stb_image.c revision 1.2
1/* stbi-1.29 - public domain JPEG/PNG reader - http://nothings.org/stb_image.c 2 when you control the images you're loading 3 no warranty implied; use at your own risk 4 5 QUICK NOTES: 6 Primarily of interest to game developers and other people who can 7 avoid problematic images and only need the trivial interface 8 9 JPEG baseline (no JPEG progressive) 10 PNG 8-bit only 11 12 TGA (not sure what subset, if a subset) 13 BMP non-1bpp, non-RLE 14 PSD (composited view only, no extra channels) 15 16 GIF (*comp always reports as 4-channel) 17 HDR (radiance rgbE format) 18 PIC (Softimage PIC) 19 20 - decoded from memory or through stdio FILE (define STBI_NO_STDIO to remove code) 21 - supports installable dequantizing-IDCT, YCbCr-to-RGB conversion (define STBI_SIMD) 22 23 Latest revisions: 24 1.29 (2010-08-16) various warning fixes from Aurelien Pocheville 25 1.28 (2010-08-01) fix bug in GIF palette transparency (SpartanJ) 26 1.27 (2010-08-01) cast-to-uint8 to fix warnings (Laurent Gomila) 27 allow trailing 0s at end of image data (Laurent Gomila) 28 1.26 (2010-07-24) fix bug in file buffering for PNG reported by SpartanJ 29 1.25 (2010-07-17) refix trans_data warning (Won Chun) 30 1.24 (2010-07-12) perf improvements reading from files 31 minor perf improvements for jpeg 32 deprecated type-specific functions in hope of feedback 33 attempt to fix trans_data warning (Won Chun) 34 1.23 fixed bug in iPhone support 35 1.22 (2010-07-10) removed image *writing* support to stb_image_write.h 36 stbi_info support from Jetro Lauha 37 GIF support from Jean-Marc Lienher 38 iPhone PNG-extensions from James Brown 39 warning-fixes from Nicolas Schulz and Janez Zemva 40 1.21 fix use of 'uint8' in header (reported by jon blow) 41 1.20 added support for Softimage PIC, by Tom Seddon 42 43 See end of file for full revision history. 44 45 TODO: 46 stbi_info support for BMP,PSD,HDR,PIC 47 rewrite stbi_info and load_file variations to share file handling code 48 (current system allows individual functions to be called directly, 49 since each does all the work, but I doubt anyone uses this in practice) 50 51 52 ============================ Contributors ========================= 53 54 Image formats Optimizations & bugfixes 55 Sean Barrett (jpeg, png, bmp) Fabian "ryg" Giesen 56 Nicolas Schulz (hdr, psd) 57 Jonathan Dummer (tga) Bug fixes & warning fixes 58 Jean-Marc Lienher (gif) Marc LeBlanc 59 Tom Seddon (pic) Christpher Lloyd 60 Thatcher Ulrich (psd) Dave Moore 61 Won Chun 62 the Horde3D community 63 Extensions, features Janez Zemva 64 Jetro Lauha (stbi_info) Jonathan Blow 65 James "moose2000" Brown (iPhone PNG) Laurent Gomila 66 Aruelien Pocheville 67 68 If your name should be here but isn't, let Sean know. 69 70*/ 71 72#ifdef _KERNEL 73#include <dev/stbi/stbiconfig.h> 74#endif 75 76#ifndef STBI_INCLUDE_STB_IMAGE_H 77#define STBI_INCLUDE_STB_IMAGE_H 78 79// To get a header file for this, either cut and paste the header, 80// or create stb_image.h, #define STBI_HEADER_FILE_ONLY, and 81// then include stb_image.c from it. 82 83//// begin header file //////////////////////////////////////////////////// 84// 85// Limitations: 86// - no jpeg progressive support 87// - non-HDR formats support 8-bit samples only (jpeg, png) 88// - no delayed line count (jpeg) -- IJG doesn't support either 89// - no 1-bit BMP 90// - GIF always returns *comp=4 91// 92// Basic usage (see HDR discussion below): 93// int x,y,n; 94// unsigned char *data = stbi_load(filename, &x, &y, &n, 0); 95// // ... process data if not NULL ... 96// // ... x = width, y = height, n = # 8-bit components per pixel ... 97// // ... replace '0' with '1'..'4' to force that many components per pixel 98// stbi_image_free(data) 99// 100// Standard parameters: 101// int *x -- outputs image width in pixels 102// int *y -- outputs image height in pixels 103// int *comp -- outputs # of image components in image file 104// int req_comp -- if non-zero, # of image components requested in result 105// 106// The return value from an image loader is an 'unsigned char *' which points 107// to the pixel data. The pixel data consists of *y scanlines of *x pixels, 108// with each pixel consisting of N interleaved 8-bit components; the first 109// pixel pointed to is top-left-most in the image. There is no padding between 110// image scanlines or between pixels, regardless of format. The number of 111// components N is 'req_comp' if req_comp is non-zero, or *comp otherwise. 112// If req_comp is non-zero, *comp has the number of components that _would_ 113// have been output otherwise. E.g. if you set req_comp to 4, you will always 114// get RGBA output, but you can check *comp to easily see if it's opaque. 115// 116// An output image with N components has the following components interleaved 117// in this order in each pixel: 118// 119// N=#comp components 120// 1 grey 121// 2 grey, alpha 122// 3 red, green, blue 123// 4 red, green, blue, alpha 124// 125// If image loading fails for any reason, the return value will be NULL, 126// and *x, *y, *comp will be unchanged. The function stbi_failure_reason() 127// can be queried for an extremely brief, end-user unfriendly explanation 128// of why the load failed. Define STBI_NO_FAILURE_STRINGS to avoid 129// compiling these strings at all, and STBI_FAILURE_USERMSG to get slightly 130// more user-friendly ones. 131// 132// Paletted PNG, BMP, GIF, and PIC images are automatically depalettized. 133// 134// =========================================================================== 135// 136// iPhone PNG support: 137// 138// By default we convert iphone-formatted PNGs back to RGB; nominally they 139// would silently load as BGR, except the existing code should have just 140// failed on such iPhone PNGs. But you can disable this conversion by 141// by calling stbi_convert_iphone_png_to_rgb(0), in which case 142// you will always just get the native iphone "format" through. 143// 144// Call stbi_set_unpremultiply_on_load(1) as well to force a divide per 145// pixel to remove any premultiplied alpha *only* if the image file explicitly 146// says there's premultiplied data (currently only happens in iPhone images, 147// and only if iPhone convert-to-rgb processing is on). 148// 149// =========================================================================== 150// 151// HDR image support (disable by defining STBI_NO_HDR) 152// 153// stb_image now supports loading HDR images in general, and currently 154// the Radiance .HDR file format, although the support is provided 155// generically. You can still load any file through the existing interface; 156// if you attempt to load an HDR file, it will be automatically remapped to 157// LDR, assuming gamma 2.2 and an arbitrary scale factor defaulting to 1; 158// both of these constants can be reconfigured through this interface: 159// 160// stbi_hdr_to_ldr_gamma(2.2f); 161// stbi_hdr_to_ldr_scale(1.0f); 162// 163// (note, do not use _inverse_ constants; stbi_image will invert them 164// appropriately). 165// 166// Additionally, there is a new, parallel interface for loading files as 167// (linear) floats to preserve the full dynamic range: 168// 169// float *data = stbi_loadf(filename, &x, &y, &n, 0); 170// 171// If you load LDR images through this interface, those images will 172// be promoted to floating point values, run through the inverse of 173// constants corresponding to the above: 174// 175// stbi_ldr_to_hdr_scale(1.0f); 176// stbi_ldr_to_hdr_gamma(2.2f); 177// 178// Finally, given a filename (or an open file or memory block--see header 179// file for details) containing image data, you can query for the "most 180// appropriate" interface to use (that is, whether the image is HDR or 181// not), using: 182// 183// stbi_is_hdr(char *filename); 184 185#ifndef STBI_NO_STDIO 186#include <stdio.h> 187#endif 188 189#define STBI_VERSION 1 190 191enum 192{ 193 STBI_default = 0, // only used for req_comp 194 195 STBI_grey = 1, 196 STBI_grey_alpha = 2, 197 STBI_rgb = 3, 198 STBI_rgb_alpha = 4 199}; 200 201typedef unsigned char stbi_uc; 202 203#ifdef __cplusplus 204extern "C" { 205#endif 206 207// PRIMARY API - works on images of any type 208 209// load image by filename, open file, or memory buffer 210extern stbi_uc *stbi_load_from_memory(stbi_uc const *buffer, int len, int *x, int *y, int *comp, int req_comp); 211 212#ifndef STBI_NO_STDIO 213extern stbi_uc *stbi_load (char const *filename, int *x, int *y, int *comp, int req_comp); 214extern stbi_uc *stbi_load_from_file (FILE *f, int *x, int *y, int *comp, int req_comp); 215// for stbi_load_from_file, file pointer is left pointing immediately after image 216#endif 217 218#ifndef STBI_NO_HDR 219 extern float *stbi_loadf_from_memory(stbi_uc const *buffer, int len, int *x, int *y, int *comp, int req_comp); 220 221 #ifndef STBI_NO_STDIO 222 extern float *stbi_loadf (char const *filename, int *x, int *y, int *comp, int req_comp); 223 extern float *stbi_loadf_from_file (FILE *f, int *x, int *y, int *comp, int req_comp); 224 #endif 225 226 extern void stbi_hdr_to_ldr_gamma(float gamma); 227 extern void stbi_hdr_to_ldr_scale(float scale); 228 229 extern void stbi_ldr_to_hdr_gamma(float gamma); 230 extern void stbi_ldr_to_hdr_scale(float scale); 231#endif // STBI_NO_HDR 232 233// get a VERY brief reason for failure 234// NOT THREADSAFE 235extern const char *stbi_failure_reason (void); 236 237// free the loaded image -- this is just free() 238extern void stbi_image_free (void *retval_from_stbi_load); 239 240// get image dimensions & components without fully decoding 241extern int stbi_info_from_memory(stbi_uc const *buffer, int len, int *x, int *y, int *comp); 242extern int stbi_is_hdr_from_memory(stbi_uc const *buffer, int len); 243 244#ifndef STBI_NO_STDIO 245extern int stbi_info (char const *filename, int *x, int *y, int *comp); 246extern int stbi_info_from_file (FILE *f, int *x, int *y, int *comp); 247 248extern int stbi_is_hdr (char const *filename); 249extern int stbi_is_hdr_from_file(FILE *f); 250#endif 251 252// for image formats that explicitly notate that they have premultiplied alpha, 253// we just return the colors as stored in the file. set this flag to force 254// unpremultiplication. results are undefined if the unpremultiply overflow. 255extern void stbi_set_unpremultiply_on_load(int flag_true_if_should_unpremultiply); 256 257// indicate whether we should process iphone images back to canonical format, 258// or just pass them through "as-is" 259extern void stbi_convert_iphone_png_to_rgb(int flag_true_if_should_convert); 260 261 262// ZLIB client - used by PNG, available for other purposes 263 264extern char *stbi_zlib_decode_malloc_guesssize(const char *buffer, int len, int initial_size, int *outlen); 265extern char *stbi_zlib_decode_malloc_guesssize_headerflag(const char *buffer, int len, int initial_size, int *outlen, int parse_header); 266extern char *stbi_zlib_decode_malloc(const char *buffer, int len, int *outlen); 267extern int stbi_zlib_decode_buffer(char *obuffer, int olen, const char *ibuffer, int ilen); 268 269extern char *stbi_zlib_decode_noheader_malloc(const char *buffer, int len, int *outlen); 270extern int stbi_zlib_decode_noheader_buffer(char *obuffer, int olen, const char *ibuffer, int ilen); 271 272// define new loaders 273typedef struct 274{ 275 int (*test_memory)(stbi_uc const *buffer, int len); 276 stbi_uc * (*load_from_memory)(stbi_uc const *buffer, int len, int *x, int *y, int *comp, int req_comp); 277 #ifndef STBI_NO_STDIO 278 int (*test_file)(FILE *f); 279 stbi_uc * (*load_from_file)(FILE *f, int *x, int *y, int *comp, int req_comp); 280 #endif 281} stbi_loader; 282 283// register a loader by filling out the above structure (you must define ALL functions) 284// returns 1 if added or already added, 0 if not added (too many loaders) 285// NOT THREADSAFE 286extern int stbi_register_loader(stbi_loader *loader); 287 288// define faster low-level operations (typically SIMD support) 289#ifdef STBI_SIMD 290typedef void (*stbi_idct_8x8)(stbi_uc *out, int out_stride, short data[64], unsigned short *dequantize); 291// compute an integer IDCT on "input" 292// input[x] = data[x] * dequantize[x] 293// write results to 'out': 64 samples, each run of 8 spaced by 'out_stride' 294// CLAMP results to 0..255 295typedef 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); 296// compute a conversion from YCbCr to RGB 297// 'count' pixels 298// write pixels to 'output'; each pixel is 'step' bytes (either 3 or 4; if 4, write '255' as 4th), order R,G,B 299// y: Y input channel 300// cb: Cb input channel; scale/biased to be 0..255 301// cr: Cr input channel; scale/biased to be 0..255 302 303extern void stbi_install_idct(stbi_idct_8x8 func); 304extern void stbi_install_YCbCr_to_RGB(stbi_YCbCr_to_RGB_run func); 305#endif // STBI_SIMD 306 307 308 309 310// TYPE-SPECIFIC ACCESS 311 312#ifdef STBI_TYPE_SPECIFIC_FUNCTIONS 313 314// is it a jpeg? 315extern int stbi_jpeg_test_memory (stbi_uc const *buffer, int len); 316extern stbi_uc *stbi_jpeg_load_from_memory(stbi_uc const *buffer, int len, int *x, int *y, int *comp, int req_comp); 317extern int stbi_jpeg_info_from_memory(stbi_uc const *buffer, int len, int *x, int *y, int *comp); 318 319#ifndef STBI_NO_STDIO 320extern stbi_uc *stbi_jpeg_load (char const *filename, int *x, int *y, int *comp, int req_comp); 321extern int stbi_jpeg_test_file (FILE *f); 322extern stbi_uc *stbi_jpeg_load_from_file (FILE *f, int *x, int *y, int *comp, int req_comp); 323 324extern int stbi_jpeg_info (char const *filename, int *x, int *y, int *comp); 325extern int stbi_jpeg_info_from_file (FILE *f, int *x, int *y, int *comp); 326#endif 327 328// is it a png? 329extern int stbi_png_test_memory (stbi_uc const *buffer, int len); 330extern stbi_uc *stbi_png_load_from_memory (stbi_uc const *buffer, int len, int *x, int *y, int *comp, int req_comp); 331extern int stbi_png_info_from_memory (stbi_uc const *buffer, int len, int *x, int *y, int *comp); 332 333#ifndef STBI_NO_STDIO 334extern stbi_uc *stbi_png_load (char const *filename, int *x, int *y, int *comp, int req_comp); 335extern int stbi_png_info (char const *filename, int *x, int *y, int *comp); 336extern int stbi_png_test_file (FILE *f); 337extern stbi_uc *stbi_png_load_from_file (FILE *f, int *x, int *y, int *comp, int req_comp); 338extern int stbi_png_info_from_file (FILE *f, int *x, int *y, int *comp); 339#endif 340 341// is it a bmp? 342extern int stbi_bmp_test_memory (stbi_uc const *buffer, int len); 343 344extern stbi_uc *stbi_bmp_load (char const *filename, int *x, int *y, int *comp, int req_comp); 345extern stbi_uc *stbi_bmp_load_from_memory (stbi_uc const *buffer, int len, int *x, int *y, int *comp, int req_comp); 346#ifndef STBI_NO_STDIO 347extern int stbi_bmp_test_file (FILE *f); 348extern stbi_uc *stbi_bmp_load_from_file (FILE *f, int *x, int *y, int *comp, int req_comp); 349#endif 350 351// is it a tga? 352extern int stbi_tga_test_memory (stbi_uc const *buffer, int len); 353 354extern stbi_uc *stbi_tga_load (char const *filename, int *x, int *y, int *comp, int req_comp); 355extern stbi_uc *stbi_tga_load_from_memory (stbi_uc const *buffer, int len, int *x, int *y, int *comp, int req_comp); 356extern int stbi_tga_info_from_memory (stbi_uc const *buffer, int len, int *x, int *y, int *comp); 357#ifndef STBI_NO_STDIO 358extern int stbi_tga_info_from_file (FILE *f, int *x, int *y, int *comp); 359extern int stbi_tga_test_file (FILE *f); 360extern stbi_uc *stbi_tga_load_from_file (FILE *f, int *x, int *y, int *comp, int req_comp); 361#endif 362 363// is it a psd? 364extern int stbi_psd_test_memory (stbi_uc const *buffer, int len); 365 366extern stbi_uc *stbi_psd_load (char const *filename, int *x, int *y, int *comp, int req_comp); 367extern stbi_uc *stbi_psd_load_from_memory (stbi_uc const *buffer, int len, int *x, int *y, int *comp, int req_comp); 368#ifndef STBI_NO_STDIO 369extern int stbi_psd_test_file (FILE *f); 370extern stbi_uc *stbi_psd_load_from_file (FILE *f, int *x, int *y, int *comp, int req_comp); 371#endif 372 373// is it an hdr? 374extern int stbi_hdr_test_memory (stbi_uc const *buffer, int len); 375 376extern float * stbi_hdr_load (char const *filename, int *x, int *y, int *comp, int req_comp); 377extern float * stbi_hdr_load_from_memory (stbi_uc const *buffer, int len, int *x, int *y, int *comp, int req_comp); 378#ifndef STBI_NO_STDIO 379extern int stbi_hdr_test_file (FILE *f); 380extern float * stbi_hdr_load_from_file (FILE *f, int *x, int *y, int *comp, int req_comp); 381#endif 382 383// is it a pic? 384extern int stbi_pic_test_memory (stbi_uc const *buffer, int len); 385 386extern stbi_uc *stbi_pic_load (char const *filename, int *x, int *y, int *comp, int req_comp); 387extern stbi_uc *stbi_pic_load_from_memory (stbi_uc const *buffer, int len, int *x, int *y, int *comp, int req_comp); 388#ifndef STBI_NO_STDIO 389extern int stbi_pic_test_file (FILE *f); 390extern stbi_uc *stbi_pic_load_from_file (FILE *f, int *x, int *y, int *comp, int req_comp); 391#endif 392 393// is it a gif? 394extern int stbi_gif_test_memory (stbi_uc const *buffer, int len); 395 396extern stbi_uc *stbi_gif_load (char const *filename, int *x, int *y, int *comp, int req_comp); 397extern stbi_uc *stbi_gif_load_from_memory (stbi_uc const *buffer, int len, int *x, int *y, int *comp, int req_comp); 398extern int stbi_gif_info_from_memory (stbi_uc const *buffer, int len, int *x, int *y, int *comp); 399 400#ifndef STBI_NO_STDIO 401extern int stbi_gif_test_file (FILE *f); 402extern stbi_uc *stbi_gif_load_from_file (FILE *f, int *x, int *y, int *comp, int req_comp); 403extern int stbi_gif_info (char const *filename, int *x, int *y, int *comp); 404extern int stbi_gif_info_from_file (FILE *f, int *x, int *y, int *comp); 405#endif 406 407#endif//STBI_TYPE_SPECIFIC_FUNCTIONS 408 409 410 411 412#ifdef __cplusplus 413} 414#endif 415 416// 417// 418//// end header file ///////////////////////////////////////////////////// 419#endif // STBI_INCLUDE_STB_IMAGE_H 420 421#ifndef STBI_HEADER_FILE_ONLY 422 423#ifndef STBI_NO_HDR 424#include <math.h> // ldexp 425#include <string.h> // strcmp 426#endif 427 428#ifndef STBI_NO_STDIO 429#include <stdio.h> 430#endif 431#ifdef _KERNEL 432#include <sys/cdefs.h> 433__KERNEL_RCSID(0, "$NetBSD: stb_image.c,v 1.2 2012/01/20 23:13:47 jmcneill Exp $"); 434#include <sys/param.h> 435#include <sys/systm.h> 436#include <sys/kernel.h> 437#include <sys/types.h> 438#include <sys/malloc.h> 439#else 440#include <stdlib.h> 441#include <memory.h> 442#include <assert.h> 443#include <stdarg.h> 444#endif 445 446#ifdef _KERNEL 447#define MALLOC(size) malloc((size), M_TEMP, M_WAITOK) 448#define REALLOC(ptr, size) realloc((ptr), (size), M_TEMP, M_WAITOK) 449#define FREE(ptr) free((ptr), M_TEMP) 450#else 451#define MALLOC(size) malloc((size)) 452#define REALLOC(ptr, size) realloc((ptr), (size)) 453#define FREE(ptr) free((ptr)) 454#endif 455 456#ifndef _MSC_VER 457 #ifdef __cplusplus 458 #define __forceinline inline 459 #else 460 #define __forceinline 461 #endif 462#endif 463 464 465// implementation: 466typedef unsigned char uint8; 467typedef unsigned short uint16; 468typedef signed short int16; 469typedef unsigned int uint32; 470typedef signed int int32; 471#ifndef __NetBSD__ 472typedef unsigned int uint; 473#endif 474 475// should produce compiler error if size is wrong 476typedef unsigned char validate_uint32[sizeof(uint32)==4 ? 