[DDK]: Merge 46183 from header-branch.
[reactos.git] / rosapps / lib / libpng / png.h
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 #endif
425
426 /* include all user configurable info, including optional assembler routines */
427 #include "pngconf.h"
428
429 /*
430 * Added at libpng-1.2.8 */
431 /* Ref MSDN: Private as priority over Special
432 * VS_FF_PRIVATEBUILD File *was not* built using standard release
433 * procedures. If this value is given, the StringFileInfo block must
434 * contain a PrivateBuild string.
435 *
436 * VS_FF_SPECIALBUILD File *was* built by the original company using
437 * standard release procedures but is a variation of the standard
438 * file of the same version number. If this value is given, the
439 * StringFileInfo block must contain a SpecialBuild string.
440 */
441
442 #if defined(PNG_USER_PRIVATEBUILD)
443 # define PNG_LIBPNG_BUILD_TYPE \
444 (PNG_LIBPNG_BUILD_BASE_TYPE | PNG_LIBPNG_BUILD_PRIVATE)
445 #else
446 # if defined(PNG_LIBPNG_SPECIALBUILD)
447 # define PNG_LIBPNG_BUILD_TYPE \
448 (PNG_LIBPNG_BUILD_BASE_TYPE | PNG_LIBPNG_BUILD_SPECIAL)
449 # else
450 # define PNG_LIBPNG_BUILD_TYPE (PNG_LIBPNG_BUILD_BASE_TYPE)
451 # endif
452 #endif
453
454 #ifndef PNG_VERSION_INFO_ONLY
455
456 /* Inhibit C++ name-mangling for libpng functions but not for system calls. */
457 #ifdef __cplusplus
458 extern "C" {
459 #endif /* __cplusplus */
460
461 /* This file is arranged in several sections. The first section contains
462 * structure and type definitions. The second section contains the external
463 * library functions, while the third has the internal library functions,
464 * which applications aren't expected to use directly.
465 */
466
467 #ifndef PNG_NO_TYPECAST_NULL
468 #define int_p_NULL (int *)NULL
469 #define png_bytep_NULL (png_bytep)NULL
470 #define png_bytepp_NULL (png_bytepp)NULL
471 #define png_doublep_NULL (png_doublep)NULL
472 #define png_error_ptr_NULL (png_error_ptr)NULL
473 #define png_flush_ptr_NULL (png_flush_ptr)NULL
474 #define png_free_ptr_NULL (png_free_ptr)NULL
475 #define png_infopp_NULL (png_infopp)NULL
476 #define png_malloc_ptr_NULL (png_malloc_ptr)NULL
477 #define png_read_status_ptr_NULL (png_read_status_ptr)NULL
478 #define png_rw_ptr_NULL (png_rw_ptr)NULL
479 #define png_structp_NULL (png_structp)NULL
480 #define png_uint_16p_NULL (png_uint_16p)NULL
481 #define png_voidp_NULL (png_voidp)NULL
482 #define png_write_status_ptr_NULL (png_write_status_ptr)NULL
483 #else
484 #define int_p_NULL NULL
485 #define png_bytep_NULL NULL
486 #define png_bytepp_NULL NULL
487 #define png_doublep_NULL NULL
488 #define png_error_ptr_NULL NULL
489 #define png_flush_ptr_NULL NULL
490 #define png_free_ptr_NULL NULL
491 #define png_infopp_NULL NULL
492 #define png_malloc_ptr_NULL NULL
493 #define png_read_status_ptr_NULL NULL
494 #define png_rw_ptr_NULL NULL
495 #define png_structp_NULL NULL
496 #define png_uint_16p_NULL NULL
497 #define png_voidp_NULL NULL
498 #define png_write_status_ptr_NULL NULL
499 #endif
500
501 /* variables declared in png.c - only it needs to define PNG_NO_EXTERN */
502 #if !defined(PNG_NO_EXTERN) || defined(PNG_ALWAYS_EXTERN)
503 /* Version information for C files, stored in png.c. This had better match
504 * the version above.
505 */
506 #ifdef PNG_USE_GLOBAL_ARRAYS
507 PNG_EXPORT_VAR (PNG_CONST char) png_libpng_ver[18];
508 /* need room for 99.99.99beta99z */
509 #else
510 #define png_libpng_ver png_get_header_ver(NULL)
511 #endif
512
513 #ifdef PNG_USE_GLOBAL_ARRAYS
514 /* This was removed in version 1.0.5c */
515 /* Structures to facilitate easy interlacing. See png.c for more details */
516 PNG_EXPORT_VAR (PNG_CONST int FARDATA) png_pass_start[7];
517 PNG_EXPORT_VAR (PNG_CONST int FARDATA) png_pass_inc[7];
518 PNG_EXPORT_VAR (PNG_CONST int FARDATA) png_pass_ystart[7];
519 PNG_EXPORT_VAR (PNG_CONST int FARDATA) png_pass_yinc[7];
520 PNG_EXPORT_VAR (PNG_CONST int FARDATA) png_pass_mask[7];
521 PNG_EXPORT_VAR (PNG_CONST int FARDATA) png_pass_dsp_mask[7];
522 /* This isn't currently used. If you need it, see png.c for more details.
523 PNG_EXPORT_VAR (PNG_CONST int FARDATA) png_pass_height[7];
524 */
525 #endif
526
527 #endif /* PNG_NO_EXTERN */
528
529 /* Three color definitions. The order of the red, green, and blue, (and the
530 * exact size) is not important, although the size of the fields need to
531 * be png_byte or png_uint_16 (as defined below).
532 */
533 typedef struct png_color_struct
534 {
535 png_byte red;
536 png_byte green;
537 png_byte blue;
538 } png_color;
539 typedef png_color FAR * png_colorp;
540 typedef png_color FAR * FAR * png_colorpp;
541
542 typedef struct png_color_16_struct
543 {
544 png_byte index; /* used for palette files */
545 png_uint_16 red; /* for use in red green blue files */
546 png_uint_16 green;
547 png_uint_16 blue;
548 png_uint_16 gray; /* for use in grayscale files */
549 } png_color_16;
550 typedef png_color_16 FAR * png_color_16p;
551 typedef png_color_16 FAR * FAR * png_color_16pp;
552
553 typedef struct png_color_8_struct
554 {
555 png_byte red; /* for use in red green blue files */
556 png_byte green;
557 png_byte blue;
558 png_byte gray; /* for use in grayscale files */
559 png_byte alpha; /* for alpha channel files */
560 } png_color_8;
561 typedef png_color_8 FAR * png_color_8p;
562 typedef png_color_8 FAR * FAR * png_color_8pp;
563
564 /*
565 * The following two structures are used for the in-core representation
566 * of sPLT chunks.
567 */
568 typedef struct png_sPLT_entry_struct
569 {
570 png_uint_16 red;
571 png_uint_16 green;
572 png_uint_16 blue;
573 png_uint_16 alpha;
574 png_uint_16 frequency;
575 } png_sPLT_entry;
576 typedef png_sPLT_entry FAR * png_sPLT_entryp;
577 typedef png_sPLT_entry FAR * FAR * png_sPLT_entrypp;
578
579 /* When the depth of the sPLT palette is 8 bits, the color and alpha samples
580 * occupy the LSB of their respective members, and the MSB of each member
581 * is zero-filled. The frequency member always occupies the full 16 bits.
582 */
583
584 typedef struct png_sPLT_struct
585 {
586 png_charp name; /* palette name */
587 png_byte depth; /* depth of palette samples */
588 png_sPLT_entryp entries; /* palette entries */
589 png_int_32 nentries; /* number of palette entries */
590 } png_sPLT_t;
591 typedef png_sPLT_t FAR * png_sPLT_tp;
592 typedef png_sPLT_t FAR * FAR * png_sPLT_tpp;
593
594 #ifdef PNG_TEXT_SUPPORTED
595 /* png_text holds the contents of a text/ztxt/itxt chunk in a PNG file,
596 * and whether that contents is compressed or not. The "key" field
597 * points to a regular zero-terminated C string. The "text", "lang", and
598 * "lang_key" fields can be regular C strings, empty strings, or NULL pointers.
599 * However, the * structure returned by png_get_text() will always contain
600 * regular zero-terminated C strings (possibly empty), never NULL pointers,
601 * so they can be safely used in printf() and other string-handling functions.
602 */
603 typedef struct png_text_struct
604 {
605 int compression; /* compression value:
606 -1: tEXt, none
607 0: zTXt, deflate
608 1: iTXt, none
609 2: iTXt, deflate */
610 png_charp key; /* keyword, 1-79 character description of "text" */
611 png_charp text; /* comment, may be an empty string (ie "")
612 or a NULL pointer */
613 png_size_t text_length; /* length of the text string */
614 #ifdef PNG_iTXt_SUPPORTED
615 png_size_t itxt_length; /* length of the itxt string */
616 png_charp lang; /* language code, 0-79 characters
617 or a NULL pointer */
618 png_charp lang_key; /* keyword translated UTF-8 string, 0 or more
619 chars or a NULL pointer */
620 #endif
621 } png_text;
622 typedef png_text FAR * png_textp;
623 typedef png_text FAR * FAR * png_textpp;
624 #endif
625
626 /* Supported compression types for text in PNG files (tEXt, and zTXt).
627 * The values of the PNG_TEXT_COMPRESSION_ defines should NOT be changed. */
628 #define PNG_TEXT_COMPRESSION_NONE_WR -3
629 #define PNG_TEXT_COMPRESSION_zTXt_WR -2
630 #define PNG_TEXT_COMPRESSION_NONE -1
631 #define PNG_TEXT_COMPRESSION_zTXt 0
632 #define PNG_ITXT_COMPRESSION_NONE 1
633 #define PNG_ITXT_COMPRESSION_zTXt 2
634 #define PNG_TEXT_COMPRESSION_LAST 3 /* Not a valid value */
635
636 /* png_time is a way to hold the time in an machine independent way.
637 * Two conversions are provided, both from time_t and struct tm. There
638 * is no portable way to convert to either of these structures, as far
639 * as I know. If you know of a portable way, send it to me. As a side
640 * note - PNG has always been Year 2000 compliant!
641 */
642 typedef struct png_time_struct
643 {
644 png_uint_16 year; /* full year, as in, 1995 */
645 png_byte month; /* month of year, 1 - 12 */
646 png_byte day; /* day of month, 1 - 31 */
647 png_byte hour; /* hour of day, 0 - 23 */
648 png_byte minute; /* minute of hour, 0 - 59 */
649 png_byte second; /* second of minute, 0 - 60 (for leap seconds) */
650 } png_time;
651 typedef png_time FAR * png_timep;
652 typedef png_time FAR * FAR * png_timepp;
653
654 #if defined(PNG_UNKNOWN_CHUNKS_SUPPORTED)
655 /* png_unknown_chunk is a structure to hold queued chunks for which there is
656 * no specific support. The idea is that we can use this to queue
657 * up private chunks for output even though the library doesn't actually
658 * know about their semantics.
659 */
660 #define PNG_CHUNK_NAME_LENGTH 5
661 typedef struct png_unknown_chunk_t
662 {
663 png_byte name[PNG_CHUNK_NAME_LENGTH];
664 png_byte *data;
665 png_size_t size;
666
667 /* libpng-using applications should NOT directly modify this byte. */
668 png_byte location; /* mode of operation at read time */
669 }
670 png_unknown_chunk;
671 typedef png_unknown_chunk FAR * png_unknown_chunkp;
672 typedef png_unknown_chunk FAR * FAR * png_unknown_chunkpp;
673 #endif
674
675 /* png_info is a structure that holds the information in a PNG file so
676 * that the application can find out the characteristics of the image.
677 * If you are reading the file, this structure will tell you what is
678 * in the PNG file. If you are writing the file, fill in the information
679 * you want to put into the PNG file, then call png_write_info().
680 * The names chosen should be very close to the PNG specification, so
681 * consult that document for information about the meaning of each field.
682 *
683 * With libpng < 0.95, it was only possible to directly set and read the
684 * the values in the png_info_struct, which meant that the contents and
685 * order of the values had to remain fixed. With libpng 0.95 and later,
686 * however, there are now functions that abstract the contents of
687 * png_info_struct from the application, so this makes it easier to use
688 * libpng with dynamic libraries, and even makes it possible to use
689 * libraries that don't have all of the libpng ancillary chunk-handing
690 * functionality.
691 *
692 * In any case, the order of the parameters in png_info_struct should NOT
693 * be changed for as long as possible to keep compatibility with applications
694 * that use the old direct-access method with png_info_struct.
695 *
696 * The following members may have allocated storage attached that should be
697 * cleaned up before the structure is discarded: palette, trans, text,
698 * pcal_purpose, pcal_units, pcal_params, hist, iccp_name, iccp_profile,
699 * splt_palettes, scal_unit, row_pointers, and unknowns. By default, these
700 * are automatically freed when the info structure is deallocated, if they were
701 * allocated internally by libpng. This behavior can be changed by means
702 * of the png_data_freer() function.
703 *
704 * More allocation details: all the chunk-reading functions that
705 * change these members go through the corresponding png_set_*
706 * functions. A function to clear these members is available: see
707 * png_free_data(). The png_set_* functions do not depend on being
708 * able to point info structure members to any of the storage they are
709 * passed (they make their own copies), EXCEPT that the png_set_text
710 * functions use the same storage passed to them in the text_ptr or
711 * itxt_ptr structure argument, and the png_set_rows and png_set_unknowns
712 * functions do not make their own copies.
713 */
714 typedef struct png_info_struct
715 {
716 /* the following are necessary for every PNG file */
717 png_uint_32 width; /* width of image in pixels (from IHDR) */
718 png_uint_32 height; /* height of image in pixels (from IHDR) */
719 png_uint_32 valid; /* valid chunk data (see PNG_INFO_ below) */
720 png_uint_32 rowbytes; /* bytes needed to hold an untransformed row */
721 png_colorp palette; /* array of color values (valid & PNG_INFO_PLTE) */
722 png_uint_16 num_palette; /* number of color entries in "palette" (PLTE) */
723 png_uint_16 num_trans; /* number of transparent palette color (tRNS) */
724 png_byte bit_depth; /* 1, 2, 4, 8, or 16 bits/channel (from IHDR) */
725 png_byte color_type; /* see PNG_COLOR_TYPE_ below (from IHDR) */
726 /* The following three should have been named *_method not *_type */
727 png_byte compression_type; /* must be PNG_COMPRESSION_TYPE_BASE (IHDR) */
728 png_byte filter_type; /* must be PNG_FILTER_TYPE_BASE (from IHDR) */
729 png_byte interlace_type; /* One of PNG_INTERLACE_NONE, PNG_INTERLACE_ADAM7 */
730
731 /* The following is informational only on read, and not used on writes. */
732 png_byte channels; /* number of data channels per pixel (1, 2, 3, 4) */
733 png_byte pixel_depth; /* number of bits per pixel */
734 png_byte spare_byte; /* to align the data, and for future use */
735 png_byte signature[8]; /* magic bytes read by libpng from start of file */
736
737 /* The rest of the data is optional. If you are reading, check the
738 * valid field to see if the information in these are valid. If you
739 * are writing, set the valid field to those chunks you want written,
740 * and initialize the appropriate fields below.
741 */
742
743 #if defined(PNG_gAMA_SUPPORTED) && defined(PNG_FLOATING_POINT_SUPPORTED)
744 /* The gAMA chunk describes the gamma characteristics of the system
745 * on which the image was created, normally in the range [1.0, 2.5].
746 * Data is valid if (valid & PNG_INFO_gAMA) is non-zero.
747 */
748 float gamma; /* gamma value of image, if (valid & PNG_INFO_gAMA) */
749 #endif
750
751 #if defined(PNG_sRGB_SUPPORTED)
752 /* GR-P, 0.96a */
753 /* Data valid if (valid & PNG_INFO_sRGB) non-zero. */
754 png_byte srgb_intent; /* sRGB rendering intent [0, 1, 2, or 3] */
755 #endif
756
757 #if defined(PNG_TEXT_SUPPORTED)
758 /* The tEXt, and zTXt chunks contain human-readable textual data in
759 * uncompressed, compressed, and optionally compressed forms, respectively.
760 * The data in "text" is an array of pointers to uncompressed,
761 * null-terminated C strings. Each chunk has a keyword that describes the
762 * textual data contained in that chunk. Keywords are not required to be
763 * unique, and the text string may be empty. Any number of text chunks may
764 * be in an image.
765 */
766 int num_text; /* number of comments read/to write */
767 int max_text; /* current size of text array */
768 png_textp text; /* array of comments read/to write */
769 #endif /* PNG_TEXT_SUPPORTED */
770
771 #if defined(PNG_tIME_SUPPORTED)
772 /* The tIME chunk holds the last time the displayed image data was
773 * modified. See the png_time struct for the contents of this struct.
774 */
775 png_time mod_time;
776 #endif
777
778 #if defined(PNG_sBIT_SUPPORTED)
779 /* The sBIT chunk specifies the number of significant high-order bits
780 * in the pixel data. Values are in the range [1, bit_depth], and are
781 * only specified for the channels in the pixel data. The contents of
782 * the low-order bits is not specified. Data is valid if
783 * (valid & PNG_INFO_sBIT) is non-zero.
784 */
785 png_color_8 sig_bit; /* significant bits in color channels */
786 #endif
787
788 #if defined(PNG_tRNS_SUPPORTED) || defined(PNG_READ_EXPAND_SUPPORTED) || \
789 defined(PNG_READ_BACKGROUND_SUPPORTED)
790 /* The tRNS chunk supplies transparency data for paletted images and
791 * other image types that don't need a full alpha channel. There are
792 * "num_trans" transparency values for a paletted image, stored in the
793 * same order as the palette colors, starting from index 0. Values
794 * for the data are in the range [0, 255], ranging from fully transparent
795 * to fully opaque, respectively. For non-paletted images, there is a
796 * single color specified that should be treated as fully transparent.
797 * Data is valid if (valid & PNG_INFO_tRNS) is non-zero.
798 */
799 png_bytep trans; /* transparent values for paletted image */
800 png_color_16 trans_values; /* transparent color for non-palette image */
801 #endif
802
803 #if defined(PNG_bKGD_SUPPORTED) || defined(PNG_READ_BACKGROUND_SUPPORTED)
804 /* The bKGD chunk gives the suggested image background color if the
805 * display program does not have its own background color and the image
806 * is needs to composited onto a background before display. The colors
807 * in "background" are normally in the same color space/depth as the
808 * pixel data. Data is valid if (valid & PNG_INFO_bKGD) is non-zero.
809 */
810 png_color_16 background;
811 #endif
812
813 #if defined(PNG_oFFs_SUPPORTED)
814 /* The oFFs chunk gives the offset in "offset_unit_type" units rightwards
815 * and downwards from the top-left corner of the display, page, or other
816 * application-specific co-ordinate space. See the PNG_OFFSET_ defines
817 * below for the unit types. Valid if (valid & PNG_INFO_oFFs) non-zero.
818 */
819 png_int_32 x_offset; /* x offset on page */
820 png_int_32 y_offset; /* y offset on page */
821 png_byte offset_unit_type; /* offset units type */
822 #endif
823
824 #if defined(PNG_pHYs_SUPPORTED)
825 /* The pHYs chunk gives the physical pixel density of the image for
826 * display or printing in "phys_unit_type" units (see PNG_RESOLUTION_
827 * defines below). Data is valid if (valid & PNG_INFO_pHYs) is non-zero.
828 */
829 png_uint_32 x_pixels_per_unit; /* horizontal pixel density */
830 png_uint_32 y_pixels_per_unit; /* vertical pixel density */
831 png_byte phys_unit_type; /* resolution type (see PNG_RESOLUTION_ below) */
832 #endif
833
834 #if defined(PNG_hIST_SUPPORTED)
835 /* The hIST chunk contains the relative frequency or importance of the
836 * various palette entries, so that a viewer can intelligently select a
837 * reduced-color palette, if required. Data is an array of "num_palette"
838 * values in the range [0,65535]. Data valid if (valid & PNG_INFO_hIST)
839 * is non-zero.
840 */
841 png_uint_16p hist;
842 #endif
843
844 #ifdef PNG_cHRM_SUPPORTED
845 /* The cHRM chunk describes the CIE color characteristics of the monitor
846 * on which the PNG was created. This data allows the viewer to do gamut
847 * mapping of the input image to ensure that the viewer sees the same
848 * colors in the image as the creator. Values are in the range
849 * [0.0, 0.8]. Data valid if (valid & PNG_INFO_cHRM) non-zero.
