, const stbi_uc *pcb, const stbi_uc *pcr, int count, int step) +{ + int i; + for (i = 0; i < count; ++i) { + int y_fixed = (y[i] << 16) + 32768; // rounding + int r, g, b; + int cr = pcr[i] - 128; + int cb = pcb[i] - 128; + r = y_fixed + cr*float2fixed(1.40200f); + g = y_fixed - cr*float2fixed(0.71414f) - cb*float2fixed(0.34414f); + b = y_fixed + cb*float2fixed(1.77200f); + r >>= 16; + g >>= 16; + b >>= 16; + if ((unsigned)r > 255) { if (r < 0) r = 0; else r = 255; } + if ((unsigned)g > 255) { if (g < 0) g = 0; else g = 255; } + if ((unsigned)b > 255) { if (b < 0) b = 0; else b = 255; } + out[0] = (stbi_uc)r; + out[1] = (stbi_uc)g; + out[2] = (stbi_uc)b; + out[3] = 255; + out += step; + } +} +#else +// this is a reduced-precision calculation of YCbCr-to-RGB introduced +// to make sure the code produces the same results in both SIMD and scalar +#define float2fixed(x) (((int) ((x) * 4096.0f + 0.5f)) << 8) +static void stbi__YCbCr_to_RGB_row(stbi_uc *out, const stbi_uc *y, const stbi_uc *pcb, const stbi_uc *pcr, int count, int step) +{ + int i; + for (i = 0; i < count; ++i) { + int y_fixed = (y[i] << 20) + (1 << 19); // rounding + int r, g, b; + int cr = pcr[i] - 128; + int cb = pcb[i] - 128; + r = y_fixed + cr* float2fixed(1.40200f); + g = y_fixed + (cr*-float2fixed(0.71414f)) + ((cb*-float2fixed(0.34414f)) & 0xffff0000); + b = y_fixed + cb* float2fixed(1.77200f); + r >>= 20; + g >>= 20; + b >>= 20; + if ((unsigned)r > 255) { if (r < 0) r = 0; else r = 255; } + if ((unsigned)g > 255) { if (g < 0) g = 0; else g = 255; } + if ((unsigned)b > 255) { if (b < 0) b = 0; else b = 255; } + out[0] = (stbi_uc)r; + out[1] = (stbi_uc)g; + out[2] = (stbi_uc)b; + out[3] = 255; + out += step; + } +} +#endif + +#if defined(STBI_SSE2) || defined(STBI_NEON) +static void stbi__YCbCr_to_RGB_simd(stbi_uc *out, stbi_uc const *y, stbi_uc const *pcb, stbi_uc const *pcr, int count, int step) +{ + int i = 0; + +#ifdef STBI_SSE2 + // step == 3 is pretty ugly on the final interleave, and i'm not convinced + // it's useful in practice (you wouldn't use it for textures, for example). + // so just accelerate step == 4 case. + if (step == 4) { + // this is a fairly straightforward implementation and not super-optimized. + __m128i signflip = _mm_set1_epi8(-0x80); + __m128i cr_const0 = _mm_set1_epi16((short)(1.40200f*4096.0f + 0.5f)); + __m128i cr_const1 = _mm_set1_epi16(-(short)(0.71414f*4096.0f + 0.5f)); + __m128i cb_const0 = _mm_set1_epi16(-(short)(0.34414f*4096.0f + 0.5f)); + __m128i cb_const1 = _mm_set1_epi16((short)(1.77200f*4096.0f + 0.5f)); + __m128i y_bias = _mm_set1_epi8((char)(unsigned char)128); + __m128i xw = _mm_set1_epi16(255); // alpha channel + + for (; i + 7 < count; i += 8) { + // load + __m128i y_bytes = _mm_loadl_epi64((__m128i *) (y + i)); + __m128i cr_bytes = _mm_loadl_epi64((__m128i *) (pcr + i)); + __m128i cb_bytes = _mm_loadl_epi64((__m128i *) (pcb + i)); + __m128i cr_biased = _mm_xor_si128(cr_bytes, signflip); // -128 + __m128i cb_biased = _mm_xor_si128(cb_bytes, signflip); // -128 + + // unpack to short (and left-shift cr, cb by 8) + __m128i yw = _mm_unpacklo_epi8(y_bias, y_bytes); + __m128i crw = _mm_unpacklo_epi8(_mm_setzero_si128(), cr_biased); + __m128i cbw = _mm_unpacklo_epi8(_mm_setzero_si128(), cb_biased); + + // color transform + __m128i yws = _mm_srli_epi16(yw, 4); + __m128i cr0 = _mm_mulhi_epi16(cr_const0, crw); + __m128i cb0 = _mm_mulhi_epi16(cb_const0, cbw); + __m128i cb1 = _mm_mulhi_epi16(cbw, cb_const1); + __m128i cr1 = _mm_mulhi_epi16(crw, cr_const1); + __m128i rws = _mm_add_epi16(cr0, yws); + __m128i gwt = _mm_add_epi16(cb0, yws); + __m128i bws = _mm_add_epi16(yws, cb1); + __m128i gws = _mm_add_epi16(gwt, cr1); + + // descale + __m128i rw = _mm_srai_epi16(rws, 4); + __m128i bw = _mm_srai_epi16(bws, 4); + __m128i gw = _mm_srai_epi16(gws, 4); + + // back to byte, set up for transpose + __m128i brb = _mm_packus_epi16(rw, bw); + __m128i gxb = _mm_packus_epi16(gw, xw); + + // transpose to interleave channels + __m128i t0 = _mm_unpacklo_epi8(brb, gxb); + __m128i t1 = _mm_unpackhi_epi8(brb, gxb); + __m128i o0 = _mm_unpacklo_epi16(t0, t1); + __m128i o1 = _mm_unpackhi_epi16(t0, t1); + + // store + _mm_storeu_si128((__m128i *) (out + 0), o0); + _mm_storeu_si128((__m128i *) (out + 16), o1); + out += 32; + } + } +#endif + +#ifdef STBI_NEON + // in this version, step=3 support would be easy to add. but is there demand? + if (step == 4) { + // this is a fairly straightforward implementation and not super-optimized. + uint8x8_t signflip = vdup_n_u8(0x80); + int16x8_t cr_const0 = vdupq_n_s16((short)(1.40200f*4096.0f + 0.5f)); + int16x8_t cr_const1 = vdupq_n_s16(-(short)(0.71414f*4096.0f + 0.5f)); + int16x8_t cb_const0 = vdupq_n_s16(-(short)(0.34414f*4096.0f + 0.5f)); + int16x8_t cb_const1 = vdupq_n_s16((short)(1.77200f*4096.0f + 0.5f)); + + for (; i + 7 < count; i += 8) { + // load + uint8x8_t y_bytes = vld1_u8(y + i); + uint8x8_t cr_bytes = vld1_u8(pcr + i); + uint8x8_t cb_bytes = vld1_u8(pcb + i); + int8x8_t cr_biased = vreinterpret_s8_u8(vsub_u8(cr_bytes, signflip)); + int8x8_t cb_biased = vreinterpret_s8_u8(vsub_u8(cb_bytes, signflip)); + + // expand to s16 + int16x8_t yws = vreinterpretq_s16_u16(vshll_n_u8(y_bytes, 4)); + int16x8_t crw = vshll_n_s8(cr_biased, 7); + int16x8_t cbw = vshll_n_s8(cb_biased, 7); + + // color transform + int16x8_t cr0 = vqdmulhq_s16(crw, cr_const0); + int16x8_t cb0 = vqdmulhq_s16(cbw, cb_const0); + int16x8_t cr1 = vqdmulhq_s16(crw, cr_const1); + int16x8_t cb1 = vqdmulhq_s16(cbw, cb_const1); + int16x8_t rws = vaddq_s16(yws, cr0); + int16x8_t gws = vaddq_s16(vaddq_s16(yws, cb0), cr1); + int16x8_t bws = vaddq_s16(yws, cb1); + + // undo scaling, round, convert to byte + uint8x8x4_t o; + o.val[0] = vqrshrun_n_s16(rws, 4); + o.val[1] = vqrshrun_n_s16(gws, 4); + o.val[2] = vqrshrun_n_s16(bws, 4); + o.val[3] = vdup_n_u8(255); + + // store, interleaving r/g/b/a + vst4_u8(out, o); + out += 8 * 4; + } + } +#endif + + for (; i < count; ++i) { + int y_fixed = (y[i] << 20) + (1 << 19); // rounding + int r, g, b; + int cr = pcr[i] - 128; + int cb = pcb[i] - 128; + r = y_fixed + cr* float2fixed(1.40200f); + g = y_fixed + cr*-float2fixed(0.71414f) + ((cb*-float2fixed(0.34414f)) & 0xffff0000); + b = y_fixed + cb* float2fixed(1.77200f); + r >>= 20; + g >>= 20; + b >>= 20; + if ((unsigned)r > 255) { if (r < 0) r = 0; else r = 255; } + if ((unsigned)g > 255) { if (g < 0) g = 0; else g = 255; } + if ((unsigned)b > 255) { if (b < 0) b = 0; else b = 255; } + out[0] = (stbi_uc)r; + out[1] = (stbi_uc)g; + out[2] = (stbi_uc)b; + out[3] = 255; + out += step; + } +} +#endif + +// set up the kernels +static void stbi__setup_jpeg(stbi__jpeg *j) +{ + j->idct_block_kernel = stbi__idct_block; + j->YCbCr_to_RGB_kernel = stbi__YCbCr_to_RGB_row; + j->resample_row_hv_2_kernel = stbi__resample_row_hv_2; + +#ifdef STBI_SSE2 + if (stbi__sse2_available()) { + j->idct_block_kernel = stbi__idct_simd; +#ifndef STBI_JPEG_OLD + j->YCbCr_to_RGB_kernel = stbi__YCbCr_to_RGB_simd; +#endif + j->resample_row_hv_2_kernel = stbi__resample_row_hv_2_simd; + } +#endif + +#ifdef STBI_NEON + j->idct_block_kernel = stbi__idct_simd; +#ifndef STBI_JPEG_OLD + j->YCbCr_to_RGB_kernel = stbi__YCbCr_to_RGB_simd; +#endif + j->resample_row_hv_2_kernel = stbi__resample_row_hv_2_simd; +#endif +} + +// clean up the temporary component buffers +static void stbi__cleanup_jpeg(stbi__jpeg *j) +{ + int i; + for (i = 0; i < j->s->img_n; ++i) { + if (j->img_comp[i].raw_data) { + STBI_FREE(j->img_comp[i].raw_data); + j->img_comp[i].raw_data = NULL; + j->img_comp[i].data = NULL; + } + if (j->img_comp[i].raw_coeff) { + STBI_FREE(j->img_comp[i].raw_coeff); + j->img_comp[i].raw_coeff = 0; + j->img_comp[i].coeff = 0; + } + if (j->img_comp[i].linebuf) { + STBI_FREE(j->img_comp[i].linebuf); + j->img_comp[i].linebuf = NULL; + } + } +} + +typedef struct +{ + resample_row_func resample; + stbi_uc *line0, *line1; + int hs, vs; // expansion factor in each axis + int w_lores; // horizontal pixels pre-expansion + int ystep; // how far through vertical expansion we are + int ypos; // which pre-expansion row we're on +} stbi__resample; + +static stbi_uc *load_jpeg_image(stbi__jpeg *z, int *out_x, int *out_y, int *comp, int req_comp) +{ + int n, decode_n; + z->s->img_n = 0; // make stbi__cleanup_jpeg safe + + // validate req_comp + if (req_comp < 0 || req_comp > 4) return stbi__errpuc("bad req_comp", "Internal error"); + + // load a jpeg image from whichever source, but leave in YCbCr format + if (!stbi__decode_jpeg_image(z)) { stbi__cleanup_jpeg(z); return NULL; } + + // determine actual number of components to generate + n = req_comp ? req_comp : z->s->img_n; + + if (z->s->img_n == 3 && n < 3) + decode_n = 1; + else + decode_n = z->s->img_n; + + // resample and color-convert + { + int k; + unsigned int i, j; + stbi_uc *output; + stbi_uc *coutput[4]; + + stbi__resample res_comp[4]; + + for (k = 0; k < decode_n; ++k) { + stbi__resample *r = &res_comp[k]; + + // allocate line buffer big enough for upsampling off the edges + // with upsample factor of 4 + z->img_comp[k].linebuf = (stbi_uc *)stbi__malloc(z->s->img_x + 3); + if (!z->img_comp[k].linebuf) { stbi__cleanup_jpeg(z); return stbi__errpuc("outofmem", "Out of memory"); } + + r->hs = z->img_h_max / z->img_comp[k].h; + r->vs = z->img_v_max / z->img_comp[k].v; + r->ystep = r->vs >> 1; + r->w_lores = (z->s->img_x + r->hs - 1) / r->hs; + r->ypos = 0; + r->line0 = r->line1 = z->img_comp[k].data; + + if (r->hs == 1 && r->vs == 1) r->resample = resample_row_1; + else if (r->hs == 1 && r->vs == 2) r->resample = stbi__resample_row_v_2; + else if (r->hs == 2 && r->vs == 1) r->resample = stbi__resample_row_h_2; + else if (r->hs == 2 && r->vs == 2) r->resample = z->resample_row_hv_2_kernel; + else r->resample = stbi__resample_row_generic; + } + + // can't error after this so, this is safe + output = (stbi_uc *)stbi__malloc(n * z->s->img_x * z->s->img_y + 1); + if (!output) { stbi__cleanup_jpeg(z); return stbi__errpuc("outofmem", "Out of memory"); } + + // now go ahead and resample + for (j = 0; j < z->s->img_y; ++j) { + stbi_uc *out = output + n * z->s->img_x * j; + for (k = 0; k < decode_n; ++k) { + stbi__resample *r = &res_comp[k]; + int y_bot = r->ystep >= (r->vs >> 1); + coutput[k] = r->resample(z->img_comp[k].linebuf, + y_bot ? r->line1 : r->line0, + y_bot ? r->line0 : r->line1, + r->w_lores, r->hs); + if (++r->ystep >= r->vs) { + r->ystep = 0; + r->line0 = r->line1; + if (++r->ypos < z->img_comp[k].y) + r->line1 += z->img_comp[k].w2; + } + } + if (n >= 3) { + stbi_uc *y = coutput[0]; + if (z->s->img_n == 3) { + z->YCbCr_to_RGB_kernel(out, y, coutput[1], coutput[2], z->s->img_x, n); + } + else + for (i = 0; i < z->s->img_x; ++i) { + out[0] = out[1] = out[2] = y[i]; + out[3] = 255; // not used if n==3 + out += n; + } + } + else { + stbi_uc *y = coutput[0]; + if (n == 1) + for (i = 0; i < z->s->img_x; ++i) out[i] = y[i]; + else + for (i = 0; i < z->s->img_x; ++i) *out++ = y[i], *out++ = 255; + } + } + stbi__cleanup_jpeg(z); + *out_x = z->s->img_x; + *out_y = z->s->img_y; + if (comp) *comp = z->s->img_n; // report original components, not output + return output; + } +} + +static unsigned char *stbi__jpeg_load(stbi__context *s, int *x, int *y, int *comp, int req_comp) +{ + stbi__jpeg j; + j.s = s; + stbi__setup_jpeg(&j); + return load_jpeg_image(&j, x, y, comp, req_comp); +} + +static int stbi__jpeg_test(stbi__context *s) +{ + int r; + stbi__jpeg j; + j.s = s; + stbi__setup_jpeg(&j); + r = stbi__decode_jpeg_header(&j, STBI__SCAN_type); + stbi__rewind(s); + return r; +} + +static int stbi__jpeg_info_raw(stbi__jpeg *j, int *x, int *y, int *comp) +{ + if (!stbi__decode_jpeg_header(j, STBI__SCAN_header)) { + stbi__rewind(j->s); + return 0; + } + if (x) *x = j->s->img_x; + if (y) *y = j->s->img_y; + if (comp) *comp = j->s->img_n; + return 1; +} + +static int stbi__jpeg_info(stbi__context *s, int *x, int *y, int *comp) +{ + stbi__jpeg j; + j.s = s; + return stbi__jpeg_info_raw(&j, x, y, comp); +} +#endif + +// public domain zlib decode v0.2 Sean Barrett 2006-11-18 +// simple implementation +// - all input must be provided in an upfront buffer +// - all output is written to a single output buffer (can malloc/realloc) +// performance +// - fast huffman + +#ifndef STBI_NO_ZLIB + +// fast-way is faster to check than jpeg huffman, but slow way is slower +#define STBI__ZFAST_BITS 9 // accelerate all cases in default tables +#define STBI__ZFAST_MASK ((1 << STBI__ZFAST_BITS) - 1) + +// zlib-style huffman encoding +// (jpegs packs from left, zlib from right, so can't share code) +typedef struct +{ + stbi__uint16 fast[1 << STBI__ZFAST_BITS]; + stbi__uint16 firstcode[16]; + int maxcode[17]; + stbi__uint16 firstsymbol[16]; + stbi_uc size[288]; + stbi__uint16 value[288]; +} stbi__zhuffman; + +stbi_inline static int stbi__bitreverse16(int n) +{ + n = ((n & 0xAAAA) >> 1) | ((n & 0x5555) << 1); + n = ((n & 0xCCCC) >> 2) | ((n & 0x3333) << 2); + n = ((n & 0xF0F0) >> 4) | ((n & 0x0F0F) << 4); + n = ((n & 0xFF00) >> 8) | ((n & 0x00FF) << 8); + return n; +} + +stbi_inline static int stbi__bit_reverse(int v, int bits) +{ + STBI_ASSERT(bits <= 16); + // to bit reverse n bits, reverse 16 and shift + // e.g. 11 bits, bit reverse and shift away 5 + return stbi__bitreverse16(v) >> (16 - bits); +} + +static int stbi__zbuild_huffman(stbi__zhuffman *z, stbi_uc *sizelist, int num) +{ + int i, k = 0; + int code, next_code[16], sizes[17]; + + // DEFLATE spec for generating codes + memset(sizes, 0, sizeof(sizes)); + memset(z->fast, 0, sizeof(z->fast)); + for (i = 0; i < num; ++i) + ++sizes[sizelist[i]]; + sizes[0] = 0; + for (i = 1; i < 16; ++i) + if (sizes[i] >(1 << i)) + return stbi__err("bad sizes", "Corrupt PNG"); + code = 0; + for (i = 1; i < 16; ++i) { + next_code[i] = code; + z->firstcode[i] = (stbi__uint16)code; + z->firstsymbol[i] = (stbi__uint16)k; + code = (code + sizes[i]); + if (sizes[i]) + if (code - 1 >= (1 << i)) return stbi__err("bad codelengths", "Corrupt PNG"); + z->maxcode[i] = code << (16 - i); // preshift for inner loop + code <<= 1; + k += sizes[i]; + } + z->maxcode[16] = 0x10000; // sentinel + for (i = 0; i < num; ++i) { + int s = sizelist[i]; + if (s) { + int c = next_code[s] - z->firstcode[s] + z->firstsymbol[s]; + stbi__uint16 fastv = (stbi__uint16)((s << 9) | i); + z->size[c] = (stbi_uc)s; + z->value[c] = (stbi__uint16)i; + if (s <= STBI__ZFAST_BITS) { + int j = stbi__bit_reverse(next_code[s], s); + while (j < (1 << STBI__ZFAST_BITS)) { + z->fast[j] = fastv; + j += (1 << s); + } + } + ++next_code[s]; + } + } + return 1; +} + +// zlib-from-memory implementation for PNG reading +// because PNG allows splitting the zlib stream arbitrarily, +// and it's annoying structurally to have PNG call ZLIB call PNG, +// we require PNG read all the IDATs and combine them into a single +// memory buffer + +typedef struct +{ + stbi_uc *zbuffer, *zbuffer_end; + int num_bits; + stbi__uint32 code_buffer; + + char *zout; + char *zout_start; + char *zout_end; + int z_expandable; + + stbi__zhuffman z_length, z_distance; +} stbi__zbuf; + +stbi_inline static stbi_uc stbi__zget8(stbi__zbuf *z) +{ + if (z->zbuffer >= z->zbuffer_end) return 0; + return *z->zbuffer++; +} + +static void stbi__fill_bits(stbi__zbuf *z) +{ + do { + STBI_ASSERT(z->code_buffer < (1U << z->num_bits)); + z->code_buffer |= (unsigned int)stbi__zget8(z) << z->num_bits; + z->num_bits += 8; + } while (z->num_bits <= 24); +} + +stbi_inline static unsigned int stbi__zreceive(stbi__zbuf *z, int n) +{ + unsigned int k; + if (z->num_bits < n) stbi__fill_bits(z); + k = z->code_buffer & ((1 << n) - 1); + z->code_buffer >>= n; + z->num_bits -= n; + return k; +} + +static int stbi__zhuffman_decode_slowpath(stbi__zbuf *a, stbi__zhuffman *z) +{ + int b, s, k; + // not resolved by fast table, so compute it the slow way + // use jpeg approach, which requires MSbits at top + k = stbi__bit_reverse(a->code_buffer, 16); + for (s = STBI__ZFAST_BITS + 1; ; ++s) + if (k < z->maxcode[s]) + break; + if (s == 16) return -1; // invalid code! + // code size is s, so: + b = (k >> (16 - s)) - z->firstcode[s] + z->firstsymbol[s]; + STBI_ASSERT(z->size[b] == s); + a->code_buffer >>= s; + a->num_bits -= s; + return z->value[b]; +} + +stbi_inline static int stbi__zhuffman_decode(stbi__zbuf *a, stbi__zhuffman *z) +{ + int b, s; + if (a->num_bits < 16) stbi__fill_bits(a); + b = z->fast[a->code_buffer & STBI__ZFAST_MASK]; + if (b) { + s = b >> 9; + a->code_buffer >>= s; + a->num_bits -= s; + return b & 511; + } + return stbi__zhuffman_decode_slowpath(a, z); +} + +static int stbi__zexpand(stbi__zbuf *z, char *zout, int n) // need to make room for n bytes +{ + char *q; + int cur, limit, old_limit; + z->zout = zout; + if (!z->z_expandable) return stbi__err("output buffer limit", "Corrupt PNG"); + cur = (int)(z->zout - z->zout_start); + limit = old_limit = (int)(z->zout_end - z->zout_start); + while (cur + n > limit) + limit *= 2; + q = (char *)STBI_REALLOC_SIZED(z->zout_start, old_limit, limit); + STBI_NOTUSED(old_limit); + if (q == NULL) return stbi__err("outofmem", "Out of memory"); + z->zout_start = q; + z->zout = q + cur; + z->zout_end = q + limit; + return 1; +} + +static int stbi__zlength_base[31] = { + 3,4,5,6,7,8,9,10,11,13, + 15,17,19,23,27,31,35,43,51,59, + 67,83,99,115,131,163,195,227,258,0,0 }; + +static int stbi__zlength_extra[31] = +{ 0,0,0,0,0,0,0,0,1,1,1,1,2,2,2,2,3,3,3,3,4,4,4,4,5,5,5,5,0,0,0 }; + +static int stbi__zdist_base[32] = { 1,2,3,4,5,7,9,13,17,25,33,49,65,97,129,193, +257,385,513,769,1025,1537,2049,3073,4097,6145,8193,12289,16385,24577,0,0 }; + +static int stbi__zdist_extra[32] = +{ 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 }; + +static int stbi__parse_huffman_block(stbi__zbuf *a) +{ + char *zout = a->zout; + for (;;) { + int z = stbi__zhuffman_decode(a, &a->z_length); + if (z < 256) { + if (z < 0) return stbi__err("bad huffman code", "Corrupt PNG"); // error in huffman codes + if (zout >= a->zout_end) { + if (!stbi__zexpand(a, zout, 1)) return 0; + zout = a->zout; + } + *zout++ = (char)z; + } + else { + stbi_uc *p; + int len, dist; + if (z == 256) { + a->zout = zout; + return 1; + } + z -= 257; + len = stbi__zlength_base[z]; + if (stbi__zlength_extra[z]) len += stbi__zreceive(a, stbi__zlength_extra[z]); + z = stbi__zhuffman_decode(a, &a->z_distance); + if (z < 0) return stbi__err("bad huffman code", "Corrupt PNG"); + dist = stbi__zdist_base[z]; + if (stbi__zdist_extra[z]) dist += stbi__zreceive(a, stbi__zdist_extra[z]); + if (zout - a->zout_start < dist) return stbi__err("bad dist", "Corrupt PNG"); + if (zout + len > a->zout_end) { + if (!stbi__zexpand(a, zout, len)) return 0; + zout = a->zout; + } + p = (stbi_uc *)(zout - dist); + if (dist == 1) { // run of one byte; common in images. + stbi_uc v = *p; + if (len) { do *zout++ = v; while (--len); } + } + else { + if (len) { do *zout++ = *p++; while (--len); } + } + } + } +} + +static int stbi__compute_huffman_codes(stbi__zbuf *a) +{ + static stbi_uc length_dezigzag[19] = { 16,17,18,0,8,7,9,6,10,5,11,4,12,3,13,2,14,1,15 }; + stbi__zhuffman z_codelength; + stbi_uc lencodes[286 + 32 + 137];//padding for maximum single op + stbi_uc codelength_sizes[19]; + int i, n; + + int hlit = stbi__zreceive(a, 5) + 257; + int hdist = stbi__zreceive(a, 5) + 1; + int hclen = stbi__zreceive(a, 4) + 4; + + memset(codelength_sizes, 0, sizeof(codelength_sizes)); + for (i = 0; i < hclen; ++i) { + int s = stbi__zreceive(a, 3); + codelength_sizes[length_dezigzag[i]] = (stbi_uc)s; + } + if (!stbi__zbuild_huffman(&z_codelength, codelength_sizes, 19)) return 0; + + n = 0; + while (n < hlit + hdist) { + int c = stbi__zhuffman_decode(a, &z_codelength); + if (c < 0 || c >= 19) return stbi__err("bad codelengths", "Corrupt PNG"); + if (c < 16) + lencodes[n++] = (stbi_uc)c; + else if (c == 16) { + c = stbi__zreceive(a, 2) + 3; + memset(lencodes + n, lencodes[n - 1], c); + n += c; + } + else if (c == 17) { + c = stbi__zreceive(a, 3) + 3; + memset(lencodes + n, 0, c); + n += c; + } + else { + STBI_ASSERT(c == 18); + c = stbi__zreceive(a, 7) + 11; + memset(lencodes + n, 0, c); + n += c; + } + } + if (n != hlit + hdist) return stbi__err("bad codelengths", "Corrupt PNG"); + if (!stbi__zbuild_huffman(&a->z_length, lencodes, hlit)) return 0; + if (!stbi__zbuild_huffman(&a->z_distance, lencodes + hlit, hdist)) return 0; + return 1; +} + +static int stbi__parse_uncomperssed_block(stbi__zbuf *a) +{ + stbi_uc header[4]; + int len, nlen, k; + if (a->num_bits & 7) + stbi__zreceive(a, a->num_bits & 7); // discard + // drain the bit-packed data into header + k = 0; + while (a->num_bits > 0) { + header[k++] = (stbi_uc)(a->code_buffer & 255); // suppress MSVC run-time check + a->code_buffer >>= 8; + a->num_bits -= 8; + } + STBI_ASSERT(a->num_bits == 0); + // now fill header the normal way + while (k < 4) + header[k++] = stbi__zget8(a); + len = header[1] * 256 + header[0]; + nlen = header[3] * 256 + header[2]; + if (nlen != (len ^ 0xffff)) return stbi__err("zlib corrupt", "Corrupt PNG"); + if (a->zbuffer + len > a->zbuffer_end) return stbi__err("read past buffer", "Corrupt PNG"); + if (a->zout + len > a->zout_end) + if (!stbi__zexpand(a, a->zout, len)) return 0; + memcpy(a->zout, a->zbuffer, len); + a->zbuffer += len; + a->zout += len; + return 1; +} + +static int stbi__parse_zlib_header(stbi__zbuf *a) +{ + int cmf = stbi__zget8(a); + int cm = cmf & 15; + /* int cinfo = cmf >> 4; */ + int flg = stbi__zget8(a); + if ((cmf * 256 + flg) % 31 != 0) return stbi__err("bad zlib header", "Corrupt PNG"); // zlib spec + if (flg & 32) return stbi__err("no preset dict", "Corrupt PNG"); // preset dictionary not allowed in png + if (cm != 8) return stbi__err("bad compression", "Corrupt PNG"); // DEFLATE required for png + // window = 1 << (8 + cinfo)... but who cares, we fully buffer output + return 1; +} + +// @TODO: should statically initialize these for optimal thread safety +static stbi_uc stbi__zdefault_length[288], stbi__zdefault_distance[32]; +static void stbi__init_zdefaults(void) +{ + int i; // use <= to match clearly with spec + for (i = 0; i <= 143; ++i) stbi__zdefault_length[i] = 8; + for (; i <= 255; ++i) stbi__zdefault_length[i] = 9; + for (; i <= 279; ++i) stbi__zdefault_length[i] = 7; + for (; i <= 287; ++i) stbi__zdefault_length[i] = 8; + + for (i = 0; i <= 31; ++i) stbi__zdefault_distance[i] = 5; +} + +static int stbi__parse_zlib(stbi__zbuf *a, int parse_header) +{ + int final, type; + if (parse_header) + if (!stbi__parse_zlib_header(a)) return 0; + a->num_bits = 0; + a->code_buffer = 0; + do { + final = stbi__zreceive(a, 1); + type = stbi__zreceive(a, 2); + if (type == 0) { + if (!stbi__parse_uncomperssed_block(a)) return 0; + } + else if (type == 3) { + return 0; + } + else { + if (type == 1) { + // use fixed code lengths + if (!stbi__zdefault_distance[31]) stbi__init_zdefaults(); + if (!stbi__zbuild_huffman(&a->z_length, stbi__zdefault_length, 288)) return 0; + if (!stbi__zbuild_huffman(&a->z_distance, stbi__zdefault_distance, 32)) return 0; + } + else { + if (!stbi__compute_huffman_codes(a)) return 0; + } + if (!stbi__parse_huffman_block(a)) return 0; + } + } while (!final); + return 1; +} + +static int stbi__do_zlib(stbi__zbuf *a, char *obuf, int olen, int exp, int parse_header) +{ + a->zout_start = obuf; + a->zout = obuf; + a->zout_end = obuf + olen; + a->z_expandable = exp; + + return stbi__parse_zlib(a, parse_header); +} + +STBIDEF char *stbi_zlib_decode_malloc_guesssize(const char *buffer, int len, int initial_size, int *outlen) +{ + stbi__zbuf a; + char *p = (char *)stbi__malloc(initial_size); + if (p == NULL) return NULL; + a.zbuffer = (stbi_uc *)buffer; + a.zbuffer_end = (stbi_uc *)buffer + len; + if (stbi__do_zlib(&a, p, initial_size, 1, 1)) { + if (outlen) *outlen = (int)(a.zout - a.zout_start); + return a.zout_start; + } + else { + STBI_FREE(a.zout_start); + return NULL; + } +} + +STBIDEF char *stbi_zlib_decode_malloc(char const *buffer, int len, int *outlen) +{ + return stbi_zlib_decode_malloc_guesssize(buffer, len, 16384, outlen); +} + +STBIDEF char *stbi_zlib_decode_malloc_guesssize_headerflag(const char *buffer, int len, int initial_size, int *outlen, int parse_header) +{ + stbi__zbuf a; + char *p = (char *)stbi__malloc(initial_size); + if (p == NULL) return NULL; + a.zbuffer = (stbi_uc *)buffer; + a.zbuffer_end = (stbi_uc *)buffer + len; + if (stbi__do_zlib(&a, p, initial_size, 1, parse_header)) { + if (outlen) *outlen = (int)(a.zout - a.zout_start); + return a.zout_start; + } + else { + STBI_FREE(a.zout_start); + return NULL; + } +} + +STBIDEF int stbi_zlib_decode_buffer(char *obuffer, int olen, char const *ibuffer, int ilen) +{ + stbi__zbuf a; + a.zbuffer = (stbi_uc *)ibuffer; + a.zbuffer_end = (stbi_uc *)ibuffer + ilen; + if (stbi__do_zlib(&a, obuffer, olen, 0, 1)) + return (int)(a.zout - a.zout_start); + else + return -1; +} + +STBIDEF char *stbi_zlib_decode_noheader_malloc(char const *buffer, int len, int *outlen) +{ + stbi__zbuf a; + char *p = (char *)stbi__malloc(16384); + if (p == NULL) return NULL; + a.zbuffer = (stbi_uc *)buffer; + a.zbuffer_end = (stbi_uc *)buffer + len; + if (stbi__do_zlib(&a, p, 16384, 1, 0)) { + if (outlen) *outlen = (int)(a.zout - a.zout_start); + return a.zout_start; + } + else { + STBI_FREE(a.zout_start); + return NULL; + } +} + +STBIDEF int stbi_zlib_decode_noheader_buffer(char *obuffer, int olen, const char *ibuffer, int ilen) +{ + stbi__zbuf a; + a.zbuffer = (stbi_uc *)ibuffer; + a.zbuffer_end = (stbi_uc *)ibuffer + ilen; + if (stbi__do_zlib(&a, obuffer, olen, 0, 0)) + return (int)(a.zout - a.zout_start); + else + return -1; +} +#endif + +// public domain "baseline" PNG decoder v0.10 Sean Barrett 2006-11-18 +// simple implementation +// - only 8-bit samples +// - no CRC checking +// - allocates lots of intermediate memory +// - avoids problem of streaming data between subsystems +// - avoids explicit window management +// performance +// - uses stb_zlib, a PD zlib implementation with fast huffman decoding + +#ifndef STBI_NO_PNG +typedef struct +{ + stbi__uint32 length; + stbi__uint32 type; +} stbi__pngchunk; + +static stbi__pngchunk stbi__get_chunk_header(stbi__context *s) +{ + stbi__pngchunk c; + c.length = stbi__get32be(s); + c.type = stbi__get32be(s); + return c; +} + +static int stbi__check_png_header(stbi__context *s) +{ + static stbi_uc png_sig[8] = { 137,80,78,71,13,10,26,10 }; + int i; + for (i = 0; i < 8; ++i) + if (stbi__get8(s) != png_sig[i]) return stbi__err("bad png sig", "Not a PNG"); + return 1; +} + +typedef struct +{ + stbi__context *s; + stbi_uc *idata, *expanded, *out; +} stbi__png; + + +enum { + STBI__F_none = 0, + STBI__F_sub = 1, + STBI__F_up = 2, + STBI__F_avg = 3, + STBI__F_paeth = 4, + // synthetic filters used for first scanline to avoid needing a dummy row of 0s + STBI__F_avg_first, + STBI__F_paeth_first +}; + +static stbi_uc first_row_filter[5] = +{ + STBI__F_none, + STBI__F_sub, + STBI__F_none, + STBI__F_avg_first, + STBI__F_paeth_first +}; + +static int stbi__paeth(int a, int b, int c) +{ + int p = a + b - c; + int pa = abs(p - a); + int pb = abs(p - b); + int pc = abs(p - c); + if (pa <= pb && pa <= pc) return a; + if (pb <= pc) return b; + return c; +} + +static stbi_uc stbi__depth_scale_table[9] = { 0, 0xff, 0x55, 0, 0x11, 0,0,0, 0x01 }; + +// create the png data from post-deflated data +static int stbi__create_png_image_raw(stbi__png *a, stbi_uc *raw, stbi__uint32 raw_len, int out_n, stbi__uint32 x, stbi__uint32 y, int depth, int color) +{ + stbi__context *s = a->s; + stbi__uint32 i, j, stride = x*out_n; + stbi__uint32 img_len, img_width_bytes; + int k; + int img_n = s->img_n; // copy it into a local for later + + STBI_ASSERT(out_n == s->img_n || out_n == s->img_n + 1); + a->out = (stbi_uc *)stbi__malloc(x * y * out_n); // extra bytes to write off the end into + if (!a->out) return stbi__err("outofmem", "Out of memory"); + + img_width_bytes = (((img_n * x * depth) + 7) >> 3); + img_len = (img_width_bytes + 1) * y; + if (s->img_x == x && s->img_y == y) { + if (raw_len != img_len) return stbi__err("not enough pixels", "Corrupt PNG"); + } + else { // interlaced: + if (raw_len < img_len) return stbi__err("not enough pixels", "Corrupt PNG"); + } + + for (j = 0; j < y; ++j) { + stbi_uc *cur = a->out + stride*j; + stbi_uc *prior = cur - stride; + int filter = *raw++; + int filter_bytes = img_n; + int width = x; + if (filter > 4) + return stbi__err("invalid filter", "Corrupt PNG"); + + if (depth < 8) { + STBI_ASSERT(img_width_bytes <= x); + cur += x*out_n - img_width_bytes; // store output to the rightmost img_len bytes, so we can decode in place + filter_bytes = 1; + width = img_width_bytes; + } + + // if first row, use special filter that doesn't sample previous row + if (j == 0) filter = first_row_filter[filter]; + + // handle first byte explicitly + for (k = 0; k < filter_bytes; ++k) { + switch (filter) { + case STBI__F_none: cur[k] = raw[k]; break; + case STBI__F_sub: cur[k] = raw[k]; break; + case STBI__F_up: cur[k] = STBI__BYTECAST(raw[k] + prior[k]); break; + case STBI__F_avg: cur[k] = STBI__BYTECAST(raw[k] + (prior[k] >> 1)); break; + case STBI__F_paeth: cur[k] = STBI__BYTECAST(raw[k] + stbi__paeth(0, prior[k], 0)); break; + case STBI__F_avg_first: cur[k] = raw[k]; break; + case STBI__F_paeth_first: cur[k] = raw[k]; break; + } + } + + if (depth == 8) { + if (img_n != out_n) + cur[img_n] = 255; // first pixel + raw += img_n; + cur += out_n; + prior += out_n; + } + else { + raw += 1; + cur += 1; + prior += 1; + } + + // this is a little gross, so that we don't switch per-pixel or per-component + if (depth < 8 || img_n == out_n) { + int nk = (width - 1)*img_n; +#define CASE(f) \ + case f: \ + for (k=0; k < nk; ++k) + switch (filter) { + // "none" filter turns into a memcpy here; make that explicit. + case STBI__F_none: memcpy(cur, raw, nk); break; + CASE(STBI__F_sub) cur[k] = STBI__BYTECAST(raw[k] + cur[k - filter_bytes]); break; + CASE(STBI__F_up) cur[k] = STBI__BYTECAST(raw[k] + prior[k]); break; + CASE(STBI__F_avg) cur[k] = STBI__BYTECAST(raw[k] + ((prior[k] + cur[k - filter_bytes]) >> 1)); break; + CASE(STBI__F_paeth) cur[k] = STBI__BYTECAST(raw[k] + stbi__paeth(cur[k - filter_bytes], prior[k], prior[k - filter_bytes])); break; + CASE(STBI__F_avg_first) cur[k] = STBI__BYTECAST(raw[k] + (cur[k - filter_bytes] >> 1)); break; + CASE(STBI__F_paeth_first) cur[k] = STBI__BYTECAST(raw[k] + stbi__paeth(cur[k - filter_bytes], 0, 0)); break; + } +#undef CASE + raw += nk; + } + else { + STBI_ASSERT(img_n + 1 == out_n); +#define CASE(f) \ + case f: \ + for (i=x-1; i >= 1; --i, cur[img_n]=255,raw+=img_n,cur+=out_n,prior+=out_n) \ + for (k=0; k < img_n; ++k) + switch (filter) { + CASE(STBI__F_none) cur[k] = raw[k]; break; + CASE(STBI__F_sub) cur[k] = STBI__BYTECAST(raw[k] + cur[k - out_n]); break; + CASE(STBI__F_up) cur[k] = STBI__BYTECAST(raw[k] + prior[k]); break; + CASE(STBI__F_avg) cur[k] = STBI__BYTECAST(raw[k] + ((prior[k] + cur[k - out_n]) >> 1)); break; + CASE(STBI__F_paeth) cur[k] = STBI__BYTECAST(raw[k] + stbi__paeth(cur[k - out_n], prior[k], prior[k - out_n])); break; + CASE(STBI__F_avg_first) cur[k] = STBI__BYTECAST(raw[k] + (cur[k - out_n] >> 1)); break; + CASE(STBI__F_paeth_first) cur[k] = STBI__BYTECAST(raw[k] + stbi__paeth(cur[k - out_n], 0, 0)); break; + } +#undef CASE + } + } + + // we make a separate pass to expand bits to pixels; for performance, + // this could run two scanlines behind the above code, so it won't + // intefere with filtering but will still be in the cache. + if (depth < 8) { + for (j = 0; j < y; ++j) { + stbi_uc *cur = a->out + stride*j; + stbi_uc *in = a->out + stride*j + x*out_n - img_width_bytes; + // unpack 1/2/4-bit into a 8-bit buffer. allows us to keep the common 8-bit path optimal at minimal cost for 1/2/4-bit + // png guarante byte alignment, if width is not multiple of 8/4/2 we'll decode dummy trailing data that will be skipped in the later loop + stbi_uc scale = (color == 0) ? stbi__depth_scale_table[depth] : 1; // scale grayscale values to 0..255 range + + // note that the final byte might overshoot and write more data than desired. + // we can allocate enough data that this never writes out of memory, but it + // could also overwrite the next scanline. can it overwrite non-empty data + // on the next scanline? yes, consider 1-pixel-wide scanlines with 1-bit-per-pixel. + // so we need to explicitly clamp the final ones + + if (depth == 4) { + for (k = x*img_n; k >= 2; k -= 2, ++in) { + *cur++ = scale * ((*in >> 4)); + *cur++ = scale * ((*in) & 0x0f); + } + if (k > 0) *cur++ = scale * ((*in >> 4)); + } + else if (depth == 2) { + for (k = x*img_n; k >= 4; k -= 4, ++in) { + *cur++ = scale * ((*in >> 6)); + *cur++ = scale * ((*in >> 4) & 0x03); + *cur++ = scale * ((*in >> 2) & 0x03); + *cur++ = scale * ((*in) & 0x03); + } + if (k > 0) *cur++ = scale * ((*in >> 6)); + if (k > 1) *cur++ = scale * ((*in >> 4) & 0x03); + if (k > 2) *cur++ = scale * ((*in >> 2) & 0x03); + } + else if (depth == 1) { + for (k = x*img_n; k >= 8; k -= 8, ++in) { + *cur++ = scale * ((*in >> 7)); + *cur++ = scale * ((*in >> 6) & 0x01); + *cur++ = scale * ((*in >> 5) & 0x01); + *cur++ = scale * ((*in >> 4) & 0x01); + *cur++ = scale * ((*in >> 3) & 0x01); + *cur++ = scale * ((*in >> 2) & 0x01); + *cur++ = scale * ((*in >> 1) & 0x01); + *cur++ = scale * ((*in) & 0x01); + } + if (k > 0) *cur++ = scale * ((*in >> 7)); + if (k > 1) *cur++ = scale * ((*in >> 6) & 0x01); + if (k > 2) *cur++ = scale * ((*in >> 5) & 0x01); + if (k > 3) *cur++ = scale * ((*in >> 4) & 0x01); + if (k > 4) *cur++ = scale * ((*in >> 3) & 0x01); + if (k > 5) *cur++ = scale * ((*in >> 2) & 0x01); + if (k > 6) *cur++ = scale * ((*in >> 1) & 0x01); + } + if (img_n != out_n) { + int q; + // insert alpha = 255 + cur = a->out + stride*j; + if (img_n == 1) { + for (q = x - 1; q >= 0; --q) { + cur[q * 2 + 1] = 255; + cur[q * 2 + 0] = cur[q]; + } + } + else { + STBI_ASSERT(img_n == 3); + for (q = x - 1; q >= 0; --q) { + cur[q * 4 + 3] = 255; + cur[q * 4 + 2] = cur[q * 3 + 2]; + cur[q * 4 + 1] = cur[q * 3 + 1]; + cur[q * 4 + 0] = cur[q * 3 + 0]; + } + } + } + } + } + + return 1; +} + +static int stbi__create_png_image(stbi__png *a, stbi_uc *image_data, stbi__uint32 image_data_len, int out_n, int depth, int color, int interlaced) +{ + stbi_uc *final; + int p; + if (!interlaced) + return stbi__create_png_image_raw(a, image_data, image_data_len, out_n, a->s->img_x, a->s->img_y, depth, color); + + // de-interlacing + final = (stbi_uc *)stbi__malloc(a->s->img_x * a->s->img_y * out_n); + for (p = 0; p < 7; ++p) { + int xorig[] = { 0,4,0,2,0,1,0 }; + int yorig[] = { 0,0,4,0,2,0,1 }; + int xspc[] = { 8,8,4,4,2,2,1 }; + int yspc[] = { 8,8,8,4,4,2,2 }; + int i, j, x, y; + // pass1_x[4] = 0, pass1_x[5] = 1, pass1_x[12] = 1 + x = (a->s->img_x - xorig[p] + xspc[p] - 1) / xspc[p]; + y = (a->s->img_y - yorig[p] + yspc[p] - 1) / yspc[p]; + if (x && y) { + stbi__uint32 img_len = ((((a->s->img_n * x * depth) + 7) >> 3) + 1) * y; + if (!stbi__create_png_image_raw(a, image_data, image_data_len, out_n, x, y, depth, color)) { + STBI_FREE(final); + return 0; + } + for (j = 0; j < y; ++j) { + for (i = 0; i < x; ++i) { + int out_y = j*yspc[p] + yorig[p]; + int out_x = i*xspc[p] + xorig[p]; + memcpy(final + out_y*a->s->img_x*out_n + out_x*out_n, + a->out + (j*x + i)*out_n, out_n); + } + } + STBI_FREE(a->out); + image_data += img_len; + image_data_len -= img_len; + } + } + a->out = final; + + return 1; +} + +static int stbi__compute_transparency(stbi__png *z, stbi_uc tc[3], int out_n) +{ + stbi__context *s = z->s; + stbi__uint32 i, pixel_count = s->img_x * s->img_y; + stbi_uc *p = z->out; + + // compute color-based transparency, assuming we've + // already got 255 as the alpha value in the output + STBI_ASSERT(out_n == 2 || out_n == 4); + + if (out_n == 2) { + for (i = 0; i < pixel_count; ++i) { + p[1] = (p[0] == tc[0] ? 0 : 255); + p += 2; + } + } + else { + for (i = 0; i < pixel_count; ++i) { + if (p[0] == tc[0] && p[1] == tc[1] && p[2] == tc[2]) + p[3] = 0; + p += 4; + } + } + return 1; +} + +static int stbi__expand_png_palette(stbi__png *a, stbi_uc *palette, int len, int pal_img_n) +{ + stbi__uint32 i, pixel_count = a->s->img_x * a->s->img_y; + stbi_uc *p, *temp_out, *orig = a->out; + + p = (stbi_uc *)stbi__malloc(pixel_count * pal_img_n); + if (p == NULL) return stbi__err("outofmem", "Out of memory"); + + // between here and free(out) below, exitting would leak + temp_out = p; + + if (pal_img_n == 3) { + for (i = 0; i < pixel_count; ++i) { + int n = orig[i] * 4; + p[0] = palette[n]; + p[1] = palette[n + 1]; + p[2] = palette[n + 2]; + p += 3; + } + } + else { + for (i = 0; i < pixel_count; ++i) { + int n = orig[i] * 4; + p[0] = palette[n]; + p[1] = palette[n + 1]; + p[2] = palette[n + 2]; + p[3] = palette[n + 3]; + p += 4; + } + } + STBI_FREE(a->out); + a->out = temp_out; + + STBI_NOTUSED(len); + + return 1; +} + +static int stbi__unpremultiply_on_load = 0; +static int stbi__de_iphone_flag = 0; + +STBIDEF void stbi_set_unpremultiply_on_load(int flag_true_if_should_unpremultiply) +{ + stbi__unpremultiply_on_load = flag_true_if_should_unpremultiply; +} + +STBIDEF void stbi_convert_iphone_png_to_rgb(int flag_true_if_should_convert) +{ + stbi__de_iphone_flag = flag_true_if_should_convert; +} + +static void stbi__de_iphone(stbi__png *z) +{ + stbi__context *s = z->s; + stbi__uint32 i, pixel_count = s->img_x * s->img_y; + stbi_uc *p = z->out; + + if (s->img_out_n == 3) { // convert bgr to rgb + for (i = 0; i < pixel_count; ++i) { + stbi_uc t = p[0]; + p[0] = p[2]; + p[2] = t; + p += 3; + } + } + else { + STBI_ASSERT(s->img_out_n == 4); + if (stbi__unpremultiply_on_load) { + // convert bgr to rgb and unpremultiply + for (i = 0; i < pixel_count; ++i) { + stbi_uc a = p[3]; + stbi_uc t = p[0]; + if (a) { + p[0] = p[2] * 255 / a; + p[1] = p[1] * 255 / a; + p[2] = t * 255 / a; + } + else { + p[0] = p[2]; + p[2] = t; + } + p += 4; + } + } + else { + // convert bgr to rgb + for (i = 0; i < pixel_count; ++i) { + stbi_uc t = p[0]; + p[0] = p[2]; + p[2] = t; + p += 4; + } + } + } +} + +#define STBI__PNG_TYPE(a,b,c,d) (((a) << 24) + ((b) << 16) + ((c) << 8) + (d)) + +static int stbi__parse_png_file(stbi__png *z, int scan, int req_comp) +{ + stbi_uc palette[1024], pal_img_n = 0; + stbi_uc has_trans = 0, tc[3]; + stbi__uint32 ioff = 0, idata_limit = 0, i, pal_len = 0; + int first = 1, k, interlace = 0, color = 0, depth = 0, is_iphone = 0; + stbi__context *s = z->s; + + z->expanded = NULL; + z->idata = NULL; + z->out = NULL; + + if (!stbi__check_png_header(s)) return 0; + + if (scan == STBI__SCAN_type) return 1; + + for (;;) { + stbi__pngchunk c = stbi__get_chunk_header(s); + switch (c.type) { + case STBI__PNG_TYPE('C', 'g', 'B', 'I'): + is_iphone = 1; + stbi__skip(s, c.length); + break; + case STBI__PNG_TYPE('I', 'H', 'D', 'R'): { + int comp, filter; + if (!first) return stbi__err("multiple IHDR", "Corrupt PNG"); + first = 0; + if (c.length != 13) return stbi__err("bad IHDR len", "Corrupt PNG"); + s->img_x = stbi__get32be(s); if (s->img_x > (1 << 24)) return stbi__err("too large", "Very large image (corrupt?)"); + s->img_y = stbi__get32be(s); if (s->img_y > (1 << 24)) return stbi__err("too large", "Very large image (corrupt?)"); + depth = stbi__get8(s); if (depth != 1 && depth != 2 && depth != 4 && depth != 8) return stbi__err("1/2/4/8-bit only", "PNG not supported: 1/2/4/8-bit only"); + color = stbi__get8(s); if (color > 6) return stbi__err("bad ctype", "Corrupt PNG"); + if (color == 3) pal_img_n = 3; else if (color & 1) return stbi__err("bad ctype", "Corrupt PNG"); + comp = stbi__get8(s); if (comp) return stbi__err("bad comp method", "Corrupt PNG"); + filter = stbi__get8(s); if (filter) return stbi__err("bad filter method", "Corrupt PNG"); + interlace = stbi__get8(s); if (interlace>1) return stbi__err("bad interlace method", "Corrupt PNG"); + if (!s->img_x || !s->img_y) return stbi__err("0-pixel image", "Corrupt PNG"); + if (!pal_img_n) { + s->img_n = (color & 2 ? 