stb_image_write.h (71221B)
1 /* stb_image_write - v1.16 - public domain - http://nothings.org/stb 2 writes out PNG/BMP/TGA/JPEG/HDR images to C stdio - Sean Barrett 2010-2015 3 no warranty implied; use at your own risk 4 5 Before #including, 6 7 #define STB_IMAGE_WRITE_IMPLEMENTATION 8 9 in the file that you want to have the implementation. 10 11 Will probably not work correctly with strict-aliasing optimizations. 12 13 ABOUT: 14 15 This header file is a library for writing images to C stdio or a callback. 16 17 The PNG output is not optimal; it is 20-50% larger than the file 18 written by a decent optimizing implementation; though providing a custom 19 zlib compress function (see STBIW_ZLIB_COMPRESS) can mitigate that. 20 This library is designed for source code compactness and simplicity, 21 not optimal image file size or run-time performance. 22 23 BUILDING: 24 25 You can #define STBIW_ASSERT(x) before the #include to avoid using assert.h. 26 You can #define STBIW_MALLOC(), STBIW_REALLOC(), and STBIW_FREE() to replace 27 malloc,realloc,free. 28 You can #define STBIW_MEMMOVE() to replace memmove() 29 You can #define STBIW_ZLIB_COMPRESS to use a custom zlib-style compress function 30 for PNG compression (instead of the builtin one), it must have the following signature: 31 unsigned char * my_compress(unsigned char *data, int data_len, int *out_len, int quality); 32 The returned data will be freed with STBIW_FREE() (free() by default), 33 so it must be heap allocated with STBIW_MALLOC() (malloc() by default), 34 35 UNICODE: 36 37 If compiling for Windows and you wish to use Unicode filenames, compile 38 with 39 #define STBIW_WINDOWS_UTF8 40 and pass utf8-encoded filenames. Call stbiw_convert_wchar_to_utf8 to convert 41 Windows wchar_t filenames to utf8. 42 43 USAGE: 44 45 There are five functions, one for each image file format: 46 47 int stbi_write_png(char const *filename, int w, int h, int comp, const void *data, int stride_in_bytes); 48 int stbi_write_bmp(char const *filename, int w, int h, int comp, const void *data); 49 int stbi_write_tga(char const *filename, int w, int h, int comp, const void *data); 50 int stbi_write_jpg(char const *filename, int w, int h, int comp, const void *data, int quality); 51 int stbi_write_hdr(char const *filename, int w, int h, int comp, const float *data); 52 53 void stbi_flip_vertically_on_write(int flag); // flag is non-zero to flip data vertically 54 55 There are also five equivalent functions that use an arbitrary write function. You are 56 expected to open/close your file-equivalent before and after calling these: 57 58 int stbi_write_png_to_func(stbi_write_func *func, void *context, int w, int h, int comp, const void *data, int stride_in_bytes); 59 int stbi_write_bmp_to_func(stbi_write_func *func, void *context, int w, int h, int comp, const void *data); 60 int stbi_write_tga_to_func(stbi_write_func *func, void *context, int w, int h, int comp, const void *data); 61 int stbi_write_hdr_to_func(stbi_write_func *func, void *context, int w, int h, int comp, const float *data); 62 int stbi_write_jpg_to_func(stbi_write_func *func, void *context, int x, int y, int comp, const void *data, int quality); 63 64 where the callback is: 65 void stbi_write_func(void *context, void *data, int size); 66 67 You can configure it with these global variables: 68 int stbi_write_tga_with_rle; // defaults to true; set to 0 to disable RLE 69 int stbi_write_png_compression_level; // defaults to 8; set to higher for more compression 70 int stbi_write_force_png_filter; // defaults to -1; set to 0..5 to force a filter mode 71 72 73 You can define STBI_WRITE_NO_STDIO to disable the file variant of these 74 functions, so the library will not use stdio.h at all. However, this will 75 also disable HDR writing, because it requires stdio for formatted output. 76 77 Each function returns 0 on failure and non-0 on success. 78 79 The functions create an image file defined by the parameters. The image 80 is a rectangle of pixels stored from left-to-right, top-to-bottom. 81 Each pixel contains 'comp' channels of data stored interleaved with 8-bits 82 per channel, in the following order: 1=Y, 2=YA, 3=RGB, 4=RGBA. (Y is 83 monochrome color.) The rectangle is 'w' pixels wide and 'h' pixels tall. 84 The *data pointer points to the first byte of the top-left-most pixel. 85 For PNG, "stride_in_bytes" is the distance in bytes from the first byte of 86 a row of pixels to the first byte of the next row of pixels. 87 88 PNG creates output files with the same number of components as the input. 89 The BMP format expands Y to RGB in the file format and does not 90 output alpha. 91 92 PNG supports writing rectangles of data even when the bytes storing rows of 93 data are not consecutive in memory (e.g. sub-rectangles of a larger image), 94 by supplying the stride between the beginning of adjacent rows. The other 95 formats do not. (Thus you cannot write a native-format BMP through the BMP 96 writer, both because it is in BGR order and because it may have padding 97 at the end of the line.) 98 99 PNG allows you to set the deflate compression level by setting the global 100 variable 'stbi_write_png_compression_level' (it defaults to 8). 101 102 HDR expects linear float data. Since the format is always 32-bit rgb(e) 103 data, alpha (if provided) is discarded, and for monochrome data it is 104 replicated across all three channels. 105 106 TGA supports RLE or non-RLE compressed data. To use non-RLE-compressed 107 data, set the global variable 'stbi_write_tga_with_rle' to 0. 108 109 JPEG does ignore alpha channels in input data; quality is between 1 and 100. 110 Higher quality looks better but results in a bigger image. 111 JPEG baseline (no JPEG progressive). 112 113 CREDITS: 114 115 116 Sean Barrett - PNG/BMP/TGA 117 Baldur Karlsson - HDR 118 Jean-Sebastien Guay - TGA monochrome 119 Tim Kelsey - misc enhancements 120 Alan Hickman - TGA RLE 121 Emmanuel Julien - initial file IO callback implementation 122 Jon Olick - original jo_jpeg.cpp code 123 Daniel Gibson - integrate JPEG, allow external zlib 124 Aarni Koskela - allow choosing PNG filter 125 126 bugfixes: 127 github:Chribba 128 Guillaume Chereau 129 github:jry2 130 github:romigrou 131 Sergio Gonzalez 132 Jonas Karlsson 133 Filip Wasil 134 Thatcher Ulrich 135 github:poppolopoppo 136 Patrick Boettcher 137 github:xeekworx 138 Cap Petschulat 139 Simon Rodriguez 140 Ivan Tikhonov 141 github:ignotion 142 Adam Schackart 143 Andrew Kensler 144 145 LICENSE 146 147 See end of file for license information. 148 149 */ 150 151 #ifndef INCLUDE_STB_IMAGE_WRITE_H 152 #define INCLUDE_STB_IMAGE_WRITE_H 153 154 #include <stdlib.h> 155 156 // if STB_IMAGE_WRITE_STATIC causes problems, try defining STBIWDEF to 'inline' or 'static inline' 157 #ifndef STBIWDEF 158 #ifdef STB_IMAGE_WRITE_STATIC 159 #define STBIWDEF static 160 #else 161 #ifdef __cplusplus 162 #define STBIWDEF extern "C" 163 #else 164 #define STBIWDEF extern 165 #endif 166 #endif 167 #endif 168 169 #ifndef STB_IMAGE_WRITE_STATIC // C++ forbids static forward declarations 170 STBIWDEF int stbi_write_tga_with_rle; 171 STBIWDEF int stbi_write_png_compression_level; 172 STBIWDEF int stbi_write_force_png_filter; 173 #endif 174 175 #ifndef STBI_WRITE_NO_STDIO 176 STBIWDEF int stbi_write_png(char const *filename, int w, int h, int comp, const void *data, int stride_in_bytes); 177 STBIWDEF int stbi_write_bmp(char const *filename, int w, int h, int comp, const void *data); 178 STBIWDEF int stbi_write_tga(char const *filename, int w, int h, int comp, const void *data); 179 STBIWDEF int stbi_write_hdr(char const *filename, int w, int h, int comp, const float *data); 180 STBIWDEF int stbi_write_jpg(char const *filename, int x, int y, int comp, const void *data, int quality); 181 182 #ifdef STBIW_WINDOWS_UTF8 183 STBIWDEF int stbiw_convert_wchar_to_utf8(char *buffer, size_t bufferlen, const wchar_t* input); 184 #endif 185 #endif 186 187 typedef void stbi_write_func(void *context, void *data, int size); 188 189 STBIWDEF int stbi_write_png_to_func(stbi_write_func *func, void *context, int w, int h, int comp, const void *data, int stride_in_bytes); 190 STBIWDEF int stbi_write_bmp_to_func(stbi_write_func *func, void *context, int w, int h, int comp, const void *data); 191 STBIWDEF int stbi_write_tga_to_func(stbi_write_func *func, void *context, int w, int h, int comp, const void *data); 192 STBIWDEF int stbi_write_hdr_to_func(stbi_write_func *func, void *context, int w, int h, int comp, const float *data); 193 STBIWDEF int stbi_write_jpg_to_func(stbi_write_func *func, void *context, int x, int y, int comp, const void *data, int quality); 194 195 STBIWDEF void stbi_flip_vertically_on_write(int flip_boolean); 196 197 #endif//INCLUDE_STB_IMAGE_WRITE_H 198 199 #ifdef STB_IMAGE_WRITE_IMPLEMENTATION 200 201 #ifdef _WIN32 202 #ifndef _CRT_SECURE_NO_WARNINGS 203 #define _CRT_SECURE_NO_WARNINGS 204 #endif 205 #ifndef _CRT_NONSTDC_NO_DEPRECATE 206 #define _CRT_NONSTDC_NO_DEPRECATE 207 #endif 208 #endif 209 210 #ifndef STBI_WRITE_NO_STDIO 211 #include <stdio.h> 212 #endif // STBI_WRITE_NO_STDIO 213 214 #include <stdarg.h> 215 #include <stdlib.h> 216 #include <string.h> 217 #include <math.h> 218 219 #if defined(STBIW_MALLOC) && defined(STBIW_FREE) && (defined(STBIW_REALLOC) || defined(STBIW_REALLOC_SIZED)) 220 // ok 221 #elif !defined(STBIW_MALLOC) && !defined(STBIW_FREE) && !defined(STBIW_REALLOC) && !defined(STBIW_REALLOC_SIZED) 222 // ok 223 #else 224 #error "Must define all or none of STBIW_MALLOC, STBIW_FREE, and STBIW_REALLOC (or STBIW_REALLOC_SIZED)." 