850 */
851 #ifdef PNG_FLOATING_POINT_SUPPORTED
852 float x_white;
853 float y_white;
854 float x_red;
855 float y_red;
856 float x_green;
857 float y_green;
858 float x_blue;
859 float y_blue;
860 #endif
861 #endif
862
863 #if defined(PNG_pCAL_SUPPORTED)
864 /* The pCAL chunk describes a transformation between the stored pixel
865 * values and original physical data values used to create the image.
866 * The integer range [0, 2^bit_depth - 1] maps to the floating-point
867 * range given by [pcal_X0, pcal_X1], and are further transformed by a
868 * (possibly non-linear) transformation function given by "pcal_type"
869 * and "pcal_params" into "pcal_units". Please see the PNG_EQUATION_
870 * defines below, and the PNG-Group's PNG extensions document for a
871 * complete description of the transformations and how they should be
872 * implemented, and for a description of the ASCII parameter strings.
873 * Data values are valid if (valid & PNG_INFO_pCAL) non-zero.
874 */
875 png_charp pcal_purpose; /* pCAL chunk description string */
876 png_int_32 pcal_X0; /* minimum value */
877 png_int_32 pcal_X1; /* maximum value */
878 png_charp pcal_units; /* Latin-1 string giving physical units */
879 png_charpp pcal_params; /* ASCII strings containing parameter values */
880 png_byte pcal_type; /* equation type (see PNG_EQUATION_ below) */
881 png_byte pcal_nparams; /* number of parameters given in pcal_params */
882 #endif
883
884 /* New members added in libpng-1.0.6 */
885 #ifdef PNG_FREE_ME_SUPPORTED
886 png_uint_32 free_me; /* flags items libpng is responsible for freeing */
887 #endif
888
889 #if defined(PNG_UNKNOWN_CHUNKS_SUPPORTED)
890 /* storage for unknown chunks that the library doesn't recognize. */
891 png_unknown_chunkp unknown_chunks;
892 png_size_t unknown_chunks_num;
893 #endif
894
895 #if defined(PNG_iCCP_SUPPORTED)
896 /* iCCP chunk data. */
897 png_charp iccp_name; /* profile name */
898 png_charp iccp_profile; /* International Color Consortium profile data */
899 /* Note to maintainer: should be png_bytep */
900 png_uint_32 iccp_proflen; /* ICC profile data length */
901 png_byte iccp_compression; /* Always zero */
902 #endif
903
904 #if defined(PNG_sPLT_SUPPORTED)
905 /* data on sPLT chunks (there may be more than one). */
906 png_sPLT_tp splt_palettes;
907 png_uint_32 splt_palettes_num;
908 #endif
909
910 #if defined(PNG_sCAL_SUPPORTED)
911 /* The sCAL chunk describes the actual physical dimensions of the
912 * subject matter of the graphic. The chunk contains a unit specification
913 * a byte value, and two ASCII strings representing floating-point
914 * values. The values are width and height corresponsing to one pixel
915 * in the image. This external representation is converted to double
916 * here. Data values are valid if (valid & PNG_INFO_sCAL) is non-zero.
917 */
918 png_byte scal_unit; /* unit of physical scale */
919 #ifdef PNG_FLOATING_POINT_SUPPORTED
920 double scal_pixel_width; /* width of one pixel */
921 double scal_pixel_height; /* height of one pixel */
922 #endif
923 #ifdef PNG_FIXED_POINT_SUPPORTED
924 png_charp scal_s_width; /* string containing height */
925 png_charp scal_s_height; /* string containing width */
926 #endif
927 #endif
928
929 #if defined(PNG_INFO_IMAGE_SUPPORTED)
930 /* Memory has been allocated if (valid & PNG_ALLOCATED_INFO_ROWS) non-zero */
931 /* Data valid if (valid & PNG_INFO_IDAT) non-zero */
932 png_bytepp row_pointers; /* the image bits */
933 #endif
934
935 #if defined(PNG_FIXED_POINT_SUPPORTED) && defined(PNG_gAMA_SUPPORTED)
936 png_fixed_point int_gamma; /* gamma of image, if (valid & PNG_INFO_gAMA) */
937 #endif
938
939 #if defined(PNG_cHRM_SUPPORTED) && defined(PNG_FIXED_POINT_SUPPORTED)
940 png_fixed_point int_x_white;
941 png_fixed_point int_y_white;
942 png_fixed_point int_x_red;
943 png_fixed_point int_y_red;
944 png_fixed_point int_x_green;
945 png_fixed_point int_y_green;
946 png_fixed_point int_x_blue;
947 png_fixed_point int_y_blue;
948 #endif
949
950 } png_info;
951
952 typedef png_info FAR * png_infop;
953 typedef png_info FAR * FAR * png_infopp;
954
955 /* Maximum positive integer used in PNG is (2^31)-1 */
956 #define PNG_UINT_31_MAX ((png_uint_32)0x7fffffffL)
957 #define PNG_UINT_32_MAX ((png_uint_32)(-1))
958 #define PNG_SIZE_MAX ((png_size_t)(-1))
959 #if defined(PNG_1_0_X) || defined (PNG_1_2_X)
960 /* PNG_MAX_UINT is deprecated; use PNG_UINT_31_MAX instead. */
961 #define PNG_MAX_UINT PNG_UINT_31_MAX
962 #endif
963
964 /* These describe the color_type field in png_info. */
965 /* color type masks */
966 #define PNG_COLOR_MASK_PALETTE 1
967 #define PNG_COLOR_MASK_COLOR 2
968 #define PNG_COLOR_MASK_ALPHA 4
969
970 /* color types. Note that not all combinations are legal */
971 #define PNG_COLOR_TYPE_GRAY 0
972 #define PNG_COLOR_TYPE_PALETTE (PNG_COLOR_MASK_COLOR | PNG_COLOR_MASK_PALETTE)
973 #define PNG_COLOR_TYPE_RGB (PNG_COLOR_MASK_COLOR)
974 #define PNG_COLOR_TYPE_RGB_ALPHA (PNG_COLOR_MASK_COLOR | PNG_COLOR_MASK_ALPHA)
975 #define PNG_COLOR_TYPE_GRAY_ALPHA (PNG_COLOR_MASK_ALPHA)
976 /* aliases */
977 #define PNG_COLOR_TYPE_RGBA PNG_COLOR_TYPE_RGB_ALPHA
978 #define PNG_COLOR_TYPE_GA PNG_COLOR_TYPE_GRAY_ALPHA
979
980 /* This is for compression type. PNG 1.0-1.2 only define the single type. */
981 #define PNG_COMPRESSION_TYPE_BASE 0 /* Deflate method 8, 32K window */
982 #define PNG_COMPRESSION_TYPE_DEFAULT PNG_COMPRESSION_TYPE_BASE
983
984 /* This is for filter type. PNG 1.0-1.2 only define the single type. */
985 #define PNG_FILTER_TYPE_BASE 0 /* Single row per-byte filtering */
986 #define PNG_INTRAPIXEL_DIFFERENCING 64 /* Used only in MNG datastreams */
987 #define PNG_FILTER_TYPE_DEFAULT PNG_FILTER_TYPE_BASE
988
989 /* These are for the interlacing type. These values should NOT be changed. */
990 #define PNG_INTERLACE_NONE 0 /* Non-interlaced image */
991 #define PNG_INTERLACE_ADAM7 1 /* Adam7 interlacing */
992 #define PNG_INTERLACE_LAST 2 /* Not a valid value */
993
994 /* These are for the oFFs chunk. These values should NOT be changed. */
995 #define PNG_OFFSET_PIXEL 0 /* Offset in pixels */
996 #define PNG_OFFSET_MICROMETER 1 /* Offset in micrometers (1/10^6 meter) */
997 #define PNG_OFFSET_LAST 2 /* Not a valid value */
998
999 /* These are for the pCAL chunk. These values should NOT be changed. */
1000 #define PNG_EQUATION_LINEAR 0 /* Linear transformation */
1001 #define PNG_EQUATION_BASE_E 1 /* Exponential base e transform */
1002 #define PNG_EQUATION_ARBITRARY 2 /* Arbitrary base exponential transform */
1003 #define PNG_EQUATION_HYPERBOLIC 3 /* Hyperbolic sine transformation */
1004 #define PNG_EQUATION_LAST 4 /* Not a valid value */
1005
1006 /* These are for the sCAL chunk. These values should NOT be changed. */
1007 #define PNG_SCALE_UNKNOWN 0 /* unknown unit (image scale) */
1008 #define PNG_SCALE_METER 1 /* meters per pixel */
1009 #define PNG_SCALE_RADIAN 2 /* radians per pixel */
1010 #define PNG_SCALE_LAST 3 /* Not a valid value */
1011
1012 /* These are for the pHYs chunk. These values should NOT be changed. */
1013 #define PNG_RESOLUTION_UNKNOWN 0 /* pixels/unknown unit (aspect ratio) */
1014 #define PNG_RESOLUTION_METER 1 /* pixels/meter */
1015 #define PNG_RESOLUTION_LAST 2 /* Not a valid value */
1016
1017 /* These are for the sRGB chunk. These values should NOT be changed. */
1018 #define PNG_sRGB_INTENT_PERCEPTUAL 0
1019 #define PNG_sRGB_INTENT_RELATIVE 1
1020 #define PNG_sRGB_INTENT_SATURATION 2
1021 #define PNG_sRGB_INTENT_ABSOLUTE 3
1022 #define PNG_sRGB_INTENT_LAST 4 /* Not a valid value */
1023
1024 /* This is for text chunks */
1025 #define PNG_KEYWORD_MAX_LENGTH 79
1026
1027 /* Maximum number of entries in PLTE/sPLT/tRNS arrays */
1028 #define PNG_MAX_PALETTE_LENGTH 256
1029
1030 /* These determine if an ancillary chunk's data has been successfully read
1031 * from the PNG header, or if the application has filled in the corresponding
1032 * data in the info_struct to be written into the output file. The values
1033 * of the PNG_INFO_<chunk> defines should NOT be changed.
1034 */
1035 #define PNG_INFO_gAMA 0x0001
1036 #define PNG_INFO_sBIT 0x0002
1037 #define PNG_INFO_cHRM 0x0004
1038 #define PNG_INFO_PLTE 0x0008
1039 #define PNG_INFO_tRNS 0x0010
1040 #define PNG_INFO_bKGD 0x0020
1041 #define PNG_INFO_hIST 0x0040
1042 #define PNG_INFO_pHYs 0x0080
1043 #define PNG_INFO_oFFs 0x0100
1044 #define PNG_INFO_tIME 0x0200
1045 #define PNG_INFO_pCAL 0x0400
1046 #define PNG_INFO_sRGB 0x0800 /* GR-P, 0.96a */
1047 #define PNG_INFO_iCCP 0x1000 /* ESR, 1.0.6 */
1048 #define PNG_INFO_sPLT 0x2000 /* ESR, 1.0.6 */
1049 #define PNG_INFO_sCAL 0x4000 /* ESR, 1.0.6 */
1050 #define PNG_INFO_IDAT 0x8000L /* ESR, 1.0.6 */
1051
1052 /* This is used for the transformation routines, as some of them
1053 * change these values for the row. It also should enable using
1054 * the routines for other purposes.
1055 */
1056 typedef struct png_row_info_struct
1057 {
1058 png_uint_32 width; /* width of row */
1059 png_uint_32 rowbytes; /* number of bytes in row */
1060 png_byte color_type; /* color type of row */
1061 png_byte bit_depth; /* bit depth of row */
1062 png_byte channels; /* number of channels (1, 2, 3, or 4) */
1063 png_byte pixel_depth; /* bits per pixel (depth * channels) */
1064 } png_row_info;
1065
1066 typedef png_row_info FAR * png_row_infop;
1067 typedef png_row_info FAR * FAR * png_row_infopp;
1068
1069 /* These are the function types for the I/O functions and for the functions
1070 * that allow the user to override the default I/O functions with his or her
1071 * own. The png_error_ptr type should match that of user-supplied warning
1072 * and error functions, while the png_rw_ptr type should match that of the
1073 * user read/write data functions.
1074 */
1075 typedef struct png_struct_def png_struct;
1076 typedef png_struct FAR * png_structp;
1077
1078 typedef void (PNGAPI *png_error_ptr) PNGARG((png_structp, png_const_charp));
1079 typedef void (PNGAPI *png_rw_ptr) PNGARG((png_structp, png_bytep, png_size_t));
1080 typedef void (PNGAPI *png_flush_ptr) PNGARG((png_structp));
1081 typedef void (PNGAPI *png_read_status_ptr) PNGARG((png_structp, png_uint_32,
1082 int));
1083 typedef void (PNGAPI *png_write_status_ptr) PNGARG((png_structp, png_uint_32,
1084 int));
1085
1086 #ifdef PNG_PROGRESSIVE_READ_SUPPORTED
1087 typedef void (PNGAPI *png_progressive_info_ptr) PNGARG((png_structp, png_infop));
1088 typedef void (PNGAPI *png_progressive_end_ptr) PNGARG((png_structp, png_infop));
1089 typedef void (PNGAPI *png_progressive_row_ptr) PNGARG((png_structp, png_bytep,
1090 png_uint_32, int));
1091 #endif
1092
1093 #if defined(PNG_READ_USER_TRANSFORM_SUPPORTED) || \
1094 defined(PNG_WRITE_USER_TRANSFORM_SUPPORTED) || \
1095 defined(PNG_LEGACY_SUPPORTED)
1096 typedef void (PNGAPI *png_user_transform_ptr) PNGARG((png_structp,
1097 png_row_infop, png_bytep));
1098 #endif
1099
1100 #if defined(PNG_USER_CHUNKS_SUPPORTED)
1101 typedef int (PNGAPI *png_user_chunk_ptr) PNGARG((png_structp, png_unknown_chunkp));
1102 #endif
1103 #if defined(PNG_UNKNOWN_CHUNKS_SUPPORTED)
1104 typedef void (PNGAPI *png_unknown_chunk_ptr) PNGARG((png_structp));
1105 #endif
1106
1107 /* Transform masks for the high-level interface */
1108 #define PNG_TRANSFORM_IDENTITY 0x0000 /* read and write */
1109 #define PNG_TRANSFORM_STRIP_16 0x0001 /* read only */
1110 #define PNG_TRANSFORM_STRIP_ALPHA 0x0002 /* read only */
1111 #define PNG_TRANSFORM_PACKING 0x0004 /* read and write */
1112 #define PNG_TRANSFORM_PACKSWAP 0x0008 /* read and write */
1113 #define PNG_TRANSFORM_EXPAND 0x0010 /* read only */
1114 #define PNG_TRANSFORM_INVERT_MONO 0x0020 /* read and write */
1115 #define PNG_TRANSFORM_SHIFT 0x0040 /* read and write */
1116 #define PNG_TRANSFORM_BGR 0x0080 /* read and write */
1117 #define PNG_TRANSFORM_SWAP_ALPHA 0x0100 /* read and write */
1118 #define PNG_TRANSFORM_SWAP_ENDIAN 0x0200 /* read and write */
1119 #define PNG_TRANSFORM_INVERT_ALPHA 0x0400 /* read and write */
1120 #define PNG_TRANSFORM_STRIP_FILLER 0x0800 /* WRITE only */
1121
1122 /* Flags for MNG supported features */
1123 #define PNG_FLAG_MNG_EMPTY_PLTE 0x01
1124 #define PNG_FLAG_MNG_FILTER_64 0x04
1125 #define PNG_ALL_MNG_FEATURES 0x05
1126
1127 typedef png_voidp (*png_malloc_ptr) PNGARG((png_structp, png_size_t));
1128 typedef void (*png_free_ptr) PNGARG((png_structp, png_voidp));
1129
1130 /* The structure that holds the information to read and write PNG files.
1131 * The only people who need to care about what is inside of this are the
1132 * people who will be modifying the library for their own special needs.
1133 * It should NOT be accessed directly by an application, except to store
1134 * the jmp_buf.
