source: trunk/src/3rdparty/libpng/pngwrite.c@ 451

Last change on this file since 451 was 2, checked in by Dmitry A. Kuminov, 16 years ago

Initially imported qt-all-opensource-src-4.5.1 from Trolltech.
File size: 48.0 KB
Line 
1
2/* pngwrite.c - general routines to write a PNG file
3 *
4 * Last changed in libpng 1.2.27 [April 29, 2008]
5 * For conditions of distribution and use, see copyright notice in png.h
6 * Copyright (c) 1998-2008 Glenn Randers-Pehrson
7 * (Version 0.96 Copyright (c) 1996, 1997 Andreas Dilger)
8 * (Version 0.88 Copyright (c) 1995, 1996 Guy Eric Schalnat, Group 42, Inc.)
9 */
10
11/* get internal access to png.h */
12#define PNG_INTERNAL
13#include "png.h"
14#ifdef PNG_WRITE_SUPPORTED
15
16/* Writes all the PNG information. This is the suggested way to use the
17 * library. If you have a new chunk to add, make a function to write it,
18 * and put it in the correct location here. If you want the chunk written
19 * after the image data, put it in png_write_end(). I strongly encourage
20 * you to supply a PNG_INFO_ flag, and check info_ptr->valid before writing
21 * the chunk, as that will keep the code from breaking if you want to just
22 * write a plain PNG file. If you have long comments, I suggest writing
23 * them in png_write_end(), and compressing them.
24 */
25void PNGAPI
26png_write_info_before_PLTE(png_structp png_ptr, png_infop info_ptr)
27{
28 png_debug(1, "in png_write_info_before_PLTE\n");
29 if (png_ptr == NULL || info_ptr == NULL)
30 return;
31 if (!(png_ptr->mode & PNG_WROTE_INFO_BEFORE_PLTE))
32 {
33 png_write_sig(png_ptr); /* write PNG signature */
34#if defined(PNG_MNG_FEATURES_SUPPORTED)
35 if((png_ptr->mode&PNG_HAVE_PNG_SIGNATURE)&&(png_ptr->mng_features_permitted))
36 {
37 png_warning(png_ptr,"MNG features are not allowed in a PNG datastream");
38 png_ptr->mng_features_permitted=0;
39 }
40#endif
41 /* write IHDR information. */
42 png_write_IHDR(png_ptr, info_ptr->width, info_ptr->height,
43 info_ptr->bit_depth, info_ptr->color_type, info_ptr->compression_type,
44 info_ptr->filter_type,
45#if defined(PNG_WRITE_INTERLACING_SUPPORTED)
46 info_ptr->interlace_type);
47#else
48 0);
49#endif
50 /* the rest of these check to see if the valid field has the appropriate
51 flag set, and if it does, writes the chunk. */
52#if defined(PNG_WRITE_gAMA_SUPPORTED)
53 if (info_ptr->valid & PNG_INFO_gAMA)
54 {
55# ifdef PNG_FLOATING_POINT_SUPPORTED
56 png_write_gAMA(png_ptr, info_ptr->gamma);
57#else
58#ifdef PNG_FIXED_POINT_SUPPORTED
59 png_write_gAMA_fixed(png_ptr, info_ptr->int_gamma);
60# endif
61#endif
62 }
63#endif
64#if defined(PNG_WRITE_sRGB_SUPPORTED)
65 if (info_ptr->valid & PNG_INFO_sRGB)
66 png_write_sRGB(png_ptr, (int)info_ptr->srgb_intent);
67#endif
68#if defined(PNG_WRITE_iCCP_SUPPORTED)
69 if (info_ptr->valid & PNG_INFO_iCCP)
70 png_write_iCCP(png_ptr, info_ptr->iccp_name, PNG_COMPRESSION_TYPE_BASE,
71 info_ptr->iccp_profile, (int)info_ptr->iccp_proflen);
72#endif
73#if defined(PNG_WRITE_sBIT_SUPPORTED)
74 if (info_ptr->valid & PNG_INFO_sBIT)
75 png_write_sBIT(png_ptr, &(info_ptr->sig_bit), info_ptr->color_type);
76#endif
77#if defined(PNG_WRITE_cHRM_SUPPORTED)
78 if (info_ptr->valid & PNG_INFO_cHRM)
79 {
80#ifdef PNG_FLOATING_POINT_SUPPORTED
81 png_write_cHRM(png_ptr,
82 info_ptr->x_white, info_ptr->y_white,
83 info_ptr->x_red, info_ptr->y_red,
84 info_ptr->x_green, info_ptr->y_green,
85 info_ptr->x_blue, info_ptr->y_blue);
86#else
87# ifdef PNG_FIXED_POINT_SUPPORTED
88 png_write_cHRM_fixed(png_ptr,
89 info_ptr->int_x_white, info_ptr->int_y_white,
90 info_ptr->int_x_red, info_ptr->int_y_red,
91 info_ptr->int_x_green, info_ptr->int_y_green,
92 info_ptr->int_x_blue, info_ptr->int_y_blue);
93# endif
94#endif
95 }
96#endif
97#if defined(PNG_WRITE_UNKNOWN_CHUNKS_SUPPORTED)
98 if (info_ptr->unknown_chunks_num)
99 {
100 png_unknown_chunk *up;
101
102 png_debug(5, "writing extra chunks\n");
103
104 for (up = info_ptr->unknown_chunks;
105 up < info_ptr->unknown_chunks + info_ptr->unknown_chunks_num;
106 up++)
107 {
108 int keep=png_handle_as_unknown(png_ptr, up->name);
109 if (keep != PNG_HANDLE_CHUNK_NEVER &&
110 up->location && !(up->location & PNG_HAVE_PLTE) &&
111 !(up->location & PNG_HAVE_IDAT) &&
112 ((up->name[3] & 0x20) || keep == PNG_HANDLE_CHUNK_ALWAYS ||
113 (png_ptr->flags & PNG_FLAG_KEEP_UNSAFE_CHUNKS)))
114 {
115 if (up->size == 0)
116 png_warning(png_ptr, "Writing zero-length unknown chunk");
117 png_write_chunk(png_ptr, up->name, up->data, up->size);
118 }
119 }
120 }
121#endif
122 png_ptr->mode |= PNG_WROTE_INFO_BEFORE_PLTE;
123 }
124}
125
126void PNGAPI
127png_write_info(png_structp png_ptr, png_infop info_ptr)
128{
129#if defined(PNG_WRITE_TEXT_SUPPORTED) || defined(PNG_WRITE_sPLT_SUPPORTED)
130 int i;
131#endif
132
133 png_debug(1, "in png_write_info\n");
134
135 if (png_ptr == NULL || info_ptr == NULL)
136 return;
137
138 png_write_info_before_PLTE(png_ptr, info_ptr);
139
140 if (info_ptr->valid & PNG_INFO_PLTE)
141 png_write_PLTE(png_ptr, info_ptr->palette,
142 (png_uint_32)info_ptr->num_palette);
143 else if (info_ptr->color_type == PNG_COLOR_TYPE_PALETTE)
144 png_error(png_ptr, "Valid palette required for paletted images");
145
146#if defined(PNG_WRITE_tRNS_SUPPORTED)