225 #endif 226 227 #ifndef STBIW_MALLOC 228 #define STBIW_MALLOC(sz) malloc(sz) 229 #define STBIW_REALLOC(p,newsz) realloc(p,newsz) 230 #define STBIW_FREE(p) free(p) 231 #endif 232 233 #ifndef STBIW_REALLOC_SIZED 234 #define STBIW_REALLOC_SIZED(p,oldsz,newsz) STBIW_REALLOC(p,newsz) 235 #endif 236 237 238 #ifndef STBIW_MEMMOVE 239 #define STBIW_MEMMOVE(a,b,sz) memmove(a,b,sz) 240 #endif 241 242 243 #ifndef STBIW_ASSERT 244 #include <assert.h> 245 #define STBIW_ASSERT(x) assert(x) 246 #endif 247 248 #define STBIW_UCHAR(x) (unsigned char) ((x) & 0xff) 249 250 #ifdef STB_IMAGE_WRITE_STATIC 251 static int stbi_write_png_compression_level = 8; 252 static int stbi_write_tga_with_rle = 1; 253 static int stbi_write_force_png_filter = -1; 254 #else 255 int stbi_write_png_compression_level = 8; 256 int stbi_write_tga_with_rle = 1; 257 int stbi_write_force_png_filter = -1; 258 #endif 259 260 static int stbi__flip_vertically_on_write = 0; 261 262 STBIWDEF void stbi_flip_vertically_on_write(int flag) 263 { 264 stbi__flip_vertically_on_write = flag; 265 } 266 267 typedef struct 268 { 269 stbi_write_func *func; 270 void *context; 271 unsigned char buffer[64]; 272 int buf_used; 273 } stbi__write_context; 274 275 // initialize a callback-based context 276 static void stbi__start_write_callbacks(stbi__write_context *s, stbi_write_func *c, void *context) 277 { 278 s->func = c; 279 s->context = context; 280 } 281 282 #ifndef STBI_WRITE_NO_STDIO 283 284 static void stbi__stdio_write(void *context, void *data, int size) 285 { 286 fwrite(data,1,size,(FILE*) context); 287 } 288 289 #if defined(_WIN32) && defined(STBIW_WINDOWS_UTF8) 290 #ifdef __cplusplus 291 #define STBIW_EXTERN extern "C" 292 #else 293 #define STBIW_EXTERN extern 294 #endif 295 STBIW_EXTERN __declspec(dllimport) int __stdcall MultiByteToWideChar(unsigned int cp, unsigned long flags, const char *str, int cbmb, wchar_t *widestr, int cchwide); 296 STBIW_EXTERN __declspec(dllimport) int __stdcall WideCharToMultiByte(unsigned int cp, unsigned long flags, const wchar_t *widestr, int cchwide, char *str, int cbmb, const char *defchar, int *used_default); 297 298 STBIWDEF int stbiw_convert_wchar_to_utf8(char *buffer, size_t bufferlen, const wchar_t* input) 299 { 300 return WideCharToMultiByte(65001 /* UTF8 */, 0, input, -1, buffer, (int) bufferlen, NULL, NULL); 301 } 302 #endif 303 304 static FILE *stbiw__fopen(char const *filename, char const *mode) 305 { 306 FILE *f; 307 #if defined(_WIN32) && defined(STBIW_WINDOWS_UTF8) 308 wchar_t wMode[64]; 309 wchar_t wFilename[1024]; 310 if (0 == MultiByteToWideChar(65001 /* UTF8 */, 0, filename, -1, wFilename, sizeof(wFilename)/sizeof(*wFilename))) 311 return 0; 312 313 if (0 == MultiByteToWideChar(65001 /* UTF8 */, 0, mode, -1, wMode, sizeof(wMode)/sizeof(*wMode))) 314 return 0; 315 316 #if defined(_MSC_VER) && _MSC_VER >= 1400 317 if (0 != _wfopen_s(&f, wFilename, wMode)) 318 f = 0; 319 #else 320 f = _wfopen(wFilename, wMode); 321 #endif 322 323 #elif defined(_MSC_VER) && _MSC_VER >= 1400 324 if (0 != fopen_s(&f, filename, mode)) 325 f=0; 326 #else 327 f = fopen(filename, mode); 328 #endif 329 return f; 330 } 331 332 static int stbi__start_write_file(stbi__write_context *s, const char *filename) 333 { 334 FILE *f = stbiw__fopen(filename, "wb"); 335 stbi__start_write_callbacks(s, stbi__stdio_write, (void *) f); 336 return f != NULL; 337 } 338 339 static void stbi__end_write_file(stbi__write_context *s) 340 { 341 fclose((FILE *)s->context); 342 } 343 344 #endif // !STBI_WRITE_NO_STDIO 345 346 typedef unsigned int stbiw_uint32; 347 typedef int stb_image_write_test[sizeof(stbiw_uint32)==4 ? 1 : -1]; 348 349 static void stbiw__writefv(stbi__write_context *s, const char *fmt, va_list v) 350 { 351 while (*fmt) { 352 switch (*fmt++) { 353 case ' ': break; 354 case '1': { unsigned char x = STBIW_UCHAR(va_arg(v, int)); 355 s->func(s->context,&x,1); 356 break; } 357 case '2': { int x = va_arg(v,int); 358 unsigned char b[2]; 359 b[0] = STBIW_UCHAR(x); 360 b[1] = STBIW_UCHAR(x>>8); 361 s->func(s->context,b,2); 362 break; } 363 case '4': { stbiw_uint32 x = va_arg(v,int); 364 unsigned char b[4]; 365 b[0]=STBIW_UCHAR(x); 366 b[1]=STBIW_UCHAR(x>>8); 367 b[2]=STBIW_UCHAR(x>>16); 368 b[3]=STBIW_UCHAR(x>>24); 369 s->func(s->context,b,4); 370 break; } 371 default: 372 STBIW_ASSERT(0); 373 return; 374 } 375 } 376 } 377 378 static void stbiw__writef(stbi__write_context *s, const char *fmt, ...) 379 { 380 va_list v; 381 va_start(v, fmt); 382 stbiw__writefv(s, fmt, v); 383 va_end(v); 384 } 385 386 static void stbiw__write_flush(stbi__write_context *s) 387 { 388 if (s->buf_used) { 389 s->func(s->context, &s->buffer, s->buf_used); 390 s->buf_used = 0; 391 } 392 } 393 394 static void stbiw__putc(stbi__write_context *s, unsigned char c) 395 { 396 s->func(s->context, &c, 1); 397 } 398 399 static void stbiw__write1(stbi__write_context *s, unsigned char a) 400 { 401 if ((size_t)s->buf_used + 1 > sizeof(s->buffer)) 402 stbiw__write_flush(s); 403 s->buffer[s->buf_used++] = a; 404 } 405 406 static void stbiw__write3(stbi__write_context *s, unsigned char a, unsigned char b, unsigned char c) 407 { 408 int n; 409 if ((size_t)s->buf_used + 3 > sizeof(s->buffer)) 410 stbiw__write_flush(s); 411 n = s->buf_used; 412 s->buf_used = n+3; 413 s->buffer[n+0] = a; 414 s->buffer[n+1] = b; 415 s->buffer[n+2] = c; 416 } 417 418 static void stbiw__write_pixel(stbi__write_context *s, int rgb_dir, int comp, int write_alpha, int expand_mono, unsigned char *d) 419 { 420 unsigned char bg[3] = { 255, 0, 255}, px[3]; 421 int k; 422 423 if (write_alpha < 0) 424 stbiw__write1(s, d[comp - 1]); 425 426 switch (comp) { 427 case 2: // 2 pixels = mono + alpha, alpha is written separately, so same as 1-channel case 428 case 1: 429 if (expand_mono) 430 stbiw__write3(s, d[0], d[0], d[0]); // monochrome bmp 431 else 432 stbiw__write1(s, d[0]); // monochrome TGA 433 break; 434 case 4: 435 if (!write_alpha) { 436 // composite against pink background 437 for (k = 0; k < 3; ++k) 438 px[k] = bg[k] + ((d[k] - bg[k]) * d[3]) / 255; 439 stbiw__write3(s, px[1 - rgb_dir], px[1], px[1 + rgb_dir]); 440 break; 441 } 442 /* FALLTHROUGH */ 443 case 3: 444 stbiw__write3(s, d[1 - rgb_dir], d[1], d[1 + rgb_dir]); 445 break; 446 } 447 if (write_alpha > 0) 448 stbiw__write1(s, d[comp - 1]); 449 } 450 451 static void stbiw__write_pixels(stbi__write_context *s, int rgb_dir, int vdir, int x, int y, int comp, void *data, int write_alpha, int scanline_pad, int expand_mono) 452 { 453 stbiw_uint32 zero = 0; 454 int i,j, j_end; 455 456 if (y <= 0) 457 return; 458 459 if (stbi__flip_vertically_on_write) 460 vdir *= -1; 461 462 if (vdir < 0) { 463 j_end = -1; j = y-1; 464 } else { 465 j_end = y; j = 0; 466 } 467 468 for (; j != j_end; j += vdir) { 469 for (i=0; i < x; ++i) { 470 unsigned char *d = (unsigned char *) data + (j*x+i)*comp; 471 stbiw__write_pixel(s, rgb_dir, comp, write_alpha, expand_mono, d); 472 } 473 stbiw__write_flush(s); 474 s->func(s->context, &zero, scanline_pad); 475 } 476 } 477 478 static int stbiw__outfile(stbi__write_context *s, int rgb_dir, int vdir, int x, int y, int comp, int expand_mono, void *data, int alpha, int pad, const char *fmt, ...) 