1135 */
1136
1137 struct png_struct_def
1138 {
1139 #ifdef PNG_SETJMP_SUPPORTED
1140 jmp_buf jmpbuf; /* used in png_error */
1141 #endif
1142 png_error_ptr error_fn; /* function for printing errors and aborting */
1143 png_error_ptr warning_fn; /* function for printing warnings */
1144 png_voidp error_ptr; /* user supplied struct for error functions */
1145 png_rw_ptr write_data_fn; /* function for writing output data */
1146 png_rw_ptr read_data_fn; /* function for reading input data */
1147 png_voidp io_ptr; /* ptr to application struct for I/O functions */
1148
1149 #if defined(PNG_READ_USER_TRANSFORM_SUPPORTED)
1150 png_user_transform_ptr read_user_transform_fn; /* user read transform */
1151 #endif
1152
1153 #if defined(PNG_WRITE_USER_TRANSFORM_SUPPORTED)
1154 png_user_transform_ptr write_user_transform_fn; /* user write transform */
1155 #endif
1156
1157 /* These were added in libpng-1.0.2 */
1158 #if defined(PNG_USER_TRANSFORM_PTR_SUPPORTED)
1159 #if defined(PNG_READ_USER_TRANSFORM_SUPPORTED) || \
1160 defined(PNG_WRITE_USER_TRANSFORM_SUPPORTED)
1161 png_voidp user_transform_ptr; /* user supplied struct for user transform */
1162 png_byte user_transform_depth; /* bit depth of user transformed pixels */
1163 png_byte user_transform_channels; /* channels in user transformed pixels */
1164 #endif
1165 #endif
1166
1167 png_uint_32 mode; /* tells us where we are in the PNG file */
1168 png_uint_32 flags; /* flags indicating various things to libpng */
1169 png_uint_32 transformations; /* which transformations to perform */
1170
1171 z_stream zstream; /* pointer to decompression structure (below) */
1172 png_bytep zbuf; /* buffer for zlib */
1173 png_size_t zbuf_size; /* size of zbuf */
1174 int zlib_level; /* holds zlib compression level */
1175 int zlib_method; /* holds zlib compression method */
1176 int zlib_window_bits; /* holds zlib compression window bits */
1177 int zlib_mem_level; /* holds zlib compression memory level */
1178 int zlib_strategy; /* holds zlib compression strategy */
1179
1180 png_uint_32 width; /* width of image in pixels */
1181 png_uint_32 height; /* height of image in pixels */
1182 png_uint_32 num_rows; /* number of rows in current pass */
1183 png_uint_32 usr_width; /* width of row at start of write */
1184 png_uint_32 rowbytes; /* size of row in bytes */
1185 png_uint_32 irowbytes; /* size of current interlaced row in bytes */
1186 png_uint_32 iwidth; /* width of current interlaced row in pixels */
1187 png_uint_32 row_number; /* current row in interlace pass */
1188 png_bytep prev_row; /* buffer to save previous (unfiltered) row */
1189 png_bytep row_buf; /* buffer to save current (unfiltered) row */
1190 #ifndef PNG_NO_WRITE_FILTERING
1191 png_bytep sub_row; /* buffer to save "sub" row when filtering */
1192 png_bytep up_row; /* buffer to save "up" row when filtering */
1193 png_bytep avg_row; /* buffer to save "avg" row when filtering */
1194 png_bytep paeth_row; /* buffer to save "Paeth" row when filtering */
1195 #endif
1196 png_row_info row_info; /* used for transformation routines */
1197
1198 png_uint_32 idat_size; /* current IDAT size for read */
1199 png_uint_32 crc; /* current chunk CRC value */
1200 png_colorp palette; /* palette from the input file */
1201 png_uint_16 num_palette; /* number of color entries in palette */
1202 png_uint_16 num_trans; /* number of transparency values */
1203 png_byte chunk_name[5]; /* null-terminated name of current chunk */
1204 png_byte compression; /* file compression type (always 0) */
1205 png_byte filter; /* file filter type (always 0) */
1206 png_byte interlaced; /* PNG_INTERLACE_NONE, PNG_INTERLACE_ADAM7 */
1207 png_byte pass; /* current interlace pass (0 - 6) */
1208 png_byte do_filter; /* row filter flags (see PNG_FILTER_ below ) */
1209 png_byte color_type; /* color type of file */
1210 png_byte bit_depth; /* bit depth of file */
1211 png_byte usr_bit_depth; /* bit depth of users row */
1212 png_byte pixel_depth; /* number of bits per pixel */
1213 png_byte channels; /* number of channels in file */
1214 png_byte usr_channels; /* channels at start of write */
1215 png_byte sig_bytes; /* magic bytes read/written from start of file */
1216
1217 #if defined(PNG_READ_FILLER_SUPPORTED) || defined(PNG_WRITE_FILLER_SUPPORTED)
1218 #ifdef PNG_LEGACY_SUPPORTED
1219 png_byte filler; /* filler byte for pixel expansion */
1220 #else
1221 png_uint_16 filler; /* filler bytes for pixel expansion */
1222 #endif
1223 #endif
1224
1225 #if defined(PNG_bKGD_SUPPORTED)
1226 png_byte background_gamma_type;
1227 # ifdef PNG_FLOATING_POINT_SUPPORTED
1228 float background_gamma;
1229 # endif
1230 png_color_16 background; /* background color in screen gamma space */
1231 #if defined(PNG_READ_GAMMA_SUPPORTED)
1232 png_color_16 background_1; /* background normalized to gamma 1.0 */
1233 #endif
1234 #endif /* PNG_bKGD_SUPPORTED */
1235
1236 #if defined(PNG_WRITE_FLUSH_SUPPORTED)
1237 png_flush_ptr output_flush_fn;/* Function for flushing output */
1238 png_uint_32 flush_dist; /* how many rows apart to flush, 0 - no flush */
1239 png_uint_32 flush_rows; /* number of rows written since last flush */
1240 #endif
1241
1242 #if defined(PNG_READ_GAMMA_SUPPORTED) || defined(PNG_READ_BACKGROUND_SUPPORTED)
1243 int gamma_shift; /* number of "insignificant" bits 16-bit gamma */
1244 #ifdef PNG_FLOATING_POINT_SUPPORTED
1245 float gamma; /* file gamma value */
1246 float screen_gamma; /* screen gamma value (display_exponent) */
1247 #endif
1248 #endif
1249
1250 #if defined(PNG_READ_GAMMA_SUPPORTED) || defined(PNG_READ_BACKGROUND_SUPPORTED)
1251 png_bytep gamma_table; /* gamma table for 8-bit depth files */
1252 png_bytep gamma_from_1; /* converts from 1.0 to screen */
1253 png_bytep gamma_to_1; /* converts from file to 1.0 */
1254 png_uint_16pp gamma_16_table; /* gamma table for 16-bit depth files */
1255 png_uint_16pp gamma_16_from_1; /* converts from 1.0 to screen */
1256 png_uint_16pp gamma_16_to_1; /* converts from file to 1.0 */
1257 #endif
1258
1259 #if defined(PNG_READ_GAMMA_SUPPORTED) || defined(PNG_sBIT_SUPPORTED)
1260 png_color_8 sig_bit; /* significant bits in each available channel */
1261 #endif
1262
1263 #if defined(PNG_READ_SHIFT_SUPPORTED) || defined(PNG_WRITE_SHIFT_SUPPORTED)
1264 png_color_8 shift; /* shift for significant bit tranformation */
1265 #endif
1266
1267 #if defined(PNG_tRNS_SUPPORTED) || defined(PNG_READ_BACKGROUND_SUPPORTED) \
1268 || defined(PNG_READ_EXPAND_SUPPORTED) || defined(PNG_READ_BACKGROUND_SUPPORTED)
1269 png_bytep trans; /* transparency values for paletted files */
1270 png_color_16 trans_values; /* transparency values for non-paletted files */
1271 #endif
1272
1273 png_read_status_ptr read_row_fn; /* called after each row is decoded */
1274 png_write_status_ptr write_row_fn; /* called after each row is encoded */
1275 #ifdef PNG_PROGRESSIVE_READ_SUPPORTED
1276 png_progressive_info_ptr info_fn; /* called after header data fully read */
1277 png_progressive_row_ptr row_fn; /* called after each prog. row is decoded */
1278 png_progressive_end_ptr end_fn; /* called after image is complete */
1279 png_bytep save_buffer_ptr; /* current location in save_buffer */
1280 png_bytep save_buffer; /* buffer for previously read data */
1281 png_bytep current_buffer_ptr; /* current location in current_buffer */
1282 png_bytep current_buffer; /* buffer for recently used data */
1283 png_uint_32 push_length; /* size of current input chunk */
1284 png_uint_32 skip_length; /* bytes to skip in input data */
1285 png_size_t save_buffer_size; /* amount of data now in save_buffer */
1286 png_size_t save_buffer_max; /* total size of save_buffer */
1287 png_size_t buffer_size; /* total amount of available input data */
1288 png_size_t current_buffer_size; /* amount of data now in current_buffer */
1289 int process_mode; /* what push library is currently doing */
1290 int cur_palette; /* current push library palette index */
1291
1292 # if defined(PNG_TEXT_SUPPORTED)
1293 png_size_t current_text_size; /* current size of text input data */
1294 png_size_t current_text_left; /* how much text left to read in input */
1295 png_charp current_text; /* current text chunk buffer */
1296 png_charp current_text_ptr; /* current location in current_text */
1297 # endif /* PNG_TEXT_SUPPORTED */
1298 #endif /* PNG_PROGRESSIVE_READ_SUPPORTED */
1299
1300 #if defined(__TURBOC__) && !defined(_Windows) && !defined(__FLAT__)
1301 /* for the Borland special 64K segment handler */
1302 png_bytepp offset_table_ptr;
1303 png_bytep offset_table;
1304 png_uint_16 offset_table_number;
1305 png_uint_16 offset_table_count;
1306 png_uint_16 offset_table_count_free;
1307 #endif
1308
1309 #if defined(PNG_READ_DITHER_SUPPORTED)
1310 png_bytep palette_lookup; /* lookup table for dithering */
1311 png_bytep dither_index; /* index translation for palette files */
1312 #endif
1313
1314 #if defined(PNG_READ_DITHER_SUPPORTED) || defined(PNG_hIST_SUPPORTED)
1315 png_uint_16p hist; /* histogram */
1316 #endif
1317
1318 #if defined(PNG_WRITE_WEIGHTED_FILTER_SUPPORTED)
1319 png_byte heuristic_method; /* heuristic for row filter selection */
1320 png_byte num_prev_filters; /* number of weights for previous rows */
1321 png_bytep prev_filters; /* filter type(s) of previous row(s) */
1322 png_uint_16p filter_weights; /* weight(s) for previous line(s) */
1323 png_uint_16p inv_filter_weights; /* 1/weight(s) for previous line(s) */
1324 png_uint_16p filter_costs; /* relative filter calculation cost */
1325 png_uint_16p inv_filter_costs; /* 1/relative filter calculation cost */
1326 #endif
1327
1328 #if defined(PNG_TIME_RFC1123_SUPPORTED)
1329 png_charp time_buffer; /* String to hold RFC 1123 time text */
1330 #endif
1331
1332 /* New members added in libpng-1.0.6 */
1333
1334 #ifdef PNG_FREE_ME_SUPPORTED
1335 png_uint_32 free_me; /* flags items libpng is responsible for freeing */
1336 #endif
1337
1338 #if defined(PNG_USER_CHUNKS_SUPPORTED)
1339 png_voidp user_chunk_ptr;
1340 png_user_chunk_ptr read_user_chunk_fn; /* user read chunk handler */
1341 #endif
1342
1343 #if defined(PNG_UNKNOWN_CHUNKS_SUPPORTED)
1344 int num_chunk_list;
1345 png_bytep chunk_list;
1346 #endif
1347
1348 /* New members added in libpng-1.0.3 */
1349 #if defined(PNG_READ_RGB_TO_GRAY_SUPPORTED)
1350 png_byte rgb_to_gray_status;
1351 /* These were changed from png_byte in libpng-1.0.6 */
1352 png_uint_16 rgb_to_gray_red_coeff;
1353 png_uint_16 rgb_to_gray_green_coeff;
1354 png_uint_16 rgb_to_gray_blue_coeff;
1355 #endif
1356
1357 /* New member added in libpng-1.0.4 (renamed in 1.0.9) */
1358 #if defined(PNG_MNG_FEATURES_SUPPORTED) || \
1359 defined(PNG_READ_EMPTY_PLTE_SUPPORTED) || \
1360 defined(PNG_WRITE_EMPTY_PLTE_SUPPORTED)
1361 /* changed from png_byte to png_uint_32 at version 1.2.0 */
1362 #ifdef PNG_1_0_X
1363 png_byte mng_features_permitted;
1364 #else
1365 png_uint_32 mng_features_permitted;
1366 #endif /* PNG_1_0_X */
1367 #endif
1368
1369 /* New member added in libpng-1.0.7 */
1370 #if defined(PNG_READ_GAMMA_SUPPORTED) || defined(PNG_READ_BACKGROUND_SUPPORTED)
1371 png_fixed_point int_gamma;
1372 #endif
1373
1374 /* New member added in libpng-1.0.9, ifdef'ed out in 1.0.12, enabled in 1.2.0 */
1375 #if defined(PNG_MNG_FEATURES_SUPPORTED)
1376 png_byte filter_type;
1377 #endif
1378
1379 #if defined(PNG_1_0_X)
1380 /* New member added in libpng-1.0.10, ifdef'ed out in 1.2.0 */
1381 png_uint_32 row_buf_size;
1382 #endif
1383
1384 /* New members added in libpng-1.2.0 */
1385 #if defined(PNG_ASSEMBLER_CODE_SUPPORTED)
1386 # if !defined(PNG_1_0_X)
1387 # if defined(PNG_MMX_CODE_SUPPORTED)
1388 png_byte mmx_bitdepth_threshold;
1389 png_uint_32 mmx_rowbytes_threshold;
1390 # endif
1391 png_uint_32 asm_flags;
1392 # endif
1393 #endif
1394
1395 /* New members added in libpng-1.0.2 but first enabled by default in 1.2.0 */
1396 #ifdef PNG_USER_MEM_SUPPORTED
1397 png_voidp mem_ptr; /* user supplied struct for mem functions */
1398 png_malloc_ptr malloc_fn; /* function for allocating memory */
1399 png_free_ptr free_fn; /* function for freeing memory */
1400 #endif
1401
1402 /* New member added in libpng-1.0.13 and 1.2.0 */
1403 png_bytep big_row_buf; /* buffer to save current (unfiltered) row */
1404
1405 #if defined(PNG_READ_DITHER_SUPPORTED)
1406 /* The following three members were added at version 1.0.14 and 1.2.4 */
1407 png_bytep dither_sort; /* working sort array */
1408 png_bytep index_to_palette; /* where the original index currently is */
1409 /* in the palette */
1410 png_bytep palette_to_index; /* which original index points to this */
1411 /* palette color */
1412 #endif
1413
1414 /* New members added in libpng-1.0.16 and 1.2.6 */
1415 png_byte compression_type;
1416
1417 #ifdef PNG_SET_USER_LIMITS_SUPPORTED
1418 png_uint_32 user_width_max;
1419 png_uint_32 user_height_max;
1420 #endif
1421
1422 /* New member added in libpng-1.0.25 and 1.2.17 */
1423 #if defined(PNG_UNKNOWN_CHUNKS_SUPPORTED)
1424 /* storage for unknown chunk that the library doesn't recognize. */
1425 png_unknown_chunk unknown_chunk;
1426 #endif
1427 };
1428
1429
1430 /* This triggers a compiler error in png.c, if png.c and png.h
1431 * do not agree upon the version number.
1432 */
1433 typedef png_structp version_1_2_24;
1434
1435 typedef png_struct FAR * FAR * png_structpp;
1436
1437 /* Here are the function definitions most commonly used. This is not
1438 * the place to find out how to use libpng. See libpng.txt for the
1439 * full explanation, see example.c for the summary. This just provides
1440 * a simple one line description of the use of each function.
1441 */
1442
1443 /* Returns the version number of the library */
1444 extern PNG_EXPORT(png_uint_32,png_access_version_number) PNGARG((void));
1445
1446 /* Tell lib we have already handled the first <num_bytes> magic bytes.
1447 * Handling more than 8 bytes from the beginning of the file is an error.
1448 */
1449 extern PNG_EXPORT(void,png_set_sig_bytes) PNGARG((png_structp png_ptr,
1450 int num_bytes));
1451
1452 /* Check sig[start] through sig[start + num_to_check - 1] to see if it's a
1453 * PNG file. Returns zero if the supplied bytes match the 8-byte PNG
1454 * signature, and non-zero otherwise. Having num_to_check == 0 or
1455 * start > 7 will always fail (ie return non-zero).
1456 */
1457 extern PNG_EXPORT(int,png_sig_cmp) PNGARG((png_bytep sig, png_size_t start,
1458 png_size_t num_to_check));
1459
1460 /* Simple signature checking function. This is the same as calling
1461 * png_check_sig(sig, n) := !png_sig_cmp(sig, 0, n).
1462 */
1463 extern PNG_EXPORT(int,png_check_sig) PNGARG((png_bytep sig, int num));
1464
1465 /* Allocate and initialize png_ptr struct for reading, and any other memory. */
1466 extern PNG_EXPORT(png_structp,png_create_read_struct)
1467 PNGARG((png_const_charp user_png_ver, png_voidp error_ptr,
1468 png_error_ptr error_fn, png_error_ptr warn_fn));
1469
1470 /* Allocate and initialize png_ptr struct for writing, and any other memory */
1471 extern PNG_EXPORT(png_structp,png_create_write_struct)
1472 PNGARG((png_const_charp user_png_ver, png_voidp error_ptr,
1473 png_error_ptr error_fn, png_error_ptr warn_fn));
1474
1475 #ifdef PNG_WRITE_SUPPORTED
1476 extern PNG_EXPORT(png_uint_32,png_get_compression_buffer_size)
1477 PNGARG((png_structp png_ptr));
1478 #endif
1479
1480 #ifdef PNG_WRITE_SUPPORTED
1481 extern PNG_EXPORT(void,png_set_compression_buffer_size)
1482 PNGARG((png_structp png_ptr, png_uint_32 size));
1483 #endif
1484
1485 /* Reset the compression stream */
1486 extern PNG_EXPORT(int,png_reset_zstream) PNGARG((png_structp png_ptr));
1487
1488 /* New functions added in libpng-1.0.2 (not enabled by default until 1.2.0) */
1489 #ifdef PNG_USER_MEM_SUPPORTED
1490 extern PNG_EXPORT(png_structp,png_create_read_struct_2)
1491 PNGARG((png_const_charp user_png_ver, png_voidp error_ptr,
1492 png_error_ptr error_fn, png_error_ptr warn_fn, png_voidp mem_ptr,
1493 png_malloc_ptr malloc_fn, png_free_ptr free_fn));
1494 extern PNG_EXPORT(png_structp,png_create_write_struct_2)
1495 PNGARG((png_const_charp user_png_ver, png_voidp error_ptr,
1496 png_error_ptr error_fn, png_error_ptr warn_fn, png_voidp mem_ptr,
1497 png_malloc_ptr malloc_fn, png_free_ptr free_fn));
1498 #endif
1499
1500 /* Write a PNG chunk - size, type, (optional) data, CRC. */
1501 extern PNG_EXPORT(void,png_write_chunk) PNGARG((png_structp png_ptr,
1502 png_bytep chunk_name, png_bytep data, png_size_t length));
1503
1504 /* Write the start of a PNG chunk - length and chunk name. */
1505 extern PNG_EXPORT(void,png_write_chunk_start) PNGARG((png_structp png_ptr,
1506 png_bytep chunk_name, png_uint_32 length));
1507
1508 /* Write the data of a PNG chunk started with png_write_chunk_start(). */
1509 extern PNG_EXPORT(void,png_write_chunk_data) PNGARG((png_structp png_ptr,
1510 png_bytep data, png_size_t length));
1511
1512 /* Finish a chunk started with png_write_chunk_start() (includes CRC). */
1513 extern PNG_EXPORT(void,png_write_chunk_end) PNGARG((png_structp png_ptr));
1514
1515 /* Allocate and initialize the info structure */
1516 extern PNG_EXPORT(png_infop,png_create_info_struct)
1517 PNGARG((png_structp png_ptr));
1518
1519 #if defined(PNG_1_0_X) || defined (PNG_1_2_X)
1520 /* Initialize the info structure (old interface - DEPRECATED) */
1521 extern PNG_EXPORT(void,png_info_init) PNGARG((png_infop info_ptr));
1522 #undef png_info_init
1523 #define png_info_init(info_ptr) png_info_init_3(&info_ptr,\
1524 png_sizeof(png_info));
1525 #endif
1526
1527 extern PNG_EXPORT(void,png_info_init_3) PNGARG((png_infopp info_ptr,
1528 png_size_t png_info_struct_size));
1529
1530 /* Writes all the PNG information before the image. */
1531 extern PNG_EXPORT(void,png_write_info_before_PLTE) PNGARG((png_structp png_ptr,
1532 png_infop info_ptr));
1533 extern PNG_EXPORT(void,png_write_info) PNGARG((png_structp png_ptr,
1534 png_infop info_ptr));
1535
1536 #ifndef PNG_NO_SEQUENTIAL_READ_SUPPORTED
1537 /* read the information before the actual image data. */
1538 extern PNG_EXPORT(void,png_read_info) PNGARG((png_structp png_ptr,
1539 png_infop info_ptr));
1540 #endif
1541
1542 #if defined(PNG_TIME_RFC1123_SUPPORTED)
1543 extern PNG_EXPORT(png_charp,png_convert_to_rfc1123)
1544 PNGARG((png_structp png_ptr, png_timep ptime));
1545 #endif
1546
1547 #if !defined(_WIN32_WCE)
1548 /* "time.h" functions are not supported on WindowsCE */
1549 #if defined(PNG_WRITE_tIME_SUPPORTED)
1550 /* convert from a struct tm to png_time */
1551 extern PNG_EXPORT(void,png_convert_from_struct_tm) PNGARG((png_timep ptime,
1552 struct tm FAR * ttime));
1553
1554 /* convert from time_t to png_time. Uses gmtime() */
1555 extern PNG_EXPORT(void,png_convert_from_time_t) PNGARG((png_timep ptime,
1556 time_t ttime));
1557 #endif /* PNG_WRITE_tIME_SUPPORTED */
1558 #endif /* _WIN32_WCE */
1559
1560 #if defined(PNG_READ_EXPAND_SUPPORTED)
1561 /* Expand data to 24-bit RGB, or 8-bit grayscale, with alpha if available. */
1562 extern PNG_EXPORT(void,png_set_expand) PNGARG((png_structp png_ptr));
1563 #if !defined(PNG_1_0_X)
1564 extern PNG_EXPORT(void,png_set_expand_gray_1_2_4_to_8) PNGARG((png_structp
1565 png_ptr));
1566 #endif
1567 extern PNG_EXPORT(void,png_set_palette_to_rgb) PNGARG((png_structp png_ptr));
1568 extern PNG_EXPORT(void,png_set_tRNS_to_alpha) PNGARG((png_structp png_ptr));
1569 #if defined(PNG_1_0_X) || defined (PNG_1_2_X)
1570 /* Deprecated */
1571 extern PNG_EXPORT(void,png_set_gray_1_2_4_to_8) PNGARG((png_structp png_ptr));
1572 #endif
1573 #endif
1574
1575 #if defined(PNG_READ_BGR_SUPPORTED) || defined(PNG_WRITE_BGR_SUPPORTED)
