1
/* png.h - header file for PNG reference library
3
* libpng version 1.2.7 - September 12, 2004
4
* Copyright (c) 1998-2004 Glenn Randers-Pehrson
5
* (Version 0.96 Copyright (c) 1996, 1997 Andreas Dilger)
6
* (Version 0.88 Copyright (c) 1995, 1996 Guy Eric Schalnat, Group 42, Inc.)
8
* Authors and maintainers:
9
* libpng versions 0.71, May 1995, through 0.88, January 1996: Guy Schalnat
10
* libpng versions 0.89c, June 1996, through 0.96, May 1997: Andreas Dilger
11
* libpng versions 0.97, January 1998, through 1.2.7 - September 12, 2004: Glenn
12
* See also "Contributing Authors", below.
14
* Note about libpng version numbers:
16
* Due to various miscommunications, unforeseen code incompatibilities
17
* and occasional factors outside the authors' control, version numbering
18
* on the library has not always been consistent and straightforward.
19
* The following table summarizes matters since version 0.89c, which was
20
* the first widely used release:
22
* source png.h png.h shared-lib
23
* version string int version
24
* ------- ------ ----- ----------
25
* 0.89c "1.0 beta 3" 0.89 89 1.0.89
26
* 0.90 "1.0 beta 4" 0.90 90 0.90 [should have been 2.0.90]
27
* 0.95 "1.0 beta 5" 0.95 95 0.95 [should have been 2.0.95]
28
* 0.96 "1.0 beta 6" 0.96 96 0.96 [should have been 2.0.96]
29
* 0.97b "1.00.97 beta 7" 1.00.97 97 1.0.1 [should have been 2.0.97]
30
* 0.97c 0.97 97 2.0.97
33
* 0.99a-m 0.99 99 2.0.99
34
* 1.00 1.00 100 2.1.0 [100 should be 10000]
35
* 1.0.0 (from here on, the 100 2.1.0 [100 should be 10000]
36
* 1.0.1 png.h string is 10001 2.1.0
37
* 1.0.1a-e identical to the 10002 from here on, the shared library
38
* 1.0.2 source version) 10002 is 2.V where V is the source code
39
* 1.0.2a-b 10003 version, except as noted.
44
* 1.0.5 (+ 2 patches) 10005
46
* 1.0.5e-r 10100 (not source compatible)
47
* 1.0.5s-v 10006 (not binary compatible)
48
* 1.0.6 (+ 3 patches) 10006 (still binary incompatible)
49
* 1.0.6d-f 10007 (still binary incompatible)
51
* 1.0.6h 10007 10.6h (testing xy.z so-numbering)
53
* 1.0.6j 10007 2.1.0.6j (incompatible with 1.0.0)
54
* 1.0.7beta11-14 DLLNUM 10007 2.1.0.7beta11-14 (binary compatible)
55
* 1.0.7beta15-18 1 10007 2.1.0.7beta15-18 (binary compatible)
56
* 1.0.7rc1-2 1 10007 2.1.0.7rc1-2 (binary compatible)
57
* 1.0.7 1 10007 (still compatible)
58
* 1.0.8beta1-4 1 10008 2.1.0.8beta1-4
59
* 1.0.8rc1 1 10008 2.1.0.8rc1
60
* 1.0.8 1 10008 2.1.0.8
61
* 1.0.9beta1-6 1 10009 2.1.0.9beta1-6
62
* 1.0.9rc1 1 10009 2.1.0.9rc1
63
* 1.0.9beta7-10 1 10009 2.1.0.9beta7-10
64
* 1.0.9rc2 1 10009 2.1.0.9rc2
65
* 1.0.9 1 10009 2.1.0.9
66
* 1.0.10beta1 1 10010 2.1.0.10beta1
67
* 1.0.10rc1 1 10010 2.1.0.10rc1
68
* 1.0.10 1 10010 2.1.0.10
69
* 1.0.11beta1-3 1 10011 2.1.0.11beta1-3
70
* 1.0.11rc1 1 10011 2.1.0.11rc1
71
* 1.0.11 1 10011 2.1.0.11
72
* 1.0.12beta1-2 2 10012 2.1.0.12beta1-2
73
* 1.0.12rc1 2 10012 2.1.0.12rc1
74
* 1.0.12 2 10012 2.1.0.12
75
* 1.1.0a-f - 10100 2.1.1.0a-f (branch abandoned)
76
* 1.2.0beta1-2 2 10200 2.1.2.0beta1-2
77
* 1.2.0beta3-5 3 10200 3.1.2.0beta3-5
78
* 1.2.0rc1 3 10200 3.1.2.0rc1
79
* 1.2.0 3 10200 3.1.2.0
80
* 1.2.1beta1-4 3 10201 3.1.2.1beta1-4
81
* 1.2.1rc1-2 3 10201 3.1.2.1rc1-2
82
* 1.2.1 3 10201 3.1.2.1
83
* 1.2.2beta1-6 12 10202 12.so.0.1.2.2beta1-6
84
* 1.0.13beta1 10 10013 10.so.0.1.0.13beta1
85
* 1.0.13rc1 10 10013 10.so.0.1.0.13rc1
86
* 1.2.2rc1 12 10202 12.so.0.1.2.2rc1
87
* 1.0.13 10 10013 10.so.0.1.0.13
88
* 1.2.2 12 10202 12.so.0.1.2.2
89
* 1.2.3rc1-6 12 10203 12.so.0.1.2.3rc1-6
90
* 1.2.3 12 10203 12.so.0.1.2.3
91
* 1.2.4beta1-3 13 10204 12.so.0.1.2.4beta1-3
92
* 1.0.14rc1 13 10014 10.so.0.1.0.14rc1
93
* 1.2.4rc1 13 10204 12.so.0.1.2.4rc1
94
* 1.0.14 10 10014 10.so.0.1.0.14
95
* 1.2.4 13 10204 12.so.0.1.2.4
96
* 1.2.5beta1-2 13 10205 12.so.0.1.2.5beta1-2
97
* 1.0.15rc1-3 10 10015 10.so.0.1.0.15rc1-3
98
* 1.2.5rc1-3 13 10205 12.so.0.1.2.5rc1-3
99
* 1.0.15 10 10015 10.so.0.1.0.15
100
* 1.2.5 13 10205 12.so.0.1.2.5
101
* 1.2.6beta1-4 13 10206 12.so.0.1.2.6beta1-4
102
* 1.0.16 10 10016 10.so.0.1.0.16
103
* 1.2.6 13 10206 12.so.0.1.2.6
104
* 1.2.7beta1-2 13 10207 12.so.0.1.2.7beta1-2
105
* 1.0.17rc1 10 10017 12.so.0.1.0.17rc1
106
* 1.2.7rc1 13 10207 12.so.0.1.2.7rc1
107
* 1.0.17 10 10017 12.so.0.1.0.17
108
* 1.2.7 13 10207 12.so.0.1.2.7
110
* Henceforth the source version will match the shared-library major
111
* and minor numbers; the shared-library major version number will be
112
* used for changes in backward compatibility, as it is intended. The
113
* PNG_LIBPNG_VER macro, which is not used within libpng but is available
114
* for applications, is an unsigned integer of the form xyyzz corresponding
115
* to the source version x.y.z (leading zeros in y and z). Beta versions
116
* were given the previous public release number plus a letter, until
117
* version 1.0.6j; from then on they were given the upcoming public
118
* release number plus "betaNN" or "rcN".
120
* Binary incompatibility exists only when applications make direct access
121
* to the info_ptr or png_ptr members through png.h, and the compiled
122
* application is loaded with a different version of the library.
124
* DLLNUM will change each time there are forward or backward changes
125
* in binary compatibility (e.g., when a new feature is added).
127
* See libpng.txt or libpng.3 for more information. The PNG specification
128
* is available as a W3C Recommendation and as an ISO Specification,
129
* <http://www.w3.org/TR/2003/REC-PNG-20031110/
133
* COPYRIGHT NOTICE, DISCLAIMER, and LICENSE:
135
* If you modify libpng you may insert additional notices immediately following
138
* libpng versions 1.2.6, August 15, 2004, through 1.2.7, September 12, 2004, are
139
* Copyright (c) 2004 Glenn Randers-Pehrson, and are
140
* distributed according to the same disclaimer and license as libpng-1.2.5
141
* with the following individual added to the list of Contributing Authors:
145
* libpng versions 1.0.7, July 1, 2000, through 1.2.5, October 3, 2002, are
146
* Copyright (c) 2000-2002 Glenn Randers-Pehrson, and are
147
* distributed according to the same disclaimer and license as libpng-1.0.6
148
* with the following individuals added to the list of Contributing Authors:
150
* Simon-Pierre Cadieux
154
* and with the following additions to the disclaimer:
156
* There is no warranty against interference with your enjoyment of the
157
* library or against infringement. There is no warranty that our
158
* efforts or the library will fulfill any of your particular purposes
159
* or needs. This library is provided with all faults, and the entire
160
* risk of satisfactory quality, performance, accuracy, and effort is with
163
* libpng versions 0.97, January 1998, through 1.0.6, March 20, 2000, are
164
* Copyright (c) 1998, 1999, 2000 Glenn Randers-Pehrson, and are
165
* distributed according to the same disclaimer and license as libpng-0.96,
166
* with the following individuals added to the list of Contributing Authors:
169
* Glenn Randers-Pehrson
172
* libpng versions 0.89, June 1996, through 0.96, May 1997, are
173
* Copyright (c) 1996, 1997 Andreas Dilger
174
* Distributed according to the same disclaimer and license as libpng-0.88,
175
* with the following individuals added to the list of Contributing Authors:
184
* libpng versions 0.5, May 1995, through 0.88, January 1996, are
185
* Copyright (c) 1995, 1996 Guy Eric Schalnat, Group 42, Inc.
187
* For the purposes of this copyright and license, "Contributing Authors"
188
* is defined as the following set of individuals:
196
* The PNG Reference Library is supplied "AS IS". The Contributing Authors
197
* and Group 42, Inc. disclaim all warranties, expressed or implied,
198
* including, without limitation, the warranties of merchantability and of
199
* fitness for any purpose. The Contributing Authors and Group 42, Inc.
200
* assume no liability for direct, indirect, incidental, special, exemplary,
201
* or consequential damages, which may result from the use of the PNG
202
* Reference Library, even if advised of the possibility of such damage.
204
* Permission is hereby granted to use, copy, modify, and distribute this
205
* source code, or portions hereof, for any purpose, without fee, subject
206
* to the following restrictions:
208
* 1. The origin of this source code must not be misrepresented.
210
* 2. Altered versions must be plainly marked as such and
211
* must not be misrepresented as being the original source.
213
* 3. This Copyright notice may not be removed or altered from
214
* any source or altered source distribution.
216
* The Contributing Authors and Group 42, Inc. specifically permit, without
217
* fee, and encourage the use of this source code as a component to
218
* supporting the PNG file format in commercial products. If you use this
219
* source code in a product, acknowledgment is not required but would be
224
* A "png_get_copyright" function is available, for convenient use in "about"
225
* boxes and the like:
227
* printf("%s",png_get_copyright(NULL));
229
* Also, the PNG logo (in PNG format, of course) is supplied in the
230
* files "pngbar.png" and "pngbar.jpg (88x31) and "pngnow.png" (98x31).
234
* Libpng is OSI Certified Open Source Software. OSI Certified is a
235
* certification mark of the Open Source Initiative.
239
* The contributing authors would like to thank all those who helped
240
* with testing, bug fixes, and patience. This wouldn't have been
241
* possible without all of you.
243
* Thanks to Frank J. T. Wojcik for helping with the documentation.
247
* Y2K compliance in libpng:
248
* =========================
252
* Since the PNG Development group is an ad-hoc body, we can't make
253
* an official declaration.
255
* This is your unofficial assurance that libpng from version 0.71 and
256
* upward through 1.2.7 are Y2K compliant. It is my belief that earlier
257
* versions were also Y2K compliant.
259
* Libpng only has three year fields. One is a 2-byte unsigned integer
260
* that will hold years up to 65535. The other two hold the date in text
261
* format, and will hold years up to 9999.
264
* "png_uint_16 year" in png_time_struct.
267
* "png_charp time_buffer" in png_struct and
268
* "near_time_buffer", which is a local character string in png.c.
270
* There are seven time-related functions:
271
* png.c: png_convert_to_rfc_1123() in png.c
272
* (formerly png_convert_to_rfc_1152() in error)
273
* png_convert_from_struct_tm() in pngwrite.c, called in pngwrite.c
274
* png_convert_from_time_t() in pngwrite.c
275
* png_get_tIME() in pngget.c
276
* png_handle_tIME() in pngrutil.c, called in pngread.c
277
* png_set_tIME() in pngset.c
278
* png_write_tIME() in pngwutil.c, called in pngwrite.c
280
* All handle dates properly in a Y2K environment. The
281
* png_convert_from_time_t() function calls gmtime() to convert from system
282
* clock time, which returns (year - 1900), which we properly convert to
283
* the full 4-digit year. There is a possibility that applications using
284
* libpng are not passing 4-digit years into the png_convert_to_rfc_1123()
285
* function, or that they are incorrectly passing only a 2-digit year
286
* instead of "year - 1900" into the png_convert_from_struct_tm() function,
287
* but this is not under our control. The libpng documentation has always
288
* stated that it works with 4-digit years, and the APIs have been
289
* documented as such.
291
* The tIME chunk itself is also Y2K compliant. It uses a 2-byte unsigned
292
* integer to hold the year, and can hold years as large as 65535.
294
* zlib, upon which libpng depends, is also Y2K compliant. It contains
295
* no date-related code.
297
* Glenn Randers-Pehrson
299
* PNG Development Group
305
/* This is not the place to learn how to use libpng. The file libpng.txt
306
* describes how to use libpng, and the file example.c summarizes it
307
* with some code on which to build. This file is useful for looking
308
* at the actual function definitions and structure components.
311
/* Version information for png.h - this should match the version in png.c */
312
#define PNG_LIBPNG_VER_STRING "1.2.7"
313
#define PNG_HEADER_VERSION_STRING \
314
" libpng version 1.2.7 - September 12, 2004 (header)\n"
316
#define PNG_LIBPNG_VER_SONUM 0
317
#define PNG_LIBPNG_VER_DLLNUM %DLLNUM%
319
/* These should match the first 3 components of PNG_LIBPNG_VER_STRING: */
320
#define PNG_LIBPNG_VER_MAJOR 1
321
#define PNG_LIBPNG_VER_MINOR 2
322
#define PNG_LIBPNG_VER_RELEASE 7
323
/* This should match the numeric part of the final component of
324
* PNG_LIBPNG_VER_STRING, omitting any leading zero: */
326
#define PNG_LIBPNG_VER_BUILD 0
328
#define PNG_LIBPNG_BUILD_ALPHA 1
329
#define PNG_LIBPNG_BUILD_BETA 2
330
#define PNG_LIBPNG_BUILD_RC 3
331
#define PNG_LIBPNG_BUILD_STABLE 4
332
#define PNG_LIBPNG_BUILD_TYPEMASK 7
333
#define PNG_LIBPNG_BUILD_PATCH 8 /* Can be OR'ed with STABLE only */
334
#define PNG_LIBPNG_BUILD_TYPE 4
336
/* Careful here. At one time, Guy wanted to use 082, but that would be octal.
337
* We must not include leading zeros.
338
* Versions 0.7 through 1.0.0 were in the range 0 to 100 here (only
339
* version 1.0.0 was mis-numbered 100 instead of 10000). From
340
* version 1.0.1 it's xxyyzz, where x=major, y=minor, z=release */
341
#define PNG_LIBPNG_VER 10207 /* 1.2.7 */
343
#ifndef PNG_VERSION_INFO_ONLY
345
/* include the compression library's header */
348
/* include all user configurable info, including optional assembler routines */
351
/* Inhibit C++ name-mangling for libpng functions but not for system calls. */
354
#endif /* __cplusplus */
356
/* This file is arranged in several sections. The first section contains
357
* structure and type definitions. The second section contains the external
358
* library functions, while the third has the internal library functions,
359
* which applications aren't expected to use directly.
362
#ifndef PNG_NO_TYPECAST_NULL
363
#define int_p_NULL (int *)NULL
364
#define png_bytep_NULL (png_bytep)NULL
365
#define png_bytepp_NULL (png_bytepp)NULL
366
#define png_doublep_NULL (png_doublep)NULL
367
#define png_error_ptr_NULL (png_error_ptr)NULL
368
#define png_flush_ptr_NULL (png_flush_ptr)NULL
369
#define png_free_ptr_NULL (png_free_ptr)NULL
370
#define png_infopp_NULL (png_infopp)NULL
371
#define png_malloc_ptr_NULL (png_malloc_ptr)NULL
372
#define png_read_status_ptr_NULL (png_read_status_ptr)NULL
373
#define png_rw_ptr_NULL (png_rw_ptr)NULL
374
#define png_structp_NULL (png_structp)NULL
375
#define png_uint_16p_NULL (png_uint_16p)NULL
376
#define png_voidp_NULL (png_voidp)NULL
377
#define png_write_status_ptr_NULL (png_write_status_ptr)NULL
379
#define int_p_NULL NULL
380
#define png_bytep_NULL NULL
381
#define png_bytepp_NULL NULL
382
#define png_doublep_NULL NULL
383
#define png_error_ptr_NULL NULL
384
#define png_flush_ptr_NULL NULL
385
#define png_free_ptr_NULL NULL
386
#define png_infopp_NULL NULL
387
#define png_malloc_ptr_NULL NULL
388
#define png_read_status_ptr_NULL NULL
389
#define png_rw_ptr_NULL NULL
390
#define png_structp_NULL NULL
391
#define png_uint_16p_NULL NULL
392
#define png_voidp_NULL NULL
393
#define png_write_status_ptr_NULL NULL
396
/* variables declared in png.c - only it needs to define PNG_NO_EXTERN */
397
#if !defined(PNG_NO_EXTERN) || defined(PNG_ALWAYS_EXTERN)
398
/* Version information for C files, stored in png.c. This had better match
401
#ifdef PNG_USE_GLOBAL_ARRAYS
402
PNG_EXPORT_VAR (const char) png_libpng_ver[18];
403
/* need room for 99.99.99beta99z */
405
#define png_libpng_ver png_get_header_ver(NULL)
408
#ifdef PNG_USE_GLOBAL_ARRAYS
409
/* This was removed in version 1.0.5c */
410
/* Structures to facilitate easy interlacing. See png.c for more details */
411
PNG_EXPORT_VAR (const int FARDATA) png_pass_start[7];
412
PNG_EXPORT_VAR (const int FARDATA) png_pass_inc[7];
413
PNG_EXPORT_VAR (const int FARDATA) png_pass_ystart[7];
414
PNG_EXPORT_VAR (const int FARDATA) png_pass_yinc[7];
415
PNG_EXPORT_VAR (const int FARDATA) png_pass_mask[7];
416
PNG_EXPORT_VAR (const int FARDATA) png_pass_dsp_mask[7];
417
#ifdef PNG_HAVE_ASSEMBLER_COMBINE_ROW
418
PNG_EXPORT_VAR (const int FARDATA) png_pass_width[7];
420
/* This isn't currently used. If you need it, see png.c for more details.
421
PNG_EXPORT_VAR (const int FARDATA) png_pass_height[7];
425
#endif /* PNG_NO_EXTERN */
427
/* Three color definitions. The order of the red, green, and blue, (and the
428
* exact size) is not important, although the size of the fields need to
429
* be png_byte or png_uint_16 (as defined below).
431
typedef struct png_color_struct
437
typedef png_color FAR * png_colorp;
438
typedef png_color FAR * FAR * png_colorpp;
440
typedef struct png_color_16_struct
442
png_byte index; /* used for palette files */
443
png_uint_16 red; /* for use in red green blue files */
446
png_uint_16 gray; /* for use in grayscale files */
448
typedef png_color_16 FAR * png_color_16p;
449
typedef png_color_16 FAR * FAR * png_color_16pp;
451
typedef struct png_color_8_struct
453
png_byte red; /* for use in red green blue files */
456
png_byte gray; /* for use in grayscale files */
457
png_byte alpha; /* for alpha channel files */
459
typedef png_color_8 FAR * png_color_8p;
460
typedef png_color_8 FAR * FAR * png_color_8pp;
463
* The following two structures are used for the in-core representation
466
typedef struct png_sPLT_entry_struct
472
png_uint_16 frequency;
474
typedef png_sPLT_entry FAR * png_sPLT_entryp;
475
typedef png_sPLT_entry FAR * FAR * png_sPLT_entrypp;
477
/* When the depth of the sPLT palette is 8 bits, the color and alpha samples
478
* occupy the LSB of their respective members, and the MSB of each member
479
* is zero-filled. The frequency member always occupies the full 16 bits.
482
typedef struct png_sPLT_struct
484
png_charp name; /* palette name */
485
png_byte depth; /* depth of palette samples */
486
png_sPLT_entryp entries; /* palette entries */
487
png_int_32 nentries; /* number of palette entries */
489
typedef png_sPLT_t FAR * png_sPLT_tp;
490
typedef png_sPLT_t FAR * FAR * png_sPLT_tpp;
492
#ifdef PNG_TEXT_SUPPORTED
493
/* png_text holds the contents of a text/ztxt/itxt chunk in a PNG file,
494
* and whether that contents is compressed or not. The "key" field
495
* points to a regular zero-terminated C string. The "text", "lang", and
496
* "lang_key" fields can be regular C strings, empty strings, or NULL pointers.
