comparison ext/libpng-1.2.29/png.h @ 0:4a0efb7baf70

* Datasets becomes the new trunk and retires after that :-)
author mvbarracuda@33b003aa-7bff-0310-803a-e67f0ece8222
date Sun, 29 Jun 2008 18:44:17 +0000
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children
comparison
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-1:000000000000 0:4a0efb7baf70
1 /* png.h - header file for PNG reference library
2 *
3 * libpng version 1.2.29 - May 8, 2008
4 * Copyright (c) 1998-2008 Glenn Randers-Pehrson
5 * (Version 0.96 Copyright (c) 1996, 1997 Andreas Dilger)
6 * (Version 0.88 Copyright (c) 1995, 1996 Guy Eric Schalnat, Group 42, Inc.)
7 *
8 * Authors and maintainers:
9 * libpng versions 0.71, May 1995, through 0.88, January 1996: Guy Schalnat
10 * libpng versions 0.89c, June 1996, through 0.96, May 1997: Andreas Dilger
11 * libpng versions 0.97, January 1998, through 1.2.29 - May 8, 2008: Glenn
12 * See also "Contributing Authors", below.
13 *
14 * Note about libpng version numbers:
15 *
16 * Due to various miscommunications, unforeseen code incompatibilities
17 * and occasional factors outside the authors' control, version numbering
18 * on the library has not always been consistent and straightforward.
19 * The following table summarizes matters since version 0.89c, which was
20 * the first widely used release:
21 *
22 * source png.h png.h shared-lib
23 * version string int version
24 * ------- ------ ----- ----------
25 * 0.89c "1.0 beta 3" 0.89 89 1.0.89
26 * 0.90 "1.0 beta 4" 0.90 90 0.90 [should have been 2.0.90]
27 * 0.95 "1.0 beta 5" 0.95 95 0.95 [should have been 2.0.95]
28 * 0.96 "1.0 beta 6" 0.96 96 0.96 [should have been 2.0.96]
29 * 0.97b "1.00.97 beta 7" 1.00.97 97 1.0.1 [should have been 2.0.97]
30 * 0.97c 0.97 97 2.0.97
31 * 0.98 0.98 98 2.0.98
32 * 0.99 0.99 98 2.0.99
33 * 0.99a-m 0.99 99 2.0.99
34 * 1.00 1.00 100 2.1.0 [100 should be 10000]
35 * 1.0.0 (from here on, the 100 2.1.0 [100 should be 10000]
36 * 1.0.1 png.h string is 10001 2.1.0
37 * 1.0.1a-e identical to the 10002 from here on, the shared library
38 * 1.0.2 source version) 10002 is 2.V where V is the source code
39 * 1.0.2a-b 10003 version, except as noted.
40 * 1.0.3 10003
41 * 1.0.3a-d 10004
42 * 1.0.4 10004
43 * 1.0.4a-f 10005
44 * 1.0.5 (+ 2 patches) 10005
45 * 1.0.5a-d 10006
46 * 1.0.5e-r 10100 (not source compatible)
47 * 1.0.5s-v 10006 (not binary compatible)
48 * 1.0.6 (+ 3 patches) 10006 (still binary incompatible)
49 * 1.0.6d-f 10007 (still binary incompatible)
50 * 1.0.6g 10007
51 * 1.0.6h 10007 10.6h (testing xy.z so-numbering)
52 * 1.0.6i 10007 10.6i
53 * 1.0.6j 10007 2.1.0.6j (incompatible with 1.0.0)
54 * 1.0.7beta11-14 DLLNUM 10007 2.1.0.7beta11-14 (binary compatible)
55 * 1.0.7beta15-18 1 10007 2.1.0.7beta15-18 (binary compatible)
56 * 1.0.7rc1-2 1 10007 2.1.0.7rc1-2 (binary compatible)
57 * 1.0.7 1 10007 (still compatible)
58 * 1.0.8beta1-4 1 10008 2.1.0.8beta1-4
59 * 1.0.8rc1 1 10008 2.1.0.8rc1
60 * 1.0.8 1 10008 2.1.0.8
61 * 1.0.9beta1-6 1 10009 2.1.0.9beta1-6
62 * 1.0.9rc1 1 10009 2.1.0.9rc1
63 * 1.0.9beta7-10 1 10009 2.1.0.9beta7-10
64 * 1.0.9rc2 1 10009 2.1.0.9rc2
65 * 1.0.9 1 10009 2.1.0.9
66 * 1.0.10beta1 1 10010 2.1.0.10beta1
67 * 1.0.10rc1 1 10010 2.1.0.10rc1
68 * 1.0.10 1 10010 2.1.0.10
69 * 1.0.11beta1-3 1 10011 2.1.0.11beta1-3
70 * 1.0.11rc1 1 10011 2.1.0.11rc1
71 * 1.0.11 1 10011 2.1.0.11
72 * 1.0.12beta1-2 2 10012 2.1.0.12beta1-2
73 * 1.0.12rc1 2 10012 2.1.0.12rc1
74 * 1.0.12 2 10012 2.1.0.12
75 * 1.1.0a-f - 10100 2.1.1.0a-f (branch abandoned)
76 * 1.2.0beta1-2 2 10200 2.1.2.0beta1-2
77 * 1.2.0beta3-5 3 10200 3.1.2.0beta3-5
78 * 1.2.0rc1 3 10200 3.1.2.0rc1
79 * 1.2.0 3 10200 3.1.2.0
80 * 1.2.1beta1-4 3 10201 3.1.2.1beta1-4
81 * 1.2.1rc1-2 3 10201 3.1.2.1rc1-2
82 * 1.2.1 3 10201 3.1.2.1
83 * 1.2.2beta1-6 12 10202 12.so.0.1.2.2beta1-6
84 * 1.0.13beta1 10 10013 10.so.0.1.0.13beta1
85 * 1.0.13rc1 10 10013 10.so.0.1.0.13rc1
86 * 1.2.2rc1 12 10202 12.so.0.1.2.2rc1
87 * 1.0.13 10 10013 10.so.0.1.0.13
88 * 1.2.2 12 10202 12.so.0.1.2.2
89 * 1.2.3rc1-6 12 10203 12.so.0.1.2.3rc1-6
90 * 1.2.3 12 10203 12.so.0.1.2.3
91 * 1.2.4beta1-3 13 10204 12.so.0.1.2.4beta1-3
92 * 1.0.14rc1 13 10014 10.so.0.1.0.14rc1
93 * 1.2.4rc1 13 10204 12.so.0.1.2.4rc1
94 * 1.0.14 10 10014 10.so.0.1.0.14
95 * 1.2.4 13 10204 12.so.0.1.2.4
96 * 1.2.5beta1-2 13 10205 12.so.0.1.2.5beta1-2
97 * 1.0.15rc1-3 10 10015 10.so.0.1.0.15rc1-3
98 * 1.2.5rc1-3 13 10205 12.so.0.1.2.5rc1-3
99 * 1.0.15 10 10015 10.so.0.1.0.15
100 * 1.2.5 13 10205 12.so.0.1.2.5
101 * 1.2.6beta1-4 13 10206 12.so.0.1.2.6beta1-4
102 * 1.0.16 10 10016 10.so.0.1.0.16
103 * 1.2.6 13 10206 12.so.0.1.2.6
104 * 1.2.7beta1-2 13 10207 12.so.0.1.2.7beta1-2
105 * 1.0.17rc1 10 10017 10.so.0.1.0.17rc1
106 * 1.2.7rc1 13 10207 12.so.0.1.2.7rc1
107 * 1.0.17 10 10017 10.so.0.1.0.17
108 * 1.2.7 13 10207 12.so.0.1.2.7
109 * 1.2.8beta1-5 13 10208 12.so.0.1.2.8beta1-5
110 * 1.0.18rc1-5 10 10018 10.so.0.1.0.18rc1-5
111 * 1.2.8rc1-5 13 10208 12.so.0.1.2.8rc1-5
112 * 1.0.18 10 10018 10.so.0.1.0.18
113 * 1.2.8 13 10208 12.so.0.1.2.8
114 * 1.2.9beta1-3 13 10209 12.so.0.1.2.9beta1-3
115 * 1.2.9beta4-11 13 10209 12.so.0.9[.0]
116 * 1.2.9rc1 13 10209 12.so.0.9[.0]
117 * 1.2.9 13 10209 12.so.0.9[.0]
118 * 1.2.10beta1-8 13 10210 12.so.0.10[.0]
119 * 1.2.10rc1-3 13 10210 12.so.0.10[.0]
120 * 1.2.10 13 10210 12.so.0.10[.0]
121 * 1.2.11beta1-4 13 10211 12.so.0.11[.0]
122 * 1.0.19rc1-5 10 10019 10.so.0.19[.0]
123 * 1.2.11rc1-5 13 10211 12.so.0.11[.0]
124 * 1.0.19 10 10019 10.so.0.19[.0]
125 * 1.2.11 13 10211 12.so.0.11[.0]
126 * 1.0.20 10 10020 10.so.0.20[.0]
127 * 1.2.12 13 10212 12.so.0.12[.0]
128 * 1.2.13beta1 13 10213 12.so.0.13[.0]
129 * 1.0.21 10 10021 10.so.0.21[.0]
130 * 1.2.13 13 10213 12.so.0.13[.0]
131 * 1.2.14beta1-2 13 10214 12.so.0.14[.0]
132 * 1.0.22rc1 10 10022 10.so.0.22[.0]
133 * 1.2.14rc1 13 10214 12.so.0.14[.0]
134 * 1.0.22 10 10022 10.so.0.22[.0]
135 * 1.2.14 13 10214 12.so.0.14[.0]
136 * 1.2.15beta1-6 13 10215 12.so.0.15[.0]
137 * 1.0.23rc1-5 10 10023 10.so.0.23[.0]
138 * 1.2.15rc1-5 13 10215 12.so.0.15[.0]
139 * 1.0.23 10 10023 10.so.0.23[.0]
140 * 1.2.15 13 10215 12.so.0.15[.0]
141 * 1.2.16beta1-2 13 10216 12.so.0.16[.0]
142 * 1.2.16rc1 13 10216 12.so.0.16[.0]
143 * 1.0.24 10 10024 10.so.0.24[.0]
144 * 1.2.16 13 10216 12.so.0.16[.0]
145 * 1.2.17beta1-2 13 10217 12.so.0.17[.0]
146 * 1.0.25rc1 10 10025 10.so.0.25[.0]
147 * 1.2.17rc1-3 13 10217 12.so.0.17[.0]
148 * 1.0.25 10 10025 10.so.0.25[.0]
149 * 1.2.17 13 10217 12.so.0.17[.0]
150 * 1.0.26 10 10026 10.so.0.26[.0]
151 * 1.2.18 13 10218 12.so.0.18[.0]
152 * 1.2.19beta1-31 13 10219 12.so.0.19[.0]
153 * 1.0.27rc1-6 10 10027 10.so.0.27[.0]
154 * 1.2.19rc1-6 13 10219 12.so.0.19[.0]
155 * 1.0.27 10 10027 10.so.0.27[.0]
156 * 1.2.19 13 10219 12.so.0.19[.0]
157 * 1.2.20beta01-04 13 10220 12.so.0.20[.0]
158 * 1.0.28rc1-6 10 10028 10.so.0.28[.0]
159 * 1.2.20rc1-6 13 10220 12.so.0.20[.0]
160 * 1.0.28 10 10028 10.so.0.28[.0]
161 * 1.2.20 13 10220 12.so.0.20[.0]
162 * 1.2.21beta1-2 13 10221 12.so.0.21[.0]
163 * 1.2.21rc1-3 13 10221 12.so.0.21[.0]
164 * 1.0.29 10 10029 10.so.0.29[.0]
165 * 1.2.21 13 10221 12.so.0.21[.0]
166 * 1.2.22beta1-4 13 10222 12.so.0.22[.0]
167 * 1.0.30rc1 10 10030 10.so.0.30[.0]
168 * 1.2.22rc1 13 10222 12.so.0.22[.0]
169 * 1.0.30 10 10030 10.so.0.30[.0]
170 * 1.2.22 13 10222 12.so.0.22[.0]
171 * 1.2.23beta01-05 13 10223 12.so.0.23[.0]
172 * 1.2.23rc01 13 10223 12.so.0.23[.0]
173 * 1.2.23 13 10223 12.so.0.23[.0]
174 * 1.2.24beta01-02 13 10224 12.so.0.24[.0]
175 * 1.2.24rc01 13 10224 12.so.0.24[.0]
176 * 1.2.24 13 10224 12.so.0.24[.0]
177 * 1.2.25beta01-06 13 10225 12.so.0.25[.0]
178 * 1.2.25rc01-02 13 10225 12.so.0.25[.0]
179 * 1.0.31 10 10031 10.so.0.31[.0]
180 * 1.2.25 13 10225 12.so.0.25[.0]
181 * 1.2.26beta01-06 13 10226 12.so.0.26[.0]
182 * 1.2.26rc01 13 10226 12.so.0.26[.0]
183 * 1.2.26 13 10226 12.so.0.26[.0]
184 * 1.0.32 10 10032 10.so.0.32[.0]
185 * 1.2.27beta01-06 13 10227 12.so.0.27[.0]
186 * 1.2.27rc01 13 10227 12.so.0.27[.0]
187 * 1.0.33 10 10033 10.so.0.33[.0]
188 * 1.2.27 13 10227 12.so.0.27[.0]
189 * 1.0.34 10 10034 10.so.0.34[.0]
190 * 1.2.28 13 10228 12.so.0.28[.0]
191 * 1.2.29beta01-03 13 10229 12.so.0.29[.0]
192 * 1.2.29rc01 13 10229 12.so.0.29[.0]
193 * 1.0.35 10 10035 10.so.0.35[.0]
194 * 1.2.29 13 10229 12.so.0.29[.0]
195 *
196 * Henceforth the source version will match the shared-library major
197 * and minor numbers; the shared-library major version number will be
198 * used for changes in backward compatibility, as it is intended. The
199 * PNG_LIBPNG_VER macro, which is not used within libpng but is available
200 * for applications, is an unsigned integer of the form xyyzz corresponding
201 * to the source version x.y.z (leading zeros in y and z). Beta versions
202 * were given the previous public release number plus a letter, until
203 * version 1.0.6j; from then on they were given the upcoming public
204 * release number plus "betaNN" or "rcNN".
205 *
206 * Binary incompatibility exists only when applications make direct access
207 * to the info_ptr or png_ptr members through png.h, and the compiled
208 * application is loaded with a different version of the library.
209 *
210 * DLLNUM will change each time there are forward or backward changes
211 * in binary compatibility (e.g., when a new feature is added).
212 *
213 * See libpng.txt or libpng.3 for more information. The PNG specification
214 * is available as a W3C Recommendation and as an ISO Specification,
215 * <http://www.w3.org/TR/2003/REC-PNG-20031110/
216 */
217
218 /*
219 * COPYRIGHT NOTICE, DISCLAIMER, and LICENSE:
220 *
221 * If you modify libpng you may insert additional notices immediately following
222 * this sentence.
223 *
224 * libpng versions 1.2.6, August 15, 2004, through 1.2.29, May 8, 2008, are
225 * Copyright (c) 2004, 2006-2008 Glenn Randers-Pehrson, and are
226 * distributed according to the same disclaimer and license as libpng-1.2.5
227 * with the following individual added to the list of Contributing Authors:
228 *
229 * Cosmin Truta
230 *
231 * libpng versions 1.0.7, July 1, 2000, through 1.2.5, October 3, 2002, are
232 * Copyright (c) 2000-2002 Glenn Randers-Pehrson, and are
233 * distributed according to the same disclaimer and license as libpng-1.0.6
234 * with the following individuals added to the list of Contributing Authors:
235 *
236 * Simon-Pierre Cadieux
237 * Eric S. Raymond
238 * Gilles Vollant
239 *
240 * and with the following additions to the disclaimer:
241 *
242 * There is no warranty against interference with your enjoyment of the
243 * library or against infringement. There is no warranty that our
244 * efforts or the library will fulfill any of your particular purposes
245 * or needs. This library is provided with all faults, and the entire
246 * risk of satisfactory quality, performance, accuracy, and effort is with
247 * the user.
248 *
249 * libpng versions 0.97, January 1998, through 1.0.6, March 20, 2000, are
250 * Copyright (c) 1998, 1999, 2000 Glenn Randers-Pehrson, and are
251 * distributed according to the same disclaimer and license as libpng-0.96,
252 * with the following individuals added to the list of Contributing Authors:
253 *
254 * Tom Lane
255 * Glenn Randers-Pehrson
256 * Willem van Schaik
257 *
258 * libpng versions 0.89, June 1996, through 0.96, May 1997, are
259 * Copyright (c) 1996, 1997 Andreas Dilger
260 * Distributed according to the same disclaimer and license as libpng-0.88,
261 * with the following individuals added to the list of Contributing Authors:
262 *
263 * John Bowler
264 * Kevin Bracey
265 * Sam Bushell
266 * Magnus Holmgren
267 * Greg Roelofs
268 * Tom Tanner
269 *
270 * libpng versions 0.5, May 1995, through 0.88, January 1996, are
271 * Copyright (c) 1995, 1996 Guy Eric Schalnat, Group 42, Inc.
