1
2/* png.h - header file for PNG reference library
3 *
4 * libpng version 1.6.36 - December 1, 2018
5 *
6 * Copyright (c) 2018 Cosmin Truta
7 * Copyright (c) 1998-2002,2004,2006-2018 Glenn Randers-Pehrson
8 * Copyright (c) 1996-1997 Andreas Dilger
9 * Copyright (c) 1995-1996 Guy Eric Schalnat, Group 42, Inc.
10 *
11 * This code is released under the libpng license. (See LICENSE, below.)
12 *
13 * Authors and maintainers:
14 * libpng versions 0.71, May 1995, through 0.88, January 1996: Guy Schalnat
15 * libpng versions 0.89, June 1996, through 0.96, May 1997: Andreas Dilger
16 * libpng versions 0.97, January 1998, through 1.6.35, July 2018:
17 * Glenn Randers-Pehrson.
18 * libpng version 1.6.36, December 1, 2018: Cosmin Truta
19 * See also "Contributing Authors", below.
20 */
21
22/*
23 * COPYRIGHT NOTICE, DISCLAIMER, and LICENSE
24 * =========================================
25 *
26 * PNG Reference Library License version 2
27 * ---------------------------------------
28 *
29 * * Copyright (c) 1995-2018 The PNG Reference Library Authors.
30 * * Copyright (c) 2018 Cosmin Truta.
31 * * Copyright (c) 2000-2002, 2004, 2006-2018 Glenn Randers-Pehrson.
32 * * Copyright (c) 1996-1997 Andreas Dilger.
33 * * Copyright (c) 1995-1996 Guy Eric Schalnat, Group 42, Inc.
34 *
35 * The software is supplied "as is", without warranty of any kind,
36 * express or implied, including, without limitation, the warranties
37 * of merchantability, fitness for a particular purpose, title, and
38 * non-infringement. In no even shall the Copyright owners, or
39 * anyone distributing the software, be liable for any damages or
40 * other liability, whether in contract, tort or otherwise, arising
41 * from, out of, or in connection with the software, or the use or
42 * other dealings in the software, even if advised of the possibility
43 * of such damage.
44 *
45 * Permission is hereby granted to use, copy, modify, and distribute
46 * this software, or portions hereof, for any purpose, without fee,
47 * subject to the following restrictions:
48 *
49 * 1. The origin of this software must not be misrepresented; you
50 * must not claim that you wrote the original software. If you
51 * use this software in a product, an acknowledgment in the product
52 * documentation would be appreciated, but is not required.
53 *
54 * 2. Altered source versions must be plainly marked as such, and must
55 * not be misrepresented as being the original software.
56 *
57 * 3. This Copyright notice may not be removed or altered from any
58 * source or altered source distribution.
59 *
60 *
61 * PNG Reference Library License version 1 (for libpng 0.5 through 1.6.35)
62 * -----------------------------------------------------------------------
63 *
64 * libpng versions 1.0.7, July 1, 2000 through 1.6.35, July 15, 2018 are
65 * Copyright (c) 2000-2002, 2004, 2006-2018 Glenn Randers-Pehrson, are
66 * derived from libpng-1.0.6, and are distributed according to the same
67 * disclaimer and license as libpng-1.0.6 with the following individuals
68 * added to the list of Contributing Authors:
69 *
70 * Simon-Pierre Cadieux
71 * Eric S. Raymond
72 * Mans Rullgard
73 * Cosmin Truta
74 * Gilles Vollant
75 * James Yu
76 * Mandar Sahastrabuddhe
77 * Google Inc.
78 * Vadim Barkov
79 *
80 * and with the following additions to the disclaimer:
81 *
82 * There is no warranty against interference with your enjoyment of
83 * the library or against infringement. There is no warranty that our
84 * efforts or the library will fulfill any of your particular purposes
85 * or needs. This library is provided with all faults, and the entire
86 * risk of satisfactory quality, performance, accuracy, and effort is
87 * with the user.
88 *
89 * Some files in the "contrib" directory and some configure-generated
90 * files that are distributed with libpng have other copyright owners, and
91 * are released under other open source licenses.
92 *
93 * libpng versions 0.97, January 1998, through 1.0.6, March 20, 2000, are
94 * Copyright (c) 1998-2000 Glenn Randers-Pehrson, are derived from
95 * libpng-0.96, and are distributed according to the same disclaimer and
96 * license as libpng-0.96, with the following individuals added to the
97 * list of Contributing Authors:
98 *
99 * Tom Lane
100 * Glenn Randers-Pehrson
101 * Willem van Schaik
102 *
103 * libpng versions 0.89, June 1996, through 0.96, May 1997, are
104 * Copyright (c) 1996-1997 Andreas Dilger, are derived from libpng-0.88,
105 * and are distributed according to the same disclaimer and license as
106 * libpng-0.88, with the following individuals added to the list of
107 * Contributing Authors:
108 *
109 * John Bowler
110 * Kevin Bracey
111 * Sam Bushell
112 * Magnus Holmgren
113 * Greg Roelofs
114 * Tom Tanner
115 *
116 * Some files in the "scripts" directory have other copyright owners,
117 * but are released under this license.
118 *
119 * libpng versions 0.5, May 1995, through 0.88, January 1996, are
120 * Copyright (c) 1995-1996 Guy Eric Schalnat, Group 42, Inc.
121 *
122 * For the purposes of this copyright and license, "Contributing Authors"
123 * is defined as the following set of individuals:
124 *
125 * Andreas Dilger
126 * Dave Martindale
127 * Guy Eric Schalnat
128 * Paul Schmidt
129 * Tim Wegner
130 *
131 * The PNG Reference Library is supplied "AS IS". The Contributing
132 * Authors and Group 42, Inc. disclaim all warranties, expressed or
133 * implied, including, without limitation, the warranties of
134 * merchantability and of fitness for any purpose. The Contributing
135 * Authors and Group 42, Inc. assume no liability for direct, indirect,
136 * incidental, special, exemplary, or consequential damages, which may
137 * result from the use of the PNG Reference Library, even if advised of
138 * the possibility of such damage.
139 *
140 * Permission is hereby granted to use, copy, modify, and distribute this
141 * source code, or portions hereof, for any purpose, without fee, subject
142 * to the following restrictions:
143 *
144 * 1. The origin of this source code must not be misrepresented.
145 *
146 * 2. Altered versions must be plainly marked as such and must not
147 * be misrepresented as being the original source.
148 *
149 * 3. This Copyright notice may not be removed or altered from any
150 * source or altered source distribution.
151 *
152 * The Contributing Authors and Group 42, Inc. specifically permit,
153 * without fee, and encourage the use of this source code as a component
154 * to supporting the PNG file format in commercial products. If you use
155 * this source code in a product, acknowledgment is not required but would
156 * be appreciated.
157 *
158 * END OF COPYRIGHT NOTICE, DISCLAIMER, and LICENSE.
159 *
160 * TRADEMARK
161 * =========
162 *
163 * The name "libpng" has not been registered by the Copyright owners
164 * as a trademark in any jurisdiction. However, because libpng has
165 * been distributed and maintained world-wide, continually since 1995,
166 * the Copyright owners claim "common-law trademark protection" in any
167 * jurisdiction where common-law trademark is recognized.
168 */
169
170/*
171 * A "png_get_copyright" function is available, for convenient use in "about"
172 * boxes and the like:
173 *
174 * printf("%s", png_get_copyright(NULL));
175 *
176 * Also, the PNG logo (in PNG format, of course) is supplied in the
177 * files "pngbar.png" and "pngbar.jpg (88x31) and "pngnow.png" (98x31).
178 */
179
180/*
181 * The contributing authors would like to thank all those who helped
182 * with testing, bug fixes, and patience. This wouldn't have been
183 * possible without all of you.
184 *
185 * Thanks to Frank J. T. Wojcik for helping with the documentation.
186 */
187
188/* Note about libpng version numbers:
189 *
190 * Due to various miscommunications, unforeseen code incompatibilities
191 * and occasional factors outside the authors' control, version numbering
192 * on the library has not always been consistent and straightforward.
193 * The following table summarizes matters since version 0.89c, which was
194 * the first widely used release:
195 *
196 * source png.h png.h shared-lib
197 * version string int version
198 * ------- ------ ----- ----------
199 * 0.89c "1.0 beta 3" 0.89 89 1.0.89
200 * 0.90 "1.0 beta 4" 0.90 90 0.90 [should have been 2.0.90]
201 * 0.95 "1.0 beta 5" 0.95 95 0.95 [should have been 2.0.95]
202 * 0.96 "1.0 beta 6" 0.96 96 0.96 [should have been 2.0.96]
203 * 0.97b "1.00.97 beta 7" 1.00.97 97 1.0.1 [should have been 2.0.97]
204 * 0.97c 0.97 97 2.0.97
205 * 0.98 0.98 98 2.0.98
206 * 0.99 0.99 98 2.0.99
207 * 0.99a-m 0.99 99 2.0.99
208 * 1.00 1.00 100 2.1.0 [100 should be 10000]
209 * 1.0.0 (from here on, the 100 2.1.0 [100 should be 10000]
210 * 1.0.1 png.h string is 10001 2.1.0
211 * 1.0.1a-e identical to the 10002 from here on, the shared library
212 * 1.0.2 source version) 10002 is 2.V where V is the source code
213 * 1.0.2a-b 10003 version, except as noted.
214 * 1.0.3 10003
215 * 1.0.3a-d 10004
216 * 1.0.4 10004
217 * 1.0.4a-f 10005
218 * 1.0.5 (+ 2 patches) 10005
219 * 1.0.5a-d 10006
220 * 1.0.5e-r 10100 (not source compatible)
221 * 1.0.5s-v 10006 (not binary compatible)
222 * 1.0.6 (+ 3 patches) 10006 (still binary incompatible)
223 * 1.0.6d-f 10007 (still binary incompatible)
224 * 1.0.6g 10007
225 * 1.0.6h 10007 10.6h (testing xy.z so-numbering)
226 * 1.0.6i 10007 10.6i
227 * 1.0.6j 10007 2.1.0.6j (incompatible with 1.0.0)
228 * 1.0.7beta11-14 DLLNUM 10007 2.1.0.7beta11-14 (binary compatible)
229 * 1.0.7beta15-18 1 10007 2.1.0.7beta15-18 (binary compatible)
230 * 1.0.7rc1-2 1 10007 2.1.0.7rc1-2 (binary compatible)
231 * 1.0.7 1 10007 (still compatible)
232 * ...
233 * 1.0.69 10 10069 10.so.0.69[.0]
234 * ...
235 * 1.2.59 13 10259 12.so.0.59[.0]
236 * ...
237 * 1.4.20 14 10420 14.so.0.20[.0]
238 * ...
239 * 1.5.30 15 10530 15.so.15.30[.0]
240 * ...
241 * 1.6.36 16 10636 16.so.16.36[.0]
242 *
243 * Henceforth the source version will match the shared-library major and
244 * minor numbers; the shared-library major version number will be used for
245 * changes in backward compatibility, as it is intended.
246 * The PNG_LIBPNG_VER macro, which is not used within libpng but is
247 * available for applications, is an unsigned integer of the form XYYZZ
248 * corresponding to the source version X.Y.Z (leading zeros in Y and Z).
249 * Beta versions were given the previous public release number plus a
250 * letter, until version 1.0.6j; from then on they were given the upcoming
251 * public release number plus "betaNN" or "rcNN".
252 *
253 * Binary incompatibility exists only when applications make direct access
254 * to the info_ptr or png_ptr members through png.h, and the compiled
255 * application is loaded with a different version of the library.
256 *
257 * DLLNUM will change each time there are forward or backward changes
258 * in binary compatibility (e.g., when a new feature is added).
259 *
260 * See libpng.txt or libpng.3 for more information. The PNG specification
261 * is available as a W3C Recommendation and as an ISO/IEC Standard; see
262 * <https://www.w3.org/TR/2003/REC-PNG-20031110/>
263 */
264
265#ifndef PNG_H
266#define PNG_H
267
268/* This is not the place to learn how to use libpng. The file libpng-manual.txt
269 * describes how to use libpng, and the file example.c summarizes it
270 * with some code on which to build. This file is useful for looking
271 * at the actual function definitions and structure components. If that
272 * file has been stripped from your copy of libpng, you can find it at
273 * <http://www.libpng.org/pub/png/libpng-manual.txt>
274 *
275 * If you just need to read a PNG file and don't want to read the documentation
276 * skip to the end of this file and read the section entitled 'simplified API'.
277 */
278
279/* Version information for png.h - this should match the version in png.c */
280#define PNG_LIBPNG_VER_STRING "1.6.36"
281#define PNG_HEADER_VERSION_STRING " libpng version 1.6.36 - December 1, 2018\n"
282
283#define PNG_LIBPNG_VER_SONUM 16
284#define PNG_LIBPNG_VER_DLLNUM 16
285
286/* These should match the first 3 components of PNG_LIBPNG_VER_STRING: */
287#define PNG_LIBPNG_VER_MAJOR 1
288#define PNG_LIBPNG_VER_MINOR 6
289#define PNG_LIBPNG_VER_RELEASE 36
290
291/* This should match the numeric part of the final component of
292 * PNG_LIBPNG_VER_STRING, omitting any leading zero:
293 */
294
295#define PNG_LIBPNG_VER_BUILD 0
296
297/* Release Status */
298#define PNG_LIBPNG_BUILD_ALPHA 1
299#define PNG_LIBPNG_BUILD_BETA 2
300#define PNG_LIBPNG_BUILD_RC 3
301#define PNG_LIBPNG_BUILD_STABLE 4
302#define PNG_LIBPNG_BUILD_RELEASE_STATUS_MASK 7
303
304/* Release-Specific Flags */
305#define PNG_LIBPNG_BUILD_PATCH 8 /* Can be OR'ed with
306 PNG_LIBPNG_BUILD_STABLE only */
307#define PNG_LIBPNG_BUILD_PRIVATE 16 /* Cannot be OR'ed with
308 PNG_LIBPNG_BUILD_SPECIAL */
309#define PNG_LIBPNG_BUILD_SPECIAL 32 /* Cannot be OR'ed with
310 PNG_LIBPNG_BUILD_PRIVATE */
311
312#define PNG_LIBPNG_BUILD_BASE_TYPE PNG_LIBPNG_BUILD_STABLE
313
314/* Careful here. At one time, Guy wanted to use 082, but that
315 * would be octal. We must not include leading zeros.
316 * Versions 0.7 through 1.0.0 were in the range 0 to 100 here
317 * (only version 1.0.0 was mis-numbered 100 instead of 10000).
318 * From version 1.0.1 it is:
319 * XXYYZZ, where XX=major, YY=minor, ZZ=release
320 */
321#define PNG_LIBPNG_VER 10636 /* 1.6.36 */
322
323/* Library configuration: these options cannot be changed after
324 * the library has been built.
325 */
326#ifndef PNGLCONF_H
327/* If pnglibconf.h is missing, you can
328 * copy scripts/pnglibconf.h.prebuilt to pnglibconf.h
329 */
330# include "pnglibconf.h"
331#endif
332
333#define PNG_APNG_SUPPORTED
334#define PNG_READ_APNG_SUPPORTED
335#define PNG_WRITE_APNG_SUPPORTED
336
337#ifndef PNG_VERSION_INFO_ONLY
338/* Machine specific configuration. */
339# include "pngconf.h"
340#endif
341
342/*
343 * Added at libpng-1.2.8
344 *
345 * Ref MSDN: Private as priority over Special
346 * VS_FF_PRIVATEBUILD File *was not* built using standard release
347 * procedures. If this value is given, the StringFileInfo block must
348 * contain a PrivateBuild string.
349 *
350 * VS_FF_SPECIALBUILD File *was* built by the original company using
351 * standard release procedures but is a variation of the standard
352 * file of the same version number. If this value is given, the
353 * StringFileInfo block must contain a SpecialBuild string.
354 */
355
356#ifdef PNG_USER_PRIVATEBUILD /* From pnglibconf.h */
357# define PNG_LIBPNG_BUILD_TYPE \
358 (PNG_LIBPNG_BUILD_BASE_TYPE | PNG_LIBPNG_BUILD_PRIVATE)
359#else
360# ifdef PNG_LIBPNG_SPECIALBUILD
361# define PNG_LIBPNG_BUILD_TYPE \
362 (PNG_LIBPNG_BUILD_BASE_TYPE | PNG_LIBPNG_BUILD_SPECIAL)
363# else
364# define PNG_LIBPNG_BUILD_TYPE (PNG_LIBPNG_BUILD_BASE_TYPE)
365# endif
366#endif
367
368#ifndef PNG_VERSION_INFO_ONLY
369
370/* Inhibit C++ name-mangling for libpng functions but not for system calls. */
371#ifdef __cplusplus
372extern "C" {
373#endif /* __cplusplus */
374
375/* Version information for C files, stored in png.c. This had better match
376 * the version above.
377 */
378#define png_libpng_ver png_get_header_ver(NULL)
379
380/* This file is arranged in several sections:
381 *
382 * 1. [omitted]
383 * 2. Any configuration options that can be specified by for the application
384 * code when it is built. (Build time configuration is in pnglibconf.h)
385 * 3. Type definitions (base types are defined in pngconf.h), structure
386 * definitions.
387 * 4. Exported library functions.
388 * 5. Simplified API.
389 * 6. Implementation options.
390 *
391 * The library source code has additional files (principally pngpriv.h) that
392 * allow configuration of the library.
393 */
394
395/* Section 1: [omitted] */
396
397/* Section 2: run time configuration
398 * See pnglibconf.h for build time configuration
399 *
400 * Run time configuration allows the application to choose between
401 * implementations of certain arithmetic APIs. The default is set
402 * at build time and recorded in pnglibconf.h, but it is safe to
403 * override these (and only these) settings. Note that this won't
404 * change what the library does, only application code, and the
405 * settings can (and probably should) be made on a per-file basis
406 * by setting the #defines before including png.h
407 *
408 * Use macros to read integers from PNG data or use the exported
409 * functions?
410 * PNG_USE_READ_MACROS: use the macros (see below) Note that
411 * the macros evaluate their argument multiple times.
412 * PNG_NO_USE_READ_MACROS: call the relevant library function.
413 *
414 * Use the alternative algorithm for compositing alpha samples that
415 * does not use division?
416 * PNG_READ_COMPOSITE_NODIV_SUPPORTED: use the 'no division'
417 * algorithm.
418 * PNG_NO_READ_COMPOSITE_NODIV: use the 'division' algorithm.
419 *
420 * How to handle benign errors if PNG_ALLOW_BENIGN_ERRORS is
421 * false?
422 * PNG_ALLOW_BENIGN_ERRORS: map calls to the benign error
423 * APIs to png_warning.
424 * Otherwise the calls are mapped to png_error.
425 */
426
427/* Section 3: type definitions, including structures and compile time
428 * constants.
429 * See pngconf.h for base types that vary by machine/system
430 */
431
432#ifdef PNG_APNG_SUPPORTED
433/* dispose_op flags from inside fcTL */
434#define PNG_DISPOSE_OP_NONE 0x00U
435#define PNG_DISPOSE_OP_BACKGROUND 0x01U
436#define PNG_DISPOSE_OP_PREVIOUS 0x02U
437
438/* blend_op flags from inside fcTL */
439#define PNG_BLEND_OP_SOURCE 0x00U
440#define PNG_BLEND_OP_OVER 0x01U
441#endif /* PNG_APNG_SUPPORTED */
442
443/* This triggers a compiler error in png.c, if png.c and png.h
444 * do not agree upon the version number.
445 */
446typedef char* png_libpng_version_1_6_36;
447
448/* Basic control structions. Read libpng-manual.txt or libpng.3 for more info.
449 *
450 * png_struct is the cache of information used while reading or writing a single
451 * PNG file. One of these is always required, although the simplified API
452 * (below) hides the creation and destruction of it.
453 */
454typedef struct png_struct_def png_struct;
455typedef const png_struct * png_const_structp;
456typedef png_struct * png_structp;
457typedef png_struct * * png_structpp;
458
459/* png_info contains information read from or to be written to a PNG file. One
460 * or more of these must exist while reading or creating a PNG file. The
461 * information is not used by libpng during read but is used to control what
462 * gets written when a PNG file is created. "png_get_" function calls read
463 * information during read and "png_set_" functions calls write information
464 * when creating a PNG.
465 * been moved into a separate header file that is not accessible to
466 * applications. Read libpng-manual.txt or libpng.3 for more info.
467 */
468typedef struct png_info_def png_info;
469typedef png_info * png_infop;
470typedef const png_info * png_const_infop;
471typedef png_info * * png_infopp;
472
473/* Types with names ending 'p' are pointer types. The corresponding types with
474 * names ending 'rp' are identical pointer types except that the pointer is
475 * marked 'restrict', which means that it is the only pointer to the object
476 * passed to the function. Applications should not use the 'restrict' types;
477 * it is always valid to pass 'p' to a pointer with a function argument of the
478 * corresponding 'rp' type. Different compilers have different rules with
479 * regard to type matching in the presence of 'restrict'. For backward
480 * compatibility libpng callbacks never have 'restrict' in their parameters and,
481 * consequentially, writing portable application code is extremely difficult if
482 * an attempt is made to use 'restrict'.
483 */
484typedef png_struct * PNG_RESTRICT png_structrp;
485typedef const png_struct * PNG_RESTRICT png_const_structrp;
486typedef png_info * PNG_RESTRICT png_inforp;
487typedef const png_info * PNG_RESTRICT png_const_inforp;
488
489/* Three color definitions. The order of the red, green, and blue, (and the
490 * exact size) is not important, although the size of the fields need to
491 * be png_byte or png_uint_16 (as defined below).