1576 /* Use blue, green, red order for pixels. */
1577 extern PNG_EXPORT(void,png_set_bgr) PNGARG((png_structp png_ptr));
1578 #endif
1579
1580 #if defined(PNG_READ_GRAY_TO_RGB_SUPPORTED)
1581 /* Expand the grayscale to 24-bit RGB if necessary. */
1582 extern PNG_EXPORT(void,png_set_gray_to_rgb) PNGARG((png_structp png_ptr));
1583 #endif
1584
1585 #if defined(PNG_READ_RGB_TO_GRAY_SUPPORTED)
1586 /* Reduce RGB to grayscale. */
1587 #ifdef PNG_FLOATING_POINT_SUPPORTED
1588 extern PNG_EXPORT(void,png_set_rgb_to_gray) PNGARG((png_structp png_ptr,
1589 int error_action, double red, double green ));
1590 #endif
1591 extern PNG_EXPORT(void,png_set_rgb_to_gray_fixed) PNGARG((png_structp png_ptr,
1592 int error_action, png_fixed_point red, png_fixed_point green ));
1593 extern PNG_EXPORT(png_byte,png_get_rgb_to_gray_status) PNGARG((png_structp
1594 png_ptr));
1595 #endif
1596
1597 extern PNG_EXPORT(void,png_build_grayscale_palette) PNGARG((int bit_depth,
1598 png_colorp palette));
1599
1600 #if defined(PNG_READ_STRIP_ALPHA_SUPPORTED)
1601 extern PNG_EXPORT(void,png_set_strip_alpha) PNGARG((png_structp png_ptr));
1602 #endif
1603
1604 #if defined(PNG_READ_SWAP_ALPHA_SUPPORTED) || \
1605 defined(PNG_WRITE_SWAP_ALPHA_SUPPORTED)
1606 extern PNG_EXPORT(void,png_set_swap_alpha) PNGARG((png_structp png_ptr));
1607 #endif
1608
1609 #if defined(PNG_READ_INVERT_ALPHA_SUPPORTED) || \
1610 defined(PNG_WRITE_INVERT_ALPHA_SUPPORTED)
1611 extern PNG_EXPORT(void,png_set_invert_alpha) PNGARG((png_structp png_ptr));
1612 #endif
1613
1614 #if defined(PNG_READ_FILLER_SUPPORTED) || defined(PNG_WRITE_FILLER_SUPPORTED)
1615 /* Add a filler byte to 8-bit Gray or 24-bit RGB images. */
1616 extern PNG_EXPORT(void,png_set_filler) PNGARG((png_structp png_ptr,
1617 png_uint_32 filler, int flags));
1618 /* The values of the PNG_FILLER_ defines should NOT be changed */
1619 #define PNG_FILLER_BEFORE 0
1620 #define PNG_FILLER_AFTER 1
1621 /* Add an alpha byte to 8-bit Gray or 24-bit RGB images. */
1622 #if !defined(PNG_1_0_X)
1623 extern PNG_EXPORT(void,png_set_add_alpha) PNGARG((png_structp png_ptr,
1624 png_uint_32 filler, int flags));
1625 #endif
1626 #endif /* PNG_READ_FILLER_SUPPORTED || PNG_WRITE_FILLER_SUPPORTED */
1627
1628 #if defined(PNG_READ_SWAP_SUPPORTED) || defined(PNG_WRITE_SWAP_SUPPORTED)
1629 /* Swap bytes in 16-bit depth files. */
1630 extern PNG_EXPORT(void,png_set_swap) PNGARG((png_structp png_ptr));
1631 #endif
1632
1633 #if defined(PNG_READ_PACK_SUPPORTED) || defined(PNG_WRITE_PACK_SUPPORTED)
1634 /* Use 1 byte per pixel in 1, 2, or 4-bit depth files. */
1635 extern PNG_EXPORT(void,png_set_packing) PNGARG((png_structp png_ptr));
1636 #endif
1637
1638 #if defined(PNG_READ_PACKSWAP_SUPPORTED) || defined(PNG_WRITE_PACKSWAP_SUPPORTED)
1639 /* Swap packing order of pixels in bytes. */
1640 extern PNG_EXPORT(void,png_set_packswap) PNGARG((png_structp png_ptr));
1641 #endif
1642
1643 #if defined(PNG_READ_SHIFT_SUPPORTED) || defined(PNG_WRITE_SHIFT_SUPPORTED)
1644 /* Converts files to legal bit depths. */
1645 extern PNG_EXPORT(void,png_set_shift) PNGARG((png_structp png_ptr,
1646 png_color_8p true_bits));
1647 #endif
1648
1649 #if defined(PNG_READ_INTERLACING_SUPPORTED) || \
1650 defined(PNG_WRITE_INTERLACING_SUPPORTED)
1651 /* Have the code handle the interlacing. Returns the number of passes. */
1652 extern PNG_EXPORT(int,png_set_interlace_handling) PNGARG((png_structp png_ptr));
1653 #endif
1654
1655 #if defined(PNG_READ_INVERT_SUPPORTED) || defined(PNG_WRITE_INVERT_SUPPORTED)
1656 /* Invert monochrome files */
1657 extern PNG_EXPORT(void,png_set_invert_mono) PNGARG((png_structp png_ptr));
1658 #endif
1659
1660 #if defined(PNG_READ_BACKGROUND_SUPPORTED)
1661 /* Handle alpha and tRNS by replacing with a background color. */
1662 #ifdef PNG_FLOATING_POINT_SUPPORTED
1663 extern PNG_EXPORT(void,png_set_background) PNGARG((png_structp png_ptr,
1664 png_color_16p background_color, int background_gamma_code,
1665 int need_expand, double background_gamma));
1666 #endif
1667 #define PNG_BACKGROUND_GAMMA_UNKNOWN 0
1668 #define PNG_BACKGROUND_GAMMA_SCREEN 1
1669 #define PNG_BACKGROUND_GAMMA_FILE 2
1670 #define PNG_BACKGROUND_GAMMA_UNIQUE 3
1671 #endif
1672
1673 #if defined(PNG_READ_16_TO_8_SUPPORTED)
1674 /* strip the second byte of information from a 16-bit depth file. */
1675 extern PNG_EXPORT(void,png_set_strip_16) PNGARG((png_structp png_ptr));
1676 #endif
1677
1678 #if defined(PNG_READ_DITHER_SUPPORTED)
1679 /* Turn on dithering, and reduce the palette to the number of colors available. */
1680 extern PNG_EXPORT(void,png_set_dither) PNGARG((png_structp png_ptr,
1681 png_colorp palette, int num_palette, int maximum_colors,
1682 png_uint_16p histogram, int full_dither));
1683 #endif
1684
1685 #if defined(PNG_READ_GAMMA_SUPPORTED)
1686 /* Handle gamma correction. Screen_gamma=(display_exponent) */
1687 #ifdef PNG_FLOATING_POINT_SUPPORTED
1688 extern PNG_EXPORT(void,png_set_gamma) PNGARG((png_structp png_ptr,
1689 double screen_gamma, double default_file_gamma));
1690 #endif
1691 #endif
1692
1693 #if defined(PNG_1_0_X) || defined (PNG_1_2_X)
1694 #if defined(PNG_READ_EMPTY_PLTE_SUPPORTED) || \
1695 defined(PNG_WRITE_EMPTY_PLTE_SUPPORTED)
1696 /* Permit or disallow empty PLTE (0: not permitted, 1: permitted) */
1697 /* Deprecated and will be removed. Use png_permit_mng_features() instead. */
1698 extern PNG_EXPORT(void,png_permit_empty_plte) PNGARG((png_structp png_ptr,
1699 int empty_plte_permitted));
1700 #endif
1701 #endif
1702
1703 #if defined(PNG_WRITE_FLUSH_SUPPORTED)
1704 /* Set how many lines between output flushes - 0 for no flushing */
1705 extern PNG_EXPORT(void,png_set_flush) PNGARG((png_structp png_ptr, int nrows));
1706 /* Flush the current PNG output buffer */
1707 extern PNG_EXPORT(void,png_write_flush) PNGARG((png_structp png_ptr));
1708 #endif
1709
1710 /* optional update palette with requested transformations */
1711 extern PNG_EXPORT(void,png_start_read_image) PNGARG((png_structp png_ptr));
1712
1713 /* optional call to update the users info structure */
1714 extern PNG_EXPORT(void,png_read_update_info) PNGARG((png_structp png_ptr,
1715 png_infop info_ptr));
1716
1717 #ifndef PNG_NO_SEQUENTIAL_READ_SUPPORTED
1718 /* read one or more rows of image data. */
1719 extern PNG_EXPORT(void,png_read_rows) PNGARG((png_structp png_ptr,
1720 png_bytepp row, png_bytepp display_row, png_uint_32 num_rows));
1721 #endif
1722
1723 #ifndef PNG_NO_SEQUENTIAL_READ_SUPPORTED
1724 /* read a row of data. */
1725 extern PNG_EXPORT(void,png_read_row) PNGARG((png_structp png_ptr,
1726 png_bytep row,
1727 png_bytep display_row));
1728 #endif
1729
1730 #ifndef PNG_NO_SEQUENTIAL_READ_SUPPORTED
1731 /* read the whole image into memory at once. */
1732 extern PNG_EXPORT(void,png_read_image) PNGARG((png_structp png_ptr,
1733 png_bytepp image));
1734 #endif
1735
1736 /* write a row of image data */
1737 extern PNG_EXPORT(void,png_write_row) PNGARG((png_structp png_ptr,
1738 png_bytep row));
1739
1740 /* write a few rows of image data */
1741 extern PNG_EXPORT(void,png_write_rows) PNGARG((png_structp png_ptr,
1742 png_bytepp row, png_uint_32 num_rows));
1743
1744 /* write the image data */
1745 extern PNG_EXPORT(void,png_write_image) PNGARG((png_structp png_ptr,
1746 png_bytepp image));
1747
1748 /* writes the end of the PNG file. */
1749 extern PNG_EXPORT(void,png_write_end) PNGARG((png_structp png_ptr,
1750 png_infop info_ptr));
1751
1752 #ifndef PNG_NO_SEQUENTIAL_READ_SUPPORTED
1753 /* read the end of the PNG file. */
1754 extern PNG_EXPORT(void,png_read_end) PNGARG((png_structp png_ptr,
1755 png_infop info_ptr));
1756 #endif
1757
1758 /* free any memory associated with the png_info_struct */
1759 extern PNG_EXPORT(void,png_destroy_info_struct) PNGARG((png_structp png_ptr,
1760 png_infopp info_ptr_ptr));
1761
1762 /* free any memory associated with the png_struct and the png_info_structs */
1763 extern PNG_EXPORT(void,png_destroy_read_struct) PNGARG((png_structpp
1764 png_ptr_ptr, png_infopp info_ptr_ptr, png_infopp end_info_ptr_ptr));
1765
1766 /* free all memory used by the read (old method - NOT DLL EXPORTED) */
1767 extern void png_read_destroy PNGARG((png_structp png_ptr, png_infop info_ptr,
1768 png_infop end_info_ptr));
1769
1770 /* free any memory associated with the png_struct and the png_info_structs */
1771 extern PNG_EXPORT(void,png_destroy_write_struct)
1772 PNGARG((png_structpp png_ptr_ptr, png_infopp info_ptr_ptr));
1773
1774 /* free any memory used in png_ptr struct (old method - NOT DLL EXPORTED) */
1775 extern void png_write_destroy PNGARG((png_structp png_ptr));
1776
1777 /* set the libpng method of handling chunk CRC errors */
1778 extern PNG_EXPORT(void,png_set_crc_action) PNGARG((png_structp png_ptr,
1779 int crit_action, int ancil_action));
1780
1781 /* Values for png_set_crc_action() to say how to handle CRC errors in
1782 * ancillary and critical chunks, and whether to use the data contained
1783 * therein. Note that it is impossible to "discard" data in a critical
1784 * chunk. For versions prior to 0.90, the action was always error/quit,
1785 * whereas in version 0.90 and later, the action for CRC errors in ancillary
1786 * chunks is warn/discard. These values should NOT be changed.
1787 *
1788 * value action:critical action:ancillary
1789 */
1790 #define PNG_CRC_DEFAULT 0 /* error/quit warn/discard data */
1791 #define PNG_CRC_ERROR_QUIT 1 /* error/quit error/quit */
1792 #define PNG_CRC_WARN_DISCARD 2 /* (INVALID) warn/discard data */
1793 #define PNG_CRC_WARN_USE 3 /* warn/use data warn/use data */
1794 #define PNG_CRC_QUIET_USE 4 /* quiet/use data quiet/use data */
1795 #define PNG_CRC_NO_CHANGE 5 /* use current value use current value */
1796
1797 /* These functions give the user control over the scan-line filtering in
1798 * libpng and the compression methods used by zlib. These functions are
1799 * mainly useful for testing, as the defaults should work with most users.
1800 * Those users who are tight on memory or want faster performance at the
1801 * expense of compression can modify them. See the compression library
1802 * header file (zlib.h) for an explination of the compression functions.
1803 */
1804
1805 /* set the filtering method(s) used by libpng. Currently, the only valid
1806 * value for "method" is 0.
1807 */
1808 extern PNG_EXPORT(void,png_set_filter) PNGARG((png_structp png_ptr, int method,
1809 int filters));
1810
1811 /* Flags for png_set_filter() to say which filters to use. The flags
1812 * are chosen so that they don't conflict with real filter types
1813 * below, in case they are supplied instead of the #defined constants.
1814 * These values should NOT be changed.
1815 */
1816 #define PNG_NO_FILTERS 0x00
1817 #define PNG_FILTER_NONE 0x08
1818 #define PNG_FILTER_SUB 0x10
1819 #define PNG_FILTER_UP 0x20
1820 #define PNG_FILTER_AVG 0x40
1821 #define PNG_FILTER_PAETH 0x80
1822 #define PNG_ALL_FILTERS (PNG_FILTER_NONE | PNG_FILTER_SUB | PNG_FILTER_UP | \
1823 PNG_FILTER_AVG | PNG_FILTER_PAETH)
1824
1825 /* Filter values (not flags) - used in pngwrite.c, pngwutil.c for now.
1826 * These defines should NOT be changed.
1827 */
1828 #define PNG_FILTER_VALUE_NONE 0
1829 #define PNG_FILTER_VALUE_SUB 1
1830 #define PNG_FILTER_VALUE_UP 2
1831 #define PNG_FILTER_VALUE_AVG 3
1832 #define PNG_FILTER_VALUE_PAETH 4
1833 #define PNG_FILTER_VALUE_LAST 5
1834
1835 #if defined(PNG_WRITE_WEIGHTED_FILTER_SUPPORTED) /* EXPERIMENTAL */
1836 /* The "heuristic_method" is given by one of the PNG_FILTER_HEURISTIC_
1837 * defines, either the default (minimum-sum-of-absolute-differences), or
1838 * the experimental method (weighted-minimum-sum-of-absolute-differences).
1839 *
1840 * Weights are factors >= 1.0, indicating how important it is to keep the
1841 * filter type consistent between rows. Larger numbers mean the current
1842 * filter is that many times as likely to be the same as the "num_weights"
1843 * previous filters. This is cumulative for each previous row with a weight.
1844 * There needs to be "num_weights" values in "filter_weights", or it can be
1845 * NULL if the weights aren't being specified. Weights have no influence on
1846 * the selection of the first row filter. Well chosen weights can (in theory)
1847 * improve the compression for a given image.
1848 *
1849 * Costs are factors >= 1.0 indicating the relative decoding costs of a
1850 * filter type. Higher costs indicate more decoding expense, and are
1851 * therefore less likely to be selected over a filter with lower computational
1852 * costs. There needs to be a value in "filter_costs" for each valid filter
1853 * type (given by PNG_FILTER_VALUE_LAST), or it can be NULL if you aren't
1854 * setting the costs. Costs try to improve the speed of decompression without
1855 * unduly increasing the compressed image size.
1856 *
1857 * A negative weight or cost indicates the default value is to be used, and
1858 * values in the range [0.0, 1.0) indicate the value is to remain unchanged.
1859 * The default values for both weights and costs are currently 1.0, but may
1860 * change if good general weighting/cost heuristics can be found. If both
1861 * the weights and costs are set to 1.0, this degenerates the WEIGHTED method
1862 * to the UNWEIGHTED method, but with added encoding time/computation.
1863 */
1864 #ifdef PNG_FLOATING_POINT_SUPPORTED
1865 extern PNG_EXPORT(void,png_set_filter_heuristics) PNGARG((png_structp png_ptr,
1866 int heuristic_method, int num_weights, png_doublep filter_weights,
1867 png_doublep filter_costs));
1868 #endif
1869 #endif /* PNG_WRITE_WEIGHTED_FILTER_SUPPORTED */
1870
1871 /* Heuristic used for row filter selection. These defines should NOT be
1872 * changed.
1873 */
1874 #define PNG_FILTER_HEURISTIC_DEFAULT 0 /* Currently "UNWEIGHTED" */
1875 #define PNG_FILTER_HEURISTIC_UNWEIGHTED 1 /* Used by libpng < 0.95 */
1876 #define PNG_FILTER_HEURISTIC_WEIGHTED 2 /* Experimental feature */
1877 #define PNG_FILTER_HEURISTIC_LAST 3 /* Not a valid value */
1878
1879 /* Set the library compression level. Currently, valid values range from
1880 * 0 - 9, corresponding directly to the zlib compression levels 0 - 9
1881 * (0 - no compression, 9 - "maximal" compression). Note that tests have
1882 * shown that zlib compression levels 3-6 usually perform as well as level 9
1883 * for PNG images, and do considerably fewer caclulations. In the future,
1884 * these values may not correspond directly to the zlib compression levels.
1885 */
1886 extern PNG_EXPORT(void,png_set_compression_level) PNGARG((png_structp png_ptr,
1887 int level));
1888
1889 extern PNG_EXPORT(void,png_set_compression_mem_level)
1890 PNGARG((png_structp png_ptr, int mem_level));
1891
1892 extern PNG_EXPORT(void,png_set_compression_strategy)
1893 PNGARG((png_structp png_ptr, int strategy));
1894
1895 extern PNG_EXPORT(void,png_set_compression_window_bits)
1896 PNGARG((png_structp png_ptr, int window_bits));
1897
1898 extern PNG_EXPORT(void,png_set_compression_method) PNGARG((png_structp png_ptr,
1899 int method));
1900
1901 /* These next functions are called for input/output, memory, and error
1902 * handling. They are in the file pngrio.c, pngwio.c, and pngerror.c,
1903 * and call standard C I/O routines such as fread(), fwrite(), and
1904 * fprintf(). These functions can be made to use other I/O routines
1905 * at run time for those applications that need to handle I/O in a
1906 * different manner by calling png_set_???_fn(). See libpng.txt for
1907 * more information.
1908 */
1909
1910 #if !defined(PNG_NO_STDIO)
1911 /* Initialize the input/output for the PNG file to the default functions. */
1912 extern PNG_EXPORT(void,png_init_io) PNGARG((png_structp png_ptr, png_FILE_p fp));
1913 #endif
1914
1915 /* Replace the (error and abort), and warning functions with user
1916 * supplied functions. If no messages are to be printed you must still
1917 * write and use replacement functions. The replacement error_fn should
1918 * still do a longjmp to the last setjmp location if you are using this
1919 * method of error handling. If error_fn or warning_fn is NULL, the
1920 * default function will be used.
1921 */
1922
1923 extern PNG_EXPORT(void,png_set_error_fn) PNGARG((png_structp png_ptr,
1924 png_voidp error_ptr, png_error_ptr error_fn, png_error_ptr warning_fn));
1925
1926 /* Return the user pointer associated with the error functions */
1927 extern PNG_EXPORT(png_voidp,png_get_error_ptr) PNGARG((png_structp png_ptr));
1928
1929 /* Replace the default data output functions with a user supplied one(s).
1930 * If buffered output is not used, then output_flush_fn can be set to NULL.
1931 * If PNG_WRITE_FLUSH_SUPPORTED is not defined at libpng compile time
1932 * output_flush_fn will be ignored (and thus can be NULL).
1933 */
1934 extern PNG_EXPORT(void,png_set_write_fn) PNGARG((png_structp png_ptr,
1935 png_voidp io_ptr, png_rw_ptr write_data_fn, png_flush_ptr output_flush_fn));
1936
1937 /* Replace the default data input function with a user supplied one. */
1938 extern PNG_EXPORT(void,png_set_read_fn) PNGARG((png_structp png_ptr,
1939 png_voidp io_ptr, png_rw_ptr read_data_fn));
1940
1941 /* Return the user pointer associated with the I/O functions */
1942 extern PNG_EXPORT(png_voidp,png_get_io_ptr) PNGARG((png_structp png_ptr));
1943
1944 extern PNG_EXPORT(void,png_set_read_status_fn) PNGARG((png_structp png_ptr,
1945 png_read_status_ptr read_row_fn));
1946
1947 extern PNG_EXPORT(void,png_set_write_status_fn) PNGARG((png_structp png_ptr,
1948 png_write_status_ptr write_row_fn));
1949
1950 #ifdef PNG_USER_MEM_SUPPORTED
1951 /* Replace the default memory allocation functions with user supplied one(s). */
1952 extern PNG_EXPORT(void,png_set_mem_fn) PNGARG((png_structp png_ptr,
1953 png_voidp mem_ptr, png_malloc_ptr malloc_fn, png_free_ptr free_fn));
1954 /* Return the user pointer associated with the memory functions */
1955 extern PNG_EXPORT(png_voidp,png_get_mem_ptr) PNGARG((png_structp png_ptr));
1956 #endif
1957
1958 #if defined(PNG_READ_USER_TRANSFORM_SUPPORTED) || \
1959 defined(PNG_LEGACY_SUPPORTED)
1960 extern PNG_EXPORT(void,png_set_read_user_transform_fn) PNGARG((png_structp
1961 png_ptr, png_user_transform_ptr read_user_transform_fn));
1962 #endif
1963
1964 #if defined(PNG_WRITE_USER_TRANSFORM_SUPPORTED) || \
1965 defined(PNG_LEGACY_SUPPORTED)
1966 extern PNG_EXPORT(void,png_set_write_user_transform_fn) PNGARG((png_structp
1967 png_ptr, png_user_transform_ptr write_user_transform_fn));
1968 #endif
1969
1970 #if defined(PNG_READ_USER_TRANSFORM_SUPPORTED) || \
1971 defined(PNG_WRITE_USER_TRANSFORM_SUPPORTED) || \
1972 defined(PNG_LEGACY_SUPPORTED)
1973 extern PNG_EXPORT(void,png_set_user_transform_info) PNGARG((png_structp
1974 png_ptr, png_voidp user_transform_ptr, int user_transform_depth,
1975 int user_transform_channels));
1976 /* Return the user pointer associated with the user transform functions */
1977 extern PNG_EXPORT(png_voidp,png_get_user_transform_ptr)
1978 PNGARG((png_structp png_ptr));
1979 #endif
1980
1981 #ifdef PNG_USER_CHUNKS_SUPPORTED
1982 extern PNG_EXPORT(void,png_set_read_user_chunk_fn) PNGARG((png_structp png_ptr,
1983 png_voidp user_chunk_ptr, png_user_chunk_ptr read_user_chunk_fn));
1984 extern PNG_EXPORT(png_voidp,png_get_user_chunk_ptr) PNGARG((png_structp
1985 png_ptr));
1986 #endif
1987
1988 #ifdef PNG_PROGRESSIVE_READ_SUPPORTED
1989 /* Sets the function callbacks for the push reader, and a pointer to a
1990 * user-defined structure available to the callback functions.