272 *
273 * For the purposes of this copyright and license, "Contributing Authors"
274 * is defined as the following set of individuals:
275 *
276 * Andreas Dilger
277 * Dave Martindale
278 * Guy Eric Schalnat
279 * Paul Schmidt
280 * Tim Wegner
281 *
282 * The PNG Reference Library is supplied "AS IS". The Contributing Authors
283 * and Group 42, Inc. disclaim all warranties, expressed or implied,
284 * including, without limitation, the warranties of merchantability and of
285 * fitness for any purpose. The Contributing Authors and Group 42, Inc.
286 * assume no liability for direct, indirect, incidental, special, exemplary,
287 * or consequential damages, which may result from the use of the PNG
288 * Reference Library, even if advised of the possibility of such damage.
289 *
290 * Permission is hereby granted to use, copy, modify, and distribute this
291 * source code, or portions hereof, for any purpose, without fee, subject
292 * to the following restrictions:
293 *
294 * 1. The origin of this source code must not be misrepresented.
295 *
296 * 2. Altered versions must be plainly marked as such and
297 * must not be misrepresented as being the original source.
298 *
299 * 3. This Copyright notice may not be removed or altered from
300 * any source or altered source distribution.
301 *
302 * The Contributing Authors and Group 42, Inc. specifically permit, without
303 * fee, and encourage the use of this source code as a component to
304 * supporting the PNG file format in commercial products. If you use this
305 * source code in a product, acknowledgment is not required but would be
306 * appreciated.
307 */
308
309 /*
310 * A "png_get_copyright" function is available, for convenient use in "about"
311 * boxes and the like:
312 *
313 * printf("%s",png_get_copyright(NULL));
314 *
315 * Also, the PNG logo (in PNG format, of course) is supplied in the
316 * files "pngbar.png" and "pngbar.jpg (88x31) and "pngnow.png" (98x31).
317 */
318
319 /*
320 * Libpng is OSI Certified Open Source Software. OSI Certified is a
321 * certification mark of the Open Source Initiative.
322 */
323
324 /*
325 * The contributing authors would like to thank all those who helped
326 * with testing, bug fixes, and patience. This wouldn't have been
327 * possible without all of you.
328 *
329 * Thanks to Frank J. T. Wojcik for helping with the documentation.
330 */
331
332 /*
333 * Y2K compliance in libpng:
334 * =========================
335 *
336 * May 8, 2008
337 *
338 * Since the PNG Development group is an ad-hoc body, we can't make
339 * an official declaration.
340 *
341 * This is your unofficial assurance that libpng from version 0.71 and
342 * upward through 1.2.29 are Y2K compliant. It is my belief that earlier
343 * versions were also Y2K compliant.
344 *
345 * Libpng only has three year fields. One is a 2-byte unsigned integer
346 * that will hold years up to 65535. The other two hold the date in text
347 * format, and will hold years up to 9999.
348 *
349 * The integer is
350 * "png_uint_16 year" in png_time_struct.
351 *
352 * The strings are
353 * "png_charp time_buffer" in png_struct and
354 * "near_time_buffer", which is a local character string in png.c.
355 *
356 * There are seven time-related functions:
357 * png.c: png_convert_to_rfc_1123() in png.c
358 * (formerly png_convert_to_rfc_1152() in error)
359 * png_convert_from_struct_tm() in pngwrite.c, called in pngwrite.c
360 * png_convert_from_time_t() in pngwrite.c
361 * png_get_tIME() in pngget.c
362 * png_handle_tIME() in pngrutil.c, called in pngread.c
363 * png_set_tIME() in pngset.c
364 * png_write_tIME() in pngwutil.c, called in pngwrite.c
365 *
366 * All handle dates properly in a Y2K environment. The
367 * png_convert_from_time_t() function calls gmtime() to convert from system
368 * clock time, which returns (year - 1900), which we properly convert to
369 * the full 4-digit year. There is a possibility that applications using
370 * libpng are not passing 4-digit years into the png_convert_to_rfc_1123()
371 * function, or that they are incorrectly passing only a 2-digit year
372 * instead of "year - 1900" into the png_convert_from_struct_tm() function,
373 * but this is not under our control. The libpng documentation has always
374 * stated that it works with 4-digit years, and the APIs have been
375 * documented as such.
376 *
377 * The tIME chunk itself is also Y2K compliant. It uses a 2-byte unsigned
378 * integer to hold the year, and can hold years as large as 65535.
379 *
380 * zlib, upon which libpng depends, is also Y2K compliant. It contains
381 * no date-related code.
382 *
383 * Glenn Randers-Pehrson
384 * libpng maintainer
385 * PNG Development Group
386 */
387
388 #ifndef PNG_H
389 #define PNG_H
390
391 /* This is not the place to learn how to use libpng. The file libpng.txt
392 * describes how to use libpng, and the file example.c summarizes it
393 * with some code on which to build. This file is useful for looking
394 * at the actual function definitions and structure components.
395 */
396
397 /* Version information for png.h - this should match the version in png.c */
398 #define PNG_LIBPNG_VER_STRING "1.2.29"
399 #define PNG_HEADER_VERSION_STRING \
400 " libpng version 1.2.29 - May 8, 2008\n"
401
402 #define PNG_LIBPNG_VER_SONUM 0
403 #define PNG_LIBPNG_VER_DLLNUM 13
404
405 /* These should match the first 3 components of PNG_LIBPNG_VER_STRING: */
406 #define PNG_LIBPNG_VER_MAJOR 1
407 #define PNG_LIBPNG_VER_MINOR 2
408 #define PNG_LIBPNG_VER_RELEASE 29
409 /* This should match the numeric part of the final component of
410 * PNG_LIBPNG_VER_STRING, omitting any leading zero: */
411
412 #define PNG_LIBPNG_VER_BUILD 0
413
414 /* Release Status */
415 #define PNG_LIBPNG_BUILD_ALPHA 1
416 #define PNG_LIBPNG_BUILD_BETA 2
417 #define PNG_LIBPNG_BUILD_RC 3
418 #define PNG_LIBPNG_BUILD_STABLE 4
419 #define PNG_LIBPNG_BUILD_RELEASE_STATUS_MASK 7
420
421 /* Release-Specific Flags */
422 #define PNG_LIBPNG_BUILD_PATCH 8 /* Can be OR'ed with
423 PNG_LIBPNG_BUILD_STABLE only */
424 #define PNG_LIBPNG_BUILD_PRIVATE 16 /* Cannot be OR'ed with
425 PNG_LIBPNG_BUILD_SPECIAL */
426 #define PNG_LIBPNG_BUILD_SPECIAL 32 /* Cannot be OR'ed with
427 PNG_LIBPNG_BUILD_PRIVATE */
428
429 #define PNG_LIBPNG_BUILD_BASE_TYPE PNG_LIBPNG_BUILD_STABLE
430
431 /* Careful here. At one time, Guy wanted to use 082, but that would be octal.
432 * We must not include leading zeros.
433 * Versions 0.7 through 1.0.0 were in the range 0 to 100 here (only
434 * version 1.0.0 was mis-numbered 100 instead of 10000). From
435 * version 1.0.1 it's xxyyzz, where x=major, y=minor, z=release */
436 #define PNG_LIBPNG_VER 10229 /* 1.2.29 */
437
438 #ifndef PNG_VERSION_INFO_ONLY
439 /* include the compression library's header */
440 #include "zlib.h"
441 #endif
442
443 /* include all user configurable info, including optional assembler routines */
444 #include "pngconf.h"
445
446 /*
447 * Added at libpng-1.2.8 */
448 /* Ref MSDN: Private as priority over Special
449 * VS_FF_PRIVATEBUILD File *was not* built using standard release
450 * procedures. If this value is given, the StringFileInfo block must
451 * contain a PrivateBuild string.
452 *
453 * VS_FF_SPECIALBUILD File *was* built by the original company using
454 * standard release procedures but is a variation of the standard
455 * file of the same version number. If this value is given, the
456 * StringFileInfo block must contain a SpecialBuild string.
457 */
458
459 #if defined(PNG_USER_PRIVATEBUILD)
460 # define PNG_LIBPNG_BUILD_TYPE \
461 (PNG_LIBPNG_BUILD_BASE_TYPE | PNG_LIBPNG_BUILD_PRIVATE)
462 #else
463 # if defined(PNG_LIBPNG_SPECIALBUILD)
464 # define PNG_LIBPNG_BUILD_TYPE \
465 (PNG_LIBPNG_BUILD_BASE_TYPE | PNG_LIBPNG_BUILD_SPECIAL)
466 # else
467 # define PNG_LIBPNG_BUILD_TYPE (PNG_LIBPNG_BUILD_BASE_TYPE)
468 # endif
469 #endif
470
471 #ifndef PNG_VERSION_INFO_ONLY
472
473 /* Inhibit C++ name-mangling for libpng functions but not for system calls. */
474 #ifdef __cplusplus
475 extern "C" {
476 #endif /* __cplusplus */
477
478 /* This file is arranged in several sections. The first section contains
479 * structure and type definitions. The second section contains the external
480 * library functions, while the third has the internal library functions,
481 * which applications aren't expected to use directly.
482 */
483
484 #ifndef PNG_NO_TYPECAST_NULL
485 #define int_p_NULL (int *)NULL
486 #define png_bytep_NULL (png_bytep)NULL
487 #define png_bytepp_NULL (png_bytepp)NULL
488 #define png_doublep_NULL (png_doublep)NULL
489 #define png_error_ptr_NULL (png_error_ptr)NULL
490 #define png_flush_ptr_NULL (png_flush_ptr)NULL
491 #define png_free_ptr_NULL (png_free_ptr)NULL
492 #define png_infopp_NULL (png_infopp)NULL
493 #define png_malloc_ptr_NULL (png_malloc_ptr)NULL
494 #define png_read_status_ptr_NULL (png_read_status_ptr)NULL
495 #define png_rw_ptr_NULL (png_rw_ptr)NULL
496 #define png_structp_NULL (png_structp)NULL
497 #define png_uint_16p_NULL (png_uint_16p)NULL
498 #define png_voidp_NULL (png_voidp)NULL
499 #define png_write_status_ptr_NULL (png_write_status_ptr)NULL
500 #else
501 #define int_p_NULL NULL
502 #define png_bytep_NULL NULL
503 #define png_bytepp_NULL NULL
504 #define png_doublep_NULL NULL
505 #define png_error_ptr_NULL NULL
506 #define png_flush_ptr_NULL NULL
507 #define png_free_ptr_NULL NULL
508 #define png_infopp_NULL NULL
509 #define png_malloc_ptr_NULL NULL
510 #define png_read_status_ptr_NULL NULL
511 #define png_rw_ptr_NULL NULL
512 #define png_structp_NULL NULL
513 #define png_uint_16p_NULL NULL
514 #define png_voidp_NULL NULL
515 #define png_write_status_ptr_NULL NULL
516 #endif
517
518 /* variables declared in png.c - only it needs to define PNG_NO_EXTERN */
519 #if !defined(PNG_NO_EXTERN) || defined(PNG_ALWAYS_EXTERN)
520 /* Version information for C files, stored in png.c. This had better match
521 * the version above.
522 */
523 #ifdef PNG_USE_GLOBAL_ARRAYS
524 PNG_EXPORT_VAR (PNG_CONST char) png_libpng_ver[18];
525 /* need room for 99.99.99beta99z */
526 #else
527 #define png_libpng_ver png_get_header_ver(NULL)
528 #endif
529
530 #ifdef PNG_USE_GLOBAL_ARRAYS
531 /* This was removed in version 1.0.5c */
532 /* Structures to facilitate easy interlacing. See png.c for more details */
533 PNG_EXPORT_VAR (PNG_CONST int FARDATA) png_pass_start[7];
534 PNG_EXPORT_VAR (PNG_CONST int FARDATA) png_pass_inc[7];
535 PNG_EXPORT_VAR (PNG_CONST int FARDATA) png_pass_ystart[7];
536 PNG_EXPORT_VAR (PNG_CONST int FARDATA) png_pass_yinc[7];
537 PNG_EXPORT_VAR (PNG_CONST int FARDATA) png_pass_mask[7];
538 PNG_EXPORT_VAR (PNG_CONST int FARDATA) png_pass_dsp_mask[7];
539 /* This isn't currently used. If you need it, see png.c for more details.
540 PNG_EXPORT_VAR (PNG_CONST int FARDATA) png_pass_height[7];
541 */
542 #endif
543
544 #endif /* PNG_NO_EXTERN */
545
546 /* Three color definitions. The order of the red, green, and blue, (and the
547 * exact size) is not important, although the size of the fields need to
548 * be png_byte or png_uint_16 (as defined below).
549 */
550 typedef struct png_color_struct
551 {
552 png_byte red;
553 png_byte green;
554 png_byte blue;
555 } png_color;
556 typedef png_color FAR * png_colorp;
557 typedef png_color FAR * FAR * png_colorpp;
558
559 typedef struct png_color_16_struct
560 {
561 png_byte index; /* used for palette files */
562 png_uint_16 red; /* for use in red green blue files */
563 png_uint_16 green;
564 png_uint_16 blue;
565 png_uint_16 gray; /* for use in grayscale files */
566 } png_color_16;
567 typedef png_color_16 FAR * png_color_16p;
568 typedef png_color_16 FAR * FAR * png_color_16pp;
569
570 typedef struct png_color_8_struct
571 {
572 png_byte red; /* for use in red green blue files */
573 png_byte green;
574 png_byte blue;
575 png_byte gray; /* for use in grayscale files */
576 png_byte alpha; /* for alpha channel files */
577 } png_color_8;
578 typedef png_color_8 FAR * png_color_8p;
579 typedef png_color_8 FAR * FAR * png_color_8pp;
580
581 /*
582 * The following two structures are used for the in-core representation
583 * of sPLT chunks.
584 */
585 typedef struct png_sPLT_entry_struct
586 {
587 png_uint_16 red;
588 png_uint_16 green;
589 png_uint_16 blue;
590 png_uint_16 alpha;
591 png_uint_16 frequency;
592 } png_sPLT_entry;
593 typedef png_sPLT_entry FAR * png_sPLT_entryp;
594 typedef png_sPLT_entry FAR * FAR * png_sPLT_entrypp;
595
596 /* When the depth of the sPLT palette is 8 bits, the color and alpha samples
597 * occupy the LSB of their respective members, and the MSB of each member
598 * is zero-filled. The frequency member always occupies the full 16 bits.
599 */
600
601 typedef struct png_sPLT_struct
602 {
603 png_charp name; /* palette name */
604 png_byte depth; /* depth of palette samples */
605 png_sPLT_entryp entries; /* palette entries */
606 png_int_32 nentries; /* number of palette entries */
607 } png_sPLT_t;
608 typedef png_sPLT_t FAR * png_sPLT_tp;
609 typedef png_sPLT_t FAR * FAR * png_sPLT_tpp;
610
611 #ifdef PNG_TEXT_SUPPORTED
612 /* png_text holds the contents of a text/ztxt/itxt chunk in a PNG file,
613 * and whether that contents is compressed or not. The "key" field
614 * points to a regular zero-terminated C string. The "text", "lang", and
615 * "lang_key" fields can be regular C strings, empty strings, or NULL pointers.
616 * However, the * structure returned by png_get_text() will always contain
617 * regular zero-terminated C strings (possibly empty), never NULL pointers,
618 * so they can be safely used in printf() and other string-handling functions.
619 */
620 typedef struct png_text_struct
621 {
622 int compression; /* compression value:
623 -1: tEXt, none
624 0: zTXt, deflate
625 1: iTXt, none
626 2: iTXt, deflate */
627 png_charp key; /* keyword, 1-79 character description of "text" */
628 png_charp text; /* comment, may be an empty string (ie "")
629 or a NULL pointer */
630 png_size_t text_length; /* length of the text string */
631 #ifdef PNG_iTXt_SUPPORTED
632 png_size_t itxt_length; /* length of the itxt string */
633 png_charp lang; /* language code, 0-79 characters
634 or a NULL pointer */
635 png_charp lang_key; /* keyword translated UTF-8 string, 0 or more
636 chars or a NULL pointer */
637 #endif
638 } png_text;
639 typedef png_text FAR * png_textp;
640 typedef png_text FAR * FAR * png_textpp;
641 #endif
642
643 /* Supported compression types for text in PNG files (tEXt, and zTXt).
