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1
2/* png.h - header file for PNG reference library
3 *
4 * libpng version 1.2.24 - December 14, 2007
5 * Copyright (c) 1998-2007 Glenn Randers-Pehrson
6 * (Version 0.96 Copyright (c) 1996, 1997 Andreas Dilger)
7 * (Version 0.88 Copyright (c) 1995, 1996 Guy Eric Schalnat, Group 42, Inc.)
8 *
9 * Authors and maintainers:
10 * libpng versions 0.71, May 1995, through 0.88, January 1996: Guy Schalnat
11 * libpng versions 0.89c, June 1996, through 0.96, May 1997: Andreas Dilger
12 * libpng versions 0.97, January 1998, through 1.2.24 - December 14, 2007: Glenn
13 * See also "Contributing Authors", below.
14 *
15 * Note about libpng version numbers:
16 *
17 * Due to various miscommunications, unforeseen code incompatibilities
18 * and occasional factors outside the authors' control, version numbering
19 * on the library has not always been consistent and straightforward.
20 * The following table summarizes matters since version 0.89c, which was
21 * the first widely used release:
22 *
23 * source png.h png.h shared-lib
24 * version string int version
25 * ------- ------ ----- ----------
26 * 0.89c "1.0 beta 3" 0.89 89 1.0.89
27 * 0.90 "1.0 beta 4" 0.90 90 0.90 [should have been 2.0.90]
28 * 0.95 "1.0 beta 5" 0.95 95 0.95 [should have been 2.0.95]
29 * 0.96 "1.0 beta 6" 0.96 96 0.96 [should have been 2.0.96]
30 * 0.97b "1.00.97 beta 7" 1.00.97 97 1.0.1 [should have been 2.0.97]
31 * 0.97c 0.97 97 2.0.97
32 * 0.98 0.98 98 2.0.98
33 * 0.99 0.99 98 2.0.99
34 * 0.99a-m 0.99 99 2.0.99
35 * 1.00 1.00 100 2.1.0 [100 should be 10000]
36 * 1.0.0 (from here on, the 100 2.1.0 [100 should be 10000]
37 * 1.0.1 png.h string is 10001 2.1.0
38 * 1.0.1a-e identical to the 10002 from here on, the shared library
39 * 1.0.2 source version) 10002 is 2.V where V is the source code
40 * 1.0.2a-b 10003 version, except as noted.
41 * 1.0.3 10003
42 * 1.0.3a-d 10004
43 * 1.0.4 10004
44 * 1.0.4a-f 10005
45 * 1.0.5 (+ 2 patches) 10005
46 * 1.0.5a-d 10006
47 * 1.0.5e-r 10100 (not source compatible)
48 * 1.0.5s-v 10006 (not binary compatible)
49 * 1.0.6 (+ 3 patches) 10006 (still binary incompatible)
50 * 1.0.6d-f 10007 (still binary incompatible)
51 * 1.0.6g 10007
52 * 1.0.6h 10007 10.6h (testing xy.z so-numbering)
53 * 1.0.6i 10007 10.6i
54 * 1.0.6j 10007 2.1.0.6j (incompatible with 1.0.0)
55 * 1.0.7beta11-14 DLLNUM 10007 2.1.0.7beta11-14 (binary compatible)
56 * 1.0.7beta15-18 1 10007 2.1.0.7beta15-18 (binary compatible)
57 * 1.0.7rc1-2 1 10007 2.1.0.7rc1-2 (binary compatible)
58 * 1.0.7 1 10007 (still compatible)
59 * 1.0.8beta1-4 1 10008 2.1.0.8beta1-4
60 * 1.0.8rc1 1 10008 2.1.0.8rc1
61 * 1.0.8 1 10008 2.1.0.8
62 * 1.0.9beta1-6 1 10009 2.1.0.9beta1-6
63 * 1.0.9rc1 1 10009 2.1.0.9rc1
64 * 1.0.9beta7-10 1 10009 2.1.0.9beta7-10
65 * 1.0.9rc2 1 10009 2.1.0.9rc2
66 * 1.0.9 1 10009 2.1.0.9
67 * 1.0.10beta1 1 10010 2.1.0.10beta1
68 * 1.0.10rc1 1 10010 2.1.0.10rc1
69 * 1.0.10 1 10010 2.1.0.10
70 * 1.0.11beta1-3 1 10011 2.1.0.11beta1-3
71 * 1.0.11rc1 1 10011 2.1.0.11rc1
72 * 1.0.11 1 10011 2.1.0.11
73 * 1.0.12beta1-2 2 10012 2.1.0.12beta1-2
74 * 1.0.12rc1 2 10012 2.1.0.12rc1
75 * 1.0.12 2 10012 2.1.0.12
76 * 1.1.0a-f - 10100 2.1.1.0a-f (branch abandoned)
77 * 1.2.0beta1-2 2 10200 2.1.2.0beta1-2
78 * 1.2.0beta3-5 3 10200 3.1.2.0beta3-5
79 * 1.2.0rc1 3 10200 3.1.2.0rc1
80 * 1.2.0 3 10200 3.1.2.0
81 * 1.2.1beta1-4 3 10201 3.1.2.1beta1-4
82 * 1.2.1rc1-2 3 10201 3.1.2.1rc1-2
83 * 1.2.1 3 10201 3.1.2.1
84 * 1.2.2beta1-6 12 10202 12.so.0.1.2.2beta1-6
85 * 1.0.13beta1 10 10013 10.so.0.1.0.13beta1
86 * 1.0.13rc1 10 10013 10.so.0.1.0.13rc1
87 * 1.2.2rc1 12 10202 12.so.0.1.2.2rc1
88 * 1.0.13 10 10013 10.so.0.1.0.13
89 * 1.2.2 12 10202 12.so.0.1.2.2
90 * 1.2.3rc1-6 12 10203 12.so.0.1.2.3rc1-6
91 * 1.2.3 12 10203 12.so.0.1.2.3
92 * 1.2.4beta1-3 13 10204 12.so.0.1.2.4beta1-3
93 * 1.0.14rc1 13 10014 10.so.0.1.0.14rc1
94 * 1.2.4rc1 13 10204 12.so.0.1.2.4rc1
95 * 1.0.14 10 10014 10.so.0.1.0.14
96 * 1.2.4 13 10204 12.so.0.1.2.4
97 * 1.2.5beta1-2 13 10205 12.so.0.1.2.5beta1-2
98 * 1.0.15rc1-3 10 10015 10.so.0.1.0.15rc1-3
99 * 1.2.5rc1-3 13 10205 12.so.0.1.2.5rc1-3
100 * 1.0.15 10 10015 10.so.0.1.0.15
101 * 1.2.5 13 10205 12.so.0.1.2.5
102 * 1.2.6beta1-4 13 10206 12.so.0.1.2.6beta1-4
103 * 1.0.16 10 10016 10.so.0.1.0.16
104 * 1.2.6 13 10206 12.so.0.1.2.6
105 * 1.2.7beta1-2 13 10207 12.so.0.1.2.7beta1-2
106 * 1.0.17rc1 10 10017 10.so.0.1.0.17rc1
107 * 1.2.7rc1 13 10207 12.so.0.1.2.7rc1
108 * 1.0.17 10 10017 10.so.0.1.0.17
109 * 1.2.7 13 10207 12.so.0.1.2.7
110 * 1.2.8beta1-5 13 10208 12.so.0.1.2.8beta1-5
111 * 1.0.18rc1-5 10 10018 10.so.0.1.0.18rc1-5
112 * 1.2.8rc1-5 13 10208 12.so.0.1.2.8rc1-5
113 * 1.0.18 10 10018 10.so.0.1.0.18
114 * 1.2.8 13 10208 12.so.0.1.2.8
115 * 1.2.9beta1-3 13 10209 12.so.0.1.2.9beta1-3
116 * 1.2.9beta4-11 13 10209 12.so.0.9[.0]
117 * 1.2.9rc1 13 10209 12.so.0.9[.0]
118 * 1.2.9 13 10209 12.so.0.9[.0]
119 * 1.2.10beta1-8 13 10210 12.so.0.10[.0]
120 * 1.2.10rc1-3 13 10210 12.so.0.10[.0]
121 * 1.2.10 13 10210 12.so.0.10[.0]
122 * 1.2.11beta1-4 13 10211 12.so.0.11[.0]
123 * 1.0.19rc1-5 10 10019 10.so.0.19[.0]
124 * 1.2.11rc1-5 13 10211 12.so.0.11[.0]
125 * 1.0.19 10 10019 10.so.0.19[.0]
126 * 1.2.11 13 10211 12.so.0.11[.0]
127 * 1.0.20 10 10020 10.so.0.20[.0]
128 * 1.2.12 13 10212 12.so.0.12[.0]
129 * 1.2.13beta1 13 10213 12.so.0.13[.0]
130 * 1.0.21 10 10021 10.so.0.21[.0]
131 * 1.2.13 13 10213 12.so.0.13[.0]
132 * 1.2.14beta1-2 13 10214 12.so.0.14[.0]
133 * 1.0.22rc1 10 10022 10.so.0.22[.0]
134 * 1.2.14rc1 13 10214 12.so.0.14[.0]
135 * 1.0.22 10 10022 10.so.0.22[.0]
136 * 1.2.14 13 10214 12.so.0.14[.0]
137 * 1.2.15beta1-6 13 10215 12.so.0.15[.0]
138 * 1.0.23rc1-5 10 10023 10.so.0.23[.0]
139 * 1.2.15rc1-5 13 10215 12.so.0.15[.0]
140 * 1.0.23 10 10023 10.so.0.23[.0]
141 * 1.2.15 13 10215 12.so.0.15[.0]
142 * 1.2.16beta1-2 13 10216 12.so.0.16[.0]
143 * 1.2.16rc1 13 10216 12.so.0.16[.0]
144 * 1.0.24 10 10024 10.so.0.24[.0]
145 * 1.2.16 13 10216 12.so.0.16[.0]
146 * 1.2.17beta1-2 13 10217 12.so.0.17[.0]
147 * 1.0.25rc1 10 10025 10.so.0.25[.0]
148 * 1.2.17rc1-3 13 10217 12.so.0.17[.0]
149 * 1.0.25 10 10025 10.so.0.25[.0]
150 * 1.2.17 13 10217 12.so.0.17[.0]
151 * 1.0.26 10 10026 10.so.0.26[.0]
152 * 1.2.18 13 10218 12.so.0.18[.0]
153 * 1.2.19beta1-31 13 10219 12.so.0.19[.0]
154 * 1.0.27rc1-6 10 10027 10.so.0.27[.0]
155 * 1.2.19rc1-6 13 10219 12.so.0.19[.0]
156 * 1.0.27 10 10027 10.so.0.27[.0]
157 * 1.2.19 13 10219 12.so.0.19[.0]
158 * 1.2.20beta01-04 13 10220 12.so.0.20[.0]
159 * 1.0.28rc1-6 10 10028 10.so.0.28[.0]
160 * 1.2.20rc1-6 13 10220 12.so.0.20[.0]
161 * 1.0.28 10 10028 10.so.0.28[.0]
162 * 1.2.20 13 10220 12.so.0.20[.0]
163 * 1.2.21beta1-2 13 10221 12.so.0.21[.0]
164 * 1.2.21rc1-3 13 10221 12.so.0.21[.0]
165 * 1.0.29 10 10029 10.so.0.29[.0]
166 * 1.2.21 13 10221 12.so.0.21[.0]
167 * 1.2.22beta1-4 13 10222 12.so.0.22[.0]
168 * 1.0.30rc1 10 10030 10.so.0.30[.0]
169 * 1.2.22rc1 13 10222 12.so.0.22[.0]
170 * 1.0.30 10 10030 10.so.0.30[.0]
171 * 1.2.22 13 10222 12.so.0.22[.0]
172 * 1.2.23beta01-05 13 10223 12.so.0.23[.0]
173 * 1.2.23rc01 13 10223 12.so.0.23[.0]
174 * 1.2.23 13 10223 12.so.0.23[.0]
175 * 1.2.24beta01-02 13 10224 12.so.0.24[.0]
176 * 1.2.24rc01 13 10224 12.so.0.24[.0]
177 * 1.2.24 13 10224 12.so.0.24[.0]
178 *
179 * Henceforth the source version will match the shared-library major
180 * and minor numbers; the shared-library major version number will be
181 * used for changes in backward compatibility, as it is intended. The
182 * PNG_LIBPNG_VER macro, which is not used within libpng but is available
183 * for applications, is an unsigned integer of the form xyyzz corresponding
184 * to the source version x.y.z (leading zeros in y and z). Beta versions
185 * were given the previous public release number plus a letter, until
186 * version 1.0.6j; from then on they were given the upcoming public
187 * release number plus "betaNN" or "rcN".
188 *
189 * Binary incompatibility exists only when applications make direct access
190 * to the info_ptr or png_ptr members through png.h, and the compiled
191 * application is loaded with a different version of the library.
192 *
193 * DLLNUM will change each time there are forward or backward changes
194 * in binary compatibility (e.g., when a new feature is added).
195 *
196 * See libpng.txt or libpng.3 for more information. The PNG specification
197 * is available as a W3C Recommendation and as an ISO Specification,
198 * <http://www.w3.org/TR/2003/REC-PNG-20031110/
199 */
200
201/*
202 * COPYRIGHT NOTICE, DISCLAIMER, and LICENSE:
203 *
204 * If you modify libpng you may insert additional notices immediately following
205 * this sentence.
206 *
207 * libpng versions 1.2.6, August 15, 2004, through 1.2.24, December 14, 2007, are
208 * Copyright (c) 2004, 2006-2007 Glenn Randers-Pehrson, and are
209 * distributed according to the same disclaimer and license as libpng-1.2.5
210 * with the following individual added to the list of Contributing Authors:
211 *
212 * Cosmin Truta
213 *
214 * libpng versions 1.0.7, July 1, 2000, through 1.2.5, October 3, 2002, are
215 * Copyright (c) 2000-2002 Glenn Randers-Pehrson, and are
216 * distributed according to the same disclaimer and license as libpng-1.0.6
217 * with the following individuals added to the list of Contributing Authors:
218 *
219 * Simon-Pierre Cadieux
220 * Eric S. Raymond
221 * Gilles Vollant
222 *
223 * and with the following additions to the disclaimer:
224 *
225 * There is no warranty against interference with your enjoyment of the
226 * library or against infringement. There is no warranty that our
227 * efforts or the library will fulfill any of your particular purposes
228 * or needs. This library is provided with all faults, and the entire
229 * risk of satisfactory quality, performance, accuracy, and effort is with
230 * the user.
231 *
232 * libpng versions 0.97, January 1998, through 1.0.6, March 20, 2000, are
233 * Copyright (c) 1998, 1999, 2000 Glenn Randers-Pehrson, and are
234 * distributed according to the same disclaimer and license as libpng-0.96,
235 * with the following individuals added to the list of Contributing Authors:
236 *
237 * Tom Lane
238 * Glenn Randers-Pehrson
239 * Willem van Schaik
240 *
241 * libpng versions 0.89, June 1996, through 0.96, May 1997, are
242 * Copyright (c) 1996, 1997 Andreas Dilger
243 * Distributed according to the same disclaimer and license as libpng-0.88,
244 * with the following individuals added to the list of Contributing Authors:
245 *
246 * John Bowler
247 * Kevin Bracey
248 * Sam Bushell
249 * Magnus Holmgren
250 * Greg Roelofs
251 * Tom Tanner
252 *
253 * libpng versions 0.5, May 1995, through 0.88, January 1996, are
254 * Copyright (c) 1995, 1996 Guy Eric Schalnat, Group 42, Inc.
255 *
256 * For the purposes of this copyright and license, "Contributing Authors"
257 * is defined as the following set of individuals:
258 *
259 * Andreas Dilger
260 * Dave Martindale
261 * Guy Eric Schalnat
262 * Paul Schmidt
263 * Tim Wegner
264 *
265 * The PNG Reference Library is supplied "AS IS". The Contributing Authors
266 * and Group 42, Inc. disclaim all warranties, expressed or implied,
267 * including, without limitation, the warranties of merchantability and of
268 * fitness for any purpose. The Contributing Authors and Group 42, Inc.
269 * assume no liability for direct, indirect, incidental, special, exemplary,
270 * or consequential damages, which may result from the use of the PNG
271 * Reference Library, even if advised of the possibility of such damage.
272 *
273 * Permission is hereby granted to use, copy, modify, and distribute this
274 * source code, or portions hereof, for any purpose, without fee, subject
275 * to the following restrictions:
276 *
277 * 1. The origin of this source code must not be misrepresented.
278 *
279 * 2. Altered versions must be plainly marked as such and
280 * must not be misrepresented as being the original source.
281 *
282 * 3. This Copyright notice may not be removed or altered from
283 * any source or altered source distribution.
284 *
285 * The Contributing Authors and Group 42, Inc. specifically permit, without
286 * fee, and encourage the use of this source code as a component to
287 * supporting the PNG file format in commercial products. If you use this
288 * source code in a product, acknowledgment is not required but would be
289 * appreciated.
290 */
291
292/*
293 * A "png_get_copyright" function is available, for convenient use in "about"
294 * boxes and the like:
295 *
296 * printf("%s",png_get_copyright(NULL));
297 *
298 * Also, the PNG logo (in PNG format, of course) is supplied in the
299 * files "pngbar.png" and "pngbar.jpg (88x31) and "pngnow.png" (98x31).
300 */
301
302/*
303 * Libpng is OSI Certified Open Source Software. OSI Certified is a
304 * certification mark of the Open Source Initiative.
305 */
306
307/*
308 * The contributing authors would like to thank all those who helped
309 * with testing, bug fixes, and patience. This wouldn't have been
310 * possible without all of you.
311 *
312 * Thanks to Frank J. T. Wojcik for helping with the documentation.
313 */
314
315/*
316 * Y2K compliance in libpng:
317 * =========================
318 *
319 * December 14, 2007
320 *
321 * Since the PNG Development group is an ad-hoc body, we can't make
322 * an official declaration.
323 *
324 * This is your unofficial assurance that libpng from version 0.71 and
325 * upward through 1.2.24 are Y2K compliant. It is my belief that earlier
326 * versions were also Y2K compliant.
327 *
328 * Libpng only has three year fields. One is a 2-byte unsigned integer
329 * that will hold years up to 65535. The other two hold the date in text
330 * format, and will hold years up to 9999.
331 *
332 * The integer is
333 * "png_uint_16 year" in png_time_struct.
334 *
335 * The strings are
336 * "png_charp time_buffer" in png_struct and
337 * "near_time_buffer", which is a local character string in png.c.
338 *
339 * There are seven time-related functions:
340 * png.c: png_convert_to_rfc_1123() in png.c
341 * (formerly png_convert_to_rfc_1152() in error)
342 * png_convert_from_struct_tm() in pngwrite.c, called in pngwrite.c
343 * png_convert_from_time_t() in pngwrite.c
344 * png_get_tIME() in pngget.c
345 * png_handle_tIME() in pngrutil.c, called in pngread.c
346 * png_set_tIME() in pngset.c
347 * png_write_tIME() in pngwutil.c, called in pngwrite.c
348 *
349 * All handle dates properly in a Y2K environment. The
350 * png_convert_from_time_t() function calls gmtime() to convert from system
351 * clock time, which returns (year - 1900), which we properly convert to
352 * the full 4-digit year. There is a possibility that applications using
353 * libpng are not passing 4-digit years into the png_convert_to_rfc_1123()
354 * function, or that they are incorrectly passing only a 2-digit year
355 * instead of "year - 1900" into the png_convert_from_struct_tm() function,
356 * but this is not under our control. The libpng documentation has always
357 * stated that it works with 4-digit years, and the APIs have been
358 * documented as such.
359 *
360 * The tIME chunk itself is also Y2K compliant. It uses a 2-byte unsigned
361 * integer to hold the year, and can hold years as large as 65535.
362 *
363 * zlib, upon which libpng depends, is also Y2K compliant. It contains
364 * no date-related code.
365 *
366 * Glenn Randers-Pehrson
367 * libpng maintainer
368 * PNG Development Group
369 */
370
371#ifndef PNG_H
372#define PNG_H
373
374/* This is not the place to learn how to use libpng. The file libpng.txt
375 * describes how to use libpng, and the file example.c summarizes it
376 * with some code on which to build. This file is useful for looking
377 * at the actual function definitions and structure components.
378 */
379
380/* Version information for png.h - this should match the version in png.c */
381#define PNG_LIBPNG_VER_STRING "1.2.24"
382#define PNG_HEADER_VERSION_STRING \
383 " libpng version 1.2.24 - December 14, 2007\n"
384
385#define PNG_LIBPNG_VER_SONUM 0
386#define PNG_LIBPNG_VER_DLLNUM 13
387
388/* These should match the first 3 components of PNG_LIBPNG_VER_STRING: */
389#define PNG_LIBPNG_VER_MAJOR 1
390#define PNG_LIBPNG_VER_MINOR 2
391#define PNG_LIBPNG_VER_RELEASE 24
392/* This should match the numeric part of the final component of
393 * PNG_LIBPNG_VER_STRING, omitting any leading zero: */
394
395#define PNG_LIBPNG_VER_BUILD 0
396
397/* Release Status */
398#define PNG_LIBPNG_BUILD_ALPHA 1
399#define PNG_LIBPNG_BUILD_BETA 2
400#define PNG_LIBPNG_BUILD_RC 3
401#define PNG_LIBPNG_BUILD_STABLE 4
402#define PNG_LIBPNG_BUILD_RELEASE_STATUS_MASK 7
403
404/* Release-Specific Flags */
405#define PNG_LIBPNG_BUILD_PATCH 8 /* Can be OR'ed with
406 PNG_LIBPNG_BUILD_STABLE only */
407#define PNG_LIBPNG_BUILD_PRIVATE 16 /* Cannot be OR'ed with
408 PNG_LIBPNG_BUILD_SPECIAL */
409#define PNG_LIBPNG_BUILD_SPECIAL 32 /* Cannot be OR'ed with
410 PNG_LIBPNG_BUILD_PRIVATE */
411
412#define PNG_LIBPNG_BUILD_BASE_TYPE PNG_LIBPNG_BUILD_STABLE
413
414/* Careful here. At one time, Guy wanted to use 082, but that would be octal.
415 * We must not include leading zeros.
416 * Versions 0.7 through 1.0.0 were in the range 0 to 100 here (only
417 * version 1.0.0 was mis-numbered 100 instead of 10000). From
418 * version 1.0.1 it's xxyyzz, where x=major, y=minor, z=release */
419#define PNG_LIBPNG_VER 10224 /* 1.2.24 */
420
421#ifndef PNG_VERSION_INFO_ONLY
422/* include the compression library's header */
423//#include "zlib.h"
424#include "../ZLIB/zlib.h"
425#endif
426
427/* include all user configurable info, including optional assembler routines */
428#include "pngconf.h"
429
430/*
431 * Added at libpng-1.2.8 */
432/* Ref MSDN: Private as priority over Special
433 * VS_FF_PRIVATEBUILD File *was not* built using standard release
434 * procedures. If this value is given, the StringFileInfo block must
435 * contain a PrivateBuild string.
436 *
437 * VS_FF_SPECIALBUILD File *was* built by the original company using
438 * standard release procedures but is a variation of the standard
439 * file of the same version number. If this value is given, the
440 * StringFileInfo block must contain a SpecialBuild string.