492 */
493typedef struct png_color_struct
494{
495 png_byte red;
496 png_byte green;
497 png_byte blue;
498} png_color;
499typedef png_color * png_colorp;
500typedef const png_color * png_const_colorp;
501typedef png_color * * png_colorpp;
502
503typedef struct png_color_16_struct
504{
505 png_byte index; /* used for palette files */
506 png_uint_16 red; /* for use in red green blue files */
507 png_uint_16 green;
508 png_uint_16 blue;
509 png_uint_16 gray; /* for use in grayscale files */
510} png_color_16;
511typedef png_color_16 * png_color_16p;
512typedef const png_color_16 * png_const_color_16p;
513typedef png_color_16 * * png_color_16pp;
514
515typedef struct png_color_8_struct
516{
517 png_byte red; /* for use in red green blue files */
518 png_byte green;
519 png_byte blue;
520 png_byte gray; /* for use in grayscale files */
521 png_byte alpha; /* for alpha channel files */
522} png_color_8;
523typedef png_color_8 * png_color_8p;
524typedef const png_color_8 * png_const_color_8p;
525typedef png_color_8 * * png_color_8pp;
526
527/*
528 * The following two structures are used for the in-core representation
529 * of sPLT chunks.
530 */
531typedef struct png_sPLT_entry_struct
532{
533 png_uint_16 red;
534 png_uint_16 green;
535 png_uint_16 blue;
536 png_uint_16 alpha;
537 png_uint_16 frequency;
538} png_sPLT_entry;
539typedef png_sPLT_entry * png_sPLT_entryp;
540typedef const png_sPLT_entry * png_const_sPLT_entryp;
541typedef png_sPLT_entry * * png_sPLT_entrypp;
542
543/* When the depth of the sPLT palette is 8 bits, the color and alpha samples
544 * occupy the LSB of their respective members, and the MSB of each member
545 * is zero-filled. The frequency member always occupies the full 16 bits.
546 */
547
548typedef struct png_sPLT_struct
549{
550 png_charp name; /* palette name */
551 png_byte depth; /* depth of palette samples */
552 png_sPLT_entryp entries; /* palette entries */
553 png_int_32 nentries; /* number of palette entries */
554} png_sPLT_t;
555typedef png_sPLT_t * png_sPLT_tp;
556typedef const png_sPLT_t * png_const_sPLT_tp;
557typedef png_sPLT_t * * png_sPLT_tpp;
558
559#ifdef PNG_TEXT_SUPPORTED
560/* png_text holds the contents of a text/ztxt/itxt chunk in a PNG file,
561 * and whether that contents is compressed or not. The "key" field
562 * points to a regular zero-terminated C string. The "text" fields can be a
563 * regular C string, an empty string, or a NULL pointer.
564 * However, the structure returned by png_get_text() will always contain
565 * the "text" field as a regular zero-terminated C string (possibly
566 * empty), never a NULL pointer, so it can be safely used in printf() and
567 * other string-handling functions. Note that the "itxt_length", "lang", and
568 * "lang_key" members of the structure only exist when the library is built
569 * with iTXt chunk support. Prior to libpng-1.4.0 the library was built by
570 * default without iTXt support. Also note that when iTXt *is* supported,
571 * the "lang" and "lang_key" fields contain NULL pointers when the
572 * "compression" field contains * PNG_TEXT_COMPRESSION_NONE or
573 * PNG_TEXT_COMPRESSION_zTXt. Note that the "compression value" is not the
574 * same as what appears in the PNG tEXt/zTXt/iTXt chunk's "compression flag"
575 * which is always 0 or 1, or its "compression method" which is always 0.
576 */
577typedef struct png_text_struct
578{
579 int compression; /* compression value:
580 -1: tEXt, none
581 0: zTXt, deflate
582 1: iTXt, none
583 2: iTXt, deflate */
584 png_charp key; /* keyword, 1-79 character description of "text" */
585 png_charp text; /* comment, may be an empty string (ie "")
586 or a NULL pointer */
587 size_t text_length; /* length of the text string */
588 size_t itxt_length; /* length of the itxt string */
589 png_charp lang; /* language code, 0-79 characters
590 or a NULL pointer */
591 png_charp lang_key; /* keyword translated UTF-8 string, 0 or more
592 chars or a NULL pointer */
593} png_text;
594typedef png_text * png_textp;
595typedef const png_text * png_const_textp;
596typedef png_text * * png_textpp;
597#endif
598
599/* Supported compression types for text in PNG files (tEXt, and zTXt).
600 * The values of the PNG_TEXT_COMPRESSION_ defines should NOT be changed. */
601#define PNG_TEXT_COMPRESSION_NONE_WR -3
602#define PNG_TEXT_COMPRESSION_zTXt_WR -2
603#define PNG_TEXT_COMPRESSION_NONE -1
604#define PNG_TEXT_COMPRESSION_zTXt 0
605#define PNG_ITXT_COMPRESSION_NONE 1
606#define PNG_ITXT_COMPRESSION_zTXt 2
607#define PNG_TEXT_COMPRESSION_LAST 3 /* Not a valid value */
608
609/* png_time is a way to hold the time in an machine independent way.
610 * Two conversions are provided, both from time_t and struct tm. There
611 * is no portable way to convert to either of these structures, as far
612 * as I know. If you know of a portable way, send it to me. As a side
613 * note - PNG has always been Year 2000 compliant!
614 */
615typedef struct png_time_struct
616{
617 png_uint_16 year; /* full year, as in, 1995 */
618 png_byte month; /* month of year, 1 - 12 */
619 png_byte day; /* day of month, 1 - 31 */
620 png_byte hour; /* hour of day, 0 - 23 */
621 png_byte minute; /* minute of hour, 0 - 59 */
622 png_byte second; /* second of minute, 0 - 60 (for leap seconds) */
623} png_time;
624typedef png_time * png_timep;
625typedef const png_time * png_const_timep;
626typedef png_time * * png_timepp;
627
628#if defined(PNG_STORE_UNKNOWN_CHUNKS_SUPPORTED) ||\
629 defined(PNG_USER_CHUNKS_SUPPORTED)
630/* png_unknown_chunk is a structure to hold queued chunks for which there is
631 * no specific support. The idea is that we can use this to queue
632 * up private chunks for output even though the library doesn't actually
633 * know about their semantics.
634 *
635 * The data in the structure is set by libpng on read and used on write.
636 */
637typedef struct png_unknown_chunk_t
638{
639 png_byte name[5]; /* Textual chunk name with '\0' terminator */
640 png_byte *data; /* Data, should not be modified on read! */
641 size_t size;
642
643 /* On write 'location' must be set using the flag values listed below.
644 * Notice that on read it is set by libpng however the values stored have
645 * more bits set than are listed below. Always treat the value as a
646 * bitmask. On write set only one bit - setting multiple bits may cause the
647 * chunk to be written in multiple places.
648 */
649 png_byte location; /* mode of operation at read time */
650}
651png_unknown_chunk;
652
653typedef png_unknown_chunk * png_unknown_chunkp;
654typedef const png_unknown_chunk * png_const_unknown_chunkp;
655typedef png_unknown_chunk * * png_unknown_chunkpp;
656#endif
657
658/* Flag values for the unknown chunk location byte. */
659#define PNG_HAVE_IHDR 0x01
660#define PNG_HAVE_PLTE 0x02
661#define PNG_AFTER_IDAT 0x08
662
663/* Maximum positive integer used in PNG is (2^31)-1 */
664#define PNG_UINT_31_MAX ((png_uint_32)0x7fffffffL)
665#define PNG_UINT_32_MAX ((png_uint_32)(-1))
666#define PNG_SIZE_MAX ((size_t)(-1))
667
668/* These are constants for fixed point values encoded in the
669 * PNG specification manner (x100000)
670 */
671#define PNG_FP_1 100000
672#define PNG_FP_HALF 50000
673#define PNG_FP_MAX ((png_fixed_point)0x7fffffffL)
674#define PNG_FP_MIN (-PNG_FP_MAX)
675
676/* These describe the color_type field in png_info. */
677/* color type masks */
678#define PNG_COLOR_MASK_PALETTE 1
679#define PNG_COLOR_MASK_COLOR 2
680#define PNG_COLOR_MASK_ALPHA 4
681
682/* color types. Note that not all combinations are legal */
683#define PNG_COLOR_TYPE_GRAY 0
684#define PNG_COLOR_TYPE_PALETTE (PNG_COLOR_MASK_COLOR | PNG_COLOR_MASK_PALETTE)
685#define PNG_COLOR_TYPE_RGB (PNG_COLOR_MASK_COLOR)
686#define PNG_COLOR_TYPE_RGB_ALPHA (PNG_COLOR_MASK_COLOR | PNG_COLOR_MASK_ALPHA)
687#define PNG_COLOR_TYPE_GRAY_ALPHA (PNG_COLOR_MASK_ALPHA)
688/* aliases */
689#define PNG_COLOR_TYPE_RGBA PNG_COLOR_TYPE_RGB_ALPHA
690#define PNG_COLOR_TYPE_GA PNG_COLOR_TYPE_GRAY_ALPHA
691
692/* This is for compression type. PNG 1.0-1.2 only define the single type. */
693#define PNG_COMPRESSION_TYPE_BASE 0 /* Deflate method 8, 32K window */
694#define PNG_COMPRESSION_TYPE_DEFAULT PNG_COMPRESSION_TYPE_BASE
695
696/* This is for filter type. PNG 1.0-1.2 only define the single type. */
697#define PNG_FILTER_TYPE_BASE 0 /* Single row per-byte filtering */
698#define PNG_INTRAPIXEL_DIFFERENCING 64 /* Used only in MNG datastreams */
699#define PNG_FILTER_TYPE_DEFAULT PNG_FILTER_TYPE_BASE
700
701/* These are for the interlacing type. These values should NOT be changed. */
702#define PNG_INTERLACE_NONE 0 /* Non-interlaced image */
703#define PNG_INTERLACE_ADAM7 1 /* Adam7 interlacing */
704#define PNG_INTERLACE_LAST 2 /* Not a valid value */
705
706/* These are for the oFFs chunk. These values should NOT be changed. */
707#define PNG_OFFSET_PIXEL 0 /* Offset in pixels */
708#define PNG_OFFSET_MICROMETER 1 /* Offset in micrometers (1/10^6 meter) */
709#define PNG_OFFSET_LAST 2 /* Not a valid value */
710
711/* These are for the pCAL chunk. These values should NOT be changed. */
712#define PNG_EQUATION_LINEAR 0 /* Linear transformation */
713#define PNG_EQUATION_BASE_E 1 /* Exponential base e transform */
714#define PNG_EQUATION_ARBITRARY 2 /* Arbitrary base exponential transform */
715#define PNG_EQUATION_HYPERBOLIC 3 /* Hyperbolic sine transformation */
716#define PNG_EQUATION_LAST 4 /* Not a valid value */
717
718/* These are for the sCAL chunk. These values should NOT be changed. */
719#define PNG_SCALE_UNKNOWN 0 /* unknown unit (image scale) */
720#define PNG_SCALE_METER 1 /* meters per pixel */
721#define PNG_SCALE_RADIAN 2 /* radians per pixel */
722#define PNG_SCALE_LAST 3 /* Not a valid value */
723
724/* These are for the pHYs chunk. These values should NOT be changed. */
725#define PNG_RESOLUTION_UNKNOWN 0 /* pixels/unknown unit (aspect ratio) */
726#define PNG_RESOLUTION_METER 1 /* pixels/meter */
727#define PNG_RESOLUTION_LAST 2 /* Not a valid value */
728
729/* These are for the sRGB chunk. These values should NOT be changed. */
730#define PNG_sRGB_INTENT_PERCEPTUAL 0
731#define PNG_sRGB_INTENT_RELATIVE 1
732#define PNG_sRGB_INTENT_SATURATION 2
733#define PNG_sRGB_INTENT_ABSOLUTE 3
734#define PNG_sRGB_INTENT_LAST 4 /* Not a valid value */
735
736/* This is for text chunks */
737#define PNG_KEYWORD_MAX_LENGTH 79
738
739/* Maximum number of entries in PLTE/sPLT/tRNS arrays */
740#define PNG_MAX_PALETTE_LENGTH 256
741
742/* These determine if an ancillary chunk's data has been successfully read
743 * from the PNG header, or if the application has filled in the corresponding
744 * data in the info_struct to be written into the output file. The values
745 * of the PNG_INFO_<chunk> defines should NOT be changed.
746 */
747#define PNG_INFO_gAMA 0x0001U
748#define PNG_INFO_sBIT 0x0002U
749#define PNG_INFO_cHRM 0x0004U
750#define PNG_INFO_PLTE 0x0008U
751#define PNG_INFO_tRNS 0x0010U
752#define PNG_INFO_bKGD 0x0020U
753#define PNG_INFO_hIST 0x0040U
754#define PNG_INFO_pHYs 0x0080U
755#define PNG_INFO_oFFs 0x0100U
756#define PNG_INFO_tIME 0x0200U
757#define PNG_INFO_pCAL 0x0400U
758#define PNG_INFO_sRGB 0x0800U /* GR-P, 0.96a */
759#define PNG_INFO_iCCP 0x1000U /* ESR, 1.0.6 */
760#define PNG_INFO_sPLT 0x2000U /* ESR, 1.0.6 */
761#define PNG_INFO_sCAL 0x4000U /* ESR, 1.0.6 */
762#define PNG_INFO_IDAT 0x8000U /* ESR, 1.0.6 */
763#define PNG_INFO_eXIf 0x10000U /* GR-P, 1.6.31 */
764#ifdef PNG_APNG_SUPPORTED
765#define PNG_INFO_acTL 0x20000U
766#define PNG_INFO_fcTL 0x40000U
767#endif
768
769/* This is used for the transformation routines, as some of them
770 * change these values for the row. It also should enable using
771 * the routines for other purposes.
772 */
773typedef struct png_row_info_struct
774{
775 png_uint_32 width; /* width of row */
776 size_t rowbytes; /* number of bytes in row */
777 png_byte color_type; /* color type of row */
778 png_byte bit_depth; /* bit depth of row */
779 png_byte channels; /* number of channels (1, 2, 3, or 4) */
780 png_byte pixel_depth; /* bits per pixel (depth * channels) */
781} png_row_info;
782
783typedef png_row_info * png_row_infop;
784typedef png_row_info * * png_row_infopp;
785
786/* These are the function types for the I/O functions and for the functions
787 * that allow the user to override the default I/O functions with his or her
788 * own. The png_error_ptr type should match that of user-supplied warning
789 * and error functions, while the png_rw_ptr type should match that of the
790 * user read/write data functions. Note that the 'write' function must not
791 * modify the buffer it is passed. The 'read' function, on the other hand, is
792 * expected to return the read data in the buffer.
793 */
794typedef PNG_CALLBACK(void, *png_error_ptr, (png_structp, png_const_charp));
795typedef PNG_CALLBACK(void, *png_rw_ptr, (png_structp, png_bytep, size_t));
796typedef PNG_CALLBACK(void, *png_flush_ptr, (png_structp));
797typedef PNG_CALLBACK(void, *png_read_status_ptr, (png_structp, png_uint_32,
798 int));
799typedef PNG_CALLBACK(void, *png_write_status_ptr, (png_structp, png_uint_32,
800 int));
801
802#ifdef PNG_PROGRESSIVE_READ_SUPPORTED
803typedef PNG_CALLBACK(void, *png_progressive_info_ptr, (png_structp, png_infop));
804typedef PNG_CALLBACK(void, *png_progressive_end_ptr, (png_structp, png_infop));
805#ifdef PNG_APNG_SUPPORTED
806typedef PNG_CALLBACK(void, *png_progressive_frame_ptr, (png_structp,
807 png_uint_32));
808#endif
809
810/* The following callback receives png_uint_32 row_number, int pass for the
811 * png_bytep data of the row. When transforming an interlaced image the
812 * row number is the row number within the sub-image of the interlace pass, so
813 * the value will increase to the height of the sub-image (not the full image)
814 * then reset to 0 for the next pass.
815 *
816 * Use PNG_ROW_FROM_PASS_ROW(row, pass) and PNG_COL_FROM_PASS_COL(col, pass) to
817 * find the output pixel (x,y) given an interlaced sub-image pixel
818 * (row,col,pass). (See below for these macros.)
819 */
820typedef PNG_CALLBACK(void, *png_progressive_row_ptr, (png_structp, png_bytep,
821 png_uint_32, int));
822#endif
823
824#if defined(PNG_READ_USER_TRANSFORM_SUPPORTED) || \
825 defined(PNG_WRITE_USER_TRANSFORM_SUPPORTED)
826typedef PNG_CALLBACK(void, *png_user_transform_ptr, (png_structp, png_row_infop,
827 png_bytep));
828#endif
829
830#ifdef PNG_USER_CHUNKS_SUPPORTED
831typedef PNG_CALLBACK(int, *png_user_chunk_ptr, (png_structp,
832 png_unknown_chunkp));
833#endif
834#ifdef PNG_UNKNOWN_CHUNKS_SUPPORTED
835/* not used anywhere */
836/* typedef PNG_CALLBACK(void, *png_unknown_chunk_ptr, (png_structp)); */
837#endif
838
839#ifdef PNG_SETJMP_SUPPORTED
840/* This must match the function definition in <setjmp.h>, and the application
841 * must include this before png.h to obtain the definition of jmp_buf. The
842 * function is required to be PNG_NORETURN, but this is not checked. If the
843 * function does return the application will crash via an abort() or similar
844 * system level call.
845 *
846 * If you get a warning here while building the library you may need to make
847 * changes to ensure that pnglibconf.h records the calling convention used by
848 * your compiler. This may be very difficult - try using a different compiler
849 * to build the library!
850 */
851PNG_FUNCTION(void, (PNGCAPI *png_longjmp_ptr), PNGARG((jmp_buf, int)), typedef);
852#endif
853
854/* Transform masks for the high-level interface */
855#define PNG_TRANSFORM_IDENTITY 0x0000 /* read and write */
856#define PNG_TRANSFORM_STRIP_16 0x0001 /* read only */
857#define PNG_TRANSFORM_STRIP_ALPHA 0x0002 /* read only */
858#define PNG_TRANSFORM_PACKING 0x0004 /* read and write */
859#define PNG_TRANSFORM_PACKSWAP 0x0008 /* read and write */
860#define PNG_TRANSFORM_EXPAND 0x0010 /* read only */
861#define PNG_TRANSFORM_INVERT_MONO 0x0020 /* read and write */
862#define PNG_TRANSFORM_SHIFT 0x0040 /* read and write */
863#define PNG_TRANSFORM_BGR 0x0080 /* read and write */
864#define PNG_TRANSFORM_SWAP_ALPHA 0x0100 /* read and write */
865#define PNG_TRANSFORM_SWAP_ENDIAN 0x0200 /* read and write */
866#define PNG_TRANSFORM_INVERT_ALPHA 0x0400 /* read and write */
867#define PNG_TRANSFORM_STRIP_FILLER 0x0800 /* write only */
868/* Added to libpng-1.2.34 */
869#define PNG_TRANSFORM_STRIP_FILLER_BEFORE PNG_TRANSFORM_STRIP_FILLER
870#define PNG_TRANSFORM_STRIP_FILLER_AFTER 0x1000 /* write only */
871/* Added to libpng-1.4.0 */
872#define PNG_TRANSFORM_GRAY_TO_RGB 0x2000 /* read only */
873/* Added to libpng-1.5.4 */
874#define PNG_TRANSFORM_EXPAND_16 0x4000 /* read only */
875#if INT_MAX >= 0x8000 /* else this might break */
876#define PNG_TRANSFORM_SCALE_16 0x8000 /* read only */
877#endif
878
879/* Flags for MNG supported features */
880#define PNG_FLAG_MNG_EMPTY_PLTE 0x01
881#define PNG_FLAG_MNG_FILTER_64 0x04
882#define PNG_ALL_MNG_FEATURES 0x05
883
884/* NOTE: prior to 1.5 these functions had no 'API' style declaration,
885 * this allowed the zlib default functions to be used on Windows
886 * platforms. In 1.5 the zlib default malloc (which just calls malloc and
887 * ignores the first argument) should be completely compatible with the
888 * following.
889 */
890typedef PNG_CALLBACK(png_voidp, *png_malloc_ptr, (png_structp,
891 png_alloc_size_t));
892typedef PNG_CALLBACK(void, *png_free_ptr, (png_structp, png_voidp));
893
894/* Section 4: exported functions
895 * Here are the function definitions most commonly used. This is not
896 * the place to find out how to use libpng. See libpng-manual.txt for the
897 * full explanation, see example.c for the summary. This just provides
898 * a simple one line description of the use of each function.
899 *
900 * The PNG_EXPORT() and PNG_EXPORTA() macros used below are defined in
901 * pngconf.h and in the *.dfn files in the scripts directory.
902 *
903 * PNG_EXPORT(ordinal, type, name, (args));
904 *
905 * ordinal: ordinal that is used while building
906 * *.def files. The ordinal value is only
907 * relevant when preprocessing png.h with
908 * the *.dfn files for building symbol table
909 * entries, and are removed by pngconf.h.
910 * type: return type of the function
911 * name: function name
912 * args: function arguments, with types
913 *
914 * When we wish to append attributes to a function prototype we use
915 * the PNG_EXPORTA() macro instead.
916 *
917 * PNG_EXPORTA(ordinal, type, name, (args), attributes);
918 *
919 * ordinal, type, name, and args: same as in PNG_EXPORT().
920 * attributes: function attributes
921 */
922
923/* Returns the version number of the library */
924PNG_EXPORT(1, png_uint_32, png_access_version_number, (void));
925
926/* Tell lib we have already handled the first <num_bytes> magic bytes.
927 * Handling more than 8 bytes from the beginning of the file is an error.
928 */
929PNG_EXPORT(2, void, png_set_sig_bytes, (png_structrp png_ptr, int num_bytes));
930
931/* Check sig[start] through sig[start + num_to_check - 1] to see if it's a
932 * PNG file. Returns zero if the supplied bytes match the 8-byte PNG
933 * signature, and non-zero otherwise. Having num_to_check == 0 or
934 * start > 7 will always fail (ie return non-zero).
935 */
936PNG_EXPORT(3, int, png_sig_cmp, (png_const_bytep sig, size_t start,
937 size_t num_to_check));
938
939/* Simple signature checking function. This is the same as calling
940 * png_check_sig(sig, n) := !png_sig_cmp(sig, 0, n).
