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  1. /* stb_image_write - v1.10 - public domain - http://nothings.org/stb/stb_image_write.h
  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. Before #including,
  5. #define STB_IMAGE_WRITE_IMPLEMENTATION
  6. in the file that you want to have the implementation.
  7. Will probably not work correctly with strict-aliasing optimizations.
  8. If using a modern Microsoft Compiler, non-safe versions of CRT calls may cause
  9. compilation warnings or even errors. To avoid this, also before #including,
  10. #define STBI_MSC_SECURE_CRT
  11. ABOUT:
  12. This header file is a library for writing images to C stdio or a callback.
  13. The PNG output is not optimal; it is 20-50% larger than the file
  14. written by a decent optimizing implementation; though providing a custom
  15. zlib compress function (see STBIW_ZLIB_COMPRESS) can mitigate that.
  16. This library is designed for source code compactness and simplicity,
  17. not optimal image file size or run-time performance.
  18. BUILDING:
  19. You can #define STBIW_ASSERT(x) before the #include to avoid using assert.h.
  20. You can #define STBIW_MALLOC(), STBIW_REALLOC(), and STBIW_FREE() to replace
  21. malloc,realloc,free.
  22. You can #define STBIW_MEMMOVE() to replace memmove()
  23. You can #define STBIW_ZLIB_COMPRESS to use a custom zlib-style compress function
  24. for PNG compression (instead of the builtin one), it must have the following signature:
  25. unsigned char * my_compress(unsigned char *data, int data_len, int *out_len, int quality);
  26. The returned data will be freed with STBIW_FREE() (free() by default),
  27. so it must be heap allocated with STBIW_MALLOC() (malloc() by default),
  28. UNICODE:
  29. If compiling for Windows and you wish to use Unicode filenames, compile
  30. with
  31. #define STBIW_WINDOWS_UTF8
  32. and pass utf8-encoded filenames. Call stbiw_convert_wchar_to_utf8 to convert
  33. Windows wchar_t filenames to utf8.
  34. USAGE:
  35. There are five functions, one for each image file format:
  36. int stbi_write_png(char const *filename, int w, int h, int comp, const void *data, int stride_in_bytes);
  37. int stbi_write_bmp(char const *filename, int w, int h, int comp, const void *data);
  38. int stbi_write_tga(char const *filename, int w, int h, int comp, const void *data);
  39. int stbi_write_jpg(char const *filename, int w, int h, int comp, const void *data, int quality);
  40. int stbi_write_hdr(char const *filename, int w, int h, int comp, const float *data);
  41. void stbi_flip_vertically_on_write(int flag); // flag is non-zero to flip data vertically
  42. There are also five equivalent functions that use an arbitrary write function. You are
  43. expected to open/close your file-equivalent before and after calling these:
  44. 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);
  45. int stbi_write_bmp_to_func(stbi_write_func *func, void *context, int w, int h, int comp, const void *data);
  46. int stbi_write_tga_to_func(stbi_write_func *func, void *context, int w, int h, int comp, const void *data);
  47. int stbi_write_hdr_to_func(stbi_write_func *func, void *context, int w, int h, int comp, const float *data);
  48. int stbi_write_jpg_to_func(stbi_write_func *func, void *context, int x, int y, int comp, const void *data, int quality);
  49. where the callback is:
  50. void stbi_write_func(void *context, void *data, int size);
  51. You can configure it with these global variables:
  52. int stbi_write_tga_with_rle; // defaults to true; set to 0 to disable RLE
  53. int stbi_write_png_compression_level; // defaults to 8; set to higher for more compression
  54. int stbi_write_force_png_filter; // defaults to -1; set to 0..5 to force a filter mode
  55. You can define STBI_WRITE_NO_STDIO to disable the file variant of these
  56. functions, so the library will not use stdio.h at all. However, this will
  57. also disable HDR writing, because it requires stdio for formatted output.
  58. Each function returns 0 on failure and non-0 on success.
  59. The functions create an image file defined by the parameters. The image
  60. is a rectangle of pixels stored from left-to-right, top-to-bottom.
  61. Each pixel contains 'comp' channels of data stored interleaved with 8-bits
  62. per channel, in the following order: 1=Y, 2=YA, 3=RGB, 4=RGBA. (Y is
  63. monochrome color.) The rectangle is 'w' pixels wide and 'h' pixels tall.
  64. The *data pointer points to the first byte of the top-left-most pixel.
  65. For PNG, "stride_in_bytes" is the distance in bytes from the first byte of
  66. a row of pixels to the first byte of the next row of pixels.
  67. PNG creates output files with the same number of components as the input.
  68. The BMP format expands Y to RGB in the file format and does not
  69. output alpha.
  70. PNG supports writing rectangles of data even when the bytes storing rows of
  71. data are not consecutive in memory (e.g. sub-rectangles of a larger image),
  72. by supplying the stride between the beginning of adjacent rows. The other
  73. formats do not. (Thus you cannot write a native-format BMP through the BMP
  74. writer, both because it is in BGR order and because it may have padding
  75. at the end of the line.)
  76. PNG allows you to set the deflate compression level by setting the global
  77. variable 'stbi_write_png_compression_level' (it defaults to 8).
  78. HDR expects linear float data. Since the format is always 32-bit rgb(e)
  79. data, alpha (if provided) is discarded, and for monochrome data it is
  80. replicated across all three channels.
  81. TGA supports RLE or non-RLE compressed data. To use non-RLE-compressed
  82. data, set the global variable 'stbi_write_tga_with_rle' to 0.
  83. JPEG does ignore alpha channels in input data; quality is between 1 and 100.
  84. Higher quality looks better but results in a bigger image.
  85. JPEG baseline (no JPEG progressive).
  86. CREDITS:
  87. Sean Barrett - PNG/BMP/TGA
  88. Baldur Karlsson - HDR
  89. Jean-Sebastien Guay - TGA monochrome
  90. Tim Kelsey - misc enhancements
  91. Alan Hickman - TGA RLE
  92. Emmanuel Julien - initial file IO callback implementation
  93. Jon Olick - original jo_jpeg.cpp code
  94. Daniel Gibson - integrate JPEG, allow external zlib
  95. Aarni Koskela - allow choosing PNG filter
  96. bugfixes:
  97. github:Chribba
  98. Guillaume Chereau
  99. github:jry2
  100. github:romigrou
  101. Sergio Gonzalez
  102. Jonas Karlsson
  103. Filip Wasil
  104. Thatcher Ulrich
  105. github:poppolopoppo
  106. Patrick Boettcher
  107. github:xeekworx
  108. Cap Petschulat
  109. Simon Rodriguez
  110. Ivan Tikhonov
  111. github:ignotion
  112. Adam Schackart
  113. LICENSE
  114. See end of file for license information.
  115. */
  116. #ifndef INCLUDE_STB_IMAGE_WRITE_H
  117. #define INCLUDE_STB_IMAGE_WRITE_H
  118. #include <stdlib.h>
  119. // if STB_IMAGE_WRITE_STATIC causes problems, try defining STBIWDEF to 'inline' or 'static inline'
  120. #ifndef STBIWDEF
  121. #ifdef STB_IMAGE_WRITE_STATIC
  122. #define STBIWDEF static
  123. #else
  124. #ifdef __cplusplus
  125. #define STBIWDEF extern "C"
  126. #else
  127. #define STBIWDEF extern
  128. #endif
  129. #endif
  130. #endif
  131. #ifndef STB_IMAGE_WRITE_STATIC // C++ forbids static forward declarations
  132. extern int stbi_write_tga_with_rle;
  133. extern int stbi_write_png_compression_level;
  134. extern int stbi_write_force_png_filter;
  135. #endif
  136. #ifndef STBI_WRITE_NO_STDIO
  137. STBIWDEF int stbi_write_png(char const *filename, int w, int h, int comp, const void *data, int stride_in_bytes);
  138. STBIWDEF int stbi_write_bmp(char const *filename, int w, int h, int comp, const void *data);
  139. STBIWDEF int stbi_write_tga(char const *filename, int w, int h, int comp, const void *data);
  140. STBIWDEF int stbi_write_hdr(char const *filename, int w, int h, int comp, const float *data);
  141. STBIWDEF int stbi_write_jpg(char const *filename, int x, int y, int comp, const void *data, int quality);
  142. #ifdef STBI_WINDOWS_UTF8
  143. STBIWDEF int stbiw_convert_wchar_to_utf8(char *buffer, size_t bufferlen, const wchar_t* input);
  144. #endif
  145. #endif
  146. typedef void stbi_write_func(void *context, void *data, int size);
  147. 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);
  148. STBIWDEF int stbi_write_bmp_to_func(stbi_write_func *func, void *context, int w, int h, int comp, const void *data);
  149. STBIWDEF int stbi_write_tga_to_func(stbi_write_func *func, void *context, int w, int h, int comp, const void *data);
  150. STBIWDEF int stbi_write_hdr_to_func(stbi_write_func *func, void *context, int w, int h, int comp, const float *data);
  151. STBIWDEF int stbi_write_jpg_to_func(stbi_write_func *func, void *context, int x, int y, int comp, const void *data, int quality);
  152. STBIWDEF void stbi_flip_vertically_on_write(int flip_boolean);
  153. #endif//INCLUDE_STB_IMAGE_WRITE_H
  154. #ifdef STB_IMAGE_WRITE_IMPLEMENTATION
  155. #ifdef _WIN32
  156. #ifndef _CRT_SECURE_NO_WARNINGS
  157. #define _CRT_SECURE_NO_WARNINGS
  158. #endif
  159. #ifndef _CRT_NONSTDC_NO_DEPRECATE
  160. #define _CRT_NONSTDC_NO_DEPRECATE
  161. #endif
  162. #endif
  163. #ifndef STBI_WRITE_NO_STDIO
  164. #include <stdio.h>
  165. #endif // STBI_WRITE_NO_STDIO
  166. #include <stdarg.h>
  167. #include <stdlib.h>
  168. #include <string.h>
  169. #include <math.h>
  170. #if defined(STBIW_MALLOC) && defined(STBIW_FREE) && (defined(STBIW_REALLOC) || defined(STBIW_REALLOC_SIZED))
  171. // ok
  172. #elif !defined(STBIW_MALLOC) && !defined(STBIW_FREE) && !defined(STBIW_REALLOC) && !defined(STBIW_REALLOC_SIZED)
  173. // ok
  174. #else
  175. #error "Must define all or none of STBIW_MALLOC, STBIW_FREE, and STBIW_REALLOC (or STBIW_REALLOC_SIZED)."