479 { 480 if (y < 0 || x < 0) { 481 return 0; 482 } else { 483 va_list v; 484 va_start(v, fmt); 485 stbiw__writefv(s, fmt, v); 486 va_end(v); 487 stbiw__write_pixels(s,rgb_dir,vdir,x,y,comp,data,alpha,pad, expand_mono); 488 return 1; 489 } 490 } 491 492 static int stbi_write_bmp_core(stbi__write_context *s, int x, int y, int comp, const void *data) 493 { 494 if (comp != 4) { 495 // write RGB bitmap 496 int pad = (-x*3) & 3; 497 return stbiw__outfile(s,-1,-1,x,y,comp,1,(void *) data,0,pad, 498 "11 4 22 4" "4 44 22 444444", 499 'B', 'M', 14+40+(x*3+pad)*y, 0,0, 14+40, // file header 500 40, x,y, 1,24, 0,0,0,0,0,0); // bitmap header 501 } else { 502 // RGBA bitmaps need a v4 header 503 // use BI_BITFIELDS mode with 32bpp and alpha mask 504 // (straight BI_RGB with alpha mask doesn't work in most readers) 505 return stbiw__outfile(s,-1,-1,x,y,comp,1,(void *)data,1,0, 506 "11 4 22 4" "4 44 22 444444 4444 4 444 444 444 444", 507 'B', 'M', 14+108+x*y*4, 0, 0, 14+108, // file header 508 108, x,y, 1,32, 3,0,0,0,0,0, 0xff0000,0xff00,0xff,0xff000000u, 0, 0,0,0, 0,0,0, 0,0,0, 0,0,0); // bitmap V4 header 509 } 510 } 511 512 STBIWDEF int stbi_write_bmp_to_func(stbi_write_func *func, void *context, int x, int y, int comp, const void *data) 513 { 514 stbi__write_context s = { 0 }; 515 stbi__start_write_callbacks(&s, func, context); 516 return stbi_write_bmp_core(&s, x, y, comp, data); 517 } 518 519 #ifndef STBI_WRITE_NO_STDIO 520 STBIWDEF int stbi_write_bmp(char const *filename, int x, int y, int comp, const void *data) 521 { 522 stbi__write_context s = { 0 }; 523 if (stbi__start_write_file(&s,filename)) { 524 int r = stbi_write_bmp_core(&s, x, y, comp, data); 525 stbi__end_write_file(&s); 526 return r; 527 } else 528 return 0; 529 } 530 #endif //!STBI_WRITE_NO_STDIO 531 532 static int stbi_write_tga_core(stbi__write_context *s, int x, int y, int comp, void *data) 533 { 534 int has_alpha = (comp == 2 || comp == 4); 535 int colorbytes = has_alpha ? comp-1 : comp; 536 int format = colorbytes < 2 ? 3 : 2; // 3 color channels (RGB/RGBA) = 2, 1 color channel (Y/YA) = 3 537 538 if (y < 0 || x < 0) 539 return 0; 540 541 if (!stbi_write_tga_with_rle) { 542 return stbiw__outfile(s, -1, -1, x, y, comp, 0, (void *) data, has_alpha, 0, 543 "111 221 2222 11", 0, 0, format, 0, 0, 0, 0, 0, x, y, (colorbytes + has_alpha) * 8, has_alpha * 8); 544 } else { 545 int i,j,k; 546 int jend, jdir; 547 548 stbiw__writef(s, "111 221 2222 11", 0,0,format+8, 0,0,0, 0,0,x,y, (colorbytes + has_alpha) * 8, has_alpha * 8); 549 550 if (stbi__flip_vertically_on_write) { 551 j = 0; 552 jend = y; 553 jdir = 1; 554 } else { 555 j = y-1; 556 jend = -1; 557 jdir = -1; 558 } 559 for (; j != jend; j += jdir) { 560 unsigned char *row = (unsigned char *) data + j * x * comp; 561 int len; 562 563 for (i = 0; i < x; i += len) { 564 unsigned char *begin = row + i * comp; 565 int diff = 1; 566 len = 1; 567 568 if (i < x - 1) { 569 ++len; 570 diff = memcmp(begin, row + (i + 1) * comp, comp); 571 if (diff) { 572 const unsigned char *prev = begin; 573 for (k = i + 2; k < x && len < 128; ++k) { 574 if (memcmp(prev, row + k * comp, comp)) { 575 prev += comp; 576 ++len; 577 } else { 578 --len; 579 break; 580 } 581 } 582 } else { 583 for (k = i + 2; k < x && len < 128; ++k) { 584 if (!memcmp(begin, row + k * comp, comp)) { 585 ++len; 586 } else { 587 break; 588 } 589 } 590 } 591 } 592 593 if (diff) { 594 unsigned char header = STBIW_UCHAR(len - 1); 595 stbiw__write1(s, header); 596 for (k = 0; k < len; ++k) { 597 stbiw__write_pixel(s, -1, comp, has_alpha, 0, begin + k * comp); 598 } 599 } else { 600 unsigned char header = STBIW_UCHAR(len - 129); 601 stbiw__write1(s, header); 602 stbiw__write_pixel(s, -1, comp, has_alpha, 0, begin); 603 } 604 } 605 } 606 stbiw__write_flush(s); 607 } 608 return 1; 609 } 610 611 STBIWDEF int stbi_write_tga_to_func(stbi_write_func *func, void *context, int x, int y, int comp, const void *data) 612 { 613 stbi__write_context s = { 0 }; 614 stbi__start_write_callbacks(&s, func, context); 615 return stbi_write_tga_core(&s, x, y, comp, (void *) data); 616 } 617 618 #ifndef STBI_WRITE_NO_STDIO 619 STBIWDEF int stbi_write_tga(char const *filename, int x, int y, int comp, const void *data) 620 { 621 stbi__write_context s = { 0 }; 622 if (stbi__start_write_file(&s,filename)) { 623 int r = stbi_write_tga_core(&s, x, y, comp, (void *) data); 624 stbi__end_write_file(&s); 625 return r; 626 } else 627 return 0; 628 } 629 #endif 630 631 // ************************************************************************************************* 632 // Radiance RGBE HDR writer 633 // by Baldur Karlsson 634 635 #define stbiw__max(a, b) ((a) > (b) ? (a) : (b)) 636 637 #ifndef STBI_WRITE_NO_STDIO 638 639 static void stbiw__linear_to_rgbe(unsigned char *rgbe, float *linear) 640 { 641 int exponent; 642 float maxcomp = stbiw__max(linear[0], stbiw__max(linear[1], linear[2])); 643 644 if (maxcomp < 1e-32f) { 645 rgbe[0] = rgbe[1] = rgbe[2] = rgbe[3] = 0; 646 } else { 647 float normalize = (float) frexp(maxcomp, &exponent) * 256.0f/maxcomp; 648 649 rgbe[0] = (unsigned char)(linear[0] * normalize); 650 rgbe[1] = (unsigned char)(linear[1] * normalize); 651 rgbe[2] = (unsigned char)(linear[2] * normalize); 652 rgbe[3] = (unsigned char)(exponent + 128); 653 } 654 } 655 656 static void stbiw__write_run_data(stbi__write_context *s, int length, unsigned char databyte) 657 { 658 unsigned char lengthbyte = STBIW_UCHAR(length+128); 659 STBIW_ASSERT(length+128 <= 255); 660 s->func(s->context, &lengthbyte, 1); 661 s->func(s->context, &databyte, 1); 662 } 663 664 static void stbiw__write_dump_data(stbi__write_context *s, int length, unsigned char *data) 665 { 666 unsigned char lengthbyte = STBIW_UCHAR(length); 667 STBIW_ASSERT(length <= 128); // inconsistent with spec but consistent with official code 668 s->func(s->context, &lengthbyte, 1); 669 s->func(s->context, data, length); 670 } 671 672 static void stbiw__write_hdr_scanline(stbi__write_context *s, int width, int ncomp, unsigned char *scratch, float *scanline) 673 { 674 unsigned char scanlineheader[4] = { 2, 2, 0, 0 }; 675 unsigned char rgbe[4]; 676 float linear[3]; 677 int x; 678 679 scanlineheader[2] = (width&0xff00)>>8; 680 scanlineheader[3] = (width&0x00ff); 681 682 /* skip RLE for images too small or large */ 683 if (width < 8 || width >= 32768) { 684 for (x=0; x < width; x++) { 685 switch (ncomp) { 686 case 4: /* fallthrough */ 687 case 3: linear[2] = scanline[x*ncomp + 2]; 688 linear[1] = scanline[x*ncomp + 1]; 689 linear[0] = scanline[x*ncomp + 0]; 690 break; 691 default: 692 linear[0] = linear[1] = linear[2] = scanline[x*ncomp + 0]; 693 break; 694 } 695 stbiw__linear_to_rgbe(rgbe, linear); 696 s->func(s->context, rgbe, 4); 697 } 698 } else { 699 int c,r; 700 /* encode into scratch buffer */ 701 for (x=0; x < width; x++) { 702 switch(ncomp) { 703 case 4: /* fallthrough */ 704 case 3: linear[2] = scanline[x*ncomp + 2]; 705 linear[1] = scanline[x*ncomp + 1]; 706 linear[0] = scanline[x*ncomp + 0]; 707 break; 708 default: 709 linear[0] = linear[1] = linear[2] = scanline[x*ncomp + 0]; 710 break; 711 } 712 stbiw__linear_to_rgbe(rgbe, linear); 713 scratch[x + width*0] = rgbe[0]; 714 scratch[x + width*1] = rgbe[1]; 715 scratch[x + width*2] = rgbe[2]; 716 scratch[x + width*3] = rgbe[3]; 717 } 718 719 s->func(s->context, scanlineheader, 4); 720 721 /* RLE each component separately */ 722 for (c=0; c < 4; c++) { 723 unsigned char *comp = &scratch[width*c]; 724 725 x = 0; 726 while (x < width) { 727 // find first run 728 r = x; 729 while (r+2 < width) { 730 if (comp[r] == comp[r+1] && comp[r] == comp[r+2]) 731 break; 732 ++r; 733 } 734 if (r+2 >= width) 735 r = width; 736 // dump up to first run 737 while (x < r) { 738 int len = r-x; 739 if (len > 128) len = 128; 740 stbiw__write_dump_data(s, len, &comp[x]); 741 x += len; 742 } 743 // if there's a run, output it 744 if (r+2 < width) { // same test as what we break out of in search loop, so only true if we break'd 745 // find next byte after run 746 while (r < width && comp[r] == comp[x]) 747 ++r; 748 // output run up to r 749 while (x < r) { 750 int len = r-x; 751 if (len > 127) len = 127; 752 stbiw__write_run_data(s, len, comp[x]); 753 x += len; 754 } 755 } 756 } 757 } 758 } 759 } 760 761 static int stbi_write_hdr_core(stbi__write_context *s, int x, int y, int comp, float *data) 762 { 763 if (y <= 0 || x <= 0 || data == NULL) 764 return 0; 765 else { 766 // Each component is stored separately. Allocate scratch space for full output scanline. 