1 : -1]; 477 478#if defined(STBI_NO_STDIO) && !defined(STBI_NO_WRITE) 479#define STBI_NO_WRITE 480#endif 481 482#define STBI_NOTUSED(v) v=v 483 484#ifdef _MSC_VER 485#define STBI_HAS_LRTOL 486#endif 487 488#ifdef STBI_HAS_LRTOL 489 #define stbi_lrot(x,y) _lrotl(x,y) 490#else 491 #define stbi_lrot(x,y) (((x) << (y)) | ((x) >> (32 - (y)))) 492#endif 493 494////////////////////////////////////////////////////////////////////////////// 495// 496// Generic API that works on all image types 497// 498 499// deprecated functions 500 501// is it a jpeg? 502extern int stbi_jpeg_test_memory (stbi_uc const *buffer, int len); 503extern stbi_uc *stbi_jpeg_load_from_memory(stbi_uc const *buffer, int len, int *x, int *y, int *comp, int req_comp); 504extern int stbi_jpeg_info_from_memory(stbi_uc const *buffer, int len, int *x, int *y, int *comp); 505 506#ifndef STBI_NO_STDIO 507extern stbi_uc *stbi_jpeg_load (char const *filename, int *x, int *y, int *comp, int req_comp); 508extern int stbi_jpeg_test_file (FILE *f); 509extern stbi_uc *stbi_jpeg_load_from_file (FILE *f, int *x, int *y, int *comp, int req_comp); 510 511extern int stbi_jpeg_info (char const *filename, int *x, int *y, int *comp); 512extern int stbi_jpeg_info_from_file (FILE *f, int *x, int *y, int *comp); 513#endif 514 515// is it a png? 516extern int stbi_png_test_memory (stbi_uc const *buffer, int len); 517extern stbi_uc *stbi_png_load_from_memory (stbi_uc const *buffer, int len, int *x, int *y, int *comp, int req_comp); 518extern int stbi_png_info_from_memory (stbi_uc const *buffer, int len, int *x, int *y, int *comp); 519 520#ifndef STBI_NO_STDIO 521extern stbi_uc *stbi_png_load (char const *filename, int *x, int *y, int *comp, int req_comp); 522extern int stbi_png_info (char const *filename, int *x, int *y, int *comp); 523extern int stbi_png_test_file (FILE *f); 524extern stbi_uc *stbi_png_load_from_file (FILE *f, int *x, int *y, int *comp, int req_comp); 525extern int stbi_png_info_from_file (FILE *f, int *x, int *y, int *comp); 526#endif 527 528// is it a bmp? 529extern int stbi_bmp_test_memory (stbi_uc const *buffer, int len); 530 531extern stbi_uc *stbi_bmp_load (char const *filename, int *x, int *y, int *comp, int req_comp); 532extern stbi_uc *stbi_bmp_load_from_memory (stbi_uc const *buffer, int len, int *x, int *y, int *comp, int req_comp); 533#ifndef STBI_NO_STDIO 534extern int stbi_bmp_test_file (FILE *f); 535extern stbi_uc *stbi_bmp_load_from_file (FILE *f, int *x, int *y, int *comp, int req_comp); 536#endif 537 538// is it a tga? 539extern int stbi_tga_test_memory (stbi_uc const *buffer, int len); 540 541extern stbi_uc *stbi_tga_load (char const *filename, int *x, int *y, int *comp, int req_comp); 542extern stbi_uc *stbi_tga_load_from_memory (stbi_uc const *buffer, int len, int *x, int *y, int *comp, int req_comp); 543#ifndef STBI_NO_STDIO 544extern int stbi_tga_test_file (FILE *f); 545extern stbi_uc *stbi_tga_load_from_file (FILE *f, int *x, int *y, int *comp, int req_comp); 546#endif 547 548// is it a psd? 549extern int stbi_psd_test_memory (stbi_uc const *buffer, int len); 550 551extern stbi_uc *stbi_psd_load (char const *filename, int *x, int *y, int *comp, int req_comp); 552extern stbi_uc *stbi_psd_load_from_memory (stbi_uc const *buffer, int len, int *x, int *y, int *comp, int req_comp); 553#ifndef STBI_NO_STDIO 554extern int stbi_psd_test_file (FILE *f); 555extern stbi_uc *stbi_psd_load_from_file (FILE *f, int *x, int *y, int *comp, int req_comp); 556#endif 557 558// is it an hdr? 559extern int stbi_hdr_test_memory (stbi_uc const *buffer, int len); 560 561extern float * stbi_hdr_load (char const *filename, int *x, int *y, int *comp, int req_comp); 562extern float * stbi_hdr_load_from_memory (stbi_uc const *buffer, int len, int *x, int *y, int *comp, int req_comp); 563#ifndef STBI_NO_STDIO 564extern int stbi_hdr_test_file (FILE *f); 565extern float * stbi_hdr_load_from_file (FILE *f, int *x, int *y, int *comp, int req_comp); 566#endif 567 568// is it a pic? 569extern int stbi_pic_test_memory (stbi_uc const *buffer, int len); 570 571extern stbi_uc *stbi_pic_load (char const *filename, int *x, int *y, int *comp, int req_comp); 572extern stbi_uc *stbi_pic_load_from_memory (stbi_uc const *buffer, int len, int *x, int *y, int *comp, int req_comp); 573#ifndef STBI_NO_STDIO 574extern int stbi_pic_test_file (FILE *f); 575extern stbi_uc *stbi_pic_load_from_file (FILE *f, int *x, int *y, int *comp, int req_comp); 576#endif 577 578// is it a gif? 579extern int stbi_gif_test_memory (stbi_uc const *buffer, int len); 580 581extern stbi_uc *stbi_gif_load (char const *filename, int *x, int *y, int *comp, int req_comp); 582extern stbi_uc *stbi_gif_load_from_memory (stbi_uc const *buffer, int len, int *x, int *y, int *comp, int req_comp); 583extern int stbi_gif_info_from_memory (stbi_uc const *buffer, int len, int *x, int *y, int *comp); 584 585#ifndef STBI_NO_STDIO 586extern int stbi_gif_test_file (FILE *f); 587extern stbi_uc *stbi_gif_load_from_file (FILE *f, int *x, int *y, int *comp, int req_comp); 588extern int stbi_gif_info (char const *filename, int *x, int *y, int *comp); 589extern int stbi_gif_info_from_file (FILE *f, int *x, int *y, int *comp); 590#endif 591 592 593// this is not threadsafe 594static const char *failure_reason; 595 596const char *stbi_failure_reason(void) 597{ 598 return failure_reason; 599} 600 601#ifndef STBI_NO_FAILURE_STRINGS 602static int e(const char *str) 603{ 604 failure_reason = str; 605 return 0; 606} 607#endif 608 609#ifdef STBI_NO_FAILURE_STRINGS 610 #define e(x,y) 0 611#elif defined(STBI_FAILURE_USERMSG) 612 #define e(x,y) e(y) 613#else 614 #define e(x,y) e(x) 615#endif 616 617#define epf(x,y) ((float *) (e(x,y)?NULL:NULL)) 618#define epuc(x,y) ((unsigned char *) (e(x,y)?NULL:NULL)) 619 620void stbi_image_free(void *retval_from_stbi_load) 621{ 622 FREE(retval_from_stbi_load); 623} 624 625#define MAX_LOADERS 32 626stbi_loader *loaders[MAX_LOADERS]; 627static int max_loaders = 0; 628 629int stbi_register_loader(stbi_loader *loader) 630{ 631 int i; 632 for (i=0; i < MAX_LOADERS; ++i) { 633 // already present? 634 if (loaders[i] == loader) 635 return 1; 636 // end of the list? 637 if (loaders[i] == NULL) { 638 loaders[i] = loader; 639 max_loaders = i+1; 640 return 1; 641 } 642 } 643 // no room for it 644 return 0; 645} 646 647#ifndef STBI_NO_HDR 648static float *ldr_to_hdr(stbi_uc *data, int x, int y, int comp); 649static stbi_uc *hdr_to_ldr(float *data, int x, int y, int comp); 650#endif 651 652#ifndef STBI_NO_STDIO 653unsigned char *stbi_load(char const *filename, int *x, int *y, int *comp, int req_comp) 654{ 655 FILE *f = fopen(filename, "rb"); 656 unsigned char *result; 657 if (!f) return epuc("can't fopen", "Unable to open file"); 658 result = stbi_load_from_file(f,x,y,comp,req_comp); 659 fclose(f); 660 return result; 661} 662 663unsigned char *stbi_load_from_file(FILE *f, int *x, int *y, int *comp, int req_comp) 664{ 665 int i; 666 if (stbi_jpeg_test_file(f)) return stbi_jpeg_load_from_file(f,x,y,comp,req_comp); 667 if (stbi_png_test_file(f)) return stbi_png_load_from_file(f,x,y,comp,req_comp); 668 if (stbi_bmp_test_file(f)) return stbi_bmp_load_from_file(f,x,y,comp,req_comp); 669 if (stbi_gif_test_file(f)) return stbi_gif_load_from_file(f,x,y,comp,req_comp); 670 if (stbi_psd_test_file(f)) return stbi_psd_load_from_file(f,x,y,comp,req_comp); 671 if (stbi_pic_test_file(f)) return stbi_pic_load_from_file(f,x,y,comp,req_comp); 672 673 #ifndef STBI_NO_HDR 674 if (stbi_hdr_test_file(f)) { 675 float *hdr = stbi_hdr_load_from_file(f, x,y,comp,req_comp); 676 return hdr_to_ldr(hdr, *x, *y, req_comp ? req_comp : *comp); 677 } 678 #endif 679 680 for (i=0; i < max_loaders; ++i) 681 if (loaders[i]->test_file(f)) 682 return loaders[i]->load_from_file(f,x,y,comp,req_comp); 683 // test tga last because it's a crappy test! 684 if (stbi_tga_test_file(f)) 685 return stbi_tga_load_from_file(f,x,y,comp,req_comp); 686 return epuc("unknown image type", "Image not of any known type, or corrupt"); 687} 688#endif 689 690unsigned char *stbi_load_from_memory(stbi_uc const *buffer, int len, int *x, int *y, int *comp, int req_comp) 691{ 692 int i; 693 if (stbi_jpeg_test_memory(buffer,len)) return stbi_jpeg_load_from_memory(buffer,len,x,y,comp,req_comp); 694 if (stbi_png_test_memory(buffer,len)) return stbi_png_load_from_memory(buffer,len,x,y,comp,req_comp); 695 if (stbi_bmp_test_memory(buffer,len)) return stbi_bmp_load_from_memory(buffer,len,x,y,comp,req_comp); 696 if (stbi_gif_test_memory(buffer,len)) return stbi_gif_load_from_memory(buffer,len,x,y,comp,req_comp); 697 if (stbi_psd_test_memory(buffer,len)) return stbi_psd_load_from_memory(buffer,len,x,y,comp,req_comp); 698 if (stbi_pic_test_memory(buffer,len)) return stbi_pic_load_from_memory(buffer,len,x,y,comp,req_comp); 699 700 #ifndef STBI_NO_HDR 701 if (stbi_hdr_test_memory(buffer, len)) { 702 float *hdr = stbi_hdr_load_from_memory(buffer, len,x,y,comp,req_comp); 703 return hdr_to_ldr(hdr, *x, *y, req_comp ? req_comp : *comp); 704 } 705 #endif 706 707 for (i=0; i < max_loaders; ++i) 708 if (loaders[i]->test_memory(buffer,len)) 709 return loaders[i]->load_from_memory(buffer,len,x,y,comp,req_comp); 710 // test tga last because it's a crappy test! 711 if (stbi_tga_test_memory(buffer,len)) 712 return stbi_tga_load_from_memory(buffer,len,x,y,comp,req_comp); 713 return epuc("unknown image type", "Image not of any known type, or corrupt"); 714} 715 716#ifndef STBI_NO_HDR 717 718#ifndef STBI_NO_STDIO 719float *stbi_loadf(char const *filename, int *x, int *y, int *comp, int req_comp) 720{ 721 FILE *f = fopen(filename, "rb"); 722 float *result; 723 if (!f) return epf("can't fopen", "Unable to open file"); 724 result = stbi_loadf_from_file(f,x,y,comp,req_comp); 725 fclose(f); 726 return result; 727} 728 729float *stbi_loadf_from_file(FILE *f, int *x, int *y, int *comp, int req_comp) 730{ 731 unsigned char *data; 732 #ifndef STBI_NO_HDR 733 if (stbi_hdr_test_file(f)) 734 return stbi_hdr_load_from_file(f,x,y,comp,req_comp); 735 #endif 736 data = stbi_load_from_file(f, x, y, comp, req_comp); 737 if (data) 738 return ldr_to_hdr(data, *x, *y, req_comp ? req_comp : *comp); 739 return epf("unknown image type", "Image not of any known type, or corrupt"); 740} 741#endif 742 743float *stbi_loadf_from_memory(stbi_uc const *buffer, int len, int *x, int *y, int *comp, int req_comp) 744{ 745 stbi_uc *data; 746 #ifndef STBI_NO_HDR 747 if (stbi_hdr_test_memory(buffer, len)) 748 return stbi_hdr_load_from_memory(buffer, len,x,y,comp,req_comp); 749 #endif 750 data = stbi_load_from_memory(buffer, len, x, y, comp, req_comp); 751 if (data) 752 return ldr_to_hdr(data, *x, *y, req_comp ? req_comp : *comp); 753 return epf("unknown image type", "Image not of any known type, or corrupt"); 754} 755#endif 756 757// these is-hdr-or-not is defined independent of whether STBI_NO_HDR is 758// defined, for API simplicity; if STBI_NO_HDR is defined, it always 759// reports false! 760 761int stbi_is_hdr_from_memory(stbi_uc const *buffer, int len) 762{ 763 #ifndef STBI_NO_HDR 764 return stbi_hdr_test_memory(buffer, len); 765 #else 766 STBI_NOTUSED(buffer); 767 STBI_NOTUSED(len); 768 return 0; 769 #endif 770} 771 772#ifndef STBI_NO_STDIO 773extern int stbi_is_hdr (char const *filename) 774{ 775 FILE *f = fopen(filename, "rb"); 776 int result=0; 777 if (f) { 778 result = stbi_is_hdr_from_file(f); 779 fclose(f); 780 } 781 return result; 782} 783 784extern int stbi_is_hdr_from_file(FILE *f) 785{ 786 #ifndef STBI_NO_HDR 787 return stbi_hdr_test_file(f); 788 #else 789 return 0; 790 #endif 791} 792 793#endif 794 795#ifndef STBI_NO_HDR 796static float h2l_gamma_i=1.0f/2.2f, h2l_scale_i=1.0f; 797static float l2h_gamma=2.2f, l2h_scale=1.0f; 798 799void stbi_hdr_to_ldr_gamma(float gamma) { h2l_gamma_i = 1/gamma; } 800void stbi_hdr_to_ldr_scale(float scale) { h2l_scale_i = 1/scale; } 801 802void stbi_ldr_to_hdr_gamma(float gamma) { l2h_gamma = gamma; } 803void stbi_ldr_to_hdr_scale(float scale) { l2h_scale = scale; } 804#endif 805 806 807////////////////////////////////////////////////////////////////////////////// 808// 809// Common code used by all image loaders 810// 811 812enum 813{ 814 SCAN_load=0, 815 SCAN_type, 816 SCAN_header 817}; 818 819typedef struct 820{ 821 uint32 img_x, img_y; 822 int img_n, img_out_n; 823 824 #ifndef STBI_NO_STDIO 825 FILE *img_file; 826 int buflen; 827 uint8 buffer_start[128]; 828 int from_file; 829 #endif 830 uint8 const *img_buffer, *img_buffer_end; 831} stbi; 832 833#ifndef STBI_NO_STDIO 834static void start_file(stbi *s, FILE *f) 835{ 836 s->img_file = f; 837 s->buflen = sizeof(s->buffer_start); 838 s->img_buffer_end = s->buffer_start + s->buflen; 839 s->img_buffer = s->img_buffer_end; 840 s->from_file = 1; 841} 842#endif 843 844static void start_mem(stbi *s, uint8 const *buffer, int len) 845{ 846#ifndef STBI_NO_STDIO 847 s->img_file = NULL; 848 s->from_file = 0; 849#endif 850 s->img_buffer = (uint8 const *) buffer; 851 s->img_buffer_end = (uint8 const *) buffer+len; 852} 853 854#ifndef STBI_NO_STDIO 855static void refill_buffer(stbi *s) 856{ 857 int n = fread(s->buffer_start, 1, s->buflen, s->img_file); 858 if (n == 0) { 859 s->from_file = 0; 860 s->img_buffer = s->img_buffer_end-1; 861#if 0 862 *s->img_buffer = 0; 863#endif 864 } else { 865 s->img_buffer = s->buffer_start; 866 s->img_buffer_end = s->buffer_start + n; 867 } 868} 869#endif 870 871__forceinline static int get8(stbi *s) 872{ 873 if (s->img_buffer < s->img_buffer_end) 874 return *s->img_buffer++; 875#ifndef STBI_NO_STDIO 876 if (s->from_file) { 877 refill_buffer(s); 878 return *s->img_buffer++; 879 } 880#endif 881 return 0; 882} 883 884__forceinline static int at_eof(stbi *s) 885{ 886#ifndef STBI_NO_STDIO 887 if (s->img_file) { 888 if (!feof(s->img_file)) return 0; 889 // if feof() is true, check if buffer = end 890 // special case: we've only got the special 0 character at the end 891 if (s->from_file == 0) return 1; 892 } 893#endif 894 return s->img_buffer >= s->img_buffer_end; 895} 896 897__forceinline static uint8 get8u(stbi *s) 898{ 899 return (uint8) get8(s); 900} 901 902static void skip(stbi *s, int n) 903{ 904#ifndef STBI_NO_STDIO 905 if (s->img_file) { 906 int blen = s->img_buffer_end - s->img_buffer; 907 if (blen < n) { 908 s->img_buffer = s->img_buffer_end; 909 fseek(s->img_file, n - blen, SEEK_CUR); 910 return; 911 } 912 } 913#endif 914 s->img_buffer += n; 915} 916 917static int getn(stbi *s, stbi_uc *buffer, int n) 918{ 919#ifndef STBI_NO_STDIO 920 if (s->img_file) { 921 int blen = s->img_buffer_end - s->img_buffer; 922 if (blen < n) { 923 int res; 924 memcpy(buffer, s->img_buffer, blen); 925 res = ((int) fread(buffer + blen, 1, n - blen, s->img_file) == (n-blen)); 926 s->img_buffer = s->img_buffer_end; 927 return res; 928 } 929 } 930#endif 931 if (s->img_buffer+n <= s->img_buffer_end) { 932 memcpy(buffer, s->img_buffer, n); 933 s->img_buffer += n; 934 return 1; 935 } else 936 return 0; 937} 938 939static int get16(stbi *s) 940{ 941 int z = get8(s); 942 return (z << 8) + get8(s); 943} 944 945static uint32 get32(stbi *s) 946{ 947 uint32 z = get16(s); 948 return (z << 16) + get16(s); 949} 950 951static int get16le(stbi *s) 952{ 953 int z = get8(s); 954 return z + (get8(s) << 8); 955} 956 957static uint32 get32le(stbi *s) 958{ 959 uint32 z = get16le(s); 960 return z + (get16le(s) << 16); 961} 962 963////////////////////////////////////////////////////////////////////////////// 964// 965// generic converter from built-in img_n to req_comp 966// individual types do this automatically as much as possible (e.g. jpeg 967// does all cases internally since it needs to colorspace convert anyway, 968// and it never has alpha, so very few cases ). png can automatically 969// interleave an alpha=255 channel, but falls back to this for other cases 970// 971// assume data buffer is malloced, so malloc a new one and free that one 972// only failure mode is malloc failing 973 974static uint8 compute_y(int r, int g, int b) 975{ 976 return (uint8) (((r*77) + (g*150) + (29*b)) >> 8); 977} 978 979static unsigned char *convert_format(unsigned char *data, int img_n, int req_comp, uint x, uint y) 980{ 981 int i,j; 982 unsigned char *good; 983 984 if (req_comp == img_n) return data; 985 assert(req_comp >= 1 && req_comp <= 4); 986 987 good = (unsigned char *) MALLOC(req_comp * x * y); 988 if (good == NULL) { 989 FREE(data); 990 return epuc("outofmem", "Out of memory"); 991 } 992 993 for (j=0; j < (int) y; ++j) { 994 unsigned char *src = data + j * x * img_n ; 995 unsigned char *dest = good + j * x * req_comp; 996 997 #define COMBO(a,b) ((a)*8+(b)) 998 #define CASE(a,b) case COMBO(a,b): for(i=x-1; i >= 0; --i, src += a, dest += b) 999 // convert source image with img_n components to one with req_comp components; 1000 // avoid switch per pixel, so use switch per scanline and massive macros 1001 switch (COMBO(img_n, req_comp)) { 1002 CASE(1,2) dest[0]=src[0], dest[1]=255; break; 1003 CASE(1,3) dest[0]=dest[1]=dest[2]=src[0]; break; 1004 CASE(1,4) dest[0]=dest[1]=dest[2]=src[0], dest[3]=255; break; 1005 CASE(2,1) dest[0]=src[0]; break; 1006 CASE(2,3) dest[0]=dest[1]=dest[2]=src[0]; break; 1007 CASE(2,4) dest[0]=dest[1]=dest[2]=src[0], dest[3]=src[1]; break; 1008 CASE(3,4) dest[0]=src[0],dest[1]=src[1],dest[2]=src[2],dest[3]=255; break; 1009 CASE(3,1) dest[0]=compute_y(src[0],src[1],src[2]); break; 1010 CASE(3,2) dest[0]=compute_y(src[0],src[1],src[2]), dest[1] = 255; break; 1011 CASE(4,1) dest[0]=compute_y(src[0],src[1],src[2]); break; 1012 CASE(4,2) dest[0]=compute_y(src[0],src[1],src[2]), dest[1] = src[3]; break; 1013 CASE(4,3) dest[0]=src[0],dest[1]=src[1],dest[2]=src[2]; break; 1014 default: assert(0); 1015 } 1016 #undef CASE 1017 } 1018 1019 FREE(data); 1020 return good; 1021} 1022 1023#ifndef STBI_NO_HDR 1024static float *ldr_to_hdr(stbi_uc *data, int x, int y, int comp) 1025{ 1026 int i,k,n; 1027 float *output = (float *) MALLOC(x * y * comp * sizeof(float)); 1028 if (output == NULL) { FREE(data); return epf("outofmem", "Out of memory"); } 1029 // compute number of non-alpha components 1030 if (comp & 1) n = comp; else n = comp-1; 1031 for (i=0; i < x*y; ++i) { 1032 for (k=0; k < n; ++k) { 1033 output[i*comp + k] = (float) pow(data[i*comp+k]/255.0f, l2h_gamma) * l2h_scale; 1034 } 1035 if (k < comp) output[i*comp + k] = data[i*comp+k]/255.0f; 1036 } 1037 FREE(data); 1038 return output; 1039} 1040 1041#define float2int(x) ((int) (x)) 1042static stbi_uc *hdr_to_ldr(float *data, int x, int y, int comp) 1043{ 1044 int i,k,n; 1045 stbi_uc *output = (stbi_uc *) MALLOC(x * y * comp); 1046 if (output == NULL) { FREE(data); return epuc("outofmem", "Out of memory"); } 1047 // compute number of non-alpha components 1048 if (comp & 1) n = comp; else n = comp-1; 1049 for (i=0; i < x*y; ++i) { 1050 for (k=0; k < n; ++k) { 1051 float z = (float) pow(data[i*comp+k]*h2l_scale_i, h2l_gamma_i) * 255 + 0.5f; 1052 if (z < 0) z = 0; 1053 if (z > 255) z = 255; 1054 output[i*comp + k] = (uint8) float2int(z); 1055 } 1056 if (k < comp) { 1057 float z = data[i*comp+k] * 255 + 0.5f; 1058 if (z < 0) z = 0; 1059 if (z > 255) z = 255; 1060 output[i*comp + k] = (uint8) float2int(z); 1061 } 1062 } 1063 FREE(data); 1064 return output; 1065} 1066#endif 1067 1068////////////////////////////////////////////////////////////////////////////// 1069// 1070// "baseline" JPEG/JFIF decoder (not actually fully baseline implementation) 1071// 1072// simple implementation 1073// - channel subsampling of at most 2 in each dimension 1074// - doesn't support delayed output of y-dimension 1075// - simple interface (only one output format: 8-bit interleaved RGB) 1076// - doesn't try to recover corrupt