497
* However, the * structure returned by png_get_text() will always contain
498
* regular zero-terminated C strings (possibly empty), never NULL pointers,
499
* so they can be safely used in printf() and other string-handling functions.
501
typedef struct png_text_struct
503
int compression; /* compression value:
508
png_charp key; /* keyword, 1-79 character description of "text" */
509
png_charp text; /* comment, may be an empty string (ie "")
511
png_size_t text_length; /* length of the text string */
512
#ifdef PNG_iTXt_SUPPORTED
513
png_size_t itxt_length; /* length of the itxt string */
514
png_charp lang; /* language code, 0-79 characters
516
png_charp lang_key; /* keyword translated UTF-8 string, 0 or more
517
chars or a NULL pointer */
520
typedef png_text FAR * png_textp;
521
typedef png_text FAR * FAR * png_textpp;
524
/* Supported compression types for text in PNG files (tEXt, and zTXt).
525
* The values of the PNG_TEXT_COMPRESSION_ defines should NOT be changed. */
526
#define PNG_TEXT_COMPRESSION_NONE_WR -3
527
#define PNG_TEXT_COMPRESSION_zTXt_WR -2
528
#define PNG_TEXT_COMPRESSION_NONE -1
529
#define PNG_TEXT_COMPRESSION_zTXt 0
530
#define PNG_ITXT_COMPRESSION_NONE 1
531
#define PNG_ITXT_COMPRESSION_zTXt 2
532
#define PNG_TEXT_COMPRESSION_LAST 3 /* Not a valid value */
534
/* png_time is a way to hold the time in an machine independent way.
535
* Two conversions are provided, both from time_t and struct tm. There
536
* is no portable way to convert to either of these structures, as far
537
* as I know. If you know of a portable way, send it to me. As a side
538
* note - PNG has always been Year 2000 compliant!
540
typedef struct png_time_struct
542
png_uint_16 year; /* full year, as in, 1995 */
543
png_byte month; /* month of year, 1 - 12 */
544
png_byte day; /* day of month, 1 - 31 */
545
png_byte hour; /* hour of day, 0 - 23 */
546
png_byte minute; /* minute of hour, 0 - 59 */
547
png_byte second; /* second of minute, 0 - 60 (for leap seconds) */
549
typedef png_time FAR * png_timep;
550
typedef png_time FAR * FAR * png_timepp;
552
#if defined(PNG_UNKNOWN_CHUNKS_SUPPORTED)
553
/* png_unknown_chunk is a structure to hold queued chunks for which there is
554
* no specific support. The idea is that we can use this to queue
555
* up private chunks for output even though the library doesn't actually
556
* know about their semantics.
558
typedef struct png_unknown_chunk_t
564
/* libpng-using applications should NOT directly modify this byte. */
565
png_byte location; /* mode of operation at read time */
568
typedef png_unknown_chunk FAR * png_unknown_chunkp;
569
typedef png_unknown_chunk FAR * FAR * png_unknown_chunkpp;
572
/* png_info is a structure that holds the information in a PNG file so
573
* that the application can find out the characteristics of the image.
574
* If you are reading the file, this structure will tell you what is
575
* in the PNG file. If you are writing the file, fill in the information
576
* you want to put into the PNG file, then call png_write_info().
577
* The names chosen should be very close to the PNG specification, so
578
* consult that document for information about the meaning of each field.
580
* With libpng < 0.95, it was only possible to directly set and read the
581
* the values in the png_info_struct, which meant that the contents and
582
* order of the values had to remain fixed. With libpng 0.95 and later,
583
* however, there are now functions that abstract the contents of
584
* png_info_struct from the application, so this makes it easier to use
585
* libpng with dynamic libraries, and even makes it possible to use
586
* libraries that don't have all of the libpng ancillary chunk-handing
589
* In any case, the order of the parameters in png_info_struct should NOT
590
* be changed for as long as possible to keep compatibility with applications
591
* that use the old direct-access method with png_info_struct.
593
* The following members may have allocated storage attached that should be
594
* cleaned up before the structure is discarded: palette, trans, text,
595
* pcal_purpose, pcal_units, pcal_params, hist, iccp_name, iccp_profile,
596
* splt_palettes, scal_unit, row_pointers, and unknowns. By default, these
597
* are automatically freed when the info structure is deallocated, if they were
598
* allocated internally by libpng. This behavior can be changed by means
599
* of the png_data_freer() function.
601
* More allocation details: all the chunk-reading functions that
602
* change these members go through the corresponding png_set_*
603
* functions. A function to clear these members is available: see
604
* png_free_data(). The png_set_* functions do not depend on being
605
* able to point info structure members to any of the storage they are
606
* passed (they make their own copies), EXCEPT that the png_set_text
607
* functions use the same storage passed to them in the text_ptr or
608
* itxt_ptr structure argument, and the png_set_rows and png_set_unknowns
609
* functions do not make their own copies.
611
typedef struct png_info_struct
613
/* the following are necessary for every PNG file */
614
png_uint_32 width; /* width of image in pixels (from IHDR) */
615
png_uint_32 height; /* height of image in pixels (from IHDR) */
616
png_uint_32 valid; /* valid chunk data (see PNG_INFO_ below) */
617
png_uint_32 rowbytes; /* bytes needed to hold an untransformed row */
618
png_colorp palette; /* array of color values (valid & PNG_INFO_PLTE) */
619
png_uint_16 num_palette; /* number of color entries in "palette" (PLTE) */
620
png_uint_16 num_trans; /* number of transparent palette color (tRNS) */
621
png_byte bit_depth; /* 1, 2, 4, 8, or 16 bits/channel (from IHDR) */
622
png_byte color_type; /* see PNG_COLOR_TYPE_ below (from IHDR) */
623
/* The following three should have been named *_method not *_type */
624
png_byte compression_type; /* must be PNG_COMPRESSION_TYPE_BASE (IHDR) */
625
png_byte filter_type; /* must be PNG_FILTER_TYPE_BASE (from IHDR) */
626
png_byte interlace_type; /* One of PNG_INTERLACE_NONE, PNG_INTERLACE_ADAM7 */
628
/* The following is informational only on read, and not used on writes. */
629
png_byte channels; /* number of data channels per pixel (1, 2, 3, 4) */
630
png_byte pixel_depth; /* number of bits per pixel */
631
png_byte spare_byte; /* to align the data, and for future use */
632
png_byte signature[8]; /* magic bytes read by libpng from start of file */
634
/* The rest of the data is optional. If you are reading, check the
635
* valid field to see if the information in these are valid. If you
636
* are writing, set the valid field to those chunks you want written,
637
* and initialize the appropriate fields below.
640
#if defined(PNG_gAMA_SUPPORTED) && defined(PNG_FLOATING_POINT_SUPPORTED)
641
/* The gAMA chunk describes the gamma characteristics of the system
642
* on which the image was created, normally in the range [1.0, 2.5].
643
* Data is valid if (valid & PNG_INFO_gAMA) is non-zero.
645
float gamma; /* gamma value of image, if (valid & PNG_INFO_gAMA) */
648
#if defined(PNG_sRGB_SUPPORTED)
650
/* Data valid if (valid & PNG_INFO_sRGB) non-zero. */
651
png_byte srgb_intent; /* sRGB rendering intent [0, 1, 2, or 3] */
654
#if defined(PNG_TEXT_SUPPORTED)
655
/* The tEXt, and zTXt chunks contain human-readable textual data in
656
* uncompressed, compressed, and optionally compressed forms, respectively.
657
* The data in "text" is an array of pointers to uncompressed,
658
* null-terminated C strings. Each chunk has a keyword that describes the
659
* textual data contained in that chunk. Keywords are not required to be
660
* unique, and the text string may be empty. Any number of text chunks may
663
int num_text; /* number of comments read/to write */
664
int max_text; /* current size of text array */
665
png_textp text; /* array of comments read/to write */
666
#endif /* PNG_TEXT_SUPPORTED */
668
#if defined(PNG_tIME_SUPPORTED)
669
/* The tIME chunk holds the last time the displayed image data was
670
* modified. See the png_time struct for the contents of this struct.
675
#if defined(PNG_sBIT_SUPPORTED)
676
/* The sBIT chunk specifies the number of significant high-order bits
677
* in the pixel data. Values are in the range [1, bit_depth], and are
678
* only specified for the channels in the pixel data. The contents of
679
* the low-order bits is not specified. Data is valid if
680
* (valid & PNG_INFO_sBIT) is non-zero.
682
png_color_8 sig_bit; /* significant bits in color channels */
685
#if defined(PNG_tRNS_SUPPORTED) || defined(PNG_READ_EXPAND_SUPPORTED) || \
686
defined(PNG_READ_BACKGROUND_SUPPORTED)
687
/* The tRNS chunk supplies transparency data for paletted images and
688
* other image types that don't need a full alpha channel. There are
689
* "num_trans" transparency values for a paletted image, stored in the
690
* same order as the palette colors, starting from index 0. Values
691
* for the data are in the range [0, 255], ranging from fully transparent
692
* to fully opaque, respectively. For non-paletted images, there is a
693
* single color specified that should be treated as fully transparent.
694
* Data is valid if (valid & PNG_INFO_tRNS) is non-zero.
696
png_bytep trans; /* transparent values for paletted image */
697
png_color_16 trans_values; /* transparent color for non-palette image */
700
#if defined(PNG_bKGD_SUPPORTED) || defined(PNG_READ_BACKGROUND_SUPPORTED)
701
/* The bKGD chunk gives the suggested image background color if the
702
* display program does not have its own background color and the image
703
* is needs to composited onto a background before display. The colors
704
* in "background" are normally in the same color space/depth as the
705
* pixel data. Data is valid if (valid & PNG_INFO_bKGD) is non-zero.
707
png_color_16 background;
710
#if defined(PNG_oFFs_SUPPORTED)
711
/* The oFFs chunk gives the offset in "offset_unit_type" units rightwards
712
* and downwards from the top-left corner of the display, page, or other
713
* application-specific co-ordinate space. See the PNG_OFFSET_ defines
714
* below for the unit types. Valid if (valid & PNG_INFO_oFFs) non-zero.
716
png_int_32 x_offset; /* x offset on page */
717
png_int_32 y_offset; /* y offset on page */
718
png_byte offset_unit_type; /* offset units type */
721
#if defined(PNG_pHYs_SUPPORTED)
722
/* The pHYs chunk gives the physical pixel density of the image for
723
* display or printing in "phys_unit_type" units (see PNG_RESOLUTION_
724
* defines below). Data is valid if (valid & PNG_INFO_pHYs) is non-zero.
726
png_uint_32 x_pixels_per_unit; /* horizontal pixel density */
727
png_uint_32 y_pixels_per_unit; /* vertical pixel density */
728
png_byte phys_unit_type; /* resolution type (see PNG_RESOLUTION_ below) */
731
#if defined(PNG_hIST_SUPPORTED)
732
/* The hIST chunk contains the relative frequency or importance of the
733
* various palette entries, so that a viewer can intelligently select a
734
* reduced-color palette, if required. Data is an array of "num_palette"
735
* values in the range [0,65535]. Data valid if (valid & PNG_INFO_hIST)
741
#ifdef PNG_cHRM_SUPPORTED
742
/* The cHRM chunk describes the CIE color characteristics of the monitor
743
* on which the PNG was created. This data allows the viewer to do gamut
744
* mapping of the input image to ensure that the viewer sees the same
745
* colors in the image as the creator. Values are in the range
746
* [0.0, 0.8]. Data valid if (valid & PNG_INFO_cHRM) non-zero.
748
#ifdef PNG_FLOATING_POINT_SUPPORTED
760
#if defined(PNG_pCAL_SUPPORTED)
761
/* The pCAL chunk describes a transformation between the stored pixel
762
* values and original physical data values used to create the image.
763
* The integer range [0, 2^bit_depth - 1] maps to the floating-point
764
* range given by [pcal_X0, pcal_X1], and are further transformed by a
765
* (possibly non-linear) transformation function given by "pcal_type"
766
* and "pcal_params" into "pcal_units". Please see the PNG_EQUATION_
767
* defines below, and the PNG-Group's PNG extensions document for a
768
* complete description of the transformations and how they should be
769
* implemented, and for a description of the ASCII parameter strings.
770
* Data values are valid if (valid & PNG_INFO_pCAL) non-zero.
772
png_charp pcal_purpose; /* pCAL chunk description string */
773
png_int_32 pcal_X0; /* minimum value */
774
png_int_32 pcal_X1; /* maximum value */
775
png_charp pcal_units; /* Latin-1 string giving physical units */
776
png_charpp pcal_params; /* ASCII strings containing parameter values */
777
png_byte pcal_type; /* equation type (see PNG_EQUATION_ below) */
778
png_byte pcal_nparams; /* number of parameters given in pcal_params */
781
/* New members added in libpng-1.0.6 */
782
#ifdef PNG_FREE_ME_SUPPORTED
783
png_uint_32 free_me; /* flags items libpng is responsible for freeing */
786
#if defined(PNG_UNKNOWN_CHUNKS_SUPPORTED)
787
/* storage for unknown chunks that the library doesn't recognize. */
788
png_unknown_chunkp unknown_chunks;
789
png_size_t unknown_chunks_num;
792
#if defined(PNG_iCCP_SUPPORTED)
793
/* iCCP chunk data. */
794
png_charp iccp_name; /* profile name */
795
png_charp iccp_profile; /* International Color Consortium profile data */
796
/* Note to maintainer: should be png_bytep */
797
png_uint_32 iccp_proflen; /* ICC profile data length */
798
png_byte iccp_compression; /* Always zero */
801
#if defined(PNG_sPLT_SUPPORTED)
802
/* data on sPLT chunks (there may be more than one). */
803
png_sPLT_tp splt_palettes;
804
png_uint_32 splt_palettes_num;
807
#if defined(PNG_sCAL_SUPPORTED)
808
/* The sCAL chunk describes the actual physical dimensions of the
809
* subject matter of the graphic. The chunk contains a unit specification
810
* a byte value, and two ASCII strings representing floating-point
811
* values. The values are width and height corresponsing to one pixel
812
* in the image. This external representation is converted to double
813
* here. Data values are valid if (valid & PNG_INFO_sCAL) is non-zero.
815
png_byte scal_unit; /* unit of physical scale */
816
#ifdef PNG_FLOATING_POINT_SUPPORTED
817
double scal_pixel_width; /* width of one pixel */
818
double scal_pixel_height; /* height of one pixel */
820
#ifdef PNG_FIXED_POINT_SUPPORTED
821
png_charp scal_s_width; /* string containing height */
822
png_charp scal_s_height; /* string containing width */
826
#if defined(PNG_INFO_IMAGE_SUPPORTED)
827
/* Memory has been allocated if (valid & PNG_ALLOCATED_INFO_ROWS) non-zero */
828
/* Data valid if (valid & PNG_INFO_IDAT) non-zero */
829
png_bytepp row_pointers; /* the image bits */
832
#if defined(PNG_FIXED_POINT_SUPPORTED) && defined(PNG_gAMA_SUPPORTED)
833
png_fixed_point int_gamma; /* gamma of image, if (valid & PNG_INFO_gAMA) */
836
#if defined(PNG_cHRM_SUPPORTED) && defined(PNG_FIXED_POINT_SUPPORTED)
837
png_fixed_point int_x_white;
838
png_fixed_point int_y_white;
839
png_fixed_point int_x_red;
840
png_fixed_point int_y_red;
841
png_fixed_point int_x_green;
842
png_fixed_point int_y_green;
843
png_fixed_point int_x_blue;
844
png_fixed_point int_y_blue;
849
typedef png_info FAR * png_infop;
850
typedef png_info FAR * FAR * png_infopp;
852
/* Maximum positive integer used in PNG is (2^31)-1 */
853
#define PNG_UINT_31_MAX ((png_uint_32)0x7fffffffL)
854
#define PNG_UINT_32_MAX (~((png_uint_32)0))
855
#define PNG_SIZE_MAX (~((png_size_t)0))
856
/* PNG_MAX_UINT is deprecated; use PNG_UINT_31_MAX instead. */
857
#define PNG_MAX_UINT PNG_UINT_31_MAX
859
/* These describe the color_type field in png_info. */
860
/* color type masks */
861
#define PNG_COLOR_MASK_PALETTE 1
862
#define PNG_COLOR_MASK_COLOR 2
863
#define PNG_COLOR_MASK_ALPHA 4
865
/* color types. Note that not all combinations are legal */
866
#define PNG_COLOR_TYPE_GRAY 0
867
#define PNG_COLOR_TYPE_PALETTE (PNG_COLOR_MASK_COLOR | PNG_COLOR_MASK_PALETTE)
868
#define PNG_COLOR_TYPE_RGB (PNG_COLOR_MASK_COLOR)
869
#define PNG_COLOR_TYPE_RGB_ALPHA (PNG_COLOR_MASK_COLOR | PNG_COLOR_MASK_ALPHA)
870
#define PNG_COLOR_TYPE_GRAY_ALPHA (PNG_COLOR_MASK_ALPHA)
872
#define PNG_COLOR_TYPE_RGBA PNG_COLOR_TYPE_RGB_ALPHA
873
#define PNG_COLOR_TYPE_GA PNG_COLOR_TYPE_GRAY_ALPHA
875
/* This is for compression type. PNG 1.0-1.2 only define the single type. */
876
#define PNG_COMPRESSION_TYPE_BASE 0 /* Deflate method 8, 32K window */
877
#define PNG_COMPRESSION_TYPE_DEFAULT PNG_COMPRESSION_TYPE_BASE
879
/* This is for filter type. PNG 1.0-1.2 only define the single type. */
880
#define PNG_FILTER_TYPE_BASE 0 /* Single row per-byte filtering */
881
#define PNG_INTRAPIXEL_DIFFERENCING 64 /* Used only in MNG datastreams */
882
#define PNG_FILTER_TYPE_DEFAULT PNG_FILTER_TYPE_BASE
884
/* These are for the interlacing type. These values should NOT be changed. */
885
#define PNG_INTERLACE_NONE 0 /* Non-interlaced image */
886
#define PNG_INTERLACE_ADAM7 1 /* Adam7 interlacing */
887
#define PNG_INTERLACE_LAST 2 /* Not a valid value */
889
/* These are for the oFFs chunk. These values should NOT be changed. */
890
#define PNG_OFFSET_PIXEL 0 /* Offset in pixels */
891
#define PNG_OFFSET_MICROMETER 1 /* Offset in micrometers (1/10^6 meter) */
892
#define PNG_OFFSET_LAST 2 /* Not a valid value */
894
/* These are for the pCAL chunk. These values should NOT be changed. */
895
#define PNG_EQUATION_LINEAR 0 /* Linear transformation */
896
#define PNG_EQUATION_BASE_E 1 /* Exponential base e transform */
897
#define PNG_EQUATION_ARBITRARY 2 /* Arbitrary base exponential transform */
898
#define PNG_EQUATION_HYPERBOLIC 3 /* Hyperbolic sine transformation */
899
#define PNG_EQUATION_LAST 4 /* Not a valid value */
901
/* These are for the sCAL chunk. These values should NOT be changed. */
902
#define PNG_SCALE_UNKNOWN 0 /* unknown unit (image scale) */
903
#define PNG_SCALE_METER 1 /* meters per pixel */
904
#define PNG_SCALE_RADIAN 2 /* radians per pixel */
905
#define PNG_SCALE_LAST 3 /* Not a valid value */
907
/* These are for the pHYs chunk. These values should NOT be changed. */
908
#define PNG_RESOLUTION_UNKNOWN 0 /* pixels/unknown unit (aspect ratio) */
909
#define PNG_RESOLUTION_METER 1 /* pixels/meter */
910
#define PNG_RESOLUTION_LAST 2 /* Not a valid value */
912
/* These are for the sRGB chunk. These values should NOT be changed. */
913
#define PNG_sRGB_INTENT_PERCEPTUAL 0
914
#define PNG_sRGB_INTENT_RELATIVE 1
915
#define PNG_sRGB_INTENT_SATURATION 2
916
#define PNG_sRGB_INTENT_ABSOLUTE 3
917
#define PNG_sRGB_INTENT_LAST 4 /* Not a valid value */
919
/* This is for text chunks */
920
#define PNG_KEYWORD_MAX_LENGTH 79
922
/* Maximum number of entries in PLTE/sPLT/tRNS arrays */
923
#define PNG_MAX_PALETTE_LENGTH 256
925
/* These determine if an ancillary chunk's data has been successfully read
926
* from the PNG header, or if the application has filled in the corresponding
927
* data in the info_struct to be written into the output file. The values
928
* of the PNG_INFO_<chunk> defines should NOT be changed.
