diff --git a/Codec/Image/STB.hs b/Codec/Image/STB.hs --- a/Codec/Image/STB.hs +++ b/Codec/Image/STB.hs @@ -1,20 +1,23 @@ -------------------------------------------------------------------------------- -- Module : Codec.Image.STB --- Version : 0.2 +-- Version : 0.2.1 -- License : Public Domain -- Author : Balazs Komuves -- Maintainer : bkomuves (plus) hackage (at) gmail (dot) com -- Stability : experimental -- Portability : portable(?), requires FFI and CPP --- Tested with : GHC 6.10.1 +-- Tested with : GHC 6.12.3 -------------------------------------------------------------------------------- -- | A wrapper around @stb_image@, Sean Barrett's public domain JPEG\/PNG decoder. -- The original can be found at . --- The version of @stb_image@ used here is @stbi-1.18@. +-- The version of @stb_image@ used here is @stbi-1.33@. -- The current list of (partially) supported formats is JPEG, PNG, TGA, BMP, PSD. --- Please note that the library is not (fully) thread-safe! +-- +-- Please note that the library is not (fully) thread-safe! Furthermore, +-- the library does not give any guarantee in case of invalid input; +-- in particular it is a security risk to load untrusted image files. {-# LANGUAGE ForeignFunctionInterface, CPP #-} {-# CFILES cbits/stb_image.c #-} -- for Hugs (?) @@ -29,7 +32,7 @@ -------------------------------------------------------------------------------- -import Data.Bitmap.IO +import Data.Bitmap.Pure -- Data.Bitmap.IO import Control.Monad (liftM) import Control.Exception diff --git a/cbits/stb_image.c b/cbits/stb_image.c --- a/cbits/stb_image.c +++ b/cbits/stb_image.c @@ -1,3891 +1,4673 @@ -/* stbi-1.18 - public domain JPEG/PNG reader - http://nothings.org/stb_image.c - when you control the images you're loading - - 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, no oddball channel decimations) - PNG 8-bit only - BMP non-1bpp, non-RLE - TGA (not sure what subset, if a subset) - PSD (composited view only, no extra channels) - HDR (radiance rgbE format) - writes BMP,TGA (define STBI_NO_WRITE to remove code) - decoded from memory or through stdio FILE (define STBI_NO_STDIO to remove code) - supports installable dequantizing-IDCT, YCbCr-to-RGB conversion (define STBI_SIMD) - - TODO: - stbi_info_* - - history: - 1.18 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 -*/ - - -#ifndef STBI_INCLUDE_STB_IMAGE_H -#define STBI_INCLUDE_STB_IMAGE_H - -//// begin header file //////////////////////////////////////////////////// -// -// Limitations: -// - no progressive/interlaced support (jpeg, png) -// - 8-bit samples only (jpeg, png) -// - not threadsafe -// - channel subsampling of at most 2 in each dimension (jpeg) -// - no delayed line count (jpeg) -- IJG doesn't support either -// -// Basic usage (see HDR discussion below): -// int x,y,n; -// unsigned char *data = stbi_load(filename, &x, &y, &n, 0); -// // ... 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 -// stbi_image_free(data) -// -// Standard parameters: -// int *x -- outputs image width in pixels -// int *y -- outputs image height in pixels -// int *comp -- outputs # of image components in image file -// 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, -// 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. -// -// An output image with N components has the following components interleaved -// in this order in each pixel: -// -// N=#comp components -// 1 grey -// 2 grey, alpha -// 3 red, green, blue -// 4 red, green, blue, alpha -// -// If image loading fails for any reason, the return value will be NULL, -// and *x, *y, *comp will be unchanged. The function stbi_failure_reason() -// can be queried for an extremely brief, end-user unfriendly explanation -// of why the load failed. Define STBI_NO_FAILURE_STRINGS to avoid -// compiling these strings at all, and STBI_FAILURE_USERMSG to get slightly -// more user-friendly ones. -// -// Paletted PNG and BMP images are automatically depalettized. -// -// -// =========================================================================== -// -// HDR image support (disable by defining STBI_NO_HDR) -// -// stb_image now supports loading HDR images in general, and currently -// the Radiance .HDR file format, although the support is provided -// generically. You can still load any file through the existing interface; -// if you attempt to load an HDR file, it will be automatically remapped to -// LDR, assuming gamma 2.2 and an arbitrary scale factor defaulting to 1; -// both of these constants can be reconfigured through this interface: -// -// stbi_hdr_to_ldr_gamma(2.2f); -// stbi_hdr_to_ldr_scale(1.0f); -// -// (note, do not use _inverse_ constants; stbi_image will invert them -// appropriately). -// -// Additionally, there is a new, parallel interface for loading files as -// (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: -// -// stbi_ldr_to_hdr_scale(1.0f); -// stbi_ldr_to_hdr_gamma(2.2f); -// -// Finally, given a filename (or an open file or memory block--see header -// file for details) containing image data, you can query for the "most -// appropriate" interface to use (that is, whether the image is HDR or -// not), using: -// -// stbi_is_hdr(char *filename); - -#ifndef STBI_NO_STDIO -#include -#endif - -#define STBI_VERSION 1 - -enum -{ - STBI_default = 0, // only used for req_comp - - STBI_grey = 1, - STBI_grey_alpha = 2, - STBI_rgb = 