644 * The values of the PNG_TEXT_COMPRESSION_ defines should NOT be changed. */
645 #define PNG_TEXT_COMPRESSION_NONE_WR -3
646 #define PNG_TEXT_COMPRESSION_zTXt_WR -2
647 #define PNG_TEXT_COMPRESSION_NONE -1
648 #define PNG_TEXT_COMPRESSION_zTXt 0
649 #define PNG_ITXT_COMPRESSION_NONE 1
650 #define PNG_ITXT_COMPRESSION_zTXt 2
651 #define PNG_TEXT_COMPRESSION_LAST 3 /* Not a valid value */
652
653 /* png_time is a way to hold the time in an machine independent way.
654 * Two conversions are provided, both from time_t and struct tm. There
655 * is no portable way to convert to either of these structures, as far
656 * as I know. If you know of a portable way, send it to me. As a side
657 * note - PNG has always been Year 2000 compliant!
658 */
659 typedef struct png_time_struct
660 {
661 png_uint_16 year; /* full year, as in, 1995 */
662 png_byte month; /* month of year, 1 - 12 */
663 png_byte day; /* day of month, 1 - 31 */
664 png_byte hour; /* hour of day, 0 - 23 */
665 png_byte minute; /* minute of hour, 0 - 59 */
666 png_byte second; /* second of minute, 0 - 60 (for leap seconds) */
667 } png_time;
668 typedef png_time FAR * png_timep;
669 typedef png_time FAR * FAR * png_timepp;
670
671 #if defined(PNG_UNKNOWN_CHUNKS_SUPPORTED)
672 /* png_unknown_chunk is a structure to hold queued chunks for which there is
673 * no specific support. The idea is that we can use this to queue
674 * up private chunks for output even though the library doesn't actually
675 * know about their semantics.
676 */
677 #define PNG_CHUNK_NAME_LENGTH 5
678 typedef struct png_unknown_chunk_t
679 {
680 png_byte name[PNG_CHUNK_NAME_LENGTH];
681 png_byte *data;
682 png_size_t size;
683
684 /* libpng-using applications should NOT directly modify this byte. */
685 png_byte location; /* mode of operation at read time */
686 }
687 png_unknown_chunk;
688 typedef png_unknown_chunk FAR * png_unknown_chunkp;
689 typedef png_unknown_chunk FAR * FAR * png_unknown_chunkpp;
690 #endif
691
692 /* png_info is a structure that holds the information in a PNG file so
693 * that the application can find out the characteristics of the image.
694 * If you are reading the file, this structure will tell you what is
695 * in the PNG file. If you are writing the file, fill in the information
696 * you want to put into the PNG file, then call png_write_info().
697 * The names chosen should be very close to the PNG specification, so
698 * consult that document for information about the meaning of each field.
699 *
700 * With libpng < 0.95, it was only possible to directly set and read the
701 * the values in the png_info_struct, which meant that the contents and
702 * order of the values had to remain fixed. With libpng 0.95 and later,
703 * however, there are now functions that abstract the contents of
704 * png_info_struct from the application, so this makes it easier to use
705 * libpng with dynamic libraries, and even makes it possible to use
706 * libraries that don't have all of the libpng ancillary chunk-handing
707 * functionality.
708 *
709 * In any case, the order of the parameters in png_info_struct should NOT
710 * be changed for as long as possible to keep compatibility with applications
711 * that use the old direct-access method with png_info_struct.
712 *
713 * The following members may have allocated storage attached that should be
714 * cleaned up before the structure is discarded: palette, trans, text,
715 * pcal_purpose, pcal_units, pcal_params, hist, iccp_name, iccp_profile,
716 * splt_palettes, scal_unit, row_pointers, and unknowns. By default, these
717 * are automatically freed when the info structure is deallocated, if they were
718 * allocated internally by libpng. This behavior can be changed by means
719 * of the png_data_freer() function.
720 *
721 * More allocation details: all the chunk-reading functions that
722 * change these members go through the corresponding png_set_*
723 * functions. A function to clear these members is available: see
724 * png_free_data(). The png_set_* functions do not depend on being
725 * able to point info structure members to any of the storage they are
726 * passed (they make their own copies), EXCEPT that the png_set_text
727 * functions use the same storage passed to them in the text_ptr or
728 * itxt_ptr structure argument, and the png_set_rows and png_set_unknowns
729 * functions do not make their own copies.
730 */
731 typedef struct png_info_struct
732 {
733 /* the following are necessary for every PNG file */
734 png_uint_32 width; /* width of image in pixels (from IHDR) */
735 png_uint_32 height; /* height of image in pixels (from IHDR) */
736 png_uint_32 valid; /* valid chunk data (see PNG_INFO_ below) */
737 png_uint_32 rowbytes; /* bytes needed to hold an untransformed row */
738 png_colorp palette; /* array of color values (valid & PNG_INFO_PLTE) */
739 png_uint_16 num_palette; /* number of color entries in "palette" (PLTE) */
740 png_uint_16 num_trans; /* number of transparent palette color (tRNS) */
741 png_byte bit_depth; /* 1, 2, 4, 8, or 16 bits/channel (from IHDR) */
742 png_byte color_type; /* see PNG_COLOR_TYPE_ below (from IHDR) */
743 /* The following three should have been named *_method not *_type */
744 png_byte compression_type; /* must be PNG_COMPRESSION_TYPE_BASE (IHDR) */
745 png_byte filter_type; /* must be PNG_FILTER_TYPE_BASE (from IHDR) */
746 png_byte interlace_type; /* One of PNG_INTERLACE_NONE, PNG_INTERLACE_ADAM7 */
747
748 /* The following is informational only on read, and not used on writes. */
749 png_byte channels; /* number of data channels per pixel (1, 2, 3, 4) */
750 png_byte pixel_depth; /* number of bits per pixel */
751 png_byte spare_byte; /* to align the data, and for future use */
752 png_byte signature[8]; /* magic bytes read by libpng from start of file */
753
754 /* The rest of the data is optional. If you are reading, check the
755 * valid field to see if the information in these are valid. If you
756 * are writing, set the valid field to those chunks you want written,
757 * and initialize the appropriate fields below.
758 */
759
760 #if defined(PNG_gAMA_SUPPORTED) && defined(PNG_FLOATING_POINT_SUPPORTED)
761 /* The gAMA chunk describes the gamma characteristics of the system
762 * on which the image was created, normally in the range [1.0, 2.5].
763 * Data is valid if (valid & PNG_INFO_gAMA) is non-zero.
764 */
765 float gamma; /* gamma value of image, if (valid & PNG_INFO_gAMA) */
766 #endif
767
768 #if defined(PNG_sRGB_SUPPORTED)
769 /* GR-P, 0.96a */
770 /* Data valid if (valid & PNG_INFO_sRGB) non-zero. */
771 png_byte srgb_intent; /* sRGB rendering intent [0, 1, 2, or 3] */
772 #endif
773
774 #if defined(PNG_TEXT_SUPPORTED)
775 /* The tEXt, and zTXt chunks contain human-readable textual data in
776 * uncompressed, compressed, and optionally compressed forms, respectively.
777 * The data in "text" is an array of pointers to uncompressed,
778 * null-terminated C strings. Each chunk has a keyword that describes the
779 * textual data contained in that chunk. Keywords are not required to be
780 * unique, and the text string may be empty. Any number of text chunks may
781 * be in an image.
782 */
783 int num_text; /* number of comments read/to write */
784 int max_text; /* current size of text array */
785 png_textp text; /* array of comments read/to write */
786 #endif /* PNG_TEXT_SUPPORTED */
787
788 #if defined(PNG_tIME_SUPPORTED)
789 /* The tIME chunk holds the last time the displayed image data was
790 * modified. See the png_time struct for the contents of this struct.
791 */
792 png_time mod_time;
793 #endif
794
795 #if defined(PNG_sBIT_SUPPORTED)
796 /* The sBIT chunk specifies the number of significant high-order bits
797 * in the pixel data. Values are in the range [1, bit_depth], and are
798 * only specified for the channels in the pixel data. The contents of
799 * the low-order bits is not specified. Data is valid if
800 * (valid & PNG_INFO_sBIT) is non-zero.
801 */
802 png_color_8 sig_bit; /* significant bits in color channels */
803 #endif
804
805 #if defined(PNG_tRNS_SUPPORTED) || defined(PNG_READ_EXPAND_SUPPORTED) || \
806 defined(PNG_READ_BACKGROUND_SUPPORTED)
807 /* The tRNS chunk supplies transparency data for paletted images and
808 * other image types that don't need a full alpha channel. There are
809 * "num_trans" transparency values for a paletted image, stored in the
810 * same order as the palette colors, starting from index 0. Values
811 * for the data are in the range [0, 255], ranging from fully transparent
812 * to fully opaque, respectively. For non-paletted images, there is a
813 * single color specified that should be treated as fully transparent.
814 * Data is valid if (valid & PNG_INFO_tRNS) is non-zero.
815 */
816 png_bytep trans; /* transparent values for paletted image */
817 png_color_16 trans_values; /* transparent color for non-palette image */
818 #endif
819
820 #if defined(PNG_bKGD_SUPPORTED) || defined(PNG_READ_BACKGROUND_SUPPORTED)
821 /* The bKGD chunk gives the suggested image background color if the
822 * display program does not have its own background color and the image
823 * is needs to composited onto a background before display. The colors
824 * in "background" are normally in the same color space/depth as the
825 * pixel data. Data is valid if (valid & PNG_INFO_bKGD) is non-zero.
826 */
827 png_color_16 background;
828 #endif
829
830 #if defined(PNG_oFFs_SUPPORTED)
831 /* The oFFs chunk gives the offset in "offset_unit_type" units rightwards
832 * and downwards from the top-left corner of the display, page, or other
833 * application-specific co-ordinate space. See the PNG_OFFSET_ defines
834 * below for the unit types. Valid if (valid & PNG_INFO_oFFs) non-zero.
835 */
836 png_int_32 x_offset; /* x offset on page */
837 png_int_32 y_offset; /* y offset on page */
838 png_byte offset_unit_type; /* offset units type */
839 #endif
840
841 #if defined(PNG_pHYs_SUPPORTED)
842 /* The pHYs chunk gives the physical pixel density of the image for
843 * display or printing in "phys_unit_type" units (see PNG_RESOLUTION_
844 * defines below). Data is valid if (valid & PNG_INFO_pHYs) is non-zero.
845 */
846 png_uint_32 x_pixels_per_unit; /* horizontal pixel density */
847 png_uint_32 y_pixels_per_unit; /* vertical pixel density */
848 png_byte phys_unit_type; /* resolution type (see PNG_RESOLUTION_ below) */
849 #endif
850
851 #if defined(PNG_hIST_SUPPORTED)
852 /* The hIST chunk contains the relative frequency or importance of the
853 * various palette entries, so that a viewer can intelligently select a
854 * reduced-color palette, if required. Data is an array of "num_palette"
855 * values in the range [0,65535]. Data valid if (valid & PNG_INFO_hIST)
856 * is non-zero.
857 */
858 png_uint_16p hist;
859 #endif
860
861 #ifdef PNG_cHRM_SUPPORTED
862 /* The cHRM chunk describes the CIE color characteristics of the monitor
863 * on which the PNG was created. This data allows the viewer to do gamut
864 * mapping of the input image to ensure that the viewer sees the same
865 * colors in the image as the creator. Values are in the range
866 * [0.0, 0.8]. Data valid if (valid & PNG_INFO_cHRM) non-zero.
867 */
868 #ifdef PNG_FLOATING_POINT_SUPPORTED
869 float x_white;
870 float y_white;
871 float x_red;
872 float y_red;
873 float x_green;
874 float y_green;
875 float x_blue;
876 float y_blue;
877 #endif
878 #endif
879
880 #if defined(PNG_pCAL_SUPPORTED)
881 /* The pCAL chunk describes a transformation between the stored pixel
882 * values and original physical data values used to create the image.
883 * The integer range [0, 2^bit_depth - 1] maps to the floating-point
884 * range given by [pcal_X0, pcal_X1], and are further transformed by a
885 * (possibly non-linear) transformation function given by "pcal_type"
886 * and "pcal_params" into "pcal_units". Please see the PNG_EQUATION_
887 * defines below, and the PNG-Group's PNG extensions document for a
888 * complete description of the transformations and how they should be
889 * implemented, and for a description of the ASCII parameter strings.
890 * Data values are valid if (valid & PNG_INFO_pCAL) non-zero.
891 */
892 png_charp pcal_purpose; /* pCAL chunk description string */
893 png_int_32 pcal_X0; /* minimum value */
894 png_int_32 pcal_X1; /* maximum value */
895 png_charp pcal_units; /* Latin-1 string giving physical units */
896 png_charpp pcal_params; /* ASCII strings containing parameter values */
897 png_byte pcal_type; /* equation type (see PNG_EQUATION_ below) */
898 png_byte pcal_nparams; /* number of parameters given in pcal_params */
899 #endif
900
901 /* New members added in libpng-1.0.6 */
902 #ifdef PNG_FREE_ME_SUPPORTED
903 png_uint_32 free_me; /* flags items libpng is responsible for freeing */
904 #endif
905
906 #if defined(PNG_UNKNOWN_CHUNKS_SUPPORTED)
907 /* storage for unknown chunks that the library doesn't recognize. */
908 png_unknown_chunkp unknown_chunks;
909 png_size_t unknown_chunks_num;
910 #endif
911
912 #if defined(PNG_iCCP_SUPPORTED)
913 /* iCCP chunk data. */
914 png_charp iccp_name; /* profile name */
915 png_charp iccp_profile; /* International Color Consortium profile data */
916 /* Note to maintainer: should be png_bytep */
917 png_uint_32 iccp_proflen; /* ICC profile data length */
918 png_byte iccp_compression; /* Always zero */
919 #endif
920
921 #if defined(PNG_sPLT_SUPPORTED)
922 /* data on sPLT chunks (there may be more than one). */
923 png_sPLT_tp splt_palettes;
924 png_uint_32 splt_palettes_num;
925 #endif
926
927 #if defined(PNG_sCAL_SUPPORTED)
928 /* The sCAL chunk describes the actual physical dimensions of the
929 * subject matter of the graphic. The chunk contains a unit specification
930 * a byte value, and two ASCII strings representing floating-point
931 * values. The values are width and height corresponsing to one pixel
932 * in the image. This external representation is converted to double
933 * here. Data values are valid if (valid & PNG_INFO_sCAL) is non-zero.