441 */
442
443#if defined(PNG_USER_PRIVATEBUILD)
444# define PNG_LIBPNG_BUILD_TYPE \
445 (PNG_LIBPNG_BUILD_BASE_TYPE | PNG_LIBPNG_BUILD_PRIVATE)
446#else
447# if defined(PNG_LIBPNG_SPECIALBUILD)
448# define PNG_LIBPNG_BUILD_TYPE \
449 (PNG_LIBPNG_BUILD_BASE_TYPE | PNG_LIBPNG_BUILD_SPECIAL)
450# else
451# define PNG_LIBPNG_BUILD_TYPE (PNG_LIBPNG_BUILD_BASE_TYPE)
452# endif
453#endif
454
455#ifndef PNG_VERSION_INFO_ONLY
456
457/* Inhibit C++ name-mangling for libpng functions but not for system calls. */
458#ifdef __cplusplus
459extern "C" {
460#endif /* __cplusplus */
461
462/* This file is arranged in several sections. The first section contains
463 * structure and type definitions. The second section contains the external
464 * library functions, while the third has the internal library functions,
465 * which applications aren't expected to use directly.
466 */
467
468#ifndef PNG_NO_TYPECAST_NULL
469#define int_p_NULL (int *)NULL
470#define png_bytep_NULL (png_bytep)NULL
471#define png_bytepp_NULL (png_bytepp)NULL
472#define png_doublep_NULL (png_doublep)NULL
473#define png_error_ptr_NULL (png_error_ptr)NULL
474#define png_flush_ptr_NULL (png_flush_ptr)NULL
475#define png_free_ptr_NULL (png_free_ptr)NULL
476#define png_infopp_NULL (png_infopp)NULL
477#define png_malloc_ptr_NULL (png_malloc_ptr)NULL
478#define png_read_status_ptr_NULL (png_read_status_ptr)NULL
479#define png_rw_ptr_NULL (png_rw_ptr)NULL
480#define png_structp_NULL (png_structp)NULL
481#define png_uint_16p_NULL (png_uint_16p)NULL
482#define png_voidp_NULL (png_voidp)NULL
483#define png_write_status_ptr_NULL (png_write_status_ptr)NULL
484#else
485#define int_p_NULL NULL
486#define png_bytep_NULL NULL
487#define png_bytepp_NULL NULL
488#define png_doublep_NULL NULL
489#define png_error_ptr_NULL NULL
490#define png_flush_ptr_NULL NULL
491#define png_free_ptr_NULL NULL
492#define png_infopp_NULL NULL
493#define png_malloc_ptr_NULL NULL
494#define png_read_status_ptr_NULL NULL
495#define png_rw_ptr_NULL NULL
496#define png_structp_NULL NULL
497#define png_uint_16p_NULL NULL
498#define png_voidp_NULL NULL
499#define png_write_status_ptr_NULL NULL
500#endif
501
502/* variables declared in png.c - only it needs to define PNG_NO_EXTERN */
503#if !defined(PNG_NO_EXTERN) || defined(PNG_ALWAYS_EXTERN)
504/* Version information for C files, stored in png.c. This had better match
505 * the version above.
506 */
507#ifdef PNG_USE_GLOBAL_ARRAYS
508PNG_EXPORT_VAR (PNG_CONST char) png_libpng_ver[18];
509 /* need room for 99.99.99beta99z */
510#else
511#define png_libpng_ver png_get_header_ver(NULL)
512#endif
513
514#ifdef PNG_USE_GLOBAL_ARRAYS
515/* This was removed in version 1.0.5c */
516/* Structures to facilitate easy interlacing. See png.c for more details */
517PNG_EXPORT_VAR (PNG_CONST int FARDATA) png_pass_start[7];
518PNG_EXPORT_VAR (PNG_CONST int FARDATA) png_pass_inc[7];
519PNG_EXPORT_VAR (PNG_CONST int FARDATA) png_pass_ystart[7];
520PNG_EXPORT_VAR (PNG_CONST int FARDATA) png_pass_yinc[7];
521PNG_EXPORT_VAR (PNG_CONST int FARDATA) png_pass_mask[7];
522PNG_EXPORT_VAR (PNG_CONST int FARDATA) png_pass_dsp_mask[7];
523/* This isn't currently used. If you need it, see png.c for more details.
524PNG_EXPORT_VAR (PNG_CONST int FARDATA) png_pass_height[7];
525*/
526#endif
527
528#endif /* PNG_NO_EXTERN */
529
530/* Three color definitions. The order of the red, green, and blue, (and the
531 * exact size) is not important, although the size of the fields need to
532 * be png_byte or png_uint_16 (as defined below).
533 */
534typedef struct png_color_struct
535{
536 png_byte red;
537 png_byte green;
538 png_byte blue;
539} png_color;
540typedef png_color FAR * png_colorp;
541typedef png_color FAR * FAR * png_colorpp;
542
543typedef struct png_color_16_struct
544{
545 png_byte index; /* used for palette files */
546 png_uint_16 red; /* for use in red green blue files */
547 png_uint_16 green;
548 png_uint_16 blue;
549 png_uint_16 gray; /* for use in grayscale files */
550} png_color_16;
551typedef png_color_16 FAR * png_color_16p;
552typedef png_color_16 FAR * FAR * png_color_16pp;
553
554typedef struct png_color_8_struct
555{
556 png_byte red; /* for use in red green blue files */
557 png_byte green;
558 png_byte blue;
559 png_byte gray; /* for use in grayscale files */
560 png_byte alpha; /* for alpha channel files */
561} png_color_8;
562typedef png_color_8 FAR * png_color_8p;
563typedef png_color_8 FAR * FAR * png_color_8pp;
564
565/*
566 * The following two structures are used for the in-core representation
567 * of sPLT chunks.
568 */
569typedef struct png_sPLT_entry_struct
570{
571 png_uint_16 red;
572 png_uint_16 green;
573 png_uint_16 blue;
574 png_uint_16 alpha;
575 png_uint_16 frequency;
576} png_sPLT_entry;
577typedef png_sPLT_entry FAR * png_sPLT_entryp;
578typedef png_sPLT_entry FAR * FAR * png_sPLT_entrypp;
579
580/* When the depth of the sPLT palette is 8 bits, the color and alpha samples
581 * occupy the LSB of their respective members, and the MSB of each member
582 * is zero-filled. The frequency member always occupies the full 16 bits.
583 */
584
585typedef struct png_sPLT_struct
586{
587 png_charp name; /* palette name */
588 png_byte depth; /* depth of palette samples */
589 png_sPLT_entryp entries; /* palette entries */
590 png_int_32 nentries; /* number of palette entries */
591} png_sPLT_t;
592typedef png_sPLT_t FAR * png_sPLT_tp;
593typedef png_sPLT_t FAR * FAR * png_sPLT_tpp;
594
595#ifdef PNG_TEXT_SUPPORTED
596/* png_text holds the contents of a text/ztxt/itxt chunk in a PNG file,
597 * and whether that contents is compressed or not. The "key" field
598 * points to a regular zero-terminated C string. The "text", "lang", and
599 * "lang_key" fields can be regular C strings, empty strings, or NULL pointers.
600 * However, the * structure returned by png_get_text() will always contain
601 * regular zero-terminated C strings (possibly empty), never NULL pointers,
602 * so they can be safely used in printf() and other string-handling functions.
603 */
604typedef struct png_text_struct
605{
606 int compression; /* compression value:
607 -1: tEXt, none
608 0: zTXt, deflate
609 1: iTXt, none
610 2: iTXt, deflate */
611 png_charp key; /* keyword, 1-79 character description of "text" */
612 png_charp text; /* comment, may be an empty string (ie "")
613 or a NULL pointer */
614 png_size_t text_length; /* length of the text string */
615#ifdef PNG_iTXt_SUPPORTED
616 png_size_t itxt_length; /* length of the itxt string */
617 png_charp lang; /* language code, 0-79 characters
618 or a NULL pointer */
619 png_charp lang_key; /* keyword translated UTF-8 string, 0 or more
620 chars or a NULL pointer */
621#endif
622} png_text;
623typedef png_text FAR * png_textp;
624typedef png_text FAR * FAR * png_textpp;
625#endif
626
627/* Supported compression types for text in PNG files (tEXt, and zTXt).
628 * The values of the PNG_TEXT_COMPRESSION_ defines should NOT be changed. */
629#define PNG_TEXT_COMPRESSION_NONE_WR -3
630#define PNG_TEXT_COMPRESSION_zTXt_WR -2
631#define PNG_TEXT_COMPRESSION_NONE -1
632#define PNG_TEXT_COMPRESSION_zTXt 0
633#define PNG_ITXT_COMPRESSION_NONE 1
634#define PNG_ITXT_COMPRESSION_zTXt 2
635#define PNG_TEXT_COMPRESSION_LAST 3 /* Not a valid value */
636
637/* png_time is a way to hold the time in an machine independent way.
638 * Two conversions are provided, both from time_t and struct tm. There
639 * is no portable way to convert to either of these structures, as far
640 * as I know. If you know of a portable way, send it to me. As a side
641 * note - PNG has always been Year 2000 compliant!
642 */
643typedef struct png_time_struct
644{
645 png_uint_16 year; /* full year, as in, 1995 */
646 png_byte month; /* month of year, 1 - 12 */
647 png_byte day; /* day of month, 1 - 31 */
648 png_byte hour; /* hour of day, 0 - 23 */
649 png_byte minute; /* minute of hour, 0 - 59 */
650 png_byte second; /* second of minute, 0 - 60 (for leap seconds) */
651} png_time;
652typedef png_time FAR * png_timep;
653typedef png_time FAR * FAR * png_timepp;
654
655#if defined(PNG_UNKNOWN_CHUNKS_SUPPORTED)
656/* png_unknown_chunk is a structure to hold queued chunks for which there is
657 * no specific support. The idea is that we can use this to queue
658 * up private chunks for output even though the library doesn't actually
659 * know about their semantics.
660 */
661#define PNG_CHUNK_NAME_LENGTH 5
662typedef struct png_unknown_chunk_t
663{
664 png_byte name[PNG_CHUNK_NAME_LENGTH];
665 png_byte *data;
666 png_size_t size;
667
668 /* libpng-using applications should NOT directly modify this byte. */
669 png_byte location; /* mode of operation at read time */
670}
671png_unknown_chunk;
672typedef png_unknown_chunk FAR * png_unknown_chunkp;
673typedef png_unknown_chunk FAR * FAR * png_unknown_chunkpp;
674#endif
675
676/* png_info is a structure that holds the information in a PNG file so
677 * that the application can find out the characteristics of the image.
678 * If you are reading the file, this structure will tell you what is
679 * in the PNG file. If you are writing the file, fill in the information
680 * you want to put into the PNG file, then call png_write_info().
681 * The names chosen should be very close to the PNG specification, so
682 * consult that document for information about the meaning of each field.
683 *
684 * With libpng < 0.95, it was only possible to directly set and read the
685 * the values in the png_info_struct, which meant that the contents and
686 * order of the values had to remain fixed. With libpng 0.95 and later,
687 * however, there are now functions that abstract the contents of
688 * png_info_struct from the application, so this makes it easier to use
689 * libpng with dynamic libraries, and even makes it possible to use
690 * libraries that don't have all of the libpng ancillary chunk-handing
691 * functionality.
692 *
693 * In any case, the order of the parameters in png_info_struct should NOT
694 * be changed for as long as possible to keep compatibility with applications
695 * that use the old direct-access method with png_info_struct.
696 *
697 * The following members may have allocated storage attached that should be
698 * cleaned up before the structure is discarded: palette, trans, text,
699 * pcal_purpose, pcal_units, pcal_params, hist, iccp_name, iccp_profile,
700 * splt_palettes, scal_unit, row_pointers, and unknowns. By default, these
701 * are automatically freed when the info structure is deallocated, if they were
702 * allocated internally by libpng. This behavior can be changed by means
703 * of the png_data_freer() function.
704 *
705 * More allocation details: all the chunk-reading functions that
706 * change these members go through the corresponding png_set_*
707 * functions. A function to clear these members is available: see
708 * png_free_data(). The png_set_* functions do not depend on being
709 * able to point info structure members to any of the storage they are
710 * passed (they make their own copies), EXCEPT that the png_set_text
711 * functions use the same storage passed to them in the text_ptr or
712 * itxt_ptr structure argument, and the png_set_rows and png_set_unknowns
713 * functions do not make their own copies.
714 */
715typedef struct png_info_struct
716{
717 /* the following are necessary for every PNG file */
718 png_uint_32 width; /* width of image in pixels (from IHDR) */
719 png_uint_32 height; /* height of image in pixels (from IHDR) */
720 png_uint_32 valid; /* valid chunk data (see PNG_INFO_ below) */
721 png_uint_32 rowbytes; /* bytes needed to hold an untransformed row */
722 png_colorp palette; /* array of color values (valid & PNG_INFO_PLTE) */
723 png_uint_16 num_palette; /* number of color entries in "palette" (PLTE) */
724 png_uint_16 num_trans; /* number of transparent palette color (tRNS) */
725 png_byte bit_depth; /* 1, 2, 4, 8, or 16 bits/channel (from IHDR) */
726 png_byte color_type; /* see PNG_COLOR_TYPE_ below (from IHDR) */
727 /* The following three should have been named *_method not *_type */
728 png_byte compression_type; /* must be PNG_COMPRESSION_TYPE_BASE (IHDR) */
729 png_byte filter_type; /* must be PNG_FILTER_TYPE_BASE (from IHDR) */
730 png_byte interlace_type; /* One of PNG_INTERLACE_NONE, PNG_INTERLACE_ADAM7 */
731
732 /* The following is informational only on read, and not used on writes. */
733 png_byte channels; /* number of data channels per pixel (1, 2, 3, 4) */
734 png_byte pixel_depth; /* number of bits per pixel */
735 png_byte spare_byte; /* to align the data, and for future use */
736 png_byte signature[8]; /* magic bytes read by libpng from start of file */
737
738 /* The rest of the data is optional. If you are reading, check the
739 * valid field to see if the information in these are valid. If you
740 * are writing, set the valid field to those chunks you want written,
741 * and initialize the appropriate fields below.
742 */
743
744#if defined(PNG_gAMA_SUPPORTED) && defined(PNG_FLOATING_POINT_SUPPORTED)
745 /* The gAMA chunk describes the gamma characteristics of the system
746 * on which the image was created, normally in the range [1.0, 2.5].
747 * Data is valid if (valid & PNG_INFO_gAMA) is non-zero.
748 */
749 float gamma; /* gamma value of image, if (valid & PNG_INFO_gAMA) */
750#endif
751
752#if defined(PNG_sRGB_SUPPORTED)
753 /* GR-P, 0.96a */
754 /* Data valid if (valid & PNG_INFO_sRGB) non-zero. */
755 png_byte srgb_intent; /* sRGB rendering intent [0, 1, 2, or 3] */
756#endif
757
758#if defined(PNG_TEXT_SUPPORTED)
759 /* The tEXt, and zTXt chunks contain human-readable textual data in
760 * uncompressed, compressed, and optionally compressed forms, respectively.
761 * The data in "text" is an array of pointers to uncompressed,
762 * null-terminated C strings. Each chunk has a keyword that describes the
763 * textual data contained in that chunk. Keywords are not required to be
764 * unique, and the text string may be empty. Any number of text chunks may
765 * be in an image.
766 */
767 int num_text; /* number of comments read/to write */
768 int max_text; /* current size of text array */
769 png_textp text; /* array of comments read/to write */
770#endif /* PNG_TEXT_SUPPORTED */
771
772#if defined(PNG_tIME_SUPPORTED)
773 /* The tIME chunk holds the last time the displayed image data was
774 * modified. See the png_time struct for the contents of this struct.
775 */
776 png_time mod_time;
777#endif
778
779#if defined(PNG_sBIT_SUPPORTED)
780 /* The sBIT chunk specifies the number of significant high-order bits
781 * in the pixel data. Values are in the range [1, bit_depth], and are
782 * only specified for the channels in the pixel data. The contents of
783 * the low-order bits is not specified. Data is valid if
784 * (valid & PNG_INFO_sBIT) is non-zero.
785 */
786 png_color_8 sig_bit; /* significant bits in color channels */
787#endif
788
789#if defined(PNG_tRNS_SUPPORTED) || defined(PNG_READ_EXPAND_SUPPORTED) || \
790defined(PNG_READ_BACKGROUND_SUPPORTED)
791 /* The tRNS chunk supplies transparency data for paletted images and
792 * other image types that don't need a full alpha channel. There are
793 * "num_trans" transparency values for a paletted image, stored in the
794 * same order as the palette colors, starting from index 0. Values
795 * for the data are in the range [0, 255], ranging from fully transparent
796 * to fully opaque, respectively. For non-paletted images, there is a
797 * single color specified that should be treated as fully transparent.
798 * Data is valid if (valid & PNG_INFO_tRNS) is non-zero.
799 */
800 png_bytep trans; /* transparent values for paletted image */
801 png_color_16 trans_values; /* transparent color for non-palette image */
802#endif
803
804#if defined(PNG_bKGD_SUPPORTED) || defined(PNG_READ_BACKGROUND_SUPPORTED)
805 /* The bKGD chunk gives the suggested image background color if the
806 * display program does not have its own background color and the image
807 * is needs to composited onto a background before display. The colors
808 * in "background" are normally in the same color space/depth as the
809 * pixel data. Data is valid if (valid & PNG_INFO_bKGD) is non-zero.
810 */
811 png_color_16 background;
812#endif
813
814#if defined(PNG_oFFs_SUPPORTED)
815 /* The oFFs chunk gives the offset in "offset_unit_type" units rightwards
816 * and downwards from the top-left corner of the display, page, or other
817 * application-specific co-ordinate space. See the PNG_OFFSET_ defines
818 * below for the unit types. Valid if (valid & PNG_INFO_oFFs) non-zero.
819 */
820 png_int_32 x_offset; /* x offset on page */
821 png_int_32 y_offset; /* y offset on page */
822 png_byte offset_unit_type; /* offset units type */
823#endif
824
825#if defined(PNG_pHYs_SUPPORTED)
826 /* The pHYs chunk gives the physical pixel density of the image for
827 * display or printing in "phys_unit_type" units (see PNG_RESOLUTION_
828 * defines below). Data is valid if (valid & PNG_INFO_pHYs) is non-zero.
829 */
830 png_uint_32 x_pixels_per_unit; /* horizontal pixel density */
831 png_uint_32 y_pixels_per_unit; /* vertical pixel density */
832 png_byte phys_unit_type; /* resolution type (see PNG_RESOLUTION_ below) */
833#endif
834
835#if defined(PNG_hIST_SUPPORTED)
836 /* The hIST chunk contains the relative frequency or importance of the
837 * various palette entries, so that a viewer can intelligently select a
838 * reduced-color palette, if required. Data is an array of "num_palette"
839 * values in the range [0,65535]. Data valid if (valid & PNG_INFO_hIST)
840 * is non-zero.
841 */
842 png_uint_16p hist;
843#endif
844
845#ifdef PNG_cHRM_SUPPORTED
846 /* The cHRM chunk describes the CIE color characteristics of the monitor
847 * on which the PNG was created. This data allows the viewer to do gamut
848 * mapping of the input image to ensure that the viewer sees the same
849 * colors in the image as the creator. Values are in the range
850 * [0.0, 0.8]. Data valid if (valid & PNG_INFO_cHRM) non-zero.
851 */
852#ifdef PNG_FLOATING_POINT_SUPPORTED
853 float x_white;
854 float y_white;
855 float x_red;
856 float y_red;
857 float x_green;
858 float y_green;
859 float x_blue;
860 float y_blue;
861#endif
862#endif
863
864#if defined(PNG_pCAL_SUPPORTED)
865 /* The pCAL chunk describes a transformation between the stored pixel
866 * values and original physical data values used to create the image.
867 * The integer range [0, 2^bit_depth - 1] maps to the floating-point
868 * range given by [pcal_X0, pcal_X1], and are further transformed by a
869 * (possibly non-linear) transformation function given by "pcal_type"
870 * and "pcal_params" into "pcal_units". Please see the PNG_EQUATION_
871 * defines below, and the PNG-Group's PNG extensions document for a
872 * complete description of the transformations and how they should be
873 * implemented, and for a description of the ASCII parameter strings.
874 * Data values are valid if (valid & PNG_INFO_pCAL) non-zero.
875 */
876 png_charp pcal_purpose; /* pCAL chunk description string */
877 png_int_32 pcal_X0; /* minimum value */
878 png_int_32 pcal_X1; /* maximum value */
879 png_charp pcal_units; /* Latin-1 string giving physical units */
880 png_charpp pcal_params; /* ASCII strings containing parameter values */
881 png_byte pcal_type; /* equation type (see PNG_EQUATION_ below) */
882 png_byte pcal_nparams; /* number of parameters given in pcal_params */
883#endif
884
885/* New members added in libpng-1.0.6 */
886#ifdef PNG_FREE_ME_SUPPORTED
887 png_uint_32 free_me; /* flags items libpng is responsible for freeing */
888#endif
889
890#if defined(PNG_UNKNOWN_CHUNKS_SUPPORTED)
891 /* storage for unknown chunks that the library doesn't recognize. */
892 png_unknown_chunkp unknown_chunks;
893 png_size_t unknown_chunks_num;
894#endif
895
896#if defined(PNG_iCCP_SUPPORTED)
897 /* iCCP chunk data. */
898 png_charp iccp_name; /* profile name */
899 png_charp iccp_profile; /* International Color Consortium profile data */
900 /* Note to maintainer: should be png_bytep */
901 png_uint_32 iccp_proflen; /* ICC profile data length */
902 png_byte iccp_compression; /* Always zero */
903#endif
904
905#if defined(PNG_sPLT_SUPPORTED)
906 /* data on sPLT chunks (there may be more than one). */
907 png_sPLT_tp splt_palettes;
908 png_uint_32 splt_palettes_num;
909#endif
910
911#if defined(PNG_sCAL_SUPPORTED)
912 /* The sCAL chunk describes the actual physical dimensions of the
913 * subject matter of the graphic. The chunk contains a unit specification
914 * a byte value, and two ASCII strings representing floating-point
915 * values. The values are width and height corresponsing to one pixel
916 * in the image. This external representation is converted to double
917 * here. Data values are valid if (valid & PNG_INFO_sCAL) is non-zero.