3 : 1) + (color & 4 ? 1 : 0); + if ((1 << 30) / s->img_x / s->img_n < s->img_y) return stbi__err("too large", "Image too large to decode"); + if (scan == STBI__SCAN_header) return 1; + } + else { + // if paletted, then pal_n is our final components, and + // img_n is # components to decompress/filter. + s->img_n = 1; + if ((1 << 30) / s->img_x / 4 < s->img_y) return stbi__err("too large", "Corrupt PNG"); + // if SCAN_header, have to scan to see if we have a tRNS + } + break; + } + + case STBI__PNG_TYPE('P', 'L', 'T', 'E'): { + if (first) return stbi__err("first not IHDR", "Corrupt PNG"); + if (c.length > 256 * 3) return stbi__err("invalid PLTE", "Corrupt PNG"); + pal_len = c.length / 3; + if (pal_len * 3 != c.length) return stbi__err("invalid PLTE", "Corrupt PNG"); + for (i = 0; i < pal_len; ++i) { + palette[i * 4 + 0] = stbi__get8(s); + palette[i * 4 + 1] = stbi__get8(s); + palette[i * 4 + 2] = stbi__get8(s); + palette[i * 4 + 3] = 255; + } + break; + } + + case STBI__PNG_TYPE('t', 'R', 'N', 'S'): { + if (first) return stbi__err("first not IHDR", "Corrupt PNG"); + if (z->idata) return stbi__err("tRNS after IDAT", "Corrupt PNG"); + if (pal_img_n) { + if (scan == STBI__SCAN_header) { s->img_n = 4; return 1; } + if (pal_len == 0) return stbi__err("tRNS before PLTE", "Corrupt PNG"); + if (c.length > pal_len) return stbi__err("bad tRNS len", "Corrupt PNG"); + pal_img_n = 4; + for (i = 0; i < c.length; ++i) + palette[i * 4 + 3] = stbi__get8(s); + } + else { + if (!(s->img_n & 1)) return stbi__err("tRNS with alpha", "Corrupt PNG"); + if (c.length != (stbi__uint32)s->img_n * 2) return stbi__err("bad tRNS len", "Corrupt PNG"); + has_trans = 1; + for (k = 0; k < s->img_n; ++k) + tc[k] = (stbi_uc)(stbi__get16be(s) & 255) * stbi__depth_scale_table[depth]; // non 8-bit images will be larger + } + break; + } + + case STBI__PNG_TYPE('I', 'D', 'A', 'T'): { + if (first) return stbi__err("first not IHDR", "Corrupt PNG"); + if (pal_img_n && !pal_len) return stbi__err("no PLTE", "Corrupt PNG"); + if (scan == STBI__SCAN_header) { s->img_n = pal_img_n; return 1; } + if ((int)(ioff + c.length) < (int)ioff) return 0; + if (ioff + c.length > idata_limit) { + stbi__uint32 idata_limit_old = idata_limit; + stbi_uc *p; + if (idata_limit == 0) idata_limit = c.length > 4096 ? c.length : 4096; + while (ioff + c.length > idata_limit) + idata_limit *= 2; + STBI_NOTUSED(idata_limit_old); + p = (stbi_uc *)STBI_REALLOC_SIZED(z->idata, idata_limit_old, idata_limit); if (p == NULL) return stbi__err("outofmem", "Out of memory"); + z->idata = p; + } + if (!stbi__getn(s, z->idata + ioff, c.length)) return stbi__err("outofdata", "Corrupt PNG"); + ioff += c.length; + break; + } + + case STBI__PNG_TYPE('I', 'E', 'N', 'D'): { + stbi__uint32 raw_len, bpl; + if (first) return stbi__err("first not IHDR", "Corrupt PNG"); + if (scan != STBI__SCAN_load) return 1; + if (z->idata == NULL) return stbi__err("no IDAT", "Corrupt PNG"); + // initial guess for decoded data size to avoid unnecessary reallocs + bpl = (s->img_x * depth + 7) / 8; // bytes per line, per component + raw_len = bpl * s->img_y * s->img_n /* pixels */ + s->img_y /* filter mode per row */; + z->expanded = (stbi_uc *)stbi_zlib_decode_malloc_guesssize_headerflag((char *)z->idata, ioff, raw_len, (int *)&raw_len, !is_iphone); + if (z->expanded == NULL) return 0; // zlib should set error + STBI_FREE(z->idata); z->idata = NULL; + if ((req_comp == s->img_n + 1 && req_comp != 3 && !pal_img_n) || has_trans) + s->img_out_n = s->img_n + 1; + else + s->img_out_n = s->img_n; + if (!stbi__create_png_image(z, z->expanded, raw_len, s->img_out_n, depth, color, interlace)) return 0; + if (has_trans) + if (!stbi__compute_transparency(z, tc, s->img_out_n)) return 0; + if (is_iphone && stbi__de_iphone_flag && s->img_out_n > 2) + stbi__de_iphone(z); + if (pal_img_n) { + // pal_img_n == 3 or 4 + s->img_n = pal_img_n; // record the actual colors we had + s->img_out_n = pal_img_n; + if (req_comp >= 3) s->img_out_n = req_comp; + if (!stbi__expand_png_palette(z, palette, pal_len, s->img_out_n)) + return 0; + } + STBI_FREE(z->expanded); z->expanded = NULL; + return 1; + } + + default: + // if critical, fail + if (first) return stbi__err("first not IHDR", "Corrupt PNG"); + if ((c.type & (1 << 29)) == 0) { +#ifndef STBI_NO_FAILURE_STRINGS + // not threadsafe + static char invalid_chunk[] = "XXXX PNG chunk not known"; + invalid_chunk[0] = STBI__BYTECAST(c.type >> 24); + invalid_chunk[1] = STBI__BYTECAST(c.type >> 16); + invalid_chunk[2] = STBI__BYTECAST(c.type >> 8); + invalid_chunk[3] = STBI__BYTECAST(c.type >> 0); +#endif + return stbi__err(invalid_chunk, "PNG not supported: unknown PNG chunk type"); + } + stbi__skip(s, c.length); + break; + } + // end of PNG chunk, read and skip CRC + stbi__get32be(s); + } +} + +static unsigned char *stbi__do_png(stbi__png *p, int *x, int *y, int *n, int req_comp) +{ + unsigned char *result = NULL; + if (req_comp < 0 || req_comp > 4) return stbi__errpuc("bad req_comp", "Internal error"); + if (stbi__parse_png_file(p, STBI__SCAN_load, req_comp)) { + result = p->out; + p->out = NULL; + if (req_comp && req_comp != p->s->img_out_n) { + result = stbi__convert_format(result, p->s->img_out_n, req_comp, p->s->img_x, p->s->img_y); + p->s->img_out_n = req_comp; + if (result == NULL) return result; + } + *x = p->s->img_x; + *y = p->s->img_y; + if (n) *n = p->s->img_out_n; + } + STBI_FREE(p->out); p->out = NULL; + STBI_FREE(p->expanded); p->expanded = NULL; + STBI_FREE(p->idata); p->idata = NULL; + + return result; +} + +static unsigned char *stbi__png_load(stbi__context *s, int *x, int *y, int *comp, int req_comp) +{ + stbi__png p; + p.s = s; + return stbi__do_png(&p, x, y, comp, req_comp); +} + +static int stbi__png_test(stbi__context *s) +{ + int r; + r = stbi__check_png_header(s); + stbi__rewind(s); + return r; +} + +static int stbi__png_info_raw(stbi__png *p, int *x, int *y, int *comp) +{ + if (!stbi__parse_png_file(p, STBI__SCAN_header, 0)) { + stbi__rewind(p->s); + return 0; + } + if (x) *x = p->s->img_x; + if (y) *y = p->s->img_y; + if (comp) *comp = p->s->img_n; + return 1; +} + +static int stbi__png_info(stbi__context *s, int *x, int *y, int *comp) +{ + stbi__png p; + p.s = s; + return stbi__png_info_raw(&p, x, y, comp); +} +#endif + +// Microsoft/Windows BMP image + +#ifndef STBI_NO_BMP +static int stbi__bmp_test_raw(stbi__context *s) +{ + int r; + int sz; + if (stbi__get8(s) != 'B') return 0; + if (stbi__get8(s) != 'M') return 0; + stbi__get32le(s); // discard filesize + stbi__get16le(s); // discard reserved + stbi__get16le(s); // discard reserved + stbi__get32le(s); // discard data offset + sz = stbi__get32le(s); + r = (sz == 12 || sz == 40 || sz == 56 || sz == 108 || sz == 124); + return r; +} + +static int stbi__bmp_test(stbi__context *s) +{ + int r = stbi__bmp_test_raw(s); + stbi__rewind(s); + return r; +} + + +// returns 0..31 for the highest set bit +static int stbi__high_bit(unsigned int z) +{ + int n = 0; + if (z == 0) return -1; + if (z >= 0x10000) n += 16, z >>= 16; + if (z >= 0x00100) n += 8, z >>= 8; + if (z >= 0x00010) n += 4, z >>= 4; + if (z >= 0x00004) n += 2, z >>= 2; + if (z >= 0x00002) n += 1, z >>= 1; + return n; +} + +static int stbi__bitcount(unsigned int a) +{ + a = (a & 0x55555555) + ((a >> 1) & 0x55555555); // max 2 + a = (a & 0x33333333) + ((a >> 2) & 0x33333333); // max 4 + a = (a + (a >> 4)) & 0x0f0f0f0f; // max 8 per 4, now 8 bits + a = (a + (a >> 8)); // max 16 per 8 bits + a = (a + (a >> 16)); // max 32 per 8 bits + return a & 0xff; +} + +static int stbi__shiftsigned(int v, int shift, int bits) +{ + int result; + int z = 0; + + if (shift < 0) v <<= -shift; + else v >>= shift; + result = v; + + z = bits; + while (z < 8) { + result += v >> z; + z += bits; + } + return result; +} + +typedef struct +{ + int bpp, offset, hsz; + unsigned int mr, mg, mb, ma, all_a; +} stbi__bmp_data; + +static void *stbi__bmp_parse_header(stbi__context *s, stbi__bmp_data *info) +{ + int hsz; + if (stbi__get8(s) != 'B' || stbi__get8(s) != 'M') return stbi__errpuc("not BMP", "Corrupt BMP"); + stbi__get32le(s); // discard filesize + stbi__get16le(s); // discard reserved + stbi__get16le(s); // discard reserved + info->offset = stbi__get32le(s); + info->hsz = hsz = stbi__get32le(s); + + if (hsz != 12 && hsz != 40 && hsz != 56 && hsz != 108 && hsz != 124) return stbi__errpuc("unknown BMP", "BMP type not supported: unknown"); + if (hsz == 12) { + s->img_x = stbi__get16le(s); + s->img_y = stbi__get16le(s); + } + else { + s->img_x = stbi__get32le(s); + s->img_y = stbi__get32le(s); + } + if (stbi__get16le(s) != 1) return stbi__errpuc("bad BMP", "bad BMP"); + info->bpp = stbi__get16le(s); + if (info->bpp == 1) return stbi__errpuc("monochrome", "BMP type not supported: 1-bit"); + if (hsz != 12) { + int compress = stbi__get32le(s); + if (compress == 1 || compress == 2) return stbi__errpuc("BMP RLE", "BMP type not supported: RLE"); + stbi__get32le(s); // discard sizeof + stbi__get32le(s); // discard hres + stbi__get32le(s); // discard vres + stbi__get32le(s); // discard colorsused + stbi__get32le(s); // discard max important + if (hsz == 40 || hsz == 56) { + if (hsz == 56) { + stbi__get32le(s); + stbi__get32le(s); + stbi__get32le(s); + stbi__get32le(s); + } + if (info->bpp == 16 || info->bpp == 32) { + info->mr = info->mg = info->mb = 0; + if (compress == 0) { + if (info->bpp == 32) { + info->mr = 0xffu << 16; + info->mg = 0xffu << 8; + info->mb = 0xffu << 0; + info->ma = 0xffu << 24; + info->all_a = 0; // if all_a is 0 at end, then we loaded alpha channel but it was all 0 + } + else { + info->mr = 31u << 10; + info->mg = 31u << 5; + info->mb = 31u << 0; + } + } + else if (compress == 3) { + info->mr = stbi__get32le(s); + info->mg = stbi__get32le(s); + info->mb = stbi__get32le(s); + // not documented, but generated by photoshop and handled by mspaint + if (info->mr == info->mg && info->mg == info->mb) { + // ?!?!? + return stbi__errpuc("bad BMP", "bad BMP"); + } + } + else + return stbi__errpuc("bad BMP", "bad BMP"); + } + } + else { + int i; + if (hsz != 108 && hsz != 124) + return stbi__errpuc("bad BMP", "bad BMP"); + info->mr = stbi__get32le(s); + info->mg = stbi__get32le(s); + info->mb = stbi__get32le(s); + info->ma = stbi__get32le(s); + stbi__get32le(s); // discard color space + for (i = 0; i < 12; ++i) + stbi__get32le(s); // discard color space parameters + if (hsz == 124) { + stbi__get32le(s); // discard rendering intent + stbi__get32le(s); // discard offset of profile data + stbi__get32le(s); // discard size of profile data + stbi__get32le(s); // discard reserved + } + } + } + return (void *)1; +} + + +static stbi_uc *stbi__bmp_load(stbi__context *s, int *x, int *y, int *comp, int req_comp) +{ + stbi_uc *out; + unsigned int mr = 0, mg = 0, mb = 0, ma = 0, all_a; + stbi_uc pal[256][4]; + int psize = 0, i, j, width; + int flip_vertically, pad, target; + stbi__bmp_data info; + + info.all_a = 255; + if (stbi__bmp_parse_header(s, &info) == NULL) + return NULL; // error code already set + + flip_vertically = ((int)s->img_y) > 0; + s->img_y = abs((int)s->img_y); + + mr = info.mr; + mg = info.mg; + mb = info.mb; + ma = info.ma; + all_a = info.all_a; + + if (info.hsz == 12) { + if (info.bpp < 24) + psize = (info.offset - 14 - 24) / 3; + } + else { + if (info.bpp < 16) + psize = (info.offset - 14 - info.hsz) >> 2; + } + + s->img_n = ma ? 4 : 3; + if (req_comp && req_comp >= 3) // we can directly decode 3 or 4 + target = req_comp; + else + target = s->img_n; // if they want monochrome, we'll post-convert + + out = (stbi_uc *)stbi__malloc(target * s->img_x * s->img_y); + if (!out) return stbi__errpuc("outofmem", "Out of memory"); + if (info.bpp < 16) { + int z = 0; + if (psize == 0 || psize > 256) { STBI_FREE(out); return stbi__errpuc("invalid", "Corrupt BMP"); } + for (i = 0; i < psize; ++i) { + pal[i][2] = stbi__get8(s); + pal[i][1] = stbi__get8(s); + pal[i][0] = stbi__get8(s); + if (info.hsz != 12) stbi__get8(s); + pal[i][3] = 255; + } + stbi__skip(s, info.offset - 14 - info.hsz - psize * (info.hsz == 12 ? 