stb_image.c revision 1.4.2.1
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 1 190 191 enum 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 }; 200 201 typedef unsigned char stbi_uc; 202 203 #ifdef __cplusplus 204 extern "C" { 205 #endif 206 207 // PRIMARY API - works on images of any type 208 209 // load image by filename, open file, or memory buffer 210 extern 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 213 extern stbi_uc *stbi_load (char const *filename, int *x, int *y, int *comp, int req_comp); 214 extern 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 235 extern const char *stbi_failure_reason (void); 236 237 // free the loaded image -- this is just free() 238 extern void stbi_image_free (void *retval_from_stbi_load); 239 240 // get image dimensions & components without fully decoding 241 extern int stbi_info_from_memory(stbi_uc const *buffer, int len, int *x, int *y, int *comp); 242 extern int stbi_is_hdr_from_memory(stbi_uc const *buffer, int len); 243 244 #ifndef STBI_NO_STDIO 245 extern int stbi_info (char const *filename, int *x, int *y, int *comp); 246 extern int stbi_info_from_file (FILE *f, int *x, int *y, int *comp); 247 248 extern int stbi_is_hdr (char const *filename); 249 extern 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. 255 extern 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" 259 extern 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 263 264 extern char *stbi_zlib_decode_malloc_guesssize(const char *buffer, int len, int initial_size, int *outlen); 265 extern char *stbi_zlib_decode_malloc_guesssize_headerflag(const char *buffer, int len, int initial_size, int *outlen, int parse_header); 266 extern char *stbi_zlib_decode_malloc(const char *buffer, int len, int *outlen); 267 extern int stbi_zlib_decode_buffer(char *obuffer, int olen, const char *ibuffer, int ilen); 268 269 extern char *stbi_zlib_decode_noheader_malloc(const char *buffer, int len, int *outlen); 270 extern int stbi_zlib_decode_noheader_buffer(char *obuffer, int olen, const char *ibuffer, int ilen); 271 272 // define new loaders 273 typedef 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 286 extern int stbi_register_loader(stbi_loader *loader); 287 288 // define faster low-level operations (typically SIMD support) 289 #ifdef STBI_SIMD 290 typedef 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..255 295 typedef void (*stbi_YCbCr_to_RGB_run)(stbi_uc *output, stbi_uc const *y, stbi_uc const *cb, stbi_uc const *cr, int count, int step); 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..255 302 303 extern void stbi_install_idct(stbi_idct_8x8 func); 304 extern 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? 315 extern int stbi_jpeg_test_memory (stbi_uc const *buffer, int len); 316 extern stbi_uc *stbi_jpeg_load_from_memory(stbi_uc const *buffer, int len, int *x, int *y, int *comp, int req_comp); 317 extern int stbi_jpeg_info_from_memory(stbi_uc const *buffer, int len, int *x, int *y, int *comp); 318 319 #ifndef STBI_NO_STDIO 320 extern stbi_uc *stbi_jpeg_load (char const *filename, int *x, int *y, int *comp, int req_comp); 321 extern int stbi_jpeg_test_file (FILE *f); 322 extern stbi_uc *stbi_jpeg_load_from_file (FILE *f, int *x, int *y, int *comp, int req_comp); 323 324 extern int stbi_jpeg_info (char const *filename, int *x, int *y, int *comp); 325 extern int stbi_jpeg_info_from_file (FILE *f, int *x, int *y, int *comp); 326 #endif 327 328 // is it a png? 329 extern int stbi_png_test_memory (stbi_uc const *buffer, int len); 330 extern stbi_uc *stbi_png_load_from_memory (stbi_uc const *buffer, int len, int *x, int *y, int *comp, int req_comp); 331 extern int stbi_png_info_from_memory (stbi_uc const *buffer, int len, int *x, int *y, int *comp); 332 333 #ifndef STBI_NO_STDIO 334 extern stbi_uc *stbi_png_load (char const *filename, int *x, int *y, int *comp, int req_comp); 335 extern int stbi_png_info (char const *filename, int *x, int *y, int *comp); 336 extern int stbi_png_test_file (FILE *f); 337 extern stbi_uc *stbi_png_load_from_file (FILE *f, int *x, int *y, int *comp, int req_comp); 338 extern int stbi_png_info_from_file (FILE *f, int *x, int *y, int *comp); 339 #endif 340 341 // is it a bmp? 342 extern int stbi_bmp_test_memory (stbi_uc const *buffer, int len); 343 344 extern stbi_uc *stbi_bmp_load (char const *filename, int *x, int *y, int *comp, int req_comp); 345 extern 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 347 extern int stbi_bmp_test_file (FILE *f); 348 extern 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? 352 extern int stbi_tga_test_memory (stbi_uc const *buffer, int len); 353 354 extern stbi_uc *stbi_tga_load (char const *filename, int *x, int *y, int *comp, int req_comp); 355 extern stbi_uc *stbi_tga_load_from_memory (stbi_uc const *buffer, int len, int *x, int *y, int *comp, int req_comp); 356 extern int stbi_tga_info_from_memory (stbi_uc const *buffer, int len, int *x, int *y, int *comp); 357 #ifndef STBI_NO_STDIO 358 extern int stbi_tga_info_from_file (FILE *f, int *x, int *y, int *comp); 359 extern int stbi_tga_test_file (FILE *f); 360 extern 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? 364 extern int stbi_psd_test_memory (stbi_uc const *buffer, int len); 365 366 extern stbi_uc *stbi_psd_load (char const *filename, int *x, int *y, int *comp, int req_comp); 367 extern 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 369 extern int stbi_psd_test_file (FILE *f); 370 extern 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? 374 extern int stbi_hdr_test_memory (stbi_uc const *buffer, int len); 375 376 extern float * stbi_hdr_load (char const *filename, int *x, int *y, int *comp, int req_comp); 377 extern 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 379 extern int stbi_hdr_test_file (FILE *f); 380 extern 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? 384 extern int stbi_pic_test_memory (stbi_uc const *buffer, int len); 385 386 extern stbi_uc *stbi_pic_load (char const *filename, int *x, int *y, int *comp, int req_comp); 387 extern 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 389 extern int stbi_pic_test_file (FILE *f); 390 extern 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? 394 extern int stbi_gif_test_memory (stbi_uc const *buffer, int len); 395 396 extern stbi_uc *stbi_gif_load (char const *filename, int *x, int *y, int *comp, int req_comp); 397 extern stbi_uc *stbi_gif_load_from_memory (stbi_uc const *buffer, int len, int *x, int *y, int *comp, int req_comp); 398 extern int stbi_gif_info_from_memory (stbi_uc const *buffer, int len, int *x, int *y, int *comp); 399 400 #ifndef STBI_NO_STDIO 401 extern int stbi_gif_test_file (FILE *f); 402 extern stbi_uc *stbi_gif_load_from_file (FILE *f, int *x, int *y, int *comp, int req_comp); 403 extern int stbi_gif_info (char const *filename, int *x, int *y, int *comp); 404 extern 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 1.4.2.1 2013/02/25 00:29:32 tls 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) \ 450 do { if (ptr) free((ptr), M_TEMP); } while (/*CONSTCOND*/0) 451 #else 452 #define MALLOC(size) malloc((size)) 453 #define REALLOC(ptr, size) realloc((ptr), (size)) 454 #define FREE(ptr) free((ptr)) 455 #endif 456 457 #ifndef _MSC_VER 458 #ifdef __cplusplus 459 #define __forceinline inline 460 #else 461 #define __forceinline 462 #endif 463 #endif 464 465 466 // implementation: 467 typedef unsigned char uint8; 468 typedef unsigned short uint16; 469 typedef signed short int16; 470 typedef unsigned int uint32; 471 typedef signed int int32; 472 #ifndef __NetBSD__ 473 typedef unsigned int uint; 474 #endif 475 476 // should produce compiler error if size is wrong 477 typedef unsigned char validate_uint32[sizeof(uint32)==4 ? 1 : -1]; 478 479 #if defined(STBI_NO_STDIO) && !defined(STBI_NO_WRITE) 480 #define STBI_NO_WRITE 481 #endif 482 483 #define STBI_NOTUSED(v) v=v 484 485 #ifdef _MSC_VER 486 #define STBI_HAS_LRTOL 487 #endif 488 489 #ifdef STBI_HAS_LRTOL 490 #define stbi_lrot(x,y) _lrotl(x,y) 491 #else 492 #define stbi_lrot(x,y) (((x) << (y)) | ((x) >> (32 - (y)))) 493 #endif 494 495 ////////////////////////////////////////////////////////////////////////////// 496 // 497 // Generic API that works on all image types 498 // 499 500 // deprecated functions 501 502 // is it a jpeg? 503 extern int stbi_jpeg_test_memory (stbi_uc const *buffer, int len); 504 extern stbi_uc *stbi_jpeg_load_from_memory(stbi_uc const *buffer, int len, int *x, int *y, int *comp, int req_comp); 505 extern int stbi_jpeg_info_from_memory(stbi_uc const *buffer, int len, int *x, int *y, int *comp); 506 507 #ifndef STBI_NO_STDIO 508 extern stbi_uc *stbi_jpeg_load (char const *filename, int *x, int *y, int *comp, int req_comp); 509 extern int stbi_jpeg_test_file (FILE *f); 510 extern stbi_uc *stbi_jpeg_load_from_file (FILE *f, int *x, int *y, int *comp, int req_comp); 511 512 extern int stbi_jpeg_info (char const *filename, int *x, int *y, int *comp); 513 extern int stbi_jpeg_info_from_file (FILE *f, int *x, int *y, int *comp); 514 #endif 515 516 // is it a png? 517 extern int stbi_png_test_memory (stbi_uc const *buffer, int len); 518 extern stbi_uc *stbi_png_load_from_memory (stbi_uc const *buffer, int len, int *x, int *y, int *comp, int req_comp); 519 extern int stbi_png_info_from_memory (stbi_uc const *buffer, int len, int *x, int *y, int *comp); 520 521 #ifndef STBI_NO_STDIO 522 extern stbi_uc *stbi_png_load (char const *filename, int *x, int *y, int *comp, int req_comp); 523 extern int stbi_png_info (char const *filename, int *x, int *y, int *comp); 524 extern int stbi_png_test_file (FILE *f); 525 extern stbi_uc *stbi_png_load_from_file (FILE *f, int *x, int *y, int *comp, int req_comp); 526 extern int stbi_png_info_from_file (FILE *f, int *x, int *y, int *comp); 527 #endif 528 529 // is it a bmp? 530 extern int stbi_bmp_test_memory (stbi_uc const *buffer, int len); 531 532 extern stbi_uc *stbi_bmp_load (char const *filename, int *x, int *y, int *comp, int req_comp); 533 extern stbi_uc *stbi_bmp_load_from_memory (stbi_uc const *buffer, int len, int *x, int *y, int *comp, int req_comp); 534 #ifndef STBI_NO_STDIO 535 extern int stbi_bmp_test_file (FILE *f); 536 extern stbi_uc *stbi_bmp_load_from_file (FILE *f, int *x, int *y, int *comp, int req_comp); 537 #endif 538 539 // is it a tga? 540 extern int stbi_tga_test_memory (stbi_uc const *buffer, int len); 541 542 extern stbi_uc *stbi_tga_load (char const *filename, int *x, int *y, int *comp, int req_comp); 543 extern stbi_uc *stbi_tga_load_from_memory (stbi_uc const *buffer, int len, int *x, int *y, int *comp, int req_comp); 544 #ifndef STBI_NO_STDIO 545 extern int stbi_tga_test_file (FILE *f); 546 extern stbi_uc *stbi_tga_load_from_file (FILE *f, int *x, int *y, int *comp, int req_comp); 547 #endif 548 549 // is it a psd? 550 extern int stbi_psd_test_memory (stbi_uc const *buffer, int len); 551 552 extern stbi_uc *stbi_psd_load (char const *filename, int *x, int *y, int *comp, int req_comp); 553 extern stbi_uc *stbi_psd_load_from_memory (stbi_uc const *buffer, int len, int *x, int *y, int *comp, int req_comp); 554 #ifndef STBI_NO_STDIO 555 extern int stbi_psd_test_file (FILE *f); 556 extern stbi_uc *stbi_psd_load_from_file (FILE *f, int *x, int *y, int *comp, int req_comp); 557 #endif 558 559 // is it an hdr? 560 extern int stbi_hdr_test_memory (stbi_uc const *buffer, int len); 561 562 extern float * stbi_hdr_load (char const *filename, int *x, int *y, int *comp, int req_comp); 563 extern float * stbi_hdr_load_from_memory (stbi_uc const *buffer, int len, int *x, int *y, int *comp, int req_comp); 564 #ifndef STBI_NO_STDIO 565 extern int stbi_hdr_test_file (FILE *f); 566 extern float * stbi_hdr_load_from_file (FILE *f, int *x, int *y, int *comp, int req_comp); 567 #endif 568 569 // is it a pic? 570 extern int stbi_pic_test_memory (stbi_uc const *buffer, int len); 571 572 extern stbi_uc *stbi_pic_load (char const *filename, int *x, int *y, int *comp, int req_comp); 573 extern stbi_uc *stbi_pic_load_from_memory (stbi_uc const *buffer, int len, int *x, int *y, int *comp, int req_comp); 574 #ifndef STBI_NO_STDIO 575 extern int stbi_pic_test_file (FILE *f); 576 extern stbi_uc *stbi_pic_load_from_file (FILE *f, int *x, int *y, int *comp, int req_comp); 577 #endif 578 579 // is it a gif? 580 extern int stbi_gif_test_memory (stbi_uc const *buffer, int len); 581 582 extern stbi_uc *stbi_gif_load (char const *filename, int *x, int *y, int *comp, int req_comp); 583 extern stbi_uc *stbi_gif_load_from_memory (stbi_uc const *buffer, int len, int *x, int *y, int *comp, int req_comp); 584 extern int stbi_gif_info_from_memory (stbi_uc const *buffer, int len, int *x, int *y, int *comp); 585 586 #ifndef STBI_NO_STDIO 587 extern int stbi_gif_test_file (FILE *f); 588 extern stbi_uc *stbi_gif_load_from_file (FILE *f, int *x, int *y, int *comp, int req_comp); 589 extern int stbi_gif_info (char const *filename, int *x, int *y, int *comp); 590 extern int stbi_gif_info_from_file (FILE *f, int *x, int *y, int *comp); 591 #endif 592 593 594 // this is not threadsafe 595 static const char *failure_reason; 596 597 const char *stbi_failure_reason(void) 598 { 599 return failure_reason; 600 } 601 602 #ifndef STBI_NO_FAILURE_STRINGS 603 static int e(const char *str) 604 { 605 failure_reason = str; 606 return 0; 607 } 608 #endif 609 610 #ifdef STBI_NO_FAILURE_STRINGS 611 #define e(x,y) 0 612 #elif defined(STBI_FAILURE_USERMSG) 613 #define e(x,y) e(y) 614 #else 615 #define e(x,y) e(x) 616 #endif 617 618 #define epf(x,y) ((float *) (e(x,y)?NULL:NULL)) 619 #define epuc(x,y) ((unsigned char *) (e(x,y)?NULL:NULL)) 620 621 void stbi_image_free(void *retval_from_stbi_load) 622 { 623 FREE(retval_from_stbi_load); 624 } 625 626 #define MAX_LOADERS 32 627 stbi_loader *loaders[MAX_LOADERS]; 628 static int max_loaders = 0; 629 630 int stbi_register_loader(stbi_loader *loader) 631 { 632 int i; 633 for (i=0; i < MAX_LOADERS; ++i) { 634 // already present? 635 if (loaders[i] == loader) 636 return 1; 637 // end of the list? 638 if (loaders[i] == NULL) { 639 loaders[i] = loader; 640 max_loaders = i+1; 641 return 1; 642 } 643 } 644 // no room for it 645 return 0; 646 } 647 648 #ifndef STBI_NO_HDR 649 static float *ldr_to_hdr(stbi_uc *data, int x, int y, int comp); 650 static stbi_uc *hdr_to_ldr(float *data, int x, int y, int comp); 651 #endif 652 653 #ifndef STBI_NO_STDIO 654 unsigned char *stbi_load(char const *filename, int *x, int *y, int *comp, int req_comp) 655 { 656 FILE *f = fopen(filename, "rb"); 657 unsigned char *result; 658 if (!f) return epuc("can't fopen", "Unable to open file"); 659 result = stbi_load_from_file(f,x,y,comp,req_comp); 660 fclose(f); 661 return result; 662 } 663 664 unsigned char *stbi_load_from_file(FILE *f, int *x, int *y, int *comp, int req_comp) 665 { 666 int i; 667 if (stbi_jpeg_test_file(f)) return stbi_jpeg_load_from_file(f,x,y,comp,req_comp); 668 if (stbi_png_test_file(f)) return stbi_png_load_from_file(f,x,y,comp,req_comp); 669 if (stbi_bmp_test_file(f)) return stbi_bmp_load_from_file(f,x,y,comp,req_comp); 670 if (stbi_gif_test_file(f)) return stbi_gif_load_from_file(f,x,y,comp,req_comp); 671 if (stbi_psd_test_file(f)) return stbi_psd_load_from_file(f,x,y,comp,req_comp); 672 if (stbi_pic_test_file(f)) return stbi_pic_load_from_file(f,x,y,comp,req_comp); 673 674 #ifndef STBI_NO_HDR 675 if (stbi_hdr_test_file(f)) { 676 float *hdr = stbi_hdr_load_from_file(f, x,y,comp,req_comp); 677 return hdr_to_ldr(hdr, *x, *y, req_comp ? req_comp : *comp); 678 } 679 #endif 680 681 for (i=0; i < max_loaders; ++i) 682 if (loaders[i]->test_file(f)) 683 return loaders[i]->load_from_file(f,x,y,comp,req_comp); 684 // test tga last because it's a crappy test! 685 if (stbi_tga_test_file(f)) 686 return stbi_tga_load_from_file(f,x,y,comp,req_comp); 687 return epuc("unknown image type", "Image not of any known type, or corrupt"); 688 } 689 #endif 690 691 unsigned char *stbi_load_from_memory(stbi_uc const *buffer, int len, int *x, int *y, int *comp, int req_comp) 692 { 693 int i; 694 if (stbi_jpeg_test_memory(buffer,len)) return stbi_jpeg_load_from_memory(buffer,len,x,y,comp,req_comp); 695 if (stbi_png_test_memory(buffer,len)) return stbi_png_load_from_memory(buffer,len,x,y,comp,req_comp); 696 if (stbi_bmp_test_memory(buffer,len)) return stbi_bmp_load_from_memory(buffer,len,x,y,comp,req_comp); 697 if (stbi_gif_test_memory(buffer,len)) return stbi_gif_load_from_memory(buffer,len,x,y,comp,req_comp); 698 if (stbi_psd_test_memory(buffer,len)) return stbi_psd_load_from_memory(buffer,len,x,y,comp,req_comp); 699 if (stbi_pic_test_memory(buffer,len)) return stbi_pic_load_from_memory(buffer,len,x,y,comp,req_comp); 700 701 #ifndef STBI_NO_HDR 702 if (stbi_hdr_test_memory(buffer, len)) { 703 float *hdr = stbi_hdr_load_from_memory(buffer, len,x,y,comp,req_comp); 704 return hdr_to_ldr(hdr, *x, *y, req_comp ? req_comp : *comp); 705 } 706 #endif 707 708 for (i=0; i < max_loaders; ++i) 709 if (loaders[i]->test_memory(buffer,len)) 710 return loaders[i]->load_from_memory(buffer,len,x,y,comp,req_comp); 711 // test tga last because it's a crappy test! 712 if (stbi_tga_test_memory(buffer,len)) 713 return stbi_tga_load_from_memory(buffer,len,x,y,comp,req_comp); 714 return epuc("unknown image type", "Image not of any known type, or corrupt"); 715 } 716 717 #ifndef STBI_NO_HDR 718 719 #ifndef STBI_NO_STDIO 720 float *stbi_loadf(char const *filename, int *x, int *y, int *comp, int req_comp) 721 { 722 FILE *f = fopen(filename, "rb"); 723 float *result; 724 if (!f) return epf("can't fopen", "Unable to open file"); 725 result = stbi_loadf_from_file(f,x,y,comp,req_comp); 726 fclose(f); 727 return result; 728 } 729 730 float *stbi_loadf_from_file(FILE *f, int *x, int *y, int *comp, int req_comp) 731 { 732 unsigned char *data; 733 #ifndef STBI_NO_HDR 734 if (stbi_hdr_test_file(f)) 735 return stbi_hdr_load_from_file(f,x,y,comp,req_comp); 736 #endif 737 data = stbi_load_from_file(f, x, y, comp, req_comp); 738 if (data) 739 return ldr_to_hdr(data, *x, *y, req_comp ? req_comp : *comp); 740 return epf("unknown image type", "Image not of any known type, or corrupt"); 741 } 742 #endif 743 744 float *stbi_loadf_from_memory(stbi_uc const *buffer, int len, int *x, int *y, int *comp, int req_comp) 745 { 746 stbi_uc *data; 747 #ifndef STBI_NO_HDR 748 if (stbi_hdr_test_memory(buffer, len)) 749 return stbi_hdr_load_from_memory(buffer, len,x,y,comp,req_comp); 750 #endif 751 data = stbi_load_from_memory(buffer, len, x, y, comp, req_comp); 752 if (data) 753 return ldr_to_hdr(data, *x, *y, req_comp ? req_comp : *comp); 754 return epf("unknown image type", "Image not of any known type, or corrupt"); 755 } 756 #endif 757 758 // these is-hdr-or-not is defined independent of whether STBI_NO_HDR is 759 // defined, for API simplicity; if STBI_NO_HDR is defined, it always 760 // reports false! 761 762 int stbi_is_hdr_from_memory(stbi_uc const *buffer, int len) 763 { 764 #ifndef STBI_NO_HDR 765 return stbi_hdr_test_memory(buffer, len); 766 #else 767 STBI_NOTUSED(buffer); 768 STBI_NOTUSED(len); 769 return 0; 770 #endif 771 } 772 773 #ifndef STBI_NO_STDIO 774 extern int stbi_is_hdr (char const *filename) 775 { 776 FILE *f = fopen(filename, "rb"); 777 int result=0; 778 if (f) { 779 result = stbi_is_hdr_from_file(f); 780 fclose(f); 781 } 782 return result; 783 } 784 785 extern int stbi_is_hdr_from_file(FILE *f) 786 { 787 #ifndef STBI_NO_HDR 788 return stbi_hdr_test_file(f); 789 #else 790 return 0; 791 #endif 792 } 793 794 #endif 795 796 #ifndef STBI_NO_HDR 797 static float h2l_gamma_i=1.0f/2.2f, h2l_scale_i=1.0f; 798 static float l2h_gamma=2.2f, l2h_scale=1.0f; 799 800 void stbi_hdr_to_ldr_gamma(float gamma) { h2l_gamma_i = 1/gamma; } 801 void stbi_hdr_to_ldr_scale(float scale) { h2l_scale_i = 1/scale; } 802 803 void stbi_ldr_to_hdr_gamma(float gamma) { l2h_gamma = gamma; } 804 void stbi_ldr_to_hdr_scale(float scale) { l2h_scale = scale; } 805 #endif 806 807 808 ////////////////////////////////////////////////////////////////////////////// 809 // 810 // Common code used by all image loaders 811 // 812 813 enum 814 { 815 SCAN_load=0, 816 SCAN_type, 817 SCAN_header 818 }; 819 820 typedef struct 821 { 822 uint32 img_x, img_y; 823 int img_n, img_out_n; 824 825 #ifndef STBI_NO_STDIO 826 FILE *img_file; 827 int buflen; 828 uint8 buffer_start[128]; 829 int from_file; 830 #endif 831 uint8 const *img_buffer, *img_buffer_end; 832 } stbi; 833 834 #ifndef STBI_NO_STDIO 835 static void start_file(stbi *s, FILE *f) 836 { 837 s->img_file = f; 838 s->buflen = sizeof(s->buffer_start); 839 s->img_buffer_end = s->buffer_start + s->buflen; 840 s->img_buffer = s->img_buffer_end; 841 s->from_file = 1; 842 } 843 #endif 844 845 static void start_mem(stbi *s, uint8 const *buffer, int len) 846 { 847 #ifndef STBI_NO_STDIO 848 s->img_file = NULL; 849 s->from_file = 0; 850 #endif 851 s->img_buffer = (uint8 const *) buffer; 852 s->img_buffer_end = (uint8 const *) buffer+len; 853 } 854 855 #ifndef STBI_NO_STDIO 856 static void refill_buffer(stbi *s) 857 { 858 int n = fread(s->buffer_start, 1, s->buflen, s->img_file); 859 if (n == 0) { 860 s->from_file = 0; 861 s->img_buffer = s->img_buffer_end-1; 862 #if 0 863 *s->img_buffer = 0; 864 #endif 865 } else { 866 s->img_buffer = s->buffer_start; 867 s->img_buffer_end = s->buffer_start + n; 868 } 869 } 870 #endif 871 872 __forceinline static int get8(stbi *s) 873 { 874 if (s->img_buffer < s->img_buffer_end) 875 return *s->img_buffer++; 876 #ifndef STBI_NO_STDIO 877 if (s->from_file) { 878 refill_buffer(s); 879 return *s->img_buffer++; 880 } 881 #endif 882 return 0; 883 } 884 885 __forceinline static int at_eof(stbi *s) 886 { 887 #ifndef STBI_NO_STDIO 888 if (s->img_file) { 889 if (!feof(s->img_file)) return 0; 890 // if feof() is true, check if buffer = end 891 // special case: we've only got the special 0 character at the end 892 if (s->from_file == 0) return 1; 893 } 894 #endif 895 return s->img_buffer >= s->img_buffer_end; 896 } 897 898 __forceinline static uint8 get8u(stbi *s) 899 { 900 return (uint8) get8(s); 901 } 902 903 static void skip(stbi *s, int n) 904 { 905 #ifndef STBI_NO_STDIO 906 if (s->img_file) { 907 int blen = s->img_buffer_end - s->img_buffer; 908 if (blen < n) { 909 s->img_buffer = s->img_buffer_end; 910 fseek(s->img_file, n - blen, SEEK_CUR); 911 return; 912 } 913 } 914 #endif 915 s->img_buffer += n; 916 } 917 918 static int getn(stbi *s, stbi_uc *buffer, int n) 919 { 920 #ifndef STBI_NO_STDIO 921 if (s->img_file) { 922 int blen = s->img_buffer_end - s->img_buffer; 923 if (blen < n) { 924 int res; 925 memcpy(buffer, s->img_buffer, blen); 926 res = ((int) fread(buffer + blen, 1, n - blen, s->img_file) == (n-blen)); 927 s->img_buffer = s->img_buffer_end; 928 return res; 929 } 930 } 931 #endif 932 if (s->img_buffer+n <= s->img_buffer_end) { 933 memcpy(buffer, s->img_buffer, n); 934 s->img_buffer += n; 935 return 1; 936 } else 937 return 0; 938 } 939 940 static int get16(stbi *s) 941 { 942 int z = get8(s); 943 return (z << 8) + get8(s); 944 } 945 946 static uint32 get32(stbi *s) 947 { 948 uint32 z = get16(s); 949 return (z << 16) + get16(s); 950 } 951 952 static int get16le(stbi *s) 953 { 954 int z = get8(s); 955 return z + (get8(s) << 8); 956 } 957 958 static uint32 get32le(stbi *s) 959 { 960 uint32 z = get16le(s); 961 return z + (get16le(s) << 16); 962 } 963 964 ////////////////////////////////////////////////////////////////////////////// 965 // 966 // generic converter from built-in img_n to req_comp 967 // individual types do this automatically as much as possible (e.g. jpeg 968 // does all cases internally since it needs to colorspace convert anyway, 969 // and it never has alpha, so very few cases ). png can automatically 970 // interleave an alpha=255 channel, but falls back to this for other cases 971 // 972 // assume data buffer is malloced, so malloc a new one and free that one 973 // only failure