934 */
935 png_byte scal_unit; /* unit of physical scale */
936 #ifdef PNG_FLOATING_POINT_SUPPORTED
937 double scal_pixel_width; /* width of one pixel */
938 double scal_pixel_height; /* height of one pixel */
939 #endif
940 #ifdef PNG_FIXED_POINT_SUPPORTED
941 png_charp scal_s_width; /* string containing height */
942 png_charp scal_s_height; /* string containing width */
943 #endif
944 #endif
945
946 #if defined(PNG_INFO_IMAGE_SUPPORTED)
947 /* Memory has been allocated if (valid & PNG_ALLOCATED_INFO_ROWS) non-zero */
948 /* Data valid if (valid & PNG_INFO_IDAT) non-zero */
949 png_bytepp row_pointers; /* the image bits */
950 #endif
951
952 #if defined(PNG_FIXED_POINT_SUPPORTED) && defined(PNG_gAMA_SUPPORTED)
953 png_fixed_point int_gamma; /* gamma of image, if (valid & PNG_INFO_gAMA) */
954 #endif
955
956 #if defined(PNG_cHRM_SUPPORTED) && defined(PNG_FIXED_POINT_SUPPORTED)
957 png_fixed_point int_x_white;
958 png_fixed_point int_y_white;
959 png_fixed_point int_x_red;
960 png_fixed_point int_y_red;
961 png_fixed_point int_x_green;
962 png_fixed_point int_y_green;
963 png_fixed_point int_x_blue;
964 png_fixed_point int_y_blue;
965 #endif
966
967 } png_info;
968
969 typedef png_info FAR * png_infop;
970 typedef png_info FAR * FAR * png_infopp;
971
972 /* Maximum positive integer used in PNG is (2^31)-1 */
973 #define PNG_UINT_31_MAX ((png_uint_32)0x7fffffffL)
974 #define PNG_UINT_32_MAX ((png_uint_32)(-1))
975 #define PNG_SIZE_MAX ((png_size_t)(-1))
976 #if defined(PNG_1_0_X) || defined (PNG_1_2_X)
977 /* PNG_MAX_UINT is deprecated; use PNG_UINT_31_MAX instead. */
978 #define PNG_MAX_UINT PNG_UINT_31_MAX
979 #endif
980
981 /* These describe the color_type field in png_info. */
982 /* color type masks */
983 #define PNG_COLOR_MASK_PALETTE 1
984 #define PNG_COLOR_MASK_COLOR 2
985 #define PNG_COLOR_MASK_ALPHA 4
986
987 /* color types. Note that not all combinations are legal */
988 #define PNG_COLOR_TYPE_GRAY 0
989 #define PNG_COLOR_TYPE_PALETTE (PNG_COLOR_MASK_COLOR | PNG_COLOR_MASK_PALETTE)
990 #define PNG_COLOR_TYPE_RGB (PNG_COLOR_MASK_COLOR)
991 #define PNG_COLOR_TYPE_RGB_ALPHA (PNG_COLOR_MASK_COLOR | PNG_COLOR_MASK_ALPHA)
992 #define PNG_COLOR_TYPE_GRAY_ALPHA (PNG_COLOR_MASK_ALPHA)
993 /* aliases */
994 #define PNG_COLOR_TYPE_RGBA PNG_COLOR_TYPE_RGB_ALPHA
995 #define PNG_COLOR_TYPE_GA PNG_COLOR_TYPE_GRAY_ALPHA
996
997 /* This is for compression type. PNG 1.0-1.2 only define the single type. */
998 #define PNG_COMPRESSION_TYPE_BASE 0 /* Deflate method 8, 32K window */
999 #define PNG_COMPRESSION_TYPE_DEFAULT PNG_COMPRESSION_TYPE_BASE
1000
1001 /* This is for filter type. PNG 1.0-1.2 only define the single type. */
1002 #define PNG_FILTER_TYPE_BASE 0 /* Single row per-byte filtering */
1003 #define PNG_INTRAPIXEL_DIFFERENCING 64 /* Used only in MNG datastreams */
1004 #define PNG_FILTER_TYPE_DEFAULT PNG_FILTER_TYPE_BASE
1005
1006 /* These are for the interlacing type. These values should NOT be changed. */
1007 #define PNG_INTERLACE_NONE 0 /* Non-interlaced image */
1008 #define PNG_INTERLACE_ADAM7 1 /* Adam7 interlacing */
1009 #define PNG_INTERLACE_LAST 2 /* Not a valid value */
1010
1011 /* These are for the oFFs chunk. These values should NOT be changed. */
1012 #define PNG_OFFSET_PIXEL 0 /* Offset in pixels */
1013 #define PNG_OFFSET_MICROMETER 1 /* Offset in micrometers (1/10^6 meter) */
1014 #define PNG_OFFSET_LAST 2 /* Not a valid value */
1015
1016 /* These are for the pCAL chunk. These values should NOT be changed. */
1017 #define PNG_EQUATION_LINEAR 0 /* Linear transformation */
1018 #define PNG_EQUATION_BASE_E 1 /* Exponential base e transform */
1019 #define PNG_EQUATION_ARBITRARY 2 /* Arbitrary base exponential transform */
1020 #define PNG_EQUATION_HYPERBOLIC 3 /* Hyperbolic sine transformation */
1021 #define PNG_EQUATION_LAST 4 /* Not a valid value */
1022
1023 /* These are for the sCAL chunk. These values should NOT be changed. */
1024 #define PNG_SCALE_UNKNOWN 0 /* unknown unit (image scale) */
1025 #define PNG_SCALE_METER 1 /* meters per pixel */
1026 #define PNG_SCALE_RADIAN 2 /* radians per pixel */
1027 #define PNG_SCALE_LAST 3 /* Not a valid value */
1028
1029 /* These are for the pHYs chunk. These values should NOT be changed. */
1030 #define PNG_RESOLUTION_UNKNOWN 0 /* pixels/unknown unit (aspect ratio) */
1031 #define PNG_RESOLUTION_METER 1 /* pixels/meter */
1032 #define PNG_RESOLUTION_LAST 2 /* Not a valid value */
1033
1034 /* These are for the sRGB chunk. These values should NOT be changed. */
1035 #define PNG_sRGB_INTENT_PERCEPTUAL 0
1036 #define PNG_sRGB_INTENT_RELATIVE 1
1037 #define PNG_sRGB_INTENT_SATURATION 2
1038 #define PNG_sRGB_INTENT_ABSOLUTE 3
1039 #define PNG_sRGB_INTENT_LAST 4 /* Not a valid value */
1040
1041 /* This is for text chunks */
1042 #define PNG_KEYWORD_MAX_LENGTH 79
1043
1044 /* Maximum number of entries in PLTE/sPLT/tRNS arrays */
1045 #define PNG_MAX_PALETTE_LENGTH 256
1046
1047 /* These determine if an ancillary chunk's data has been successfully read
1048 * from the PNG header, or if the application has filled in the corresponding
1049 * data in the info_struct to be written into the output file. The values
1050 * of the PNG_INFO_<chunk> defines should NOT be changed.
1051 */
1052 #define PNG_INFO_gAMA 0x0001
1053 #define PNG_INFO_sBIT 0x0002
1054 #define PNG_INFO_cHRM 0x0004
1055 #define PNG_INFO_PLTE 0x0008
1056 #define PNG_INFO_tRNS 0x0010
1057 #define PNG_INFO_bKGD 0x0020
1058 #define PNG_INFO_hIST 0x0040
1059 #define PNG_INFO_pHYs 0x0080
1060 #define PNG_INFO_oFFs 0x0100
1061 #define PNG_INFO_tIME 0x0200
1062 #define PNG_INFO_pCAL 0x0400
1063 #define PNG_INFO_sRGB 0x0800 /* GR-P, 0.96a */
1064 #define PNG_INFO_iCCP 0x1000 /* ESR, 1.0.6 */
1065 #define PNG_INFO_sPLT 0x2000 /* ESR, 1.0.6 */
1066 #define PNG_INFO_sCAL 0x4000 /* ESR, 1.0.6 */
1067 #define PNG_INFO_IDAT 0x8000L /* ESR, 1.0.6 */
1068
1069 /* This is used for the transformation routines, as some of them
1070 * change these values for the row. It also should enable using
1071 * the routines for other purposes.
1072 */
1073 typedef struct png_row_info_struct
1074 {
1075 png_uint_32 width; /* width of row */
1076 png_uint_32 rowbytes; /* number of bytes in row */
1077 png_byte color_type; /* color type of row */
1078 png_byte bit_depth; /* bit depth of row */
1079 png_byte channels; /* number of channels (1, 2, 3, or 4) */
1080 png_byte pixel_depth; /* bits per pixel (depth * channels) */
1081 } png_row_info;
1082
1083 typedef png_row_info FAR * png_row_infop;
1084 typedef png_row_info FAR * FAR * png_row_infopp;
1085
1086 /* These are the function types for the I/O functions and for the functions
1087 * that allow the user to override the default I/O functions with his or her
1088 * own. The png_error_ptr type should match that of user-supplied warning
1089 * and error functions, while the png_rw_ptr type should match that of the
1090 * user read/write data functions.
1091 */
1092 typedef struct png_struct_def png_struct;
1093 typedef png_struct FAR * png_structp;
1094
1095 typedef void (PNGAPI *png_error_ptr) PNGARG((png_structp, png_const_charp));
1096 typedef void (PNGAPI *png_rw_ptr) PNGARG((png_structp, png_bytep, png_size_t));
1097 typedef void (PNGAPI *png_flush_ptr) PNGARG((png_structp));
1098 typedef void (PNGAPI *png_read_status_ptr) PNGARG((png_structp, png_uint_32,
1099 int));
1100 typedef void (PNGAPI *png_write_status_ptr) PNGARG((png_structp, png_uint_32,
1101 int));
1102
1103 #ifdef PNG_PROGRESSIVE_READ_SUPPORTED
1104 typedef void (PNGAPI *png_progressive_info_ptr) PNGARG((png_structp, png_infop));
1105 typedef void (PNGAPI *png_progressive_end_ptr) PNGARG((png_structp, png_infop));
1106 typedef void (PNGAPI *png_progressive_row_ptr) PNGARG((png_structp, png_bytep,
1107 png_uint_32, int));
1108 #endif
1109
1110 #if defined(PNG_READ_USER_TRANSFORM_SUPPORTED) || \
1111 defined(PNG_WRITE_USER_TRANSFORM_SUPPORTED) || \
1112 defined(PNG_LEGACY_SUPPORTED)
1113 typedef void (PNGAPI *png_user_transform_ptr) PNGARG((png_structp,
1114 png_row_infop, png_bytep));
1115 #endif
1116
1117 #if defined(PNG_USER_CHUNKS_SUPPORTED)
1118 typedef int (PNGAPI *png_user_chunk_ptr) PNGARG((png_structp, png_unknown_chunkp));
1119 #endif
1120 #if defined(PNG_UNKNOWN_CHUNKS_SUPPORTED)
1121 typedef void (PNGAPI *png_unknown_chunk_ptr) PNGARG((png_structp));
1122 #endif
1123
1124 /* Transform masks for the high-level interface */
1125 #define PNG_TRANSFORM_IDENTITY 0x0000 /* read and write */
1126 #define PNG_TRANSFORM_STRIP_16 0x0001 /* read only */
1127 #define PNG_TRANSFORM_STRIP_ALPHA 0x0002 /* read only */
1128 #define PNG_TRANSFORM_PACKING 0x0004 /* read and write */
1129 #define PNG_TRANSFORM_PACKSWAP 0x0008 /* read and write */
1130 #define PNG_TRANSFORM_EXPAND 0x0010 /* read only */
1131 #define PNG_TRANSFORM_INVERT_MONO 0x0020 /* read and write */
1132 #define PNG_TRANSFORM_SHIFT 0x0040 /* read and write */
1133 #define PNG_TRANSFORM_BGR 0x0080 /* read and write */
1134 #define PNG_TRANSFORM_SWAP_ALPHA 0x0100 /* read and write */
1135 #define PNG_TRANSFORM_SWAP_ENDIAN 0x0200 /* read and write */
1136 #define PNG_TRANSFORM_INVERT_ALPHA 0x0400 /* read and write */
1137 #define PNG_TRANSFORM_STRIP_FILLER 0x0800 /* WRITE only */
1138
1139 /* Flags for MNG supported features */
1140 #define PNG_FLAG_MNG_EMPTY_PLTE 0x01
1141 #define PNG_FLAG_MNG_FILTER_64 0x04
1142 #define PNG_ALL_MNG_FEATURES 0x05
1143
1144 typedef png_voidp (*png_malloc_ptr) PNGARG((png_structp, png_size_t));
1145 typedef void (*png_free_ptr) PNGARG((png_structp, png_voidp));
1146
1147 /* The structure that holds the information to read and write PNG files.
1148 * The only people who need to care about what is inside of this are the
1149 * people who will be modifying the library for their own special needs.
1150 * It should NOT be accessed directly by an application, except to store
1151 * the jmp_buf.
1152 */
1153
1154 struct png_struct_def
1155 {
1156 #ifdef PNG_SETJMP_SUPPORTED
1157 jmp_buf jmpbuf; /* used in png_error */
1158 #endif
1159 png_error_ptr error_fn; /* function for printing errors and aborting */
1160 png_error_ptr warning_fn; /* function for printing warnings */
1161 png_voidp error_ptr; /* user supplied struct for error functions */
1162 png_rw_ptr write_data_fn; /* function for writing output data */
1163 png_rw_ptr read_data_fn; /* function for reading input data */
1164 png_voidp io_ptr; /* ptr to application struct for I/O functions */
1165
1166 #if defined(PNG_READ_USER_TRANSFORM_SUPPORTED)
1167 png_user_transform_ptr read_user_transform_fn; /* user read transform */
1168 #endif
1169
1170 #if defined(PNG_WRITE_USER_TRANSFORM_SUPPORTED)
1171 png_user_transform_ptr write_user_transform_fn; /* user write transform */
1172 #endif
1173
1174 /* These were added in libpng-1.0.2 */
1175 #if defined(PNG_USER_TRANSFORM_PTR_SUPPORTED)
1176 #if defined(PNG_READ_USER_TRANSFORM_SUPPORTED) || \
1177 defined(PNG_WRITE_USER_TRANSFORM_SUPPORTED)
1178 png_voidp user_transform_ptr; /* user supplied struct for user transform */
1179 png_byte user_transform_depth; /* bit depth of user transformed pixels */
1180 png_byte user_transform_channels; /* channels in user transformed pixels */
1181 #endif
1182 #endif
1183
1184 png_uint_32 mode; /* tells us where we are in the PNG file */
1185 png_uint_32 flags; /* flags indicating various things to libpng */
1186 png_uint_32 transformations; /* which transformations to perform */
1187
1188 z_stream zstream; /* pointer to decompression structure (below) */
1189 png_bytep zbuf; /* buffer for zlib */
1190 png_size_t zbuf_size; /* size of zbuf */
1191 int zlib_level; /* holds zlib compression level */
1192 int zlib_method; /* holds zlib compression method */
1193 int zlib_window_bits; /* holds zlib compression window bits */
1194 int zlib_mem_level; /* holds zlib compression memory level */
1195 int zlib_strategy; /* holds zlib compression strategy */
1196
1197 png_uint_32 width; /* width of image in pixels */
1198 png_uint_32 height; /* height of image in pixels */
1199 png_uint_32 num_rows; /* number of rows in current pass */
1200 png_uint_32 usr_width; /* width of row at start of write */
1201 png_uint_32 rowbytes; /* size of row in bytes */
1202 png_uint_32 irowbytes; /* size of current interlaced row in bytes */
1203 png_uint_32 iwidth; /* width of current interlaced row in pixels */
1204 png_uint_32 row_number; /* current row in interlace pass */
1205 png_bytep prev_row; /* buffer to save previous (unfiltered) row */
1206 png_bytep row_buf; /* buffer to save current (unfiltered) row */
1207 #ifndef PNG_NO_WRITE_FILTERING
1208 png_bytep sub_row; /* buffer to save "sub" row when filtering */
1209 png_bytep up_row; /* buffer to save "up" row when filtering */
1210 png_bytep avg_row; /* buffer to save "avg" row when filtering */
1211 png_bytep paeth_row; /* buffer to save "Paeth" row when filtering */
1212 #endif
1213 png_row_info row_info; /* used for transformation routines */
1214
1215 png_uint_32 idat_size; /* current IDAT size for read */
1216 png_uint_32 crc; /* current chunk CRC value */
1217 png_colorp palette; /* palette from the input file */
1218 png_uint_16 num_palette; /* number of color entries in palette */
1219 png_uint_16 num_trans; /* number of transparency values */
1220 png_byte chunk_name[5]; /* null-terminated name of current chunk */
1221 png_byte compression; /* file compression type (always 0) */
1222 png_byte filter; /* file filter type (always 0) */
1223 png_byte interlaced; /* PNG_INTERLACE_NONE, PNG_INTERLACE_ADAM7 */
1224 png_byte pass; /* current interlace pass (0 - 6) */
1225 png_byte do_filter; /* row filter flags (see PNG_FILTER_ below ) */
1226 png_byte color_type; /* color type of file */
1227 png_byte bit_depth; /* bit depth of file */
1228 png_byte usr_bit_depth; /* bit depth of users row */
1229 png_byte pixel_depth; /* number of bits per pixel */
1230 png_byte channels; /* number of channels in file */
1231 png_byte usr_channels; /* channels at start of write */
1232 png_byte sig_bytes; /* magic bytes read/written from start of file */
1233
1234 #if defined(PNG_READ_FILLER_SUPPORTED) || defined(PNG_WRITE_FILLER_SUPPORTED)
1235 #ifdef PNG_LEGACY_SUPPORTED
1236 png_byte filler; /* filler byte for pixel expansion */
1237 #else
1238 png_uint_16 filler; /* filler bytes for pixel expansion */
1239 #endif
1240 #endif
1241
1242 #if defined(PNG_bKGD_SUPPORTED)
1243 png_byte background_gamma_type;