930
#define PNG_INFO_gAMA 0x0001
931
#define PNG_INFO_sBIT 0x0002
932
#define PNG_INFO_cHRM 0x0004
933
#define PNG_INFO_PLTE 0x0008
934
#define PNG_INFO_tRNS 0x0010
935
#define PNG_INFO_bKGD 0x0020
936
#define PNG_INFO_hIST 0x0040
937
#define PNG_INFO_pHYs 0x0080
938
#define PNG_INFO_oFFs 0x0100
939
#define PNG_INFO_tIME 0x0200
940
#define PNG_INFO_pCAL 0x0400
941
#define PNG_INFO_sRGB 0x0800 /* GR-P, 0.96a */
942
#define PNG_INFO_iCCP 0x1000 /* ESR, 1.0.6 */
943
#define PNG_INFO_sPLT 0x2000 /* ESR, 1.0.6 */
944
#define PNG_INFO_sCAL 0x4000 /* ESR, 1.0.6 */
945
#define PNG_INFO_IDAT 0x8000L /* ESR, 1.0.6 */
947
/* This is used for the transformation routines, as some of them
948
* change these values for the row. It also should enable using
949
* the routines for other purposes.
951
typedef struct png_row_info_struct
953
png_uint_32 width; /* width of row */
954
png_uint_32 rowbytes; /* number of bytes in row */
955
png_byte color_type; /* color type of row */
956
png_byte bit_depth; /* bit depth of row */
957
png_byte channels; /* number of channels (1, 2, 3, or 4) */
958
png_byte pixel_depth; /* bits per pixel (depth * channels) */
961
typedef png_row_info FAR * png_row_infop;
962
typedef png_row_info FAR * FAR * png_row_infopp;
964
/* These are the function types for the I/O functions and for the functions
965
* that allow the user to override the default I/O functions with his or her
966
* own. The png_error_ptr type should match that of user-supplied warning
967
* and error functions, while the png_rw_ptr type should match that of the
968
* user read/write data functions.
970
typedef struct png_struct_def png_struct;
971
typedef png_struct FAR * png_structp;
973
typedef void (PNGAPI *png_error_ptr) PNGARG((png_structp, png_const_charp));
974
typedef void (PNGAPI *png_rw_ptr) PNGARG((png_structp, png_bytep, png_size_t));
975
typedef void (PNGAPI *png_flush_ptr) PNGARG((png_structp));
976
typedef void (PNGAPI *png_read_status_ptr) PNGARG((png_structp, png_uint_32,
978
typedef void (PNGAPI *png_write_status_ptr) PNGARG((png_structp, png_uint_32,
981
#ifdef PNG_PROGRESSIVE_READ_SUPPORTED
982
typedef void (PNGAPI *png_progressive_info_ptr) PNGARG((png_structp, png_infop));
983
typedef void (PNGAPI *png_progressive_end_ptr) PNGARG((png_structp, png_infop));
984
typedef void (PNGAPI *png_progressive_row_ptr) PNGARG((png_structp, png_bytep,
988
#if defined(PNG_READ_USER_TRANSFORM_SUPPORTED) || \
989
defined(PNG_WRITE_USER_TRANSFORM_SUPPORTED) || \
990
defined(PNG_LEGACY_SUPPORTED)
991
typedef void (PNGAPI *png_user_transform_ptr) PNGARG((png_structp,
992
png_row_infop, png_bytep));
995
#if defined(PNG_USER_CHUNKS_SUPPORTED)
996
typedef int (PNGAPI *png_user_chunk_ptr) PNGARG((png_structp, png_unknown_chunkp));
998
#if defined(PNG_UNKNOWN_CHUNKS_SUPPORTED)
999
typedef void (PNGAPI *png_unknown_chunk_ptr) PNGARG((png_structp));
1002
/* Transform masks for the high-level interface */
1003
#define PNG_TRANSFORM_IDENTITY 0x0000 /* read and write */
1004
#define PNG_TRANSFORM_STRIP_16 0x0001 /* read only */
1005
#define PNG_TRANSFORM_STRIP_ALPHA 0x0002 /* read only */
1006
#define PNG_TRANSFORM_PACKING 0x0004 /* read and write */
1007
#define PNG_TRANSFORM_PACKSWAP 0x0008 /* read and write */
1008
#define PNG_TRANSFORM_EXPAND 0x0010 /* read only */
1009
#define PNG_TRANSFORM_INVERT_MONO 0x0020 /* read and write */
1010
#define PNG_TRANSFORM_SHIFT 0x0040 /* read and write */
1011
#define PNG_TRANSFORM_BGR 0x0080 /* read and write */
1012
#define PNG_TRANSFORM_SWAP_ALPHA 0x0100 /* read and write */
1013
#define PNG_TRANSFORM_SWAP_ENDIAN 0x0200 /* read and write */
1014
#define PNG_TRANSFORM_INVERT_ALPHA 0x0400 /* read and write */
1015
#define PNG_TRANSFORM_STRIP_FILLER 0x0800 /* WRITE only */
1017
/* Flags for MNG supported features */
1018
#define PNG_FLAG_MNG_EMPTY_PLTE 0x01
1019
#define PNG_FLAG_MNG_FILTER_64 0x04
1020
#define PNG_ALL_MNG_FEATURES 0x05
1022
typedef png_voidp (*png_malloc_ptr) PNGARG((png_structp, png_size_t));
1023
typedef void (*png_free_ptr) PNGARG((png_structp, png_voidp));
1025
/* The structure that holds the information to read and write PNG files.
1026
* The only people who need to care about what is inside of this are the
1027
* people who will be modifying the library for their own special needs.
1028
* It should NOT be accessed directly by an application, except to store
1032
struct png_struct_def
1034
#ifdef PNG_SETJMP_SUPPORTED
1035
jmp_buf jmpbuf; /* used in png_error */
1037
png_error_ptr error_fn; /* function for printing errors and aborting */
1038
png_error_ptr warning_fn; /* function for printing warnings */
1039
png_voidp error_ptr; /* user supplied struct for error functions */
1040
png_rw_ptr write_data_fn; /* function for writing output data */
1041
png_rw_ptr read_data_fn; /* function for reading input data */
1042
png_voidp io_ptr; /* ptr to application struct for I/O functions */
1044
#if defined(PNG_READ_USER_TRANSFORM_SUPPORTED)
1045
png_user_transform_ptr read_user_transform_fn; /* user read transform */
1048
#if defined(PNG_WRITE_USER_TRANSFORM_SUPPORTED)
1049
png_user_transform_ptr write_user_transform_fn; /* user write transform */
1052
/* These were added in libpng-1.0.2 */
1053
#if defined(PNG_USER_TRANSFORM_PTR_SUPPORTED)
1054
#if defined(PNG_READ_USER_TRANSFORM_SUPPORTED) || \
1055
defined(PNG_WRITE_USER_TRANSFORM_SUPPORTED)
1056
png_voidp user_transform_ptr; /* user supplied struct for user transform */
1057
png_byte user_transform_depth; /* bit depth of user transformed pixels */
1058
png_byte user_transform_channels; /* channels in user transformed pixels */
1062
png_uint_32 mode; /* tells us where we are in the PNG file */
1063
png_uint_32 flags; /* flags indicating various things to libpng */
1064
png_uint_32 transformations; /* which transformations to perform */
1066
z_stream zstream; /* pointer to decompression structure (below) */
1067
png_bytep zbuf; /* buffer for zlib */
1068
png_size_t zbuf_size; /* size of zbuf */
1069
int zlib_level; /* holds zlib compression level */
1070
int zlib_method; /* holds zlib compression method */
1071
int zlib_window_bits; /* holds zlib compression window bits */
1072
int zlib_mem_level; /* holds zlib compression memory level */
1073
int zlib_strategy; /* holds zlib compression strategy */
1075
png_uint_32 width; /* width of image in pixels */
1076
png_uint_32 height; /* height of image in pixels */
1077
png_uint_32 num_rows; /* number of rows in current pass */
1078
png_uint_32 usr_width; /* width of row at start of write */
1079
png_uint_32 rowbytes; /* size of row in bytes */
1080
png_uint_32 irowbytes; /* size of current interlaced row in bytes */
1081
png_uint_32 iwidth; /* width of current interlaced row in pixels */
1082
png_uint_32 row_number; /* current row in interlace pass */
1083
png_bytep prev_row; /* buffer to save previous (unfiltered) row */
1084
png_bytep row_buf; /* buffer to save current (unfiltered) row */
1085
png_bytep sub_row; /* buffer to save "sub" row when filtering */
1086
png_bytep up_row; /* buffer to save "up" row when filtering */
1087
png_bytep avg_row; /* buffer to save "avg" row when filtering */
1088
png_bytep paeth_row; /* buffer to save "Paeth" row when filtering */
1089
png_row_info row_info; /* used for transformation routines */
1091
png_uint_32 idat_size; /* current IDAT size for read */
1092
png_uint_32 crc; /* current chunk CRC value */
1093
png_colorp palette; /* palette from the input file */
1094
png_uint_16 num_palette; /* number of color entries in palette */
1095
png_uint_16 num_trans; /* number of transparency values */
1096
png_byte chunk_name[5]; /* null-terminated name of current chunk */
1097
png_byte compression; /* file compression type (always 0) */
1098
png_byte filter; /* file filter type (always 0) */
1099
png_byte interlaced; /* PNG_INTERLACE_NONE, PNG_INTERLACE_ADAM7 */
1100
png_byte pass; /* current interlace pass (0 - 6) */
1101
png_byte do_filter; /* row filter flags (see PNG_FILTER_ below ) */
1102
png_byte color_type; /* color type of file */
1103
png_byte bit_depth; /* bit depth of file */
1104
png_byte usr_bit_depth; /* bit depth of users row */
1105
png_byte pixel_depth; /* number of bits per pixel */
1106
png_byte channels; /* number of channels in file */
1107
png_byte usr_channels; /* channels at start of write */
1108
png_byte sig_bytes; /* magic bytes read/written from start of file */
1110
#if defined(PNG_READ_FILLER_SUPPORTED) || defined(PNG_WRITE_FILLER_SUPPORTED)
1111
#ifdef PNG_LEGACY_SUPPORTED
1112
png_byte filler; /* filler byte for pixel expansion */
1114
png_uint_16 filler; /* filler bytes for pixel expansion */
1118
#if defined(PNG_bKGD_SUPPORTED)
1119
png_byte background_gamma_type;
1120
# ifdef PNG_FLOATING_POINT_SUPPORTED
1121
float background_gamma;
1123
png_color_16 background; /* background color in screen gamma space */
1124
#if defined(PNG_READ_GAMMA_SUPPORTED)
1125
png_color_16 background_1; /* background normalized to gamma 1.0 */
1127
#endif /* PNG_bKGD_SUPPORTED */
1129
#if defined(PNG_WRITE_FLUSH_SUPPORTED)
1130
png_flush_ptr output_flush_fn;/* Function for flushing output */
1131
png_uint_32 flush_dist; /* how many rows apart to flush, 0 - no flush */
1132
png_uint_32 flush_rows; /* number of rows written since last flush */
1135
#if defined(PNG_READ_GAMMA_SUPPORTED) || defined(PNG_READ_BACKGROUND_SUPPORTED)
1136
int gamma_shift; /* number of "insignificant" bits 16-bit gamma */
1137
#ifdef PNG_FLOATING_POINT_SUPPORTED
1138
float gamma; /* file gamma value */
1139
float screen_gamma; /* screen gamma value (display_exponent) */
1143
#if defined(PNG_READ_GAMMA_SUPPORTED) || defined(PNG_READ_BACKGROUND_SUPPORTED)
1144
png_bytep gamma_table; /* gamma table for 8-bit depth files */
1145
png_bytep gamma_from_1; /* converts from 1.0 to screen */
1146
png_bytep gamma_to_1; /* converts from file to 1.0 */
1147
png_uint_16pp gamma_16_table; /* gamma table for 16-bit depth files */
1148
png_uint_16pp gamma_16_from_1; /* converts from 1.0 to screen */
1149
png_uint_16pp gamma_16_to_1; /* converts from file to 1.0 */
1152
#if defined(PNG_READ_GAMMA_SUPPORTED) || defined(PNG_sBIT_SUPPORTED)
1153
png_color_8 sig_bit; /* significant bits in each available channel */
1156
#if defined(PNG_READ_SHIFT_SUPPORTED) || defined(PNG_WRITE_SHIFT_SUPPORTED)
1157
png_color_8 shift; /* shift for significant bit tranformation */
1160
#if defined(PNG_tRNS_SUPPORTED) || defined(PNG_READ_BACKGROUND_SUPPORTED) \
1161
|| defined(PNG_READ_EXPAND_SUPPORTED) || defined(PNG_READ_BACKGROUND_SUPPORTED)
1162
png_bytep trans; /* transparency values for paletted files */
1163
png_color_16 trans_values; /* transparency values for non-paletted files */
1166
png_read_status_ptr read_row_fn; /* called after each row is decoded */
1167
png_write_status_ptr write_row_fn; /* called after each row is encoded */
1168
#ifdef PNG_PROGRESSIVE_READ_SUPPORTED
1169
png_progressive_info_ptr info_fn; /* called after header data fully read */
1170
png_progressive_row_ptr row_fn; /* called after each prog. row is decoded */
1171
png_progressive_end_ptr end_fn; /* called after image is complete */
1172
png_bytep save_buffer_ptr; /* current location in save_buffer */
1173
png_bytep save_buffer; /* buffer for previously read data */
1174
png_bytep current_buffer_ptr; /* current location in current_buffer */
1175
png_bytep current_buffer; /* buffer for recently used data */
1176
png_uint_32 push_length; /* size of current input chunk */
1177
png_uint_32 skip_length; /* bytes to skip in input data */
1178
png_size_t save_buffer_size; /* amount of data now in save_buffer */
1179
png_size_t save_buffer_max; /* total size of save_buffer */
1180
png_size_t buffer_size; /* total amount of available input data */
1181
png_size_t current_buffer_size; /* amount of data now in current_buffer */
1182
int process_mode; /* what push library is currently doing */
1183
int cur_palette; /* current push library palette index */
1185
# if defined(PNG_TEXT_SUPPORTED)
1186
png_size_t current_text_size; /* current size of text input data */
1187
png_size_t current_text_left; /* how much text left to read in input */
1188
png_charp current_text; /* current text chunk buffer */
1189
png_charp current_text_ptr; /* current location in current_text */
1190
# endif /* PNG_PROGRESSIVE_READ_SUPPORTED && PNG_TEXT_SUPPORTED */
1192
#endif /* PNG_PROGRESSIVE_READ_SUPPORTED */
1194
#if defined(__TURBOC__) && !defined(_Windows) && !defined(__FLAT__)
1195
/* for the Borland special 64K segment handler */
1196
png_bytepp offset_table_ptr;
1197
png_bytep offset_table;
1198
png_uint_16 offset_table_number;
1199
png_uint_16 offset_table_count;
1200
png_uint_16 offset_table_count_free;
1203
#if defined(PNG_READ_DITHER_SUPPORTED)
1204
png_bytep palette_lookup; /* lookup table for dithering */
1205
png_bytep dither_index; /* index translation for palette files */
1208
#if defined(PNG_READ_DITHER_SUPPORTED) || defined(PNG_hIST_SUPPORTED)
1209
png_uint_16p hist; /* histogram */
1212
#if defined(PNG_WRITE_WEIGHTED_FILTER_SUPPORTED)
1213
png_byte heuristic_method; /* heuristic for row filter selection */
1214
png_byte num_prev_filters; /* number of weights for previous rows */
1215
png_bytep prev_filters; /* filter type(s) of previous row(s) */
1216
png_uint_16p filter_weights; /* weight(s) for previous line(s) */
1217
png_uint_16p inv_filter_weights; /* 1/weight(s) for previous line(s) */
1218
png_uint_16p filter_costs; /* relative filter calculation cost */
1219
png_uint_16p inv_filter_costs; /* 1/relative filter calculation cost */
1222
#if defined(PNG_TIME_RFC1123_SUPPORTED)
1223
png_charp time_buffer; /* String to hold RFC 1123 time text */
1226
/* New members added in libpng-1.0.6 */
1228
#ifdef PNG_FREE_ME_SUPPORTED
1229
png_uint_32 free_me; /* flags items libpng is responsible for freeing */
1232
#if defined(PNG_USER_CHUNKS_SUPPORTED)
1233
png_voidp user_chunk_ptr;
1234
png_user_chunk_ptr read_user_chunk_fn; /* user read chunk handler */
1237
#if defined(PNG_UNKNOWN_CHUNKS_SUPPORTED)
1239
png_bytep chunk_list;
1242
/* New members added in libpng-1.0.3 */
1243
#if defined(PNG_READ_RGB_TO_GRAY_SUPPORTED)
1244
png_byte rgb_to_gray_status;
1245
/* These were changed from png_byte in libpng-1.0.6 */
1246
png_uint_16 rgb_to_gray_red_coeff;
1247
png_uint_16 rgb_to_gray_green_coeff;
1248
png_uint_16 rgb_to_gray_blue_coeff;
1251
/* New member added in libpng-1.0.4 (renamed in 1.0.9) */
1252
#if defined(PNG_MNG_FEATURES_SUPPORTED) || \
1253
defined(PNG_READ_EMPTY_PLTE_SUPPORTED) || \
1254
defined(PNG_WRITE_EMPTY_PLTE_SUPPORTED)
1255
/* changed from png_byte to png_uint_32 at version 1.2.0 */
1257
png_byte mng_features_permitted;
1259
png_uint_32 mng_features_permitted;
1260
#endif /* PNG_1_0_X */
1263
/* New member added in libpng-1.0.7 */
1264
#if defined(PNG_READ_GAMMA_SUPPORTED) || defined(PNG_READ_BACKGROUND_SUPPORTED)
1265
png_fixed_point int_gamma;
1268
/* New member added in libpng-1.0.9, ifdef'ed out in 1.0.12, enabled in 1.2.0 */
1269
#if defined(PNG_MNG_FEATURES_SUPPORTED)
1270
png_byte filter_type;
1273
#if defined(PNG_1_0_X) || (defined(PNG_DEBUG) && defined(PNG_USE_PNGGCCRD))
1274
/* New member added in libpng-1.0.10, ifdef'ed out in 1.2.0 */
1275
png_uint_32 row_buf_size;
1278
/* New members added in libpng-1.2.0 */
1279
#if !defined(PNG_1_0_X) && defined(PNG_ASSEMBLER_CODE_SUPPORTED)
1280
png_byte mmx_bitdepth_threshold;
1281
png_uint_32 mmx_rowbytes_threshold;
1282
png_uint_32 asm_flags;
1285
/* New members added in libpng-1.0.2 but first enabled by default in 1.2.0 */
1286
#ifdef PNG_USER_MEM_SUPPORTED
1287
png_voidp mem_ptr; /* user supplied struct for mem functions */
1288
png_malloc_ptr malloc_fn; /* function for allocating memory */
1289
png_free_ptr free_fn; /* function for freeing memory */
1292
/* New member added in libpng-1.0.13 and 1.2.0 */
1293
png_bytep big_row_buf; /* buffer to save current (unfiltered) row */
1295
#if defined(PNG_READ_DITHER_SUPPORTED)
1296
/* The following three members were added at version 1.0.14 and 1.2.4 */
1297
png_bytep dither_sort; /* working sort array */
1298
png_bytep index_to_palette; /* where the original index currently is */
1299
/* in the palette */
1300
png_bytep palette_to_index; /* which original index points to this */
1304
/* New members added in libpng-1.0.16 and 1.2.6 */
1305
png_byte compression_type;
1307
#ifdef PNG_SET_USER_LIMITS_SUPPORTED
1308
png_uint_32 user_width_max;
1309
png_uint_32 user_height_max;
1315
/* This triggers a compiler error in png.c, if png.c and png.h
1316
* do not agree upon the version number.
1318
typedef png_structp version_1_2_7;
1320
typedef png_struct FAR * FAR * png_structpp;
1322
/* Here are the function definitions most commonly used. This is not
1323
* the place to find out how to use libpng. See libpng.txt for the
1324
* full explanation, see example.c for the summary. This just provides
1325
* a simple one line description of the use of each function.
1328
/* Returns the version number of the library */
1329
extern PNG_EXPORT(png_uint_32,png_access_version_number) PNGARG((void));
1331
/* Tell lib we have already handled the first <num_bytes> magic bytes.
1332
* Handling more than 8 bytes from the beginning of the file is an error.
1334
extern PNG_EXPORT(void,png_set_sig_bytes) PNGARG((png_structp png_ptr,
1337
/* Check sig[start] through sig[start + num_to_check - 1] to see if it's a
1338
* PNG file. Returns zero if the supplied bytes match the 8-byte PNG
1339
* signature, and non-zero otherwise. Having num_to_check == 0 or
1340
* start > 7 will always fail (ie return non-zero).
1342
extern PNG_EXPORT(int,png_sig_cmp) PNGARG((png_bytep sig, png_size_t start,
1343
png_size_t num_to_check));
1345
/* Simple signature checking function. This is the same as calling
1346
* png_check_sig(sig, n) := !png_sig_cmp(sig, 0, n).
