2
/* pngwrite.c - general routines to write a PNG file
4
* libpng 1.2.8 - December 3, 2004
5
* For conditions of distribution and use, see copyright notice in png.h
6
* Copyright (c) 1998-2004 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.)
11
/* get internal access to png.h */
14
#ifdef PNG_WRITE_SUPPORTED
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.
26
png_write_info_before_PLTE(png_structp png_ptr, png_infop info_ptr)
28
png_debug(1, "in png_write_info_before_PLTE\n");
29
if (!(png_ptr->mode & PNG_WROTE_INFO_BEFORE_PLTE))
31
png_write_sig(png_ptr); /* write PNG signature */
32
#if defined(PNG_MNG_FEATURES_SUPPORTED)
33
if((png_ptr->mode&PNG_HAVE_PNG_SIGNATURE)&&(png_ptr->mng_features_permitted))
35
png_warning(png_ptr,"MNG features are not allowed in a PNG datastream\n");
36
png_ptr->mng_features_permitted=0;
39
/* write IHDR information. */
40
png_write_IHDR(png_ptr, info_ptr->width, info_ptr->height,
41
info_ptr->bit_depth, info_ptr->color_type, info_ptr->compression_type,
42
info_ptr->filter_type,
43
#if defined(PNG_WRITE_INTERLACING_SUPPORTED)
44
info_ptr->interlace_type);
48
/* the rest of these check to see if the valid field has the appropriate
49
flag set, and if it does, writes the chunk. */
50
#if defined(PNG_WRITE_gAMA_SUPPORTED)
51
if (info_ptr->valid & PNG_INFO_gAMA)
53
# ifdef PNG_FLOATING_POINT_SUPPORTED
54
png_write_gAMA(png_ptr, info_ptr->gamma);
56
#ifdef PNG_FIXED_POINT_SUPPORTED
57
png_write_gAMA_fixed(png_ptr, info_ptr->int_gamma);
62
#if defined(PNG_WRITE_sRGB_SUPPORTED)
63
if (info_ptr->valid & PNG_INFO_sRGB)
64
png_write_sRGB(png_ptr, (int)info_ptr->srgb_intent);
66
#if defined(PNG_WRITE_iCCP_SUPPORTED)
67
if (info_ptr->valid & PNG_INFO_iCCP)
68
png_write_iCCP(png_ptr, info_ptr->iccp_name, PNG_COMPRESSION_TYPE_BASE,
69
info_ptr->iccp_profile, (int)info_ptr->iccp_proflen);
71
#if defined(PNG_WRITE_sBIT_SUPPORTED)
72
if (info_ptr->valid & PNG_INFO_sBIT)
73
png_write_sBIT(png_ptr, &(info_ptr->sig_bit), info_ptr->color_type);
75
#if defined(PNG_WRITE_cHRM_SUPPORTED)
76
if (info_ptr->valid & PNG_INFO_cHRM)
78
#ifdef PNG_FLOATING_POINT_SUPPORTED
79
png_write_cHRM(png_ptr,
80
info_ptr->x_white, info_ptr->y_white,
81
info_ptr->x_red, info_ptr->y_red,
82
info_ptr->x_green, info_ptr->y_green,
83
info_ptr->x_blue, info_ptr->y_blue);
85
# ifdef PNG_FIXED_POINT_SUPPORTED
86
png_write_cHRM_fixed(png_ptr,
87
info_ptr->int_x_white, info_ptr->int_y_white,
88
info_ptr->int_x_red, info_ptr->int_y_red,
89
info_ptr->int_x_green, info_ptr->int_y_green,
90
info_ptr->int_x_blue, info_ptr->int_y_blue);
95
#if defined(PNG_WRITE_UNKNOWN_CHUNKS_SUPPORTED)
96
if (info_ptr->unknown_chunks_num)
98
png_unknown_chunk *up;
100
png_debug(5, "writing extra chunks\n");
102
for (up = info_ptr->unknown_chunks;
103
up < info_ptr->unknown_chunks + info_ptr->unknown_chunks_num;
106
int keep=png_handle_as_unknown(png_ptr, up->name);
107
if (keep != PNG_HANDLE_CHUNK_NEVER &&
108
up->location && !(up->location & PNG_HAVE_PLTE) &&
109
!(up->location & PNG_HAVE_IDAT) &&
110
((up->name[3] & 0x20) || keep == PNG_HANDLE_CHUNK_ALWAYS ||
111
(png_ptr->flags & PNG_FLAG_KEEP_UNSAFE_CHUNKS)))
113
png_write_chunk(png_ptr, up->name, up->data, up->size);
118
png_ptr->mode |= PNG_WROTE_INFO_BEFORE_PLTE;
123
png_write_info(png_structp png_ptr, png_infop info_ptr)
125
#if defined(PNG_WRITE_TEXT_SUPPORTED) || defined(PNG_WRITE_sPLT_SUPPORTED)
129
png_debug(1, "in png_write_info\n");
131
png_write_info_before_PLTE(png_ptr, info_ptr);
133
if (info_ptr->valid & PNG_INFO_PLTE)
134
png_write_PLTE(png_ptr, info_ptr->palette,
135
(png_uint_32)info_ptr->num_palette);
136
else if (info_ptr->color_type == PNG_COLOR_TYPE_PALETTE)
137
png_error(png_ptr, "Valid palette required for paletted images\n");
139
#if defined(PNG_WRITE_tRNS_SUPPORTED)
140
if (info_ptr->valid & PNG_INFO_tRNS)
142
#if defined(PNG_WRITE_INVERT_ALPHA_SUPPORTED)
143
/* invert the alpha channel (in tRNS) */
144
if ((png_ptr->transformations & PNG_INVERT_ALPHA) &&
145
info_ptr->color_type == PNG_COLOR_TYPE_PALETTE)
148
for (j=0; j<(int)info_ptr->num_trans; j++)
149
info_ptr->trans[j] = (png_byte)(255 - info_ptr->trans[j]);
152
png_write_tRNS(png_ptr, info_ptr->trans, &(info_ptr->trans_values),
153
info_ptr->num_trans, info_ptr->color_type);
156
#if defined(PNG_WRITE_bKGD_SUPPORTED)
157