1244 # ifdef PNG_FLOATING_POINT_SUPPORTED
1245 float background_gamma;
1246 # endif
1247 png_color_16 background; /* background color in screen gamma space */
1248 #if defined(PNG_READ_GAMMA_SUPPORTED)
1249 png_color_16 background_1; /* background normalized to gamma 1.0 */
1250 #endif
1251 #endif /* PNG_bKGD_SUPPORTED */
1252
1253 #if defined(PNG_WRITE_FLUSH_SUPPORTED)
1254 png_flush_ptr output_flush_fn;/* Function for flushing output */
1255 png_uint_32 flush_dist; /* how many rows apart to flush, 0 - no flush */
1256 png_uint_32 flush_rows; /* number of rows written since last flush */
1257 #endif
1258
1259 #if defined(PNG_READ_GAMMA_SUPPORTED) || defined(PNG_READ_BACKGROUND_SUPPORTED)
1260 int gamma_shift; /* number of "insignificant" bits 16-bit gamma */
1261 #ifdef PNG_FLOATING_POINT_SUPPORTED
1262 float gamma; /* file gamma value */
1263 float screen_gamma; /* screen gamma value (display_exponent) */
1264 #endif
1265 #endif
1266
1267 #if defined(PNG_READ_GAMMA_SUPPORTED) || defined(PNG_READ_BACKGROUND_SUPPORTED)
1268 png_bytep gamma_table; /* gamma table for 8-bit depth files */
1269 png_bytep gamma_from_1; /* converts from 1.0 to screen */
1270 png_bytep gamma_to_1; /* converts from file to 1.0 */
1271 png_uint_16pp gamma_16_table; /* gamma table for 16-bit depth files */
1272 png_uint_16pp gamma_16_from_1; /* converts from 1.0 to screen */
1273 png_uint_16pp gamma_16_to_1; /* converts from file to 1.0 */
1274 #endif
1275
1276 #if defined(PNG_READ_GAMMA_SUPPORTED) || defined(PNG_sBIT_SUPPORTED)
1277 png_color_8 sig_bit; /* significant bits in each available channel */
1278 #endif
1279
1280 #if defined(PNG_READ_SHIFT_SUPPORTED) || defined(PNG_WRITE_SHIFT_SUPPORTED)
1281 png_color_8 shift; /* shift for significant bit tranformation */
1282 #endif
1283
1284 #if defined(PNG_tRNS_SUPPORTED) || defined(PNG_READ_BACKGROUND_SUPPORTED) \
1285 || defined(PNG_READ_EXPAND_SUPPORTED) || defined(PNG_READ_BACKGROUND_SUPPORTED)
1286 png_bytep trans; /* transparency values for paletted files */
1287 png_color_16 trans_values; /* transparency values for non-paletted files */
1288 #endif
1289
1290 png_read_status_ptr read_row_fn; /* called after each row is decoded */
1291 png_write_status_ptr write_row_fn; /* called after each row is encoded */
1292 #ifdef PNG_PROGRESSIVE_READ_SUPPORTED
1293 png_progressive_info_ptr info_fn; /* called after header data fully read */
1294 png_progressive_row_ptr row_fn; /* called after each prog. row is decoded */
1295 png_progressive_end_ptr end_fn; /* called after image is complete */
1296 png_bytep save_buffer_ptr; /* current location in save_buffer */
1297 png_bytep save_buffer; /* buffer for previously read data */
1298 png_bytep current_buffer_ptr; /* current location in current_buffer */
1299 png_bytep current_buffer; /* buffer for recently used data */
1300 png_uint_32 push_length; /* size of current input chunk */
1301 png_uint_32 skip_length; /* bytes to skip in input data */
1302 png_size_t save_buffer_size; /* amount of data now in save_buffer */
1303 png_size_t save_buffer_max; /* total size of save_buffer */
1304 png_size_t buffer_size; /* total amount of available input data */
1305 png_size_t current_buffer_size; /* amount of data now in current_buffer */
1306 int process_mode; /* what push library is currently doing */
1307 int cur_palette; /* current push library palette index */
1308
1309 # if defined(PNG_TEXT_SUPPORTED)
1310 png_size_t current_text_size; /* current size of text input data */
1311 png_size_t current_text_left; /* how much text left to read in input */
1312 png_charp current_text; /* current text chunk buffer */
1313 png_charp current_text_ptr; /* current location in current_text */
1314 # endif /* PNG_TEXT_SUPPORTED */
1315 #endif /* PNG_PROGRESSIVE_READ_SUPPORTED */
1316
1317 #if defined(__TURBOC__) && !defined(_Windows) && !defined(__FLAT__)
1318 /* for the Borland special 64K segment handler */
1319 png_bytepp offset_table_ptr;
1320 png_bytep offset_table;
1321 png_uint_16 offset_table_number;
1322 png_uint_16 offset_table_count;
1323 png_uint_16 offset_table_count_free;
1324 #endif
1325
1326 #if defined(PNG_READ_DITHER_SUPPORTED)
1327 png_bytep palette_lookup; /* lookup table for dithering */
1328 png_bytep dither_index; /* index translation for palette files */
1329 #endif
1330
1331 #if defined(PNG_READ_DITHER_SUPPORTED) || defined(PNG_hIST_SUPPORTED)
1332 png_uint_16p hist; /* histogram */
1333 #endif
1334
1335 #if defined(PNG_WRITE_WEIGHTED_FILTER_SUPPORTED)
1336 png_byte heuristic_method; /* heuristic for row filter selection */
1337 png_byte num_prev_filters; /* number of weights for previous rows */
1338 png_bytep prev_filters; /* filter type(s) of previous row(s) */
1339 png_uint_16p filter_weights; /* weight(s) for previous line(s) */
1340 png_uint_16p inv_filter_weights; /* 1/weight(s) for previous line(s) */
1341 png_uint_16p filter_costs; /* relative filter calculation cost */
1342 png_uint_16p inv_filter_costs; /* 1/relative filter calculation cost */
1343 #endif
1344
1345 #if defined(PNG_TIME_RFC1123_SUPPORTED)
1346 png_charp time_buffer; /* String to hold RFC 1123 time text */
1347 #endif
1348
1349 /* New members added in libpng-1.0.6 */
1350
1351 #ifdef PNG_FREE_ME_SUPPORTED
1352 png_uint_32 free_me; /* flags items libpng is responsible for freeing */
1353 #endif
1354
1355 #if defined(PNG_USER_CHUNKS_SUPPORTED)
1356 png_voidp user_chunk_ptr;
1357 png_user_chunk_ptr read_user_chunk_fn; /* user read chunk handler */
1358 #endif
1359
1360 #if defined(PNG_UNKNOWN_CHUNKS_SUPPORTED)
1361 int num_chunk_list;
1362 png_bytep chunk_list;
1363 #endif
1364
1365 /* New members added in libpng-1.0.3 */
1366 #if defined(PNG_READ_RGB_TO_GRAY_SUPPORTED)
1367 png_byte rgb_to_gray_status;
1368 /* These were changed from png_byte in libpng-1.0.6 */
1369 png_uint_16 rgb_to_gray_red_coeff;
1370 png_uint_16 rgb_to_gray_green_coeff;
1371 png_uint_16 rgb_to_gray_blue_coeff;
1372 #endif
1373
1374 /* New member added in libpng-1.0.4 (renamed in 1.0.9) */
1375 #if defined(PNG_MNG_FEATURES_SUPPORTED) || \
1376 defined(PNG_READ_EMPTY_PLTE_SUPPORTED) || \
1377 defined(PNG_WRITE_EMPTY_PLTE_SUPPORTED)
1378 /* changed from png_byte to png_uint_32 at version 1.2.0 */
1379 #ifdef PNG_1_0_X
1380 png_byte mng_features_permitted;
1381 #else
1382 png_uint_32 mng_features_permitted;
1383 #endif /* PNG_1_0_X */
1384 #endif
1385
1386 /* New member added in libpng-1.0.7 */
1387 #if defined(PNG_READ_GAMMA_SUPPORTED) || defined(PNG_READ_BACKGROUND_SUPPORTED)
1388 png_fixed_point int_gamma;
1389 #endif
1390
1391 /* New member added in libpng-1.0.9, ifdef'ed out in 1.0.12, enabled in 1.2.0 */
1392 #if defined(PNG_MNG_FEATURES_SUPPORTED)
1393 png_byte filter_type;
1394 #endif
1395
1396 #if defined(PNG_1_0_X)
1397 /* New member added in libpng-1.0.10, ifdef'ed out in 1.2.0 */
1398 png_uint_32 row_buf_size;
1399 #endif
1400
1401 /* New members added in libpng-1.2.0 */
1402 #if defined(PNG_ASSEMBLER_CODE_SUPPORTED)
1403 # if !defined(PNG_1_0_X)
1404 # if defined(PNG_MMX_CODE_SUPPORTED)
1405 png_byte mmx_bitdepth_threshold;
1406 png_uint_32 mmx_rowbytes_threshold;
1407 # endif
1408 png_uint_32 asm_flags;
1409 # endif
1410 #endif
1411
1412 /* New members added in libpng-1.0.2 but first enabled by default in 1.2.0 */
1413 #ifdef PNG_USER_MEM_SUPPORTED
1414 png_voidp mem_ptr; /* user supplied struct for mem functions */
1415 png_malloc_ptr malloc_fn; /* function for allocating memory */
1416 png_free_ptr free_fn; /* function for freeing memory */
1417 #endif
1418
1419 /* New member added in libpng-1.0.13 and 1.2.0 */
1420 png_bytep big_row_buf; /* buffer to save current (unfiltered) row */
1421
1422 #if defined(PNG_READ_DITHER_SUPPORTED)
1423 /* The following three members were added at version 1.0.14 and 1.2.4 */
1424 png_bytep dither_sort; /* working sort array */
1425 png_bytep index_to_palette; /* where the original index currently is */
1426 /* in the palette */
1427 png_bytep palette_to_index; /* which original index points to this */
1428 /* palette color */
1429 #endif
1430
1431 /* New members added in libpng-1.0.16 and 1.2.6 */
1432 png_byte compression_type;
1433
1434 #ifdef PNG_SET_USER_LIMITS_SUPPORTED
1435 png_uint_32 user_width_max;
1436 png_uint_32 user_height_max;
1437 #endif
1438
1439 /* New member added in libpng-1.0.25 and 1.2.17 */
1440 #if defined(PNG_UNKNOWN_CHUNKS_SUPPORTED)
1441 /* storage for unknown chunk that the library doesn't recognize. */
1442 png_unknown_chunk unknown_chunk;
1443 #endif
1444
1445 /* New members added in libpng-1.2.26 */
1446 png_uint_32 old_big_row_buf_size, old_prev_row_size;
1447 };
1448
1449
1450 /* This triggers a compiler error in png.c, if png.c and png.h
1451 * do not agree upon the version number.
1452 */
1453 typedef png_structp version_1_2_29;
1454
1455 typedef png_struct FAR * FAR * png_structpp;
1456
1457 /* Here are the function definitions most commonly used. This is not
1458 * the place to find out how to use libpng. See libpng.txt for the
1459 * full explanation, see example.c for the summary. This just provides
1460 * a simple one line description of the use of each function.
1461 */
1462
1463 /* Returns the version number of the library */
1464 extern PNG_EXPORT(png_uint_32,png_access_version_number) PNGARG((void));
1465
1466 /* Tell lib we have already handled the first <num_bytes> magic bytes.
1467 * Handling more than 8 bytes from the beginning of the file is an error.
1468 */
1469 extern PNG_EXPORT(void,png_set_sig_bytes) PNGARG((png_structp png_ptr,
1470 int num_bytes));
1471
1472 /* Check sig[start] through sig[start + num_to_check - 1] to see if it's a
1473 * PNG file. Returns zero if the supplied bytes match the 8-byte PNG
1474 * signature, and non-zero otherwise. Having num_to_check == 0 or
1475 * start > 7 will always fail (ie return non-zero).
1476 */
1477 extern PNG_EXPORT(int,png_sig_cmp) PNGARG((png_bytep sig, png_size_t start,
1478 png_size_t num_to_check));
1479
1480 /* Simple signature checking function. This is the same as calling
1481 * png_check_sig(sig, n) := !png_sig_cmp(sig, 0, n).
1482 */
1483 extern PNG_EXPORT(int,png_check_sig) PNGARG((png_bytep sig, int num));
1484
1485 /* Allocate and initialize png_ptr struct for reading, and any other memory. */
1486 extern PNG_EXPORT(png_structp,png_create_read_struct)
1487 PNGARG((png_const_charp user_png_ver, png_voidp error_ptr,
1488 png_error_ptr error_fn, png_error_ptr warn_fn));
1489
1490 /* Allocate and initialize png_ptr struct for writing, and any other memory */
1491 extern PNG_EXPORT(png_structp,png_create_write_struct)
1492 PNGARG((png_const_charp user_png_ver, png_voidp error_ptr,
1493 png_error_ptr error_fn, png_error_ptr warn_fn));
1494
1495 #ifdef PNG_WRITE_SUPPORTED
1496 extern PNG_EXPORT(png_uint_32,png_get_compression_buffer_size)
1497 PNGARG((png_structp png_ptr));
1498 #endif
1499
1500 #ifdef PNG_WRITE_SUPPORTED
1501 extern PNG_EXPORT(void,png_set_compression_buffer_size)
1502 PNGARG((png_structp png_ptr, png_uint_32 size));
1503 #endif
1504
1505 /* Reset the compression stream */
1506 extern PNG_EXPORT(int,png_reset_zstream) PNGARG((png_structp png_ptr));
1507
1508 /* New functions added in libpng-1.0.2 (not enabled by default until 1.2.0) */
1509 #ifdef PNG_USER_MEM_SUPPORTED
1510 extern PNG_EXPORT(png_structp,png_create_read_struct_2)
1511 PNGARG((png_const_charp user_png_ver, png_voidp error_ptr,
1512 png_error_ptr error_fn, png_error_ptr warn_fn, png_voidp mem_ptr,
1513 png_malloc_ptr malloc_fn, png_free_ptr free_fn));
1514 extern PNG_EXPORT(png_structp,png_create_write_struct_2)
1515 PNGARG((png_const_charp user_png_ver, png_voidp error_ptr,
1516 png_error_ptr error_fn, png_error_ptr warn_fn, png_voidp mem_ptr,
1517 png_malloc_ptr malloc_fn, png_free_ptr free_fn));
1518 #endif
1519
1520 /* Write a PNG chunk - size, type, (optional) data, CRC. */
1521 extern PNG_EXPORT(void,png_write_chunk) PNGARG((png_structp png_ptr,
1522 png_bytep chunk_name, png_bytep data, png_size_t length));
1523
1524 /* Write the start of a PNG chunk - length and chunk name. */
1525 extern PNG_EXPORT(void,png_write_chunk_start) PNGARG((png_structp png_ptr,
1526 png_bytep chunk_name, png_uint_32 length));
1527
1528 /* Write the data of a PNG chunk started with png_write_chunk_start(). */
1529 extern PNG_EXPORT(void,png_write_chunk_data) PNGARG((png_structp png_ptr,
1530 png_bytep data, png_size_t length));
1531
1532 /* Finish a chunk started with png_write_chunk_start() (includes CRC). */
1533 extern PNG_EXPORT(void,png_write_chunk_end) PNGARG((png_structp png_ptr));
1534
1535 /* Allocate and initialize the info structure */
1536 extern PNG_EXPORT(png_infop,png_create_info_struct)
1537 PNGARG((png_structp png_ptr));
1538
1539 #if defined(PNG_1_0_X) || defined (PNG_1_2_X)
1540 /* Initialize the info structure (old interface - DEPRECATED) */
1541 extern PNG_EXPORT(void,png_info_init) PNGARG((png_infop info_ptr));
1542 #undef png_info_init
1543 #define png_info_init(info_ptr) png_info_init_3(&info_ptr,\
1544 png_sizeof(png_info));
1545 #endif
1546
1547 extern PNG_EXPORT(void,png_info_init_3) PNGARG((png_infopp info_ptr,
1548 png_size_t png_info_struct_size));
1549
1550 /* Writes all the PNG information before the image. */
1551 extern PNG_EXPORT(void,png_write_info_before_PLTE) PNGARG((png_structp png_ptr,
1552 png_infop info_ptr));
1553 extern PNG_EXPORT(void,png_write_info) PNGARG((png_structp png_ptr,
1554 png_infop info_ptr));
1555
1556 #ifndef PNG_NO_SEQUENTIAL_READ_SUPPORTED
1557 /* read the information before the actual image data. */
1558 extern PNG_EXPORT(void,png_read_info) PNGARG((png_structp png_ptr,
1559 png_infop info_ptr));
1560 #endif
1561
1562 #if defined(PNG_TIME_RFC1123_SUPPORTED)
1563 extern PNG_EXPORT(png_charp,png_convert_to_rfc1123)
1564 PNGARG((png_structp png_ptr, png_timep ptime));
1565 #endif
1566
1567 #if !defined(_WIN32_WCE)
1568 /* "time.h" functions are not supported on WindowsCE */
1569 #if defined(PNG_WRITE_tIME_SUPPORTED)
1570 /* convert from a struct tm to png_time */
1571 extern PNG_EXPORT(void,png_convert_from_struct_tm) PNGARG((png_timep ptime,
1572 struct tm FAR * ttime));
1573
1574 /* convert from time_t to png_time. Uses gmtime() */
1575 extern PNG_EXPORT(void,png_convert_from_time_t) PNGARG((png_timep ptime,
1576 time_t ttime));
1577 #endif /* PNG_WRITE_tIME_SUPPORTED */
1578 #endif /* _WIN32_WCE */
1579
1580 #if defined(PNG_READ_EXPAND_SUPPORTED)