  176. #endif
  177. #ifndef STBIW_MALLOC
  178. #define STBIW_MALLOC(sz) malloc(sz)
  179. #define STBIW_REALLOC(p,newsz) realloc(p,newsz)
  180. #define STBIW_FREE(p) free(p)
  181. #endif
  182. #ifndef STBIW_REALLOC_SIZED
  183. #define STBIW_REALLOC_SIZED(p,oldsz,newsz) STBIW_REALLOC(p,newsz)
  184. #endif
  185. #ifndef STBIW_MEMMOVE
  186. #define STBIW_MEMMOVE(a,b,sz) memmove(a,b,sz)
  187. #endif
  188. #ifndef STBIW_ASSERT
  189. #include <assert.h>
  190. #define STBIW_ASSERT(x) assert(x)
  191. #endif
  192. #define STBIW_UCHAR(x) (unsigned char) ((x) & 0xff)
  193. #ifdef STB_IMAGE_WRITE_STATIC
  194. static int stbi__flip_vertically_on_write=0;
  195. static int stbi_write_png_compression_level = 8;
  196. static int stbi_write_tga_with_rle = 1;
  197. static int stbi_write_force_png_filter = -1;
  198. #else
  199. int stbi_write_png_compression_level = 8;
  200. int stbi__flip_vertically_on_write=0;
  201. int stbi_write_tga_with_rle = 1;
  202. int stbi_write_force_png_filter = -1;
  203. #endif
  204. STBIWDEF void stbi_flip_vertically_on_write(int flag)
  205. {
  206. stbi__flip_vertically_on_write = flag;
  207. }
  208. typedef struct
  209. {
  210. stbi_write_func *func;
  211. void *context;
  212. } stbi__write_context;
  213. // initialize a callback-based context
  214. static void stbi__start_write_callbacks(stbi__write_context *s, stbi_write_func *c, void *context)
  215. {
  216. s->func = c;
  217. s->context = context;
  218. }
  219. #ifndef STBI_WRITE_NO_STDIO
  220. static void stbi__stdio_write(void *context, void *data, int size)
  221. {
  222. fwrite(data,1,size,(FILE*) context);
  223. }
  224. #if defined(_MSC_VER) && defined(STBI_WINDOWS_UTF8)
  225. #ifdef __cplusplus
  226. #define STBIW_EXTERN extern "C"
  227. #else
  228. #define STBIW_EXTERN extern
  229. #endif
  230. STBIW_EXTERN __declspec(dllimport) int __stdcall MultiByteToWideChar(unsigned int cp, unsigned long flags, const char *str, int cbmb, wchar_t *widestr, int cchwide);
  231. 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);
  232. STBIWDEF int stbiw_convert_wchar_to_utf8(char *buffer, size_t bufferlen, const wchar_t* input)
  233. {
  234. return WideCharToMultiByte(65001 /* UTF8 */, 0, input, -1, buffer, bufferlen, NULL, NULL);
  235. }
  236. #endif
  237. static FILE *stbiw__fopen(char const *filename, char const *mode)
  238. {
  239. FILE *f;
  240. #if defined(_MSC_VER) && defined(STBI_WINDOWS_UTF8)
  241. wchar_t wMode[64];
  242. wchar_t wFilename[1024];
  243. if (0 == MultiByteToWideChar(65001 /* UTF8 */, 0, filename, -1, wFilename, sizeof(wFilename)))
  244. return 0;
  245. if (0 == MultiByteToWideChar(65001 /* UTF8 */, 0, mode, -1, wMode, sizeof(wMode)))
  246. return 0;
  247. #if _MSC_VER >= 1400
  248. if (0 != _wfopen_s(&f, wFilename, wMode))
  249. f = 0;
  250. #else
  251. f = _wfopen(wFilename, wMode);
  252. #endif
  253. #elif defined(_MSC_VER) && _MSC_VER >= 1400
  254. if (0 != fopen_s(&f, filename, mode))
  255. f=0;
  256. #else
  257. f = fopen(filename, mode);
  258. #endif
  259. return f;
  260. }
  261. static int stbi__start_write_file(stbi__write_context *s, const char *filename)
  262. {
  263. FILE *f = stbiw__fopen(filename, "wb");
  264. stbi__start_write_callbacks(s, stbi__stdio_write, (void *) f);
  265. return f != NULL;
  266. }
  267. static void stbi__end_write_file(stbi__write_context *s)
  268. {
  269. fclose((FILE *)s->context);
  270. }
  271. #endif // !STBI_WRITE_NO_STDIO
  272. typedef unsigned int stbiw_uint32;
  273. typedef int stb_image_write_test[sizeof(stbiw_uint32)==4 ? 1 : -1];
  274. static void stbiw__writefv(stbi__write_context *s, const char *fmt, va_list v)
  275. {
  276. while (*fmt) {
  277. switch (*fmt++) {
  278. case ' ': break;
  279. case '1': { unsigned char x = STBIW_UCHAR(va_arg(v, int));
  280. s->func(s->context,&x,1);
  281. break; }
  282. case '2': { int x = va_arg(v,int);
  283. unsigned char b[2];
  284. b[0] = STBIW_UCHAR(x);
  285. b[1] = STBIW_UCHAR(x>>8);
  286. s->func(s->context,b,2);
  287. break; }
  288. case '4': { stbiw_uint32 x = va_arg(v,int);
  289. unsigned char b[4];
  290. b[0]=STBIW_UCHAR(x);
  291. b[1]=STBIW_UCHAR(x>>8);
  292. b[2]=STBIW_UCHAR(x>>16);
  293. b[3]=STBIW_UCHAR(x>>24);
  294. s->func(s->context,b,4);
  295. break; }
  296. default:
  297. STBIW_ASSERT(0);
  298. return;
  299. }
  300. }
  301. }
  302. static void stbiw__writef(stbi__write_context *s, const char *fmt, ...)
  303. {
  304. va_list v;
  305. va_start(v, fmt);
  306. stbiw__writefv(s, fmt, v);
  307. va_end(v);
  308. }
  309. static void stbiw__putc(stbi__write_context *s, unsigned char c)
  310. {
  311. s->func(s->context, &c, 1);
  312. }
  313. static void stbiw__write3(stbi__write_context *s, unsigned char a, unsigned char b, unsigned char c)
  314. {
  315. unsigned char arr[3];
  316. arr[0] = a, arr[1] = b, arr[2] = c;
  317. s->func(s->context, arr, 3);
  318. }
  319. static void stbiw__write_pixel(stbi__write_context *s, int rgb_dir, int comp, int write_alpha, int expand_mono, unsigned char *d)
  320. {
  321. unsigned char bg[3] = { 255, 0, 255}, px[3];
  322. int k;
  323. if (write_alpha < 0)
  324. s->func(s->context, &d[comp - 1], 1);
  325. switch (comp) {
  326. case 2: // 2 pixels = mono + alpha, alpha is written separately, so same as 1-channel case
  327. case 1:
  328. if (expand_mono)
  329. stbiw__write3(s, d[0], d[0], d[0]); // monochrome bmp
  330. else
  331. s->func(s->context, d, 1); // monochrome TGA
  332. break;
  333. case 4:
  334. if (!write_alpha) {
  335. // composite against pink background
  336. for (k = 0; k < 3; ++k)
  337. px[k] = bg[k] + ((d[k] - bg[k]) * d[3]) / 255;
  338. stbiw__write3(s, px[1 - rgb_dir], px[1], px[1 + rgb_dir]);
  339. break;
  340. }
  341. /* FALLTHROUGH */
  342. case 3:
  343. stbiw__write3(s, d[1 - rgb_dir], d[1], d[1 + rgb_dir]);
  344. break;
  345. }
  346. if (write_alpha > 0)
  347. s->func(s->context, &d[comp - 1], 1);
  348. }
  349. 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)
  350. {
  351. stbiw_uint32 zero = 0;
  352. int i,j, j_end;
  353. if (y <= 0)
  354. return;
  355. if (stbi__flip_vertically_on_write)
  356. vdir *= -1;
  357. if (vdir < 0)
  358. j_end = -1, j = y-1;
  359. else
  360. j_end = y, j = 0;
  361. for (; j != j_end; j += vdir) {
  362. for (i=0; i < x; ++i) {
  363. unsigned char *d = (unsigned char *) data + (j*x+i)*comp;
  364. stbiw__write_pixel(s, rgb_dir, comp, write_alpha, expand_mono, d);
  365. }
  366. s->func(s->context, &zero, scanline_pad);
  367. }
  368. }
  369. 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, ...)