147 if (info_ptr->valid & PNG_INFO_tRNS)
148 {
149#if defined(PNG_WRITE_INVERT_ALPHA_SUPPORTED)
150 /* invert the alpha channel (in tRNS) */
151 if ((png_ptr->transformations & PNG_INVERT_ALPHA) &&
152 info_ptr->color_type == PNG_COLOR_TYPE_PALETTE)
153 {
154 int j;
155 for (j=0; j<(int)info_ptr->num_trans; j++)
156 info_ptr->trans[j] = (png_byte)(255 - info_ptr->trans[j]);
157 }
158#endif
159 png_write_tRNS(png_ptr, info_ptr->trans, &(info_ptr->trans_values),
160 info_ptr->num_trans, info_ptr->color_type);
161 }
162#endif
163#if defined(PNG_WRITE_bKGD_SUPPORTED)
164 if (info_ptr->valid & PNG_INFO_bKGD)
165 png_write_bKGD(png_ptr, &(info_ptr->background), info_ptr->color_type);
166#endif
167#if defined(PNG_WRITE_hIST_SUPPORTED)
168 if (info_ptr->valid & PNG_INFO_hIST)
169 png_write_hIST(png_ptr, info_ptr->hist, info_ptr->num_palette);
170#endif
171#if defined(PNG_WRITE_oFFs_SUPPORTED)
172 if (info_ptr->valid & PNG_INFO_oFFs)
173 png_write_oFFs(png_ptr, info_ptr->x_offset, info_ptr->y_offset,
174 info_ptr->offset_unit_type);
175#endif
176#if defined(PNG_WRITE_pCAL_SUPPORTED)
177 if (info_ptr->valid & PNG_INFO_pCAL)
178 png_write_pCAL(png_ptr, info_ptr->pcal_purpose, info_ptr->pcal_X0,
179 info_ptr->pcal_X1, info_ptr->pcal_type, info_ptr->pcal_nparams,
180 info_ptr->pcal_units, info_ptr->pcal_params);
181#endif
182#if defined(PNG_WRITE_sCAL_SUPPORTED)
183 if (info_ptr->valid & PNG_INFO_sCAL)
184#if defined(PNG_FLOATING_POINT_SUPPORTED) && !defined(PNG_NO_STDIO)
185 png_write_sCAL(png_ptr, (int)info_ptr->scal_unit,
186 info_ptr->scal_pixel_width, info_ptr->scal_pixel_height);
187#else
188#ifdef PNG_FIXED_POINT_SUPPORTED
189 png_write_sCAL_s(png_ptr, (int)info_ptr->scal_unit,
190 info_ptr->scal_s_width, info_ptr->scal_s_height);
191#else
192 png_warning(png_ptr,
193 "png_write_sCAL not supported; sCAL chunk not written.");
194#endif
195#endif
196#endif
197#if defined(PNG_WRITE_pHYs_SUPPORTED)
198 if (info_ptr->valid & PNG_INFO_pHYs)
199 png_write_pHYs(png_ptr, info_ptr->x_pixels_per_unit,
200 info_ptr->y_pixels_per_unit, info_ptr->phys_unit_type);
201#endif
202#if defined(PNG_WRITE_tIME_SUPPORTED)
203 if (info_ptr->valid & PNG_INFO_tIME)
204 {
205 png_write_tIME(png_ptr, &(info_ptr->mod_time));
206 png_ptr->mode |= PNG_WROTE_tIME;
207 }
208#endif
209#if defined(PNG_WRITE_sPLT_SUPPORTED)
210 if (info_ptr->valid & PNG_INFO_sPLT)
211 for (i = 0; i < (int)info_ptr->splt_palettes_num; i++)
212 png_write_sPLT(png_ptr, info_ptr->splt_palettes + i);
213#endif
214#if defined(PNG_WRITE_TEXT_SUPPORTED)
215 /* Check to see if we need to write text chunks */
216 for (i = 0; i < info_ptr->num_text; i++)
217 {
218 png_debug2(2, "Writing header text chunk %d, type %d\n", i,
219 info_ptr->text[i].compression);
220 /* an internationalized chunk? */
221 if (info_ptr->text[i].compression > 0)
222 {
223#if defined(PNG_WRITE_iTXt_SUPPORTED)
224 /* write international chunk */
225 png_write_iTXt(png_ptr,
226 info_ptr->text[i].compression,
227 info_ptr->text[i].key,
228 info_ptr->text[i].lang,
229 info_ptr->text[i].lang_key,
230 info_ptr->text[i].text);
231#else
232 png_warning(png_ptr, "Unable to write international text");
233#endif
234 /* Mark this chunk as written */
235 info_ptr->text[i].compression = PNG_TEXT_COMPRESSION_NONE_WR;
236 }
237 /* If we want a compressed text chunk */
238 else if (info_ptr->text[i].compression == PNG_TEXT_COMPRESSION_zTXt)
239 {
240#if defined(PNG_WRITE_zTXt_SUPPORTED)
241 /* write compressed chunk */
242 png_write_zTXt(png_ptr, info_ptr->text[i].key,
243 info_ptr->text[i].text, 0,
244 info_ptr->text[i].compression);
245#else
246 png_warning(png_ptr, "Unable to write compressed text");
247#endif
248 /* Mark this chunk as written */
249 info_ptr->text[i].compression = PNG_TEXT_COMPRESSION_zTXt_WR;
250 }
251 else if (info_ptr->text[i].compression == PNG_TEXT_COMPRESSION_NONE)
252 {
253#if defined(PNG_WRITE_tEXt_SUPPORTED)
254 /* write uncompressed chunk */
255 png_write_tEXt(png_ptr, info_ptr->text[i].key,
256 info_ptr->text[i].text,
257 0);
258#else
259 png_warning(png_ptr, "Unable to write uncompressed text");
260#endif
261 /* Mark this chunk as written */
262 info_ptr->text[i].compression = PNG_TEXT_COMPRESSION_NONE_WR;
263 }
264 }
265#endif
266#if defined(PNG_WRITE_UNKNOWN_CHUNKS_SUPPORTED)
267 if (info_ptr->unknown_chunks_num)
268 {
269 png_unknown_chunk *up;
270
271 png_debug(5, "writing extra chunks\n");
272
273 for (up = info_ptr->unknown_chunks;
274 up < info_ptr->unknown_chunks + info_ptr->unknown_chunks_num;
275 up++)
276 {
277 int keep=png_handle_as_unknown(png_ptr, up->name);
278 if (keep != PNG_HANDLE_CHUNK_NEVER &&
279 up->location && (up->location & PNG_HAVE_PLTE) &&
280 !(up->location & PNG_HAVE_IDAT) &&
281 ((up->name[3] & 0x20) || keep == PNG_HANDLE_CHUNK_ALWAYS ||
282 (png_ptr->flags & PNG_FLAG_KEEP_UNSAFE_CHUNKS)))
283 {
284 png_write_chunk(png_ptr, up->name, up->data, up->size);
285 }
286 }
287 }
288#endif
289}
290
291/* Writes the end of the PNG file. If you don't want to write comments or
292 * time information, you can pass NULL for info. If you already wrote these
293 * in png_write_info(), do not write them again here. If you have long
294 * comments, I suggest writing them here, and compressing them.