if (info_ptr->valid & PNG_INFO_bKGD)
158
png_write_bKGD(png_ptr, &(info_ptr->background), info_ptr->color_type);
160
#if defined(PNG_WRITE_hIST_SUPPORTED)
161
if (info_ptr->valid & PNG_INFO_hIST)
162
png_write_hIST(png_ptr, info_ptr->hist, info_ptr->num_palette);
164
#if defined(PNG_WRITE_oFFs_SUPPORTED)
165
if (info_ptr->valid & PNG_INFO_oFFs)
166
png_write_oFFs(png_ptr, info_ptr->x_offset, info_ptr->y_offset,
167
info_ptr->offset_unit_type);
169
#if defined(PNG_WRITE_pCAL_SUPPORTED)
170
if (info_ptr->valid & PNG_INFO_pCAL)
171
png_write_pCAL(png_ptr, info_ptr->pcal_purpose, info_ptr->pcal_X0,
172
info_ptr->pcal_X1, info_ptr->pcal_type, info_ptr->pcal_nparams,
173
info_ptr->pcal_units, info_ptr->pcal_params);
175
#if defined(PNG_WRITE_sCAL_SUPPORTED)
176
if (info_ptr->valid & PNG_INFO_sCAL)
177
#if defined(PNG_FLOATING_POINT_SUPPORTED) && !defined(PNG_NO_STDIO)
178
png_write_sCAL(png_ptr, (int)info_ptr->scal_unit,
179
info_ptr->scal_pixel_width, info_ptr->scal_pixel_height);
181
#ifdef PNG_FIXED_POINT_SUPPORTED
182
png_write_sCAL_s(png_ptr, (int)info_ptr->scal_unit,
183
info_ptr->scal_s_width, info_ptr->scal_s_height);
186
"png_write_sCAL not supported; sCAL chunk not written.\n");
190
#if defined(PNG_WRITE_pHYs_SUPPORTED)
191
if (info_ptr->valid & PNG_INFO_pHYs)
192
png_write_pHYs(png_ptr, info_ptr->x_pixels_per_unit,
193
info_ptr->y_pixels_per_unit, info_ptr->phys_unit_type);
195
#if defined(PNG_WRITE_tIME_SUPPORTED)
196
if (info_ptr->valid & PNG_INFO_tIME)
198
png_write_tIME(png_ptr, &(info_ptr->mod_time));
199
png_ptr->mode |= PNG_WROTE_tIME;
202
#if defined(PNG_WRITE_sPLT_SUPPORTED)
203
if (info_ptr->valid & PNG_INFO_sPLT)
204
for (i = 0; i < (int)info_ptr->splt_palettes_num; i++)
205
png_write_sPLT(png_ptr, info_ptr->splt_palettes + i);
207
#if defined(PNG_WRITE_TEXT_SUPPORTED)
208
/* Check to see if we need to write text chunks */
209
for (i = 0; i < info_ptr->num_text; i++)
211
png_debug2(2, "Writing header text chunk %d, type %d\n", i,
212
info_ptr->text[i].compression);
213
/* an internationalized chunk? */
214
if (info_ptr->text[i].compression > 0)
216
#if defined(PNG_WRITE_iTXt_SUPPORTED)
217
/* write international chunk */
218
png_write_iTXt(png_ptr,
219
info_ptr->text[i].compression,
220
info_ptr->text[i].key,
221
info_ptr->text[i].lang,
222
info_ptr->text[i].lang_key,
223
info_ptr->text[i].text);
225
png_warning(png_ptr, "Unable to write international text\n");
227
/* Mark this chunk as written */
228
info_ptr->text[i].compression = PNG_TEXT_COMPRESSION_NONE_WR;
230
/* If we want a compressed text chunk */
231
else if (info_ptr->text[i].compression == PNG_TEXT_COMPRESSION_zTXt)
233
#if defined(PNG_WRITE_zTXt_SUPPORTED)
234
/* write compressed chunk */
235
png_write_zTXt(png_ptr, info_ptr->text[i].key,
236
info_ptr->text[i].text, 0,
237
info_ptr->text[i].compression);
239
png_warning(png_ptr, "Unable to write compressed text\n");
241
/* Mark this chunk as written */
242
info_ptr->text[i].compression = PNG_TEXT_COMPRESSION_zTXt_WR;
244
else if (info_ptr->text[i].compression == PNG_TEXT_COMPRESSION_NONE)
246
#if defined(PNG_WRITE_tEXt_SUPPORTED)
247
/* write uncompressed chunk */
248
png_write_tEXt(png_ptr, info_ptr->text[i].key,
249
info_ptr->text[i].text,
252
png_warning(png_ptr, "Unable to write uncompressed text\n");
254
/* Mark this chunk as written */
255
info_ptr->text[i].compression = PNG_TEXT_COMPRESSION_NONE_WR;
259
#if defined(PNG_WRITE_UNKNOWN_CHUNKS_SUPPORTED)
260
if (info_ptr->unknown_chunks_num)
262
png_unknown_chunk *up;
264
png_debug(5, "writing extra chunks\n");
266
for (up = info_ptr->unknown_chunks;
267
up < info_ptr->unknown_chunks + info_ptr->unknown_chunks_num;
270
int keep=png_handle_as_unknown(png_ptr, up->name);
271
if (keep != PNG_HANDLE_CHUNK_NEVER &&
272
up->location && (up->location & PNG_HAVE_PLTE) &&
273
!(up->location & PNG_HAVE_IDAT) &&
274
((up->name[3] & 0x20) || keep == PNG_HANDLE_CHUNK_ALWAYS ||
275
(png_ptr->flags & PNG_FLAG_KEEP_UNSAFE_CHUNKS)))
277
png_write_chunk(png_ptr, up->name, up->data, up->size);
284
/* Writes the end of the PNG file. If you don't want to write comments or
285
* time information, you can pass NULL for info. If you already wrote these
286
* in png_write_info(), do not write them again here. If you have long
287
* comments, I suggest writing them here, and compressing them.