941 */
942#define png_check_sig(sig, n) !png_sig_cmp((sig), 0, (n))
943
944/* Allocate and initialize png_ptr struct for reading, and any other memory. */
945PNG_EXPORTA(4, png_structp, png_create_read_struct,
946 (png_const_charp user_png_ver, png_voidp error_ptr,
947 png_error_ptr error_fn, png_error_ptr warn_fn),
948 PNG_ALLOCATED);
949
950/* Allocate and initialize png_ptr struct for writing, and any other memory */
951PNG_EXPORTA(5, png_structp, png_create_write_struct,
952 (png_const_charp user_png_ver, png_voidp error_ptr, png_error_ptr error_fn,
953 png_error_ptr warn_fn),
954 PNG_ALLOCATED);
955
956PNG_EXPORT(6, size_t, png_get_compression_buffer_size,
957 (png_const_structrp png_ptr));
958
959PNG_EXPORT(7, void, png_set_compression_buffer_size, (png_structrp png_ptr,
960 size_t size));
961
962/* Moved from pngconf.h in 1.4.0 and modified to ensure setjmp/longjmp
963 * match up.
964 */
965#ifdef PNG_SETJMP_SUPPORTED
966/* This function returns the jmp_buf built in to *png_ptr. It must be
967 * supplied with an appropriate 'longjmp' function to use on that jmp_buf
968 * unless the default error function is overridden in which case NULL is
969 * acceptable. The size of the jmp_buf is checked against the actual size
970 * allocated by the library - the call will return NULL on a mismatch
971 * indicating an ABI mismatch.
972 */
973PNG_EXPORT(8, jmp_buf*, png_set_longjmp_fn, (png_structrp png_ptr,
974 png_longjmp_ptr longjmp_fn, size_t jmp_buf_size));
975# define png_jmpbuf(png_ptr) \
976 (*png_set_longjmp_fn((png_ptr), longjmp, (sizeof (jmp_buf))))
977#else
978# define png_jmpbuf(png_ptr) \
979 (LIBPNG_WAS_COMPILED_WITH__PNG_NO_SETJMP)
980#endif
981/* This function should be used by libpng applications in place of
982 * longjmp(png_ptr->jmpbuf, val). If longjmp_fn() has been set, it
983 * will use it; otherwise it will call PNG_ABORT(). This function was
984 * added in libpng-1.5.0.
985 */
986PNG_EXPORTA(9, void, png_longjmp, (png_const_structrp png_ptr, int val),
987 PNG_NORETURN);
988
989#ifdef PNG_READ_SUPPORTED
990/* Reset the compression stream */
991PNG_EXPORTA(10, int, png_reset_zstream, (png_structrp png_ptr), PNG_DEPRECATED);
992#endif
993
994/* New functions added in libpng-1.0.2 (not enabled by default until 1.2.0) */
995#ifdef PNG_USER_MEM_SUPPORTED
996PNG_EXPORTA(11, png_structp, png_create_read_struct_2,
997 (png_const_charp user_png_ver, png_voidp error_ptr, png_error_ptr error_fn,
998 png_error_ptr warn_fn,
999 png_voidp mem_ptr, png_malloc_ptr malloc_fn, png_free_ptr free_fn),
1000 PNG_ALLOCATED);
1001PNG_EXPORTA(12, png_structp, png_create_write_struct_2,
1002 (png_const_charp user_png_ver, png_voidp error_ptr, png_error_ptr error_fn,
1003 png_error_ptr warn_fn,
1004 png_voidp mem_ptr, png_malloc_ptr malloc_fn, png_free_ptr free_fn),
1005 PNG_ALLOCATED);
1006#endif
1007
1008/* Write the PNG file signature. */
1009PNG_EXPORT(13, void, png_write_sig, (png_structrp png_ptr));
1010
1011/* Write a PNG chunk - size, type, (optional) data, CRC. */
1012PNG_EXPORT(14, void, png_write_chunk, (png_structrp png_ptr, png_const_bytep
1013 chunk_name, png_const_bytep data, size_t length));
1014
1015/* Write the start of a PNG chunk - length and chunk name. */
1016PNG_EXPORT(15, void, png_write_chunk_start, (png_structrp png_ptr,
1017 png_const_bytep chunk_name, png_uint_32 length));
1018
1019/* Write the data of a PNG chunk started with png_write_chunk_start(). */
1020PNG_EXPORT(16, void, png_write_chunk_data, (png_structrp png_ptr,
1021 png_const_bytep data, size_t length));
1022
1023/* Finish a chunk started with png_write_chunk_start() (includes CRC). */
1024PNG_EXPORT(17, void, png_write_chunk_end, (png_structrp png_ptr));
1025
1026/* Allocate and initialize the info structure */
1027PNG_EXPORTA(18, png_infop, png_create_info_struct, (png_const_structrp png_ptr),
1028 PNG_ALLOCATED);
1029
1030/* DEPRECATED: this function allowed init structures to be created using the
1031 * default allocation method (typically malloc). Use is deprecated in 1.6.0 and
1032 * the API will be removed in the future.
1033 */
1034PNG_EXPORTA(19, void, png_info_init_3, (png_infopp info_ptr,
1035 size_t png_info_struct_size), PNG_DEPRECATED);
1036
1037/* Writes all the PNG information before the image. */
1038PNG_EXPORT(20, void, png_write_info_before_PLTE,
1039 (png_structrp png_ptr, png_const_inforp info_ptr));
1040PNG_EXPORT(21, void, png_write_info,
1041 (png_structrp png_ptr, png_const_inforp info_ptr));
1042
1043#ifdef PNG_SEQUENTIAL_READ_SUPPORTED
1044/* Read the information before the actual image data. */
1045PNG_EXPORT(22, void, png_read_info,
1046 (png_structrp png_ptr, png_inforp info_ptr));
1047#endif
1048
1049#ifdef PNG_TIME_RFC1123_SUPPORTED
1050 /* Convert to a US string format: there is no localization support in this
1051 * routine. The original implementation used a 29 character buffer in
1052 * png_struct, this will be removed in future versions.
1053 */
1054#if PNG_LIBPNG_VER < 10700
1055/* To do: remove this from libpng17 (and from libpng17/png.c and pngstruct.h) */
1056PNG_EXPORTA(23, png_const_charp, png_convert_to_rfc1123, (png_structrp png_ptr,
1057 png_const_timep ptime),PNG_DEPRECATED);
1058#endif
1059PNG_EXPORT(241, int, png_convert_to_rfc1123_buffer, (char out[29],
1060 png_const_timep ptime));
1061#endif
1062
1063#ifdef PNG_CONVERT_tIME_SUPPORTED
1064/* Convert from a struct tm to png_time */
1065PNG_EXPORT(24, void, png_convert_from_struct_tm, (png_timep ptime,
1066 const struct tm * ttime));
1067
1068/* Convert from time_t to png_time. Uses gmtime() */
1069PNG_EXPORT(25, void, png_convert_from_time_t, (png_timep ptime, time_t ttime));
1070#endif /* CONVERT_tIME */
1071
1072#ifdef PNG_READ_EXPAND_SUPPORTED
1073/* Expand data to 24-bit RGB, or 8-bit grayscale, with alpha if available. */
1074PNG_EXPORT(26, void, png_set_expand, (png_structrp png_ptr));
1075PNG_EXPORT(27, void, png_set_expand_gray_1_2_4_to_8, (png_structrp png_ptr));
1076PNG_EXPORT(28, void, png_set_palette_to_rgb, (png_structrp png_ptr));
1077PNG_EXPORT(29, void, png_set_tRNS_to_alpha, (png_structrp png_ptr));
1078#endif
1079
1080#ifdef PNG_READ_EXPAND_16_SUPPORTED
1081/* Expand to 16-bit channels, forces conversion of palette to RGB and expansion
1082 * of a tRNS chunk if present.
1083 */
1084PNG_EXPORT(221, void, png_set_expand_16, (png_structrp png_ptr));
1085#endif
1086
1087#if defined(PNG_READ_BGR_SUPPORTED) || defined(PNG_WRITE_BGR_SUPPORTED)
1088/* Use blue, green, red order for pixels. */
1089PNG_EXPORT(30, void, png_set_bgr, (png_structrp png_ptr));
1090#endif
1091
1092#ifdef PNG_READ_GRAY_TO_RGB_SUPPORTED
1093/* Expand the grayscale to 24-bit RGB if necessary. */
1094PNG_EXPORT(31, void, png_set_gray_to_rgb, (png_structrp png_ptr));
1095#endif
1096
1097#ifdef PNG_READ_RGB_TO_GRAY_SUPPORTED
1098/* Reduce RGB to grayscale. */
1099#define PNG_ERROR_ACTION_NONE 1
1100#define PNG_ERROR_ACTION_WARN 2
1101#define PNG_ERROR_ACTION_ERROR 3
1102#define PNG_RGB_TO_GRAY_DEFAULT (-1)/*for red/green coefficients*/
1103
1104PNG_FP_EXPORT(32, void, png_set_rgb_to_gray, (png_structrp png_ptr,
1105 int error_action, double red, double green))
1106PNG_FIXED_EXPORT(33, void, png_set_rgb_to_gray_fixed, (png_structrp png_ptr,
1107 int error_action, png_fixed_point red, png_fixed_point green))
1108
1109PNG_EXPORT(34, png_byte, png_get_rgb_to_gray_status, (png_const_structrp
1110 png_ptr));
1111#endif
1112
1113#ifdef PNG_BUILD_GRAYSCALE_PALETTE_SUPPORTED
1114PNG_EXPORT(35, void, png_build_grayscale_palette, (int bit_depth,
1115 png_colorp palette));
1116#endif
1117
1118#ifdef PNG_READ_ALPHA_MODE_SUPPORTED
1119/* How the alpha channel is interpreted - this affects how the color channels
1120 * of a PNG file are returned to the calling application when an alpha channel,
1121 * or a tRNS chunk in a palette file, is present.
1122 *
1123 * This has no effect on the way pixels are written into a PNG output
1124 * datastream. The color samples in a PNG datastream are never premultiplied
1125 * with the alpha samples.
1126 *
1127 * The default is to return data according to the PNG specification: the alpha
1128 * channel is a linear measure of the contribution of the pixel to the
1129 * corresponding composited pixel, and the color channels are unassociated
1130 * (not premultiplied). The gamma encoded color channels must be scaled
1131 * according to the contribution and to do this it is necessary to undo
1132 * the encoding, scale the color values, perform the composition and re-encode
1133 * the values. This is the 'PNG' mode.
1134 *
1135 * The alternative is to 'associate' the alpha with the color information by
1136 * storing color channel values that have been scaled by the alpha.
1137 * image. These are the 'STANDARD', 'ASSOCIATED' or 'PREMULTIPLIED' modes
1138 * (the latter being the two common names for associated alpha color channels).
1139 *
1140 * For the 'OPTIMIZED' mode, a pixel is treated as opaque only if the alpha
1141 * value is equal to the maximum value.
1142 *
1143 * The final choice is to gamma encode the alpha channel as well. This is
1144 * broken because, in practice, no implementation that uses this choice
1145 * correctly undoes the encoding before handling alpha composition. Use this
1146 * choice only if other serious errors in the software or hardware you use
1147 * mandate it; the typical serious error is for dark halos to appear around
1148 * opaque areas of the composited PNG image because of arithmetic overflow.
1149 *
1150 * The API function png_set_alpha_mode specifies which of these choices to use
1151 * with an enumerated 'mode' value and the gamma of the required output:
1152 */
1153#define PNG_ALPHA_PNG 0 /* according to the PNG standard */
1154#define PNG_ALPHA_STANDARD 1 /* according to Porter/Duff */
1155#define PNG_ALPHA_ASSOCIATED 1 /* as above; this is the normal practice */
1156#define PNG_ALPHA_PREMULTIPLIED 1 /* as above */
1157#define PNG_ALPHA_OPTIMIZED 2 /* 'PNG' for opaque pixels, else 'STANDARD' */
1158#define PNG_ALPHA_BROKEN 3 /* the alpha channel is gamma encoded */
1159
1160PNG_FP_EXPORT(227, void, png_set_alpha_mode, (png_structrp png_ptr, int mode,
1161 double output_gamma))
1162PNG_FIXED_EXPORT(228, void, png_set_alpha_mode_fixed, (png_structrp png_ptr,
1163 int mode, png_fixed_point output_gamma))
1164#endif
1165
1166#if defined(PNG_GAMMA_SUPPORTED) || defined(PNG_READ_ALPHA_MODE_SUPPORTED)
1167/* The output_gamma value is a screen gamma in libpng terminology: it expresses
1168 * how to decode the output values, not how they are encoded.
1169 */
1170#define PNG_DEFAULT_sRGB -1 /* sRGB gamma and color space */
1171#define PNG_GAMMA_MAC_18 -2 /* Old Mac '1.8' gamma and color space */
1172#define PNG_GAMMA_sRGB 220000 /* Television standards--matches sRGB gamma */
1173#define PNG_GAMMA_LINEAR PNG_FP_1 /* Linear */
1174#endif
1175
1176/* The following are examples of calls to png_set_alpha_mode to achieve the
1177 * required overall gamma correction and, where necessary, alpha
1178 * premultiplication.
1179 *
1180 * png_set_alpha_mode(pp, PNG_ALPHA_PNG, PNG_DEFAULT_sRGB);
1181 * This is the default libpng handling of the alpha channel - it is not
1182 * pre-multiplied into the color components. In addition the call states
1183 * that the output is for a sRGB system and causes all PNG files without gAMA
1184 * chunks to be assumed to be encoded using sRGB.
1185 *
1186 * png_set_alpha_mode(pp, PNG_ALPHA_PNG, PNG_GAMMA_MAC);
1187 * In this case the output is assumed to be something like an sRGB conformant
1188 * display preceded by a power-law lookup table of power 1.45. This is how
1189 * early Mac systems behaved.
1190 *
1191 * png_set_alpha_mode(pp, PNG_ALPHA_STANDARD, PNG_GAMMA_LINEAR);
1192 * This is the classic Jim Blinn approach and will work in academic
1193 * environments where everything is done by the book. It has the shortcoming
1194 * of assuming that input PNG data with no gamma information is linear - this
1195 * is unlikely to be correct unless the PNG files where generated locally.
1196 * Most of the time the output precision will be so low as to show
1197 * significant banding in dark areas of the image.
1198 *
1199 * png_set_expand_16(pp);
1200 * png_set_alpha_mode(pp, PNG_ALPHA_STANDARD, PNG_DEFAULT_sRGB);
1201 * This is a somewhat more realistic Jim Blinn inspired approach. PNG files
1202 * are assumed to have the sRGB encoding if not marked with a gamma value and
1203 * the output is always 16 bits per component. This permits accurate scaling
1204 * and processing of the data. If you know that your input PNG files were
1205 * generated locally you might need to replace PNG_DEFAULT_sRGB with the
1206 * correct value for your system.
1207 *
1208 * png_set_alpha_mode(pp, PNG_ALPHA_OPTIMIZED, PNG_DEFAULT_sRGB);
1209 * If you just need to composite the PNG image onto an existing background
1210 * and if you control the code that does this you can use the optimization
1211 * setting. In this case you just copy completely opaque pixels to the
1212 * output. For pixels that are not completely transparent (you just skip
1213 * those) you do the composition math using png_composite or png_composite_16
1214 * below then encode the resultant 8-bit or 16-bit values to match the output
1215 * encoding.
1216 *
1217 * Other cases
1218 * If neither the PNG nor the standard linear encoding work for you because
1219 * of the software or hardware you use then you have a big problem. The PNG
1220 * case will probably result in halos around the image. The linear encoding
1221 * will probably result in a washed out, too bright, image (it's actually too
1222 * contrasty.) Try the ALPHA_OPTIMIZED mode above - this will probably
1223 * substantially reduce the halos. Alternatively try:
1224 *
1225 * png_set_alpha_mode(pp, PNG_ALPHA_BROKEN, PNG_DEFAULT_sRGB);
1226 * This option will also reduce the halos, but there will be slight dark
1227 * halos round the opaque parts of the image where the background is light.
1228 * In the OPTIMIZED mode the halos will be light halos where the background
1229 * is dark. Take your pick - the halos are unavoidable unless you can get
1230 * your hardware/software fixed! (The OPTIMIZED approach is slightly
1231 * faster.)
1232 *
1233 * When the default gamma of PNG files doesn't match the output gamma.
1234 * If you have PNG files with no gamma information png_set_alpha_mode allows
1235 * you to provide a default gamma, but it also sets the output gamma to the
1236 * matching value. If you know your PNG files have a gamma that doesn't
1237 * match the output you can take advantage of the fact that
1238 * png_set_alpha_mode always sets the output gamma but only sets the PNG
1239 * default if it is not already set:
1240 *
1241 * png_set_alpha_mode(pp, PNG_ALPHA_PNG, PNG_DEFAULT_sRGB);
1242 * png_set_alpha_mode(pp, PNG_ALPHA_PNG, PNG_GAMMA_MAC);
1243 * The first call sets both the default and the output gamma values, the
1244 * second call overrides the output gamma without changing the default. This
1245 * is easier than achieving the same effect with png_set_gamma. You must use
1246 * PNG_ALPHA_PNG for the first call - internal checking in png_set_alpha will
1247 * fire if more than one call to png_set_alpha_mode and png_set_background is
1248 * made in the same read operation, however multiple calls with PNG_ALPHA_PNG
1249 * are ignored.
1250 */
1251
1252#ifdef PNG_READ_STRIP_ALPHA_SUPPORTED
1253PNG_EXPORT(36, void, png_set_strip_alpha, (png_structrp png_ptr));
1254#endif
1255
1256#if defined(PNG_READ_SWAP_ALPHA_SUPPORTED) || \
1257 defined(PNG_WRITE_SWAP_ALPHA_SUPPORTED)
1258PNG_EXPORT(37, void, png_set_swap_alpha, (png_structrp png_ptr));
1259#endif
1260
1261#if defined(PNG_READ_INVERT_ALPHA_SUPPORTED) || \
1262 defined(PNG_WRITE_INVERT_ALPHA_SUPPORTED)
1263PNG_EXPORT(38, void, png_set_invert_alpha, (png_structrp png_ptr));
1264#endif
1265
1266#if defined(PNG_READ_FILLER_SUPPORTED) || defined(PNG_WRITE_FILLER_SUPPORTED)
1267/* Add a filler byte to 8-bit or 16-bit Gray or 24-bit or 48-bit RGB images. */
1268PNG_EXPORT(39, void, png_set_filler, (png_structrp png_ptr, png_uint_32 filler,
1269 int flags));
1270/* The values of the PNG_FILLER_ defines should NOT be changed */
1271# define PNG_FILLER_BEFORE 0
1272# define PNG_FILLER_AFTER 1
1273/* Add an alpha byte to 8-bit or 16-bit Gray or 24-bit or 48-bit RGB images. */
1274PNG_EXPORT(40, void, png_set_add_alpha, (png_structrp png_ptr,
1275 png_uint_32 filler, int flags));
1276#endif /* READ_FILLER || WRITE_FILLER */
1277
1278#if defined(PNG_READ_SWAP_SUPPORTED) || defined(PNG_WRITE_SWAP_SUPPORTED)
1279/* Swap bytes in 16-bit depth files. */
1280PNG_EXPORT(41, void, png_set_swap, (png_structrp png_ptr));
1281#endif
1282
1283#if defined(PNG_READ_PACK_SUPPORTED) || defined(PNG_WRITE_PACK_SUPPORTED)
1284/* Use 1 byte per pixel in 1, 2, or 4-bit depth files. */
1285PNG_EXPORT(42, void, png_set_packing, (png_structrp png_ptr));
1286#endif
1287
1288#if defined(PNG_READ_PACKSWAP_SUPPORTED) || \
1289 defined(PNG_WRITE_PACKSWAP_SUPPORTED)
1290/* Swap packing order of pixels in bytes. */
1291PNG_EXPORT(43, void, png_set_packswap, (png_structrp png_ptr));
1292#endif
1293
1294#if defined(PNG_READ_SHIFT_SUPPORTED) || defined(PNG_WRITE_SHIFT_SUPPORTED)
1295/* Converts files to legal bit depths. */
1296PNG_EXPORT(44, void, png_set_shift, (png_structrp png_ptr, png_const_color_8p
1297 true_bits));
1298#endif
1299
1300#if defined(PNG_READ_INTERLACING_SUPPORTED) || \
1301 defined(PNG_WRITE_INTERLACING_SUPPORTED)
1302/* Have the code handle the interlacing. Returns the number of passes.
1303 * MUST be called before png_read_update_info or png_start_read_image,
1304 * otherwise it will not have the desired effect. Note that it is still
1305 * necessary to call png_read_row or png_read_rows png_get_image_height
1306 * times for each pass.
1307*/
1308PNG_EXPORT(45, int, png_set_interlace_handling, (png_structrp png_ptr));
1309#endif
1310
1311#if defined(PNG_READ_INVERT_SUPPORTED) || defined(PNG_WRITE_INVERT_SUPPORTED)
1312/* Invert monochrome files */
1313PNG_EXPORT(46, void, png_set_invert_mono, (png_structrp png_ptr));
1314#endif
1315
1316#ifdef PNG_READ_BACKGROUND_SUPPORTED
1317/* Handle alpha and tRNS by replacing with a background color. Prior to
1318 * libpng-1.5.4 this API must not be called before the PNG file header has been
1319 * read. Doing so will result in unexpected behavior and possible warnings or
1320 * errors if the PNG file contains a bKGD chunk.
1321 */
1322PNG_FP_EXPORT(47, void, png_set_background, (png_structrp png_ptr,
1323 png_const_color_16p background_color, int background_gamma_code,
1324 int need_expand, double background_gamma))
1325PNG_FIXED_EXPORT(215, void, png_set_background_fixed, (png_structrp png_ptr,
1326 png_const_color_16p background_color, int background_gamma_code,
1327 int need_expand, png_fixed_point background_gamma))
1328#endif
1329#ifdef PNG_READ_BACKGROUND_SUPPORTED
1330# define PNG_BACKGROUND_GAMMA_UNKNOWN 0
1331# define PNG_BACKGROUND_GAMMA_SCREEN 1
1332# define PNG_BACKGROUND_GAMMA_FILE 2
1333# define PNG_BACKGROUND_GAMMA_UNIQUE 3
1334#endif
1335
1336#ifdef PNG_READ_SCALE_16_TO_8_SUPPORTED
1337/* Scale a 16-bit depth file down to 8-bit, accurately. */
1338PNG_EXPORT(229, void, png_set_scale_16, (png_structrp png_ptr));
1339#endif
1340
1341#ifdef PNG_READ_STRIP_16_TO_8_SUPPORTED
1342#define PNG_READ_16_TO_8_SUPPORTED /* Name prior to 1.5.4 */
1343/* Strip the second byte of information from a 16-bit depth file. */
1344PNG_EXPORT(48, void, png_set_strip_16, (png_structrp png_ptr));
1345#endif
1346
1347#ifdef PNG_READ_QUANTIZE_SUPPORTED
1348/* Turn on quantizing, and reduce the palette to the number of colors
1349 * available.