1348
extern PNG_EXPORT(int,png_check_sig) PNGARG((png_bytep sig, int num));
1350
/* Allocate and initialize png_ptr struct for reading, and any other memory. */
1351
extern PNG_EXPORT(png_structp,png_create_read_struct)
1352
PNGARG((png_const_charp user_png_ver, png_voidp error_ptr,
1353
png_error_ptr error_fn, png_error_ptr warn_fn));
1355
/* Allocate and initialize png_ptr struct for writing, and any other memory */
1356
extern PNG_EXPORT(png_structp,png_create_write_struct)
1357
PNGARG((png_const_charp user_png_ver, png_voidp error_ptr,
1358
png_error_ptr error_fn, png_error_ptr warn_fn));
1360
#ifdef PNG_WRITE_SUPPORTED
1361
extern PNG_EXPORT(png_uint_32,png_get_compression_buffer_size)
1362
PNGARG((png_structp png_ptr));
1365
#ifdef PNG_WRITE_SUPPORTED
1366
extern PNG_EXPORT(void,png_set_compression_buffer_size)
1367
PNGARG((png_structp png_ptr, png_uint_32 size));
1370
/* Reset the compression stream */
1371
extern PNG_EXPORT(int,png_reset_zstream) PNGARG((png_structp png_ptr));
1373
/* New functions added in libpng-1.0.2 (not enabled by default until 1.2.0) */
1374
#ifdef PNG_USER_MEM_SUPPORTED
1375
extern PNG_EXPORT(png_structp,png_create_read_struct_2)
1376
PNGARG((png_const_charp user_png_ver, png_voidp error_ptr,
1377
png_error_ptr error_fn, png_error_ptr warn_fn, png_voidp mem_ptr,
1378
png_malloc_ptr malloc_fn, png_free_ptr free_fn));
1379
extern PNG_EXPORT(png_structp,png_create_write_struct_2)
1380
PNGARG((png_const_charp user_png_ver, png_voidp error_ptr,
1381
png_error_ptr error_fn, png_error_ptr warn_fn, png_voidp mem_ptr,
1382
png_malloc_ptr malloc_fn, png_free_ptr free_fn));
1385
/* Write a PNG chunk - size, type, (optional) data, CRC. */
1386
extern PNG_EXPORT(void,png_write_chunk) PNGARG((png_structp png_ptr,
1387
png_bytep chunk_name, png_bytep data, png_size_t length));
1389
/* Write the start of a PNG chunk - length and chunk name. */
1390
extern PNG_EXPORT(void,png_write_chunk_start) PNGARG((png_structp png_ptr,
1391
png_bytep chunk_name, png_uint_32 length));
1393
/* Write the data of a PNG chunk started with png_write_chunk_start(). */
1394
extern PNG_EXPORT(void,png_write_chunk_data) PNGARG((png_structp png_ptr,
1395
png_bytep data, png_size_t length));
1397
/* Finish a chunk started with png_write_chunk_start() (includes CRC). */
1398
extern PNG_EXPORT(void,png_write_chunk_end) PNGARG((png_structp png_ptr));
1400
/* Allocate and initialize the info structure */
1401
extern PNG_EXPORT(png_infop,png_create_info_struct)
1402
PNGARG((png_structp png_ptr));
1404
/* Initialize the info structure (old interface - DEPRECATED) */
1405
extern PNG_EXPORT(void,png_info_init) PNGARG((png_infop info_ptr));
1406
#undef png_info_init
1407
#define png_info_init(info_ptr) png_info_init_3(&info_ptr,\
1408
png_sizeof(png_info));
1409
extern PNG_EXPORT(void,png_info_init_3) PNGARG((png_infopp info_ptr,
1410
png_size_t png_info_struct_size));
1412
/* Writes all the PNG information before the image. */
1413
extern PNG_EXPORT(void,png_write_info_before_PLTE) PNGARG((png_structp png_ptr,
1414
png_infop info_ptr));
1415
extern PNG_EXPORT(void,png_write_info) PNGARG((png_structp png_ptr,
1416
png_infop info_ptr));
1418
#ifndef PNG_NO_SEQUENTIAL_READ_SUPPORTED
1419
/* read the information before the actual image data. */
1420
extern PNG_EXPORT(void,png_read_info) PNGARG((png_structp png_ptr,
1421
png_infop info_ptr));
1424
#if defined(PNG_TIME_RFC1123_SUPPORTED)
1425
extern PNG_EXPORT(png_charp,png_convert_to_rfc1123)
1426
PNGARG((png_structp png_ptr, png_timep ptime));
1429
#if !defined(_WIN32_WCE)
1430
/* "time.h" functions are not supported on WindowsCE */
1431
#if defined(PNG_WRITE_tIME_SUPPORTED)
1432
/* convert from a struct tm to png_time */
1433
extern PNG_EXPORT(void,png_convert_from_struct_tm) PNGARG((png_timep ptime,
1434
struct tm FAR * ttime));
1436
/* convert from time_t to png_time. Uses gmtime() */
1437
extern PNG_EXPORT(void,png_convert_from_time_t) PNGARG((png_timep ptime,
1439
#endif /* PNG_WRITE_tIME_SUPPORTED */
1440
#endif /* _WIN32_WCE */
1442
#if defined(PNG_READ_EXPAND_SUPPORTED)
1443
/* Expand data to 24-bit RGB, or 8-bit grayscale, with alpha if available. */
1444
extern PNG_EXPORT(void,png_set_expand) PNGARG((png_structp png_ptr));
1445
extern PNG_EXPORT(void,png_set_gray_1_2_4_to_8) PNGARG((png_structp png_ptr));
1446
extern PNG_EXPORT(void,png_set_palette_to_rgb) PNGARG((png_structp png_ptr));
1447
extern PNG_EXPORT(void,png_set_tRNS_to_alpha) PNGARG((png_structp png_ptr));
1450
#if defined(PNG_READ_BGR_SUPPORTED) || defined(PNG_WRITE_BGR_SUPPORTED)
1451
/* Use blue, green, red order for pixels. */
1452
extern PNG_EXPORT(void,png_set_bgr) PNGARG((png_structp png_ptr));
1455
#if defined(PNG_READ_GRAY_TO_RGB_SUPPORTED)
1456
/* Expand the grayscale to 24-bit RGB if necessary. */
1457
extern PNG_EXPORT(void,png_set_gray_to_rgb) PNGARG((png_structp png_ptr));
1460
#if defined(PNG_READ_RGB_TO_GRAY_SUPPORTED)
1461
/* Reduce RGB to grayscale. */
1462
#ifdef PNG_FLOATING_POINT_SUPPORTED
1463
extern PNG_EXPORT(void,png_set_rgb_to_gray) PNGARG((png_structp png_ptr,
1464
int error_action, double red, double green ));
1466
extern PNG_EXPORT(void,png_set_rgb_to_gray_fixed) PNGARG((png_structp png_ptr,
1467
int error_action, png_fixed_point red, png_fixed_point green ));
1468
extern PNG_EXPORT(png_byte,png_get_rgb_to_gray_status) PNGARG((png_structp
1472
extern PNG_EXPORT(void,png_build_grayscale_palette) PNGARG((int bit_depth,
1473
png_colorp palette));
1475
#if defined(PNG_READ_STRIP_ALPHA_SUPPORTED)
1476
extern PNG_EXPORT(void,png_set_strip_alpha) PNGARG((png_structp png_ptr));
1479
#if defined(PNG_READ_SWAP_ALPHA_SUPPORTED) || \
1480
defined(PNG_WRITE_SWAP_ALPHA_SUPPORTED)
1481
extern PNG_EXPORT(void,png_set_swap_alpha) PNGARG((png_structp png_ptr));
1484
#if defined(PNG_READ_INVERT_ALPHA_SUPPORTED) || \
1485
defined(PNG_WRITE_INVERT_ALPHA_SUPPORTED)
1486
extern PNG_EXPORT(void,png_set_invert_alpha) PNGARG((png_structp png_ptr));
1489
#if defined(PNG_READ_FILLER_SUPPORTED) || defined(PNG_WRITE_FILLER_SUPPORTED)
1490
/* Add a filler byte to 8-bit Gray or 24-bit RGB images. */
1491
extern PNG_EXPORT(void,png_set_filler) PNGARG((png_structp png_ptr,
1492
png_uint_32 filler, int flags));
1493
/* The values of the PNG_FILLER_ defines should NOT be changed */
1494
#define PNG_FILLER_BEFORE 0
1495
#define PNG_FILLER_AFTER 1
1496
/* Add an alpha byte to 8-bit Gray or 24-bit RGB images. */
1497
#if !defined(PNG_1_0_X)
1498
extern PNG_EXPORT(void,png_set_add_alpha) PNGARG((png_structp png_ptr,
1499
png_uint_32 filler, int flags));
1501
#endif /* PNG_READ_FILLER_SUPPORTED || PNG_WRITE_FILLER_SUPPORTED */
1503
#if defined(PNG_READ_SWAP_SUPPORTED) || defined(PNG_WRITE_SWAP_SUPPORTED)
1504
/* Swap bytes in 16-bit depth files. */
1505
extern PNG_EXPORT(void,png_set_swap) PNGARG((png_structp png_ptr));
1508
#if defined(PNG_READ_PACK_SUPPORTED) || defined(PNG_WRITE_PACK_SUPPORTED)
1509
/* Use 1 byte per pixel in 1, 2, or 4-bit depth files. */
1510
extern PNG_EXPORT(void,png_set_packing) PNGARG((png_structp png_ptr));
1513
#if defined(PNG_READ_PACKSWAP_SUPPORTED) || defined(PNG_WRITE_PACKSWAP_SUPPORTED)
1514
/* Swap packing order of pixels in bytes. */
1515
extern PNG_EXPORT(void,png_set_packswap) PNGARG((png_structp png_ptr));
1518
#if defined(PNG_READ_SHIFT_SUPPORTED) || defined(PNG_WRITE_SHIFT_SUPPORTED)
1519
/* Converts files to legal bit depths. */
1520
extern PNG_EXPORT(void,png_set_shift) PNGARG((png_structp png_ptr,
1521
png_color_8p true_bits));
1524
#if defined(PNG_READ_INTERLACING_SUPPORTED) || \
1525
defined(PNG_WRITE_INTERLACING_SUPPORTED)
1526
/* Have the code handle the interlacing. Returns the number of passes. */
1527
extern PNG_EXPORT(int,png_set_interlace_handling) PNGARG((png_structp png_ptr));
1530
#if defined(PNG_READ_INVERT_SUPPORTED) || defined(PNG_WRITE_INVERT_SUPPORTED)
1531
/* Invert monochrome files */
1532
extern PNG_EXPORT(void,png_set_invert_mono) PNGARG((png_structp png_ptr));
1535
#if defined(PNG_READ_BACKGROUND_SUPPORTED)
1536
/* Handle alpha and tRNS by replacing with a background color. */
1537
#ifdef PNG_FLOATING_POINT_SUPPORTED
1538
extern PNG_EXPORT(void,png_set_background) PNGARG((png_structp png_ptr,
1539
png_color_16p background_color, int background_gamma_code,
1540
int need_expand, double background_gamma));
1542
#define PNG_BACKGROUND_GAMMA_UNKNOWN 0
1543
#define PNG_BACKGROUND_GAMMA_SCREEN 1
1544
#define PNG_BACKGROUND_GAMMA_FILE 2
1545
#define PNG_BACKGROUND_GAMMA_UNIQUE 3
1548
#if defined(PNG_READ_16_TO_8_SUPPORTED)
1549
/* strip the second byte of information from a 16-bit depth file. */
1550
extern PNG_EXPORT(void,png_set_strip_16) PNGARG((png_structp png_ptr));
1553
#if defined(PNG_READ_DITHER_SUPPORTED)
1554
/* Turn on dithering, and reduce the palette to the number of colors available. */
1555
extern PNG_EXPORT(void,png_set_dither) PNGARG((png_structp png_ptr,
1556
png_colorp palette, int num_palette, int maximum_colors,
1557
png_uint_16p histogram, int full_dither));
1560
#if defined(PNG_READ_GAMMA_SUPPORTED)
1561
/* Handle gamma correction. Screen_gamma=(display_exponent) */
1562
#ifdef PNG_FLOATING_POINT_SUPPORTED
1563
extern PNG_EXPORT(void,png_set_gamma) PNGARG((png_structp png_ptr,
1564
double screen_gamma, double default_file_gamma));
1568
#if defined(PNG_READ_EMPTY_PLTE_SUPPORTED) || \
1569
defined(PNG_WRITE_EMPTY_PLTE_SUPPORTED)
1570
/* Permit or disallow empty PLTE (0: not permitted, 1: permitted) */
1571
/* Deprecated and will be removed. Use png_permit_mng_features() instead. */
1572
extern PNG_EXPORT(void,png_permit_empty_plte) PNGARG((png_structp png_ptr,
1573
int empty_plte_permitted));
1576
#if defined(PNG_WRITE_FLUSH_SUPPORTED)
1577
/* Set how many lines between output flushes - 0 for no flushing */
1578
extern PNG_EXPORT(void,png_set_flush) PNGARG((png_structp png_ptr, int nrows));
1579
/* Flush the current PNG output buffer */
1580
extern PNG_EXPORT(void,png_write_flush) PNGARG((png_structp png_ptr));
1583
/* optional update palette with requested transformations */
1584
extern PNG_EXPORT(void,png_start_read_image) PNGARG((png_structp png_ptr));
1586
/* optional call to update the users info structure */
1587
extern PNG_EXPORT(void,png_read_update_info) PNGARG((png_structp png_ptr,
1588
png_infop info_ptr));
1590
#ifndef PNG_NO_SEQUENTIAL_READ_SUPPORTED
1591
/* read one or more rows of image data. */
1592
extern PNG_EXPORT(void,png_read_rows) PNGARG((png_structp png_ptr,
1593
png_bytepp row, png_bytepp display_row, png_uint_32 num_rows));
1596
#ifndef PNG_NO_SEQUENTIAL_READ_SUPPORTED
1597
/* read a row of data. */
1598
extern PNG_EXPORT(void,png_read_row) PNGARG((png_structp png_ptr,
1600
png_bytep display_row));
1603
#ifndef PNG_NO_SEQUENTIAL_READ_SUPPORTED
1604
/* read the whole image into memory at once. */
1605
extern PNG_EXPORT(void,png_read_image) PNGARG((png_structp png_ptr,
1609
/* write a row of image data */
1610
extern PNG_EXPORT(void,png_write_row) PNGARG((png_structp png_ptr,
1613
/* write a few rows of image data */
1614
extern PNG_EXPORT(void,png_write_rows) PNGARG((png_structp png_ptr,
1615
png_bytepp row, png_uint_32 num_rows));
1617
/* write the image data */
1618
extern PNG_EXPORT(void,png_write_image) PNGARG((png_structp png_ptr,
1621
/* writes the end of the PNG file. */
1622
extern PNG_EXPORT(void,png_write_end) PNGARG((png_structp png_ptr,
1623
png_infop info_ptr));
1625
#ifndef PNG_NO_SEQUENTIAL_READ_SUPPORTED
1626
/* read the end of the PNG file. */
1627
extern PNG_EXPORT(void,png_read_end) PNGARG((png_structp png_ptr,
1628
png_infop info_ptr));
1631
/* free any memory associated with the png_info_struct */
1632
extern PNG_EXPORT(void,png_destroy_info_struct) PNGARG((png_structp png_ptr,
1633
png_infopp info_ptr_ptr));
1635
/* free any memory associated with the png_struct and the png_info_structs */
1636
extern PNG_EXPORT(void,png_destroy_read_struct) PNGARG((png_structpp
1637
png_ptr_ptr, png_infopp info_ptr_ptr, png_infopp end_info_ptr_ptr));
1639
/* free all memory used by the read (old method - NOT DLL EXPORTED) */
1640
extern void png_read_destroy PNGARG((png_structp png_ptr, png_infop info_ptr,
1641
png_infop end_info_ptr));
1643
/* free any memory associated with the png_struct and the png_info_structs */
1644
extern PNG_EXPORT(void,png_destroy_write_struct)
1645
PNGARG((png_structpp png_ptr_ptr, png_infopp info_ptr_ptr));
1647
/* free any memory used in png_ptr struct (old method - NOT DLL EXPORTED) */
1648
extern void png_write_destroy PNGARG((png_structp png_ptr));
1650
/* set the libpng method of handling chunk CRC errors */
1651
extern PNG_EXPORT(void,png_set_crc_action) PNGARG((png_structp png_ptr,
1652
int crit_action, int ancil_action));
1654
/* Values for png_set_crc_action() to say how to handle CRC errors in
1655
* ancillary and critical chunks, and whether to use the data contained
1656
* therein. Note that it is impossible to "discard" data in a critical
1657
* chunk. For versions prior to 0.90, the action was always error/quit,
1658
* whereas in version 0.90 and later, the action for CRC errors in ancillary
1659
* chunks is warn/discard. These values should NOT be changed.
1661
* value action:critical action:ancillary
1663
#define PNG_CRC_DEFAULT 0 /* error/quit warn/discard data */
1664
#define PNG_CRC_ERROR_QUIT 1 /* error/quit error/quit */
1665
#define PNG_CRC_WARN_DISCARD 2 /* (INVALID) warn/discard data */
1666
#define PNG_CRC_WARN_USE 3 /* warn/use data warn/use data */
1667
#define PNG_CRC_QUIET_USE 4 /* quiet/use data quiet/use data */
1668
#define PNG_CRC_NO_CHANGE 5 /* use current value use current value */
1670
/* These functions give the user control over the scan-line filtering in
1671
* libpng and the compression methods used by zlib. These functions are
1672
* mainly useful for testing, as the defaults should work with most users.
1673
* Those users who are tight on memory or want faster performance at the
1674
* expense of compression can modify them. See the compression library
1675
* header file (zlib.h) for an explination of the compression functions.
1678
/* set the filtering method(s) used by libpng. Currently, the only valid
1679
* value for "method" is 0.
1681
extern PNG_EXPORT(void,png_set_filter) PNGARG((png_structp png_ptr, int method,
1684
/* Flags for png_set_filter() to say which filters to use. The flags
1685
* are chosen so that they don't conflict with real filter types
1686
* below, in case they are supplied instead of the #defined constants.
1687
* These values should NOT be changed.
1689
#define PNG_NO_FILTERS 0x00
1690
#define PNG_FILTER_NONE 0x08
1691
#define PNG_FILTER_SUB 0x10
1692
#define PNG_FILTER_UP 0x20
1693
#define PNG_FILTER_AVG 0x40
1694
#define PNG_FILTER_PAETH 0x80
1695
#define PNG_ALL_FILTERS (PNG_FILTER_NONE | PNG_FILTER_SUB | PNG_FILTER_UP | \
1696
PNG_FILTER_AVG | PNG_FILTER_PAETH)
1698
/* Filter values (not flags) - used in pngwrite.c, pngwutil.c for now.
1699
* These defines should NOT be changed.
1701
#define PNG_FILTER_VALUE_NONE 0
1702
#define PNG_FILTER_VALUE_SUB 1
1703
#define PNG_FILTER_VALUE_UP 2
1704
#define PNG_FILTER_VALUE_AVG 3
1705
#define PNG_FILTER_VALUE_PAETH 4
1706
#define PNG_FILTER_VALUE_LAST 5
1708
#if defined(PNG_WRITE_WEIGHTED_FILTER_SUPPORTED) /* EXPERIMENTAL */
1709
/* The "heuristic_method" is given by one of the PNG_FILTER_HEURISTIC_
1710
* defines, either the default (minimum-sum-of-absolute-differences), or
1711
* the experimental method (weighted-minimum-sum-of-absolute-differences).
1713
* Weights are factors >= 1.0, indicating how important it is to keep the
1714
* filter type consistent between rows. Larger numbers mean the current
1715
* filter is that many times as likely to be the same as the "num_weights"
1716
* previous filters. This is cumulative for each previous row with a weight.
1717
* There needs to be "num_weights" values in "filter_weights", or it can be
1718
* NULL if the weights aren't being specified. Weights have no influence on
1719
* the selection of the first row filter. Well chosen weights can (in theory)
1720
* improve the compression for a given image.
1722
* Costs are factors >= 1.0 indicating the relative decoding costs of a
1723
* filter type. Higher costs indicate more decoding expense, and are
1724
* therefore less likely to be selected over a filter with lower computational
1725
* costs. There needs to be a value in "filter_costs" for each valid filter
1726
* type (given by PNG_FILTER_VALUE_LAST), or it can be NULL if you aren't
1727
* setting the costs. Costs try to improve the speed of decompression without
1728
* unduly increasing the compressed image size.
1730
* A negative weight or cost indicates the default value is to be used, and
1731
* values in the range [0.0, 1.0) indicate the value is to remain unchanged.
1732
* The default values for both weights and costs are currently 1.0, but may
1733
* change if good general weighting/cost heuristics can be found. If both
1734
* the weights and costs are set to 1.0, this degenerates the WEIGHTED method
1735
* to the UNWEIGHTED method, but with added encoding time/computation.