290
png_write_end(png_structp png_ptr, png_infop info_ptr)
292
png_debug(1, "in png_write_end\n");
293
if (!(png_ptr->mode & PNG_HAVE_IDAT))
294
png_error(png_ptr, "No IDATs written into file");
296
/* see if user wants us to write information chunks */
297
if (info_ptr != NULL)
299
#if defined(PNG_WRITE_TEXT_SUPPORTED)
300
int i; /* local index variable */
302
#if defined(PNG_WRITE_tIME_SUPPORTED)
303
/* check to see if user has supplied a time chunk */
304
if ((info_ptr->valid & PNG_INFO_tIME) &&
305
!(png_ptr->mode & PNG_WROTE_tIME))
306
png_write_tIME(png_ptr, &(info_ptr->mod_time));
308
#if defined(PNG_WRITE_TEXT_SUPPORTED)
309
/* loop through comment chunks */
310
for (i = 0; i < info_ptr->num_text; i++)
312
png_debug2(2, "Writing trailer text chunk %d, type %d\n", i,
313
info_ptr->text[i].compression);
314
/* an internationalized chunk? */
315
if (info_ptr->text[i].compression > 0)
317
#if defined(PNG_WRITE_iTXt_SUPPORTED)
318
/* write international chunk */
319
png_write_iTXt(png_ptr,
320
info_ptr->text[i].compression,
321
info_ptr->text[i].key,
322
info_ptr->text[i].lang,
323
info_ptr->text[i].lang_key,
324
info_ptr->text[i].text);
326
png_warning(png_ptr, "Unable to write international text\n");
328
/* Mark this chunk as written */
329
info_ptr->text[i].compression = PNG_TEXT_COMPRESSION_NONE_WR;
331
else if (info_ptr->text[i].compression >= PNG_TEXT_COMPRESSION_zTXt)
333
#if defined(PNG_WRITE_zTXt_SUPPORTED)
334
/* write compressed chunk */
335
png_write_zTXt(png_ptr, info_ptr->text[i].key,
336
info_ptr->text[i].text, 0,
337
info_ptr->text[i].compression);
339
png_warning(png_ptr, "Unable to write compressed text\n");
341
/* Mark this chunk as written */
342
info_ptr->text[i].compression = PNG_TEXT_COMPRESSION_zTXt_WR;
344
else if (info_ptr->text[i].compression == PNG_TEXT_COMPRESSION_NONE)
346
#if defined(PNG_WRITE_tEXt_SUPPORTED)
347
/* write uncompressed chunk */
348
png_write_tEXt(png_ptr, info_ptr->text[i].key,
349
info_ptr->text[i].text, 0);
351
png_warning(png_ptr, "Unable to write uncompressed text\n");
354
/* Mark this chunk as written */
355
info_ptr->text[i].compression = PNG_TEXT_COMPRESSION_NONE_WR;
359
#if defined(PNG_WRITE_UNKNOWN_CHUNKS_SUPPORTED)
360
if (info_ptr->unknown_chunks_num)
362
png_unknown_chunk *up;
364
png_debug(5, "writing extra chunks\n");
366
for (up = info_ptr->unknown_chunks;
367
up < info_ptr->unknown_chunks + info_ptr->unknown_chunks_num;
370
int keep=png_handle_as_unknown(png_ptr, up->name);
371
if (keep != PNG_HANDLE_CHUNK_NEVER &&
372
up->location && (up->location & PNG_AFTER_IDAT) &&
373
((up->name[3] & 0x20) || keep == PNG_HANDLE_CHUNK_ALWAYS ||
374
(png_ptr->flags & PNG_FLAG_KEEP_UNSAFE_CHUNKS)))
376
png_write_chunk(png_ptr, up->name, up->data, up->size);
383
png_ptr->mode |= PNG_AFTER_IDAT;
385
/* write end of PNG file */
386
png_write_IEND(png_ptr);
388
/* This flush, added in libpng-1.0.8, causes some applications to crash
389
because they do not set png_ptr->output_flush_fn */
394
#if defined(PNG_WRITE_tIME_SUPPORTED)
395
#if !defined(_WIN32_WCE)
396
/* "time.h" functions are not supported on WindowsCE */
398
png_convert_from_struct_tm(png_timep ptime, struct tm FAR * ttime)
400
png_debug(1, "in png_convert_from_struct_tm\n");
401
ptime->year = (png_uint_16)(1900 + ttime->tm_year);
402
ptime->month = (png_byte)(ttime->tm_mon + 1);
403
ptime->day = (png_byte)ttime->tm_mday;
404
ptime->hour = (png_byte)ttime->tm_hour;
405
ptime->minute = (png_byte)ttime->tm_min;
406
ptime->second = (png_byte)ttime->tm_sec;
410
png_convert_from_time_t(png_timep ptime, time_t ttime)
414
png_debug(1, "in png_convert_from_time_t\n");
415
tbuf = gmtime(&ttime);
416
png_convert_from_struct_tm(ptime, tbuf);
421
/* Initialize png_ptr structure, and allocate any memory needed */
423
png_create_write_struct(png_const_charp user_png_ver, png_voidp error_ptr,
424
png_error_ptr error_fn, png_error_ptr warn_fn)
426
#ifdef PNG_USER_MEM_SUPPORTED
427
return (png_create_write_struct_2(user_png_ver, error_ptr, error_fn,
428
warn_fn, png_voidp_NULL, png_malloc_ptr_NULL, png_free_ptr_NULL));
431
/* Alternate initialize png_ptr structure, and allocate any memory needed */
433
png_create_write_struct_2(png_const_charp user_png_ver, png_voidp error_ptr,
434
png_error_ptr error_fn, png_error_ptr warn_fn, png_voidp mem_ptr,
435
png_malloc_ptr malloc_fn, png_free_ptr free_fn)
437
#endif /* PNG_USER_MEM_SUPPORTED */
439
#ifdef PNG_SETJMP_SUPPORTED
440
#ifdef USE_FAR_KEYWORD
445
png_debug(1, "in png_create_write_struct\n");
446
#ifdef PNG_USER_MEM_SUPPORTED
447
png_ptr = (png_structp)png_create_struct_2(PNG_STRUCT_PNG,
448
(png_malloc_ptr)malloc_fn, (png_voidp)mem_ptr);
450
png_ptr = (png_structp)png_create_struct(PNG_STRUCT_PNG);
451
#endif /* PNG_USER_MEM_SUPPORTED */
455
#if !defined(PNG_1_0_X)
456
#ifdef PNG_ASSEMBLER_CODE_SUPPORTED
457
png_init_mmx_flags(png_ptr); /* 1.2.0 addition */
459
#endif /* PNG_1_0_X */
461
/* added at libpng-1.2.6 */
462
#ifdef PNG_SET_USER_LIMITS_SUPPORTED
463
png_ptr->user_width_max=PNG_USER_WIDTH_MAX;
464
png_ptr->user_height_max=PNG_USER_HEIGHT_MAX;
467
#ifdef PNG_SETJMP_SUPPORTED
468
#ifdef USE_FAR_KEYWORD
471
if (setjmp(png_ptr->jmpbuf))
474
png_free(png_ptr, png_ptr->zbuf);
476
png_destroy_struct(png_ptr);
479
#ifdef USE_FAR_KEYWORD
480
png_memcpy(png_ptr->jmpbuf,jmpbuf,png_sizeof(jmp_buf));
484
#ifdef PNG_USER_MEM_SUPPORTED
485
png_set_mem_fn(png_ptr, mem_ptr, malloc_fn, free_fn);
486
#endif /* PNG_USER_MEM_SUPPORTED */
487
png_set_error_fn(png_ptr, error_ptr, error_fn, warn_fn);
492
if(user_png_ver[i] != png_libpng_ver[i])
493
png_ptr->flags |= PNG_FLAG_LIBRARY_MISMATCH;
494
} while (png_libpng_ver[i++]);
496
if (png_ptr->flags & PNG_FLAG_LIBRARY_MISMATCH)
498
/* Libpng 0.90 and later are binary incompatible with libpng 0.89, so
499
* we must recompile any applications that use any older library version.
500
* For versions after libpng 1.0, we will be compatible, so we need
501
* only check the first digit.