767 unsigned char *scratch = (unsigned char *) STBIW_MALLOC(x*4); 768 int i, len; 769 char buffer[128]; 770 char header[] = "#?RADIANCE\n# Written by stb_image_write.h\nFORMAT=32-bit_rle_rgbe\n"; 771 s->func(s->context, header, sizeof(header)-1); 772 773 #ifdef __STDC_LIB_EXT1__ 774 len = sprintf_s(buffer, sizeof(buffer), "EXPOSURE= 1.0000000000000\n\n-Y %d +X %d\n", y, x); 775 #else 776 len = sprintf(buffer, "EXPOSURE= 1.0000000000000\n\n-Y %d +X %d\n", y, x); 777 #endif 778 s->func(s->context, buffer, len); 779 780 for(i=0; i < y; i++) 781 stbiw__write_hdr_scanline(s, x, comp, scratch, data + comp*x*(stbi__flip_vertically_on_write ? y-1-i : i)); 782 STBIW_FREE(scratch); 783 return 1; 784 } 785 } 786 787 STBIWDEF int stbi_write_hdr_to_func(stbi_write_func *func, void *context, int x, int y, int comp, const float *data) 788 { 789 stbi__write_context s = { 0 }; 790 stbi__start_write_callbacks(&s, func, context); 791 return stbi_write_hdr_core(&s, x, y, comp, (float *) data); 792 } 793 794 STBIWDEF int stbi_write_hdr(char const *filename, int x, int y, int comp, const float *data) 795 { 796 stbi__write_context s = { 0 }; 797 if (stbi__start_write_file(&s,filename)) { 798 int r = stbi_write_hdr_core(&s, x, y, comp, (float *) data); 799 stbi__end_write_file(&s); 800 return r; 801 } else 802 return 0; 803 } 804 #endif // STBI_WRITE_NO_STDIO 805 806 807 ////////////////////////////////////////////////////////////////////////////// 808 // 809 // PNG writer 810 // 811 812 #ifndef STBIW_ZLIB_COMPRESS 813 // stretchy buffer; stbiw__sbpush() == vector<>::push_back() -- stbiw__sbcount() == vector<>::size() 814 #define stbiw__sbraw(a) ((int *) (void *) (a) - 2) 815 #define stbiw__sbm(a) stbiw__sbraw(a)[0] 816 #define stbiw__sbn(a) stbiw__sbraw(a)[1] 817 818 #define stbiw__sbneedgrow(a,n) ((a)==0 || stbiw__sbn(a)+n >= stbiw__sbm(a)) 819 #define stbiw__sbmaybegrow(a,n) (stbiw__sbneedgrow(a,(n)) ? stbiw__sbgrow(a,n) : 0) 820 #define stbiw__sbgrow(a,n) stbiw__sbgrowf((void **) &(a), (n), sizeof(*(a))) 821 822 #define stbiw__sbpush(a, v) (stbiw__sbmaybegrow(a,1), (a)[stbiw__sbn(a)++] = (v)) 823 #define stbiw__sbcount(a) ((a) ? stbiw__sbn(a) : 0) 824 #define stbiw__sbfree(a) ((a) ? STBIW_FREE(stbiw__sbraw(a)),0 : 0) 825 826 static void *stbiw__sbgrowf(void **arr, int increment, int itemsize) 827 { 828 int m = *arr ? 2*stbiw__sbm(*arr)+increment : increment+1; 829 void *p = STBIW_REALLOC_SIZED(*arr ? stbiw__sbraw(*arr) : 0, *arr ? (stbiw__sbm(*arr)*itemsize + sizeof(int)*2) : 0, itemsize * m + sizeof(int)*2); 830 STBIW_ASSERT(p); 831 if (p) { 832 if (!*arr) ((int *) p)[1] = 0; 833 *arr = (void *) ((int *) p + 2); 834 stbiw__sbm(*arr) = m; 835 } 836 return *arr; 837 } 838 839 static unsigned char *stbiw__zlib_flushf(unsigned char *data, unsigned int *bitbuffer, int *bitcount) 840 { 841 while (*bitcount >= 8) { 842 stbiw__sbpush(data, STBIW_UCHAR(*bitbuffer)); 843 *bitbuffer >>= 8; 844 *bitcount -= 8; 845 } 846 return data; 847 } 848 849 static int stbiw__zlib_bitrev(int code, int codebits) 850 { 851 int res=0; 852 while (codebits--) { 853 res = (res << 1) | (code & 1); 854 code >>= 1; 855 } 856 return res; 857 } 858 859 static unsigned int stbiw__zlib_countm(unsigned char *a, unsigned char *b, int limit) 860 { 861 int i; 862 for (i=0; i < limit && i < 258; ++i) 863 if (a[i] != b[i]) break; 864 return i; 865 } 866 867 static unsigned int stbiw__zhash(unsigned char *data) 868 { 869 stbiw_uint32 hash = data[0] + (data[1] << 8) + (data[2] << 16); 870 hash ^= hash << 3; 871 hash += hash >> 5; 872 hash ^= hash << 4; 873 hash += hash >> 17; 874 hash ^= hash << 25; 875 hash += hash >> 6; 876 return hash; 877 } 878 879 #define stbiw__zlib_flush() (out = stbiw__zlib_flushf(out, &bitbuf, &bitcount)) 880 #define stbiw__zlib_add(code,codebits) \ 881 (bitbuf |= (code) << bitcount, bitcount += (codebits), stbiw__zlib_flush()) 882 #define stbiw__zlib_huffa(b,c) stbiw__zlib_add(stbiw__zlib_bitrev(b,c),c) 883 // default huffman tables 884 #define stbiw__zlib_huff1(n) stbiw__zlib_huffa(0x30 + (n), 8) 885 #define stbiw__zlib_huff2(n) stbiw__zlib_huffa(0x190 + (n)-144, 9) 886 #define stbiw__zlib_huff3(n) stbiw__zlib_huffa(0 + (n)-256,7) 887 #define stbiw__zlib_huff4(n) stbiw__zlib_huffa(0xc0 + (n)-280,8) 888 #define stbiw__zlib_huff(n) ((n) <= 143 ? stbiw__zlib_huff1(n) : (n) <= 255 ? stbiw__zlib_huff2(n) : (n) <= 279 ? stbiw__zlib_huff3(n) : stbiw__zlib_huff4(n)) 889 #define stbiw__zlib_huffb(n) ((n) <= 143 ? stbiw__zlib_huff1(n) : stbiw__zlib_huff2(n)) 890 891 #define stbiw__ZHASH 16384 892 893 #endif // STBIW_ZLIB_COMPRESS 894 895 STBIWDEF unsigned char * stbi_zlib_compress(unsigned char *data, int data_len, int *out_len, int quality) 896 { 897 #ifdef STBIW_ZLIB_COMPRESS 898 // user provided a zlib compress implementation, use that 899 return STBIW_ZLIB_COMPRESS(data, data_len, out_len, quality); 900 #else // use builtin 901 static unsigned short lengthc[] = { 3,4,5,6,7,8,9,10,11,13,15,17,19,23,27,31,35,43,51,59,67,83,99,115,131,163,195,227,258, 259 }; 902 static unsigned char lengtheb[]= { 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 }; 903 static unsigned short distc[] = { 1,2,3,4,5,7,9,13,17,25,33,49,65,97,129,193,257,385,513,769,1025,1537,2049,3073,4097,6145,8193,12289,16385,24577, 32768 }; 904 static unsigned char disteb[] = { 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 }; 905 unsigned int bitbuf=0; 906 int i,j, bitcount=0; 907 unsigned char *out = NULL; 908 unsigned char ***hash_table = (unsigned char***) STBIW_MALLOC(stbiw__ZHASH * sizeof(unsigned char**)); 909 if (hash_table == NULL) 910 return NULL; 911 if (quality < 5) quality = 5; 912 913 stbiw__sbpush(out, 0x78); // DEFLATE 32K window 914 stbiw__sbpush(out, 0x5e); // FLEVEL = 1 915 stbiw__zlib_add(1,1); // BFINAL = 1 916 stbiw__zlib_add(1,2); // BTYPE = 1 -- fixed huffman 917 918 for (i=0; i < stbiw__ZHASH; ++i) 919 hash_table[i] = NULL; 920 921 i=0; 922 while (i < data_len-3) { 923 // hash next 3 bytes of data to be compressed 924 int h = stbiw__zhash(data+i)&(stbiw__ZHASH-1), best=3; 925 unsigned char *bestloc = 0; 926 unsigned char **hlist = hash_table[h]; 927 int n = stbiw__sbcount(hlist); 928 for (j=0; j < n; ++j) { 929 if (hlist[j]-data > i-32768) { // if entry lies within window 930 int d = stbiw__zlib_countm(hlist[j], data+i, data_len-i); 931 if (d >= best) { best=d; bestloc=hlist[j]; } 932 } 933 } 934 // when hash table entry is too long, delete half the entries 935 if (hash_table[h] && stbiw__sbn(hash_table[h]) == 2*quality) { 936 STBIW_MEMMOVE(hash_table[h], hash_table[h]+quality, sizeof(hash_table[h][0])*quality); 937 stbiw__sbn(hash_table[h]) = quality; 938 } 939 stbiw__sbpush(hash_table[h],data+i); 940 941 if (bestloc) { 942 // "lazy matching" - check match at *next* byte, and if it's better, do cur byte as literal 943 h = stbiw__zhash(data+i+1)&(stbiw__ZHASH-1); 944 hlist = hash_table[h]; 945 n = stbiw__sbcount(hlist); 946 for (j=0; j < n; ++j) { 947 if (hlist[j]-data > i-32767) { 948 int e = stbiw__zlib_countm(hlist[j], data+i+1, data_len-i-1); 949 if (e > best) { // if next match is better, bail on current match 950 bestloc = NULL; 951 break; 952 } 953 } 954 } 955 } 956 957 if (bestloc) { 958 int d = (int) (data+i - bestloc); // distance back 959 STBIW_ASSERT(d <= 32767 && best <= 258); 960 for (j=0; best > lengthc[j+1]-1; ++j); 961 stbiw__zlib_huff(j+257); 962 if (lengtheb[j]) stbiw__zlib_add(best - lengthc[j], lengtheb[j]); 963 for (j=0; d > distc[j+1]-1; ++j); 964 stbiw__zlib_add(stbiw__zlib_bitrev(j,5),5); 965 if (disteb[j]) stbiw__zlib_add(d - distc[j], disteb[j]); 966 i += best; 967 } else { 968 stbiw__zlib_huffb(data[i]); 969 ++i; 970 } 971 } 972 // write out final bytes 973 for (;i < data_len; ++i) 974 stbiw__zlib_huffb(data[i]); 975 stbiw__zlib_huff(256); // end of block 976 // pad with 0 bits to byte boundary 977 while (bitcount) 978 stbiw__zlib_add(0,1); 979 980 for (i=0; i < stbiw__ZHASH; ++i) 981 (void) stbiw__sbfree(hash_table[i]); 982 STBIW_FREE(hash_table); 983 984 // store uncompressed instead if compression was worse 985 if (stbiw__sbn(out) > data_len + 2 + ((data_len+32766)/32767)*5) { 986 stbiw__sbn(out) = 2; // truncate to DEFLATE 32K window and FLEVEL = 1 987 for (j = 0; j < data_len;) { 988 int blocklen = data_len - j; 989 if (blocklen > 32767) blocklen = 32767; 990 stbiw__sbpush(out, data_len - j == blocklen); // BFINAL = ?, BTYPE = 0 -- no compression 991 stbiw__sbpush(out, STBIW_UCHAR(blocklen)); // LEN 992 stbiw__sbpush(out, STBIW_UCHAR(blocklen >> 8)); 993 stbiw__sbpush(out, STBIW_UCHAR(~blocklen)); // NLEN 994 stbiw__sbpush(out, STBIW_UCHAR(~blocklen >> 8)); 995 memcpy(out+stbiw__sbn(out), data+j, blocklen); 996 stbiw__sbn(out) += blocklen; 997 j += blocklen; 998 } 999 } 1000 1001 { 1002 // compute adler32 on input 1003 unsigned int s1=1, s2=0; 1004 int blocklen = (int) (data_len % 5552); 1005 j=0; 1006 while (j < data_len) { 1007 for (i=0; i < blocklen; ++i) { s1 += data[j+i]; s2 += s1; } 1008 s1 %= 65521; s2 %= 65521; 1009 j += blocklen; 1010 blocklen = 5552; 1011 } 1012 stbiw__sbpush(out, STBIW_UCHAR(s2 >> 8)); 1013 stbiw__sbpush(out, STBIW_UCHAR(s2)); 1014 stbiw__sbpush(out, STBIW_UCHAR(s1 >> 8)); 1015 stbiw__sbpush(out, STBIW_UCHAR(s1)); 1016 } 1017 *out_len = stbiw__sbn(out); 1018 // make returned pointer freeable 1019 STBIW_MEMMOVE(stbiw__sbraw(out), out, *out_len); 1020 return (unsigned char *) stbiw__sbraw(out); 1021 #endif // STBIW_ZLIB_COMPRESS 1022 } 1023 1024 static unsigned int stbiw__crc32(unsigned char *buffer, int len) 1025 { 1026 #ifdef STBIW_CRC32 1027 return STBIW_CRC32(buffer, len); 1028 #else 1029 static unsigned int crc_table[256] = 1030 { 1031 0x00000000, 0x77073096, 0xEE0E612C, 0x990951BA, 0x076DC419, 0x706AF48F, 0xE963A535, 