1737
#ifdef PNG_FLOATING_POINT_SUPPORTED
1738
extern PNG_EXPORT(void,png_set_filter_heuristics) PNGARG((png_structp png_ptr,
1739
int heuristic_method, int num_weights, png_doublep filter_weights,
1740
png_doublep filter_costs));
1742
#endif /* PNG_WRITE_WEIGHTED_FILTER_SUPPORTED */
1744
/* Heuristic used for row filter selection. These defines should NOT be
1747
#define PNG_FILTER_HEURISTIC_DEFAULT 0 /* Currently "UNWEIGHTED" */
1748
#define PNG_FILTER_HEURISTIC_UNWEIGHTED 1 /* Used by libpng < 0.95 */
1749
#define PNG_FILTER_HEURISTIC_WEIGHTED 2 /* Experimental feature */
1750
#define PNG_FILTER_HEURISTIC_LAST 3 /* Not a valid value */
1752
/* Set the library compression level. Currently, valid values range from
1753
* 0 - 9, corresponding directly to the zlib compression levels 0 - 9
1754
* (0 - no compression, 9 - "maximal" compression). Note that tests have
1755
* shown that zlib compression levels 3-6 usually perform as well as level 9
1756
* for PNG images, and do considerably fewer caclulations. In the future,
1757
* these values may not correspond directly to the zlib compression levels.
1759
extern PNG_EXPORT(void,png_set_compression_level) PNGARG((png_structp png_ptr,
1762
extern PNG_EXPORT(void,png_set_compression_mem_level)
1763
PNGARG((png_structp png_ptr, int mem_level));
1765
extern PNG_EXPORT(void,png_set_compression_strategy)
1766
PNGARG((png_structp png_ptr, int strategy));
1768
extern PNG_EXPORT(void,png_set_compression_window_bits)
1769
PNGARG((png_structp png_ptr, int window_bits));
1771
extern PNG_EXPORT(void,png_set_compression_method) PNGARG((png_structp png_ptr,
1774
/* These next functions are called for input/output, memory, and error
1775
* handling. They are in the file pngrio.c, pngwio.c, and pngerror.c,
1776
* and call standard C I/O routines such as fread(), fwrite(), and
1777
* fprintf(). These functions can be made to use other I/O routines
1778
* at run time for those applications that need to handle I/O in a
1779
* different manner by calling png_set_???_fn(). See libpng.txt for
1783
#if !defined(PNG_NO_STDIO)
1784
/* Initialize the input/output for the PNG file to the default functions. */
1785
extern PNG_EXPORT(void,png_init_io) PNGARG((png_structp png_ptr, png_FILE_p fp));
1788
/* Replace the (error and abort), and warning functions with user
1789
* supplied functions. If no messages are to be printed you must still
1790
* write and use replacement functions. The replacement error_fn should
1791
* still do a longjmp to the last setjmp location if you are using this
1792
* method of error handling. If error_fn or warning_fn is NULL, the
1793
* default function will be used.
1796
extern PNG_EXPORT(void,png_set_error_fn) PNGARG((png_structp png_ptr,
1797
png_voidp error_ptr, png_error_ptr error_fn, png_error_ptr warning_fn));
1799
/* Return the user pointer associated with the error functions */
1800
extern PNG_EXPORT(png_voidp,png_get_error_ptr) PNGARG((png_structp png_ptr));
1802
/* Replace the default data output functions with a user supplied one(s).
1803
* If buffered output is not used, then output_flush_fn can be set to NULL.
1804
* If PNG_WRITE_FLUSH_SUPPORTED is not defined at libpng compile time
1805
* output_flush_fn will be ignored (and thus can be NULL).
1807
extern PNG_EXPORT(void,png_set_write_fn) PNGARG((png_structp png_ptr,
1808
png_voidp io_ptr, png_rw_ptr write_data_fn, png_flush_ptr output_flush_fn));
1810
/* Replace the default data input function with a user supplied one. */
1811
extern PNG_EXPORT(void,png_set_read_fn) PNGARG((png_structp png_ptr,
1812
png_voidp io_ptr, png_rw_ptr read_data_fn));
1814
/* Return the user pointer associated with the I/O functions */
1815
extern PNG_EXPORT(png_voidp,png_get_io_ptr) PNGARG((png_structp png_ptr));
1817
extern PNG_EXPORT(void,png_set_read_status_fn) PNGARG((png_structp png_ptr,
1818
png_read_status_ptr read_row_fn));
1820
extern PNG_EXPORT(void,png_set_write_status_fn) PNGARG((png_structp png_ptr,
1821
png_write_status_ptr write_row_fn));
1823
#ifdef PNG_USER_MEM_SUPPORTED
1824
/* Replace the default memory allocation functions with user supplied one(s). */
1825
extern PNG_EXPORT(void,png_set_mem_fn) PNGARG((png_structp png_ptr,
1826
png_voidp mem_ptr, png_malloc_ptr malloc_fn, png_free_ptr free_fn));
1827
/* Return the user pointer associated with the memory functions */
1828
extern PNG_EXPORT(png_voidp,png_get_mem_ptr) PNGARG((png_structp png_ptr));
1831
#if defined(PNG_READ_USER_TRANSFORM_SUPPORTED) || \
1832
defined(PNG_LEGACY_SUPPORTED)
1833
extern PNG_EXPORT(void,png_set_read_user_transform_fn) PNGARG((png_structp
1834
png_ptr, png_user_transform_ptr read_user_transform_fn));
1837
#if defined(PNG_WRITE_USER_TRANSFORM_SUPPORTED) || \
1838
defined(PNG_LEGACY_SUPPORTED)
1839
extern PNG_EXPORT(void,png_set_write_user_transform_fn) PNGARG((png_structp
1840
png_ptr, png_user_transform_ptr write_user_transform_fn));
1843
#if defined(PNG_READ_USER_TRANSFORM_SUPPORTED) || \
1844
defined(PNG_WRITE_USER_TRANSFORM_SUPPORTED) || \
1845
defined(PNG_LEGACY_SUPPORTED)
1846
extern PNG_EXPORT(void,png_set_user_transform_info) PNGARG((png_structp
1847
png_ptr, png_voidp user_transform_ptr, int user_transform_depth,
1848
int user_transform_channels));
1849
/* Return the user pointer associated with the user transform functions */
1850
extern PNG_EXPORT(png_voidp,png_get_user_transform_ptr)
1851
PNGARG((png_structp png_ptr));
1854
#ifdef PNG_USER_CHUNKS_SUPPORTED
1855
extern PNG_EXPORT(void,png_set_read_user_chunk_fn) PNGARG((png_structp png_ptr,
1856
png_voidp user_chunk_ptr, png_user_chunk_ptr read_user_chunk_fn));
1857
extern PNG_EXPORT(png_voidp,png_get_user_chunk_ptr) PNGARG((png_structp
1861
#ifdef PNG_PROGRESSIVE_READ_SUPPORTED
1862
/* Sets the function callbacks for the push reader, and a pointer to a
1863
* user-defined structure available to the callback functions.
1865
extern PNG_EXPORT(void,png_set_progressive_read_fn) PNGARG((png_structp png_ptr,
1866
png_voidp progressive_ptr,
1867
png_progressive_info_ptr info_fn, png_progressive_row_ptr row_fn,
1868
png_progressive_end_ptr end_fn));
1870
/* returns the user pointer associated with the push read functions */
1871
extern PNG_EXPORT(png_voidp,png_get_progressive_ptr)
1872
PNGARG((png_structp png_ptr));
1874
/* function to be called when data becomes available */
1875
extern PNG_EXPORT(void,png_process_data) PNGARG((png_structp png_ptr,
1876
png_infop info_ptr, png_bytep buffer, png_size_t buffer_size));
1878
/* function that combines rows. Not very much different than the
1879
* png_combine_row() call. Is this even used?????
1881
extern PNG_EXPORT(void,png_progressive_combine_row) PNGARG((png_structp png_ptr,
1882
png_bytep old_row, png_bytep new_row));
1883
#endif /* PNG_PROGRESSIVE_READ_SUPPORTED */
1885
extern PNG_EXPORT(png_voidp,png_malloc) PNGARG((png_structp png_ptr,
1888
#if defined(PNG_1_0_X)
1889
# define png_malloc_warn png_malloc
1891
/* Added at libpng version 1.2.4 */
1892
extern PNG_EXPORT(png_voidp,png_malloc_warn) PNGARG((png_structp png_ptr,
1896
/* frees a pointer allocated by png_malloc() */
1897
extern PNG_EXPORT(void,png_free) PNGARG((png_structp png_ptr, png_voidp ptr));
1899
#if defined(PNG_1_0_X)
1900
/* Function to allocate memory for zlib. */
1901
extern PNG_EXPORT(voidpf,png_zalloc) PNGARG((voidpf png_ptr, uInt items,
1904
/* Function to free memory for zlib */
1905
extern PNG_EXPORT(void,png_zfree) PNGARG((voidpf png_ptr, voidpf ptr));
1908
/* Free data that was allocated internally */
1909
extern PNG_EXPORT(void,png_free_data) PNGARG((png_structp png_ptr,
1910
png_infop info_ptr, png_uint_32 free_me, int num));
1911
#ifdef PNG_FREE_ME_SUPPORTED
1912
/* Reassign responsibility for freeing existing data, whether allocated
1913
* by libpng or by the application */
1914
extern PNG_EXPORT(void,png_data_freer) PNGARG((png_structp png_ptr,
1915
png_infop info_ptr, int freer, png_uint_32 mask));
1917
/* assignments for png_data_freer */
1918
#define PNG_DESTROY_WILL_FREE_DATA 1
1919
#define PNG_SET_WILL_FREE_DATA 1
1920
#define PNG_USER_WILL_FREE_DATA 2
1921
/* Flags for png_ptr->free_me and info_ptr->free_me */
1922
#define PNG_FREE_HIST 0x0008
1923
#define PNG_FREE_ICCP 0x0010
1924
#define PNG_FREE_SPLT 0x0020
1925
#define PNG_FREE_ROWS 0x0040
1926
#define PNG_FREE_PCAL 0x0080
1927
#define PNG_FREE_SCAL 0x0100
1928
#define PNG_FREE_UNKN 0x0200
1929
#define PNG_FREE_LIST 0x0400
1930
#define PNG_FREE_PLTE 0x1000
1931
#define PNG_FREE_TRNS 0x2000
1932
#define PNG_FREE_TEXT 0x4000
1933
#define PNG_FREE_ALL 0x7fff
1934
#define PNG_FREE_MUL 0x4220 /* PNG_FREE_SPLT|PNG_FREE_TEXT|PNG_FREE_UNKN */
1936
#ifdef PNG_USER_MEM_SUPPORTED
1937
extern PNG_EXPORT(png_voidp,png_malloc_default) PNGARG((png_structp png_ptr,
1939
extern PNG_EXPORT(void,png_free_default) PNGARG((png_structp png_ptr,
1943
extern PNG_EXPORT(png_voidp,png_memcpy_check) PNGARG((png_structp png_ptr,
1944
png_voidp s1, png_voidp s2, png_uint_32 size));
1946
extern PNG_EXPORT(png_voidp,png_memset_check) PNGARG((png_structp png_ptr,
1947
png_voidp s1, int value, png_uint_32 size));
1949
#if defined(USE_FAR_KEYWORD) /* memory model conversion function */
1950
extern void *png_far_to_near PNGARG((png_structp png_ptr,png_voidp ptr,
1952
#endif /* USE_FAR_KEYWORD */
1954
/* Fatal error in PNG image of libpng - can't continue */
1955
extern PNG_EXPORT(void,png_error) PNGARG((png_structp png_ptr,
1956
png_const_charp error_message));
1958
/* The same, but the chunk name is prepended to the error string. */
1959
extern PNG_EXPORT(void,png_chunk_error) PNGARG((png_structp png_ptr,
1960
png_const_charp error_message));
1962
/* Non-fatal error in libpng. Can continue, but may have a problem. */
1963
extern PNG_EXPORT(void,png_warning) PNGARG((png_structp png_ptr,
1964
png_const_charp warning_message));
1966
/* Non-fatal error in libpng, chunk name is prepended to message. */
1967
extern PNG_EXPORT(void,png_chunk_warning) PNGARG((png_structp png_ptr,
1968
png_const_charp warning_message));
1970
/* The png_set_<chunk> functions are for storing values in the png_info_struct.
1971
* Similarly, the png_get_<chunk> calls are used to read values from the
1972
* png_info_struct, either storing the parameters in the passed variables, or
1973
* setting pointers into the png_info_struct where the data is stored. The
1974
* png_get_<chunk> functions return a non-zero value if the data was available
1975
* in info_ptr, or return zero and do not change any of the parameters if the
1976
* data was not available.
1978
* These functions should be used instead of directly accessing png_info
1979
* to avoid problems with future changes in the size and internal layout of
1982
/* Returns "flag" if chunk data is valid in info_ptr. */
1983
extern PNG_EXPORT(png_uint_32,png_get_valid) PNGARG((png_structp png_ptr,
1984
png_infop info_ptr, png_uint_32 flag));
1986
/* Returns number of bytes needed to hold a transformed row. */
1987
extern PNG_EXPORT(png_uint_32,png_get_rowbytes) PNGARG((png_structp png_ptr,
1988
png_infop info_ptr));
1990
#if defined(PNG_INFO_IMAGE_SUPPORTED)
1991
/* Returns row_pointers, which is an array of pointers to scanlines that was
1992
returned from png_read_png(). */
1993
extern PNG_EXPORT(png_bytepp,png_get_rows) PNGARG((png_structp png_ptr,
1994
png_infop info_ptr));
1995
/* Set row_pointers, which is an array of pointers to scanlines for use
1996
by png_write_png(). */
1997
extern PNG_EXPORT(void,png_set_rows) PNGARG((png_structp png_ptr,
1998
png_infop info_ptr, png_bytepp row_pointers));
2001
/* Returns number of color channels in image. */
2002
extern PNG_EXPORT(png_byte,png_get_channels) PNGARG((png_structp png_ptr,
2003
png_infop info_ptr));
2005
#ifdef PNG_EASY_ACCESS_SUPPORTED
2006
/* Returns image width in pixels. */
2007
extern PNG_EXPORT(png_uint_32, png_get_image_width) PNGARG((png_structp
2008
png_ptr, png_infop info_ptr));
2010
/* Returns image height in pixels. */
2011
extern PNG_EXPORT(png_uint_32, png_get_image_height) PNGARG((png_structp
2012
png_ptr, png_infop info_ptr));
2014
/* Returns image bit_depth. */
2015
extern PNG_EXPORT(png_byte, png_get_bit_depth) PNGARG((png_structp
2016
png_ptr, png_infop info_ptr));
2018
/* Returns image color_type. */
2019
extern PNG_EXPORT(png_byte, png_get_color_type) PNGARG((png_structp
2020
png_ptr, png_infop info_ptr));
2022
/* Returns image filter_type. */
2023
extern PNG_EXPORT(png_byte, png_get_filter_type) PNGARG((png_structp
2024
png_ptr, png_infop info_ptr));
2026
/* Returns image interlace_type. */
2027
extern PNG_EXPORT(png_byte, png_get_interlace_type) PNGARG((png_structp
2028
png_ptr, png_infop info_ptr));
2030
/* Returns image compression_type. */
2031
extern PNG_EXPORT(png_byte, png_get_compression_type) PNGARG((png_structp
2032
png_ptr, png_infop info_ptr));
2034
/* Returns image resolution in pixels per meter, from pHYs chunk data. */
2035
extern PNG_EXPORT(png_uint_32, png_get_pixels_per_meter) PNGARG((png_structp
2036
png_ptr, png_infop info_ptr));
2037
extern PNG_EXPORT(png_uint_32, png_get_x_pixels_per_meter) PNGARG((png_structp
2038
png_ptr, png_infop info_ptr));
2039
extern PNG_EXPORT(png_uint_32, png_get_y_pixels_per_meter) PNGARG((png_structp
2040
png_ptr, png_infop info_ptr));
2042
/* Returns pixel aspect ratio, computed from pHYs chunk data. */
2043
#ifdef PNG_FLOATING_POINT_SUPPORTED
2044
extern PNG_EXPORT(float, png_get_pixel_aspect_ratio) PNGARG((png_structp
2045
png_ptr, png_infop info_ptr));
2048
/* Returns image x, y offset in pixels or microns, from oFFs chunk data. */
2049
extern PNG_EXPORT(png_int_32, png_get_x_offset_pixels) PNGARG((png_structp
2050
png_ptr, png_infop info_ptr));
2051
extern PNG_EXPORT(png_int_32, png_get_y_offset_pixels) PNGARG((png_structp
2052
png_ptr, png_infop info_ptr));
2053
extern PNG_EXPORT(png_int_32, png_get_x_offset_microns) PNGARG((png_structp
2054
png_ptr, png_infop info_ptr));
2055
extern PNG_EXPORT(png_int_32, png_get_y_offset_microns) PNGARG((png_structp
2056
png_ptr, png_infop info_ptr));
2058
#endif /* PNG_EASY_ACCESS_SUPPORTED */
2060
/* Returns pointer to signature string read from PNG header */
2061
extern PNG_EXPORT(png_bytep,png_get_signature) PNGARG((png_structp png_ptr,
2062
png_infop info_ptr));
2064
#if defined(PNG_bKGD_SUPPORTED)
2065
extern PNG_EXPORT(png_uint_32,png_get_bKGD) PNGARG((png_structp png_ptr,
2066
png_infop info_ptr, png_color_16p *background));
2069
#if defined(PNG_bKGD_SUPPORTED)
2070
extern PNG_EXPORT(void,png_set_bKGD) PNGARG((png_structp png_ptr,
2071
png_infop info_ptr, png_color_16p background));
2074
#if defined(PNG_cHRM_SUPPORTED)
2075
#ifdef PNG_FLOATING_POINT_SUPPORTED
2076
extern PNG_EXPORT(png_uint_32,png_get_cHRM) PNGARG((png_structp png_ptr,
2077
png_infop info_ptr, double *white_x, double *white_y, double *red_x,
2078
double *red_y, double *green_x, double *green_y, double *blue_x,
2081
#ifdef PNG_FIXED_POINT_SUPPORTED
2082
extern PNG_EXPORT(png_uint_32,png_get_cHRM_fixed) PNGARG((png_structp png_ptr,
2083
png_infop info_ptr, png_fixed_point *int_white_x, png_fixed_point
2084
*int_white_y, png_fixed_point *int_red_x, png_fixed_point *int_red_y,
2085
png_fixed_point *int_green_x, png_fixed_point *int_green_y, png_fixed_point
2086
*int_blue_x, png_fixed_point *int_blue_y));
2090
#if defined(PNG_cHRM_SUPPORTED)
2091
#ifdef PNG_FLOATING_POINT_SUPPORTED
2092
extern PNG_EXPORT(void,png_set_cHRM) PNGARG((png_structp png_ptr,
2093
png_infop info_ptr, double white_x, double white_y, double red_x,
2094
double red_y, double green_x, double green_y, double blue_x, double blue_y));
2096
#ifdef PNG_FIXED_POINT_SUPPORTED
2097
extern PNG_EXPORT(void,png_set_cHRM_fixed) PNGARG((png_structp png_ptr,
2098
png_infop info_ptr, png_fixed_point int_white_x, png_fixed_point int_white_y,
2099
png_fixed_point int_red_x, png_fixed_point int_red_y, png_fixed_point
2100
int_green_x, png_fixed_point int_green_y, png_fixed_point int_blue_x,
2101
png_fixed_point int_blue_y));
2105
#if defined(PNG_gAMA_SUPPORTED)
2106
#ifdef PNG_FLOATING_POINT_SUPPORTED
2107
extern PNG_EXPORT(png_uint_32,png_get_gAMA) PNGARG((png_structp png_ptr,
2108
png_infop info_ptr, double *file_gamma));
2110
extern PNG_EXPORT(png_uint_32,png_get_gAMA_fixed) PNGARG((png_structp png_ptr,
2111
png_infop info_ptr, png_fixed_point *int_file_gamma));
2114
#if defined(PNG_gAMA_SUPPORTED)
2115
#ifdef PNG_FLOATING_POINT_SUPPORTED
2116
extern PNG_EXPORT(void,png_set_gAMA) PNGARG((png_structp png_ptr,
2117
png_infop info_ptr, double file_gamma));
2119
extern PNG_EXPORT(void,png_set_gAMA_fixed) PNGARG((png_structp png_ptr,
2120
png_infop info_ptr, png_fixed_point int_file_gamma));
2123
#if defined(PNG_hIST_SUPPORTED)
2124
extern PNG_EXPORT(png_uint_32,png_get_hIST) PNGARG((png_structp png_ptr,
2125
png_infop info_ptr, png_uint_16p *hist));
2128
#if defined(PNG_hIST_SUPPORTED)
2129
extern PNG_EXPORT(void,png_set_hIST) PNGARG((png_structp png_ptr,
2130
png_infop info_ptr, png_uint_16p hist));
2133
extern PNG_EXPORT(png_uint_32,png_get_IHDR) PNGARG((png_structp png_ptr,
2134
png_infop info_ptr, png_uint_32 *width, png_uint_32 *height,
2135
int *bit_depth, int *color_type, int *interlace_method,
2136
int *compression_method, int *filter_method));
2138
extern PNG_EXPORT(void,png_set_IHDR) PNGARG((png_structp png_ptr,
2139
png_infop info_ptr, png_uint_32 width, png_uint_32 height, int bit_depth,
2140
int color_type, int interlace_method, int compression_method,
2141
int filter_method));
2143
#if defined(PNG_oFFs_SUPPORTED)
2144
extern PNG_EXPORT(png_uint_32,png_get_oFFs) PNGARG((png_structp png_ptr,
2145
png_infop info_ptr, png_int_32 *offset_x, png_int_32 *offset_y,
2149
#if defined(PNG_oFFs_SUPPORTED)
2150
extern PNG_EXPORT(void,png_set_oFFs) PNGARG((png_structp png_ptr,
2151
png_infop info_ptr, png_int_32 offset_x, png_int_32 offset_y,
2155
#if defined(PNG_pCAL_SUPPORTED)
2156
extern PNG_EXPORT(png_uint_32,png_get_pCAL) PNGARG((png_structp png_ptr,
2157
png_infop info_ptr, png_charp *purpose, png_int_32 *X0, png_int_32 *X1,
2158
int *type, int *nparams, png_charp *units, png_charpp *params));
2161
#if defined(PNG_pCAL_SUPPORTED)
2162
extern PNG_EXPORT(void,png_set_pCAL) PNGARG((png_structp png_ptr,
2163
png_infop info_ptr, png_charp purpose, png_int_32 X0, png_int_32 X1,
2164
int type, int nparams, png_charp units, png_charpp params));
2167
#if defined(PNG_pHYs_SUPPORTED)
2168
extern PNG_EXPORT(png_uint_32,png_get_pHYs) PNGARG((png_structp png_ptr,
2169
png_infop info_ptr, png_uint_32 *res_x, png_uint_32 *res_y, int *unit_type));
2172
#if defined(PNG_pHYs_SUPPORTED)
2173
extern PNG_EXPORT(void,png_set_pHYs) PNGARG((png_structp png_ptr,
2174
png_infop info_ptr, png_uint_32 res_x, png_uint_32 res_y, int unit_type));
2177
extern PNG_EXPORT(png_uint_32,png_get_PLTE) PNGARG((png_structp png_ptr,
2178
png_infop info_ptr, png_colorp *palette, int *num_palette));
2180
extern PNG_EXPORT(void,png_set_PLTE) PNGARG((png_structp png_ptr,
2181
png_infop info_ptr, png_colorp palette, int num_palette));
2183
#if defined(PNG_sBIT_SUPPORTED)
2184
extern PNG_EXPORT(png_uint_32,png_get_sBIT) PNGARG((png_structp png_ptr,
2185
png_infop info_ptr, png_color_8p *sig_bit));
2188
#if defined(PNG_sBIT_SUPPORTED)
2189
extern PNG_EXPORT(void,png_set_sBIT) PNGARG((png_structp png_ptr,
2190
png_infop info_ptr, png_color_8p sig_bit));
2193
#if defined(PNG_sRGB_SUPPORTED)
2194
extern PNG_EXPORT(png_uint_32,png_get_sRGB) PNGARG((png_structp png_ptr,
2195
png_infop info_ptr, int *intent));
2198
#if defined(PNG_sRGB_SUPPORTED)
2199
extern PNG_EXPORT(void,png_set_sRGB) PNGARG((png_structp png_ptr,
2200
png_infop info_ptr, int intent));
2201
extern PNG_EXPORT(void,png_set_sRGB_gAMA_and_cHRM) PNGARG((png_structp png_ptr,
2202
png_infop info_ptr, int intent));
2205
#if defined(PNG_iCCP_SUPPORTED)
2206
extern PNG_EXPORT(png_uint_32,png_get_iCCP) PNGARG((png_structp png_ptr,
2207
png_infop info_ptr, png_charpp name, int *compression_type,
2208
png_charpp profile, png_uint_32 *proflen));
2209
/* Note to maintainer: profile should be png_bytepp */
2212
#if defined(PNG_iCCP_SUPPORTED)
2213
extern PNG_EXPORT(void,png_set_iCCP) PNGARG((png_structp png_ptr,
2214
png_infop info_ptr, png_charp name, int compression_type,
2215
png_charp profile, png_uint_32 proflen));
2216
/* Note to maintainer: profile should be png_bytep */
2219
#if defined(PNG_sPLT_SUPPORTED)
2220
extern PNG_EXPORT(png_uint_32,png_get_sPLT) PNGARG((png_structp png_ptr,
2221
png_infop info_ptr, png_sPLT_tpp entries));
2224
#if defined(PNG_sPLT_SUPPORTED)
2225
extern PNG_EXPORT(void,png_set_sPLT) PNGARG((png_structp png_ptr,
2226
png_infop info_ptr, png_sPLT_tp entries, int nentries));
2229
#if defined(PNG_TEXT_SUPPORTED)
2230
/* png_get_text also returns the number of text chunks in *num_text */
2231
extern PNG_EXPORT(png_uint_32,png_get_text) PNGARG((png_structp png_ptr,
2232
png_infop info_ptr, png_textp *text_ptr, int *num_text));
2236
* Note while png_set_text() will accept a structure whose text,
2237
* language, and translated keywords are NULL pointers, the structure
2238
* returned by png_get_text will always contain regular
2239
* zero-terminated C strings. They might be empty strings but
2240
* they will never be NULL pointers.