3, - STBI_rgb_alpha = 4, -}; - -typedef unsigned char stbi_uc; - -#ifdef __cplusplus -extern "C" { -#endif - -// WRITING API - -#if !defined(STBI_NO_WRITE) && !defined(STBI_NO_STDIO) -// write a BMP/TGA file given tightly packed 'comp' channels (no padding, nor bmp-stride-padding) -// (you must include the appropriate extension in the filename). -// returns TRUE on success, FALSE if couldn't open file, error writing file -extern int stbi_write_bmp (char const *filename, int x, int y, int comp, void *data); -extern int stbi_write_tga (char const *filename, int x, int y, int comp, void *data); -#endif - -// PRIMARY API - works on images of any type - -// load image by filename, open file, or memory buffer -#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); -extern int stbi_info_from_file (FILE *f, int *x, int *y, int *comp); -#endif -extern stbi_uc *stbi_load_from_memory(stbi_uc const *buffer, int len, int *x, int *y, int *comp, int req_comp); -// for stbi_load_from_file, file pointer is left pointing immediately after image - -#ifndef STBI_NO_HDR -#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_memory(stbi_uc const *buffer, int len, 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); - -#endif // STBI_NO_HDR - -// get a VERY brief reason for failure -// NOT THREADSAFE -extern char *stbi_failure_reason (void); - -// free the loaded image -- this is just free() -extern 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_is_hdr_from_memory(stbi_uc const *buffer, int len); -#ifndef STBI_NO_STDIO -extern int stbi_info (char const *filename, int *x, int *y, int *comp); -extern int stbi_is_hdr (char const *filename); -extern int stbi_is_hdr_from_file(FILE *f); -#endif - -// 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); - -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); - -// TYPE-SPECIFIC ACCESS - -// is it a jpeg? -extern int stbi_jpeg_test_memory (stbi_uc const *buffer, int len); -extern stbi_uc *stbi_jpeg_load_from_memory(stbi_uc const *buffer, int len, int *x, int *y, int *comp, int req_comp); -extern int stbi_jpeg_info_from_memory(stbi_uc const *buffer, int len, int *x, int *y, int *comp); - -#ifndef STBI_NO_STDIO -extern stbi_uc *stbi_jpeg_load (char const *filename, int *x, int *y, int *comp, int req_comp); -extern int stbi_jpeg_test_file (FILE *f); -extern stbi_uc *stbi_jpeg_load_from_file (FILE *f, int *x, int *y, int *comp, int req_comp); - -extern int stbi_jpeg_info (char const *filename, int *x, int *y, int *comp); -extern int stbi_jpeg_info_from_file (FILE *f, int *x, int *y, int *comp); -#endif - -// is it a png? -extern int stbi_png_test_memory (stbi_uc const *buffer, int len); -extern stbi_uc *stbi_png_load_from_memory (stbi_uc const *buffer, int len, int *x, int *y, int *comp, int req_comp); -extern int stbi_png_info_from_memory (stbi_uc const *buffer, int len, int *x, int *y, int *comp); - -#ifndef STBI_NO_STDIO -extern stbi_uc *stbi_png_load (char const *filename, int *x, int *y, int *comp, int req_comp); -extern int stbi_png_info (char const *filename, int *x, int *y, int *comp); -extern int stbi_png_test_file (FILE *f); -extern stbi_uc *stbi_png_load_from_file (FILE *f, int *x, int *y, int *comp, int req_comp); -extern int stbi_png_info_from_file (FILE *f, int *x, int *y, int *comp); -#endif - -// is it a bmp? -extern int stbi_bmp_test_memory (stbi_uc const *buffer, int len); - -extern stbi_uc *stbi_bmp_load (char const *filename, int *x, int *y, int *comp, int req_comp); -extern stbi_uc *stbi_bmp_load_from_memory (stbi_uc const *buffer, int len, int *x, int *y, int *comp, int req_comp); -#ifndef STBI_NO_STDIO -extern int stbi_bmp_test_file (FILE *f); -extern stbi_uc *stbi_bmp_load_from_file (FILE *f, int *x, int *y, int *comp, int req_comp); -#endif - -// is it a tga? -extern int stbi_tga_test_memory (stbi_uc const *buffer, int len); - -extern stbi_uc *stbi_tga_load (char const *filename, int *x, int *y, int *comp, int req_comp); -extern stbi_uc *stbi_tga_load_from_memory (stbi_uc const *buffer, int len, int *x, int *y, int *comp, int req_comp); -#ifndef STBI_NO_STDIO -extern int stbi_tga_test_file (FILE *f); -extern stbi_uc *stbi_tga_load_from_file (FILE *f, int *x, int *y, int *comp, int req_comp); -#endif - -// is it a psd? -extern int stbi_psd_test_memory (stbi_uc const *buffer, int len); - -extern stbi_uc *stbi_psd_load (char const *filename, int *x, int *y, int *comp, int req_comp); -extern stbi_uc *stbi_psd_load_from_memory (stbi_uc const *buffer, int len, int *x, int *y, int *comp, int req_comp); -#ifndef STBI_NO_STDIO -extern int stbi_psd_test_file (FILE *f); -extern stbi_uc *stbi_psd_load_from_file (FILE *f, int *x, int *y, int *comp, int req_comp); -#endif - -// is it an hdr? -extern int stbi_hdr_test_memory (stbi_uc const *buffer, int len); - -extern float * stbi_hdr_load (char const *filename, int *x, int *y, int *comp, int req_comp); -extern float * stbi_hdr_load_from_memory (stbi_uc const *buffer, int len, int *x, int *y, int *comp, int req_comp); -#ifndef STBI_NO_STDIO -extern int stbi_hdr_test_file (FILE *f); -extern float * stbi_hdr_load_from_file (FILE *f, int *x, int *y, int *comp, int req_comp); -#endif - -// define new loaders -typedef struct -{ - int (*test_memory)(stbi_uc const *buffer, int len); - stbi_uc * (*load_from_memory)(stbi_uc const *buffer, int len, int *x, int *y, int *comp, int req_comp); - #ifndef