295 */
296void PNGAPI
297png_write_end(png_structp png_ptr, png_infop info_ptr)
298{
299 png_debug(1, "in png_write_end\n");
300 if (png_ptr == NULL)
301 return;
302 if (!(png_ptr->mode & PNG_HAVE_IDAT))
303 png_error(png_ptr, "No IDATs written into file");
304
305 /* see if user wants us to write information chunks */
306 if (info_ptr != NULL)
307 {
308#if defined(PNG_WRITE_TEXT_SUPPORTED)
309 int i; /* local index variable */
310#endif
311#if defined(PNG_WRITE_tIME_SUPPORTED)
312 /* check to see if user has supplied a time chunk */
313 if ((info_ptr->valid & PNG_INFO_tIME) &&
314 !(png_ptr->mode & PNG_WROTE_tIME))
315 png_write_tIME(png_ptr, &(info_ptr->mod_time));
316#endif
317#if defined(PNG_WRITE_TEXT_SUPPORTED)
318 /* loop through comment chunks */
319 for (i = 0; i < info_ptr->num_text; i++)
320 {
321 png_debug2(2, "Writing trailer text chunk %d, type %d\n", i,
322 info_ptr->text[i].compression);
323 /* an internationalized chunk? */
324 if (info_ptr->text[i].compression > 0)
325 {
326#if defined(PNG_WRITE_iTXt_SUPPORTED)
327 /* write international chunk */
328 png_write_iTXt(png_ptr,
329 info_ptr->text[i].compression,
330 info_ptr->text[i].key,
331 info_ptr->text[i].lang,
332 info_ptr->text[i].lang_key,
333 info_ptr->text[i].text);
334#else
335 png_warning(png_ptr, "Unable to write international text");
336#endif
337 /* Mark this chunk as written */
338 info_ptr->text[i].compression = PNG_TEXT_COMPRESSION_NONE_WR;
339 }
340 else if (info_ptr->text[i].compression >= PNG_TEXT_COMPRESSION_zTXt)
341 {
342#if defined(PNG_WRITE_zTXt_SUPPORTED)
343 /* write compressed chunk */
344 png_write_zTXt(png_ptr, info_ptr->text[i].key,
345 info_ptr->text[i].text, 0,
346 info_ptr->text[i].compression);
347#else
348 png_warning(png_ptr, "Unable to write compressed text");
349#endif
350 /* Mark this chunk as written */
351 info_ptr->text[i].compression = PNG_TEXT_COMPRESSION_zTXt_WR;
352 }
353 else if (info_ptr->text[i].compression == PNG_TEXT_COMPRESSION_NONE)
354 {
355#if defined(PNG_WRITE_tEXt_SUPPORTED)
356 /* write uncompressed chunk */
357 png_write_tEXt(png_ptr, info_ptr->text[i].key,
358 info_ptr->text[i].text, 0);
359#else
360 png_warning(png_ptr, "Unable to write uncompressed text");
361#endif
362
363 /* Mark this chunk as written */
364 info_ptr->text[i].compression = PNG_TEXT_COMPRESSION_NONE_WR;
365 }
366 }
367#endif
368#if defined(PNG_WRITE_UNKNOWN_CHUNKS_SUPPORTED)
369 if (info_ptr->unknown_chunks_num)
370 {
371 png_unknown_chunk *up;
372
373 png_debug(5, "writing extra chunks\n");
374
375 for (up = info_ptr->unknown_chunks;
376 up < info_ptr->unknown_chunks + info_ptr->unknown_chunks_num;
377 up++)
378 {
379 int keep=png_handle_as_unknown(png_ptr, up->name);
380 if (keep != PNG_HANDLE_CHUNK_NEVER &&
381 up->location && (up->location & PNG_AFTER_IDAT) &&
382 ((up->name[3] & 0x20) || keep == PNG_HANDLE_CHUNK_ALWAYS ||
383 (png_ptr->flags & PNG_FLAG_KEEP_UNSAFE_CHUNKS)))
384 {
385 png_write_chunk(png_ptr, up->name, up->data, up->size);
386 }
387 }
388 }
389#endif
390 }
391
392 png_ptr->mode |= PNG_AFTER_IDAT;
393
394 /* write end of PNG file */
395 png_write_IEND(png_ptr);
396}
397
398#if defined(PNG_WRITE_tIME_SUPPORTED)
399#if !defined(_WIN32_WCE)
400/* "time.h" functions are not supported on WindowsCE */
401void PNGAPI
402png_convert_from_struct_tm(png_timep ptime, struct tm FAR * ttime)
403{
404 png_debug(1, "in png_convert_from_struct_tm\n");
405 ptime->year = (png_uint_16)(1900 + ttime->tm_year);
406 ptime->month = (png_byte)(ttime->tm_mon + 1);
407 ptime->day = (png_byte)ttime->tm_mday;
408 ptime->hour = (png_byte)ttime->tm_hour;
409 ptime->minute = (png_byte)ttime->tm_min;
410 ptime->second = (png_byte)ttime->tm_sec;
411}
412
413void PNGAPI
414png_convert_from_time_t(png_timep ptime, time_t ttime)
415{
416 struct tm *tbuf;
417
418 png_debug(1, "in png_convert_from_time_t\n");
419 tbuf = gmtime(&ttime);
420 png_convert_from_struct_tm(ptime, tbuf);
421}
422#endif
423#endif
424
425/* Initialize png_ptr structure, and allocate any memory needed */
426png_structp PNGAPI
427png_create_write_struct(png_const_charp user_png_ver, png_voidp error_ptr,
428 png_error_ptr error_fn, png_error_ptr warn_fn)
429{
430#ifdef PNG_USER_MEM_SUPPORTED
431 return (png_create_write_struct_2(user_png_ver, error_ptr, error_fn,
432 warn_fn, png_voidp_NULL, png_malloc_ptr_NULL, png_free_ptr_NULL));
433}
434
435/* Alternate initialize png_ptr structure, and allocate any memory needed */
436png_structp PNGAPI
437png_create_write_struct_2(png_const_charp user_png_ver, png_voidp error_ptr,
438 png_error_ptr error_fn, png_error_ptr warn_fn, png_voidp mem_ptr,
439 png_malloc_ptr malloc_fn, png_free_ptr free_fn)
440{
441#endif /* PNG_USER_MEM_SUPPORTED */
442 png_structp png_ptr;
443#ifdef PNG_SETJMP_SUPPORTED
444#ifdef USE_FAR_KEYWORD
445 jmp_buf jmpbuf;
446#endif
447#endif
448 int i;
449 png_debug(1, "in png_create_write_struct\n");
450#ifdef PNG_USER_MEM_SUPPORTED
451 png_ptr = (png_structp)png_create_struct_2(PNG_STRUCT_PNG,
452 (png_malloc_ptr)malloc_fn, (png_voidp)mem_ptr);
453#else
454 png_ptr = (png_structp)png_create_struct(PNG_STRUCT_PNG);
455#endif /* PNG_USER_MEM_SUPPORTED */
456 if (png_ptr == NULL)
457 return (NULL);
458
459 /* added at libpng-1.2.6 */
460#ifdef PNG_SET_USER_LIMITS_SUPPORTED
461 png_ptr->user_width_max=PNG_USER_WIDTH_MAX;
462 png_ptr->user_height_max=PNG_USER_HEIGHT_MAX;
463#endif
464
465#ifdef PNG_SETJMP_SUPPORTED
466#ifdef USE_FAR_KEYWORD
467 if (setjmp(jmpbuf))
468#else
469 if (setjmp(png_ptr->jmpbuf))
470#endif
471 {
472 png_free(png_ptr, png_ptr->zbuf);
473 png_ptr->zbuf=NULL;
474 png_destroy_struct(png_ptr);
475 return (NULL);
476 }
477#ifdef USE_FAR_KEYWORD
478 png_memcpy(png_ptr->jmpbuf,jmpbuf,png_sizeof(jmp_buf));
479#endif
480#endif
481
482#ifdef PNG_USER_MEM_SUPPORTED
483 png_set_mem_fn(png_ptr, mem_ptr, malloc_fn, free_fn);
484#endif /* PNG_USER_MEM_SUPPORTED */
485 png_set_error_fn(png_ptr, error_ptr, error_fn, warn_fn);
486
487 if(user_png_ver)
488 {
489 i=0;
490 do
491 {
492 if(user_png_ver[i] != png_libpng_ver[i])
493 png_ptr->flags |= PNG_FLAG_LIBRARY_MISMATCH;
494 } while (png_libpng_ver[i++]);
495 }
496
497 if (png_ptr->flags & PNG_FLAG_LIBRARY_MISMATCH)
498 {
499 /* Libpng 0.90 and later are binary incompatible with libpng 0.89, so
500 * we must recompile any applications that use any older library version.
501 * For versions after libpng 1.0, we will be compatible, so we need
502 * only check the first digit.