918 */
919 png_byte scal_unit; /* unit of physical scale */
920#ifdef PNG_FLOATING_POINT_SUPPORTED
921 double scal_pixel_width; /* width of one pixel */
922 double scal_pixel_height; /* height of one pixel */
923#endif
924#ifdef PNG_FIXED_POINT_SUPPORTED
925 png_charp scal_s_width; /* string containing height */
926 png_charp scal_s_height; /* string containing width */
927#endif
928#endif
929
930#if defined(PNG_INFO_IMAGE_SUPPORTED)
931 /* Memory has been allocated if (valid & PNG_ALLOCATED_INFO_ROWS) non-zero */
932 /* Data valid if (valid & PNG_INFO_IDAT) non-zero */
933 png_bytepp row_pointers; /* the image bits */
934#endif
935
936#if defined(PNG_FIXED_POINT_SUPPORTED) && defined(PNG_gAMA_SUPPORTED)
937 png_fixed_point int_gamma; /* gamma of image, if (valid & PNG_INFO_gAMA) */
938#endif
939
940#if defined(PNG_cHRM_SUPPORTED) && defined(PNG_FIXED_POINT_SUPPORTED)
941 png_fixed_point int_x_white;
942 png_fixed_point int_y_white;
943 png_fixed_point int_x_red;
944 png_fixed_point int_y_red;
945 png_fixed_point int_x_green;
946 png_fixed_point int_y_green;
947 png_fixed_point int_x_blue;
948 png_fixed_point int_y_blue;
949#endif
950
951} png_info;
952
953typedef png_info FAR * png_infop;
954typedef png_info FAR * FAR * png_infopp;
955
956/* Maximum positive integer used in PNG is (2^31)-1 */
957#define PNG_UINT_31_MAX ((png_uint_32)0x7fffffffL)
958#define PNG_UINT_32_MAX ((png_uint_32)(-1))
959#define PNG_SIZE_MAX ((png_size_t)(-1))
960#if defined(PNG_1_0_X) || defined (PNG_1_2_X)
961/* PNG_MAX_UINT is deprecated; use PNG_UINT_31_MAX instead. */
962#define PNG_MAX_UINT PNG_UINT_31_MAX
963#endif
964
965/* These describe the color_type field in png_info. */
966/* color type masks */
967#define PNG_COLOR_MASK_PALETTE 1
968#define PNG_COLOR_MASK_COLOR 2
969#define PNG_COLOR_MASK_ALPHA 4
970
971/* color types. Note that not all combinations are legal */
972#define PNG_COLOR_TYPE_GRAY 0
973#define PNG_COLOR_TYPE_PALETTE (PNG_COLOR_MASK_COLOR | PNG_COLOR_MASK_PALETTE)
974#define PNG_COLOR_TYPE_RGB (PNG_COLOR_MASK_COLOR)
975#define PNG_COLOR_TYPE_RGB_ALPHA (PNG_COLOR_MASK_COLOR | PNG_COLOR_MASK_ALPHA)
976#define PNG_COLOR_TYPE_GRAY_ALPHA (PNG_COLOR_MASK_ALPHA)
977/* aliases */
978#define PNG_COLOR_TYPE_RGBA PNG_COLOR_TYPE_RGB_ALPHA
979#define PNG_COLOR_TYPE_GA PNG_COLOR_TYPE_GRAY_ALPHA
980
981/* This is for compression type. PNG 1.0-1.2 only define the single type. */
982#define PNG_COMPRESSION_TYPE_BASE 0 /* Deflate method 8, 32K window */
983#define PNG_COMPRESSION_TYPE_DEFAULT PNG_COMPRESSION_TYPE_BASE
984
985/* This is for filter type. PNG 1.0-1.2 only define the single type. */
986#define PNG_FILTER_TYPE_BASE 0 /* Single row per-byte filtering */
987#define PNG_INTRAPIXEL_DIFFERENCING 64 /* Used only in MNG datastreams */
988#define PNG_FILTER_TYPE_DEFAULT PNG_FILTER_TYPE_BASE
989
990/* These are for the interlacing type. These values should NOT be changed. */
991#define PNG_INTERLACE_NONE 0 /* Non-interlaced image */
992#define PNG_INTERLACE_ADAM7 1 /* Adam7 interlacing */
993#define PNG_INTERLACE_LAST 2 /* Not a valid value */
994
995/* These are for the oFFs chunk. These values should NOT be changed. */
996#define PNG_OFFSET_PIXEL 0 /* Offset in pixels */
997#define PNG_OFFSET_MICROMETER 1 /* Offset in micrometers (1/10^6 meter) */
998#define PNG_OFFSET_LAST 2 /* Not a valid value */
999
1000/* These are for the pCAL chunk. These values should NOT be changed. */
1001#define PNG_EQUATION_LINEAR 0 /* Linear transformation */
1002#define PNG_EQUATION_BASE_E 1 /* Exponential base e transform */
1003#define PNG_EQUATION_ARBITRARY 2 /* Arbitrary base exponential transform */
1004#define PNG_EQUATION_HYPERBOLIC 3 /* Hyperbolic sine transformation */
1005#define PNG_EQUATION_LAST 4 /* Not a valid value */
1006
1007/* These are for the sCAL chunk. These values should NOT be changed. */
1008#define PNG_SCALE_UNKNOWN 0 /* unknown unit (image scale) */
1009#define PNG_SCALE_METER 1 /* meters per pixel */
1010#define PNG_SCALE_RADIAN 2 /* radians per pixel */
1011#define PNG_SCALE_LAST 3 /* Not a valid value */
1012
1013/* These are for the pHYs chunk. These values should NOT be changed. */
1014#define PNG_RESOLUTION_UNKNOWN 0 /* pixels/unknown unit (aspect ratio) */
1015#define PNG_RESOLUTION_METER 1 /* pixels/meter */
1016#define PNG_RESOLUTION_LAST 2 /* Not a valid value */
1017
1018/* These are for the sRGB chunk. These values should NOT be changed. */
1019#define PNG_sRGB_INTENT_PERCEPTUAL 0
1020#define PNG_sRGB_INTENT_RELATIVE 1
1021#define PNG_sRGB_INTENT_SATURATION 2
1022#define PNG_sRGB_INTENT_ABSOLUTE 3
1023#define PNG_sRGB_INTENT_LAST 4 /* Not a valid value */
1024
1025/* This is for text chunks */
1026#define PNG_KEYWORD_MAX_LENGTH 79
1027
1028/* Maximum number of entries in PLTE/sPLT/tRNS arrays */
1029#define PNG_MAX_PALETTE_LENGTH 256
1030
1031/* These determine if an ancillary chunk's data has been successfully read
1032 * from the PNG header, or if the application has filled in the corresponding
1033 * data in the info_struct to be written into the output file. The values
1034 * of the PNG_INFO_<chunk> defines should NOT be changed.
1035 */
1036#define PNG_INFO_gAMA 0x0001
1037#define PNG_INFO_sBIT 0x0002
1038#define PNG_INFO_cHRM 0x0004
1039#define PNG_INFO_PLTE 0x0008
1040#define PNG_INFO_tRNS 0x0010
1041#define PNG_INFO_bKGD 0x0020
1042#define PNG_INFO_hIST 0x0040
1043#define PNG_INFO_pHYs 0x0080
1044#define PNG_INFO_oFFs 0x0100
1045#define PNG_INFO_tIME 0x0200
1046#define PNG_INFO_pCAL 0x0400
1047#define PNG_INFO_sRGB 0x0800 /* GR-P, 0.96a */
1048#define PNG_INFO_iCCP 0x1000 /* ESR, 1.0.6 */
1049#define PNG_INFO_sPLT 0x2000 /* ESR, 1.0.6 */
1050#define PNG_INFO_sCAL 0x4000 /* ESR, 1.0.6 */
1051#define PNG_INFO_IDAT 0x8000L /* ESR, 1.0.6 */
1052
1053/* This is used for the transformation routines, as some of them
1054 * change these values for the row. It also should enable using
1055 * the routines for other purposes.
1056 */
1057typedef struct png_row_info_struct
1058{
1059 png_uint_32 width; /* width of row */
1060 png_uint_32 rowbytes; /* number of bytes in row */
1061 png_byte color_type; /* color type of row */
1062 png_byte bit_depth; /* bit depth of row */
1063 png_byte channels; /* number of channels (1, 2, 3, or 4) */
1064 png_byte pixel_depth; /* bits per pixel (depth * channels) */
1065} png_row_info;
1066
1067typedef png_row_info FAR * png_row_infop;
1068typedef png_row_info FAR * FAR * png_row_infopp;
1069
1070/* These are the function types for the I/O functions and for the functions
1071 * that allow the user to override the default I/O functions with his or her
1072 * own. The png_error_ptr type should match that of user-supplied warning
1073 * and error functions, while the png_rw_ptr type should match that of the
1074 * user read/write data functions.
1075 */
1076typedef struct png_struct_def png_struct;
1077typedef png_struct FAR * png_structp;
1078
1079typedef void (PNGAPI *png_error_ptr) PNGARG((png_structp, png_const_charp));
1080typedef void (PNGAPI *png_rw_ptr) PNGARG((png_structp, png_bytep, png_size_t));
1081typedef void (PNGAPI *png_flush_ptr) PNGARG((png_structp));
1082typedef void (PNGAPI *png_read_status_ptr) PNGARG((png_structp, png_uint_32,
1083 int));
1084typedef void (PNGAPI *png_write_status_ptr) PNGARG((png_structp, png_uint_32,
1085 int));
1086
1087#ifdef PNG_PROGRESSIVE_READ_SUPPORTED
1088typedef void (PNGAPI *png_progressive_info_ptr) PNGARG((png_structp, png_infop));
1089typedef void (PNGAPI *png_progressive_end_ptr) PNGARG((png_structp, png_infop));
1090typedef void (PNGAPI *png_progressive_row_ptr) PNGARG((png_structp, png_bytep,
1091 png_uint_32, int));
1092#endif
1093
1094#if defined(PNG_READ_USER_TRANSFORM_SUPPORTED) || \
1095 defined(PNG_WRITE_USER_TRANSFORM_SUPPORTED) || \
1096 defined(PNG_LEGACY_SUPPORTED)
1097typedef void (PNGAPI *png_user_transform_ptr) PNGARG((png_structp,
1098 png_row_infop, png_bytep));
1099#endif
1100
1101#if defined(PNG_USER_CHUNKS_SUPPORTED)
1102typedef int (PNGAPI *png_user_chunk_ptr) PNGARG((png_structp, png_unknown_chunkp));
1103#endif
1104#if defined(PNG_UNKNOWN_CHUNKS_SUPPORTED)
1105typedef void (PNGAPI *png_unknown_chunk_ptr) PNGARG((png_structp));
1106#endif
1107
1108/* Transform masks for the high-level interface */
1109#define PNG_TRANSFORM_IDENTITY 0x0000 /* read and write */
1110#define PNG_TRANSFORM_STRIP_16 0x0001 /* read only */
1111#define PNG_TRANSFORM_STRIP_ALPHA 0x0002 /* read only */
1112#define PNG_TRANSFORM_PACKING 0x0004 /* read and write */
1113#define PNG_TRANSFORM_PACKSWAP 0x0008 /* read and write */
1114#define PNG_TRANSFORM_EXPAND 0x0010 /* read only */
1115#define PNG_TRANSFORM_INVERT_MONO 0x0020 /* read and write */
1116#define PNG_TRANSFORM_SHIFT 0x0040 /* read and write */
1117#define PNG_TRANSFORM_BGR 0x0080 /* read and write */
1118#define PNG_TRANSFORM_SWAP_ALPHA 0x0100 /* read and write */
1119#define PNG_TRANSFORM_SWAP_ENDIAN 0x0200 /* read and write */
1120#define PNG_TRANSFORM_INVERT_ALPHA 0x0400 /* read and write */
1121#define PNG_TRANSFORM_STRIP_FILLER 0x0800 /* WRITE only */
1122
1123/* Flags for MNG supported features */
1124#define PNG_FLAG_MNG_EMPTY_PLTE 0x01
1125#define PNG_FLAG_MNG_FILTER_64 0x04
1126#define PNG_ALL_MNG_FEATURES 0x05
1127
1128typedef png_voidp (*png_malloc_ptr) PNGARG((png_structp, png_size_t));
1129typedef void (*png_free_ptr) PNGARG((png_structp, png_voidp));
1130
1131/* The structure that holds the information to read and write PNG files.
1132 * The only people who need to care about what is inside of this are the
1133 * people who will be modifying the library for their own special needs.
1134 * It should NOT be accessed directly by an application, except to store
1135 * the jmp_buf.
1136 */
1137
1138struct png_struct_def
1139{
1140#ifdef PNG_SETJMP_SUPPORTED
1141 jmp_buf jmpbuf; /* used in png_error */
1142#endif
1143 png_error_ptr error_fn; /* function for printing errors and aborting */
1144 png_error_ptr warning_fn; /* function for printing warnings */
1145 png_voidp error_ptr; /* user supplied struct for error functions */
1146 png_rw_ptr write_data_fn; /* function for writing output data */
1147 png_rw_ptr read_data_fn; /* function for reading input data */
1148 png_voidp io_ptr; /* ptr to application struct for I/O functions */
1149
1150#if defined(PNG_READ_USER_TRANSFORM_SUPPORTED)
1151 png_user_transform_ptr read_user_transform_fn; /* user read transform */
1152#endif
1153
1154#if defined(PNG_WRITE_USER_TRANSFORM_SUPPORTED)
1155 png_user_transform_ptr write_user_transform_fn; /* user write transform */
1156#endif
1157
1158/* These were added in libpng-1.0.2 */
1159#if defined(PNG_USER_TRANSFORM_PTR_SUPPORTED)
1160#if defined(PNG_READ_USER_TRANSFORM_SUPPORTED) || \
1161 defined(PNG_WRITE_USER_TRANSFORM_SUPPORTED)
1162 png_voidp user_transform_ptr; /* user supplied struct for user transform */
1163 png_byte user_transform_depth; /* bit depth of user transformed pixels */
1164 png_byte user_transform_channels; /* channels in user transformed pixels */
1165#endif
1166#endif
1167
1168 png_uint_32 mode; /* tells us where we are in the PNG file */
1169 png_uint_32 flags; /* flags indicating various things to libpng */
1170 png_uint_32 transformations; /* which transformations to perform */
1171
1172 z_stream zstream; /* pointer to decompression structure (below) */
1173 png_bytep zbuf; /* buffer for zlib */
1174 png_size_t zbuf_size; /* size of zbuf */
1175 int zlib_level; /* holds zlib compression level */
1176 int zlib_method; /* holds zlib compression method */
1177 int zlib_window_bits; /* holds zlib compression window bits */
1178 int zlib_mem_level; /* holds zlib compression memory level */
1179 int zlib_strategy; /* holds zlib compression strategy */
1180
1181 png_uint_32 width; /* width of image in pixels */
1182 png_uint_32 height; /* height of image in pixels */
1183 png_uint_32 num_rows; /* number of rows in current pass */
1184 png_uint_32 usr_width; /* width of row at start of write */
1185 png_uint_32 rowbytes; /* size of row in bytes */
1186 png_uint_32 irowbytes; /* size of current interlaced row in bytes */
1187 png_uint_32 iwidth; /* width of current interlaced row in pixels */
1188 png_uint_32 row_number; /* current row in interlace pass */
1189 png_bytep prev_row; /* buffer to save previous (unfiltered) row */
1190 png_bytep row_buf; /* buffer to save current (unfiltered) row */
1191#ifndef PNG_NO_WRITE_FILTERING
1192 png_bytep sub_row; /* buffer to save "sub" row when filtering */
1193 png_bytep up_row; /* buffer to save "up" row when filtering */
1194 png_bytep avg_row; /* buffer to save "avg" row when filtering */
1195 png_bytep paeth_row; /* buffer to save "Paeth" row when filtering */
1196#endif
1197 png_row_info row_info; /* used for transformation routines */
1198
1199 png_uint_32 idat_size; /* current IDAT size for read */
1200 png_uint_32 crc; /* current chunk CRC value */
1201 png_colorp palette; /* palette from the input file */
1202 png_uint_16 num_palette; /* number of color entries in palette */
1203 png_uint_16 num_trans; /* number of transparency values */
1204 png_byte chunk_name[5]; /* null-terminated name of current chunk */
1205 png_byte compression; /* file compression type (always 0) */
1206 png_byte filter; /* file filter type (always 0) */
1207 png_byte interlaced; /* PNG_INTERLACE_NONE, PNG_INTERLACE_ADAM7 */
1208 png_byte pass; /* current interlace pass (0 - 6) */
1209 png_byte do_filter; /* row filter flags (see PNG_FILTER_ below ) */
1210 png_byte color_type; /* color type of file */
1211 png_byte bit_depth; /* bit depth of file */
1212 png_byte usr_bit_depth; /* bit depth of users row */
1213 png_byte pixel_depth; /* number of bits per pixel */
1214 png_byte channels; /* number of channels in file */
1215 png_byte usr_channels; /* channels at start of write */
1216 png_byte sig_bytes; /* magic bytes read/written from start of file */
1217
1218#if defined(PNG_READ_FILLER_SUPPORTED) || defined(PNG_WRITE_FILLER_SUPPORTED)
1219#ifdef PNG_LEGACY_SUPPORTED
1220 png_byte filler; /* filler byte for pixel expansion */
1221#else
1222 png_uint_16 filler; /* filler bytes for pixel expansion */
1223#endif
1224#endif
1225
1226#if defined(PNG_bKGD_SUPPORTED)
1227 png_byte background_gamma_type;
1228# ifdef PNG_FLOATING_POINT_SUPPORTED
1229 float background_gamma;
1230# endif
1231 png_color_16 background; /* background color in screen gamma space */
1232#if defined(PNG_READ_GAMMA_SUPPORTED)
1233 png_color_16 background_1; /* background normalized to gamma 1.0 */
1234#endif
1235#endif /* PNG_bKGD_SUPPORTED */
1236
1237#if defined(PNG_WRITE_FLUSH_SUPPORTED)
1238 png_flush_ptr output_flush_fn;/* Function for flushing output */
1239 png_uint_32 flush_dist; /* how many rows apart to flush, 0 - no flush */
1240 png_uint_32 flush_rows; /* number of rows written since last flush */
1241#endif
1242
1243#if defined(PNG_READ_GAMMA_SUPPORTED) || defined(PNG_READ_BACKGROUND_SUPPORTED)
1244 int gamma_shift; /* number of "insignificant" bits 16-bit gamma */
1245#ifdef PNG_FLOATING_POINT_SUPPORTED
1246 float gamma; /* file gamma value */
1247 float screen_gamma; /* screen gamma value (display_exponent) */
1248#endif
1249#endif
1250
1251#if defined(PNG_READ_GAMMA_SUPPORTED) || defined(PNG_READ_BACKGROUND_SUPPORTED)
1252 png_bytep gamma_table; /* gamma table for 8-bit depth files */
1253 png_bytep gamma_from_1; /* converts from 1.0 to screen */
1254 png_bytep gamma_to_1; /* converts from file to 1.0 */
1255 png_uint_16pp gamma_16_table; /* gamma table for 16-bit depth files */
1256 png_uint_16pp gamma_16_from_1; /* converts from 1.0 to screen */
1257 png_uint_16pp gamma_16_to_1; /* converts from file to 1.0 */
1258#endif
1259
1260#if defined(PNG_READ_GAMMA_SUPPORTED) || defined(PNG_sBIT_SUPPORTED)
1261 png_color_8 sig_bit; /* significant bits in each available channel */
1262#endif
1263
1264#if defined(PNG_READ_SHIFT_SUPPORTED) || defined(PNG_WRITE_SHIFT_SUPPORTED)
1265 png_color_8 shift; /* shift for significant bit tranformation */
1266#endif
1267
1268#if defined(PNG_tRNS_SUPPORTED) || defined(PNG_READ_BACKGROUND_SUPPORTED) \
1269 || defined(PNG_READ_EXPAND_SUPPORTED) || defined(PNG_READ_BACKGROUND_SUPPORTED)
1270 png_bytep trans; /* transparency values for paletted files */
1271 png_color_16 trans_values; /* transparency values for non-paletted files */
1272#endif
1273
1274 png_read_status_ptr read_row_fn; /* called after each row is decoded */
1275 png_write_status_ptr write_row_fn; /* called after each row is encoded */
1276#ifdef PNG_PROGRESSIVE_READ_SUPPORTED
1277 png_progressive_info_ptr info_fn; /* called after header data fully read */
1278 png_progressive_row_ptr row_fn; /* called after each prog. row is decoded */
1279 png_progressive_end_ptr end_fn; /* called after image is complete */
1280 png_bytep save_buffer_ptr; /* current location in save_buffer */
1281 png_bytep save_buffer; /* buffer for previously read data */
1282 png_bytep current_buffer_ptr; /* current location in current_buffer */
1283 png_bytep current_buffer; /* buffer for recently used data */
1284 png_uint_32 push_length; /* size of current input chunk */
1285 png_uint_32 skip_length; /* bytes to skip in input data */
1286 png_size_t save_buffer_size; /* amount of data now in save_buffer */
1287 png_size_t save_buffer_max; /* total size of save_buffer */
1288 png_size_t buffer_size; /* total amount of available input data */
1289 png_size_t current_buffer_size; /* amount of data now in current_buffer */
1290 int process_mode; /* what push library is currently doing */
1291 int cur_palette; /* current push library palette index */
1292
1293# if defined(PNG_TEXT_SUPPORTED)
1294 png_size_t current_text_size; /* current size of text input data */
1295 png_size_t current_text_left; /* how much text left to read in input */
1296 png_charp current_text; /* current text chunk buffer */
1297 png_charp current_text_ptr; /* current location in current_text */
1298# endif /* PNG_TEXT_SUPPORTED */
1299#endif /* PNG_PROGRESSIVE_READ_SUPPORTED */
1300
1301#if defined(__TURBOC__) && !defined(_Windows) && !defined(__FLAT__)
1302/* for the Borland special 64K segment handler */
1303 png_bytepp offset_table_ptr;
1304 png_bytep offset_table;
1305 png_uint_16 offset_table_number;
1306 png_uint_16 offset_table_count;
1307 png_uint_16 offset_table_count_free;
1308#endif
1309
1310#if defined(PNG_READ_DITHER_SUPPORTED)
1311 png_bytep palette_lookup; /* lookup table for dithering */
1312 png_bytep dither_index; /* index translation for palette files */
1313#endif
1314
1315#if defined(PNG_READ_DITHER_SUPPORTED) || defined(PNG_hIST_SUPPORTED)
1316 png_uint_16p hist; /* histogram */
1317#endif
1318
1319#if defined(PNG_WRITE_WEIGHTED_FILTER_SUPPORTED)
1320 png_byte heuristic_method; /* heuristic for row filter selection */
1321 png_byte num_prev_filters; /* number of weights for previous rows */
1322 png_bytep prev_filters; /* filter type(s) of previous row(s) */
1323 png_uint_16p filter_weights; /* weight(s) for previous line(s) */
1324 png_uint_16p inv_filter_weights; /* 1/weight(s) for previous line(s) */
1325 png_uint_16p filter_costs; /* relative filter calculation cost */
1326 png_uint_16p inv_filter_costs; /* 1/relative filter calculation cost */
1327#endif
1328
1329#if defined(PNG_TIME_RFC1123_SUPPORTED)
1330 png_charp time_buffer; /* String to hold RFC 1123 time text */
1331#endif
1332
1333/* New members added in libpng-1.0.6 */
1334
1335#ifdef PNG_FREE_ME_SUPPORTED
1336 png_uint_32 free_me; /* flags items libpng is responsible for freeing */
1337#endif
1338
1339#if defined(PNG_USER_CHUNKS_SUPPORTED)
1340 png_voidp user_chunk_ptr;
1341 png_user_chunk_ptr read_user_chunk_fn; /* user read chunk handler */
1342#endif
1343
1344#if defined(PNG_UNKNOWN_CHUNKS_SUPPORTED)
1345 int num_chunk_list;
1346 png_bytep chunk_list;
1347#endif
1348
1349/* New members added in libpng-1.0.3 */
1350#if defined(PNG_READ_RGB_TO_GRAY_SUPPORTED)
1351 png_byte rgb_to_gray_status;
1352 /* These were changed from png_byte in libpng-1.0.6 */
1353 png_uint_16 rgb_to_gray_red_coeff;
1354 png_uint_16 rgb_to_gray_green_coeff;
1355 png_uint_16 rgb_to_gray_blue_coeff;
1356#endif
1357
1358/* New member added in libpng-1.0.4 (renamed in 1.0.9) */
1359#if defined(PNG_MNG_FEATURES_SUPPORTED) || \
1360 defined(PNG_READ_EMPTY_PLTE_SUPPORTED) || \
1361 defined(PNG_WRITE_EMPTY_PLTE_SUPPORTED)
1362/* changed from png_byte to png_uint_32 at version 1.2.0 */
1363#ifdef PNG_1_0_X
1364 png_byte mng_features_permitted;
1365#else
1366 png_uint_32 mng_features_permitted;
1367#endif /* PNG_1_0_X */
1368#endif
1369
1370/* New member added in libpng-1.0.7 */
1371#if defined(PNG_READ_GAMMA_SUPPORTED) || defined(PNG_READ_BACKGROUND_SUPPORTED)
1372 png_fixed_point int_gamma;
1373#endif
1374
1375/* New member added in libpng-1.0.9, ifdef'ed out in 1.0.12, enabled in 1.2.0 */
1376#if defined(PNG_MNG_FEATURES_SUPPORTED)
1377 png_byte filter_type;
1378#endif
1379
1380#if defined(PNG_1_0_X)
1381/* New member added in libpng-1.0.10, ifdef'ed out in 1.2.0 */
1382 png_uint_32 row_buf_size;
1383#endif
1384
1385/* New members added in libpng-1.2.0 */
1386#if defined(PNG_ASSEMBLER_CODE_SUPPORTED)
1387# if !defined(PNG_1_0_X)
1388# if defined(PNG_MMX_CODE_SUPPORTED)
1389 png_byte mmx_bitdepth_threshold;
1390 png_uint_32 mmx_rowbytes_threshold;
1391# endif
1392 png_uint_32 asm_flags;
1393# endif
1394#endif
1395
1396/* New members added in libpng-1.0.2 but first enabled by default in 1.2.0 */
1397#ifdef PNG_USER_MEM_SUPPORTED
1398 png_voidp mem_ptr; /* user supplied struct for mem functions */
1399 png_malloc_ptr malloc_fn; /* function for allocating memory */
1400 png_free_ptr free_fn; /* function for freeing memory */
1401#endif
1402
1403/* New member added in libpng-1.0.13 and 1.2.0 */
1404 png_bytep big_row_buf; /* buffer to save current (unfiltered) row */
1405
1406#if defined(PNG_READ_DITHER_SUPPORTED)
1407/* The following three members were added at version 1.0.14 and 1.2.4 */
1408 png_bytep dither_sort; /* working sort array */
1409 png_bytep index_to_palette; /* where the original index currently is */
1410 /* in the palette */
1411 png_bytep palette_to_index; /* which original index points to this */
1412 /* palette color */
1413#endif
1414
1415/* New members added in libpng-1.0.16 and 1.2.6 */
1416 png_byte compression_type;
1417
1418#ifdef PNG_SET_USER_LIMITS_SUPPORTED
1419 png_uint_32 user_width_max;
1420 png_uint_32 user_height_max;
1421#endif
1422
1423/* New member added in libpng-1.0.25 and 1.2.17 */
1424#if defined(PNG_UNKNOWN_CHUNKS_SUPPORTED)
1425 /* storage for unknown chunk that the library doesn't recognize. */
1426 png_unknown_chunk unknown_chunk;
1427#endif
1428};
1429
1430
1431/* This triggers a compiler error in png.c, if png.c and png.h
1432 * do not agree upon the version number.