1350 */
1351PNG_EXPORT(49, void, png_set_quantize, (png_structrp png_ptr,
1352 png_colorp palette, int num_palette, int maximum_colors,
1353 png_const_uint_16p histogram, int full_quantize));
1354#endif
1355
1356#ifdef PNG_READ_GAMMA_SUPPORTED
1357/* The threshold on gamma processing is configurable but hard-wired into the
1358 * library. The following is the floating point variant.
1359 */
1360#define PNG_GAMMA_THRESHOLD (PNG_GAMMA_THRESHOLD_FIXED*.00001)
1361
1362/* Handle gamma correction. Screen_gamma=(display_exponent).
1363 * NOTE: this API simply sets the screen and file gamma values. It will
1364 * therefore override the value for gamma in a PNG file if it is called after
1365 * the file header has been read - use with care - call before reading the PNG
1366 * file for best results!
1367 *
1368 * These routines accept the same gamma values as png_set_alpha_mode (described
1369 * above). The PNG_GAMMA_ defines and PNG_DEFAULT_sRGB can be passed to either
1370 * API (floating point or fixed.) Notice, however, that the 'file_gamma' value
1371 * is the inverse of a 'screen gamma' value.
1372 */
1373PNG_FP_EXPORT(50, void, png_set_gamma, (png_structrp png_ptr,
1374 double screen_gamma, double override_file_gamma))
1375PNG_FIXED_EXPORT(208, void, png_set_gamma_fixed, (png_structrp png_ptr,
1376 png_fixed_point screen_gamma, png_fixed_point override_file_gamma))
1377#endif
1378
1379#ifdef PNG_WRITE_FLUSH_SUPPORTED
1380/* Set how many lines between output flushes - 0 for no flushing */
1381PNG_EXPORT(51, void, png_set_flush, (png_structrp png_ptr, int nrows));
1382/* Flush the current PNG output buffer */
1383PNG_EXPORT(52, void, png_write_flush, (png_structrp png_ptr));
1384#endif
1385
1386/* Optional update palette with requested transformations */
1387PNG_EXPORT(53, void, png_start_read_image, (png_structrp png_ptr));
1388
1389/* Optional call to update the users info structure */
1390PNG_EXPORT(54, void, png_read_update_info, (png_structrp png_ptr,
1391 png_inforp info_ptr));
1392
1393#ifdef PNG_SEQUENTIAL_READ_SUPPORTED
1394/* Read one or more rows of image data. */
1395PNG_EXPORT(55, void, png_read_rows, (png_structrp png_ptr, png_bytepp row,
1396 png_bytepp display_row, png_uint_32 num_rows));
1397#endif
1398
1399#ifdef PNG_SEQUENTIAL_READ_SUPPORTED
1400/* Read a row of data. */
1401PNG_EXPORT(56, void, png_read_row, (png_structrp png_ptr, png_bytep row,
1402 png_bytep display_row));
1403#endif
1404
1405#ifdef PNG_SEQUENTIAL_READ_SUPPORTED
1406/* Read the whole image into memory at once. */
1407PNG_EXPORT(57, void, png_read_image, (png_structrp png_ptr, png_bytepp image));
1408#endif
1409
1410/* Write a row of image data */
1411PNG_EXPORT(58, void, png_write_row, (png_structrp png_ptr,
1412 png_const_bytep row));
1413
1414/* Write a few rows of image data: (*row) is not written; however, the type
1415 * is declared as writeable to maintain compatibility with previous versions
1416 * of libpng and to allow the 'display_row' array from read_rows to be passed
1417 * unchanged to write_rows.
1418 */
1419PNG_EXPORT(59, void, png_write_rows, (png_structrp png_ptr, png_bytepp row,
1420 png_uint_32 num_rows));
1421
1422/* Write the image data */
1423PNG_EXPORT(60, void, png_write_image, (png_structrp png_ptr, png_bytepp image));
1424
1425/* Write the end of the PNG file. */
1426PNG_EXPORT(61, void, png_write_end, (png_structrp png_ptr,
1427 png_inforp info_ptr));
1428
1429#ifdef PNG_SEQUENTIAL_READ_SUPPORTED
1430/* Read the end of the PNG file. */
1431PNG_EXPORT(62, void, png_read_end, (png_structrp png_ptr, png_inforp info_ptr));
1432#endif
1433
1434/* Free any memory associated with the png_info_struct */
1435PNG_EXPORT(63, void, png_destroy_info_struct, (png_const_structrp png_ptr,
1436 png_infopp info_ptr_ptr));
1437
1438/* Free any memory associated with the png_struct and the png_info_structs */
1439PNG_EXPORT(64, void, png_destroy_read_struct, (png_structpp png_ptr_ptr,
1440 png_infopp info_ptr_ptr, png_infopp end_info_ptr_ptr));
1441
1442/* Free any memory associated with the png_struct and the png_info_structs */
1443PNG_EXPORT(65, void, png_destroy_write_struct, (png_structpp png_ptr_ptr,
1444 png_infopp info_ptr_ptr));
1445
1446/* Set the libpng method of handling chunk CRC errors */
1447PNG_EXPORT(66, void, png_set_crc_action, (png_structrp png_ptr, int crit_action,
1448 int ancil_action));
1449
1450/* Values for png_set_crc_action() say how to handle CRC errors in
1451 * ancillary and critical chunks, and whether to use the data contained
1452 * therein. Note that it is impossible to "discard" data in a critical
1453 * chunk. For versions prior to 0.90, the action was always error/quit,
1454 * whereas in version 0.90 and later, the action for CRC errors in ancillary
1455 * chunks is warn/discard. These values should NOT be changed.
1456 *
1457 * value action:critical action:ancillary
1458 */
1459#define PNG_CRC_DEFAULT 0 /* error/quit warn/discard data */
1460#define PNG_CRC_ERROR_QUIT 1 /* error/quit error/quit */
1461#define PNG_CRC_WARN_DISCARD 2 /* (INVALID) warn/discard data */
1462#define PNG_CRC_WARN_USE 3 /* warn/use data warn/use data */
1463#define PNG_CRC_QUIET_USE 4 /* quiet/use data quiet/use data */
1464#define PNG_CRC_NO_CHANGE 5 /* use current value use current value */
1465
1466#ifdef PNG_WRITE_SUPPORTED
1467/* These functions give the user control over the scan-line filtering in
1468 * libpng and the compression methods used by zlib. These functions are
1469 * mainly useful for testing, as the defaults should work with most users.
1470 * Those users who are tight on memory or want faster performance at the
1471 * expense of compression can modify them. See the compression library
1472 * header file (zlib.h) for an explination of the compression functions.
1473 */
1474
1475/* Set the filtering method(s) used by libpng. Currently, the only valid
1476 * value for "method" is 0.
1477 */
1478PNG_EXPORT(67, void, png_set_filter, (png_structrp png_ptr, int method,
1479 int filters));
1480#endif /* WRITE */
1481
1482/* Flags for png_set_filter() to say which filters to use. The flags
1483 * are chosen so that they don't conflict with real filter types
1484 * below, in case they are supplied instead of the #defined constants.
1485 * These values should NOT be changed.
1486 */
1487#define PNG_NO_FILTERS 0x00
1488#define PNG_FILTER_NONE 0x08
1489#define PNG_FILTER_SUB 0x10
1490#define PNG_FILTER_UP 0x20
1491#define PNG_FILTER_AVG 0x40
1492#define PNG_FILTER_PAETH 0x80
1493#define PNG_FAST_FILTERS (PNG_FILTER_NONE | PNG_FILTER_SUB | PNG_FILTER_UP)
1494#define PNG_ALL_FILTERS (PNG_FAST_FILTERS | PNG_FILTER_AVG | PNG_FILTER_PAETH)
1495
1496/* Filter values (not flags) - used in pngwrite.c, pngwutil.c for now.
1497 * These defines should NOT be changed.
1498 */
1499#define PNG_FILTER_VALUE_NONE 0
1500#define PNG_FILTER_VALUE_SUB 1
1501#define PNG_FILTER_VALUE_UP 2
1502#define PNG_FILTER_VALUE_AVG 3
1503#define PNG_FILTER_VALUE_PAETH 4
1504#define PNG_FILTER_VALUE_LAST 5
1505
1506#ifdef PNG_WRITE_SUPPORTED
1507#ifdef PNG_WRITE_WEIGHTED_FILTER_SUPPORTED /* DEPRECATED */
1508PNG_FP_EXPORT(68, void, png_set_filter_heuristics, (png_structrp png_ptr,
1509 int heuristic_method, int num_weights, png_const_doublep filter_weights,
1510 png_const_doublep filter_costs))
1511PNG_FIXED_EXPORT(209, void, png_set_filter_heuristics_fixed,
1512 (png_structrp png_ptr, int heuristic_method, int num_weights,
1513 png_const_fixed_point_p filter_weights,
1514 png_const_fixed_point_p filter_costs))
1515#endif /* WRITE_WEIGHTED_FILTER */
1516
1517/* The following are no longer used and will be removed from libpng-1.7: */
1518#define PNG_FILTER_HEURISTIC_DEFAULT 0 /* Currently "UNWEIGHTED" */
1519#define PNG_FILTER_HEURISTIC_UNWEIGHTED 1 /* Used by libpng < 0.95 */
1520#define PNG_FILTER_HEURISTIC_WEIGHTED 2 /* Experimental feature */
1521#define PNG_FILTER_HEURISTIC_LAST 3 /* Not a valid value */
1522
1523/* Set the library compression level. Currently, valid values range from
1524 * 0 - 9, corresponding directly to the zlib compression levels 0 - 9
1525 * (0 - no compression, 9 - "maximal" compression). Note that tests have
1526 * shown that zlib compression levels 3-6 usually perform as well as level 9
1527 * for PNG images, and do considerably fewer caclulations. In the future,
1528 * these values may not correspond directly to the zlib compression levels.
1529 */
1530#ifdef PNG_WRITE_CUSTOMIZE_COMPRESSION_SUPPORTED
1531PNG_EXPORT(69, void, png_set_compression_level, (png_structrp png_ptr,
1532 int level));
1533
1534PNG_EXPORT(70, void, png_set_compression_mem_level, (png_structrp png_ptr,
1535 int mem_level));
1536
1537PNG_EXPORT(71, void, png_set_compression_strategy, (png_structrp png_ptr,
1538 int strategy));
1539
1540/* If PNG_WRITE_OPTIMIZE_CMF_SUPPORTED is defined, libpng will use a
1541 * smaller value of window_bits if it can do so safely.
1542 */
1543PNG_EXPORT(72, void, png_set_compression_window_bits, (png_structrp png_ptr,
1544 int window_bits));
1545
1546PNG_EXPORT(73, void, png_set_compression_method, (png_structrp png_ptr,
1547 int method));
1548#endif /* WRITE_CUSTOMIZE_COMPRESSION */
1549
1550#ifdef PNG_WRITE_CUSTOMIZE_ZTXT_COMPRESSION_SUPPORTED
1551/* Also set zlib parameters for compressing non-IDAT chunks */
1552PNG_EXPORT(222, void, png_set_text_compression_level, (png_structrp png_ptr,
1553 int level));
1554
1555PNG_EXPORT(223, void, png_set_text_compression_mem_level, (png_structrp png_ptr,
1556 int mem_level));
1557
1558PNG_EXPORT(224, void, png_set_text_compression_strategy, (png_structrp png_ptr,
1559 int strategy));
1560
1561/* If PNG_WRITE_OPTIMIZE_CMF_SUPPORTED is defined, libpng will use a
1562 * smaller value of window_bits if it can do so safely.
1563 */
1564PNG_EXPORT(225, void, png_set_text_compression_window_bits,
1565 (png_structrp png_ptr, int window_bits));
1566
1567PNG_EXPORT(226, void, png_set_text_compression_method, (png_structrp png_ptr,
1568 int method));
1569#endif /* WRITE_CUSTOMIZE_ZTXT_COMPRESSION */
1570#endif /* WRITE */
1571
1572/* These next functions are called for input/output, memory, and error
1573 * handling. They are in the file pngrio.c, pngwio.c, and pngerror.c,
1574 * and call standard C I/O routines such as fread(), fwrite(), and
1575 * fprintf(). These functions can be made to use other I/O routines
1576 * at run time for those applications that need to handle I/O in a
1577 * different manner by calling png_set_???_fn(). See libpng-manual.txt for
1578 * more information.
1579 */
1580
1581#ifdef PNG_STDIO_SUPPORTED
1582/* Initialize the input/output for the PNG file to the default functions. */
1583PNG_EXPORT(74, void, png_init_io, (png_structrp png_ptr, png_FILE_p fp));
1584#endif
1585
1586/* Replace the (error and abort), and warning functions with user
1587 * supplied functions. If no messages are to be printed you must still
1588 * write and use replacement functions. The replacement error_fn should
1589 * still do a longjmp to the last setjmp location if you are using this
1590 * method of error handling. If error_fn or warning_fn is NULL, the
1591 * default function will be used.
1592 */
1593
1594PNG_EXPORT(75, void, png_set_error_fn, (png_structrp png_ptr,
1595 png_voidp error_ptr, png_error_ptr error_fn, png_error_ptr warning_fn));
1596
1597/* Return the user pointer associated with the error functions */
1598PNG_EXPORT(76, png_voidp, png_get_error_ptr, (png_const_structrp png_ptr));
1599
1600/* Replace the default data output functions with a user supplied one(s).
1601 * If buffered output is not used, then output_flush_fn can be set to NULL.
1602 * If PNG_WRITE_FLUSH_SUPPORTED is not defined at libpng compile time
1603 * output_flush_fn will be ignored (and thus can be NULL).
1604 * It is probably a mistake to use NULL for output_flush_fn if
1605 * write_data_fn is not also NULL unless you have built libpng with
1606 * PNG_WRITE_FLUSH_SUPPORTED undefined, because in this case libpng's
1607 * default flush function, which uses the standard *FILE structure, will
1608 * be used.
1609 */
1610PNG_EXPORT(77, void, png_set_write_fn, (png_structrp png_ptr, png_voidp io_ptr,
1611 png_rw_ptr write_data_fn, png_flush_ptr output_flush_fn));
1612
1613/* Replace the default data input function with a user supplied one. */
1614PNG_EXPORT(78, void, png_set_read_fn, (png_structrp png_ptr, png_voidp io_ptr,
1615 png_rw_ptr read_data_fn));
1616
1617/* Return the user pointer associated with the I/O functions */
1618PNG_EXPORT(79, png_voidp, png_get_io_ptr, (png_const_structrp png_ptr));
1619
1620PNG_EXPORT(80, void, png_set_read_status_fn, (png_structrp png_ptr,
1621 png_read_status_ptr read_row_fn));
1622
1623PNG_EXPORT(81, void, png_set_write_status_fn, (png_structrp png_ptr,
1624 png_write_status_ptr write_row_fn));
1625
1626#ifdef PNG_USER_MEM_SUPPORTED
1627/* Replace the default memory allocation functions with user supplied one(s). */
1628PNG_EXPORT(82, void, png_set_mem_fn, (png_structrp png_ptr, png_voidp mem_ptr,
1629 png_malloc_ptr malloc_fn, png_free_ptr free_fn));
1630/* Return the user pointer associated with the memory functions */
1631PNG_EXPORT(83, png_voidp, png_get_mem_ptr, (png_const_structrp png_ptr));
1632#endif
1633
1634#ifdef PNG_READ_USER_TRANSFORM_SUPPORTED
1635PNG_EXPORT(84, void, png_set_read_user_transform_fn, (png_structrp png_ptr,
1636 png_user_transform_ptr read_user_transform_fn));
1637#endif
1638
1639#ifdef PNG_WRITE_USER_TRANSFORM_SUPPORTED
1640PNG_EXPORT(85, void, png_set_write_user_transform_fn, (png_structrp png_ptr,
1641 png_user_transform_ptr write_user_transform_fn));
1642#endif
1643
1644#ifdef PNG_USER_TRANSFORM_PTR_SUPPORTED
1645PNG_EXPORT(86, void, png_set_user_transform_info, (png_structrp png_ptr,
1646 png_voidp user_transform_ptr, int user_transform_depth,
1647 int user_transform_channels));
1648/* Return the user pointer associated with the user transform functions */
1649PNG_EXPORT(87, png_voidp, png_get_user_transform_ptr,
1650 (png_const_structrp png_ptr));
1651#endif
1652
1653#ifdef PNG_USER_TRANSFORM_INFO_SUPPORTED
1654/* Return information about the row currently being processed. Note that these
1655 * APIs do not fail but will return unexpected results if called outside a user
1656 * transform callback. Also note that when transforming an interlaced image the
1657 * row number is the row number within the sub-image of the interlace pass, so
1658 * the value will increase to the height of the sub-image (not the full image)
1659 * then reset to 0 for the next pass.
1660 *
1661 * Use PNG_ROW_FROM_PASS_ROW(row, pass) and PNG_COL_FROM_PASS_COL(col, pass) to
1662 * find the output pixel (x,y) given an interlaced sub-image pixel
1663 * (row,col,pass). (See below for these macros.)
1664 */
1665PNG_EXPORT(217, png_uint_32, png_get_current_row_number, (png_const_structrp));
1666PNG_EXPORT(218, png_byte, png_get_current_pass_number, (png_const_structrp));
1667#endif
1668
1669#ifdef PNG_READ_USER_CHUNKS_SUPPORTED
1670/* This callback is called only for *unknown* chunks. If
1671 * PNG_HANDLE_AS_UNKNOWN_SUPPORTED is set then it is possible to set known
1672 * chunks to be treated as unknown, however in this case the callback must do
1673 * any processing required by the chunk (e.g. by calling the appropriate
1674 * png_set_ APIs.)
1675 *
1676 * There is no write support - on write, by default, all the chunks in the
1677 * 'unknown' list are written in the specified position.
1678 *
1679 * The integer return from the callback function is interpreted thus:
1680 *
1681 * negative: An error occurred; png_chunk_error will be called.
1682 * zero: The chunk was not handled, the chunk will be saved. A critical
1683 * chunk will cause an error at this point unless it is to be saved.
1684 * positive: The chunk was handled, libpng will ignore/discard it.
1685 *
1686 * See "INTERACTION WITH USER CHUNK CALLBACKS" below for important notes about
1687 * how this behavior will change in libpng 1.7
1688 */
1689PNG_EXPORT(88, void, png_set_read_user_chunk_fn, (png_structrp png_ptr,
1690 png_voidp user_chunk_ptr, png_user_chunk_ptr read_user_chunk_fn));
1691#endif
1692
1693#ifdef PNG_USER_CHUNKS_SUPPORTED
1694PNG_EXPORT(89, png_voidp, png_get_user_chunk_ptr, (png_const_structrp png_ptr));
1695#endif
1696
1697#ifdef PNG_PROGRESSIVE_READ_SUPPORTED
1698/* Sets the function callbacks for the push reader, and a pointer to a
1699 * user-defined structure available to the callback functions.
1700 */
1701PNG_EXPORT(90, void, png_set_progressive_read_fn, (png_structrp png_ptr,
1702 png_voidp progressive_ptr, png_progressive_info_ptr info_fn,
1703 png_progressive_row_ptr row_fn, png_progressive_end_ptr end_fn));
1704
1705/* Returns the user pointer associated with the push read functions */
1706PNG_EXPORT(91, png_voidp, png_get_progressive_ptr,
1707 (png_const_structrp png_ptr));
1708
1709/* Function to be called when data becomes available */
1710PNG_EXPORT(92, void, png_process_data, (png_structrp png_ptr,
1711 png_inforp info_ptr, png_bytep buffer, size_t buffer_size));
1712
1713/* A function which may be called *only* within png_process_data to stop the
1714 * processing of any more data. The function returns the number of bytes
1715 * remaining, excluding any that libpng has cached internally. A subsequent
1716 * call to png_process_data must supply these bytes again. If the argument
1717 * 'save' is set to true the routine will first save all the pending data and
1718 * will always return 0.
1719 */
1720PNG_EXPORT(219, size_t, png_process_data_pause, (png_structrp, int save));
1721
1722/* A function which may be called *only* outside (after) a call to
1723 * png_process_data. It returns the number of bytes of data to skip in the
1724 * input. Normally it will return 0, but if it returns a non-zero value the
1725 * application must skip than number of bytes of input data and pass the
1726 * following data to the next call to png_process_data.
1727 */
1728PNG_EXPORT(220, png_uint_32, png_process_data_skip, (png_structrp));
1729
1730/* Function that combines rows. 'new_row' is a flag that should come from
1731 * the callback and be non-NULL if anything needs to be done; the library
1732 * stores its own version of the new data internally and ignores the passed
1733 * in value.
1734 */
1735PNG_EXPORT(93, void, png_progressive_combine_row, (png_const_structrp png_ptr,
1736 png_bytep old_row, png_const_bytep new_row));
1737#endif /* PROGRESSIVE_READ */
1738
1739PNG_EXPORTA(94, png_voidp, png_malloc, (png_const_structrp png_ptr,
1740 png_alloc_size_t size), PNG_ALLOCATED);
1741/* Added at libpng version 1.4.0 */
1742PNG_EXPORTA(95, png_voidp, png_calloc, (png_const_structrp png_ptr,
1743 png_alloc_size_t size), PNG_ALLOCATED);
1744
1745/* Added at libpng version 1.2.4 */
1746PNG_EXPORTA(96, png_voidp, png_malloc_warn, (png_const_structrp png_ptr,
1747 png_alloc_size_t size), PNG_ALLOCATED);
1748
1749/* Frees a pointer allocated by png_malloc() */
1750PNG_EXPORT(97, void, png_free, (png_const_structrp png_ptr, png_voidp ptr));
1751
1752/* Free data that was allocated internally */
1753PNG_EXPORT(98, void, png_free_data, (png_const_structrp png_ptr,
1754 png_inforp info_ptr, png_uint_32 free_me, int num));
1755
1756/* Reassign responsibility for freeing existing data, whether allocated
1757 * by libpng or by the application; this works on the png_info structure passed
1758 * in, it does not change the state for other png_info structures.