2243
#if defined(PNG_TEXT_SUPPORTED)
2244
extern PNG_EXPORT(void,png_set_text) PNGARG((png_structp png_ptr,
2245
png_infop info_ptr, png_textp text_ptr, int num_text));
2248
#if defined(PNG_tIME_SUPPORTED)
2249
extern PNG_EXPORT(png_uint_32,png_get_tIME) PNGARG((png_structp png_ptr,
2250
png_infop info_ptr, png_timep *mod_time));
2253
#if defined(PNG_tIME_SUPPORTED)
2254
extern PNG_EXPORT(void,png_set_tIME) PNGARG((png_structp png_ptr,
2255
png_infop info_ptr, png_timep mod_time));
2258
#if defined(PNG_tRNS_SUPPORTED)
2259
extern PNG_EXPORT(png_uint_32,png_get_tRNS) PNGARG((png_structp png_ptr,
2260
png_infop info_ptr, png_bytep *trans, int *num_trans,
2261
png_color_16p *trans_values));
2264
#if defined(PNG_tRNS_SUPPORTED)
2265
extern PNG_EXPORT(void,png_set_tRNS) PNGARG((png_structp png_ptr,
2266
png_infop info_ptr, png_bytep trans, int num_trans,
2267
png_color_16p trans_values));
2270
#if defined(PNG_tRNS_SUPPORTED)
2273
#if defined(PNG_sCAL_SUPPORTED)
2274
#ifdef PNG_FLOATING_POINT_SUPPORTED
2275
extern PNG_EXPORT(png_uint_32,png_get_sCAL) PNGARG((png_structp png_ptr,
2276
png_infop info_ptr, int *unit, double *width, double *height));
2278
#ifdef PNG_FIXED_POINT_SUPPORTED
2279
extern PNG_EXPORT(png_uint_32,png_get_sCAL_s) PNGARG((png_structp png_ptr,
2280
png_infop info_ptr, int *unit, png_charpp swidth, png_charpp sheight));
2283
#endif /* PNG_sCAL_SUPPORTED */
2285
#if defined(PNG_sCAL_SUPPORTED)
2286
#ifdef PNG_FLOATING_POINT_SUPPORTED
2287
extern PNG_EXPORT(void,png_set_sCAL) PNGARG((png_structp png_ptr,
2288
png_infop info_ptr, int unit, double width, double height));
2290
#ifdef PNG_FIXED_POINT_SUPPORTED
2291
extern PNG_EXPORT(void,png_set_sCAL_s) PNGARG((png_structp png_ptr,
2292
png_infop info_ptr, int unit, png_charp swidth, png_charp sheight));
2294
#endif /* PNG_sCAL_SUPPORTED || PNG_WRITE_sCAL_SUPPORTED */
2296
#if defined(PNG_UNKNOWN_CHUNKS_SUPPORTED)
2297
/* provide a list of chunks and how they are to be handled, if the built-in
2298
handling or default unknown chunk handling is not desired. Any chunks not
2299
listed will be handled in the default manner. The IHDR and IEND chunks
2301
keep = 0: follow default behavour
2303
= 2: keep only if safe-to-copy
2304
= 3: keep even if unsafe-to-copy
2306
extern PNG_EXPORT(void, png_set_keep_unknown_chunks) PNGARG((png_structp
2307
png_ptr, int keep, png_bytep chunk_list, int num_chunks));
2308
extern PNG_EXPORT(void, png_set_unknown_chunks) PNGARG((png_structp png_ptr,
2309
png_infop info_ptr, png_unknown_chunkp unknowns, int num_unknowns));
2310
extern PNG_EXPORT(void, png_set_unknown_chunk_location)
2311
PNGARG((png_structp png_ptr, png_infop info_ptr, int chunk, int location));
2312
extern PNG_EXPORT(png_uint_32,png_get_unknown_chunks) PNGARG((png_structp
2313
png_ptr, png_infop info_ptr, png_unknown_chunkpp entries));
2315
#ifdef PNG_HANDLE_AS_UNKNOWN_SUPPORTED
2316
PNG_EXPORT(int,png_handle_as_unknown) PNGARG((png_structp png_ptr, png_bytep
2320
/* Png_free_data() will turn off the "valid" flag for anything it frees.
2321
If you need to turn it off for a chunk that your application has freed,
2322
you can use png_set_invalid(png_ptr, info_ptr, PNG_INFO_CHNK); */
2323
extern PNG_EXPORT(void, png_set_invalid) PNGARG((png_structp png_ptr,
2324
png_infop info_ptr, int mask));
2326
#if defined(PNG_INFO_IMAGE_SUPPORTED)
2327
/* The "params" pointer is currently not used and is for future expansion. */
2328
extern PNG_EXPORT(void, png_read_png) PNGARG((png_structp png_ptr,
2332
extern PNG_EXPORT(void, png_write_png) PNGARG((png_structp png_ptr,
2338
/* Define PNG_DEBUG at compile time for debugging information. Higher
2339
* numbers for PNG_DEBUG mean more debugging information. This has
2340
* only been added since version 0.95 so it is not implemented throughout
2341
* libpng yet, but more support will be added as needed.
2345
#if !defined(PNG_DEBUG_FILE) && defined(_MSC_VER)
2348
#define png_debug(l,m) _RPT0(_CRT_WARN,m)
2349
#define png_debug1(l,m,p1) _RPT1(_CRT_WARN,m,p1)
2350
#define png_debug2(l,m,p1,p2) _RPT2(_CRT_WARN,m,p1,p2)
2352
#else /* PNG_DEBUG_FILE || !_MSC_VER */
2353
#ifndef PNG_DEBUG_FILE
2354
#define PNG_DEBUG_FILE stderr
2355
#endif /* PNG_DEBUG_FILE */
2357
#define png_debug(l,m) \
2360
fprintf(PNG_DEBUG_FILE,"%s"m,(num_tabs==1 ? "\t" : \
2361
(num_tabs==2 ? "\t\t":(num_tabs>2 ? "\t\t\t":"")))); \
2363
#define png_debug1(l,m,p1) \
2366
fprintf(PNG_DEBUG_FILE,"%s"m,(num_tabs==1 ? "\t" : \
2367
(num_tabs==2 ? "\t\t":(num_tabs>2 ? "\t\t\t":""))),p1); \
2369
#define png_debug2(l,m,p1,p2) \
2372
fprintf(PNG_DEBUG_FILE,"%s"m,(num_tabs==1 ? "\t" : \
2373
(num_tabs==2 ? "\t\t":(num_tabs>2 ? "\t\t\t":""))),p1,p2); \
2375
#endif /* (PNG_DEBUG > 1) */
2376
#endif /* _MSC_VER */
2377
#endif /* (PNG_DEBUG > 0) */
2378
#endif /* PNG_DEBUG */
2380
#define png_debug(l, m)
2383
#define png_debug1(l, m, p1)
2386
#define png_debug2(l, m, p1, p2)
2389
extern PNG_EXPORT(png_bytep,png_sig_bytes) PNGARG((void));
2391
extern PNG_EXPORT(png_charp,png_get_copyright) PNGARG((png_structp png_ptr));
2392
extern PNG_EXPORT(png_charp,png_get_header_ver) PNGARG((png_structp png_ptr));
2393
extern PNG_EXPORT(png_charp,png_get_header_version) PNGARG((png_structp png_ptr));
2394
extern PNG_EXPORT(png_charp,png_get_libpng_ver) PNGARG((png_structp png_ptr));
2396
#ifdef PNG_MNG_FEATURES_SUPPORTED
2397
extern PNG_EXPORT(png_uint_32,png_permit_mng_features) PNGARG((png_structp
2398
png_ptr, png_uint_32 mng_features_permitted));
2401
/* For use in png_set_keep_unknown, added to version 1.2.6 */
2402
#define PNG_HANDLE_CHUNK_AS_DEFAULT 0
2403
#define PNG_HANDLE_CHUNK_NEVER 1
2404
#define PNG_HANDLE_CHUNK_IF_SAFE 2
2405
#define PNG_HANDLE_CHUNK_ALWAYS 3
2407
/* Added to version 1.2.0 */
2408
#if defined(PNG_ASSEMBLER_CODE_SUPPORTED)
2409
#define PNG_ASM_FLAG_MMX_SUPPORT_COMPILED 0x01 /* not user-settable */
2410
#define PNG_ASM_FLAG_MMX_SUPPORT_IN_CPU 0x02 /* not user-settable */
2411
#define PNG_ASM_FLAG_MMX_READ_COMBINE_ROW 0x04
2412
#define PNG_ASM_FLAG_MMX_READ_INTERLACE 0x08
2413
#define PNG_ASM_FLAG_MMX_READ_FILTER_SUB 0x10
2414
#define PNG_ASM_FLAG_MMX_READ_FILTER_UP 0x20
2415
#define PNG_ASM_FLAG_MMX_READ_FILTER_AVG 0x40
2416
#define PNG_ASM_FLAG_MMX_READ_FILTER_PAETH 0x80
2417
#define PNG_ASM_FLAGS_INITIALIZED 0x80000000 /* not user-settable */
2419
#define PNG_MMX_READ_FLAGS ( PNG_ASM_FLAG_MMX_READ_COMBINE_ROW \
2420
| PNG_ASM_FLAG_MMX_READ_INTERLACE \
2421
| PNG_ASM_FLAG_MMX_READ_FILTER_SUB \
2422
| PNG_ASM_FLAG_MMX_READ_FILTER_UP \
2423
| PNG_ASM_FLAG_MMX_READ_FILTER_AVG \
2424
| PNG_ASM_FLAG_MMX_READ_FILTER_PAETH )
2425
#define PNG_MMX_WRITE_FLAGS ( 0 )
2427
#define PNG_MMX_FLAGS ( PNG_ASM_FLAG_MMX_SUPPORT_COMPILED \
2428
| PNG_ASM_FLAG_MMX_SUPPORT_IN_CPU \
2429
| PNG_MMX_READ_FLAGS \
2430
| PNG_MMX_WRITE_FLAGS )
2432
#define PNG_SELECT_READ 1
2433
#define PNG_SELECT_WRITE 2
2435
#if !defined(PNG_1_0_X)
2437
extern PNG_EXPORT(png_uint_32,png_get_mmx_flagmask)
2438
PNGARG((int flag_select, int *compilerID));
2441
extern PNG_EXPORT(png_uint_32,png_get_asm_flagmask)
2442
PNGARG((int flag_select));
2445
extern PNG_EXPORT(png_uint_32,png_get_asm_flags)
2446
PNGARG((png_structp png_ptr));
2449
extern PNG_EXPORT(png_byte,png_get_mmx_bitdepth_threshold)
2450
PNGARG((png_structp png_ptr));
2453
extern PNG_EXPORT(png_uint_32,png_get_mmx_rowbytes_threshold)
2454
PNGARG((png_structp png_ptr));
2457
extern PNG_EXPORT(void,png_set_asm_flags)
2458
PNGARG((png_structp png_ptr, png_uint_32 asm_flags));
2461
extern PNG_EXPORT(void,png_set_mmx_thresholds)
2462
PNGARG((png_structp png_ptr, png_byte mmx_bitdepth_threshold,
2463
png_uint_32 mmx_rowbytes_threshold));
2465
#endif /* PNG_1_0_X */
2466
#endif /* PNG_ASSEMBLER_CODE_SUPPORTED */
2468
#if !defined(PNG_1_0_X)
2469
/* png.c, pnggccrd.c, or pngvcrd.c */
2470
extern PNG_EXPORT(int,png_mmx_support) PNGARG((void));
2472
/* Strip the prepended error numbers ("#nnn ") from error and warning
2473
* messages before passing them to the error or warning handler. */
2474
#ifdef PNG_ERROR_NUMBERS_SUPPORTED
2475
extern PNG_EXPORT(void,png_set_strip_error_numbers) PNGARG((png_structp
2476
png_ptr, png_uint_32 strip_mode));
2479
#endif /* PNG_1_0_X */
2481
/* Added at libpng-1.2.6 */
2482
#ifdef PNG_SET_USER_LIMITS_SUPPORTED
2483
extern PNG_EXPORT(void,png_set_user_limits) PNGARG((png_structp
2484
png_ptr, png_uint_32 user_width_max, png_uint_32 user_height_max));
2485
extern PNG_EXPORT(png_uint_32,png_get_user_width_max) PNGARG((png_structp
2487
extern PNG_EXPORT(png_uint_32,png_get_user_height_max) PNGARG((png_structp
2491
/* Maintainer: Put new public prototypes here ^, in libpng.3, and project defs */
2493
#ifdef PNG_READ_COMPOSITE_NODIV_SUPPORTED
2494
/* With these routines we avoid an integer divide, which will be slower on
2495
* most machines. However, it does take more operations than the corresponding
2496
* divide method, so it may be slower on a few RISC systems. There are two
2497
* shifts (by 8 or 16 bits) and an addition, versus a single integer divide.
2499
* Note that the rounding factors are NOT supposed to be the same! 128 and
2500
* 32768 are correct for the NODIV code; 127 and 32767 are correct for the
2503
* [Optimized code by Greg Roelofs and Mark Adler...blame us for bugs. :-) ]
2506
/* fg and bg should be in `gamma 1.0' space; alpha is the opacity */
2508
# define png_composite(composite, fg, alpha, bg) \
2509
{ png_uint_16 temp = (png_uint_16)((png_uint_16)(fg) * (png_uint_16)(alpha) \
2510
+ (png_uint_16)(bg)*(png_uint_16)(255 - \
2511
(png_uint_16)(alpha)) + (png_uint_16)128); \
2512
(composite) = (png_byte)((temp + (temp >> 8)) >> 8); }
2514
# define png_composite_16(composite, fg, alpha, bg) \
2515
{ png_uint_32 temp = (png_uint_32)((png_uint_32)(fg) * (png_uint_32)(alpha) \
2516
+ (png_uint_32)(bg)*(png_uint_32)(65535L - \
2517
(png_uint_32)(alpha)) + (png_uint_32)32768L); \
2518
(composite) = (png_uint_16)((temp + (temp >> 16)) >> 16); }
2520
#else /* standard method using integer division */
2522
# define png_composite(composite, fg, alpha, bg) \
2523
(composite) = (png_byte)(((png_uint_16)(fg) * (png_uint_16)(alpha) + \
2524
(png_uint_16)(bg) * (png_uint_16)(255 - (png_uint_16)(alpha)) + \
2525
(png_uint_16)127) / 255)
2527
# define png_composite_16(composite, fg, alpha, bg) \
2528
(composite) = (png_uint_16)(((png_uint_32)(fg) * (png_uint_32)(alpha) + \
2529
(png_uint_32)(bg)*(png_uint_32)(65535L - (png_uint_32)(alpha)) + \
2530
(png_uint_32)32767) / (png_uint_32)65535L)
2532
#endif /* PNG_READ_COMPOSITE_NODIV_SUPPORTED */
2534
/* These next functions are used internally in the code. They generally
2535
* shouldn't be used unless you are writing code to add or replace some
2536
* functionality in libpng. More information about most functions can
2537
* be found in the files where the functions are located.
2540
#if defined(PNG_INTERNAL)
2542
/* Various modes of operation. Note that after an init, mode is set to
2543
* zero automatically when the structure is created.