1433 */
1434typedef png_structp version_1_2_24;
1435
1436typedef png_struct FAR * FAR * png_structpp;
1437
1438/* Here are the function definitions most commonly used. This is not
1439 * the place to find out how to use libpng. See libpng.txt for the
1440 * full explanation, see example.c for the summary. This just provides
1441 * a simple one line description of the use of each function.
1442 */
1443
1444/* Returns the version number of the library */
1445extern PNG_EXPORT(png_uint_32,png_access_version_number) PNGARG((void));
1446
1447/* Tell lib we have already handled the first <num_bytes> magic bytes.
1448 * Handling more than 8 bytes from the beginning of the file is an error.
1449 */
1450extern PNG_EXPORT(void,png_set_sig_bytes) PNGARG((png_structp png_ptr,
1451 int num_bytes));
1452
1453/* Check sig[start] through sig[start + num_to_check - 1] to see if it's a
1454 * PNG file. Returns zero if the supplied bytes match the 8-byte PNG
1455 * signature, and non-zero otherwise. Having num_to_check == 0 or
1456 * start > 7 will always fail (ie return non-zero).
1457 */
1458extern PNG_EXPORT(int,png_sig_cmp) PNGARG((png_bytep sig, png_size_t start,
1459 png_size_t num_to_check));
1460
1461/* Simple signature checking function. This is the same as calling
1462 * png_check_sig(sig, n) := !png_sig_cmp(sig, 0, n).
1463 */
1464extern PNG_EXPORT(int,png_check_sig) PNGARG((png_bytep sig, int num));
1465
1466/* Allocate and initialize png_ptr struct for reading, and any other memory. */
1467extern PNG_EXPORT(png_structp,png_create_read_struct)
1468 PNGARG((png_const_charp user_png_ver, png_voidp error_ptr,
1469 png_error_ptr error_fn, png_error_ptr warn_fn));
1470
1471/* Allocate and initialize png_ptr struct for writing, and any other memory */
1472extern PNG_EXPORT(png_structp,png_create_write_struct)
1473 PNGARG((png_const_charp user_png_ver, png_voidp error_ptr,
1474 png_error_ptr error_fn, png_error_ptr warn_fn));
1475
1476#ifdef PNG_WRITE_SUPPORTED
1477extern PNG_EXPORT(png_uint_32,png_get_compression_buffer_size)
1478 PNGARG((png_structp png_ptr));
1479#endif
1480
1481#ifdef PNG_WRITE_SUPPORTED
1482extern PNG_EXPORT(void,png_set_compression_buffer_size)
1483 PNGARG((png_structp png_ptr, png_uint_32 size));
1484#endif
1485
1486/* Reset the compression stream */
1487extern PNG_EXPORT(int,png_reset_zstream) PNGARG((png_structp png_ptr));
1488
1489/* New functions added in libpng-1.0.2 (not enabled by default until 1.2.0) */
1490#ifdef PNG_USER_MEM_SUPPORTED
1491extern PNG_EXPORT(png_structp,png_create_read_struct_2)
1492 PNGARG((png_const_charp user_png_ver, png_voidp error_ptr,
1493 png_error_ptr error_fn, png_error_ptr warn_fn, png_voidp mem_ptr,
1494 png_malloc_ptr malloc_fn, png_free_ptr free_fn));
1495extern PNG_EXPORT(png_structp,png_create_write_struct_2)
1496 PNGARG((png_const_charp user_png_ver, png_voidp error_ptr,
1497 png_error_ptr error_fn, png_error_ptr warn_fn, png_voidp mem_ptr,
1498 png_malloc_ptr malloc_fn, png_free_ptr free_fn));
1499#endif
1500
1501/* Write a PNG chunk - size, type, (optional) data, CRC. */
1502extern PNG_EXPORT(void,png_write_chunk) PNGARG((png_structp png_ptr,
1503 png_bytep chunk_name, png_bytep data, png_size_t length));
1504
1505/* Write the start of a PNG chunk - length and chunk name. */
1506extern PNG_EXPORT(void,png_write_chunk_start) PNGARG((png_structp png_ptr,
1507 png_bytep chunk_name, png_uint_32 length));
1508
1509/* Write the data of a PNG chunk started with png_write_chunk_start(). */
1510extern PNG_EXPORT(void,png_write_chunk_data) PNGARG((png_structp png_ptr,
1511 png_bytep data, png_size_t length));
1512
1513/* Finish a chunk started with png_write_chunk_start() (includes CRC). */
1514extern PNG_EXPORT(void,png_write_chunk_end) PNGARG((png_structp png_ptr));
1515
1516/* Allocate and initialize the info structure */
1517extern PNG_EXPORT(png_infop,png_create_info_struct)
1518 PNGARG((png_structp png_ptr));
1519
1520#if defined(PNG_1_0_X) || defined (PNG_1_2_X)
1521/* Initialize the info structure (old interface - DEPRECATED) */
1522extern PNG_EXPORT(void,png_info_init) PNGARG((png_infop info_ptr));
1523#undef png_info_init
1524#define png_info_init(info_ptr) png_info_init_3(&info_ptr,\
1525 png_sizeof(png_info));
1526#endif
1527
1528extern PNG_EXPORT(void,png_info_init_3) PNGARG((png_infopp info_ptr,
1529 png_size_t png_info_struct_size));
1530
1531/* Writes all the PNG information before the image. */
1532extern PNG_EXPORT(void,png_write_info_before_PLTE) PNGARG((png_structp png_ptr,
1533 png_infop info_ptr));
1534extern PNG_EXPORT(void,png_write_info) PNGARG((png_structp png_ptr,
1535 png_infop info_ptr));
1536
1537#ifndef PNG_NO_SEQUENTIAL_READ_SUPPORTED
1538/* read the information before the actual image data. */
1539extern PNG_EXPORT(void,png_read_info) PNGARG((png_structp png_ptr,
1540 png_infop info_ptr));
1541#endif
1542
1543#if defined(PNG_TIME_RFC1123_SUPPORTED)
1544extern PNG_EXPORT(png_charp,png_convert_to_rfc1123)
1545 PNGARG((png_structp png_ptr, png_timep ptime));
1546#endif
1547
1548#if !defined(_WIN32_WCE)
1549/* "time.h" functions are not supported on WindowsCE */
1550#if defined(PNG_WRITE_tIME_SUPPORTED)
1551/* convert from a struct tm to png_time */
1552extern PNG_EXPORT(void,png_convert_from_struct_tm) PNGARG((png_timep ptime,
1553 struct tm FAR * ttime));
1554
1555/* convert from time_t to png_time. Uses gmtime() */
1556extern PNG_EXPORT(void,png_convert_from_time_t) PNGARG((png_timep ptime,
1557 time_t ttime));
1558#endif /* PNG_WRITE_tIME_SUPPORTED */
1559#endif /* _WIN32_WCE */
1560
1561#if defined(PNG_READ_EXPAND_SUPPORTED)
1562/* Expand data to 24-bit RGB, or 8-bit grayscale, with alpha if available. */
1563extern PNG_EXPORT(void,png_set_expand) PNGARG((png_structp png_ptr));
1564#if !defined(PNG_1_0_X)
1565extern PNG_EXPORT(void,png_set_expand_gray_1_2_4_to_8) PNGARG((png_structp
1566 png_ptr));
1567#endif
1568extern PNG_EXPORT(void,png_set_palette_to_rgb) PNGARG((png_structp png_ptr));
1569extern PNG_EXPORT(void,png_set_tRNS_to_alpha) PNGARG((png_structp png_ptr));
1570#if defined(PNG_1_0_X) || defined (PNG_1_2_X)
1571/* Deprecated */
1572extern PNG_EXPORT(void,png_set_gray_1_2_4_to_8) PNGARG((png_structp png_ptr));
1573#endif
1574#endif
1575
1576#if defined(PNG_READ_BGR_SUPPORTED) || defined(PNG_WRITE_BGR_SUPPORTED)
1577/* Use blue, green, red order for pixels. */
1578extern PNG_EXPORT(void,png_set_bgr) PNGARG((png_structp png_ptr));
1579#endif
1580
1581#if defined(PNG_READ_GRAY_TO_RGB_SUPPORTED)
1582/* Expand the grayscale to 24-bit RGB if necessary. */
1583extern PNG_EXPORT(void,png_set_gray_to_rgb) PNGARG((png_structp png_ptr));
1584#endif
1585
1586#if defined(PNG_READ_RGB_TO_GRAY_SUPPORTED)
1587/* Reduce RGB to grayscale. */
1588#ifdef PNG_FLOATING_POINT_SUPPORTED
1589extern PNG_EXPORT(void,png_set_rgb_to_gray) PNGARG((png_structp png_ptr,
1590 int error_action, double red, double green ));
1591#endif
1592extern PNG_EXPORT(void,png_set_rgb_to_gray_fixed) PNGARG((png_structp png_ptr,
1593 int error_action, png_fixed_point red, png_fixed_point green ));
1594extern PNG_EXPORT(png_byte,png_get_rgb_to_gray_status) PNGARG((png_structp
1595 png_ptr));
1596#endif
1597
1598extern PNG_EXPORT(void,png_build_grayscale_palette) PNGARG((int bit_depth,
1599 png_colorp palette));
1600
1601#if defined(PNG_READ_STRIP_ALPHA_SUPPORTED)
1602extern PNG_EXPORT(void,png_set_strip_alpha) PNGARG((png_structp png_ptr));
1603#endif
1604
1605#if defined(PNG_READ_SWAP_ALPHA_SUPPORTED) || \
1606 defined(PNG_WRITE_SWAP_ALPHA_SUPPORTED)
1607extern PNG_EXPORT(void,png_set_swap_alpha) PNGARG((png_structp png_ptr));
1608#endif
1609
1610#if defined(PNG_READ_INVERT_ALPHA_SUPPORTED) || \
1611 defined(PNG_WRITE_INVERT_ALPHA_SUPPORTED)
1612extern PNG_EXPORT(void,png_set_invert_alpha) PNGARG((png_structp png_ptr));
1613#endif
1614
1615#if defined(PNG_READ_FILLER_SUPPORTED) || defined(PNG_WRITE_FILLER_SUPPORTED)
1616/* Add a filler byte to 8-bit Gray or 24-bit RGB images. */
1617extern PNG_EXPORT(void,png_set_filler) PNGARG((png_structp png_ptr,
1618 png_uint_32 filler, int flags));
1619/* The values of the PNG_FILLER_ defines should NOT be changed */
1620#define PNG_FILLER_BEFORE 0
1621#define PNG_FILLER_AFTER 1
1622/* Add an alpha byte to 8-bit Gray or 24-bit RGB images. */
1623#if !defined(PNG_1_0_X)
1624extern PNG_EXPORT(void,png_set_add_alpha) PNGARG((png_structp png_ptr,
1625 png_uint_32 filler, int flags));
1626#endif
1627#endif /* PNG_READ_FILLER_SUPPORTED || PNG_WRITE_FILLER_SUPPORTED */
1628
1629#if defined(PNG_READ_SWAP_SUPPORTED) || defined(PNG_WRITE_SWAP_SUPPORTED)
1630/* Swap bytes in 16-bit depth files. */
1631extern PNG_EXPORT(void,png_set_swap) PNGARG((png_structp png_ptr));
1632#endif
1633
1634#if defined(PNG_READ_PACK_SUPPORTED) || defined(PNG_WRITE_PACK_SUPPORTED)
1635/* Use 1 byte per pixel in 1, 2, or 4-bit depth files. */
1636extern PNG_EXPORT(void,png_set_packing) PNGARG((png_structp png_ptr));
1637#endif
1638
1639#if defined(PNG_READ_PACKSWAP_SUPPORTED) || defined(PNG_WRITE_PACKSWAP_SUPPORTED)
1640/* Swap packing order of pixels in bytes. */
1641extern PNG_EXPORT(void,png_set_packswap) PNGARG((png_structp png_ptr));
1642#endif
1643
1644#if defined(PNG_READ_SHIFT_SUPPORTED) || defined(PNG_WRITE_SHIFT_SUPPORTED)
1645/* Converts files to legal bit depths. */
1646extern PNG_EXPORT(void,png_set_shift) PNGARG((png_structp png_ptr,
1647 png_color_8p true_bits));
1648#endif
1649
1650#if defined(PNG_READ_INTERLACING_SUPPORTED) || \
1651 defined(PNG_WRITE_INTERLACING_SUPPORTED)
1652/* Have the code handle the interlacing. Returns the number of passes. */
1653extern PNG_EXPORT(int,png_set_interlace_handling) PNGARG((png_structp png_ptr));
1654#endif
1655
1656#if defined(PNG_READ_INVERT_SUPPORTED) || defined(PNG_WRITE_INVERT_SUPPORTED)
1657/* Invert monochrome files */
1658extern PNG_EXPORT(void,png_set_invert_mono) PNGARG((png_structp png_ptr));
1659#endif
1660
1661#if defined(PNG_READ_BACKGROUND_SUPPORTED)
1662/* Handle alpha and tRNS by replacing with a background color. */
1663#ifdef PNG_FLOATING_POINT_SUPPORTED
1664extern PNG_EXPORT(void,png_set_background) PNGARG((png_structp png_ptr,
1665 png_color_16p background_color, int background_gamma_code,
1666 int need_expand, double background_gamma));
1667#endif
1668#define PNG_BACKGROUND_GAMMA_UNKNOWN 0
1669#define PNG_BACKGROUND_GAMMA_SCREEN 1
1670#define PNG_BACKGROUND_GAMMA_FILE 2
1671#define PNG_BACKGROUND_GAMMA_UNIQUE 3
1672#endif
1673
1674#if defined(PNG_READ_16_TO_8_SUPPORTED)
1675/* strip the second byte of information from a 16-bit depth file. */
1676extern PNG_EXPORT(void,png_set_strip_16) PNGARG((png_structp png_ptr));
1677#endif
1678
1679#if defined(PNG_READ_DITHER_SUPPORTED)
1680/* Turn on dithering, and reduce the palette to the number of colors available. */
1681extern PNG_EXPORT(void,png_set_dither) PNGARG((png_structp png_ptr,
1682 png_colorp palette, int num_palette, int maximum_colors,
1683 png_uint_16p histogram, int full_dither));
1684#endif
1685
1686#if defined(PNG_READ_GAMMA_SUPPORTED)
1687/* Handle gamma correction. Screen_gamma=(display_exponent) */
1688#ifdef PNG_FLOATING_POINT_SUPPORTED
1689extern PNG_EXPORT(void,png_set_gamma) PNGARG((png_structp png_ptr,
1690 double screen_gamma, double default_file_gamma));
1691#endif
1692#endif
1693
1694#if defined(PNG_1_0_X) || defined (PNG_1_2_X)
1695#if defined(PNG_READ_EMPTY_PLTE_SUPPORTED) || \
1696 defined(PNG_WRITE_EMPTY_PLTE_SUPPORTED)
1697/* Permit or disallow empty PLTE (0: not permitted, 1: permitted) */
1698/* Deprecated and will be removed. Use png_permit_mng_features() instead. */
1699extern PNG_EXPORT(void,png_permit_empty_plte) PNGARG((png_structp png_ptr,
1700 int empty_plte_permitted));
1701#endif
1702#endif
1703
1704#if defined(PNG_WRITE_FLUSH_SUPPORTED)
1705/* Set how many lines between output flushes - 0 for no flushing */
1706extern PNG_EXPORT(void,png_set_flush) PNGARG((png_structp png_ptr, int nrows));
1707/* Flush the current PNG output buffer */
1708extern PNG_EXPORT(void,png_write_flush) PNGARG((png_structp png_ptr));
1709#endif
1710
1711/* optional update palette with requested transformations */
1712extern PNG_EXPORT(void,png_start_read_image) PNGARG((png_structp png_ptr));
1713
1714/* optional call to update the users info structure */
1715extern PNG_EXPORT(void,png_read_update_info) PNGARG((png_structp png_ptr,
1716 png_infop info_ptr));
1717
1718#ifndef PNG_NO_SEQUENTIAL_READ_SUPPORTED
1719/* read one or more rows of image data. */
1720extern PNG_EXPORT(void,png_read_rows) PNGARG((png_structp png_ptr,
1721 png_bytepp row, png_bytepp display_row, png_uint_32 num_rows));
1722#endif
1723
1724#ifndef PNG_NO_SEQUENTIAL_READ_SUPPORTED
1725/* read a row of data. */
1726extern PNG_EXPORT(void,png_read_row) PNGARG((png_structp png_ptr,
1727 png_bytep row,
1728 png_bytep display_row));
1729#endif
1730
1731#ifndef PNG_NO_SEQUENTIAL_READ_SUPPORTED
1732/* read the whole image into memory at once. */
1733extern PNG_EXPORT(void,png_read_image) PNGARG((png_structp png_ptr,
1734 png_bytepp image));
1735#endif
1736
1737/* write a row of image data */
1738extern PNG_EXPORT(void,png_write_row) PNGARG((png_structp png_ptr,
1739 png_bytep row));
1740
1741/* write a few rows of image data */
1742extern PNG_EXPORT(void,png_write_rows) PNGARG((png_structp png_ptr,
1743 png_bytepp row, png_uint_32 num_rows));
1744
1745/* write the image data */
1746extern PNG_EXPORT(void,png_write_image) PNGARG((png_structp png_ptr,
1747 png_bytepp image));
1748
1749/* writes the end of the PNG file. */
1750extern PNG_EXPORT(void,png_write_end) PNGARG((png_structp png_ptr,
1751 png_infop info_ptr));
1752
1753#ifndef PNG_NO_SEQUENTIAL_READ_SUPPORTED
1754/* read the end of the PNG file. */
1755extern PNG_EXPORT(void,png_read_end) PNGARG((png_structp png_ptr,
1756 png_infop info_ptr));
1757#endif
1758
1759/* free any memory associated with the png_info_struct */
1760extern PNG_EXPORT(void,png_destroy_info_struct) PNGARG((png_structp png_ptr,
1761 png_infopp info_ptr_ptr));
1762
1763/* free any memory associated with the png_struct and the png_info_structs */
1764extern PNG_EXPORT(void,png_destroy_read_struct) PNGARG((png_structpp
1765 png_ptr_ptr, png_infopp info_ptr_ptr, png_infopp end_info_ptr_ptr));
1766
1767/* free all memory used by the read (old method - NOT DLL EXPORTED) */
1768/* Debian note: exporting as it is required by legacy applications */
1769extern PNG_EXPORT(void,png_read_destroy) PNGARG((png_structp png_ptr, png_infop info_ptr,
1770 png_infop end_info_ptr));
1771
1772/* free any memory associated with the png_struct and the png_info_structs */
1773extern PNG_EXPORT(void,png_destroy_write_struct)
1774 PNGARG((png_structpp png_ptr_ptr, png_infopp info_ptr_ptr));
1775
1776/* free any memory used in png_ptr struct (old method - NOT DLL EXPORTED) */
1777/* Debian note: exporting as it is required by legacy applications */
1778extern PNG_EXPORT(void,png_write_destroy) PNGARG((png_structp png_ptr));
1779
1780/* set the libpng method of handling chunk CRC errors */
1781extern PNG_EXPORT(void,png_set_crc_action) PNGARG((png_structp png_ptr,
1782 int crit_action, int ancil_action));
1783
1784/* Values for png_set_crc_action() to say how to handle CRC errors in
1785 * ancillary and critical chunks, and whether to use the data contained
1786 * therein. Note that it is impossible to "discard" data in a critical
1787 * chunk. For versions prior to 0.90, the action was always error/quit,
1788 * whereas in version 0.90 and later, the action for CRC errors in ancillary
1789 * chunks is warn/discard. These values should NOT be changed.
1790 *
1791 * value action:critical action:ancillary
1792 */
1793#define PNG_CRC_DEFAULT 0 /* error/quit warn/discard data */
1794#define PNG_CRC_ERROR_QUIT 1 /* error/quit error/quit */
1795#define PNG_CRC_WARN_DISCARD 2 /* (INVALID) warn/discard data */
1796#define PNG_CRC_WARN_USE 3 /* warn/use data warn/use data */
1797#define PNG_CRC_QUIET_USE 4 /* quiet/use data quiet/use data */
1798#define PNG_CRC_NO_CHANGE 5 /* use current value use current value */
1799
1800/* These functions give the user control over the scan-line filtering in
1801 * libpng and the compression methods used by zlib. These functions are
1802 * mainly useful for testing, as the defaults should work with most users.
1803 * Those users who are tight on memory or want faster performance at the
1804 * expense of compression can modify them. See the compression library
1805 * header file (zlib.h) for an explination of the compression functions.
1806 */
1807
1808/* set the filtering method(s) used by libpng. Currently, the only valid
1809 * value for "method" is 0.
1810 */
1811extern PNG_EXPORT(void,png_set_filter) PNGARG((png_structp png_ptr, int method,
1812 int filters));
1813
1814/* Flags for png_set_filter() to say which filters to use. The flags
1815 * are chosen so that they don't conflict with real filter types
1816 * below, in case they are supplied instead of the #defined constants.
1817 * These values should NOT be changed.
1818 */
1819#define PNG_NO_FILTERS 0x00
1820#define PNG_FILTER_NONE 0x08
1821#define PNG_FILTER_SUB 0x10
1822#define PNG_FILTER_UP 0x20
1823#define PNG_FILTER_AVG 0x40
1824#define PNG_FILTER_PAETH 0x80
1825#define PNG_ALL_FILTERS (PNG_FILTER_NONE | PNG_FILTER_SUB | PNG_FILTER_UP | \
1826 PNG_FILTER_AVG | PNG_FILTER_PAETH)
1827
1828/* Filter values (not flags) - used in pngwrite.c, pngwutil.c for now.