1759 *
1760 * It is unlikely that this function works correctly as of 1.6.0 and using it
1761 * may result either in memory leaks or double free of allocated data.
1762 */
1763PNG_EXPORT(99, void, png_data_freer, (png_const_structrp png_ptr,
1764 png_inforp info_ptr, int freer, png_uint_32 mask));
1765
1766/* Assignments for png_data_freer */
1767#define PNG_DESTROY_WILL_FREE_DATA 1
1768#define PNG_SET_WILL_FREE_DATA 1
1769#define PNG_USER_WILL_FREE_DATA 2
1770/* Flags for png_ptr->free_me and info_ptr->free_me */
1771#define PNG_FREE_HIST 0x0008U
1772#define PNG_FREE_ICCP 0x0010U
1773#define PNG_FREE_SPLT 0x0020U
1774#define PNG_FREE_ROWS 0x0040U
1775#define PNG_FREE_PCAL 0x0080U
1776#define PNG_FREE_SCAL 0x0100U
1777#ifdef PNG_STORE_UNKNOWN_CHUNKS_SUPPORTED
1778# define PNG_FREE_UNKN 0x0200U
1779#endif
1780/* PNG_FREE_LIST 0x0400U removed in 1.6.0 because it is ignored */
1781#define PNG_FREE_PLTE 0x1000U
1782#define PNG_FREE_TRNS 0x2000U
1783#define PNG_FREE_TEXT 0x4000U
1784#define PNG_FREE_EXIF 0x8000U /* Added at libpng-1.6.31 */
1785#define PNG_FREE_ALL 0xffffU
1786#define PNG_FREE_MUL 0x4220U /* PNG_FREE_SPLT|PNG_FREE_TEXT|PNG_FREE_UNKN */
1787
1788#ifdef PNG_USER_MEM_SUPPORTED
1789PNG_EXPORTA(100, png_voidp, png_malloc_default, (png_const_structrp png_ptr,
1790 png_alloc_size_t size), PNG_ALLOCATED PNG_DEPRECATED);
1791PNG_EXPORTA(101, void, png_free_default, (png_const_structrp png_ptr,
1792 png_voidp ptr), PNG_DEPRECATED);
1793#endif
1794
1795#ifdef PNG_ERROR_TEXT_SUPPORTED
1796/* Fatal error in PNG image of libpng - can't continue */
1797PNG_EXPORTA(102, void, png_error, (png_const_structrp png_ptr,
1798 png_const_charp error_message), PNG_NORETURN);
1799
1800/* The same, but the chunk name is prepended to the error string. */
1801PNG_EXPORTA(103, void, png_chunk_error, (png_const_structrp png_ptr,
1802 png_const_charp error_message), PNG_NORETURN);
1803
1804#else
1805/* Fatal error in PNG image of libpng - can't continue */
1806PNG_EXPORTA(104, void, png_err, (png_const_structrp png_ptr), PNG_NORETURN);
1807# define png_error(s1,s2) png_err(s1)
1808# define png_chunk_error(s1,s2) png_err(s1)
1809#endif
1810
1811#ifdef PNG_WARNINGS_SUPPORTED
1812/* Non-fatal error in libpng. Can continue, but may have a problem. */
1813PNG_EXPORT(105, void, png_warning, (png_const_structrp png_ptr,
1814 png_const_charp warning_message));
1815
1816/* Non-fatal error in libpng, chunk name is prepended to message. */
1817PNG_EXPORT(106, void, png_chunk_warning, (png_const_structrp png_ptr,
1818 png_const_charp warning_message));
1819#else
1820# define png_warning(s1,s2) ((void)(s1))
1821# define png_chunk_warning(s1,s2) ((void)(s1))
1822#endif
1823
1824#ifdef PNG_BENIGN_ERRORS_SUPPORTED
1825/* Benign error in libpng. Can continue, but may have a problem.
1826 * User can choose whether to handle as a fatal error or as a warning. */
1827PNG_EXPORT(107, void, png_benign_error, (png_const_structrp png_ptr,
1828 png_const_charp warning_message));
1829
1830#ifdef PNG_READ_SUPPORTED
1831/* Same, chunk name is prepended to message (only during read) */
1832PNG_EXPORT(108, void, png_chunk_benign_error, (png_const_structrp png_ptr,
1833 png_const_charp warning_message));
1834#endif
1835
1836PNG_EXPORT(109, void, png_set_benign_errors,
1837 (png_structrp png_ptr, int allowed));
1838#else
1839# ifdef PNG_ALLOW_BENIGN_ERRORS
1840# define png_benign_error png_warning
1841# define png_chunk_benign_error png_chunk_warning
1842# else
1843# define png_benign_error png_error
1844# define png_chunk_benign_error png_chunk_error
1845# endif
1846#endif
1847
1848/* The png_set_<chunk> functions are for storing values in the png_info_struct.
1849 * Similarly, the png_get_<chunk> calls are used to read values from the
1850 * png_info_struct, either storing the parameters in the passed variables, or
1851 * setting pointers into the png_info_struct where the data is stored. The
1852 * png_get_<chunk> functions return a non-zero value if the data was available
1853 * in info_ptr, or return zero and do not change any of the parameters if the
1854 * data was not available.
1855 *
1856 * These functions should be used instead of directly accessing png_info
1857 * to avoid problems with future changes in the size and internal layout of
1858 * png_info_struct.
1859 */
1860/* Returns "flag" if chunk data is valid in info_ptr. */
1861PNG_EXPORT(110, png_uint_32, png_get_valid, (png_const_structrp png_ptr,
1862 png_const_inforp info_ptr, png_uint_32 flag));
1863
1864/* Returns number of bytes needed to hold a transformed row. */
1865PNG_EXPORT(111, size_t, png_get_rowbytes, (png_const_structrp png_ptr,
1866 png_const_inforp info_ptr));
1867
1868#ifdef PNG_INFO_IMAGE_SUPPORTED
1869/* Returns row_pointers, which is an array of pointers to scanlines that was
1870 * returned from png_read_png().
1871 */
1872PNG_EXPORT(112, png_bytepp, png_get_rows, (png_const_structrp png_ptr,
1873 png_const_inforp info_ptr));
1874
1875/* Set row_pointers, which is an array of pointers to scanlines for use
1876 * by png_write_png().
1877 */
1878PNG_EXPORT(113, void, png_set_rows, (png_const_structrp png_ptr,
1879 png_inforp info_ptr, png_bytepp row_pointers));
1880#endif
1881
1882/* Returns number of color channels in image. */
1883PNG_EXPORT(114, png_byte, png_get_channels, (png_const_structrp png_ptr,
1884 png_const_inforp info_ptr));
1885
1886#ifdef PNG_EASY_ACCESS_SUPPORTED
1887/* Returns image width in pixels. */
1888PNG_EXPORT(115, png_uint_32, png_get_image_width, (png_const_structrp png_ptr,
1889 png_const_inforp info_ptr));
1890
1891/* Returns image height in pixels. */
1892PNG_EXPORT(116, png_uint_32, png_get_image_height, (png_const_structrp png_ptr,
1893 png_const_inforp info_ptr));
1894
1895/* Returns image bit_depth. */
1896PNG_EXPORT(117, png_byte, png_get_bit_depth, (png_const_structrp png_ptr,
1897 png_const_inforp info_ptr));
1898
1899/* Returns image color_type. */
1900PNG_EXPORT(118, png_byte, png_get_color_type, (png_const_structrp png_ptr,
1901 png_const_inforp info_ptr));
1902
1903/* Returns image filter_type. */
1904PNG_EXPORT(119, png_byte, png_get_filter_type, (png_const_structrp png_ptr,
1905 png_const_inforp info_ptr));
1906
1907/* Returns image interlace_type. */
1908PNG_EXPORT(120, png_byte, png_get_interlace_type, (png_const_structrp png_ptr,
1909 png_const_inforp info_ptr));
1910
1911/* Returns image compression_type. */
1912PNG_EXPORT(121, png_byte, png_get_compression_type, (png_const_structrp png_ptr,
1913 png_const_inforp info_ptr));
1914
1915/* Returns image resolution in pixels per meter, from pHYs chunk data. */
1916PNG_EXPORT(122, png_uint_32, png_get_pixels_per_meter,
1917 (png_const_structrp png_ptr, png_const_inforp info_ptr));
1918PNG_EXPORT(123, png_uint_32, png_get_x_pixels_per_meter,
1919 (png_const_structrp png_ptr, png_const_inforp info_ptr));
1920PNG_EXPORT(124, png_uint_32, png_get_y_pixels_per_meter,
1921 (png_const_structrp png_ptr, png_const_inforp info_ptr));
1922
1923/* Returns pixel aspect ratio, computed from pHYs chunk data. */
1924PNG_FP_EXPORT(125, float, png_get_pixel_aspect_ratio,
1925 (png_const_structrp png_ptr, png_const_inforp info_ptr))
1926PNG_FIXED_EXPORT(210, png_fixed_point, png_get_pixel_aspect_ratio_fixed,
1927 (png_const_structrp png_ptr, png_const_inforp info_ptr))
1928
1929/* Returns image x, y offset in pixels or microns, from oFFs chunk data. */
1930PNG_EXPORT(126, png_int_32, png_get_x_offset_pixels,
1931 (png_const_structrp png_ptr, png_const_inforp info_ptr));
1932PNG_EXPORT(127, png_int_32, png_get_y_offset_pixels,
1933 (png_const_structrp png_ptr, png_const_inforp info_ptr));
1934PNG_EXPORT(128, png_int_32, png_get_x_offset_microns,
1935 (png_const_structrp png_ptr, png_const_inforp info_ptr));
1936PNG_EXPORT(129, png_int_32, png_get_y_offset_microns,
1937 (png_const_structrp png_ptr, png_const_inforp info_ptr));
1938
1939#endif /* EASY_ACCESS */
1940
1941#ifdef PNG_READ_SUPPORTED
1942/* Returns pointer to signature string read from PNG header */
1943PNG_EXPORT(130, png_const_bytep, png_get_signature, (png_const_structrp png_ptr,
1944 png_const_inforp info_ptr));
1945#endif
1946
1947#ifdef PNG_bKGD_SUPPORTED
1948PNG_EXPORT(131, png_uint_32, png_get_bKGD, (png_const_structrp png_ptr,
1949 png_inforp info_ptr, png_color_16p *background));
1950#endif
1951
1952#ifdef PNG_bKGD_SUPPORTED
1953PNG_EXPORT(132, void, png_set_bKGD, (png_const_structrp png_ptr,
1954 png_inforp info_ptr, png_const_color_16p background));
1955#endif
1956
1957#ifdef PNG_cHRM_SUPPORTED
1958PNG_FP_EXPORT(133, png_uint_32, png_get_cHRM, (png_const_structrp png_ptr,
1959 png_const_inforp info_ptr, double *white_x, double *white_y, double *red_x,
1960 double *red_y, double *green_x, double *green_y, double *blue_x,
1961 double *blue_y))
1962PNG_FP_EXPORT(230, png_uint_32, png_get_cHRM_XYZ, (png_const_structrp png_ptr,
1963 png_const_inforp info_ptr, double *red_X, double *red_Y, double *red_Z,
1964 double *green_X, double *green_Y, double *green_Z, double *blue_X,
1965 double *blue_Y, double *blue_Z))
1966PNG_FIXED_EXPORT(134, png_uint_32, png_get_cHRM_fixed,
1967 (png_const_structrp png_ptr, png_const_inforp info_ptr,
1968 png_fixed_point *int_white_x, png_fixed_point *int_white_y,
1969 png_fixed_point *int_red_x, png_fixed_point *int_red_y,
1970 png_fixed_point *int_green_x, png_fixed_point *int_green_y,
1971 png_fixed_point *int_blue_x, png_fixed_point *int_blue_y))
1972PNG_FIXED_EXPORT(231, png_uint_32, png_get_cHRM_XYZ_fixed,
1973 (png_const_structrp png_ptr, png_const_inforp info_ptr,
1974 png_fixed_point *int_red_X, png_fixed_point *int_red_Y,
1975 png_fixed_point *int_red_Z, png_fixed_point *int_green_X,
1976 png_fixed_point *int_green_Y, png_fixed_point *int_green_Z,
1977 png_fixed_point *int_blue_X, png_fixed_point *int_blue_Y,
1978 png_fixed_point *int_blue_Z))
1979#endif
1980
1981#ifdef PNG_cHRM_SUPPORTED
1982PNG_FP_EXPORT(135, void, png_set_cHRM, (png_const_structrp png_ptr,
1983 png_inforp info_ptr,
1984 double white_x, double white_y, double red_x, double red_y, double green_x,
1985 double green_y, double blue_x, double blue_y))
1986PNG_FP_EXPORT(232, void, png_set_cHRM_XYZ, (png_const_structrp png_ptr,
1987 png_inforp info_ptr, double red_X, double red_Y, double red_Z,
1988 double green_X, double green_Y, double green_Z, double blue_X,
1989 double blue_Y, double blue_Z))
1990PNG_FIXED_EXPORT(136, void, png_set_cHRM_fixed, (png_const_structrp png_ptr,
1991 png_inforp info_ptr, png_fixed_point int_white_x,
1992 png_fixed_point int_white_y, png_fixed_point int_red_x,
1993 png_fixed_point int_red_y, png_fixed_point int_green_x,
1994 png_fixed_point int_green_y, png_fixed_point int_blue_x,
1995 png_fixed_point int_blue_y))
1996PNG_FIXED_EXPORT(233, void, png_set_cHRM_XYZ_fixed, (png_const_structrp png_ptr,
1997 png_inforp info_ptr, png_fixed_point int_red_X, png_fixed_point int_red_Y,
1998 png_fixed_point int_red_Z, png_fixed_point int_green_X,
1999 png_fixed_point int_green_Y, png_fixed_point int_green_Z,
2000 png_fixed_point int_blue_X, png_fixed_point int_blue_Y,
2001 png_fixed_point int_blue_Z))
2002#endif
2003
2004#ifdef PNG_eXIf_SUPPORTED
2005PNG_EXPORT(246, png_uint_32, png_get_eXIf, (png_const_structrp png_ptr,
2006 png_inforp info_ptr, png_bytep *exif));
2007PNG_EXPORT(247, void, png_set_eXIf, (png_const_structrp png_ptr,
2008 png_inforp info_ptr, png_bytep exif));
2009
2010PNG_EXPORT(248, png_uint_32, png_get_eXIf_1, (png_const_structrp png_ptr,
2011 png_const_inforp info_ptr, png_uint_32 *num_exif, png_bytep *exif));
2012PNG_EXPORT(249, void, png_set_eXIf_1, (png_const_structrp png_ptr,
2013 png_inforp info_ptr, png_uint_32 num_exif, png_bytep exif));
2014#endif
2015
2016#ifdef PNG_gAMA_SUPPORTED
2017PNG_FP_EXPORT(137, png_uint_32, png_get_gAMA, (png_const_structrp png_ptr,
2018 png_const_inforp info_ptr, double *file_gamma))
2019PNG_FIXED_EXPORT(138, png_uint_32, png_get_gAMA_fixed,
2020 (png_const_structrp png_ptr, png_const_inforp info_ptr,
2021 png_fixed_point *int_file_gamma))
2022#endif
2023
2024#ifdef PNG_gAMA_SUPPORTED
2025PNG_FP_EXPORT(139, void, png_set_gAMA, (png_const_structrp png_ptr,
2026 png_inforp info_ptr, double file_gamma))
2027PNG_FIXED_EXPORT(140, void, png_set_gAMA_fixed, (png_const_structrp png_ptr,
2028 png_inforp info_ptr, png_fixed_point int_file_gamma))
2029#endif
2030
2031#ifdef PNG_hIST_SUPPORTED
2032PNG_EXPORT(141, png_uint_32, png_get_hIST, (png_const_structrp png_ptr,
2033 png_inforp info_ptr, png_uint_16p *hist));
2034PNG_EXPORT(142, void, png_set_hIST, (png_const_structrp png_ptr,
2035 png_inforp info_ptr, png_const_uint_16p hist));
2036#endif
2037
2038PNG_EXPORT(143, png_uint_32, png_get_IHDR, (png_const_structrp png_ptr,
2039 png_const_inforp info_ptr, png_uint_32 *width, png_uint_32 *height,
2040 int *bit_depth, int *color_type, int *interlace_method,
2041 int *compression_method, int *filter_method));
2042
2043PNG_EXPORT(144, void, png_set_IHDR, (png_const_structrp png_ptr,
2044 png_inforp info_ptr, png_uint_32 width, png_uint_32 height, int bit_depth,
2045 int color_type, int interlace_method, int compression_method,
2046 int filter_method));
2047
2048#ifdef PNG_oFFs_SUPPORTED
2049PNG_EXPORT(145, png_uint_32, png_get_oFFs, (png_const_structrp png_ptr,
2050 png_const_inforp info_ptr, png_int_32 *offset_x, png_int_32 *offset_y,
2051 int *unit_type));
2052#endif
2053
2054#ifdef PNG_oFFs_SUPPORTED
2055PNG_EXPORT(146, void, png_set_oFFs, (png_const_structrp png_ptr,
2056 png_inforp info_ptr, png_int_32 offset_x, png_int_32 offset_y,
2057 int unit_type));
2058#endif
2059
2060#ifdef PNG_pCAL_SUPPORTED
2061PNG_EXPORT(147, png_uint_32, png_get_pCAL, (png_const_structrp png_ptr,
2062 png_inforp info_ptr, png_charp *purpose, png_int_32 *X0,
2063 png_int_32 *X1, int *type, int *nparams, png_charp *units,
2064 png_charpp *params));
2065#endif
2066
2067#ifdef PNG_pCAL_SUPPORTED
2068PNG_EXPORT(148, void, png_set_pCAL, (png_const_structrp png_ptr,
2069 png_inforp info_ptr, png_const_charp purpose, png_int_32 X0, png_int_32 X1,
2070 int type, int nparams, png_const_charp units, png_charpp params));
2071#endif
2072
2073#ifdef PNG_pHYs_SUPPORTED
2074PNG_EXPORT(149, png_uint_32, png_get_pHYs, (png_const_structrp png_ptr,
2075 png_const_inforp info_ptr, png_uint_32 *res_x, png_uint_32 *res_y,
2076 int *unit_type));
2077#endif
2078
2079#ifdef PNG_pHYs_SUPPORTED
2080PNG_EXPORT(150, void, png_set_pHYs, (png_const_structrp png_ptr,
2081 png_inforp info_ptr, png_uint_32 res_x, png_uint_32 res_y, int unit_type));
2082#endif
2083
2084PNG_EXPORT(151, png_uint_32, png_get_PLTE, (png_const_structrp png_ptr,
2085 png_inforp info_ptr, png_colorp *palette, int *num_palette));
2086
2087PNG_EXPORT(152, void, png_set_PLTE, (png_structrp png_ptr,
2088 png_inforp info_ptr, png_const_colorp palette, int num_palette));
2089
2090#ifdef PNG_sBIT_SUPPORTED
2091PNG_EXPORT(153, png_uint_32, png_get_sBIT, (png_const_structrp png_ptr,
2092 png_inforp info_ptr, png_color_8p *sig_bit));
2093#endif
2094
2095#ifdef PNG_sBIT_SUPPORTED
2096PNG_EXPORT(154, void, png_set_sBIT, (png_const_structrp png_ptr,
2097 png_inforp info_ptr, png_const_color_8p sig_bit));
2098#endif
2099
2100#ifdef PNG_sRGB_SUPPORTED
2101PNG_EXPORT(155, png_uint_32, png_get_sRGB, (png_const_structrp png_ptr,
2102 png_const_inforp info_ptr, int *file_srgb_intent));
2103#endif
2104
2105#ifdef PNG_sRGB_SUPPORTED
2106PNG_EXPORT(156, void, png_set_sRGB, (png_const_structrp png_ptr,
2107 png_inforp info_ptr, int srgb_intent));
2108PNG_EXPORT(157, void, png_set_sRGB_gAMA_and_cHRM, (png_const_structrp png_ptr,
2109 png_inforp info_ptr, int srgb_intent));
2110#endif
2111
2112#ifdef PNG_iCCP_SUPPORTED
2113PNG_EXPORT(158, png_uint_32, png_get_iCCP, (png_const_structrp png_ptr,
2114 png_inforp info_ptr, png_charpp name, int *compression_type,
2115 png_bytepp profile, png_uint_32 *proflen));
2116#endif
2117
2118#ifdef PNG_iCCP_SUPPORTED
2119PNG_EXPORT(159, void, png_set_iCCP, (png_const_structrp png_ptr,
2120 png_inforp info_ptr, png_const_charp name, int compression_type,
2121 png_const_bytep profile, png_uint_32 proflen));
2122#endif
2123
2124#ifdef PNG_sPLT_SUPPORTED
2125PNG_EXPORT(160, int, png_get_sPLT, (png_const_structrp png_ptr,
2126 png_inforp info_ptr, png_sPLT_tpp entries));
2127#endif
2128
2129#ifdef PNG_sPLT_SUPPORTED
2130PNG_EXPORT(161, void, png_set_sPLT, (png_const_structrp png_ptr,
2131 png_inforp info_ptr, png_const_sPLT_tp entries, int nentries));
2132#endif
2133
2134#ifdef PNG_TEXT_SUPPORTED
2135/* png_get_text also returns the number of text chunks in *num_text */
2136PNG_EXPORT(162, int, png_get_text, (png_const_structrp png_ptr,
2137 png_inforp info_ptr, png_textp *text_ptr, int *num_text));
2138#endif
2139
2140/* Note while png_set_text() will accept a structure whose text,
2141 * language, and translated keywords are NULL pointers, the structure
2142 * returned by png_get_text will always contain regular
2143 * zero-terminated C strings. They might be empty strings but
2144 * they will never be NULL pointers.