mode is malloc failing 974 975 static uint8 compute_y(int r, int g, int b) 976 { 977 return (uint8) (((r*77) + (g*150) + (29*b)) >> 8); 978 } 979 980 static unsigned char *convert_format(unsigned char *data, int img_n, int req_comp, uint x, uint y) 981 { 982 int i,j; 983 unsigned char *good; 984 985 if (req_comp == img_n) return data; 986 assert(req_comp >= 1 && req_comp <= 4); 987 988 good = (unsigned char *) MALLOC(req_comp * x * y); 989 if (good == NULL) { 990 FREE(data); 991 return epuc("outofmem", "Out of memory"); 992 } 993 994 for (j=0; j < (int) y; ++j) { 995 unsigned char *src = data + j * x * img_n ; 996 unsigned char *dest = good + j * x * req_comp; 997 998 #define COMBO(a,b) ((a)*8+(b)) 999 #define CASE(a,b) case COMBO(a,b): for(i=x-1; i >= 0; --i, src += a, dest += b) 1000 // convert source image with img_n components to one with req_comp components; 1001 // avoid switch per pixel, so use switch per scanline and massive macros 1002 switch (COMBO(img_n, req_comp)) { 1003 CASE(1,2) dest[0]=src[0], dest[1]=255; break; 1004 CASE(1,3) dest[0]=dest[1]=dest[2]=src[0]; break; 1005 CASE(1,4) dest[0]=dest[1]=dest[2]=src[0], dest[3]=255; break; 1006 CASE(2,1) dest[0]=src[0]; break; 1007 CASE(2,3) dest[0]=dest[1]=dest[2]=src[0]; break; 1008 CASE(2,4) dest[0]=dest[1]=dest[2]=src[0], dest[3]=src[1]; break; 1009 CASE(3,4) dest[0]=src[0],dest[1]=src[1],dest[2]=src[2],dest[3]=255; break; 1010 CASE(3,1) dest[0]=compute_y(src[0],src[1],src[2]); break; 1011 CASE(3,2) dest[0]=compute_y(src[0],src[1],src[2]), dest[1] = 255; break; 1012 CASE(4,1) dest[0]=compute_y(src[0],src[1],src[2]); break; 1013 CASE(4,2) dest[0]=compute_y(src[0],src[1],src[2]), dest[1] = src[3]; break; 1014 CASE(4,3) dest[0]=src[0],dest[1]=src[1],dest[2]=src[2]; break; 1015 default: assert(0); 1016 } 1017 #undef CASE 1018 } 1019 1020 FREE(data); 1021 return good; 1022 } 1023 1024 #ifndef STBI_NO_HDR 1025 static float *ldr_to_hdr(stbi_uc *data, int x, int y, int comp) 1026 { 1027 int i,k,n; 1028 float *output = (float *) MALLOC(x * y * comp * sizeof(float)); 1029 if (output == NULL) { FREE(data); return epf("outofmem", "Out of memory"); } 1030 // compute number of non-alpha components 1031 if (comp & 1) n = comp; else n = comp-1; 1032 for (i=0; i < x*y; ++i) { 1033 for (k=0; k < n; ++k) { 1034 output[i*comp + k] = (float) pow(data[i*comp+k]/255.0f, l2h_gamma) * l2h_scale; 1035 } 1036 if (k < comp) output[i*comp + k] = data[i*comp+k]/255.0f; 1037 } 1038 FREE(data); 1039 return output; 1040 } 1041 1042 #define float2int(x) ((int) (x)) 1043 static stbi_uc *hdr_to_ldr(float *data, int x, int y, int comp) 1044 { 1045 int i,k,n; 1046 stbi_uc *output = (stbi_uc *) MALLOC(x * y * comp); 1047 if (output == NULL) { FREE(data); return epuc("outofmem", "Out of memory"); } 1048 // compute number of non-alpha components 1049 if (comp & 1) n = comp; else n = comp-1; 1050 for (i=0; i < x*y; ++i) { 1051 for (k=0; k < n; ++k) { 1052 float z = (float) pow(data[i*comp+k]*h2l_scale_i, h2l_gamma_i) * 255 + 0.5f; 1053 if (z < 0) z = 0; 1054 if (z > 255) z = 255; 1055 output[i*comp + k] = (uint8) float2int(z); 1056 } 1057 if (k < comp) { 1058 float z = data[i*comp+k] * 255 + 0.5f; 1059 if (z < 0) z = 0; 1060 if (z > 255) z = 255; 1061 output[i*comp + k] = (uint8) float2int(z); 1062 } 1063 } 1064 FREE(data); 1065 return output; 1066 } 1067 #endif 1068 1069 ////////////////////////////////////////////////////////////////////////////// 1070 // 1071 // "baseline" JPEG/JFIF decoder (not actually fully baseline implementation) 1072 // 1073 // simple implementation 1074 // - channel subsampling of at most 2 in each dimension 1075 // - doesn't support delayed output of y-dimension 1076 // - simple interface (only one output format: 8-bit interleaved RGB) 1077 // - doesn't try to recover corrupt jpegs 1078 // - doesn't allow partial loading, loading multiple at once 1079 // - still fast on x86 (copying globals into locals doesn't help x86) 1080 // - allocates lots of intermediate memory (full size of all components) 1081 // - non-interleaved case requires this anyway 1082 // - allows good upsampling (see next) 1083 // high-quality 1084 // - upsampled channels are bilinearly interpolated, even across blocks 1085 // - quality integer IDCT derived from IJG's 'slow' 1086 // performance 1087 // - fast huffman; reasonable integer IDCT 1088 // - uses a lot of intermediate memory, could cache poorly 1089 // - load http://nothings.org/remote/anemones.jpg 3 times on 2.8Ghz P4 1090 // stb_jpeg: 1.34 seconds (MSVC6, default release build) 1091 // stb_jpeg: 1.06 seconds (MSVC6, processor = Pentium Pro) 1092 // IJL11.dll: 1.08 seconds (compiled by intel) 1093 // IJG 1998: 0.98 seconds (MSVC6, makefile provided by IJG) 1094 // IJG 1998: 0.95 seconds (MSVC6, makefile + proc=PPro) 1095 1096 // huffman decoding acceleration 1097 #define FAST_BITS 9 // larger handles more cases; smaller stomps less cache 1098 1099 typedef struct 1100 { 1101 uint8 fast[1 << FAST_BITS]; 1102 // weirdly, repacking this into AoS is a 10% speed loss, instead of a win 1103 uint16 code[256]; 1104 uint8 values[256]; 1105 uint8 size[257]; 1106 unsigned int maxcode[18]; 1107 int delta[17]; // old 'firstsymbol' - old 'firstcode' 1108 } huffman; 1109 1110 typedef struct 1111 { 1112 #ifdef STBI_SIMD 1113 unsigned short dequant2[4][64]; 1114 #endif 1115 stbi s; 1116 huffman huff_dc[4]; 1117 huffman huff_ac[4]; 1118 uint8 dequant[4][64]; 1119 1120 // sizes for components, interleaved MCUs 1121 int img_h_max, img_v_max; 1122 int img_mcu_x, img_mcu_y; 1123 int img_mcu_w, img_mcu_h; 1124 1125 // definition of jpeg image component 1126 struct 1127 { 1128 int id; 1129 int h,v; 1130 int tq; 1131 int hd,ha; 1132 int dc_pred; 1133 1134 int x,y,w2,h2; 1135 uint8 *data; 1136 void *raw_data; 1137 uint8 *linebuf; 1138 } img_comp[4]; 1139 1140 uint32 code_buffer; // jpeg entropy-coded buffer 1141 int code_bits; // number of valid bits 1142 unsigned char marker; // marker seen while filling entropy buffer 1143 int nomore; // flag if we saw a marker so must stop 1144 1145 int scan_n, order[4]; 1146 int restart_interval, todo; 1147 } jpeg; 1148 1149 static int build_huffman(huffman *h, int *count) 1150 { 1151 int i,j,k=0,code; 1152 // build size list for each symbol (from JPEG spec) 1153 for (i=0; i < 16; ++i) 1154 for (j=0; j < count[i]; ++j) 1155 h->size[k++] = (uint8) (i+1); 1156 h->size[k] = 0; 1157 1158 // compute actual symbols (from jpeg spec) 1159 code = 0; 1160 k = 0; 1161 for(j=1; j <= 16; ++j) { 1162 // compute delta to add to code to compute symbol id 1163 h->delta[j] = k - code; 1164 if (h->size[k] == j) { 1165 while (h->size[k] == j) 1166 h->code[k++] = (uint16) (code++); 1167 if (code-1 >= (1 << j)) return e("bad code lengths","Corrupt JPEG"); 1168 } 1169 // compute largest code + 1 for this size, preshifted as needed later 1170 h->maxcode[j] = code << (16-j); 1171 code <<= 1; 1172 } 1173 h->maxcode[j] = 0xffffffff; 1174 1175 // build non-spec acceleration table; 255 is flag for not-accelerated 1176 memset(h->fast, 255, 1 << FAST_BITS); 1177 for (i=0; i < k; ++i) { 1178 int s = h->size[i]; 1179 if (s <= FAST_BITS) { 1180 int c = h->code[i] << (FAST_BITS-s); 1181 int m = 1 << (FAST_BITS-s); 1182 for (j=0; j < m; ++j) { 1183 h->fast[c+j] = (uint8) i; 1184 } 1185 } 1186 } 1187 return 1; 1188 } 1189 1190 static void grow_buffer_unsafe(jpeg *j) 1191 { 1192 do { 1193 int b = j->nomore ? 0 : get8(&j->s); 1194 if (b == 0xff) { 1195 int c = get8(&j->s); 1196 if (c != 0) { 1197 j->marker = (unsigned char) c; 1198 j->nomore = 1; 1199 return; 1200 } 1201 } 1202 j->code_buffer |= b << (24 - j->code_bits); 1203 j->code_bits += 8; 1204 } while (j->code_bits <= 24); 1205 } 1206 1207 // (1 << n) - 1 1208 static uint32 bmask[17]={0,1,3,7,15,31,63,127,255,511,1023,2047,4095,8191,16383,32767,65535}; 1209 1210 // decode a jpeg huffman value from the bitstream 1211 __forceinline static int decode(jpeg *j, huffman *h) 1212 { 1213 unsigned int temp; 1214 int c,k; 1215 1216 if (j->code_bits < 16) grow_buffer_unsafe(j); 1217 1218 // look at the top FAST_BITS and determine what symbol ID it is, 1219 // if the code is <= FAST_BITS 1220 c = (j->code_buffer >> (32 - FAST_BITS)) & ((1 << FAST_BITS)-1); 1221 k = h->fast[c]; 1222 if (k < 255) { 1223 int s = h->size[k]; 1224 if (s > j->code_bits) 1225 return -1; 1226 j->code_buffer <<= s; 1227 j->code_bits -= s; 1228 return h->values[k]; 1229 } 1230 1231 // naive test is to shift the code_buffer down so k bits are 1232 // valid, then test against maxcode. To speed this up, we've 1233 // preshifted maxcode left so that it has (16-k) 0s at the 1234 // end; in other words, regardless of the number of bits, it 1235 // wants to be compared against something shifted to have 16; 1236 // that way we don't need to shift inside the loop. 1237 temp = j->code_buffer >> 16; 1238 for (k=FAST_BITS+1 ; ; ++k) 1239 if (temp < h->maxcode[k]) 1240 break; 1241 if (k == 17) { 1242 // error! code not found 1243 j->code_bits -= 16; 1244 return -1; 1245 } 1246 1247 if (k > j->code_bits) 1248 return -1; 1249 1250 // convert the huffman code to the symbol id 1251 c = ((j->code_buffer >> (32 - k)) & bmask[k]) + h->delta[k]; 1252 assert((((j->code_buffer) >> (32 - h->size[c])) & bmask[h->size[c]]) == h->code[c]); 1253 1254 // convert the id to a symbol 1255 j->code_bits -= k; 1256 j->code_buffer <<= k; 1257 return h->values[c]; 1258 } 1259 1260 // combined JPEG 'receive' and JPEG 'extend', since baseline 1261 // always extends everything it receives. 1262 __forceinline static int extend_receive(jpeg *j, int n) 1263 { 1264 unsigned int m = 1 << (n-1); 1265 unsigned int k; 1266 if (j->code_bits < n) grow_buffer_unsafe(j); 1267 1268 #if 1 1269 k = stbi_lrot(j->code_buffer, n); 1270 j->code_buffer = k & ~bmask[n]; 1271 k &= bmask[n]; 1272 j->code_bits -= n; 1273 #else 1274 k = (j->code_buffer >> (32 - n)) & bmask[n]; 1275 j->code_bits -= n; 1276 j->code_buffer <<= n; 1277 #endif 1278 // the following test is probably a random branch that won't 1279 // predict well. I tried to table accelerate it but failed. 1280 // maybe it's compiling as a conditional move? 1281 if (k < m) 1282 return (-1 << n) + k + 1; 1283 else 1284 return k; 1285 } 1286 1287 // given a value that's at position X in the zigzag stream, 1288 // where does it appear in the 8x8 matrix coded as row-major? 