1829 * These defines should NOT be changed.
1830 */
1831#define PNG_FILTER_VALUE_NONE 0
1832#define PNG_FILTER_VALUE_SUB 1
1833#define PNG_FILTER_VALUE_UP 2
1834#define PNG_FILTER_VALUE_AVG 3
1835#define PNG_FILTER_VALUE_PAETH 4
1836#define PNG_FILTER_VALUE_LAST 5
1837
1838#if defined(PNG_WRITE_WEIGHTED_FILTER_SUPPORTED) /* EXPERIMENTAL */
1839/* The "heuristic_method" is given by one of the PNG_FILTER_HEURISTIC_
1840 * defines, either the default (minimum-sum-of-absolute-differences), or
1841 * the experimental method (weighted-minimum-sum-of-absolute-differences).
1842 *
1843 * Weights are factors >= 1.0, indicating how important it is to keep the
1844 * filter type consistent between rows. Larger numbers mean the current
1845 * filter is that many times as likely to be the same as the "num_weights"
1846 * previous filters. This is cumulative for each previous row with a weight.
1847 * There needs to be "num_weights" values in "filter_weights", or it can be
1848 * NULL if the weights aren't being specified. Weights have no influence on
1849 * the selection of the first row filter. Well chosen weights can (in theory)
1850 * improve the compression for a given image.
1851 *
1852 * Costs are factors >= 1.0 indicating the relative decoding costs of a
1853 * filter type. Higher costs indicate more decoding expense, and are
1854 * therefore less likely to be selected over a filter with lower computational
1855 * costs. There needs to be a value in "filter_costs" for each valid filter
1856 * type (given by PNG_FILTER_VALUE_LAST), or it can be NULL if you aren't
1857 * setting the costs. Costs try to improve the speed of decompression without
1858 * unduly increasing the compressed image size.
1859 *
1860 * A negative weight or cost indicates the default value is to be used, and
1861 * values in the range [0.0, 1.0) indicate the value is to remain unchanged.
1862 * The default values for both weights and costs are currently 1.0, but may
1863 * change if good general weighting/cost heuristics can be found. If both
1864 * the weights and costs are set to 1.0, this degenerates the WEIGHTED method
1865 * to the UNWEIGHTED method, but with added encoding time/computation.
1866 */
1867#ifdef PNG_FLOATING_POINT_SUPPORTED
1868extern PNG_EXPORT(void,png_set_filter_heuristics) PNGARG((png_structp png_ptr,
1869 int heuristic_method, int num_weights, png_doublep filter_weights,
1870 png_doublep filter_costs));
1871#endif
1872#endif /* PNG_WRITE_WEIGHTED_FILTER_SUPPORTED */
1873
1874/* Heuristic used for row filter selection. These defines should NOT be
1875 * changed.
1876 */
1877#define PNG_FILTER_HEURISTIC_DEFAULT 0 /* Currently "UNWEIGHTED" */
1878#define PNG_FILTER_HEURISTIC_UNWEIGHTED 1 /* Used by libpng < 0.95 */
1879#define PNG_FILTER_HEURISTIC_WEIGHTED 2 /* Experimental feature */
1880#define PNG_FILTER_HEURISTIC_LAST 3 /* Not a valid value */
1881
1882/* Set the library compression level. Currently, valid values range from
1883 * 0 - 9, corresponding directly to the zlib compression levels 0 - 9
1884 * (0 - no compression, 9 - "maximal" compression). Note that tests have
1885 * shown that zlib compression levels 3-6 usually perform as well as level 9
1886 * for PNG images, and do considerably fewer caclulations. In the future,
1887 * these values may not correspond directly to the zlib compression levels.
1888 */
1889extern PNG_EXPORT(void,png_set_compression_level) PNGARG((png_structp png_ptr,
1890 int level));
1891
1892extern PNG_EXPORT(void,png_set_compression_mem_level)
1893 PNGARG((png_structp png_ptr, int mem_level));
1894
1895extern PNG_EXPORT(void,png_set_compression_strategy)
1896 PNGARG((png_structp png_ptr, int strategy));
1897
1898extern PNG_EXPORT(void,png_set_compression_window_bits)
1899 PNGARG((png_structp png_ptr, int window_bits));
1900
1901extern PNG_EXPORT(void,png_set_compression_method) PNGARG((png_structp png_ptr,
1902 int method));
1903
1904/* These next functions are called for input/output, memory, and error
1905 * handling. They are in the file pngrio.c, pngwio.c, and pngerror.c,
1906 * and call standard C I/O routines such as fread(), fwrite(), and
1907 * fprintf(). These functions can be made to use other I/O routines
1908 * at run time for those applications that need to handle I/O in a
1909 * different manner by calling png_set_???_fn(). See libpng.txt for
1910 * more information.
1911 */
1912
1913#if !defined(PNG_NO_STDIO)
1914/* Initialize the input/output for the PNG file to the default functions. */
1915extern PNG_EXPORT(void,png_init_io) PNGARG((png_structp png_ptr, png_FILE_p fp));
1916#endif
1917
1918/* Replace the (error and abort), and warning functions with user
1919 * supplied functions. If no messages are to be printed you must still
1920 * write and use replacement functions. The replacement error_fn should
1921 * still do a longjmp to the last setjmp location if you are using this
1922 * method of error handling. If error_fn or warning_fn is NULL, the
1923 * default function will be used.
1924 */
1925
1926extern PNG_EXPORT(void,png_set_error_fn) PNGARG((png_structp png_ptr,
1927 png_voidp error_ptr, png_error_ptr error_fn, png_error_ptr warning_fn));
1928
1929/* Return the user pointer associated with the error functions */
1930extern PNG_EXPORT(png_voidp,png_get_error_ptr) PNGARG((png_structp png_ptr));
1931
1932/* Replace the default data output functions with a user supplied one(s).
1933 * If buffered output is not used, then output_flush_fn can be set to NULL.
1934 * If PNG_WRITE_FLUSH_SUPPORTED is not defined at libpng compile time
1935 * output_flush_fn will be ignored (and thus can be NULL).
1936 */
1937extern PNG_EXPORT(void,png_set_write_fn) PNGARG((png_structp png_ptr,
1938 png_voidp io_ptr, png_rw_ptr write_data_fn, png_flush_ptr output_flush_fn));
1939
1940/* Replace the default data input function with a user supplied one. */
1941extern PNG_EXPORT(void,png_set_read_fn) PNGARG((png_structp png_ptr,
1942 png_voidp io_ptr, png_rw_ptr read_data_fn));
1943
1944/* Return the user pointer associated with the I/O functions */
1945extern PNG_EXPORT(png_voidp,png_get_io_ptr) PNGARG((png_structp png_ptr));
1946
1947extern PNG_EXPORT(void,png_set_read_status_fn) PNGARG((png_structp png_ptr,
1948 png_read_status_ptr read_row_fn));
1949
1950extern PNG_EXPORT(void,png_set_write_status_fn) PNGARG((png_structp png_ptr,
1951 png_write_status_ptr write_row_fn));
1952
1953#ifdef PNG_USER_MEM_SUPPORTED
1954/* Replace the default memory allocation functions with user supplied one(s). */
1955extern PNG_EXPORT(void,png_set_mem_fn) PNGARG((png_structp png_ptr,
1956 png_voidp mem_ptr, png_malloc_ptr malloc_fn, png_free_ptr free_fn));
1957/* Return the user pointer associated with the memory functions */
1958extern PNG_EXPORT(png_voidp,png_get_mem_ptr) PNGARG((png_structp png_ptr));
1959#endif
1960
1961#if defined(PNG_READ_USER_TRANSFORM_SUPPORTED) || \
1962 defined(PNG_LEGACY_SUPPORTED)
1963extern PNG_EXPORT(void,png_set_read_user_transform_fn) PNGARG((png_structp
1964 png_ptr, png_user_transform_ptr read_user_transform_fn));
1965#endif
1966
1967#if defined(PNG_WRITE_USER_TRANSFORM_SUPPORTED) || \
1968 defined(PNG_LEGACY_SUPPORTED)
1969extern PNG_EXPORT(void,png_set_write_user_transform_fn) PNGARG((png_structp
1970 png_ptr, png_user_transform_ptr write_user_transform_fn));
1971#endif
1972
1973#if defined(PNG_READ_USER_TRANSFORM_SUPPORTED) || \
1974 defined(PNG_WRITE_USER_TRANSFORM_SUPPORTED) || \
1975 defined(PNG_LEGACY_SUPPORTED)
1976extern PNG_EXPORT(void,png_set_user_transform_info) PNGARG((png_structp
1977 png_ptr, png_voidp user_transform_ptr, int user_transform_depth,
1978 int user_transform_channels));
1979/* Return the user pointer associated with the user transform functions */
1980extern PNG_EXPORT(png_voidp,png_get_user_transform_ptr)
1981 PNGARG((png_structp png_ptr));
1982#endif
1983
1984#ifdef PNG_USER_CHUNKS_SUPPORTED
1985extern PNG_EXPORT(void,png_set_read_user_chunk_fn) PNGARG((png_structp png_ptr,
1986 png_voidp user_chunk_ptr, png_user_chunk_ptr read_user_chunk_fn));
1987extern PNG_EXPORT(png_voidp,png_get_user_chunk_ptr) PNGARG((png_structp
1988 png_ptr));
1989#endif
1990
1991#ifdef PNG_PROGRESSIVE_READ_SUPPORTED
1992/* Sets the function callbacks for the push reader, and a pointer to a
1993 * user-defined structure available to the callback functions.
1994 */
1995extern PNG_EXPORT(void,png_set_progressive_read_fn) PNGARG((png_structp png_ptr,
1996 png_voidp progressive_ptr,
1997 png_progressive_info_ptr info_fn, png_progressive_row_ptr row_fn,
1998 png_progressive_end_ptr end_fn));
1999
2000/* returns the user pointer associated with the push read functions */
2001extern PNG_EXPORT(png_voidp,png_get_progressive_ptr)
2002 PNGARG((png_structp png_ptr));
2003
2004/* function to be called when data becomes available */
2005extern PNG_EXPORT(void,png_process_data) PNGARG((png_structp png_ptr,
2006 png_infop info_ptr, png_bytep buffer, png_size_t buffer_size));
2007
2008/* function that combines rows. Not very much different than the
2009 * png_combine_row() call. Is this even used?????
2010 */
2011extern PNG_EXPORT(void,png_progressive_combine_row) PNGARG((png_structp png_ptr,
2012 png_bytep old_row, png_bytep new_row));
2013#endif /* PNG_PROGRESSIVE_READ_SUPPORTED */
2014
2015extern PNG_EXPORT(png_voidp,png_malloc) PNGARG((png_structp png_ptr,
2016 png_uint_32 size));
2017
2018#if defined(PNG_1_0_X)
2019# define png_malloc_warn png_malloc
2020#else
2021/* Added at libpng version 1.2.4 */
2022extern PNG_EXPORT(png_voidp,png_malloc_warn) PNGARG((png_structp png_ptr,
2023 png_uint_32 size));
2024#endif
2025
2026/* frees a pointer allocated by png_malloc() */
2027extern PNG_EXPORT(void,png_free) PNGARG((png_structp png_ptr, png_voidp ptr));
2028
2029#if defined(PNG_1_0_X)
2030/* Function to allocate memory for zlib. */
2031extern PNG_EXPORT(voidpf,png_zalloc) PNGARG((voidpf png_ptr, uInt items,
2032 uInt size));
2033
2034/* Function to free memory for zlib */
2035extern PNG_EXPORT(void,png_zfree) PNGARG((voidpf png_ptr, voidpf ptr));
2036#endif
2037
2038/* Free data that was allocated internally */
2039extern PNG_EXPORT(void,png_free_data) PNGARG((png_structp png_ptr,
2040 png_infop info_ptr, png_uint_32 free_me, int num));
2041#ifdef PNG_FREE_ME_SUPPORTED
2042/* Reassign responsibility for freeing existing data, whether allocated
2043 * by libpng or by the application */
2044extern PNG_EXPORT(void,png_data_freer) PNGARG((png_structp png_ptr,
2045 png_infop info_ptr, int freer, png_uint_32 mask));
2046#endif
2047/* assignments for png_data_freer */
2048#define PNG_DESTROY_WILL_FREE_DATA 1
2049#define PNG_SET_WILL_FREE_DATA 1
2050#define PNG_USER_WILL_FREE_DATA 2
2051/* Flags for png_ptr->free_me and info_ptr->free_me */
2052#define PNG_FREE_HIST 0x0008
2053#define PNG_FREE_ICCP 0x0010
2054#define PNG_FREE_SPLT 0x0020
2055#define PNG_FREE_ROWS 0x0040
2056#define PNG_FREE_PCAL 0x0080
2057#define PNG_FREE_SCAL 0x0100
2058#define PNG_FREE_UNKN 0x0200
2059#define PNG_FREE_LIST 0x0400
2060#define PNG_FREE_PLTE 0x1000
2061#define PNG_FREE_TRNS 0x2000
2062#define PNG_FREE_TEXT 0x4000
2063#define PNG_FREE_ALL 0x7fff
2064#define PNG_FREE_MUL 0x4220 /* PNG_FREE_SPLT|PNG_FREE_TEXT|PNG_FREE_UNKN */
2065
2066#ifdef PNG_USER_MEM_SUPPORTED
2067extern PNG_EXPORT(png_voidp,png_malloc_default) PNGARG((png_structp png_ptr,
2068 png_uint_32 size));
2069extern PNG_EXPORT(void,png_free_default) PNGARG((png_structp png_ptr,
2070 png_voidp ptr));
2071#endif
2072
2073extern PNG_EXPORT(png_voidp,png_memcpy_check) PNGARG((png_structp png_ptr,
2074 png_voidp s1, png_voidp s2, png_uint_32 size));
2075
2076extern PNG_EXPORT(png_voidp,png_memset_check) PNGARG((png_structp png_ptr,
2077 png_voidp s1, int value, png_uint_32 size));
2078
2079#if defined(USE_FAR_KEYWORD) /* memory model conversion function */
2080extern void *png_far_to_near PNGARG((png_structp png_ptr,png_voidp ptr,
2081 int check));
2082#endif /* USE_FAR_KEYWORD */
2083
2084#ifndef PNG_NO_ERROR_TEXT
2085/* Fatal error in PNG image of libpng - can't continue */
2086extern PNG_EXPORT(void,png_error) PNGARG((png_structp png_ptr,
2087 png_const_charp error_message));
2088
2089/* The same, but the chunk name is prepended to the error string. */
2090extern PNG_EXPORT(void,png_chunk_error) PNGARG((png_structp png_ptr,
2091 png_const_charp error_message));
2092#else
2093/* Fatal error in PNG image of libpng - can't continue */
2094extern PNG_EXPORT(void,png_err) PNGARG((png_structp png_ptr));
2095#endif
2096
2097#ifndef PNG_NO_WARNINGS
2098/* Non-fatal error in libpng. Can continue, but may have a problem. */
2099extern PNG_EXPORT(void,png_warning) PNGARG((png_structp png_ptr,
2100 png_const_charp warning_message));
2101
2102#ifdef PNG_READ_SUPPORTED
2103/* Non-fatal error in libpng, chunk name is prepended to message. */
2104extern PNG_EXPORT(void,png_chunk_warning) PNGARG((png_structp png_ptr,
2105 png_const_charp warning_message));
2106#endif /* PNG_READ_SUPPORTED */
2107#endif /* PNG_NO_WARNINGS */
2108
2109/* The png_set_<chunk> functions are for storing values in the png_info_struct.
2110 * Similarly, the png_get_<chunk> calls are used to read values from the
2111 * png_info_struct, either storing the parameters in the passed variables, or
2112 * setting pointers into the png_info_struct where the data is stored. The
2113 * png_get_<chunk> functions return a non-zero value if the data was available
2114 * in info_ptr, or return zero and do not change any of the parameters if the
2115 * data was not available.
2116 *
2117 * These functions should be used instead of directly accessing png_info
2118 * to avoid problems with future changes in the size and internal layout of
2119 * png_info_struct.
2120 */
2121/* Returns "flag" if chunk data is valid in info_ptr. */
2122extern PNG_EXPORT(png_uint_32,png_get_valid) PNGARG((png_structp png_ptr,
2123png_infop info_ptr, png_uint_32 flag));
2124
2125/* Returns number of bytes needed to hold a transformed row. */
2126extern PNG_EXPORT(png_uint_32,png_get_rowbytes) PNGARG((png_structp png_ptr,
2127png_infop info_ptr));
2128
2129#if defined(PNG_INFO_IMAGE_SUPPORTED)
2130/* Returns row_pointers, which is an array of pointers to scanlines that was
2131returned from png_read_png(). */
2132extern PNG_EXPORT(png_bytepp,png_get_rows) PNGARG((png_structp png_ptr,
2133png_infop info_ptr));
2134/* Set row_pointers, which is an array of pointers to scanlines for use
2135by png_write_png(). */
2136extern PNG_EXPORT(void,png_set_rows) PNGARG((png_structp png_ptr,
2137 png_infop info_ptr, png_bytepp row_pointers));
2138#endif
2139
2140/* Returns number of color channels in image. */
2141extern PNG_EXPORT(png_byte,png_get_channels) PNGARG((png_structp png_ptr,
2142png_infop info_ptr));
2143
2144#ifdef PNG_EASY_ACCESS_SUPPORTED
2145/* Returns image width in pixels. */
2146extern PNG_EXPORT(png_uint_32, png_get_image_width) PNGARG((png_structp
2147png_ptr, png_infop info_ptr));
2148
2149/* Returns image height in pixels. */
2150extern PNG_EXPORT(png_uint_32, png_get_image_height) PNGARG((png_structp
2151png_ptr, png_infop info_ptr));
2152
2153/* Returns image bit_depth. */
2154extern PNG_EXPORT(png_byte, png_get_bit_depth) PNGARG((png_structp
2155png_ptr, png_infop info_ptr));
2156
2157/* Returns image color_type. */
2158extern PNG_EXPORT(png_byte, png_get_color_type) PNGARG((png_structp
2159png_ptr, png_infop info_ptr));
2160
2161/* Returns image filter_type. */
2162extern PNG_EXPORT(png_byte, png_get_filter_type) PNGARG((png_structp
2163png_ptr, png_infop info_ptr));
2164
2165/* Returns image interlace_type. */
2166extern PNG_EXPORT(png_byte, png_get_interlace_type) PNGARG((png_structp
2167png_ptr, png_infop info_ptr));
2168
2169/* Returns image compression_type. */
2170extern PNG_EXPORT(png_byte, png_get_compression_type) PNGARG((png_structp
2171png_ptr, png_infop info_ptr));
2172
2173/* Returns image resolution in pixels per meter, from pHYs chunk data. */
2174extern PNG_EXPORT(png_uint_32, png_get_pixels_per_meter) PNGARG((png_structp
2175png_ptr, png_infop info_ptr));
2176extern PNG_EXPORT(png_uint_32, png_get_x_pixels_per_meter) PNGARG((png_structp
2177png_ptr, png_infop info_ptr));
2178extern PNG_EXPORT(png_uint_32, png_get_y_pixels_per_meter) PNGARG((png_structp
2179png_ptr, png_infop info_ptr));
2180
2181/* Returns pixel aspect ratio, computed from pHYs chunk data. */
2182#ifdef PNG_FLOATING_POINT_SUPPORTED
2183extern PNG_EXPORT(float, png_get_pixel_aspect_ratio) PNGARG((png_structp
2184png_ptr, png_infop info_ptr));
2185#endif
2186
2187/* Returns image x, y offset in pixels or microns, from oFFs chunk data. */
2188extern PNG_EXPORT(png_int_32, png_get_x_offset_pixels) PNGARG((png_structp
2189png_ptr, png_infop info_ptr));
2190extern PNG_EXPORT(png_int_32, png_get_y_offset_pixels) PNGARG((png_structp
2191png_ptr, png_infop info_ptr));
2192extern PNG_EXPORT(png_int_32, png_get_x_offset_microns) PNGARG((png_structp
2193png_ptr, png_infop info_ptr));
2194extern PNG_EXPORT(png_int_32, png_get_y_offset_microns) PNGARG((png_structp
2195png_ptr, png_infop info_ptr));
2196
2197#endif /* PNG_EASY_ACCESS_SUPPORTED */
2198
2199/* Returns pointer to signature string read from PNG header */
2200extern PNG_EXPORT(png_bytep,png_get_signature) PNGARG((png_structp png_ptr,
2201png_infop info_ptr));
2202
2203#if defined(PNG_bKGD_SUPPORTED)
2204extern PNG_EXPORT(png_uint_32,png_get_bKGD) PNGARG((png_structp png_ptr,
2205 png_infop info_ptr, png_color_16p *background));
2206#endif
2207
2208#if defined(PNG_bKGD_SUPPORTED)
2209extern PNG_EXPORT(void,png_set_bKGD) PNGARG((png_structp png_ptr,
2210 png_infop info_ptr, png_color_16p background));
2211#endif
2212
2213#if defined(PNG_cHRM_SUPPORTED)
2214#ifdef PNG_FLOATING_POINT_SUPPORTED
2215extern PNG_EXPORT(png_uint_32,png_get_cHRM) PNGARG((png_structp png_ptr,
2216 png_infop info_ptr, double *white_x, double *white_y, double *red_x,
2217 double *red_y, double *green_x, double *green_y, double *blue_x,
2218 double *blue_y));
2219#endif
2220#ifdef PNG_FIXED_POINT_SUPPORTED
2221extern PNG_EXPORT(png_uint_32,png_get_cHRM_fixed) PNGARG((png_structp png_ptr,
2222 png_infop info_ptr, png_fixed_point *int_white_x, png_fixed_point
2223 *int_white_y, png_fixed_point *int_red_x, png_fixed_point *int_red_y,
2224 png_fixed_point *int_green_x, png_fixed_point *int_green_y, png_fixed_point
2225 *int_blue_x, png_fixed_point *int_blue_y));
2226#endif
2227#endif
2228
2229#if defined(PNG_cHRM_SUPPORTED)
2230#ifdef PNG_FLOATING_POINT_SUPPORTED
2231extern PNG_EXPORT(void,png_set_cHRM) PNGARG((png_structp png_ptr,
2232 png_infop info_ptr, double white_x, double white_y, double red_x,
2233 double red_y, double green_x, double green_y, double blue_x, double blue_y));
2234#endif
2235#ifdef PNG_FIXED_POINT_SUPPORTED
2236extern PNG_EXPORT(void,png_set_cHRM_fixed) PNGARG((png_structp png_ptr,
2237 png_infop info_ptr, png_fixed_point int_white_x, png_fixed_point int_white_y,
2238 png_fixed_point int_red_x, png_fixed_point int_red_y, png_fixed_point
2239 int_green_x, png_fixed_point int_green_y, png_fixed_point int_blue_x,
2240 png_fixed_point int_blue_y));
2241#endif
2242#endif
2243
2244#if defined(PNG_gAMA_SUPPORTED)
2245#ifdef PNG_FLOATING_POINT_SUPPORTED
2246extern PNG_EXPORT(png_uint_32,png_get_gAMA) PNGARG((png_structp png_ptr,
2247 png_infop info_ptr, double *file_gamma));
2248#endif
2249extern PNG_EXPORT(png_uint_32,png_get_gAMA_fixed) PNGARG((png_structp png_ptr,
2250 png_infop info_ptr, png_fixed_point *int_file_gamma));
2251#endif
2252
2253#if defined(PNG_gAMA_SUPPORTED)
2254#ifdef PNG_FLOATING_POINT_SUPPORTED
2255extern PNG_EXPORT(void,png_set_gAMA) PNGARG((png_structp png_ptr,
2256 png_infop info_ptr, double file_gamma));
2257#endif
2258extern PNG_EXPORT(void,png_set_gAMA_fixed) PNGARG((png_structp png_ptr,
2259 png_infop info_ptr, png_fixed_point int_file_gamma));
2260#endif
2261
2262#if defined(PNG_hIST_SUPPORTED)
2263extern PNG_EXPORT(png_uint_32,png_get_hIST) PNGARG((png_structp png_ptr,
2264 png_infop info_ptr, png_uint_16p *hist));
2265#endif
2266
2267#if defined(PNG_hIST_SUPPORTED)
2268extern PNG_EXPORT(void,png_set_hIST) PNGARG((png_structp png_ptr,
2269 png_infop info_ptr, png_uint_16p hist));
2270#endif
2271
2272extern PNG_EXPORT(png_uint_32,png_get_IHDR) PNGARG((png_structp png_ptr,
2273 png_infop info_ptr, png_uint_32 *width, png_uint_32 *height,
2274 int *bit_depth, int *color_type, int *interlace_method,
2275 int *compression_method, int *filter_method));
2276
2277extern PNG_EXPORT(void,png_set_IHDR) PNGARG((png_structp png_ptr,
2278 png_infop info_ptr, png_uint_32 width, png_uint_32 height, int bit_depth,
2279 int color_type, int interlace_method, int compression_method,
2280 int filter_method));
2281
2282#if defined(PNG_oFFs_SUPPORTED)
2283extern PNG_EXPORT(png_uint_32,png_get_oFFs) PNGARG((png_structp png_ptr,
2284 png_infop info_ptr, png_int_32 *offset_x, png_int_32 *offset_y,
2285 int *unit_type));
2286#endif
2287
2288#if defined(PNG_oFFs_SUPPORTED)
2289extern PNG_EXPORT(void,png_set_oFFs) PNGARG((png_structp png_ptr,
2290 png_infop info_ptr, png_int_32 offset_x, png_int_32 offset_y,
2291 int unit_type));
2292#endif
2293
2294#if defined(PNG_pCAL_SUPPORTED)
2295extern PNG_EXPORT(png_uint_32,png_get_pCAL) PNGARG((png_structp png_ptr,
2296 png_infop info_ptr, png_charp *purpose, png_int_32 *X0, png_int_32 *X1,
2297 int *type, int *nparams, png_charp *units, png_charpp *params));
2298#endif
2299
2300#if defined(PNG_pCAL_SUPPORTED)
2301extern PNG_EXPORT(void,png_set_pCAL) PNGARG((png_structp png_ptr,
2302 png_infop info_ptr, png_charp purpose, png_int_32 X0, png_int_32 X1,
2303 int type, int nparams, png_charp units, png_charpp params));
2304#endif
2305
2306#if defined(PNG_pHYs_SUPPORTED)
2307extern PNG_EXPORT(png_uint_32,png_get_pHYs) PNGARG((png_structp png_ptr,
2308 png_infop info_ptr, png_uint_32 *res_x, png_uint_32 *res_y, int *unit_type));
2309#endif
2310
2311#if defined(PNG_pHYs_SUPPORTED)
2312extern PNG_EXPORT(void,png_set_pHYs) PNGARG((png_structp png_ptr,
2313 png_infop info_ptr, png_uint_32 res_x, png_uint_32 res_y, int unit_type));
2314#endif
2315
2316extern PNG_EXPORT(png_uint_32,png_get_PLTE) PNGARG((png_structp png_ptr,
2317 png_infop info_ptr, png_colorp *palette, int *num_palette));
2318
2319extern PNG_EXPORT(void,png_set_PLTE) PNGARG((png_structp png_ptr,
2320 png_infop info_ptr, png_colorp palette, int num_palette));
2321
2322#if defined(PNG_sBIT_SUPPORTED)
2323extern PNG_EXPORT(png_uint_32,png_get_sBIT) PNGARG((png_structp png_ptr,
2324 png_infop info_ptr, png_color_8p *sig_bit));
2325#endif
2326
2327#if defined(PNG_sBIT_SUPPORTED)
2328extern PNG_EXPORT(void,png_set_sBIT) PNGARG((png_structp png_ptr,
2329 png_infop info_ptr, png_color_8p sig_bit));
2330#endif
2331
2332#if defined(PNG_sRGB_SUPPORTED)
2333extern PNG_EXPORT(png_uint_32,png_get_sRGB) PNGARG((png_structp png_ptr,
2334 png_infop info_ptr, int *intent));
2335#endif
2336
2337#if defined(PNG_sRGB_SUPPORTED)
2338extern PNG_EXPORT(void,png_set_sRGB) PNGARG((png_structp png_ptr,
2339 png_infop info_ptr, int intent));
2340extern PNG_EXPORT(void,png_set_sRGB_gAMA_and_cHRM) PNGARG((png_structp png_ptr,
2341 png_infop info_ptr, int intent));
2342#endif
2343
2344#if defined(PNG_iCCP_SUPPORTED)
2345extern PNG_EXPORT(png_uint_32,png_get_iCCP) PNGARG((png_structp png_ptr,
2346 png_infop info_ptr, png_charpp name, int *compression_type,
2347 png_charpp profile, png_uint_32 *proflen));
2348 /* Note to maintainer: profile should be png_bytepp */
2349#endif
2350
2351#if defined(PNG_iCCP_SUPPORTED)
2352extern PNG_EXPORT(void,png_set_iCCP) PNGARG((png_structp png_ptr,
2353 png_infop info_ptr, png_charp name, int compression_type,
2354 png_charp profile, png_uint_32 proflen));
2355 /* Note to maintainer: profile should be png_bytep */
2356#endif
2357
2358#if defined(PNG_sPLT_SUPPORTED)
2359extern PNG_EXPORT(png_uint_32,png_get_sPLT) PNGARG((png_structp png_ptr,
2360 png_infop info_ptr, png_sPLT_tpp entries));
2361#endif
2362
2363#if defined(PNG_sPLT_SUPPORTED)
2364extern PNG_EXPORT(void,png_set_sPLT) PNGARG((png_structp png_ptr,
2365 png_infop info_ptr, png_sPLT_tp entries, int nentries));
2366#endif
2367
2368#if defined(PNG_TEXT_SUPPORTED)
2369/* png_get_text also returns the number of text chunks in *num_text */
2370extern PNG_EXPORT(png_uint_32,png_get_text) PNGARG((png_structp png_ptr,
2371 png_infop info_ptr, png_textp *text_ptr, int *num_text));
2372#endif
2373
2374/*
2375 * Note while png_set_text() will accept a structure whose text,
2376 * language, and translated keywords are NULL pointers, the structure
2377 * returned by png_get_text will always contain regular
2378 * zero-terminated C strings. They might be empty strings but
2379 * they will never be NULL pointers.