3 : 4)); + if (info.bpp == 4) width = (s->img_x + 1) >> 1; + else if (info.bpp == 8) width = s->img_x; + else { STBI_FREE(out); return stbi__errpuc("bad bpp", "Corrupt BMP"); } + pad = (-width) & 3; + for (j = 0; j < (int)s->img_y; ++j) { + for (i = 0; i < (int)s->img_x; i += 2) { + int v = stbi__get8(s), v2 = 0; + if (info.bpp == 4) { + v2 = v & 15; + v >>= 4; + } + out[z++] = pal[v][0]; + out[z++] = pal[v][1]; + out[z++] = pal[v][2]; + if (target == 4) out[z++] = 255; + if (i + 1 == (int)s->img_x) break; + v = (info.bpp == 8) ? stbi__get8(s) : v2; + out[z++] = pal[v][0]; + out[z++] = pal[v][1]; + out[z++] = pal[v][2]; + if (target == 4) out[z++] = 255; + } + stbi__skip(s, pad); + } + } + else { + int rshift = 0, gshift = 0, bshift = 0, ashift = 0, rcount = 0, gcount = 0, bcount = 0, acount = 0; + int z = 0; + int easy = 0; + stbi__skip(s, info.offset - 14 - info.hsz); + if (info.bpp == 24) width = 3 * s->img_x; + else if (info.bpp == 16) width = 2 * s->img_x; + else /* bpp = 32 and pad = 0 */ width = 0; + pad = (-width) & 3; + if (info.bpp == 24) { + easy = 1; + } + else if (info.bpp == 32) { + if (mb == 0xff && mg == 0xff00 && mr == 0x00ff0000 && ma == 0xff000000) + easy = 2; + } + if (!easy) { + if (!mr || !mg || !mb) { STBI_FREE(out); return stbi__errpuc("bad masks", "Corrupt BMP"); } + // right shift amt to put high bit in position #7 + rshift = stbi__high_bit(mr) - 7; rcount = stbi__bitcount(mr); + gshift = stbi__high_bit(mg) - 7; gcount = stbi__bitcount(mg); + bshift = stbi__high_bit(mb) - 7; bcount = stbi__bitcount(mb); + ashift = stbi__high_bit(ma) - 7; acount = stbi__bitcount(ma); + } + for (j = 0; j < (int)s->img_y; ++j) { + if (easy) { + for (i = 0; i < (int)s->img_x; ++i) { + unsigned char a; + out[z + 2] = stbi__get8(s); + out[z + 1] = stbi__get8(s); + out[z + 0] = stbi__get8(s); + z += 3; + a = (easy == 2 ? stbi__get8(s) : 255); + all_a |= a; + if (target == 4) out[z++] = a; + } + } + else { + int bpp = info.bpp; + for (i = 0; i < (int)s->img_x; ++i) { + stbi__uint32 v = (bpp == 16 ? (stbi__uint32)stbi__get16le(s) : stbi__get32le(s)); + int a; + out[z++] = STBI__BYTECAST(stbi__shiftsigned(v & mr, rshift, rcount)); + out[z++] = STBI__BYTECAST(stbi__shiftsigned(v & mg, gshift, gcount)); + out[z++] = STBI__BYTECAST(stbi__shiftsigned(v & mb, bshift, bcount)); + a = (ma ? stbi__shiftsigned(v & ma, ashift, acount) : 255); + all_a |= a; + if (target == 4) out[z++] = STBI__BYTECAST(a); + } + } + stbi__skip(s, pad); + } + } + + // if alpha channel is all 0s, replace with all 255s + if (target == 4 && all_a == 0) + for (i = 4 * s->img_x*s->img_y - 1; i >= 0; i -= 4) + out[i] = 255; + + if (flip_vertically) { + stbi_uc t; + for (j = 0; j < (int)s->img_y >> 1; ++j) { + stbi_uc *p1 = out + j *s->img_x*target; + stbi_uc *p2 = out + (s->img_y - 1 - j)*s->img_x*target; + for (i = 0; i < (int)s->img_x*target; ++i) { + t = p1[i], p1[i] = p2[i], p2[i] = t; + } + } + } + + if (req_comp && req_comp != target) { + out = stbi__convert_format(out, target, req_comp, s->img_x, s->img_y); + if (out == NULL) return out; // stbi__convert_format frees input on failure + } + + *x = s->img_x; + *y = s->img_y; + if (comp) *comp = s->img_n; + return out; +} +#endif + +// Targa Truevision - TGA +// by Jonathan Dummer +#ifndef STBI_NO_TGA +// returns STBI_rgb or whatever, 0 on error +static int stbi__tga_get_comp(int bits_per_pixel, int is_grey, int* is_rgb16) +{ + // only RGB or RGBA (incl. 16bit) or grey allowed + if (is_rgb16) *is_rgb16 = 0; + switch (bits_per_pixel) { + case 8: return STBI_grey; + case 16: if (is_grey) return STBI_grey_alpha; + // else: fall-through + case 15: if (is_rgb16) *is_rgb16 = 1; + return STBI_rgb; + case 24: // fall-through + case 32: return bits_per_pixel / 8; + default: return 0; + } +} + +static int stbi__tga_info(stbi__context *s, int *x, int *y, int *comp) +{ + int tga_w, tga_h, tga_comp, tga_image_type, tga_bits_per_pixel, tga_colormap_bpp; + int sz, tga_colormap_type; + stbi__get8(s); // discard Offset + tga_colormap_type = stbi__get8(s); // colormap type + if (tga_colormap_type > 1) { + stbi__rewind(s); + return 0; // only RGB or indexed allowed + } + tga_image_type = stbi__get8(s); // image type + if (tga_colormap_type == 1) { // colormapped (paletted) image + if (tga_image_type != 1 && tga_image_type != 9) { + stbi__rewind(s); + return 0; + } + stbi__skip(s, 4); // skip index of first colormap entry and number of entries + sz = stbi__get8(s); // check bits per palette color entry + if ((sz != 8) && (sz != 15) && (sz != 16) && (sz != 24) && (sz != 32)) { + stbi__rewind(s); + return 0; + } + stbi__skip(s, 4); // skip image x and y origin + tga_colormap_bpp = sz; + } + else { // "normal" image w/o colormap - only RGB or grey allowed, +/- RLE + if ((tga_image_type != 2) && (tga_image_type != 3) && (tga_image_type != 10) && (tga_image_type != 11)) { + stbi__rewind(s); + return 0; // only RGB or grey allowed, +/- RLE + } + stbi__skip(s, 9); // skip colormap specification and image x/y origin + tga_colormap_bpp = 0; + } + tga_w = stbi__get16le(s); + if (tga_w < 1) { + stbi__rewind(s); + return 0; // test width + } + tga_h = stbi__get16le(s); + if (tga_h < 1) { + stbi__rewind(s); + return 0; // test height + } + tga_bits_per_pixel = stbi__get8(s); // bits per pixel + stbi__get8(s); // ignore alpha bits + if (tga_colormap_bpp != 0) { + if ((tga_bits_per_pixel != 8) && (tga_bits_per_pixel != 16)) { + // when using a colormap, tga_bits_per_pixel is the size of the indexes + // I don't think anything but 8 or 16bit indexes makes sense + stbi__rewind(s); + return 0; + } + tga_comp = stbi__tga_get_comp(tga_colormap_bpp, 0, NULL); + } + else { + tga_comp = stbi__tga_get_comp(tga_bits_per_pixel, (tga_image_type == 3) || (tga_image_type == 11), NULL); + } + if (!tga_comp) { + stbi__rewind(s); + return 0; + } + if (x) *x = tga_w; + if (y) *y = tga_h; + if (comp) *comp = tga_comp; + return 1; // seems to have passed everything +} + +static int stbi__tga_test(stbi__context *s) +{ + int res = 0; + int sz, tga_color_type; + stbi__get8(s); // discard Offset + tga_color_type = stbi__get8(s); // color type + if (tga_color_type > 1) goto errorEnd; // only RGB or indexed allowed + sz = stbi__get8(s); // image type + if (tga_color_type == 1) { // colormapped (paletted) image + if (sz != 1 && sz != 9) goto errorEnd; // colortype 1 demands image type 1 or 9 + stbi__skip(s, 4); // skip index of first colormap entry and number of entries + sz = stbi__get8(s); // check bits per palette color entry + if ((sz != 8) && (sz != 15) && (sz != 16) && (sz != 24) && (sz != 32)) goto errorEnd; + stbi__skip(s, 4); // skip image x and y origin + } + else { // "normal" image w/o colormap + if ((sz != 2) && (sz != 3) && (sz != 10) && (sz != 11)) goto errorEnd; // only RGB or grey allowed, +/- RLE + stbi__skip(s, 9); // skip colormap specification and image x/y origin + } + if (stbi__get16le(s) < 1) goto errorEnd; // test width + if (stbi__get16le(s) < 1) goto errorEnd; // test height + sz = stbi__get8(s); // bits per pixel + if ((tga_color_type == 1) && (sz != 8) && (sz != 16)) goto errorEnd; // for colormapped images, bpp is size of an index + if ((sz != 8) && (sz != 15) && (sz != 16) && (sz != 24) && (sz != 32)) goto errorEnd; + + res = 1; // if we got this far, everything's good and we can return 1 instead of 0 + +errorEnd: + stbi__rewind(s); + return res; +} + +// read 16bit value and convert to 24bit RGB +void stbi__tga_read_rgb16(stbi__context *s, stbi_uc* out) +{ + stbi__uint16 px = stbi__get16le(s); + stbi__uint16 fiveBitMask = 31; + // we have 3 channels with 5bits each + int r = (px >> 10) & fiveBitMask; + int g = (px >> 5) & fiveBitMask; + int b = px & fiveBitMask; + // Note that this saves the data in RGB(A) order, so it doesn't need to be swapped later + out[0] = (r * 255) / 31; + out[1] = (g * 255) / 31; + out[2] = (b * 255) / 31; + + // some people claim that the most significant bit might be used for alpha + // (possibly if an alpha-bit is set in the "image descriptor byte") + // but that only made 16bit test images completely translucent.. + // so let's treat all 15 and 16bit TGAs as RGB with no alpha. +} + +static stbi_uc *stbi__tga_load(stbi__context *s, int *x, int *y, int *comp, int req_comp) +{ + // read in the TGA header stuff + int tga_offset = stbi__get8(s); + int tga_indexed = stbi__get8(s); + int tga_image_type = stbi__get8(s); + int tga_is_RLE = 0; + int tga_palette_start = stbi__get16le(s); + int tga_palette_len = stbi__get16le(s); + int tga_palette_bits = stbi__get8(s); + int tga_x_origin = stbi__get16le(s); + int tga_y_origin = stbi__get16le(s); + int tga_width = stbi__get16le(s); + int tga_height = stbi__get16le(s); + int tga_bits_per_pixel = stbi__get8(s); + int tga_comp, tga_rgb16 = 0; + int tga_inverted = stbi__get8(s); + // int tga_alpha_bits = tga_inverted & 15; // the 4 lowest bits - unused (useless?) + // image data + unsigned char *tga_data; + unsigned char *tga_palette = NULL; + int i, j; + unsigned char raw_data[4]; + int RLE_count = 0; + int RLE_repeating = 0; + int read_next_pixel = 1; + + // do a tiny bit of precessing + if (tga_image_type >= 8) + { + tga_image_type -= 8; + tga_is_RLE = 1; + } + tga_inverted = 1 - ((tga_inverted >> 5) & 1); + + // If I'm paletted, then I'll use the number of bits from the palette + if (tga_indexed) tga_comp = stbi__tga_get_comp(tga_palette_bits, 0, &tga_rgb16); + else tga_comp = stbi__tga_get_comp(tga_bits_per_pixel, (tga_image_type == 3), &tga_rgb16); + + if (!tga_comp) // shouldn't really happen, stbi__tga_test() should have ensured basic consistency + return stbi__errpuc("bad format", "Can't find out TGA pixelformat"); + + // tga info + *x = tga_width; + *y = tga_height; + if (comp) *comp = tga_comp; + + tga_data = (unsigned char*)stbi__malloc((size_t)tga_width * tga_height * tga_comp); + if (!tga_data) return stbi__errpuc("outofmem", "Out of memory"); + + // skip to the data's starting position (offset usually = 0) + stbi__skip(s, tga_offset); + + if (!tga_indexed && !tga_is_RLE && !tga_rgb16) { + for (i = 0; i < tga_height; ++i) { + int row = tga_inverted ? tga_height - i - 1 : i; + stbi_uc *tga_row = tga_data + row*tga_width*tga_comp; + stbi__getn(s, tga_row, tga_width * tga_comp); + } + } + else { + // do I need to load a palette? + if (tga_indexed) + { + // any data to skip? (offset usually = 0) + stbi__skip(s, tga_palette_start); + // load the palette + tga_palette = (unsigned char*)stbi__malloc(tga_palette_len * tga_comp); + if (!tga_palette) { + STBI_FREE(tga_data); + return stbi__errpuc("outofmem", "Out of memory"); + } + if (tga_rgb16) { + stbi_uc *pal_entry = tga_palette; + STBI_ASSERT(tga_comp == STBI_rgb); + for (i = 0; i < tga_palette_len; ++i) { + stbi__tga_read_rgb16(s, pal_entry); + pal_entry += tga_comp; + } + } + else if (!stbi__getn(s, tga_palette, tga_palette_len * tga_comp)) { + STBI_FREE(tga_data); + STBI_FREE(tga_palette); + return stbi__errpuc("bad palette", "Corrupt TGA"); + } + } + // load the data + for (i = 0; i < tga_width * tga_height; ++i) + { + // if I'm in RLE mode, do I need to get a RLE stbi__pngchunk? + if (tga_is_RLE) + { + if (RLE_count == 0) + { + // yep, get the next byte as a RLE command + int RLE_cmd = stbi__get8(s); + RLE_count = 1 + (RLE_cmd & 127); + RLE_repeating = RLE_cmd >> 7; + read_next_pixel = 1; + } + else if (!RLE_repeating) + { + read_next_pixel = 1; + } + } + else + { + read_next_pixel = 1; + } + // OK, if I need to read a pixel, do it now + if (read_next_pixel) + { + // load however much data we did have + if (tga_indexed) + { + // read in index, then perform the lookup + int pal_idx = (tga_bits_per_pixel == 8) ? stbi__get8(s) : stbi__get16le(s); + if (pal_idx >= tga_palette_len) { + // invalid index + pal_idx = 0; + } + pal_idx *= tga_comp; + for (j = 0; j < tga_comp; ++j) { + raw_data[j] = tga_palette[pal_idx + j]; + } + } + else if (tga_rgb16) { + STBI_ASSERT(tga_comp == STBI_rgb); + stbi__tga_read_rgb16(s, raw_data); + } + else { + // read in the data raw + for (j = 0; j < tga_comp; ++j) { + raw_data[j] = stbi__get8(s); + } + } + // clear the reading flag for the next pixel + read_next_pixel = 0; + } // end of reading a pixel + + // copy data + for (j = 0; j < tga_comp; ++j) + tga_data[i*tga_comp + j] = raw_data[j]; + + // in case we're in RLE mode, keep counting down + --RLE_count; + } + // do I need to invert the image? + if (tga_inverted) + { + for (j = 0; j * 2 < tga_height; ++j) + { + int index1 = j * tga_width * tga_comp; + int index2 = (tga_height - 1 - j) * tga_width * tga_comp; + for (i = tga_width * tga_comp; i > 0; --i) + { + unsigned char temp = tga_data[index1]; + tga_data[index1] = tga_data[index2]; + tga_data[index2] = temp; + ++index1; + ++index2; + } + } + } + // clear my palette, if I had one + if (tga_palette != NULL) + { + STBI_FREE(tga_palette); + } + } + + // swap RGB - if the source data was RGB16, it already is in the right order + if (tga_comp >= 3 && !tga_rgb16) + { + unsigned