1581 /* Expand data to 24-bit RGB, or 8-bit grayscale, with alpha if available. */
1582 extern PNG_EXPORT(void,png_set_expand) PNGARG((png_structp png_ptr));
1583 #if !defined(PNG_1_0_X)
1584 extern PNG_EXPORT(void,png_set_expand_gray_1_2_4_to_8) PNGARG((png_structp
1585 png_ptr));
1586 #endif
1587 extern PNG_EXPORT(void,png_set_palette_to_rgb) PNGARG((png_structp png_ptr));
1588 extern PNG_EXPORT(void,png_set_tRNS_to_alpha) PNGARG((png_structp png_ptr));
1589 #if defined(PNG_1_0_X) || defined (PNG_1_2_X)
1590 /* Deprecated */
1591 extern PNG_EXPORT(void,png_set_gray_1_2_4_to_8) PNGARG((png_structp png_ptr));
1592 #endif
1593 #endif
1594
1595 #if defined(PNG_READ_BGR_SUPPORTED) || defined(PNG_WRITE_BGR_SUPPORTED)
1596 /* Use blue, green, red order for pixels. */
1597 extern PNG_EXPORT(void,png_set_bgr) PNGARG((png_structp png_ptr));
1598 #endif
1599
1600 #if defined(PNG_READ_GRAY_TO_RGB_SUPPORTED)
1601 /* Expand the grayscale to 24-bit RGB if necessary. */
1602 extern PNG_EXPORT(void,png_set_gray_to_rgb) PNGARG((png_structp png_ptr));
1603 #endif
1604
1605 #if defined(PNG_READ_RGB_TO_GRAY_SUPPORTED)
1606 /* Reduce RGB to grayscale. */
1607 #ifdef PNG_FLOATING_POINT_SUPPORTED
1608 extern PNG_EXPORT(void,png_set_rgb_to_gray) PNGARG((png_structp png_ptr,
1609 int error_action, double red, double green ));
1610 #endif
1611 extern PNG_EXPORT(void,png_set_rgb_to_gray_fixed) PNGARG((png_structp png_ptr,
1612 int error_action, png_fixed_point red, png_fixed_point green ));
1613 extern PNG_EXPORT(png_byte,png_get_rgb_to_gray_status) PNGARG((png_structp
1614 png_ptr));
1615 #endif
1616
1617 extern PNG_EXPORT(void,png_build_grayscale_palette) PNGARG((int bit_depth,
1618 png_colorp palette));
1619
1620 #if defined(PNG_READ_STRIP_ALPHA_SUPPORTED)
1621 extern PNG_EXPORT(void,png_set_strip_alpha) PNGARG((png_structp png_ptr));
1622 #endif
1623
1624 #if defined(PNG_READ_SWAP_ALPHA_SUPPORTED) || \
1625 defined(PNG_WRITE_SWAP_ALPHA_SUPPORTED)
1626 extern PNG_EXPORT(void,png_set_swap_alpha) PNGARG((png_structp png_ptr));
1627 #endif
1628
1629 #if defined(PNG_READ_INVERT_ALPHA_SUPPORTED) || \
1630 defined(PNG_WRITE_INVERT_ALPHA_SUPPORTED)
1631 extern PNG_EXPORT(void,png_set_invert_alpha) PNGARG((png_structp png_ptr));
1632 #endif
1633
1634 #if defined(PNG_READ_FILLER_SUPPORTED) || defined(PNG_WRITE_FILLER_SUPPORTED)
1635 /* Add a filler byte to 8-bit Gray or 24-bit RGB images. */
1636 extern PNG_EXPORT(void,png_set_filler) PNGARG((png_structp png_ptr,
1637 png_uint_32 filler, int flags));
1638 /* The values of the PNG_FILLER_ defines should NOT be changed */
1639 #define PNG_FILLER_BEFORE 0
1640 #define PNG_FILLER_AFTER 1
1641 /* Add an alpha byte to 8-bit Gray or 24-bit RGB images. */
1642 #if !defined(PNG_1_0_X)
1643 extern PNG_EXPORT(void,png_set_add_alpha) PNGARG((png_structp png_ptr,
1644 png_uint_32 filler, int flags));
1645 #endif
1646 #endif /* PNG_READ_FILLER_SUPPORTED || PNG_WRITE_FILLER_SUPPORTED */
1647
1648 #if defined(PNG_READ_SWAP_SUPPORTED) || defined(PNG_WRITE_SWAP_SUPPORTED)
1649 /* Swap bytes in 16-bit depth files. */
1650 extern PNG_EXPORT(void,png_set_swap) PNGARG((png_structp png_ptr));
1651 #endif
1652
1653 #if defined(PNG_READ_PACK_SUPPORTED) || defined(PNG_WRITE_PACK_SUPPORTED)
1654 /* Use 1 byte per pixel in 1, 2, or 4-bit depth files. */
1655 extern PNG_EXPORT(void,png_set_packing) PNGARG((png_structp png_ptr));
1656 #endif
1657
1658 #if defined(PNG_READ_PACKSWAP_SUPPORTED) || defined(PNG_WRITE_PACKSWAP_SUPPORTED)
1659 /* Swap packing order of pixels in bytes. */
1660 extern PNG_EXPORT(void,png_set_packswap) PNGARG((png_structp png_ptr));
1661 #endif
1662
1663 #if defined(PNG_READ_SHIFT_SUPPORTED) || defined(PNG_WRITE_SHIFT_SUPPORTED)
1664 /* Converts files to legal bit depths. */
1665 extern PNG_EXPORT(void,png_set_shift) PNGARG((png_structp png_ptr,
1666 png_color_8p true_bits));
1667 #endif
1668
1669 #if defined(PNG_READ_INTERLACING_SUPPORTED) || \
1670 defined(PNG_WRITE_INTERLACING_SUPPORTED)
1671 /* Have the code handle the interlacing. Returns the number of passes. */
1672 extern PNG_EXPORT(int,png_set_interlace_handling) PNGARG((png_structp png_ptr));
1673 #endif
1674
1675 #if defined(PNG_READ_INVERT_SUPPORTED) || defined(PNG_WRITE_INVERT_SUPPORTED)
1676 /* Invert monochrome files */
1677 extern PNG_EXPORT(void,png_set_invert_mono) PNGARG((png_structp png_ptr));
1678 #endif
1679
1680 #if defined(PNG_READ_BACKGROUND_SUPPORTED)
1681 /* Handle alpha and tRNS by replacing with a background color. */
1682 #ifdef PNG_FLOATING_POINT_SUPPORTED
1683 extern PNG_EXPORT(void,png_set_background) PNGARG((png_structp png_ptr,
1684 png_color_16p background_color, int background_gamma_code,
1685 int need_expand, double background_gamma));
1686 #endif
1687 #define PNG_BACKGROUND_GAMMA_UNKNOWN 0
1688 #define PNG_BACKGROUND_GAMMA_SCREEN 1
1689 #define PNG_BACKGROUND_GAMMA_FILE 2
1690 #define PNG_BACKGROUND_GAMMA_UNIQUE 3
1691 #endif
1692
1693 #if defined(PNG_READ_16_TO_8_SUPPORTED)
1694 /* strip the second byte of information from a 16-bit depth file. */
1695 extern PNG_EXPORT(void,png_set_strip_16) PNGARG((png_structp png_ptr));
1696 #endif
1697
1698 #if defined(PNG_READ_DITHER_SUPPORTED)
1699 /* Turn on dithering, and reduce the palette to the number of colors available. */
1700 extern PNG_EXPORT(void,png_set_dither) PNGARG((png_structp png_ptr,
1701 png_colorp palette, int num_palette, int maximum_colors,
1702 png_uint_16p histogram, int full_dither));
1703 #endif
1704
1705 #if defined(PNG_READ_GAMMA_SUPPORTED)
1706 /* Handle gamma correction. Screen_gamma=(display_exponent) */
1707 #ifdef PNG_FLOATING_POINT_SUPPORTED
1708 extern PNG_EXPORT(void,png_set_gamma) PNGARG((png_structp png_ptr,
1709 double screen_gamma, double default_file_gamma));
1710 #endif
1711 #endif
1712
1713 #if defined(PNG_1_0_X) || defined (PNG_1_2_X)
1714 #if defined(PNG_READ_EMPTY_PLTE_SUPPORTED) || \
1715 defined(PNG_WRITE_EMPTY_PLTE_SUPPORTED)
1716 /* Permit or disallow empty PLTE (0: not permitted, 1: permitted) */
1717 /* Deprecated and will be removed. Use png_permit_mng_features() instead. */
1718 extern PNG_EXPORT(void,png_permit_empty_plte) PNGARG((png_structp png_ptr,
1719 int empty_plte_permitted));
1720 #endif
1721 #endif
1722
1723 #if defined(PNG_WRITE_FLUSH_SUPPORTED)
1724 /* Set how many lines between output flushes - 0 for no flushing */
1725 extern PNG_EXPORT(void,png_set_flush) PNGARG((png_structp png_ptr, int nrows));
1726 /* Flush the current PNG output buffer */
1727 extern PNG_EXPORT(void,png_write_flush) PNGARG((png_structp png_ptr));
1728 #endif
1729
1730 /* optional update palette with requested transformations */
1731 extern PNG_EXPORT(void,png_start_read_image) PNGARG((png_structp png_ptr));
1732
1733 /* optional call to update the users info structure */
1734 extern PNG_EXPORT(void,png_read_update_info) PNGARG((png_structp png_ptr,
1735 png_infop info_ptr));
1736
1737 #ifndef PNG_NO_SEQUENTIAL_READ_SUPPORTED
1738 /* read one or more rows of image data. */
1739 extern PNG_EXPORT(void,png_read_rows) PNGARG((png_structp png_ptr,
1740 png_bytepp row, png_bytepp display_row, png_uint_32 num_rows));
1741 #endif
1742
1743 #ifndef PNG_NO_SEQUENTIAL_READ_SUPPORTED
1744 /* read a row of data. */
1745 extern PNG_EXPORT(void,png_read_row) PNGARG((png_structp png_ptr,
1746 png_bytep row,
1747 png_bytep display_row));
1748 #endif
1749
1750 #ifndef PNG_NO_SEQUENTIAL_READ_SUPPORTED
1751 /* read the whole image into memory at once. */
1752 extern PNG_EXPORT(void,png_read_image) PNGARG((png_structp png_ptr,
1753 png_bytepp image));
1754 #endif
1755
1756 /* write a row of image data */
1757 extern PNG_EXPORT(void,png_write_row) PNGARG((png_structp png_ptr,
1758 png_bytep row));
1759
1760 /* write a few rows of image data */
1761 extern PNG_EXPORT(void,png_write_rows) PNGARG((png_structp png_ptr,
1762 png_bytepp row, png_uint_32 num_rows));
1763
1764 /* write the image data */
1765 extern PNG_EXPORT(void,png_write_image) PNGARG((png_structp png_ptr,
1766 png_bytepp image));
1767
1768 /* writes the end of the PNG file. */
1769 extern PNG_EXPORT(void,png_write_end) PNGARG((png_structp png_ptr,
1770 png_infop info_ptr));
1771
1772 #ifndef PNG_NO_SEQUENTIAL_READ_SUPPORTED
1773 /* read the end of the PNG file. */
1774 extern PNG_EXPORT(void,png_read_end) PNGARG((png_structp png_ptr,
1775 png_infop info_ptr));
1776 #endif
1777
1778 /* free any memory associated with the png_info_struct */
1779 extern PNG_EXPORT(void,png_destroy_info_struct) PNGARG((png_structp png_ptr,
1780 png_infopp info_ptr_ptr));
1781
1782 /* free any memory associated with the png_struct and the png_info_structs */
1783 extern PNG_EXPORT(void,png_destroy_read_struct) PNGARG((png_structpp
1784 png_ptr_ptr, png_infopp info_ptr_ptr, png_infopp end_info_ptr_ptr));
1785
1786 /* free all memory used by the read (old method - NOT DLL EXPORTED) */
1787 extern void png_read_destroy PNGARG((png_structp png_ptr, png_infop info_ptr,
1788 png_infop end_info_ptr));
1789
1790 /* free any memory associated with the png_struct and the png_info_structs */
1791 extern PNG_EXPORT(void,png_destroy_write_struct)
1792 PNGARG((png_structpp png_ptr_ptr, png_infopp info_ptr_ptr));
1793
1794 /* free any memory used in png_ptr struct (old method - NOT DLL EXPORTED) */
1795 extern void png_write_destroy PNGARG((png_structp png_ptr));
1796
1797 /* set the libpng method of handling chunk CRC errors */
1798 extern PNG_EXPORT(void,png_set_crc_action) PNGARG((png_structp png_ptr,
1799 int crit_action, int ancil_action));
1800
1801 /* Values for png_set_crc_action() to say how to handle CRC errors in
1802 * ancillary and critical chunks, and whether to use the data contained
1803 * therein. Note that it is impossible to "discard" data in a critical
1804 * chunk. For versions prior to 0.90, the action was always error/quit,
1805 * whereas in version 0.90 and later, the action for CRC errors in ancillary
1806 * chunks is warn/discard. These values should NOT be changed.
1807 *
1808 * value action:critical action:ancillary
1809 */
1810 #define PNG_CRC_DEFAULT 0 /* error/quit warn/discard data */
1811 #define PNG_CRC_ERROR_QUIT 1 /* error/quit error/quit */
1812 #define PNG_CRC_WARN_DISCARD 2 /* (INVALID) warn/discard data */
1813 #define PNG_CRC_WARN_USE 3 /* warn/use data warn/use data */
1814 #define PNG_CRC_QUIET_USE 4 /* quiet/use data quiet/use data */
1815 #define PNG_CRC_NO_CHANGE 5 /* use current value use current value */
1816
1817 /* These functions give the user control over the scan-line filtering in
1818 * libpng and the compression methods used by zlib. These functions are
1819 * mainly useful for testing, as the defaults should work with most users.
1820 * Those users who are tight on memory or want faster performance at the
1821 * expense of compression can modify them. See the compression library
1822 * header file (zlib.h) for an explination of the compression functions.
1823 */
1824
1825 /* set the filtering method(s) used by libpng. Currently, the only valid
1826 * value for "method" is 0.
1827 */
1828 extern PNG_EXPORT(void,png_set_filter) PNGARG((png_structp png_ptr, int method,
1829 int filters));
1830
1831 /* Flags for png_set_filter() to say which filters to use. The flags
1832 * are chosen so that they don't conflict with real filter types
1833 * below, in case they are supplied instead of the #defined constants.
1834 * These values should NOT be changed.
1835 */
1836 #define PNG_NO_FILTERS 0x00
1837 #define PNG_FILTER_NONE 0x08
1838 #define PNG_FILTER_SUB 0x10
1839 #define PNG_FILTER_UP 0x20
1840 #define PNG_FILTER_AVG 0x40
1841 #define PNG_FILTER_PAETH 0x80
1842 #define PNG_ALL_FILTERS (PNG_FILTER_NONE | PNG_FILTER_SUB | PNG_FILTER_UP | \
1843 PNG_FILTER_AVG | PNG_FILTER_PAETH)
1844
1845 /* Filter values (not flags) - used in pngwrite.c, pngwutil.c for now.
1846 * These defines should NOT be changed.
1847 */
1848 #define PNG_FILTER_VALUE_NONE 0
1849 #define PNG_FILTER_VALUE_SUB 1
1850 #define PNG_FILTER_VALUE_UP 2
1851 #define PNG_FILTER_VALUE_AVG 3
1852 #define PNG_FILTER_VALUE_PAETH 4
1853 #define PNG_FILTER_VALUE_LAST 5
1854
1855 #if defined(PNG_WRITE_WEIGHTED_FILTER_SUPPORTED) /* EXPERIMENTAL */
1856 /* The "heuristic_method" is given by one of the PNG_FILTER_HEURISTIC_
1857 * defines, either the default (minimum-sum-of-absolute-differences), or
1858 * the experimental method (weighted-minimum-sum-of-absolute-differences).
1859 *
1860 * Weights are factors >= 1.0, indicating how important it is to keep the
1861 * filter type consistent between rows. Larger numbers mean the current
1862 * filter is that many times as likely to be the same as the "num_weights"
1863 * previous filters. This is cumulative for each previous row with a weight.
1864 * There needs to be "num_weights" values in "filter_weights", or it can be
1865 * NULL if the weights aren't being specified. Weights have no influence on
1866 * the selection of the first row filter. Well chosen weights can (in theory)
1867 * improve the compression for a given image.
1868 *
1869 * Costs are factors >= 1.0 indicating the relative decoding costs of a
1870 * filter type. Higher costs indicate more decoding expense, and are
1871 * therefore less likely to be selected over a filter with lower computational
1872 * costs. There needs to be a value in "filter_costs" for each valid filter
1873 * type (given by PNG_FILTER_VALUE_LAST), or it can be NULL if you aren't
1874 * setting the costs. Costs try to improve the speed of decompression without
1875 * unduly increasing the compressed image size.
1876 *
1877 * A negative weight or cost indicates the default value is to be used, and
1878 * values in the range [0.0, 1.0) indicate the value is to remain unchanged.
1879 * The default values for both weights and costs are currently 1.0, but may
1880 * change if good general weighting/cost heuristics can be found. If both
1881 * the weights and costs are set to 1.0, this degenerates the WEIGHTED method
1882 * to the UNWEIGHTED method, but with added encoding time/computation.
1883 */
1884 #ifdef PNG_FLOATING_POINT_SUPPORTED
1885 extern PNG_EXPORT(void,png_set_filter_heuristics) PNGARG((png_structp png_ptr,
1886 int heuristic_method, int num_weights, png_doublep filter_weights,
1887 png_doublep filter_costs));
1888 #endif
1889 #endif /* PNG_WRITE_WEIGHTED_FILTER_SUPPORTED */
1890
1891 /* Heuristic used for row filter selection. These defines should NOT be
1892 * changed.