503
if (user_png_ver == NULL || user_png_ver[0] != png_libpng_ver[0] ||
504
(user_png_ver[0] == '1' && user_png_ver[2] != png_libpng_ver[2]) ||
505
(user_png_ver[0] == '0' && user_png_ver[2] < '9'))
507
#if !defined(PNG_NO_STDIO) && !defined(_WIN32_WCE)
511
sprintf(msg, "Application was compiled with png.h from libpng-%.20s",
513
png_warning(png_ptr, msg);
515
sprintf(msg, "Application is running with png.c from libpng-%.20s",
517
png_warning(png_ptr, msg);
519
#ifdef PNG_ERROR_NUMBERS_SUPPORTED
523
"Incompatible libpng version in application and library");
527
/* initialize zbuf - compression buffer */
528
png_ptr->zbuf_size = PNG_ZBUF_SIZE;
529
png_ptr->zbuf = (png_bytep)png_malloc(png_ptr,
530
(png_uint_32)png_ptr->zbuf_size);
532
png_set_write_fn(png_ptr, png_voidp_NULL, png_rw_ptr_NULL,
535
#if defined(PNG_WRITE_WEIGHTED_FILTER_SUPPORTED)
536
png_set_filter_heuristics(png_ptr, PNG_FILTER_HEURISTIC_DEFAULT,
537
1, png_doublep_NULL, png_doublep_NULL);
540
#ifdef PNG_SETJMP_SUPPORTED
541
/* Applications that neglect to set up their own setjmp() and then encounter
542
a png_error() will longjmp here. Since the jmpbuf is then meaningless we
543
abort instead of returning. */
544
#ifdef USE_FAR_KEYWORD
547
png_memcpy(png_ptr->jmpbuf,jmpbuf,png_sizeof(jmp_buf));
549
if (setjmp(png_ptr->jmpbuf))
556
/* Initialize png_ptr structure, and allocate any memory needed */
557
#undef png_write_init
559
png_write_init(png_structp png_ptr)
561
/* We only come here via pre-1.0.7-compiled applications */
562
png_write_init_2(png_ptr, "1.0.6 or earlier", 0, 0);
566
png_write_init_2(png_structp png_ptr, png_const_charp user_png_ver,
567
png_size_t png_struct_size, png_size_t png_info_size)
569
/* We only come here via pre-1.0.12-compiled applications */
570
#if !defined(PNG_NO_STDIO) && !defined(_WIN32_WCE)
571
if(png_sizeof(png_struct) > png_struct_size ||
572
png_sizeof(png_info) > png_info_size)
575
png_ptr->warning_fn=NULL;
578
sprintf(msg, "Application was compiled with png.h from libpng-%.20s",
580
png_warning(png_ptr, msg);
582
sprintf(msg, "Application is running with png.c from libpng-%.20s",
584
png_warning(png_ptr, msg);
587
if(png_sizeof(png_struct) > png_struct_size)
589
png_ptr->error_fn=NULL;
590
#ifdef PNG_ERROR_NUMBERS_SUPPORTED
594
"The png struct allocated by the application for writing is too small.");
596
if(png_sizeof(png_info) > png_info_size)
598
png_ptr->error_fn=NULL;
599
#ifdef PNG_ERROR_NUMBERS_SUPPORTED
603
"The info struct allocated by the application for writing is too small.");
605
png_write_init_3(&png_ptr, user_png_ver, png_struct_size);
610
png_write_init_3(png_structpp ptr_ptr, png_const_charp user_png_ver,
611
png_size_t png_struct_size)
613
png_structp png_ptr=*ptr_ptr;
614
#ifdef PNG_SETJMP_SUPPORTED
615
jmp_buf tmp_jmp; /* to save current jump buffer */
620
if (user_png_ver[i] != png_libpng_ver[i])
622
#ifdef PNG_LEGACY_SUPPORTED
623
png_ptr->flags |= PNG_FLAG_LIBRARY_MISMATCH;
625
png_ptr->warning_fn=NULL;
627
"Application uses deprecated png_write_init() and should be recompiled.");
631
} while (png_libpng_ver[i++]);
633
png_debug(1, "in png_write_init_3\n");
635
#ifdef PNG_SETJMP_SUPPORTED
636
/* save jump buffer and error functions */
637
png_memcpy(tmp_jmp, png_ptr->jmpbuf, png_sizeof (jmp_buf));
640
if (png_sizeof(png_struct) > png_struct_size)
642
png_destroy_struct(png_ptr);
643
png_ptr = (png_structp)png_create_struct(PNG_STRUCT_PNG);
647
/* reset all variables to 0 */
648
png_memset(png_ptr, 0, png_sizeof (png_struct));
650
/* added at libpng-1.2.6 */
651
#ifdef PNG_SET_USER_LIMITS_SUPPORTED
652
png_ptr->user_width_max=PNG_USER_WIDTH_MAX;
653
png_ptr->user_height_max=PNG_USER_HEIGHT_MAX;
656
#if !defined(PNG_1_0_X)
657
#ifdef PNG_ASSEMBLER_CODE_SUPPORTED
658
png_init_mmx_flags(png_ptr); /* 1.2.0 addition */
660
#endif /* PNG_1_0_X */
662
#ifdef PNG_SETJMP_SUPPORTED
663
/* restore jump buffer */
664
png_memcpy(png_ptr->jmpbuf, tmp_jmp, png_sizeof (jmp_buf));
667
png_set_write_fn(png_ptr, png_voidp_NULL, png_rw_ptr_NULL,
670
/* initialize zbuf - compression buffer */
671
png_ptr->zbuf_size = PNG_ZBUF_SIZE;
672
png_ptr->zbuf = (png_bytep)png_malloc(png_ptr,
673
(png_uint_32)png_ptr->zbuf_size);
675
#if defined(PNG_WRITE_WEIGHTED_FILTER_SUPPORTED)
676
png_set_filter_heuristics(png_ptr, PNG_FILTER_HEURISTIC_DEFAULT,
677
1, png_doublep_NULL, png_doublep_NULL);
681
/* Write a few rows of image data. If the image is interlaced,
682
* either you will have to write the 7 sub images, or, if you
683
* have called png_set_interlace_handling(), you will have to
684
* "write" the image seven times.
687
png_write_rows(png_structp png_ptr, png_bytepp row,
688
png_uint_32 num_rows)
690
png_uint_32 i; /* row counter */
691
png_bytepp rp; /* row pointer */
693
png_debug(1, "in png_write_rows\n");
694
/* loop through the rows */
695
for (i = 0, rp = row; i < num_rows; i++, rp++)
697
png_write_row(png_ptr, *rp);
701
/* Write the image. You only need to call this function once, even
702
* if you are writing an interlaced image.