jpegs 1077// - doesn't allow partial loading, loading multiple at once 1078// - still fast on x86 (copying globals into locals doesn't help x86) 1079// - allocates lots of intermediate memory (full size of all components) 1080// - non-interleaved case requires this anyway 1081// - allows good upsampling (see next) 1082// high-quality 1083// - upsampled channels are bilinearly interpolated, even across blocks 1084// - quality integer IDCT derived from IJG's 'slow' 1085// performance 1086// - fast huffman; reasonable integer IDCT 1087// - uses a lot of intermediate memory, could cache poorly 1088// - load http://nothings.org/remote/anemones.jpg 3 times on 2.8Ghz P4 1089// stb_jpeg: 1.34 seconds (MSVC6, default release build) 1090// stb_jpeg: 1.06 seconds (MSVC6, processor = Pentium Pro) 1091// IJL11.dll: 1.08 seconds (compiled by intel) 1092// IJG 1998: 0.98 seconds (MSVC6, makefile provided by IJG) 1093// IJG 1998: 0.95 seconds (MSVC6, makefile + proc=PPro) 1094 1095// huffman decoding acceleration 1096#define FAST_BITS 9 // larger handles more cases; smaller stomps less cache 1097 1098typedef struct 1099{ 1100 uint8 fast[1 << FAST_BITS]; 1101 // weirdly, repacking this into AoS is a 10% speed loss, instead of a win 1102 uint16 code[256]; 1103 uint8 values[256]; 1104 uint8 size[257]; 1105 unsigned int maxcode[18]; 1106 int delta[17]; // old 'firstsymbol' - old 'firstcode' 1107} huffman; 1108 1109typedef struct 1110{ 1111 #ifdef STBI_SIMD 1112 unsigned short dequant2[4][64]; 1113 #endif 1114 stbi s; 1115 huffman huff_dc[4]; 1116 huffman huff_ac[4]; 1117 uint8 dequant[4][64]; 1118 1119// sizes for components, interleaved MCUs 1120 int img_h_max, img_v_max; 1121 int img_mcu_x, img_mcu_y; 1122 int img_mcu_w, img_mcu_h; 1123 1124// definition of jpeg image component 1125 struct 1126 { 1127 int id; 1128 int h,v; 1129 int tq; 1130 int hd,ha; 1131 int dc_pred; 1132 1133 int x,y,w2,h2; 1134 uint8 *data; 1135 void *raw_data; 1136 uint8 *linebuf; 1137 } img_comp[4]; 1138 1139 uint32 code_buffer; // jpeg entropy-coded buffer 1140 int code_bits; // number of valid bits 1141 unsigned char marker; // marker seen while filling entropy buffer 1142 int nomore; // flag if we saw a marker so must stop 1143 1144 int scan_n, order[4]; 1145 int restart_interval, todo; 1146} jpeg; 1147 1148static int build_huffman(huffman *h, int *count) 1149{ 1150 int i,j,k=0,code; 1151 // build size list for each symbol (from JPEG spec) 1152 for (i=0; i < 16; ++i) 1153 for (j=0; j < count[i]; ++j) 1154 h->size[k++] = (uint8) (i+1); 1155 h->size[k] = 0; 1156 1157 // compute actual symbols (from jpeg spec) 1158 code = 0; 1159 k = 0; 1160 for(j=1; j <= 16; ++j) { 1161 // compute delta to add to code to compute symbol id 1162 h->delta[j] = k - code; 1163 if (h->size[k] == j) { 1164 while (h->size[k] == j) 1165 h->code[k++] = (uint16) (code++); 1166 if (code-1 >= (1 << j)) return e("bad code lengths","Corrupt JPEG"); 1167 } 1168 // compute largest code + 1 for this size, preshifted as needed later 1169 h->maxcode[j] = code << (16-j); 1170 code <<= 1; 1171 } 1172 h->maxcode[j] = 0xffffffff; 1173 1174 // build non-spec acceleration table; 255 is flag for not-accelerated 1175 memset(h->fast, 255, 1 << FAST_BITS); 1176 for (i=0; i < k; ++i) { 1177 int s = h->size[i]; 1178 if (s <= FAST_BITS) { 1179 int c = h->code[i] << (FAST_BITS-s); 1180 int m = 1 << (FAST_BITS-s); 1181 for (j=0; j < m; ++j) { 1182 h->fast[c+j] = (uint8) i; 1183 } 1184 } 1185 } 1186 return 1; 1187} 1188 1189static void grow_buffer_unsafe(jpeg *j) 1190{ 1191 do { 1192 int b = j->nomore ? 0 : get8(&j->s); 1193 if (b == 0xff) { 1194 int c = get8(&j->s); 1195 if (c != 0) { 1196 j->marker = (unsigned char) c; 1197 j->nomore = 1; 1198 return; 1199 } 1200 } 1201 j->code_buffer |= b << (24 - j->code_bits); 1202 j->code_bits += 8; 1203 } while (j->code_bits <= 24); 1204} 1205 1206// (1 << n) - 1 1207static uint32 bmask[17]={0,1,3,7,15,31,63,127,255,511,1023,2047,4095,8191,16383,32767,65535}; 1208 1209// decode a jpeg huffman value from the bitstream 1210__forceinline static int decode(jpeg *j, huffman *h) 1211{ 1212 unsigned int temp; 1213 int c,k; 1214 1215 if (j->code_bits < 16) grow_buffer_unsafe(j); 1216 1217 // look at the top FAST_BITS and determine what symbol ID it is, 1218 // if the code is <= FAST_BITS 1219 c = (j->code_buffer >> (32 - FAST_BITS)) & ((1 << FAST_BITS)-1); 1220 k = h->fast[c]; 1221 if (k < 255) { 1222 int s = h->size[k]; 1223 if (s > j->code_bits) 1224 return -1; 1225 j->code_buffer <<= s; 1226 j->code_bits -= s; 1227 return h->values[k]; 1228 } 1229 1230 // naive test is to shift the code_buffer down so k bits are 1231 // valid, then test against maxcode. To speed this up, we've 1232 // preshifted maxcode left so that it has (16-k) 0s at the 1233 // end; in other words, regardless of the number of bits, it 1234 // wants to be compared against something shifted to have 16; 1235 // that way we don't need to shift inside the loop. 1236 temp = j->code_buffer >> 16; 1237 for (k=FAST_BITS+1 ; ; ++k) 1238 if (temp < h->maxcode[k]) 1239 break; 1240 if (k == 17) { 1241 // error! code not found 1242 j->code_bits -= 16; 1243 return -1; 1244 } 1245 1246 if (k > j->code_bits) 1247 return -1; 1248 1249 // convert the huffman code to the symbol id 1250 c = ((j->code_buffer >> (32 - k)) & bmask[k]) + h->delta[k]; 1251 assert((((j->code_buffer) >> (32 - h->size[c])) & bmask[h->size[c]]) == h->code[c]); 1252 1253 // convert the id to a symbol 1254 j->code_bits -= k; 1255 j->code_buffer <<= k; 1256 return h->values[c]; 1257} 1258 1259// combined JPEG 'receive' and JPEG 'extend', since baseline 1260// always extends everything it receives. 1261__forceinline static int extend_receive(jpeg *j, int n) 1262{ 1263 unsigned int m = 1 << (n-1); 1264 unsigned int k; 1265 if (j->code_bits < n) grow_buffer_unsafe(j); 1266 1267 #if 1 1268 k = stbi_lrot(j->code_buffer, n); 1269 j->code_buffer = k & ~bmask[n]; 1270 k &= bmask[n]; 1271 j->code_bits -= n; 1272 #else 1273 k = (j->code_buffer >> (32 - n)) & bmask[n]; 1274 j->code_bits -= n; 1275 j->code_buffer <<= n; 1276 #endif 1277 // the following test is probably a random branch that won't 1278 // predict well. I tried to table accelerate it but failed. 1279 // maybe it's compiling as a conditional move? 1280 if (k < m) 1281 return (-1 << n) + k + 1; 1282 else 1283 return k; 1284} 1285 1286// given a value that's at position X in the zigzag stream, 1287// where does it appear in the 8x8 matrix coded as row-major? 1288static uint8 dezigzag[64+15] = 1289{ 1290 0, 1, 8, 16, 9, 2, 3, 10, 1291 17, 24, 32, 25, 18, 11, 4, 5, 1292 12, 19, 26, 33, 40, 48, 41, 34, 1293 27, 20, 13, 6, 7, 14, 21, 28, 1294 35, 42, 49, 56, 57, 50, 43, 36, 1295 29, 22, 15, 23, 30, 37, 44, 51, 1296 58, 59, 52, 45, 38, 31, 39, 46, 1297 53, 60, 61, 54, 47, 55, 62, 63, 1298 // let corrupt input sample past end 1299 63, 63, 63, 63, 63, 63, 63, 63, 1300 63, 63, 63, 63, 63, 63, 63 1301}; 1302 1303// decode one 64-entry block-- 1304static int decode_block(jpeg *j, short data[64], huffman *hdc, huffman *hac, int b) 1305{ 1306 int diff,dc,k; 1307 int t = decode(j, hdc); 1308 if (t < 0) return e("bad huffman code","Corrupt JPEG"); 1309 1310 // 0 all the ac values now so we can do it 32-bits at a time 1311 memset(data,0,64*sizeof(data[0])); 1312 1313 diff = t ? extend_receive(j, t) : 0; 1314 dc = j->img_comp[b].dc_pred + diff; 1315 j->img_comp[b].dc_pred = dc; 1316 data[0] = (short) dc; 1317 1318 // decode AC components, see JPEG spec 1319 k = 1; 1320 do { 1321 int r,s; 1322 int rs = decode(j, hac); 1323 if (rs < 0) return e("bad huffman code","Corrupt JPEG"); 1324 s = rs & 15; 1325 r = rs >> 4; 1326 if (s == 0) { 1327 if (rs != 0xf0) break; // end block 1328 k += 16; 1329 } else { 1330 k += r; 1331 // decode into unzigzag'd location 1332 data[dezigzag[k++]] = (short) extend_receive(j,s); 1333 } 1334 } while (k < 64); 1335 return 1; 1336} 1337 1338// take a -128..127 value and clamp it and convert to 0..255 1339__forceinline static uint8 clamp(int x) 1340{ 1341 // trick to use a single test to catch both cases 1342 if ((unsigned int) x > 255) { 1343 if (x < 0) return 0; 1344 if (x > 255) return 255; 1345 } 1346 return (uint8) x; 1347} 1348 1349#define f2f(x) (int) (((x) * 4096 + 0.5)) 1350#define fsh(x) ((x) << 12) 1351 1352// derived from jidctint -- DCT_ISLOW 1353#define IDCT_1D(s0,s1,s2,s3,s4,s5,s6,s7) \ 1354 int t0,t1,t2,t3,p1,p2,p3,p4,p5,x0,x1,x2,x3; \ 1355 p2 = s2; \ 1356 p3 = s6; \ 1357 p1 = (p2+p3) * f2f(0.5411961f); \ 1358 t2 = p1 + p3*f2f(-1.847759065f); \ 1359 t3 = p1 + p2*f2f( 0.765366865f); \ 1360 p2 = s0; \ 1361 p3 = s4; \ 1362 t0 = fsh(p2+p3); \ 1363 t1 = fsh(p2-p3); \ 1364 x0 = t0+t3; \ 1365 x3 = t0-t3; \ 1366 x1 = t1+t2; \ 1367 x2 = t1-t2; \ 1368 t0 = s7; \ 1369 t1 = s5; \ 1370 t2 = s3; \ 1371 t3 = s1; \ 1372 p3 = t0+t2; \ 1373 p4 = t1+t3; \ 1374 p1 = t0+t3; \ 1375 p2 = t1+t2; \ 1376 p5 = (p3+p4)*f2f( 1.175875602f); \ 1377 t0 = t0*f2f( 0.298631336f); \ 1378 t1 = t1*f2f( 2.053119869f); \ 1379 t2 = t2*f2f( 3.072711026f); \ 1380 t3 = t3*f2f( 1.501321110f); \ 1381 p1 = p5 + p1*f2f(-0.899976223f); \ 1382 p2 = p5 + p2*f2f(-2.562915447f); \ 1383 p3 = p3*f2f(-1.961570560f); \ 1384 p4 = p4*f2f(-0.390180644f); \ 1385 t3 += p1+p4; \ 1386 t2 += p2+p3; \ 1387 t1 += p2+p4; \ 1388 t0 += p1+p3; 1389 1390#ifdef STBI_SIMD 1391typedef unsigned short stbi_dequantize_t; 1392#else 1393typedef uint8 stbi_dequantize_t; 1394#endif 1395 1396// .344 seconds on 3*anemones.jpg 1397static void idct_block(uint8 *out, int out_stride, short data[64], stbi_dequantize_t *dequantize) 1398{ 1399 int i,val[64],*v=val; 1400 stbi_dequantize_t *dq = dequantize; 1401 uint8 *o; 1402 short *d = data; 1403 1404 // columns 1405 for (i=0; i < 8; ++i,++d,++dq, ++v) { 1406 // if all zeroes, shortcut -- this avoids dequantizing 0s and IDCTing 1407 if (d[ 8]==0 && d[16]==0 && d[24]==0 && d[32]==0 1408 && d[40]==0 && d[48]==0 && d[56]==0) { 1409 // no shortcut 0 seconds 1410 // (1|2|3|4|5|6|7)==0 0 seconds 1411 // all separate -0.047 seconds 1412 // 1 && 2|3 && 4|5 && 6|7: -0.047 seconds 1413 int dcterm = d[0] * dq[0] << 2; 1414 v[0] = v[8] = v[16] = v[24] = v[32] = v[40] = v[48] = v[56] = dcterm; 1415 } else { 1416 IDCT_1D(d[ 0]*dq[ 0],d[ 8]*dq[ 8],d[16]*dq[16],d[24]*dq[24], 1417 d[32]*dq[32],d[40]*dq[40],d[48]*dq[48],d[56]*dq[56]) 1418 // constants scaled things up by 1<<12; let's bring them back 1419 // down, but keep 2 extra bits of precision 1420 x0 += 512; x1 += 512; x2 += 512; x3 += 512; 1421 v[ 0] = (x0+t3) >> 10; 1422 v[56] = (x0-t3) >> 10; 1423 v[ 8] = (x1+t2) >> 10; 1424 v[48] = (x1-t2) >> 10; 1425 v[16] = (x2+t1) >> 10; 1426 v[40] = (x2-t1) >> 10; 1427 v[24] = (x3+t0) >> 10; 1428 v[32] = (x3-t0) >> 10; 1429 } 1430 } 1431 1432 for (i=0, v=val, o=out; i < 8; ++i,v+=8,o+=out_stride) { 1433 // no fast case since the first 1D IDCT spread components out 1434 IDCT_1D(v[0],v[1],v[2],v[3],v[4],v[5],v[6],v[7]) 1435 // constants scaled things up by 1<<12, plus we had 1<<2 from first 1436 // loop, plus horizontal and vertical each scale by sqrt(8) so together 1437 // we've got an extra 1<<3, so 1<<17 total we need to remove. 1438 // so we want to round that, which means adding 0.5 * 1<<17, 1439 // aka 65536. Also, we'll end up with -128 to 127 that we want 1440 // to encode as 0..255 by adding 128, so we'll add that before the shift 1441 x0 += 65536 + (128<<17); 1442 x1 += 65536 + (128<<17); 1443 x2 += 65536 + (128<<17); 1444 x3 += 65536 + (128<<17); 1445 // tried computing the shifts into temps, or'ing the temps to see 1446 // if any were out of range, but that was slower 1447 o[0] = clamp((x0+t3) >> 17); 1448 o[7] = clamp((x0-t3) >> 17); 1449 o[1] = clamp((x1+t2) >> 17); 1450 o[6] = clamp((x1-t2) >> 17); 1451 o[2] = clamp((x2+t1) >> 17); 1452 o[5] = clamp((x2-t1) >> 17); 1453 o[3] = clamp((x3+t0) >> 17); 1454 o[4] = clamp((x3-t0) >> 17); 1455 } 1456} 1457 1458#ifdef STBI_SIMD 1459static stbi_idct_8x8 stbi_idct_installed = idct_block; 1460 1461extern void stbi_install_idct(stbi_idct_8x8 func) 1462{ 1463 stbi_idct_installed = func; 1464} 1465#endif 1466 1467#define MARKER_none 0xff 1468// if there's a pending marker from the entropy stream, return that 1469// otherwise, fetch from the stream and get a marker. if there's no 1470// marker, return 0xff, which is never a valid marker value 1471static uint8 get_marker(jpeg *j) 1472{ 1473 uint8 x; 1474 if (j->marker != MARKER_none) { x = j->marker; j->marker = MARKER_none; return x; } 1475 x = get8u(&j->s); 1476 if (x != 0xff) return MARKER_none; 1477 while (x == 0xff) 1478 x = get8u(&j->s); 1479 return x; 1480} 1481 1482// in each scan, we'll have scan_n components, and the order 1483// of the components is specified by order[] 1484#define RESTART(x) ((x) >= 0xd0 && (x) <= 0xd7) 1485 1486// after a restart interval, reset the entropy decoder and 1487// the dc prediction 1488static void reset(jpeg *j) 1489{ 1490 j->code_bits = 0; 1491 j->code_buffer = 0; 1492 j->nomore = 0; 1493 j->img_comp[0].dc_pred = j->img_comp[1].dc_pred = j->img_comp[2].dc_pred = 0; 1494 j->marker = MARKER_none; 1495 j->todo = j->restart_interval ? j->restart_interval : 0x7fffffff; 1496 // no more than 1<<31 MCUs if no restart_interal? that's plenty safe, 1497 // since we don't even allow 1<<30 pixels 1498} 1499 1500static int parse_entropy_coded_data(jpeg *z) 1501{ 1502 reset(z); 1503 if (z->scan_n == 1) { 1504 int i,j; 1505 #ifdef STBI_SIMD 1506 __declspec(align(16)) 1507 #endif 1508 short data[64]; 1509 int n = z->order[0]; 1510 // non-interleaved data, we just need to process one block at a time, 1511 // in trivial scanline order 1512 // number of blocks to do just depends on how many actual "pixels" this 1513 // component has, independent of interleaved MCU blocking and such 1514 int w = (z->img_comp[n].x+7) >> 3; 1515 int h = (z->img_comp[n].y+7) >> 3; 1516 for (j=0; j < h; ++j) { 1517 for (i=0; i < w; ++i) { 1518 if (!decode_block(z, data, z->huff_dc+z->img_comp[n].hd, z->huff_ac+z->img_comp[n].ha, n)) return 0; 1519 #ifdef STBI_SIMD 1520 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]); 1521 #else 1522 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]); 1523 #endif 1524 // every data block is an MCU, so countdown the restart interval 1525 if (--z->todo <= 0) { 1526 if (z->code_bits < 24) grow_buffer_unsafe(z); 1527 // if it's NOT a restart, then just bail, so we get corrupt data 1528 // rather than no data 1529 if (!RESTART(z->marker)) return 1; 1530 reset(z); 1531 } 1532 } 1533 } 1534 } else { // interleaved! 1535 int i,j,k,x,y; 1536 short data[64]; 1537 for (j=0; j < z->img_mcu_y; ++j) { 1538 for (i=0; i < z->img_mcu_x; ++i) { 1539 // scan an interleaved mcu... process scan_n components in order 1540 for (k=0; k < z->scan_n; ++k) { 1541 int n = z->order[k]; 1542 // scan out an mcu's worth of this component; that's just determined 1543 // by the basic H and V specified for the component 1544 for (y=0; y < z->img_comp[n].v; ++y) { 1545 for (x=0; x < z->img_comp[n].h; ++x) { 1546 int x2 = (i*z->img_comp[n].h + x)*8; 1547 int y2 = (j*z->img_comp[n].v + y)*8; 1548 if (!decode_block(z, data, z->huff_dc+z->img_comp[n].hd, z->huff_ac+z->img_comp[n].ha, n)) return 0; 1549 #ifdef STBI_SIMD 1550 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]); 1551 #else 1552 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]); 1553 #endif 1554 } 1555 } 1556 } 1557 // after all interleaved components, that's an interleaved MCU, 1558 // so now count down the restart interval 1559 if (--z->todo <= 0) { 1560 if (z->code_bits < 24) grow_buffer_unsafe(z); 1561 // if it's NOT a restart, then just bail, so we get corrupt data 1562 // rather than no data 1563 if (!RESTART(z->marker)) return 1; 1564 reset(z); 1565 } 1566 } 1567 } 1568 } 1569 return 1; 1570} 1571 1572static int process_marker(jpeg *z, int marker) 1573{ 1574 int L; 1575 switch (marker) { 1576 case MARKER_none: // no marker found 1577 return e("expected marker","Corrupt JPEG"); 1578 1579 case 0xC2: // SOF - progressive 1580 return e("progressive jpeg","JPEG format not supported (progressive)"); 1581 1582 case 0xDD: // DRI - specify restart interval 1583 if (get16(&z->s) != 4) return e("bad DRI len","Corrupt JPEG"); 1584 z->restart_interval = get16(&z->s); 1585 return 1; 1586 1587 case 0xDB: // DQT - define quantization table 1588 L = get16(&z->s)-2; 1589 while (L > 0) { 1590 int q = get8(&z->s); 1591 int p = q >> 4; 1592 int t = q & 15,i; 1593 if (p != 0) return e("bad DQT type","Corrupt JPEG"); 1594 if (t > 3) return e("bad DQT table","Corrupt JPEG"); 1595 for (i=0; i < 64; ++i) 1596 z->dequant[t][dezigzag[i]] = get8u(&z->s); 1597 #ifdef STBI_SIMD 1598 for (i=0; i < 64; ++i) 1599 z->dequant2[t][i] = z->dequant[t][i]; 1600 #endif 1601 L -= 65; 1602 } 1603 return L==0; 1604 1605 case 0xC4: // DHT - define huffman table 1606 L = get16(&z->s)-2; 1607 while (L > 0) { 1608 uint8 *v; 1609 int sizes[16],i,m=0; 1610 int q = get8(&z->s); 1611 int tc = q >> 4; 1612 int th = q & 15; 1613 if (tc > 1 || th > 3) return e("bad DHT header","Corrupt JPEG"); 1614 for (i=0; i < 16; ++i) { 1615 sizes[i] = get8(&z->s); 1616 m += sizes[i]; 1617 } 1618 L -= 17; 1619 if (tc == 0) { 1620 if (!build_huffman(z->huff_dc+th, sizes)) return 0; 1621 v = z->huff_dc[th].values; 1622 } else { 1623 if (!build_huffman(z->huff_ac+th, sizes)) return 0; 1624 v = z->huff_ac[th].values; 1625 } 1626 for (i=0; i < m; ++i) 1627 v[i] = get8u(&z->s); 1628 L -= m; 1629 } 1630 return L==0; 1631 } 1632 // check for comment block or APP blocks 1633 if ((marker >= 0xE0 && marker <= 0xEF) || marker == 0xFE) { 1634 skip(&z->s, get16(&z->s)-2); 1635 return 1; 1636 } 1637 return 0; 1638} 1639 1640// after we see SOS 1641static int process_scan_header(jpeg *z) 1642{ 1643 int i; 1644 int Ls = get16(&z->s); 1645 z->scan_n = get8(&z->s); 1646 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"); 1647 if (Ls != 6+2*z->scan_n) return e("bad SOS len","Corrupt JPEG"); 1648 for (i=0; i < z->scan_n; ++i) { 1649 int id = get8(&z->s), which; 1650 int q = get8(&z->s); 1651 for (which = 0; which < z->s.img_n; ++which) 1652 if (z->img_comp[which].id == id) 1653 break; 1654 if (which == z->s.img_n) return 0; 1655 z->img_comp[which].hd = q >> 4; if (z->img_comp[which].hd > 3) return e("bad DC huff","Corrupt JPEG"); 1656 z->img_comp[which].ha = q & 15; if (z->img_comp[which].ha > 3) return e("bad AC huff","Corrupt JPEG"); 1657 z->order[i] = which; 1658 } 1659 if (get8(&z->s) != 0) return e("bad SOS","Corrupt JPEG"); 1660 get8(&z->s); // should be 63, but might be 0 1661 if (get8(&z->s) != 0) return e("bad SOS","Corrupt JPEG"); 1662 1663 return 1; 1664} 1665 1666static int process_frame_header(jpeg *z, int scan) 1667{ 1668 stbi *s = &z->s; 1669 int Lf,p,i,q, h_max=1,v_max=1,c; 1670 Lf = get16(s); if (Lf < 11) return e("bad SOF len","Corrupt JPEG"); // JPEG 1671 p = get8(s); if (p != 8) return e("only 8-bit","JPEG format not supported: 8-bit only"); // JPEG baseline 1672 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 1673 s->img_x = get16(s); if (s->img_x == 0) return e("0 width","Corrupt JPEG"); // JPEG requires 1674 c = get8(s); 1675 if (c != 3 && c != 1) return e("bad component count","Corrupt JPEG"); // JFIF requires 1676 s->img_n = c; 1677 for (i=0; i < c; ++i) { 1678 z->img_comp[i].data = NULL; 1679 z->img_comp[i].linebuf = NULL; 1680 } 1681 1682 if (Lf != 8+3*s->img_n) return e("bad SOF len","Corrupt JPEG"); 1683 1684 for (i=0; i < s->img_n; ++i) { 1685 z->img_comp[i].id = get8(s); 1686 if (z->img_comp[i].id != i+1) // JFIF requires 1687 if (z->img_comp[i].id != i) // some version of jpegtran outputs non-JFIF-compliant files! 