2380 */
2381
2382#if defined(PNG_TEXT_SUPPORTED)
2383extern PNG_EXPORT(void,png_set_text) PNGARG((png_structp png_ptr,
2384 png_infop info_ptr, png_textp text_ptr, int num_text));
2385#endif
2386
2387#if defined(PNG_tIME_SUPPORTED)
2388extern PNG_EXPORT(png_uint_32,png_get_tIME) PNGARG((png_structp png_ptr,
2389 png_infop info_ptr, png_timep *mod_time));
2390#endif
2391
2392#if defined(PNG_tIME_SUPPORTED)
2393extern PNG_EXPORT(void,png_set_tIME) PNGARG((png_structp png_ptr,
2394 png_infop info_ptr, png_timep mod_time));
2395#endif
2396
2397#if defined(PNG_tRNS_SUPPORTED)
2398extern PNG_EXPORT(png_uint_32,png_get_tRNS) PNGARG((png_structp png_ptr,
2399 png_infop info_ptr, png_bytep *trans, int *num_trans,
2400 png_color_16p *trans_values));
2401#endif
2402
2403#if defined(PNG_tRNS_SUPPORTED)
2404extern PNG_EXPORT(void,png_set_tRNS) PNGARG((png_structp png_ptr,
2405 png_infop info_ptr, png_bytep trans, int num_trans,
2406 png_color_16p trans_values));
2407#endif
2408
2409#if defined(PNG_tRNS_SUPPORTED)
2410#endif
2411
2412#if defined(PNG_sCAL_SUPPORTED)
2413#ifdef PNG_FLOATING_POINT_SUPPORTED
2414extern PNG_EXPORT(png_uint_32,png_get_sCAL) PNGARG((png_structp png_ptr,
2415 png_infop info_ptr, int *unit, double *width, double *height));
2416#else
2417#ifdef PNG_FIXED_POINT_SUPPORTED
2418extern PNG_EXPORT(png_uint_32,png_get_sCAL_s) PNGARG((png_structp png_ptr,
2419 png_infop info_ptr, int *unit, png_charpp swidth, png_charpp sheight));
2420#endif
2421#endif
2422#endif /* PNG_sCAL_SUPPORTED */
2423
2424#if defined(PNG_sCAL_SUPPORTED)
2425#ifdef PNG_FLOATING_POINT_SUPPORTED
2426extern PNG_EXPORT(void,png_set_sCAL) PNGARG((png_structp png_ptr,
2427 png_infop info_ptr, int unit, double width, double height));
2428#else
2429#ifdef PNG_FIXED_POINT_SUPPORTED
2430extern PNG_EXPORT(void,png_set_sCAL_s) PNGARG((png_structp png_ptr,
2431 png_infop info_ptr, int unit, png_charp swidth, png_charp sheight));
2432#endif
2433#endif
2434#endif /* PNG_sCAL_SUPPORTED || PNG_WRITE_sCAL_SUPPORTED */
2435
2436#if defined(PNG_UNKNOWN_CHUNKS_SUPPORTED)
2437/* provide a list of chunks and how they are to be handled, if the built-in
2438 handling or default unknown chunk handling is not desired. Any chunks not
2439 listed will be handled in the default manner. The IHDR and IEND chunks
2440 must not be listed.
2441 keep = 0: follow default behaviour
2442 = 1: do not keep
2443 = 2: keep only if safe-to-copy
2444 = 3: keep even if unsafe-to-copy
2445*/
2446extern PNG_EXPORT(void, png_set_keep_unknown_chunks) PNGARG((png_structp
2447 png_ptr, int keep, png_bytep chunk_list, int num_chunks));
2448extern PNG_EXPORT(void, png_set_unknown_chunks) PNGARG((png_structp png_ptr,
2449 png_infop info_ptr, png_unknown_chunkp unknowns, int num_unknowns));
2450extern PNG_EXPORT(void, png_set_unknown_chunk_location)
2451 PNGARG((png_structp png_ptr, png_infop info_ptr, int chunk, int location));
2452extern PNG_EXPORT(png_uint_32,png_get_unknown_chunks) PNGARG((png_structp
2453 png_ptr, png_infop info_ptr, png_unknown_chunkpp entries));
2454#endif
2455#ifdef PNG_HANDLE_AS_UNKNOWN_SUPPORTED
2456PNG_EXPORT(int,png_handle_as_unknown) PNGARG((png_structp png_ptr, png_bytep
2457 chunk_name));
2458#endif
2459
2460/* Png_free_data() will turn off the "valid" flag for anything it frees.
2461 If you need to turn it off for a chunk that your application has freed,
2462 you can use png_set_invalid(png_ptr, info_ptr, PNG_INFO_CHNK); */
2463extern PNG_EXPORT(void, png_set_invalid) PNGARG((png_structp png_ptr,
2464 png_infop info_ptr, int mask));
2465
2466#if defined(PNG_INFO_IMAGE_SUPPORTED)
2467/* The "params" pointer is currently not used and is for future expansion. */
2468extern PNG_EXPORT(void, png_read_png) PNGARG((png_structp png_ptr,
2469 png_infop info_ptr,
2470 int transforms,
2471 png_voidp params));
2472extern PNG_EXPORT(void, png_write_png) PNGARG((png_structp png_ptr,
2473 png_infop info_ptr,
2474 int transforms,
2475 png_voidp params));
2476#endif
2477
2478/* Define PNG_DEBUG at compile time for debugging information. Higher
2479 * numbers for PNG_DEBUG mean more debugging information. This has
2480 * only been added since version 0.95 so it is not implemented throughout
2481 * libpng yet, but more support will be added as needed.
2482 */
2483#ifdef PNG_DEBUG
2484#if (PNG_DEBUG > 0)
2485#if !defined(PNG_DEBUG_FILE) && defined(_MSC_VER)
2486#include <crtdbg.h>
2487#if (PNG_DEBUG > 1)
2488#define png_debug(l,m) _RPT0(_CRT_WARN,m)
2489#define png_debug1(l,m,p1) _RPT1(_CRT_WARN,m,p1)
2490#define png_debug2(l,m,p1,p2) _RPT2(_CRT_WARN,m,p1,p2)
2491#endif
2492#else /* PNG_DEBUG_FILE || !_MSC_VER */
2493#ifndef PNG_DEBUG_FILE
2494#define PNG_DEBUG_FILE stderr
2495#endif /* PNG_DEBUG_FILE */
2496#if (PNG_DEBUG > 1)
2497#define png_debug(l,m) \
2498{ \
2499 int num_tabs=l; \
2500 fprintf(PNG_DEBUG_FILE,"%s"m,(num_tabs==1 ? "\t" : \
2501 (num_tabs==2 ? "\t\t":(num_tabs>2 ? "\t\t\t":"")))); \
2502}
2503#define png_debug1(l,m,p1) \
2504{ \
2505 int num_tabs=l; \
2506 fprintf(PNG_DEBUG_FILE,"%s"m,(num_tabs==1 ? "\t" : \
2507 (num_tabs==2 ? "\t\t":(num_tabs>2 ? "\t\t\t":""))),p1); \
2508}
2509#define png_debug2(l,m,p1,p2) \
2510{ \
2511 int num_tabs=l; \
2512 fprintf(PNG_DEBUG_FILE,"%s"m,(num_tabs==1 ? "\t" : \
2513 (num_tabs==2 ? "\t\t":(num_tabs>2 ? "\t\t\t":""))),p1,p2); \
2514}
2515#endif /* (PNG_DEBUG > 1) */
2516#endif /* _MSC_VER */
2517#endif /* (PNG_DEBUG > 0) */
2518#endif /* PNG_DEBUG */
2519#ifndef png_debug
2520#define png_debug(l, m)
2521#endif
2522#ifndef png_debug1
2523#define png_debug1(l, m, p1)
2524#endif
2525#ifndef png_debug2
2526#define png_debug2(l, m, p1, p2)
2527#endif
2528
2529extern PNG_EXPORT(png_charp,png_get_copyright) PNGARG((png_structp png_ptr));
2530extern PNG_EXPORT(png_charp,png_get_header_ver) PNGARG((png_structp png_ptr));
2531extern PNG_EXPORT(png_charp,png_get_header_version) PNGARG((png_structp png_ptr));
2532extern PNG_EXPORT(png_charp,png_get_libpng_ver) PNGARG((png_structp png_ptr));
2533
2534#ifdef PNG_MNG_FEATURES_SUPPORTED
2535extern PNG_EXPORT(png_uint_32,png_permit_mng_features) PNGARG((png_structp
2536 png_ptr, png_uint_32 mng_features_permitted));
2537#endif
2538
2539/* For use in png_set_keep_unknown, added to version 1.2.6 */
2540#define PNG_HANDLE_CHUNK_AS_DEFAULT 0
2541#define PNG_HANDLE_CHUNK_NEVER 1
2542#define PNG_HANDLE_CHUNK_IF_SAFE 2
2543#define PNG_HANDLE_CHUNK_ALWAYS 3
2544
2545/* Added to version 1.2.0 */
2546#if defined(PNG_ASSEMBLER_CODE_SUPPORTED)
2547#if defined(PNG_MMX_CODE_SUPPORTED)
2548#define PNG_ASM_FLAG_MMX_SUPPORT_COMPILED 0x01 /* not user-settable */
2549#define PNG_ASM_FLAG_MMX_SUPPORT_IN_CPU 0x02 /* not user-settable */
2550#define PNG_ASM_FLAG_MMX_READ_COMBINE_ROW 0x04
2551#define PNG_ASM_FLAG_MMX_READ_INTERLACE 0x08
2552#define PNG_ASM_FLAG_MMX_READ_FILTER_SUB 0x10
2553#define PNG_ASM_FLAG_MMX_READ_FILTER_UP 0x20
2554#define PNG_ASM_FLAG_MMX_READ_FILTER_AVG 0x40
2555#define PNG_ASM_FLAG_MMX_READ_FILTER_PAETH 0x80
2556#define PNG_ASM_FLAGS_INITIALIZED 0x80000000 /* not user-settable */
2557
2558#define PNG_MMX_READ_FLAGS ( PNG_ASM_FLAG_MMX_READ_COMBINE_ROW \
2559 | PNG_ASM_FLAG_MMX_READ_INTERLACE \
2560 | PNG_ASM_FLAG_MMX_READ_FILTER_SUB \
2561 | PNG_ASM_FLAG_MMX_READ_FILTER_UP \
2562 | PNG_ASM_FLAG_MMX_READ_FILTER_AVG \
2563 | PNG_ASM_FLAG_MMX_READ_FILTER_PAETH )
2564#define PNG_MMX_WRITE_FLAGS ( 0 )
2565
2566#define PNG_MMX_FLAGS ( PNG_ASM_FLAG_MMX_SUPPORT_COMPILED \
2567 | PNG_ASM_FLAG_MMX_SUPPORT_IN_CPU \
2568 | PNG_MMX_READ_FLAGS \
2569 | PNG_MMX_WRITE_FLAGS )
2570
2571#define PNG_SELECT_READ 1
2572#define PNG_SELECT_WRITE 2
2573#endif /* PNG_MMX_CODE_SUPPORTED */
2574
2575#if !defined(PNG_1_0_X)
2576/* pngget.c */
2577extern PNG_EXPORT(png_uint_32,png_get_mmx_flagmask)
2578 PNGARG((int flag_select, int *compilerID));
2579
2580/* pngget.c */
2581extern PNG_EXPORT(png_uint_32,png_get_asm_flagmask)
2582 PNGARG((int flag_select));
2583
2584/* pngget.c */
2585extern PNG_EXPORT(png_uint_32,png_get_asm_flags)
2586 PNGARG((png_structp png_ptr));
2587
2588/* pngget.c */
2589extern PNG_EXPORT(png_byte,png_get_mmx_bitdepth_threshold)
2590 PNGARG((png_structp png_ptr));
2591
2592/* pngget.c */
2593extern PNG_EXPORT(png_uint_32,png_get_mmx_rowbytes_threshold)
2594 PNGARG((png_structp png_ptr));
2595
2596/* pngset.c */
2597extern PNG_EXPORT(void,png_set_asm_flags)
2598 PNGARG((png_structp png_ptr, png_uint_32 asm_flags));
2599
2600/* pngset.c */
2601extern PNG_EXPORT(void,png_set_mmx_thresholds)
2602 PNGARG((png_structp png_ptr, png_byte mmx_bitdepth_threshold,
2603 png_uint_32 mmx_rowbytes_threshold));
2604
2605#endif /* PNG_1_0_X */
2606
2607#if !defined(PNG_1_0_X)
2608/* png.c, pnggccrd.c, or pngvcrd.c */
2609extern PNG_EXPORT(int,png_mmx_support) PNGARG((void));
2610#endif /* PNG_ASSEMBLER_CODE_SUPPORTED */
2611
2612/* Strip the prepended error numbers ("#nnn ") from error and warning
2613 * messages before passing them to the error or warning handler. */
2614#ifdef PNG_ERROR_NUMBERS_SUPPORTED
2615extern PNG_EXPORT(void,png_set_strip_error_numbers) PNGARG((png_structp
2616 png_ptr, png_uint_32 strip_mode));
2617#endif
2618
2619#endif /* PNG_1_0_X */
2620
2621/* Added at libpng-1.2.6 */
2622#ifdef PNG_SET_USER_LIMITS_SUPPORTED
2623extern PNG_EXPORT(void,png_set_user_limits) PNGARG((png_structp
2624 png_ptr, png_uint_32 user_width_max, png_uint_32 user_height_max));
2625extern PNG_EXPORT(png_uint_32,png_get_user_width_max) PNGARG((png_structp
2626 png_ptr));
2627extern PNG_EXPORT(png_uint_32,png_get_user_height_max) PNGARG((png_structp
2628 png_ptr));
2629#endif
2630
2631/* Maintainer: Put new public prototypes here ^, in libpng.3, and project defs */
2632
2633#ifdef PNG_READ_COMPOSITE_NODIV_SUPPORTED
2634/* With these routines we avoid an integer divide, which will be slower on
2635 * most machines. However, it does take more operations than the corresponding
2636 * divide method, so it may be slower on a few RISC systems. There are two
2637 * shifts (by 8 or 16 bits) and an addition, versus a single integer divide.
2638 *
2639 * Note that the rounding factors are NOT supposed to be the same! 128 and
2640 * 32768 are correct for the NODIV code; 127 and 32767 are correct for the
2641 * standard method.
2642 *
2643 * [Optimized code by Greg Roelofs and Mark Adler...blame us for bugs. :-) ]
2644 */
2645
2646 /* fg and bg should be in `gamma 1.0' space; alpha is the opacity */
2647
2648# define png_composite(composite, fg, alpha, bg) \
2649 { png_uint_16 temp = (png_uint_16)((png_uint_16)(fg) * (png_uint_16)(alpha) \
2650 + (png_uint_16)(bg)*(png_uint_16)(255 - \
2651 (png_uint_16)(alpha)) + (png_uint_16)128); \
2652 (composite) = (png_byte)((temp + (temp >> 8)) >> 8); }
2653
2654# define png_composite_16(composite, fg, alpha, bg) \
2655 { png_uint_32 temp = (png_uint_32)((png_uint_32)(fg) * (png_uint_32)(alpha) \
2656 + (png_uint_32)(bg)*(png_uint_32)(65535L - \
2657 (png_uint_32)(alpha)) + (png_uint_32)32768L); \
2658 (composite) = (png_uint_16)((temp + (temp >> 16)) >> 16); }
2659
2660#else /* standard method using integer division */
2661
2662# define png_composite(composite, fg, alpha, bg) \
2663 (composite) = (png_byte)(((png_uint_16)(fg) * (png_uint_16)(alpha) + \
2664 (png_uint_16)(bg) * (png_uint_16)(255 - (png_uint_16)(alpha)) + \
2665 (png_uint_16)127) / 255)
2666
2667# define png_composite_16(composite, fg, alpha, bg) \
2668 (composite) = (png_uint_16)(((png_uint_32)(fg) * (png_uint_32)(alpha) + \
2669 (png_uint_32)(bg)*(png_uint_32)(65535L - (png_uint_32)(alpha)) + \
2670 (png_uint_32)32767) / (png_uint_32)65535L)
2671
2672#endif /* PNG_READ_COMPOSITE_NODIV_SUPPORTED */
2673
2674/* Inline macros to do direct reads of bytes from the input buffer. These
2675 * require that you are using an architecture that uses PNG byte ordering
2676 * (MSB first) and supports unaligned data storage. I think that PowerPC
2677 * in big-endian mode and 680x0 are the only ones that will support this.
2678 * The x86 line of processors definitely do not. The png_get_int_32()
2679 * routine also assumes we are using two's complement format for negative
2680 * values, which is almost certainly true.
2681 */
2682#if defined(PNG_READ_BIG_ENDIAN_SUPPORTED)
2683# define png_get_uint_32(buf) ( *((png_uint_32p) (buf)))
2684# define png_get_uint_16(buf) ( *((png_uint_16p) (buf)))
2685# define png_get_int_32(buf) ( *((png_int_32p) (buf)))
2686#else
2687extern PNG_EXPORT(png_uint_32,png_get_uint_32) PNGARG((png_bytep buf));
2688extern PNG_EXPORT(png_uint_16,png_get_uint_16) PNGARG((png_bytep buf));
2689extern PNG_EXPORT(png_int_32,png_get_int_32) PNGARG((png_bytep buf));
2690#endif /* !PNG_READ_BIG_ENDIAN_SUPPORTED */
2691extern PNG_EXPORT(png_uint_32,png_get_uint_31)
2692 PNGARG((png_structp png_ptr, png_bytep buf));
2693/* No png_get_int_16 -- may be added if there's a real need for it. */
2694
2695/* Place a 32-bit number into a buffer in PNG byte order (big-endian).