1893 */
1894 #define PNG_FILTER_HEURISTIC_DEFAULT 0 /* Currently "UNWEIGHTED" */
1895 #define PNG_FILTER_HEURISTIC_UNWEIGHTED 1 /* Used by libpng < 0.95 */
1896 #define PNG_FILTER_HEURISTIC_WEIGHTED 2 /* Experimental feature */
1897 #define PNG_FILTER_HEURISTIC_LAST 3 /* Not a valid value */
1898
1899 /* Set the library compression level. Currently, valid values range from
1900 * 0 - 9, corresponding directly to the zlib compression levels 0 - 9
1901 * (0 - no compression, 9 - "maximal" compression). Note that tests have
1902 * shown that zlib compression levels 3-6 usually perform as well as level 9
1903 * for PNG images, and do considerably fewer caclulations. In the future,
1904 * these values may not correspond directly to the zlib compression levels.
1905 */
1906 extern PNG_EXPORT(void,png_set_compression_level) PNGARG((png_structp png_ptr,
1907 int level));
1908
1909 extern PNG_EXPORT(void,png_set_compression_mem_level)
1910 PNGARG((png_structp png_ptr, int mem_level));
1911
1912 extern PNG_EXPORT(void,png_set_compression_strategy)
1913 PNGARG((png_structp png_ptr, int strategy));
1914
1915 extern PNG_EXPORT(void,png_set_compression_window_bits)
1916 PNGARG((png_structp png_ptr, int window_bits));
1917
1918 extern PNG_EXPORT(void,png_set_compression_method) PNGARG((png_structp png_ptr,
1919 int method));
1920
1921 /* These next functions are called for input/output, memory, and error
1922 * handling. They are in the file pngrio.c, pngwio.c, and pngerror.c,
1923 * and call standard C I/O routines such as fread(), fwrite(), and
1924 * fprintf(). These functions can be made to use other I/O routines
1925 * at run time for those applications that need to handle I/O in a
1926 * different manner by calling png_set_???_fn(). See libpng.txt for
1927 * more information.
1928 */
1929
1930 #if !defined(PNG_NO_STDIO)
1931 /* Initialize the input/output for the PNG file to the default functions. */
1932 extern PNG_EXPORT(void,png_init_io) PNGARG((png_structp png_ptr, png_FILE_p fp));
1933 #endif
1934
1935 /* Replace the (error and abort), and warning functions with user
1936 * supplied functions. If no messages are to be printed you must still
1937 * write and use replacement functions. The replacement error_fn should
1938 * still do a longjmp to the last setjmp location if you are using this
1939 * method of error handling. If error_fn or warning_fn is NULL, the
1940 * default function will be used.
1941 */
1942
1943 extern PNG_EXPORT(void,png_set_error_fn) PNGARG((png_structp png_ptr,
1944 png_voidp error_ptr, png_error_ptr error_fn, png_error_ptr warning_fn));
1945
1946 /* Return the user pointer associated with the error functions */
1947 extern PNG_EXPORT(png_voidp,png_get_error_ptr) PNGARG((png_structp png_ptr));
1948
1949 /* Replace the default data output functions with a user supplied one(s).
1950 * If buffered output is not used, then output_flush_fn can be set to NULL.
1951 * If PNG_WRITE_FLUSH_SUPPORTED is not defined at libpng compile time
1952 * output_flush_fn will be ignored (and thus can be NULL).
1953 */
1954 extern PNG_EXPORT(void,png_set_write_fn) PNGARG((png_structp png_ptr,
1955 png_voidp io_ptr, png_rw_ptr write_data_fn, png_flush_ptr output_flush_fn));
1956
1957 /* Replace the default data input function with a user supplied one. */
1958 extern PNG_EXPORT(void,png_set_read_fn) PNGARG((png_structp png_ptr,
1959 png_voidp io_ptr, png_rw_ptr read_data_fn));
1960
1961 /* Return the user pointer associated with the I/O functions */
1962 extern PNG_EXPORT(png_voidp,png_get_io_ptr) PNGARG((png_structp png_ptr));
1963
1964 extern PNG_EXPORT(void,png_set_read_status_fn) PNGARG((png_structp png_ptr,
1965 png_read_status_ptr read_row_fn));
1966
1967 extern PNG_EXPORT(void,png_set_write_status_fn) PNGARG((png_structp png_ptr,
1968 png_write_status_ptr write_row_fn));
1969
1970 #ifdef PNG_USER_MEM_SUPPORTED
1971 /* Replace the default memory allocation functions with user supplied one(s). */
1972 extern PNG_EXPORT(void,png_set_mem_fn) PNGARG((png_structp png_ptr,
1973 png_voidp mem_ptr, png_malloc_ptr malloc_fn, png_free_ptr free_fn));
1974 /* Return the user pointer associated with the memory functions */
1975 extern PNG_EXPORT(png_voidp,png_get_mem_ptr) PNGARG((png_structp png_ptr));
1976 #endif
1977
1978 #if defined(PNG_READ_USER_TRANSFORM_SUPPORTED) || \
1979 defined(PNG_LEGACY_SUPPORTED)
1980 extern PNG_EXPORT(void,png_set_read_user_transform_fn) PNGARG((png_structp
1981 png_ptr, png_user_transform_ptr read_user_transform_fn));
1982 #endif
1983
1984 #if defined(PNG_WRITE_USER_TRANSFORM_SUPPORTED) || \
1985 defined(PNG_LEGACY_SUPPORTED)
1986 extern PNG_EXPORT(void,png_set_write_user_transform_fn) PNGARG((png_structp
1987 png_ptr, png_user_transform_ptr write_user_transform_fn));
1988 #endif
1989
1990 #if defined(PNG_READ_USER_TRANSFORM_SUPPORTED) || \
1991 defined(PNG_WRITE_USER_TRANSFORM_SUPPORTED) || \
1992 defined(PNG_LEGACY_SUPPORTED)
1993 extern PNG_EXPORT(void,png_set_user_transform_info) PNGARG((png_structp
1994 png_ptr, png_voidp user_transform_ptr, int user_transform_depth,
1995 int user_transform_channels));
1996 /* Return the user pointer associated with the user transform functions */
1997 extern PNG_EXPORT(png_voidp,png_get_user_transform_ptr)
1998 PNGARG((png_structp png_ptr));
1999 #endif
2000
2001 #ifdef PNG_USER_CHUNKS_SUPPORTED
2002 extern PNG_EXPORT(void,png_set_read_user_chunk_fn) PNGARG((png_structp png_ptr,
2003 png_voidp user_chunk_ptr, png_user_chunk_ptr read_user_chunk_fn));
2004 extern PNG_EXPORT(png_voidp,png_get_user_chunk_ptr) PNGARG((png_structp
2005 png_ptr));
2006 #endif
2007
2008 #ifdef PNG_PROGRESSIVE_READ_SUPPORTED
2009 /* Sets the function callbacks for the push reader, and a pointer to a
2010 * user-defined structure available to the callback functions.
2011 */
2012 extern PNG_EXPORT(void,png_set_progressive_read_fn) PNGARG((png_structp png_ptr,
2013 png_voidp progressive_ptr,
2014 png_progressive_info_ptr info_fn, png_progressive_row_ptr row_fn,
2015 png_progressive_end_ptr end_fn));
2016
2017 /* returns the user pointer associated with the push read functions */
2018 extern PNG_EXPORT(png_voidp,png_get_progressive_ptr)
2019 PNGARG((png_structp png_ptr));
2020
2021 /* function to be called when data becomes available */
2022 extern PNG_EXPORT(void,png_process_data) PNGARG((png_structp png_ptr,
2023 png_infop info_ptr, png_bytep buffer, png_size_t buffer_size));
2024
2025 /* function that combines rows. Not very much different than the
2026 * png_combine_row() call. Is this even used?????
2027 */
2028 extern PNG_EXPORT(void,png_progressive_combine_row) PNGARG((png_structp png_ptr,
2029 png_bytep old_row, png_bytep new_row));
2030 #endif /* PNG_PROGRESSIVE_READ_SUPPORTED */
2031
2032 extern PNG_EXPORT(png_voidp,png_malloc) PNGARG((png_structp png_ptr,
2033 png_uint_32 size));
2034
2035 #if defined(PNG_1_0_X)
2036 # define png_malloc_warn png_malloc
2037 #else
2038 /* Added at libpng version 1.2.4 */
2039 extern PNG_EXPORT(png_voidp,png_malloc_warn) PNGARG((png_structp png_ptr,
2040 png_uint_32 size));
2041 #endif
2042
2043 /* frees a pointer allocated by png_malloc() */
2044 extern PNG_EXPORT(void,png_free) PNGARG((png_structp png_ptr, png_voidp ptr));
2045
2046 #if defined(PNG_1_0_X)
2047 /* Function to allocate memory for zlib. */
2048 extern PNG_EXPORT(voidpf,png_zalloc) PNGARG((voidpf png_ptr, uInt items,
2049 uInt size));
2050
2051 /* Function to free memory for zlib */
2052 extern PNG_EXPORT(void,png_zfree) PNGARG((voidpf png_ptr, voidpf ptr));
2053 #endif
2054
2055 /* Free data that was allocated internally */
2056 extern PNG_EXPORT(void,png_free_data) PNGARG((png_structp png_ptr,
2057 png_infop info_ptr, png_uint_32 free_me, int num));
2058 #ifdef PNG_FREE_ME_SUPPORTED
2059 /* Reassign responsibility for freeing existing data, whether allocated
2060 * by libpng or by the application */
2061 extern PNG_EXPORT(void,png_data_freer) PNGARG((png_structp png_ptr,
2062 png_infop info_ptr, int freer, png_uint_32 mask));
2063 #endif
2064 /* assignments for png_data_freer */
2065 #define PNG_DESTROY_WILL_FREE_DATA 1
2066 #define PNG_SET_WILL_FREE_DATA 1
2067 #define PNG_USER_WILL_FREE_DATA 2
2068 /* Flags for png_ptr->free_me and info_ptr->free_me */
2069 #define PNG_FREE_HIST 0x0008
2070 #define PNG_FREE_ICCP 0x0010
2071 #define PNG_FREE_SPLT 0x0020
2072 #define PNG_FREE_ROWS 0x0040
2073 #define PNG_FREE_PCAL 0x0080
2074 #define PNG_FREE_SCAL 0x0100
2075 #define PNG_FREE_UNKN 0x0200
2076 #define PNG_FREE_LIST 0x0400
2077 #define PNG_FREE_PLTE 0x1000
2078 #define PNG_FREE_TRNS 0x2000
2079 #define PNG_FREE_TEXT 0x4000
2080 #define PNG_FREE_ALL 0x7fff
2081 #define PNG_FREE_MUL 0x4220 /* PNG_FREE_SPLT|PNG_FREE_TEXT|PNG_FREE_UNKN */
2082
2083 #ifdef PNG_USER_MEM_SUPPORTED
2084 extern PNG_EXPORT(png_voidp,png_malloc_default) PNGARG((png_structp png_ptr,
2085 png_uint_32 size));
2086 extern PNG_EXPORT(void,png_free_default) PNGARG((png_structp png_ptr,
2087 png_voidp ptr));
2088 #endif
2089
2090 extern PNG_EXPORT(png_voidp,png_memcpy_check) PNGARG((png_structp png_ptr,
2091 png_voidp s1, png_voidp s2, png_uint_32 size));
2092
2093 extern PNG_EXPORT(png_voidp,png_memset_check) PNGARG((png_structp png_ptr,
2094 png_voidp s1, int value, png_uint_32 size));
2095
2096 #if defined(USE_FAR_KEYWORD) /* memory model conversion function */
2097 extern void *png_far_to_near PNGARG((png_structp png_ptr,png_voidp ptr,
2098 int check));
2099 #endif /* USE_FAR_KEYWORD */
2100
2101 #ifndef PNG_NO_ERROR_TEXT
2102 /* Fatal error in PNG image of libpng - can't continue */
2103 extern PNG_EXPORT(void,png_error) PNGARG((png_structp png_ptr,
2104 png_const_charp error_message));
2105
2106 /* The same, but the chunk name is prepended to the error string. */
2107 extern PNG_EXPORT(void,png_chunk_error) PNGARG((png_structp png_ptr,
2108 png_const_charp error_message));
2109 #else
2110 /* Fatal error in PNG image of libpng - can't continue */
2111 extern PNG_EXPORT(void,png_err) PNGARG((png_structp png_ptr));
2112 #endif
2113
2114 #ifndef PNG_NO_WARNINGS
2115 /* Non-fatal error in libpng. Can continue, but may have a problem. */
2116 extern PNG_EXPORT(void,png_warning) PNGARG((png_structp png_ptr,
2117 png_const_charp warning_message));
2118
2119 #ifdef PNG_READ_SUPPORTED
2120 /* Non-fatal error in libpng, chunk name is prepended to message. */
2121 extern PNG_EXPORT(void,png_chunk_warning) PNGARG((png_structp png_ptr,
2122 png_const_charp warning_message));
2123 #endif /* PNG_READ_SUPPORTED */
2124 #endif /* PNG_NO_WARNINGS */
2125
2126 /* The png_set_<chunk> functions are for storing values in the png_info_struct.
2127 * Similarly, the png_get_<chunk> calls are used to read values from the
2128 * png_info_struct, either storing the parameters in the passed variables, or
2129 * setting pointers into the png_info_struct where the data is stored. The
2130 * png_get_<chunk> functions return a non-zero value if the data was available
2131 * in info_ptr, or return zero and do not change any of the parameters if the
2132 * data was not available.
2133 *
2134 * These functions should be used instead of directly accessing png_info
2135 * to avoid problems with future changes in the size and internal layout of
2136 * png_info_struct.