705
png_write_image(png_structp png_ptr, png_bytepp image)
707
png_uint_32 i; /* row index */
708
int pass, num_pass; /* pass variables */
709
png_bytepp rp; /* points to current row */
711
png_debug(1, "in png_write_image\n");
712
#if defined(PNG_WRITE_INTERLACING_SUPPORTED)
713
/* intialize interlace handling. If image is not interlaced,
714
this will set pass to 1 */
715
num_pass = png_set_interlace_handling(png_ptr);
719
/* loop through passes */
720
for (pass = 0; pass < num_pass; pass++)
722
/* loop through image */
723
for (i = 0, rp = image; i < png_ptr->height; i++, rp++)
725
png_write_row(png_ptr, *rp);
730
/* called by user to write a row of image data */
732
png_write_row(png_structp png_ptr, png_bytep row)
734
png_debug2(1, "in png_write_row (row %ld, pass %d)\n",
735
png_ptr->row_number, png_ptr->pass);
736
/* initialize transformations and other stuff if first time */
737
if (png_ptr->row_number == 0 && png_ptr->pass == 0)
739
/* make sure we wrote the header info */
740
if (!(png_ptr->mode & PNG_WROTE_INFO_BEFORE_PLTE))
742
"png_write_info was never called before png_write_row.");
744
/* check for transforms that have been set but were defined out */
745
#if !defined(PNG_WRITE_INVERT_SUPPORTED) && defined(PNG_READ_INVERT_SUPPORTED)
746
if (png_ptr->transformations & PNG_INVERT_MONO)
747
png_warning(png_ptr, "PNG_WRITE_INVERT_SUPPORTED is not defined.");
749
#if !defined(PNG_WRITE_FILLER_SUPPORTED) && defined(PNG_READ_FILLER_SUPPORTED)
750
if (png_ptr->transformations & PNG_FILLER)
751
png_warning(png_ptr, "PNG_WRITE_FILLER_SUPPORTED is not defined.");
753
#if !defined(PNG_WRITE_PACKSWAP_SUPPORTED) && defined(PNG_READ_PACKSWAP_SUPPORTED)
754
if (png_ptr->transformations & PNG_PACKSWAP)
755
png_warning(png_ptr, "PNG_WRITE_PACKSWAP_SUPPORTED is not defined.");
757
#if !defined(PNG_WRITE_PACK_SUPPORTED) && defined(PNG_READ_PACK_SUPPORTED)
758
if (png_ptr->transformations & PNG_PACK)
759
png_warning(png_ptr, "PNG_WRITE_PACK_SUPPORTED is not defined.");
761
#if !defined(PNG_WRITE_SHIFT_SUPPORTED) && defined(PNG_READ_SHIFT_SUPPORTED)
762
if (png_ptr->transformations & PNG_SHIFT)
763
png_warning(png_ptr, "PNG_WRITE_SHIFT_SUPPORTED is not defined.");
765
#if !defined(PNG_WRITE_BGR_SUPPORTED) && defined(PNG_READ_BGR_SUPPORTED)
766
if (png_ptr->transformations & PNG_BGR)
767
png_warning(png_ptr, "PNG_WRITE_BGR_SUPPORTED is not defined.");
769
#if !defined(PNG_WRITE_SWAP_SUPPORTED) && defined(PNG_READ_SWAP_SUPPORTED)
770
if (png_ptr->transformations & PNG_SWAP_BYTES)
771
png_warning(png_ptr, "PNG_WRITE_SWAP_SUPPORTED is not defined.");
774
png_write_start_row(png_ptr);
777
#if defined(PNG_WRITE_INTERLACING_SUPPORTED)
778
/* if interlaced and not interested in row, return */
779
if (png_ptr->interlaced && (png_ptr->transformations & PNG_INTERLACE))
781
switch (png_ptr->pass)
784
if (png_ptr->row_number & 0x07)
786
png_write_finish_row(png_ptr);
791
if ((png_ptr->row_number & 0x07) || png_ptr->width < 5)
793
png_write_finish_row(png_ptr);
798
if ((png_ptr->row_number & 0x07) != 4)
800
png_write_finish_row(png_ptr);
805
if ((png_ptr->row_number & 0x03) || png_ptr->width < 3)
807
png_write_finish_row(png_ptr);
812
if ((png_ptr->row_number & 0x03) != 2)
814
png_write_finish_row(png_ptr);
819
if ((png_ptr->row_number & 0x01) || png_ptr->width < 2)
821
png_write_finish_row(png_ptr);
826
if (!(png_ptr->row_number & 0x01))
828
png_write_finish_row(png_ptr);
836
/* set up row info for transformations */
837
png_ptr->row_info.color_type = png_ptr->color_type;
838
png_ptr->row_info.width = png_ptr->usr_width;
839
png_ptr->row_info.channels = png_ptr->usr_channels;
840
png_ptr->row_info.bit_depth = png_ptr->usr_bit_depth;
841
png_ptr->row_info.pixel_depth = (png_byte)(png_ptr->row_info.bit_depth *
842
png_ptr->row_info.channels);
844
png_ptr->row_info.rowbytes = PNG_ROWBYTES(png_ptr->row_info.pixel_depth,
845
png_ptr->row_info.width);
847
png_debug1(3, "row_info->color_type = %d\n", png_ptr->row_info.color_type);
848
png_debug1(3, "row_info->width = %lu\n", png_ptr->row_info.width);
849
png_debug1(3, "row_info->channels = %d\n", png_ptr->row_info.channels);
850
png_debug1(3, "row_info->bit_depth = %d\n", png_ptr->row_info.bit_depth);
851
png_debug1(3, "row_info->pixel_depth = %d\n", png_ptr->row_info.pixel_depth);
852
png_debug1(3, "row_info->rowbytes = %lu\n", png_ptr->row_info.rowbytes);
854
/* Copy user's row into buffer, leaving room for filter byte. */
855
png_memcpy_check(png_ptr, png_ptr->row_buf + 1, row,
856
png_ptr->row_info.rowbytes);
858
#if defined(PNG_WRITE_INTERLACING_SUPPORTED)
859
/* handle interlacing */
860
if (png_ptr->interlaced && png_ptr->pass < 6 &&
861
(png_ptr->transformations & PNG_INTERLACE))
863
png_do_write_interlace(&(png_ptr->row_info),
864
png_ptr->row_buf + 1, png_ptr->pass);
865
/* this should always get caught above, but still ... */
866
if (!(png_ptr->row_info.width))
868
png_write_finish_row(png_ptr);
874
/* handle other transformations */
875
if (png_ptr->transformations)
876
png_do_write_transformations(png_ptr);
878
#if defined(PNG_MNG_FEATURES_SUPPORTED)
879
/* Write filter_method 64 (intrapixel differencing) only if
880
* 1. Libpng was compiled with PNG_MNG_FEATURES_SUPPORTED and
881
* 2. Libpng did not write a PNG signature (this filter_method is only
882
* used in PNG datastreams that are embedded in MNG datastreams) and
883
* 3. The application called png_permit_mng_features with a mask that
884
* included PNG_FLAG_MNG_FILTER_64 and
885
* 4. The filter_method is 64 and
886
* 5. The color_type is RGB or RGBA
888
if((png_ptr->mng_features_permitted & PNG_FLAG_MNG_FILTER_64) &&
889
(png_ptr->filter_type == PNG_INTRAPIXEL_DIFFERENCING))
891
/* Intrapixel differencing */
892
png_do_write_intrapixel(&(png_ptr->row_info), png_ptr->row_buf + 1);
896
/* Find a filter if necessary, filter the row and write it out. */
897
png_write_find_filter(png_ptr, &(png_ptr->row_info));
899
if (png_ptr->write_row_fn != NULL)
900
(*(png_ptr->write_row_fn))(png_ptr, png_ptr->row_number, png_ptr->pass);
903
#if defined(PNG_WRITE_FLUSH_SUPPORTED)
904