char* tga_pixel = tga_data; + for (i = 0; i < tga_width * tga_height; ++i) + { + unsigned char temp = tga_pixel[0]; + tga_pixel[0] = tga_pixel[2]; + tga_pixel[2] = temp; + tga_pixel += tga_comp; + } + } + + // convert to target component count + if (req_comp && req_comp != tga_comp) + tga_data = stbi__convert_format(tga_data, tga_comp, req_comp, tga_width, tga_height); + + // the things I do to get rid of an error message, and yet keep + // Microsoft's C compilers happy... [8^( + tga_palette_start = tga_palette_len = tga_palette_bits = + tga_x_origin = tga_y_origin = 0; + // OK, done + return tga_data; +} +#endif + +// ************************************************************************************************* +// Photoshop PSD loader -- PD by Thatcher Ulrich, integration by Nicolas Schulz, tweaked by STB + +#ifndef STBI_NO_PSD +static int stbi__psd_test(stbi__context *s) +{ + int r = (stbi__get32be(s) == 0x38425053); + stbi__rewind(s); + return r; +} + +static stbi_uc *stbi__psd_load(stbi__context *s, int *x, int *y, int *comp, int req_comp) +{ + int pixelCount; + int channelCount, compression; + int channel, i, count, len; + int bitdepth; + int w, h; + stbi_uc *out; + + // Check identifier + if (stbi__get32be(s) != 0x38425053) // "8BPS" + return stbi__errpuc("not PSD", "Corrupt PSD image"); + + // Check file type version. + if (stbi__get16be(s) != 1) + return stbi__errpuc("wrong version", "Unsupported version of PSD image"); + + // Skip 6 reserved bytes. + stbi__skip(s, 6); + + // Read the number of channels (R, G, B, A, etc). + channelCount = stbi__get16be(s); + if (channelCount < 0 || channelCount > 16) + return stbi__errpuc("wrong channel count", "Unsupported number of channels in PSD image"); + + // Read the rows and columns of the image. + h = stbi__get32be(s); + w = stbi__get32be(s); + + // Make sure the depth is 8 bits. + bitdepth = stbi__get16be(s); + if (bitdepth != 8 && bitdepth != 16) + return stbi__errpuc("unsupported bit depth", "PSD bit depth is not 8 or 16 bit"); + + // Make sure the color mode is RGB. + // Valid options are: + // 0: Bitmap + // 1: Grayscale + // 2: Indexed color + // 3: RGB color + // 4: CMYK color + // 7: Multichannel + // 8: Duotone + // 9: Lab color + if (stbi__get16be(s) != 3) + return stbi__errpuc("wrong color format", "PSD is not in RGB color format"); + + // Skip the Mode Data. (It's the palette for indexed color; other info for other modes.) + stbi__skip(s, stbi__get32be(s)); + + // Skip the image resources. (resolution, pen tool paths, etc) + stbi__skip(s, stbi__get32be(s)); + + // Skip the reserved data. + stbi__skip(s, stbi__get32be(s)); + + // Find out if the data is compressed. + // Known values: + // 0: no compression + // 1: RLE compressed + compression = stbi__get16be(s); + if (compression > 1) + return stbi__errpuc("bad compression", "PSD has an unknown compression format"); + + // Create the destination image. + out = (stbi_uc *)stbi__malloc(4 * w*h); + if (!out) return stbi__errpuc("outofmem", "Out of memory"); + pixelCount = w*h; + + // Initialize the data to zero. + //memset( out, 0, pixelCount * 4 ); + + // Finally, the image data. + if (compression) { + // RLE as used by .PSD and .TIFF + // Loop until you get the number of unpacked bytes you are expecting: + // Read the next source byte into n. + // If n is between 0 and 127 inclusive, copy the next n+1 bytes literally. + // Else if n is between -127 and -1 inclusive, copy the next byte -n+1 times. + // Else if n is 128, noop. + // Endloop + + // The RLE-compressed data is preceeded by a 2-byte data count for each row in the data, + // which we're going to just skip. + stbi__skip(s, h * channelCount * 2); + + // Read the RLE data by channel. + for (channel = 0; channel < 4; channel++) { + stbi_uc *p; + + p = out + channel; + if (channel >= channelCount) { + // Fill this channel with default data. + for (i = 0; i < pixelCount; i++, p += 4) + *p = (channel == 3 ? 255 : 0); + } + else { + // Read the RLE data. + count = 0; + while (count < pixelCount) { + len = stbi__get8(s); + if (len == 128) { + // No-op. + } + else if (len < 128) { + // Copy next len+1 bytes literally. + len++; + count += len; + while (len) { + *p = stbi__get8(s); + p += 4; + len--; + } + } + else if (len > 128) { + stbi_uc val; + // Next -len+1 bytes in the dest are replicated from next source byte. + // (Interpret len as a negative 8-bit int.) + len ^= 0x0FF; + len += 2; + val = stbi__get8(s); + count += len; + while (len) { + *p = val; + p += 4; + len--; + } + } + } + } + } + + } + else { + // We're at the raw image data. It's each channel in order (Red, Green, Blue, Alpha, ...) + // where each channel consists of an 8-bit value for each pixel in the image. + + // Read the data by channel. + for (channel = 0; channel < 4; channel++) { + stbi_uc *p; + + p = out + channel; + if (channel >= channelCount) { + // Fill this channel with default data. + stbi_uc val = channel == 3 ? 255 : 0; + for (i = 0; i < pixelCount; i++, p += 4) + *p = val; + } + else { + // Read the data. + if (bitdepth == 16) { + for (i = 0; i < pixelCount; i++, p += 4) + *p = (stbi_uc)(stbi__get16be(s) >> 8); + } + else { + for (i = 0; i < pixelCount; i++, p += 4) + *p = stbi__get8(s); + } + } + } + } + + if (req_comp && req_comp != 4) { + out = stbi__convert_format(out, 4, req_comp, w, h); + if (out == NULL) return out; // stbi__convert_format frees input on failure + } + + if (comp) *comp = 4; + *y = h; + *x = w; + + return out; +} +#endif + +// ************************************************************************************************* +// Softimage PIC loader +// by Tom Seddon +// +// See http://softimage.wiki.softimage.com/index.php/INFO:_PIC_file_format +// See http://ozviz.wasp.uwa.edu.au/~pbourke/dataformats/softimagepic/ + +#ifndef STBI_NO_PIC +static int stbi__pic_is4(stbi__context *s, const char *str) +{ + int i; + for (i = 0; i<4; ++i) + if (stbi__get8(s) != (stbi_uc)str[i]) + return 0; + + return 1; +} + +static int stbi__pic_test_core(stbi__context *s) +{ + int i; + + if (!stbi__pic_is4(s, "\x53\x80\xF6\x34")) + return 0; + + for (i = 0; i<84; ++i) + stbi__get8(s); + + if (!stbi__pic_is4(s, "PICT")) + return 0; + + return 1; +} + +typedef struct +{ + stbi_uc size, type, channel; +} stbi__pic_packet; + +static stbi_uc *stbi__readval(stbi__context *s, int channel, stbi_uc *dest) +{ + int mask = 0x80, i; + + for (i = 0; i<4; ++i, mask >>= 1) { + if (channel & mask) { + if (stbi__at_eof(s)) return stbi__errpuc("bad file", "PIC file too short"); + dest[i] = stbi__get8(s); + } + } + + return dest; +} + +static void stbi__copyval(int channel, stbi_uc *dest, const stbi_uc *src) +{ + int mask = 0x80, i; + + for (i = 0; i<4; ++i, mask >>= 1) + if (channel&mask) + dest[i] = src[i]; +} + +static stbi_uc *stbi__pic_load_core(stbi__context *s, int width, int height, int *comp, stbi_uc *result) +{ + int act_comp = 0, num_packets = 0, y, chained; + stbi__pic_packet packets[10]; + + // this will (should...) cater for even some bizarre stuff like having data + // for the same channel in multiple packets. + do { + stbi__pic_packet *packet; + + if (num_packets == sizeof(packets) / sizeof(packets[0])) + return stbi__errpuc("bad format", "too many packets"); + + packet = &packets[num_packets++]; + + chained = stbi__get8(s); + packet->size = stbi__get8(s); + packet->type = stbi__get8(s); + packet->channel = stbi__get8(s); + + act_comp |= packet->channel; + + if (stbi__at_eof(s)) return stbi__errpuc("bad file", "file too short (reading packets)"); + if (packet->size != 8) return stbi__errpuc("bad format", "packet isn't 8bpp"); + } while (chained); + + *comp = (act_comp & 0x10 ? 4 : 3); // has alpha channel? + + for (y = 0; ytype) { + default: + return stbi__errpuc("bad format", "packet has bad compression type"); + + case 0: {//uncompressed + int x; + + for (x = 0; xchannel, dest)) + return 0; + break; + } + + case 1://Pure RLE + { + int left = width, i; + + while (left>0) { + stbi_uc count, value[4]; + + count = stbi__get8(s); + if (stbi__at_eof(s)) return stbi__errpuc("bad file", "file too short (pure read count)"); + + if (count > left) + count = (stbi_uc)left; + + if (!stbi__readval(s, packet->channel, value)) return 0; + + for (i = 0; ichannel, dest, value); + left -= count; + } + } + break; + + case 2: {//Mixed RLE + int left = width; + while (left>0) { + int count = stbi__get8(s), i; + if (stbi__at_eof(s)) return stbi__errpuc("bad file", "file too short (mixed read count)"); + + if (count >= 128) { // Repeated + stbi_uc value[4]; + + if (count == 128) + count = stbi__get16be(s); + else + count -= 127; + if (count > left) + return stbi__errpuc("bad file", "scanline overrun"); + + if (!stbi__readval(s, packet->channel, value)) + return 0; + + for (i = 0; ichannel, dest, value); + } + else { // Raw + ++count; + if (count>left) return stbi__errpuc("bad file", "scanline overrun"); + + for (i = 0; ichannel, dest)) + return 0; + } + left -= count; + } + break; + } + } + } + } + + return result; +} + +static stbi_uc *stbi__pic_load(stbi__context *s, int *px, int *py, int *comp, int req_comp) +{ + stbi_uc *result; + int i, x, y; + + for (i = 0; i<92; ++i) + stbi__get8(s); + + x = stbi__get16be(s); + y = stbi__get16be(s); + if (stbi__at_eof(s)) return stbi__errpuc("bad file", "file too short (pic header)"); + if ((1 << 28) / x < y) return stbi__errpuc("too large", "Image too large to decode"); + + stbi__get32be(s); //skip `ratio' + stbi__get16be(s); //skip `fields' + stbi__get16be(s); //skip `pad' + + // intermediate buffer is RGBA + result = (stbi_uc *)stbi__malloc(x*y * 4); + memset(result, 0xff, x*y * 4); + + if (!stbi__pic_load_core(s, x, y, comp, result)) { + STBI_FREE(result); + result = 0; + } + *px = x; + *py = y; + if (req_comp == 0) req_comp = *comp; + result = stbi__convert_format(result, 4, req_comp, x, y); + + return result; +} + +static int stbi__pic_test(stbi__context *s) +{ + int r = stbi__pic_test_core(s); + stbi__rewind(s); + return r; +} +#endif + +// ************************************************************************************************* +// GIF loader -- public domain by Jean-Marc Lienher -- simplified/shrunk by stb + +#ifndef STBI_NO_GIF +typedef struct +{ + stbi__int16 prefix; + stbi_uc first; + stbi_uc suffix; +} stbi__gif_lzw; + +typedef struct +{ + int w, h; + stbi_uc *out, *old_out; // output buffer (always 4 components) + int flags, bgindex, ratio, transparent, eflags, delay; + stbi_uc pal[256][4]; + stbi_uc lpal[256][4]; + stbi__gif_lzw codes[4096]; + stbi_uc *color_table; + int parse, step; + int lflags; + int start_x, start_y; + int max_x, max_y; + int cur_x, cur_y; + int line_size; +} stbi__gif; + +static int stbi__gif_test_raw(stbi__context *s) +{ + int sz; + if (stbi__get8(s) != 'G' || stbi__get8(s) != 'I' || stbi__get8(s) != 'F' || stbi__get8(s) != '8') return 0; + sz = stbi__get8(s); + if (sz != '9' && sz != '7') return 0; + if (stbi__get8(s) != 'a') return 0; + return 1; +} + +static int stbi__gif_test(stbi__context *s) +{ + int r = stbi__gif_test_raw(s); + stbi__rewind(s); + return r; +} + +static void stbi__gif_parse_colortable(stbi__context *s, stbi_uc pal[256][4], int num_entries, int transp) +{ + int i; + for (i = 0; i < num_entries; ++i) { + pal[i][2] = stbi__get8(s); + pal[i][1] = stbi__get8(s); + pal[i][0] = stbi__get8(s); + pal[i][3] = transp == i ? 