STBI_NO_STDIO - int (*test_file)(FILE *f); - stbi_uc * (*load_from_file)(FILE *f, int *x, int *y, int *comp, int req_comp); - #endif -} stbi_loader; - -// register a loader by filling out the above structure (you must defined ALL functions) -// returns 1 if added or already added, 0 if not added (too many loaders) -// NOT THREADSAFE -extern int stbi_register_loader(stbi_loader *loader); - -// define faster low-level operations (typically SIMD support) -#if STBI_SIMD -typedef void (*stbi_idct_8x8)(uint8 *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)(uint8 *output, uint8 const *y, uint8 const *cb, uint8 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 - -#ifdef __cplusplus -} -#endif - -// -// -//// end header file ///////////////////////////////////////////////////// -#endif // STBI_INCLUDE_STB_IMAGE_H - -#ifndef STBI_HEADER_FILE_ONLY - -#ifndef STBI_NO_HDR -#include // ldexp -#include // strcmp -#endif - -#ifndef STBI_NO_STDIO -#include -#endif -#include -#include -#include -#include - -#ifndef _MSC_VER - #ifdef __cplusplus - #define __forceinline inline - #else - #define __forceinline - #endif -#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]; - -#if defined(STBI_NO_STDIO) && !defined(STBI_NO_WRITE) -#define STBI_NO_WRITE -#endif - -////////////////////////////////////////////////////////////////////////////// -// -// Generic API that works on all image types -// - -// this is not threadsafe -static char *failure_reason; - -char *stbi_failure_reason(void) -{ - return failure_reason; -} - -static int e(char *str) -{ - failure_reason = str; - return 0; -} - -#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); -} - -#define MAX_LOADERS 32 -stbi_loader *loaders[MAX_LOADERS]; -static int max_loaders = 0; - -int stbi_register_loader(stbi_loader *loader) -{ - int i; - for (i=0; i < MAX_LOADERS; ++i) { - // already present? - if (loaders[i] == loader) - return 1; - // end of the list? - if (loaders[i] == NULL) { - loaders[i] = loader; - max_loaders = i+1; - return 1; - } - } - // no room for it - return 0; -} - -#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 - -#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) -{ - int i; - if (stbi_jpeg_test_file(f)) - return stbi_jpeg_load_from_file(f,x,y,comp,req_comp); - if (stbi_png_test_file(f)) - return stbi_png_load_from_file(f,x,y,comp,req_comp); - if (stbi_bmp_test_file(f)) - return stbi_bmp_load_from_file(f,x,y,comp,req_comp); - if (stbi_psd_test_file(f)) - return stbi_psd_load_from_file(f,x,y,comp,req_comp); - #ifndef STBI_NO_HDR - if (stbi_hdr_test_file(f)) { - float *hdr = stbi_hdr_load_from_file(f, x,y,comp,req_comp); - return hdr_to_ldr(hdr, *x, *y, req_comp ? req_comp : *comp); - } - #endif - for (i=0; i < max_loaders; ++i) - if (loaders[i]->test_file(f)) - return loaders[i]->load_from_file(f,x,y,comp,req_comp); - // test tga last because it's a crappy test! - if (stbi_tga_test_file(f)) - return stbi_tga_load_from_file(f,x,y,comp,req_comp); - return epuc("unknown image type", "Image not of any known type, or corrupt"); -} -#endif - -unsigned char *stbi_load_from_memory(stbi_uc const *buffer, int len, int *x, int *y, int *comp, int req_comp) -{ - int i; - if (stbi_jpeg_test_memory(buffer,len)) - return stbi_jpeg_load_from_memory(buffer,len,x,y,comp,req_comp); - if (stbi_png_test_memory(buffer,len)) - return stbi_png_load_from_memory(buffer,len,x,y,comp,req_comp); - if (stbi_bmp_test_memory(buffer,len)) - return stbi_bmp_load_from_memory(buffer,len,x,y,comp,req_comp); - if (stbi_psd_test_memory(buffer,len)) - return stbi_psd_load_from_memory(buffer,len,x,y,comp,req_comp); - #ifndef STBI_NO_HDR - if (stbi_hdr_test_memory(buffer, len)) { - float *hdr = stbi_hdr_load_from_memory(buffer, len,x,y,comp,req_comp); - return hdr_to_ldr(hdr, *x, *y, req_comp ? req_comp : *comp); - } - #endif - for (i=0; i < max_loaders; ++i) - if (loaders[i]->test_memory(buffer,len)) - return loaders[i]->load_from_memory(buffer,len,x,y,comp,req_comp); - // test tga last because it's a crappy test! - if (stbi_tga_test_memory(buffer,len)) - return stbi_tga_load_from_memory(buffer,len,x,y,comp,req_comp); - return epuc("unknown image type", "Image not of any known type, or corrupt"); -} - -#ifndef STBI_NO_HDR - -#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) -{ - unsigned char *data; - #ifndef STBI_NO_HDR - if (stbi_hdr_test_file(f)) - return stbi_hdr_load_from_file(f,x,y,comp,req_comp); - #endif - data = stbi_load_from_file(f, 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"); -} -#endif - -float *stbi_loadf_from_memory(stbi_uc const *buffer, int len, int *x, int *y, int *comp, int req_comp) -{ - stbi_uc *data; - #ifndef STBI_NO_HDR - if (stbi_hdr_test_memory(buffer, len)) - return stbi_hdr_load_from_memory(buffer, len,x,y,comp,req_comp); - #endif - data = stbi_load_from_memory(buffer, len, 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"); -} -#endif - -// 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 - return stbi_hdr_test_memory(buffer, len); - #else - 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 - return stbi_hdr_test_file(f); - #else - return 0; - #endif -} - -#endif - -// @TODO: get image dimensions & components without fully decoding -#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); -#endif -extern int stbi_info_from_memory(stbi_uc const *buffer, int len, int *x, int *y, int *comp); - -#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, -}; - -typedef struct -{ - uint32 img_x, img_y; - int img_n, img_out_n; - - #ifndef STBI_NO_STDIO - FILE *img_file; - #endif - uint8 *img_buffer, *img_buffer_end; -} stbi; - -#ifndef STBI_NO_STDIO -static void start_file(stbi *s, FILE *f) -{ - s->img_file = f; -} -#endif - -static void start_mem(stbi *s, uint8 const *buffer, int len) -{ -#ifndef STBI_NO_STDIO - s->img_file = NULL; -#endif - s->img_buffer = (uint8 *) buffer; - s->img_buffer_end = (uint8 *) buffer+len; -} - -__forceinline static int get8(stbi *s) -{ -#ifndef STBI_NO_STDIO - if (s->img_file) { - int c = fgetc(s->img_file); - return c == EOF ? 