0x9E6495A3, 1032 0x0eDB8832, 0x79DCB8A4, 0xE0D5E91E, 0x97D2D988, 0x09B64C2B, 0x7EB17CBD, 0xE7B82D07, 0x90BF1D91, 1033 0x1DB71064, 0x6AB020F2, 0xF3B97148, 0x84BE41DE, 0x1ADAD47D, 0x6DDDE4EB, 0xF4D4B551, 0x83D385C7, 1034 0x136C9856, 0x646BA8C0, 0xFD62F97A, 0x8A65C9EC, 0x14015C4F, 0x63066CD9, 0xFA0F3D63, 0x8D080DF5, 1035 0x3B6E20C8, 0x4C69105E, 0xD56041E4, 0xA2677172, 0x3C03E4D1, 0x4B04D447, 0xD20D85FD, 0xA50AB56B, 1036 0x35B5A8FA, 0x42B2986C, 0xDBBBC9D6, 0xACBCF940, 0x32D86CE3, 0x45DF5C75, 0xDCD60DCF, 0xABD13D59, 1037 0x26D930AC, 0x51DE003A, 0xC8D75180, 0xBFD06116, 0x21B4F4B5, 0x56B3C423, 0xCFBA9599, 0xB8BDA50F, 1038 0x2802B89E, 0x5F058808, 0xC60CD9B2, 0xB10BE924, 0x2F6F7C87, 0x58684C11, 0xC1611DAB, 0xB6662D3D, 1039 0x76DC4190, 0x01DB7106, 0x98D220BC, 0xEFD5102A, 0x71B18589, 0x06B6B51F, 0x9FBFE4A5, 0xE8B8D433, 1040 0x7807C9A2, 0x0F00F934, 0x9609A88E, 0xE10E9818, 0x7F6A0DBB, 0x086D3D2D, 0x91646C97, 0xE6635C01, 1041 0x6B6B51F4, 0x1C6C6162, 0x856530D8, 0xF262004E, 0x6C0695ED, 0x1B01A57B, 0x8208F4C1, 0xF50FC457, 1042 0x65B0D9C6, 0x12B7E950, 0x8BBEB8EA, 0xFCB9887C, 0x62DD1DDF, 0x15DA2D49, 0x8CD37CF3, 0xFBD44C65, 1043 0x4DB26158, 0x3AB551CE, 0xA3BC0074, 0xD4BB30E2, 0x4ADFA541, 0x3DD895D7, 0xA4D1C46D, 0xD3D6F4FB, 1044 0x4369E96A, 0x346ED9FC, 0xAD678846, 0xDA60B8D0, 0x44042D73, 0x33031DE5, 0xAA0A4C5F, 0xDD0D7CC9, 1045 0x5005713C, 0x270241AA, 0xBE0B1010, 0xC90C2086, 0x5768B525, 0x206F85B3, 0xB966D409, 0xCE61E49F, 1046 0x5EDEF90E, 0x29D9C998, 0xB0D09822, 0xC7D7A8B4, 0x59B33D17, 0x2EB40D81, 0xB7BD5C3B, 0xC0BA6CAD, 1047 0xEDB88320, 0x9ABFB3B6, 0x03B6E20C, 0x74B1D29A, 0xEAD54739, 0x9DD277AF, 0x04DB2615, 0x73DC1683, 1048 0xE3630B12, 0x94643B84, 0x0D6D6A3E, 0x7A6A5AA8, 0xE40ECF0B, 0x9309FF9D, 0x0A00AE27, 0x7D079EB1, 1049 0xF00F9344, 0x8708A3D2, 0x1E01F268, 0x6906C2FE, 0xF762575D, 0x806567CB, 0x196C3671, 0x6E6B06E7, 1050 0xFED41B76, 0x89D32BE0, 0x10DA7A5A, 0x67DD4ACC, 0xF9B9DF6F, 0x8EBEEFF9, 0x17B7BE43, 0x60B08ED5, 1051 0xD6D6A3E8, 0xA1D1937E, 0x38D8C2C4, 0x4FDFF252, 0xD1BB67F1, 0xA6BC5767, 0x3FB506DD, 0x48B2364B, 1052 0xD80D2BDA, 0xAF0A1B4C, 0x36034AF6, 0x41047A60, 0xDF60EFC3, 0xA867DF55, 0x316E8EEF, 0x4669BE79, 1053 0xCB61B38C, 0xBC66831A, 0x256FD2A0, 0x5268E236, 0xCC0C7795, 0xBB0B4703, 0x220216B9, 0x5505262F, 1054 0xC5BA3BBE, 0xB2BD0B28, 0x2BB45A92, 0x5CB36A04, 0xC2D7FFA7, 0xB5D0CF31, 0x2CD99E8B, 0x5BDEAE1D, 1055 0x9B64C2B0, 0xEC63F226, 0x756AA39C, 0x026D930A, 0x9C0906A9, 0xEB0E363F, 0x72076785, 0x05005713, 1056 0x95BF4A82, 0xE2B87A14, 0x7BB12BAE, 0x0CB61B38, 0x92D28E9B, 0xE5D5BE0D, 0x7CDCEFB7, 0x0BDBDF21, 1057 0x86D3D2D4, 0xF1D4E242, 0x68DDB3F8, 0x1FDA836E, 0x81BE16CD, 0xF6B9265B, 0x6FB077E1, 0x18B74777, 1058 0x88085AE6, 0xFF0F6A70, 0x66063BCA, 0x11010B5C, 0x8F659EFF, 0xF862AE69, 0x616BFFD3, 0x166CCF45, 1059 0xA00AE278, 0xD70DD2EE, 0x4E048354, 0x3903B3C2, 0xA7672661, 0xD06016F7, 0x4969474D, 0x3E6E77DB, 1060 0xAED16A4A, 0xD9D65ADC, 0x40DF0B66, 0x37D83BF0, 0xA9BCAE53, 0xDEBB9EC5, 0x47B2CF7F, 0x30B5FFE9, 1061 0xBDBDF21C, 0xCABAC28A, 0x53B39330, 0x24B4A3A6, 0xBAD03605, 0xCDD70693, 0x54DE5729, 0x23D967BF, 1062 0xB3667A2E, 0xC4614AB8, 0x5D681B02, 0x2A6F2B94, 0xB40BBE37, 0xC30C8EA1, 0x5A05DF1B, 0x2D02EF8D 1063 }; 1064 1065 unsigned int crc = ~0u; 1066 int i; 1067 for (i=0; i < len; ++i) 1068 crc = (crc >> 8) ^ crc_table[buffer[i] ^ (crc & 0xff)]; 1069 return ~crc; 1070 #endif 1071 } 1072 1073 #define stbiw__wpng4(o,a,b,c,d) ((o)[0]=STBIW_UCHAR(a),(o)[1]=STBIW_UCHAR(b),(o)[2]=STBIW_UCHAR(c),(o)[3]=STBIW_UCHAR(d),(o)+=4) 1074 #define stbiw__wp32(data,v) stbiw__wpng4(data, (v)>>24,(v)>>16,(v)>>8,(v)); 1075 #define stbiw__wptag(data,s) stbiw__wpng4(data, s[0],s[1],s[2],s[3]) 1076 1077 static void stbiw__wpcrc(unsigned char **data, int len) 1078 { 1079 unsigned int crc = stbiw__crc32(*data - len - 4, len+4); 1080 stbiw__wp32(*data, crc); 1081 } 1082 1083 static unsigned char stbiw__paeth(int a, int b, int c) 1084 { 1085 int p = a + b - c, pa = abs(p-a), pb = abs(p-b), pc = abs(p-c); 1086 if (pa <= pb && pa <= pc) return STBIW_UCHAR(a); 1087 if (pb <= pc) return STBIW_UCHAR(b); 1088 return STBIW_UCHAR(c); 1089 } 1090 1091 // @OPTIMIZE: provide an option that always forces left-predict or paeth predict 1092 static void stbiw__encode_png_line(unsigned char *pixels, int stride_bytes, int width, int height, int y, int n, int filter_type, signed char *line_buffer) 1093 { 1094 static int mapping[] = { 0,1,2,3,4 }; 1095 static int firstmap[] = { 0,1,0,5,6 }; 1096 int *mymap = (y != 0) ? mapping : firstmap; 1097 int i; 1098 int type = mymap[filter_type]; 1099 unsigned char *z = pixels + stride_bytes * (stbi__flip_vertically_on_write ? height-1-y : y); 1100 int signed_stride = stbi__flip_vertically_on_write ? -stride_bytes : stride_bytes; 1101 1102 if (type==0) { 1103 memcpy(line_buffer, z, width*n); 1104 return; 1105 } 1106 1107 // first loop isn't optimized since it's just one pixel 1108 for (i = 0; i < n; ++i) { 1109 switch (type) { 1110 case 1: line_buffer[i] = z[i]; break; 1111 case 2: line_buffer[i] = z[i] - z[i-signed_stride]; break; 1112 case 3: line_buffer[i] = z[i] - (z[i-signed_stride]>>1); break; 1113 case 4: line_buffer[i] = (signed char) (z[i] - stbiw__paeth(0,z[i-signed_stride],0)); break; 1114 case 5: line_buffer[i] = z[i]; break; 1115 case 6: line_buffer[i] = z[i]; break; 1116 } 1117 } 1118 switch (type) { 1119 case 1: for (i=n; i < width*n; ++i) line_buffer[i] = z[i] - z[i-n]; break; 1120 case 2: for (i=n; i < width*n; ++i) line_buffer[i] = z[i] - z[i-signed_stride]; break; 1121 case 3: for (i=n; i < width*n; ++i) line_buffer[i] = z[i] - ((z[i-n] + z[i-signed_stride])>>1); break; 1122 case 4: for (i=n; i < width*n; ++i) line_buffer[i] = z[i] - stbiw__paeth(z[i-n], z[i-signed_stride], z[i-signed_stride-n]); break; 1123 case 5: for (i=n; i < width*n; ++i) line_buffer[i] = z[i] - (z[i-n]>>1); break; 1124 case 6: for (i=n; i < width*n; ++i) line_buffer[i] = z[i] - stbiw__paeth(z[i-n], 0,0); break; 1125 } 1126 } 1127 1128 STBIWDEF unsigned char *stbi_write_png_to_mem(const unsigned char *pixels, int stride_bytes, int x, int y, int n, int *out_len) 1129 { 1130 int force_filter = stbi_write_force_png_filter; 1131 int ctype[5] = { -1, 0, 4, 2, 6 }; 1132 unsigned char sig[8] = { 137,80,78,71,13,10,26,10 }; 1133 unsigned char *out,*o, *filt, *zlib; 1134 signed char *line_buffer; 1135 int j,zlen; 1136 1137 if (stride_bytes == 0) 1138 stride_bytes = x * n; 1139 1140 if (force_filter >= 5) { 1141 force_filter = -1; 1142 } 1143 1144 filt = (unsigned char *) STBIW_MALLOC((x*n+1) * y); if (!filt) return 0; 1145 line_buffer = (signed char *) STBIW_MALLOC(x * n); if (!line_buffer) { STBIW_FREE(filt); return 0; } 1146 for (j=0; j < y; ++j) { 1147 int filter_type; 1148 if (force_filter > -1) { 1149 filter_type = force_filter; 1150 stbiw__encode_png_line((unsigned char*)(pixels), stride_bytes, x, y, j, n, force_filter, line_buffer); 1151 } else { // Estimate the best filter by running through all of them: 1152 int best_filter = 0, best_filter_val = 0x7fffffff, est, i; 1153 for (filter_type = 0; filter_type < 5; filter_type++) { 1154 stbiw__encode_png_line((unsigned char*)(pixels), stride_bytes, x, y, j, n, filter_type, line_buffer); 1155 1156 // Estimate the entropy of the line using this filter; the less, the better. 1157 est = 0; 1158 for (i = 0; i < x*n; ++i) { 1159 est += abs((signed char) line_buffer[i]); 1160 } 1161 if (est < best_filter_val) { 1162 best_filter_val = est; 1163 best_filter = filter_type; 1164 } 1165 } 1166 if (filter_type != best_filter) { // If the last iteration already got us the best filter, don't redo it 1167 stbiw__encode_png_line((unsigned char*)(pixels), stride_bytes, x, y, j, n, best_filter, line_buffer); 1168 filter_type = best_filter; 1169 } 1170 } 1171 // when we get here, filter_type contains the filter type, and line_buffer contains the data 1172 filt[j*(x*n+1)] = (unsigned char) filter_type; 1173 STBIW_MEMMOVE(filt+j*(x*n+1)+1, line_buffer, x*n); 1174 } 1175 STBIW_FREE(line_buffer); 1176 zlib = stbi_zlib_compress(filt, y*( x*n+1), &zlen, stbi_write_png_compression_level); 1177 STBIW_FREE(filt); 1178 if (!zlib) return 0; 1179 1180 // each tag requires 12 bytes of overhead 1181 out = (unsigned char *) STBIW_MALLOC(8 + 12+13 + 12+zlen + 12); 1182 if (!out) return 0; 1183 *out_len = 8 + 12+13 + 12+zlen + 12; 1184 1185 o=out; 1186 STBIW_MEMMOVE(o,sig,8); o+= 8; 1187 stbiw__wp32(o, 13); // header length 1188 stbiw__wptag(o, "IHDR"); 1189 stbiw__wp32(o, x); 1190 stbiw__wp32(o, y); 1191 *o++ = 8; 1192 *o++ = STBIW_UCHAR(ctype[n]); 1193 *o++ = 0; 1194 *o++ = 0; 1195 *o++ = 0; 1196 stbiw__wpcrc(&o,13); 1197 1198 stbiw__wp32(o, zlen); 1199 stbiw__wptag(o, "IDAT"); 1200 STBIW_MEMMOVE(o, zlib, zlen); 1201 o += zlen; 1202 STBIW_FREE(zlib); 1203 stbiw__wpcrc(&o, zlen); 1204 1205 stbiw__wp32(o,0); 1206 