2696 */
2697extern PNG_EXPORT(void,png_save_uint_32)
2698 PNGARG((png_bytep buf, png_uint_32 i));
2699extern PNG_EXPORT(void,png_save_int_32)
2700 PNGARG((png_bytep buf, png_int_32 i));
2701
2702/* Place a 16-bit number into a buffer in PNG byte order.
2703 * The parameter is declared unsigned int, not png_uint_16,
2704 * just to avoid potential problems on pre-ANSI C compilers.
2705 */
2706extern PNG_EXPORT(void,png_save_uint_16)
2707 PNGARG((png_bytep buf, unsigned int i));
2708/* No png_save_int_16 -- may be added if there's a real need for it. */
2709
2710/* ************************************************************************* */
2711
2712/* These next functions are used internally in the code. They generally
2713 * shouldn't be used unless you are writing code to add or replace some
2714 * functionality in libpng. More information about most functions can
2715 * be found in the files where the functions are located.
2716 */
2717
2718
2719/* Various modes of operation, that are visible to applications because
2720 * they are used for unknown chunk location.
2721 */
2722#define PNG_HAVE_IHDR 0x01
2723#define PNG_HAVE_PLTE 0x02
2724#define PNG_HAVE_IDAT 0x04
2725#define PNG_AFTER_IDAT 0x08 /* Have complete zlib datastream */
2726#define PNG_HAVE_IEND 0x10
2727
2728#if defined(PNG_INTERNAL)
2729
2730/* More modes of operation. Note that after an init, mode is set to
2731 * zero automatically when the structure is created.
2732 */
2733#define PNG_HAVE_gAMA 0x20
2734#define PNG_HAVE_cHRM 0x40
2735#define PNG_HAVE_sRGB 0x80
2736#define PNG_HAVE_CHUNK_HEADER 0x100
2737#define PNG_WROTE_tIME 0x200
2738#define PNG_WROTE_INFO_BEFORE_PLTE 0x400
2739#define PNG_BACKGROUND_IS_GRAY 0x800
2740#define PNG_HAVE_PNG_SIGNATURE 0x1000
2741#define PNG_HAVE_CHUNK_AFTER_IDAT 0x2000 /* Have another chunk after IDAT */
2742
2743/* flags for the transformations the PNG library does on the image data */
2744#define PNG_BGR 0x0001
2745#define PNG_INTERLACE 0x0002
2746#define PNG_PACK 0x0004
2747#define PNG_SHIFT 0x0008
2748#define PNG_SWAP_BYTES 0x0010
2749#define PNG_INVERT_MONO 0x0020
2750#define PNG_DITHER 0x0040
2751#define PNG_BACKGROUND 0x0080
2752#define PNG_BACKGROUND_EXPAND 0x0100
2753 /* 0x0200 unused */
2754#define PNG_16_TO_8 0x0400
2755#define PNG_RGBA 0x0800
2756#define PNG_EXPAND 0x1000
2757#define PNG_GAMMA 0x2000
2758#define PNG_GRAY_TO_RGB 0x4000
2759#define PNG_FILLER 0x8000L
2760#define PNG_PACKSWAP 0x10000L
2761#define PNG_SWAP_ALPHA 0x20000L
2762#define PNG_STRIP_ALPHA 0x40000L
2763#define PNG_INVERT_ALPHA 0x80000L
2764#define PNG_USER_TRANSFORM 0x100000L
2765#define PNG_RGB_TO_GRAY_ERR 0x200000L
2766#define PNG_RGB_TO_GRAY_WARN 0x400000L
2767#define PNG_RGB_TO_GRAY 0x600000L /* two bits, RGB_TO_GRAY_ERR|WARN */
2768 /* 0x800000L Unused */
2769#define PNG_ADD_ALPHA 0x1000000L /* Added to libpng-1.2.7 */
2770#define PNG_EXPAND_tRNS 0x2000000L /* Added to libpng-1.2.9 */
2771 /* 0x4000000L unused */
2772 /* 0x8000000L unused */
2773 /* 0x10000000L unused */
2774 /* 0x20000000L unused */
2775 /* 0x40000000L unused */
2776
2777/* flags for png_create_struct */
2778#define PNG_STRUCT_PNG 0x0001
2779#define PNG_STRUCT_INFO 0x0002
2780
2781/* Scaling factor for filter heuristic weighting calculations */
2782#define PNG_WEIGHT_SHIFT 8
2783#define PNG_WEIGHT_FACTOR (1<<(PNG_WEIGHT_SHIFT))
2784#define PNG_COST_SHIFT 3
2785#define PNG_COST_FACTOR (1<<(PNG_COST_SHIFT))
2786
2787/* flags for the png_ptr->flags rather than declaring a byte for each one */
2788#define PNG_FLAG_ZLIB_CUSTOM_STRATEGY 0x0001
2789#define PNG_FLAG_ZLIB_CUSTOM_LEVEL 0x0002
2790#define PNG_FLAG_ZLIB_CUSTOM_MEM_LEVEL 0x0004
2791#define PNG_FLAG_ZLIB_CUSTOM_WINDOW_BITS 0x0008
2792#define PNG_FLAG_ZLIB_CUSTOM_METHOD 0x0010
2793#define PNG_FLAG_ZLIB_FINISHED 0x0020
2794#define PNG_FLAG_ROW_INIT 0x0040
2795#define PNG_FLAG_FILLER_AFTER 0x0080
2796#define PNG_FLAG_CRC_ANCILLARY_USE 0x0100
2797#define PNG_FLAG_CRC_ANCILLARY_NOWARN 0x0200
2798#define PNG_FLAG_CRC_CRITICAL_USE 0x0400
2799#define PNG_FLAG_CRC_CRITICAL_IGNORE 0x0800
2800#define PNG_FLAG_FREE_PLTE 0x1000
2801#define PNG_FLAG_FREE_TRNS 0x2000
2802#define PNG_FLAG_FREE_HIST 0x4000
2803#define PNG_FLAG_KEEP_UNKNOWN_CHUNKS 0x8000L
2804#define PNG_FLAG_KEEP_UNSAFE_CHUNKS 0x10000L
2805#define PNG_FLAG_LIBRARY_MISMATCH 0x20000L
2806#define PNG_FLAG_STRIP_ERROR_NUMBERS 0x40000L
2807#define PNG_FLAG_STRIP_ERROR_TEXT 0x80000L
2808#define PNG_FLAG_MALLOC_NULL_MEM_OK 0x100000L
2809#define PNG_FLAG_ADD_ALPHA 0x200000L /* Added to libpng-1.2.8 */
2810#define PNG_FLAG_STRIP_ALPHA 0x400000L /* Added to libpng-1.2.8 */
2811 /* 0x800000L unused */
2812 /* 0x1000000L unused */
2813 /* 0x2000000L unused */
2814 /* 0x4000000L unused */
2815 /* 0x8000000L unused */
2816 /* 0x10000000L unused */
2817 /* 0x20000000L unused */
2818 /* 0x40000000L unused */
2819
2820#define PNG_FLAG_CRC_ANCILLARY_MASK (PNG_FLAG_CRC_ANCILLARY_USE | \
2821 PNG_FLAG_CRC_ANCILLARY_NOWARN)
2822
2823#define PNG_FLAG_CRC_CRITICAL_MASK (PNG_FLAG_CRC_CRITICAL_USE | \
2824 PNG_FLAG_CRC_CRITICAL_IGNORE)
2825
2826#define PNG_FLAG_CRC_MASK (PNG_FLAG_CRC_ANCILLARY_MASK | \
2827 PNG_FLAG_CRC_CRITICAL_MASK)
2828
2829/* save typing and make code easier to understand */
2830
2831#define PNG_COLOR_DIST(c1, c2) (abs((int)((c1).red) - (int)((c2).red)) + \
2832 abs((int)((c1).green) - (int)((c2).green)) + \
2833 abs((int)((c1).blue) - (int)((c2).blue)))
2834
2835/* Added to libpng-1.2.6 JB */
2836#define PNG_ROWBYTES(pixel_bits, width) \
2837 ((pixel_bits) >= 8 ? \
2838 ((width) * (((png_uint_32)(pixel_bits)) >> 3)) : \
2839 (( ((width) * ((png_uint_32)(pixel_bits))) + 7) >> 3) )
2840
2841/* PNG_OUT_OF_RANGE returns true if value is outside the range
2842 ideal-delta..ideal+delta. Each argument is evaluated twice.
2843 "ideal" and "delta" should be constants, normally simple
2844 integers, "value" a variable. Added to libpng-1.2.6 JB */
2845#define PNG_OUT_OF_RANGE(value, ideal, delta) \
2846 ( (value) < (ideal)-(delta) || (value) > (ideal)+(delta) )
2847
2848/* variables declared in png.c - only it needs to define PNG_NO_EXTERN */
2849#if !defined(PNG_NO_EXTERN) || defined(PNG_ALWAYS_EXTERN)
2850/* place to hold the signature string for a PNG file. */
2851#ifdef PNG_USE_GLOBAL_ARRAYS
2852 PNG_EXPORT_VAR (PNG_CONST png_byte FARDATA) png_sig[8];
2853#else
2854#endif
2855#endif /* PNG_NO_EXTERN */
2856
2857/* Constant strings for known chunk types. If you need to add a chunk,
2858 * define the name here, and add an invocation of the macro in png.c and
2859 * wherever it's needed.
2860 */
2861#define PNG_IHDR png_byte png_IHDR[5] = { 73, 72, 68, 82, '\0'}
2862#define PNG_IDAT png_byte png_IDAT[5] = { 73, 68, 65, 84, '\0'}
2863#define PNG_IEND png_byte png_IEND[5] = { 73, 69, 78, 68, '\0'}
2864#define PNG_PLTE png_byte png_PLTE[5] = { 80, 76, 84, 69, '\0'}
2865#define PNG_bKGD png_byte png_bKGD[5] = { 98, 75, 71, 68, '\0'}
2866#define PNG_cHRM png_byte png_cHRM[5] = { 99, 72, 82, 77, '\0'}
2867#define PNG_gAMA png_byte png_gAMA[5] = {103, 65, 77, 65, '\0'}
2868#define PNG_hIST png_byte png_hIST[5] = {104, 73, 83, 84, '\0'}
2869#define PNG_iCCP png_byte png_iCCP[5] = {105, 67, 67, 80, '\0'}
2870#define PNG_iTXt png_byte png_iTXt[5] = {105, 84, 88, 116, '\0'}
2871#define PNG_oFFs png_byte png_oFFs[5] = {111, 70, 70, 115, '\0'}
2872#define PNG_pCAL png_byte png_pCAL[5] = {112, 67, 65, 76, '\0'}
2873#define PNG_sCAL png_byte png_sCAL[5] = {115, 67, 65, 76, '\0'}
2874#define PNG_pHYs png_byte png_pHYs[5] = {112, 72, 89, 115, '\0'}
2875#define PNG_sBIT png_byte png_sBIT[5] = {115, 66, 73, 84, '\0'}
2876#define PNG_sPLT png_byte png_sPLT[5] = {115, 80, 76, 84, '\0'}
2877#define PNG_sRGB png_byte png_sRGB[5] = {115, 82, 71, 66, '\0'}
2878#define PNG_tEXt png_byte png_tEXt[5] = {116, 69, 88, 116, '\0'}
2879#define PNG_tIME png_byte png_tIME[5] = {116, 73, 77, 69, '\0'}
2880#define PNG_tRNS png_byte png_tRNS[5] = {116, 82, 78, 83, '\0'}
2881#define PNG_zTXt png_byte png_zTXt[5] = {122, 84, 88, 116, '\0'}
2882
2883#ifdef PNG_USE_GLOBAL_ARRAYS
2884PNG_EXPORT_VAR (png_byte FARDATA) png_IHDR[5];
2885PNG_EXPORT_VAR (png_byte FARDATA) png_IDAT[5];
2886PNG_EXPORT_VAR (png_byte FARDATA) png_IEND[5];
2887PNG_EXPORT_VAR (png_byte FARDATA) png_PLTE[5];
2888PNG_EXPORT_VAR (png_byte FARDATA) png_bKGD[5];
2889PNG_EXPORT_VAR (png_byte FARDATA) png_cHRM[5];
2890PNG_EXPORT_VAR (png_byte FARDATA) png_gAMA[5];
2891PNG_EXPORT_VAR (png_byte FARDATA) png_hIST[5];
2892PNG_EXPORT_VAR (png_byte FARDATA) png_iCCP[5];
2893PNG_EXPORT_VAR (png_byte FARDATA) png_iTXt[5];
2894PNG_EXPORT_VAR (png_byte FARDATA) png_oFFs[5];
2895PNG_EXPORT_VAR (png_byte FARDATA) png_pCAL[5];
2896PNG_EXPORT_VAR (png_byte FARDATA) png_sCAL[5];
2897PNG_EXPORT_VAR (png_byte FARDATA) png_pHYs[5];
2898PNG_EXPORT_VAR (png_byte FARDATA) png_sBIT[5];
2899PNG_EXPORT_VAR (png_byte FARDATA) png_sPLT[5];
2900PNG_EXPORT_VAR (png_byte FARDATA) png_sRGB[5];
2901PNG_EXPORT_VAR (png_byte FARDATA) png_tEXt[5];
2902PNG_EXPORT_VAR (png_byte FARDATA) png_tIME[5];
2903PNG_EXPORT_VAR (png_byte FARDATA) png_tRNS[5];
2904PNG_EXPORT_VAR (png_byte FARDATA) png_zTXt[5];
2905#endif /* PNG_USE_GLOBAL_ARRAYS */
2906
2907#if defined(PNG_1_0_X) || defined (PNG_1_2_X)
2908/* Initialize png_ptr struct for reading, and allocate any other memory.
2909 * (old interface - DEPRECATED - use png_create_read_struct instead).
2910 */
2911extern PNG_EXPORT(void,png_read_init) PNGARG((png_structp png_ptr));
2912#undef png_read_init
2913#define png_read_init(png_ptr) png_read_init_3(&png_ptr, \
2914 PNG_LIBPNG_VER_STRING, png_sizeof(png_struct));
2915#endif
2916
2917extern PNG_EXPORT(void,png_read_init_3) PNGARG((png_structpp ptr_ptr,
2918 png_const_charp user_png_ver, png_size_t png_struct_size));
2919#if defined(PNG_1_0_X) || defined (PNG_1_2_X)
2920extern PNG_EXPORT(void,png_read_init_2) PNGARG((png_structp png_ptr,
2921 png_const_charp user_png_ver, png_size_t png_struct_size, png_size_t
2922 png_info_size));
2923#endif
2924
2925#if defined(PNG_1_0_X) || defined (PNG_1_2_X)
2926/* Initialize png_ptr struct for writing, and allocate any other memory.
2927 * (old interface - DEPRECATED - use png_create_write_struct instead).
2928 */
2929extern PNG_EXPORT(void,png_write_init) PNGARG((png_structp png_ptr));
2930#undef png_write_init
2931#define png_write_init(png_ptr) png_write_init_3(&png_ptr, \
2932 PNG_LIBPNG_VER_STRING, png_sizeof(png_struct));
2933#endif
2934
2935extern PNG_EXPORT(void,png_write_init_3) PNGARG((png_structpp ptr_ptr,
2936 png_const_charp user_png_ver, png_size_t png_struct_size));
2937extern PNG_EXPORT(void,png_write_init_2) PNGARG((png_structp png_ptr,
2938 png_const_charp user_png_ver, png_size_t png_struct_size, png_size_t
2939 png_info_size));
2940
2941/* Allocate memory for an internal libpng struct */
2942PNG_EXTERN png_voidp png_create_struct PNGARG((int type));
2943
2944/* Free memory from internal libpng struct */
2945PNG_EXTERN void png_destroy_struct PNGARG((png_voidp struct_ptr));
2946
2947PNG_EXTERN png_voidp png_create_struct_2 PNGARG((int type, png_malloc_ptr
2948 malloc_fn, png_voidp mem_ptr));
2949PNG_EXTERN void png_destroy_struct_2 PNGARG((png_voidp struct_ptr,
2950 png_free_ptr free_fn, png_voidp mem_ptr));
2951
2952/* Free any memory that info_ptr points to and reset struct. */
2953PNG_EXTERN void png_info_destroy PNGARG((png_structp png_ptr,
2954 png_infop info_ptr));
2955
2956#ifndef PNG_1_0_X
2957/* Function to allocate memory for zlib. */
2958PNG_EXTERN voidpf png_zalloc PNGARG((voidpf png_ptr, uInt items, uInt size));
2959
2960/* Function to free memory for zlib */
2961PNG_EXTERN void png_zfree PNGARG((voidpf png_ptr, voidpf ptr));
2962
2963#ifdef PNG_SIZE_T
2964/* Function to convert a sizeof an item to png_sizeof item */
2965 PNG_EXTERN png_size_t PNGAPI png_convert_size PNGARG((size_t size));
2966#endif
2967
2968/* Next four functions are used internally as callbacks. PNGAPI is required
2969 * but not PNG_EXPORT. PNGAPI added at libpng version 1.2.3. */
2970
2971PNG_EXTERN void PNGAPI png_default_read_data PNGARG((png_structp png_ptr,
2972 png_bytep data, png_size_t length));
2973
2974#ifdef PNG_PROGRESSIVE_READ_SUPPORTED
2975PNG_EXTERN void PNGAPI png_push_fill_buffer PNGARG((png_structp png_ptr,
2976 png_bytep buffer, png_size_t length));
2977#endif
2978
2979PNG_EXTERN void PNGAPI png_default_write_data PNGARG((png_structp png_ptr,
2980 png_bytep data, png_size_t length));
2981
2982#if defined(PNG_WRITE_FLUSH_SUPPORTED)
2983#if !defined(PNG_NO_STDIO)
2984PNG_EXTERN void PNGAPI png_default_flush PNGARG((png_structp png_ptr));
2985#endif
2986#endif
2987#else /* PNG_1_0_X */
2988#ifdef PNG_PROGRESSIVE_READ_SUPPORTED
2989PNG_EXTERN void png_push_fill_buffer PNGARG((png_structp png_ptr,
2990 png_bytep buffer, png_size_t length));
2991#endif
2992#endif /* PNG_1_0_X */
2993
2994/* Reset the CRC variable */
2995PNG_EXTERN void png_reset_crc PNGARG((png_structp png_ptr));
2996
2997/* Write the "data" buffer to whatever output you are using. */
2998PNG_EXTERN void png_write_data PNGARG((png_structp png_ptr, png_bytep data,
2999 png_size_t length));
3000
3001/* Read data from whatever input you are using into the "data" buffer */
3002PNG_EXTERN void png_read_data PNGARG((png_structp png_ptr, png_bytep data,
3003 png_size_t length));
3004
3005/* Read bytes into buf, and update png_ptr->crc */
3006PNG_EXTERN void png_crc_read PNGARG((png_structp png_ptr, png_bytep buf,
3007 png_size_t length));
3008
3009/* Decompress data in a chunk that uses compression */
3010#if defined(PNG_zTXt_SUPPORTED) || defined(PNG_iTXt_SUPPORTED) || \
3011 defined(PNG_iCCP_SUPPORTED) || defined(PNG_sPLT_SUPPORTED)
3012PNG_EXTERN png_charp png_decompress_chunk PNGARG((png_structp png_ptr,
3013 int comp_type, png_charp chunkdata, png_size_t chunklength,
3014 png_size_t prefix_length, png_size_t *data_length));
3015#endif
3016
3017/* Read "skip" bytes, read the file crc, and (optionally) verify png_ptr->crc */
3018PNG_EXTERN int png_crc_finish PNGARG((png_structp png_ptr, png_uint_32 skip));
3019
3020/* Read the CRC from the file and compare it to the libpng calculated CRC */
3021PNG_EXTERN int png_crc_error PNGARG((png_structp png_ptr));
3022
3023/* Calculate the CRC over a section of data. Note that we are only
3024 * passing a maximum of 64K on systems that have this as a memory limit,
3025 * since this is the maximum buffer size we can specify.
3026 */
3027PNG_EXTERN void png_calculate_crc PNGARG((png_structp png_ptr, png_bytep ptr,
3028 png_size_t length));
3029
3030#if defined(PNG_WRITE_FLUSH_SUPPORTED)
3031PNG_EXTERN void png_flush PNGARG((png_structp png_ptr));
3032#endif
3033
3034/* simple function to write the signature */
3035PNG_EXTERN void png_write_sig PNGARG((png_structp png_ptr));
3036
3037/* write various chunks */
3038
3039/* Write the IHDR chunk, and update the png_struct with the necessary
3040 * information.