/* Set the automatic flush interval or 0 to turn flushing off */
906
png_set_flush(png_structp png_ptr, int nrows)
908
png_debug(1, "in png_set_flush\n");
909
png_ptr->flush_dist = (nrows < 0 ? 0 : nrows);
912
/* flush the current output buffers now */
914
png_write_flush(png_structp png_ptr)
918
png_debug(1, "in png_write_flush\n");
919
/* We have already written out all of the data */
920
if (png_ptr->row_number >= png_ptr->num_rows)
927
/* compress the data */
928
ret = deflate(&png_ptr->zstream, Z_SYNC_FLUSH);
931
/* check for compression errors */
934
if (png_ptr->zstream.msg != NULL)
935
png_error(png_ptr, png_ptr->zstream.msg);
937
png_error(png_ptr, "zlib error");
940
if (!(png_ptr->zstream.avail_out))
942
/* write the IDAT and reset the zlib output buffer */
943
png_write_IDAT(png_ptr, png_ptr->zbuf,
945
png_ptr->zstream.next_out = png_ptr->zbuf;
946
png_ptr->zstream.avail_out = (uInt)png_ptr->zbuf_size;
949
} while(wrote_IDAT == 1);
951
/* If there is any data left to be output, write it into a new IDAT */
952
if (png_ptr->zbuf_size != png_ptr->zstream.avail_out)
954
/* write the IDAT and reset the zlib output buffer */
955
png_write_IDAT(png_ptr, png_ptr->zbuf,
956
png_ptr->zbuf_size - png_ptr->zstream.avail_out);
957
png_ptr->zstream.next_out = png_ptr->zbuf;
958
png_ptr->zstream.avail_out = (uInt)png_ptr->zbuf_size;
960
png_ptr->flush_rows = 0;
963
#endif /* PNG_WRITE_FLUSH_SUPPORTED */
965
/* free all memory used by the write */
967
png_destroy_write_struct(png_structpp png_ptr_ptr, png_infopp info_ptr_ptr)
969
png_structp png_ptr = NULL;
970
png_infop info_ptr = NULL;
971
#ifdef PNG_USER_MEM_SUPPORTED
972
png_free_ptr free_fn = NULL;
973
png_voidp mem_ptr = NULL;
976
png_debug(1, "in png_destroy_write_struct\n");
977
if (png_ptr_ptr != NULL)
979
png_ptr = *png_ptr_ptr;
980
#ifdef PNG_USER_MEM_SUPPORTED
981
free_fn = png_ptr->free_fn;
982
mem_ptr = png_ptr->mem_ptr;
986
if (info_ptr_ptr != NULL)
987
info_ptr = *info_ptr_ptr;
989
if (info_ptr != NULL)
991
png_free_data(png_ptr, info_ptr, PNG_FREE_ALL, -1);
993
#if defined(PNG_UNKNOWN_CHUNKS_SUPPORTED)
994
if (png_ptr->num_chunk_list)
996
png_free(png_ptr, png_ptr->chunk_list);
997
png_ptr->chunk_list=NULL;
998
png_ptr->num_chunk_list=0;
1002
#ifdef PNG_USER_MEM_SUPPORTED
1003
png_destroy_struct_2((png_voidp)info_ptr, (png_free_ptr)free_fn,
1004
(png_voidp)mem_ptr);
1006
png_destroy_struct((png_voidp)info_ptr);
1008
*info_ptr_ptr = NULL;
1011
if (png_ptr != NULL)
1013
png_write_destroy(png_ptr);
1014
#ifdef PNG_USER_MEM_SUPPORTED
1015
png_destroy_struct_2((png_voidp)png_ptr, (png_free_ptr)free_fn,
1016
(png_voidp)mem_ptr);
1018
png_destroy_struct((png_voidp)png_ptr);
1020
*png_ptr_ptr = NULL;
1025
/* Free any memory used in png_ptr struct (old method) */
1027
png_write_destroy(png_structp png_ptr)
1029
#ifdef PNG_SETJMP_SUPPORTED
1030
jmp_buf tmp_jmp; /* save jump buffer */
1032
png_error_ptr error_fn;
1033
png_error_ptr warning_fn;
1034
png_voidp error_ptr;
1035
#ifdef PNG_USER_MEM_SUPPORTED
1036
png_free_ptr free_fn;
1039
png_debug(1, "in png_write_destroy\n");
1040
/* free any memory zlib uses */
1041
deflateEnd(&png_ptr->zstream);
1043
/* free our memory. png_free checks NULL for us. */
1044
png_free(png_ptr, png_ptr->zbuf);
1045
png_free(png_ptr, png_ptr->row_buf);
1046
png_free(png_ptr, png_ptr->prev_row);
1047
png_free(png_ptr, png_ptr->sub_row);
1048
png_free(png_ptr, png_ptr->up_row);
1049
png_free(png_ptr, png_ptr->avg_row);
1050
png_free(png_ptr, png_ptr->paeth_row);
1052
#if defined(PNG_TIME_RFC1123_SUPPORTED)
1053
png_free(png_ptr, png_ptr->time_buffer);
1056
#if defined(PNG_WRITE_WEIGHTED_FILTER_SUPPORTED)
1057
png_free(png_ptr, png_ptr->prev_filters);
1058
png_free(png_ptr, png_ptr->filter_weights);
1059
png_free(png_ptr, png_ptr->inv_filter_weights);
1060
png_free(png_ptr, png_ptr->filter_costs);
1061
png_free(png_ptr, png_ptr->inv_filter_costs);
1064
#ifdef PNG_SETJMP_SUPPORTED
1065
/* reset structure */
1066
png_memcpy(tmp_jmp, png_ptr->jmpbuf, png_sizeof (jmp_buf));
1069
error_fn = png_ptr->error_fn;
1070
warning_fn = png_ptr->warning_fn;
1071
error_ptr = png_ptr->error_ptr;
1072
#ifdef PNG_USER_MEM_SUPPORTED
1073
free_fn = png_ptr->free_fn;
1076
png_memset(png_ptr, 0, png_sizeof (png_struct));
1078
png_ptr->error_fn = error_fn;
1079
png_ptr->warning_fn = warning_fn;
1080
png_ptr->error_ptr = error_ptr;
1081
#ifdef PNG_USER_MEM_SUPPORTED
1082
png_ptr->free_fn = free_fn;
1085
#ifdef PNG_SETJMP_SUPPORTED
1086
png_memcpy(png_ptr->jmpbuf, tmp_jmp, png_sizeof (jmp_buf));
1090
/* Allow the application to select one or more row filters to use. */
1092
png_set_filter(png_structp png_ptr, int method, int filters)
1094
png_debug(1, "in png_set_filter\n");
1095
#if defined(PNG_MNG_FEATURES_SUPPORTED)
1096
if((png_ptr->mng_features_permitted & PNG_FLAG_MNG_FILTER_64) &&
1097
(method == PNG_INTRAPIXEL_DIFFERENCING))
1098
method = PNG_FILTER_TYPE_BASE;
1100
if (method == PNG_FILTER_TYPE_BASE)
1102
switch (filters & (PNG_ALL_FILTERS | 0x07))
1106
case 7: png_warning(png_ptr, "Unknown row filter for method 0");
1107
case PNG_FILTER_VALUE_NONE: png_ptr->do_filter=PNG_FILTER_NONE; break;
1108
case PNG_FILTER_VALUE_SUB: png_ptr->do_filter=PNG_FILTER_SUB; break;
1109
case PNG_FILTER_VALUE_UP: png_ptr->do_filter=PNG_FILTER_UP; break;
1110
case PNG_FILTER_VALUE_AVG: png_ptr->do_filter=PNG_FILTER_AVG; break;
1111
case PNG_FILTER_VALUE_PAETH: png_ptr->do_filter=PNG_FILTER_PAETH;break;
1112
default: png_ptr->do_filter = (png_byte)filters; break;
1115
/* If we have allocated the row_buf, this means we have already started
1116
* with the image and we should have allocated all of the filter buffers
1117
* that have been selected. If prev_row isn't already allocated, then
1118
* it is too late to start using the filters that need it, since we
1119
* will be missing the data in the previous row. If an application
1120
* wants to start and stop using particular filters during compression,
1121
* it should start out with all of the filters, and then add and
1122
* remove them after the start of compression.