stbiw__wptag(o, "IEND"); 1207 stbiw__wpcrc(&o,0); 1208 1209 STBIW_ASSERT(o == out + *out_len); 1210 1211 return out; 1212 } 1213 1214 #ifndef STBI_WRITE_NO_STDIO 1215 STBIWDEF int stbi_write_png(char const *filename, int x, int y, int comp, const void *data, int stride_bytes) 1216 { 1217 FILE *f; 1218 int len; 1219 unsigned char *png = stbi_write_png_to_mem((const unsigned char *) data, stride_bytes, x, y, comp, &len); 1220 if (png == NULL) return 0; 1221 1222 f = stbiw__fopen(filename, "wb"); 1223 if (!f) { STBIW_FREE(png); return 0; } 1224 fwrite(png, 1, len, f); 1225 fclose(f); 1226 STBIW_FREE(png); 1227 return 1; 1228 } 1229 #endif 1230 1231 STBIWDEF int stbi_write_png_to_func(stbi_write_func *func, void *context, int x, int y, int comp, const void *data, int stride_bytes) 1232 { 1233 int len; 1234 unsigned char *png = stbi_write_png_to_mem((const unsigned char *) data, stride_bytes, x, y, comp, &len); 1235 if (png == NULL) return 0; 1236 func(context, png, len); 1237 STBIW_FREE(png); 1238 return 1; 1239 } 1240 1241 1242 /* *************************************************************************** 1243 * 1244 * JPEG writer 1245 * 1246 * This is based on Jon Olick's jo_jpeg.cpp: 1247 * public domain Simple, Minimalistic JPEG writer - http://www.jonolick.com/code.html 1248 */ 1249 1250 static const unsigned char stbiw__jpg_ZigZag[] = { 0,1,5,6,14,15,27,28,2,4,7,13,16,26,29,42,3,8,12,17,25,30,41,43,9,11,18, 1251 24,31,40,44,53,10,19,23,32,39,45,52,54,20,22,33,38,46,51,55,60,21,34,37,47,50,56,59,61,35,36,48,49,57,58,62,63 }; 1252 1253 static void stbiw__jpg_writeBits(stbi__write_context *s, int *bitBufP, int *bitCntP, const unsigned short *bs) { 1254 int bitBuf = *bitBufP, bitCnt = *bitCntP; 1255 bitCnt += bs[1]; 1256 bitBuf |= bs[0] << (24 - bitCnt); 1257 while(bitCnt >= 8) { 1258 unsigned char c = (bitBuf >> 16) & 255; 1259 stbiw__putc(s, c); 1260 if(c == 255) { 1261 stbiw__putc(s, 0); 1262 } 1263 bitBuf <<= 8; 1264 bitCnt -= 8; 1265 } 1266 *bitBufP = bitBuf; 1267 *bitCntP = bitCnt; 1268 } 1269 1270 static void stbiw__jpg_DCT(float *d0p, float *d1p, float *d2p, float *d3p, float *d4p, float *d5p, float *d6p, float *d7p) { 1271 float d0 = *d0p, d1 = *d1p, d2 = *d2p, d3 = *d3p, d4 = *d4p, d5 = *d5p, d6 = *d6p, d7 = *d7p; 1272 float z1, z2, z3, z4, z5, z11, z13; 1273 1274 float tmp0 = d0 + d7; 1275 float tmp7 = d0 - d7; 1276 float tmp1 = d1 + d6; 1277 float tmp6 = d1 - d6; 1278 float tmp2 = d2 + d5; 1279 float tmp5 = d2 - d5; 1280 float tmp3 = d3 + d4; 1281 float tmp4 = d3 - d4; 1282 1283 // Even part 1284 float tmp10 = tmp0 + tmp3; // phase 2 1285 float tmp13 = tmp0 - tmp3; 1286 float tmp11 = tmp1 + tmp2; 1287 float tmp12 = tmp1 - tmp2; 1288 1289 d0 = tmp10 + tmp11; // phase 3 1290 d4 = tmp10 - tmp11; 1291 1292 z1 = (tmp12 + tmp13) * 0.707106781f; // c4 1293 d2 = tmp13 + z1; // phase 5 1294 d6 = tmp13 - z1; 1295 1296 // Odd part 1297 tmp10 = tmp4 + tmp5; // phase 2 1298 tmp11 = tmp5 + tmp6; 1299 tmp12 = tmp6 + tmp7; 1300 1301 // The rotator is modified from fig 4-8 to avoid extra negations. 1302 z5 = (tmp10 - tmp12) * 0.382683433f; // c6 1303 z2 = tmp10 * 0.541196100f + z5; // c2-c6 1304 z4 = tmp12 * 1.306562965f + z5; // c2+c6 1305 z3 = tmp11 * 0.707106781f; // c4 1306 1307 z11 = tmp7 + z3; // phase 5 1308 z13 = tmp7 - z3; 1309 1310 *d5p = z13 + z2; // phase 6 1311 *d3p = z13 - z2; 1312 *d1p = z11 + z4; 1313 *d7p = z11 - z4; 1314 1315 *d0p = d0; *d2p = d2; *d4p = d4; *d6p = d6; 1316 } 1317 1318 static void stbiw__jpg_calcBits(int val, unsigned short bits[2]) { 1319 int tmp1 = val < 0 ? -val : val; 1320 val = val < 0 ? val-1 : val; 1321 bits[1] = 1; 1322 while(tmp1 >>= 1) { 1323 ++bits[1]; 1324 } 1325 bits[0] = val & ((1<<bits[1])-1); 1326 } 1327 1328 static int stbiw__jpg_processDU(stbi__write_context *s, int *bitBuf, int *bitCnt, float *CDU, int du_stride, float *fdtbl, int DC, const unsigned short HTDC[256][2], const unsigned short HTAC[256][2]) { 1329 const unsigned short EOB[2] = { HTAC[0x00][0], HTAC[0x00][1] }; 1330 const unsigned short M16zeroes[2] = { HTAC[0xF0][0], HTAC[0xF0][1] }; 1331 int dataOff, i, j, n, diff, end0pos, x, y; 1332 int DU[64]; 1333 1334 // DCT rows 1335 for(dataOff=0, n=du_stride*8; dataOff<n; dataOff+=du_stride) { 1336 stbiw__jpg_DCT(&CDU[dataOff], &CDU[dataOff+1], &CDU[dataOff+2], &CDU[dataOff+3], &CDU[dataOff+4], &CDU[dataOff+5], &CDU[dataOff+6], &CDU[dataOff+7]); 1337 } 1338 // DCT columns 1339 for(dataOff=0; dataOff<8; ++dataOff) { 1340 stbiw__jpg_DCT(&CDU[dataOff], &CDU[dataOff+du_stride], &CDU[dataOff+du_stride*2], &CDU[dataOff+du_stride*3], &CDU[dataOff+du_stride*4], 1341 &CDU[dataOff+du_stride*5], &CDU[dataOff+du_stride*6], &CDU[dataOff+du_stride*7]); 1342 } 1343 // Quantize/descale/zigzag the coefficients 1344 for(y = 0, j=0; y < 8; ++y) { 1345 for(x = 0; x < 8; ++x,++j) { 1346 float v; 1347 i = y*du_stride+x; 1348 v = CDU[i]*fdtbl[j]; 1349 // DU[stbiw__jpg_ZigZag[j]] = (int)(v < 0 ? ceilf(v - 0.5f) : floorf(v + 0.5f)); 1350 // ceilf() and floorf() are C99, not C89, but I /think/ they're not needed here anyway? 1351 DU[stbiw__jpg_ZigZag[j]] = (int)(v < 0 ? v - 0.5f : v + 0.5f); 1352 } 1353 } 1354 1355 // Encode DC 1356 diff = DU[0] - DC; 1357 if (diff == 0) { 1358 stbiw__jpg_writeBits(s, bitBuf, bitCnt, HTDC[0]); 1359 } else { 1360 unsigned short bits[2]; 1361 stbiw__jpg_calcBits(diff, bits); 1362 stbiw__jpg_writeBits(s, bitBuf, bitCnt, HTDC[bits[1]]); 1363 stbiw__jpg_writeBits(s, bitBuf, bitCnt, bits); 1364 } 1365 // Encode ACs 1366 end0pos = 63; 1367 for(; (end0pos>0)&&(DU[end0pos]==0); --end0pos) { 1368 } 1369 // end0pos = first element in reverse order !=0 1370 if(end0pos == 0) { 1371 stbiw__jpg_writeBits(s, bitBuf, bitCnt, EOB); 1372 return DU[0]; 1373 } 1374 for(i = 1; i <= end0pos; ++i) { 1375 int startpos = i; 1376 int nrzeroes; 1377 unsigned short bits[2]; 1378 for (; DU[i]==0 && i<=end0pos; ++i) { 1379 } 1380 nrzeroes = i-startpos; 1381 if ( nrzeroes >= 16 ) { 1382 int lng = nrzeroes>>4; 1383 int nrmarker; 1384 for (nrmarker=1; nrmarker <= lng; ++nrmarker) 1385 stbiw__jpg_writeBits(s, bitBuf, bitCnt, M16zeroes); 1386 nrzeroes &= 15; 1387 } 1388 stbiw__jpg_calcBits(DU[i], bits); 1389 stbiw__jpg_writeBits(s, bitBuf, bitCnt, HTAC[(nrzeroes<<4)+bits[1]]); 1390 stbiw__jpg_writeBits(s, bitBuf, bitCnt, bits); 1391 } 1392 if(end0pos != 63) { 1393 stbiw__jpg_writeBits(s, bitBuf, bitCnt, EOB); 1394 } 1395 return DU[0]; 1396 } 1397 1398 static int stbi_write_jpg_core(stbi__write_context *s, int width, int height, int comp, const void* data, int quality) { 1399 // Constants that don't pollute global namespace 1400 static const unsigned char std_dc_luminance_nrcodes[] = {0,0,1,5,1,1,1,1,1,1,0,0,0,0,0,0,0}; 1401 static const unsigned char std_dc_luminance_values[] = {0,1,2,3,4,5,6,7,8,9,10,11}; 1402 static const unsigned char std_ac_luminance_nrcodes[] = {0,0,2,1,3,3,2,4,3,5,5,4,4,0,0,1,0x7d}; 1403 static const unsigned char std_ac_luminance_values[] = { 1404 0x01,0x02,0x03,0x00,0x04,0x11,0x05,0x12,0x21,0x31,0x41,0x06,0x13,0x51,0x61,0x07,0x22,0x71,0x14,0x32,0x81,0x91,0xa1,0x08, 1405 0x23,0x42,0xb1,0xc1,0x15,0x52,0xd1,0xf0,0x24,0x33,0x62,0x72,0x82,0x09,0x0a,0x16,0x17,0x18,0x19,0x1a,0x25,0x26,0x27,0x28, 1406 0x29,0x2a,0x34,0x35,0x36,0x37,0x38,0x39,0x3a,0x43,0x44,0x45,0x46,0x47,0x48,0x49,0x4a,0x53,0x54,0x55,0x56,0x57,0x58,0x59, 1407 0x5a,0x63,0x64,0x65,0x66,0x67,0x68,0x69,0x6a,0x73,0x74,0x75,0x76,0x77,0x78,0x79,0x7a,0x83,0x84,0x85,0x86,0x87,0x88,0x89, 1408 0x8a,0x92,0x93,0x94,0x95,0x96,0x97,0x98,0x99,0x9a,0xa2,0xa3,0xa4,0xa5,0xa6,0xa7,0xa8,0xa9,0xaa,0xb2,0xb3,0xb4,0xb5,0xb6, 1409 0xb7,0xb8,0xb9,0xba,0xc2,0xc3,0xc4,0xc5,0xc6,0xc7,0xc8,0xc9,0xca,0xd2,0xd3,0xd4,0xd5,0xd6,0xd7,0xd8,0xd9,0xda,0xe1,0xe2, 1410 0xe3,0xe4,0xe5,0xe6,0xe7,0xe8,0xe9,0xea,0xf1,0xf2,0xf3,0xf4,0xf5,0xf6,0xf7,0xf8,0xf9,0xfa 1411 }; 1412 static const unsigned char std_dc_chrominance_nrcodes[] = {0,0,3,1,1,1,1,1,1,1,1,1,0,0,0,0,0}; 1413 static const unsigned char std_dc_chrominance_values[] = {0,1,2,3,4,5,6,7,8,9,10,11}; 1414 static const unsigned char std_ac_chrominance_nrcodes[] = {0,0,2,1,2,4,4,3,4,7,5,4,4,0,1,2,0x77}; 1415 static const unsigned char std_ac_chrominance_values[] = { 1416 0x00,0x01,0x02,0x03,0x11,0x04,0x05,0x21,0x31,0x06,0x12,0x41,0x51,0x07,0x61,0x71,0x13,0x22,0x32,0x81,0x08,0x14,0x42,0x91, 1417 0xa1,0xb1,0xc1,0x09,0x23,0x33,0x52,0xf0,0x15,0x62,0x72,0xd1,0x0a,0x16,0x24,0x34,0xe1,0x25,0xf1,0x17,0x18,0x19,0x1a,0x26, 1418 0x27,0x28,0x29,0x2a,0x35,0x36,0x37,0x38,0x39,0x3a,0x43,0x44,0x45,0x46,0x47,0x48,0x49,0x4a,0x53,0x54,0x55,0x56,0x57,0x58, 1419 0x59,0x5a,0x63,0x64,0x65,0x66,0x67,0x68,0x69,0x6a,0x73,0x74,0x75,0x76,0x77,0x78,0x79,0x7a,0x82,0x83,0x84,0x85,0x86,0x87, 1420 0x88,0x89,0x8a,0x92,0x93,0x94,0x95,0x96,0x97,0x98,0x99,0x9a,0xa2,0xa3,0xa4,0xa5,0xa6,0xa7,0xa8,0xa9,0xaa,0xb2,0xb3,0xb4, 