2145 */
2146
2147#ifdef PNG_TEXT_SUPPORTED
2148PNG_EXPORT(163, void, png_set_text, (png_const_structrp png_ptr,
2149 png_inforp info_ptr, png_const_textp text_ptr, int num_text));
2150#endif
2151
2152#ifdef PNG_tIME_SUPPORTED
2153PNG_EXPORT(164, png_uint_32, png_get_tIME, (png_const_structrp png_ptr,
2154 png_inforp info_ptr, png_timep *mod_time));
2155#endif
2156
2157#ifdef PNG_tIME_SUPPORTED
2158PNG_EXPORT(165, void, png_set_tIME, (png_const_structrp png_ptr,
2159 png_inforp info_ptr, png_const_timep mod_time));
2160#endif
2161
2162#ifdef PNG_tRNS_SUPPORTED
2163PNG_EXPORT(166, png_uint_32, png_get_tRNS, (png_const_structrp png_ptr,
2164 png_inforp info_ptr, png_bytep *trans_alpha, int *num_trans,
2165 png_color_16p *trans_color));
2166#endif
2167
2168#ifdef PNG_tRNS_SUPPORTED
2169PNG_EXPORT(167, void, png_set_tRNS, (png_structrp png_ptr,
2170 png_inforp info_ptr, png_const_bytep trans_alpha, int num_trans,
2171 png_const_color_16p trans_color));
2172#endif
2173
2174#ifdef PNG_sCAL_SUPPORTED
2175PNG_FP_EXPORT(168, png_uint_32, png_get_sCAL, (png_const_structrp png_ptr,
2176 png_const_inforp info_ptr, int *unit, double *width, double *height))
2177#if defined(PNG_FLOATING_ARITHMETIC_SUPPORTED) || \
2178 defined(PNG_FLOATING_POINT_SUPPORTED)
2179/* NOTE: this API is currently implemented using floating point arithmetic,
2180 * consequently it can only be used on systems with floating point support.
2181 * In any case the range of values supported by png_fixed_point is small and it
2182 * is highly recommended that png_get_sCAL_s be used instead.
2183 */
2184PNG_FIXED_EXPORT(214, png_uint_32, png_get_sCAL_fixed,
2185 (png_const_structrp png_ptr, png_const_inforp info_ptr, int *unit,
2186 png_fixed_point *width, png_fixed_point *height))
2187#endif
2188PNG_EXPORT(169, png_uint_32, png_get_sCAL_s,
2189 (png_const_structrp png_ptr, png_const_inforp info_ptr, int *unit,
2190 png_charpp swidth, png_charpp sheight));
2191
2192PNG_FP_EXPORT(170, void, png_set_sCAL, (png_const_structrp png_ptr,
2193 png_inforp info_ptr, int unit, double width, double height))
2194PNG_FIXED_EXPORT(213, void, png_set_sCAL_fixed, (png_const_structrp png_ptr,
2195 png_inforp info_ptr, int unit, png_fixed_point width,
2196 png_fixed_point height))
2197PNG_EXPORT(171, void, png_set_sCAL_s, (png_const_structrp png_ptr,
2198 png_inforp info_ptr, int unit,
2199 png_const_charp swidth, png_const_charp sheight));
2200#endif /* sCAL */
2201
2202#ifdef PNG_SET_UNKNOWN_CHUNKS_SUPPORTED
2203/* Provide the default handling for all unknown chunks or, optionally, for
2204 * specific unknown chunks.
2205 *
2206 * NOTE: prior to 1.6.0 the handling specified for particular chunks on read was
2207 * ignored and the default was used, the per-chunk setting only had an effect on
2208 * write. If you wish to have chunk-specific handling on read in code that must
2209 * work on earlier versions you must use a user chunk callback to specify the
2210 * desired handling (keep or discard.)
2211 *
2212 * The 'keep' parameter is a PNG_HANDLE_CHUNK_ value as listed below. The
2213 * parameter is interpreted as follows:
2214 *
2215 * READ:
2216 * PNG_HANDLE_CHUNK_AS_DEFAULT:
2217 * Known chunks: do normal libpng processing, do not keep the chunk (but
2218 * see the comments below about PNG_HANDLE_AS_UNKNOWN_SUPPORTED)
2219 * Unknown chunks: for a specific chunk use the global default, when used
2220 * as the default discard the chunk data.
2221 * PNG_HANDLE_CHUNK_NEVER:
2222 * Discard the chunk data.
2223 * PNG_HANDLE_CHUNK_IF_SAFE:
2224 * Keep the chunk data if the chunk is not critical else raise a chunk
2225 * error.
2226 * PNG_HANDLE_CHUNK_ALWAYS:
2227 * Keep the chunk data.
2228 *
2229 * If the chunk data is saved it can be retrieved using png_get_unknown_chunks,
2230 * below. Notice that specifying "AS_DEFAULT" as a global default is equivalent
2231 * to specifying "NEVER", however when "AS_DEFAULT" is used for specific chunks
2232 * it simply resets the behavior to the libpng default.
2233 *
2234 * INTERACTION WITH USER CHUNK CALLBACKS:
2235 * The per-chunk handling is always used when there is a png_user_chunk_ptr
2236 * callback and the callback returns 0; the chunk is then always stored *unless*
2237 * it is critical and the per-chunk setting is other than ALWAYS. Notice that
2238 * the global default is *not* used in this case. (In effect the per-chunk
2239 * value is incremented to at least IF_SAFE.)
2240 *
2241 * IMPORTANT NOTE: this behavior will change in libpng 1.7 - the global and
2242 * per-chunk defaults will be honored. If you want to preserve the current
2243 * behavior when your callback returns 0 you must set PNG_HANDLE_CHUNK_IF_SAFE
2244 * as the default - if you don't do this libpng 1.6 will issue a warning.
2245 *
2246 * If you want unhandled unknown chunks to be discarded in libpng 1.6 and
2247 * earlier simply return '1' (handled).
2248 *
2249 * PNG_HANDLE_AS_UNKNOWN_SUPPORTED:
2250 * If this is *not* set known chunks will always be handled by libpng and
2251 * will never be stored in the unknown chunk list. Known chunks listed to
2252 * png_set_keep_unknown_chunks will have no effect. If it is set then known
2253 * chunks listed with a keep other than AS_DEFAULT will *never* be processed
2254 * by libpng, in addition critical chunks must either be processed by the
2255 * callback or saved.
2256 *
2257 * The IHDR and IEND chunks must not be listed. Because this turns off the
2258 * default handling for chunks that would otherwise be recognized the
2259 * behavior of libpng transformations may well become incorrect!
2260 *
2261 * WRITE:
2262 * When writing chunks the options only apply to the chunks specified by
2263 * png_set_unknown_chunks (below), libpng will *always* write known chunks
2264 * required by png_set_ calls and will always write the core critical chunks
2265 * (as required for PLTE).
2266 *
2267 * Each chunk in the png_set_unknown_chunks list is looked up in the
2268 * png_set_keep_unknown_chunks list to find the keep setting, this is then
2269 * interpreted as follows:
2270 *
2271 * PNG_HANDLE_CHUNK_AS_DEFAULT:
2272 * Write safe-to-copy chunks and write other chunks if the global
2273 * default is set to _ALWAYS, otherwise don't write this chunk.
2274 * PNG_HANDLE_CHUNK_NEVER:
2275 * Do not write the chunk.
2276 * PNG_HANDLE_CHUNK_IF_SAFE:
2277 * Write the chunk if it is safe-to-copy, otherwise do not write it.
2278 * PNG_HANDLE_CHUNK_ALWAYS:
2279 * Write the chunk.
2280 *
2281 * Note that the default behavior is effectively the opposite of the read case -
2282 * in read unknown chunks are not stored by default, in write they are written
2283 * by default. Also the behavior of PNG_HANDLE_CHUNK_IF_SAFE is very different
2284 * - on write the safe-to-copy bit is checked, on read the critical bit is
2285 * checked and on read if the chunk is critical an error will be raised.
2286 *
2287 * num_chunks:
2288 * ===========
2289 * If num_chunks is positive, then the "keep" parameter specifies the manner
2290 * for handling only those chunks appearing in the chunk_list array,
2291 * otherwise the chunk list array is ignored.
2292 *
2293 * If num_chunks is 0 the "keep" parameter specifies the default behavior for
2294 * unknown chunks, as described above.
2295 *
2296 * If num_chunks is negative, then the "keep" parameter specifies the manner
2297 * for handling all unknown chunks plus all chunks recognized by libpng
2298 * except for the IHDR, PLTE, tRNS, IDAT, and IEND chunks (which continue to
2299 * be processed by libpng.
2300 */
2301#ifdef PNG_HANDLE_AS_UNKNOWN_SUPPORTED
2302PNG_EXPORT(172, void, png_set_keep_unknown_chunks, (png_structrp png_ptr,
2303 int keep, png_const_bytep chunk_list, int num_chunks));
2304#endif /* HANDLE_AS_UNKNOWN */
2305
2306/* The "keep" PNG_HANDLE_CHUNK_ parameter for the specified chunk is returned;
2307 * the result is therefore true (non-zero) if special handling is required,
2308 * false for the default handling.
2309 */
2310PNG_EXPORT(173, int, png_handle_as_unknown, (png_const_structrp png_ptr,
2311 png_const_bytep chunk_name));
2312#endif /* SET_UNKNOWN_CHUNKS */
2313
2314#ifdef PNG_STORE_UNKNOWN_CHUNKS_SUPPORTED
2315PNG_EXPORT(174, void, png_set_unknown_chunks, (png_const_structrp png_ptr,
2316 png_inforp info_ptr, png_const_unknown_chunkp unknowns,
2317 int num_unknowns));
2318 /* NOTE: prior to 1.6.0 this routine set the 'location' field of the added
2319 * unknowns to the location currently stored in the png_struct. This is
2320 * invariably the wrong value on write. To fix this call the following API
2321 * for each chunk in the list with the correct location. If you know your
2322 * code won't be compiled on earlier versions you can rely on
2323 * png_set_unknown_chunks(write-ptr, png_get_unknown_chunks(read-ptr)) doing
2324 * the correct thing.
2325 */
2326
2327PNG_EXPORT(175, void, png_set_unknown_chunk_location,
2328 (png_const_structrp png_ptr, png_inforp info_ptr, int chunk, int location));
2329
2330PNG_EXPORT(176, int, png_get_unknown_chunks, (png_const_structrp png_ptr,
2331 png_inforp info_ptr, png_unknown_chunkpp entries));
2332#endif
2333
2334/* Png_free_data() will turn off the "valid" flag for anything it frees.
2335 * If you need to turn it off for a chunk that your application has freed,
2336 * you can use png_set_invalid(png_ptr, info_ptr, PNG_INFO_CHNK);
2337 */
2338PNG_EXPORT(177, void, png_set_invalid, (png_const_structrp png_ptr,
2339 png_inforp info_ptr, int mask));
2340
2341#ifdef PNG_INFO_IMAGE_SUPPORTED
2342/* The "params" pointer is currently not used and is for future expansion. */
2343#ifdef PNG_SEQUENTIAL_READ_SUPPORTED
2344PNG_EXPORT(178, void, png_read_png, (png_structrp png_ptr, png_inforp info_ptr,
2345 int transforms, png_voidp params));
2346#endif
2347#ifdef PNG_WRITE_SUPPORTED
2348PNG_EXPORT(179, void, png_write_png, (png_structrp png_ptr, png_inforp info_ptr,
2349 int transforms, png_voidp params));
2350#endif
2351#endif
2352
2353PNG_EXPORT(180, png_const_charp, png_get_copyright,
2354 (png_const_structrp png_ptr));
2355PNG_EXPORT(181, png_const_charp, png_get_header_ver,
2356 (png_const_structrp png_ptr));
2357PNG_EXPORT(182, png_const_charp, png_get_header_version,
2358 (png_const_structrp png_ptr));
2359PNG_EXPORT(183, png_const_charp, png_get_libpng_ver,
2360 (png_const_structrp png_ptr));
2361
2362#ifdef PNG_MNG_FEATURES_SUPPORTED
2363PNG_EXPORT(184, png_uint_32, png_permit_mng_features, (png_structrp png_ptr,
2364 png_uint_32 mng_features_permitted));
2365#endif
2366
2367/* For use in png_set_keep_unknown, added to version 1.2.6 */
2368#define PNG_HANDLE_CHUNK_AS_DEFAULT 0
2369#define PNG_HANDLE_CHUNK_NEVER 1
2370#define PNG_HANDLE_CHUNK_IF_SAFE 2
2371#define PNG_HANDLE_CHUNK_ALWAYS 3
2372#define PNG_HANDLE_CHUNK_LAST 4
2373
2374/* Strip the prepended error numbers ("#nnn ") from error and warning
2375 * messages before passing them to the error or warning handler.
2376 */
2377#ifdef PNG_ERROR_NUMBERS_SUPPORTED
2378PNG_EXPORT(185, void, png_set_strip_error_numbers, (png_structrp png_ptr,
2379 png_uint_32 strip_mode));
2380#endif
2381
2382/* Added in libpng-1.2.6 */
2383#ifdef PNG_SET_USER_LIMITS_SUPPORTED
2384PNG_EXPORT(186, void, png_set_user_limits, (png_structrp png_ptr,
2385 png_uint_32 user_width_max, png_uint_32 user_height_max));
2386PNG_EXPORT(187, png_uint_32, png_get_user_width_max,
2387 (png_const_structrp png_ptr));
2388PNG_EXPORT(188, png_uint_32, png_get_user_height_max,
2389 (png_const_structrp png_ptr));
2390/* Added in libpng-1.4.0 */
2391PNG_EXPORT(189, void, png_set_chunk_cache_max, (png_structrp png_ptr,
2392 png_uint_32 user_chunk_cache_max));
2393PNG_EXPORT(190, png_uint_32, png_get_chunk_cache_max,
2394 (png_const_structrp png_ptr));
2395/* Added in libpng-1.4.1 */
2396PNG_EXPORT(191, void, png_set_chunk_malloc_max, (png_structrp png_ptr,
2397 png_alloc_size_t user_chunk_cache_max));
2398PNG_EXPORT(192, png_alloc_size_t, png_get_chunk_malloc_max,
2399 (png_const_structrp png_ptr));
2400#endif
2401
2402#if defined(PNG_INCH_CONVERSIONS_SUPPORTED)
2403PNG_EXPORT(193, png_uint_32, png_get_pixels_per_inch,
2404 (png_const_structrp png_ptr, png_const_inforp info_ptr));
2405
2406PNG_EXPORT(194, png_uint_32, png_get_x_pixels_per_inch,
2407 (png_const_structrp png_ptr, png_const_inforp info_ptr));
2408
2409PNG_EXPORT(195, png_uint_32, png_get_y_pixels_per_inch,
2410 (png_const_structrp png_ptr, png_const_inforp info_ptr));
2411
2412PNG_FP_EXPORT(196, float, png_get_x_offset_inches,
2413 (png_const_structrp png_ptr, png_const_inforp info_ptr))
2414#ifdef PNG_FIXED_POINT_SUPPORTED /* otherwise not implemented. */
2415PNG_FIXED_EXPORT(211, png_fixed_point, png_get_x_offset_inches_fixed,
2416 (png_const_structrp png_ptr, png_const_inforp info_ptr))
2417#endif
2418
2419PNG_FP_EXPORT(197, float, png_get_y_offset_inches, (png_const_structrp png_ptr,
2420 png_const_inforp info_ptr))
2421#ifdef PNG_FIXED_POINT_SUPPORTED /* otherwise not implemented. */
2422PNG_FIXED_EXPORT(212, png_fixed_point, png_get_y_offset_inches_fixed,
2423 (png_const_structrp png_ptr, png_const_inforp info_ptr))
2424#endif
2425
2426# ifdef PNG_pHYs_SUPPORTED
2427PNG_EXPORT(198, png_uint_32, png_get_pHYs_dpi, (png_const_structrp png_ptr,
2428 png_const_inforp info_ptr, png_uint_32 *res_x, png_uint_32 *res_y,
2429 int *unit_type));
2430# endif /* pHYs */
2431#endif /* INCH_CONVERSIONS */
2432
2433/* Added in libpng-1.4.0 */
2434#ifdef PNG_IO_STATE_SUPPORTED
2435PNG_EXPORT(199, png_uint_32, png_get_io_state, (png_const_structrp png_ptr));
2436
2437/* Removed from libpng 1.6; use png_get_io_chunk_type. */
2438PNG_REMOVED(200, png_const_bytep, png_get_io_chunk_name, (png_structrp png_ptr),
2439 PNG_DEPRECATED)
2440
2441PNG_EXPORT(216, png_uint_32, png_get_io_chunk_type,
2442 (png_const_structrp png_ptr));
2443
2444/* The flags returned by png_get_io_state() are the following: */
2445# define PNG_IO_NONE 0x0000 /* no I/O at this moment */
2446# define PNG_IO_READING 0x0001 /* currently reading */
2447# define PNG_IO_WRITING 0x0002 /* currently writing */
2448# define PNG_IO_SIGNATURE 0x0010 /* currently at the file signature */
2449# define PNG_IO_CHUNK_HDR 0x0020 /* currently at the chunk header */
2450# define PNG_IO_CHUNK_DATA 0x0040 /* currently at the chunk data */
2451# define PNG_IO_CHUNK_CRC 0x0080 /* currently at the chunk crc */
2452# define PNG_IO_MASK_OP 0x000f /* current operation: reading/writing */
2453# define PNG_IO_MASK_LOC 0x00f0 /* current location: sig/hdr/data/crc */
2454#endif /* IO_STATE */
2455
2456/* Interlace support. The following macros are always defined so that if
2457 * libpng interlace handling is turned off the macros may be used to handle
2458 * interlaced images within the application.
2459 */
2460#define PNG_INTERLACE_ADAM7_PASSES 7
2461
2462/* Two macros to return the first row and first column of the original,
2463 * full, image which appears in a given pass. 'pass' is in the range 0
2464 * to 6 and the result is in the range 0 to 7.
2465 */
2466#define PNG_PASS_START_ROW(pass) (((1&~(pass))<<(3-((pass)>>1)))&7)
2467#define PNG_PASS_START_COL(pass) (((1& (pass))<<(3-(((pass)+1)>>1)))&7)
2468
2469/* A macro to return the offset between pixels in the output row for a pair of
2470 * pixels in the input - effectively the inverse of the 'COL_SHIFT' macro that
2471 * follows. Note that ROW_OFFSET is the offset from one row to the next whereas
2472 * COL_OFFSET is from one column to the next, within a row.
2473 */
2474#define PNG_PASS_ROW_OFFSET(pass) ((pass)>2?(8>>(((pass)-1)>>1)):8)
2475#define PNG_PASS_COL_OFFSET(pass) (1<<((7-(pass))>>1))
2476
2477/* Two macros to help evaluate the number of rows or columns in each
2478 * pass. This is expressed as a shift - effectively log2 of the number or
2479 * rows or columns in each 8x8 tile of the original image.
2480 */
2481#define PNG_PASS_ROW_SHIFT(pass) ((pass)>2?(8-(pass))>>1:3)
2482#define PNG_PASS_COL_SHIFT(pass) ((pass)>1?(7-(pass))>>1:3)
2483
2484/* Hence two macros to determine the number of rows or columns in a given
2485 * pass of an image given its height or width. In fact these macros may
2486 * return non-zero even though the sub-image is empty, because the other
2487 * dimension may be empty for a small image.
2488 */
2489#define PNG_PASS_ROWS(height, pass) (((height)+(((1<<PNG_PASS_ROW_SHIFT(pass))\
2490 -1)-PNG_PASS_START_ROW(pass)))>>PNG_PASS_ROW_SHIFT(pass))
2491#define PNG_PASS_COLS(width, pass) (((width)+(((1<<PNG_PASS_COL_SHIFT(pass))\
2492 -1)-PNG_PASS_START_COL(pass)))>>PNG_PASS_COL_SHIFT(pass))
2493
2494/* For the reader row callbacks (both progressive and sequential) it is
2495 * necessary to find the row in the output image given a row in an interlaced
2496 * image, so two more macros:
2497 */
2498#define PNG_ROW_FROM_PASS_ROW(y_in, pass) \
2499 (((y_in)<<PNG_PASS_ROW_SHIFT(pass))+PNG_PASS_START_ROW(pass))
2500#define PNG_COL_FROM_PASS_COL(x_in, pass) \
2501 (((x_in)<<PNG_PASS_COL_SHIFT(pass))+PNG_PASS_START_COL(pass))
2502
2503/* Two macros which return a boolean (0 or 1) saying whether the given row
2504 * or column is in a particular pass. These use a common utility macro that
2505 * returns a mask for a given pass - the offset 'off' selects the row or
2506 * column version. The mask has the appropriate bit set for each column in
2507 * the tile.
2508 */
2509#define PNG_PASS_MASK(pass,off) ( \
2510 ((0x110145AF>>(((7-(off))-(pass))<<2)) & 0xF) | \
2511 ((0x01145AF0>>(((7-(off))-(pass))<<2)) & 0xF0))
2512
2513#define PNG_ROW_IN_INTERLACE_PASS(y, pass) \
2514 ((PNG_PASS_MASK(pass,0) >> ((y)&7)) & 1)
2515#define PNG_COL_IN_INTERLACE_PASS(x, pass) \
2516 ((PNG_PASS_MASK(pass,1) >> ((x)&7)) & 1)
2517
2518#ifdef PNG_READ_COMPOSITE_NODIV_SUPPORTED
2519/* With these routines we avoid an integer divide, which will be slower on
2520 * most machines. However, it does take more operations than the corresponding
2521 * divide method, so it may be slower on a few RISC systems. There are two
2522 * shifts (by 8 or 16 bits) and an addition, versus a single integer divide.
2523 *
2524 * Note that the rounding factors are NOT supposed to be the same! 128 and
2525 * 32768 are correct for the NODIV code; 127 and 32767 are correct for the
2526 * standard method.