1124
if (png_ptr->row_buf != NULL)
1126
if ((png_ptr->do_filter & PNG_FILTER_SUB) && png_ptr->sub_row == NULL)
1128
png_ptr->sub_row = (png_bytep)png_malloc(png_ptr,
1129
(png_ptr->rowbytes + 1));
1130
png_ptr->sub_row[0] = PNG_FILTER_VALUE_SUB;
1133
if ((png_ptr->do_filter & PNG_FILTER_UP) && png_ptr->up_row == NULL)
1135
if (png_ptr->prev_row == NULL)
1137
png_warning(png_ptr, "Can't add Up filter after starting");
1138
png_ptr->do_filter &= ~PNG_FILTER_UP;
1142
png_ptr->up_row = (png_bytep)png_malloc(png_ptr,
1143
(png_ptr->rowbytes + 1));
1144
png_ptr->up_row[0] = PNG_FILTER_VALUE_UP;
1148
if ((png_ptr->do_filter & PNG_FILTER_AVG) && png_ptr->avg_row == NULL)
1150
if (png_ptr->prev_row == NULL)
1152
png_warning(png_ptr, "Can't add Average filter after starting");
1153
png_ptr->do_filter &= ~PNG_FILTER_AVG;
1157
png_ptr->avg_row = (png_bytep)png_malloc(png_ptr,
1158
(png_ptr->rowbytes + 1));
1159
png_ptr->avg_row[0] = PNG_FILTER_VALUE_AVG;
1163
if ((png_ptr->do_filter & PNG_FILTER_PAETH) &&
1164
png_ptr->paeth_row == NULL)
1166
if (png_ptr->prev_row == NULL)
1168
png_warning(png_ptr, "Can't add Paeth filter after starting");
1169
png_ptr->do_filter &= (png_byte)(~PNG_FILTER_PAETH);
1173
png_ptr->paeth_row = (png_bytep)png_malloc(png_ptr,
1174
(png_ptr->rowbytes + 1));
1175
png_ptr->paeth_row[0] = PNG_FILTER_VALUE_PAETH;
1179
if (png_ptr->do_filter == PNG_NO_FILTERS)
1180
png_ptr->do_filter = PNG_FILTER_NONE;
1184
png_error(png_ptr, "Unknown custom filter method");
1187
/* This allows us to influence the way in which libpng chooses the "best"
1188
* filter for the current scanline. While the "minimum-sum-of-absolute-
1189
* differences metric is relatively fast and effective, there is some
1190
* question as to whether it can be improved upon by trying to keep the
1191
* filtered data going to zlib more consistent, hopefully resulting in
1192
* better compression.
1194
#if defined(PNG_WRITE_WEIGHTED_FILTER_SUPPORTED) /* GRR 970116 */
1196
png_set_filter_heuristics(png_structp png_ptr, int heuristic_method,
1197
int num_weights, png_doublep filter_weights,
1198
png_doublep filter_costs)
1202
png_debug(1, "in png_set_filter_heuristics\n");
1203
if (heuristic_method >= PNG_FILTER_HEURISTIC_LAST)
1205
png_warning(png_ptr, "Unknown filter heuristic method");
1209
if (heuristic_method == PNG_FILTER_HEURISTIC_DEFAULT)
1211
heuristic_method = PNG_FILTER_HEURISTIC_UNWEIGHTED;
1214
if (num_weights < 0 || filter_weights == NULL ||
1215
heuristic_method == PNG_FILTER_HEURISTIC_UNWEIGHTED)
1220
png_ptr->num_prev_filters = (png_byte)num_weights;
1221
png_ptr->heuristic_method = (png_byte)heuristic_method;
1223
if (num_weights > 0)
1225
if (png_ptr->prev_filters == NULL)
1227
png_ptr->prev_filters = (png_bytep)png_malloc(png_ptr,
1228
(png_uint_32)(png_sizeof(png_byte) * num_weights));
1230
/* To make sure that the weighting starts out fairly */
1231
for (i = 0; i < num_weights; i++)
1233
png_ptr->prev_filters[i] = 255;
1237
if (png_ptr->filter_weights == NULL)
1239
png_ptr->filter_weights = (png_uint_16p)png_malloc(png_ptr,
1240
(png_uint_32)(png_sizeof(png_uint_16) * num_weights));
1242
png_ptr->inv_filter_weights = (png_uint_16p)png_malloc(png_ptr,
1243
(png_uint_32)(png_sizeof(png_uint_16) * num_weights));
1244
for (i = 0; i < num_weights; i++)
1246
png_ptr->inv_filter_weights[i] =
1247
png_ptr->filter_weights[i] = PNG_WEIGHT_FACTOR;
1251
for (i = 0; i < num_weights; i++)
1253
if (filter_weights[i] < 0.0)
1255
png_ptr->inv_filter_weights[i] =
1256
png_ptr->filter_weights[i] = PNG_WEIGHT_FACTOR;
1260
png_ptr->inv_filter_weights[i] =
1261
(png_uint_16)((double)PNG_WEIGHT_FACTOR*filter_weights[i]+0.5);
1262
png_ptr->filter_weights[i] =
1263
(png_uint_16)((double)PNG_WEIGHT_FACTOR/filter_weights[i]+0.5);
1268
/* If, in the future, there are other filter methods, this would
1269
* need to be based on png_ptr->filter.
1271
if (png_ptr->filter_costs == NULL)
1273
png_ptr->filter_costs = (png_uint_16p)png_malloc(png_ptr,
1274
(png_uint_32)(png_sizeof(png_uint_16) * PNG_FILTER_VALUE_LAST));
1276
png_ptr->inv_filter_costs = (png_uint_16p)png_malloc(png_ptr,
1277
(png_uint_32)(png_sizeof(png_uint_16) * PNG_FILTER_VALUE_LAST));
1279
for (i = 0; i < PNG_FILTER_VALUE_LAST; i++)
1281
png_ptr->inv_filter_costs[i] =
1282
png_ptr->filter_costs[i] = PNG_COST_FACTOR;
1286
/* Here is where we set the relative costs of the different filters. We
1287
* should take the desired compression level into account when setting
1288
* the costs, so that Paeth, for instance, has a high relative cost at low
1289
* compression levels, while it has a lower relative cost at higher
1290
* compression settings. The filter types are in order of increasing
1291
* relative cost, so it would be possible to do this with an algorithm.