1421 0xb5,0xb6,0xb7,0xb8,0xb9,0xba,0xc2,0xc3,0xc4,0xc5,0xc6,0xc7,0xc8,0xc9,0xca,0xd2,0xd3,0xd4,0xd5,0xd6,0xd7,0xd8,0xd9,0xda, 1422 0xe2,0xe3,0xe4,0xe5,0xe6,0xe7,0xe8,0xe9,0xea,0xf2,0xf3,0xf4,0xf5,0xf6,0xf7,0xf8,0xf9,0xfa 1423 }; 1424 // Huffman tables 1425 static const unsigned short YDC_HT[256][2] = { {0,2},{2,3},{3,3},{4,3},{5,3},{6,3},{14,4},{30,5},{62,6},{126,7},{254,8},{510,9}}; 1426 static const unsigned short UVDC_HT[256][2] = { {0,2},{1,2},{2,2},{6,3},{14,4},{30,5},{62,6},{126,7},{254,8},{510,9},{1022,10},{2046,11}}; 1427 static const unsigned short YAC_HT[256][2] = { 1428 {10,4},{0,2},{1,2},{4,3},{11,4},{26,5},{120,7},{248,8},{1014,10},{65410,16},{65411,16},{0,0},{0,0},{0,0},{0,0},{0,0},{0,0}, 1429 {12,4},{27,5},{121,7},{502,9},{2038,11},{65412,16},{65413,16},{65414,16},{65415,16},{65416,16},{0,0},{0,0},{0,0},{0,0},{0,0},{0,0}, 1430 {28,5},{249,8},{1015,10},{4084,12},{65417,16},{65418,16},{65419,16},{65420,16},{65421,16},{65422,16},{0,0},{0,0},{0,0},{0,0},{0,0},{0,0}, 1431 {58,6},{503,9},{4085,12},{65423,16},{65424,16},{65425,16},{65426,16},{65427,16},{65428,16},{65429,16},{0,0},{0,0},{0,0},{0,0},{0,0},{0,0}, 1432 {59,6},{1016,10},{65430,16},{65431,16},{65432,16},{65433,16},{65434,16},{65435,16},{65436,16},{65437,16},{0,0},{0,0},{0,0},{0,0},{0,0},{0,0}, 1433 {122,7},{2039,11},{65438,16},{65439,16},{65440,16},{65441,16},{65442,16},{65443,16},{65444,16},{65445,16},{0,0},{0,0},{0,0},{0,0},{0,0},{0,0}, 1434 {123,7},{4086,12},{65446,16},{65447,16},{65448,16},{65449,16},{65450,16},{65451,16},{65452,16},{65453,16},{0,0},{0,0},{0,0},{0,0},{0,0},{0,0}, 1435 {250,8},{4087,12},{65454,16},{65455,16},{65456,16},{65457,16},{65458,16},{65459,16},{65460,16},{65461,16},{0,0},{0,0},{0,0},{0,0},{0,0},{0,0}, 1436 {504,9},{32704,15},{65462,16},{65463,16},{65464,16},{65465,16},{65466,16},{65467,16},{65468,16},{65469,16},{0,0},{0,0},{0,0},{0,0},{0,0},{0,0}, 1437 {505,9},{65470,16},{65471,16},{65472,16},{65473,16},{65474,16},{65475,16},{65476,16},{65477,16},{65478,16},{0,0},{0,0},{0,0},{0,0},{0,0},{0,0}, 1438 {506,9},{65479,16},{65480,16},{65481,16},{65482,16},{65483,16},{65484,16},{65485,16},{65486,16},{65487,16},{0,0},{0,0},{0,0},{0,0},{0,0},{0,0}, 1439 {1017,10},{65488,16},{65489,16},{65490,16},{65491,16},{65492,16},{65493,16},{65494,16},{65495,16},{65496,16},{0,0},{0,0},{0,0},{0,0},{0,0},{0,0}, 1440 {1018,10},{65497,16},{65498,16},{65499,16},{65500,16},{65501,16},{65502,16},{65503,16},{65504,16},{65505,16},{0,0},{0,0},{0,0},{0,0},{0,0},{0,0}, 1441 {2040,11},{65506,16},{65507,16},{65508,16},{65509,16},{65510,16},{65511,16},{65512,16},{65513,16},{65514,16},{0,0},{0,0},{0,0},{0,0},{0,0},{0,0}, 1442 {65515,16},{65516,16},{65517,16},{65518,16},{65519,16},{65520,16},{65521,16},{65522,16},{65523,16},{65524,16},{0,0},{0,0},{0,0},{0,0},{0,0}, 1443 {2041,11},{65525,16},{65526,16},{65527,16},{65528,16},{65529,16},{65530,16},{65531,16},{65532,16},{65533,16},{65534,16},{0,0},{0,0},{0,0},{0,0},{0,0} 1444 }; 1445 static const unsigned short UVAC_HT[256][2] = { 1446 {0,2},{1,2},{4,3},{10,4},{24,5},{25,5},{56,6},{120,7},{500,9},{1014,10},{4084,12},{0,0},{0,0},{0,0},{0,0},{0,0},{0,0}, 1447 {11,4},{57,6},{246,8},{501,9},{2038,11},{4085,12},{65416,16},{65417,16},{65418,16},{65419,16},{0,0},{0,0},{0,0},{0,0},{0,0},{0,0}, 1448 {26,5},{247,8},{1015,10},{4086,12},{32706,15},{65420,16},{65421,16},{65422,16},{65423,16},{65424,16},{0,0},{0,0},{0,0},{0,0},{0,0},{0,0}, 1449 {27,5},{248,8},{1016,10},{4087,12},{65425,16},{65426,16},{65427,16},{65428,16},{65429,16},{65430,16},{0,0},{0,0},{0,0},{0,0},{0,0},{0,0}, 1450 {58,6},{502,9},{65431,16},{65432,16},{65433,16},{65434,16},{65435,16},{65436,16},{65437,16},{65438,16},{0,0},{0,0},{0,0},{0,0},{0,0},{0,0}, 1451 {59,6},{1017,10},{65439,16},{65440,16},{65441,16},{65442,16},{65443,16},{65444,16},{65445,16},{65446,16},{0,0},{0,0},{0,0},{0,0},{0,0},{0,0}, 1452 {121,7},{2039,11},{65447,16},{65448,16},{65449,16},{65450,16},{65451,16},{65452,16},{65453,16},{65454,16},{0,0},{0,0},{0,0},{0,0},{0,0},{0,0}, 1453 {122,7},{2040,11},{65455,16},{65456,16},{65457,16},{65458,16},{65459,16},{65460,16},{65461,16},{65462,16},{0,0},{0,0},{0,0},{0,0},{0,0},{0,0}, 1454 {249,8},{65463,16},{65464,16},{65465,16},{65466,16},{65467,16},{65468,16},{65469,16},{65470,16},{65471,16},{0,0},{0,0},{0,0},{0,0},{0,0},{0,0}, 1455 {503,9},{65472,16},{65473,16},{65474,16},{65475,16},{65476,16},{65477,16},{65478,16},{65479,16},{65480,16},{0,0},{0,0},{0,0},{0,0},{0,0},{0,0}, 1456 {504,9},{65481,16},{65482,16},{65483,16},{65484,16},{65485,16},{65486,16},{65487,16},{65488,16},{65489,16},{0,0},{0,0},{0,0},{0,0},{0,0},{0,0}, 1457 {505,9},{65490,16},{65491,16},{65492,16},{65493,16},{65494,16},{65495,16},{65496,16},{65497,16},{65498,16},{0,0},{0,0},{0,0},{0,0},{0,0},{0,0}, 1458 {506,9},{65499,16},{65500,16},{65501,16},{65502,16},{65503,16},{65504,16},{65505,16},{65506,16},{65507,16},{0,0},{0,0},{0,0},{0,0},{0,0},{0,0}, 1459 {2041,11},{65508,16},{65509,16},{65510,16},{65511,16},{65512,16},{65513,16},{65514,16},{65515,16},{65516,16},{0,0},{0,0},{0,0},{0,0},{0,0},{0,0}, 1460 {16352,14},{65517,16},{65518,16},{65519,16},{65520,16},{65521,16},{65522,16},{65523,16},{65524,16},{65525,16},{0,0},{0,0},{0,0},{0,0},{0,0}, 1461 {1018,10},{32707,15},{65526,16},{65527,16},{65528,16},{65529,16},{65530,16},{65531,16},{65532,16},{65533,16},{65534,16},{0,0},{0,0},{0,0},{0,0},{0,0} 1462 }; 1463 static const int YQT[] = {16,11,10,16,24,40,51,61,12,12,14,19,26,58,60,55,14,13,16,24,40,57,69,56,14,17,22,29,51,87,80,62,18,22, 1464 37,56,68,109,103,77,24,35,55,64,81,104,113,92,49,64,78,87,103,121,120,101,72,92,95,98,112,100,103,99}; 1465 static const int UVQT[] = {17,18,24,47,99,99,99,99,18,21,26,66,99,99,99,99,24,26,56,99,99,99,99,99,47,66,99,99,99,99,99,99, 1466 99,99,99,99,99,99,99,99,99,99,99,99,99,99,99,99,99,99,99,99,99,99,99,99,99,99,99,99,99,99,99,99}; 1467 static const float aasf[] = { 1.0f * 2.828427125f, 1.387039845f * 2.828427125f, 1.306562965f * 2.828427125f, 1.175875602f * 2.828427125f, 1468 1.0f * 2.828427125f, 0.785694958f * 2.828427125f, 0.541196100f * 2.828427125f, 0.275899379f * 2.828427125f }; 1469 1470 int row, col, i, k, subsample; 1471 float fdtbl_Y[64], fdtbl_UV[64]; 1472 unsigned char YTable[64], UVTable[64]; 1473 1474 if(!data || !width || !height || comp > 4 || comp < 1) { 1475 return 0; 1476 } 1477 1478 quality = quality ? quality : 90; 1479 subsample = quality <= 90 ? 1 : 0; 1480 quality = quality < 1 ? 1 : quality > 100 ? 100 : quality; 1481 quality = quality < 50 ? 5000 / quality : 200 - quality * 2; 1482 1483 for(i = 0; i < 64; ++i) { 1484 int uvti, yti = (YQT[i]*quality+50)/100; 1485 YTable[stbiw__jpg_ZigZag[i]] = (unsigned char) (yti < 1 ? 1 : yti > 255 ? 255 : yti); 1486 uvti = (UVQT[i]*quality+50)/100; 1487 UVTable[stbiw__jpg_ZigZag[i]] = (unsigned char) (uvti < 1 ? 1 : uvti > 255 ? 255 : uvti); 1488 } 1489 1490 for(row = 0, k = 0; row < 8; ++row) { 1491 for(col = 0; col < 8; ++col, ++k) { 1492 fdtbl_Y[k] = 1 / (YTable [stbiw__jpg_ZigZag[k]] * aasf[row] * aasf[col]); 1493 fdtbl_UV[k] = 1 / (UVTable[stbiw__jpg_ZigZag[k]] * aasf[row] * aasf[col]); 1494 } 1495 } 1496 1497 // Write Headers 1498 { 1499 static const unsigned char head0[] = { 0xFF,0xD8,0xFF,0xE0,0,0x10,'J','F','I','F',0,1,1,0,0,1,0,1,0,0,0xFF,0xDB,0,0x84,0 }; 1500 static const unsigned char head2[] = { 0xFF,0xDA,0,0xC,3,1,0,2,0x11,3,0x11,0,0x3F,0 }; 1501 const unsigned char head1[] = { 0xFF,0xC0,0,0x11,8,(unsigned char)(height>>8),STBIW_UCHAR(height),(unsigned char)(width>>8),STBIW_UCHAR(width), 1502 3,1,(unsigned char)(subsample?0x22:0x11),0,2,0x11,1,3,0x11,1,0xFF,0xC4,0x01,0xA2,0 }; 1503 s->func(s->context, (void*)head0, sizeof(head0)); 1504 s->func(s->context, (void*)YTable, sizeof(YTable)); 1505 stbiw__putc(s, 1); 1506 s->func(s->context, UVTable, sizeof(UVTable)); 1507 s->func(s->context, (void*)head1, sizeof(head1)); 1508 s->func(s->context, (void*)(std_dc_luminance_nrcodes+1), sizeof(std_dc_luminance_nrcodes)-1); 1509 s->func(s->context, (void*)std_dc_luminance_values, sizeof(std_dc_luminance_values)); 1510 stbiw__putc(s, 0x10); // HTYACinfo 1511 s->func(s->context, (void*)(std_ac_luminance_nrcodes+1), sizeof(std_ac_luminance_nrcodes)-1); 1512 s->func(s->context, (void*)std_ac_luminance_values, sizeof(std_ac_luminance_values)); 1513 stbiw__putc(s, 1); // HTUDCinfo 1514 s->func(s->context, (void*)(std_dc_chrominance_nrcodes+1), sizeof(std_dc_chrominance_nrcodes)-1); 1515 s->func(s->context, (void*)std_dc_chrominance_values, sizeof(std_dc_chrominance_values)); 1516 stbiw__putc(s, 0x11); // HTUACinfo 1517 s->func(s->context, (void*)(std_ac_chrominance_nrcodes+1), sizeof(std_ac_chrominance_nrcodes)-1); 1518 s->func(s->context, (void*)std_ac_chrominance_values, sizeof(std_ac_chrominance_values)); 1519 s->func(s->context, (void*)head2, sizeof(head2)); 1520 } 1521 1522 // Encode 8x8 macroblocks 1523 { 1524 static const unsigned short fillBits[] = {0x7F, 7}; 1525 int DCY=0, DCU=0, DCV=0; 1526 int bitBuf=0, bitCnt=0; 1527 // comp == 2 is grey+alpha (alpha is ignored) 1528 int ofsG = comp > 2 ? 