  370. {
  371. if (y < 0 || x < 0) {
  372. return 0;
  373. } else {
  374. va_list v;
  375. va_start(v, fmt);
  376. stbiw__writefv(s, fmt, v);
  377. va_end(v);
  378. stbiw__write_pixels(s,rgb_dir,vdir,x,y,comp,data,alpha,pad, expand_mono);
  379. return 1;
  380. }
  381. }
  382. static int stbi_write_bmp_core(stbi__write_context *s, int x, int y, int comp, const void *data)
  383. {
  384. int pad = (-x*3) & 3;
  385. return stbiw__outfile(s,-1,-1,x,y,comp,1,(void *) data,0,pad,
  386. "11 4 22 4" "4 44 22 444444",
  387. 'B', 'M', 14+40+(x*3+pad)*y, 0,0, 14+40, // file header
  388. 40, x,y, 1,24, 0,0,0,0,0,0); // bitmap header
  389. }
  390. STBIWDEF int stbi_write_bmp_to_func(stbi_write_func *func, void *context, int x, int y, int comp, const void *data)
  391. {
  392. stbi__write_context s;
  393. stbi__start_write_callbacks(&s, func, context);
  394. return stbi_write_bmp_core(&s, x, y, comp, data);
  395. }
  396. #ifndef STBI_WRITE_NO_STDIO
  397. STBIWDEF int stbi_write_bmp(char const *filename, int x, int y, int comp, const void *data)
  398. {
  399. stbi__write_context s;
  400. if (stbi__start_write_file(&s,filename)) {
  401. int r = stbi_write_bmp_core(&s, x, y, comp, data);
  402. stbi__end_write_file(&s);
  403. return r;
  404. } else
  405. return 0;
  406. }
  407. #endif //!STBI_WRITE_NO_STDIO
  408. static int stbi_write_tga_core(stbi__write_context *s, int x, int y, int comp, void *data)
  409. {
  410. int has_alpha = (comp == 2 || comp == 4);
  411. int colorbytes = has_alpha ? comp-1 : comp;
  412. int format = colorbytes < 2 ? 3 : 2; // 3 color channels (RGB/RGBA) = 2, 1 color channel (Y/YA) = 3
  413. if (y < 0 || x < 0)
  414. return 0;
  415. if (!stbi_write_tga_with_rle) {
  416. return stbiw__outfile(s, -1, -1, x, y, comp, 0, (void *) data, has_alpha, 0,
  417. "111 221 2222 11", 0, 0, format, 0, 0, 0, 0, 0, x, y, (colorbytes + has_alpha) * 8, has_alpha * 8);
  418. } else {
  419. int i,j,k;
  420. int jend, jdir;
  421. 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);
  422. if (stbi__flip_vertically_on_write) {
  423. j = 0;
  424. jend = y;
  425. jdir = 1;
  426. } else {
  427. j = y-1;
  428. jend = -1;
  429. jdir = -1;
  430. }
  431. for (; j != jend; j += jdir) {
  432. unsigned char *row = (unsigned char *) data + j * x * comp;
  433. int len;
  434. for (i = 0; i < x; i += len) {
  435. unsigned char *begin = row + i * comp;
  436. int diff = 1;
  437. len = 1;
  438. if (i < x - 1) {
  439. ++len;
  440. diff = memcmp(begin, row + (i + 1) * comp, comp);
  441. if (diff) {
  442. const unsigned char *prev = begin;
  443. for (k = i + 2; k < x && len < 128; ++k) {
  444. if (memcmp(prev, row + k * comp, comp)) {
  445. prev += comp;
  446. ++len;
  447. } else {
  448. --len;
  449. break;
  450. }
  451. }
  452. } else {
  453. for (k = i + 2; k < x && len < 128; ++k) {
  454. if (!memcmp(begin, row + k * comp, comp)) {
  455. ++len;
  456. } else {
  457. break;
  458. }
  459. }
  460. }
  461. }
  462. if (diff) {
  463. unsigned char header = STBIW_UCHAR(len - 1);
  464. s->func(s->context, &header, 1);
  465. for (k = 0; k < len; ++k) {
  466. stbiw__write_pixel(s, -1, comp, has_alpha, 0, begin + k * comp);
  467. }
  468. } else {
  469. unsigned char header = STBIW_UCHAR(len - 129);
  470. s->func(s->context, &header, 1);
  471. stbiw__write_pixel(s, -1, comp, has_alpha, 0, begin);
  472. }
  473. }
  474. }
  475. }
  476. return 1;
  477. }
  478. STBIWDEF int stbi_write_tga_to_func(stbi_write_func *func, void *context, int x, int y, int comp, const void *data)
  479. {
  480. stbi__write_context s;
  481. stbi__start_write_callbacks(&s, func, context);
  482. return stbi_write_tga_core(&s, x, y, comp, (void *) data);
  483. }
  484. #ifndef STBI_WRITE_NO_STDIO
  485. STBIWDEF int stbi_write_tga(char const *filename, int x, int y, int comp, const void *data)
  486. {
  487. stbi__write_context s;
  488. if (stbi__start_write_file(&s,filename)) {
  489. int r = stbi_write_tga_core(&s, x, y, comp, (void *) data);
  490. stbi__end_write_file(&s);
  491. return r;
  492. } else
  493. return 0;
  494. }
  495. #endif
  496. // *************************************************************************************************
  497. // Radiance RGBE HDR writer
  498. // by Baldur Karlsson
  499. #define stbiw__max(a, b) ((a) > (b) ? (a) : (b))
  500. static void stbiw__linear_to_rgbe(unsigned char *rgbe, float *linear)
  501. {
  502. int exponent;
  503. float maxcomp = stbiw__max(linear[0], stbiw__max(linear[1], linear[2]));
  504. if (maxcomp < 1e-32f) {
  505. rgbe[0] = rgbe[1] = rgbe[2] = rgbe[3] = 0;
  506. } else {
  507. float normalize = (float) frexp(maxcomp, &exponent) * 256.0f/maxcomp;
  508. rgbe[0] = (unsigned char)(linear[0] * normalize);
  509. rgbe[1] = (unsigned char)(linear[1] * normalize);
  510. rgbe[2] = (unsigned char)(linear[2] * normalize);
  511. rgbe[3] = (unsigned char)(exponent + 128);
  512. }
  513. }
  514. static void stbiw__write_run_data(stbi__write_context *s, int length, unsigned char databyte)
  515. {
  516. unsigned char lengthbyte = STBIW_UCHAR(length+128);
  517. STBIW_ASSERT(length+128 <= 255);
  518. s->func(s->context, &lengthbyte, 1);
  519. s->func(s->context, &databyte, 1);
  520. }
  521. static void stbiw__write_dump_data(stbi__write_context *s, int length, unsigned char *data)
  522. {
  523. unsigned char lengthbyte = STBIW_UCHAR(length);
  524. STBIW_ASSERT(length <= 128); // inconsistent with spec but consistent with official code
  525. s->func(s->context, &lengthbyte, 1);
  526. s->func(s->context, data, length);
  527. }
  528. static void stbiw__write_hdr_scanline(stbi__write_context *s, int width, int ncomp, unsigned char *scratch, float *scanline)
  529. {
  530. unsigned char scanlineheader[4] = { 2, 2, 0, 0 };
  531. unsigned char rgbe[4];
  532. float linear[3];
  533. int x;
  534. scanlineheader[2] = (width&0xff00)>>8;
  535. scanlineheader[3] = (width&0x00ff);
  536. /* skip RLE for images too small or large */
  537. if (width < 8 || width >= 32768) {
  538. for (x=0; x < width; x++) {
  539. switch (ncomp) {
  540. case 4: /* fallthrough */
  541. case 3: linear[2] = scanline[x*ncomp + 2];
  542. linear[1] = scanline[x*ncomp + 1];
  543. linear[0] = scanline[x*ncomp + 0];
  544. break;
  545. default:
  546. linear[0] = linear[1] = linear[2] = scanline[x*ncomp + 0];
  547. break;
  548. }
  549. stbiw__linear_to_rgbe(rgbe, linear);
  550. s->func(s->context, rgbe, 4);
  551. }
  552. } else {
  553. int c,r;
  554. /* encode into scratch buffer */
  555. for (x=0; x < width; x++) {
  556. switch(ncomp) {
  557. case 4: /* fallthrough */
  558. case 3: linear[2] = scanline[x*ncomp + 2];
  559. linear[1] = scanline[x*ncomp + 1];
  560. linear[0] = scanline[x*ncomp + 0];
  561. break;
  562. default:
  563. linear[0] = linear[1] = linear[2] = scanline[x*ncomp + 0];
  564. break;
  565. }
  566. stbiw__linear_to_rgbe(rgbe, linear);
  567. scratch[x + width*0] = rgbe[0];
  568. scratch[x + width*1] = rgbe[1];
  569. scratch[x + width*2] = rgbe[2];
  570. scratch[x + width*3] = rgbe[3];
  571. }
  572. s->func(s->context, scanlineheader, 4);
  573. /* RLE each component separately */
  574. for (c=0; c < 4; c++) {
  575. unsigned char *comp = &scratch[width*c];
  576. x = 0;
  577. while (x < width) {
  578. // find first run
  579. r = x;
  580. while (r+2 < width) {
  581. if (comp[r] == comp[r+1] && comp[r] == comp[r+2])
  582. break;
  583. ++r;
  584. }
  585. if (r+2 >= width)
  586. r = width;
  587. // dump up to first run
  588. while (x < r) {
  589. int len = r-x;
  590. if (len > 128) len = 128;
  591. stbiw__write_dump_data(s, len, &comp[x]);
  592. x += len;
  593. }
  594. // if there's a run, output it
  595. if (r+2 < width) { // same test as what we break out of in search loop, so only true if we break'd
  596. // find next byte after run
  597. while (r < width && comp[r] == comp[x])
  598. ++r;
  599. // output run up to r
  600. while (x < r) {
  601. int len = r-x;
  602. if (len > 127) len = 127;
  603. stbiw__write_run_data(s, len, comp[x]);
  604. x += len;
  605. }
  606. }
  607. }
  608. }
  609. }
  610. }
  611. static int stbi_write_hdr_core(stbi__write_context *s, int x, int y, int comp, float *data)
  612. {
  613. if (y <= 0 || x <= 0 || data == NULL)
  614. return 0;
  615. else {
  616. // Each component is stored separately. Allocate scratch space for full output scanline.