1991 */
1992 extern PNG_EXPORT(void,png_set_progressive_read_fn) PNGARG((png_structp png_ptr,
1993 png_voidp progressive_ptr,
1994 png_progressive_info_ptr info_fn, png_progressive_row_ptr row_fn,
1995 png_progressive_end_ptr end_fn));
1996
1997 /* returns the user pointer associated with the push read functions */
1998 extern PNG_EXPORT(png_voidp,png_get_progressive_ptr)
1999 PNGARG((png_structp png_ptr));
2000
2001 /* function to be called when data becomes available */
2002 extern PNG_EXPORT(void,png_process_data) PNGARG((png_structp png_ptr,
2003 png_infop info_ptr, png_bytep buffer, png_size_t buffer_size));
2004
2005 /* function that combines rows. Not very much different than the
2006 * png_combine_row() call. Is this even used?????
2007 */
2008 extern PNG_EXPORT(void,png_progressive_combine_row) PNGARG((png_structp png_ptr,
2009 png_bytep old_row, png_bytep new_row));
2010 #endif /* PNG_PROGRESSIVE_READ_SUPPORTED */
2011
2012 extern PNG_EXPORT(png_voidp,png_malloc) PNGARG((png_structp png_ptr,
2013 png_uint_32 size));
2014
2015 #if defined(PNG_1_0_X)
2016 # define png_malloc_warn png_malloc
2017 #else
2018 /* Added at libpng version 1.2.4 */
2019 extern PNG_EXPORT(png_voidp,png_malloc_warn) PNGARG((png_structp png_ptr,
2020 png_uint_32 size));
2021 #endif
2022
2023 /* frees a pointer allocated by png_malloc() */
2024 extern PNG_EXPORT(void,png_free) PNGARG((png_structp png_ptr, png_voidp ptr));
2025
2026 #if defined(PNG_1_0_X)
2027 /* Function to allocate memory for zlib. */
2028 extern PNG_EXPORT(voidpf,png_zalloc) PNGARG((voidpf png_ptr, uInt items,
2029 uInt size));
2030
2031 /* Function to free memory for zlib */
2032 extern PNG_EXPORT(void,png_zfree) PNGARG((voidpf png_ptr, voidpf ptr));
2033 #endif
2034
2035 /* Free data that was allocated internally */
2036 extern PNG_EXPORT(void,png_free_data) PNGARG((png_structp png_ptr,
2037 png_infop info_ptr, png_uint_32 free_me, int num));
2038 #ifdef PNG_FREE_ME_SUPPORTED
2039 /* Reassign responsibility for freeing existing data, whether allocated
2040 * by libpng or by the application */
2041 extern PNG_EXPORT(void,png_data_freer) PNGARG((png_structp png_ptr,
2042 png_infop info_ptr, int freer, png_uint_32 mask));
2043 #endif
2044 /* assignments for png_data_freer */
2045 #define PNG_DESTROY_WILL_FREE_DATA 1
2046 #define PNG_SET_WILL_FREE_DATA 1
2047 #define PNG_USER_WILL_FREE_DATA 2
2048 /* Flags for png_ptr->free_me and info_ptr->free_me */
2049 #define PNG_FREE_HIST 0x0008
2050 #define PNG_FREE_ICCP 0x0010
2051 #define PNG_FREE_SPLT 0x0020
2052 #define PNG_FREE_ROWS 0x0040
2053 #define PNG_FREE_PCAL 0x0080
2054 #define PNG_FREE_SCAL 0x0100
2055 #define PNG_FREE_UNKN 0x0200
2056 #define PNG_FREE_LIST 0x0400
2057 #define PNG_FREE_PLTE 0x1000
2058 #define PNG_FREE_TRNS 0x2000
2059 #define PNG_FREE_TEXT 0x4000
2060 #define PNG_FREE_ALL 0x7fff
2061 #define PNG_FREE_MUL 0x4220 /* PNG_FREE_SPLT|PNG_FREE_TEXT|PNG_FREE_UNKN */
2062
2063 #ifdef PNG_USER_MEM_SUPPORTED
2064 extern PNG_EXPORT(png_voidp,png_malloc_default) PNGARG((png_structp png_ptr,
2065 png_uint_32 size));
2066 extern PNG_EXPORT(void,png_free_default) PNGARG((png_structp png_ptr,
2067 png_voidp ptr));
2068 #endif
2069
2070 extern PNG_EXPORT(png_voidp,png_memcpy_check) PNGARG((png_structp png_ptr,
2071 png_voidp s1, png_voidp s2, png_uint_32 size));
2072
2073 extern PNG_EXPORT(png_voidp,png_memset_check) PNGARG((png_structp png_ptr,
2074 png_voidp s1, int value, png_uint_32 size));
2075
2076 #if defined(USE_FAR_KEYWORD) /* memory model conversion function */
2077 extern void *png_far_to_near PNGARG((png_structp png_ptr,png_voidp ptr,
2078 int check));
2079 #endif /* USE_FAR_KEYWORD */
2080
2081 #ifndef PNG_NO_ERROR_TEXT
2082 /* Fatal error in PNG image of libpng - can't continue */
2083 extern PNG_EXPORT(void,png_error) PNGARG((png_structp png_ptr,
2084 png_const_charp error_message));
2085
2086 /* The same, but the chunk name is prepended to the error string. */
2087 extern PNG_EXPORT(void,png_chunk_error) PNGARG((png_structp png_ptr,
2088 png_const_charp error_message));
2089 #else
2090 /* Fatal error in PNG image of libpng - can't continue */
2091 extern PNG_EXPORT(void,png_err) PNGARG((png_structp png_ptr));
2092 #endif
2093
2094 #ifndef PNG_NO_WARNINGS
2095 /* Non-fatal error in libpng. Can continue, but may have a problem. */
2096 extern PNG_EXPORT(void,png_warning) PNGARG((png_structp png_ptr,
2097 png_const_charp warning_message));
2098
2099 #ifdef PNG_READ_SUPPORTED
2100 /* Non-fatal error in libpng, chunk name is prepended to message. */
2101 extern PNG_EXPORT(void,png_chunk_warning) PNGARG((png_structp png_ptr,
2102 png_const_charp warning_message));
2103 #endif /* PNG_READ_SUPPORTED */
2104 #endif /* PNG_NO_WARNINGS */
2105
2106 /* The png_set_<chunk> functions are for storing values in the png_info_struct.
2107 * Similarly, the png_get_<chunk> calls are used to read values from the
2108 * png_info_struct, either storing the parameters in the passed variables, or
2109 * setting pointers into the png_info_struct where the data is stored. The
2110 * png_get_<chunk> functions return a non-zero value if the data was available
2111 * in info_ptr, or return zero and do not change any of the parameters if the
2112 * data was not available.
2113 *
2114 * These functions should be used instead of directly accessing png_info
2115 * to avoid problems with future changes in the size and internal layout of
2116 * png_info_struct.
2117 */
2118 /* Returns "flag" if chunk data is valid in info_ptr. */
2119 extern PNG_EXPORT(png_uint_32,png_get_valid) PNGARG((png_structp png_ptr,
2120 png_infop info_ptr, png_uint_32 flag));
2121
2122 /* Returns number of bytes needed to hold a transformed row. */
2123 extern PNG_EXPORT(png_uint_32,png_get_rowbytes) PNGARG((png_structp png_ptr,
2124 png_infop info_ptr));
2125
2126 #if defined(PNG_INFO_IMAGE_SUPPORTED)
2127 /* Returns row_pointers, which is an array of pointers to scanlines that was
2128 returned from png_read_png(). */
2129 extern PNG_EXPORT(png_bytepp,png_get_rows) PNGARG((png_structp png_ptr,
2130 png_infop info_ptr));
2131 /* Set row_pointers, which is an array of pointers to scanlines for use
2132 by png_write_png(). */
2133 extern PNG_EXPORT(void,png_set_rows) PNGARG((png_structp png_ptr,
2134 png_infop info_ptr, png_bytepp row_pointers));
2135 #endif
2136
2137 /* Returns number of color channels in image. */
2138 extern PNG_EXPORT(png_byte,png_get_channels) PNGARG((png_structp png_ptr,
2139 png_infop info_ptr));
2140
2141 #ifdef PNG_EASY_ACCESS_SUPPORTED
2142 /* Returns image width in pixels. */
2143 extern PNG_EXPORT(png_uint_32, png_get_image_width) PNGARG((png_structp
2144 png_ptr, png_infop info_ptr));
2145
2146 /* Returns image height in pixels. */
2147 extern PNG_EXPORT(png_uint_32, png_get_image_height) PNGARG((png_structp
2148 png_ptr, png_infop info_ptr));
2149
2150 /* Returns image bit_depth. */
2151 extern PNG_EXPORT(png_byte, png_get_bit_depth) PNGARG((png_structp
2152 png_ptr, png_infop info_ptr));
2153
2154 /* Returns image color_type. */
2155 extern PNG_EXPORT(png_byte, png_get_color_type) PNGARG((png_structp
2156 png_ptr, png_infop info_ptr));
2157
2158 /* Returns image filter_type. */
2159 extern PNG_EXPORT(png_byte, png_get_filter_type) PNGARG((png_structp
2160 png_ptr, png_infop info_ptr));
2161
2162 /* Returns image interlace_type. */
2163 extern PNG_EXPORT(png_byte, png_get_interlace_type) PNGARG((png_structp
2164 png_ptr, png_infop info_ptr));
2165
2166 /* Returns image compression_type. */
2167 extern PNG_EXPORT(png_byte, png_get_compression_type) PNGARG((png_structp
2168 png_ptr, png_infop info_ptr));
2169
2170 /* Returns image resolution in pixels per meter, from pHYs chunk data. */
2171 extern PNG_EXPORT(png_uint_32, png_get_pixels_per_meter) PNGARG((png_structp
2172 png_ptr, png_infop info_ptr));
2173 extern PNG_EXPORT(png_uint_32, png_get_x_pixels_per_meter) PNGARG((png_structp
2174 png_ptr, png_infop info_ptr));
2175 extern PNG_EXPORT(png_uint_32, png_get_y_pixels_per_meter) PNGARG((png_structp
2176 png_ptr, png_infop info_ptr));
2177
2178 /* Returns pixel aspect ratio, computed from pHYs chunk data. */
2179 #ifdef PNG_FLOATING_POINT_SUPPORTED
2180 extern PNG_EXPORT(float, png_get_pixel_aspect_ratio) PNGARG((png_structp
2181 png_ptr, png_infop info_ptr));
2182 #endif
2183
2184 /* Returns image x, y offset in pixels or microns, from oFFs chunk data. */
2185 extern PNG_EXPORT(png_int_32, png_get_x_offset_pixels) PNGARG((png_structp
2186 png_ptr, png_infop info_ptr));
2187 extern PNG_EXPORT(png_int_32, png_get_y_offset_pixels) PNGARG((png_structp
2188 png_ptr, png_infop info_ptr));
2189 extern PNG_EXPORT(png_int_32, png_get_x_offset_microns) PNGARG((png_structp
2190 png_ptr, png_infop info_ptr));
2191 extern PNG_EXPORT(png_int_32, png_get_y_offset_microns) PNGARG((png_structp
2192 png_ptr, png_infop info_ptr));
2193
2194 #endif /* PNG_EASY_ACCESS_SUPPORTED */
2195
2196 /* Returns pointer to signature string read from PNG header */
2197 extern PNG_EXPORT(png_bytep,png_get_signature) PNGARG((png_structp png_ptr,
2198 png_infop info_ptr));
2199
2200 #if defined(PNG_bKGD_SUPPORTED)
2201 extern PNG_EXPORT(png_uint_32,png_get_bKGD) PNGARG((png_structp png_ptr,
2202 png_infop info_ptr, png_color_16p *background));
2203 #endif
2204
2205 #if defined(PNG_bKGD_SUPPORTED)
2206 extern PNG_EXPORT(void,png_set_bKGD) PNGARG((png_structp png_ptr,
2207 png_infop info_ptr, png_color_16p background));
2208 #endif
2209
2210 #if defined(PNG_cHRM_SUPPORTED)
2211 #ifdef PNG_FLOATING_POINT_SUPPORTED
2212 extern PNG_EXPORT(png_uint_32,png_get_cHRM) PNGARG((png_structp png_ptr,
2213 png_infop info_ptr, double *white_x, double *white_y, double *red_x,
2214 double *red_y, double *green_x, double *green_y, double *blue_x,
2215 double *blue_y));
2216 #endif
2217 #ifdef PNG_FIXED_POINT_SUPPORTED
2218 extern PNG_EXPORT(png_uint_32,png_get_cHRM_fixed) PNGARG((png_structp png_ptr,
2219 png_infop info_ptr, png_fixed_point *int_white_x, png_fixed_point
2220 *int_white_y, png_fixed_point *int_red_x, png_fixed_point *int_red_y,
2221 png_fixed_point *int_green_x, png_fixed_point *int_green_y, png_fixed_point
2222 *int_blue_x, png_fixed_point *int_blue_y));
2223 #endif
2224 #endif
2225
2226 #if defined(PNG_cHRM_SUPPORTED)
2227 #ifdef PNG_FLOATING_POINT_SUPPORTED
2228 extern PNG_EXPORT(void,png_set_cHRM) PNGARG((png_structp png_ptr,
2229 png_infop info_ptr, double white_x, double white_y, double red_x,
2230 double red_y, double green_x, double green_y, double blue_x, double blue_y));
2231 #endif
2232 #ifdef PNG_FIXED_POINT_SUPPORTED
2233 extern PNG_EXPORT(void,png_set_cHRM_fixed) PNGARG((png_structp png_ptr,
2234 png_infop info_ptr, png_fixed_point int_white_x, png_fixed_point int_white_y,
2235 png_fixed_point int_red_x, png_fixed_point int_red_y, png_fixed_point
2236 int_green_x, png_fixed_point int_green_y, png_fixed_point int_blue_x,
2237 png_fixed_point int_blue_y));
2238 #endif
2239 #endif
2240
2241 #if defined(PNG_gAMA_SUPPORTED)
2242 #ifdef PNG_FLOATING_POINT_SUPPORTED
2243 extern PNG_EXPORT(png_uint_32,png_get_gAMA) PNGARG((png_structp png_ptr,
2244 png_infop info_ptr, double *file_gamma));
2245 #endif
2246 extern PNG_EXPORT(png_uint_32,png_get_gAMA_fixed) PNGARG((png_structp png_ptr,
2247 png_infop info_ptr, png_fixed_point *int_file_gamma));
2248 #endif
2249
2250 #if defined(PNG_gAMA_SUPPORTED)
2251 #ifdef PNG_FLOATING_POINT_SUPPORTED
2252 extern PNG_EXPORT(void,png_set_gAMA) PNGARG((png_structp png_ptr,
2253 png_infop info_ptr, double file_gamma));
2254 #endif
2255 extern PNG_EXPORT(void,png_set_gAMA_fixed) PNGARG((png_structp png_ptr,
2256 png_infop info_ptr, png_fixed_point int_file_gamma));
2257 #endif
2258
2259 #if defined(PNG_hIST_SUPPORTED)
2260 extern PNG_EXPORT(png_uint_32,png_get_hIST) PNGARG((png_structp png_ptr,
2261 png_infop info_ptr, png_uint_16p *hist));
2262 #endif
2263
2264 #if defined(PNG_hIST_SUPPORTED)
2265 extern PNG_EXPORT(void,png_set_hIST) PNGARG((png_structp png_ptr,
2266 png_infop info_ptr, png_uint_16p hist));
2267 #endif
2268
2269 extern PNG_EXPORT(png_uint_32,png_get_IHDR) PNGARG((png_structp png_ptr,
2270 png_infop info_ptr, png_uint_32 *width, png_uint_32 *height,
2271 int *bit_depth, int *color_type, int *interlace_method,
2272 int *compression_method, int *filter_method));
2273
2274 extern PNG_EXPORT(void,png_set_IHDR) PNGARG((png_structp png_ptr,
2275 png_infop info_ptr, png_uint_32 width, png_uint_32 height, int bit_depth,
2276 int color_type, int interlace_method, int compression_method,
2277 int filter_method));
2278
2279 #if defined(PNG_oFFs_SUPPORTED)
2280 extern PNG_EXPORT(png_uint_32,png_get_oFFs) PNGARG((png_structp png_ptr,
2281 png_infop info_ptr, png_int_32 *offset_x, png_int_32 *offset_y,
2282 int *unit_type));
2283 #endif
2284
2285 #if defined(PNG_oFFs_SUPPORTED)
2286 extern PNG_EXPORT(void,png_set_oFFs) PNGARG((png_structp png_ptr,
2287 png_infop info_ptr, png_int_32 offset_x, png_int_32 offset_y,
2288 int unit_type));
2289 #endif
2290
2291 #if defined(PNG_pCAL_SUPPORTED)
2292 extern PNG_EXPORT(png_uint_32,png_get_pCAL) PNGARG((png_structp png_ptr,
2293 png_infop info_ptr, png_charp *purpose, png_int_32 *X0, png_int_32 *X1,
2294 int *type, int *nparams, png_charp *units, png_charpp *params));
2295 #endif
2296
2297 #if defined(PNG_pCAL_SUPPORTED)
2298 extern PNG_EXPORT(void,png_set_pCAL) PNGARG((png_structp png_ptr,
2299 png_infop info_ptr, png_charp purpose, png_int_32 X0, png_int_32 X1,
2300 int type, int nparams, png_charp units, png_charpp params));
2301 #endif
2302
2303 #if defined(PNG_pHYs_SUPPORTED)
2304 extern PNG_EXPORT(png_uint_32,png_get_pHYs) PNGARG((png_structp png_ptr,
2305 png_infop info_ptr, png_uint_32 *res_x, png_uint_32 *res_y, int *unit_type));
2306 #endif
2307
2308 #if defined(PNG_pHYs_SUPPORTED)
2309 extern PNG_EXPORT(void,png_set_pHYs) PNGARG((png_structp png_ptr,
2310 png_infop info_ptr, png_uint_32 res_x, png_uint_32 res_y, int unit_type));
2311 #endif
2312
2313 extern PNG_EXPORT(png_uint_32,png_get_PLTE) PNGARG((png_structp png_ptr,
2314 png_infop info_ptr, png_colorp *palette, int *num_palette));
2315
2316 extern PNG_EXPORT(void,png_set_PLTE) PNGARG((png_structp png_ptr,
2317 png_infop info_ptr, png_colorp palette, int num_palette));
2318
2319 #if defined(PNG_sBIT_SUPPORTED)
2320 extern PNG_EXPORT(png_uint_32,png_get_sBIT) PNGARG((png_structp png_ptr,
2321 png_infop info_ptr, png_color_8p *sig_bit));
2322 #endif
2323
2324 #if defined(PNG_sBIT_SUPPORTED)
2325 extern PNG_EXPORT(void,png_set_sBIT) PNGARG((png_structp png_ptr,
2326 png_infop info_ptr, png_color_8p sig_bit));
2327 #endif
2328
2329 #if defined(PNG_sRGB_SUPPORTED)
2330 extern PNG_EXPORT(png_uint_32,png_get_sRGB) PNGARG((png_structp png_ptr,
2331 png_infop info_ptr, int *intent));
2332 #endif
2333
2334 #if defined(PNG_sRGB_SUPPORTED)
2335 extern PNG_EXPORT(void,png_set_sRGB) PNGARG((png_structp png_ptr,
2336 png_infop info_ptr, int intent));
2337 extern PNG_EXPORT(void,png_set_sRGB_gAMA_and_cHRM) PNGARG((png_structp png_ptr,
2338 png_infop info_ptr, int intent));
2339 #endif
2340
2341 #if defined(PNG_iCCP_SUPPORTED)
2342 extern PNG_EXPORT(png_uint_32,png_get_iCCP) PNGARG((png_structp png_ptr,
2343 png_infop info_ptr, png_charpp name, int *compression_type,
2344 png_charpp profile, png_uint_32 *proflen));
2345 /* Note to maintainer: profile should be png_bytepp */
2346 #endif
2347
2348 #if defined(PNG_iCCP_SUPPORTED)
2349 extern PNG_EXPORT(void,png_set_iCCP) PNGARG((png_structp png_ptr,
2350 png_infop info_ptr, png_charp name, int compression_type,
2351 png_charp profile, png_uint_32 proflen));
2352 /* Note to maintainer: profile should be png_bytep */
2353 #endif
2354
2355 #if defined(PNG_sPLT_SUPPORTED)
2356 extern PNG_EXPORT(png_uint_32,png_get_sPLT) PNGARG((png_structp png_ptr,
2357 png_infop info_ptr, png_sPLT_tpp entries));
2358 #endif
2359
2360 #if defined(PNG_sPLT_SUPPORTED)
2361 extern PNG_EXPORT(void,png_set_sPLT) PNGARG((png_structp png_ptr,
2362 png_infop info_ptr, png_sPLT_tp entries, int nentries));
2363 #endif
2364
2365 #if defined(PNG_TEXT_SUPPORTED)
2366 /* png_get_text also returns the number of text chunks in *num_text */
2367 extern PNG_EXPORT(png_uint_32,png_get_text) PNGARG((png_structp png_ptr,
2368 png_infop info_ptr, png_textp *text_ptr, int *num_text));
2369 #endif
2370
2371 /*
2372 * Note while png_set_text() will accept a structure whose text,
2373 * language, and translated keywords are NULL pointers, the structure
2374 * returned by png_get_text will always contain regular
2375 * zero-terminated C strings. They might be empty strings but
2376 * they will never be NULL pointers.