503 */
504 if (user_png_ver == NULL || user_png_ver[0] != png_libpng_ver[0] ||
505 (user_png_ver[0] == '1' && user_png_ver[2] != png_libpng_ver[2]) ||
506 (user_png_ver[0] == '0' && user_png_ver[2] < '9'))
507 {
508#if !defined(PNG_NO_STDIO) && !defined(_WIN32_WCE)
509 char msg[80];
510 if (user_png_ver)
511 {
512 png_snprintf(msg, 80,
513 "Application was compiled with png.h from libpng-%.20s",
514 user_png_ver);
515 png_warning(png_ptr, msg);
516 }
517 png_snprintf(msg, 80,
518 "Application is running with png.c from libpng-%.20s",
519 png_libpng_ver);
520 png_warning(png_ptr, msg);
521#endif
522#ifdef PNG_ERROR_NUMBERS_SUPPORTED
523 png_ptr->flags=0;
524#endif
525 png_error(png_ptr,
526 "Incompatible libpng version in application and library");
527 }
528 }
529
530 /* initialize zbuf - compression buffer */
531 png_ptr->zbuf_size = PNG_ZBUF_SIZE;
532 png_ptr->zbuf = (png_bytep)png_malloc(png_ptr,
533 (png_uint_32)png_ptr->zbuf_size);
534
535 png_set_write_fn(png_ptr, png_voidp_NULL, png_rw_ptr_NULL,
536 png_flush_ptr_NULL);
537
538#if defined(PNG_WRITE_WEIGHTED_FILTER_SUPPORTED)
539 png_set_filter_heuristics(png_ptr, PNG_FILTER_HEURISTIC_DEFAULT,
540 1, png_doublep_NULL, png_doublep_NULL);
541#endif
542
543#ifdef PNG_SETJMP_SUPPORTED
544/* Applications that neglect to set up their own setjmp() and then encounter
545 a png_error() will longjmp here. Since the jmpbuf is then meaningless we
546 abort instead of returning. */
547#ifdef USE_FAR_KEYWORD
548 if (setjmp(jmpbuf))
549 PNG_ABORT();
550 png_memcpy(png_ptr->jmpbuf,jmpbuf,png_sizeof(jmp_buf));
551#else
552 if (setjmp(png_ptr->jmpbuf))
553 PNG_ABORT();
554#endif
555#endif
556 return (png_ptr);
557}
558
559/* Initialize png_ptr structure, and allocate any memory needed */
560#if defined(PNG_1_0_X) || defined(PNG_1_2_X)
561/* Deprecated. */
562#undef png_write_init
563void PNGAPI
564png_write_init(png_structp png_ptr)
565{
566 /* We only come here via pre-1.0.7-compiled applications */
567 png_write_init_2(png_ptr, "1.0.6 or earlier", 0, 0);
568}
569
570void PNGAPI
571png_write_init_2(png_structp png_ptr, png_const_charp user_png_ver,
572 png_size_t png_struct_size, png_size_t png_info_size)
573{
574 /* We only come here via pre-1.0.12-compiled applications */
575 if(png_ptr == NULL) return;
576#if !defined(PNG_NO_STDIO) && !defined(_WIN32_WCE)
577 if(png_sizeof(png_struct) > png_struct_size ||
578 png_sizeof(png_info) > png_info_size)
579 {
580 char msg[80];
581 png_ptr->warning_fn=NULL;
582 if (user_png_ver)
583 {
584 png_snprintf(msg, 80,
585 "Application was compiled with png.h from libpng-%.20s",
586 user_png_ver);
587 png_warning(png_ptr, msg);
588 }
589 png_snprintf(msg, 80,
590 "Application is running with png.c from libpng-%.20s",
591 png_libpng_ver);
592 png_warning(png_ptr, msg);
593 }
594#endif
595 if(png_sizeof(png_struct) > png_struct_size)
596 {
597 png_ptr->error_fn=NULL;
598#ifdef PNG_ERROR_NUMBERS_SUPPORTED
599 png_ptr->flags=0;
600#endif
601 png_error(png_ptr,
602 "The png struct allocated by the application for writing is too small.");
603 }
604 if(png_sizeof(png_info) > png_info_size)
605 {
606 png_ptr->error_fn=NULL;
607#ifdef PNG_ERROR_NUMBERS_SUPPORTED
608 png_ptr->flags=0;
609#endif
610 png_error(png_ptr,
611 "The info struct allocated by the application for writing is too small.");
612 }
613 png_write_init_3(&png_ptr, user_png_ver, png_struct_size);
614}
615#endif /* PNG_1_0_X || PNG_1_2_X */
616
617
618void PNGAPI
619png_write_init_3(png_structpp ptr_ptr, png_const_charp user_png_ver,
620 png_size_t png_struct_size)
621{
622 png_structp png_ptr=*ptr_ptr;
623#ifdef PNG_SETJMP_SUPPORTED
624 jmp_buf tmp_jmp; /* to save current jump buffer */
625#endif
626
627 int i = 0;
628
629 if (png_ptr == NULL)
630 return;
631
632 do
633 {
634 if (user_png_ver[i] != png_libpng_ver[i])
635 {
636#ifdef PNG_LEGACY_SUPPORTED
637 png_ptr->flags |= PNG_FLAG_LIBRARY_MISMATCH;
638#else
639 png_ptr->warning_fn=NULL;
640 png_warning(png_ptr,
641 "Application uses deprecated png_write_init() and should be recompiled.");
642 break;
643#endif
644 }
645 } while (png_libpng_ver[i++]);
646
647 png_debug(1, "in png_write_init_3\n");
648
649#ifdef PNG_SETJMP_SUPPORTED
650 /* save jump buffer and error functions */
651 png_memcpy(tmp_jmp, png_ptr->jmpbuf, png_sizeof (jmp_buf));
652#endif
653
654 if (png_sizeof(png_struct) > png_struct_size)
655 {
656 png_destroy_struct(png_ptr);
657 png_ptr = (png_structp)png_create_struct(PNG_STRUCT_PNG);
658 *ptr_ptr = png_ptr;
659 }
660
661 /* reset all variables to 0 */
662 png_memset(png_ptr, 0, png_sizeof (png_struct));
663
664 /* added at libpng-1.2.6 */
665#ifdef PNG_SET_USER_LIMITS_SUPPORTED
666 png_ptr->user_width_max=PNG_USER_WIDTH_MAX;
667 png_ptr->user_height_max=PNG_USER_HEIGHT_MAX;
668#endif
669
670#ifdef PNG_SETJMP_SUPPORTED
671 /* restore jump buffer */
672 png_memcpy(png_ptr->jmpbuf, tmp_jmp, png_sizeof (jmp_buf));
673#endif
674
675 png_set_write_fn(png_ptr, png_voidp_NULL, png_rw_ptr_NULL,
676 png_flush_ptr_NULL);
677
678 /* initialize zbuf - compression buffer */
679 png_ptr->zbuf_size = PNG_ZBUF_SIZE;
680 png_ptr->zbuf = (png_bytep)png_malloc(png_ptr,
681 (png_uint_32)png_ptr->zbuf_size);
682
683#if defined(PNG_WRITE_WEIGHTED_FILTER_SUPPORTED)
684 png_set_filter_heuristics(png_ptr, PNG_FILTER_HEURISTIC_DEFAULT,
685 1, png_doublep_NULL, png_doublep_NULL);
686#endif
687}
688
689/* Write a few rows of image data. If the image is interlaced,
690 * either you will have to write the 7 sub images, or, if you
691 * have called png_set_interlace_handling(), you will have to
692 * "write" the image seven times.
693 */
694void PNGAPI
695png_write_rows(png_structp png_ptr, png_bytepp row,
696 png_uint_32 num_rows)
697{
698 png_uint_32 i; /* row counter */
699 png_bytepp rp; /* row pointer */
700
701 png_debug(1, "in png_write_rows\n");
702
703 if (png_ptr == NULL)
704 return;
705
706 /* loop through the rows */
707 for (i = 0, rp = row; i < num_rows; i++, rp++)
708 {
709 png_write_row(png_ptr, *rp);
710 }
711}
712
713/* Write the image. You only need to call this function once, even
714 * if you are writing an interlaced image.