1289 static uint8 dezigzag[64+15] = 1290 { 1291 0, 1, 8, 16, 9, 2, 3, 10, 1292 17, 24, 32, 25, 18, 11, 4, 5, 1293 12, 19, 26, 33, 40, 48, 41, 34, 1294 27, 20, 13, 6, 7, 14, 21, 28, 1295 35, 42, 49, 56, 57, 50, 43, 36, 1296 29, 22, 15, 23, 30, 37, 44, 51, 1297 58, 59, 52, 45, 38, 31, 39, 46, 1298 53, 60, 61, 54, 47, 55, 62, 63, 1299 // let corrupt input sample past end 1300 63, 63, 63, 63, 63, 63, 63, 63, 1301 63, 63, 63, 63, 63, 63, 63 1302 }; 1303 1304 // decode one 64-entry block-- 1305 static int decode_block(jpeg *j, short data[64], huffman *hdc, huffman *hac, int b) 1306 { 1307 int diff,dc,k; 1308 int t = decode(j, hdc); 1309 if (t < 0) return e("bad huffman code","Corrupt JPEG"); 1310 1311 // 0 all the ac values now so we can do it 32-bits at a time 1312 memset(data,0,64*sizeof(data[0])); 1313 1314 diff = t ? extend_receive(j, t) : 0; 1315 dc = j->img_comp[b].dc_pred + diff; 1316 j->img_comp[b].dc_pred = dc; 1317 data[0] = (short) dc; 1318 1319 // decode AC components, see JPEG spec 1320 k = 1; 1321 do { 1322 int r,s; 1323 int rs = decode(j, hac); 1324 if (rs < 0) return e("bad huffman code","Corrupt JPEG"); 1325 s = rs & 15; 1326 r = rs >> 4; 1327 if (s == 0) { 1328 if (rs != 0xf0) break; // end block 1329 k += 16; 1330 } else { 1331 k += r; 1332 // decode into unzigzag'd location 1333 data[dezigzag[k++]] = (short) extend_receive(j,s); 1334 } 1335 } while (k < 64); 1336 return 1; 1337 } 1338 1339 // take a -128..127 value and clamp it and convert to 0..255 1340 __forceinline static uint8 clamp(int x) 1341 { 1342 // trick to use a single test to catch both cases 1343 if ((unsigned int) x > 255) { 1344 if (x < 0) return 0; 1345 if (x > 255) return 255; 1346 } 1347 return (uint8) x; 1348 } 1349 1350 #define f2f(x) (int) (((x) * 4096 + 0.5)) 1351 #define fsh(x) ((x) << 12) 1352 1353 // derived from jidctint -- DCT_ISLOW 1354 #define IDCT_1D(s0,s1,s2,s3,s4,s5,s6,s7) \ 1355 int t0,t1,t2,t3,p1,p2,p3,p4,p5,x0,x1,x2,x3; \ 1356 p2 = s2; \ 1357 p3 = s6; \ 1358 p1 = (p2+p3) * f2f(0.5411961f); \ 1359 t2 = p1 + p3*f2f(-1.847759065f); \ 1360 t3 = p1 + p2*f2f( 0.765366865f); \ 1361 p2 = s0; \ 1362 p3 = s4; \ 1363 t0 = fsh(p2+p3); \ 1364 t1 = fsh(p2-p3); \ 1365 x0 = t0+t3; \ 1366 x3 = t0-t3; \ 1367 x1 = t1+t2; \ 1368 x2 = t1-t2; \ 1369 t0 = s7; \ 1370 t1 = s5; \ 1371 t2 = s3; \ 1372 t3 = s1; \ 1373 p3 = t0+t2; \ 1374 p4 = t1+t3; \ 1375 p1 = t0+t3; \ 1376 p2 = t1+t2; \ 1377 p5 = (p3+p4)*f2f( 1.175875602f); \ 1378 t0 = t0*f2f( 0.298631336f); \ 1379 t1 = t1*f2f( 2.053119869f); \ 1380 t2 = t2*f2f( 3.072711026f); \ 1381 t3 = t3*f2f( 1.501321110f); \ 1382 p1 = p5 + p1*f2f(-0.899976223f); \ 1383 p2 = p5 + p2*f2f(-2.562915447f); \ 1384 p3 = p3*f2f(-1.961570560f); \ 1385 p4 = p4*f2f(-0.390180644f); \ 1386 t3 += p1+p4; \ 1387 t2 += p2+p3; \ 1388 t1 += p2+p4; \ 1389 t0 += p1+p3; 1390 1391 #ifdef STBI_SIMD 1392 typedef unsigned short stbi_dequantize_t; 1393 #else 1394 typedef uint8 stbi_dequantize_t; 1395 #endif 1396 1397 // .344 seconds on 3*anemones.jpg 1398 static void idct_block(uint8 *out, int out_stride, short data[64], stbi_dequantize_t *dequantize) 1399 { 1400 int i,val[64],*v=val; 1401 stbi_dequantize_t *dq = dequantize; 1402 uint8 *o; 1403 short *d = data; 1404 1405 // columns 1406 for (i=0; i < 8; ++i,++d,++dq, ++v) { 1407 // if all zeroes, shortcut -- this avoids dequantizing 0s and IDCTing 1408 if (d[ 8]==0 && d[16]==0 && d[24]==0 && d[32]==0 1409 && d[40]==0 && d[48]==0 && d[56]==0) { 1410 // no shortcut 0 seconds 1411 // (1|2|3|4|5|6|7)==0 0 seconds 1412 // all separate -0.047 seconds 1413 // 1 && 2|3 && 4|5 && 6|7: -0.047 seconds 1414 int dcterm = d[0] * dq[0] << 2; 1415 v[0] = v[8] = v[16] = v[24] = v[32] = v[40] = v[48] = v[56] = dcterm; 1416 } else { 1417 IDCT_1D(d[ 0]*dq[ 0],d[ 8]*dq[ 8],d[16]*dq[16],d[24]*dq[24], 1418 d[32]*dq[32],d[40]*dq[40],d[48]*dq[48],d[56]*dq[56]) 1419 // constants scaled things up by 1<<12; let's bring them back 1420 // down, but keep 2 extra bits of precision 1421 x0 += 512; x1 += 512; x2 += 512; x3 += 512; 1422 v[ 0] = (x0+t3) >> 10; 1423 v[56] = (x0-t3) >> 10; 1424 v[ 8] = (x1+t2) >> 10; 1425 v[48] = (x1-t2) >> 10; 1426 v[16] = (x2+t1) >> 10; 1427 v[40] = (x2-t1) >> 10; 1428 v[24] = (x3+t0) >> 10; 1429 v[32] = (x3-t0) >> 10; 1430 } 1431 } 1432 1433 for (i=0, v=val, o=out; i < 8; ++i,v+=8,o+=out_stride) { 1434 // no fast case since the first 1D IDCT spread components out 1435 IDCT_1D(v[0],v[1],v[2],v[3],v[4],v[5],v[6],v[7]) 1436 // constants scaled things up by 1<<12, plus we had 1<<2 from first 1437 // loop, plus horizontal and vertical each scale by sqrt(8) so together 1438 // we've got an extra 1<<3, so 1<<17 total we need to remove. 1439 // so we want to round that, which means adding 0.5 * 1<<17, 1440 // aka 65536. Also, we'll end up with -128 to 127 that we want 1441 // to encode as 0..255 by adding 128, so we'll add that before the shift 1442 x0 += 65536 + (128<<17); 1443 x1 += 65536 + (128<<17); 1444 x2 += 65536 + (128<<17); 1445 x3 += 65536 + (128<<17); 1446 // tried computing the shifts into temps, or'ing the temps to see 1447 // if any were out of range, but that was slower 1448 o[0] = clamp((x0+t3) >> 17); 1449 o[7] = clamp((x0-t3) >> 17); 1450 o[1] = clamp((x1+t2) >> 17); 1451 o[6] = clamp((x1-t2) >> 17); 1452 o[2] = clamp((x2+t1) >> 17); 1453 o[5] = clamp((x2-t1) >> 17); 1454 o[3] = clamp((x3+t0) >> 17); 1455 o[4] = clamp((x3-t0) >> 17); 1456 } 1457 } 1458 1459 #ifdef STBI_SIMD 1460 static stbi_idct_8x8 stbi_idct_installed = idct_block; 1461 1462 extern void stbi_install_idct(stbi_idct_8x8 func) 1463 { 1464 stbi_idct_installed = func; 1465 } 1466 #endif 1467 1468 #define MARKER_none 0xff 1469 // if there's a pending marker from the entropy stream, return that 1470 // otherwise, fetch from the stream and get a marker. if there's no 1471 // marker, return 0xff, which is never a valid marker value 1472 static uint8 get_marker(jpeg *j) 1473 { 1474 uint8 x; 1475 if (j->marker != MARKER_none) { x = j->marker; j->marker = MARKER_none; return x; } 1476 x = get8u(&j->s); 1477 if (x != 0xff) return MARKER_none; 1478 while (x == 0xff) 1479 x = get8u(&j->s); 1480 return x; 1481 } 1482 1483 // in each scan, we'll have scan_n components, and the order 1484 // of the components is specified by order[] 1485 #define RESTART(x) ((x) >= 0xd0 && (x) <= 0xd7) 1486 1487 // after a restart interval, reset the entropy decoder and 1488 // the dc prediction 1489 static void reset(jpeg *j) 1490 { 1491 j->code_bits = 0; 1492 j->code_buffer = 0; 1493 j->nomore = 0; 1494 j->img_comp[0].dc_pred = j->img_comp[1].dc_pred = j->img_comp[2].dc_pred = 0; 1495 j->marker = MARKER_none; 1496 j->todo = j->restart_interval ? j->restart_interval : 0x7fffffff; 1497 // no more than 1<<31 MCUs if no restart_interal? that's plenty safe, 1498 // since we don't even allow 1<<30 pixels 1499 } 1500 1501 static int parse_entropy_coded_data(jpeg *z) 1502 { 1503 reset(z); 1504 if (z->scan_n == 1) { 1505 int i,j; 1506 #ifdef STBI_SIMD 1507 __declspec(align(16)) 1508 #endif 1509 short data[64]; 1510 int n = z->order[0]; 1511 // non-interleaved data, we just need to process one block at a time, 1512 // in trivial scanline order 1513 // number of blocks to do just depends on how many actual "pixels" this 1514 // component has, independent of interleaved MCU blocking and such 1515 int w = (z->img_comp[n].x+7) >> 3; 1516 int h = (z->img_comp[n].y+7) >> 3; 1517 for (j=0; j < h; ++j) { 1518 for (i=0; i < w; ++i) { 1519 if (!decode_block(z, data, z->huff_dc+z->img_comp[n].hd, z->huff_ac+z->img_comp[n].ha, n)) return 0; 1520 #ifdef STBI_SIMD 1521 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]); 1522 #else 1523 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]); 1524 #endif 1525 // every data block is an MCU, so countdown the restart interval 1526 if (--z->todo <= 0) { 1527 if (z->code_bits < 24) grow_buffer_unsafe(z); 1528 // if it's NOT a restart, then just bail, so we get corrupt data 1529 // rather than no data 1530 if (!RESTART(z->marker)) return 1; 1531 reset(z); 1532 } 1533 } 1534 } 1535 } else { // interleaved! 1536 int i,j,k,x,y; 1537 short data[64]; 1538 for (j=0; j < z->img_mcu_y; ++j) { 1539 for (i=0; i < z->img_mcu_x; ++i) { 1540 // scan an interleaved mcu... process scan_n components in order 1541 for (k=0; k < z->scan_n; ++k) { 1542 int n = z->order[k]; 1543 // scan out an mcu's worth of this component; that's just determined 1544 // by the basic H and V specified for the component 1545 for (y=0; y < z->img_comp[n].v; ++y) { 1546 for (x=0; x < z->img_comp[n].h; ++x) { 1547 int x2 = (i*z->img_comp[n].h + x)*8; 1548 int y2 = (j*z->img_comp[n].v + y)*8; 1549 if (!decode_block(z, data, z->huff_dc+z->img_comp[n].hd, z->huff_ac+z->img_comp[n].ha, n)) return 0; 1550 #ifdef STBI_SIMD 1551 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]); 1552 #else 1553 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]); 1554 #endif 1555 } 1556 } 1557 } 1558 // after all interleaved components, that's an interleaved MCU, 1559 // so now count down the restart interval 1560 if (--z->todo <= 0) { 1561 if (z->code_bits < 24) grow_buffer_unsafe(z); 1562 // if it's NOT a restart, then just bail, so we get corrupt data 1563 // rather than no data 1564 if (!RESTART(z->marker)) return 1; 1565 reset(z); 1566 } 1567 } 1568 } 1569 } 1570 return 1; 1571 } 1572 1573 static int process_marker(jpeg *z, int marker) 1574 { 1575 int L; 1576 switch (marker) { 1577 case MARKER_none: // no marker found 1578 return e("expected marker","Corrupt JPEG"); 1579 1580 case 0xC2: // SOF - progressive 1581 return e("progressive jpeg","JPEG format not supported (progressive)"); 1582 1583 case 0xDD: // DRI - specify restart interval 1584 if (get16(&z->s) != 4) return e("bad DRI len","Corrupt JPEG"); 1585 z->restart_interval = get16(&z->s); 1586 return 1; 1587 1588 case 0xDB: // DQT - define quantization table 1589 L = get16(&z->s)-2; 1590 while (L > 0) { 1591 int q = get8(&z->s); 1592 int p = q >> 4; 1593 int t = q & 15,i; 1594 if (p != 0) return e("bad DQT type","Corrupt JPEG"); 1595 if (t > 3) return e("bad DQT table","Corrupt JPEG"); 1596 for (i=0; i < 64; ++i) 1597 z->dequant[t][dezigzag[i]] = get8u(&z->s); 1598 #ifdef STBI_SIMD 1599 for (i=0; i < 64; ++i) 1600 z->dequant2[t][i] = z->dequant[t][i]; 1601 #endif 1602 L -= 65; 1603 } 1604 return L==0; 1605 1606 case 0xC4: // DHT - define huffman table 1607 L = get16(&z->s)-2; 1608 while (L > 0) { 1609 uint8 *v; 1610 int sizes[16],i,m=0; 1611 int q = get8(&z->s); 1612 int tc = q >> 4; 1613 int th = q & 15; 1614 if (tc > 1 || th > 3) return e("bad DHT header","Corrupt JPEG"); 1615 for (i=0; i < 16; ++i) { 1616 sizes[i] = get8(&z->s); 1617 m += sizes[i]; 1618 } 1619 L -= 17; 1620 if (tc == 0) { 1621 if (!build_huffman(z->huff_dc+th, sizes)) return 0; 1622 v = z->huff_dc[th].values; 1623 } else { 1624 if (!build_huffman(z->huff_ac+th, sizes)) return 0; 1625 v = z->huff_ac[th].values; 1626 } 1627 for (i=0; i < m; ++i) 1628 v[i] = get8u(&z->s); 1629 L -= m; 1630 } 1631 return L==0; 1632 } 1633 // check for comment block or APP blocks 1634 if ((marker >= 0xE0 && marker <= 0xEF) || marker == 0xFE) { 1635 skip(&z->s, get16(&z->s)-2); 1636 return 1; 1637 } 1638 return 0; 1639 } 1640 1641 // after we see SOS 1642 static int process_scan_header(jpeg *z) 1643 { 1644 int i; 1645 int Ls = get16(&z->s); 1646 z->scan_n = get8(&z->s); 1647 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"); 1648 if (Ls != 6+2*z->scan_n) return e("bad SOS len","Corrupt JPEG"); 1649 for (i=0; i < z->scan_n; ++i) { 1650 int id = get8(&z->s), which; 1651 int q = get8(&z->s); 1652 for (which = 0; which < z->s.img_n; ++which) 1653 if (z->img_comp[which].id == id) 1654 break; 1655 if (which == z->s.img_n) return 0; 1656 z->img_comp[which].hd = q >> 4; if (z->img_comp[which].hd > 3) return e("bad DC huff","Corrupt JPEG"); 1657 z->img_comp[which].ha = q & 15; if (z->img_comp[which].ha > 3) return e("bad AC huff","Corrupt JPEG"); 1658 z->order[i] = which; 1659 } 1660 if (get8(&z->s) != 0) return e("bad SOS","Corrupt JPEG"); 1661 get8(&z->s); // should be 63, but might be 0 1662 if (get8(&z->s) != 0) return e("bad SOS","Corrupt JPEG"); 1663 1664 return 1; 1665 } 1666 1667 static int process_frame_header(jpeg *z, int scan) 1668 { 1669 stbi *s = &z->s; 1670 int Lf,p,i,q, h_max=1,v_max=1,c; 1671 Lf = get16(s); if (Lf < 11) return e("bad SOF len","Corrupt JPEG"); // JPEG 1672 p = get8(s); if (p != 8) return e("only 8-bit","JPEG format not supported: 8-bit only"); // JPEG baseline 1673 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 1674 s->img_x = get16(s); if (s->img_x == 0) return e("0 width","Corrupt JPEG"); // JPEG requires 1675 c = get8(s); 1676 if (c != 3 && c != 1) return e("bad component count","Corrupt JPEG"); // JFIF requires 1677 s->img_n = c; 1678 for (i=0; i < c; ++i) { 1679 z->img_comp[i].data = NULL; 1680 z->img_comp[i].linebuf = NULL; 1681 } 1682 1683 if (Lf != 8+3*s->img_n) return e("bad SOF len","Corrupt JPEG"); 1684 1685 for (i=0; i < s->img_n; ++i) { 1686 z->img_comp[i].id = get8(s); 1687 if (z->img_comp[i].id != i+1) // JFIF requires 1688 if (z->img_comp[i].id != i) // some version of jpegtran outputs non-JFIF-compliant files! 