2377 */
2378
2379 #if defined(PNG_TEXT_SUPPORTED)
2380 extern PNG_EXPORT(void,png_set_text) PNGARG((png_structp png_ptr,
2381 png_infop info_ptr, png_textp text_ptr, int num_text));
2382 #endif
2383
2384 #if defined(PNG_tIME_SUPPORTED)
2385 extern PNG_EXPORT(png_uint_32,png_get_tIME) PNGARG((png_structp png_ptr,
2386 png_infop info_ptr, png_timep *mod_time));
2387 #endif
2388
2389 #if defined(PNG_tIME_SUPPORTED)
2390 extern PNG_EXPORT(void,png_set_tIME) PNGARG((png_structp png_ptr,
2391 png_infop info_ptr, png_timep mod_time));
2392 #endif
2393
2394 #if defined(PNG_tRNS_SUPPORTED)
2395 extern PNG_EXPORT(png_uint_32,png_get_tRNS) PNGARG((png_structp png_ptr,
2396 png_infop info_ptr, png_bytep *trans, int *num_trans,
2397 png_color_16p *trans_values));
2398 #endif
2399
2400 #if defined(PNG_tRNS_SUPPORTED)
2401 extern PNG_EXPORT(void,png_set_tRNS) PNGARG((png_structp png_ptr,
2402 png_infop info_ptr, png_bytep trans, int num_trans,
2403 png_color_16p trans_values));
2404 #endif
2405
2406 #if defined(PNG_tRNS_SUPPORTED)
2407 #endif
2408
2409 #if defined(PNG_sCAL_SUPPORTED)
2410 #ifdef PNG_FLOATING_POINT_SUPPORTED
2411 extern PNG_EXPORT(png_uint_32,png_get_sCAL) PNGARG((png_structp png_ptr,
2412 png_infop info_ptr, int *unit, double *width, double *height));
2413 #else
2414 #ifdef PNG_FIXED_POINT_SUPPORTED
2415 extern PNG_EXPORT(png_uint_32,png_get_sCAL_s) PNGARG((png_structp png_ptr,
2416 png_infop info_ptr, int *unit, png_charpp swidth, png_charpp sheight));
2417 #endif
2418 #endif
2419 #endif /* PNG_sCAL_SUPPORTED */
2420
2421 #if defined(PNG_sCAL_SUPPORTED)
2422 #ifdef PNG_FLOATING_POINT_SUPPORTED
2423 extern PNG_EXPORT(void,png_set_sCAL) PNGARG((png_structp png_ptr,
2424 png_infop info_ptr, int unit, double width, double height));
2425 #else
2426 #ifdef PNG_FIXED_POINT_SUPPORTED
2427 extern PNG_EXPORT(void,png_set_sCAL_s) PNGARG((png_structp png_ptr,
2428 png_infop info_ptr, int unit, png_charp swidth, png_charp sheight));
2429 #endif
2430 #endif
2431 #endif /* PNG_sCAL_SUPPORTED || PNG_WRITE_sCAL_SUPPORTED */
2432
2433 #if defined(PNG_UNKNOWN_CHUNKS_SUPPORTED)
2434 /* provide a list of chunks and how they are to be handled, if the built-in
2435 handling or default unknown chunk handling is not desired. Any chunks not
2436 listed will be handled in the default manner. The IHDR and IEND chunks
2437 must not be listed.
2438 keep = 0: follow default behaviour
2439 = 1: do not keep
2440 = 2: keep only if safe-to-copy
2441 = 3: keep even if unsafe-to-copy
2442 */
2443 extern PNG_EXPORT(void, png_set_keep_unknown_chunks) PNGARG((png_structp
2444 png_ptr, int keep, png_bytep chunk_list, int num_chunks));
2445 extern PNG_EXPORT(void, png_set_unknown_chunks) PNGARG((png_structp png_ptr,
2446 png_infop info_ptr, png_unknown_chunkp unknowns, int num_unknowns));
2447 extern PNG_EXPORT(void, png_set_unknown_chunk_location)
2448 PNGARG((png_structp png_ptr, png_infop info_ptr, int chunk, int location));
2449 extern PNG_EXPORT(png_uint_32,png_get_unknown_chunks) PNGARG((png_structp
2450 png_ptr, png_infop info_ptr, png_unknown_chunkpp entries));
2451 #endif
2452 #ifdef PNG_HANDLE_AS_UNKNOWN_SUPPORTED
2453 PNG_EXPORT(int,png_handle_as_unknown) PNGARG((png_structp png_ptr, png_bytep
2454 chunk_name));
2455 #endif
2456
2457 /* Png_free_data() will turn off the "valid" flag for anything it frees.
2458 If you need to turn it off for a chunk that your application has freed,
2459 you can use png_set_invalid(png_ptr, info_ptr, PNG_INFO_CHNK); */
2460 extern PNG_EXPORT(void, png_set_invalid) PNGARG((png_structp png_ptr,
2461 png_infop info_ptr, int mask));
2462
2463 #if defined(PNG_INFO_IMAGE_SUPPORTED)
2464 /* The "params" pointer is currently not used and is for future expansion. */
2465 extern PNG_EXPORT(void, png_read_png) PNGARG((png_structp png_ptr,
2466 png_infop info_ptr,
2467 int transforms,
2468 png_voidp params));
2469 extern PNG_EXPORT(void, png_write_png) PNGARG((png_structp png_ptr,
2470 png_infop info_ptr,
2471 int transforms,
2472 png_voidp params));
2473 #endif
2474
2475 /* Define PNG_DEBUG at compile time for debugging information. Higher
2476 * numbers for PNG_DEBUG mean more debugging information. This has
2477 * only been added since version 0.95 so it is not implemented throughout
2478 * libpng yet, but more support will be added as needed.
2479 */
2480 #ifdef PNG_DEBUG
2481 #if (PNG_DEBUG > 0)
2482 #if !defined(PNG_DEBUG_FILE) && defined(_MSC_VER)
2483 #include <crtdbg.h>
2484 #if (PNG_DEBUG > 1)
2485 #define png_debug(l,m) _RPT0(_CRT_WARN,m)
2486 #define png_debug1(l,m,p1) _RPT1(_CRT_WARN,m,p1)
2487 #define png_debug2(l,m,p1,p2) _RPT2(_CRT_WARN,m,p1,p2)
2488 #endif
2489 #else /* PNG_DEBUG_FILE || !_MSC_VER */
2490 #ifndef PNG_DEBUG_FILE
2491 #define PNG_DEBUG_FILE stderr
2492 #endif /* PNG_DEBUG_FILE */
2493 #if (PNG_DEBUG > 1)
2494 #define png_debug(l,m) \
2495 { \
2496 int num_tabs=l; \
2497 fprintf(PNG_DEBUG_FILE,"%s"m,(num_tabs==1 ? "\t" : \
2498 (num_tabs==2 ? "\t\t":(num_tabs>2 ? "\t\t\t":"")))); \
2499 }
2500 #define png_debug1(l,m,p1) \
2501 { \
2502 int num_tabs=l; \
2503 fprintf(PNG_DEBUG_FILE,"%s"m,(num_tabs==1 ? "\t" : \
2504 (num_tabs==2 ? "\t\t":(num_tabs>2 ? "\t\t\t":""))),p1); \
2505 }
2506 #define png_debug2(l,m,p1,p2) \
2507 { \
2508 int num_tabs=l; \
2509 fprintf(PNG_DEBUG_FILE,"%s"m,(num_tabs==1 ? "\t" : \
2510 (num_tabs==2 ? "\t\t":(num_tabs>2 ? "\t\t\t":""))),p1,p2); \
2511 }
2512 #endif /* (PNG_DEBUG > 1) */
2513 #endif /* _MSC_VER */
2514 #endif /* (PNG_DEBUG > 0) */
2515 #endif /* PNG_DEBUG */
2516 #ifndef png_debug
2517 #define png_debug(l, m)
2518 #endif
2519 #ifndef png_debug1
2520 #define png_debug1(l, m, p1)
2521 #endif
2522 #ifndef png_debug2
2523 #define png_debug2(l, m, p1, p2)
2524 #endif
2525
2526 extern PNG_EXPORT(png_charp,png_get_copyright) PNGARG((png_structp png_ptr));
2527 extern PNG_EXPORT(png_charp,png_get_header_ver) PNGARG((png_structp png_ptr));
2528 extern PNG_EXPORT(png_charp,png_get_header_version) PNGARG((png_structp png_ptr));
2529 extern PNG_EXPORT(png_charp,png_get_libpng_ver) PNGARG((png_structp png_ptr));
2530
2531 #ifdef PNG_MNG_FEATURES_SUPPORTED
2532 extern PNG_EXPORT(png_uint_32,png_permit_mng_features) PNGARG((png_structp
2533 png_ptr, png_uint_32 mng_features_permitted));
2534 #endif
2535
2536 /* For use in png_set_keep_unknown, added to version 1.2.6 */
2537 #define PNG_HANDLE_CHUNK_AS_DEFAULT 0
2538 #define PNG_HANDLE_CHUNK_NEVER 1
2539 #define PNG_HANDLE_CHUNK_IF_SAFE 2
2540 #define PNG_HANDLE_CHUNK_ALWAYS 3
2541
2542 /* Added to version 1.2.0 */
2543 #if defined(PNG_ASSEMBLER_CODE_SUPPORTED)
2544 #if defined(PNG_MMX_CODE_SUPPORTED)
2545 #define PNG_ASM_FLAG_MMX_SUPPORT_COMPILED 0x01 /* not user-settable */
2546 #define PNG_ASM_FLAG_MMX_SUPPORT_IN_CPU 0x02 /* not user-settable */
2547 #define PNG_ASM_FLAG_MMX_READ_COMBINE_ROW 0x04
2548 #define PNG_ASM_FLAG_MMX_READ_INTERLACE 0x08
2549 #define PNG_ASM_FLAG_MMX_READ_FILTER_SUB 0x10
2550 #define PNG_ASM_FLAG_MMX_READ_FILTER_UP 0x20
2551 #define PNG_ASM_FLAG_MMX_READ_FILTER_AVG 0x40
2552 #define PNG_ASM_FLAG_MMX_READ_FILTER_PAETH 0x80
2553 #define PNG_ASM_FLAGS_INITIALIZED 0x80000000 /* not user-settable */
2554
2555 #define PNG_MMX_READ_FLAGS ( PNG_ASM_FLAG_MMX_READ_COMBINE_ROW \
2556 | PNG_ASM_FLAG_MMX_READ_INTERLACE \
2557 | PNG_ASM_FLAG_MMX_READ_FILTER_SUB \
2558 | PNG_ASM_FLAG_MMX_READ_FILTER_UP \
2559 | PNG_ASM_FLAG_MMX_READ_FILTER_AVG \
2560 | PNG_ASM_FLAG_MMX_READ_FILTER_PAETH )
2561 #define PNG_MMX_WRITE_FLAGS ( 0 )
2562
2563 #define PNG_MMX_FLAGS ( PNG_ASM_FLAG_MMX_SUPPORT_COMPILED \
2564 | PNG_ASM_FLAG_MMX_SUPPORT_IN_CPU \
2565 | PNG_MMX_READ_FLAGS \
2566 | PNG_MMX_WRITE_FLAGS )
2567
2568 #define PNG_SELECT_READ 1
2569 #define PNG_SELECT_WRITE 2
2570 #endif /* PNG_MMX_CODE_SUPPORTED */
2571
2572 #if !defined(PNG_1_0_X)
2573 /* pngget.c */
2574 extern PNG_EXPORT(png_uint_32,png_get_mmx_flagmask)
2575 PNGARG((int flag_select, int *compilerID));
2576
2577 /* pngget.c */
2578 extern PNG_EXPORT(png_uint_32,png_get_asm_flagmask)
2579 PNGARG((int flag_select));
2580
2581 /* pngget.c */
2582 extern PNG_EXPORT(png_uint_32,png_get_asm_flags)
2583 PNGARG((png_structp png_ptr));
2584
2585 /* pngget.c */
2586 extern PNG_EXPORT(png_byte,png_get_mmx_bitdepth_threshold)
2587 PNGARG((png_structp png_ptr));
2588
2589 /* pngget.c */
2590 extern PNG_EXPORT(png_uint_32,png_get_mmx_rowbytes_threshold)
2591 PNGARG((png_structp png_ptr));
2592
2593 /* pngset.c */
2594 extern PNG_EXPORT(void,png_set_asm_flags)
2595 PNGARG((png_structp png_ptr, png_uint_32 asm_flags));
2596
2597 /* pngset.c */
2598 extern PNG_EXPORT(void,png_set_mmx_thresholds)
2599 PNGARG((png_structp png_ptr, png_byte mmx_bitdepth_threshold,
2600 png_uint_32 mmx_rowbytes_threshold));
2601
2602 #endif /* PNG_1_0_X */
2603
2604 #if !defined(PNG_1_0_X)
2605 /* png.c, pnggccrd.c, or pngvcrd.c */
2606 extern PNG_EXPORT(int,png_mmx_support) PNGARG((void));
2607 #endif /* PNG_ASSEMBLER_CODE_SUPPORTED */
2608
2609 /* Strip the prepended error numbers ("#nnn ") from error and warning
2610 * messages before passing them to the error or warning handler. */
2611 #ifdef PNG_ERROR_NUMBERS_SUPPORTED
2612 extern PNG_EXPORT(void,png_set_strip_error_numbers) PNGARG((png_structp
2613 png_ptr, png_uint_32 strip_mode));
2614 #endif
2615
2616 #endif /* PNG_1_0_X */
2617
2618 /* Added at libpng-1.2.6 */
2619 #ifdef PNG_SET_USER_LIMITS_SUPPORTED
2620 extern PNG_EXPORT(void,png_set_user_limits) PNGARG((png_structp
2621 png_ptr, png_uint_32 user_width_max, png_uint_32 user_height_max));
2622 extern PNG_EXPORT(png_uint_32,png_get_user_width_max) PNGARG((png_structp
2623 png_ptr));
2624 extern PNG_EXPORT(png_uint_32,png_get_user_height_max) PNGARG((png_structp
2625 png_ptr));
2626 #endif
2627
2628 /* Maintainer: Put new public prototypes here ^, in libpng.3, and project defs */
2629
2630 #ifdef PNG_READ_COMPOSITE_NODIV_SUPPORTED
2631 /* With these routines we avoid an integer divide, which will be slower on
2632 * most machines. However, it does take more operations than the corresponding
2633 * divide method, so it may be slower on a few RISC systems. There are two
2634 * shifts (by 8 or 16 bits) and an addition, versus a single integer divide.
2635 *
2636 * Note that the rounding factors are NOT supposed to be the same! 128 and
2637 * 32768 are correct for the NODIV code; 127 and 32767 are correct for the
2638 * standard method.
2639 *
2640 * [Optimized code by Greg Roelofs and Mark Adler...blame us for bugs. :-) ]
2641 */
2642
2643 /* fg and bg should be in `gamma 1.0' space; alpha is the opacity */
2644
2645 # define png_composite(composite, fg, alpha, bg) \
2646 { png_uint_16 temp = (png_uint_16)((png_uint_16)(fg) * (png_uint_16)(alpha) \
2647 + (png_uint_16)(bg)*(png_uint_16)(255 - \
2648 (png_uint_16)(alpha)) + (png_uint_16)128); \
2649 (composite) = (png_byte)((temp + (temp >> 8)) >> 8); }
2650
2651 # define png_composite_16(composite, fg, alpha, bg) \
2652 { png_uint_32 temp = (png_uint_32)((png_uint_32)(fg) * (png_uint_32)(alpha) \
2653 + (png_uint_32)(bg)*(png_uint_32)(65535L - \
2654 (png_uint_32)(alpha)) + (png_uint_32)32768L); \
2655 (composite) = (png_uint_16)((temp + (temp >> 16)) >> 16); }
2656
2657 #else /* standard method using integer division */
2658
2659 # define png_composite(composite, fg, alpha, bg) \
2660 (composite) = (png_byte)(((png_uint_16)(fg) * (png_uint_16)(alpha) + \
2661 (png_uint_16)(bg) * (png_uint_16)(255 - (png_uint_16)(alpha)) + \
2662 (png_uint_16)127) / 255)
2663
2664 # define png_composite_16(composite, fg, alpha, bg) \
2665 (composite) = (png_uint_16)(((png_uint_32)(fg) * (png_uint_32)(alpha) + \
2666 (png_uint_32)(bg)*(png_uint_32)(65535L - (png_uint_32)(alpha)) + \
2667 (png_uint_32)32767) / (png_uint_32)65535L)
2668
2669 #endif /* PNG_READ_COMPOSITE_NODIV_SUPPORTED */
2670
2671 /* Inline macros to do direct reads of bytes from the input buffer. These
2672 * require that you are using an architecture that uses PNG byte ordering
2673 * (MSB first) and supports unaligned data storage. I think that PowerPC
2674 * in big-endian mode and 680x0 are the only ones that will support this.
2675 * The x86 line of processors definitely do not. The png_get_int_32()
2676 * routine also assumes we are using two's complement format for negative
2677 * values, which is almost certainly true.
2678 */
2679 #if defined(PNG_READ_BIG_ENDIAN_SUPPORTED)
2680 # define png_get_uint_32(buf) ( *((png_uint_32p) (buf)))
2681 # define png_get_uint_16(buf) ( *((png_uint_16p) (buf)))
2682 # define png_get_int_32(buf) ( *((png_int_32p) (buf)))
2683 #else
2684 extern PNG_EXPORT(png_uint_32,png_get_uint_32) PNGARG((png_bytep buf));
2685 extern PNG_EXPORT(png_uint_16,png_get_uint_16) PNGARG((png_bytep buf));
2686 extern PNG_EXPORT(png_int_32,png_get_int_32) PNGARG((png_bytep buf));
2687 #endif /* !PNG_READ_BIG_ENDIAN_SUPPORTED */
2688 extern PNG_EXPORT(png_uint_32,png_get_uint_31)
2689 PNGARG((png_structp png_ptr, png_bytep buf));
2690 /* No png_get_int_16 -- may be added if there's a real need for it. */
2691
2692 /* Place a 32-bit number into a buffer in PNG byte order (big-endian).
2693 */
2694 extern PNG_EXPORT(void,png_save_uint_32)
2695 PNGARG((png_bytep buf, png_uint_32 i));
2696 extern PNG_EXPORT(void,png_save_int_32)
2697 PNGARG((png_bytep buf, png_int_32 i));
2698
2699 /* Place a 16-bit number into a buffer in PNG byte order.
2700 * The parameter is declared unsigned int, not png_uint_16,
2701 * just to avoid potential problems on pre-ANSI C compilers.