0 : c; - } -#endif - if (s->img_buffer < s->img_buffer_end) - return *s->img_buffer++; - return 0; -} - -__forceinline static int at_eof(stbi *s) -{ -#ifndef STBI_NO_STDIO - if (s->img_file) - return feof(s->img_file); -#endif - return s->img_buffer >= s->img_buffer_end; -} - -__forceinline static uint8 get8u(stbi *s) -{ - return (uint8) get8(s); -} - -static void skip(stbi *s, int n) -{ -#ifndef STBI_NO_STDIO - if (s->img_file) - fseek(s->img_file, n, SEEK_CUR); - else -#endif - s->img_buffer += n; -} - -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); -} - -static void getn(stbi *s, stbi_uc *buffer, int n) -{ -#ifndef STBI_NO_STDIO - if (s->img_file) { - fread(buffer, 1, n, s->img_file); - return; - } -#endif - memcpy(buffer, s->img_buffer, n); - s->img_buffer += n; -} - -////////////////////////////////////////////////////////////////////////////// -// -// 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] = 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] = 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 -{ - #if 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 = (j->code_buffer << 8) | b; - 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 -__forceinline 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 >> (j->code_bits - FAST_BITS)) & ((1 << FAST_BITS)-1); - k = h->fast[c]; - if (k < 255) { - if (h->size[k] > j->code_bits) - return -1; - j->code_bits -= h->size[k]; - 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. - if (j->code_bits < 16) - temp = (j->code_buffer << (16 - j->code_bits)) & 0xffff; - else - temp = (j->code_buffer >> (j->code_bits - 16)) & 0xffff; - 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 >> (j->code_bits - k)) & bmask[k]) + h->delta[k]; - assert((((j->code_buffer) >> (j->code_bits - h->size[c])) & bmask[h->size[c]]) == h->code[c]); - - // convert the id to a symbol - j->code_bits -= k; - return h->values[c]; -} - -// combined JPEG 'receive' and JPEG 'extend', since baseline -// always extends everything it receives. -__forceinline 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); - k = (j->code_buffer >> (j->code_bits - n)) & bmask[n]; - j->code_bits -= n; - // 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 -__forceinline static uint8 clamp(int x) -{ - x += 128; - // 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; - -#if !STBI_SIMD -// .344 seconds on 3*anemones.jpg -static void idct_block(uint8 *out, int out_stride, short data[64], uint8 *dequantize) -{ - int i,val[64],*v=val; - uint8 *o,*dq = dequantize; - 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. - x0 += 65536; x1 += 65536; x2 += 65536; x3 += 65536; - 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); - } -} -#else -static void idct_block(uint8 *out, int out_stride, short data[64], unsigned short *dequantize) -{ - int i,val[64],*v=val; - uint8 *o; - unsigned short *dq = dequantize; - 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. - x0 += 65536; x1 += 65536; x2 += 65536; x3 += 65536; - 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); - } -} -static stbi_idct_8x8 stbi_idct_installed = idct_block; - -extern 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; - #if 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; - #if 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; - #if 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); - #if 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; - } 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) -{ - 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; - 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]; - 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); - 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; - 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; - } -} - -#if 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) { - #if 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; - } -} - -#ifndef STBI_NO_STDIO -unsigned char *stbi_jpeg_load_from_file(FILE *f, int *x, int *y, int *comp, int req_comp) -{ - jpeg j; - start_file(&j.s, f); - return load_jpeg_image(&j, x,y,comp,req_comp); -} - -unsigned char *stbi_jpeg_load(char const *filename, int *x, int *y, int *comp, int req_comp) -{ - unsigned char *data; - FILE *f = fopen(filename, "rb"); - if (!f) return NULL; - data = stbi_jpeg_load_from_file(f,x,y,comp,req_comp); - fclose(f); - return data; -} -#endif - -unsigned char *stbi_jpeg_load_from_memory(stbi_uc const *buffer, int len, int *x, int *y, int *comp, int req_comp) -{ - jpeg j; - start_mem(&j.s, buffer,len); - return load_jpeg_image(&j, x,y,comp,req_comp); -} - -#ifndef STBI_NO_STDIO -int stbi_jpeg_test_file(FILE *f) -{ - int n,r; - jpeg j; - n = ftell(f); - start_file(&j.s, f); - r = decode_jpeg_header(&j, SCAN_type); - fseek(f,n,SEEK_SET); - return r; -} -#endif - -int stbi_jpeg_test_memory(stbi_uc const *buffer, int len) -{ - jpeg j; - start_mem(&j.s, buffer,len); - return decode_jpeg_header(&j, SCAN_type); -} - -// @TODO: -#ifndef STBI_NO_STDIO -extern int stbi_jpeg_info (char const *filename, int *x, int *y, int *comp); -extern int stbi_jpeg_info_from_file (FILE *f, int *x, int *y, int *comp); -#endif -extern int stbi_jpeg_info_from_memory(stbi_uc const *buffer, int len, int *x, int *y, int *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; - -__forceinline 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; -} - -__forceinline 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; - -__forceinline 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); -} - -__forceinline 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; -} - -__forceinline 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); -} - -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 (get8(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; - return 1; -} - -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; - stbi *s = &z->s; - - if (!check_png_header(s)) return 0; - - if (scan == SCAN_type) return 1; - - for(;;first=0) { - chunk c = get_chunk_header(s); - if (first && c.type != PNG_TYPE('I','H','D','R')) - return e("first not IHDR","Corrupt PNG"); - switch (c.type) { - case PNG_TYPE('I','H','D','R'): { - int depth,color,comp,filter; - if (!first) return e("multiple IHDR","Corrupt PNG"); - 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 (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 (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 (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; - } - #ifndef STBI_NO_STDIO - if (s->img_file) - { - if (fread(z->idata+ioff,1,c.length,s->img_file) != c.length) return e("outofdata","Corrupt PNG"); - } - else - #endif - { - memcpy(z->idata+ioff, s->img_buffer, c.length); - s->img_buffer += c.length; - } - ioff += c.length; - break; - } - - case PNG_TYPE('I','E','N','D'): { - uint32 raw_len; - if (scan != SCAN_load) return 1; - if (z->idata == NULL) return e("no IDAT","Corrupt PNG"); - z->expanded = (uint8 *) stbi_zlib_decode_malloc((char *) z->idata, ioff, (int *) &raw_len); - 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 (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 ((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; - p->expanded = NULL; - p->idata = NULL; - p->out = 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; -} - -#ifndef STBI_NO_STDIO -unsigned char *stbi_png_load_from_file(FILE *f, int *x, int *y, int *comp, int req_comp) -{ - png p; - start_file(&p.s, f); - return do_png(&p, x,y,comp,req_comp); -} - -unsigned char *stbi_png_load(char const *filename, int *x, int *y, int *comp, int req_comp) -{ - unsigned char *data; - FILE *f = fopen(filename, "rb"); - if (!f) return NULL; - data = stbi_png_load_from_file(f,x,y,comp,req_comp); - fclose(f); - return data; -} -#endif - -unsigned char *stbi_png_load_from_memory(stbi_uc const *buffer, int len, int *x, int *y, int *comp, int req_comp) -{ - png p; - start_mem(&p.s, buffer,len); - return do_png(&p, x,y,comp,req_comp); -} - -#ifndef STBI_NO_STDIO -int stbi_png_test_file(FILE *f) -{ - png p; - int n,r; - n = ftell(f); - start_file(&p.s, f); - r = parse_png_file(&p, SCAN_type,STBI_default); - fseek(f,n,SEEK_SET); - return r; -} -#endif - -int stbi_png_test_memory(stbi_uc const *buffer, int len) -{ - png p; - start_mem(&p.s, buffer, len); - return parse_png_file(&p, SCAN_type,STBI_default); -} - -// TODO: load header from png -#ifndef STBI_NO_STDIO -int stbi_png_info (char const *filename, int *x, int *y, int *comp) -{ - png p; - FILE *f = fopen(filename, "rb"); - if (!f) return 0; - start_file(&p.s, f); - if (parse_png_file(&p, SCAN_header, 0)) { - if(x) *x = p.s.img_x; - if(y) *y = p.s.img_y; - if (comp) *comp = p.s.img_n; - fclose(f); - return 1; - } - fclose(f); - return 0; -} - -extern int stbi_png_info_from_file (FILE *f, int *x, int *y, int *comp); -#endif -extern int stbi_png_info_from_memory (stbi_uc const *buffer, int len, int *x, int *y, int *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; -} - -#ifndef STBI_NO_STDIO -int stbi_bmp_test_file (FILE *f) -{ - stbi s; - int r,n = ftell(f); - start_file(&s,f); - r = bmp_test(&s); - fseek(f,n,SEEK_SET); - return r; -} -#endif - -int stbi_bmp_test_memory (stbi_uc const *buffer, int len) -{ - stbi s; - start_mem(&s, buffer, len); - return bmp_test(&s); -} - -// 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"); - failure_reason = "bad BMP"; - 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 0; - 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 = 0xff << 16; - mg = 0xff << 8; - mb = 0xff << 0; - ma = 0xff << 24; - fake_a = 1; // @TODO: check for cases like alpha value is all 0 and switch it to 255 - } else { - mr = 31 << 10; - mg = 31 << 5; - mb = 31 << 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 NULL; - } - } else - return NULL; - } - } 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] = get8(s); - pal[i][1] = get8(s); - pal[i][0] = get8(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 == 0xff000000 && ma == 0xff000000) - easy = 2; - } - if (!easy) { - if (!mr || !mg || !mb) 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] = get8(s); - out[z+1] = get8(s); - out[z+0] = get8(s); - z += 3; - a = (easy == 2 ? get8(s) : 255); - if (target == 4) out[z++] = a; - } - } else { - for (i=0; i < (int) s->img_x; ++i) { - uint32 v = (bpp == 16 ? get16le(s) : get32le(s)); - int a; - out[z++] = shiftsigned(v & mr, rshift, rcount); - out[z++] = shiftsigned(v & mg, gshift, gcount); - out[z++] = shiftsigned(v & mb, bshift, bcount); - a = (ma ? shiftsigned(v & ma, ashift, acount) : 255); - if (target == 4) out[z++] = 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 = target; - return out; -} - -#ifndef STBI_NO_STDIO -stbi_uc *stbi_bmp_load (char const *filename, int *x, int *y, int *comp, int req_comp) -{ - stbi_uc *data; - FILE *f = fopen(filename, "rb"); - if (!f) return NULL; - data = stbi_bmp_load_from_file(f, x,y,comp,req_comp); - fclose(f); - return data; -} - -stbi_uc *stbi_bmp_load_from_file (FILE *f, int *x, int *y, int *comp, int req_comp) -{ - stbi s; - start_file(&s, f); - return bmp_load(&s, x,y,comp,req_comp); -} -#endif - -stbi_uc *stbi_bmp_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 bmp_load(&s, x,y,comp,req_comp); -} - -// Targa Truevision - TGA -// by Jonathan Dummer - -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 -} - -#ifndef STBI_NO_STDIO -int stbi_tga_test_file (FILE *f) -{ - stbi s; - int r,n = ftell(f); - start_file(&s, f); - r = tga_test(&s); - fseek(f,n,SEEK_SET); - return r; -} -#endif - -int stbi_tga_test_memory (stbi_uc const *buffer, int len) -{ - stbi s; - start_mem(&s, buffer, len); - return tga_test(&s); -} - -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; - } - - // 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 ); - - // 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 ); - getn(s, tga_palette, tga_palette_len * tga_palette_bits / 8 ); - } - // 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 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; -} - -#ifndef STBI_NO_STDIO -stbi_uc *stbi_tga_load (char const *filename, int *x, int *y, int *comp, int req_comp) -{ - stbi_uc *data; - FILE *f = fopen(filename, "rb"); - if (!f) return NULL; - data = stbi_tga_load_from_file(f, x,y,comp,req_comp); - fclose(f); - return data; -} - -stbi_uc *stbi_tga_load_from_file (FILE *f, int *x, int *y, int *comp, int req_comp) -{ - stbi s; - start_file(&s, f); - return tga_load(&s, x,y,comp,req_comp); -} -#endif - -stbi_uc *stbi_tga_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 tga_load(&s, x,y,comp,req_comp); -} - - -// ************************************************************************************************* -// Photoshop PSD loader -- PD by Thatcher Ulrich, integration by Nicholas Schulz, tweaked by STB - -static int psd_test(stbi *s) -{ - if (get32(s) != 0x38425053) return 0; // "8BPS" - else return 1; -} - -#ifndef STBI_NO_STDIO -int stbi_psd_test_file(FILE *f) -{ - stbi s; - int r,n = ftell(f); - start_file(&s, f); - r = psd_test(&s); - fseek(f,n,SEEK_SET); - return r; -} -#endif - -int stbi_psd_test_memory(stbi_uc const *buffer, int len) -{ - stbi s; - start_mem(&s, buffer, len); - return psd_test(&s); -} - -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 = get8(s); - p += 4; - len--; - } - } else if (len > 128) { - uint32 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 = 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++) { - 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. - count = 0; - for (i = 0; i < pixelCount; i++) - *p = get8(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; -} - -#ifndef STBI_NO_STDIO -stbi_uc *stbi_psd_load(char const *filename, int *x, int *y, int *comp, int req_comp) -{ - stbi_uc *data; - FILE *f = fopen(filename, "rb"); - if (!f) return NULL; - data = stbi_psd_load_from_file(f, x,y,comp,req_comp); - fclose(f); - return data; -} - -stbi_uc *stbi_psd_load_from_file(FILE *f, int *x, int *y, int *comp, int req_comp) -{ - stbi s; - start_file(&s, f); - return psd_load(&s, x,y,comp,req_comp); -} -#endif - -stbi_uc *stbi_psd_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 psd_load(&s, x,y,comp,req_comp); -} - - -// ************************************************************************************************* -// Radiance RGBE HDR loader -// originally by Nicolas Schulz -#ifndef STBI_NO_HDR -static int hdr_test(stbi *s) -{ - char *signature = "#?RADIANCE\n"; - int i; - for (i=0; signature[i]; ++i) - if (get8(s) != signature[i]) - return 0; - return 1; -} - -int stbi_hdr_test_memory(stbi_uc const *buffer, int len) -{ - stbi s; - start_mem(&s, buffer, len); - return hdr_test(&s); -} - -#ifndef STBI_NO_STDIO -int stbi_hdr_test_file(FILE *f) -{ - stbi s; - int r,n = ftell(f); - start_file(&s, f); - r = hdr_test(&s); - fseek(f,n,SEEK_SET); - return r; -} -#endif - -#define HDR_BUFLEN 1024 -static char *hdr_gettoken(stbi *z, char *buffer) -{ - int len=0; - char *s = buffer, c = '\0'; - - c = 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 = 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 - while(1) { - 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) - stbi_uc rgbe[4] = { c1,c2,len, get8(s) }; - hdr_convert(hdr_data, rgbe, req_comp); - i = 1; - j = 0; - free(scanline); - goto main_decode_loop; // yes, this is fucking insane; blame the fucking insane format - } - 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 = get8(s); - if (count > 128) { - // Run - value = 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] = get8(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; -} - -#ifndef STBI_NO_STDIO -float *stbi_hdr_load_from_file(FILE *f, int *x, int *y, int *comp, int req_comp) -{ - stbi s; - start_file(&s,f); - return hdr_load(&s,x,y,comp,req_comp); -} -#endif - -float *stbi_hdr_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 hdr_load(&s,x,y,comp,req_comp); -} - -#endif // STBI_NO_HDR - -/////////////////////// write image /////////////////////// - -#ifndef STBI_NO_WRITE - -static void write8(FILE *f, int x) { uint8 z = (uint8) x; fwrite(&z,1,1,f); } - -static void writefv(FILE *f, char *fmt, va_list v) -{ - while (*fmt) { - switch (*fmt++) { - case ' ': break; - case '1': { uint8 x = va_arg(v, int); write8(f,x); break; } - case '2': { int16 x = va_arg(v, int); write8(f,x); write8(f,x>>8); break; } - case '4': { int32 x = va_arg(v, int); write8(f,x); write8(f,x>>8); write8(f,x>>16); write8(f,x>>24); break; } - default: - assert(0); - va_end(v); - return; - } - } -} - -static void writef(FILE *f, char *fmt, ...) -{ - va_list v; - va_start(v, fmt); - writefv(f,fmt,v); - va_end(v); -} - -static void write_pixels(FILE *f, int rgb_dir, int vdir, int x, int y, int comp, void *data, int write_alpha, int scanline_pad) -{ - uint8 bg[3] = { 255, 0, 255}, px[3]; - uint32 zero = 0; - int i,j,k, j_end; - - if (vdir < 0) - j_end = -1, j = y-1; - else - j_end = y, j = 0; - - for (; j != j_end; j += vdir) { - for (i=0; i < x; ++i) { - uint8 *d = (uint8 *) data + (j*x+i)*comp; - if (write_alpha < 0) - fwrite(&d[comp-1], 1, 1, f); - switch (comp) { - case 1: - case 2: writef(f, "111", d[0],d[0],d[0]); - break; - case 4: - if (!write_alpha) { - for (k=0; k < 3; ++k) - px[k] = bg[k] + ((d[k] - bg[k]) * d[3])/255; - writef(f, "111", px[1-rgb_dir],px[1],px[1+rgb_dir]); - break; - } - /* FALLTHROUGH */ - case 3: - writef(f, "111", d[1-rgb_dir],d[1],d[1+rgb_dir]); - break; - } - if (write_alpha > 0) - fwrite(&d[comp-1], 1, 1, f); - } - fwrite(&zero,scanline_pad,1,f); - } -} - -static int outfile(char const *filename, int rgb_dir, int vdir, int x, int y, int comp, void *data, int alpha, int pad, char *fmt, ...) -{ - FILE *f = fopen(filename, "wb"); - if (f) { - va_list v; - va_start(v, fmt); - writefv(f, fmt, v); - va_end(v); - write_pixels(f,rgb_dir,vdir,x,y,comp,data,alpha,pad); - fclose(f); - } - return f != NULL; -} - -int stbi_write_bmp(char const *filename, int x, int y, int comp, void *data) -{ - int pad = (-x*3) & 3; - return outfile(filename,-1,-1,x,y,comp,data,0,pad, - "11 4 22 4" "4 44 22 444444", - 'B', 'M', 14+40+(x*3+pad)*y, 0,0, 14+40, // file header - 40, x,y, 1,24, 0,0,0,0,0,0); // bitmap header -} - -int stbi_write_tga(char const *filename, int x, int y, int comp, void *data) -{ - int has_alpha = !(comp & 1); - return outfile(filename, -1,-1, x, y, comp, data, has_alpha, 0, - "111 221 2222 11", 0,0,2, 0,0,0, 0,0,x,y, 24+8*has_alpha, 8*has_alpha); -} - -// any other image formats that do interleaved rgb data? -// PNG: requires adler32,crc32 -- significant amount of code -// PSD: no, channels output separately -// TIFF: no, stripwise-interleaved... i think - -#endif // STBI_NO_WRITE - -#endif // STBI_HEADER_FILE_ONLY - +/* 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 + 1.28 (2010-08-01) fix bug in GIF palette transparency (SpartanJ) + 1.27 (2010-08-01) cast-to-uint8 to fix warnings (Laurent Gomila) + allow trailing 0s at end of image data (Laurent Gomila) + 1.26 (2010-07-24) fix bug in file buffering for PNG reported by SpartanJ + + 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_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 //////////////////////////////////////////////////// +// +// 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 1-bit BMP +// - GIF always returns *comp=4 +// +// Basic usage (see HDR discussion below): +// int x,y,n; +// unsigned char *data = stbi_load(filename, &x, &y, &n, 0); +// // ... 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 +// stbi_image_free(data) +// +// Standard parameters: +// int *x -- outputs image width in pixels +// int *y -- outputs image height in pixels +// int *comp -- outputs # of image components in image file +// 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, +// 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. +// +// An output image with N components has the following components interleaved +// in this order in each pixel: +// +// N=#comp components +// 1 grey +// 2 grey, alpha +// 3 red, green, blue +// 4 red, green, blue, alpha +// +// If image loading fails for any reason, the return value will be NULL, +// and *x, *y, *comp will be unchanged. The function stbi_failure_reason() +// can be queried for an extremely brief, end-user unfriendly explanation +// of why the load failed. Define STBI_NO_FAILURE_STRINGS to avoid +// compiling these strings at all, and STBI_FAILURE_USERMSG to get slightly +// more user-friendly ones. +// +// Paletted PNG, BMP, GIF, and PIC images are automatically depalettized. +// +// =========================================================================== +// +// iPhone PNG support: +// +// 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. +// +// 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). +// +// =========================================================================== +// +// HDR