1689 return e("bad component ID","Corrupt JPEG"); 1690 q = get8(s); 1691 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"); 1692 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"); 1693 z->img_comp[i].tq = get8(s); if (z->img_comp[i].tq > 3) return e("bad TQ","Corrupt JPEG"); 1694 } 1695 1696 if (scan != SCAN_load) return 1; 1697 1698 if ((1 << 30) / s->img_x / s->img_n < s->img_y) return e("too large", "Image too large to decode"); 1699 1700 for (i=0; i < s->img_n; ++i) { 1701 if (z->img_comp[i].h > h_max) h_max = z->img_comp[i].h; 1702 if (z->img_comp[i].v > v_max) v_max = z->img_comp[i].v; 1703 } 1704 1705 // compute interleaved mcu info 1706 z->img_h_max = h_max; 1707 z->img_v_max = v_max; 1708 z->img_mcu_w = h_max * 8; 1709 z->img_mcu_h = v_max * 8; 1710 z->img_mcu_x = (s->img_x + z->img_mcu_w-1) / z->img_mcu_w; 1711 z->img_mcu_y = (s->img_y + z->img_mcu_h-1) / z->img_mcu_h; 1712 1713 for (i=0; i < s->img_n; ++i) { 1714 // number of effective pixels (e.g. for non-interleaved MCU) 1715 z->img_comp[i].x = (s->img_x * z->img_comp[i].h + h_max-1) / h_max; 1716 z->img_comp[i].y = (s->img_y * z->img_comp[i].v + v_max-1) / v_max; 1717 // to simplify generation, we'll allocate enough memory to decode 1718 // the bogus oversized data from using interleaved MCUs and their 1719 // big blocks (e.g. a 16x16 iMCU on an image of width 33); we won't 1720 // discard the extra data until colorspace conversion 1721 z->img_comp[i].w2 = z->img_mcu_x * z->img_comp[i].h * 8; 1722 z->img_comp[i].h2 = z->img_mcu_y * z->img_comp[i].v * 8; 1723 z->img_comp[i].raw_data = MALLOC(z->img_comp[i].w2 * z->img_comp[i].h2+15); 1724 if (z->img_comp[i].raw_data == NULL) { 1725 for(--i; i >= 0; --i) { 1726 FREE(z->img_comp[i].raw_data); 1727 z->img_comp[i].data = NULL; 1728 } 1729 return e("outofmem", "Out of memory"); 1730 } 1731 // align blocks for installable-idct using mmx/sse 1732 z->img_comp[i].data = (uint8*) (((size_t) z->img_comp[i].raw_data + 15) & ~15); 1733 z->img_comp[i].linebuf = NULL; 1734 } 1735 1736 return 1; 1737 } 1738 1739 // use comparisons since in some cases we handle more than one case (e.g. SOF) 1740 #define DNL(x) ((x) == 0xdc) 1741 #define SOI(x) ((x) == 0xd8) 1742 #define EOI(x) ((x) == 0xd9) 1743 #define SOF(x) ((x) == 0xc0 || (x) == 0xc1) 1744 #define SOS(x) ((x) == 0xda) 1745 1746 static int decode_jpeg_header(jpeg *z, int scan) 1747 { 1748 int m; 1749 z->marker = MARKER_none; // initialize cached marker to empty 1750 m = get_marker(z); 1751 if (!SOI(m)) return e("no SOI","Corrupt JPEG"); 1752 if (scan == SCAN_type) return 1; 1753 m = get_marker(z); 1754 while (!SOF(m)) { 1755 if (!process_marker(z,m)) return 0; 1756 m = get_marker(z); 1757 while (m == MARKER_none) { 1758 // some files have extra padding after their blocks, so ok, we'll scan 1759 if (at_eof(&z->s)) return e("no SOF", "Corrupt JPEG"); 1760 m = get_marker(z); 1761 } 1762 } 1763 if (!process_frame_header(z, scan)) return 0; 1764 return 1; 1765 } 1766 1767 static int decode_jpeg_image(jpeg *j) 1768 { 1769 int m; 1770 j->restart_interval = 0; 1771 if (!decode_jpeg_header(j, SCAN_load)) return 0; 1772 m = get_marker(j); 1773 while (!EOI(m)) { 1774 if (SOS(m)) { 1775 if (!process_scan_header(j)) return 0; 1776 if (!parse_entropy_coded_data(j)) return 0; 1777 if (j->marker == MARKER_none ) { 1778 // handle 0s at the end of image data from IP Kamera 9060 1779 while (!at_eof(&j->s)) { 1780 int x = get8(&j->s); 1781 if (x == 255) { 1782 j->marker = get8u(&j->s); 1783 break; 1784 } else if (x != 0) { 1785 return 0; 1786 } 1787 } 1788 // if we reach eof without hitting a marker, get_marker() below will fail and we'll eventually return 0 1789 } 1790 } else { 1791 if (!process_marker(j, m)) return 0; 1792 } 1793 m = get_marker(j); 1794 } 1795 return 1; 1796 } 1797 1798 // static jfif-centered resampling (across block boundaries) 1799 1800 typedef uint8 *(*resample_row_func)(uint8 *out, uint8 *in0, uint8 *in1, 1801 int w, int hs); 1802 1803 #define div4(x) ((uint8) ((x) >> 2)) 1804 1805 static uint8 *resample_row_1(uint8 *out, uint8 *in_near, uint8 *in_far, int w, int hs) 1806 { 1807 STBI_NOTUSED(out); 1808 STBI_NOTUSED(in_far); 1809 STBI_NOTUSED(w); 1810 STBI_NOTUSED(hs); 1811 return in_near; 1812 } 1813 1814 static uint8* resample_row_v_2(uint8 *out, uint8 *in_near, uint8 *in_far, int w, int hs) 1815 { 1816 // need to generate two samples vertically for every one in input 1817 int i; 1818 STBI_NOTUSED(hs); 1819 for (i=0; i < w; ++i) 1820 out[i] = div4(3*in_near[i] + in_far[i] + 2); 1821 return out; 1822 } 1823 1824 static uint8* resample_row_h_2(uint8 *out, uint8 *in_near, uint8 *in_far, int w, int hs) 1825 { 1826 // need to generate two samples horizontally for every one in input 1827 int i; 1828 uint8 *input = in_near; 1829 1830 if (w == 1) { 1831 // if only one sample, can't do any interpolation 1832 out[0] = out[1] = input[0]; 1833 return out; 1834 } 1835 1836 out[0] = input[0]; 1837 out[1] = div4(input[0]*3 + input[1] + 2); 1838 for (i=1; i < w-1; ++i) { 1839 int n = 3*input[i]+2; 1840 out[i*2+0] = div4(n+input[i-1]); 1841 out[i*2+1] = div4(n+input[i+1]); 1842 } 1843 out[i*2+0] = div4(input[w-2]*3 + input[w-1] + 2); 1844 out[i*2+1] = input[w-1]; 1845 1846 STBI_NOTUSED(in_far); 1847 STBI_NOTUSED(hs); 1848 1849 return out; 1850 } 1851 1852 #define div16(x) ((uint8) ((x) >> 4)) 1853 1854 static uint8 *resample_row_hv_2(uint8 *out, uint8 *in_near, uint8 *in_far, int w, int hs) 1855 { 1856 // need to generate 2x2 samples for every one in input 1857 int i,t0,t1; 1858 if (w == 1) { 1859 out[0] = out[1] = div4(3*in_near[0] + in_far[0] + 2); 1860 return out; 1861 } 1862 1863 t1 = 3*in_near[0] + in_far[0]; 1864 out[0] = div4(t1+2); 1865 for (i=1; i < w; ++i) { 1866 t0 = t1; 1867 t1 = 3*in_near[i]+in_far[i]; 1868 out[i*2-1] = div16(3*t0 + t1 + 8); 1869 out[i*2 ] = div16(3*t1 + t0 + 8); 1870 } 1871 out[w*2-1] = div4(t1+2); 1872 1873 STBI_NOTUSED(hs); 1874 1875 return out; 1876 } 1877 1878 static uint8 *resample_row_generic(uint8 *out, uint8 *in_near, uint8 *in_far, int w, int hs) 1879 { 1880 // resample with nearest-neighbor 1881 int i,j; 1882 in_far = in_far; 1883 for (i=0; i < w; ++i) 1884 for (j=0; j < hs; ++j) 1885 out[i*hs+j] = in_near[i]; 1886 return out; 1887 } 1888 1889 #define float2fixed(x) ((int) ((x) * 65536 + 0.5)) 1890 1891 // 0.38 seconds on 3*anemones.jpg (0.25 with processor = Pro) 1892 // VC6 without processor=Pro is generating multiple LEAs per multiply! 1893 static void YCbCr_to_RGB_row(uint8 *out, const uint8 *y, const uint8 *pcb, const uint8 *pcr, int count, int step) 1894 { 1895 int i; 1896 for (i=0; i < count; ++i) { 1897 int y_fixed = (y[i] << 16) + 32768; // rounding 1898 int r,g,b; 1899 int cr = pcr[i] - 128; 1900 int cb = pcb[i] - 128; 1901 r = y_fixed + cr*float2fixed(1.40200f); 1902 g = y_fixed - cr*float2fixed(0.71414f) - cb*float2fixed(0.34414f); 1903 b = y_fixed + cb*float2fixed(1.77200f); 1904 r >>= 16; 1905 g >>= 16; 1906 b >>= 16; 1907 if ((unsigned) r > 255) { if (r < 0) r = 0; else r = 255; } 1908 if ((unsigned) g > 255) { if (g < 0) g = 0; else g = 255; } 1909 if ((unsigned) b > 255) { if (b < 0) b = 0; else b = 255; } 1910 out[0] = (uint8)r; 1911 out[1] = (uint8)g; 1912 out[2] = (uint8)b; 1913 out[3] = 255; 1914 out += step; 1915 } 1916 } 1917 1918 #ifdef STBI_SIMD 1919 static stbi_YCbCr_to_RGB_run stbi_YCbCr_installed = YCbCr_to_RGB_row; 1920 1921 void stbi_install_YCbCr_to_RGB(stbi_YCbCr_to_RGB_run func) 1922 { 1923 stbi_YCbCr_installed = func; 1924 } 1925 #endif 1926 1927 1928 // clean up the temporary component buffers 1929 static void cleanup_jpeg(jpeg *j) 1930 { 1931 int i; 1932 for (i=0; i < j->s.img_n; ++i) { 1933 if (j->img_comp[i].data) { 1934 FREE(j->img_comp[i].raw_data); 1935 j->img_comp[i].data = NULL; 1936 } 1937 if (j->img_comp[i].linebuf) { 1938 FREE(j->img_comp[i].linebuf); 1939 j->img_comp[i].linebuf = NULL; 1940 } 1941 } 1942 } 1943 1944 typedef struct 1945 { 1946 resample_row_func resample; 1947 uint8 *line0,*line1; 1948 int hs,vs; // expansion factor in each axis 1949 int w_lores; // horizontal pixels pre-expansion 1950 int ystep; // how far through vertical expansion we are 1951 int ypos; // which pre-expansion row we're on 1952 } stbi_resample; 1953 1954 static uint8 *load_jpeg_image(jpeg *z, int *out_x, int *out_y, int *comp, int req_comp) 1955 { 1956 int n, decode_n; 1957 // validate req_comp 1958 if (req_comp < 0 || req_comp > 4) return epuc("bad req_comp", "Internal error"); 1959 z->s.img_n = 0; 1960 1961 // load a jpeg image from whichever source 1962 if (!decode_jpeg_image(z)) { cleanup_jpeg(z); return NULL; } 1963 1964 // determine actual number of components to generate 1965 n = req_comp ? req_comp : z->s.img_n; 1966 1967 if (z->s.img_n == 3 && n < 3) 1968 decode_n = 1; 1969 else 1970 decode_n = z->s.img_n; 1971 1972 // resample and color-convert 1973 { 1974 int k; 1975 uint i,j; 1976 uint8 *output; 1977 uint8 *coutput[4]; 1978 1979 stbi_resample res_comp[4]; 1980 1981 for (k=0; k < decode_n; ++k) { 1982 stbi_resample *r = &res_comp[k]; 1983 1984 // allocate line buffer big enough for upsampling off the edges 1985 // with upsample factor of 4 1986 z->img_comp[k].linebuf = (uint8 *) MALLOC(z->s.img_x + 3); 1987 if (!z->img_comp[k].linebuf) { cleanup_jpeg(z); return epuc("outofmem", "Out of memory"); } 1988 1989 r->hs = z->img_h_max / z->img_comp[k].h; 1990 r->vs = z->img_v_max / z->img_comp[k].v; 1991 r->ystep = r->vs >> 1; 1992 r->w_lores = (z->s.img_x + r->hs-1) / r->hs; 1993 r->ypos = 0; 1994 r->line0 = r->line1 = z->img_comp[k].data; 1995 1996 if (r->hs == 1 && r->vs == 1) r->resample = resample_row_1; 1997 else if (r->hs == 1 && r->vs == 2) r->resample = resample_row_v_2; 1998 else if (r->hs == 2 && r->vs == 1) r->resample = resample_row_h_2; 1999 else if (r->hs == 2 && r->vs == 2) r->resample = resample_row_hv_2; 2000 else r->resample = resample_row_generic; 2001 } 2002 2003 // can't error after this so, this is safe 2004 output = (uint8 *) MALLOC(n * z->s.img_x * z->s.img_y + 1); 2005 if (!output) { cleanup_jpeg(z); return epuc("outofmem", "Out of memory"); } 2006 2007 // now go ahead and resample 2008 for (j=0; j < z->s.img_y; ++j) { 2009 uint8 *out = output + n * z->s.img_x * j; 2010 for (k=0; k < decode_n; ++k) { 2011 stbi_resample *r = &res_comp[k]; 2012 int y_bot = r->ystep >= (r->vs >> 1); 2013 coutput[k] = r->resample(z->img_comp[k].linebuf, 2014 y_bot ? r->line1 : r->line0, 2015 y_bot ? r->line0 : r->line1, 2016 r->w_lores, r->hs); 2017 if (++r->ystep >= r->vs) { 2018 r->ystep = 0; 2019 r->line0 = r->line1; 2020 if (++r->ypos < z->img_comp[k].y) 2021 r->line1 += z->img_comp[k].w2; 2022 } 2023 } 2024 if (n >= 3) { 2025 uint8 *y = coutput[0]; 2026 if (z->s.img_n == 3) { 2027 #ifdef STBI_SIMD 2028 stbi_YCbCr_installed(out, y, coutput[1], coutput[2], z->s.img_x, n); 2029 #else 2030 YCbCr_to_RGB_row(out, y, coutput[1], coutput[2], z->s.img_x, n); 2031 #endif 2032 } else 2033 for (i=0; i < z->s.img_x; ++i) { 2034 out[0] = out[1] = out[2] = y[i]; 2035 out[3] = 255; // not used if n==3 2036 out += n; 2037 } 2038 } else { 2039 uint8 *y = coutput[0]; 2040 if (n == 1) 2041 for (i=0; i < z->s.img_x; ++i) out[i] = y[i]; 2042 else 2043 for (i=0; i < z->s.img_x; ++i) *out++ = y[i], *out++ = 255; 2044 } 2045 } 2046 cleanup_jpeg(z); 2047 *out_x = z->s.img_x; 2048 *out_y = z->s.img_y; 2049 if (comp) *comp = z->s.img_n; // report original components, not output 2050 return output; 2051 } 2052 } 2053 2054 #ifndef STBI_NO_STDIO 2055 unsigned char *stbi_jpeg_load_from_file(FILE *f, int *x, int *y, int *comp, int req_comp) 2056 { 2057 jpeg j; 2058 start_file(&j.s, f); 2059 return load_jpeg_image(&j, x,y,comp,req_comp); 2060 } 2061 2062 unsigned char *stbi_jpeg_load(char const *filename, int *x, int *y, int *comp, int req_comp) 2063 { 2064 unsigned char *data; 2065 FILE *f = fopen(filename, "rb"); 2066 if (!f) return NULL; 2067 data = stbi_jpeg_load_from_file(f,x,y,comp,req_comp); 2068 fclose(f); 2069 return data; 2070 } 2071 #endif 2072 2073 unsigned char *stbi_jpeg_load_from_memory(stbi_uc const *buffer, int len, int *x, int *y, int *comp, int req_comp) 2074 { 2075 #ifdef STBI_SMALL_STACK 2076 unsigned char *result; 2077 jpeg *j = (jpeg *) MALLOC(sizeof(*j)); 2078 start_mem(&j->s, buffer, len); 2079 result = load_jpeg_image(j,x,y,comp,req_comp); 2080 FREE(j); 2081 return result; 2082 #else 2083 jpeg