2702 */
2703 extern PNG_EXPORT(void,png_save_uint_16)
2704 PNGARG((png_bytep buf, unsigned int i));
2705 /* No png_save_int_16 -- may be added if there's a real need for it. */
2706
2707 /* ************************************************************************* */
2708
2709 /* These next functions are used internally in the code. They generally
2710 * shouldn't be used unless you are writing code to add or replace some
2711 * functionality in libpng. More information about most functions can
2712 * be found in the files where the functions are located.
2713 */
2714
2715
2716 /* Various modes of operation, that are visible to applications because
2717 * they are used for unknown chunk location.
2718 */
2719 #define PNG_HAVE_IHDR 0x01
2720 #define PNG_HAVE_PLTE 0x02
2721 #define PNG_HAVE_IDAT 0x04
2722 #define PNG_AFTER_IDAT 0x08 /* Have complete zlib datastream */
2723 #define PNG_HAVE_IEND 0x10
2724
2725 #if defined(PNG_INTERNAL)
2726
2727 /* More modes of operation. Note that after an init, mode is set to
2728 * zero automatically when the structure is created.
2729 */
2730 #define PNG_HAVE_gAMA 0x20
2731 #define PNG_HAVE_cHRM 0x40
2732 #define PNG_HAVE_sRGB 0x80
2733 #define PNG_HAVE_CHUNK_HEADER 0x100
2734 #define PNG_WROTE_tIME 0x200
2735 #define PNG_WROTE_INFO_BEFORE_PLTE 0x400
2736 #define PNG_BACKGROUND_IS_GRAY 0x800
2737 #define PNG_HAVE_PNG_SIGNATURE 0x1000
2738 #define PNG_HAVE_CHUNK_AFTER_IDAT 0x2000 /* Have another chunk after IDAT */
2739
2740 /* flags for the transformations the PNG library does on the image data */
2741 #define PNG_BGR 0x0001
2742 #define PNG_INTERLACE 0x0002
2743 #define PNG_PACK 0x0004
2744 #define PNG_SHIFT 0x0008
2745 #define PNG_SWAP_BYTES 0x0010
2746 #define PNG_INVERT_MONO 0x0020
2747 #define PNG_DITHER 0x0040
2748 #define PNG_BACKGROUND 0x0080
2749 #define PNG_BACKGROUND_EXPAND 0x0100
2750 /* 0x0200 unused */
2751 #define PNG_16_TO_8 0x0400
2752 #define PNG_RGBA 0x0800
2753 #define PNG_EXPAND 0x1000
2754 #define PNG_GAMMA 0x2000
2755 #define PNG_GRAY_TO_RGB 0x4000
2756 #define PNG_FILLER 0x8000L
2757 #define PNG_PACKSWAP 0x10000L
2758 #define PNG_SWAP_ALPHA 0x20000L
2759 #define PNG_STRIP_ALPHA 0x40000L
2760 #define PNG_INVERT_ALPHA 0x80000L
2761 #define PNG_USER_TRANSFORM 0x100000L
2762 #define PNG_RGB_TO_GRAY_ERR 0x200000L
2763 #define PNG_RGB_TO_GRAY_WARN 0x400000L
2764 #define PNG_RGB_TO_GRAY 0x600000L /* two bits, RGB_TO_GRAY_ERR|WARN */
2765 /* 0x800000L Unused */
2766 #define PNG_ADD_ALPHA 0x1000000L /* Added to libpng-1.2.7 */
2767 #define PNG_EXPAND_tRNS 0x2000000L /* Added to libpng-1.2.9 */
2768 /* 0x4000000L unused */
2769 /* 0x8000000L unused */
2770 /* 0x10000000L unused */
2771 /* 0x20000000L unused */
2772 /* 0x40000000L unused */
2773
2774 /* flags for png_create_struct */
2775 #define PNG_STRUCT_PNG 0x0001
2776 #define PNG_STRUCT_INFO 0x0002
2777
2778 /* Scaling factor for filter heuristic weighting calculations */
2779 #define PNG_WEIGHT_SHIFT 8
2780 #define PNG_WEIGHT_FACTOR (1<<(PNG_WEIGHT_SHIFT))
2781 #define PNG_COST_SHIFT 3
2782 #define PNG_COST_FACTOR (1<<(PNG_COST_SHIFT))
2783
2784 /* flags for the png_ptr->flags rather than declaring a byte for each one */
2785 #define PNG_FLAG_ZLIB_CUSTOM_STRATEGY 0x0001
2786 #define PNG_FLAG_ZLIB_CUSTOM_LEVEL 0x0002
2787 #define PNG_FLAG_ZLIB_CUSTOM_MEM_LEVEL 0x0004
2788 #define PNG_FLAG_ZLIB_CUSTOM_WINDOW_BITS 0x0008
2789 #define PNG_FLAG_ZLIB_CUSTOM_METHOD 0x0010
2790 #define PNG_FLAG_ZLIB_FINISHED 0x0020
2791 #define PNG_FLAG_ROW_INIT 0x0040
2792 #define PNG_FLAG_FILLER_AFTER 0x0080
2793 #define PNG_FLAG_CRC_ANCILLARY_USE 0x0100
2794 #define PNG_FLAG_CRC_ANCILLARY_NOWARN 0x0200
2795 #define PNG_FLAG_CRC_CRITICAL_USE 0x0400
2796 #define PNG_FLAG_CRC_CRITICAL_IGNORE 0x0800
2797 #define PNG_FLAG_FREE_PLTE 0x1000
2798 #define PNG_FLAG_FREE_TRNS 0x2000
2799 #define PNG_FLAG_FREE_HIST 0x4000
2800 #define PNG_FLAG_KEEP_UNKNOWN_CHUNKS 0x8000L
2801 #define PNG_FLAG_KEEP_UNSAFE_CHUNKS 0x10000L
2802 #define PNG_FLAG_LIBRARY_MISMATCH 0x20000L
2803 #define PNG_FLAG_STRIP_ERROR_NUMBERS 0x40000L
2804 #define PNG_FLAG_STRIP_ERROR_TEXT 0x80000L
2805 #define PNG_FLAG_MALLOC_NULL_MEM_OK 0x100000L
2806 #define PNG_FLAG_ADD_ALPHA 0x200000L /* Added to libpng-1.2.8 */
2807 #define PNG_FLAG_STRIP_ALPHA 0x400000L /* Added to libpng-1.2.8 */
2808 /* 0x800000L unused */
2809 /* 0x1000000L unused */
2810 /* 0x2000000L unused */
2811 /* 0x4000000L unused */
2812 /* 0x8000000L unused */
2813 /* 0x10000000L unused */
2814 /* 0x20000000L unused */
2815 /* 0x40000000L unused */
2816
2817 #define PNG_FLAG_CRC_ANCILLARY_MASK (PNG_FLAG_CRC_ANCILLARY_USE | \
2818 PNG_FLAG_CRC_ANCILLARY_NOWARN)
2819
2820 #define PNG_FLAG_CRC_CRITICAL_MASK (PNG_FLAG_CRC_CRITICAL_USE | \
2821 PNG_FLAG_CRC_CRITICAL_IGNORE)
2822
2823 #define PNG_FLAG_CRC_MASK (PNG_FLAG_CRC_ANCILLARY_MASK | \
2824 PNG_FLAG_CRC_CRITICAL_MASK)
2825
2826 /* save typing and make code easier to understand */
2827
2828 #define PNG_COLOR_DIST(c1, c2) (abs((int)((c1).red) - (int)((c2).red)) + \
2829 abs((int)((c1).green) - (int)((c2).green)) + \
2830 abs((int)((c1).blue) - (int)((c2).blue)))
2831
2832 /* Added to libpng-1.2.6 JB */
2833 #define PNG_ROWBYTES(pixel_bits, width) \
2834 ((pixel_bits) >= 8 ? \
2835 ((width) * (((png_uint_32)(pixel_bits)) >> 3)) : \
2836 (( ((width) * ((png_uint_32)(pixel_bits))) + 7) >> 3) )
2837
2838 /* PNG_OUT_OF_RANGE returns true if value is outside the range
2839 ideal-delta..ideal+delta. Each argument is evaluated twice.
2840 "ideal" and "delta" should be constants, normally simple
2841 integers, "value" a variable. Added to libpng-1.2.6 JB */
2842 #define PNG_OUT_OF_RANGE(value, ideal, delta) \
2843 ( (value) < (ideal)-(delta) || (value) > (ideal)+(delta) )
2844
2845 /* variables declared in png.c - only it needs to define PNG_NO_EXTERN */
2846 #if !defined(PNG_NO_EXTERN) || defined(PNG_ALWAYS_EXTERN)
2847 /* place to hold the signature string for a PNG file. */
2848 #ifdef PNG_USE_GLOBAL_ARRAYS
2849 PNG_EXPORT_VAR (PNG_CONST png_byte FARDATA) png_sig[8];
2850 #else
2851 #endif
2852 #endif /* PNG_NO_EXTERN */
2853
2854 /* Constant strings for known chunk types. If you need to add a chunk,
2855 * define the name here, and add an invocation of the macro in png.c and
2856 * wherever it's needed.
2857 */
2858 #define PNG_IHDR png_byte png_IHDR[5] = { 73, 72, 68, 82, '\0'}
2859 #define PNG_IDAT png_byte png_IDAT[5] = { 73, 68, 65, 84, '\0'}
2860 #define PNG_IEND png_byte png_IEND[5] = { 73, 69, 78, 68, '\0'}
2861 #define PNG_PLTE png_byte png_PLTE[5] = { 80, 76, 84, 69, '\0'}
2862 #define PNG_bKGD png_byte png_bKGD[5] = { 98, 75, 71, 68, '\0'}
2863 #define PNG_cHRM png_byte png_cHRM[5] = { 99, 72, 82, 77, '\0'}
2864 #define PNG_gAMA png_byte png_gAMA[5] = {103, 65, 77, 65, '\0'}
2865 #define PNG_hIST png_byte png_hIST[5] = {104, 73, 83, 84, '\0'}
2866 #define PNG_iCCP png_byte png_iCCP[5] = {105, 67, 67, 80, '\0'}
2867 #define PNG_iTXt png_byte png_iTXt[5] = {105, 84, 88, 116, '\0'}
2868 #define PNG_oFFs png_byte png_oFFs[5] = {111, 70, 70, 115, '\0'}
2869 #define PNG_pCAL png_byte png_pCAL[5] = {112, 67, 65, 76, '\0'}
2870 #define PNG_sCAL png_byte png_sCAL[5] = {115, 67, 65, 76, '\0'}
2871 #define PNG_pHYs png_byte png_pHYs[5] = {112, 72, 89, 115, '\0'}
2872 #define PNG_sBIT png_byte png_sBIT[5] = {115, 66, 73, 84, '\0'}
2873 #define PNG_sPLT png_byte png_sPLT[5] = {115, 80, 76, 84, '\0'}
2874 #define PNG_sRGB png_byte png_sRGB[5] = {115, 82, 71, 66, '\0'}
2875 #define PNG_tEXt png_byte png_tEXt[5] = {116, 69, 88, 116, '\0'}
2876 #define PNG_tIME png_byte png_tIME[5] = {116, 73, 77, 69, '\0'}
2877 #define PNG_tRNS png_byte png_tRNS[5] = {116, 82, 78, 83, '\0'}
2878 #define PNG_zTXt png_byte png_zTXt[5] = {122, 84, 88, 116, '\0'}
2879
2880 #ifdef PNG_USE_GLOBAL_ARRAYS
2881 PNG_EXPORT_VAR (png_byte FARDATA) png_IHDR[5];
2882 PNG_EXPORT_VAR (png_byte FARDATA) png_IDAT[5];
2883 PNG_EXPORT_VAR (png_byte FARDATA) png_IEND[5];
2884 PNG_EXPORT_VAR (png_byte FARDATA) png_PLTE[5];
2885 PNG_EXPORT_VAR (png_byte FARDATA) png_bKGD[5];
2886 PNG_EXPORT_VAR (png_byte FARDATA) png_cHRM[5];
2887 PNG_EXPORT_VAR (png_byte FARDATA) png_gAMA[5];
2888 PNG_EXPORT_VAR (png_byte FARDATA) png_hIST[5];
2889 PNG_EXPORT_VAR (png_byte FARDATA) png_iCCP[5];
2890 PNG_EXPORT_VAR (png_byte FARDATA) png_iTXt[5];
2891 PNG_EXPORT_VAR (png_byte FARDATA) png_oFFs[5];
2892 PNG_EXPORT_VAR (png_byte FARDATA) png_pCAL[5];
2893 PNG_EXPORT_VAR (png_byte FARDATA) png_sCAL[5];
2894 PNG_EXPORT_VAR (png_byte FARDATA) png_pHYs[5];
2895 PNG_EXPORT_VAR (png_byte FARDATA) png_sBIT[5];
2896 PNG_EXPORT_VAR (png_byte FARDATA) png_sPLT[5];
2897 PNG_EXPORT_VAR (png_byte FARDATA) png_sRGB[5];
2898 PNG_EXPORT_VAR (png_byte FARDATA) png_tEXt[5];
2899 PNG_EXPORT_VAR (png_byte FARDATA) png_tIME[5];
2900 PNG_EXPORT_VAR (png_byte FARDATA) png_tRNS[5];
2901 PNG_EXPORT_VAR (png_byte FARDATA) png_zTXt[5];
2902 #endif /* PNG_USE_GLOBAL_ARRAYS */
2903
2904 #if defined(PNG_1_0_X) || defined (PNG_1_2_X)
2905 /* Initialize png_ptr struct for reading, and allocate any other memory.
2906 * (old interface - DEPRECATED - use png_create_read_struct instead).
2907 */
2908 extern PNG_EXPORT(void,png_read_init) PNGARG((png_structp png_ptr));
2909 #undef png_read_init
2910 #define png_read_init(png_ptr) png_read_init_3(&png_ptr, \
2911 PNG_LIBPNG_VER_STRING, png_sizeof(png_struct));
2912 #endif
2913
2914 extern PNG_EXPORT(void,png_read_init_3) PNGARG((png_structpp ptr_ptr,
2915 png_const_charp user_png_ver, png_size_t png_struct_size));
2916 #if defined(PNG_1_0_X) || defined (PNG_1_2_X)
2917 extern PNG_EXPORT(void,png_read_init_2) PNGARG((png_structp png_ptr,
2918 png_const_charp user_png_ver, png_size_t png_struct_size, png_size_t
2919 png_info_size));
2920 #endif
2921
2922 #if defined(PNG_1_0_X) || defined (PNG_1_2_X)
2923 /* Initialize png_ptr struct for writing, and allocate any other memory.
2924 * (old interface - DEPRECATED - use png_create_write_struct instead).
2925 */
2926 extern PNG_EXPORT(void,png_write_init) PNGARG((png_structp png_ptr));
2927 #undef png_write_init
2928 #define png_write_init(png_ptr) png_write_init_3(&png_ptr, \
2929 PNG_LIBPNG_VER_STRING, png_sizeof(png_struct));
2930 #endif
2931
2932 extern PNG_EXPORT(void,png_write_init_3) PNGARG((png_structpp ptr_ptr,
2933 png_const_charp user_png_ver, png_size_t png_struct_size));
2934 extern PNG_EXPORT(void,png_write_init_2) PNGARG((png_structp png_ptr,
2935 png_const_charp user_png_ver, png_size_t png_struct_size, png_size_t
2936 png_info_size));
2937
2938 /* Allocate memory for an internal libpng struct */
2939 PNG_EXTERN png_voidp png_create_struct PNGARG((int type));
2940
2941 /* Free memory from internal libpng struct */
2942 PNG_EXTERN void png_destroy_struct PNGARG((png_voidp struct_ptr));
2943
2944 PNG_EXTERN png_voidp png_create_struct_2 PNGARG((int type, png_malloc_ptr
2945 malloc_fn, png_voidp mem_ptr));
2946 PNG_EXTERN void png_destroy_struct_2 PNGARG((png_voidp struct_ptr,
2947 png_free_ptr free_fn, png_voidp mem_ptr));
2948
2949 /* Free any memory that info_ptr points to and reset struct. */
2950 PNG_EXTERN void png_info_destroy PNGARG((png_structp png_ptr,
2951 png_infop info_ptr));
2952
2953 #ifndef PNG_1_0_X
2954 /* Function to allocate memory for zlib. */
2955 PNG_EXTERN voidpf png_zalloc PNGARG((voidpf png_ptr, uInt items, uInt size));
2956
2957 /* Function to free memory for zlib */
2958 PNG_EXTERN void png_zfree PNGARG((voidpf png_ptr, voidpf ptr));
2959
2960 #ifdef PNG_SIZE_T
2961 /* Function to convert a sizeof an item to png_sizeof item */
2962 PNG_EXTERN png_size_t PNGAPI png_convert_size PNGARG((size_t size));
2963 #endif
2964
2965 /* Next four functions are used internally as callbacks. PNGAPI is required
2966 * but not PNG_EXPORT. PNGAPI added at libpng version 1.2.3. */
2967
2968 PNG_EXTERN void PNGAPI png_default_read_data PNGARG((png_structp png_ptr,
2969 png_bytep data, png_size_t length));
2970
2971 #ifdef PNG_PROGRESSIVE_READ_SUPPORTED
2972 PNG_EXTERN void PNGAPI png_push_fill_buffer PNGARG((png_structp png_ptr,
2973 png_bytep buffer, png_size_t length));
2974 #endif
2975
2976 PNG_EXTERN void PNGAPI png_default_write_data PNGARG((png_structp png_ptr,
2977 png_bytep data, png_size_t length));
2978
2979 #if defined(PNG_WRITE_FLUSH_SUPPORTED)
2980 #if !defined(PNG_NO_STDIO)
2981 PNG_EXTERN void PNGAPI png_default_flush PNGARG((png_structp png_ptr));
2982 #endif
2983 #endif
2984 #else /* PNG_1_0_X */
2985 #ifdef PNG_PROGRESSIVE_READ_SUPPORTED
2986 PNG_EXTERN void png_push_fill_buffer PNGARG((png_structp png_ptr,
2987 png_bytep buffer, png_size_t length));
2988 #endif
2989 #endif /* PNG_1_0_X */
2990
2991 /* Reset the CRC variable */
2992 PNG_EXTERN void png_reset_crc PNGARG((png_structp png_ptr));
2993
2994 /* Write the "data" buffer to whatever output you are using. */
2995 PNG_EXTERN void png_write_data PNGARG((png_structp png_ptr, png_bytep data,
2996 png_size_t length));
2997
2998 /* Read data from whatever input you are using into the "data" buffer */
2999 PNG_EXTERN void png_read_data PNGARG((png_structp png_ptr, png_bytep data,
3000 png_size_t length));
3001
3002 /* Read bytes into buf, and update png_ptr->crc */
3003 PNG_EXTERN void png_crc_read PNGARG((png_structp png_ptr, png_bytep buf,
3004 png_size_t length));
3005
3006 /* Decompress data in a chunk that uses compression */
3007 #if defined(PNG_zTXt_SUPPORTED) || defined(PNG_iTXt_SUPPORTED) || \
3008 defined(PNG_iCCP_SUPPORTED) || defined(PNG_sPLT_SUPPORTED)
3009 PNG_EXTERN png_charp png_decompress_chunk PNGARG((png_structp png_ptr,
3010 int comp_type, png_charp chunkdata, png_size_t chunklength,
3011 png_size_t prefix_length, png_size_t *data_length));
3012 #endif
3013
3014 /* Read "skip" bytes, read the file crc, and (optionally) verify png_ptr->crc */
3015 PNG_EXTERN int png_crc_finish PNGARG((png_structp png_ptr, png_uint_32 skip));
3016
3017 /* Read the CRC from the file and compare it to the libpng calculated CRC */
3018 PNG_EXTERN int png_crc_error PNGARG((png_structp png_ptr));
3019
3020 /* Calculate the CRC over a section of data. Note that we are only
3021 * passing a maximum of 64K on systems that have this as a memory limit,
3022 * since this is the maximum buffer size we can specify.
3023 */
3024 PNG_EXTERN void png_calculate_crc PNGARG((png_structp png_ptr, png_bytep ptr,
3025 png_size_t length));
3026
3027 #if defined(PNG_WRITE_FLUSH_SUPPORTED)
3028 PNG_EXTERN void png_flush PNGARG((png_structp png_ptr));
3029 #endif
3030
3031 /* simple function to write the signature */
3032 PNG_EXTERN void png_write_sig PNGARG((png_structp png_ptr));
3033
3034 /* write various chunks */
3035
3036 /* Write the IHDR chunk, and update the png_struct with the necessary
3037 * information.