image support (disable by defining STBI_NO_HDR) +// +// stb_image now supports loading HDR images in general, and currently +// the Radiance .HDR file format, although the support is provided +// generically. You can still load any file through the existing interface; +// if you attempt to load an HDR file, it will be automatically remapped to +// LDR, assuming gamma 2.2 and an arbitrary scale factor defaulting to 1; +// both of these constants can be reconfigured through this interface: +// +// stbi_hdr_to_ldr_gamma(2.2f); +// stbi_hdr_to_ldr_scale(1.0f); +// +// (note, do not use _inverse_ constants; stbi_image will invert them +// appropriately). +// +// Additionally, there is a new, parallel interface for loading files as +// (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: +// +// stbi_ldr_to_hdr_scale(1.0f); +// stbi_ldr_to_hdr_gamma(2.2f); +// +// Finally, given a filename (or an open file or memory block--see header +// file for details) containing image data, you can query for the "most +// appropriate" interface to use (that is, whether the image is HDR or +// not), using: +// +// stbi_is_hdr(char *filename); +// +// =========================================================================== +// +// 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). + + +#ifndef STBI_NO_STDIO + +#if defined(_MSC_VER) && _MSC_VER >= 0x1400 +#define _CRT_SECURE_NO_WARNINGS // suppress bogus warnings about fopen() +#endif + +#include +#endif + +#define STBI_VERSION 1 + +enum +{ + STBI_default = 0, // only used for req_comp + + STBI_grey = 1, + STBI_grey_alpha = 2, + STBI_rgb = 3, + STBI_rgb_alpha = 4 +}; + +typedef unsigned char stbi_uc; + +#ifdef __cplusplus +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 +#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; + +extern 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_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); +#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_STDIO +extern int stbi_is_hdr (char const *filename); +extern 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); + +// free the loaded image -- this is just free() +extern 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); + +#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); + +#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); + +// 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); + + +// 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); + +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 + + +#ifdef __cplusplus +} +#endif + +// +// +//// end header file ///////////////////////////////////////////////////// +#endif // STBI_INCLUDE_STB_IMAGE_H + +#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; + in_far = 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: + 1.33 (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/example/viewer.hs b/example/viewer.hs --- a/example/viewer.hs +++ b/example/viewer.hs @@ -8,10 +8,10 @@ import Data.Bits -import Graphics.Rendering.OpenGL -import Graphics.UI.GLUT +import Graphics.Rendering.OpenGL.GL +import Graphics.UI.GLUT -import Data.Bitmap.IO +import Data.Bitmap.Pure import Data.Bitmap.OpenGL import Codec.Image.STB @@ -47,7 +47,7 @@ createWindow ("viewer - " ++ show fname) - eimg <- extendImage img + let eimg = extendImage img tex <- makeSimpleBitmapTexture eimg displayCallback $= display img tex @@ -116,11 +116,10 @@ nextPowerOfTwo n = 2 ^ ( 1 + log2 (n-1) ) -- extend the image to have power-of-two sizes, for old videocards -extendImage :: Image -> IO Image -extendImage bm = do - let (oldx,oldy) = bitmapSize bm - (newx,newy) = (nextPowerOfTwo oldx, nextPowerOfTwo newx) - copySubImage' bm (0,0) (oldx,oldy) (newx,newy) (0,0) +extendImage :: Image -> Image +extendImage bm = copySubImage' bm (0,0) (oldx,oldy) (newx,newy) (0,0) where + (oldx,oldy) = bitmapSize bm + (newx,newy) = (nextPowerOfTwo oldx, nextPowerOfTwo newx) -------------------------------------------------------------------------------- diff --git a/stb-image.cabal b/stb-image.cabal --- a/stb-image.cabal +++ b/stb-image.cabal @@ -1,5 +1,5 @@ Name: stb-image -Version: 0.2 +Version: 0.2.1 Synopsis: A wrapper around Sean Barrett's JPEG/PNG decoder Description: Partial implementation of JPEG, PNG, TGA, BMP, PSD decoders, with a really simple API. @@ -10,32 +10,26 @@ Homepage: http://code.haskell.org/~bkomuves/ Stability: Experimental Category: Codec, Graphics -Tested-With: GHC == 6.10.1, GHC == 6.8.3 +Tested-With: GHC == 6.12.3 Cabal-Version: >= 1.2 Build-Type: Simple Extra-Source-Files: example/viewer.hs, cbits/stb_image.h -Flag splitBase - Description: Choose the new smaller, split-up base package. - Flag base4 Description: Base-4 uses new exception framework Library - if flag(splitBase) - Build-Depends: bytestring >= 0.9, - bitmap < 0.1 - if flag(base4) - Build-Depends: base >= 4 && < 5 - cpp-options: -DBASE_MAJOR_VERSION=4 - else - Build-Depends: base >= 3 && < 4 - cpp-options: -DBASE_MAJOR_VERSION=3 + Build-Depends: bytestring >= 0.9, + bitmap >= 0.0.2 && < 0.1 + + if flag(base4) + Build-Depends: base >= 4 && < 5 + cpp-options: -DBASE_MAJOR_VERSION=4 else - Build-Depends: base < 3 - cpp-options: -DBASE_MAJOR_VERSION=2 + Build-Depends: base >= 3 && < 4 + cpp-options: -DBASE_MAJOR_VERSION=3 Exposed-Modules: Codec.Image.STB