2545
#define PNG_HAVE_IHDR 0x01
2546
#define PNG_HAVE_PLTE 0x02
2547
#define PNG_HAVE_IDAT 0x04
2548
#define PNG_AFTER_IDAT 0x08
2549
#define PNG_HAVE_IEND 0x10
2550
#define PNG_HAVE_gAMA 0x20
2551
#define PNG_HAVE_cHRM 0x40
2552
#define PNG_HAVE_sRGB 0x80
2553
#define PNG_HAVE_CHUNK_HEADER 0x100
2554
#define PNG_WROTE_tIME 0x200
2555
#define PNG_WROTE_INFO_BEFORE_PLTE 0x400
2556
#define PNG_BACKGROUND_IS_GRAY 0x800
2557
#define PNG_HAVE_PNG_SIGNATURE 0x1000
2559
/* flags for the transformations the PNG library does on the image data */
2560
#define PNG_BGR 0x0001
2561
#define PNG_INTERLACE 0x0002
2562
#define PNG_PACK 0x0004
2563
#define PNG_SHIFT 0x0008
2564
#define PNG_SWAP_BYTES 0x0010
2565
#define PNG_INVERT_MONO 0x0020
2566
#define PNG_DITHER 0x0040
2567
#define PNG_BACKGROUND 0x0080
2568
#define PNG_BACKGROUND_EXPAND 0x0100
2570
#define PNG_16_TO_8 0x0400
2571
#define PNG_RGBA 0x0800
2572
#define PNG_EXPAND 0x1000
2573
#define PNG_GAMMA 0x2000
2574
#define PNG_GRAY_TO_RGB 0x4000
2575
#define PNG_FILLER 0x8000L
2576
#define PNG_PACKSWAP 0x10000L
2577
#define PNG_SWAP_ALPHA 0x20000L
2578
#define PNG_STRIP_ALPHA 0x40000L
2579
#define PNG_INVERT_ALPHA 0x80000L
2580
#define PNG_USER_TRANSFORM 0x100000L
2581
#define PNG_RGB_TO_GRAY_ERR 0x200000L
2582
#define PNG_RGB_TO_GRAY_WARN 0x400000L
2583
#define PNG_RGB_TO_GRAY 0x600000L /* two bits, RGB_TO_GRAY_ERR|WARN */
2584
#define PNG_ADD_ALPHA 0x1000000L /* Added to libpng-1.2.7 */
2586
/* flags for png_create_struct */
2587
#define PNG_STRUCT_PNG 0x0001
2588
#define PNG_STRUCT_INFO 0x0002
2590
/* Scaling factor for filter heuristic weighting calculations */
2591
#define PNG_WEIGHT_SHIFT 8
2592
#define PNG_WEIGHT_FACTOR (1<<(PNG_WEIGHT_SHIFT))
2593
#define PNG_COST_SHIFT 3
2594
#define PNG_COST_FACTOR (1<<(PNG_COST_SHIFT))
2596
/* flags for the png_ptr->flags rather than declaring a byte for each one */
2597
#define PNG_FLAG_ZLIB_CUSTOM_STRATEGY 0x0001
2598
#define PNG_FLAG_ZLIB_CUSTOM_LEVEL 0x0002
2599
#define PNG_FLAG_ZLIB_CUSTOM_MEM_LEVEL 0x0004
2600
#define PNG_FLAG_ZLIB_CUSTOM_WINDOW_BITS 0x0008
2601
#define PNG_FLAG_ZLIB_CUSTOM_METHOD 0x0010
2602
#define PNG_FLAG_ZLIB_FINISHED 0x0020
2603
#define PNG_FLAG_ROW_INIT 0x0040
2604
#define PNG_FLAG_FILLER_AFTER 0x0080
2605
#define PNG_FLAG_CRC_ANCILLARY_USE 0x0100
2606
#define PNG_FLAG_CRC_ANCILLARY_NOWARN 0x0200
2607
#define PNG_FLAG_CRC_CRITICAL_USE 0x0400
2608
#define PNG_FLAG_CRC_CRITICAL_IGNORE 0x0800
2609
#define PNG_FLAG_FREE_PLTE 0x1000
2610
#define PNG_FLAG_FREE_TRNS 0x2000
2611
#define PNG_FLAG_FREE_HIST 0x4000
2612
#define PNG_FLAG_KEEP_UNKNOWN_CHUNKS 0x8000L
2613
#define PNG_FLAG_KEEP_UNSAFE_CHUNKS 0x10000L
2614
#define PNG_FLAG_LIBRARY_MISMATCH 0x20000L
2615
#define PNG_FLAG_STRIP_ERROR_NUMBERS 0x40000L
2616
#define PNG_FLAG_STRIP_ERROR_TEXT 0x80000L
2617
#define PNG_FLAG_MALLOC_NULL_MEM_OK 0x100000L
2619
#define PNG_FLAG_CRC_ANCILLARY_MASK (PNG_FLAG_CRC_ANCILLARY_USE | \
2620
PNG_FLAG_CRC_ANCILLARY_NOWARN)
2622
#define PNG_FLAG_CRC_CRITICAL_MASK (PNG_FLAG_CRC_CRITICAL_USE | \
2623
PNG_FLAG_CRC_CRITICAL_IGNORE)
2625
#define PNG_FLAG_CRC_MASK (PNG_FLAG_CRC_ANCILLARY_MASK | \
2626
PNG_FLAG_CRC_CRITICAL_MASK)
2628
/* save typing and make code easier to understand */
2630
#define PNG_COLOR_DIST(c1, c2) (abs((int)((c1).red) - (int)((c2).red)) + \
2631
abs((int)((c1).green) - (int)((c2).green)) + \
2632
abs((int)((c1).blue) - (int)((c2).blue)))
2634
/* Added to libpng-1.2.6 JB */
2635
#define PNG_ROWBYTES(pixel_bits, width) \
2636
((pixel_bits) >= 8 ? \
2637
((width) * (((png_uint_32)(pixel_bits)) >> 3)) : \
2638
(( ((width) * ((png_uint_32)(pixel_bits))) + 7) >> 3) )
2640
/* PNG_OUT_OF_RANGE returns true if value is outside the range
2641
ideal-delta..ideal+delta. Each argument is evaluated twice.
2642
"ideal" and "delta" should be constants, normally simple
2643
integers, "value" a variable. Added to libpng-1.2.6 JB */
2644
#define PNG_OUT_OF_RANGE(value, ideal, delta) \
2645
( (value) < (ideal)-(delta) || (value) > (ideal)+(delta) )
2647
/* variables declared in png.c - only it needs to define PNG_NO_EXTERN */
2648
#if !defined(PNG_NO_EXTERN) || defined(PNG_ALWAYS_EXTERN)
2649
/* place to hold the signature string for a PNG file. */
2650
#ifdef PNG_USE_GLOBAL_ARRAYS
2651
PNG_EXPORT_VAR (const png_byte FARDATA) png_sig[8];
2653
#define png_sig png_sig_bytes(NULL)
2655
#endif /* PNG_NO_EXTERN */
2657
/* Constant strings for known chunk types. If you need to add a chunk,
2658
* define the name here, and add an invocation of the macro in png.c and
2659
* wherever it's needed.
2661
#define PNG_IHDR const png_byte png_IHDR[5] = { 73, 72, 68, 82, '\0'}
2662
#define PNG_IDAT const png_byte png_IDAT[5] = { 73, 68, 65, 84, '\0'}
2663
#define PNG_IEND const png_byte png_IEND[5] = { 73, 69, 78, 68, '\0'}
2664
#define PNG_PLTE const png_byte png_PLTE[5] = { 80, 76, 84, 69, '\0'}
2665
#define PNG_bKGD const png_byte png_bKGD[5] = { 98, 75, 71, 68, '\0'}
2666
#define PNG_cHRM const png_byte png_cHRM[5] = { 99, 72, 82, 77, '\0'}
2667
#define PNG_gAMA const png_byte png_gAMA[5] = {103, 65, 77, 65, '\0'}
2668
#define PNG_hIST const png_byte png_hIST[5] = {104, 73, 83, 84, '\0'}
2669
#define PNG_iCCP const png_byte png_iCCP[5] = {105, 67, 67, 80, '\0'}
2670
#define PNG_iTXt const png_byte png_iTXt[5] = {105, 84, 88, 116, '\0'}
2671
#define PNG_oFFs const png_byte png_oFFs[5] = {111, 70, 70, 115, '\0'}
2672
#define PNG_pCAL const png_byte png_pCAL[5] = {112, 67, 65, 76, '\0'}
2673
#define PNG_sCAL const png_byte png_sCAL[5] = {115, 67, 65, 76, '\0'}
2674
#define PNG_pHYs const png_byte png_pHYs[5] = {112, 72, 89, 115, '\0'}
2675
#define PNG_sBIT const png_byte png_sBIT[5] = {115, 66, 73, 84, '\0'}
2676
#define PNG_sPLT const png_byte png_sPLT[5] = {115, 80, 76, 84, '\0'}
2677
#define PNG_sRGB const png_byte png_sRGB[5] = {115, 82, 71, 66, '\0'}
2678
#define PNG_tEXt const png_byte png_tEXt[5] = {116, 69, 88, 116, '\0'}
2679
#define PNG_tIME const png_byte png_tIME[5] = {116, 73, 77, 69, '\0'}
2680
#define PNG_tRNS const png_byte png_tRNS[5] = {116, 82, 78, 83, '\0'}
2681
#define PNG_zTXt const png_byte png_zTXt[5] = {122, 84, 88, 116, '\0'}
2683
#ifdef PNG_USE_GLOBAL_ARRAYS
2684
PNG_EXPORT_VAR (const png_byte FARDATA) png_IHDR[5];
2685
PNG_EXPORT_VAR (const png_byte FARDATA) png_IDAT[5];
2686
PNG_EXPORT_VAR (const png_byte FARDATA) png_IEND[5];
2687
PNG_EXPORT_VAR (const png_byte FARDATA) png_PLTE[5];
2688
PNG_EXPORT_VAR (const png_byte FARDATA) png_bKGD[5];
2689
PNG_EXPORT_VAR (const png_byte FARDATA) png_cHRM[5];
2690
PNG_EXPORT_VAR (const png_byte FARDATA) png_gAMA[5];
2691
PNG_EXPORT_VAR (const png_byte FARDATA) png_hIST[5];
2692
PNG_EXPORT_VAR (const png_byte FARDATA) png_iCCP[5];
2693
PNG_EXPORT_VAR (const png_byte FARDATA) png_iTXt[5];
2694
PNG_EXPORT_VAR (const png_byte FARDATA) png_oFFs[5];
2695
PNG_EXPORT_VAR (const png_byte FARDATA) png_pCAL[5];
2696
PNG_EXPORT_VAR (const png_byte FARDATA) png_sCAL[5];
2697
PNG_EXPORT_VAR (const png_byte FARDATA) png_pHYs[5];
2698
PNG_EXPORT_VAR (const png_byte FARDATA) png_sBIT[5];
2699
PNG_EXPORT_VAR (const png_byte FARDATA) png_sPLT[5];
2700
PNG_EXPORT_VAR (const png_byte FARDATA) png_sRGB[5];
2701
PNG_EXPORT_VAR (const png_byte FARDATA) png_tEXt[5];
2702
PNG_EXPORT_VAR (const png_byte FARDATA) png_tIME[5];
2703
PNG_EXPORT_VAR (const png_byte FARDATA) png_tRNS[5];
2704
PNG_EXPORT_VAR (const png_byte FARDATA) png_zTXt[5];
2705
#endif /* PNG_USE_GLOBAL_ARRAYS */
2708
/* Inline macros to do direct reads of bytes from the input buffer. These
2709
* require that you are using an architecture that uses PNG byte ordering
2710
* (MSB first) and supports unaligned data storage. I think that PowerPC
2711
* in big-endian mode and 680x0 are the only ones that will support this.
2712
* The x86 line of processors definitely do not. The png_get_int_32()
2713
* routine also assumes we are using two's complement format for negative
2714
* values, which is almost certainly true.
2716
#if defined(PNG_READ_BIG_ENDIAN_SUPPORTED)
2717
# if defined(PNG_pCAL_SUPPORTED) || defined(PNG_oFFs_SUPPORTED)
2718
# define png_get_int_32(buf) ( *((png_int_32p) (buf)))
2720
# define png_get_uint_32(buf) ( *((png_uint_32p) (buf)))
2721
# define png_get_uint_16(buf) ( *((png_uint_16p) (buf)))
2723
# if defined(PNG_pCAL_SUPPORTED) || defined(PNG_oFFs_SUPPORTED)
2724
PNG_EXTERN png_int_32 png_get_int_32 PNGARG((png_bytep buf));
2726
PNG_EXTERN png_uint_32 png_get_uint_32 PNGARG((png_bytep buf));
2727
PNG_EXTERN png_uint_16 png_get_uint_16 PNGARG((png_bytep buf));
2728
#endif /* !PNG_READ_BIG_ENDIAN_SUPPORTED */
2729
PNG_EXTERN png_uint_32 png_get_uint_31 PNGARG((png_structp png_ptr,
2732
/* Initialize png_ptr struct for reading, and allocate any other memory.
2733
* (old interface - DEPRECATED - use png_create_read_struct instead).
2735
extern PNG_EXPORT(void,png_read_init) PNGARG((png_structp png_ptr));
2736
#undef png_read_init
2737
#define png_read_init(png_ptr) png_read_init_3(&png_ptr, \
2738
PNG_LIBPNG_VER_STRING, png_sizeof(png_struct));
2739
extern PNG_EXPORT(void,png_read_init_3) PNGARG((png_structpp ptr_ptr,
2740
png_const_charp user_png_ver, png_size_t png_struct_size));
2741
extern PNG_EXPORT(void,png_read_init_2) PNGARG((png_structp png_ptr,
2742
png_const_charp user_png_ver, png_size_t png_struct_size, png_size_t
2745
/* Initialize png_ptr struct for writing, and allocate any other memory.
2746
* (old interface - DEPRECATED - use png_create_write_struct instead).
2748
extern PNG_EXPORT(void,png_write_init) PNGARG((png_structp png_ptr));
2749
#undef png_write_init
2750
#define png_write_init(png_ptr) png_write_init_3(&png_ptr, \
2751
PNG_LIBPNG_VER_STRING, png_sizeof(png_struct));
2752
extern PNG_EXPORT(void,png_write_init_3) PNGARG((png_structpp ptr_ptr,
2753
png_const_charp user_png_ver, png_size_t png_struct_size));
2754
extern PNG_EXPORT(void,png_write_init_2) PNGARG((png_structp png_ptr,
2755
png_const_charp user_png_ver, png_size_t png_struct_size, png_size_t
2758
/* Allocate memory for an internal libpng struct */
2759
PNG_EXTERN png_voidp png_create_struct PNGARG((int type));
2761
/* Free memory from internal libpng struct */
2762
PNG_EXTERN void png_destroy_struct PNGARG((png_voidp struct_ptr));
2764
PNG_EXTERN png_voidp png_create_struct_2 PNGARG((int type, png_malloc_ptr
2765
malloc_fn, png_voidp mem_ptr));
2766
PNG_EXTERN void png_destroy_struct_2 PNGARG((png_voidp struct_ptr,
2767
png_free_ptr free_fn, png_voidp mem_ptr));
2769
/* Free any memory that info_ptr points to and reset struct. */
2770
PNG_EXTERN void png_info_destroy PNGARG((png_structp png_ptr,
2771
png_infop info_ptr));
2774
/* Function to allocate memory for zlib. */
2775
PNG_EXTERN voidpf png_zalloc PNGARG((voidpf png_ptr, uInt items, uInt size));
2777
/* Function to free memory for zlib */
2778
PNG_EXTERN void png_zfree PNGARG((voidpf png_ptr, voidpf ptr));
2781
/* Function to convert a sizeof an item to png_sizeof item */
2782
PNG_EXTERN png_size_t PNGAPI png_convert_size PNGARG((size_t size));
2785
/* Next four functions are used internally as callbacks. PNGAPI is required
2786
* but not PNG_EXPORT. PNGAPI added at libpng version 1.2.3. */
2788
PNG_EXTERN void PNGAPI png_default_read_data PNGARG((png_structp png_ptr,
2789
png_bytep data, png_size_t length));
2791
#ifdef PNG_PROGRESSIVE_READ_SUPPORTED
2792
PNG_EXTERN void PNGAPI png_push_fill_buffer PNGARG((png_structp png_ptr,
2793
png_bytep buffer, png_size_t length));
2796
PNG_EXTERN void PNGAPI png_default_write_data PNGARG((png_structp png_ptr,
2797
png_bytep data, png_size_t length));
2799
#if defined(PNG_WRITE_FLUSH_SUPPORTED)
2800
#if !defined(PNG_NO_STDIO)
2801
PNG_EXTERN void PNGAPI png_default_flush PNGARG((png_structp png_ptr));
2804
#else /* PNG_1_0_X */
2805
#ifdef PNG_PROGRESSIVE_READ_SUPPORTED
2806
PNG_EXTERN void png_push_fill_buffer PNGARG((png_structp png_ptr,
2807
png_bytep buffer, png_size_t length));
2809
#endif /* PNG_1_0_X */
2811
/* Reset the CRC variable */
2812
PNG_EXTERN void png_reset_crc PNGARG((png_structp png_ptr));
2814
/* Write the "data" buffer to whatever output you are using. */
2815
PNG_EXTERN void png_write_data PNGARG((png_structp png_ptr, png_bytep data,
2816
png_size_t length));
2818
/* Read data from whatever input you are using into the "data" buffer */
2819
PNG_EXTERN void png_read_data PNGARG((png_structp png_ptr, png_bytep data,
2820
png_size_t length));
2822
/* Read bytes into buf, and update png_ptr->crc */
2823
PNG_EXTERN void png_crc_read PNGARG((png_structp png_ptr, png_bytep buf,
2824
png_size_t length));
2826
/* Decompress data in a chunk that uses compression */
2827
#if defined(PNG_zTXt_SUPPORTED) || defined(PNG_iTXt_SUPPORTED) || \
2828
defined(PNG_iCCP_SUPPORTED) || defined(PNG_sPLT_SUPPORTED)
2829
PNG_EXTERN png_charp png_decompress_chunk PNGARG((png_structp png_ptr,
2830
int comp_type, png_charp chunkdata, png_size_t chunklength,
2831
png_size_t prefix_length, png_size_t *data_length));
2834
/* Read "skip" bytes, read the file crc, and (optionally) verify png_ptr->crc */
2835
PNG_EXTERN int png_crc_finish PNGARG((png_structp png_ptr, png_uint_32 skip));
2837
/* Read the CRC from the file and compare it to the libpng calculated CRC */
2838
PNG_EXTERN int png_crc_error PNGARG((png_structp png_ptr));
2840
/* Calculate the CRC over a section of data. Note that we are only
2841
* passing a maximum of 64K on systems that have this as a memory limit,
2842
* since this is the maximum buffer size we can specify.
2844
PNG_EXTERN void png_calculate_crc PNGARG((png_structp png_ptr, png_bytep ptr,
2845
png_size_t length));
2847
#if defined(PNG_WRITE_FLUSH_SUPPORTED)
2848
PNG_EXTERN void png_flush PNGARG((png_structp png_ptr));
2852
/* Place a 32-bit number into a buffer in PNG byte order (big-endian).
2853
* The only currently known PNG chunks that use signed numbers are
2854
* the ancillary extension chunks, oFFs and pCAL.
2856
PNG_EXTERN void png_save_uint_32 PNGARG((png_bytep buf, png_uint_32 i));
2858
#if defined(PNG_WRITE_pCAL_SUPPORTED) || defined(PNG_WRITE_oFFs_SUPPORTED)
2859
PNG_EXTERN void png_save_int_32 PNGARG((png_bytep buf, png_int_32 i));
2862
/* Place a 16-bit number into a buffer in PNG byte order.
2863
* The parameter is declared unsigned int, not png_uint_16,
2864
* just to avoid potential problems on pre-ANSI C compilers.