3041 */
3042PNG_EXTERN void png_write_IHDR PNGARG((png_structp png_ptr, png_uint_32 width,
3043 png_uint_32 height,
3044 int bit_depth, int color_type, int compression_method, int filter_method,
3045 int interlace_method));
3046
3047PNG_EXTERN void png_write_PLTE PNGARG((png_structp png_ptr, png_colorp palette,
3048 png_uint_32 num_pal));
3049
3050PNG_EXTERN void png_write_IDAT PNGARG((png_structp png_ptr, png_bytep data,
3051 png_size_t length));
3052
3053PNG_EXTERN void png_write_IEND PNGARG((png_structp png_ptr));
3054
3055#if defined(PNG_WRITE_gAMA_SUPPORTED)
3056#ifdef PNG_FLOATING_POINT_SUPPORTED
3057PNG_EXTERN void png_write_gAMA PNGARG((png_structp png_ptr, double file_gamma));
3058#endif
3059#ifdef PNG_FIXED_POINT_SUPPORTED
3060PNG_EXTERN void png_write_gAMA_fixed PNGARG((png_structp png_ptr, png_fixed_point
3061 file_gamma));
3062#endif
3063#endif
3064
3065#if defined(PNG_WRITE_sBIT_SUPPORTED)
3066PNG_EXTERN void png_write_sBIT PNGARG((png_structp png_ptr, png_color_8p sbit,
3067 int color_type));
3068#endif
3069
3070#if defined(PNG_WRITE_cHRM_SUPPORTED)
3071#ifdef PNG_FLOATING_POINT_SUPPORTED
3072PNG_EXTERN void png_write_cHRM PNGARG((png_structp png_ptr,
3073 double white_x, double white_y,
3074 double red_x, double red_y, double green_x, double green_y,
3075 double blue_x, double blue_y));
3076#endif
3077#ifdef PNG_FIXED_POINT_SUPPORTED
3078PNG_EXTERN void png_write_cHRM_fixed PNGARG((png_structp png_ptr,
3079 png_fixed_point int_white_x, png_fixed_point int_white_y,
3080 png_fixed_point int_red_x, png_fixed_point int_red_y, png_fixed_point
3081 int_green_x, png_fixed_point int_green_y, png_fixed_point int_blue_x,
3082 png_fixed_point int_blue_y));
3083#endif
3084#endif
3085
3086#if defined(PNG_WRITE_sRGB_SUPPORTED)
3087PNG_EXTERN void png_write_sRGB PNGARG((png_structp png_ptr,
3088 int intent));
3089#endif
3090
3091#if defined(PNG_WRITE_iCCP_SUPPORTED)
3092PNG_EXTERN void png_write_iCCP PNGARG((png_structp png_ptr,
3093 png_charp name, int compression_type,
3094 png_charp profile, int proflen));
3095 /* Note to maintainer: profile should be png_bytep */
3096#endif
3097
3098#if defined(PNG_WRITE_sPLT_SUPPORTED)
3099PNG_EXTERN void png_write_sPLT PNGARG((png_structp png_ptr,
3100 png_sPLT_tp palette));
3101#endif
3102
3103#if defined(PNG_WRITE_tRNS_SUPPORTED)
3104PNG_EXTERN void png_write_tRNS PNGARG((png_structp png_ptr, png_bytep trans,
3105 png_color_16p values, int number, int color_type));
3106#endif
3107
3108#if defined(PNG_WRITE_bKGD_SUPPORTED)
3109PNG_EXTERN void png_write_bKGD PNGARG((png_structp png_ptr,
3110 png_color_16p values, int color_type));
3111#endif
3112
3113#if defined(PNG_WRITE_hIST_SUPPORTED)
3114PNG_EXTERN void png_write_hIST PNGARG((png_structp png_ptr, png_uint_16p hist,
3115 int num_hist));
3116#endif
3117
3118#if defined(PNG_WRITE_TEXT_SUPPORTED) || defined(PNG_WRITE_pCAL_SUPPORTED) || \
3119 defined(PNG_WRITE_iCCP_SUPPORTED) || defined(PNG_WRITE_sPLT_SUPPORTED)
3120PNG_EXTERN png_size_t png_check_keyword PNGARG((png_structp png_ptr,
3121 png_charp key, png_charpp new_key));
3122#endif
3123
3124#if defined(PNG_WRITE_tEXt_SUPPORTED)
3125PNG_EXTERN void png_write_tEXt PNGARG((png_structp png_ptr, png_charp key,
3126 png_charp text, png_size_t text_len));
3127#endif
3128
3129#if defined(PNG_WRITE_zTXt_SUPPORTED)
3130PNG_EXTERN void png_write_zTXt PNGARG((png_structp png_ptr, png_charp key,
3131 png_charp text, png_size_t text_len, int compression));
3132#endif
3133
3134#if defined(PNG_WRITE_iTXt_SUPPORTED)
3135PNG_EXTERN void png_write_iTXt PNGARG((png_structp png_ptr,
3136 int compression, png_charp key, png_charp lang, png_charp lang_key,
3137 png_charp text));
3138#endif
3139
3140#if defined(PNG_TEXT_SUPPORTED) /* Added at version 1.0.14 and 1.2.4 */
3141PNG_EXTERN int png_set_text_2 PNGARG((png_structp png_ptr,
3142 png_infop info_ptr, png_textp text_ptr, int num_text));
3143#endif
3144
3145#if defined(PNG_WRITE_oFFs_SUPPORTED)
3146PNG_EXTERN void png_write_oFFs PNGARG((png_structp png_ptr,
3147 png_int_32 x_offset, png_int_32 y_offset, int unit_type));
3148#endif
3149
3150#if defined(PNG_WRITE_pCAL_SUPPORTED)
3151PNG_EXTERN void png_write_pCAL PNGARG((png_structp png_ptr, png_charp purpose,
3152 png_int_32 X0, png_int_32 X1, int type, int nparams,
3153 png_charp units, png_charpp params));
3154#endif
3155
3156#if defined(PNG_WRITE_pHYs_SUPPORTED)
3157PNG_EXTERN void png_write_pHYs PNGARG((png_structp png_ptr,
3158 png_uint_32 x_pixels_per_unit, png_uint_32 y_pixels_per_unit,
3159 int unit_type));
3160#endif
3161
3162#if defined(PNG_WRITE_tIME_SUPPORTED)
3163PNG_EXTERN void png_write_tIME PNGARG((png_structp png_ptr,
3164 png_timep mod_time));
3165#endif
3166
3167#if defined(PNG_WRITE_sCAL_SUPPORTED)
3168#if defined(PNG_FLOATING_POINT_SUPPORTED) && !defined(PNG_NO_STDIO)
3169PNG_EXTERN void png_write_sCAL PNGARG((png_structp png_ptr,
3170 int unit, double width, double height));
3171#else
3172#ifdef PNG_FIXED_POINT_SUPPORTED
3173PNG_EXTERN void png_write_sCAL_s PNGARG((png_structp png_ptr,
3174 int unit, png_charp width, png_charp height));
3175#endif
3176#endif
3177#endif
3178
3179/* Called when finished processing a row of data */
3180PNG_EXTERN void png_write_finish_row PNGARG((png_structp png_ptr));
3181
3182/* Internal use only. Called before first row of data */
3183PNG_EXTERN void png_write_start_row PNGARG((png_structp png_ptr));
3184
3185#if defined(PNG_READ_GAMMA_SUPPORTED)
3186PNG_EXTERN void png_build_gamma_table PNGARG((png_structp png_ptr));
3187#endif
3188
3189/* combine a row of data, dealing with alpha, etc. if requested */
3190PNG_EXTERN void png_combine_row PNGARG((png_structp png_ptr, png_bytep row,
3191 int mask));
3192
3193#if defined(PNG_READ_INTERLACING_SUPPORTED)
3194/* expand an interlaced row */
3195/* OLD pre-1.0.9 interface:
3196PNG_EXTERN void png_do_read_interlace PNGARG((png_row_infop row_info,
3197 png_bytep row, int pass, png_uint_32 transformations));
3198 */
3199PNG_EXTERN void png_do_read_interlace PNGARG((png_structp png_ptr));
3200#endif
3201
3202/* GRR TO DO (2.0 or whenever): simplify other internal calling interfaces */
3203
3204#if defined(PNG_WRITE_INTERLACING_SUPPORTED)
3205/* grab pixels out of a row for an interlaced pass */
3206PNG_EXTERN void png_do_write_interlace PNGARG((png_row_infop row_info,
3207 png_bytep row, int pass));
3208#endif
3209
3210/* unfilter a row */
3211PNG_EXTERN void png_read_filter_row PNGARG((png_structp png_ptr,
3212 png_row_infop row_info, png_bytep row, png_bytep prev_row, int filter));
3213
3214/* Choose the best filter to use and filter the row data */
3215PNG_EXTERN void png_write_find_filter PNGARG((png_structp png_ptr,
3216 png_row_infop row_info));
3217
3218/* Write out the filtered row. */
3219PNG_EXTERN void png_write_filtered_row PNGARG((png_structp png_ptr,
3220 png_bytep filtered_row));
3221/* finish a row while reading, dealing with interlacing passes, etc. */
3222PNG_EXTERN void png_read_finish_row PNGARG((png_structp png_ptr));
3223
3224/* initialize the row buffers, etc. */
3225PNG_EXTERN void png_read_start_row PNGARG((png_structp png_ptr));
3226/* optional call to update the users info structure */
3227PNG_EXTERN void png_read_transform_info PNGARG((png_structp png_ptr,
3228 png_infop info_ptr));
3229
3230/* these are the functions that do the transformations */
3231#if defined(PNG_READ_FILLER_SUPPORTED)
3232PNG_EXTERN void png_do_read_filler PNGARG((png_row_infop row_info,
3233 png_bytep row, png_uint_32 filler, png_uint_32 flags));
3234#endif
3235
3236#if defined(PNG_READ_SWAP_ALPHA_SUPPORTED)
3237PNG_EXTERN void png_do_read_swap_alpha PNGARG((png_row_infop row_info,
3238 png_bytep row));
3239#endif
3240
3241#if defined(PNG_WRITE_SWAP_ALPHA_SUPPORTED)
3242PNG_EXTERN void png_do_write_swap_alpha PNGARG((png_row_infop row_info,
3243 png_bytep row));
3244#endif
3245
3246#if defined(PNG_READ_INVERT_ALPHA_SUPPORTED)
3247PNG_EXTERN void png_do_read_invert_alpha PNGARG((png_row_infop row_info,
3248 png_bytep row));
3249#endif
3250
3251#if defined(PNG_WRITE_INVERT_ALPHA_SUPPORTED)
3252PNG_EXTERN void png_do_write_invert_alpha PNGARG((png_row_infop row_info,
3253 png_bytep row));
3254#endif
3255
3256#if defined(PNG_WRITE_FILLER_SUPPORTED) || \
3257 defined(PNG_READ_STRIP_ALPHA_SUPPORTED)
3258PNG_EXTERN void png_do_strip_filler PNGARG((png_row_infop row_info,
3259 png_bytep row, png_uint_32 flags));
3260#endif
3261
3262#if defined(PNG_READ_SWAP_SUPPORTED) || defined(PNG_WRITE_SWAP_SUPPORTED)
3263PNG_EXTERN void png_do_swap PNGARG((png_row_infop row_info, png_bytep row));
3264#endif
3265
3266#if defined(PNG_READ_PACKSWAP_SUPPORTED) || defined(PNG_WRITE_PACKSWAP_SUPPORTED)
3267PNG_EXTERN void png_do_packswap PNGARG((png_row_infop row_info, png_bytep row));
3268#endif
3269
3270#if defined(PNG_READ_RGB_TO_GRAY_SUPPORTED)
3271PNG_EXTERN int png_do_rgb_to_gray PNGARG((png_structp png_ptr, png_row_infop
3272 row_info, png_bytep row));
3273#endif
3274
3275#if defined(PNG_READ_GRAY_TO_RGB_SUPPORTED)
3276PNG_EXTERN void png_do_gray_to_rgb PNGARG((png_row_infop row_info,
3277 png_bytep row));
3278#endif
3279
3280#if defined(PNG_READ_PACK_SUPPORTED)
3281PNG_EXTERN void png_do_unpack PNGARG((png_row_infop row_info, png_bytep row));
3282#endif
3283
3284#if defined(PNG_READ_SHIFT_SUPPORTED)
3285PNG_EXTERN void png_do_unshift PNGARG((png_row_infop row_info, png_bytep row,
3286 png_color_8p sig_bits));
3287#endif
3288
3289#if defined(PNG_READ_INVERT_SUPPORTED) || defined(PNG_WRITE_INVERT_SUPPORTED)
3290PNG_EXTERN void png_do_invert PNGARG((png_row_infop row_info, png_bytep row));
3291#endif
3292
3293#if defined(PNG_READ_16_TO_8_SUPPORTED)
3294PNG_EXTERN void png_do_chop PNGARG((png_row_infop row_info, png_bytep row));
3295#endif
3296
3297#if defined(PNG_READ_DITHER_SUPPORTED)
3298PNG_EXTERN void png_do_dither PNGARG((png_row_infop row_info,
3299 png_bytep row, png_bytep palette_lookup, png_bytep dither_lookup));
3300
3301# if defined(PNG_CORRECT_PALETTE_SUPPORTED)
3302PNG_EXTERN void png_correct_palette PNGARG((png_structp png_ptr,
3303 png_colorp palette, int num_palette));
3304# endif
3305#endif
3306
3307#if defined(PNG_READ_BGR_SUPPORTED) || defined(PNG_WRITE_BGR_SUPPORTED)
3308PNG_EXTERN void png_do_bgr PNGARG((png_row_infop row_info, png_bytep row));
3309#endif
3310
3311#if defined(PNG_WRITE_PACK_SUPPORTED)
3312PNG_EXTERN void png_do_pack PNGARG((png_row_infop row_info,
3313 png_bytep row, png_uint_32 bit_depth));
3314#endif
3315
3316#if defined(PNG_WRITE_SHIFT_SUPPORTED)
3317PNG_EXTERN void png_do_shift PNGARG((png_row_infop row_info, png_bytep row,
3318 png_color_8p bit_depth));
3319#endif
3320
3321#if defined(PNG_READ_BACKGROUND_SUPPORTED)
3322#if defined(PNG_READ_GAMMA_SUPPORTED)
3323PNG_EXTERN void png_do_background PNGARG((png_row_infop row_info, png_bytep row,
3324 png_color_16p trans_values, png_color_16p background,
3325 png_color_16p background_1,
3326 png_bytep gamma_table, png_bytep gamma_from_1, png_bytep gamma_to_1,
3327 png_uint_16pp gamma_16, png_uint_16pp gamma_16_from_1,
3328 png_uint_16pp gamma_16_to_1, int gamma_shift));
3329#else
3330PNG_EXTERN void png_do_background PNGARG((png_row_infop row_info, png_bytep row,
3331 png_color_16p trans_values, png_color_16p background));
3332#endif
3333#endif
3334
3335#if defined(PNG_READ_GAMMA_SUPPORTED)
3336PNG_EXTERN void png_do_gamma PNGARG((png_row_infop row_info, png_bytep row,
3337 png_bytep gamma_table, png_uint_16pp gamma_16_table,
3338 int gamma_shift));
3339#endif
3340
3341#if defined(PNG_READ_EXPAND_SUPPORTED)
3342PNG_EXTERN void png_do_expand_palette PNGARG((png_row_infop row_info,
3343 png_bytep row, png_colorp palette, png_bytep trans, int num_trans));
3344PNG_EXTERN void png_do_expand PNGARG((png_row_infop row_info,
3345 png_bytep row, png_color_16p trans_value));
3346#endif
3347
3348/* The following decodes the appropriate chunks, and does error correction,
3349 * then calls the appropriate callback for the chunk if it is valid.
3350 */
3351
3352/* decode the IHDR chunk */
3353PNG_EXTERN void png_handle_IHDR PNGARG((png_structp png_ptr, png_infop info_ptr,
3354 png_uint_32 length));
3355PNG_EXTERN void png_handle_PLTE PNGARG((png_structp png_ptr, png_infop info_ptr,
3356 png_uint_32 length));
3357PNG_EXTERN void png_handle_IEND PNGARG((png_structp png_ptr, png_infop info_ptr,
3358 png_uint_32 length));
3359
3360#if defined(PNG_READ_bKGD_SUPPORTED)
3361PNG_EXTERN void png_handle_bKGD PNGARG((png_structp png_ptr, png_infop info_ptr,
3362 png_uint_32 length));
3363#endif
3364
3365#if defined(PNG_READ_cHRM_SUPPORTED)
3366PNG_EXTERN void png_handle_cHRM PNGARG((png_structp png_ptr, png_infop info_ptr,
3367 png_uint_32 length));
3368#endif
3369
3370#if defined(PNG_READ_gAMA_SUPPORTED)
3371PNG_EXTERN void png_handle_gAMA PNGARG((png_structp png_ptr, png_infop info_ptr,
3372 png_uint_32 length));
3373#endif
3374
3375#if defined(PNG_READ_hIST_SUPPORTED)
3376PNG_EXTERN void png_handle_hIST PNGARG((png_structp png_ptr, png_infop info_ptr,
3377 png_uint_32 length));
3378#endif
3379
3380#if defined(PNG_READ_iCCP_SUPPORTED)
3381extern void png_handle_iCCP PNGARG((png_structp png_ptr, png_infop info_ptr,
3382 png_uint_32 length));
3383#endif /* PNG_READ_iCCP_SUPPORTED */
3384
3385#if defined(PNG_READ_iTXt_SUPPORTED)
3386PNG_EXTERN void png_handle_iTXt PNGARG((png_structp png_ptr, png_infop info_ptr,
3387 png_uint_32 length));
3388#endif
3389
3390#if defined(PNG_READ_oFFs_SUPPORTED)
3391PNG_EXTERN void png_handle_oFFs PNGARG((png_structp png_ptr, png_infop info_ptr,
3392 png_uint_32 length));
3393#endif
3394
3395#if defined(PNG_READ_pCAL_SUPPORTED)
3396PNG_EXTERN void png_handle_pCAL PNGARG((png_structp png_ptr, png_infop info_ptr,
3397 png_uint_32 length));
3398#endif
3399
3400#if defined(PNG_READ_pHYs_SUPPORTED)
3401PNG_EXTERN void png_handle_pHYs PNGARG((png_structp png_ptr, png_infop info_ptr,
3402 png_uint_32 length));
3403#endif
3404
3405#if defined(PNG_READ_sBIT_SUPPORTED)
3406PNG_EXTERN void png_handle_sBIT PNGARG((png_structp png_ptr, png_infop info_ptr,
3407 png_uint_32 length));
3408#endif
3409
3410#if defined(PNG_READ_sCAL_SUPPORTED)
3411PNG_EXTERN void png_handle_sCAL PNGARG((png_structp png_ptr, png_infop info_ptr,
3412 png_uint_32 length));
3413#endif
3414
3415#if defined(PNG_READ_sPLT_SUPPORTED)
3416extern void png_handle_sPLT PNGARG((png_structp png_ptr, png_infop info_ptr,
3417 png_uint_32 length));
3418#endif /* PNG_READ_sPLT_SUPPORTED */
3419
3420#if defined(PNG_READ_sRGB_SUPPORTED)
3421PNG_EXTERN void png_handle_sRGB PNGARG((png_structp png_ptr, png_infop info_ptr,
3422 png_uint_32 length));
3423#endif
3424
3425#if defined(PNG_READ_tEXt_SUPPORTED)
3426PNG_EXTERN void png_handle_tEXt PNGARG((png_structp png_ptr, png_infop info_ptr,
3427 png_uint_32 length));
3428#endif
3429
3430#if defined(PNG_READ_tIME_SUPPORTED)
3431PNG_EXTERN void png_handle_tIME PNGARG((png_structp png_ptr, png_infop info_ptr,
3432 png_uint_32 length));
3433#endif
3434
3435#if defined(PNG_READ_tRNS_SUPPORTED)
3436PNG_EXTERN void png_handle_tRNS PNGARG((png_structp png_ptr, png_infop info_ptr,
3437 png_uint_32 length));
3438#endif
3439
3440#if defined(PNG_READ_zTXt_SUPPORTED)
3441PNG_EXTERN void png_handle_zTXt PNGARG((png_structp png_ptr, png_infop info_ptr,
3442 png_uint_32 length));
3443#endif
3444
3445PNG_EXTERN void png_handle_unknown PNGARG((png_structp png_ptr,
3446 png_infop info_ptr, png_uint_32 length));
3447
3448PNG_EXTERN void png_check_chunk_name PNGARG((png_structp png_ptr,
3449 png_bytep chunk_name));
3450
3451/* handle the transformations for reading and writing */
3452PNG_EXTERN void png_do_read_transformations PNGARG((png_structp png_ptr));
3453PNG_EXTERN void png_do_write_transformations PNGARG((png_structp png_ptr));
3454
3455PNG_EXTERN void png_init_read_transformations PNGARG((png_structp png_ptr));
3456
3457#ifdef PNG_PROGRESSIVE_READ_SUPPORTED
3458PNG_EXTERN void png_push_read_chunk PNGARG((png_structp png_ptr,
3459 png_infop info_ptr));
3460PNG_EXTERN void png_push_read_sig PNGARG((png_structp png_ptr,
3461 png_infop info_ptr));
3462PNG_EXTERN void png_push_check_crc PNGARG((png_structp png_ptr));
3463PNG_EXTERN void png_push_crc_skip PNGARG((png_structp png_ptr,
3464 png_uint_32 length));
3465PNG_EXTERN void png_push_crc_finish PNGARG((png_structp png_ptr));
3466PNG_EXTERN void png_push_save_buffer PNGARG((png_structp png_ptr));
3467PNG_EXTERN void png_push_restore_buffer PNGARG((png_structp png_ptr,
3468 png_bytep buffer, png_size_t buffer_length));
3469PNG_EXTERN void png_push_read_IDAT PNGARG((png_structp png_ptr));
3470PNG_EXTERN void png_process_IDAT_data PNGARG((png_structp png_ptr,
3471 png_bytep buffer, png_size_t buffer_length));
3472PNG_EXTERN void png_push_process_row PNGARG((png_structp png_ptr));
3473PNG_EXTERN void png_push_handle_unknown PNGARG((png_structp png_ptr,
3474 png_infop info_ptr, png_uint_32 length));
3475PNG_EXTERN void png_push_have_info PNGARG((png_structp png_ptr,
3476 png_infop info_ptr));
3477PNG_EXTERN void png_push_have_end PNGARG((png_structp png_ptr,
3478 png_infop info_ptr));
3479PNG_EXTERN void png_push_have_row PNGARG((png_structp png_ptr, png_bytep row));
3480PNG_EXTERN void png_push_read_end PNGARG((png_structp png_ptr,
3481 png_infop info_ptr));
3482PNG_EXTERN void png_process_some_data PNGARG((png_structp png_ptr,
3483 png_infop info_ptr));
3484PNG_EXTERN void png_read_push_finish_row PNGARG((png_structp png_ptr));
3485#if defined(PNG_READ_tEXt_SUPPORTED)
3486PNG_EXTERN void png_push_handle_tEXt PNGARG((png_structp png_ptr,
3487 png_infop info_ptr, png_uint_32 length));
3488PNG_EXTERN void png_push_read_tEXt PNGARG((png_structp png_ptr,
3489 png_infop info_ptr));
3490#endif
3491#if defined(PNG_READ_zTXt_SUPPORTED)
3492PNG_EXTERN void png_push_handle_zTXt PNGARG((png_structp png_ptr,
3493 png_infop info_ptr, png_uint_32 length));
3494PNG_EXTERN void png_push_read_zTXt PNGARG((png_structp png_ptr,
3495 png_infop info_ptr));
3496#endif
3497#if defined(PNG_READ_iTXt_SUPPORTED)
3498PNG_EXTERN void png_push_handle_iTXt PNGARG((png_structp png_ptr,
3499 png_infop info_ptr, png_uint_32 length));
3500PNG_EXTERN void png_push_read_iTXt PNGARG((png_structp png_ptr,
3501 png_infop info_ptr));
3502#endif
3503
3504#endif /* PNG_PROGRESSIVE_READ_SUPPORTED */
3505
3506#ifdef PNG_MNG_FEATURES_SUPPORTED
3507PNG_EXTERN void png_do_read_intrapixel PNGARG((png_row_infop row_info,
3508 png_bytep row));
3509PNG_EXTERN void png_do_write_intrapixel PNGARG((png_row_infop row_info,
3510 png_bytep row));
3511#endif
3512
3513#if defined(PNG_ASSEMBLER_CODE_SUPPORTED)
3514#if defined(PNG_MMX_CODE_SUPPORTED)
3515/* png.c */ /* PRIVATE */
3516PNG_EXTERN void png_init_mmx_flags PNGARG((png_structp png_ptr));
3517#endif
3518#endif
3519
3520#if defined(PNG_INCH_CONVERSIONS) && defined(PNG_FLOATING_POINT_SUPPORTED)
3521PNG_EXTERN png_uint_32 png_get_pixels_per_inch PNGARG((png_structp png_ptr,
3522png_infop info_ptr));
3523
3524PNG_EXTERN png_uint_32 png_get_x_pixels_per_inch PNGARG((png_structp png_ptr,
3525png_infop info_ptr));
3526
3527PNG_EXTERN png_uint_32 png_get_y_pixels_per_inch PNGARG((png_structp png_ptr,
3528png_infop info_ptr));
3529
3530PNG_EXTERN float png_get_x_offset_inches PNGARG((png_structp png_ptr,
3531png_infop info_ptr));
3532
3533PNG_EXTERN float png_get_y_offset_inches PNGARG((png_structp png_ptr,
3534png_infop info_ptr));
3535
3536#if defined(PNG_pHYs_SUPPORTED)
3537PNG_EXTERN png_uint_32 png_get_pHYs_dpi PNGARG((png_structp png_ptr,
3538png_infop info_ptr, png_uint_32 *res_x, png_uint_32 *res_y, int *unit_type));
3539#endif /* PNG_pHYs_SUPPORTED */
3540#endif /* PNG_INCH_CONVERSIONS && PNG_FLOATING_POINT_SUPPORTED */
3541
3542/* Maintainer: Put new private prototypes here ^ and in libpngpf.3 */
3543
3544#endif /* PNG_INTERNAL */
3545
3546#ifdef __cplusplus
3547}
3548#endif
3549
3550#endif /* PNG_VERSION_INFO_ONLY */
3551/* do not put anything past this line */
3552#endif /* PNG_H */
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