1688 return e("bad component ID","Corrupt JPEG"); 1689 q = get8(s); 1690 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"); 1691 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"); 1692 z->img_comp[i].tq = get8(s); if (z->img_comp[i].tq > 3) return e("bad TQ","Corrupt JPEG"); 1693 } 1694 1695 if (scan != SCAN_load) return 1; 1696 1697 if ((1 << 30) / s->img_x / s->img_n < s->img_y) return e("too large", "Image too large to decode"); 1698 1699 for (i=0; i < s->img_n; ++i) { 1700 if (z->img_comp[i].h > h_max) h_max = z->img_comp[i].h; 1701 if (z->img_comp[i].v > v_max) v_max = z->img_comp[i].v; 1702 } 1703 1704 // compute interleaved mcu info 1705 z->img_h_max = h_max; 1706 z->img_v_max = v_max; 1707 z->img_mcu_w = h_max * 8; 1708 z->img_mcu_h = v_max * 8; 1709 z->img_mcu_x = (s->img_x + z->img_mcu_w-1) / z->img_mcu_w; 1710 z->img_mcu_y = (s->img_y + z->img_mcu_h-1) / z->img_mcu_h; 1711 1712 for (i=0; i < s->img_n; ++i) { 1713 // number of effective pixels (e.g. for non-interleaved MCU) 1714 z->img_comp[i].x = (s->img_x * z->img_comp[i].h + h_max-1) / h_max; 1715 z->img_comp[i].y = (s->img_y * z->img_comp[i].v + v_max-1) / v_max; 1716 // to simplify generation, we'll allocate enough memory to decode 1717 // the bogus oversized data from using interleaved MCUs and their 1718 // big blocks (e.g. a 16x16 iMCU on an image of width 33); we won't 1719 // discard the extra data until colorspace conversion 1720 z->img_comp[i].w2 = z->img_mcu_x * z->img_comp[i].h * 8; 1721 z->img_comp[i].h2 = z->img_mcu_y * z->img_comp[i].v * 8; 1722 z->img_comp[i].raw_data = MALLOC(z->img_comp[i].w2 * z->img_comp[i].h2+15); 1723 if (z->img_comp[i].raw_data == NULL) { 1724 for(--i; i >= 0; --i) { 1725 FREE(z->img_comp[i].raw_data); 1726 z->img_comp[i].data = NULL; 1727 } 1728 return e("outofmem", "Out of memory"); 1729 } 1730 // align blocks for installable-idct using mmx/sse 1731 z->img_comp[i].data = (uint8*) (((size_t) z->img_comp[i].raw_data + 15) & ~15); 1732 z->img_comp[i].linebuf = NULL; 1733 } 1734 1735 return 1; 1736} 1737 1738// use comparisons since in some cases we handle more than one case (e.g. SOF) 1739#define DNL(x) ((x) == 0xdc) 1740#define SOI(x) ((x) == 0xd8) 1741#define EOI(x) ((x) == 0xd9) 1742#define SOF(x) ((x) == 0xc0 || (x) == 0xc1) 1743#define SOS(x) ((x) == 0xda) 1744 1745static int decode_jpeg_header(jpeg *z, int scan) 1746{ 1747 int m; 1748 z->marker = MARKER_none; // initialize cached marker to empty 1749 m = get_marker(z); 1750 if (!SOI(m)) return e("no SOI","Corrupt JPEG"); 1751 if (scan == SCAN_type) return 1; 1752 m = get_marker(z); 1753 while (!SOF(m)) { 1754 if (!process_marker(z,m)) return 0; 1755 m = get_marker(z); 1756 while (m == MARKER_none) { 1757 // some files have extra padding after their blocks, so ok, we'll scan 1758 if (at_eof(&z->s)) return e("no SOF", "Corrupt JPEG"); 1759 m = get_marker(z); 1760 } 1761 } 1762 if (!process_frame_header(z, scan)) return 0; 1763 return 1; 1764} 1765 1766static int decode_jpeg_image(jpeg *j) 1767{ 1768 int m; 1769 j->restart_interval = 0; 1770 if (!decode_jpeg_header(j, SCAN_load)) return 0; 1771 m = get_marker(j); 1772 while (!EOI(m)) { 1773 if (SOS(m)) { 1774 if (!process_scan_header(j)) return 0; 1775 if (!parse_entropy_coded_data(j)) return 0; 1776 if (j->marker == MARKER_none ) { 1777 // handle 0s at the end of image data from IP Kamera 9060 1778 while (!at_eof(&j->s)) { 1779 int x = get8(&j->s); 1780 if (x == 255) { 1781 j->marker = get8u(&j->s); 1782 break; 1783 } else if (x != 0) { 1784 return 0; 1785 } 1786 } 1787 // if we reach eof without hitting a marker, get_marker() below will fail and we'll eventually return 0 1788 } 1789 } else { 1790 if (!process_marker(j, m)) return 0; 1791 } 1792 m = get_marker(j); 1793 } 1794 return 1; 1795} 1796 1797// static jfif-centered resampling (across block boundaries) 1798 1799typedef uint8 *(*resample_row_func)(uint8 *out, uint8 *in0, uint8 *in1, 1800 int w, int hs); 1801 1802#define div4(x) ((uint8) ((x) >> 2)) 1803 1804static uint8 *resample_row_1(uint8 *out, uint8 *in_near, uint8 *in_far, int w, int hs) 1805{ 1806 STBI_NOTUSED(out); 1807 STBI_NOTUSED(in_far); 1808 STBI_NOTUSED(w); 1809 STBI_NOTUSED(hs); 1810 return in_near; 1811} 1812 1813static uint8* resample_row_v_2(uint8 *out, uint8 *in_near, uint8 *in_far, int w, int hs) 1814{ 1815 // need to generate two samples vertically for every one in input 1816 int i; 1817 STBI_NOTUSED(hs); 1818 for (i=0; i < w; ++i) 1819 out[i] = div4(3*in_near[i] + in_far[i] + 2); 1820 return out; 1821} 1822 1823static uint8* resample_row_h_2(uint8 *out, uint8 *in_near, uint8 *in_far, int w, int hs) 1824{ 1825 // need to generate two samples horizontally for every one in input 1826 int i; 1827 uint8 *input = in_near; 1828 1829 if (w == 1) { 1830 // if only one sample, can't do any interpolation 1831 out[0] = out[1] = input[0]; 1832 return out; 1833 } 1834 1835 out[0] = input[0]; 1836 out[1] = div4(input[0]*3 + input[1] + 2); 1837 for (i=1; i < w-1; ++i) { 1838 int n = 3*input[i]+2; 1839 out[i*2+0] = div4(n+input[i-1]); 1840 out[i*2+1] = div4(n+input[i+1]); 1841 } 1842 out[i*2+0] = div4(input[w-2]*3 + input[w-1] + 2); 1843 out[i*2+1] = input[w-1]; 1844 1845 STBI_NOTUSED(in_far); 1846 STBI_NOTUSED(hs); 1847 1848 return out; 1849} 1850 1851#define div16(x) ((uint8) ((x) >> 4)) 1852 1853static uint8 *resample_row_hv_2(uint8 *out, uint8 *in_near, uint8 *in_far, int w, int hs) 1854{ 1855 // need to generate 2x2 samples for every one in input 1856 int i,t0,t1; 1857 if (w == 1) { 1858 out[0] = out[1] = div4(3*in_near[0] + in_far[0] + 2); 1859 return out; 1860 } 1861 1862 t1 = 3*in_near[0] + in_far[0]; 1863 out[0] = div4(t1+2); 1864 for (i=1; i < w; ++i) { 1865 t0 = t1; 1866 t1 = 3*in_near[i]+in_far[i]; 1867 out[i*2-1] = div16(3*t0 + t1 + 8); 1868 out[i*2 ] = div16(3*t1 + t0 + 8); 1869 } 1870 out[w*2-1] = div4(t1+2); 1871 1872 STBI_NOTUSED(hs); 1873 1874 return out; 1875} 1876 1877static uint8 *resample_row_generic(uint8 *out, uint8 *in_near, uint8 *in_far, int w, int hs) 1878{ 1879 // resample with nearest-neighbor 1880 int i,j; 1881 in_far = in_far; 1882 for (i=0; i < w; ++i) 1883 for (j=0; j < hs; ++j) 1884 out[i*hs+j] = in_near[i]; 1885 return out; 1886} 1887 1888#define float2fixed(x) ((int) ((x) * 65536 + 0.5)) 1889 1890// 0.38 seconds on 3*anemones.jpg (0.25 with processor = Pro) 1891// VC6 without processor=Pro is generating multiple LEAs per multiply! 1892static void YCbCr_to_RGB_row(uint8 *out, const uint8 *y, const uint8 *pcb, const uint8 *pcr, int count, int step) 1893{ 1894 int i; 1895 for (i=0; i < count; ++i) { 1896 int y_fixed = (y[i] << 16) + 32768; // rounding 1897 int r,g,b; 1898 int cr = pcr[i] - 128; 1899 int cb = pcb[i] - 128; 1900 r = y_fixed + cr*float2fixed(1.40200f); 1901 g = y_fixed - cr*float2fixed(0.71414f) - cb*float2fixed(0.34414f); 1902 b = y_fixed + cb*float2fixed(1.77200f); 1903 r >>= 16; 1904 g >>= 16; 1905 b >>= 16; 1906 if ((unsigned) r > 255) { if (r < 0) r = 0; else r = 255; } 1907 if ((unsigned) g > 255) { if (g < 0) g = 0; else g = 255; } 1908 if ((unsigned) b > 255) { if (b < 0) b = 0; else b = 255; } 1909 out[0] = (uint8)r; 1910 out[1] = (uint8)g; 1911 out[2] = (uint8)b; 1912 out[3] = 255; 1913 out += step; 1914 } 1915} 1916 1917#ifdef STBI_SIMD 1918static stbi_YCbCr_to_RGB_run stbi_YCbCr_installed = YCbCr_to_RGB_row; 1919 1920void stbi_install_YCbCr_to_RGB(stbi_YCbCr_to_RGB_run func) 1921{ 1922 stbi_YCbCr_installed = func; 1923} 1924#endif 1925 1926 1927// clean up the temporary component buffers 1928static void cleanup_jpeg(jpeg *j) 1929{ 1930 int i; 1931 for (i=0; i < j->s.img_n; ++i) { 1932 if (j->img_comp[i].data) { 1933 FREE(j->img_comp[i].raw_data); 1934 j->img_comp[i].data = NULL; 1935 } 1936 if (j->img_comp[i].linebuf) { 1937 FREE(j->img_comp[i].linebuf); 1938 j->img_comp[i].linebuf = NULL; 1939 } 1940 } 1941} 1942 1943typedef struct 1944{ 1945 resample_row_func resample; 1946 uint8 *line0,*line1; 1947 int hs,vs; // expansion factor in each axis 1948 int w_lores; // horizontal pixels pre-expansion 1949 int ystep; // how far through vertical expansion we are 1950 int ypos; // which pre-expansion row we're on 1951} stbi_resample; 1952 1953static uint8 *load_jpeg_image(jpeg *z, int *out_x, int *out_y, int *comp, int req_comp) 1954{ 1955 int n, decode_n; 1956 // validate req_comp 1957 if (req_comp < 0 || req_comp > 4) return epuc("bad req_comp", "Internal error"); 1958 z->s.img_n = 0; 1959 1960 // load a jpeg image from whichever source 1961 if (!decode_jpeg_image(z)) { cleanup_jpeg(z); return NULL; } 1962 1963 // determine actual number of components to generate 1964 n = req_comp ? req_comp : z->s.img_n; 1965 1966 if (z->s.img_n == 3 && n < 3) 1967 decode_n = 1; 1968 else 1969 decode_n = z->s.img_n; 1970 1971 // resample and color-convert 1972 { 1973 int k; 1974 uint i,j; 1975 uint8 *output; 1976 uint8 *coutput[4]; 1977 1978 stbi_resample res_comp[4]; 1979 1980 for (k=0; k < decode_n; ++k) { 1981 stbi_resample *r = &res_comp[k]; 1982 1983 // allocate line buffer big enough for upsampling off the edges 1984 // with upsample factor of 4 1985 z->img_comp[k].linebuf = (uint8 *) MALLOC(z->s.img_x + 3); 1986 if (!z->img_comp[k].linebuf) { cleanup_jpeg(z); return epuc("outofmem", "Out of memory"); } 1987 1988 r->hs = z->img_h_max / z->img_comp[k].h; 1989 r->vs = z->img_v_max / z->img_comp[k].v; 1990 r->ystep = r->vs >> 1; 1991 r->w_lores = (z->s.img_x + r->hs-1) / r->hs; 1992 r->ypos = 0; 1993 r->line0 = r->line1 = z->img_comp[k].data; 1994 1995 if (r->hs == 1 && r->vs == 1) r->resample = resample_row_1; 1996 else if (r->hs == 1 && r->vs == 2) r->resample = resample_row_v_2; 1997 else if (r->hs == 2 && r->vs == 1) r->resample = resample_row_h_2; 1998 else if (r->hs == 2 && r->vs == 2) r->resample = resample_row_hv_2; 1999 else r->resample = resample_row_generic; 2000 } 2001 2002 // can't error after this so, this is safe 2003 output = (uint8 *) MALLOC(n * z->s.img_x * z->s.img_y + 1); 2004 if (!output) { cleanup_jpeg(z); return epuc("outofmem", "Out of memory"); } 2005 2006 // now go ahead and resample 2007 for (j=0; j < z->s.img_y; ++j) { 2008 uint8 *out = output + n * z->s.img_x * j; 2009 for (k=0; k < decode_n; ++k) { 2010 stbi_resample *r = &res_comp[k]; 2011 int y_bot = r->ystep >= (r->vs >> 1); 2012 coutput[k] = r->resample(z->img_comp[k].linebuf, 2013 y_bot ? r->line1 : r->line0, 2014 y_bot ? r->line0 : r->line1, 2015 r->w_lores, r->hs); 2016 if (++r->ystep >= r->vs) { 2017 r->ystep = 0; 2018 r->line0 = r->line1; 2019 if (++r->ypos < z->img_comp[k].y) 2020 r->line1 += z->img_comp[k].w2; 2021 } 2022 } 2023 if (n >= 3) { 2024 uint8 *y = coutput[0]; 2025 if (z->s.img_n == 3) { 2026 #ifdef STBI_SIMD 2027 stbi_YCbCr_installed(out, y, coutput[1], coutput[2], z->s.img_x, n); 2028 #else 2029 YCbCr_to_RGB_row(out, y, coutput[1], coutput[2], z->s.img_x, n); 2030 #endif 2031 } else 2032 for (i=0; i < z->s.img_x; ++i) { 2033 out[0] = out[1] = out[2] = y[i]; 2034 out[3] = 255; // not used if n==3 2035 out += n; 2036 } 2037 } else { 2038 uint8 *y = coutput[0]; 2039 if (n == 1) 2040 for (i=0; i < z->s.img_x; ++i) out[i] = y[i]; 2041 else 2042 for (i=0; i < z->s.img_x; ++i) *out++ = y[i], *out++ = 255; 2043 } 2044 } 2045 cleanup_jpeg(z); 2046 *out_x = z->s.img_x; 2047 *out_y = z->s.img_y; 2048 if (comp) *comp = z->s.img_n; // report original components, not output 2049 return output; 2050 } 2051} 2052 2053#ifndef STBI_NO_STDIO 2054unsigned char *stbi_jpeg_load_from_file(FILE *f, int *x, int *y, int *comp, int req_comp) 2055{ 2056 jpeg j; 2057 start_file(&j.s, f); 2058 return load_jpeg_image(&j, x,y,comp,req_comp); 2059} 2060 2061unsigned char *stbi_jpeg_load(char const *filename, int *x, int *y, int *comp, int req_comp) 2062{ 2063 unsigned char *data; 2064 FILE *f = fopen(filename, "rb"); 2065 if (!f) return NULL; 2066 data = stbi_jpeg_load_from_file(f,x,y,comp,req_comp); 2067 fclose(f); 2068 return data; 2069} 2070#endif 2071 2072unsigned char *stbi_jpeg_load_from_memory(stbi_uc const *buffer, int len, int *x, int *y, int *comp, int req_comp) 2073{ 2074 #ifdef STBI_SMALL_STACK 2075 unsigned char *result; 2076 jpeg *j = (jpeg *) MALLOC(sizeof(*j)); 2077 start_mem(&j->s, buffer, len); 2078 result = load_jpeg_image(j,x,y,comp,req_comp); 2079 FREE(j); 2080 return result; 2081 #else 2082 jpeg j; 2083 start_mem(&j.s, buffer,len); 2084 return load_jpeg_image(&j, x,y,comp,req_comp); 2085 #endif 2086} 2087 2088static int stbi_jpeg_info_raw(jpeg *j, int *x, int *y, int *comp) 2089{ 2090 if (!decode_jpeg_header(j, SCAN_header)) 2091 return 0; 2092 if (x) *x = j->s.img_x; 2093 if (y) *y = j->s.img_y; 2094 if (comp) *comp = j->s.img_n; 2095 return 1; 2096} 2097 2098#ifndef STBI_NO_STDIO 2099int stbi_jpeg_test_file(FILE *f) 2100{ 2101 int n,r; 2102 jpeg j; 2103 n = ftell(f); 2104 start_file(&j.s, f); 2105 r = decode_jpeg_header(&j, SCAN_type); 2106 fseek(f,n,SEEK_SET); 2107 return r; 2108} 2109 2110int stbi_jpeg_info_from_file(FILE *f, int *x, int *y, int *comp) 2111{ 2112 jpeg j; 2113 long n = ftell(f); 2114 int res; 2115 start_file(&j.s, f); 2116 res = stbi_jpeg_info_raw(&j, x, y, comp); 2117 fseek(f, n, SEEK_SET); 2118 return res; 2119} 2120 2121int stbi_jpeg_info(char const *filename, int *x, int *y, int *comp) 2122{ 2123 FILE *f = fopen(filename, "rb"); 2124 int result; 2125 if (!f) return e("can't fopen", "Unable to open file"); 2126 result = stbi_jpeg_info_from_file(f, x, y, comp); 2127 fclose(f); 2128 return result; 2129} 2130#endif 2131 2132int stbi_jpeg_test_memory(stbi_uc const *buffer, int len) 2133{ 2134 jpeg j; 2135 start_mem(&j.s, buffer,len); 2136 return decode_jpeg_header(&j, SCAN_type); 2137} 2138 2139int stbi_jpeg_info_from_memory(stbi_uc const *buffer, int len, int *x, int *y, int *comp) 2140{ 2141 jpeg j; 2142 start_mem(&j.s, buffer, len); 2143 return stbi_jpeg_info_raw(&j, x, y, comp); 2144} 2145 2146#ifndef STBI_NO_STDIO 2147extern int stbi_jpeg_info (char const *filename, int *x, int *y, int *comp); 2148extern int stbi_jpeg_info_from_file (FILE *f, int *x, int *y, int *comp); 2149#endif 2150extern int stbi_jpeg_info_from_memory(stbi_uc const *buffer, int len, int *x, int *y, int *comp); 2151 2152// public domain zlib decode v0.2 Sean Barrett 2006-11-18 2153// simple implementation 2154// - all input must be provided in an upfront buffer 2155// - all output is written to a single output buffer (can malloc/realloc) 2156// performance 2157// - fast huffman 2158 2159// fast-way is faster to check than jpeg huffman, but slow way is slower 2160#define ZFAST_BITS 9 // accelerate all cases in default tables 2161#define ZFAST_MASK ((1 << ZFAST_BITS) - 1) 2162 2163// zlib-style huffman encoding 2164// (jpegs packs from left, zlib from right, so can't share code) 2165typedef struct 2166{ 2167 uint16 fast[1 << ZFAST_BITS]; 2168 uint16 firstcode[16]; 2169 int maxcode[17]; 2170 uint16 firstsymbol[16]; 2171 uint8 size[288]; 2172 uint16 value[288]; 2173} zhuffman; 2174 2175__forceinline static int bitreverse16(int n) 2176{ 2177 n = ((n & 0xAAAA) >> 1) | ((n & 0x5555) << 1); 2178 n = ((n & 0xCCCC) >> 2) | ((n & 0x3333) << 2); 2179 n = ((n & 0xF0F0) >> 4) | ((n & 0x0F0F) << 4); 2180 n = ((n & 0xFF00) >> 8) | ((n & 0x00FF) << 8); 2181 return n; 2182} 2183 2184__forceinline static int bit_reverse(int v, int bits) 2185{ 2186 assert(bits <= 16); 2187 // to bit reverse n bits, reverse 16 and shift 2188 // e.g. 11 bits, bit reverse and shift away 5 2189 return bitreverse16(v) >> (16-bits); 2190} 2191 2192static int zbuild_huffman(zhuffman *z, uint8 *sizelist, int num) 2193{ 2194 int i,k=0; 2195 int code, next_code[16], sizes[17]; 2196 2197 // DEFLATE spec for generating codes 2198 memset(sizes, 0, sizeof(sizes)); 2199 memset(z->fast, 255, sizeof(z->fast)); 2200 for (i=0; i < num; ++i) 2201 ++sizes[sizelist[i]]; 2202 sizes[0] = 0; 2203 for (i=1; i < 16; ++i) 2204 assert(sizes[i] <= (1 << i)); 2205 code = 0; 2206 for (i=1; i < 16; ++i) { 2207 next_code[i] = code; 2208 z->firstcode[i] = (uint16) code; 2209 z->firstsymbol[i] = (uint16) k; 2210 code = (code + sizes[i]); 2211 if (sizes[i]) 2212 if (code-1 >= (1 << i)) return e("bad codelengths","Corrupt JPEG"); 2213 z->maxcode[i] = code << (16-i); // preshift for inner loop 2214 code <<= 1; 2215 k += sizes[i]; 2216 } 2217 z->maxcode[16] = 0x10000; // sentinel 2218 for (i=0; i < num; ++i) { 2219 int s = sizelist[i]; 2220 if (s) { 2221 int c = next_code[s] - z->firstcode[s] + z->firstsymbol[s]; 2222 z->size[c] = (uint8)s; 2223 z->value[c] = (uint16)i; 2224 if (s <= ZFAST_BITS) { 2225 int m = bit_reverse(next_code[s],s); 2226 while (m < (1 << ZFAST_BITS)) { 2227 z->fast[m] = (uint16) c; 2228 m += (1 << s); 2229 } 2230 } 2231 ++next_code[s]; 2232 } 2233 } 2234 return 1; 2235} 2236 2237// zlib-from-memory implementation for PNG reading 2238// because PNG allows splitting the zlib stream arbitrarily, 2239// and it's annoying structurally to have PNG call ZLIB call PNG, 2240// we require PNG read all the IDATs and combine them into a single 2241// memory buffer 2242 2243typedef struct 2244{ 2245 uint8 const *zbuffer, *zbuffer_end; 2246 int num_bits; 2247 uint32 code_buffer; 2248 2249 char *zout; 2250 char *zout_start; 2251 char *zout_end; 2252 int z_expandable; 2253 2254 zhuffman z_length, z_distance; 2255} zbuf; 2256 2257__forceinline static int zget8(zbuf *z) 2258{ 2259 if (z->zbuffer >= z->zbuffer_end) return 0; 2260 return *z->zbuffer++; 2261} 2262 2263static void fill_bits(zbuf *z) 2264{ 2265 do { 2266 assert(z->code_buffer < (1U << z->num_bits)); 2267 z->code_buffer |= zget8(z) << z->num_bits; 2268 z->num_bits += 8; 2269 } while (z->num_bits <= 24); 2270} 2271 2272__forceinline static unsigned int zreceive(zbuf *z, int n) 2273{ 2274 unsigned int k; 2275 if (z->num_bits < n) fill_bits(z); 2276 k = z->code_buffer & ((1 << n) - 1); 2277 z->code_buffer >>= n; 2278 z->num_bits -= n; 2279 return k; 2280} 2281 2282__forceinline static int zhuffman_decode(zbuf *a, zhuffman *z) 2283{ 2284 int b,s,k; 2285 if (a->num_bits < 16) fill_bits(a); 2286 b = z->fast[a->code_buffer & ZFAST_MASK]; 2287 if (b < 0xffff) { 2288 s = z->size[b]; 2289 a->code_buffer >>= s; 2290 a->num_bits -= s; 2291 return z->value[b]; 2292 } 2293 2294 // not resolved by fast table, so compute it the slow way 2295 // use jpeg approach, which requires MSbits at top 2296 k = bit_reverse(a->code_buffer, 16); 2297 for (s=ZFAST_BITS+1; ; ++s) 2298 if (k < z->maxcode[s]) 2299 break; 2300 if (s == 16) return -1; // invalid code! 2301 // code size is s, so: 2302 b = (k >> (16-s)) - z->firstcode[s] + z->firstsymbol[s]; 2303 assert(z->size[b] == s); 2304 a->code_buffer >>= s; 2305 a->num_bits -= s; 2306 return z->value[b]; 2307} 2308 2309static int expand(zbuf *z, int n) // need to make room for n bytes 2310{ 2311 char *q; 2312 int cur, limit; 2313 if (!z->z_expandable) return e("output buffer limit","Corrupt PNG"); 2314 cur = (int) (z->zout - z->zout_start); 2315 limit = (int) (z->zout_end - z->zout_start); 2316 while (cur + n > limit) 2317 limit *= 2; 2318 q = (char *) REALLOC(z->zout_start, limit); 2319 if (q == NULL) return e("outofmem", "Out of memory"); 2320 z->zout_start = q; 2321 z->zout = q + cur; 2322 z->zout_end = q + limit; 2323 return 1; 2324} 2325 2326static int length_base[31] = { 2327 3,4,5,6,7,8,9,10,11,13, 2328 15,17,19,23,27,31,35,43,51,59, 2329 67,83,99,115,131,163,195,227,258,0,0 }; 2330 2331static int length_extra[31]= 2332{ 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 }; 2333 2334static int dist_base[32] = { 1,2,3,4,5,7,9,13,17,25,33,49,65,97,129,193, 2335257,385,513,769,1025,1537,2049,3073,4097,6145,8193,12289,16385,24577,0,0}; 2336 2337static int dist_extra[32] = 2338{ 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}; 2339 2340static int parse_huffman_block(zbuf *a) 2341{ 2342 for(;;) { 2343 int z = zhuffman_decode(a, &a->z_length); 2344 if (z < 256) { 2345 if (z < 0) return e("bad huffman code","Corrupt PNG"); // error in huffman codes 2346 if (a->zout >= a->zout_end) if (!expand(a, 1)) return 0; 2347 *a->zout++ = (char) z; 2348 } else { 2349 uint8 *p; 2350 int len,dist; 2351 if (z == 256) return 1; 2352 z -= 257; 2353 len = length_base[z]; 2354 if (length_extra[z]) len += zreceive(a, length_extra[z]); 2355 z = zhuffman_decode(a, &a->z_distance); 2356 if (z < 0) return e("bad huffman code","Corrupt PNG"); 2357 dist = dist_base[z]; 2358 if (dist_extra[z]) dist += zreceive(a, dist_extra[z]); 2359 if (a->zout - a->zout_start < dist) return e("bad dist","Corrupt PNG"); 2360 if (a->zout + len > a->zout_end) if (!expand(a, len)) return 0; 2361 p = (uint8 *) (a->zout - dist); 2362 while (len--) 2363 *a->zout++ = *p++; 2364 } 2365 } 2366} 2367 2368static int compute_huffman_codes(zbuf *a) 2369{ 2370 static uint8 length_dezigzag[19] = { 16,17,18,0,8,7,9,6,10,5,11,4,12,3,13,2,14,1,15 }; 2371 zhuffman z_codelength; 2372 uint8 lencodes[286+32+137];//padding for maximum single op 2373 uint8 codelength_sizes[19]; 2374 int i,n; 2375 2376 int hlit = zreceive(a,5) + 257; 2377 int hdist = zreceive(a,5) + 1; 2378 int hclen = zreceive(a,4) + 4; 2379 2380 memset(codelength_sizes, 0, sizeof(codelength_sizes)); 2381 for (i=0; i < hclen; ++i) { 2382 int s = zreceive(a,3); 2383 codelength_sizes[length_dezigzag[i]] = (uint8) s; 2384 } 2385 if (!zbuild_huffman(&z_codelength, codelength_sizes, 19)) return 0; 2386 2387 n = 0; 2388 while (n < hlit + hdist) { 2389 int c = zhuffman_decode(a, &z_codelength); 2390 assert(c >= 0 && c < 19); 2391 if (c < 16) 2392 lencodes[n++] = (uint8) c; 2393 else if (c == 16) { 2394 c = zreceive(a,2)+3; 2395 memset(lencodes+n, lencodes[n-1], c); 2396 n += c; 2397 } else if (c == 17) { 2398 c = zreceive(a,3)+3; 2399 memset(lencodes+n, 0, c); 2400 n += c; 2401 } else { 2402 assert(c == 18); 2403 c = zreceive(a,7)+11; 2404 memset(lencodes+n, 0, c); 2405 n += c; 2406 } 2407 } 2408 if (n != hlit+hdist) return e("bad codelengths","Corrupt PNG"); 2409 if (!zbuild_huffman(&a->z_length, lencodes, hlit)) return 0; 2410 if (!zbuild_huffman(&a->z_distance, lencodes+hlit, hdist)) return 0; 2411 return 1; 2412} 2413 2414static int parse_uncompressed_block(zbuf *a) 2415{ 2416 uint8 header[4]; 2417 int len,nlen,k; 2418 if (a->num_bits & 7) 2419 zreceive(a, a->num_bits & 7); // discard 2420 // drain the bit-packed data into header 2421 k = 0; 2422 while (a->num_bits > 0) { 2423 header[k++] = (uint8) (a->code_buffer & 255); // wtf this warns? 