j; 2084 start_mem(&j.s, buffer,len); 2085 return load_jpeg_image(&j, x,y,comp,req_comp); 2086 #endif 2087 } 2088 2089 static int stbi_jpeg_info_raw(jpeg *j, int *x, int *y, int *comp) 2090 { 2091 if (!decode_jpeg_header(j, SCAN_header)) 2092 return 0; 2093 if (x) *x = j->s.img_x; 2094 if (y) *y = j->s.img_y; 2095 if (comp) *comp = j->s.img_n; 2096 return 1; 2097 } 2098 2099 #ifndef STBI_NO_STDIO 2100 int stbi_jpeg_test_file(FILE *f) 2101 { 2102 int n,r; 2103 jpeg j; 2104 n = ftell(f); 2105 start_file(&j.s, f); 2106 r = decode_jpeg_header(&j, SCAN_type); 2107 fseek(f,n,SEEK_SET); 2108 return r; 2109 } 2110 2111 int stbi_jpeg_info_from_file(FILE *f, int *x, int *y, int *comp) 2112 { 2113 jpeg j; 2114 long n = ftell(f); 2115 int res; 2116 start_file(&j.s, f); 2117 res = stbi_jpeg_info_raw(&j, x, y, comp); 2118 fseek(f, n, SEEK_SET); 2119 return res; 2120 } 2121 2122 int stbi_jpeg_info(char const *filename, int *x, int *y, int *comp) 2123 { 2124 FILE *f = fopen(filename, "rb"); 2125 int result; 2126 if (!f) return e("can't fopen", "Unable to open file"); 2127 result = stbi_jpeg_info_from_file(f, x, y, comp); 2128 fclose(f); 2129 return result; 2130 } 2131 #endif 2132 2133 int stbi_jpeg_test_memory(stbi_uc const *buffer, int len) 2134 { 2135 jpeg j; 2136 start_mem(&j.s, buffer,len); 2137 return decode_jpeg_header(&j, SCAN_type); 2138 } 2139 2140 int stbi_jpeg_info_from_memory(stbi_uc const *buffer, int len, int *x, int *y, int *comp) 2141 { 2142 jpeg j; 2143 start_mem(&j.s, buffer, len); 2144 return stbi_jpeg_info_raw(&j, x, y, comp); 2145 } 2146 2147 #ifndef STBI_NO_STDIO 2148 extern int stbi_jpeg_info (char const *filename, int *x, int *y, int *comp); 2149 extern int stbi_jpeg_info_from_file (FILE *f, int *x, int *y, int *comp); 2150 #endif 2151 extern int stbi_jpeg_info_from_memory(stbi_uc const *buffer, int len, int *x, int *y, int *comp); 2152 2153 // public domain zlib decode v0.2 Sean Barrett 2006-11-18 2154 // simple implementation 2155 // - all input must be provided in an upfront buffer 2156 // - all output is written to a single output buffer (can malloc/realloc) 2157 // performance 2158 // - fast huffman 2159 2160 // fast-way is faster to check than jpeg huffman, but slow way is slower 2161 #define ZFAST_BITS 9 // accelerate all cases in default tables 2162 #define ZFAST_MASK ((1 << ZFAST_BITS) - 1) 2163 2164 // zlib-style huffman encoding 2165 // (jpegs packs from left, zlib from right, so can't share code) 2166 typedef struct 2167 { 2168 uint16 fast[1 << ZFAST_BITS]; 2169 uint16 firstcode[16]; 2170 int maxcode[17]; 2171 uint16 firstsymbol[16]; 2172 uint8 size[288]; 2173 uint16 value[288]; 2174 } zhuffman; 2175 2176 __forceinline static int bitreverse16(int n) 2177 { 2178 n = ((n & 0xAAAA) >> 1) | ((n & 0x5555) << 1); 2179 n = ((n & 0xCCCC) >> 2) | ((n & 0x3333) << 2); 2180 n = ((n & 0xF0F0) >> 4) | ((n & 0x0F0F) << 4); 2181 n = ((n & 0xFF00) >> 8) | ((n & 0x00FF) << 8); 2182 return n; 2183 } 2184 2185 __forceinline static int bit_reverse(int v, int bits) 2186 { 2187 assert(bits <= 16); 2188 // to bit reverse n bits, reverse 16 and shift 2189 // e.g. 11 bits, bit reverse and shift away 5 2190 return bitreverse16(v) >> (16-bits); 2191 } 2192 2193 static int zbuild_huffman(zhuffman *z, uint8 *sizelist, int num) 2194 { 2195 int i,k=0; 2196 int code, next_code[16], sizes[17]; 2197 2198 // DEFLATE spec for generating codes 2199 memset(sizes, 0, sizeof(sizes)); 2200 memset(z->fast, 255, sizeof(z->fast)); 2201 for (i=0; i < num; ++i) 2202 ++sizes[sizelist[i]]; 2203 sizes[0] = 0; 2204 for (i=1; i < 16; ++i) 2205 assert(sizes[i] <= (1 << i)); 2206 code = 0; 2207 for (i=1; i < 16; ++i) { 2208 next_code[i] = code; 2209 z->firstcode[i] = (uint16) code; 2210 z->firstsymbol[i] = (uint16) k; 2211 code = (code + sizes[i]); 2212 if (sizes[i]) 2213 if (code-1 >= (1 << i)) return e("bad codelengths","Corrupt JPEG"); 2214 z->maxcode[i] = code << (16-i); // preshift for inner loop 2215 code <<= 1; 2216 k += sizes[i]; 2217 } 2218 z->maxcode[16] = 0x10000; // sentinel 2219 for (i=0; i < num; ++i) { 2220 int s = sizelist[i]; 2221 if (s) { 2222 int c = next_code[s] - z->firstcode[s] + z->firstsymbol[s]; 2223 z->size[c] = (uint8)s; 2224 z->value[c] = (uint16)i; 2225 if (s <= ZFAST_BITS) { 2226 int m = bit_reverse(next_code[s],s); 2227 while (m < (1 << ZFAST_BITS)) { 2228 z->fast[m] = (uint16) c; 2229 m += (1 << s); 2230 } 2231 } 2232 ++next_code[s]; 2233 } 2234 } 2235 return 1; 2236 } 2237 2238 // zlib-from-memory implementation for PNG reading 2239 // because PNG allows splitting the zlib stream arbitrarily, 2240 // and it's annoying structurally to have PNG call ZLIB call PNG, 2241 // we require PNG read all the IDATs and combine them into a single 2242 // memory buffer 2243 2244 typedef struct 2245 { 2246 uint8 const *zbuffer, *zbuffer_end; 2247 int num_bits; 2248 uint32 code_buffer; 2249 2250 char *zout; 2251 char *zout_start; 2252 char *zout_end; 2253 int z_expandable; 2254 2255 zhuffman z_length, z_distance; 2256 } zbuf; 2257 2258 __forceinline static int zget8(zbuf *z) 2259 { 2260 if (z->zbuffer >= z->zbuffer_end) return 0; 2261 return *z->zbuffer++; 2262 } 2263 2264 static void fill_bits(zbuf *z) 2265 { 2266 do { 2267 assert(z->code_buffer < (1U << z->num_bits)); 2268 z->code_buffer |= zget8(z) << z->num_bits; 2269 z->num_bits += 8; 2270 } while (z->num_bits <= 24); 2271 } 2272 2273 __forceinline static unsigned int zreceive(zbuf *z, int n) 2274 { 2275 unsigned int k; 2276 if (z->num_bits < n) fill_bits(z); 2277 k = z->code_buffer & ((1 << n) - 1); 2278 z->code_buffer >>= n; 2279 z->num_bits -= n; 2280 return k; 2281 } 2282 2283 __forceinline static int zhuffman_decode(zbuf *a, zhuffman *z) 2284 { 2285 int b,s,k; 2286 if (a->num_bits < 16) fill_bits(a); 2287 b = z->fast[a->code_buffer & ZFAST_MASK]; 2288 if (b < 0xffff) { 2289 s = z->size[b]; 2290 a->code_buffer >>= s; 2291 a->num_bits -= s; 2292 return z->value[b]; 2293 } 2294 2295 // not resolved by fast table, so compute it the slow way 2296 // use jpeg approach, which requires MSbits at top 2297 k = bit_reverse(a->code_buffer, 16); 2298 for (s=ZFAST_BITS+1; ; ++s) 2299 if (k < z->maxcode[s]) 2300 break; 2301 if (s == 16) return -1; // invalid code! 2302 // code size is s, so: 2303 b = (k >> (16-s)) - z->firstcode[s] + z->firstsymbol[s]; 2304 assert(z->size[b] == s); 2305 a->code_buffer >>= s; 2306 a->num_bits -= s; 2307 return z->value[b]; 2308 } 2309 2310 static int expand(zbuf *z, int n) // need to make room for n bytes 2311 { 2312 char *q; 2313 int cur, limit; 2314 if (!z->z_expandable) return e("output buffer limit","Corrupt PNG"); 2315 cur = (int) (z->zout - z->zout_start); 2316 limit = (int) (z->zout_end - z->zout_start); 2317 while (cur + n > limit) 2318 limit *= 2; 2319 q = (char *) REALLOC(z->zout_start, limit); 2320 if (q == NULL) return e("outofmem", "Out of memory"); 2321 z->zout_start = q; 2322 z->zout = q + cur; 2323 z->zout_end = q + limit; 2324 return 1; 2325 } 2326 2327 static int length_base[31] = { 2328 3,4,5,6,7,8,9,10,11,13, 2329 15,17,19,23,27,31,35,43,51,59, 2330 67,83,99,115,131,163,195,227,258,0,0 }; 2331 2332 static int length_extra[31]= 2333 { 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 }; 2334 2335 static int dist_base[32] = { 1,2,3,4,5,7,9,13,17,25,33,49,65,97,129,193, 2336 257,385,513,769,1025,1537,2049,3073,4097,6145,8193,12289,16385,24577,0,0}; 2337 2338 static int dist_extra[32] = 2339 { 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}; 2340 2341 static int parse_huffman_block(zbuf *a) 2342 { 2343 for(;;) { 2344 int z = zhuffman_decode(a, &a->z_length); 2345 if (z < 256) { 2346 if (z < 0) return e("bad huffman code","Corrupt PNG"); // error in huffman codes 2347 if (a->zout >= a->zout_end) if (!expand(a, 1)) return 0; 2348 *a->zout++ = (char) z; 2349 } else { 2350 uint8 *p; 2351 int len,dist; 2352 if (z == 256) return 1; 2353 z -= 257; 2354 len = length_base[z]; 2355 if (length_extra[z]) len += zreceive(a, length_extra[z]); 2356 z = zhuffman_decode(a, &a->z_distance); 2357 if (z < 0) return e("bad huffman code","Corrupt PNG"); 2358 dist = dist_base[z]; 2359 if (dist_extra[z]) dist += zreceive(a, dist_extra[z]); 2360 if (a->zout - a->zout_start < dist) return e("bad dist","Corrupt PNG"); 2361 if (a->zout + len > a->zout_end) if (!expand(a, len)) return 0; 2362 p = (uint8 *) (a->zout - dist); 2363 while (len--) 2364 *a->zout++ = *p++; 2365 } 2366 } 2367 } 2368 2369 static int compute_huffman_codes(zbuf *a) 2370 { 2371 static uint8 length_dezigzag[19] = { 16,17,18,0,8,7,9,6,10,5,11,4,12,3,13,2,14,1,15 }; 2372 zhuffman z_codelength; 2373 uint8 lencodes[286+32+137];//padding for maximum single op 2374 uint8 codelength_sizes[19]; 2375 int i,n; 2376 2377 int hlit = zreceive(a,5) + 257; 2378 int hdist = zreceive(a,5) + 1; 2379 int hclen = zreceive(a,4) + 4; 2380 2381 memset(codelength_sizes, 0, sizeof(codelength_sizes)); 2382 for (i=0; i < hclen; ++i) { 2383 int s = zreceive(a,3); 2384 codelength_sizes[length_dezigzag[i]] = (uint8) s; 2385 } 2386 if (!zbuild_huffman(&z_codelength, codelength_sizes, 19)) return 0; 2387 2388 n = 0; 2389 while (n < hlit + hdist) { 2390 int c = zhuffman_decode(a, &z_codelength); 2391 assert(c >= 0 && c < 19); 2392 if (c < 16) 2393 lencodes[n++] = (uint8) c; 2394 else if (c == 16) { 2395 c = zreceive(a,2)+3; 2396 memset(lencodes+n, lencodes[n-1], c); 2397 n += c; 2398 } else if (c == 17) { 2399 c = zreceive(a,3)+3; 2400 memset(lencodes+n, 0, c); 2401 n += c; 2402 } else { 2403 assert(c == 18); 2404 c = zreceive(a,7)+11; 2405 memset(lencodes+n, 0, c); 2406 n += c; 2407 } 2408 } 2409 if (n != hlit+hdist) return e("bad codelengths","Corrupt PNG"); 2410 if (!zbuild_huffman(&a->z_length, lencodes, hlit)) return 0; 2411 if (!zbuild_huffman(&a->z_distance, lencodes+hlit, hdist)) return 0; 2412 return 1; 2413 } 2414 2415 static int parse_uncompressed_block(zbuf *a) 2416 { 2417 uint8 header[4]; 2418 int len,nlen,k; 2419 if (a->num_bits & 7) 2420 zreceive(a, a->num_bits & 7); // discard 2421 // drain the bit-packed data into header 2422 k = 0; 2423 while (a->num_bits > 0) { 2424 header[k++] = (uint8) (a->code_buffer & 255); // wtf this warns? 2425 a->code_buffer >>= 8; 2426 a->num_bits -= 8; 2427 } 2428 assert(a->num_bits == 0); 2429 // now fill header the normal way 2430 while (k < 4) 2431 header[k++] = (uint8) zget8(a); 2432 len = header[1] * 256 + header[0]; 2433 nlen = header[3] * 256 + header[2]; 2434 if (nlen != (len ^ 0xffff)) return e("zlib corrupt","Corrupt PNG"); 2435 if (a->zbuffer + len > a->zbuffer_end) return e("read past buffer","Corrupt PNG"); 2436 if (a->zout + len > a->zout_end) 2437 if (!expand(a, len)) return 0; 2438 memcpy(a->zout, a->zbuffer, len); 2439 a->zbuffer += len; 2440 a->zout += len; 2441 return 1; 2442 } 2443 2444 static int parse_zlib_header(zbuf *a) 2445 { 2446 int cmf = zget8(a); 2447 int cm = cmf & 15; 2448 /* int cinfo = cmf >> 4; */ 2449 int flg = zget8(a); 2450 if ((cmf*256+flg) % 31 != 0) return e("bad zlib header","Corrupt PNG"); // zlib spec 2451 if (flg & 32) return e("no preset dict","Corrupt PNG"); // preset dictionary not allowed in png 2452 if (cm != 8) return e("bad compression","Corrupt PNG"); // DEFLATE required for png 2453 // window = 1 << (8 + cinfo)... but who cares, we fully buffer output 2454 return 1; 2455 } 2456 2457 // @TODO: should statically initialize these for optimal thread safety 2458 static uint8 default_length[288], default_distance[32]; 2459 static void init_defaults(void) 2460 { 2461 int i; // use <= to match clearly with spec 2462 for (i=0; i <= 143; ++i) default_length[i] = 8; 2463 for ( ; i <= 255; ++i) default_length[i] = 9; 2464 for ( ; i <= 279; ++i) default_length[i] = 7; 2465 for ( ; i <= 287; ++i) default_length[i] = 8; 2466 2467 for (i=0; i <= 31; ++i) default_distance[i] = 5; 2468 } 2469 2470 int stbi_png_partial; // a quick hack to only allow decoding some of a PNG... I should implement real streaming support instead 2471 static int