0 : 255; + } +} + +static int stbi__gif_header(stbi__context *s, stbi__gif *g, int *comp, int is_info) +{ + stbi_uc version; + if (stbi__get8(s) != 'G' || stbi__get8(s) != 'I' || stbi__get8(s) != 'F' || stbi__get8(s) != '8') + return stbi__err("not GIF", "Corrupt GIF"); + + version = stbi__get8(s); + if (version != '7' && version != '9') return stbi__err("not GIF", "Corrupt GIF"); + if (stbi__get8(s) != 'a') return stbi__err("not GIF", "Corrupt GIF"); + + stbi__g_failure_reason = ""; + g->w = stbi__get16le(s); + g->h = stbi__get16le(s); + g->flags = stbi__get8(s); + g->bgindex = stbi__get8(s); + g->ratio = stbi__get8(s); + g->transparent = -1; + + if (comp != 0) *comp = 4; // can't actually tell whether it's 3 or 4 until we parse the comments + + if (is_info) return 1; + + if (g->flags & 0x80) + stbi__gif_parse_colortable(s, g->pal, 2 << (g->flags & 7), -1); + + return 1; +} + +static int stbi__gif_info_raw(stbi__context *s, int *x, int *y, int *comp) +{ + stbi__gif g; + if (!stbi__gif_header(s, &g, comp, 1)) { + stbi__rewind(s); + return 0; + } + if (x) *x = g.w; + if (y) *y = g.h; + return 1; +} + +static void stbi__out_gif_code(stbi__gif *g, stbi__uint16 code) +{ + stbi_uc *p, *c; + + // recurse to decode the prefixes, since the linked-list is backwards, + // and working backwards through an interleaved image would be nasty + if (g->codes[code].prefix >= 0) + stbi__out_gif_code(g, g->codes[code].prefix); + + if (g->cur_y >= g->max_y) return; + + p = &g->out[g->cur_x + g->cur_y]; + c = &g->color_table[g->codes[code].suffix * 4]; + + if (c[3] >= 128) { + p[0] = c[2]; + p[1] = c[1]; + p[2] = c[0]; + p[3] = c[3]; + } + g->cur_x += 4; + + if (g->cur_x >= g->max_x) { + g->cur_x = g->start_x; + g->cur_y += g->step; + + while (g->cur_y >= g->max_y && g->parse > 0) { + g->step = (1 << g->parse) * g->line_size; + g->cur_y = g->start_y + (g->step >> 1); + --g->parse; + } + } +} + +static stbi_uc *stbi__process_gif_raster(stbi__context *s, stbi__gif *g) +{ + stbi_uc lzw_cs; + stbi__int32 len, init_code; + stbi__uint32 first; + stbi__int32 codesize, codemask, avail, oldcode, bits, valid_bits, clear; + stbi__gif_lzw *p; + + lzw_cs = stbi__get8(s); + if (lzw_cs > 12) return NULL; + clear = 1 << lzw_cs; + first = 1; + codesize = lzw_cs + 1; + codemask = (1 << codesize) - 1; + bits = 0; + valid_bits = 0; + for (init_code = 0; init_code < clear; init_code++) { + g->codes[init_code].prefix = -1; + g->codes[init_code].first = (stbi_uc)init_code; + g->codes[init_code].suffix = (stbi_uc)init_code; + } + + // support no starting clear code + avail = clear + 2; + oldcode = -1; + + len = 0; + for (;;) { + if (valid_bits < codesize) { + if (len == 0) { + len = stbi__get8(s); // start new block + if (len == 0) + return g->out; + } + --len; + bits |= (stbi__int32)stbi__get8(s) << valid_bits; + valid_bits += 8; + } + else { + stbi__int32 code = bits & codemask; + bits >>= codesize; + valid_bits -= codesize; + // @OPTIMIZE: is there some way we can accelerate the non-clear path? + if (code == clear) { // clear code + codesize = lzw_cs + 1; + codemask = (1 << codesize) - 1; + avail = clear + 2; + oldcode = -1; + first = 0; + } + else if (code == clear + 1) { // end of stream code + stbi__skip(s, len); + while ((len = stbi__get8(s)) > 0) + stbi__skip(s, len); + return g->out; + } + else if (code <= avail) { + if (first) return stbi__errpuc("no clear code", "Corrupt GIF"); + + if (oldcode >= 0) { + p = &g->codes[avail++]; + if (avail > 4096) return stbi__errpuc("too many codes", "Corrupt GIF"); + p->prefix = (stbi__int16)oldcode; + p->first = g->codes[oldcode].first; + p->suffix = (code == avail) ? p->first : g->codes[code].first; + } + else if (code == avail) + return stbi__errpuc("illegal code in raster", "Corrupt GIF"); + + stbi__out_gif_code(g, (stbi__uint16)code); + + if ((avail & codemask) == 0 && avail <= 0x0FFF) { + codesize++; + codemask = (1 << codesize) - 1; + } + + oldcode = code; + } + else { + return stbi__errpuc("illegal code in raster", "Corrupt GIF"); + } + } + } +} + +static void stbi__fill_gif_background(stbi__gif *g, int x0, int y0, int x1, int y1) +{ + int x, y; + stbi_uc *c = g->pal[g->bgindex]; + for (y = y0; y < y1; y += 4 * g->w) { + for (x = x0; x < x1; x += 4) { + stbi_uc *p = &g->out[y + x]; + p[0] = c[2]; + p[1] = c[1]; + p[2] = c[0]; + p[3] = 0; + } + } +} + +// this function is designed to support animated gifs, although stb_image doesn't support it +static stbi_uc *stbi__gif_load_next(stbi__context *s, stbi__gif *g, int *comp, int req_comp) +{ + int i; + stbi_uc *prev_out = 0; + + if (g->out == 0 && !stbi__gif_header(s, g, comp, 0)) + return 0; // stbi__g_failure_reason set by stbi__gif_header + + prev_out = g->out; + g->out = (stbi_uc *)stbi__malloc(4 * g->w * g->h); + if (g->out == 0) return stbi__errpuc("outofmem", "Out of memory"); + + switch ((g->eflags & 0x1C) >> 2) { + case 0: // unspecified (also always used on 1st frame) + stbi__fill_gif_background(g, 0, 0, 4 * g->w, 4 * g->w * g->h); + break; + case 1: // do not dispose + if (prev_out) memcpy(g->out, prev_out, 4 * g->w * g->h); + g->old_out = prev_out; + break; + case 2: // dispose to background + if (prev_out) memcpy(g->out, prev_out, 4 * g->w * g->h); + stbi__fill_gif_background(g, g->start_x, g->start_y, g->max_x, g->max_y); + break; + case 3: // dispose to previous + if (g->old_out) { + for (i = g->start_y; i < g->max_y; i += 4 * g->w) + memcpy(&g->out[i + g->start_x], &g->old_out[i + g->start_x], g->max_x - g->start_x); + } + break; + } + + for (;;) { + switch (stbi__get8(s)) { + case 0x2C: /* Image Descriptor */ + { + int prev_trans = -1; + stbi__int32 x, y, w, h; + stbi_uc *o; + + x = stbi__get16le(s); + y = stbi__get16le(s); + w = stbi__get16le(s); + h = stbi__get16le(s); + if (((x + w) > (g->w)) || ((y + h) > (g->h))) + return stbi__errpuc("bad Image Descriptor", "Corrupt GIF"); + + g->line_size = g->w * 4; + g->start_x = x * 4; + g->start_y = y * g->line_size; + g->max_x = g->start_x + w * 4; + g->max_y = g->start_y + h * g->line_size; + g->cur_x = g->start_x; + g->cur_y = g->start_y; + + g->lflags = stbi__get8(s); + + if (g->lflags & 0x40) { + g->step = 8 * g->line_size; // first interlaced spacing + g->parse = 3; + } + else { + g->step = g->line_size; + g->parse = 0; + } + + if (g->lflags & 0x80) { + stbi__gif_parse_colortable(s, g->lpal, 2 << (g->lflags & 7), g->eflags & 0x01 ? g->transparent : -1); + g->color_table = (stbi_uc *)g->lpal; + } + else if (g->flags & 0x80) { + if (g->transparent >= 0 && (g->eflags & 0x01)) { + prev_trans = g->pal[g->transparent][3]; + g->pal[g->transparent][3] = 0; + } + g->color_table = (stbi_uc *)g->pal; + } + else + return stbi__errpuc("missing color table", "Corrupt GIF"); + + o = stbi__process_gif_raster(s, g); + if (o == NULL) return NULL; + + if (prev_trans != -1) + g->pal[g->transparent][3] = (stbi_uc)prev_trans; + + return o; + } + + case 0x21: // Comment Extension. + { + int len; + if (stbi__get8(s) == 0xF9) { // Graphic Control Extension. + len = stbi__get8(s); + if (len == 4) { + g->eflags = stbi__get8(s); + g->delay = stbi__get16le(s); + g->transparent = stbi__get8(s); + } + else { + stbi__skip(s, len); + break; + } + } + while ((len = stbi__get8(s)) != 0) + stbi__skip(s, len); + break; + } + + case 0x3B: // gif stream termination code + return (stbi_uc *)s; // using '1' causes warning on some compilers + + default: + return stbi__errpuc("unknown code", "Corrupt GIF"); + } + } + + STBI_NOTUSED(req_comp); +} + +static stbi_uc *stbi__gif_load(stbi__context *s, int *x, int *y, int *comp, int req_comp) +{ + stbi_uc *u = 0; + stbi__gif g; + memset(&g, 0, sizeof(g)); + + u = stbi__gif_load_next(s, &g, comp, req_comp); + if (u == (stbi_uc *)s) u = 0; // end of animated gif marker + if (u) { + *x = g.w; + *y = g.h; + if (req_comp && req_comp != 4) + u = stbi__convert_format(u, 4, req_comp, g.w, g.h); + } + else if (g.out) + STBI_FREE(g.out); + + return u; +} + +static int stbi__gif_info(stbi__context *s, int *x, int *y, int *comp) +{ + return stbi__gif_info_raw(s, x, y, comp); +} +#endif + +// ************************************************************************************************* +// Radiance RGBE HDR loader +// originally by Nicolas Schulz +#ifndef STBI_NO_HDR +static int stbi__hdr_test_core(stbi__context *s) +{ + const char *signature = "#?RADIANCE\n"; + int i; + for (i = 0; signature[i]; ++i) + if (stbi__get8(s) != signature[i]) + return 0; + return 1; +} + +static int stbi__hdr_test(stbi__context* s) +{ + int r = stbi__hdr_test_core(s); + stbi__rewind(s); + return r; +} + +#define STBI__HDR_BUFLEN 1024 +static char *stbi__hdr_gettoken(stbi__context *z, char *buffer) +{ + int len = 0; + char c = '\0'; + + c = (char)stbi__get8(z); + + while (!stbi__at_eof(z) && c != '\n') { + buffer[len++] = c; + if (len == STBI__HDR_BUFLEN - 1) { + // flush to end of line + while (!stbi__at_eof(z) && stbi__get8(z) != '\n') + ; + break; + } + c = (char)stbi__get8(z); + } + + buffer[len] = 0; + return buffer; +} + +static void stbi__hdr_convert(float *output, stbi_uc *input, int req_comp) +{ + if (input[3] != 0) { + float f1; + // Exponent + f1 = (float)ldexp(1.0f, input[3] - (int)(128 + 8)); + if (req_comp <= 2) + output[0] = (input[0] + input[1] + input[2]) * f1 / 3; + else { + output[0] = input[0] * f1; + output[1] = input[1] * f1; + output[2] = input[2] * f1; + } + if (req_comp == 2) output[1] = 1; + if (req_comp == 4) output[3] = 1; + } + else { + switch (req_comp) { + case 4: output[3] = 1; /* fallthrough */ + case 3: output[0] = output[1] = output[2] = 0; + break; + case 2: output[1] = 1; /* fallthrough */ + case 1: output[0] = 0; + break; + } + } +} + +static float *stbi__hdr_load(stbi__context *s, int *x, int *y, int *comp, int req_comp) +{ + char buffer[STBI__HDR_BUFLEN]; + char *token; + int valid = 0; + int width, height; + stbi_uc *scanline; + float *hdr_data; + int len; + unsigned char count, value; + int i, j, k, c1, c2, z; + + + // Check identifier + if (strcmp(stbi__hdr_gettoken(s, buffer), "#?RADIANCE") != 0) + return stbi__errpf("not HDR", "Corrupt HDR image"); + + // Parse header + for (;;) { + token = stbi__hdr_gettoken(s, buffer); + if (token[0] == 0) break; + if (strcmp(token, "FORMAT=32-bit_rle_rgbe") == 0) valid = 1; + } + + if (!valid) return stbi__errpf("unsupported format", "Unsupported HDR format"); + + // Parse width and height + // can't use sscanf() if we're not using stdio! + token = stbi__hdr_gettoken(s, buffer); + if (strncmp(token, "-Y ", 3)) return stbi__errpf("unsupported data layout", "Unsupported HDR format"); + token += 3; + height = (int)strtol(token, &token, 10); + while (*token == ' ') ++token; + if (strncmp(token, "+X ", 3)) return stbi__errpf("unsupported data layout", "Unsupported HDR format"); + token += 3; + width = (int)strtol(token, NULL, 10); + + *x = width; + *y = height; + + if (comp) *comp = 3; + if (req_comp == 0) req_comp = 3; + + // Read data + hdr_data = (float *)stbi__malloc(height * width * req_comp * sizeof(float)); + + // Load image data + // image data is stored as some number of sca + if (width < 8 || width >= 32768) { + // Read flat data + for (j = 0; j < height; ++j) { + for (i = 0; i < width; ++i) { + stbi_uc rgbe[4]; + main_decode_loop: + stbi__getn(s, rgbe, 4); + stbi__hdr_convert(hdr_data + j * width * req_comp + i * req_comp, rgbe, req_comp); + } + } + } + else { + // Read RLE-encoded data + scanline = NULL; + + for (j = 0; j < height; ++j) { + c1 = stbi__get8(s); + c2 = stbi__get8(s); + len = stbi__get8(s); + if (c1 != 2 || c2 != 2 || (len & 0x80)) { + // not run-length encoded, so we have to actually use THIS data as a decoded + // pixel (note this can't be a valid pixel--one of RGB must be >= 128) + stbi_uc rgbe[4]; + rgbe[0] = (stbi_uc)c1; + rgbe[1] = (stbi_uc)c2; + rgbe[2] = (stbi_uc)len; + rgbe[3] = (stbi_uc)stbi__get8(s); + stbi__hdr_convert(hdr_data, rgbe, req_comp); + i = 1; + j = 0; + STBI_FREE(scanline); + goto main_decode_loop; // yes, this makes no sense + } + len <<= 8; + len |= stbi__get8(s); + if (len != width) { STBI_FREE(hdr_data); STBI_FREE(scanline); return stbi__errpf("invalid decoded scanline length", "corrupt HDR"); } + if (scanline == NULL) scanline = (stbi_uc *)stbi__malloc(width * 4); + + for (k = 0; k < 4; ++k) { + i = 0; + while (i < width) { + count = stbi__get8(s); + if (count > 128) { + // Run + value = stbi__get8(s); + count -= 128; + for (z = 0; z < count; ++z) + scanline[i++ * 4 + k] = value; + } + else { + // Dump + for (z = 0; z < count; ++z) + scanline[i++ * 4 + k] = stbi__get8(s); + } + } + } + for (i = 0; i < width; ++i) + stbi__hdr_convert(hdr_data + (j*width + i)*req_comp, scanline + i * 4, req_comp); + } + STBI_FREE(scanline); + } + + return hdr_data; +} + +static int stbi__hdr_info(stbi__context *s, int *x, int *y, int *comp) +{ + char buffer[STBI__HDR_BUFLEN]; + char *token; + int valid = 0; + + if (stbi__hdr_test(s) == 0) { + stbi__rewind(s); + return 0; + } + + for (;;) { + token = stbi__hdr_gettoken(s, buffer); + if (token[0] == 0) break; + if (strcmp(token, "FORMAT=32-bit_rle_rgbe") == 0) valid = 1; + } + + if (!valid) { + stbi__rewind(s); + return 0; + } + token = stbi__hdr_gettoken(s, buffer); + if (strncmp(token, "-Y ", 3)) { + stbi__rewind(s); + return 0; + } + token += 3; + *y = (int)strtol(token, &token, 10); + while (*token == ' ') ++token; + if (strncmp(token, "+X ", 3)) { + stbi__rewind(s); + return 0; + } + token += 3; + *x = (int)strtol(token, NULL, 10); + *comp = 3; + return 1; +} +#endif // STBI_NO_HDR + +#ifndef STBI_NO_BMP +static int stbi__bmp_info(stbi__context *s, int *x, int *y, int *comp) +{ + void *p; + stbi__bmp_data info; + + info.all_a = 255; + p = stbi__bmp_parse_header(s, &info); + stbi__rewind(s); + if (p == NULL) + return 0; + *x = s->img_x; + *y = s->img_y; + *comp = info.ma ? 4 : 3; + return 1; +} +#endif + +#ifndef STBI_NO_PSD +static int stbi__psd_info(stbi__context *s, int *x, int *y, int *comp) +{ + int channelCount; + if (stbi__get32be(s) != 0x38425053) { + stbi__rewind(s); + return 0; + } + if (stbi__get16be(s) != 1) { + stbi__rewind(s); + return 0; + } + stbi__skip(s, 6); + channelCount = stbi__get16be(s); + if (channelCount < 0 || channelCount > 16) { + stbi__rewind(s); + return 0; + } + *y = stbi__get32be(s); + *x = stbi__get32be(s); + if (stbi__get16be(s) != 8) { + stbi__rewind(s); + return 0; + } + if (stbi__get16be(s) != 3) { + stbi__rewind(s); + return 0; + } + *comp = 4; + return 1; +} +#endif + +#ifndef STBI_NO_PIC +static int stbi__pic_info(stbi__context *s, int *x, int *y, int *comp) +{ + int act_comp = 0, num_packets = 0, chained; + stbi__pic_packet packets[10]; + + if (!stbi__pic_is4(s, "\x53\x80\xF6\x34")) { + stbi__rewind(s); + return 0; + } + + stbi__skip(s, 88); + + *x = stbi__get16be(s); + *y = stbi__get16be(s); + if (stbi__at_eof(s)) { + stbi__rewind(s); + return 0; + } + if ((*x) != 0 && (1 << 28) / (*x) < (*y)) { + stbi__rewind(s); + return 0; + } + + stbi__skip(s, 8); + + do { + stbi__pic_packet *packet; + + if (num_packets == sizeof(packets) / sizeof(packets[0])) + return 0; + + packet = &packets[num_packets++]; + chained = stbi__get8(s); + packet->size = stbi__get8(s); + packet->type = stbi__get8(s); + packet->channel = stbi__get8(s); + act_comp |= packet->channel; + + if (stbi__at_eof(s)) { + stbi__rewind(s); + return 0; + } + if (packet->size != 8) { + stbi__rewind(s); + return 0; + } + } while (chained); + + *comp = (act_comp & 0x10 ? 