2424 a->code_buffer >>= 8; 2425 a->num_bits -= 8; 2426 } 2427 assert(a->num_bits == 0); 2428 // now fill header the normal way 2429 while (k < 4) 2430 header[k++] = (uint8) zget8(a); 2431 len = header[1] * 256 + header[0]; 2432 nlen = header[3] * 256 + header[2]; 2433 if (nlen != (len ^ 0xffff)) return e("zlib corrupt","Corrupt PNG"); 2434 if (a->zbuffer + len > a->zbuffer_end) return e("read past buffer","Corrupt PNG"); 2435 if (a->zout + len > a->zout_end) 2436 if (!expand(a, len)) return 0; 2437 memcpy(a->zout, a->zbuffer, len); 2438 a->zbuffer += len; 2439 a->zout += len; 2440 return 1; 2441} 2442 2443static int parse_zlib_header(zbuf *a) 2444{ 2445 int cmf = zget8(a); 2446 int cm = cmf & 15; 2447 /* int cinfo = cmf >> 4; */ 2448 int flg = zget8(a); 2449 if ((cmf*256+flg) % 31 != 0) return e("bad zlib header","Corrupt PNG"); // zlib spec 2450 if (flg & 32) return e("no preset dict","Corrupt PNG"); // preset dictionary not allowed in png 2451 if (cm != 8) return e("bad compression","Corrupt PNG"); // DEFLATE required for png 2452 // window = 1 << (8 + cinfo)... but who cares, we fully buffer output 2453 return 1; 2454} 2455 2456// @TODO: should statically initialize these for optimal thread safety 2457static uint8 default_length[288], default_distance[32]; 2458static void init_defaults(void) 2459{ 2460 int i; // use <= to match clearly with spec 2461 for (i=0; i <= 143; ++i) default_length[i] = 8; 2462 for ( ; i <= 255; ++i) default_length[i] = 9; 2463 for ( ; i <= 279; ++i) default_length[i] = 7; 2464 for ( ; i <= 287; ++i) default_length[i] = 8; 2465 2466 for (i=0; i <= 31; ++i) default_distance[i] = 5; 2467} 2468 2469int stbi_png_partial; // a quick hack to only allow decoding some of a PNG... I should implement real streaming support instead 2470static int parse_zlib(zbuf *a, int parse_header) 2471{ 2472 int final, type; 2473 if (parse_header) 2474 if (!parse_zlib_header(a)) return 0; 2475 a->num_bits = 0; 2476 a->code_buffer = 0; 2477 do { 2478 final = zreceive(a,1); 2479 type = zreceive(a,2); 2480 if (type == 0) { 2481 if (!parse_uncompressed_block(a)) return 0; 2482 } else if (type == 3) { 2483 return 0; 2484 } else { 2485 if (type == 1) { 2486 // use fixed code lengths 2487 if (!default_distance[31]) init_defaults(); 2488 if (!zbuild_huffman(&a->z_length , default_length , 288)) return 0; 2489 if (!zbuild_huffman(&a->z_distance, default_distance, 32)) return 0; 2490 } else { 2491 if (!compute_huffman_codes(a)) return 0; 2492 } 2493 if (!parse_huffman_block(a)) return 0; 2494 } 2495 if (stbi_png_partial && a->zout - a->zout_start > 65536) 2496 break; 2497 } while (!final); 2498 return 1; 2499} 2500 2501static int do_zlib(zbuf *a, char *obuf, int olen, int exp, int parse_header) 2502{ 2503 a->zout_start = obuf; 2504 a->zout = obuf; 2505 a->zout_end = obuf + olen; 2506 a->z_expandable = exp; 2507 2508 return parse_zlib(a, parse_header); 2509} 2510 2511char *stbi_zlib_decode_malloc_guesssize(const char * buffer, int len, int initial_size, int *outlen) 2512{ 2513 zbuf a; 2514 char *p = (char *) MALLOC(initial_size); 2515 if (p == NULL) return NULL; 2516 a.zbuffer = (uint8 const *) buffer; 2517 a.zbuffer_end = (uint8 const *) buffer + len; 2518 if (do_zlib(&a, p, initial_size, 1, 1)) { 2519 if (outlen) *outlen = (int) (a.zout - a.zout_start); 2520 return a.zout_start; 2521 } else { 2522 FREE(a.zout_start); 2523 return NULL; 2524 } 2525} 2526 2527char *stbi_zlib_decode_malloc(char const *buffer, int len, int *outlen) 2528{ 2529 return stbi_zlib_decode_malloc_guesssize(buffer, len, 16384, outlen); 2530} 2531 2532char *stbi_zlib_decode_malloc_guesssize_headerflag(const char *buffer, int len, int initial_size, int *outlen, int parse_header) 2533{ 2534 zbuf a; 2535 char *p = (char *) MALLOC(initial_size); 2536 if (p == NULL) return NULL; 2537 a.zbuffer = (uint8 const *) buffer; 2538 a.zbuffer_end = (uint8 const *) buffer + len; 2539 if (do_zlib(&a, p, initial_size, 1, parse_header)) { 2540 if (outlen) *outlen = (int) (a.zout - a.zout_start); 2541 return a.zout_start; 2542 } else { 2543 FREE(a.zout_start); 2544 return NULL; 2545 } 2546} 2547 2548int stbi_zlib_decode_buffer(char *obuffer, int olen, char const *ibuffer, int ilen) 2549{ 2550 zbuf a; 2551 a.zbuffer = (uint8 const *) ibuffer; 2552 a.zbuffer_end = (uint8 const *) ibuffer + ilen; 2553 if (do_zlib(&a, obuffer, olen, 0, 1)) 2554 return (int) (a.zout - a.zout_start); 2555 else 2556 return -1; 2557} 2558 2559char *stbi_zlib_decode_noheader_malloc(char const *buffer, int len, int *outlen) 2560{ 2561 zbuf a; 2562 char *p = (char *) MALLOC(16384); 2563 if (p == NULL) return NULL; 2564 a.zbuffer = (uint8 const *) buffer; 2565 a.zbuffer_end = (uint8 const *) buffer+len; 2566 if (do_zlib(&a, p, 16384, 1, 0)) { 2567 if (outlen) *outlen = (int) (a.zout - a.zout_start); 2568 return a.zout_start; 2569 } else { 2570 FREE(a.zout_start); 2571 return NULL; 2572 } 2573} 2574 2575int stbi_zlib_decode_noheader_buffer(char *obuffer, int olen, const char *ibuffer, int ilen) 2576{ 2577 zbuf a; 2578 a.zbuffer = (uint8 const *) ibuffer; 2579 a.zbuffer_end = (uint8 const *) ibuffer + ilen; 2580 if (do_zlib(&a, obuffer, olen, 0, 0)) 2581 return (int) (a.zout - a.zout_start); 2582 else 2583 return -1; 2584} 2585 2586// public domain "baseline" PNG decoder v0.10 Sean Barrett 2006-11-18 2587// simple implementation 2588// - only 8-bit samples 2589// - no CRC checking 2590// - allocates lots of intermediate memory 2591// - avoids problem of streaming data between subsystems 2592// - avoids explicit window management 2593// performance 2594// - uses stb_zlib, a PD zlib implementation with fast huffman decoding 2595 2596 2597typedef struct 2598{ 2599 uint32 length; 2600 uint32 type; 2601} chunk; 2602 2603#define PNG_TYPE(a,b,c,d) (((a) << 24) + ((b) << 16) + ((c) << 8) + (d)) 2604 2605static chunk get_chunk_header(stbi *s) 2606{ 2607 chunk c; 2608 c.length = get32(s); 2609 c.type = get32(s); 2610 return c; 2611} 2612 2613static int check_png_header(stbi *s) 2614{ 2615 static uint8 png_sig[8] = { 137,80,78,71,13,10,26,10 }; 2616 int i; 2617 for (i=0; i < 8; ++i) 2618 if (get8(s) != png_sig[i]) return e("bad png sig","Not a PNG"); 2619 return 1; 2620} 2621 2622typedef struct 2623{ 2624 stbi s; 2625 uint8 *idata, *expanded, *out; 2626} png; 2627 2628 2629enum { 2630 F_none=0, F_sub=1, F_up=2, F_avg=3, F_paeth=4, 2631 F_avg_first, F_paeth_first 2632}; 2633 2634static uint8 first_row_filter[5] = 2635{ 2636 F_none, F_sub, F_none, F_avg_first, F_paeth_first 2637}; 2638 2639static int paeth(int a, int b, int c) 2640{ 2641 int p = a + b - c; 2642 int pa = abs(p-a); 2643 int pb = abs(p-b); 2644 int pc = abs(p-c); 2645 if (pa <= pb && pa <= pc) return a; 2646 if (pb <= pc) return b; 2647 return c; 2648} 2649 2650// create the png data from post-deflated data 2651static int create_png_image_raw(png *a, uint8 *raw, uint32 raw_len, int out_n, uint32 x, uint32 y) 2652{ 2653 stbi *s = &a->s; 2654 uint32 i,j,stride = x*out_n; 2655 int k; 2656 int img_n = s->img_n; // copy it into a local for later 2657 assert(out_n == s->img_n || out_n == s->img_n+1); 2658 if (stbi_png_partial) y = 1; 2659 a->out = (uint8 *) MALLOC(x * y * out_n); 2660 if (!a->out) return e("outofmem", "Out of memory"); 2661 if (!stbi_png_partial) { 2662 if (s->img_x == x && s->img_y == y) { 2663 if (raw_len != (img_n * x + 1) * y) return e("not enough pixels","Corrupt PNG"); 2664 } else { // interlaced: 2665 if (raw_len < (img_n * x + 1) * y) return e("not enough pixels","Corrupt PNG"); 2666 } 2667 } 2668 for (j=0; j < y; ++j) { 2669 uint8 *cur = a->out + stride*j; 2670 uint8 *prior = cur - stride; 2671 int filter = *raw++; 2672 if (filter > 4) return e("invalid filter","Corrupt PNG"); 2673 // if first row, use special filter that doesn't sample previous row 2674 if (j == 0) filter = first_row_filter[filter]; 2675 // handle first pixel explicitly 2676 for (k=0; k < img_n; ++k) { 2677 switch (filter) { 2678 case F_none : cur[k] = raw[k]; break; 2679 case F_sub : cur[k] = raw[k]; break; 2680 case F_up : cur[k] = raw[k] + prior[k]; break; 2681 case F_avg : cur[k] = raw[k] + (prior[k]>>1); break; 2682 case F_paeth : cur[k] = (uint8) (raw[k] + paeth(0,prior[k],0)); break; 2683 case F_avg_first : cur[k] = raw[k]; break; 2684 case F_paeth_first: cur[k] = raw[k]; break; 2685 } 2686 } 2687 if (img_n != out_n) cur[img_n] = 255; 2688 raw += img_n; 2689 cur += out_n; 2690 prior += out_n; 2691 // this is a little gross, so that we don't switch per-pixel or per-component 2692 if (img_n == out_n) { 2693 #define CASE(f) \ 2694 case f: \ 2695 for (i=x-1; i >= 1; --i, raw+=img_n,cur+=img_n,prior+=img_n) \ 2696 for (k=0; k < img_n; ++k) 2697 switch (filter) { 2698 CASE(F_none) cur[k] = raw[k]; break; 2699 CASE(F_sub) cur[k] = raw[k] + cur[k-img_n]; break; 2700 CASE(F_up) cur[k] = raw[k] + prior[k]; break; 2701 CASE(F_avg) cur[k] = raw[k] + ((prior[k] + cur[k-img_n])>>1); break; 2702 CASE(F_paeth) cur[k] = (uint8) (raw[k] + paeth(cur[k-img_n],prior[k],prior[k-img_n])); break; 2703 CASE(F_avg_first) cur[k] = raw[k] + (cur[k-img_n] >> 1); break; 2704 CASE(F_paeth_first) cur[k] = (uint8) (raw[k] + paeth(cur[k-img_n],0,0)); break; 2705 } 2706 #undef CASE 2707 } else { 2708 assert(img_n+1 == out_n); 2709 #define CASE(f) \ 2710 case f: \ 2711 for (i=x-1; i >= 1; --i, cur[img_n]=255,raw+=img_n,cur+=out_n,prior+=out_n) \ 2712 for (k=0; k < img_n; ++k) 2713 switch (filter) { 2714 CASE(F_none) cur[k] = raw[k]; break; 2715 CASE(F_sub) cur[k] = raw[k] + cur[k-out_n]; break; 2716 CASE(F_up) cur[k] = raw[k] + prior[k]; break; 2717 CASE(F_avg) cur[k] = raw[k] + ((prior[k] + cur[k-out_n])>>1); break; 2718 CASE(F_paeth) cur[k] = (uint8) (raw[k] + paeth(cur[k-out_n],prior[k],prior[k-out_n])); break; 2719 CASE(F_avg_first) cur[k] = raw[k] + (cur[k-out_n] >> 1); break; 2720 CASE(F_paeth_first) cur[k] = (uint8) (raw[k] + paeth(cur[k-out_n],0,0)); break; 2721 } 2722 #undef CASE 2723 } 2724 } 2725 return 1; 2726} 2727 2728static int create_png_image(png *a, uint8 *raw, uint32 raw_len, int out_n, int interlaced) 2729{ 2730 uint8 *final; 2731 int p; 2732 int save; 2733 if (!interlaced) 2734 return create_png_image_raw(a, raw, raw_len, out_n, a->s.img_x, a->s.img_y); 2735 save = stbi_png_partial; 2736 stbi_png_partial = 0; 2737 2738 // de-interlacing 2739 final = (uint8 *) MALLOC(a->s.img_x * a->s.img_y * out_n); 2740 for (p=0; p < 7; ++p) { 2741 int xorig[] = { 0,4,0,2,0,1,0 }; 2742 int yorig[] = { 0,0,4,0,2,0,1 }; 2743 int xspc[] = { 8,8,4,4,2,2,1 }; 2744 int yspc[] = { 8,8,8,4,4,2,2 }; 2745 int i,j,x,y; 2746 // pass1_x[4] = 0, pass1_x[5] = 1, pass1_x[12] = 1 2747 x = (a->s.img_x - xorig[p] + xspc[p]-1) / xspc[p]; 2748 y = (a->s.img_y - yorig[p] + yspc[p]-1) / yspc[p]; 2749 if (x && y) { 2750 if (!create_png_image_raw(a, raw, raw_len, out_n, x, y)) { 2751 FREE(final); 2752 return 0; 2753 } 2754 for (j=0; j < y; ++j) 2755 for (i=0; i < x; ++i) 2756 memcpy(final + (j*yspc[p]+yorig[p])*a->s.img_x*out_n + (i*xspc[p]+xorig[p])*out_n, 2757 a->out + (j*x+i)*out_n, out_n); 2758 FREE(a->out); 2759 raw += (x*out_n+1)*y; 2760 raw_len -= (x*out_n+1)*y; 2761 } 2762 } 2763 a->out = final; 2764 2765 stbi_png_partial = save; 2766 return 1; 2767} 2768 2769static int compute_transparency(png *z, uint8 tc[3], int out_n) 2770{ 2771 stbi *s = &z->s; 2772 uint32 i, pixel_count = s->img_x * s->img_y; 2773 uint8 *p = z->out; 2774 2775 // compute color-based transparency, assuming we've 2776 // already got 255 as the alpha value in the output 2777 assert(out_n == 2 || out_n == 4); 2778 2779 if (out_n == 2) { 2780 for (i=0; i < pixel_count; ++i) { 2781 p[1] = (p[0] == tc[0] ? 0 : 255); 2782 p += 2; 2783 } 2784 } else { 2785 for (i=0; i < pixel_count; ++i) { 2786 if (p[0] == tc[0] && p[1] == tc[1] && p[2] == tc[2]) 2787 p[3] = 0; 2788 p += 4; 2789 } 2790 } 2791 return 1; 2792} 2793 2794static int expand_palette(png *a, uint8 *palette, int len, int pal_img_n) 2795{ 2796 uint32 i, pixel_count = a->s.img_x * a->s.img_y; 2797 uint8 *p, *temp_out, *orig = a->out; 2798 2799 p = (uint8 *) MALLOC(pixel_count * pal_img_n); 2800 if (p == NULL) return e("outofmem", "Out of memory"); 2801 2802 // between here and FREE(out) below, exitting would leak 2803 temp_out = p; 2804 2805 if (pal_img_n == 3) { 2806 for (i=0; i < pixel_count; ++i) { 2807 int n = orig[i]*4; 2808 p[0] = palette[n ]; 2809 p[1] = palette[n+1]; 2810 p[2] = palette[n+2]; 2811 p += 3; 2812 } 2813 } else { 2814 for (i=0; i < pixel_count; ++i) { 2815 int n = orig[i]*4; 2816 p[0] = palette[n ]; 2817 p[1] = palette[n+1]; 2818 p[2] = palette[n+2]; 2819 p[3] = palette[n+3]; 2820 p += 4; 2821 } 2822 } 2823 FREE(a->out); 2824 a->out = temp_out; 2825 2826 STBI_NOTUSED(len); 2827 2828 return 1; 2829} 2830 2831static int stbi_unpremultiply_on_load = 0; 2832static int stbi_de_iphone_flag = 0; 2833 2834void stbi_set_unpremultiply_on_load(int flag_true_if_should_unpremultiply) 2835{ 2836 stbi_unpremultiply_on_load = flag_true_if_should_unpremultiply; 2837} 2838void stbi_convert_iphone_png_to_rgb(int flag_true_if_should_convert) 2839{ 2840 stbi_de_iphone_flag = flag_true_if_should_convert; 2841} 2842 2843static void stbi_de_iphone(png *z) 2844{ 2845 stbi *s = &z->s; 2846 uint32 i, pixel_count = s->img_x * s->img_y; 2847 uint8 *p = z->out; 2848 2849 if (s->img_out_n == 3) { // convert bgr to rgb 2850 for (i=0; i < pixel_count; ++i) { 2851 uint8 t = p[0]; 2852 p[0] = p[2]; 2853 p[2] = t; 2854 p += 3; 2855 } 2856 } else { 2857 assert(s->img_out_n == 4); 2858 if (stbi_unpremultiply_on_load) { 2859 // convert bgr to rgb and unpremultiply 2860 for (i=0; i < pixel_count; ++i) { 2861 uint8 a = p[3]; 2862 uint8 t = p[0]; 2863 if (a) { 2864 p[0] = p[2] * 255 / a; 2865 p[1] = p[1] * 255 / a; 2866 p[2] = t * 255 / a; 2867 } else { 2868 p[0] = p[2]; 2869 p[2] = t; 2870 } 2871 p += 4; 2872 } 2873 } else { 2874 // convert bgr to rgb 2875 for (i=0; i < pixel_count; ++i) { 2876 uint8 t = p[0]; 2877 p[0] = p[2]; 2878 p[2] = t; 2879 p += 4; 2880 } 2881 } 2882 } 2883} 2884 2885static int parse_png_file(png *z, int scan, int req_comp) 2886{ 2887 uint8 palette[1024], pal_img_n=0; 2888 uint8 has_trans=0, tc[3]; 2889 uint32 ioff=0, idata_limit=0, i, pal_len=0; 2890 int first=1,k,interlace=0, iphone=0; 2891 stbi *s = &z->s; 2892 2893 if (!check_png_header(s)) return 0; 2894 2895 if (scan == SCAN_type) return 1; 2896 2897 for (;;) { 2898 chunk c = get_chunk_header(s); 2899 switch (c.type) { 2900 case PNG_TYPE('C','g','B','I'): 2901 iphone = stbi_de_iphone_flag; 2902 skip(s, c.length); 2903 break; 2904 case PNG_TYPE('I','H','D','R'): { 2905 int depth,color,comp,filter; 2906 if (!first) return e("multiple IHDR","Corrupt PNG"); 2907 first = 0; 2908 if (c.length != 13) return e("bad IHDR len","Corrupt PNG"); 2909 s->img_x = get32(s); if (s->img_x > (1 << 24)) return e("too large","Very large image (corrupt?)"); 2910 s->img_y = get32(s); if (s->img_y > (1 << 24)) return e("too large","Very large image (corrupt?)"); 2911 depth = get8(s); if (depth != 8) return e("8bit only","PNG not supported: 8-bit only"); 2912 color = get8(s); if (color > 6) return e("bad ctype","Corrupt PNG"); 2913 if (color == 3) pal_img_n = 3; else if (color & 1) return e("bad ctype","Corrupt PNG"); 2914 comp = get8(s); if (comp) return e("bad comp method","Corrupt PNG"); 2915 filter= get8(s); if (filter) return e("bad filter method","Corrupt PNG"); 2916 interlace = get8(s); if (interlace>1) return e("bad interlace method","Corrupt PNG"); 2917 if (!s->img_x || !s->img_y) return e("0-pixel image","Corrupt PNG"); 2918 if (!pal_img_n) { 2919 s->img_n = (color & 2 ? 3 : 1) + (color & 4 ? 1 : 0); 2920 if ((1 << 30) / s->img_x / s->img_n < s->img_y) return e("too large", "Image too large to decode"); 2921 if (scan == SCAN_header) return 1; 2922 } else { 2923 // if paletted, then pal_n is our final components, and 2924 // img_n is # components to decompress/filter. 2925 s->img_n = 1; 2926 if ((1 << 30) / s->img_x / 4 < s->img_y) return e("too large","Corrupt PNG"); 2927 // if SCAN_header, have to scan to see if we have a tRNS 2928 } 2929 break; 2930 } 2931 2932 case PNG_TYPE('P','L','T','E'): { 2933 if (first) return e("first not IHDR", "Corrupt PNG"); 2934 if (c.length > 256*3) return e("invalid PLTE","Corrupt PNG"); 2935 pal_len = c.length / 3; 2936 if (pal_len * 3 != c.length) return e("invalid PLTE","Corrupt PNG"); 2937 for (i=0; i < pal_len; ++i) { 2938 palette[i*4+0] = get8u(s); 2939 palette[i*4+1] = get8u(s); 2940 palette[i*4+2] = get8u(s); 2941 palette[i*4+3] = 255; 2942 } 2943 break; 2944 } 2945 2946 case PNG_TYPE('t','R','N','S'): { 2947 if (first) return e("first not IHDR", "Corrupt PNG"); 2948 if (z->idata) return e("tRNS after IDAT","Corrupt PNG"); 2949 if (pal_img_n) { 2950 if (scan == SCAN_header) { s->img_n = 4; return 1; } 2951 if (pal_len == 0) return e("tRNS before PLTE","Corrupt PNG"); 2952 if (c.length > pal_len) return e("bad tRNS len","Corrupt PNG"); 2953 pal_img_n = 4; 2954 for (i=0; i < c.length; ++i) 2955 palette[i*4+3] = get8u(s); 2956 } else { 2957 if (!