  617. unsigned char *scratch = (unsigned char *) STBIW_MALLOC(x*4);
  618. int i, len;
  619. char buffer[128];
  620. char header[] = "#?RADIANCE\n# Written by stb_image_write.h\nFORMAT=32-bit_rle_rgbe\n";
  621. s->func(s->context, header, sizeof(header)-1);
  622. #ifdef STBI_MSC_SECURE_CRT
  623. len = sprintf_s(buffer, "EXPOSURE= 1.0000000000000\n\n-Y %d +X %d\n", y, x);
  624. #else
  625. len = sprintf(buffer, "EXPOSURE= 1.0000000000000\n\n-Y %d +X %d\n", y, x);
  626. #endif
  627. s->func(s->context, buffer, len);
  628. for(i=0; i < y; i++)
  629. stbiw__write_hdr_scanline(s, x, comp, scratch, data + comp*x*(stbi__flip_vertically_on_write ? y-1-i : i));
  630. STBIW_FREE(scratch);
  631. return 1;
  632. }
  633. }
  634. STBIWDEF int stbi_write_hdr_to_func(stbi_write_func *func, void *context, int x, int y, int comp, const float *data)
  635. {
  636. stbi__write_context s;
  637. stbi__start_write_callbacks(&s, func, context);
  638. return stbi_write_hdr_core(&s, x, y, comp, (float *) data);
  639. }
  640. #ifndef STBI_WRITE_NO_STDIO
  641. STBIWDEF int stbi_write_hdr(char const *filename, int x, int y, int comp, const float *data)
  642. {
  643. stbi__write_context s;
  644. if (stbi__start_write_file(&s,filename)) {
  645. int r = stbi_write_hdr_core(&s, x, y, comp, (float *) data);
  646. stbi__end_write_file(&s);
  647. return r;
  648. } else
  649. return 0;
  650. }
  651. #endif // STBI_WRITE_NO_STDIO
  652. //////////////////////////////////////////////////////////////////////////////
  653. //
  654. // PNG writer
  655. //
  656. #ifndef STBIW_ZLIB_COMPRESS
  657. // stretchy buffer; stbiw__sbpush() == vector<>::push_back() -- stbiw__sbcount() == vector<>::size()
  658. #define stbiw__sbraw(a) ((int *) (a) - 2)
  659. #define stbiw__sbm(a) stbiw__sbraw(a)[0]
  660. #define stbiw__sbn(a) stbiw__sbraw(a)[1]
  661. #define stbiw__sbneedgrow(a,n) ((a)==0 || stbiw__sbn(a)+n >= stbiw__sbm(a))
  662. #define stbiw__sbmaybegrow(a,n) (stbiw__sbneedgrow(a,(n)) ? stbiw__sbgrow(a,n) : 0)
  663. #define stbiw__sbgrow(a,n) stbiw__sbgrowf((void **) &(a), (n), sizeof(*(a)))
  664. #define stbiw__sbpush(a, v) (stbiw__sbmaybegrow(a,1), (a)[stbiw__sbn(a)++] = (v))
  665. #define stbiw__sbcount(a) ((a) ? stbiw__sbn(a) : 0)
  666. #define stbiw__sbfree(a) ((a) ? STBIW_FREE(stbiw__sbraw(a)),0 : 0)
  667. static void *stbiw__sbgrowf(void **arr, int increment, int itemsize)
  668. {
  669. int m = *arr ? 2*stbiw__sbm(*arr)+increment : increment+1;
  670. void *p = STBIW_REALLOC_SIZED(*arr ? stbiw__sbraw(*arr) : 0, *arr ? (stbiw__sbm(*arr)*itemsize + sizeof(int)*2) : 0, itemsize * m + sizeof(int)*2);
  671. STBIW_ASSERT(p);
  672. if (p) {
  673. if (!*arr) ((int *) p)[1] = 0;
  674. *arr = (void *) ((int *) p + 2);
  675. stbiw__sbm(*arr) = m;
  676. }
  677. return *arr;
  678. }
  679. static unsigned char *stbiw__zlib_flushf(unsigned char *data, unsigned int *bitbuffer, int *bitcount)
  680. {
  681. while (*bitcount >= 8) {
  682. stbiw__sbpush(data, STBIW_UCHAR(*bitbuffer));
  683. *bitbuffer >>= 8;
  684. *bitcount -= 8;
  685. }
  686. return data;
  687. }
  688. static int stbiw__zlib_bitrev(int code, int codebits)
  689. {
  690. int res=0;
  691. while (codebits--) {
  692. res = (res << 1) | (code & 1);
  693. code >>= 1;
  694. }
  695. return res;
  696. }
  697. static unsigned int stbiw__zlib_countm(unsigned char *a, unsigned char *b, int limit)
  698. {
  699. int i;
  700. for (i=0; i < limit && i < 258; ++i)
  701. if (a[i] != b[i]) break;
  702. return i;
  703. }
  704. static unsigned int stbiw__zhash(unsigned char *data)
  705. {
  706. stbiw_uint32 hash = data[0] + (data[1] << 8) + (data[2] << 16);
  707. hash ^= hash << 3;
  708. hash += hash >> 5;
  709. hash ^= hash << 4;
  710. hash += hash >> 17;
  711. hash ^= hash << 25;
  712. hash += hash >> 6;
  713. return hash;
  714. }
  715. #define stbiw__zlib_flush() (out = stbiw__zlib_flushf(out, &bitbuf, &bitcount))
  716. #define stbiw__zlib_add(code,codebits) \
  717. (bitbuf |= (code) << bitcount, bitcount += (codebits), stbiw__zlib_flush())
  718. #define stbiw__zlib_huffa(b,c) stbiw__zlib_add(stbiw__zlib_bitrev(b,c),c)
  719. // default huffman tables
  720. #define stbiw__zlib_huff1(n) stbiw__zlib_huffa(0x30 + (n), 8)
  721. #define stbiw__zlib_huff2(n) stbiw__zlib_huffa(0x190 + (n)-144, 9)
  722. #define stbiw__zlib_huff3(n) stbiw__zlib_huffa(0 + (n)-256,7)
  723. #define stbiw__zlib_huff4(n) stbiw__zlib_huffa(0xc0 + (n)-280,8)
  724. #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))
  725. #define stbiw__zlib_huffb(n) ((n) <= 143 ? stbiw__zlib_huff1(n) : stbiw__zlib_huff2(n))
  726. #define stbiw__ZHASH 16384
  727. #endif // STBIW_ZLIB_COMPRESS
  728. STBIWDEF unsigned char * stbi_zlib_compress(unsigned char *data, int data_len, int *out_len, int quality)
  729. {
  730. #ifdef STBIW_ZLIB_COMPRESS
  731. // user provided a zlib compress implementation, use that
  732. return STBIW_ZLIB_COMPRESS(data, data_len, out_len, quality);
  733. #else // use builtin
  734. 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 };
  735. 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 };
  736. 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 };
  737. 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 };
  738. unsigned int bitbuf=0;
  739. int i,j, bitcount=0;
  740. unsigned char *out = NULL;
  741. unsigned char ***hash_table = (unsigned char***) STBIW_MALLOC(stbiw__ZHASH * sizeof(char**));
  742. if (hash_table == NULL)
  743. return NULL;
  744. if (quality < 5) quality = 5;
  745. stbiw__sbpush(out, 0x78); // DEFLATE 32K window
  746. stbiw__sbpush(out, 0x5e); // FLEVEL = 1
  747. stbiw__zlib_add(1,1); // BFINAL = 1
  748. stbiw__zlib_add(1,2); // BTYPE = 1 -- fixed huffman
  749. for (i=0; i < stbiw__ZHASH; ++i)
  750. hash_table[i] = NULL;
  751. i=0;
  752. while (i < data_len-3) {
  753. // hash next 3 bytes of data to be compressed
  754. int h = stbiw__zhash(data+i)&(stbiw__ZHASH-1), best=3;
  755. unsigned char *bestloc = 0;
  756. unsigned char **hlist = hash_table[h];
  757. int n = stbiw__sbcount(hlist);
  758. for (j=0; j < n; ++j) {
  759. if (hlist[j]-data > i-32768) { // if entry lies within window
  760. int d = stbiw__zlib_countm(hlist[j], data+i, data_len-i);
  761. if (d >= best) best=d,bestloc=hlist[j];
  762. }
  763. }
  764. // when hash table entry is too long, delete half the entries
  765. if (hash_table[h] && stbiw__sbn(hash_table[h]) == 2*quality) {
  766. STBIW_MEMMOVE(hash_table[h], hash_table[h]+quality, sizeof(hash_table[h][0])*quality);
  767. stbiw__sbn(hash_table[h]) = quality;
  768. }
  769. stbiw__sbpush(hash_table[h],data+i);
  770. if (bestloc) {
  771. // "lazy matching" - check match at *next* byte, and if it's better, do cur byte as literal
  772. h = stbiw__zhash(data+i+1)&(stbiw__ZHASH-1);
  773. hlist = hash_table[h];
  774. n = stbiw__sbcount(hlist);
  775. for (j=0; j < n; ++j) {
  776. if (hlist[j]-data > i-32767) {
  777. int e = stbiw__zlib_countm(hlist[j], data+i+1, data_len-i-1);
  778. if (e > best) { // if next match is better, bail on current match
  779. bestloc = NULL;
  780. break;
  781. }
  782. }
  783. }
  784. }
  785. if (bestloc) {
  786. int d = (int) (data+i - bestloc); // distance back
  787. STBIW_ASSERT(d <= 32767 && best <= 258);
  788. for (j=0; best > lengthc[j+1]-1; ++j);
  789. stbiw__zlib_huff(j+257);
  790. if (lengtheb[j]) stbiw__zlib_add(best - lengthc[j], lengtheb[j]);
  791. for (j=0; d > distc[j+1]-1; ++j);
  792. stbiw__zlib_add(stbiw__zlib_bitrev(j,5),5);
  793. if (disteb[j]) stbiw__zlib_add(d - distc[j], disteb[j]);
  794. i += best;
  795. } else {
  796. stbiw__zlib_huffb(data[i]);
  797. ++i;
  798. }
  799. }
  800. // write out final bytes
  801. for (;i < data_len; ++i)
  802. stbiw__zlib_huffb(data[i]);
  803. stbiw__zlib_huff(256); // end of block
  804. // pad with 0 bits to byte boundary
  805. while (bitcount)
  806. stbiw__zlib_add(0,1);
  807. for (i=0; i < stbiw__ZHASH; ++i)
  808. (void) stbiw__sbfree(hash_table[i]);
  809. STBIW_FREE(hash_table);
  810. {
  811. // compute adler32 on input