2527 *
2528 * [Optimized code by Greg Roelofs and Mark Adler...blame us for bugs. :-) ]
2529 */
2530
2531 /* fg and bg should be in `gamma 1.0' space; alpha is the opacity */
2532
2533# define png_composite(composite, fg, alpha, bg) \
2534 { \
2535 png_uint_16 temp = (png_uint_16)((png_uint_16)(fg) \
2536 * (png_uint_16)(alpha) \
2537 + (png_uint_16)(bg)*(png_uint_16)(255 \
2538 - (png_uint_16)(alpha)) + 128); \
2539 (composite) = (png_byte)(((temp + (temp >> 8)) >> 8) & 0xff); \
2540 }
2541
2542# define png_composite_16(composite, fg, alpha, bg) \
2543 { \
2544 png_uint_32 temp = (png_uint_32)((png_uint_32)(fg) \
2545 * (png_uint_32)(alpha) \
2546 + (png_uint_32)(bg)*(65535 \
2547 - (png_uint_32)(alpha)) + 32768); \
2548 (composite) = (png_uint_16)(0xffff & ((temp + (temp >> 16)) >> 16)); \
2549 }
2550
2551#else /* Standard method using integer division */
2552
2553# define png_composite(composite, fg, alpha, bg) \
2554 (composite) = \
2555 (png_byte)(0xff & (((png_uint_16)(fg) * (png_uint_16)(alpha) + \
2556 (png_uint_16)(bg) * (png_uint_16)(255 - (png_uint_16)(alpha)) + \
2557 127) / 255))
2558
2559# define png_composite_16(composite, fg, alpha, bg) \
2560 (composite) = \
2561 (png_uint_16)(0xffff & (((png_uint_32)(fg) * (png_uint_32)(alpha) + \
2562 (png_uint_32)(bg)*(png_uint_32)(65535 - (png_uint_32)(alpha)) + \
2563 32767) / 65535))
2564#endif /* READ_COMPOSITE_NODIV */
2565
2566#ifdef PNG_READ_INT_FUNCTIONS_SUPPORTED
2567PNG_EXPORT(201, png_uint_32, png_get_uint_32, (png_const_bytep buf));
2568PNG_EXPORT(202, png_uint_16, png_get_uint_16, (png_const_bytep buf));
2569PNG_EXPORT(203, png_int_32, png_get_int_32, (png_const_bytep buf));
2570#endif
2571
2572PNG_EXPORT(204, png_uint_32, png_get_uint_31, (png_const_structrp png_ptr,
2573 png_const_bytep buf));
2574/* No png_get_int_16 -- may be added if there's a real need for it. */
2575
2576/* Place a 32-bit number into a buffer in PNG byte order (big-endian). */
2577#ifdef PNG_WRITE_INT_FUNCTIONS_SUPPORTED
2578PNG_EXPORT(205, void, png_save_uint_32, (png_bytep buf, png_uint_32 i));
2579#endif
2580#ifdef PNG_SAVE_INT_32_SUPPORTED
2581PNG_EXPORT(206, void, png_save_int_32, (png_bytep buf, png_int_32 i));
2582#endif
2583
2584/* Place a 16-bit number into a buffer in PNG byte order.
2585 * The parameter is declared unsigned int, not png_uint_16,
2586 * just to avoid potential problems on pre-ANSI C compilers.
2587 */
2588#ifdef PNG_WRITE_INT_FUNCTIONS_SUPPORTED
2589PNG_EXPORT(207, void, png_save_uint_16, (png_bytep buf, unsigned int i));
2590/* No png_save_int_16 -- may be added if there's a real need for it. */
2591#endif
2592
2593#ifdef PNG_USE_READ_MACROS
2594/* Inline macros to do direct reads of bytes from the input buffer.
2595 * The png_get_int_32() routine assumes we are using two's complement
2596 * format for negative values, which is almost certainly true.
2597 */
2598# define PNG_get_uint_32(buf) \
2599 (((png_uint_32)(*(buf)) << 24) + \
2600 ((png_uint_32)(*((buf) + 1)) << 16) + \
2601 ((png_uint_32)(*((buf) + 2)) << 8) + \
2602 ((png_uint_32)(*((buf) + 3))))
2603
2604 /* From libpng-1.4.0 until 1.4.4, the png_get_uint_16 macro (but not the
2605 * function) incorrectly returned a value of type png_uint_32.
2606 */
2607# define PNG_get_uint_16(buf) \
2608 ((png_uint_16) \
2609 (((unsigned int)(*(buf)) << 8) + \
2610 ((unsigned int)(*((buf) + 1)))))
2611
2612# define PNG_get_int_32(buf) \
2613 ((png_int_32)((*(buf) & 0x80) \
2614 ? -((png_int_32)(((png_get_uint_32(buf)^0xffffffffU)+1U)&0x7fffffffU)) \
2615 : (png_int_32)png_get_uint_32(buf)))
2616
2617/* If PNG_PREFIX is defined the same thing as below happens in pnglibconf.h,
2618 * but defining a macro name prefixed with PNG_PREFIX.
2619 */
2620# ifndef PNG_PREFIX
2621# define png_get_uint_32(buf) PNG_get_uint_32(buf)
2622# define png_get_uint_16(buf) PNG_get_uint_16(buf)
2623# define png_get_int_32(buf) PNG_get_int_32(buf)
2624# endif
2625#else
2626# ifdef PNG_PREFIX
2627 /* No macros; revert to the (redefined) function */
2628# define PNG_get_uint_32 (png_get_uint_32)
2629# define PNG_get_uint_16 (png_get_uint_16)
2630# define PNG_get_int_32 (png_get_int_32)
2631# endif
2632#endif
2633
2634#ifdef PNG_CHECK_FOR_INVALID_INDEX_SUPPORTED
2635PNG_EXPORT(242, void, png_set_check_for_invalid_index,
2636 (png_structrp png_ptr, int allowed));
2637# ifdef PNG_GET_PALETTE_MAX_SUPPORTED
2638PNG_EXPORT(243, int, png_get_palette_max, (png_const_structp png_ptr,
2639 png_const_infop info_ptr));
2640# endif
2641#endif /* CHECK_FOR_INVALID_INDEX */
2642
2643/*******************************************************************************
2644 * Section 5: SIMPLIFIED API
2645 *******************************************************************************
2646 *
2647 * Please read the documentation in libpng-manual.txt (TODO: write said
2648 * documentation) if you don't understand what follows.
2649 *
2650 * The simplified API hides the details of both libpng and the PNG file format
2651 * itself. It allows PNG files to be read into a very limited number of
2652 * in-memory bitmap formats or to be written from the same formats. If these
2653 * formats do not accommodate your needs then you can, and should, use the more
2654 * sophisticated APIs above - these support a wide variety of in-memory formats
2655 * and a wide variety of sophisticated transformations to those formats as well
2656 * as a wide variety of APIs to manipulate ancillary information.
2657 *
2658 * To read a PNG file using the simplified API:
2659 *
2660 * 1) Declare a 'png_image' structure (see below) on the stack, set the
2661 * version field to PNG_IMAGE_VERSION and the 'opaque' pointer to NULL
2662 * (this is REQUIRED, your program may crash if you don't do it.)
2663 * 2) Call the appropriate png_image_begin_read... function.
2664 * 3) Set the png_image 'format' member to the required sample format.
2665 * 4) Allocate a buffer for the image and, if required, the color-map.
2666 * 5) Call png_image_finish_read to read the image and, if required, the
2667 * color-map into your buffers.
2668 *
2669 * There are no restrictions on the format of the PNG input itself; all valid
2670 * color types, bit depths, and interlace methods are acceptable, and the
2671 * input image is transformed as necessary to the requested in-memory format
2672 * during the png_image_finish_read() step. The only caveat is that if you
2673 * request a color-mapped image from a PNG that is full-color or makes
2674 * complex use of an alpha channel the transformation is extremely lossy and the
2675 * result may look terrible.
2676 *
2677 * To write a PNG file using the simplified API:
2678 *
2679 * 1) Declare a 'png_image' structure on the stack and memset() it to all zero.
2680 * 2) Initialize the members of the structure that describe the image, setting
2681 * the 'format' member to the format of the image samples.
2682 * 3) Call the appropriate png_image_write... function with a pointer to the
2683 * image and, if necessary, the color-map to write the PNG data.
2684 *
2685 * png_image is a structure that describes the in-memory format of an image
2686 * when it is being read or defines the in-memory format of an image that you
2687 * need to write:
2688 */
2689#if defined(PNG_SIMPLIFIED_READ_SUPPORTED) || \
2690 defined(PNG_SIMPLIFIED_WRITE_SUPPORTED)
2691
2692#define PNG_IMAGE_VERSION 1
2693
2694typedef struct png_control *png_controlp;
2695typedef struct
2696{
2697 png_controlp opaque; /* Initialize to NULL, free with png_image_free */
2698 png_uint_32 version; /* Set to PNG_IMAGE_VERSION */
2699 png_uint_32 width; /* Image width in pixels (columns) */
2700 png_uint_32 height; /* Image height in pixels (rows) */
2701 png_uint_32 format; /* Image format as defined below */
2702 png_uint_32 flags; /* A bit mask containing informational flags */
2703 png_uint_32 colormap_entries;
2704 /* Number of entries in the color-map */
2705
2706 /* In the event of an error or warning the following field will be set to a
2707 * non-zero value and the 'message' field will contain a '\0' terminated
2708 * string with the libpng error or warning message. If both warnings and
2709 * an error were encountered, only the error is recorded. If there
2710 * are multiple warnings, only the first one is recorded.
2711 *
2712 * The upper 30 bits of this value are reserved, the low two bits contain
2713 * a value as follows:
2714 */
2715# define PNG_IMAGE_WARNING 1
2716# define PNG_IMAGE_ERROR 2
2717 /*
2718 * The result is a two-bit code such that a value more than 1 indicates
2719 * a failure in the API just called:
2720 *
2721 * 0 - no warning or error
2722 * 1 - warning
2723 * 2 - error
2724 * 3 - error preceded by warning
2725 */
2726# define PNG_IMAGE_FAILED(png_cntrl) ((((png_cntrl).warning_or_error)&0x03)>1)
2727
2728 png_uint_32 warning_or_error;
2729
2730 char message[64];
2731} png_image, *png_imagep;
2732
2733/* The samples of the image have one to four channels whose components have
2734 * original values in the range 0 to 1.0:
2735 *
2736 * 1: A single gray or luminance channel (G).
2737 * 2: A gray/luminance channel and an alpha channel (GA).
2738 * 3: Three red, green, blue color channels (RGB).
2739 * 4: Three color channels and an alpha channel (RGBA).
2740 *
2741 * The components are encoded in one of two ways:
2742 *
2743 * a) As a small integer, value 0..255, contained in a single byte. For the
2744 * alpha channel the original value is simply value/255. For the color or
2745 * luminance channels the value is encoded according to the sRGB specification
2746 * and matches the 8-bit format expected by typical display devices.
2747 *
2748 * The color/gray channels are not scaled (pre-multiplied) by the alpha
2749 * channel and are suitable for passing to color management software.
2750 *
2751 * b) As a value in the range 0..65535, contained in a 2-byte integer. All
2752 * channels can be converted to the original value by dividing by 65535; all
2753 * channels are linear. Color channels use the RGB encoding (RGB end-points) of
2754 * the sRGB specification. This encoding is identified by the
2755 * PNG_FORMAT_FLAG_LINEAR flag below.
2756 *
2757 * When the simplified API needs to convert between sRGB and linear colorspaces,
2758 * the actual sRGB transfer curve defined in the sRGB specification (see the
2759 * article at <https://en.wikipedia.org/wiki/SRGB>) is used, not the gamma=1/2.2
2760 * approximation used elsewhere in libpng.
2761 *
2762 * When an alpha channel is present it is expected to denote pixel coverage
2763 * of the color or luminance channels and is returned as an associated alpha
2764 * channel: the color/gray channels are scaled (pre-multiplied) by the alpha
2765 * value.
2766 *
2767 * The samples are either contained directly in the image data, between 1 and 8
2768 * bytes per pixel according to the encoding, or are held in a color-map indexed
2769 * by bytes in the image data. In the case of a color-map the color-map entries
2770 * are individual samples, encoded as above, and the image data has one byte per
2771 * pixel to select the relevant sample from the color-map.
2772 */
2773
2774/* PNG_FORMAT_*
2775 *
2776 * #defines to be used in png_image::format. Each #define identifies a
2777 * particular layout of sample data and, if present, alpha values. There are
2778 * separate defines for each of the two component encodings.
2779 *
2780 * A format is built up using single bit flag values. All combinations are
2781 * valid. Formats can be built up from the flag values or you can use one of
2782 * the predefined values below. When testing formats always use the FORMAT_FLAG
2783 * macros to test for individual features - future versions of the library may
2784 * add new flags.
2785 *
2786 * When reading or writing color-mapped images the format should be set to the
2787 * format of the entries in the color-map then png_image_{read,write}_colormap
2788 * called to read or write the color-map and set the format correctly for the
2789 * image data. Do not set the PNG_FORMAT_FLAG_COLORMAP bit directly!
2790 *
2791 * NOTE: libpng can be built with particular features disabled. If you see
2792 * compiler errors because the definition of one of the following flags has been
2793 * compiled out it is because libpng does not have the required support. It is
2794 * possible, however, for the libpng configuration to enable the format on just
2795 * read or just write; in that case you may see an error at run time. You can
2796 * guard against this by checking for the definition of the appropriate
2797 * "_SUPPORTED" macro, one of:
2798 *
2799 * PNG_SIMPLIFIED_{READ,WRITE}_{BGR,AFIRST}_SUPPORTED
2800 */
2801#define PNG_FORMAT_FLAG_ALPHA 0x01U /* format with an alpha channel */
2802#define PNG_FORMAT_FLAG_COLOR 0x02U /* color format: otherwise grayscale */
2803#define PNG_FORMAT_FLAG_LINEAR 0x04U /* 2-byte channels else 1-byte */
2804#define PNG_FORMAT_FLAG_COLORMAP 0x08U /* image data is color-mapped */
2805
2806#ifdef PNG_FORMAT_BGR_SUPPORTED
2807# define PNG_FORMAT_FLAG_BGR 0x10U /* BGR colors, else order is RGB */
2808#endif
2809
2810#ifdef PNG_FORMAT_AFIRST_SUPPORTED
2811# define PNG_FORMAT_FLAG_AFIRST 0x20U /* alpha channel comes first */
2812#endif
2813
2814#define PNG_FORMAT_FLAG_ASSOCIATED_ALPHA 0x40U /* alpha channel is associated */
2815
2816/* Commonly used formats have predefined macros.
2817 *
2818 * First the single byte (sRGB) formats:
2819 */
2820#define PNG_FORMAT_GRAY 0
2821#define PNG_FORMAT_GA PNG_FORMAT_FLAG_ALPHA
2822#define PNG_FORMAT_AG (PNG_FORMAT_GA|PNG_FORMAT_FLAG_AFIRST)
2823#define PNG_FORMAT_RGB PNG_FORMAT_FLAG_COLOR
2824#define PNG_FORMAT_BGR (PNG_FORMAT_FLAG_COLOR|PNG_FORMAT_FLAG_BGR)
2825#define PNG_FORMAT_RGBA (PNG_FORMAT_RGB|PNG_FORMAT_FLAG_ALPHA)
2826#define PNG_FORMAT_ARGB (PNG_FORMAT_RGBA|PNG_FORMAT_FLAG_AFIRST)
2827#define PNG_FORMAT_BGRA (PNG_FORMAT_BGR|PNG_FORMAT_FLAG_ALPHA)
2828#define PNG_FORMAT_ABGR (PNG_FORMAT_BGRA|PNG_FORMAT_FLAG_AFIRST)
2829
2830/* Then the linear 2-byte formats. When naming these "Y" is used to
2831 * indicate a luminance (gray) channel.
2832 */
2833#define PNG_FORMAT_LINEAR_Y PNG_FORMAT_FLAG_LINEAR
2834#define PNG_FORMAT_LINEAR_Y_ALPHA (PNG_FORMAT_FLAG_LINEAR|PNG_FORMAT_FLAG_ALPHA)
2835#define PNG_FORMAT_LINEAR_RGB (PNG_FORMAT_FLAG_LINEAR|PNG_FORMAT_FLAG_COLOR)
2836#define PNG_FORMAT_LINEAR_RGB_ALPHA \
2837 (PNG_FORMAT_FLAG_LINEAR|PNG_FORMAT_FLAG_COLOR|PNG_FORMAT_FLAG_ALPHA)
2838
2839/* With color-mapped formats the image data is one byte for each pixel, the byte
2840 * is an index into the color-map which is formatted as above. To obtain a
2841 * color-mapped format it is sufficient just to add the PNG_FOMAT_FLAG_COLORMAP
2842 * to one of the above definitions, or you can use one of the definitions below.
2843 */
2844#define PNG_FORMAT_RGB_COLORMAP (PNG_FORMAT_RGB|PNG_FORMAT_FLAG_COLORMAP)
2845#define PNG_FORMAT_BGR_COLORMAP (PNG_FORMAT_BGR|PNG_FORMAT_FLAG_COLORMAP)
2846#define PNG_FORMAT_RGBA_COLORMAP (PNG_FORMAT_RGBA|PNG_FORMAT_FLAG_COLORMAP)
2847#define PNG_FORMAT_ARGB_COLORMAP (PNG_FORMAT_ARGB|PNG_FORMAT_FLAG_COLORMAP)
2848#define PNG_FORMAT_BGRA_COLORMAP (PNG_FORMAT_BGRA|PNG_FORMAT_FLAG_COLORMAP)
2849#define PNG_FORMAT_ABGR_COLORMAP (PNG_FORMAT_ABGR|PNG_FORMAT_FLAG_COLORMAP)
2850
2851/* PNG_IMAGE macros
2852 *
2853 * These are convenience macros to derive information from a png_image
2854 * structure. The PNG_IMAGE_SAMPLE_ macros return values appropriate to the
2855 * actual image sample values - either the entries in the color-map or the
2856 * pixels in the image. The PNG_IMAGE_PIXEL_ macros return corresponding values
2857 * for the pixels and will always return 1 for color-mapped formats. The
2858 * remaining macros return information about the rows in the image and the
2859 * complete image.
2860 *
2861 * NOTE: All the macros that take a png_image::format parameter are compile time
2862 * constants if the format parameter is, itself, a constant. Therefore these
2863 * macros can be used in array declarations and case labels where required.
2864 * Similarly the macros are also pre-processor constants (sizeof is not used) so
2865 * they can be used in #if tests.
2866 *
2867 * First the information about the samples.
2868 */
2869#define PNG_IMAGE_SAMPLE_CHANNELS(fmt)\
2870 (((fmt)&(PNG_FORMAT_FLAG_COLOR|PNG_FORMAT_FLAG_ALPHA))+1)
2871 /* Return the total number of channels in a given format: 1..4 */
2872
2873#define PNG_IMAGE_SAMPLE_COMPONENT_SIZE(fmt)\
2874 ((((fmt) & PNG_FORMAT_FLAG_LINEAR) >> 2)+1)
2875 /* Return the size in bytes of a single component of a pixel or color-map
2876 * entry (as appropriate) in the image: 1 or 2.
2877 */
2878
2879#define PNG_IMAGE_SAMPLE_SIZE(fmt)\
2880 (PNG_IMAGE_SAMPLE_CHANNELS(fmt) * PNG_IMAGE_SAMPLE_COMPONENT_SIZE(fmt))
2881 /* This is the size of the sample data for one sample. If the image is
2882 * color-mapped it is the size of one color-map entry (and image pixels are
2883 * one byte in size), otherwise it is the size of one image pixel.
2884 */
2885
2886#define PNG_IMAGE_MAXIMUM_COLORMAP_COMPONENTS(fmt)\
2887 (PNG_IMAGE_SAMPLE_CHANNELS(fmt) * 256)
2888 /* The maximum size of the color-map required by the format expressed in a
2889 * count of components. This can be used to compile-time allocate a
2890 * color-map:
2891 *
2892 * png_uint_16 colormap[PNG_IMAGE_MAXIMUM_COLORMAP_COMPONENTS(linear_fmt)];
2893 *
2894 * png_byte colormap[PNG_IMAGE_MAXIMUM_COLORMAP_COMPONENTS(sRGB_fmt)];
2895 *
2896 * Alternatively use the PNG_IMAGE_COLORMAP_SIZE macro below to use the
2897 * information from one of the png_image_begin_read_ APIs and dynamically
2898 * allocate the required memory.
2899 */
2900
2901/* Corresponding information about the pixels */
2902#define PNG_IMAGE_PIXEL_(test,fmt)\
2903 (((fmt)&PNG_FORMAT_FLAG_COLORMAP)?1:test(fmt))
2904
2905#define PNG_IMAGE_PIXEL_CHANNELS(fmt)\
2906 PNG_IMAGE_PIXEL_(PNG_IMAGE_SAMPLE_CHANNELS,fmt)
2907 /* The number of separate channels (components) in a pixel; 1 for a
2908 * color-mapped image.
2909 */
2910
2911#define PNG_IMAGE_PIXEL_COMPONENT_SIZE(fmt)\
2912 PNG_IMAGE_PIXEL_(PNG_IMAGE_SAMPLE_COMPONENT_SIZE,fmt)
2913 /* The size, in bytes, of each component in a pixel; 1 for a color-mapped
2914 * image.
2915 */
2916
2917#define PNG_IMAGE_PIXEL_SIZE(fmt) PNG_IMAGE_PIXEL_(PNG_IMAGE_SAMPLE_SIZE,fmt)
2918 /* The size, in bytes, of a complete pixel; 1 for a color-mapped image. */
2919
2920/* Information about the whole row, or whole image */
2921#define PNG_IMAGE_ROW_STRIDE(image)\
2922 (PNG_IMAGE_PIXEL_CHANNELS((image).format) * (image).width)
2923 /* Return the total number of components in a single row of the image; this
2924 * is the minimum 'row stride', the minimum count of components between each
2925 * row. For a color-mapped image this is the minimum number of bytes in a
2926 * row.
2927 *
2928 * WARNING: this macro overflows for some images with more than one component
2929 * and very large image widths. libpng will refuse to process an image where
2930 * this macro would overflow.