(s->img_n & 1)) return e("tRNS with alpha","Corrupt PNG"); 2958 if (c.length != (uint32) s->img_n*2) return e("bad tRNS len","Corrupt PNG"); 2959 has_trans = 1; 2960 for (k=0; k < s->img_n; ++k) 2961 tc[k] = (uint8) get16(s); // non 8-bit images will be larger 2962 } 2963 break; 2964 } 2965 2966 case PNG_TYPE('I','D','A','T'): { 2967 if (first) return e("first not IHDR", "Corrupt PNG"); 2968 if (pal_img_n && !pal_len) return e("no PLTE","Corrupt PNG"); 2969 if (scan == SCAN_header) { s->img_n = pal_img_n; return 1; } 2970 if (ioff + c.length > idata_limit) { 2971 uint8 *p; 2972 if (idata_limit == 0) idata_limit = c.length > 4096 ? c.length : 4096; 2973 while (ioff + c.length > idata_limit) 2974 idata_limit *= 2; 2975 p = (uint8 *) REALLOC(z->idata, idata_limit); if (p == NULL) return e("outofmem", "Out of memory"); 2976 z->idata = p; 2977 } 2978 if (!getn(s, z->idata+ioff,c.length)) return e("outofdata","Corrupt PNG"); 2979 ioff += c.length; 2980 break; 2981 } 2982 2983 case PNG_TYPE('I','E','N','D'): { 2984 uint32 raw_len; 2985 if (first) return e("first not IHDR", "Corrupt PNG"); 2986 if (scan != SCAN_load) return 1; 2987 if (z->idata == NULL) return e("no IDAT","Corrupt PNG"); 2988 z->expanded = (uint8 *) stbi_zlib_decode_malloc_guesssize_headerflag((char *) z->idata, ioff, 16384, (int *) &raw_len, !iphone); 2989 if (z->expanded == NULL) return 0; // zlib should set error 2990 FREE(z->idata); z->idata = NULL; 2991 if ((req_comp == s->img_n+1 && req_comp != 3 && !pal_img_n) || has_trans) 2992 s->img_out_n = s->img_n+1; 2993 else 2994 s->img_out_n = s->img_n; 2995 if (!create_png_image(z, z->expanded, raw_len, s->img_out_n, interlace)) return 0; 2996 if (has_trans) 2997 if (!compute_transparency(z, tc, s->img_out_n)) return 0; 2998 if (iphone && s->img_out_n > 2) 2999 stbi_de_iphone(z); 3000 if (pal_img_n) { 3001 // pal_img_n == 3 or 4 3002 s->img_n = pal_img_n; // record the actual colors we had 3003 s->img_out_n = pal_img_n; 3004 if (req_comp >= 3) s->img_out_n = req_comp; 3005 if (!expand_palette(z, palette, pal_len, s->img_out_n)) 3006 return 0; 3007 } 3008 FREE(z->expanded); z->expanded = NULL; 3009 return 1; 3010 } 3011 3012 default: 3013 // if critical, fail 3014 if (first) return e("first not IHDR", "Corrupt PNG"); 3015 if ((c.type & (1 << 29)) == 0) { 3016 #ifndef STBI_NO_FAILURE_STRINGS 3017 // not threadsafe 3018 static char invalid_chunk[] = "XXXX chunk not known"; 3019 invalid_chunk[0] = (uint8) (c.type >> 24); 3020 invalid_chunk[1] = (uint8) (c.type >> 16); 3021 invalid_chunk[2] = (uint8) (c.type >> 8); 3022 invalid_chunk[3] = (uint8) (c.type >> 0); 3023 #endif 3024 return e(invalid_chunk, "PNG not supported: unknown chunk type"); 3025 } 3026 skip(s, c.length); 3027 break; 3028 } 3029 // end of chunk, read and skip CRC 3030 get32(s); 3031 } 3032} 3033 3034static unsigned char *do_png(png *p, int *x, int *y, int *n, int req_comp) 3035{ 3036 unsigned char *result=NULL; 3037 p->expanded = NULL; 3038 p->idata = NULL; 3039 p->out = NULL; 3040 if (req_comp < 0 || req_comp > 4) return epuc("bad req_comp", "Internal error"); 3041 if (parse_png_file(p, SCAN_load, req_comp)) { 3042 result = p->out; 3043 p->out = NULL; 3044 if (req_comp && req_comp != p->s.img_out_n) { 3045 result = convert_format(result, p->s.img_out_n, req_comp, p->s.img_x, p->s.img_y); 3046 p->s.img_out_n = req_comp; 3047 if (result == NULL) return result; 3048 } 3049 *x = p->s.img_x; 3050 *y = p->s.img_y; 3051 if (n) *n = p->s.img_n; 3052 } 3053 FREE(p->out); p->out = NULL; 3054 FREE(p->expanded); p->expanded = NULL; 3055 FREE(p->idata); p->idata = NULL; 3056 3057 return result; 3058} 3059 3060#ifndef STBI_NO_STDIO 3061unsigned char *stbi_png_load_from_file(FILE *f, int *x, int *y, int *comp, int req_comp) 3062{ 3063 png p; 3064 start_file(&p.s, f); 3065 return do_png(&p, x,y,comp,req_comp); 3066} 3067 3068unsigned char *stbi_png_load(char const *filename, int *x, int *y, int *comp, int req_comp) 3069{ 3070 unsigned char *data; 3071 FILE *f = fopen(filename, "rb"); 3072 if (!f) return NULL; 3073 data = stbi_png_load_from_file(f,x,y,comp,req_comp); 3074 fclose(f); 3075 return data; 3076} 3077#endif 3078 3079unsigned char *stbi_png_load_from_memory(stbi_uc const *buffer, int len, int *x, int *y, int *comp, int req_comp) 3080{ 3081 png p; 3082 start_mem(&p.s, buffer,len); 3083 return do_png(&p, x,y,comp,req_comp); 3084} 3085 3086#ifndef STBI_NO_STDIO 3087int stbi_png_test_file(FILE *f) 3088{ 3089 png p; 3090 int n,r; 3091 n = ftell(f); 3092 start_file(&p.s, f); 3093 r = parse_png_file(&p, SCAN_type,STBI_default); 3094 fseek(f,n,SEEK_SET); 3095 return r; 3096} 3097#endif 3098 3099int stbi_png_test_memory(stbi_uc const *buffer, int len) 3100{ 3101 png p; 3102 start_mem(&p.s, buffer, len); 3103 return parse_png_file(&p, SCAN_type,STBI_default); 3104} 3105 3106static int stbi_png_info_raw(png *p, int *x, int *y, int *comp) 3107{ 3108 if (!parse_png_file(p, SCAN_header, 0)) 3109 return 0; 3110 if (x) *x = p->s.img_x; 3111 if (y) *y = p->s.img_y; 3112 if (comp) *comp = p->s.img_n; 3113 return 1; 3114} 3115 3116#ifndef STBI_NO_STDIO 3117int stbi_png_info (char const *filename, int *x, int *y, int *comp) 3118{ 3119 int res; 3120 FILE *f = fopen(filename, "rb"); 3121 if (!f) return 0; 3122 res = stbi_png_info_from_file(f, x, y, comp); 3123 fclose(f); 3124 return res; 3125} 3126 3127int stbi_png_info_from_file(FILE *f, int *x, int *y, int *comp) 3128{ 3129 png p; 3130 int res; 3131 long n = ftell(f); 3132 start_file(&p.s, f); 3133 res = stbi_png_info_raw(&p, x, y, comp); 3134 fseek(f, n, SEEK_SET); 3135 return res; 3136} 3137#endif // !STBI_NO_STDIO 3138 3139int stbi_png_info_from_memory(stbi_uc const *buffer, int len, int *x, int *y, int *comp) 3140{ 3141 png p; 3142 start_mem(&p.s, buffer, len); 3143 return stbi_png_info_raw(&p, x, y, comp); 3144} 3145 3146// Microsoft/Windows BMP image 3147 3148static int bmp_test(stbi *s) 3149{ 3150 int sz; 3151 if (get8(s) != 'B') return 0; 3152 if (get8(s) != 'M') return 0; 3153 get32le(s); // discard filesize 3154 get16le(s); // discard reserved 3155 get16le(s); // discard reserved 3156 get32le(s); // discard data offset 3157 sz = get32le(s); 3158 if (sz == 12 || sz == 40 || sz == 56 || sz == 108) return 1; 3159 return 0; 3160} 3161 3162#ifndef STBI_NO_STDIO 3163int stbi_bmp_test_file (FILE *f) 3164{ 3165 stbi s; 3166 int r,n = ftell(f); 3167 start_file(&s,f); 3168 r = bmp_test(&s); 3169 fseek(f,n,SEEK_SET); 3170 return r; 3171} 3172#endif 3173 3174int stbi_bmp_test_memory (stbi_uc const *buffer, int len) 3175{ 3176 stbi s; 3177 start_mem(&s, buffer, len); 3178 return bmp_test(&s); 3179} 3180 3181// returns 0..31 for the highest set bit 3182static int high_bit(unsigned int z) 3183{ 3184 int n=0; 3185 if (z == 0) return -1; 3186 if (z >= 0x10000) n += 16, z >>= 16; 3187 if (z >= 0x00100) n += 8, z >>= 8; 3188 if (z >= 0x00010) n += 4, z >>= 4; 3189 if (z >= 0x00004) n += 2, z >>= 2; 3190 if (z >= 0x00002) n += 1, z >>= 1; 3191 return n; 3192} 3193 3194static int bitcount(unsigned int a) 3195{ 3196 a = (a & 0x55555555) + ((a >> 1) & 0x55555555); // max 2 3197 a = (a & 0x33333333) + ((a >> 2) & 0x33333333); // max 4 3198 a = (a + (a >> 4)) & 0x0f0f0f0f; // max 8 per 4, now 8 bits 3199 a = (a + (a >> 8)); // max 16 per 8 bits 3200 a = (a + (a >> 16)); // max 32 per 8 bits 3201 return a & 0xff; 3202} 3203 3204static int shiftsigned(int v, int shift, int bits) 3205{ 3206 int result; 3207 int z=0; 3208 3209 if (shift < 0) v <<= -shift; 3210 else v >>= shift; 3211 result = v; 3212 3213 z = bits; 3214 while (z < 8) { 3215 result += v >> z; 3216 z += bits; 3217 } 3218 return result; 3219} 3220 3221static stbi_uc *bmp_load(stbi *s, int *x, int *y, int *comp, int req_comp) 3222{ 3223 uint8 *out; 3224 unsigned int mr=0,mg=0,mb=0,ma=0, fake_a=0; 3225 stbi_uc pal[256][4]; 3226 int psize=0,i,j,compress=0,width; 3227 int bpp, flip_vertically, pad, target, offset, hsz; 3228 if (get8(s) != 'B' || get8(s) != 'M') return epuc("not BMP", "Corrupt BMP"); 3229 get32le(s); // discard filesize 3230 get16le(s); // discard reserved 3231 get16le(s); // discard reserved 3232 offset = get32le(s); 3233 hsz = get32le(s); 3234 if (hsz != 12 && hsz != 40 && hsz != 56 && hsz != 108) return epuc("unknown BMP", "BMP type not supported: unknown"); 3235 if (hsz == 12) { 3236 s->img_x = get16le(s); 3237 s->img_y = get16le(s); 3238 } else { 3239 s->img_x = get32le(s); 3240 s->img_y = get32le(s); 3241 } 3242 if (get16le(s) != 1) return epuc("bad BMP", "bad BMP"); 3243 bpp = get16le(s); 3244 if (bpp == 1) return epuc("monochrome", "BMP type not supported: 1-bit"); 3245 flip_vertically = ((int) s->img_y) > 0; 3246 s->img_y = abs((int) s->img_y); 3247 if (hsz == 12) { 3248 if (bpp < 24) 3249 psize = (offset - 14 - 24) / 3; 3250 } else { 3251 compress = get32le(s); 3252 if (compress == 1 || compress == 2) return epuc("BMP RLE", "BMP type not supported: RLE"); 3253 get32le(s); // discard sizeof 3254 get32le(s); // discard hres 3255 get32le(s); // discard vres 3256 get32le(s); // discard colorsused 3257 get32le(s); // discard max important 3258 if (hsz == 40 || hsz == 56) { 3259 if (hsz == 56) { 3260 get32le(s); 3261 get32le(s); 3262 get32le(s); 3263 get32le(s); 3264 } 3265 if (bpp == 16 || bpp == 32) { 3266 mr = mg = mb = 0; 3267 if (compress == 0) { 3268 if (bpp == 32) { 3269 mr = 0xffu << 16; 3270 mg = 0xffu << 8; 3271 mb = 0xffu << 0; 3272 ma = 0xffu << 24; 3273 fake_a = 1; // @TODO: check for cases like alpha value is all 0 and switch it to 255 3274 } else { 3275 mr = 31u << 10; 3276 mg = 31u << 5; 3277 mb = 31u << 0; 3278 } 3279 } else if (compress == 3) { 3280 mr = get32le(s); 3281 mg = get32le(s); 3282 mb = get32le(s); 3283 // not documented, but generated by photoshop and handled by mspaint 3284 if (mr == mg && mg == mb) { 3285 // ?!?!? 3286 return epuc("bad BMP", "bad BMP"); 3287 } 3288 } else 3289 return epuc("bad BMP", "bad BMP"); 3290 } 3291 } else { 3292 assert(hsz == 108); 3293 mr = get32le(s); 3294 mg = get32le(s); 3295 mb = get32le(s); 3296 ma = get32le(s); 3297 get32le(s); // discard color space 3298 for (i=0; i < 12; ++i) 3299 get32le(s); // discard color space parameters 3300 } 3301 if (bpp < 16) 3302 psize = (offset - 14 - hsz) >> 2; 3303 } 3304 s->img_n = ma ? 4 : 3; 3305 if (req_comp && req_comp >= 3) // we can directly decode 3 or 4 3306 target = req_comp; 3307 else 3308 target = s->img_n; // if they want monochrome, we'll post-convert 3309 out = (stbi_uc *) MALLOC(target * s->img_x * s->img_y); 3310 if (!out) return epuc("outofmem", "Out of memory"); 3311 if (bpp < 16) { 3312 int z=0; 3313 if (psize == 0 || psize > 256) { FREE(out); return epuc("invalid", "Corrupt BMP"); } 3314 for (i=0; i < psize; ++i) { 3315 pal[i][2] = get8u(s); 3316 pal[i][1] = get8u(s); 3317 pal[i][0] = get8u(s); 3318 if (hsz != 12) get8(s); 3319 pal[i][3] = 255; 3320 } 3321 skip(s, offset - 14 - hsz - psize * (hsz == 12 ? 3 : 4)); 3322 if (bpp == 4) width = (s->img_x + 1) >> 1; 3323 else if (bpp == 8) width = s->img_x; 3324 else { FREE(out); return epuc("bad bpp", "Corrupt BMP"); } 3325 pad = (-width)&3; 3326 for (j=0; j < (int) s->img_y; ++j) { 3327 for (i=0; i < (int) s->img_x; i += 2) { 3328 int v=get8(s),v2=0; 3329 if (bpp == 4) { 3330 v2 = v & 15; 3331 v >>= 4; 3332 } 3333 out[z++] = pal[v][0]; 3334 out[z++] = pal[v][1]; 3335 out[z++] = pal[v][2]; 3336 if (target == 4) out[z++] = 255; 3337 if (i+1 == (int) s->img_x) break; 3338 v = (bpp == 8) ? get8(s) : v2; 3339 out[z++] = pal[v][0]; 3340 out[z++] = pal[v][1]; 3341 out[z++] = pal[v][2]; 3342 if (target == 4) out[z++] = 255; 3343 } 3344 skip(s, pad); 3345 } 3346 } else { 3347 int rshift=0,gshift=0,bshift=0,ashift=0,rcount=0,gcount=0,bcount=0,acount=0; 3348 int z = 0; 3349 int easy=0; 3350 skip(s, offset - 14 - hsz); 3351 if (bpp == 24) width = 3 * s->img_x; 3352 else if (bpp == 16) width = 2*s->img_x; 3353 else /* bpp = 32 and pad = 0 */ width=0; 3354 pad = (-width) & 3; 3355 if (bpp == 24) { 3356 easy = 1; 3357 } else if (bpp == 32) { 3358 if (mb == 0xff && mg == 0xff00 && mr == 0xff000000 && ma == 0xff000000) 3359 easy = 2; 3360 } 3361 if (!easy) { 3362 if (!mr || !mg || !mb) return epuc("bad masks", "Corrupt BMP"); 3363 // right shift amt to put high bit in position #7 3364 rshift = high_bit(mr)-7; rcount = bitcount(mr); 3365 gshift = high_bit(mg)-7; gcount = bitcount(mr); 3366 bshift = high_bit(mb)-7; bcount = bitcount(mr); 3367 ashift = high_bit(ma)-7; acount = bitcount(mr); 3368 } 3369 for (j=0; j < (int) s->img_y; ++j) { 3370 if (easy) { 3371 for (i=0; i < (int) s->img_x; ++i) { 3372 int a; 3373 out[z+2] = get8u(s); 3374 out[z+1] = get8u(s); 3375 out[z+0] = get8u(s); 3376 z += 3; 3377 a = (easy == 2 ? get8(s) : 255); 3378 if (target == 4) out[z++] = (uint8) a; 3379 } 3380 } else { 3381 for (i=0; i < (int) s->img_x; ++i) { 3382 uint32 v = (bpp == 16 ? get16le(s) : get32le(s)); 3383 int a; 3384 out[z++] = (uint8) shiftsigned(v & mr, rshift, rcount); 3385 out[z++] = (uint8) shiftsigned(v & mg, gshift, gcount); 3386 out[z++] = (uint8) shiftsigned(v & mb, bshift, bcount); 3387 a = (ma ? shiftsigned(v & ma, ashift, acount) : 255); 3388 if (target == 4) out[z++] = (uint8) a; 3389 } 3390 } 3391 skip(s, pad); 3392 } 3393 } 3394 if (flip_vertically) { 3395 stbi_uc t; 3396 for (j=0; j < (int) s->img_y>>1; ++j) { 3397 stbi_uc *p1 = out + j *s->img_x*target; 3398 stbi_uc *p2 = out + (s->img_y-1-j)*s->img_x*target; 3399 for (i=0; i < (int) s->img_x*target; ++i) { 3400 t = p1[i], p1[i] = p2[i], p2[i] = t; 3401 } 3402 } 3403 } 3404 3405 if (req_comp && req_comp != target) { 3406 out = convert_format(out, target, req_comp, s->img_x, s->img_y); 3407 if (out == NULL) return out; // convert_format frees input on failure 3408 } 3409 3410 *x = s->img_x; 3411 *y = s->img_y; 3412 if (comp) *comp = target; 3413 return out; 3414} 3415 3416#ifndef STBI_NO_STDIO 3417stbi_uc *stbi_bmp_load (char const *filename, int *x, int *y, int *comp, int req_comp) 3418{ 3419 stbi_uc *data; 3420 FILE *f = fopen(filename, "rb"); 3421 if (!f) return NULL; 3422 data = stbi_bmp_load_from_file(f, x,y,comp,req_comp); 3423 fclose(f); 3424 return data; 3425} 3426 3427stbi_uc *stbi_bmp_load_from_file (FILE *f, int *x, int *y, int *comp, int req_comp) 3428{ 3429 stbi s; 3430 start_file(&s, f); 3431 return bmp_load(&s, x,y,comp,req_comp); 3432} 3433#endif 3434 3435stbi_uc *stbi_bmp_load_from_memory (stbi_uc const *buffer, int len, int *x, int *y, int *comp, int req_comp) 3436{ 3437 stbi s; 3438 start_mem(&s, buffer, len); 3439 return bmp_load(&s, x,y,comp,req_comp); 3440} 3441 3442// Targa Truevision - TGA 3443// by Jonathan Dummer 3444 3445static int tga_info(stbi *s, int *x, int *y, int *comp) 3446{ 3447 int tga_w, tga_h, tga_comp; 3448 int sz; 3449 get8u(s); // discard Offset 3450 sz = get8u(s); // color type 3451 if( sz > 1 ) return 0; // only RGB or indexed allowed 3452 sz = get8u(s); // image type 3453 // only RGB or grey allowed, +/- RLE 3454 if ((sz != 1) && (sz != 2) && (sz != 3) && (sz != 9) && (sz != 10) && (sz != 11)) return 0; 3455 get16le(s); // discard palette start 3456 get16le(s); // discard palette length 3457 get8(s); // discard bits per palette color entry 3458 get16le(s); // discard x origin 3459 get16le(s); // discard y origin 3460 tga_w = get16le(s); 3461 if( tga_w < 1 ) return 0; // test width 3462 tga_h = get16le(s); 3463 if( tga_h < 1 ) return 0; // test height 3464 sz = get8(s); // bits per pixel 3465 // only RGB or RGBA or grey allowed 3466 if ((sz != 8) && (sz != 16) && (sz != 24) && (sz != 32)) return 0; 3467 tga_comp = sz; 3468 if (x) *x = tga_w; 3469 if (y) *y = tga_h; 3470 if (comp) *comp = tga_comp / 8; 3471 return 1; // seems to have passed everything 3472} 3473 3474#ifndef STBI_NO_STDIO 3475int stbi_tga_info_from_file(FILE *f, int *x, int *y, int *comp) 3476{ 3477 stbi s; 3478 int r; 3479 long n = ftell(f); 3480 start_file(&s, f); 3481 r = tga_info(&s, x, y, comp); 3482 fseek(f, n, SEEK_SET); 3483 return r; 3484} 3485#endif 3486 3487int stbi_tga_info_from_memory(stbi_uc const *buffer, int len, int *x, int *y, int *comp) 3488{ 3489 stbi s; 3490 start_mem(&s, buffer, len); 3491 return tga_info(&s, x, y, comp); 3492} 3493 3494static int tga_test(stbi *s) 3495{ 3496 int sz; 3497 get8u(s); // discard Offset 3498 sz = get8u(s); // color type 3499 if ( sz > 1 ) return 0; // only RGB or indexed allowed 3500 sz = get8u(s); // image type 3501 if ( (sz != 1) && (sz != 2) && (sz != 3) && (sz != 9) && (sz != 10) && (sz != 11) ) return 0; // only RGB or grey allowed, +/- RLE 3502 get16(s); // discard palette start 3503 get16(s); // discard palette length 3504 get8(s); // discard bits per palette color entry 3505 get16(s); // discard x origin 3506 get16(s); // discard y origin 3507 if ( get16(s) < 1 ) return 0; // test width 3508 if ( get16(s) < 1 ) return 0; // test height 3509 sz = get8(s); // bits per pixel 3510 if ( (sz != 8) && (sz != 16) && (sz != 24) && (sz != 32) ) return 0; // only RGB or RGBA or grey allowed 3511 return 1; // seems to have passed everything 3512} 3513 3514#ifndef STBI_NO_STDIO 3515int stbi_tga_test_file (FILE *f) 3516{ 3517 stbi s; 3518 int r,n = ftell(f); 3519 start_file(&s, f); 3520 r = tga_test(&s); 3521 fseek(f,n,SEEK_SET); 3522 return r; 3523} 3524#endif 3525 3526int stbi_tga_test_memory (stbi_uc const *buffer, int len) 3527{ 3528 stbi s; 3529 start_mem(&s, buffer, len); 3530 return tga_test(&s); 3531} 3532 3533static stbi_uc *tga_load(stbi *s, int *x, int *y, int *comp, int req_comp) 3534{ 3535 // read in the TGA header stuff 3536 int tga_offset = get8u(s); 3537 int tga_indexed = get8u(s); 3538 int tga_image_type = get8u(s); 3539 int tga_is_RLE = 0; 3540 int tga_palette_start = get16le(s); 3541 int tga_palette_len = get16le(s); 3542 int tga_palette_bits = get8u(s); 3543 int tga_x_origin = get16le(s); 3544 int tga_y_origin = get16le(s); 3545 int tga_width = get16le(s); 3546 int tga_height = get16le(s); 3547 int tga_bits_per_pixel = get8u(s); 3548 int tga_inverted = get8u(s); 3549 // image data 3550 unsigned char *tga_data; 3551 unsigned char *tga_palette = NULL; 3552 int i, j; 3553 unsigned char raw_data[4]; 3554 unsigned char trans_data[4]; 3555 int RLE_count = 0; 3556 int RLE_repeating = 0; 3557 int read_next_pixel = 1; 3558 3559 // do a tiny bit of precessing 3560 if ( tga_image_type >= 8 ) 3561 { 3562 tga_image_type -= 8; 3563 tga_is_RLE = 1; 3564 } 3565 /* int tga_alpha_bits = tga_inverted & 15; */ 3566 tga_inverted = 1 - ((tga_inverted >> 5) & 1); 3567 3568 // error check 3569 if ( //(tga_indexed) || 3570 (tga_width < 1) || (tga_height < 1) || 3571 (tga_image_type < 1) || (tga_image_type > 3) || 3572 ((tga_bits_per_pixel != 8) && (tga_bits_per_pixel != 16) && 3573 (tga_bits_per_pixel != 24) && (tga_bits_per_pixel != 32)) 3574 ) 3575 { 3576 return NULL; 3577 } 3578 3579 // If I'm paletted, then I'll use the number of bits from the palette 3580 if ( tga_indexed ) 3581 { 3582 tga_bits_per_pixel = tga_palette_bits; 3583 } 3584 3585 // tga info 3586 *x = tga_width; 3587 *y = tga_height; 3588 if ( (req_comp < 1) || (req_comp > 4) ) 3589 { 3590 // just use whatever the file was 3591 req_comp = tga_bits_per_pixel / 8; 3592 *comp = req_comp; 3593 } else 3594 { 3595 // force a new number of components 3596 *comp = tga_bits_per_pixel/8; 3597 } 3598 tga_data = (unsigned char*)MALLOC( tga_width * tga_height * req_comp ); 3599 3600 // skip to the data's starting position (offset usually = 0) 3601 skip(s, tga_offset ); 3602 // do I need to load a palette? 