715 */
716void PNGAPI
717png_write_image(png_structp png_ptr, png_bytepp image)
718{
719 png_uint_32 i; /* row index */
720 int pass, num_pass; /* pass variables */
721 png_bytepp rp; /* points to current row */
722
723 if (png_ptr == NULL)
724 return;
725
726 png_debug(1, "in png_write_image\n");
727#if defined(PNG_WRITE_INTERLACING_SUPPORTED)
728 /* intialize interlace handling. If image is not interlaced,
729 this will set pass to 1 */
730 num_pass = png_set_interlace_handling(png_ptr);
731#else
732 num_pass = 1;
733#endif
734 /* loop through passes */
735 for (pass = 0; pass < num_pass; pass++)
736 {
737 /* loop through image */
738 for (i = 0, rp = image; i < png_ptr->height; i++, rp++)
739 {
740 png_write_row(png_ptr, *rp);
741 }
742 }
743}
744
745/* called by user to write a row of image data */
746void PNGAPI
747png_write_row(png_structp png_ptr, png_bytep row)
748{
749 if (png_ptr == NULL)
750 return;
751 png_debug2(1, "in png_write_row (row %ld, pass %d)\n",
752 png_ptr->row_number, png_ptr->pass);
753
754 /* initialize transformations and other stuff if first time */
755 if (png_ptr->row_number == 0 && png_ptr->pass == 0)
756 {
757 /* make sure we wrote the header info */
758 if (!(png_ptr->mode & PNG_WROTE_INFO_BEFORE_PLTE))
759 png_error(png_ptr,
760 "png_write_info was never called before png_write_row.");
761
762 /* check for transforms that have been set but were defined out */
763#if !defined(PNG_WRITE_INVERT_SUPPORTED) && defined(PNG_READ_INVERT_SUPPORTED)
764 if (png_ptr->transformations & PNG_INVERT_MONO)
765 png_warning(png_ptr, "PNG_WRITE_INVERT_SUPPORTED is not defined.");
766#endif
767#if !defined(PNG_WRITE_FILLER_SUPPORTED) && defined(PNG_READ_FILLER_SUPPORTED)
768 if (png_ptr->transformations & PNG_FILLER)
769 png_warning(png_ptr, "PNG_WRITE_FILLER_SUPPORTED is not defined.");
770#endif
771#if !defined(PNG_WRITE_PACKSWAP_SUPPORTED) && defined(PNG_READ_PACKSWAP_SUPPORTED)
772 if (png_ptr->transformations & PNG_PACKSWAP)
773 png_warning(png_ptr, "PNG_WRITE_PACKSWAP_SUPPORTED is not defined.");
774#endif
775#if !defined(PNG_WRITE_PACK_SUPPORTED) && defined(PNG_READ_PACK_SUPPORTED)
776 if (png_ptr->transformations & PNG_PACK)
777 png_warning(png_ptr, "PNG_WRITE_PACK_SUPPORTED is not defined.");
778#endif
779#if !defined(PNG_WRITE_SHIFT_SUPPORTED) && defined(PNG_READ_SHIFT_SUPPORTED)
780 if (png_ptr->transformations & PNG_SHIFT)
781 png_warning(png_ptr, "PNG_WRITE_SHIFT_SUPPORTED is not defined.");
782#endif
783#if !defined(PNG_WRITE_BGR_SUPPORTED) && defined(PNG_READ_BGR_SUPPORTED)
784 if (png_ptr->transformations & PNG_BGR)
785 png_warning(png_ptr, "PNG_WRITE_BGR_SUPPORTED is not defined.");
786#endif
787#if !defined(PNG_WRITE_SWAP_SUPPORTED) && defined(PNG_READ_SWAP_SUPPORTED)
788 if (png_ptr->transformations & PNG_SWAP_BYTES)
789 png_warning(png_ptr, "PNG_WRITE_SWAP_SUPPORTED is not defined.");
790#endif
791
792 png_write_start_row(png_ptr);
793 }
794
795#if defined(PNG_WRITE_INTERLACING_SUPPORTED)
796 /* if interlaced and not interested in row, return */
797 if (png_ptr->interlaced && (png_ptr->transformations & PNG_INTERLACE))
798 {
799 switch (png_ptr->pass)
800 {
801 case 0:
802 if (png_ptr->row_number & 0x07)
803 {
804 png_write_finish_row(png_ptr);
805 return;
806 }
807 break;
808 case 1:
809 if ((png_ptr->row_number & 0x07) || png_ptr->width < 5)
810 {
811 png_write_finish_row(png_ptr);
812 return;
813 }
814 break;
815 case 2:
816 if ((png_ptr->row_number & 0x07) != 4)
817 {
818 png_write_finish_row(png_ptr);
819 return;
820 }
821 break;
822 case 3:
823 if ((png_ptr->row_number & 0x03) || png_ptr->width < 3)
824 {
825 png_write_finish_row(png_ptr);
826 return;
827 }
828 break;
829 case 4:
830 if ((png_ptr->row_number & 0x03) != 2)
831 {
832 png_write_finish_row(png_ptr);
833 return;
834 }
835 break;
836 case 5:
837 if ((png_ptr->row_number & 0x01) || png_ptr->width < 2)
838 {
839 png_write_finish_row(png_ptr);
840 return;
841 }
842 break;
843 case 6:
844 if (!(png_ptr->row_number & 0x01))
845 {
846 png_write_finish_row(png_ptr);
847 return;
848 }
849 break;
850 }
851 }
852#endif
853
854 /* set up row info for transformations */
855 png_ptr->row_info.color_type = png_ptr->color_type;
856 png_ptr->row_info.width = png_ptr->usr_width;
857 png_ptr->row_info.channels = png_ptr->usr_channels;
858 png_ptr->row_info.bit_depth = png_ptr->usr_bit_depth;
859 png_ptr->row_info.pixel_depth = (png_byte)(png_ptr->row_info.bit_depth *
860 png_ptr->row_info.channels);
861
862 png_ptr->row_info.rowbytes = PNG_ROWBYTES(png_ptr->row_info.pixel_depth,
863 png_ptr->row_info.width);
864
865 png_debug1(3, "row_info->color_type = %d\n", png_ptr->row_info.color_type);
866 png_debug1(3, "row_info->width = %lu\n", png_ptr->row_info.width);
867 png_debug1(3, "row_info->channels = %d\n", png_ptr->row_info.channels);
868 png_debug1(3, "row_info->bit_depth = %d\n", png_ptr->row_info.bit_depth);
869 png_debug1(3, "row_info->pixel_depth = %d\n", png_ptr->row_info.pixel_depth);
870 png_debug1(3, "row_info->rowbytes = %lu\n", png_ptr->row_info.rowbytes);
871
872 /* Copy user's row into buffer, leaving room for filter byte. */
873 png_memcpy_check(png_ptr, png_ptr->row_buf + 1, row,
874 png_ptr->row_info.rowbytes);
875
876#if defined(PNG_WRITE_INTERLACING_SUPPORTED)
877 /* handle interlacing */
878 if (png_ptr->interlaced && png_ptr->pass < 6 &&
879 (png_ptr->transformations & PNG_INTERLACE))
880 {
881 png_do_write_interlace(&(png_ptr->row_info),
882 png_ptr->row_buf + 1, png_ptr->pass);
883 /* this should always get caught above, but still ... */
884 if (!(png_ptr->row_info.width))
885 {
886 png_write_finish_row(png_ptr);
887 return;
888 }
889 }
890#endif
891
892 /* handle other transformations */
893 if (png_ptr->transformations)
894 png_do_write_transformations(png_ptr);
895
896#if defined(PNG_MNG_FEATURES_SUPPORTED)
897 /* Write filter_method 64 (intrapixel differencing) only if
898 * 1. Libpng was compiled with PNG_MNG_FEATURES_SUPPORTED and
899 * 2. Libpng did not write a PNG signature (this filter_method is only
900 * used in PNG datastreams that are embedded in MNG datastreams) and
901 * 3. The application called png_permit_mng_features with a mask that
902 * included PNG_FLAG_MNG_FILTER_64 and
903 * 4. The filter_method is 64 and
904 * 5. The color_type is RGB or RGBA
905 */
906 if((png_ptr->mng_features_permitted & PNG_FLAG_MNG_FILTER_64) &&
907 (png_ptr->filter_type == PNG_INTRAPIXEL_DIFFERENCING))
908 {
909 /* Intrapixel differencing */
910 png_do_write_intrapixel(&(png_ptr->row_info), png_ptr->row_buf + 1);
911 }
912#endif
913
914 /* Find a filter if necessary, filter the row and write it out. */
915 png_write_find_filter(png_ptr, &(png_ptr->row_info));
916
917 if (png_ptr->write_row_fn != NULL)
918 (*(png_ptr->write_row_fn))(png_ptr, png_ptr->row_number, png_ptr->pass);
919}
920
921#if defined(PNG_WRITE_FLUSH_SUPPORTED)
922/* Set the automatic flush interval or 0 to turn flushing off */
923void PNGAPI
924png_set_flush(png_structp png_ptr, int nrows)
925{
926 png_debug(1, "in png_set_flush\n");
927 if (png_ptr == NULL)
928 return;
929 png_ptr->flush_dist = (nrows < 0 ? 0 : nrows);
930}
931