2931 */
2932
2933#define PNG_IMAGE_BUFFER_SIZE(image, row_stride)\
2934 (PNG_IMAGE_PIXEL_COMPONENT_SIZE((image).format)*(image).height*(row_stride))
2935 /* Return the size, in bytes, of an image buffer given a png_image and a row
2936 * stride - the number of components to leave space for in each row.
2937 *
2938 * WARNING: this macro overflows a 32-bit integer for some large PNG images,
2939 * libpng will refuse to process an image where such an overflow would occur.
2940 */
2941
2942#define PNG_IMAGE_SIZE(image)\
2943 PNG_IMAGE_BUFFER_SIZE(image, PNG_IMAGE_ROW_STRIDE(image))
2944 /* Return the size, in bytes, of the image in memory given just a png_image;
2945 * the row stride is the minimum stride required for the image.
2946 */
2947
2948#define PNG_IMAGE_COLORMAP_SIZE(image)\
2949 (PNG_IMAGE_SAMPLE_SIZE((image).format) * (image).colormap_entries)
2950 /* Return the size, in bytes, of the color-map of this image. If the image
2951 * format is not a color-map format this will return a size sufficient for
2952 * 256 entries in the given format; check PNG_FORMAT_FLAG_COLORMAP if
2953 * you don't want to allocate a color-map in this case.
2954 */
2955
2956/* PNG_IMAGE_FLAG_*
2957 *
2958 * Flags containing additional information about the image are held in the
2959 * 'flags' field of png_image.
2960 */
2961#define PNG_IMAGE_FLAG_COLORSPACE_NOT_sRGB 0x01
2962 /* This indicates that the RGB values of the in-memory bitmap do not
2963 * correspond to the red, green and blue end-points defined by sRGB.
2964 */
2965
2966#define PNG_IMAGE_FLAG_FAST 0x02
2967 /* On write emphasise speed over compression; the resultant PNG file will be
2968 * larger but will be produced significantly faster, particular for large
2969 * images. Do not use this option for images which will be distributed, only
2970 * used it when producing intermediate files that will be read back in
2971 * repeatedly. For a typical 24-bit image the option will double the read
2972 * speed at the cost of increasing the image size by 25%, however for many
2973 * more compressible images the PNG file can be 10 times larger with only a
2974 * slight speed gain.
2975 */
2976
2977#define PNG_IMAGE_FLAG_16BIT_sRGB 0x04
2978 /* On read if the image is a 16-bit per component image and there is no gAMA
2979 * or sRGB chunk assume that the components are sRGB encoded. Notice that
2980 * images output by the simplified API always have gamma information; setting
2981 * this flag only affects the interpretation of 16-bit images from an
2982 * external source. It is recommended that the application expose this flag
2983 * to the user; the user can normally easily recognize the difference between
2984 * linear and sRGB encoding. This flag has no effect on write - the data
2985 * passed to the write APIs must have the correct encoding (as defined
2986 * above.)
2987 *
2988 * If the flag is not set (the default) input 16-bit per component data is
2989 * assumed to be linear.
2990 *
2991 * NOTE: the flag can only be set after the png_image_begin_read_ call,
2992 * because that call initializes the 'flags' field.
2993 */
2994
2995#ifdef PNG_SIMPLIFIED_READ_SUPPORTED
2996/* READ APIs
2997 * ---------
2998 *
2999 * The png_image passed to the read APIs must have been initialized by setting
3000 * the png_controlp field 'opaque' to NULL (or, safer, memset the whole thing.)
3001 */
3002#ifdef PNG_STDIO_SUPPORTED
3003PNG_EXPORT(234, int, png_image_begin_read_from_file, (png_imagep image,
3004 const char *file_name));
3005 /* The named file is opened for read and the image header is filled in
3006 * from the PNG header in the file.
3007 */
3008
3009PNG_EXPORT(235, int, png_image_begin_read_from_stdio, (png_imagep image,
3010 FILE* file));
3011 /* The PNG header is read from the stdio FILE object. */
3012#endif /* STDIO */
3013
3014PNG_EXPORT(236, int, png_image_begin_read_from_memory, (png_imagep image,
3015 png_const_voidp memory, size_t size));
3016 /* The PNG header is read from the given memory buffer. */
3017
3018PNG_EXPORT(237, int, png_image_finish_read, (png_imagep image,
3019 png_const_colorp background, void *buffer, png_int_32 row_stride,
3020 void *colormap));
3021 /* Finish reading the image into the supplied buffer and clean up the
3022 * png_image structure.
3023 *
3024 * row_stride is the step, in byte or 2-byte units as appropriate,
3025 * between adjacent rows. A positive stride indicates that the top-most row
3026 * is first in the buffer - the normal top-down arrangement. A negative
3027 * stride indicates that the bottom-most row is first in the buffer.
3028 *
3029 * background need only be supplied if an alpha channel must be removed from
3030 * a png_byte format and the removal is to be done by compositing on a solid
3031 * color; otherwise it may be NULL and any composition will be done directly
3032 * onto the buffer. The value is an sRGB color to use for the background,
3033 * for grayscale output the green channel is used.
3034 *
3035 * background must be supplied when an alpha channel must be removed from a
3036 * single byte color-mapped output format, in other words if:
3037 *
3038 * 1) The original format from png_image_begin_read_from_* had
3039 * PNG_FORMAT_FLAG_ALPHA set.
3040 * 2) The format set by the application does not.
3041 * 3) The format set by the application has PNG_FORMAT_FLAG_COLORMAP set and
3042 * PNG_FORMAT_FLAG_LINEAR *not* set.
3043 *
3044 * For linear output removing the alpha channel is always done by compositing
3045 * on black and background is ignored.
3046 *
3047 * colormap must be supplied when PNG_FORMAT_FLAG_COLORMAP is set. It must
3048 * be at least the size (in bytes) returned by PNG_IMAGE_COLORMAP_SIZE.
3049 * image->colormap_entries will be updated to the actual number of entries
3050 * written to the colormap; this may be less than the original value.
3051 */
3052
3053PNG_EXPORT(238, void, png_image_free, (png_imagep image));
3054 /* Free any data allocated by libpng in image->opaque, setting the pointer to
3055 * NULL. May be called at any time after the structure is initialized.
3056 */
3057#endif /* SIMPLIFIED_READ */
3058
3059#ifdef PNG_SIMPLIFIED_WRITE_SUPPORTED
3060/* WRITE APIS
3061 * ----------
3062 * For write you must initialize a png_image structure to describe the image to
3063 * be written. To do this use memset to set the whole structure to 0 then
3064 * initialize fields describing your image.
3065 *
3066 * version: must be set to PNG_IMAGE_VERSION
3067 * opaque: must be initialized to NULL
3068 * width: image width in pixels
3069 * height: image height in rows
3070 * format: the format of the data (image and color-map) you wish to write
3071 * flags: set to 0 unless one of the defined flags applies; set
3072 * PNG_IMAGE_FLAG_COLORSPACE_NOT_sRGB for color format images where the RGB
3073 * values do not correspond to the colors in sRGB.
3074 * colormap_entries: set to the number of entries in the color-map (0 to 256)
3075 */
3076#ifdef PNG_SIMPLIFIED_WRITE_STDIO_SUPPORTED
3077PNG_EXPORT(239, int, png_image_write_to_file, (png_imagep image,
3078 const char *file, int convert_to_8bit, const void *buffer,
3079 png_int_32 row_stride, const void *colormap));
3080 /* Write the image to the named file. */
3081
3082PNG_EXPORT(240, int, png_image_write_to_stdio, (png_imagep image, FILE *file,
3083 int convert_to_8_bit, const void *buffer, png_int_32 row_stride,
3084 const void *colormap));
3085 /* Write the image to the given (FILE*). */
3086#endif /* SIMPLIFIED_WRITE_STDIO */
3087
3088/* With all write APIs if image is in one of the linear formats with 16-bit
3089 * data then setting convert_to_8_bit will cause the output to be an 8-bit PNG
3090 * gamma encoded according to the sRGB specification, otherwise a 16-bit linear
3091 * encoded PNG file is written.
3092 *
3093 * With color-mapped data formats the colormap parameter point to a color-map
3094 * with at least image->colormap_entries encoded in the specified format. If
3095 * the format is linear the written PNG color-map will be converted to sRGB
3096 * regardless of the convert_to_8_bit flag.
3097 *
3098 * With all APIs row_stride is handled as in the read APIs - it is the spacing
3099 * from one row to the next in component sized units (1 or 2 bytes) and if
3100 * negative indicates a bottom-up row layout in the buffer. If row_stride is
3101 * zero, libpng will calculate it for you from the image width and number of
3102 * channels.
3103 *
3104 * Note that the write API does not support interlacing, sub-8-bit pixels or
3105 * most ancillary chunks. If you need to write text chunks (e.g. for copyright
3106 * notices) you need to use one of the other APIs.
3107 */
3108
3109PNG_EXPORT(245, int, png_image_write_to_memory, (png_imagep image, void *memory,
3110 png_alloc_size_t * PNG_RESTRICT memory_bytes, int convert_to_8_bit,
3111 const void *buffer, png_int_32 row_stride, const void *colormap));
3112 /* Write the image to the given memory buffer. The function both writes the
3113 * whole PNG data stream to *memory and updates *memory_bytes with the count
3114 * of bytes written.
3115 *
3116 * 'memory' may be NULL. In this case *memory_bytes is not read however on
3117 * success the number of bytes which would have been written will still be
3118 * stored in *memory_bytes. On failure *memory_bytes will contain 0.
3119 *
3120 * If 'memory' is not NULL it must point to memory[*memory_bytes] of
3121 * writeable memory.
3122 *
3123 * If the function returns success memory[*memory_bytes] (if 'memory' is not
3124 * NULL) contains the written PNG data. *memory_bytes will always be less
3125 * than or equal to the original value.
3126 *
3127 * If the function returns false and *memory_bytes was not changed an error
3128 * occurred during write. If *memory_bytes was changed, or is not 0 if
3129 * 'memory' was NULL, the write would have succeeded but for the memory
3130 * buffer being too small. *memory_bytes contains the required number of
3131 * bytes and will be bigger that the original value.
3132 */
3133
3134#define png_image_write_get_memory_size(image, size, convert_to_8_bit, buffer,\
3135 row_stride, colormap)\
3136 png_image_write_to_memory(&(image), 0, &(size), convert_to_8_bit, buffer,\
3137 row_stride, colormap)
3138 /* Return the amount of memory in 'size' required to compress this image.
3139 * The png_image structure 'image' must be filled in as in the above
3140 * function and must not be changed before the actual write call, the buffer
3141 * and all other parameters must also be identical to that in the final
3142 * write call. The 'size' variable need not be initialized.
3143 *
3144 * NOTE: the macro returns true/false, if false is returned 'size' will be
3145 * set to zero and the write failed and probably will fail if tried again.
3146 */
3147
3148/* You can pre-allocate the buffer by making sure it is of sufficient size
3149 * regardless of the amount of compression achieved. The buffer size will
3150 * always be bigger than the original image and it will never be filled. The
3151 * following macros are provided to assist in allocating the buffer.
3152 */
3153#define PNG_IMAGE_DATA_SIZE(image) (PNG_IMAGE_SIZE(image)+(image).height)
3154 /* The number of uncompressed bytes in the PNG byte encoding of the image;
3155 * uncompressing the PNG IDAT data will give this number of bytes.
3156 *
3157 * NOTE: while PNG_IMAGE_SIZE cannot overflow for an image in memory this
3158 * macro can because of the extra bytes used in the PNG byte encoding. You
3159 * need to avoid this macro if your image size approaches 2^30 in width or
3160 * height. The same goes for the remainder of these macros; they all produce
3161 * bigger numbers than the actual in-memory image size.
3162 */
3163#ifndef PNG_ZLIB_MAX_SIZE
3164# define PNG_ZLIB_MAX_SIZE(b) ((b)+(((b)+7U)>>3)+(((b)+63U)>>6)+11U)
3165 /* An upper bound on the number of compressed bytes given 'b' uncompressed
3166 * bytes. This is based on deflateBounds() in zlib; different
3167 * implementations of zlib compression may conceivably produce more data so
3168 * if your zlib implementation is not zlib itself redefine this macro
3169 * appropriately.
3170 */
3171#endif
3172
3173#define PNG_IMAGE_COMPRESSED_SIZE_MAX(image)\
3174 PNG_ZLIB_MAX_SIZE((png_alloc_size_t)PNG_IMAGE_DATA_SIZE(image))
3175 /* An upper bound on the size of the data in the PNG IDAT chunks. */
3176
3177#define PNG_IMAGE_PNG_SIZE_MAX_(image, image_size)\
3178 ((8U/*sig*/+25U/*IHDR*/+16U/*gAMA*/+44U/*cHRM*/+12U/*IEND*/+\
3179 (((image).format&PNG_FORMAT_FLAG_COLORMAP)?/*colormap: PLTE, tRNS*/\
3180 12U+3U*(image).colormap_entries/*PLTE data*/+\
3181 (((image).format&PNG_FORMAT_FLAG_ALPHA)?\
3182 12U/*tRNS*/+(image).colormap_entries:0U):0U)+\
3183 12U)+(12U*((image_size)/PNG_ZBUF_SIZE))/*IDAT*/+(image_size))
3184 /* A helper for the following macro; if your compiler cannot handle the
3185 * following macro use this one with the result of
3186 * PNG_IMAGE_COMPRESSED_SIZE_MAX(image) as the second argument (most
3187 * compilers should handle this just fine.)
3188 */
3189
3190#define PNG_IMAGE_PNG_SIZE_MAX(image)\
3191 PNG_IMAGE_PNG_SIZE_MAX_(image, PNG_IMAGE_COMPRESSED_SIZE_MAX(image))
3192 /* An upper bound on the total length of the PNG data stream for 'image'.
3193 * The result is of type png_alloc_size_t, on 32-bit systems this may
3194 * overflow even though PNG_IMAGE_DATA_SIZE does not overflow; the write will
3195 * run out of buffer space but return a corrected size which should work.
3196 */
3197#endif /* SIMPLIFIED_WRITE */
3198/*******************************************************************************
3199 * END OF SIMPLIFIED API
3200 ******************************************************************************/
3201#endif /* SIMPLIFIED_{READ|WRITE} */
3202
3203/*******************************************************************************
3204 * Section 6: IMPLEMENTATION OPTIONS
3205 *******************************************************************************
3206 *
3207 * Support for arbitrary implementation-specific optimizations. The API allows
3208 * particular options to be turned on or off. 'Option' is the number of the
3209 * option and 'onoff' is 0 (off) or non-0 (on). The value returned is given
3210 * by the PNG_OPTION_ defines below.
3211 *
3212 * HARDWARE: normally hardware capabilities, such as the Intel SSE instructions,
3213 * are detected at run time, however sometimes it may be impossible
3214 * to do this in user mode, in which case it is necessary to discover
3215 * the capabilities in an OS specific way. Such capabilities are
3216 * listed here when libpng has support for them and must be turned
3217 * ON by the application if present.
3218 *
3219 * SOFTWARE: sometimes software optimizations actually result in performance
3220 * decrease on some architectures or systems, or with some sets of
3221 * PNG images. 'Software' options allow such optimizations to be
3222 * selected at run time.
3223 */
3224#ifdef PNG_SET_OPTION_SUPPORTED
3225#ifdef PNG_ARM_NEON_API_SUPPORTED
3226# define PNG_ARM_NEON 0 /* HARDWARE: ARM Neon SIMD instructions supported */
3227#endif
3228#define PNG_MAXIMUM_INFLATE_WINDOW 2 /* SOFTWARE: force maximum window */
3229#define PNG_SKIP_sRGB_CHECK_PROFILE 4 /* SOFTWARE: Check ICC profile for sRGB */
3230#ifdef PNG_MIPS_MSA_API_SUPPORTED
3231# define PNG_MIPS_MSA 6 /* HARDWARE: MIPS Msa SIMD instructions supported */
3232#endif
3233#define PNG_IGNORE_ADLER32 8
3234#ifdef PNG_POWERPC_VSX_API_SUPPORTED
3235# define PNG_POWERPC_VSX 10 /* HARDWARE: PowerPC VSX SIMD instructions supported */
3236#endif
3237#define PNG_OPTION_NEXT 12 /* Next option - numbers must be even */
3238
3239#ifdef PNG_LOONGSON_MMI_API_SUPPORTED
3240# define PNG_LOONGSON_MMI 14 /* HARDWARE: LOONGSON MMI SIMD instructions supported */
3241#endif
3242
3243/* Return values: NOTE: there are four values and 'off' is *not* zero */
3244#define PNG_OPTION_UNSET 0 /* Unset - defaults to off */
3245#define PNG_OPTION_INVALID 1 /* Option number out of range */
3246#define PNG_OPTION_OFF 2
3247#define PNG_OPTION_ON 3
3248
3249PNG_EXPORT(244, int, png_set_option, (png_structrp png_ptr, int option,
3250 int onoff));
3251#endif /* SET_OPTION */
3252
3253/*******************************************************************************
3254 * END OF HARDWARE AND SOFTWARE OPTIONS
3255 ******************************************************************************/
3256#ifdef PNG_APNG_SUPPORTED
3257PNG_EXPORT(250, png_uint_32, png_get_acTL, (png_structp png_ptr,
3258 png_infop info_ptr, png_uint_32 *num_frames, png_uint_32 *num_plays));
3259
3260PNG_EXPORT(251, png_uint_32, png_set_acTL, (png_structp png_ptr,
3261 png_infop info_ptr, png_uint_32 num_frames, png_uint_32 num_plays));
3262
3263PNG_EXPORT(252, png_uint_32, png_get_num_frames, (png_structp png_ptr,
3264 png_infop info_ptr));
3265
3266PNG_EXPORT(253, png_uint_32, png_get_num_plays, (png_structp png_ptr,
3267 png_infop info_ptr));
3268
3269PNG_EXPORT(254, png_uint_32, png_get_next_frame_fcTL,
3270 (png_structp png_ptr, png_infop info_ptr, png_uint_32 *width,
3271 png_uint_32 *height, png_uint_32 *x_offset, png_uint_32 *y_offset,
3272 png_uint_16 *delay_num, png_uint_16 *delay_den, png_byte *dispose_op,
3273 png_byte *blend_op));
3274
3275PNG_EXPORT(255, png_uint_32, png_set_next_frame_fcTL,
3276 (png_structp png_ptr, png_infop info_ptr, png_uint_32 width,
3277 png_uint_32 height, png_uint_32 x_offset, png_uint_32 y_offset,
3278 png_uint_16 delay_num, png_uint_16 delay_den, png_byte dispose_op,
3279 png_byte blend_op));
3280
3281PNG_EXPORT(256, png_uint_32, png_get_next_frame_width,
3282 (png_structp png_ptr, png_infop info_ptr));
3283PNG_EXPORT(257, png_uint_32, png_get_next_frame_height,
3284 (png_structp png_ptr, png_infop info_ptr));
3285PNG_EXPORT(258, png_uint_32, png_get_next_frame_x_offset,
3286 (png_structp png_ptr, png_infop info_ptr));
3287PNG_EXPORT(259, png_uint_32, png_get_next_frame_y_offset,
3288 (png_structp png_ptr, png_infop info_ptr));
3289PNG_EXPORT(260, png_uint_16, png_get_next_frame_delay_num,
3290 (png_structp png_ptr, png_infop info_ptr));
3291PNG_EXPORT(261, png_uint_16, png_get_next_frame_delay_den,
3292 (png_structp png_ptr, png_infop info_ptr));
3293PNG_EXPORT(262, png_byte, png_get_next_frame_dispose_op,
3294 (png_structp png_ptr, png_infop info_ptr));
3295PNG_EXPORT(263, png_byte, png_get_next_frame_blend_op,
3296 (png_structp png_ptr, png_infop info_ptr));
3297PNG_EXPORT(264, png_byte, png_get_first_frame_is_hidden,
3298 (png_structp png_ptr, png_infop info_ptr));
3299PNG_EXPORT(265, png_uint_32, png_set_first_frame_is_hidden,
3300 (png_structp png_ptr, png_infop info_ptr, png_byte is_hidden));
3301
3302#ifdef PNG_READ_APNG_SUPPORTED
3303PNG_EXPORT(266, void, png_read_frame_head, (png_structp png_ptr,
3304 png_infop info_ptr));
3305#ifdef PNG_PROGRESSIVE_READ_SUPPORTED
3306PNG_EXPORT(267, void, png_set_progressive_frame_fn, (png_structp png_ptr,
3307 png_progressive_frame_ptr frame_info_fn,
3308 png_progressive_frame_ptr frame_end_fn));
3309#endif /* PNG_PROGRESSIVE_READ_SUPPORTED */
3310#endif /* PNG_READ_APNG_SUPPORTED */
3311
3312#ifdef PNG_WRITE_APNG_SUPPORTED
3313PNG_EXPORT(268, void, png_write_frame_head, (png_structp png_ptr,
3314 png_infop info_ptr, png_bytepp row_pointers,
3315 png_uint_32 width, png_uint_32 height,
3316 png_uint_32 x_offset, png_uint_32 y_offset,
3317 png_uint_16 delay_num, png_uint_16 delay_den, png_byte dispose_op,
3318 png_byte blend_op));
3319
3320PNG_EXPORT(269, void, png_write_frame_tail, (png_structp png_ptr,
3321 png_infop info_ptr));
3322#endif /* PNG_WRITE_APNG_SUPPORTED */
3323#endif /* PNG_APNG_SUPPORTED */
3324
3325/* Maintainer: Put new public prototypes here ^, in libpng.3, in project
3326 * defs, and in scripts/symbols.def.
3327 */
3328
3329/* The last ordinal number (this is the *last* one already used; the next
3330 * one to use is one more than this.)
3331 */
3332#ifdef PNG_EXPORT_LAST_ORDINAL
3333#ifdef PNG_APNG_SUPPORTED
3334 PNG_EXPORT_LAST_ORDINAL(269);
3335#else
3336 PNG_EXPORT_LAST_ORDINAL(249);
3337#endif /* PNG_APNG_SUPPORTED */
3338#endif
3339
3340#ifdef __cplusplus
3341}
3342#endif
3343
3344#endif /* PNG_VERSION_INFO_ONLY */
3345/* Do not put anything past this line */
3346#endif /* PNG_H */
3347