3603 if ( tga_indexed ) 3604 { 3605 // any data to skip? (offset usually = 0) 3606 skip(s, tga_palette_start ); 3607 // load the palette 3608 tga_palette = (unsigned char*)MALLOC( tga_palette_len * tga_palette_bits / 8 ); 3609 if (!getn(s, tga_palette, tga_palette_len * tga_palette_bits / 8 )) 3610 return NULL; 3611 } 3612 // load the data 3613 trans_data[0] = trans_data[1] = trans_data[2] = trans_data[3] = 0; 3614 for (i=0; i < tga_width * tga_height; ++i) 3615 { 3616 // if I'm in RLE mode, do I need to get a RLE chunk? 3617 if ( tga_is_RLE ) 3618 { 3619 if ( RLE_count == 0 ) 3620 { 3621 // yep, get the next byte as a RLE command 3622 int RLE_cmd = get8u(s); 3623 RLE_count = 1 + (RLE_cmd & 127); 3624 RLE_repeating = RLE_cmd >> 7; 3625 read_next_pixel = 1; 3626 } else if ( !RLE_repeating ) 3627 { 3628 read_next_pixel = 1; 3629 } 3630 } else 3631 { 3632 read_next_pixel = 1; 3633 } 3634 // OK, if I need to read a pixel, do it now 3635 if ( read_next_pixel ) 3636 { 3637 // load however much data we did have 3638 if ( tga_indexed ) 3639 { 3640 // read in 1 byte, then perform the lookup 3641 int pal_idx = get8u(s); 3642 if ( pal_idx >= tga_palette_len ) 3643 { 3644 // invalid index 3645 pal_idx = 0; 3646 } 3647 pal_idx *= tga_bits_per_pixel / 8; 3648 for (j = 0; j*8 < tga_bits_per_pixel; ++j) 3649 { 3650 raw_data[j] = tga_palette[pal_idx+j]; 3651 } 3652 } else 3653 { 3654 // read in the data raw 3655 for (j = 0; j*8 < tga_bits_per_pixel; ++j) 3656 { 3657 raw_data[j] = get8u(s); 3658 } 3659 } 3660 // convert raw to the intermediate format 3661 switch (tga_bits_per_pixel) 3662 { 3663 case 8: 3664 // Luminous => RGBA 3665 trans_data[0] = raw_data[0]; 3666 trans_data[1] = raw_data[0]; 3667 trans_data[2] = raw_data[0]; 3668 trans_data[3] = 255; 3669 break; 3670 case 16: 3671 // Luminous,Alpha => RGBA 3672 trans_data[0] = raw_data[0]; 3673 trans_data[1] = raw_data[0]; 3674 trans_data[2] = raw_data[0]; 3675 trans_data[3] = raw_data[1]; 3676 break; 3677 case 24: 3678 // BGR => RGBA 3679 trans_data[0] = raw_data[2]; 3680 trans_data[1] = raw_data[1]; 3681 trans_data[2] = raw_data[0]; 3682 trans_data[3] = 255; 3683 break; 3684 case 32: 3685 // BGRA => RGBA 3686 trans_data[0] = raw_data[2]; 3687 trans_data[1] = raw_data[1]; 3688 trans_data[2] = raw_data[0]; 3689 trans_data[3] = raw_data[3]; 3690 break; 3691 } 3692 // clear the reading flag for the next pixel 3693 read_next_pixel = 0; 3694 } // end of reading a pixel 3695 // convert to final format 3696 switch (req_comp) 3697 { 3698 case 1: 3699 // RGBA => Luminance 3700 tga_data[i*req_comp+0] = compute_y(trans_data[0],trans_data[1],trans_data[2]); 3701 break; 3702 case 2: 3703 // RGBA => Luminance,Alpha 3704 tga_data[i*req_comp+0] = compute_y(trans_data[0],trans_data[1],trans_data[2]); 3705 tga_data[i*req_comp+1] = trans_data[3]; 3706 break; 3707 case 3: 3708 // RGBA => RGB 3709 tga_data[i*req_comp+0] = trans_data[0]; 3710 tga_data[i*req_comp+1] = trans_data[1]; 3711 tga_data[i*req_comp+2] = trans_data[2]; 3712 break; 3713 case 4: 3714 // RGBA => RGBA 3715 tga_data[i*req_comp+0] = trans_data[0]; 3716 tga_data[i*req_comp+1] = trans_data[1]; 3717 tga_data[i*req_comp+2] = trans_data[2]; 3718 tga_data[i*req_comp+3] = trans_data[3]; 3719 break; 3720 } 3721 // in case we're in RLE mode, keep counting down 3722 --RLE_count; 3723 } 3724 // do I need to invert the image? 3725 if ( tga_inverted ) 3726 { 3727 for (j = 0; j*2 < tga_height; ++j) 3728 { 3729 int index1 = j * tga_width * req_comp; 3730 int index2 = (tga_height - 1 - j) * tga_width * req_comp; 3731 for (i = tga_width * req_comp; i > 0; --i) 3732 { 3733 unsigned char temp = tga_data[index1]; 3734 tga_data[index1] = tga_data[index2]; 3735 tga_data[index2] = temp; 3736 ++index1; 3737 ++index2; 3738 } 3739 } 3740 } 3741 // clear my palette, if I had one 3742 if ( tga_palette != NULL ) 3743 { 3744 FREE( tga_palette ); 3745 } 3746 // the things I do to get rid of an error message, and yet keep 3747 // Microsoft's C compilers happy... [8^( 3748 tga_palette_start = tga_palette_len = tga_palette_bits = 3749 tga_x_origin = tga_y_origin = 0; 3750 // OK, done 3751 return tga_data; 3752} 3753 3754#ifndef STBI_NO_STDIO 3755stbi_uc *stbi_tga_load (char const *filename, int *x, int *y, int *comp, int req_comp) 3756{ 3757 stbi_uc *data; 3758 FILE *f = fopen(filename, "rb"); 3759 if (!f) return NULL; 3760 data = stbi_tga_load_from_file(f, x,y,comp,req_comp); 3761 fclose(f); 3762 return data; 3763} 3764 3765stbi_uc *stbi_tga_load_from_file (FILE *f, int *x, int *y, int *comp, int req_comp) 3766{ 3767 stbi s; 3768 start_file(&s, f); 3769 return tga_load(&s, x,y,comp,req_comp); 3770} 3771#endif 3772 3773stbi_uc *stbi_tga_load_from_memory (stbi_uc const *buffer, int len, int *x, int *y, int *comp, int req_comp) 3774{ 3775 stbi s; 3776 start_mem(&s, buffer, len); 3777 return tga_load(&s, x,y,comp,req_comp); 3778} 3779 3780 3781// ************************************************************************************************* 3782// Photoshop PSD loader -- PD by Thatcher Ulrich, integration by Nicolas Schulz, tweaked by STB 3783 3784static int psd_test(stbi *s) 3785{ 3786 if (get32(s) != 0x38425053) return 0; // "8BPS" 3787 else return 1; 3788} 3789 3790#ifndef STBI_NO_STDIO 3791int stbi_psd_test_file(FILE *f) 3792{ 3793 stbi s; 3794 int r,n = ftell(f); 3795 start_file(&s, f); 3796 r = psd_test(&s); 3797 fseek(f,n,SEEK_SET); 3798 return r; 3799} 3800#endif 3801 3802int stbi_psd_test_memory(stbi_uc const *buffer, int len) 3803{ 3804 stbi s; 3805 start_mem(&s, buffer, len); 3806 return psd_test(&s); 3807} 3808 3809static stbi_uc *psd_load(stbi *s, int *x, int *y, int *comp, int req_comp) 3810{ 3811 int pixelCount; 3812 int channelCount, compression; 3813 int channel, i, count, len; 3814 int w,h; 3815 uint8 *out; 3816 3817 // Check identifier 3818 if (get32(s) != 0x38425053) // "8BPS" 3819 return epuc("not PSD", "Corrupt PSD image"); 3820 3821 // Check file type version. 3822 if (get16(s) != 1) 3823 return epuc("wrong version", "Unsupported version of PSD image"); 3824 3825 // Skip 6 reserved bytes. 3826 skip(s, 6 ); 3827 3828 // Read the number of channels (R, G, B, A, etc). 3829 channelCount = get16(s); 3830 if (channelCount < 0 || channelCount > 16) 3831 return epuc("wrong channel count", "Unsupported number of channels in PSD image"); 3832 3833 // Read the rows and columns of the image. 3834 h = get32(s); 3835 w = get32(s); 3836 3837 // Make sure the depth is 8 bits. 3838 if (get16(s) != 8) 3839 return epuc("unsupported bit depth", "PSD bit depth is not 8 bit"); 3840 3841 // Make sure the color mode is RGB. 3842 // Valid options are: 3843 // 0: Bitmap 3844 // 1: Grayscale 3845 // 2: Indexed color 3846 // 3: RGB color 3847 // 4: CMYK color 3848 // 7: Multichannel 3849 // 8: Duotone 3850 // 9: Lab color 3851 if (get16(s) != 3) 3852 return epuc("wrong color format", "PSD is not in RGB color format"); 3853 3854 // Skip the Mode Data. (It's the palette for indexed color; other info for other modes.) 3855 skip(s,get32(s) ); 3856 3857 // Skip the image resources. (resolution, pen tool paths, etc) 3858 skip(s, get32(s) ); 3859 3860 // Skip the reserved data. 3861 skip(s, get32(s) ); 3862 3863 // Find out if the data is compressed. 3864 // Known values: 3865 // 0: no compression 3866 // 1: RLE compressed 3867 compression = get16(s); 3868 if (compression > 1) 3869 return epuc("bad compression", "PSD has an unknown compression format"); 3870 3871 // Create the destination image. 3872 out = (stbi_uc *) MALLOC(4 * w*h); 3873 if (!out) return epuc("outofmem", "Out of memory"); 3874 pixelCount = w*h; 3875 3876 // Initialize the data to zero. 3877 //memset( out, 0, pixelCount * 4 ); 3878 3879 // Finally, the image data. 3880 if (compression) { 3881 // RLE as used by .PSD and .TIFF 3882 // Loop until you get the number of unpacked bytes you are expecting: 3883 // Read the next source byte into n. 3884 // If n is between 0 and 127 inclusive, copy the next n+1 bytes literally. 3885 // Else if n is between -127 and -1 inclusive, copy the next byte -n+1 times. 3886 // Else if n is 128, noop. 3887 // Endloop 3888 3889 // The RLE-compressed data is preceeded by a 2-byte data count for each row in the data, 3890 // which we're going to just skip. 3891 skip(s, h * channelCount * 2 ); 3892 3893 // Read the RLE data by channel. 3894 for (channel = 0; channel < 4; channel++) { 3895 uint8 *p; 3896 3897 p = out+channel; 3898 if (channel >= channelCount) { 3899 // Fill this channel with default data. 3900 for (i = 0; i < pixelCount; i++) *p = (channel == 3 ? 255 : 0), p += 4; 3901 } else { 3902 // Read the RLE data. 3903 count = 0; 3904 while (count < pixelCount) { 3905 len = get8(s); 3906 if (len == 128) { 3907 // No-op. 3908 } else if (len < 128) { 3909 // Copy next len+1 bytes literally. 3910 len++; 3911 count += len; 3912 while (len) { 3913 *p = get8u(s); 3914 p += 4; 3915 len--; 3916 } 3917 } else if (len > 128) { 3918 uint8 val; 3919 // Next -len+1 bytes in the dest are replicated from next source byte. 3920 // (Interpret len as a negative 8-bit int.) 3921 len ^= 0x0FF; 3922 len += 2; 3923 val = get8u(s); 3924 count += len; 3925 while (len) { 3926 *p = val; 3927 p += 4; 3928 len--; 3929 } 3930 } 3931 } 3932 } 3933 } 3934 3935 } else { 3936 // We're at the raw image data. It's each channel in order (Red, Green, Blue, Alpha, ...) 3937 // where each channel consists of an 8-bit value for each pixel in the image. 3938 3939 // Read the data by channel. 3940 for (channel = 0; channel < 4; channel++) { 3941 uint8 *p; 3942 3943 p = out + channel; 3944 if (channel > channelCount) { 3945 // Fill this channel with default data. 3946 for (i = 0; i < pixelCount; i++) *p = channel == 3 ? 255 : 0, p += 4; 3947 } else { 3948 // Read the data. 3949 for (i = 0; i < pixelCount; i++) 3950 *p = get8u(s), p += 4; 3951 } 3952 } 3953 } 3954 3955 if (req_comp && req_comp != 4) { 3956 out = convert_format(out, 4, req_comp, w, h); 3957 if (out == NULL) return out; // convert_format frees input on failure 3958 } 3959 3960 if (comp) *comp = channelCount; 3961 *y = h; 3962 *x = w; 3963 3964 return out; 3965} 3966 3967#ifndef STBI_NO_STDIO 3968stbi_uc *stbi_psd_load(char const *filename, int *x, int *y, int *comp, int req_comp) 3969{ 3970 stbi_uc *data; 3971 FILE *f = fopen(filename, "rb"); 3972 if (!f) return NULL; 3973 data = stbi_psd_load_from_file(f, x,y,comp,req_comp); 3974 fclose(f); 3975 return data; 3976} 3977 3978stbi_uc *stbi_psd_load_from_file(FILE *f, int *x, int *y, int *comp, int req_comp) 3979{ 3980 stbi s; 3981 start_file(&s, f); 3982 return psd_load(&s, x,y,comp,req_comp); 3983} 3984#endif 3985 3986stbi_uc *stbi_psd_load_from_memory (stbi_uc const *buffer, int len, int *x, int *y, int *comp, int req_comp) 3987{ 3988 stbi s; 3989 start_mem(&s, buffer, len); 3990 return psd_load(&s, x,y,comp,req_comp); 3991} 3992 3993// ************************************************************************************************* 3994// Softimage PIC loader 3995// by Tom Seddon 3996// 3997// See http://softimage.wiki.softimage.com/index.php/INFO:_PIC_file_format 3998// See http://ozviz.wasp.uwa.edu.au/~pbourke/dataformats/softimagepic/ 3999 4000static int pic_is4(stbi *s,const char *str) 4001{ 4002 int i; 4003 for (i=0; i<4; ++i) 4004 if (get8(s) != (stbi_uc)str[i]) 4005 return 0; 4006 4007 return 1; 4008} 4009 4010static int pic_test(stbi *s) 4011{ 4012 int i; 4013 4014 if (!pic_is4(s,"\x53\x80\xF6\x34")) 4015 return 0; 4016 4017 for(i=0;i<84;++i) 4018 get8(s); 4019 4020 if (!pic_is4(s,"PICT")) 4021 return 0; 4022 4023 return 1; 4024} 4025 4026typedef struct 4027{ 4028 stbi_uc size,type,channel; 4029} pic_packet_t; 4030 4031static stbi_uc *pic_readval(stbi *s, int channel, stbi_uc *dest) 4032{ 4033 int mask=0x80, i; 4034 4035 for (i=0; i<4; ++i, mask>>=1) { 4036 if (channel & mask) { 4037 if (at_eof(s)) return epuc("bad file","PIC file too short"); 4038 dest[i]=get8u(s); 4039 } 4040 } 4041 4042 return dest; 4043} 4044 4045static void pic_copyval(int channel,stbi_uc *dest,const stbi_uc *src) 4046{ 4047 int mask=0x80,i; 4048 4049 for (i=0;i<4; ++i, mask>>=1) 4050 if (channel&mask) 4051 dest[i]=src[i]; 4052} 4053 4054static stbi_uc *pic_load2(stbi *s,int width,int height,int *comp, stbi_uc *result) 4055{ 4056 int act_comp=0,num_packets=0,y,chained; 4057 pic_packet_t packets[10]; 4058 4059 // this will (should...) cater for even some bizarre stuff like having data 4060 // for the same channel in multiple packets. 4061 do { 4062 pic_packet_t *packet; 4063 4064 if (num_packets==sizeof(packets)/sizeof(packets[0])) 4065 return epuc("bad format","too many packets"); 4066 4067 packet = &packets[num_packets++]; 4068 4069 chained = get8(s); 4070 packet->size = get8u(s); 4071 packet->type = get8u(s); 4072 packet->channel = get8u(s); 4073 4074 act_comp |= packet->channel; 4075 4076 if (at_eof(s)) return epuc("bad file","file too short (reading packets)"); 4077 if (packet->size != 8) return epuc("bad format","packet isn't 8bpp"); 4078 } while (chained); 4079 4080 *comp = (act_comp & 0x10 ? 4 : 3); // has alpha channel? 4081 4082 for(y=0; y<height; ++y) { 4083 int packet_idx; 4084 4085 for(packet_idx=0; packet_idx < num_packets; ++packet_idx) { 4086 pic_packet_t *packet = &packets[packet_idx]; 4087 stbi_uc *dest = result+y*width*4; 4088 4089 switch (packet->type) { 4090 default: 4091 return epuc("bad format","packet has bad compression type"); 4092 4093 case 0: {//uncompressed 4094 int x; 4095 4096 for(x=0;x<width;++x, dest+=4) 4097 if (!pic_readval(s,packet->channel,dest)) 4098 return 0; 4099 break; 4100 } 4101 4102 case 1://Pure RLE 4103 { 4104 int left=width, i; 4105 4106 while (left>0) { 4107 stbi_uc count,value[4]; 4108 4109 count=get8u(s); 4110 if (at_eof(s)) return epuc("bad file","file too short (pure read count)"); 4111 4112 if (count > left) 4113 count = (uint8) left; 4114 4115 if (!pic_readval(s,packet->channel,value)) return 0; 4116 4117 for(i=0; i<count; ++i,dest+=4) 4118 pic_copyval(packet->channel,dest,value); 4119 left -= count; 4120 } 4121 } 4122 break; 4123 4124 case 2: {//Mixed RLE 4125 int left=width; 4126 while (left>0) { 4127 int count = get8(s), i; 4128 if (at_eof(s)) return epuc("bad file","file too short (mixed read count)"); 4129 4130 if (count >= 128) { // Repeated 4131 stbi_uc value[4]; 4132 4133 if (count==128) 4134 count = get16(s); 4135 else 4136 count -= 127; 4137 if (count > left) 4138 return epuc("bad file","scanline overrun"); 4139 4140 if (!pic_readval(s,packet->channel,value)) 4141 return 0; 4142 4143 for(i=0;i<count;++i, dest += 4) 4144 pic_copyval(packet->channel,dest,value); 4145 } else { // Raw 4146 ++count; 4147 if (count>left) return epuc("bad file","scanline overrun"); 4148 4149 for(i=0;i<count;++i, dest+=4) 4150 if (!pic_readval(s,packet->channel,dest)) 4151 return 0; 4152 } 4153 left-=count; 4154 } 4155 break; 4156 } 4157 } 4158 } 4159 } 4160 4161 return result; 4162} 4163 4164static stbi_uc *pic_load(stbi *s,int *px,int *py,int *comp,int req_comp) 4165{ 4166 stbi_uc *result; 4167 int i, x,y; 4168 4169 for (i=0; i<92; ++i) 4170 get8(s); 4171 4172 x = get16(s); 4173 y = get16(s); 4174 if (at_eof(s)) return epuc("bad file","file too short (pic header)"); 4175 if ((1 << 28) / x < y) return epuc("too large", "Image too large to decode"); 4176 4177 get32(s); //skip `ratio' 4178 get16(s); //skip `fields' 4179 get16(s); //skip `pad' 4180 4181 // intermediate buffer is RGBA 4182 result = (stbi_uc *) MALLOC(x*y*4); 4183 memset(result, 0xff, x*y*4); 4184 4185 if (!pic_load2(s,x,y,comp, result)) { 4186 FREE(result); 4187 result=0; 4188 } 4189 *px = x; 4190 *py = y; 4191 if (req_comp == 0) req_comp = *comp; 4192 result=convert_format(result,4,req_comp,x,y); 4193 4194 return result; 4195} 4196 4197int stbi_pic_test_memory(stbi_uc const *buffer, int len) 4198{ 4199 stbi s; 4200 start_mem(&s,buffer,len); 4201 return pic_test(&s); 4202} 4203 4204stbi_uc *stbi_pic_load_from_memory (stbi_uc const *buffer, int len, int *x, int *y, int *comp, int req_comp) 4205{ 4206 stbi s; 4207 start_mem(&s,buffer,len); 4208 return pic_load(&s,x,y,comp,req_comp); 4209} 4210 4211#ifndef STBI_NO_STDIO 4212int stbi_pic_test_file(FILE *f) 4213{ 4214 int result; 4215 long l = ftell(f); 4216 stbi s; 4217 start_file(&s,f); 4218 result = pic_test(&s); 4219 fseek(f,l,SEEK_SET); 4220 return result; 4221} 4222 4223stbi_uc *stbi_pic_load(char const *filename,int *x, int *y, int *comp, int req_comp) 4224{ 4225 stbi_uc *result; 4226 FILE *f=fopen(filename,"rb"); 4227 if (!f) return 0; 4228 result = stbi_pic_load_from_file(f,x,y,comp,req_comp); 4229 fclose(f); 4230 return result; 4231} 4232 4233stbi_uc *stbi_pic_load_from_file(FILE *f,int *x, int *y, int *comp, int req_comp) 4234{ 4235 stbi s; 4236 start_file(&s,f); 4237 return pic_load(&s,x,y,comp,req_comp); 4238} 4239#endif 4240 4241// ************************************************************************************************* 4242// GIF loader -- public domain by Jean-Marc Lienher -- simplified/shrunk by stb 4243typedef struct stbi_gif_lzw_struct { 4244 int16 prefix; 4245 uint8 first; 4246 uint8 suffix; 4247} stbi_gif_lzw; 4248 4249typedef struct stbi_gif_struct 4250{ 4251 int w,h; 4252 stbi_uc *out; // output buffer (always 4 components) 4253 int flags, bgindex, ratio, transparent, eflags; 4254 uint8 pal[256][4]; 4255 uint8 lpal[256][4]; 4256 stbi_gif_lzw codes[4096]; 4257 uint8 *color_table; 4258 int parse, step; 4259 int lflags; 4260 int start_x, start_y; 4261 int max_x, max_y; 4262 int cur_x, cur_y; 4263 int line_size; 4264} stbi_gif; 4265 4266static int gif_test(stbi *s) 4267{ 4268 int sz; 4269 if (get8(s) != 'G' || get8(s) != 'I' || get8(s) != 'F' || get8(s) != '8') return 0; 4270 sz = get8(s); 4271 if (sz != '9' && sz != '7') return 0; 4272 if (get8(s) != 'a') return 0; 4273 return 1; 4274} 4275 4276#ifndef STBI_NO_STDIO 4277int stbi_gif_test_file (FILE *f) 4278{ 4279 stbi s; 4280 int r,n = ftell(f); 4281 start_file(&s,f); 4282 r = gif_test(&s); 4283 fseek(f,n,SEEK_SET); 4284 return r; 4285} 4286#endif 4287 4288int stbi_gif_test_memory (stbi_uc const *buffer, int len) 4289{ 4290 stbi s; 4291 start_mem(&s, buffer, len); 4292 return gif_test(&s); 4293} 4294 4295static void stbi_gif_parse_colortable(stbi *s, uint8 pal[256][4], int num_entries, int transp) 4296{ 4297 int i; 4298 for (i=0; i < num_entries; ++i) { 4299 pal[i][2] = get8u(s); 4300 pal[i][1] = get8u(s); 4301 pal[i][0] = get8u(s); 4302 pal[i][3] = transp ? 