parse_zlib(zbuf *a, int parse_header) 2472 { 2473 int final, type; 2474 if (parse_header) 2475 if (!parse_zlib_header(a)) return 0; 2476 a->num_bits = 0; 2477 a->code_buffer = 0; 2478 do { 2479 final = zreceive(a,1); 2480 type = zreceive(a,2); 2481 if (type == 0) { 2482 if (!parse_uncompressed_block(a)) return 0; 2483 } else if (type == 3) { 2484 return 0; 2485 } else { 2486 if (type == 1) { 2487 // use fixed code lengths 2488 if (!default_distance[31]) init_defaults(); 2489 if (!zbuild_huffman(&a->z_length , default_length , 288)) return 0; 2490 if (!zbuild_huffman(&a->z_distance, default_distance, 32)) return 0; 2491 } else { 2492 if (!compute_huffman_codes(a)) return 0; 2493 } 2494 if (!parse_huffman_block(a)) return 0; 2495 } 2496 if (stbi_png_partial && a->zout - a->zout_start > 65536) 2497 break; 2498 } while (!final); 2499 return 1; 2500 } 2501 2502 static int do_zlib(zbuf *a, char *obuf, int olen, int exp, int parse_header) 2503 { 2504 a->zout_start = obuf; 2505 a->zout = obuf; 2506 a->zout_end = obuf + olen; 2507 a->z_expandable = exp; 2508 2509 return parse_zlib(a, parse_header); 2510 } 2511 2512 char *stbi_zlib_decode_malloc_guesssize(const char * buffer, int len, int initial_size, int *outlen) 2513 { 2514 zbuf a; 2515 char *p = (char *) MALLOC(initial_size); 2516 if (p == NULL) return NULL; 2517 a.zbuffer = (uint8 const *) buffer; 2518 a.zbuffer_end = (uint8 const *) buffer + len; 2519 if (do_zlib(&a, p, initial_size, 1, 1)) { 2520 if (outlen) *outlen = (int) (a.zout - a.zout_start); 2521 return a.zout_start; 2522 } else { 2523 FREE(a.zout_start); 2524 return NULL; 2525 } 2526 } 2527 2528 char *stbi_zlib_decode_malloc(char const *buffer, int len, int *outlen) 2529 { 2530 return stbi_zlib_decode_malloc_guesssize(buffer, len, 16384, outlen); 2531 } 2532 2533 char *stbi_zlib_decode_malloc_guesssize_headerflag(const char *buffer, int len, int initial_size, int *outlen, int parse_header) 2534 { 2535 zbuf a; 2536 char *p = (char *) MALLOC(initial_size); 2537 if (p == NULL) return NULL; 2538 a.zbuffer = (uint8 const *) buffer; 2539 a.zbuffer_end = (uint8 const *) buffer + len; 2540 if (do_zlib(&a, p, initial_size, 1, parse_header)) { 2541 if (outlen) *outlen = (int) (a.zout - a.zout_start); 2542 return a.zout_start; 2543 } else { 2544 FREE(a.zout_start); 2545 return NULL; 2546 } 2547 } 2548 2549 int stbi_zlib_decode_buffer(char *obuffer, int olen, char const *ibuffer, int ilen) 2550 { 2551 zbuf a; 2552 a.zbuffer = (uint8 const *) ibuffer; 2553 a.zbuffer_end = (uint8 const *) ibuffer + ilen; 2554 if (do_zlib(&a, obuffer, olen, 0, 1)) 2555 return (int) (a.zout - a.zout_start); 2556 else 2557 return -1; 2558 } 2559 2560 char *stbi_zlib_decode_noheader_malloc(char const *buffer, int len, int *outlen) 2561 { 2562 zbuf a; 2563 char *p = (char *) MALLOC(16384); 2564 if (p == NULL) return NULL; 2565 a.zbuffer = (uint8 const *) buffer; 2566 a.zbuffer_end = (uint8 const *) buffer+len; 2567 if (do_zlib(&a, p, 16384, 1, 0)) { 2568 if (outlen) *outlen = (int) (a.zout - a.zout_start); 2569 return a.zout_start; 2570 } else { 2571 FREE(a.zout_start); 2572 return NULL; 2573 } 2574 } 2575 2576 int stbi_zlib_decode_noheader_buffer(char *obuffer, int olen, const char *ibuffer, int ilen) 2577 { 2578 zbuf a; 2579 a.zbuffer = (uint8 const *) ibuffer; 2580 a.zbuffer_end = (uint8 const *) ibuffer + ilen; 2581 if (do_zlib(&a, obuffer, olen, 0, 0)) 2582 return (int) (a.zout - a.zout_start); 2583 else 2584 return -1; 2585 } 2586 2587 // public domain "baseline" PNG decoder v0.10 Sean Barrett 2006-11-18 2588 // simple implementation 2589 // - only 8-bit samples 2590 // - no CRC checking 2591 // - allocates lots of intermediate memory 2592 // - avoids problem of streaming data between subsystems 2593 // - avoids explicit window management 2594 // performance 2595 // - uses stb_zlib, a PD zlib implementation with fast huffman decoding 2596 2597 2598 typedef struct 2599 { 2600 uint32 length; 2601 uint32 type; 2602 } chunk; 2603 2604 #define PNG_TYPE(a,b,c,d) (((a) << 24) + ((b) << 16) + ((c) << 8) + (d)) 2605 2606 static chunk get_chunk_header(stbi *s) 2607 { 2608 chunk c; 2609 c.length = get32(s); 2610 c.type = get32(s); 2611 return c; 2612 } 2613 2614 static int check_png_header(stbi *s) 2615 { 2616 static uint8 png_sig[8] = { 137,80,78,71,13,10,26,10 }; 2617 int i; 2618 for (i=0; i < 8; ++i) 2619 if (get8(s) != png_sig[i]) return e("bad png sig","Not a PNG"); 2620 return 1; 2621 } 2622 2623 typedef struct 2624 { 2625 stbi s; 2626 uint8 *idata, *expanded, *out; 2627 } png; 2628 2629 2630 enum { 2631 F_none=0, F_sub=1, F_up=2, F_avg=3, F_paeth=4, 2632 F_avg_first, F_paeth_first 2633 }; 2634 2635 static uint8 first_row_filter[5] = 2636 { 2637 F_none, F_sub, F_none, F_avg_first, F_paeth_first 2638 }; 2639 2640 static int paeth(int a, int b, int c) 2641 { 2642 int p = a + b - c; 2643 int pa = abs(p-a); 2644 int pb = abs(p-b); 2645 int pc = abs(p-c); 2646 if (pa <= pb && pa <= pc) return a; 2647 if (pb <= pc) return b; 2648 return c; 2649 } 2650 2651 // create the png data from post-deflated data 2652 static int create_png_image_raw(png *a, uint8 *raw, uint32 raw_len, int out_n, uint32 x, uint32 y) 2653 { 2654 stbi *s = &a->s; 2655 uint32 i,j,stride = x*out_n; 2656 int k; 2657 int img_n = s->img_n; // copy it into a local for later 2658 assert(out_n == s->img_n || out_n == s->img_n+1); 2659 if (stbi_png_partial) y = 1; 2660 a->out = (uint8 *) MALLOC(x * y * out_n); 2661 if (!a->out) return e("outofmem", "Out of memory"); 2662 if (!stbi_png_partial) { 2663 if (s->img_x == x && s->img_y == y) { 2664 if (raw_len != (img_n * x + 1) * y) return e("not enough pixels","Corrupt PNG"); 2665 } else { // interlaced: 2666 if (raw_len < (img_n * x + 1) * y) return e("not enough pixels","Corrupt PNG"); 2667 } 2668 } 2669 for (j=0; j < y; ++j) { 2670 uint8 *cur = a->out + stride*j; 2671 uint8 *prior = cur - stride; 2672 int filter = *raw++; 2673 if (filter > 4) return e("invalid filter","Corrupt PNG"); 2674 // if first row, use special filter that doesn't sample previous row 2675 if (j == 0) filter = first_row_filter[filter]; 2676 // handle first pixel explicitly 2677 for (k=0; k < img_n; ++k) { 2678 switch (filter) { 2679 case F_none : cur[k] = raw[k]; break; 2680 case F_sub : cur[k] = raw[k]; break; 2681 case F_up : cur[k] = raw[k] + prior[k]; break; 2682 case F_avg : cur[k] = raw[k] + (prior[k]>>1); break; 2683 case F_paeth : cur[k] = (uint8) (raw[k] + paeth(0,prior[k],0)); break; 2684 case F_avg_first : cur[k] = raw[k]; break; 2685 case F_paeth_first: cur[k] = raw[k]; break; 2686 } 2687 } 2688 if (img_n != out_n) cur[img_n] = 255; 2689 raw += img_n; 2690 cur += out_n; 2691 prior += out_n; 2692 // this is a little gross, so that we don't switch per-pixel or per-component 2693 if (img_n == out_n) { 2694 #define CASE(f) \ 2695 case f: \ 2696 for (i=x-1; i >= 1; --i, raw+=img_n,cur+=img_n,prior+=img_n) \ 2697 for (k=0; k < img_n; ++k) 2698 switch (filter) { 2699 CASE(F_none) cur[k] = raw[k]; break; 2700 CASE(F_sub) cur[k] = raw[k] + cur[k-img_n]; break; 2701 CASE(F_up) cur[k] = raw[k] + prior[k]; break; 2702 CASE(F_avg) cur[k] = raw[k] + ((prior[k] + cur[k-img_n])>>1); break; 2703 CASE(F_paeth) cur[k] = (uint8) (raw[k] + paeth(cur[k-img_n],prior[k],prior[k-img_n])); break; 2704 CASE(F_avg_first) cur[k] = raw[k] + (cur[k-img_n] >> 1); break; 2705 CASE(F_paeth_first) cur[k] = (uint8) (raw[k] + paeth(cur[k-img_n],0,0)); break; 2706 } 2707 #undef CASE 2708 } else { 2709 assert(img_n+1 == out_n); 2710 #define CASE(f) \ 2711 case f: \ 2712 for (i=x-1; i >= 1; --i, cur[img_n]=255,raw+=img_n,cur+=out_n,prior+=out_n) \ 2713 for (k=0; k < img_n; ++k) 2714 switch (filter) { 2715 CASE(F_none) cur[k] = raw[k]; break; 2716 CASE(F_sub) cur[k] = raw[k] + cur[k-out_n]; break; 2717 CASE(F_up) cur[k] = raw[k] + prior[k]; break; 2718 CASE(F_avg) cur[k] = raw[k] + ((prior[k] + cur[k-out_n])>>1); break; 2719 CASE(F_paeth) cur[k] = (uint8) (raw[k] + paeth(cur[k-out_n],prior[k],prior[k-out_n])); break; 2720 CASE(F_avg_first) cur[k] = raw[k] + (cur[k-out_n] >> 1); break; 2721 CASE(F_paeth_first) cur[k] = (uint8) (raw[k] + paeth(cur[k-out_n],0,0)); break; 2722 } 2723 #undef CASE 2724 } 2725 } 2726 return 1; 2727 } 2728 2729 static int create_png_image(png *a, uint8 *raw, uint32 raw_len, int out_n, int interlaced) 2730 { 2731 uint8 *final; 2732 int p; 2733 int save; 2734 if (!interlaced) 2735 return create_png_image_raw(a, raw, raw_len, out_n, a->s.img_x, a->s.img_y); 2736 save = stbi_png_partial; 2737 stbi_png_partial = 0; 2738 2739 // de-interlacing 2740 final = (uint8 *) MALLOC(a->s.img_x * a->s.img_y * out_n); 2741 for (p=0; p < 7; ++p) { 2742 int xorig[] = { 0,4,0,2,0,1,0 }; 2743 int yorig[] = { 0,0,4,0,2,0,1 }; 2744 int xspc[] = { 8,8,4,4,2,2,1 }; 2745 int yspc[] = { 8,8,8,4,4,2,2 }; 2746 int i,j,x,y; 2747 // pass1_x[4] = 0, pass1_x[5] = 1, pass1_x[12] = 1 2748 x = (a->s.img_x - xorig[p] + xspc[p]-1) / xspc[p]; 2749 y = (a->s.img_y - yorig[p] + yspc[p]-1) / yspc[p]; 2750 if (x && y) { 2751 if (!create_png_image_raw(a, raw, raw_len, out_n, x, y)) { 2752 FREE(final); 2753 return 0; 2754 } 2755 for (j=0; j < y; ++j) 2756 for (i=0; i < x; ++i) 2757 memcpy(final + (j*yspc[p]+yorig[p])*a->s.img_x*out_n + (i*xspc[p]+xorig[p])*out_n, 2758 a->out + (j*x+i)*out_n, out_n); 2759 FREE(a->out); 2760 raw += (x*out_n+1)*y; 2761 raw_len -= (x*out_n+1)*y; 2762 } 2763 } 2764 a->out = final; 2765 2766 stbi_png_partial = save; 2767 return 1; 2768 } 2769 2770 static int compute_transparency(png *z, uint8 tc[3], int out_n) 2771 { 2772 stbi *s = &z->s; 2773 uint32 i, pixel_count = s->img_x * s->img_y; 2774 uint8 *p = z->out; 2775 2776 // compute color-based transparency, assuming we've 2777 // already got 255 as the alpha value in the output 2778 assert(out_n == 2 || out_n == 4); 2779 2780 if (out_n == 2) { 2781 for (i=0; i < pixel_count; ++i) { 2782 p[1] = (p[0] == tc[0] ? 0 : 255); 2783 p += 2; 2784 } 2785 } else { 2786 for (i=0; i < pixel_count; ++i) { 2787 if (p[0] == tc[0] && p[1] == tc[1] && p[2] == tc[2]) 2788 p[3] = 0; 2789 p += 4; 2790 } 2791 } 2792 return 1; 2793 } 2794 2795 static int expand_palette(png *a, uint8 *palette, int len, int pal_img_n) 2796 { 2797 uint32 i, pixel_count = a->s.img_x * a->s.img_y; 2798 uint8 *p, *temp_out, *orig = a->out; 2799 2800 p = (uint8 *) MALLOC(pixel_count * pal_img_n); 2801 if (p == NULL) return e("outofmem", "Out of memory"); 2802 2803 // between here and FREE(out) below, exiting would leak 2804 temp_out = p; 2805 2806 if (pal_img_n == 3) { 2807 for (i=0; i < pixel_count; ++i) { 2808 int n = orig[i]*4; 2809 p[0] = palette[n ]; 2810 p[1] = palette[n+1]; 2811 p[2] = palette[n+2]; 2812 p += 3; 2813 } 2814 } else { 2815 for (i=0; i < pixel_count; ++i) { 2816 int n = orig[i]*4; 2817 p[0] = palette[n ]; 2818 p[1] = palette[n+1]; 2819 p[2] = palette[n+2]; 2820 p[3] = palette[n+3]; 2821 p += 4; 2822 } 2823 } 2824 FREE(a->out); 2825 a->out = temp_out; 2826 2827 STBI_NOTUSED(len); 2828 2829 return 1; 2830 } 2831 2832 static int stbi_unpremultiply_on_load = 0; 2833 static int stbi_de_iphone_flag = 0; 2834 2835 void stbi_set_unpremultiply_on_load(int flag_true_if_should_unpremultiply) 2836 { 2837 stbi_unpremultiply_on_load = flag_true_if_should_unpremultiply; 2838 } 2839 void stbi_convert_iphone_png_to_rgb(int flag_true_if_should_convert) 2840 { 2841 stbi_de_iphone_flag = flag_true_if_should_convert; 2842 } 2843 2844 static void stbi_de_iphone(png *z) 2845 { 2846 stbi *s = &z->s; 2847 uint32 i, pixel_count = s->img_x * s->img_y; 2848 uint8 *p = z->out; 2849 2850 if (s->img_out_n == 3) { // convert bgr to rgb 2851 for (i=0; i < pixel_count; ++i) { 2852 uint8 t = p[0]; 2853 p[0] = p[2]; 2854 p[2] = t; 2855 p += 3; 2856 } 2857 } else { 2858 assert(s->img_out_n == 4); 2859 if (stbi_unpremultiply_on_load) { 2860 // convert bgr to rgb and unpremultiply 2861 for (i=0; i < pixel_count; ++i) { 2862 uint8 a = p[3]; 2863 uint8 t = p[0]; 2864 if (a) { 2865 p[0] = p[2] * 255 / a; 2866 p[1] = p[1] * 