  812. unsigned int s1=1, s2=0;
  813. int blocklen = (int) (data_len % 5552);
  814. j=0;
  815. while (j < data_len) {
  816. for (i=0; i < blocklen; ++i) s1 += data[j+i], s2 += s1;
  817. s1 %= 65521, s2 %= 65521;
  818. j += blocklen;
  819. blocklen = 5552;
  820. }
  821. stbiw__sbpush(out, STBIW_UCHAR(s2 >> 8));
  822. stbiw__sbpush(out, STBIW_UCHAR(s2));
  823. stbiw__sbpush(out, STBIW_UCHAR(s1 >> 8));
  824. stbiw__sbpush(out, STBIW_UCHAR(s1));
  825. }
  826. *out_len = stbiw__sbn(out);
  827. // make returned pointer freeable
  828. STBIW_MEMMOVE(stbiw__sbraw(out), out, *out_len);
  829. return (unsigned char *) stbiw__sbraw(out);
  830. #endif // STBIW_ZLIB_COMPRESS
  831. }
  832. static unsigned int stbiw__crc32(unsigned char *buffer, int len)
  833. {
  834. #ifdef STBIW_CRC32
  835. return STBIW_CRC32(buffer, len);
  836. #else
  837. static unsigned int crc_table[256] =
  838. {
  839. 0x00000000, 0x77073096, 0xEE0E612C, 0x990951BA, 0x076DC419, 0x706AF48F, 0xE963A535, 0x9E6495A3,
  840. 0x0eDB8832, 0x79DCB8A4, 0xE0D5E91E, 0x97D2D988, 0x09B64C2B, 0x7EB17CBD, 0xE7B82D07, 0x90BF1D91,
  841. 0x1DB71064, 0x6AB020F2, 0xF3B97148, 0x84BE41DE, 0x1ADAD47D, 0x6DDDE4EB, 0xF4D4B551, 0x83D385C7,
  842. 0x136C9856, 0x646BA8C0, 0xFD62F97A, 0x8A65C9EC, 0x14015C4F, 0x63066CD9, 0xFA0F3D63, 0x8D080DF5,
  843. 0x3B6E20C8, 0x4C69105E, 0xD56041E4, 0xA2677172, 0x3C03E4D1, 0x4B04D447, 0xD20D85FD, 0xA50AB56B,
  844. 0x35B5A8FA, 0x42B2986C, 0xDBBBC9D6, 0xACBCF940, 0x32D86CE3, 0x45DF5C75, 0xDCD60DCF, 0xABD13D59,
  845. 0x26D930AC, 0x51DE003A, 0xC8D75180, 0xBFD06116, 0x21B4F4B5, 0x56B3C423, 0xCFBA9599, 0xB8BDA50F,
  846. 0x2802B89E, 0x5F058808, 0xC60CD9B2, 0xB10BE924, 0x2F6F7C87, 0x58684C11, 0xC1611DAB, 0xB6662D3D,
  847. 0x76DC4190, 0x01DB7106, 0x98D220BC, 0xEFD5102A, 0x71B18589, 0x06B6B51F, 0x9FBFE4A5, 0xE8B8D433,
  848. 0x7807C9A2, 0x0F00F934, 0x9609A88E, 0xE10E9818, 0x7F6A0DBB, 0x086D3D2D, 0x91646C97, 0xE6635C01,
  849. 0x6B6B51F4, 0x1C6C6162, 0x856530D8, 0xF262004E, 0x6C0695ED, 0x1B01A57B, 0x8208F4C1, 0xF50FC457,
  850. 0x65B0D9C6, 0x12B7E950, 0x8BBEB8EA, 0xFCB9887C, 0x62DD1DDF, 0x15DA2D49, 0x8CD37CF3, 0xFBD44C65,
  851. 0x4DB26158, 0x3AB551CE, 0xA3BC0074, 0xD4BB30E2, 0x4ADFA541, 0x3DD895D7, 0xA4D1C46D, 0xD3D6F4FB,
  852. 0x4369E96A, 0x346ED9FC, 0xAD678846, 0xDA60B8D0, 0x44042D73, 0x33031DE5, 0xAA0A4C5F, 0xDD0D7CC9,
  853. 0x5005713C, 0x270241AA, 0xBE0B1010, 0xC90C2086, 0x5768B525, 0x206F85B3, 0xB966D409, 0xCE61E49F,
  854. 0x5EDEF90E, 0x29D9C998, 0xB0D09822, 0xC7D7A8B4, 0x59B33D17, 0x2EB40D81, 0xB7BD5C3B, 0xC0BA6CAD,
  855. 0xEDB88320, 0x9ABFB3B6, 0x03B6E20C, 0x74B1D29A, 0xEAD54739, 0x9DD277AF, 0x04DB2615, 0x73DC1683,
  856. 0xE3630B12, 0x94643B84, 0x0D6D6A3E, 0x7A6A5AA8, 0xE40ECF0B, 0x9309FF9D, 0x0A00AE27, 0x7D079EB1,
  857. 0xF00F9344, 0x8708A3D2, 0x1E01F268, 0x6906C2FE, 0xF762575D, 0x806567CB, 0x196C3671, 0x6E6B06E7,
  858. 0xFED41B76, 0x89D32BE0, 0x10DA7A5A, 0x67DD4ACC, 0xF9B9DF6F, 0x8EBEEFF9, 0x17B7BE43, 0x60B08ED5,
  859. 0xD6D6A3E8, 0xA1D1937E, 0x38D8C2C4, 0x4FDFF252, 0xD1BB67F1, 0xA6BC5767, 0x3FB506DD, 0x48B2364B,
  860. 0xD80D2BDA, 0xAF0A1B4C, 0x36034AF6, 0x41047A60, 0xDF60EFC3, 0xA867DF55, 0x316E8EEF, 0x4669BE79,
  861. 0xCB61B38C, 0xBC66831A, 0x256FD2A0, 0x5268E236, 0xCC0C7795, 0xBB0B4703, 0x220216B9, 0x5505262F,
  862. 0xC5BA3BBE, 0xB2BD0B28, 0x2BB45A92, 0x5CB36A04, 0xC2D7FFA7, 0xB5D0CF31, 0x2CD99E8B, 0x5BDEAE1D,
  863. 0x9B64C2B0, 0xEC63F226, 0x756AA39C, 0x026D930A, 0x9C0906A9, 0xEB0E363F, 0x72076785, 0x05005713,
  864. 0x95BF4A82, 0xE2B87A14, 0x7BB12BAE, 0x0CB61B38, 0x92D28E9B, 0xE5D5BE0D, 0x7CDCEFB7, 0x0BDBDF21,
  865. 0x86D3D2D4, 0xF1D4E242, 0x68DDB3F8, 0x1FDA836E, 0x81BE16CD, 0xF6B9265B, 0x6FB077E1, 0x18B74777,
  866. 0x88085AE6, 0xFF0F6A70, 0x66063BCA, 0x11010B5C, 0x8F659EFF, 0xF862AE69, 0x616BFFD3, 0x166CCF45,
  867. 0xA00AE278, 0xD70DD2EE, 0x4E048354, 0x3903B3C2, 0xA7672661, 0xD06016F7, 0x4969474D, 0x3E6E77DB,
  868. 0xAED16A4A, 0xD9D65ADC, 0x40DF0B66, 0x37D83BF0, 0xA9BCAE53, 0xDEBB9EC5, 0x47B2CF7F, 0x30B5FFE9,
  869. 0xBDBDF21C, 0xCABAC28A, 0x53B39330, 0x24B4A3A6, 0xBAD03605, 0xCDD70693, 0x54DE5729, 0x23D967BF,
  870. 0xB3667A2E, 0xC4614AB8, 0x5D681B02, 0x2A6F2B94, 0xB40BBE37, 0xC30C8EA1, 0x5A05DF1B, 0x2D02EF8D
  871. };
  872. unsigned int crc = ~0u;
  873. int i;
  874. for (i=0; i < len; ++i)
  875. crc = (crc >> 8) ^ crc_table[buffer[i] ^ (crc & 0xff)];
  876. return ~crc;
  877. #endif
  878. }
  879. #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)
  880. #define stbiw__wp32(data,v) stbiw__wpng4(data, (v)>>24,(v)>>16,(v)>>8,(v));
  881. #define stbiw__wptag(data,s) stbiw__wpng4(data, s[0],s[1],s[2],s[3])
  882. static void stbiw__wpcrc(unsigned char **data, int len)
  883. {
  884. unsigned int crc = stbiw__crc32(*data - len - 4, len+4);
  885. stbiw__wp32(*data, crc);
  886. }
  887. static unsigned char stbiw__paeth(int a, int b, int c)
  888. {
  889. int p = a + b - c, pa = abs(p-a), pb = abs(p-b), pc = abs(p-c);
  890. if (pa <= pb && pa <= pc) return STBIW_UCHAR(a);
  891. if (pb <= pc) return STBIW_UCHAR(b);
  892. return STBIW_UCHAR(c);
  893. }
  894. // @OPTIMIZE: provide an option that always forces left-predict or paeth predict
  895. 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)
  896. {
  897. static int mapping[] = { 0,1,2,3,4 };
  898. static int firstmap[] = { 0,1,0,5,6 };
  899. int *mymap = (y != 0) ? mapping : firstmap;
  900. int i;
  901. int type = mymap[filter_type];
  902. unsigned char *z = pixels + stride_bytes * (stbi__flip_vertically_on_write ? height-1-y : y);
  903. int signed_stride = stbi__flip_vertically_on_write ? -stride_bytes : stride_bytes;
  904. if (type==0) {
  905. memcpy(line_buffer, z, width*n);
  906. return;
  907. }
  908. // first loop isn't optimized since it's just one pixel
  909. for (i = 0; i < n; ++i) {
  910. switch (type) {
  911. case 1: line_buffer[i] = z[i]; break;
  912. case 2: line_buffer[i] = z[i] - z[i-signed_stride]; break;
  913. case 3: line_buffer[i] = z[i] - (z[i-signed_stride]>>1); break;
  914. case 4: line_buffer[i] = (signed char) (z[i] - stbiw__paeth(0,z[i-signed_stride],0)); break;
  915. case 5: line_buffer[i] = z[i]; break;
  916. case 6: line_buffer[i] = z[i]; break;
  917. }
  918. }
  919. switch (type) {
  920. case 1: for (i=n; i < width*n; ++i) line_buffer[i] = z[i] - z[i-n]; break;
  921. case 2: for (i=n; i < width*n; ++i) line_buffer[i] = z[i] - z[i-signed_stride]; break;
  922. case 3: for (i=n; i < width*n; ++i) line_buffer[i] = z[i] - ((z[i-n] + z[i-signed_stride])>>1); break;
  923. 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;
  924. case 5: for (i=n; i < width*n; ++i) line_buffer[i] = z[i] - (z[i-n]>>1); break;
  925. case 6: for (i=n; i < width*n; ++i) line_buffer[i] = z[i] - stbiw__paeth(z[i-n], 0,0); break;
  926. }
  927. }
  928. STBIWDEF unsigned char *stbi_write_png_to_mem(const unsigned char *pixels, int stride_bytes, int x, int y, int n, int *out_len)
  929. {
  930. int force_filter = stbi_write_force_png_filter;
  931. int ctype[5] = { -1, 0, 4, 2, 6 };
  932. unsigned char sig[8] = { 137,80,78,71,13,10,26,10 };
  933. unsigned char *out,*o, *filt, *zlib;
  934. signed char *line_buffer;
  935. int j,zlen;
  936. if (stride_bytes == 0)
  937. stride_bytes = x * n;
  938. if (force_filter >= 5) {
  939. force_filter = -1;
  940. }
  941. filt = (unsigned char *) STBIW_MALLOC((x*n+1) * y); if (!filt) return 0;
  942. line_buffer = (signed char *) STBIW_MALLOC(x * n); if (!line_buffer) { STBIW_FREE(filt); return 0; }
  943. for (j=0; j < y; ++j) {
  944. int filter_type;
  945. if (force_filter > -1) {
  946. filter_type = force_filter;
  947. stbiw__encode_png_line((unsigned char*)(pixels), stride_bytes, x, y, j, n, force_filter, line_buffer);
  948. } else { // Estimate the best filter by running through all of them:
  949. int best_filter = 0, best_filter_val = 0x7fffffff, est, i;
  950. for (filter_type = 0; filter_type < 5; filter_type++) {
  951. stbiw__encode_png_line((unsigned char*)(pixels), stride_bytes, x, y, j, n, filter_type, line_buffer);
  952. // Estimate the entropy of the line using this filter; the less, the better.