932/* flush the current output buffers now */
933void PNGAPI
934png_write_flush(png_structp png_ptr)
935{
936 int wrote_IDAT;
937
938 png_debug(1, "in png_write_flush\n");
939 if (png_ptr == NULL)
940 return;
941 /* We have already written out all of the data */
942 if (png_ptr->row_number >= png_ptr->num_rows)
943 return;
944
945 do
946 {
947 int ret;
948
949 /* compress the data */
950 ret = deflate(&png_ptr->zstream, Z_SYNC_FLUSH);
951 wrote_IDAT = 0;
952
953 /* check for compression errors */
954 if (ret != Z_OK)
955 {
956 if (png_ptr->zstream.msg != NULL)
957 png_error(png_ptr, png_ptr->zstream.msg);
958 else
959 png_error(png_ptr, "zlib error");
960 }
961
962 if (!(png_ptr->zstream.avail_out))
963 {
964 /* write the IDAT and reset the zlib output buffer */
965 png_write_IDAT(png_ptr, png_ptr->zbuf,
966 png_ptr->zbuf_size);
967 png_ptr->zstream.next_out = png_ptr->zbuf;
968 png_ptr->zstream.avail_out = (uInt)png_ptr->zbuf_size;
969 wrote_IDAT = 1;
970 }
971 } while(wrote_IDAT == 1);
972
973 /* If there is any data left to be output, write it into a new IDAT */
974 if (png_ptr->zbuf_size != png_ptr->zstream.avail_out)
975 {
976 /* write the IDAT and reset the zlib output buffer */
977 png_write_IDAT(png_ptr, png_ptr->zbuf,
978 png_ptr->zbuf_size - png_ptr->zstream.avail_out);
979 png_ptr->zstream.next_out = png_ptr->zbuf;
980 png_ptr->zstream.avail_out = (uInt)png_ptr->zbuf_size;
981 }
982 png_ptr->flush_rows = 0;
983 png_flush(png_ptr);
984}
985#endif /* PNG_WRITE_FLUSH_SUPPORTED */
986
987/* free all memory used by the write */
988void PNGAPI
989png_destroy_write_struct(png_structpp png_ptr_ptr, png_infopp info_ptr_ptr)
990{
991 png_structp png_ptr = NULL;
992 png_infop info_ptr = NULL;
993#ifdef PNG_USER_MEM_SUPPORTED
994 png_free_ptr free_fn = NULL;
995 png_voidp mem_ptr = NULL;
996#endif
997
998 png_debug(1, "in png_destroy_write_struct\n");
999 if (png_ptr_ptr != NULL)
1000 {
1001 png_ptr = *png_ptr_ptr;
1002#ifdef PNG_USER_MEM_SUPPORTED
1003 free_fn = png_ptr->free_fn;
1004 mem_ptr = png_ptr->mem_ptr;
1005#endif
1006 }
1007
1008#ifdef PNG_USER_MEM_SUPPORTED
1009 if (png_ptr != NULL)
1010 {
1011 free_fn = png_ptr->free_fn;
1012 mem_ptr = png_ptr->mem_ptr;
1013 }
1014#endif
1015
1016 if (info_ptr_ptr != NULL)
1017 info_ptr = *info_ptr_ptr;
1018
1019 if (info_ptr != NULL)
1020 {
1021 if (png_ptr != NULL)
1022 {
1023 png_free_data(png_ptr, info_ptr, PNG_FREE_ALL, -1);
1024
1025#if defined(PNG_UNKNOWN_CHUNKS_SUPPORTED)
1026 if (png_ptr->num_chunk_list)
1027 {
1028 png_free(png_ptr, png_ptr->chunk_list);
1029 png_ptr->chunk_list=NULL;
1030 png_ptr->num_chunk_list=0;
1031 }
1032#endif
1033 }
1034
1035#ifdef PNG_USER_MEM_SUPPORTED
1036 png_destroy_struct_2((png_voidp)info_ptr, (png_free_ptr)free_fn,
1037 (png_voidp)mem_ptr);
1038#else
1039 png_destroy_struct((png_voidp)info_ptr);
1040#endif
1041 *info_ptr_ptr = NULL;
1042 }
1043
1044 if (png_ptr != NULL)
1045 {
1046 png_write_destroy(png_ptr);
1047#ifdef PNG_USER_MEM_SUPPORTED
1048 png_destroy_struct_2((png_voidp)png_ptr, (png_free_ptr)free_fn,
1049 (png_voidp)mem_ptr);
1050#else
1051 png_destroy_struct((png_voidp)png_ptr);
1052#endif
1053 *png_ptr_ptr = NULL;
1054 }
1055}
1056
1057
1058/* Free any memory used in png_ptr struct (old method) */
1059void /* PRIVATE */
1060png_write_destroy(png_structp png_ptr)
1061{
1062#ifdef PNG_SETJMP_SUPPORTED
1063 jmp_buf tmp_jmp; /* save jump buffer */
1064#endif
1065 png_error_ptr error_fn;
1066 png_error_ptr warning_fn;
1067 png_voidp error_ptr;
1068#ifdef PNG_USER_MEM_SUPPORTED
1069 png_free_ptr free_fn;
1070#endif
1071
1072 png_debug(1, "in png_write_destroy\n");
1073 /* free any memory zlib uses */
1074 deflateEnd(&png_ptr->zstream);
1075
1076 /* free our memory. png_free checks NULL for us. */
1077 png_free(png_ptr, png_ptr->zbuf);
1078 png_free(png_ptr, png_ptr->row_buf);
1079#ifndef PNG_NO_WRITE_FILTERING
1080 png_free(png_ptr, png_ptr->prev_row);
1081 png_free(png_ptr, png_ptr->sub_row);
1082 png_free(png_ptr, png_ptr->up_row);
1083 png_free(png_ptr, png_ptr->avg_row);
1084 png_free(png_ptr, png_ptr->paeth_row);
1085#endif
1086
1087#if defined(PNG_TIME_RFC1123_SUPPORTED)
1088 png_free(png_ptr, png_ptr->time_buffer);
1089#endif
1090
1091#if defined(PNG_WRITE_WEIGHTED_FILTER_SUPPORTED)
1092 png_free(png_ptr, png_ptr->prev_filters);
1093 png_free(png_ptr, png_ptr->filter_weights);
1094 png_free(png_ptr, png_ptr->inv_filter_weights);
1095 png_free(png_ptr, png_ptr->filter_costs);
1096 png_free(png_ptr, png_ptr->inv_filter_costs);
1097#endif
1098
1099#ifdef PNG_SETJMP_SUPPORTED
1100 /* reset structure */
1101 png_memcpy(tmp_jmp, png_ptr->jmpbuf, png_sizeof (jmp_buf));
1102#endif
1103
1104 error_fn = png_ptr->error_fn;
1105 warning_fn = png_ptr->warning_fn;
1106 error_ptr = png_ptr->error_ptr;
1107#ifdef PNG_USER_MEM_SUPPORTED
1108 free_fn = png_ptr->free_fn;
1109#endif
1110
1111 png_memset(png_ptr, 0, png_sizeof (png_struct));
1112
1113 png_ptr->error_fn = error_fn;
1114 png_ptr->warning_fn = warning_fn;
1115 png_ptr->error_ptr = error_ptr;
1116#ifdef PNG_USER_MEM_SUPPORTED
1117 png_ptr->free_fn = free_fn;
1118#endif
1119
1120#ifdef PNG_SETJMP_SUPPORTED
1121 png_memcpy(png_ptr->jmpbuf, tmp_jmp, png_sizeof (jmp_buf));
1122#endif
1123}
1124
1125/* Allow the application to select one or more row filters to use. */
1126void PNGAPI
1127png_set_filter(png_structp png_ptr, int method, int filters)
1128{
1129 png_debug(1, "in png_set_filter\n");
1130 if (png_ptr == NULL)
1131 return;
1132#if defined(PNG_MNG_FEATURES_SUPPORTED)
1133 if((png_ptr->mng_features_permitted & PNG_FLAG_MNG_FILTER_64) &&
1134 (method == PNG_INTRAPIXEL_DIFFERENCING))
1135 method = PNG_FILTER_TYPE_BASE;
1136#endif
1137 if (method == PNG_FILTER_TYPE_BASE)
1138 {
1139 switch (filters & (PNG_ALL_FILTERS | 0x07))
1140 {
1141#ifndef PNG_NO_WRITE_FILTER
1142 case 5:
1143 case 6:
1144 case 7: png_warning(png_ptr, "Unknown row filter for method 0");
1145#endif /* PNG_NO_WRITE_FILTER */
1146 case PNG_FILTER_VALUE_NONE:
1147 png_ptr->do_filter=PNG_FILTER_NONE; break;
1148#ifndef PNG_NO_WRITE_FILTER
1149 case PNG_FILTER_VALUE_SUB:
1150 png_ptr->do_filter=PNG_FILTER_SUB; break;
1151 case PNG_FILTER_VALUE_UP:
1152 png_ptr->do_filter=PNG_FILTER_UP; break;
1153 case PNG_FILTER_VALUE_AVG:
1154 png_ptr->do_filter=PNG_FILTER_AVG; break;
1155 case PNG_FILTER_VALUE_PAETH:
1156 png_ptr->do_filter=PNG_FILTER_PAETH; break;
1157 default: png_ptr->do_filter = (png_byte)filters; break;
1158#else
1159 default: png_warning(png_ptr, "Unknown row filter for method 0");
1160#endif /* PNG_NO_WRITE_FILTER */
1161 }
1162
1163 /* If we have allocated the row_buf, this means we have already started
1164 * with the image and we should have allocated all of the filter buffers
1165 * that have been selected. If prev_row isn't already allocated, then
1166 * it is too late to start using the filters that need it, since we
1167 * will be missing the data in the previous row. If an application
1168 * wants to start and stop using particular filters during compression,
1169 * it should start out with all of the filters, and then add and
1170 * remove them after the start of compression.