3038 */
3039 PNG_EXTERN void png_write_IHDR PNGARG((png_structp png_ptr, png_uint_32 width,
3040 png_uint_32 height,
3041 int bit_depth, int color_type, int compression_method, int filter_method,
3042 int interlace_method));
3043
3044 PNG_EXTERN void png_write_PLTE PNGARG((png_structp png_ptr, png_colorp palette,
3045 png_uint_32 num_pal));
3046
3047 PNG_EXTERN void png_write_IDAT PNGARG((png_structp png_ptr, png_bytep data,
3048 png_size_t length));
3049
3050 PNG_EXTERN void png_write_IEND PNGARG((png_structp png_ptr));
3051
3052 #if defined(PNG_WRITE_gAMA_SUPPORTED)
3053 #ifdef PNG_FLOATING_POINT_SUPPORTED
3054 PNG_EXTERN void png_write_gAMA PNGARG((png_structp png_ptr, double file_gamma));
3055 #endif
3056 #ifdef PNG_FIXED_POINT_SUPPORTED
3057 PNG_EXTERN void png_write_gAMA_fixed PNGARG((png_structp png_ptr, png_fixed_point
3058 file_gamma));
3059 #endif
3060 #endif
3061
3062 #if defined(PNG_WRITE_sBIT_SUPPORTED)
3063 PNG_EXTERN void png_write_sBIT PNGARG((png_structp png_ptr, png_color_8p sbit,
3064 int color_type));
3065 #endif
3066
3067 #if defined(PNG_WRITE_cHRM_SUPPORTED)
3068 #ifdef PNG_FLOATING_POINT_SUPPORTED
3069 PNG_EXTERN void png_write_cHRM PNGARG((png_structp png_ptr,
3070 double white_x, double white_y,
3071 double red_x, double red_y, double green_x, double green_y,
3072 double blue_x, double blue_y));
3073 #endif
3074 #ifdef PNG_FIXED_POINT_SUPPORTED
3075 PNG_EXTERN void png_write_cHRM_fixed PNGARG((png_structp png_ptr,
3076 png_fixed_point int_white_x, png_fixed_point int_white_y,
3077 png_fixed_point int_red_x, png_fixed_point int_red_y, png_fixed_point
3078 int_green_x, png_fixed_point int_green_y, png_fixed_point int_blue_x,
3079 png_fixed_point int_blue_y));
3080 #endif
3081 #endif
3082
3083 #if defined(PNG_WRITE_sRGB_SUPPORTED)
3084 PNG_EXTERN void png_write_sRGB PNGARG((png_structp png_ptr,
3085 int intent));
3086 #endif
3087
3088 #if defined(PNG_WRITE_iCCP_SUPPORTED)
3089 PNG_EXTERN void png_write_iCCP PNGARG((png_structp png_ptr,
3090 png_charp name, int compression_type,
3091 png_charp profile, int proflen));
3092 /* Note to maintainer: profile should be png_bytep */
3093 #endif
3094
3095 #if defined(PNG_WRITE_sPLT_SUPPORTED)
3096 PNG_EXTERN void png_write_sPLT PNGARG((png_structp png_ptr,
3097 png_sPLT_tp palette));
3098 #endif
3099
3100 #if defined(PNG_WRITE_tRNS_SUPPORTED)
3101 PNG_EXTERN void png_write_tRNS PNGARG((png_structp png_ptr, png_bytep trans,
3102 png_color_16p values, int number, int color_type));
3103 #endif
3104
3105 #if defined(PNG_WRITE_bKGD_SUPPORTED)
3106 PNG_EXTERN void png_write_bKGD PNGARG((png_structp png_ptr,
3107 png_color_16p values, int color_type));
3108 #endif
3109
3110 #if defined(PNG_WRITE_hIST_SUPPORTED)
3111 PNG_EXTERN void png_write_hIST PNGARG((png_structp png_ptr, png_uint_16p hist,
3112 int num_hist));
3113 #endif
3114
3115 #if defined(PNG_WRITE_TEXT_SUPPORTED) || defined(PNG_WRITE_pCAL_SUPPORTED) || \
3116 defined(PNG_WRITE_iCCP_SUPPORTED) || defined(PNG_WRITE_sPLT_SUPPORTED)
3117 PNG_EXTERN png_size_t png_check_keyword PNGARG((png_structp png_ptr,
3118 png_charp key, png_charpp new_key));
3119 #endif
3120
3121 #if defined(PNG_WRITE_tEXt_SUPPORTED)
3122 PNG_EXTERN void png_write_tEXt PNGARG((png_structp png_ptr, png_charp key,
3123 png_charp text, png_size_t text_len));
3124 #endif
3125
3126 #if defined(PNG_WRITE_zTXt_SUPPORTED)
3127 PNG_EXTERN void png_write_zTXt PNGARG((png_structp png_ptr, png_charp key,
3128 png_charp text, png_size_t text_len, int compression));
3129 #endif
3130
3131 #if defined(PNG_WRITE_iTXt_SUPPORTED)
3132 PNG_EXTERN void png_write_iTXt PNGARG((png_structp png_ptr,
3133 int compression, png_charp key, png_charp lang, png_charp lang_key,
3134 png_charp text));
3135 #endif
3136
3137 #if defined(PNG_TEXT_SUPPORTED) /* Added at version 1.0.14 and 1.2.4 */
3138 PNG_EXTERN int png_set_text_2 PNGARG((png_structp png_ptr,
3139 png_infop info_ptr, png_textp text_ptr, int num_text));
3140 #endif
3141
3142 #if defined(PNG_WRITE_oFFs_SUPPORTED)
3143 PNG_EXTERN void png_write_oFFs PNGARG((png_structp png_ptr,
3144 png_int_32 x_offset, png_int_32 y_offset, int unit_type));
3145 #endif
3146
3147 #if defined(PNG_WRITE_pCAL_SUPPORTED)
3148 PNG_EXTERN void png_write_pCAL PNGARG((png_structp png_ptr, png_charp purpose,
3149 png_int_32 X0, png_int_32 X1, int type, int nparams,
3150 png_charp units, png_charpp params));
3151 #endif
3152
3153 #if defined(PNG_WRITE_pHYs_SUPPORTED)
3154 PNG_EXTERN void png_write_pHYs PNGARG((png_structp png_ptr,
3155 png_uint_32 x_pixels_per_unit, png_uint_32 y_pixels_per_unit,
3156 int unit_type));
3157 #endif
3158
3159 #if defined(PNG_WRITE_tIME_SUPPORTED)
3160 PNG_EXTERN void png_write_tIME PNGARG((png_structp png_ptr,
3161 png_timep mod_time));
3162 #endif
3163
3164 #if defined(PNG_WRITE_sCAL_SUPPORTED)
3165 #if defined(PNG_FLOATING_POINT_SUPPORTED) && !defined(PNG_NO_STDIO)
3166 PNG_EXTERN void png_write_sCAL PNGARG((png_structp png_ptr,
3167 int unit, double width, double height));
3168 #else
3169 #ifdef PNG_FIXED_POINT_SUPPORTED
3170 PNG_EXTERN void png_write_sCAL_s PNGARG((png_structp png_ptr,
3171 int unit, png_charp width, png_charp height));
3172 #endif
3173 #endif
3174 #endif
3175
3176 /* Called when finished processing a row of data */
3177 PNG_EXTERN void png_write_finish_row PNGARG((png_structp png_ptr));
3178
3179 /* Internal use only. Called before first row of data */
3180 PNG_EXTERN void png_write_start_row PNGARG((png_structp png_ptr));
3181
3182 #if defined(PNG_READ_GAMMA_SUPPORTED)
3183 PNG_EXTERN void png_build_gamma_table PNGARG((png_structp png_ptr));
3184 #endif
3185
3186 /* combine a row of data, dealing with alpha, etc. if requested */
3187 PNG_EXTERN void png_combine_row PNGARG((png_structp png_ptr, png_bytep row,
3188 int mask));
3189
3190 #if defined(PNG_READ_INTERLACING_SUPPORTED)
3191 /* expand an interlaced row */
3192 /* OLD pre-1.0.9 interface:
3193 PNG_EXTERN void png_do_read_interlace PNGARG((png_row_infop row_info,
3194 png_bytep row, int pass, png_uint_32 transformations));
3195 */
3196 PNG_EXTERN void png_do_read_interlace PNGARG((png_structp png_ptr));
3197 #endif
3198
3199 /* GRR TO DO (2.0 or whenever): simplify other internal calling interfaces */
3200
3201 #if defined(PNG_WRITE_INTERLACING_SUPPORTED)
3202 /* grab pixels out of a row for an interlaced pass */
3203 PNG_EXTERN void png_do_write_interlace PNGARG((png_row_infop row_info,
3204 png_bytep row, int pass));
3205 #endif
3206
3207 /* unfilter a row */
3208 PNG_EXTERN void png_read_filter_row PNGARG((png_structp png_ptr,
3209 png_row_infop row_info, png_bytep row, png_bytep prev_row, int filter));
3210
3211 /* Choose the best filter to use and filter the row data */
3212 PNG_EXTERN void png_write_find_filter PNGARG((png_structp png_ptr,
3213 png_row_infop row_info));
3214
3215 /* Write out the filtered row. */
3216 PNG_EXTERN void png_write_filtered_row PNGARG((png_structp png_ptr,
3217 png_bytep filtered_row));
3218 /* finish a row while reading, dealing with interlacing passes, etc. */
3219 PNG_EXTERN void png_read_finish_row PNGARG((png_structp png_ptr));
3220
3221 /* initialize the row buffers, etc. */
3222 PNG_EXTERN void png_read_start_row PNGARG((png_structp png_ptr));
3223 /* optional call to update the users info structure */
3224 PNG_EXTERN void png_read_transform_info PNGARG((png_structp png_ptr,
3225 png_infop info_ptr));
3226
3227 /* these are the functions that do the transformations */
3228 #if defined(PNG_READ_FILLER_SUPPORTED)
3229 PNG_EXTERN void png_do_read_filler PNGARG((png_row_infop row_info,
3230 png_bytep row, png_uint_32 filler, png_uint_32 flags));
3231 #endif
3232
3233 #if defined(PNG_READ_SWAP_ALPHA_SUPPORTED)
3234 PNG_EXTERN void png_do_read_swap_alpha PNGARG((png_row_infop row_info,
3235 png_bytep row));
3236 #endif
3237
3238 #if defined(PNG_WRITE_SWAP_ALPHA_SUPPORTED)
3239 PNG_EXTERN void png_do_write_swap_alpha PNGARG((png_row_infop row_info,
3240 png_bytep row));
3241 #endif
3242
3243 #if defined(PNG_READ_INVERT_ALPHA_SUPPORTED)
3244 PNG_EXTERN void png_do_read_invert_alpha PNGARG((png_row_infop row_info,
3245 png_bytep row));
3246 #endif
3247
3248 #if defined(PNG_WRITE_INVERT_ALPHA_SUPPORTED)
3249 PNG_EXTERN void png_do_write_invert_alpha PNGARG((png_row_infop row_info,
3250 png_bytep row));
3251 #endif
3252
3253 #if defined(PNG_WRITE_FILLER_SUPPORTED) || \
3254 defined(PNG_READ_STRIP_ALPHA_SUPPORTED)
3255 PNG_EXTERN void png_do_strip_filler PNGARG((png_row_infop row_info,
3256 png_bytep row, png_uint_32 flags));
3257 #endif
3258
3259 #if defined(PNG_READ_SWAP_SUPPORTED) || defined(PNG_WRITE_SWAP_SUPPORTED)
3260 PNG_EXTERN void png_do_swap PNGARG((png_row_infop row_info, png_bytep row));
3261 #endif
3262
3263 #if defined(PNG_READ_PACKSWAP_SUPPORTED) || defined(PNG_WRITE_PACKSWAP_SUPPORTED)
3264 PNG_EXTERN void png_do_packswap PNGARG((png_row_infop row_info, png_bytep row));
3265 #endif
3266
3267 #if defined(PNG_READ_RGB_TO_GRAY_SUPPORTED)
3268 PNG_EXTERN int png_do_rgb_to_gray PNGARG((png_structp png_ptr, png_row_infop
3269 row_info, png_bytep row));
3270 #endif
3271
3272 #if defined(PNG_READ_GRAY_TO_RGB_SUPPORTED)
3273 PNG_EXTERN void png_do_gray_to_rgb PNGARG((png_row_infop row_info,
3274 png_bytep row));
3275 #endif
3276
3277 #if defined(PNG_READ_PACK_SUPPORTED)
3278 PNG_EXTERN void png_do_unpack PNGARG((png_row_infop row_info, png_bytep row));
3279 #endif
3280
3281 #if defined(PNG_READ_SHIFT_SUPPORTED)
3282 PNG_EXTERN void png_do_unshift PNGARG((png_row_infop row_info, png_bytep row,
3283 png_color_8p sig_bits));
3284 #endif
3285
3286 #if defined(PNG_READ_INVERT_SUPPORTED) || defined(PNG_WRITE_INVERT_SUPPORTED)
3287 PNG_EXTERN void png_do_invert PNGARG((png_row_infop row_info, png_bytep row));
3288 #endif
3289
3290 #if defined(PNG_READ_16_TO_8_SUPPORTED)
3291 PNG_EXTERN void png_do_chop PNGARG((png_row_infop row_info, png_bytep row));
3292 #endif
3293
3294 #if defined(PNG_READ_DITHER_SUPPORTED)
3295 PNG_EXTERN void png_do_dither PNGARG((png_row_infop row_info,
3296 png_bytep row, png_bytep palette_lookup, png_bytep dither_lookup));
3297
3298 # if defined(PNG_CORRECT_PALETTE_SUPPORTED)
3299 PNG_EXTERN void png_correct_palette PNGARG((png_structp png_ptr,
3300 png_colorp palette, int num_palette));
3301 # endif
3302 #endif
3303
3304 #if defined(PNG_READ_BGR_SUPPORTED) || defined(PNG_WRITE_BGR_SUPPORTED)
3305 PNG_EXTERN void png_do_bgr PNGARG((png_row_infop row_info, png_bytep row));
3306 #endif
3307
3308 #if defined(PNG_WRITE_PACK_SUPPORTED)
3309 PNG_EXTERN void png_do_pack PNGARG((png_row_infop row_info,
3310 png_bytep row, png_uint_32 bit_depth));
3311 #endif
3312
3313 #if defined(PNG_WRITE_SHIFT_SUPPORTED)
3314 PNG_EXTERN void png_do_shift PNGARG((png_row_infop row_info, png_bytep row,
3315 png_color_8p bit_depth));
3316 #endif
3317
3318 #if defined(PNG_READ_BACKGROUND_SUPPORTED)
3319 #if defined(PNG_READ_GAMMA_SUPPORTED)
3320 PNG_EXTERN void png_do_background PNGARG((png_row_infop row_info, png_bytep row,
3321 png_color_16p trans_values, png_color_16p background,
3322 png_color_16p background_1,
3323 png_bytep gamma_table, png_bytep gamma_from_1, png_bytep gamma_to_1,
3324 png_uint_16pp gamma_16, png_uint_16pp gamma_16_from_1,
3325 png_uint_16pp gamma_16_to_1, int gamma_shift));
3326 #else
3327 PNG_EXTERN void png_do_background PNGARG((png_row_infop row_info, png_bytep row,
3328 png_color_16p trans_values, png_color_16p background));
3329 #endif
3330 #endif
3331
3332 #if defined(PNG_READ_GAMMA_SUPPORTED)
3333 PNG_EXTERN void png_do_gamma PNGARG((png_row_infop row_info, png_bytep row,
3334 png_bytep gamma_table, png_uint_16pp gamma_16_table,
3335 int gamma_shift));
3336 #endif
3337
3338 #if defined(PNG_READ_EXPAND_SUPPORTED)
3339 PNG_EXTERN void png_do_expand_palette PNGARG((png_row_infop row_info,
3340 png_bytep row, png_colorp palette, png_bytep trans, int num_trans));
3341 PNG_EXTERN void png_do_expand PNGARG((png_row_infop row_info,
3342 png_bytep row, png_color_16p trans_value));
3343 #endif
3344
3345 /* The following decodes the appropriate chunks, and does error correction,
3346 * then calls the appropriate callback for the chunk if it is valid.
3347 */
3348
3349 /* decode the IHDR chunk */
3350 PNG_EXTERN void png_handle_IHDR PNGARG((png_structp png_ptr, png_infop info_ptr,
3351 png_uint_32 length));
3352 PNG_EXTERN void png_handle_PLTE PNGARG((png_structp png_ptr, png_infop info_ptr,
3353 png_uint_32 length));
3354 PNG_EXTERN void png_handle_IEND PNGARG((png_structp png_ptr, png_infop info_ptr,
3355 png_uint_32 length));
3356
3357 #if defined(PNG_READ_bKGD_SUPPORTED)
3358 PNG_EXTERN void png_handle_bKGD PNGARG((png_structp png_ptr, png_infop info_ptr,
3359 png_uint_32 length));
3360 #endif
3361
3362 #if defined(PNG_READ_cHRM_SUPPORTED)
3363 PNG_EXTERN void png_handle_cHRM PNGARG((png_structp png_ptr, png_infop info_ptr,
3364 png_uint_32 length));
3365 #endif
3366
3367 #if defined(PNG_READ_gAMA_SUPPORTED)
3368 PNG_EXTERN void png_handle_gAMA PNGARG((png_structp png_ptr, png_infop info_ptr,
3369 png_uint_32 length));
3370 #endif
3371
3372 #if defined(PNG_READ_hIST_SUPPORTED)
3373 PNG_EXTERN void png_handle_hIST PNGARG((png_structp png_ptr, png_infop info_ptr,
3374 png_uint_32 length));
3375 #endif
3376
3377 #if defined(PNG_READ_iCCP_SUPPORTED)
3378 extern void png_handle_iCCP PNGARG((png_structp png_ptr, png_infop info_ptr,
3379 png_uint_32 length));
3380 #endif /* PNG_READ_iCCP_SUPPORTED */
3381
3382 #if defined(PNG_READ_iTXt_SUPPORTED)
3383 PNG_EXTERN void png_handle_iTXt PNGARG((png_structp png_ptr, png_infop info_ptr,
3384 png_uint_32 length));
3385 #endif
3386
3387 #if defined(PNG_READ_oFFs_SUPPORTED)
3388 PNG_EXTERN void png_handle_oFFs PNGARG((png_structp png_ptr, png_infop info_ptr,
3389 png_uint_32 length));
3390 #endif
3391
3392 #if defined(PNG_READ_pCAL_SUPPORTED)
3393 PNG_EXTERN void png_handle_pCAL PNGARG((png_structp png_ptr, png_infop info_ptr,
3394 png_uint_32 length));
3395 #endif
3396
3397 #if defined(PNG_READ_pHYs_SUPPORTED)
3398 PNG_EXTERN void png_handle_pHYs PNGARG((png_structp png_ptr, png_infop info_ptr,
3399 png_uint_32 length));
3400 #endif
3401
3402 #if defined(PNG_READ_sBIT_SUPPORTED)
3403 PNG_EXTERN void png_handle_sBIT PNGARG((png_structp png_ptr, png_infop info_ptr,
3404 png_uint_32 length));
3405 #endif
3406
3407 #if defined(PNG_READ_sCAL_SUPPORTED)
3408 PNG_EXTERN void png_handle_sCAL PNGARG((png_structp png_ptr, png_infop info_ptr,
3409 png_uint_32 length));
3410 #endif
3411
3412 #if defined(PNG_READ_sPLT_SUPPORTED)
3413 extern void png_handle_sPLT PNGARG((png_structp png_ptr, png_infop info_ptr,
3414 png_uint_32 length));
3415 #endif /* PNG_READ_sPLT_SUPPORTED */
3416
3417 #if defined(PNG_READ_sRGB_SUPPORTED)
3418 PNG_EXTERN void png_handle_sRGB PNGARG((png_structp png_ptr, png_infop info_ptr,
3419 png_uint_32 length));
3420 #endif
3421
3422 #if defined(PNG_READ_tEXt_SUPPORTED)
3423 PNG_EXTERN void png_handle_tEXt PNGARG((png_structp png_ptr, png_infop info_ptr,
3424 png_uint_32 length));
3425 #endif
3426
3427 #if defined(PNG_READ_tIME_SUPPORTED)
3428 PNG_EXTERN void png_handle_tIME PNGARG((png_structp png_ptr, png_infop info_ptr,
3429 png_uint_32 length));
3430 #endif
3431
3432 #if defined(PNG_READ_tRNS_SUPPORTED)
3433 PNG_EXTERN void png_handle_tRNS PNGARG((png_structp png_ptr, png_infop info_ptr,
3434 png_uint_32 length));
3435 #endif
3436
3437 #if defined(PNG_READ_zTXt_SUPPORTED)
3438 PNG_EXTERN void png_handle_zTX