  953. est = 0;
  954. for (i = 0; i < x*n; ++i) {
  955. est += abs((signed char) line_buffer[i]);
  956. }
  957. if (est < best_filter_val) {
  958. best_filter_val = est;
  959. best_filter = filter_type;
  960. }
  961. }
  962. if (filter_type != best_filter) { // If the last iteration already got us the best filter, don't redo it
  963. stbiw__encode_png_line((unsigned char*)(pixels), stride_bytes, x, y, j, n, best_filter, line_buffer);
  964. filter_type = best_filter;
  965. }
  966. }
  967. // when we get here, filter_type contains the filter type, and line_buffer contains the data
  968. filt[j*(x*n+1)] = (unsigned char) filter_type;
  969. STBIW_MEMMOVE(filt+j*(x*n+1)+1, line_buffer, x*n);
  970. }
  971. STBIW_FREE(line_buffer);
  972. zlib = stbi_zlib_compress(filt, y*( x*n+1), &zlen, stbi_write_png_compression_level);
  973. STBIW_FREE(filt);
  974. if (!zlib) return 0;
  975. // each tag requires 12 bytes of overhead
  976. out = (unsigned char *) STBIW_MALLOC(8 + 12+13 + 12+zlen + 12);
  977. if (!out) return 0;
  978. *out_len = 8 + 12+13 + 12+zlen + 12;
  979. o=out;
  980. STBIW_MEMMOVE(o,sig,8); o+= 8;
  981. stbiw__wp32(o, 13); // header length
  982. stbiw__wptag(o, "IHDR");
  983. stbiw__wp32(o, x);
  984. stbiw__wp32(o, y);
  985. *o++ = 8;
  986. *o++ = STBIW_UCHAR(ctype[n]);
  987. *o++ = 0;
  988. *o++ = 0;
  989. *o++ = 0;
  990. stbiw__wpcrc(&o,13);
  991. stbiw__wp32(o, zlen);
  992. stbiw__wptag(o, "IDAT");
  993. STBIW_MEMMOVE(o, zlib, zlen);
  994. o += zlen;
  995. STBIW_FREE(zlib);
  996. stbiw__wpcrc(&o, zlen);
  997. stbiw__wp32(o,0);
  998. stbiw__wptag(o, "IEND");
  999. stbiw__wpcrc(&o,0);
  1000. STBIW_ASSERT(o == out + *out_len);
  1001. return out;
  1002. }
  1003. #ifndef STBI_WRITE_NO_STDIO
  1004. STBIWDEF int stbi_write_png(char const *filename, int x, int y, int comp, const void *data, int stride_bytes)
  1005. {
  1006. FILE *f;
  1007. int len;
  1008. unsigned char *png = stbi_write_png_to_mem((const unsigned char *) data, stride_bytes, x, y, comp, &len);
  1009. if (png == NULL) return 0;
  1010. f = stbiw__fopen(filename, "wb");
  1011. if (!f) { STBIW_FREE(png); return 0; }
  1012. fwrite(png, 1, len, f);
  1013. fclose(f);
  1014. STBIW_FREE(png);
  1015. return 1;
  1016. }
  1017. #endif
  1018. 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)
  1019. {
  1020. int len;
  1021. unsigned char *png = stbi_write_png_to_mem((const unsigned char *) data, stride_bytes, x, y, comp, &len);
  1022. if (png == NULL) return 0;
  1023. func(context, png, len);
  1024. STBIW_FREE(png);
  1025. return 1;
  1026. }
  1027. /* ***************************************************************************
  1028. *
  1029. * JPEG writer
  1030. *
  1031. * This is based on Jon Olick's jo_jpeg.cpp:
  1032. * public domain Simple, Minimalistic JPEG writer - http://www.jonolick.com/code.html
  1033. */
  1034. 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,
  1035. 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 };
  1036. static void stbiw__jpg_writeBits(stbi__write_context *s, int *bitBufP, int *bitCntP, const unsigned short *bs) {
  1037. int bitBuf = *bitBufP, bitCnt = *bitCntP;
  1038. bitCnt += bs[1];
  1039. bitBuf |= bs[0] << (24 - bitCnt);
  1040. while(bitCnt >= 8) {
  1041. unsigned char c = (bitBuf >> 16) & 255;
  1042. stbiw__putc(s, c);
  1043. if(c == 255) {
  1044. stbiw__putc(s, 0);
  1045. }
  1046. bitBuf <<= 8;
  1047. bitCnt -= 8;
  1048. }
  1049. *bitBufP = bitBuf;
  1050. *bitCntP = bitCnt;
  1051. }
  1052. static void stbiw__jpg_DCT(float *d0p, float *d1p, float *d2p, float *d3p, float *d4p, float *d5p, float *d6p, float *d7p) {
  1053. float d0 = *d0p, d1 = *d1p, d2 = *d2p, d3 = *d3p, d4 = *d4p, d5 = *d5p, d6 = *d6p, d7 = *d7p;
  1054. float z1, z2, z3, z4, z5, z11, z13;
  1055. float tmp0 = d0 + d7;
  1056. float tmp7 = d0 - d7;
  1057. float tmp1 = d1 + d6;
  1058. float tmp6 = d1 - d6;
  1059. float tmp2 = d2 + d5;
  1060. float tmp5 = d2 - d5;
  1061. float tmp3 = d3 + d4;
  1062. float tmp4 = d3 - d4;
  1063. // Even part
  1064. float tmp10 = tmp0 + tmp3; // phase 2
  1065. float tmp13 = tmp0 - tmp3;
  1066. float tmp11 = tmp1 + tmp2;
  1067. float tmp12 = tmp1 - tmp2;
  1068. d0 = tmp10 + tmp11; // phase 3
  1069. d4 = tmp10 - tmp11;
  1070. z1 = (tmp12 + tmp13) * 0.707106781f; // c4
  1071. d2 = tmp13 + z1; // phase 5
  1072. d6 = tmp13 - z1;
  1073. // Odd part
  1074. tmp10 = tmp4 + tmp5; // phase 2
  1075. tmp11 = tmp5 + tmp6;
  1076. tmp12 = tmp6 + tmp7;
  1077. // The rotator is modified from fig 4-8 to avoid extra negations.
  1078. z5 = (tmp10 - tmp12) * 0.382683433f; // c6
  1079. z2 = tmp10 * 0.541196100f + z5; // c2-c6
  1080. z4 = tmp12 * 1.306562965f + z5; // c2+c6
  1081. z3 = tmp11 * 0.707106781f; // c4
  1082. z11 = tmp7 + z3; // phase 5
  1083. z13 = tmp7 - z3;
  1084. *d5p = z13 + z2; // phase 6
  1085. *d3p = z13 - z2;
  1086. *d1p = z11 + z4;
  1087. *d7p = z11 - z4;
  1088. *d0p = d0; *d2p = d2; *d4p = d4; *d6p = d6;
  1089. }
  1090. static void stbiw__jpg_calcBits(int val, unsigned short bits[2]) {
  1091. int tmp1 = val < 0 ? -val : val;
  1092. val = val < 0 ? val-1 : val;
  1093. bits[1] = 1;
  1094. while(tmp1 >>= 1) {
  1095. ++bits[1];
  1096. }
  1097. bits[0] = val & ((1<<bits[1])-1);
  1098. }
  1099. static int stbiw__jpg_processDU(stbi__write_context *s, int *bitBuf, int *bitCnt, float *CDU, float *fdtbl, int DC, const unsigned short HTDC[256][2], const unsigned short HTAC[256][2]) {
  1100. const unsigned short EOB[2] = { HTAC[0x00][0], HTAC[0x00][1] };
  1101. const unsigned short M16zeroes[2] = { HTAC[0xF0][0], HTAC[0xF0][1] };
  1102. int dataOff, i, diff, end0pos;
  1103. int DU[64];
  1104. // DCT rows
  1105. for(dataOff=0; dataOff<64; dataOff+=8) {
  1106. 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]);
  1107. }
  1108. // DCT columns
  1109. for(dataOff=0; dataOff<8; ++dataOff) {
  1110. stbiw__jpg_DCT(&CDU[dataOff], &CDU[dataOff+8], &CDU[dataOff+16], &CDU[dataOff+24], &CDU[dataOff+32], &CDU[dataOff+40], &CDU[dataOff+48], &CDU[dataOff+56]);
  1111. }
  1112. // Quantize/descale/zigzag the coefficients
  1113. for(i=0; i<64; ++i) {
  1114. float v = CDU[i]*fdtbl[i];
  1115. // DU[stbiw__jpg_ZigZag[i]] = (int)(v < 0 ? ceilf(v - 0.5f) : floorf(v + 0.5f));
  1116. // ceilf() and floorf() are C99, not C89, but I /think/ they're not needed here anyway?