2866
PNG_EXTERN void png_save_uint_16 PNGARG((png_bytep buf, unsigned int i));
2868
/* simple function to write the signature */
2869
PNG_EXTERN void png_write_sig PNGARG((png_structp png_ptr));
2871
/* write various chunks */
2873
/* Write the IHDR chunk, and update the png_struct with the necessary
2876
PNG_EXTERN void png_write_IHDR PNGARG((png_structp png_ptr, png_uint_32 width,
2878
int bit_depth, int color_type, int compression_method, int filter_method,
2879
int interlace_method));
2881
PNG_EXTERN void png_write_PLTE PNGARG((png_structp png_ptr, png_colorp palette,
2882
png_uint_32 num_pal));
2884
PNG_EXTERN void png_write_IDAT PNGARG((png_structp png_ptr, png_bytep data,
2885
png_size_t length));
2887
PNG_EXTERN void png_write_IEND PNGARG((png_structp png_ptr));
2889
#if defined(PNG_WRITE_gAMA_SUPPORTED)
2890
#ifdef PNG_FLOATING_POINT_SUPPORTED
2891
PNG_EXTERN void png_write_gAMA PNGARG((png_structp png_ptr, double file_gamma));
2893
#ifdef PNG_FIXED_POINT_SUPPORTED
2894
PNG_EXTERN void png_write_gAMA_fixed PNGARG((png_structp png_ptr, png_fixed_point
2899
#if defined(PNG_WRITE_sBIT_SUPPORTED)
2900
PNG_EXTERN void png_write_sBIT PNGARG((png_structp png_ptr, png_color_8p sbit,
2904
#if defined(PNG_WRITE_cHRM_SUPPORTED)
2905
#ifdef PNG_FLOATING_POINT_SUPPORTED
2906
PNG_EXTERN void png_write_cHRM PNGARG((png_structp png_ptr,
2907
double white_x, double white_y,
2908
double red_x, double red_y, double green_x, double green_y,
2909
double blue_x, double blue_y));
2911
#ifdef PNG_FIXED_POINT_SUPPORTED
2912
PNG_EXTERN void png_write_cHRM_fixed PNGARG((png_structp png_ptr,
2913
png_fixed_point int_white_x, png_fixed_point int_white_y,
2914
png_fixed_point int_red_x, png_fixed_point int_red_y, png_fixed_point
2915
int_green_x, png_fixed_point int_green_y, png_fixed_point int_blue_x,
2916
png_fixed_point int_blue_y));
2920
#if defined(PNG_WRITE_sRGB_SUPPORTED)
2921
PNG_EXTERN void png_write_sRGB PNGARG((png_structp png_ptr,
2925
#if defined(PNG_WRITE_iCCP_SUPPORTED)
2926
PNG_EXTERN void png_write_iCCP PNGARG((png_structp png_ptr,
2927
png_charp name, int compression_type,
2928
png_charp profile, int proflen));
2929
/* Note to maintainer: profile should be png_bytep */
2932
#if defined(PNG_WRITE_sPLT_SUPPORTED)
2933
PNG_EXTERN void png_write_sPLT PNGARG((png_structp png_ptr,
2934
png_sPLT_tp palette));
2937
#if defined(PNG_WRITE_tRNS_SUPPORTED)
2938
PNG_EXTERN void png_write_tRNS PNGARG((png_structp png_ptr, png_bytep trans,
2939
png_color_16p values, int number, int color_type));
2942
#if defined(PNG_WRITE_bKGD_SUPPORTED)
2943
PNG_EXTERN void png_write_bKGD PNGARG((png_structp png_ptr,
2944
png_color_16p values, int color_type));
2947
#if defined(PNG_WRITE_hIST_SUPPORTED)
2948
PNG_EXTERN void png_write_hIST PNGARG((png_structp png_ptr, png_uint_16p hist,
2952
#if defined(PNG_WRITE_TEXT_SUPPORTED) || defined(PNG_WRITE_pCAL_SUPPORTED) || \
2953
defined(PNG_WRITE_iCCP_SUPPORTED) || defined(PNG_WRITE_sPLT_SUPPORTED)
2954
PNG_EXTERN png_size_t png_check_keyword PNGARG((png_structp png_ptr,
2955
png_charp key, png_charpp new_key));
2958
#if defined(PNG_WRITE_tEXt_SUPPORTED)
2959
PNG_EXTERN void png_write_tEXt PNGARG((png_structp png_ptr, png_charp key,
2960
png_charp text, png_size_t text_len));
2963
#if defined(PNG_WRITE_zTXt_SUPPORTED)
2964
PNG_EXTERN void png_write_zTXt PNGARG((png_structp png_ptr, png_charp key,
2965
png_charp text, png_size_t text_len, int compression));
2968
#if defined(PNG_WRITE_iTXt_SUPPORTED)
2969
PNG_EXTERN void png_write_iTXt PNGARG((png_structp png_ptr,
2970
int compression, png_charp key, png_charp lang, png_charp lang_key,
2974
#if defined(PNG_TEXT_SUPPORTED) /* Added at version 1.0.14 and 1.2.4 */
2975
PNG_EXTERN int png_set_text_2 PNGARG((png_structp png_ptr,
2976
png_infop info_ptr, png_textp text_ptr, int num_text));
2979
#if defined(PNG_WRITE_oFFs_SUPPORTED)
2980
PNG_EXTERN void png_write_oFFs PNGARG((png_structp png_ptr,
2981
png_int_32 x_offset, png_int_32 y_offset, int unit_type));
2984
#if defined(PNG_WRITE_pCAL_SUPPORTED)
2985
PNG_EXTERN void png_write_pCAL PNGARG((png_structp png_ptr, png_charp purpose,
2986
png_int_32 X0, png_int_32 X1, int type, int nparams,
2987
png_charp units, png_charpp params));
2990
#if defined(PNG_WRITE_pHYs_SUPPORTED)
2991
PNG_EXTERN void png_write_pHYs PNGARG((png_structp png_ptr,
2992
png_uint_32 x_pixels_per_unit, png_uint_32 y_pixels_per_unit,
2996
#if defined(PNG_WRITE_tIME_SUPPORTED)
2997
PNG_EXTERN void png_write_tIME PNGARG((png_structp png_ptr,
2998
png_timep mod_time));
3001
#if defined(PNG_WRITE_sCAL_SUPPORTED)
3002
#if defined(PNG_FLOATING_POINT_SUPPORTED) && !defined(PNG_NO_STDIO)
3003
PNG_EXTERN void png_write_sCAL PNGARG((png_structp png_ptr,
3004
int unit, double width, double height));
3006
#ifdef PNG_FIXED_POINT_SUPPORTED
3007
PNG_EXTERN void png_write_sCAL_s PNGARG((png_structp png_ptr,
3008
int unit, png_charp width, png_charp height));
3013
/* Called when finished processing a row of data */
3014
PNG_EXTERN void png_write_finish_row PNGARG((png_structp png_ptr));
3016
/* Internal use only. Called before first row of data */
3017
PNG_EXTERN void png_write_start_row PNGARG((png_structp png_ptr));
3019
#if defined(PNG_READ_GAMMA_SUPPORTED)
3020
PNG_EXTERN void png_build_gamma_table PNGARG((png_structp png_ptr));
3023
/* combine a row of data, dealing with alpha, etc. if requested */
3024
PNG_EXTERN void png_combine_row PNGARG((png_structp png_ptr, png_bytep row,
3027
#if defined(PNG_READ_INTERLACING_SUPPORTED)
3028
/* expand an interlaced row */
3029
/* OLD pre-1.0.9 interface:
3030
PNG_EXTERN void png_do_read_interlace PNGARG((png_row_infop row_info,
3031
png_bytep row, int pass, png_uint_32 transformations));
3033
PNG_EXTERN void png_do_read_interlace PNGARG((png_structp png_ptr));
3036
/* GRR TO DO (2.0 or whenever): simplify other internal calling interfaces */
3038
#if defined(PNG_WRITE_INTERLACING_SUPPORTED)
3039
/* grab pixels out of a row for an interlaced pass */
3040
PNG_EXTERN void png_do_write_interlace PNGARG((png_row_infop row_info,
3041
png_bytep row, int pass));
3044
/* unfilter a row */
3045
PNG_EXTERN void png_read_filter_row PNGARG((png_structp png_ptr,
3046
png_row_infop row_info, png_bytep row, png_bytep prev_row, int filter));
3048
/* Choose the best filter to use and filter the row data */
3049
PNG_EXTERN void png_write_find_filter PNGARG((png_structp png_ptr,
3050
png_row_infop row_info));
3052
/* Write out the filtered row. */
3053
PNG_EXTERN void png_write_filtered_row PNGARG((png_structp png_ptr,
3054
png_bytep filtered_row));
3055
/* finish a row while reading, dealing with interlacing passes, etc. */
3056
PNG_EXTERN void png_read_finish_row PNGARG((png_structp png_ptr));
3058
/* initialize the row buffers, etc. */
3059
PNG_EXTERN void png_read_start_row PNGARG((png_structp png_ptr));
3060
/* optional call to update the users info structure */
3061
PNG_EXTERN void png_read_transform_info PNGARG((png_structp png_ptr,
3062
png_infop info_ptr));
3064
/* these are the functions that do the transformations */
3065
#if defined(PNG_READ_FILLER_SUPPORTED)
3066
PNG_EXTERN void png_do_read_filler PNGARG((png_row_infop row_info,
3067
png_bytep row, png_uint_32 filler, png_uint_32 flags));
3070
#if defined(PNG_READ_SWAP_ALPHA_SUPPORTED)
3071
PNG_EXTERN void png_do_read_swap_alpha PNGARG((png_row_infop row_info,
3075
#if defined(PNG_WRITE_SWAP_ALPHA_SUPPORTED)
3076
PNG_EXTERN void png_do_write_swap_alpha PNGARG((png_row_infop row_info,
3080
#if defined(PNG_READ_INVERT_ALPHA_SUPPORTED)
3081
PNG_EXTERN void png_do_read_invert_alpha PNGARG((png_row_infop row_info,
3085
#if defined(PNG_WRITE_INVERT_ALPHA_SUPPORTED)
3086
PNG_EXTERN void png_do_write_invert_alpha PNGARG((png_row_infop row_info,
3090
#if defined(PNG_WRITE_FILLER_SUPPORTED) || \
3091
defined(PNG_READ_STRIP_ALPHA_SUPPORTED)
3092
PNG_EXTERN void png_do_strip_filler PNGARG((png_row_infop row_info,
3093
png_bytep row, png_uint_32 flags));
3096
#if defined(PNG_READ_SWAP_SUPPORTED) || defined(PNG_WRITE_SWAP_SUPPORTED)
3097
PNG_EXTERN void png_do_swap PNGARG((png_row_infop row_info, png_bytep row));
3100
#if defined(PNG_READ_PACKSWAP_SUPPORTED) || defined(PNG_WRITE_PACKSWAP_SUPPORTED)
3101
PNG_EXTERN void png_do_packswap PNGARG((png_row_infop row_info, png_bytep row));
3104
#if defined(PNG_READ_RGB_TO_GRAY_SUPPORTED)
3105
PNG_EXTERN int png_do_rgb_to_gray PNGARG((png_structp png_ptr, png_row_infop
3106
row_info, png_bytep row));
3109
#if defined(PNG_READ_GRAY_TO_RGB_SUPPORTED)
3110
PNG_EXTERN void png_do_gray_to_rgb PNGARG((png_row_infop row_info,
3114
#if defined(PNG_READ_PACK_SUPPORTED)
3115
PNG_EXTERN void png_do_unpack PNGARG((png_row_infop row_info, png_bytep row));
3118
#if defined(PNG_READ_SHIFT_SUPPORTED)
3119
PNG_EXTERN void png_do_unshift PNGARG((png_row_infop row_info, png_bytep row,
3120
png_color_8p sig_bits));
3123
#if defined(PNG_READ_INVERT_SUPPORTED) || defined(PNG_WRITE_INVERT_SUPPORTED)
3124
PNG_EXTERN void png_do_invert PNGARG((png_row_infop row_info, png_bytep row));
3127
#if defined(PNG_READ_16_TO_8_SUPPORTED)
3128
PNG_EXTERN void png_do_chop PNGARG((png_row_infop row_info, png_bytep row));
3131
#if defined(PNG_READ_DITHER_SUPPORTED)
3132
PNG_EXTERN void png_do_dither PNGARG((png_row_infop row_info,
3133
png_bytep row, png_bytep palette_lookup, png_bytep dither_lookup));
3135
# if defined(PNG_CORRECT_PALETTE_SUPPORTED)
3136
PNG_EXTERN void png_correct_palette PNGARG((png_structp png_ptr,
3137
png_colorp palette, int num_palette));
3141
#if defined(PNG_READ_BGR_SUPPORTED) || defined(PNG_WRITE_BGR_SUPPORTED)
3142
PNG_EXTERN void png_do_bgr PNGARG((png_row_infop row_info, png_bytep row));
3145
#if defined(PNG_WRITE_PACK_SUPPORTED)
3146
PNG_EXTERN void png_do_pack PNGARG((png_row_infop row_info,
3147
png_bytep row, png_uint_32 bit_depth));
3150
#if defined(PNG_WRITE_SHIFT_SUPPORTED)
3151
PNG_EXTERN void png_do_shift PNGARG((png_row_infop row_info, png_bytep row,
3152
png_color_8p bit_depth));
3155
#if defined(PNG_READ_BACKGROUND_SUPPORTED)
3156
#if defined(PNG_READ_GAMMA_SUPPORTED)
3157
PNG_EXTERN void png_do_background PNGARG((png_row_infop row_info, png_bytep row,
3158
png_color_16p trans_values, png_color_16p background,
3159
png_color_16p background_1,
3160
png_bytep gamma_table, png_bytep gamma_from_1, png_bytep gamma_to_1,
3161
png_uint_16pp gamma_16, png_uint_16pp gamma_16_from_1,
3162
png_uint_16pp gamma_16_to_1, int gamma_shift));
3164
PNG_EXTERN void png_do_background PNGARG((png_row_infop row_info, png_bytep row,
3165
png_color_16p trans_values, png_color_16p background));
3169
#if defined(PNG_READ_GAMMA_SUPPORTED)
3170
PNG_EXTERN void png_do_gamma PNGARG((png_row_infop row_info, png_bytep row,
3171
png_bytep gamma_table, png_uint_16pp gamma_16_table,
3175
#if defined(PNG_READ_EXPAND_SUPPORTED)
3176
PNG_EXTERN void png_do_expand_palette PNGARG((png_row_infop row_info,
3177
png_bytep row, png_colorp palette, png_bytep trans, int num_trans));
3178
PNG_EXTERN void png_do_expand PNGARG((png_row_infop row_info,
3179
png_bytep row, png_color_16p trans_value));
3182
/* The following decodes the appropriate chunks, and does error correction,
3183
* then calls the appropriate callback for the chunk if it is valid.
3186
/* decode the IHDR chunk */
3187
PNG_EXTERN void png_handle_IHDR PNGARG((png_structp png_ptr, png_infop info_ptr,
3188
png_uint_32 length));
3189
PNG_EXTERN void png_handle_PLTE PNGARG((png_structp png_ptr, png_infop info_ptr,
3190
png_uint_32 length));
3191
PNG_EXTERN void png_handle_IEND PNGARG((png_structp png_ptr, png_infop info_ptr,
3192
png_uint_32 length));
3194
#if defined(PNG_READ_bKGD_SUPPORTED)
3195
PNG_EXTERN void png_handle_bKGD PNGARG((png_structp png_ptr, png_infop info_ptr,
3196
png_uint_32 length));
3199
#if defined(PNG_READ_cHRM_SUPPORTED)
3200
PNG_EXTERN void png_handle_cHRM PNGARG((png_structp png_ptr, png_infop info_ptr,
3201
png_uint_32 length));
3204
#if defined(PNG_READ_gAMA_SUPPORTED)
3205
PNG_EXTERN void png_handle_gAMA PNGARG((png_structp png_ptr, png_infop info_ptr,
3206
png_uint_32 length));
3209
#if defined(PNG_READ_hIST_SUPPORTED)
3210
PNG_EXTERN void png_handle_hIST PNGARG((png_structp png_ptr, png_infop info_ptr,
3211
png_uint_32 length));
3214
#if defined(PNG_READ_iCCP_SUPPORTED)
3215
extern void png_handle_iCCP PNGARG((png_structp png_ptr, png_infop info_ptr,
3216
png_uint_32 length));
3217
#endif /* PNG_READ_iCCP_SUPPORTED */
3219
#if defined(PNG_READ_iTXt_SUPPORTED)
3220
PNG_EXTERN void png_handle_iTXt PNGARG((png_structp png_ptr, png_infop info_ptr,
3221
png_uint_32 length));
3224
#if defined(PNG_READ_oFFs_SUPPORTED)
3225
PNG_EXTERN void png_handle_oFFs PNGARG((png_structp png_ptr, png_infop info_ptr,
3226
png_uint_32 length));
3229
#if defined(PNG_READ_pCAL_SUPPORTED)
3230
PNG_EXTERN void png_handle_pCAL PNGARG((png_structp png_ptr, png_infop info_ptr,
3231
png_uint_32 length));
3234
#if defined(PNG_READ_pHYs_SUPPORTED)
3235
PNG_EXTERN void png_handle_pHYs PNGARG((png_structp png_ptr, png_infop info_ptr,
3236
png_uint_32 length));
3239
#if defined(PNG_READ_sBIT_SUPPORTED)
3240
PNG_EXTERN void png_handle_sBIT PNGARG((png_structp png_ptr, png_infop info_ptr,
3241
png_uint_32 length));
3244
#if defined(PNG_READ_sCAL_SUPPORTED)
3245
PNG_EXTERN void png_handle_sCAL PNGARG((png_structp png_ptr, png_infop info_ptr,
3246
png_uint_32 length));
3249
#if defined(PNG_READ_sPLT_SUPPORTED)
3250
extern void png_handle_sPLT PNGARG((png_structp png_ptr, png_infop info_ptr,
3251
png_uint_32 length));
3252
#endif /* PNG_READ_sPLT_SUPPORTED */
3254
#if defined(PNG_READ_sRGB_SUPPORTED)
3255
PNG_EXTERN void png_handle_sRGB PNGARG((png_structp png_ptr, png_infop info_ptr,
3256
png_uint_32 length));
3259
#if defined(PNG_READ_tEXt_SUPPORTED)
3260
PNG_EXTERN void png_handle_tEXt PNGARG((png_structp png_ptr, png_infop info_ptr,
3261
png_uint_32 length));
3264
#if defined(PNG_READ_tIME_SUPPORTED)
3265
PNG_EXTERN void png_handle_tIME PNGARG((png_structp png_ptr, png_infop info_ptr,
3266
png_uint_32 length));
3269
#if defined(PNG_READ_tRNS_SUPPORTED)
3270
PNG_EXTERN void png_handle_tRNS PNGARG((png_structp png_ptr, png_infop info_ptr,
3271
png_uint_32 length));
3274
#if defined(PNG_READ_zTXt_SUPPORTED)
3275
PNG_EXTERN void png_handle_zTXt PNGARG((png_structp png_ptr, png_infop info_ptr,
3276
png_uint_32 length));
3279
PNG_EXTERN void png_handle_unknown PNGARG((png_structp png_ptr,
3280
png_infop info_ptr, png_uint_32 length));
3282
PNG_EXTERN void png_check_chunk_name PNGARG((png_structp png_ptr,
3283
png_bytep chunk_name));
3285
/* handle the transformations for reading and writing */
3286
PNG_EXTERN void png_do_read_transformations PNGARG((png_structp png_ptr));
3287
PNG_EXTERN void png_do_write_transformations PNGARG((png_structp png_ptr));
3289
PNG_EXTERN void png_init_read_transformations PNGARG((png_structp png_ptr));
3291
#ifdef PNG_PROGRESSIVE_READ_SUPPORTED
3292
PNG_EXTERN void png_push_read_chunk PNGARG((png_structp png_ptr,
3293
png_infop info_ptr));
3294
PNG_EXTERN void png_push_read_sig PNGARG((png_structp png_ptr,
3295
png_infop info_ptr));
3296
PNG_EXTERN void png_push_check_crc PNGARG((png_structp png_ptr));
3297
PNG_EXTERN void png_push_crc_skip PNGARG((png_structp png_ptr,
3298
png_uint_32 length));
3299
PNG_EXTERN void png_push_crc_finish PNGARG((png_structp png_ptr));
3300
PNG_EXTERN void png_push_save_buffer PNGARG((png_structp png_ptr));
3301
PNG_EXTERN void png_push_restore_buffer PNGARG((png_structp png_ptr,
3302
png_bytep buffer, png_size_t buffer_length));
3303
PNG_EXTERN void png_push_read_IDAT PNGARG((png_structp png_ptr));
3304
PNG_EXTERN void png_process_IDAT_data PNGARG((png_structp png_ptr,
3305
png_bytep buffer, png_size_t buffer_length));
3306
PNG_EXTERN void png_push_process_row PNGARG((png_structp png_ptr));
3307
PNG_EXTERN void png_push_handle_unknown PNGARG((png_structp png_ptr,
3308
png_infop info_ptr, png_uint_32 length));
3309
PNG_EXTERN void png_push_have_info PNGARG((png_structp png_ptr,
3310
png_infop info_ptr));
3311
PNG_EXTERN void png_push_have_end PNGARG((png_structp png_ptr,
3312
png_infop info_ptr));
3313
PNG_EXTERN void png_push_have_row PNGARG((png_structp png_ptr, png_bytep row));
3314
PNG_EXTERN void png_push_read_end PNGARG((png_structp png_ptr,
3315
png_infop info_ptr));
3316
PNG_EXTERN void png_process_some_data PNGARG((png_structp png_ptr,
3317
png_infop info_ptr));
3318
PNG_EXTERN void png_read_push_finish_row PNGARG((png_structp png_ptr));
3319
#if defined(PNG_READ_tEXt_SUPPORTED)
3320
PNG_EXTERN void png_push_handle_tEXt PNGARG((png_structp png_ptr,
3321
png_infop info_ptr, png_uint_32 length));
3322
PNG_EXTERN void png_push_read_tEXt PNGARG((png_structp png_ptr,
3323
png_infop info_ptr));
3325
#if defined(PNG_READ_zTXt_SUPPORTED)
3326
PNG_EXTERN void png_push_handle_zTXt PNGARG((png_structp png_ptr,
3327
png_infop info_ptr, png_uint_32 length));
3328
PNG_EXTERN void png_push_read_zTXt PNGARG((png_structp png_ptr,
3329
png_infop info_ptr));
3331
#if defined(PNG_READ_iTXt_SUPPORTED)
3332
PNG_EXTERN void png_push_handle_iTXt PNGARG((png_structp png_ptr,
3333
png_infop info_ptr, png_uint_32 length));
3334
PNG_EXTERN void png_push_read_iTXt PNGARG((png_structp png_ptr,
3335
png_infop info_ptr));
3338
#endif /* PNG_PROGRESSIVE_READ_SUPPORTED */
3340
#ifdef PNG_MNG_FEATURES_SUPPORTED
3341
PNG_EXTERN void png_do_read_intrapixel PNGARG((png_row_infop row_info,
3343
PNG_EXTERN void png_do_write_intrapixel PNGARG((png_row_infop row_info,
3347
#if defined(PNG_ASSEMBLER_CODE_SUPPORTED)
3348
/* png.c */ /* PRIVATE */
3349
PNG_EXTERN void png_init_mmx_flags PNGARG((png_structp png_ptr));
3351
/* Maintainer: Put new private prototypes here ^ and in libpngpf.3 */
3353
#endif /* PNG_INTERNAL */
3359
#endif /* PNG_VERSION_INFO_ONLY */
3360
/* do not put anything past this line */
added
removed
utils/TkCximage/src/png/png.h