1171 */
1172 if (png_ptr->row_buf != NULL)
1173 {
1174#ifndef PNG_NO_WRITE_FILTER
1175 if ((png_ptr->do_filter & PNG_FILTER_SUB) && png_ptr->sub_row == NULL)
1176 {
1177 png_ptr->sub_row = (png_bytep)png_malloc(png_ptr,
1178 (png_ptr->rowbytes + 1));
1179 png_ptr->sub_row[0] = PNG_FILTER_VALUE_SUB;
1180 }
1181
1182 if ((png_ptr->do_filter & PNG_FILTER_UP) && png_ptr->up_row == NULL)
1183 {
1184 if (png_ptr->prev_row == NULL)
1185 {
1186 png_warning(png_ptr, "Can't add Up filter after starting");
1187 png_ptr->do_filter &= ~PNG_FILTER_UP;
1188 }
1189 else
1190 {
1191 png_ptr->up_row = (png_bytep)png_malloc(png_ptr,
1192 (png_ptr->rowbytes + 1));
1193 png_ptr->up_row[0] = PNG_FILTER_VALUE_UP;
1194 }
1195 }
1196
1197 if ((png_ptr->do_filter & PNG_FILTER_AVG) && png_ptr->avg_row == NULL)
1198 {
1199 if (png_ptr->prev_row == NULL)
1200 {
1201 png_warning(png_ptr, "Can't add Average filter after starting");
1202 png_ptr->do_filter &= ~PNG_FILTER_AVG;
1203 }
1204 else
1205 {
1206 png_ptr->avg_row = (png_bytep)png_malloc(png_ptr,
1207 (png_ptr->rowbytes + 1));
1208 png_ptr->avg_row[0] = PNG_FILTER_VALUE_AVG;
1209 }
1210 }
1211
1212 if ((png_ptr->do_filter & PNG_FILTER_PAETH) &&
1213 png_ptr->paeth_row == NULL)
1214 {
1215 if (png_ptr->prev_row == NULL)
1216 {
1217 png_warning(png_ptr, "Can't add Paeth filter after starting");
1218 png_ptr->do_filter &= (png_byte)(~PNG_FILTER_PAETH);
1219 }
1220 else
1221 {
1222 png_ptr->paeth_row = (png_bytep)png_malloc(png_ptr,
1223 (png_ptr->rowbytes + 1));
1224 png_ptr->paeth_row[0] = PNG_FILTER_VALUE_PAETH;
1225 }
1226 }
1227
1228 if (png_ptr->do_filter == PNG_NO_FILTERS)
1229#endif /* PNG_NO_WRITE_FILTER */
1230 png_ptr->do_filter = PNG_FILTER_NONE;
1231 }
1232 }
1233 else
1234 png_error(png_ptr, "Unknown custom filter method");
1235}
1236
1237/* This allows us to influence the way in which libpng chooses the "best"
1238 * filter for the current scanline. While the "minimum-sum-of-absolute-
1239 * differences metric is relatively fast and effective, there is some
1240 * question as to whether it can be improved upon by trying to keep the
1241 * filtered data going to zlib more consistent, hopefully resulting in
1242 * better compression.
1243 */
1244#if defined(PNG_WRITE_WEIGHTED_FILTER_SUPPORTED) /* GRR 970116 */
1245void PNGAPI
1246png_set_filter_heuristics(png_structp png_ptr, int heuristic_method,
1247 int num_weights, png_doublep filter_weights,
1248 png_doublep filter_costs)
1249{
1250 int i;
1251
1252 png_debug(1, "in png_set_filter_heuristics\n");
1253 if (png_ptr == NULL)
1254 return;
1255 if (heuristic_method >= PNG_FILTER_HEURISTIC_LAST)
1256 {
1257 png_warning(png_ptr, "Unknown filter heuristic method");
1258 return;
1259 }
1260
1261 if (heuristic_method == PNG_FILTER_HEURISTIC_DEFAULT)
1262 {
1263 heuristic_method = PNG_FILTER_HEURISTIC_UNWEIGHTED;
1264 }
1265
1266 if (num_weights < 0 || filter_weights == NULL ||
1267 heuristic_method == PNG_FILTER_HEURISTIC_UNWEIGHTED)
1268 {
1269 num_weights = 0;
1270 }
1271
1272 png_ptr->num_prev_filters = (png_byte)num_weights;
1273 png_ptr->heuristic_method = (png_byte)heuristic_method;
1274
1275 if (num_weights > 0)
1276 {
1277 if (png_ptr->prev_filters == NULL)
1278 {
1279 png_ptr->prev_filters = (png_bytep)png_malloc(png_ptr,
1280 (png_uint_32)(png_sizeof(png_byte) * num_weights));
1281
1282 /* To make sure that the weighting starts out fairly */
1283 for (i = 0; i < num_weights; i++)
1284 {
1285 png_ptr->prev_filters[i] = 255;
1286 }
1287 }
1288
1289 if (png_ptr->filter_weights == NULL)
1290 {
1291 png_ptr->filter_weights = (png_uint_16p)png_malloc(png_ptr,
1292 (png_uint_32)(png_sizeof(png_uint_16) * num_weights));
1293
1294 png_ptr->inv_filter_weights = (png_uint_16p)png_malloc(png_ptr,
1295 (png_uint_32)(png_sizeof(png_uint_16) * num_weights));
1296 for (i = 0; i < num_weights; i++)
1297 {
1298 png_ptr->inv_filter_weights[i] =
1299 png_ptr->filter_weights[i] = PNG_WEIGHT_FACTOR;
1300 }
1301 }
1302
1303 for (i = 0; i < num_weights; i++)
1304 {
1305 if (filter_weights[i] < 0.0)
1306 {
1307 png_ptr->inv_filter_weights[i] =
1308 png_ptr->filter_weights[i] = PNG_WEIGHT_FACTOR;
1309 }
1310 else
1311 {
1312 png_ptr->inv_filter_weights[i] =
1313 (png_uint_16)((double)PNG_WEIGHT_FACTOR*filter_weights[i]+0.5);
1314 png_ptr->filter_weights[i] =
1315 (png_uint_16)((double)PNG_WEIGHT_FACTOR/filter_weights[i]+0.5);
1316 }
1317 }
1318 }
1319
1320 /* If, in the future, there are other filter methods, this would
1321 * need to be based on png_ptr->filter.
1322 */
1323 if (png_ptr->filter_costs == NULL)
1324 {
1325 png_ptr->filter_costs = (png_uint_16p)png_malloc(png_ptr,
1326 (png_uint_32)(png_sizeof(png_uint_16) * PNG_FILTER_VALUE_LAST));
1327
1328 png_ptr->inv_filter_costs = (png_uint_16p)png_malloc(png_ptr,
1329 (png_uint_32)(png_sizeof(png_uint_16) * PNG_FILTER_VALUE_LAST));
1330
1331 for (i = 0; i < PNG_FILTER_VALUE_LAST; i++)
1332 {
1333 png_ptr->inv_filter_costs[i] =
1334 png_ptr->filter_costs[i] = PNG_COST_FACTOR;
1335 }
1336 }
1337
1338 /* Here is where we set the relative costs of the different filters. We
1339 * should take the desired compression level into account when setting
1340 * the costs, so that Paeth, for instance, has a high relative cost at low
1341 * compression levels, while it has a lower relative cost at higher
1342 * compression settings. The filter types are in order of increasing
1343 * relative cost, so it would be possible to do this with an algorithm.