0 : 255; 4303 } 4304} 4305 4306static int stbi_gif_header(stbi *s, stbi_gif *g, int *comp, int is_info) 4307{ 4308 uint8 ver; 4309 if (get8(s) != 'G' || get8(s) != 'I' || get8(s) != 'F' || get8(s) != '8') 4310 return e("not GIF", "Corrupt GIF"); 4311 4312 ver = get8u(s); 4313 if (ver != '7' && ver != '9') return e("not GIF", "Corrupt GIF"); 4314 if (get8(s) != 'a') return e("not GIF", "Corrupt GIF"); 4315 4316 failure_reason = ""; 4317 g->w = get16le(s); 4318 g->h = get16le(s); 4319 g->flags = get8(s); 4320 g->bgindex = get8(s); 4321 g->ratio = get8(s); 4322 g->transparent = -1; 4323 4324 if (comp != 0) *comp = 4; // can't actually tell whether it's 3 or 4 until we parse the comments 4325 4326 if (is_info) return 1; 4327 4328 if (g->flags & 0x80) 4329 stbi_gif_parse_colortable(s,g->pal, 2 << (g->flags & 7), -1); 4330 4331 return 1; 4332} 4333 4334static int stbi_gif_info_raw(stbi *s, int *x, int *y, int *comp) 4335{ 4336 stbi_gif g; 4337 if (!stbi_gif_header(s, &g, comp, 1)) return 0; 4338 if (x) *x = g.w; 4339 if (y) *y = g.h; 4340 return 1; 4341} 4342 4343static void stbi_out_gif_code(stbi_gif *g, uint16 code) 4344{ 4345 uint8 *p, *c; 4346 4347 // recurse to decode the prefixes, since the linked-list is backwards, 4348 // and working backwards through an interleaved image would be nasty 4349 if (g->codes[code].prefix >= 0) 4350 stbi_out_gif_code(g, g->codes[code].prefix); 4351 4352 if (g->cur_y >= g->max_y) return; 4353 4354 p = &g->out[g->cur_x + g->cur_y]; 4355 c = &g->color_table[g->codes[code].suffix * 4]; 4356 4357 if (c[3] >= 128) { 4358 p[0] = c[2]; 4359 p[1] = c[1]; 4360 p[2] = c[0]; 4361 p[3] = c[3]; 4362 } 4363 g->cur_x += 4; 4364 4365 if (g->cur_x >= g->max_x) { 4366 g->cur_x = g->start_x; 4367 g->cur_y += g->step; 4368 4369 while (g->cur_y >= g->max_y && g->parse > 0) { 4370 g->step = (1 << g->parse) * g->line_size; 4371 g->cur_y = g->start_y + (g->step >> 1); 4372 --g->parse; 4373 } 4374 } 4375} 4376 4377static uint8 *stbi_process_gif_raster(stbi *s, stbi_gif *g) 4378{ 4379 uint8 lzw_cs; 4380 int32 len, code; 4381 uint32 first; 4382 int32 codesize, codemask, avail, oldcode, bits, valid_bits, clear; 4383 stbi_gif_lzw *p; 4384 4385 lzw_cs = get8u(s); 4386 clear = 1 << lzw_cs; 4387 first = 1; 4388 codesize = lzw_cs + 1; 4389 codemask = (1 << codesize) - 1; 4390 bits = 0; 4391 valid_bits = 0; 4392 for (code = 0; code < clear; code++) { 4393 g->codes[code].prefix = -1; 4394 g->codes[code].first = (uint8) code; 4395 g->codes[code].suffix = (uint8) code; 4396 } 4397 4398 // support no starting clear code 4399 avail = clear+2; 4400 oldcode = -1; 4401 4402 len = 0; 4403 for(;;) { 4404 if (valid_bits < codesize) { 4405 if (len == 0) { 4406 len = get8(s); // start new block 4407 if (len == 0) 4408 return g->out; 4409 } 4410 --len; 4411 bits |= (int32) get8(s) << valid_bits; 4412 valid_bits += 8; 4413 } else { 4414 code = bits & codemask; 4415 bits >>= codesize; 4416 valid_bits -= codesize; 4417 // @OPTIMIZE: is there some way we can accelerate the non-clear path? 4418 if (code == clear) { // clear code 4419 codesize = lzw_cs + 1; 4420 codemask = (1 << codesize) - 1; 4421 avail = clear + 2; 4422 oldcode = -1; 4423 first = 0; 4424 } else if (code == clear + 1) { // end of stream code 4425 skip(s, len); 4426 while ((len = get8(s)) > 0) 4427 skip(s,len); 4428 return g->out; 4429 } else if (code <= avail) { 4430 if (first) return epuc("no clear code", "Corrupt GIF"); 4431 4432 if (oldcode >= 0) { 4433 p = &g->codes[avail++]; 4434 if (avail > 4096) return epuc("too many codes", "Corrupt GIF"); 4435 p->prefix = (int16) oldcode; 4436 p->first = g->codes[oldcode].first; 4437 p->suffix = (code == avail) ? p->first : g->codes[code].first; 4438 } else if (code == avail) 4439 return epuc("illegal code in raster", "Corrupt GIF"); 4440 4441 stbi_out_gif_code(g, (uint16) code); 4442 4443 if ((avail & codemask) == 0 && avail <= 0x0FFF) { 4444 codesize++; 4445 codemask = (1 << codesize) - 1; 4446 } 4447 4448 oldcode = code; 4449 } else { 4450 return epuc("illegal code in raster", "Corrupt GIF"); 4451 } 4452 } 4453 } 4454} 4455 4456static void stbi_fill_gif_background(stbi_gif *g) 4457{ 4458 int i; 4459 uint8 *c = g->pal[g->bgindex]; 4460 // @OPTIMIZE: write a dword at a time 4461 for (i = 0; i < g->w * g->h * 4; i += 4) { 4462 uint8 *p = &g->out[i]; 4463 p[0] = c[2]; 4464 p[1] = c[1]; 4465 p[2] = c[0]; 4466 p[3] = c[3]; 4467 } 4468} 4469 4470// this function is designed to support animated gifs, although stb_image doesn't support it 4471static uint8 *stbi_gif_load_next(stbi *s, stbi_gif *g, int *comp, int req_comp) 4472{ 4473 int i; 4474 uint8 *old_out = 0; 4475 4476 if (g->out == 0) { 4477 if (!stbi_gif_header(s, g, comp,0)) return 0; // failure_reason set by stbi_gif_header 4478 g->out = (uint8 *) MALLOC(4 * g->w * g->h); 4479 if (g->out == 0) return epuc("outofmem", "Out of memory"); 4480 stbi_fill_gif_background(g); 4481 } else { 4482 // animated-gif-only path 4483 if (((g->eflags & 0x1C) >> 2) == 3) { 4484 old_out = g->out; 4485 g->out = (uint8 *) MALLOC(4 * g->w * g->h); 4486 if (g->out == 0) return epuc("outofmem", "Out of memory"); 4487 memcpy(g->out, old_out, g->w*g->h*4); 4488 } 4489 } 4490 4491 for (;;) { 4492 switch (get8(s)) { 4493 case 0x2C: /* Image Descriptor */ 4494 { 4495 int32 x, y, w, h; 4496 uint8 *o; 4497 4498 x = get16le(s); 4499 y = get16le(s); 4500 w = get16le(s); 4501 h = get16le(s); 4502 if (((x + w) > (g->w)) || ((y + h) > (g->h))) 4503 return epuc("bad Image Descriptor", "Corrupt GIF"); 4504 4505 g->line_size = g->w * 4; 4506 g->start_x = x * 4; 4507 g->start_y = y * g->line_size; 4508 g->max_x = g->start_x + w * 4; 4509 g->max_y = g->start_y + h * g->line_size; 4510 g->cur_x = g->start_x; 4511 g->cur_y = g->start_y; 4512 4513 g->lflags = get8(s); 4514 4515 if (g->lflags & 0x40) { 4516 g->step = 8 * g->line_size; // first interlaced spacing 4517 g->parse = 3; 4518 } else { 4519 g->step = g->line_size; 4520 g->parse = 0; 4521 } 4522 4523 if (g->lflags & 0x80) { 4524 stbi_gif_parse_colortable(s,g->lpal, 2 << (g->lflags & 7), g->eflags & 0x01 ? g->transparent : -1); 4525 g->color_table = (uint8 *) g->lpal; 4526 } else if (g->flags & 0x80) { 4527 for (i=0; i < 256; ++i) // @OPTIMIZE: reset only the previous transparent 4528 g->pal[i][3] = 255; 4529 if (g->transparent >= 0 && (g->eflags & 0x01)) 4530 g->pal[g->transparent][3] = 0; 4531 g->color_table = (uint8 *) g->pal; 4532 } else 4533 return epuc("missing color table", "Corrupt GIF"); 4534 4535 o = stbi_process_gif_raster(s, g); 4536 if (o == NULL) return NULL; 4537 4538 if (req_comp && req_comp != 4) 4539 o = convert_format(o, 4, req_comp, g->w, g->h); 4540 return o; 4541 } 4542 4543 case 0x21: // Comment Extension. 4544 { 4545 int len; 4546 if (get8(s) == 0xF9) { // Graphic Control Extension. 4547 len = get8(s); 4548 if (len == 4) { 4549 g->eflags = get8(s); 4550 get16le(s); // delay 4551 g->transparent = get8(s); 4552 } else { 4553 skip(s, len); 4554 break; 4555 } 4556 } 4557 while ((len = get8(s)) != 0) 4558 skip(s, len); 4559 break; 4560 } 4561 4562 case 0x3B: // gif stream termination code 4563 return (uint8 *) 1; 4564 4565 default: 4566 return epuc("unknown code", "Corrupt GIF"); 4567 } 4568 } 4569} 4570 4571#ifndef STBI_NO_STDIO 4572stbi_uc *stbi_gif_load (char const *filename, int *x, int *y, int *comp, int req_comp) 4573{ 4574 uint8 *data; 4575 FILE *f = fopen(filename, "rb"); 4576 if (!f) return NULL; 4577 data = stbi_gif_load_from_file(f, x,y,comp,req_comp); 4578 fclose(f); 4579 return data; 4580} 4581 4582stbi_uc *stbi_gif_load_from_file (FILE *f, int *x, int *y, int *comp, int req_comp) 4583{ 4584 uint8 *u = 0; 4585 stbi s; 4586 stbi_gif g={0}; 4587 start_file(&s, f); 4588 4589 u = stbi_gif_load_next(&s, &g, comp, req_comp); 4590 if (u == (void *) 1) u = 0; // end of animated gif marker 4591 if (u) { 4592 *x = g.w; 4593 *y = g.h; 4594 } 4595 4596 return u; 4597} 4598#endif 4599 4600stbi_uc *stbi_gif_load_from_memory (stbi_uc const *buffer, int len, int *x, int *y, int *comp, int req_comp) 4601{ 4602 uint8 *u = 0; 4603 stbi s; 4604 stbi_gif *pg; 4605 4606 #ifdef STBI_SMALL_STACK 4607 pg = (stbi_gif *) MALLOC(sizeof(*pg)); 4608 if (pg == NULL) 4609 return NULL; 4610 #else 4611 stbi_gif g; 4612 pg = &g; 4613 #endif 4614 4615 memset(pg, 0, sizeof(*pg)); 4616 start_mem(&s, buffer, len); 4617 u = stbi_gif_load_next(&s, pg, comp, req_comp); 4618 if (u == (void *) 1) u = 0; // end of animated gif marker 4619 if (u) { 4620 *x = pg->w; 4621 *y = pg->h; 4622 } 4623 4624 #ifdef STBI_SMALL_STACK 4625 FREE(pg); 4626 #endif 4627 4628 return u; 4629} 4630 4631#ifndef STBI_NO_STDIO 4632int stbi_gif_info (char const *filename, int *x, int *y, int *comp) 4633{ 4634 int res; 4635 FILE *f = fopen(filename, "rb"); 4636 if (!f) return 0; 4637 res = stbi_gif_info_from_file(f, x, y, comp); 4638 fclose(f); 4639 return res; 4640} 4641 4642int stbi_gif_info_from_file(FILE *f, int *x, int *y, int *comp) 4643{ 4644 stbi s; 4645 int res; 4646 long n = ftell(f); 4647 start_file(&s, f); 4648 res = stbi_gif_info_raw(&s, x, y, comp); 4649 fseek(f, n, SEEK_SET); 4650 return res; 4651} 4652#endif // !STBI_NO_STDIO 4653 4654int stbi_gif_info_from_memory(stbi_uc const *buffer, int len, int *x, int *y, int *comp) 4655{ 4656 stbi s; 4657 start_mem(&s, buffer, len); 4658 return stbi_gif_info_raw(&s, x, y, comp); 4659} 4660 4661 4662 4663 4664// ************************************************************************************************* 4665// Radiance RGBE HDR loader 4666// originally by Nicolas Schulz 4667#ifndef STBI_NO_HDR 4668static int hdr_test(stbi *s) 4669{ 4670 const char *signature = "#?RADIANCE\n"; 4671 int i; 4672 for (i=0; signature[i]; ++i) 4673 if (get8(s) != signature[i]) 4674 return 0; 4675 return 1; 4676} 4677 4678int stbi_hdr_test_memory(stbi_uc const *buffer, int len) 4679{ 4680 stbi s; 4681 start_mem(&s, buffer, len); 4682 return hdr_test(&s); 4683} 4684 4685#ifndef STBI_NO_STDIO 4686int stbi_hdr_test_file(FILE *f) 4687{ 4688 stbi s; 4689 int r,n = ftell(f); 4690 start_file(&s, f); 4691 r = hdr_test(&s); 4692 fseek(f,n,SEEK_SET); 4693 return r; 4694} 4695#endif 4696 4697#define HDR_BUFLEN 1024 4698static char *hdr_gettoken(stbi *z, char *buffer) 4699{ 4700 int len=0; 4701 char c = '\0'; 4702 4703 c = (char) get8(z); 4704 4705 while (!at_eof(z) && c != '\n') { 4706 buffer[len++] = c; 4707 if (len == HDR_BUFLEN-1) { 4708 // flush to end of line 4709 while (!at_eof(z) && get8(z) != '\n') 4710 ; 4711 break; 4712 } 4713 c = (char) get8(z); 4714 } 4715 4716 buffer[len] = 0; 4717 return buffer; 4718} 4719 4720static void hdr_convert(float *output, stbi_uc *input, int req_comp) 4721{ 4722 if ( input[3] != 0 ) { 4723 float f1; 4724 // Exponent 4725 f1 = (float) ldexp(1.0f, input[3] - (int)(128 + 8)); 4726 if (req_comp <= 2) 4727 output[0] = (input[0] + input[1] + input[2]) * f1 / 3; 4728 else { 4729 output[0] = input[0] * f1; 4730 output[1] = input[1] * f1; 4731 output[2] = input[2] * f1; 4732 } 4733 if (req_comp == 2) output[1] = 1; 4734 if (req_comp == 4) output[3] = 1; 4735 } else { 4736 switch (req_comp) { 4737 case 4: output[3] = 1; /* fallthrough */ 4738 case 3: output[0] = output[1] = output[2] = 0; 4739 break; 4740 case 2: output[1] = 1; /* fallthrough */ 4741 case 1: output[0] = 0; 4742 break; 4743 } 4744 } 4745} 4746 4747 4748static float *hdr_load(stbi *s, int *x, int *y, int *comp, int req_comp) 4749{ 4750 char buffer[HDR_BUFLEN]; 4751 char *token; 4752 int valid = 0; 4753 int width, height; 4754 stbi_uc *scanline; 4755 float *hdr_data; 4756 int len; 4757 unsigned char count, value; 4758 int i, j, k, c1,c2, z; 4759 4760 4761 // Check identifier 4762 if (strcmp(hdr_gettoken(s,buffer), "#?RADIANCE") != 0) 4763 return epf("not HDR", "Corrupt HDR image"); 4764 4765 // Parse header 4766 for(;;) { 4767 token = hdr_gettoken(s,buffer); 4768 if (token[0] == 0) break; 4769 if (strcmp(token, "FORMAT=32-bit_rle_rgbe") == 0) valid = 1; 4770 } 4771 4772 if (!valid) return epf("unsupported format", "Unsupported HDR format"); 4773 4774 // Parse width and height 4775 // can't use sscanf() if we're not using stdio! 4776 token = hdr_gettoken(s,buffer); 4777 if (strncmp(token, "-Y ", 3)) return epf("unsupported data layout", "Unsupported HDR format"); 4778 token += 3; 4779 height = strtol(token, &token, 10); 4780 while (*token == ' ') ++token; 4781 if (strncmp(token, "+X ", 3)) return epf("unsupported data layout", "Unsupported HDR format"); 4782 token += 3; 4783 width = strtol(token, NULL, 10); 4784 4785 *x = width; 4786 *y = height; 4787 4788 *comp = 3; 4789 if (req_comp == 0) req_comp = 3; 4790 4791 // Read data 4792 hdr_data = (float *) MALLOC(height * width * req_comp * sizeof(float)); 4793 4794 // Load image data 4795 // image data is stored as some number of sca 4796 if ( width < 8 || width >= 32768) { 4797 // Read flat data 4798 for (j=0; j < height; ++j) { 4799 for (i=0; i < width; ++i) { 4800 stbi_uc rgbe[4]; 4801 main_decode_loop: 4802 getn(s, rgbe, 4); 4803 hdr_convert(hdr_data + j * width * req_comp + i * req_comp, rgbe, req_comp); 4804 } 4805 } 4806 } else { 4807 // Read RLE-encoded data 4808 scanline = NULL; 4809 4810 for (j = 0; j < height; ++j) { 4811 c1 = get8(s); 4812 c2 = get8(s); 4813 len = get8(s); 4814 if (c1 != 2 || c2 != 2 || (len & 0x80)) { 4815 // not run-length encoded, so we have to actually use THIS data as a decoded 4816 // pixel (note this can't be a valid pixel--one of RGB must be >= 128) 4817 uint8 rgbe[4]; 4818 rgbe[0] = (uint8) c1; 4819 rgbe[1] = (uint8) c2; 4820 rgbe[2] = (uint8) len; 4821 rgbe[3] = (uint8) get8u(s); 4822 hdr_convert(hdr_data, rgbe, req_comp); 4823 i = 1; 4824 j = 0; 4825 FREE(scanline); 4826 goto main_decode_loop; // yes, this makes no sense 4827 } 4828 len <<= 8; 4829 len |= get8(s); 4830 if (len != width) { FREE(hdr_data); FREE(scanline); return epf("invalid decoded scanline length", "corrupt HDR"); } 4831 if (scanline == NULL) scanline = (stbi_uc *) MALLOC(width * 4); 4832 4833 for (k = 0; k < 4; ++k) { 4834 i = 0; 4835 while (i < width) { 4836 count = get8u(s); 4837 if (count > 128) { 4838 // Run 4839 value = get8u(s); 4840 count -= 128; 4841 for (z = 0; z < count; ++z) 4842 scanline[i++ * 4 + k] = value; 4843 } else { 4844 // Dump 4845 for (z = 0; z < count; ++z) 4846 scanline[i++ * 4 + k] = get8u(s); 4847 } 4848 } 4849 } 4850 for (i=0; i < width; ++i) 4851 hdr_convert(hdr_data+(j*width + i)*req_comp, scanline + i*4, req_comp); 4852 } 4853 FREE(scanline); 4854 } 4855 4856 return hdr_data; 4857} 4858 4859#ifndef STBI_NO_STDIO 4860float *stbi_hdr_load_from_file(FILE *f, int *x, int *y, int *comp, int req_comp) 4861{ 4862 stbi s; 4863 start_file(&s,f); 4864 return hdr_load(&s,x,y,comp,req_comp); 4865} 4866#endif 4867 4868float *stbi_hdr_load_from_memory(stbi_uc const *buffer, int len, int *x, int *y, int *comp, int req_comp) 4869{ 4870 stbi s; 4871 start_mem(&s,buffer, len); 4872 return hdr_load(&s,x,y,comp,req_comp); 4873} 4874 4875#endif // STBI_NO_HDR 4876 4877 4878#ifndef STBI_NO_STDIO 4879int stbi_info(char const *filename, int *x, int *y, int *comp) 4880{ 4881 FILE *f = fopen(filename, "rb"); 4882 int result; 4883 if (!f) return e("can't fopen", "Unable to open file"); 4884 result = stbi_info_from_file(f, x, y, comp); 4885 fclose(f); 4886 return result; 4887} 4888 4889int stbi_info_from_file(FILE *f, int *x, int *y, int *comp) 4890{ 4891 if (stbi_jpeg_info_from_file(f, x, y, comp)) 4892 return 1; 4893 if (stbi_png_info_from_file(f, x, y, comp)) 4894 return 1; 4895 if (stbi_gif_info_from_file(f, x, y, comp)) 4896 return 1; 4897 // @TODO: stbi_bmp_info_from_file 4898 // @TODO: stbi_psd_info_from_file 4899 #ifndef STBI_NO_HDR 4900 // @TODO: stbi_hdr_info_from_file 4901 #endif 4902 // test tga last because it's a crappy test! 4903 if (stbi_tga_info_from_file(f, x, y, comp)) 4904 return 1; 4905 return e("unknown image type", "Image not of any known type, or corrupt"); 4906} 4907#endif // !STBI_NO_STDIO 4908 4909int stbi_info_from_memory(stbi_uc const *buffer, int len, int *x, int *y, int *comp) 4910{ 4911 if (stbi_jpeg_info_from_memory(buffer, len, x, y, comp)) 4912 return 1; 4913 if (stbi_png_info_from_memory(buffer, len, x, y, comp)) 4914 return 1; 4915 if (stbi_gif_info_from_memory(buffer, len, x, y, comp)) 4916 return 1; 4917 // @TODO: stbi_bmp_info_from_memory 4918 // @TODO: stbi_psd_info_from_memory 4919 #ifndef STBI_NO_HDR 4920 // @TODO: stbi_hdr_info_from_memory 4921 #endif 4922 // test tga last because it's a crappy test! 4923 if (stbi_tga_info_from_memory(buffer, len, x, y, comp)) 4924 return 1; 4925 return e("unknown image type", "Image not of any known type, or corrupt"); 4926} 4927 4928#endif // STBI_HEADER_FILE_ONLY 4929 4930/* 4931 revision history: 4932 1.29 (2010-08-16) various warning fixes from Aurelien Pocheville 4933 1.28 (2010-08-01) fix bug in GIF palette transparency (SpartanJ) 4934 1.27 (2010-08-01) 4935 cast-to-uint8 to fix warnings 4936 1.26 (2010-07-24) 4937 fix bug in file buffering for PNG reported by SpartanJ 4938 1.25 (2010-07-17) 4939 refix trans_data warning (Won Chun) 4940 1.24 (2010-07-12) 4941 perf improvements reading from files on platforms with lock-heavy fgetc() 4942 minor perf improvements for jpeg 4943 deprecated type-specific functions so we'll get feedback if they're needed 4944 attempt to fix trans_data warning (Won Chun) 4945 1.23 fixed bug in iPhone support 4946 1.22 (2010-07-10) 4947 removed image *writing* support 4948 removed image *writing* support 4949 stbi_info support from Jetro Lauha 4950 GIF support from Jean-Marc Lienher 4951 iPhone PNG-extensions from James Brown 4952 warning-fixes from Nicolas Schulz and Janez Zemva (i.e. Janez (U+017D)emva) 4953 1.21 fix use of 'uint8' in header (reported by jon blow) 4954 1.20 added support for Softimage PIC, by Tom Seddon 4955 1.19 bug in interlaced PNG corruption check (found by ryg) 4956 1.18 2008-08-02 4957 fix a threading bug (local mutable static) 4958 1.17 support interlaced PNG 4959 1.16 major bugfix - convert_format converted one too many pixels 4960 1.15 initialize some fields for thread safety 4961 1.14 fix threadsafe conversion bug 4962 header-file-only version (#define STBI_HEADER_FILE_ONLY before including) 4963 1.13 threadsafe 4964 1.12 const qualifiers in the API 4965 1.11 Support installable IDCT, colorspace conversion routines 4966 1.10 Fixes for 64-bit (don't use "unsigned long") 4967 optimized upsampling by Fabian "ryg" Giesen 4968 1.09 Fix format-conversion for PSD code (bad global variables!) 4969 1.08 Thatcher Ulrich's PSD code integrated by Nicolas Schulz 4970 1.07 attempt to fix C++ warning/errors again 4971 1.06 attempt to fix C++ warning/errors again 4972 1.05 fix TGA loading to return correct *comp and use good luminance calc 4973 1.04 default float alpha is 1, not 255; use 'void *' for stbi_image_free 4974 1.03 bugfixes to STBI_NO_STDIO, STBI_NO_HDR 4975 1.02 support for (subset of) HDR files, float interface for preferred access to them 4976 1.01 fix bug: possible bug in handling right-side up bmps... not sure 4977 fix bug: the stbi_bmp_load() and stbi_tga_load() functions didn't work at all 4978 1.00 interface to zlib that skips zlib header 4979 0.99 correct handling of alpha in palette 4980 0.98 TGA loader by lonesock; dynamically add loaders (untested) 4981 0.97 jpeg errors on too large a file; also catch another malloc failure 4982 0.96 fix detection of invalid v value - particleman@mollyrocket forum 4983 0.95 during header scan, seek to markers in case of padding 4984 0.94 STBI_NO_STDIO to disable stdio usage; rename all #defines the same 4985 0.93 handle jpegtran output; verbose errors 4986 0.92 read 4,8,16,24,32-bit BMP files of several formats 4987 0.91 output 24-bit Windows 3.0 BMP files 4988 0.90 fix a few more warnings; bump version number to approach 1.0 4989 0.61 bugfixes due to Marc LeBlanc, Christopher Lloyd 4990 0.60 fix compiling as c++ 4991 0.59 fix warnings: merge Dave Moore's -Wall fixes 4992 0.58 fix bug: zlib uncompressed mode len/nlen was wrong endian 4993 0.57 fix bug: jpg last huffman symbol before marker was >9 bits but less 4994 than 16 available 4995 0.56 fix bug: zlib uncompressed mode len vs. nlen 4996 0.55 fix bug: restart_interval not initialized to 0 4997 0.54 allow NULL for 'int *comp' 4998 0.53 fix bug in png 3->4; speedup png decoding 4999 0.52 png handles req_comp=3,4 directly; minor cleanup; jpeg comments 5000 0.51 obey req_comp requests, 1-component jpegs return as 1-component, 5001 on 'test' only check type, not whether we support this variant 5002*/ 5003