  1117. DU[stbiw__jpg_ZigZag[i]] = (int)(v < 0 ? v - 0.5f : v + 0.5f);
  1118. }
  1119. // Encode DC
  1120. diff = DU[0] - DC;
  1121. if (diff == 0) {
  1122. stbiw__jpg_writeBits(s, bitBuf, bitCnt, HTDC[0]);
  1123. } else {
  1124. unsigned short bits[2];
  1125. stbiw__jpg_calcBits(diff, bits);
  1126. stbiw__jpg_writeBits(s, bitBuf, bitCnt, HTDC[bits[1]]);
  1127. stbiw__jpg_writeBits(s, bitBuf, bitCnt, bits);
  1128. }
  1129. // Encode ACs
  1130. end0pos = 63;
  1131. for(; (end0pos>0)&&(DU[end0pos]==0); --end0pos) {
  1132. }
  1133. // end0pos = first element in reverse order !=0
  1134. if(end0pos == 0) {
  1135. stbiw__jpg_writeBits(s, bitBuf, bitCnt, EOB);
  1136. return DU[0];
  1137. }
  1138. for(i = 1; i <= end0pos; ++i) {
  1139. int startpos = i;
  1140. int nrzeroes;
  1141. unsigned short bits[2];
  1142. for (; DU[i]==0 && i<=end0pos; ++i) {
  1143. }
  1144. nrzeroes = i-startpos;
  1145. if ( nrzeroes >= 16 ) {
  1146. int lng = nrzeroes>>4;
  1147. int nrmarker;
  1148. for (nrmarker=1; nrmarker <= lng; ++nrmarker)
  1149. stbiw__jpg_writeBits(s, bitBuf, bitCnt, M16zeroes);
  1150. nrzeroes &= 15;
  1151. }
  1152. stbiw__jpg_calcBits(DU[i], bits);
  1153. stbiw__jpg_writeBits(s, bitBuf, bitCnt, HTAC[(nrzeroes<<4)+bits[1]]);
  1154. stbiw__jpg_writeBits(s, bitBuf, bitCnt, bits);
  1155. }
  1156. if(end0pos != 63) {
  1157. stbiw__jpg_writeBits(s, bitBuf, bitCnt, EOB);
  1158. }
  1159. return DU[0];
  1160. }
  1161. static int stbi_write_jpg_core(stbi__write_context *s, int width, int height, int comp, const void* data, int quality) {
  1162. // Constants that don't pollute global namespace
  1163. 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};
  1164. static const unsigned char std_dc_luminance_values[] = {0,1,2,3,4,5,6,7,8,9,10,11};
  1165. 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};
  1166. static const unsigned char std_ac_luminance_values[] = {
  1167. 0x01,0x02,0x03,0x00,0x04,0x11,0x05,0x12,0x21,0x31,0x41,0x06,0x13,0x51,0x61,0x07,0x22,0x71,0x14,0x32,0x81,0x91,0xa1,0x08,
  1168. 0x23,0x42,0xb1,0xc1,0x15,0x52,0xd1,0xf0,0x24,0x33,0x62,0x72,0x82,0x09,0x0a,0x16,0x17,0x18,0x19,0x1a,0x25,0x26,0x27,0x28,
  1169. 0x29,0x2a,0x34,0x35,0x36,0x37,0x38,0x39,0x3a,0x43,0x44,0x45,0x46,0x47,0x48,0x49,0x4a,0x53,0x54,0x55,0x56,0x57,0x58,0x59,
  1170. 0x5a,0x63,0x64,0x65,0x66,0x67,0x68,0x69,0x6a,0x73,0x74,0x75,0x76,0x77,0x78,0x79,0x7a,0x83,0x84,0x85,0x86,0x87,0x88,0x89,
  1171. 0x8a,0x92,0x93,0x94,0x95,0x96,0x97,0x98,0x99,0x9a,0xa2,0xa3,0xa4,0xa5,0xa6,0xa7,0xa8,0xa9,0xaa,0xb2,0xb3,0xb4,0xb5,0xb6,
  1172. 0xb7,0xb8,0xb9,0xba,0xc2,0xc3,0xc4,0xc5,0xc6,0xc7,0xc8,0xc9,0xca,0xd2,0xd3,0xd4,0xd5,0xd6,0xd7,0xd8,0xd9,0xda,0xe1,0xe2,
  1173. 0xe3,0xe4,0xe5,0xe6,0xe7,0xe8,0xe9,0xea,0xf1,0xf2,0xf3,0xf4,0xf5,0xf6,0xf7,0xf8,0xf9,0xfa
  1174. };
  1175. 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};
  1176. static const unsigned char std_dc_chrominance_values[] = {0,1,2,3,4,5,6,7,8,9,10,11};
  1177. 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};
  1178. static const unsigned char std_ac_chrominance_values[] = {
  1179. 0x00,0x01,0x02,0x03,0x11,0x04,0x05,0x21,0x31,0x06,0x12,0x41,0x51,0x07,0x61,0x71,0x13,0x22,0x32,0x81,0x08,0x14,0x42,0x91,
  1180. 0xa1,0xb1,0xc1,0x09,0x23,0x33,0x52,0xf0,0x15,0x62,0x72,0xd1,0x0a,0x16,0x24,0x34,0xe1,0x25,0xf1,0x17,0x18,0x19,0x1a,0x26,
  1181. 0x27,0x28,0x29,0x2a,0x35,0x36,0x37,0x38,0x39,0x3a,0x43,0x44,0x45,0x46,0x47,0x48,0x49,0x4a,0x53,0x54,0x55,0x56,0x57,0x58,
  1182. 0x59,0x5a,0x63,0x64,0x65,0x66,0x67,0x68,0x69,0x6a,0x73,0x74,0x75,0x76,0x77,0x78,0x79,0x7a,0x82,0x83,0x84,0x85,0x86,0x87,
  1183. 0x88,0x89,0x8a,0x92,0x93,0x94,0x95,0x96,0x97,0x98,0x99,0x9a,0xa2,0xa3,0xa4,0xa5,0xa6,0xa7,0xa8,0xa9,0xaa,0xb2,0xb3,0xb4,
  1184. 0xb5,0xb6,0xb7,0xb8,0xb9,0xba,0xc2,0xc3,0xc4,0xc5,0xc6,0xc7,0xc8,0xc9,0xca,0xd2,0xd3,0xd4,0xd5,0xd6,0xd7,0xd8,0xd9,0xda,
  1185. 0xe2,0xe3,0xe4,0xe5,0xe6,0xe7,0xe8,0xe9,0xea,0xf2,0xf3,0xf4,0xf5,0xf6,0xf7,0xf8,0xf9,0xfa
  1186. };
  1187. // Huffman tables
  1188. 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}};
  1189. 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}};
  1190. static const unsigned short YAC_HT[256][2] = {
  1191. {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},
  1192. {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},
  1193. {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},
  1194. {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},
  1195. {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},
  1196. {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},
  1197. {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},
  1198. {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},
  1199. {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},
  1200. {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},
  1201. {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},
  1202. {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},
  1203. {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},
  1204. {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},
  1205. {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},
  1206. {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}
  1207. };
  1208. static const unsigned short UVAC_HT[256][2] = {
  1209. {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},
  1210. {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},
  1211. {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},
  1212. {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},
  1213. {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},
  1214. {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},
  1215. {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},
  1216. {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},
  1217. {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},
  1218. {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},
  1219. {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},
  1220. {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},
  1221. {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},
  1222. {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},
  1223. {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},
  1224. {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}
  1225. };
  1226. 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,
  1227. 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};
  1228. 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,
  1229. 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};
  1230. static const float aasf[] = { 1.0f * 2.828427125f, 1.387039845f * 2.828427125f, 1.306562965f * 2.828427125f, 1.175875602f * 2.828427125f,
  1231. 1.0f * 2.828427125f, 0.785694958f * 2.828427125f, 0.541196100f * 2.828427125f, 0.275899379f * 2.828427125f };
  1232. int row, col, i, k;
  1233. float fdtbl_Y[64], fdtbl_UV[64];
  1234. unsigned char YTable[64], UVTable[64];
  1235. if(!data || !width || !height || comp > 4 || comp < 1) {
  1236. return 0;
  1237. }
  1238. quality = quality ? quality : 90;
  1239. quality = quality < 1 ? 1 : quality > 100 ? 100 : quality;
  1240. quality = quality < 50 ? 5000 / quality : 200 - quality * 2;
  1241. for(i = 0; i < 64; ++i) {
  1242. int uvti, yti = (YQT[i]*quality+50)/100;
  1243. YTable[stbiw__jpg_ZigZag[i]] = (unsigned char) (yti < 1 ? 1 : yti > 255 ? 255 : yti);
  1244. uvti = (UVQT[i]*quality+50)/100;
  1245. UVTable[stbiw__jpg_ZigZag[i]] = (unsigned char) (uvti < 1 ? 1 : uvti > 255 ? 255 : uvti);
  1246. }
  1247. for(row = 0, k = 0; row < 8; ++row) {
  1248. for(col = 0; col < 8; ++col, ++k) {
  1249. fdtbl_Y[k] = 1 / (YTable [stbiw__jpg_ZigZag[k]] * aasf[row] * aasf[col]);
  1250. fdtbl_UV[k] = 1 / (UVTable[stbiw__jpg_ZigZag[k]] * aasf[row] * aasf[col]);
  1251. }
  1252. }
  1253. // Write Headers
  1254. {
  1255. 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 };
  1256. static const unsigned char head2[] = { 0xFF,0xDA,0,0xC,3,1,0,2,0x11,3,0x11,0,0x3F,0 };
  1257. const unsigned char head1[] = { 0xFF,0xC0,0,0x11,8,(unsigned char)(height>>8),STBIW_UCHAR(height),(unsigned char)(width>>8),STBIW_UCHAR(width),
  1258. 3,1,0x11,0,2,0x11,1,3,0x11,1,0xFF,0xC4,0x01,0xA2,0 };
  1259. s->func(s->context, (void*)head0, sizeof(head0));