1344 */
1345 for (i = 0; i < PNG_FILTER_VALUE_LAST; i++)
1346 {
1347 if (filter_costs == NULL || filter_costs[i] < 0.0)
1348 {
1349 png_ptr->inv_filter_costs[i] =
1350 png_ptr->filter_costs[i] = PNG_COST_FACTOR;
1351 }
1352 else if (filter_costs[i] >= 1.0)
1353 {
1354 png_ptr->inv_filter_costs[i] =
1355 (png_uint_16)((double)PNG_COST_FACTOR / filter_costs[i] + 0.5);
1356 png_ptr->filter_costs[i] =
1357 (png_uint_16)((double)PNG_COST_FACTOR * filter_costs[i] + 0.5);
1358 }
1359 }
1360}
1361#endif /* PNG_WRITE_WEIGHTED_FILTER_SUPPORTED */
1362
1363void PNGAPI
1364png_set_compression_level(png_structp png_ptr, int level)
1365{
1366 png_debug(1, "in png_set_compression_level\n");
1367 if (png_ptr == NULL)
1368 return;
1369 png_ptr->flags |= PNG_FLAG_ZLIB_CUSTOM_LEVEL;
1370 png_ptr->zlib_level = level;
1371}
1372
1373void PNGAPI
1374png_set_compression_mem_level(png_structp png_ptr, int mem_level)
1375{
1376 png_debug(1, "in png_set_compression_mem_level\n");
1377 if (png_ptr == NULL)
1378 return;
1379 png_ptr->flags |= PNG_FLAG_ZLIB_CUSTOM_MEM_LEVEL;
1380 png_ptr->zlib_mem_level = mem_level;
1381}
1382
1383void PNGAPI
1384png_set_compression_strategy(png_structp png_ptr, int strategy)
1385{
1386 png_debug(1, "in png_set_compression_strategy\n");
1387 if (png_ptr == NULL)
1388 return;
1389 png_ptr->flags |= PNG_FLAG_ZLIB_CUSTOM_STRATEGY;
1390 png_ptr->zlib_strategy = strategy;
1391}
1392
1393void PNGAPI
1394png_set_compression_window_bits(png_structp png_ptr, int window_bits)
1395{
1396 if (png_ptr == NULL)
1397 return;
1398 if (window_bits > 15)
1399 png_warning(png_ptr, "Only compression windows <= 32k supported by PNG");
1400 else if (window_bits < 8)
1401 png_warning(png_ptr, "Only compression windows >= 256 supported by PNG");
1402#ifndef WBITS_8_OK
1403 /* avoid libpng bug with 256-byte windows */
1404 if (window_bits == 8)
1405 {
1406 png_warning(png_ptr, "Compression window is being reset to 512");
1407 window_bits=9;
1408 }
1409#endif
1410 png_ptr->flags |= PNG_FLAG_ZLIB_CUSTOM_WINDOW_BITS;
1411 png_ptr->zlib_window_bits = window_bits;
1412}
1413
1414void PNGAPI
1415png_set_compression_method(png_structp png_ptr, int method)
1416{
1417 png_debug(1, "in png_set_compression_method\n");
1418 if (png_ptr == NULL)
1419 return;
1420 if (method != 8)
1421 png_warning(png_ptr, "Only compression method 8 is supported by PNG");
1422 png_ptr->flags |= PNG_FLAG_ZLIB_CUSTOM_METHOD;
1423 png_ptr->zlib_method = method;
1424}
1425
1426void PNGAPI
1427png_set_write_status_fn(png_structp png_ptr, png_write_status_ptr write_row_fn)
1428{
1429 if (png_ptr == NULL)
1430 return;
1431 png_ptr->write_row_fn = write_row_fn;
1432}
1433
1434#if defined(PNG_WRITE_USER_TRANSFORM_SUPPORTED)
1435void PNGAPI
1436png_set_write_user_transform_fn(png_structp png_ptr, png_user_transform_ptr
1437 write_user_transform_fn)
1438{
1439 png_debug(1, "in png_set_write_user_transform_fn\n");
1440 if (png_ptr == NULL)
1441 return;
1442 png_ptr->transformations |= PNG_USER_TRANSFORM;
1443 png_ptr->write_user_transform_fn = write_user_transform_fn;
1444}
1445#endif
1446
1447
1448#if defined(PNG_INFO_IMAGE_SUPPORTED)
1449void PNGAPI
1450png_write_png(png_structp png_ptr, png_infop info_ptr,
1451 int transforms, voidp params)
1452{
1453 if (png_ptr == NULL || info_ptr == NULL)
1454 return;
1455#if defined(PNG_WRITE_INVERT_ALPHA_SUPPORTED)
1456 /* invert the alpha channel from opacity to transparency */
1457 if (transforms & PNG_TRANSFORM_INVERT_ALPHA)
1458 png_set_invert_alpha(png_ptr);
1459#endif
1460
1461 /* Write the file header information. */
1462 png_write_info(png_ptr, info_ptr);
1463
1464 /* ------ these transformations don't touch the info structure ------- */
1465
1466#if defined(PNG_WRITE_INVERT_SUPPORTED)
1467 /* invert monochrome pixels */
1468 if (transforms & PNG_TRANSFORM_INVERT_MONO)
1469 png_set_invert_mono(png_ptr);
1470#endif
1471
1472#if defined(PNG_WRITE_SHIFT_SUPPORTED)
1473 /* Shift the pixels up to a legal bit depth and fill in
1474 * as appropriate to correctly scale the image.
1475 */
1476 if ((transforms & PNG_TRANSFORM_SHIFT)
1477 && (info_ptr->valid & PNG_INFO_sBIT))
1478 png_set_shift(png_ptr, &info_ptr->sig_bit);
1479#endif
1480
1481#if defined(PNG_WRITE_PACK_SUPPORTED)
1482 /* pack pixels into bytes */
1483 if (transforms & PNG_TRANSFORM_PACKING)
1484 png_set_packing(png_ptr);
1485#endif
1486
1487#if defined(PNG_WRITE_SWAP_ALPHA_SUPPORTED)
1488 /* swap location of alpha bytes from ARGB to RGBA */
1489 if (transforms & PNG_TRANSFORM_SWAP_ALPHA)
1490 png_set_swap_alpha(png_ptr);
1491#endif
1492
1493#if defined(PNG_WRITE_FILLER_SUPPORTED)
1494 /* Get rid of filler (OR ALPHA) bytes, pack XRGB/RGBX/ARGB/RGBA into
1495 * RGB (4 channels -> 3 channels). The second parameter is not used.
1496 */
1497 if (transforms & PNG_TRANSFORM_STRIP_FILLER)
1498 png_set_filler(png_ptr, 0, PNG_FILLER_BEFORE);
1499#endif
1500
1501#if defined(PNG_WRITE_BGR_SUPPORTED)
1502 /* flip BGR pixels to RGB */
1503 if (transforms & PNG_TRANSFORM_BGR)
1504 png_set_bgr(png_ptr);
1505#endif
1506
1507#if defined(PNG_WRITE_SWAP_SUPPORTED)
1508 /* swap bytes of 16-bit files to most significant byte first */
1509 if (transforms & PNG_TRANSFORM_SWAP_ENDIAN)
1510 png_set_swap(png_ptr);
1511#endif
1512
1513#if defined(PNG_WRITE_PACKSWAP_SUPPORTED)
1514 /* swap bits of 1, 2, 4 bit packed pixel formats */
1515 if (transforms & PNG_TRANSFORM_PACKSWAP)
1516 png_set_packswap(png_ptr);
1517#endif
1518
1519 /* ----------------------- end of transformations ------------------- */
1520
1521 /* write the bits */
1522 if (info_ptr->valid & PNG_INFO_IDAT)
1523 png_write_image(png_ptr, info_ptr->row_pointers);
1524
1525 /* It is REQUIRED to call this to finish writing the rest of the file */
1526 png_write_end(png_ptr, info_ptr);
1527
1528 transforms = transforms; /* quiet compiler warnings */
1529 params = params;
1530}
1531#endif
1532#endif /* PNG_WRITE_SUPPORTED */
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