1 : 0, ofsB = comp > 2 ? 2 : 0; 1529 const unsigned char *dataR = (const unsigned char *)data; 1530 const unsigned char *dataG = dataR + ofsG; 1531 const unsigned char *dataB = dataR + ofsB; 1532 int x, y, pos; 1533 if(subsample) { 1534 for(y = 0; y < height; y += 16) { 1535 for(x = 0; x < width; x += 16) { 1536 float Y[256], U[256], V[256]; 1537 for(row = y, pos = 0; row < y+16; ++row) { 1538 // row >= height => use last input row 1539 int clamped_row = (row < height) ? row : height - 1; 1540 int base_p = (stbi__flip_vertically_on_write ? (height-1-clamped_row) : clamped_row)*width*comp; 1541 for(col = x; col < x+16; ++col, ++pos) { 1542 // if col >= width => use pixel from last input column 1543 int p = base_p + ((col < width) ? col : (width-1))*comp; 1544 float r = dataR[p], g = dataG[p], b = dataB[p]; 1545 Y[pos]= +0.29900f*r + 0.58700f*g + 0.11400f*b - 128; 1546 U[pos]= -0.16874f*r - 0.33126f*g + 0.50000f*b; 1547 V[pos]= +0.50000f*r - 0.41869f*g - 0.08131f*b; 1548 } 1549 } 1550 DCY = stbiw__jpg_processDU(s, &bitBuf, &bitCnt, Y+0, 16, fdtbl_Y, DCY, YDC_HT, YAC_HT); 1551 DCY = stbiw__jpg_processDU(s, &bitBuf, &bitCnt, Y+8, 16, fdtbl_Y, DCY, YDC_HT, YAC_HT); 1552 DCY = stbiw__jpg_processDU(s, &bitBuf, &bitCnt, Y+128, 16, fdtbl_Y, DCY, YDC_HT, YAC_HT); 1553 DCY = stbiw__jpg_processDU(s, &bitBuf, &bitCnt, Y+136, 16, fdtbl_Y, DCY, YDC_HT, YAC_HT); 1554 1555 // subsample U,V 1556 { 1557 float subU[64], subV[64]; 1558 int yy, xx; 1559 for(yy = 0, pos = 0; yy < 8; ++yy) { 1560 for(xx = 0; xx < 8; ++xx, ++pos) { 1561 int j = yy*32+xx*2; 1562 subU[pos] = (U[j+0] + U[j+1] + U[j+16] + U[j+17]) * 0.25f; 1563 subV[pos] = (V[j+0] + V[j+1] + V[j+16] + V[j+17]) * 0.25f; 1564 } 1565 } 1566 DCU = stbiw__jpg_processDU(s, &bitBuf, &bitCnt, subU, 8, fdtbl_UV, DCU, UVDC_HT, UVAC_HT); 1567 DCV = stbiw__jpg_processDU(s, &bitBuf, &bitCnt, subV, 8, fdtbl_UV, DCV, UVDC_HT, UVAC_HT); 1568 } 1569 } 1570 } 1571 } else { 1572 for(y = 0; y < height; y += 8) { 1573 for(x = 0; x < width; x += 8) { 1574 float Y[64], U[64], V[64]; 1575 for(row = y, pos = 0; row < y+8; ++row) { 1576 // row >= height => use last input row 1577 int clamped_row = (row < height) ? row : height - 1; 1578 int base_p = (stbi__flip_vertically_on_write ? (height-1-clamped_row) : clamped_row)*width*comp; 1579 for(col = x; col < x+8; ++col, ++pos) { 1580 // if col >= width => use pixel from last input column 1581 int p = base_p + ((col < width) ? col : (width-1))*comp; 1582 float r = dataR[p], g = dataG[p], b = dataB[p]; 1583 Y[pos]= +0.29900f*r + 0.58700f*g + 0.11400f*b - 128; 1584 U[pos]= -0.16874f*r - 0.33126f*g + 0.50000f*b; 1585 V[pos]= +0.50000f*r - 0.41869f*g - 0.08131f*b; 1586 } 1587 } 1588 1589 DCY = stbiw__jpg_processDU(s, &bitBuf, &bitCnt, Y, 8, fdtbl_Y, DCY, YDC_HT, YAC_HT); 1590 DCU = stbiw__jpg_processDU(s, &bitBuf, &bitCnt, U, 8, fdtbl_UV, DCU, UVDC_HT, UVAC_HT); 1591 DCV = stbiw__jpg_processDU(s, &bitBuf, &bitCnt, V, 8, fdtbl_UV, DCV, UVDC_HT, UVAC_HT); 1592 } 1593 } 1594 } 1595 1596 // Do the bit alignment of the EOI marker 1597 stbiw__jpg_writeBits(s, &bitBuf, &bitCnt, fillBits); 1598 } 1599 1600 // EOI 1601 stbiw__putc(s, 0xFF); 1602 stbiw__putc(s, 0xD9); 1603 1604 return 1; 1605 } 1606 1607 STBIWDEF int stbi_write_jpg_to_func(stbi_write_func *func, void *context, int x, int y, int comp, const void *data, int quality) 1608 { 1609 stbi__write_context s = { 0 }; 1610 stbi__start_write_callbacks(&s, func, context); 1611 return stbi_write_jpg_core(&s, x, y, comp, (void *) data, quality); 1612 } 1613 1614 1615 #ifndef STBI_WRITE_NO_STDIO 1616 STBIWDEF int stbi_write_jpg(char const *filename, int x, int y, int comp, const void *data, int quality) 1617 { 1618 stbi__write_context s = { 0 }; 1619 if (stbi__start_write_file(&s,filename)) { 1620 int r = stbi_write_jpg_core(&s, x, y, comp, data, quality); 1621 stbi__end_write_file(&s); 1622 return r; 1623 } else 1624 return 0; 1625 } 1626 #endif 1627 1628 #endif // STB_IMAGE_WRITE_IMPLEMENTATION 1629 1630 /* Revision history 1631 1.16 (2021-07-11) 1632 make Deflate code emit uncompressed blocks when it would otherwise expand 1633 support writing BMPs with alpha channel 1634 1.15 (2020-07-13) unknown 1635 1.14 (2020-02-02) updated JPEG writer to downsample chroma channels 1636 1.13 1637 1.12 1638 1.11 (2019-08-11) 1639 1640 1.10 (2019-02-07) 1641 support utf8 filenames in Windows; fix warnings and platform ifdefs 1642 1.09 (2018-02-11) 1643 fix typo in zlib quality API, improve STB_I_W_STATIC in C++ 1644 1.08 (2018-01-29) 1645 add stbi__flip_vertically_on_write, external zlib, zlib quality, choose PNG filter 1646 1.07 (2017-07-24) 1647 doc fix 1648 1.06 (2017-07-23) 1649 writing JPEG (using Jon Olick's code) 1650 1.05 ??? 1651 1.04 (2017-03-03) 1652 monochrome BMP expansion 1653 1.03 ??? 1654 1.02 (2016-04-02) 1655 avoid allocating large structures on the stack 1656 1.01 (2016-01-16) 1657 STBIW_REALLOC_SIZED: support allocators with no realloc support 1658 avoid race-condition in crc initialization 1659 minor compile issues 1660 1.00 (2015-09-14) 1661 installable file IO function 1662 0.99 (2015-09-13) 1663 warning fixes; TGA rle support 1664 0.98 (2015-04-08) 1665 added STBIW_MALLOC, STBIW_ASSERT etc 1666 0.97 (2015-01-18) 1667 fixed HDR asserts, rewrote HDR rle logic 1668 0.96 (2015-01-17) 1669 add HDR output 1670 fix monochrome BMP 1671 0.95 (2014-08-17) 1672 add monochrome TGA output 1673 0.94 (2014-05-31) 1674 rename private functions to avoid conflicts with stb_image.h 1675 0.93 (2014-05-27) 1676 warning fixes 1677 0.92 (2010-08-01) 1678 casts to unsigned char to fix warnings 1679 0.91 (2010-07-17) 1680 first public release 1681 0.90 first internal release 1682 */ 1683 1684 /* 1685 ------------------------------------------------------------------------------ 1686 This software is available under 2 licenses -- choose whichever you prefer. 1687 ------------------------------------------------------------------------------ 1688 ALTERNATIVE A - MIT License 1689 Copyright (c) 2017 Sean Barrett 1690 Permission is hereby granted, free of charge, to any person obtaining a copy of 1691 this software and associated documentation files (the "Software"), to deal in 1692 the Software without restriction, including without limitation the rights to 1693 use, copy, modify, merge, publish, distribute, sublicense, and/or sell copies 1694 of the Software, and to permit persons to whom the Software is furnished to do 1695 so, subject to the following conditions: 1696 The above copyright notice and this permission notice shall be included in all 1697 copies or substantial portions of the Software. 1698 THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR 1699 IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY, 1700 FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT. IN NO EVENT SHALL THE 1701 AUTHORS OR COPYRIGHT HOLDERS BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER 1702 LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING FROM, 1703 OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN THE 1704 SOFTWARE. 1705 ------------------------------------------------------------------------------ 1706 ALTERNATIVE B - Public Domain (www.unlicense.org) 1707 This is free and unencumbered software released into the public domain. 1708 Anyone is free to copy, modify, publish, use, compile, sell, or distribute this 1709 software, either in source code form or as a compiled binary, for any purpose, 1710 commercial or non-commercial, and by any means. 1711 In jurisdictions that recognize copyright laws, the author or authors of this 1712 software dedicate any and all copyright interest in the software to the public 1713 domain. We make this dedication for the benefit of the public at large and to 1714 the detriment of our heirs and successors. We intend this dedication to be an 1715 overt act of relinquishment in perpetuity of all present and future rights to 1716 this software under copyright law. 1717 THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR 1718 IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY, 1719 FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT. IN NO EVENT SHALL THE 1720 AUTHORS BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER LIABILITY, WHETHER IN AN 1721 ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING FROM, OUT OF OR IN CONNECTION 1722 WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN THE SOFTWARE. 1723 ------------------------------------------------------------------------------ 1724 */