4 : 3); + + return 1; +} +#endif + +// ************************************************************************************************* +// Portable Gray Map and Portable Pixel Map loader +// by Ken Miller +// +// PGM: http://netpbm.sourceforge.net/doc/pgm.html +// PPM: http://netpbm.sourceforge.net/doc/ppm.html +// +// Known limitations: +// Does not support comments in the header section +// Does not support ASCII image data (formats P2 and P3) +// Does not support 16-bit-per-channel + +#ifndef STBI_NO_PNM + +static int stbi__pnm_test(stbi__context *s) +{ + char p, t; + p = (char)stbi__get8(s); + t = (char)stbi__get8(s); + if (p != 'P' || (t != '5' && t != '6')) { + stbi__rewind(s); + return 0; + } + return 1; +} + +static stbi_uc *stbi__pnm_load(stbi__context *s, int *x, int *y, int *comp, int req_comp) +{ + stbi_uc *out; + if (!stbi__pnm_info(s, (int *)&s->img_x, (int *)&s->img_y, (int *)&s->img_n)) + return 0; + *x = s->img_x; + *y = s->img_y; + *comp = s->img_n; + + out = (stbi_uc *)stbi__malloc(s->img_n * s->img_x * s->img_y); + if (!out) return stbi__errpuc("outofmem", "Out of memory"); + stbi__getn(s, out, s->img_n * s->img_x * s->img_y); + + if (req_comp && req_comp != s->img_n) { + out = stbi__convert_format(out, s->img_n, req_comp, s->img_x, s->img_y); + if (out == NULL) return out; // stbi__convert_format frees input on failure + } + return out; +} + +static int stbi__pnm_isspace(char c) +{ + return c == ' ' || c == '\t' || c == '\n' || c == '\v' || c == '\f' || c == '\r'; +} + +static void stbi__pnm_skip_whitespace(stbi__context *s, char *c) +{ + for (;;) { + while (!stbi__at_eof(s) && stbi__pnm_isspace(*c)) + *c = (char)stbi__get8(s); + + if (stbi__at_eof(s) || *c != '#') + break; + + while (!stbi__at_eof(s) && *c != '\n' && *c != '\r') + *c = (char)stbi__get8(s); + } +} + +static int stbi__pnm_isdigit(char c) +{ + return c >= '0' && c <= '9'; +} + +static int stbi__pnm_getinteger(stbi__context *s, char *c) +{ + int value = 0; + + while (!stbi__at_eof(s) && stbi__pnm_isdigit(*c)) { + value = value * 10 + (*c - '0'); + *c = (char)stbi__get8(s); + } + + return value; +} + +static int stbi__pnm_info(stbi__context *s, int *x, int *y, int *comp) +{ + int maxv; + char c, p, t; + + stbi__rewind(s); + + // Get identifier + p = (char)stbi__get8(s); + t = (char)stbi__get8(s); + if (p != 'P' || (t != '5' && t != '6')) { + stbi__rewind(s); + return 0; + } + + *comp = (t == '6') ? 3 : 1; // '5' is 1-component .pgm; '6' is 3-component .ppm + + c = (char)stbi__get8(s); + stbi__pnm_skip_whitespace(s, &c); + + *x = stbi__pnm_getinteger(s, &c); // read width + stbi__pnm_skip_whitespace(s, &c); + + *y = stbi__pnm_getinteger(s, &c); // read height + stbi__pnm_skip_whitespace(s, &c); + + maxv = stbi__pnm_getinteger(s, &c); // read max value + + if (maxv > 255) + return stbi__err("max value > 255", "PPM image not 8-bit"); + else + return 1; +} +#endif + +static int stbi__info_main(stbi__context *s, int *x, int *y, int *comp) +{ +#ifndef STBI_NO_JPEG + if (stbi__jpeg_info(s, x, y, comp)) return 1; +#endif + +#ifndef STBI_NO_PNG + if (stbi__png_info(s, x, y, comp)) return 1; +#endif + +#ifndef STBI_NO_GIF + if (stbi__gif_info(s, x, y, comp)) return 1; +#endif + +#ifndef STBI_NO_BMP + if (stbi__bmp_info(s, x, y, comp)) return 1; +#endif + +#ifndef STBI_NO_PSD + if (stbi__psd_info(s, x, y, comp)) return 1; +#endif + +#ifndef STBI_NO_PIC + if (stbi__pic_info(s, x, y, comp)) return 1; +#endif + +#ifndef STBI_NO_PNM + if (stbi__pnm_info(s, x, y, comp)) return 1; +#endif + +#ifndef STBI_NO_HDR + if (stbi__hdr_info(s, x, y, comp)) return 1; +#endif + + // test tga last because it's a crappy test! +#ifndef STBI_NO_TGA + if (stbi__tga_info(s, x, y, comp)) + return 1; +#endif + return stbi__err("unknown image type", "Image not of any known type, or corrupt"); +} + +#ifndef STBI_NO_STDIO +STBIDEF int stbi_info(char const *filename, int *x, int *y, int *comp) +{ + FILE *f = stbi__fopen(filename, "rb"); + int result; + if (!f) return stbi__err("can't fopen", "Unable to open file"); + result = stbi_info_from_file(f, x, y, comp); + fclose(f); + return result; +} + +STBIDEF int stbi_info_from_file(FILE *f, int *x, int *y, int *comp) +{ + int r; + stbi__context s; + long pos = ftell(f); + stbi__start_file(&s, f); + r = stbi__info_main(&s, x, y, comp); + fseek(f, pos, SEEK_SET); + return r; +} +#endif // !STBI_NO_STDIO + +STBIDEF int stbi_info_from_memory(stbi_uc const *buffer, int len, int *x, int *y, int *comp) +{ + stbi__context s; + stbi__start_mem(&s, buffer, len); + return stbi__info_main(&s, x, y, comp); +} + +STBIDEF int stbi_info_from_callbacks(stbi_io_callbacks const *c, void *user, int *x, int *y, int *comp) +{ + stbi__context s; + stbi__start_callbacks(&s, (stbi_io_callbacks *)c, user); + return stbi__info_main(&s, x, y, comp); +} + +#endif // STB_IMAGE_IMPLEMENTATION + +/* +revision history: +2.10 (2016-01-22) avoid warning introduced in 2.09 by STBI_REALLOC_SIZED +2.09 (2016-01-16) allow comments in PNM files +16-bit-per-pixel TGA (not bit-per-component) +info() for TGA could break due to .hdr handling +info() for BMP to shares code instead of sloppy parse +can use STBI_REALLOC_SIZED if allocator doesn't support realloc +code cleanup +2.08 (2015-09-13) fix to 2.07 cleanup, reading RGB PSD as RGBA +2.07 (2015-09-13) fix compiler warnings +partial animated GIF support +limited 16-bpc PSD support +#ifdef unused functions +bug with < 92 byte PIC,PNM,HDR,TGA +2.06 (2015-04-19) fix bug where PSD returns wrong '*comp' value +2.05 (2015-04-19) fix bug in progressive JPEG handling, fix warning +2.04 (2015-04-15) try to re-enable SIMD on MinGW 64-bit +2.03 (2015-04-12) extra corruption checking (mmozeiko) +stbi_set_flip_vertically_on_load (nguillemot) +fix NEON support; fix mingw support +2.02 (2015-01-19) fix incorrect assert, fix warning +2.01 (2015-01-17) fix various warnings; suppress SIMD on gcc 32-bit without -msse2 +2.00b (2014-12-25) fix STBI_MALLOC in progressive JPEG +2.00 (2014-12-25) optimize JPG, including x86 SSE2 & NEON SIMD (ryg) +progressive JPEG (stb) +PGM/PPM support (Ken Miller) +STBI_MALLOC,STBI_REALLOC,STBI_FREE +GIF bugfix -- seemingly never worked +STBI_NO_*, STBI_ONLY_* +1.48 (2014-12-14) fix incorrectly-named assert() +1.47 (2014-12-14) 1/2/4-bit PNG support, both direct and paletted (Omar Cornut & stb) +optimize PNG (ryg) +fix bug in interlaced PNG with user-specified channel count (stb) +1.46 (2014-08-26) +fix broken tRNS chunk (colorkey-style transparency) in non-paletted PNG +1.45 (2014-08-16) +fix MSVC-ARM internal compiler error by wrapping malloc +1.44 (2014-08-07) +various warning fixes from Ronny Chevalier +1.43 (2014-07-15) +fix MSVC-only compiler problem in code changed in 1.42 +1.42 (2014-07-09) +don't define _CRT_SECURE_NO_WARNINGS (affects user code) +fixes to stbi__cleanup_jpeg path +added STBI_ASSERT to avoid requiring assert.h +1.41 (2014-06-25) +fix search&replace from 1.36 that messed up comments/error messages +1.40 (2014-06-22) +fix gcc struct-initialization warning +1.39 (2014-06-15) +fix to TGA optimization when req_comp != number of components in TGA; +fix to GIF loading because BMP wasn't rewinding (whoops, no GIFs in my test suite) +add support for BMP version 5 (more ignored fields) +1.38 (2014-06-06) +suppress MSVC warnings on integer casts truncating values +fix accidental rename of 'skip' field of I/O +1.37 (2014-06-04) +remove duplicate typedef +1.36 (2014-06-03) +convert to header file single-file library +if de-iphone isn't set, load iphone images color-swapped instead of returning NULL +1.35 (2014-05-27) +various warnings +fix broken STBI_SIMD path +fix bug where stbi_load_from_file no longer left file pointer in correct place +fix broken non-easy path for 32-bit BMP (possibly never used) +TGA optimization by Arseny Kapoulkine +1.34 (unknown) +use STBI_NOTUSED in stbi__resample_row_generic(), fix one more leak in tga failure case +1.33 (2011-07-14) +make stbi_is_hdr work in STBI_NO_HDR (as specified), minor compiler-friendly improvements +1.32 (2011-07-13) +support for "info" function for all supported filetypes (SpartanJ) +1.31 (2011-06-20) +a few more leak fixes, bug in PNG handling (SpartanJ) +1.30 (2011-06-11) +added ability to load files via callbacks to accomidate custom input streams (Ben Wenger) +removed deprecated format-specific test/load functions +removed support for installable file formats (stbi_loader) -- would have been broken for IO callbacks anyway +error cases in bmp and tga give messages and don't leak (Raymond Barbiero, grisha) +fix inefficiency in decoding 32-bit BMP (David Woo) +1.29 (2010-08-16) +various warning fixes from Aurelien Pocheville +1.28 (2010-08-01) +fix bug in GIF palette transparency (SpartanJ) +1.27 (2010-08-01) +cast-to-stbi_uc to fix warnings +1.26 (2010-07-24) +fix bug in file buffering for PNG reported by SpartanJ +1.25 (2010-07-17) +refix trans_data warning (Won Chun) +1.24 (2010-07-12) +perf improvements reading from files on platforms with lock-heavy fgetc() +minor perf improvements for jpeg +deprecated type-specific functions so we'll get feedback if they're needed +attempt to fix trans_data warning (Won Chun) +1.23 fixed bug in iPhone support +1.22 (2010-07-10) +removed image *writing* support +stbi_info support from Jetro Lauha +GIF support from Jean-Marc Lienher +iPhone PNG-extensions from James Brown +warning-fixes from Nicolas Schulz and Janez Zemva (i.stbi__err. Janez (U+017D)emva) +1.21 fix use of 'stbi_uc' in header (reported by jon blow) +1.20 added support for Softimage PIC, by Tom Seddon +1.19 bug in interlaced PNG corruption check (found by ryg) +1.18 (2008-08-02) +fix a threading bug (local mutable static) +1.17 support interlaced PNG +1.16 major bugfix - stbi__convert_format converted one too many pixels +1.15 initialize some fields for thread safety +1.14 fix threadsafe conversion bug +header-file-only version (#define STBI_HEADER_FILE_ONLY before including) +1.13 threadsafe +1.12 const qualifiers in the API +1.11 Support installable IDCT, colorspace conversion routines +1.10 Fixes for 64-bit (don't use "unsigned long") +optimized upsampling by Fabian "ryg" Giesen +1.09 Fix format-conversion for PSD code (bad global variables!) +1.08 Thatcher Ulrich's PSD code integrated by Nicolas Schulz +1.07 attempt to fix C++ warning/errors again +1.06 attempt to fix C++ warning/errors again +1.05 fix TGA loading to return correct *comp and use good luminance calc +1.04 default float alpha is 1, not 255; use 'void *' for stbi_image_free +1.03 bugfixes to STBI_NO_STDIO, STBI_NO_HDR +1.02 support for (subset of) HDR files, float interface for preferred access to them +1.01 fix bug: possible bug in handling right-side up bmps... not sure +fix bug: the stbi__bmp_load() and stbi__tga_load() functions didn't work at all +1.00 interface to zlib that skips zlib header +0.99 correct handling of alpha in palette +0.98 TGA loader by lonesock; dynamically add loaders (untested) +0.97 jpeg errors on too large a file; also catch another malloc failure +0.96 fix detection of invalid v value - particleman@mollyrocket forum +0.95 during header scan, seek to markers in case of padding +0.94 STBI_NO_STDIO to disable stdio usage; rename all #defines the same +0.93 handle jpegtran output; verbose errors +0.92 read 4,8,16,24,32-bit BMP files of several formats +0.91 output 24-bit Windows 3.0 BMP files +0.90 fix a few more warnings; bump version number to approach 1.0 +0.61 bugfixes due to Marc LeBlanc, Christopher Lloyd +0.60 fix compiling as c++ +0.59 fix warnings: merge Dave Moore's -Wall fixes +0.58 fix bug: zlib uncompressed mode len/nlen was wrong endian +0.57 fix bug: jpg last huffman symbol before marker was >9 bits but less than 16 available +0.56 fix bug: zlib uncompressed mode len vs. nlen +0.55 fix bug: restart_interval not initialized to 0 +0.54 allow NULL for 'int *comp' +0.53 fix bug in png 3->4; speedup png decoding +0.52 png handles req_comp=3,4 directly; minor cleanup; jpeg comments +0.51 obey req_comp requests, 1-component jpegs return as 1-component, +on 'test' only check type, not whether we support this variant +0.50 (2006-11-19) +first released version +*/ \ No newline at end of file