255 / a; 2867 p[2] = t * 255 / a; 2868 } else { 2869 p[0] = p[2]; 2870 p[2] = t; 2871 } 2872 p += 4; 2873 } 2874 } else { 2875 // convert bgr to rgb 2876 for (i=0; i < pixel_count; ++i) { 2877 uint8 t = p[0]; 2878 p[0] = p[2]; 2879 p[2] = t; 2880 p += 4; 2881 } 2882 } 2883 } 2884 } 2885 2886 static int parse_png_file(png *z, int scan, int req_comp) 2887 { 2888 uint8 palette[1024], pal_img_n=0; 2889 uint8 has_trans=0, tc[3]; 2890 uint32 ioff=0, idata_limit=0, i, pal_len=0; 2891 int first=1,k,interlace=0, iphone=0; 2892 stbi *s = &z->s; 2893 2894 if (!check_png_header(s)) return 0; 2895 2896 if (scan == SCAN_type) return 1; 2897 2898 for (;;) { 2899 chunk c = get_chunk_header(s); 2900 switch (c.type) { 2901 case PNG_TYPE('C','g','B','I'): 2902 iphone = stbi_de_iphone_flag; 2903 skip(s, c.length); 2904 break; 2905 case PNG_TYPE('I','H','D','R'): { 2906 int depth,color,comp,filter; 2907 if (!first) return e("multiple IHDR","Corrupt PNG"); 2908 first = 0; 2909 if (c.length != 13) return e("bad IHDR len","Corrupt PNG"); 2910 s->img_x = get32(s); if (s->img_x > (1 << 24)) return e("too large","Very large image (corrupt?)"); 2911 s->img_y = get32(s); if (s->img_y > (1 << 24)) return e("too large","Very large image (corrupt?)"); 2912 depth = get8(s); if (depth != 8) return e("8bit only","PNG not supported: 8-bit only"); 2913 color = get8(s); if (color > 6) return e("bad ctype","Corrupt PNG"); 2914 if (color == 3) pal_img_n = 3; else if (color & 1) return e("bad ctype","Corrupt PNG"); 2915 comp = get8(s); if (comp) return e("bad comp method","Corrupt PNG"); 2916 filter= get8(s); if (filter) return e("bad filter method","Corrupt PNG"); 2917 interlace = get8(s); if (interlace>1) return e("bad interlace method","Corrupt PNG"); 2918 if (!s->img_x || !s->img_y) return e("0-pixel image","Corrupt PNG"); 2919 if (!pal_img_n) { 2920 s->img_n = (color & 2 ? 3 : 1) + (color & 4 ? 1 : 0); 2921 if ((1 << 30) / s->img_x / s->img_n < s->img_y) return e("too large", "Image too large to decode"); 2922 if (scan == SCAN_header) return 1; 2923 } else { 2924 // if paletted, then pal_n is our final components, and 2925 // img_n is # components to decompress/filter. 2926 s->img_n = 1; 2927 if ((1 << 30) / s->img_x / 4 < s->img_y) return e("too large","Corrupt PNG"); 2928 // if SCAN_header, have to scan to see if we have a tRNS 2929 } 2930 break; 2931 } 2932 2933 case PNG_TYPE('P','L','T','E'): { 2934 if (first) return e("first not IHDR", "Corrupt PNG"); 2935 if (c.length > 256*3) return e("invalid PLTE","Corrupt PNG"); 2936 pal_len = c.length / 3; 2937 if (pal_len * 3 != c.length) return e("invalid PLTE","Corrupt PNG"); 2938 for (i=0; i < pal_len; ++i) { 2939 palette[i*4+0] = get8u(s); 2940 palette[i*4+1] = get8u(s); 2941 palette[i*4+2] = get8u(s); 2942 palette[i*4+3] = 255; 2943 } 2944 break; 2945 } 2946 2947 case PNG_TYPE('t','R','N','S'): { 2948 if (first) return e("first not IHDR", "Corrupt PNG"); 2949 if (z->idata) return e("tRNS after IDAT","Corrupt PNG"); 2950 if (pal_img_n) { 2951 if (scan == SCAN_header) { s->img_n = 4; return 1; } 2952 if (pal_len == 0) return e("tRNS before PLTE","Corrupt PNG"); 2953 if (c.length > pal_len) return e("bad tRNS len","Corrupt PNG"); 2954 pal_img_n = 4; 2955 for (i=0; i < c.length; ++i) 2956 palette[i*4+3] = get8u(s); 2957 } else { 2958 if (!(s->img_n & 1)) return e("tRNS with alpha","Corrupt PNG"); 2959 if (c.length != (uint32) s->img_n*2) return e("bad tRNS len","Corrupt PNG"); 2960 has_trans = 1; 2961 for (k=0; k < s->img_n; ++k) 2962 tc[k] = (uint8) get16(s); // non 8-bit images will be larger 2963 } 2964 break; 2965 } 2966 2967 case PNG_TYPE('I','D','A','T'): { 2968 if (first) return e("first not IHDR", "Corrupt PNG"); 2969 if (pal_img_n && !pal_len) return e("no PLTE","Corrupt PNG"); 2970 if (scan == SCAN_header) { s->img_n = pal_img_n; return 1; } 2971 if (ioff + c.length > idata_limit) { 2972 uint8 *p; 2973 if (idata_limit == 0) idata_limit = c.length > 4096 ? c.length : 4096; 2974 while (ioff + c.length > idata_limit) 2975 idata_limit *= 2; 2976 p = (uint8 *) REALLOC(z->idata, idata_limit); if (p == NULL) return e("outofmem", "Out of memory"); 2977 z->idata = p; 2978 } 2979 if (!getn(s, z->idata+ioff,c.length)) return e("outofdata","Corrupt PNG"); 2980 ioff += c.length; 2981 break; 2982 } 2983 2984 case PNG_TYPE('I','E','N','D'): { 2985 uint32 raw_len; 2986 if (first) return e("first not IHDR", "Corrupt PNG"); 2987 if (scan != SCAN_load) return 1; 2988 if (z->idata == NULL) return e("no IDAT","Corrupt PNG"); 2989 z->expanded = (uint8 *) stbi_zlib_decode_malloc_guesssize_headerflag((char *) z->idata, ioff, 16384, (int *) &raw_len, !iphone); 2990 if (z->expanded == NULL) return 0; // zlib should set error 2991 FREE(z->idata); z->idata = NULL; 2992 if ((req_comp == s->img_n+1 && req_comp != 3 && !pal_img_n) || has_trans) 2993 s->img_out_n = s->img_n+1; 2994 else 2995 s->img_out_n = s->img_n; 2996 if (!create_png_image(z, z->expanded, raw_len, s->img_out_n, interlace)) return 0; 2997 if (has_trans) 2998 if (!compute_transparency(z, tc, s->img_out_n)) return 0; 2999 if (iphone && s->img_out_n > 2) 3000 stbi_de_iphone(z); 3001 if (pal_img_n) { 3002 // pal_img_n == 3 or 4 3003 s->img_n = pal_img_n; // record the actual colors we had 3004 s->img_out_n = pal_img_n; 3005 if (req_comp >= 3) s->img_out_n = req_comp; 3006 if (!expand_palette(z, palette, pal_len, s->img_out_n)) 3007 return 0; 3008 } 3009 FREE(z->expanded); z->expanded = NULL; 3010 return 1; 3011 } 3012 3013 default: 3014 // if critical, fail 3015 if (first) return e("first not IHDR", "Corrupt PNG"); 3016 if ((c.type & (1 << 29)) == 0) { 3017 #ifndef STBI_NO_FAILURE_STRINGS 3018 // not threadsafe 3019 static char invalid_chunk[] = "XXXX chunk not known"; 3020 invalid_chunk[0] = (uint8) (c.type >> 24); 3021 invalid_chunk[1] = (uint8) (c.type >> 16); 3022 invalid_chunk[2] = (uint8) (c.type >> 8); 3023 invalid_chunk[3] = (uint8) (c.type >> 0); 3024 #endif 3025 return e(invalid_chunk, "PNG not supported: unknown chunk type"); 3026 } 3027 skip(s, c.length); 3028 break; 3029 } 3030 // end of chunk, read and skip CRC 3031 get32(s); 3032 } 3033 } 3034 3035 static unsigned char *do_png(png *p, int *x, int *y, int *n, int req_comp) 3036 { 3037 unsigned char *result=NULL; 3038 p->expanded = NULL; 3039 p->idata = NULL; 3040 p->out = NULL; 3041 if (req_comp < 0 || req_comp > 4) return epuc("bad req_comp", "Internal error"); 3042 if (parse_png_file(p, SCAN_load, req_comp)) { 3043 result = p->out; 3044 p->out = NULL; 3045 if (req_comp && req_comp != p->s.img_out_n) { 3046 result = convert_format(result, p->s.img_out_n, req_comp, p->s.img_x, p->s.img_y); 3047 p->s.img_out_n = req_comp; 3048 if (result == NULL) return result; 3049 } 3050 *x = p->s.img_x; 3051 *y = p->s.img_y; 3052 if (n) *n = p->s.img_n; 3053 } 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 3061 unsigned 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 3068 unsigned 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 3079 unsigned 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 3087 int 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 3099 int 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 3106 static 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 3117 int 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 3127 int 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 3139 int 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 3148 static 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 3163 int 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 3174 int 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 3182 static 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 3194 static 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 3204 static 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 3221 static 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 3417 stbi_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 3427 stbi_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 3435 stbi_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 3445 static 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 3475 int 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 3487 int 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 3494 static 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 3515 int 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 3526 int 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 3533 static 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 3755 stbi_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 3765 stbi_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 3773 stbi_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 3784 static 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 3791 int 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 3802 int 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 3809 static 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 3968 stbi_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 3978 stbi_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 3986 stbi_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 4000 static 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 4010 static 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 4026 typedef struct 4027 { 4028 stbi_uc size,type,channel; 4029 } pic_packet_t; 4030 4031 static 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 4045 static 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 4054 static 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 4164 static 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 4197 int 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 4204 stbi_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 4212 int 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 4223 stbi_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 4233 stbi_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 4243 typedef struct stbi_gif_lzw_struct { 4244 int16 prefix; 4245 uint8 first; 4246 uint8 suffix; 4247 } stbi_gif_lzw; 4248 4249 typedef 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 4266 static 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 4277 int 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 4288 int 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 4295 static 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 4306 static 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 4334 static 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 4343 static 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 4377 static 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 4456 static 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 4471 static 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 4572 stbi_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 4582 stbi_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 4600 stbi_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 4632 int 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 4642 int 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 4654 int 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 4668 static 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 4678 int 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 4686 int 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 4698 static 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 4720 static 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 4748 static 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 4860 float *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 4868 float *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 4879 int 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 4889 int 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 4909 int 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
Indexes created Thu Oct 02 01:09:59 GMT 2025