  1260. s->func(s->context, (void*)YTable, sizeof(YTable));
  1261. stbiw__putc(s, 1);
  1262. s->func(s->context, UVTable, sizeof(UVTable));
  1263. s->func(s->context, (void*)head1, sizeof(head1));
  1264. s->func(s->context, (void*)(std_dc_luminance_nrcodes+1), sizeof(std_dc_luminance_nrcodes)-1);
  1265. s->func(s->context, (void*)std_dc_luminance_values, sizeof(std_dc_luminance_values));
  1266. stbiw__putc(s, 0x10); // HTYACinfo
  1267. s->func(s->context, (void*)(std_ac_luminance_nrcodes+1), sizeof(std_ac_luminance_nrcodes)-1);
  1268. s->func(s->context, (void*)std_ac_luminance_values, sizeof(std_ac_luminance_values));
  1269. stbiw__putc(s, 1); // HTUDCinfo
  1270. s->func(s->context, (void*)(std_dc_chrominance_nrcodes+1), sizeof(std_dc_chrominance_nrcodes)-1);
  1271. s->func(s->context, (void*)std_dc_chrominance_values, sizeof(std_dc_chrominance_values));
  1272. stbiw__putc(s, 0x11); // HTUACinfo
  1273. s->func(s->context, (void*)(std_ac_chrominance_nrcodes+1), sizeof(std_ac_chrominance_nrcodes)-1);
  1274. s->func(s->context, (void*)std_ac_chrominance_values, sizeof(std_ac_chrominance_values));
  1275. s->func(s->context, (void*)head2, sizeof(head2));
  1276. }
  1277. // Encode 8x8 macroblocks
  1278. {
  1279. static const unsigned short fillBits[] = {0x7F, 7};
  1280. const unsigned char *imageData = (const unsigned char *)data;
  1281. int DCY=0, DCU=0, DCV=0;
  1282. int bitBuf=0, bitCnt=0;
  1283. // comp == 2 is grey+alpha (alpha is ignored)
  1284. int ofsG = comp > 2 ? 1 : 0, ofsB = comp > 2 ? 2 : 0;
  1285. int x, y, pos;
  1286. for(y = 0; y < height; y += 8) {
  1287. for(x = 0; x < width; x += 8) {
  1288. float YDU[64], UDU[64], VDU[64];
  1289. for(row = y, pos = 0; row < y+8; ++row) {
  1290. int p;
  1291. if(row < height) {
  1292. p = (stbi__flip_vertically_on_write ? (height-1-row) : row)*width*comp;
  1293. } else {
  1294. // row >= height => use last input row (=> first if flipping)
  1295. p = stbi__flip_vertically_on_write ? 0 : ((height-1)*width*comp);
  1296. }
  1297. for(col = x; col < x+8; ++col, ++pos) {
  1298. float r, g, b;
  1299. // if col >= width => use pixel from last input column
  1300. p += ((col < width) ? col : (width-1))*comp;
  1301. r = imageData[p+0];
  1302. g = imageData[p+ofsG];
  1303. b = imageData[p+ofsB];
  1304. YDU[pos]=+0.29900f*r+0.58700f*g+0.11400f*b-128;
  1305. UDU[pos]=-0.16874f*r-0.33126f*g+0.50000f*b;
  1306. VDU[pos]=+0.50000f*r-0.41869f*g-0.08131f*b;
  1307. }
  1308. }
  1309. DCY = stbiw__jpg_processDU(s, &bitBuf, &bitCnt, YDU, fdtbl_Y, DCY, YDC_HT, YAC_HT);
  1310. DCU = stbiw__jpg_processDU(s, &bitBuf, &bitCnt, UDU, fdtbl_UV, DCU, UVDC_HT, UVAC_HT);
  1311. DCV = stbiw__jpg_processDU(s, &bitBuf, &bitCnt, VDU, fdtbl_UV, DCV, UVDC_HT, UVAC_HT);
  1312. }
  1313. }
  1314. // Do the bit alignment of the EOI marker
  1315. stbiw__jpg_writeBits(s, &bitBuf, &bitCnt, fillBits);
  1316. }
  1317. // EOI
  1318. stbiw__putc(s, 0xFF);
  1319. stbiw__putc(s, 0xD9);
  1320. return 1;
  1321. }
  1322. STBIWDEF int stbi_write_jpg_to_func(stbi_write_func *func, void *context, int x, int y, int comp, const void *data, int quality)
  1323. {
  1324. stbi__write_context s;
  1325. stbi__start_write_callbacks(&s, func, context);
  1326. return stbi_write_jpg_core(&s, x, y, comp, (void *) data, quality);
  1327. }
  1328. #ifndef STBI_WRITE_NO_STDIO
  1329. STBIWDEF int stbi_write_jpg(char const *filename, int x, int y, int comp, const void *data, int quality)
  1330. {
  1331. stbi__write_context s;
  1332. if (stbi__start_write_file(&s,filename)) {
  1333. int r = stbi_write_jpg_core(&s, x, y, comp, data, quality);
  1334. stbi__end_write_file(&s);
  1335. return r;
  1336. } else
  1337. return 0;
  1338. }
  1339. #endif
  1340. #endif // STB_IMAGE_WRITE_IMPLEMENTATION
  1341. /* Revision history
  1342. 1.10 (2019-02-07)
  1343. support utf8 filenames in Windows; fix warnings and platform ifdefs
  1344. 1.09 (2018-02-11)
  1345. fix typo in zlib quality API, improve STB_I_W_STATIC in C++
  1346. 1.08 (2018-01-29)
  1347. add stbi__flip_vertically_on_write, external zlib, zlib quality, choose PNG filter
  1348. 1.07 (2017-07-24)
  1349. doc fix
  1350. 1.06 (2017-07-23)
  1351. writing JPEG (using Jon Olick's code)
  1352. 1.05 ???
  1353. 1.04 (2017-03-03)
  1354. monochrome BMP expansion
  1355. 1.03 ???
  1356. 1.02 (2016-04-02)
  1357. avoid allocating large structures on the stack
  1358. 1.01 (2016-01-16)
  1359. STBIW_REALLOC_SIZED: support allocators with no realloc support
  1360. avoid race-condition in crc initialization
  1361. minor compile issues
  1362. 1.00 (2015-09-14)
  1363. installable file IO function
  1364. 0.99 (2015-09-13)
  1365. warning fixes; TGA rle support
  1366. 0.98 (2015-04-08)
  1367. added STBIW_MALLOC, STBIW_ASSERT etc
  1368. 0.97 (2015-01-18)
  1369. fixed HDR asserts, rewrote HDR rle logic
  1370. 0.96 (2015-01-17)
  1371. add HDR output
  1372. fix monochrome BMP
  1373. 0.95 (2014-08-17)
  1374. add monochrome TGA output
  1375. 0.94 (2014-05-31)
  1376. rename private functions to avoid conflicts with stb_image.h
  1377. 0.93 (2014-05-27)
  1378. warning fixes
  1379. 0.92 (2010-08-01)
  1380. casts to unsigned char to fix warnings
  1381. 0.91 (2010-07-17)
  1382. first public release
  1383. 0.90 first internal release
  1384. */
  1385. /*
  1386. ------------------------------------------------------------------------------
  1387. This software is available under 2 licenses -- choose whichever you prefer.
  1388. ------------------------------------------------------------------------------
  1389. ALTERNATIVE A - MIT License
  1390. Copyright (c) 2017 Sean Barrett
  1391. Permission is hereby granted, free of charge, to any person obtaining a copy of
  1392. this software and associated documentation files (the "Software"), to deal in
  1393. the Software without restriction, including without limitation the rights to
  1394. use, copy, modify, merge, publish, distribute, sublicense, and/or sell copies
  1395. of the Software, and to permit persons to whom the Software is furnished to do
  1396. so, subject to the following conditions:
  1397. The above copyright notice and this permission notice shall be included in all
  1398. copies or substantial portions of the Software.
  1399. THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR
  1400. IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY,
  1401. FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT. IN NO EVENT SHALL THE
  1402. AUTHORS OR COPYRIGHT HOLDERS BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER
  1403. LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING FROM,
  1404. OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN THE
  1405. SOFTWARE.
  1406. ------------------------------------------------------------------------------
  1407. ALTERNATIVE B - Public Domain (www.unlicense.org)
  1408. This is free and unencumbered software released into the public domain.
  1409. Anyone is free to copy, modify, publish, use, compile, sell, or distribute this
  1410. software, either in source code form or as a compiled binary, for any purpose,
  1411. commercial or non-commercial, and by any means.
  1412. In jurisdictions that recognize copyright laws, the author or authors of this
  1413. software dedicate any and all copyright interest in the software to the public
  1414. domain. We make this dedication for the benefit of the public at large and to
  1415. the detriment of our heirs and successors. We intend this dedication to be an
  1416. overt act of relinquishment in perpetuity of all present and future rights to
  1417. this software under copyright law.
  1418. THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR
  1419. IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY,
  1420. FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT. IN NO EVENT SHALL THE
  1421. AUTHORS BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER LIABILITY, WHETHER IN AN
  1422. ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING FROM, OUT OF OR IN CONNECTION
  1423. WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN THE SOFTWARE.
  1424. ------------------------------------------------------------------------------
  1425. */