1293
for (i = 0; i < PNG_FILTER_VALUE_LAST; i++)
1295
if (filter_costs == NULL || filter_costs[i] < 0.0)
1297
png_ptr->inv_filter_costs[i] =
1298
png_ptr->filter_costs[i] = PNG_COST_FACTOR;
1300
else if (filter_costs[i] >= 1.0)
1302
png_ptr->inv_filter_costs[i] =
1303
(png_uint_16)((double)PNG_COST_FACTOR / filter_costs[i] + 0.5);
1304
png_ptr->filter_costs[i] =
1305
(png_uint_16)((double)PNG_COST_FACTOR * filter_costs[i] + 0.5);
1309
#endif /* PNG_WRITE_WEIGHTED_FILTER_SUPPORTED */
1312
png_set_compression_level(png_structp png_ptr, int level)
1314
png_debug(1, "in png_set_compression_level\n");
1315
png_ptr->flags |= PNG_FLAG_ZLIB_CUSTOM_LEVEL;
1316
png_ptr->zlib_level = level;
1320
png_set_compression_mem_level(png_structp png_ptr, int mem_level)
1322
png_debug(1, "in png_set_compression_mem_level\n");
1323
png_ptr->flags |= PNG_FLAG_ZLIB_CUSTOM_MEM_LEVEL;
1324
png_ptr->zlib_mem_level = mem_level;
1328
png_set_compression_strategy(png_structp png_ptr, int strategy)
1330
png_debug(1, "in png_set_compression_strategy\n");
1331
png_ptr->flags |= PNG_FLAG_ZLIB_CUSTOM_STRATEGY;
1332
png_ptr->zlib_strategy = strategy;
1336
png_set_compression_window_bits(png_structp png_ptr, int window_bits)
1338
if (window_bits > 15)
1339
png_warning(png_ptr, "Only compression windows <= 32k supported by PNG");
1340
else if (window_bits < 8)
1341
png_warning(png_ptr, "Only compression windows >= 256 supported by PNG");
1343
/* avoid libpng bug with 256-byte windows */
1344
if (window_bits == 8)
1346
png_warning(png_ptr, "Compression window is being reset to 512");
1350
png_ptr->flags |= PNG_FLAG_ZLIB_CUSTOM_WINDOW_BITS;
1351
png_ptr->zlib_window_bits = window_bits;
1355
png_set_compression_method(png_structp png_ptr, int method)
1357
png_debug(1, "in png_set_compression_method\n");
1359
png_warning(png_ptr, "Only compression method 8 is supported by PNG");
1360
png_ptr->flags |= PNG_FLAG_ZLIB_CUSTOM_METHOD;
1361
png_ptr->zlib_method = method;
1365
png_set_write_status_fn(png_structp png_ptr, png_write_status_ptr write_row_fn)
1367
png_ptr->write_row_fn = write_row_fn;
1370
#if defined(PNG_WRITE_USER_TRANSFORM_SUPPORTED)
1372
png_set_write_user_transform_fn(png_structp png_ptr, png_user_transform_ptr
1373
write_user_transform_fn)
1375
png_debug(1, "in png_set_write_user_transform_fn\n");
1376
png_ptr->transformations |= PNG_USER_TRANSFORM;
1377
png_ptr->write_user_transform_fn = write_user_transform_fn;
1382
#if defined(PNG_INFO_IMAGE_SUPPORTED)
1384
png_write_png(png_structp png_ptr, png_infop info_ptr,
1385
int transforms, voidp params)
1387
#if defined(PNG_WRITE_INVERT_ALPHA_SUPPORTED)
1388
/* invert the alpha channel from opacity to transparency */
1389
if (transforms & PNG_TRANSFORM_INVERT_ALPHA)
1390
png_set_invert_alpha(png_ptr);
1393
/* Write the file header information. */
1394
png_write_info(png_ptr, info_ptr);
1396
/* ------ these transformations don't touch the info structure ------- */
1398
#if defined(PNG_WRITE_INVERT_SUPPORTED)
1399
/* invert monochrome pixels */
1400
if (transforms & PNG_TRANSFORM_INVERT_MONO)
1401
png_set_invert_mono(png_ptr);
1404
#if defined(PNG_WRITE_SHIFT_SUPPORTED)
1405
/* Shift the pixels up to a legal bit depth and fill in
1406
* as appropriate to correctly scale the image.
1408
if ((transforms & PNG_TRANSFORM_SHIFT)
1409
&& (info_ptr->valid & PNG_INFO_sBIT))
1410
png_set_shift(png_ptr, &info_ptr->sig_bit);
1413
#if defined(PNG_WRITE_PACK_SUPPORTED)
1414
/* pack pixels into bytes */
1415
if (transforms & PNG_TRANSFORM_PACKING)
1416
png_set_packing(png_ptr);
1419
#if defined(PNG_WRITE_SWAP_ALPHA_SUPPORTED)
1420
/* swap location of alpha bytes from ARGB to RGBA */
1421
if (transforms & PNG_TRANSFORM_SWAP_ALPHA)
1422
png_set_swap_alpha(png_ptr);
1425
#if defined(PNG_WRITE_FILLER_SUPPORTED)
1426
/* Get rid of filler (OR ALPHA) bytes, pack XRGB/RGBX/ARGB/RGBA into
1427
* RGB (4 channels -> 3 channels). The second parameter is not used.
1429
if (transforms & PNG_TRANSFORM_STRIP_FILLER)
1430
png_set_filler(png_ptr, 0, PNG_FILLER_BEFORE);
1433
#if defined(PNG_WRITE_BGR_SUPPORTED)
1434
/* flip BGR pixels to RGB */
1435
if (transforms & PNG_TRANSFORM_BGR)
1436
png_set_bgr(png_ptr);
1439
#if defined(PNG_WRITE_SWAP_SUPPORTED)
1440
/* swap bytes of 16-bit files to most significant byte first */
1441
if (transforms & PNG_TRANSFORM_SWAP_ENDIAN)
1442
png_set_swap(png_ptr);
1445
#if defined(PNG_WRITE_PACKSWAP_SUPPORTED)
1446
/* swap bits of 1, 2, 4 bit packed pixel formats */
1447
if (transforms & PNG_TRANSFORM_PACKSWAP)
1448
png_set_packswap(png_ptr);
1451
/* ----------------------- end of transformations ------------------- */
1453
/* write the bits */
1454
if (info_ptr->valid & PNG_INFO_IDAT)
1455
png_write_image(png_ptr, info_ptr->row_pointers);
1457
/* It is REQUIRED to call this to finish writing the rest of the file */
1458
png_write_end(png_ptr, info_ptr);
1460
if(transforms == 0 || params == NULL)
1461
/* quiet compiler warnings */ return;
1464
#endif /* PNG_WRITE_SUPPORTED */
added
removed
src/lib/lpng/pngwrite.c