2137 */
2138 /* Returns "flag" if chunk data is valid in info_ptr. */
2139 extern PNG_EXPORT(png_uint_32,png_get_valid) PNGARG((png_structp png_ptr,
2140 png_infop info_ptr, png_uint_32 flag));
2141
2142 /* Returns number of bytes needed to hold a transformed row. */
2143 extern PNG_EXPORT(png_uint_32,png_get_rowbytes) PNGARG((png_structp png_ptr,
2144 png_infop info_ptr));
2145
2146 #if defined(PNG_INFO_IMAGE_SUPPORTED)
2147 /* Returns row_pointers, which is an array of pointers to scanlines that was
2148 returned from png_read_png(). */
2149 extern PNG_EXPORT(png_bytepp,png_get_rows) PNGARG((png_structp png_ptr,
2150 png_infop info_ptr));
2151 /* Set row_pointers, which is an array of pointers to scanlines for use
2152 by png_write_png(). */
2153 extern PNG_EXPORT(void,png_set_rows) PNGARG((png_structp png_ptr,
2154 png_infop info_ptr, png_bytepp row_pointers));
2155 #endif
2156
2157 /* Returns number of color channels in image. */
2158 extern PNG_EXPORT(png_byte,png_get_channels) PNGARG((png_structp png_ptr,
2159 png_infop info_ptr));
2160
2161 #ifdef PNG_EASY_ACCESS_SUPPORTED
2162 /* Returns image width in pixels. */
2163 extern PNG_EXPORT(png_uint_32, png_get_image_width) PNGARG((png_structp
2164 png_ptr, png_infop info_ptr));
2165
2166 /* Returns image height in pixels. */
2167 extern PNG_EXPORT(png_uint_32, png_get_image_height) PNGARG((png_structp
2168 png_ptr, png_infop info_ptr));
2169
2170 /* Returns image bit_depth. */
2171 extern PNG_EXPORT(png_byte, png_get_bit_depth) PNGARG((png_structp
2172 png_ptr, png_infop info_ptr));
2173
2174 /* Returns image color_type. */
2175 extern PNG_EXPORT(png_byte, png_get_color_type) PNGARG((png_structp
2176 png_ptr, png_infop info_ptr));
2177
2178 /* Returns image filter_type. */
2179 extern PNG_EXPORT(png_byte, png_get_filter_type) PNGARG((png_structp
2180 png_ptr, png_infop info_ptr));
2181
2182 /* Returns image interlace_type. */
2183 extern PNG_EXPORT(png_byte, png_get_interlace_type) PNGARG((png_structp
2184 png_ptr, png_infop info_ptr));
2185
2186 /* Returns image compression_type. */
2187 extern PNG_EXPORT(png_byte, png_get_compression_type) PNGARG((png_structp
2188 png_ptr, png_infop info_ptr));
2189
2190 /* Returns image resolution in pixels per meter, from pHYs chunk data. */
2191 extern PNG_EXPORT(png_uint_32, png_get_pixels_per_meter) PNGARG((png_structp
2192 png_ptr, png_infop info_ptr));
2193 extern PNG_EXPORT(png_uint_32, png_get_x_pixels_per_meter) PNGARG((png_structp
2194 png_ptr, png_infop info_ptr));
2195 extern PNG_EXPORT(png_uint_32, png_get_y_pixels_per_meter) PNGARG((png_structp
2196 png_ptr, png_infop info_ptr));
2197
2198 /* Returns pixel aspect ratio, computed from pHYs chunk data. */
2199 #ifdef PNG_FLOATING_POINT_SUPPORTED
2200 extern PNG_EXPORT(float, png_get_pixel_aspect_ratio) PNGARG((png_structp
2201 png_ptr, png_infop info_ptr));
2202 #endif
2203
2204 /* Returns image x, y offset in pixels or microns, from oFFs chunk data. */
2205 extern PNG_EXPORT(png_int_32, png_get_x_offset_pixels) PNGARG((png_structp
2206 png_ptr, png_infop info_ptr));
2207 extern PNG_EXPORT(png_int_32, png_get_y_offset_pixels) PNGARG((png_structp
2208 png_ptr, png_infop info_ptr));
2209 extern PNG_EXPORT(png_int_32, png_get_x_offset_microns) PNGARG((png_structp
2210 png_ptr, png_infop info_ptr));
2211 extern PNG_EXPORT(png_int_32, png_get_y_offset_microns) PNGARG((png_structp
2212 png_ptr, png_infop info_ptr));
2213
2214 #endif /* PNG_EASY_ACCESS_SUPPORTED */
2215
2216 /* Returns pointer to signature string read from PNG header */
2217 extern PNG_EXPORT(png_bytep,png_get_signature) PNGARG((png_structp png_ptr,
2218 png_infop info_ptr));
2219
2220 #if defined(PNG_bKGD_SUPPORTED)
2221 extern PNG_EXPORT(png_uint_32,png_get_bKGD) PNGARG((png_structp png_ptr,
2222 png_infop info_ptr, png_color_16p *background));
2223 #endif
2224
2225 #if defined(PNG_bKGD_SUPPORTED)
2226 extern PNG_EXPORT(void,png_set_bKGD) PNGARG((png_structp png_ptr,
2227 png_infop info_ptr, png_color_16p background));
2228 #endif
2229
2230 #if defined(PNG_cHRM_SUPPORTED)
2231 #ifdef PNG_FLOATING_POINT_SUPPORTED
2232 extern PNG_EXPORT(png_uint_32,png_get_cHRM) PNGARG((png_structp png_ptr,
2233 png_infop info_ptr, double *white_x, double *white_y, double *red_x,
2234 double *red_y, double *green_x, double *green_y, double *blue_x,
2235 double *blue_y));
2236 #endif
2237 #ifdef PNG_FIXED_POINT_SUPPORTED
2238 extern PNG_EXPORT(png_uint_32,png_get_cHRM_fixed) PNGARG((png_structp png_ptr,
2239 png_infop info_ptr, png_fixed_point *int_white_x, png_fixed_point
2240 *int_white_y, png_fixed_point *int_red_x, png_fixed_point *int_red_y,
2241 png_fixed_point *int_green_x, png_fixed_point *int_green_y, png_fixed_point
2242 *int_blue_x, png_fixed_point *int_blue_y));
2243 #endif
2244 #endif
2245
2246 #if defined(PNG_cHRM_SUPPORTED)
2247 #ifdef PNG_FLOATING_POINT_SUPPORTED
2248 extern PNG_EXPORT(void,png_set_cHRM) PNGARG((png_structp png_ptr,
2249 png_infop info_ptr, double white_x, double white_y, double red_x,
2250 double red_y, double green_x, double green_y, double blue_x, double blue_y));
2251 #endif
2252 #ifdef PNG_FIXED_POINT_SUPPORTED
2253 extern PNG_EXPORT(void,png_set_cHRM_fixed) PNGARG((png_structp png_ptr,
2254 png_infop info_ptr, png_fixed_point int_white_x, png_fixed_point int_white_y,
2255 png_fixed_point int_red_x, png_fixed_point int_red_y, png_fixed_point
2256 int_green_x, png_fixed_point int_green_y, png_fixed_point int_blue_x,
2257 png_fixed_point int_blue_y));
2258 #endif
2259 #endif
2260
2261 #if defined(PNG_gAMA_SUPPORTED)
2262 #ifdef PNG_FLOATING_POINT_SUPPORTED
2263 extern PNG_EXPORT(png_uint_32,png_get_gAMA) PNGARG((png_structp png_ptr,
2264 png_infop info_ptr, double *file_gamma));
2265 #endif
2266 extern PNG_EXPORT(png_uint_32,png_get_gAMA_fixed) PNGARG((png_structp png_ptr,
2267 png_infop info_ptr, png_fixed_point *int_file_gamma));
2268 #endif
2269
2270 #if defined(PNG_gAMA_SUPPORTED)
2271 #ifdef PNG_FLOATING_POINT_SUPPORTED
2272 extern PNG_EXPORT(void,png_set_gAMA) PNGARG((png_structp png_ptr,
2273 png_infop info_ptr, double file_gamma));
2274 #endif
2275 extern PNG_EXPORT(void,png_set_gAMA_fixed) PNGARG((png_structp png_ptr,
2276 png_infop info_ptr, png_fixed_point int_file_gamma));
2277 #endif
2278
2279 #if defined(PNG_hIST_SUPPORTED)
2280 extern PNG_EXPORT(png_uint_32,png_get_hIST) PNGARG((png_structp png_ptr,
2281 png_infop info_ptr, png_uint_16p *hist));
2282 #endif
2283
2284 #if defined(PNG_hIST_SUPPORTED)
2285 extern PNG_EXPORT(void,png_set_hIST) PNGARG((png_structp png_ptr,
2286 png_infop info_ptr, png_uint_16p hist));
2287 #endif
2288
2289 extern PNG_EXPORT(png_uint_32,png_get_IHDR) PNGARG((png_structp png_ptr,
2290 png_infop info_ptr, png_uint_32 *width, png_uint_32 *height,
2291 int *bit_depth, int *color_type, int *interlace_method,
2292 int *compression_method, int *filter_method));
2293
2294 extern PNG_EXPORT(void,png_set_IHDR) PNGARG((png_structp png_ptr,
2295 png_infop info_ptr, png_uint_32 width, png_uint_32 height, int bit_depth,
2296 int color_type, int interlace_method, int compression_method,
2297 int filter_method));
2298
2299 #if defined(PNG_oFFs_SUPPORTED)
2300 extern PNG_EXPORT(png_uint_32,png_get_oFFs) PNGARG((png_structp png_ptr,
2301 png_infop info_ptr, png_int_32 *offset_x, png_int_32 *offset_y,
2302 int *unit_type));
2303 #endif
2304
2305 #if defined(PNG_oFFs_SUPPORTED)
2306 extern PNG_EXPORT(void,png_set_oFFs) PNGARG((png_structp png_ptr,
2307 png_infop info_ptr, png_int_32 offset_x, png_int_32 offset_y,
2308 int unit_type));
2309 #endif
2310
2311 #if defined(PNG_pCAL_SUPPORTED)
2312 extern PNG_EXPORT(png_uint_32,png_get_pCAL) PNGARG((png_structp png_ptr,
2313 png_infop info_ptr, png_charp *purpose, png_int_32 *X0, png_int_32 *X1,
2314 int *type, int *nparams, png_charp *units, png_charpp *params));
2315 #endif
2316
2317 #if defined(PNG_pCAL_SUPPORTED)
2318 extern PNG_EXPORT(void,png_set_pCAL) PNGARG((png_structp png_ptr,
2319 png_infop info_ptr, png_charp purpose, png_int_32 X0, png_int_32 X1,
2320 int type, int nparams, png_charp units, png_charpp params));
2321 #endif
2322
2323 #if defined(PNG_pHYs_SUPPORTED)
2324 extern PNG_EXPORT(png_uint_32,png_get_pHYs) PNGARG((png_structp png_ptr,
2325 png_infop info_ptr, png_uint_32 *res_x, png_uint_32 *res_y, int *unit_type));
2326 #endif
2327
2328 #if defined(PNG_pHYs_SUPPORTED)
2329 extern PNG_EXPORT(void,png_set_pHYs) PNGARG((png_structp png_ptr,
2330 png_infop info_ptr, png_uint_32 res_x, png_uint_32 res_y, int unit_type));
2331 #endif
2332
2333 extern PNG_EXPORT(png_uint_32,png_get_PLTE) PNGARG((png_structp png_ptr,
2334 png_infop info_ptr, png_colorp *palette, int *num_palette));
2335
2336 extern PNG_EXPORT(void,png_set_PLTE) PNGARG((png_structp png_ptr,
2337 png_infop info_ptr, png_colorp palette, int num_palette));
2338
2339 #if defined(PNG_sBIT_SUPPORTED)
2340 extern PNG_EXPORT(png_uint_32,png_get_sBIT) PNGARG((png_structp png_ptr,
2341 png_infop info_ptr, png_color_8p *sig_bit));
2342 #endif
2343
2344 #if defined(PNG_sBIT_SUPPORTED)
2345 extern PNG_EXPORT(void,png_set_sBIT) PNGARG((png_structp png_ptr,
2346 png_infop info_ptr, png_color_8p sig_bit));
2347 #endif
2348
2349 #if defined(PNG_sRGB_SUPPORTED)
2350 extern PNG_EXPORT(png_uint_32,png_get_sRGB) PNGARG((png_structp png_ptr,
2351 png_infop info_ptr, int *intent));
2352 #endif
2353
2354 #if defined(PNG_sRGB_SUPPORTED)
2355 extern PNG_EXPORT(void,png_set_sRGB) PNGARG((png_structp png_ptr,
2356 png_infop info_ptr, int intent));
2357 extern PNG_EXPORT(void,png_set_sRGB_gAMA_and_cHRM) PNGARG((png_structp png_ptr,
2358 png_infop info_ptr, int intent));
2359 #endif
2360
2361 #if defined(PNG_iCCP_SUPPORTED)
2362 extern PNG_EXPORT(png_uint_32,png_get_iCCP) PNGARG((png_structp png_ptr,
2363 png_infop info_ptr, png_charpp name, int *compression_type,
2364 png_charpp profile, png_uint_32 *proflen));
2365 /* Note to maintainer: profile should be png_bytepp */
2366 #endif
2367
2368 #if defined(PNG_iCCP_SUPPORTED)
2369 extern PNG_EXPORT(void,png_set_iCCP) PNGARG((png_structp png_ptr,
2370 png_infop info_ptr, png_charp name, int compression_type,
2371 png_charp profile, png_uint_32 proflen));
2372 /* Note to maintainer: profile should be png_bytep */
2373 #endif
2374
2375 #if defined(PNG_sPLT_SUPPORTED)
2376 extern PNG_EXPORT(png_uint_32,png_get_sPLT) PNGARG((png_structp png_ptr,
2377 png_infop info_ptr, png_sPLT_tpp entries));
2378 #endif
2379
2380 #if defined(PNG_sPLT_SUPPORTED)
2381 extern PNG_EXPORT(void,png_set_sPLT) PNGARG((png_structp png_ptr,
2382 png_infop info_ptr, png_sPLT_tp entries, int nentries));
2383 #endif
2384
2385 #if defined(PNG_TEXT_SUPPORTED)
2386 /* png_get_text also returns the number of text chunks in *num_text */
2387 extern PNG_EXPORT(png_uint_32,png_get_text) PNGARG((png_structp png_ptr,
2388 png_infop info_ptr, png_textp *text_ptr, int *num_text));
2389 #endif
2390
2391 /*
2392 * Note while png_set_text() will accept a structure whose text,
2393 * language, and translated keywords are NULL pointers, the structure
2394 * returned by png_get_text will always contain regular
2395 * zero-terminated C strings. They might be empty strings but
2396 * they will never be NULL pointers.
2397 */
2398
2399 #if defined(PNG_TEXT_SUPPORTED)
2400 extern PNG_EXPORT(void,png_set_text) PNGARG((png_structp png_ptr,
2401 png_infop info_ptr, png_textp text_ptr, int num_text));
2402 #endif
2403
2404 #if defined(PNG_tIME_SUPPORTED)
2405 extern PNG_EXPORT(png_uint_32,png_get_tIME) PNGARG((png_structp png_ptr,
2406 png_infop info_ptr, png_timep *mod_time));
2407 #endif
2408
2409 #if defined(PNG_tIME_SUPPORTED)
2410 extern PNG_EXPORT(void,png_set_tIME) PNGARG((png_structp png_ptr,
2411 png_infop info_ptr, png_timep mod_time));
2412 #endif
2413
2414 #if defined(PNG_tRNS_SUPPORTED)
2415 extern PNG_EXPORT(png_uint_32,png_get_tRNS) PNGARG((png_structp png_ptr,
2416 png_infop info_ptr, png_bytep *trans, int *num_trans,
2417 png_color_16p *trans_values));
2418 #endif
2419
2420 #if defined(PNG_tRNS_SUPPORTED)
2421 extern PNG_EXPORT(void,png_set_tRNS) PNGARG((png_structp png_ptr,
2422 png_infop info_ptr, png_bytep trans, int num_trans,
2423 png_color_16p trans_values));
2424 #endif
2425
2426 #if defined(PNG_tRNS_SUPPORTED)
2427 #endif
2428
2429 #if defined(PNG_sCAL_SUPPORTED)
2430 #ifdef PNG_FLOATING_POINT_SUPPORTED
2431 extern PNG_EXPORT(png_uint_32,png_get_sCAL) PNGARG((png_structp png_ptr,
2432 png_infop info_ptr, int *unit, double *width, double *height));
2433 #else
2434 #ifdef PNG_FIXED_POINT_SUPPORTED
2435 extern PNG_EXPORT(png_uint_32,png_get_sCAL_s) PNGARG((png_structp png_ptr,
2436 png_infop info_ptr, int *unit, png_charpp swidth, png_charpp sheight));
2437 #endif
2438 #endif
2439 #endif /* PNG_sCAL_SUPPORTED */
2440
2441 #if defined(PNG_sCAL_SUPPORTED)
2442 #ifdef PNG_FLOATING_POINT_SUPPORTED
2443 extern PNG_EXPORT(void,png_set_sCAL) PNGARG((png_structp png_ptr,
2444 png_infop info_ptr, int unit, double width, double height));
2445 #else
2446 #ifdef PNG_FIXED_POINT_SUPPORTED
2447 extern PNG_EXPORT(void,png_set_sCAL_s) PNGARG((png_structp png_ptr,
2448 png_infop info_ptr, int unit, png_charp swidth, png_charp sheight));
2449 #endif
2450 #endif
2451 #endif /* PNG_sCAL_SUPPORTED || PNG_WRITE_sCAL_SUPPORTED */
2452
2453 #if defined(PNG_UNKNOWN_CHUNKS_SUPPORTED)
2454 /* provide a list of chunks and how they are to be handled, if the built-in
2455 handling or default unknown chunk handling is not desired. Any chunks not
2456 listed will be handled in the default manner. The IHDR and IEND chunks
2457 must not be listed.
2458 keep = 0: follow default behaviour
2459 = 1: do not keep
2460 = 2: keep only if safe-to-copy
2461 = 3: keep even if unsafe-to-copy
2462 */
2463 extern PNG_EXPORT(void, png_set_keep_unknown_chunks) PNGARG((png_structp
2464 png_ptr, int keep, png_bytep chunk_list, int num_chunks));
2465 extern PNG_EXPORT(void, png_set_unknown_chunks) PNGARG((png_structp png_ptr,
2466 png_infop info_ptr, png_unknown_chunkp unknowns, int num_unknowns));
2467 extern PNG_EXPORT(void, png_set_unknown_chunk_location)
2468 PNGARG((png_structp png_ptr, png_infop info_ptr, int chunk, int location));
2469 extern PNG_EXPORT(png_uint_32,png_get_unknown_chunks) PNGARG((png_structp
2470 png_ptr, png_infop info_ptr, png_unknown_chunkpp entries));
2471 #endif
2472 #ifdef PNG_HANDLE_AS_UNKNOWN_SUPPORTED
2473 PNG_EXPORT(int,png_handle_as_unknown) PNGARG((png_structp png_ptr, png_bytep
2474 chunk_name));
2475 #endif
2476
2477 /* Png_free_data() will turn off the "valid" flag for anything it frees.
2478 If you need to turn it off for a chunk that your application has freed,
2479 you can use png_set_invalid(png_ptr, info_ptr, PNG_INFO_CHNK); */
2480 extern PNG_EXPORT(void, png_set_invalid) PNGARG((png_structp png_ptr,
2481 png_infop info_ptr, int mask));
2482
2483 #if defined(PNG_INFO_IMAGE_SUPPORTED)
2484 /* The "params" pointer is currently not used and is for future expansion. */
2485 extern PNG_EXPORT(void, png_read_png) PNGARG((png_structp png_ptr,
2486 png_infop info_ptr,
2487 int transforms,
2488 png_voidp params));
2489 extern PNG_EXPORT(void, png_write_png) PNGARG((png_structp png_ptr,
2490 png_infop info_ptr,
2491 int transforms,
2492 png_voidp params));
2493 #endif
2494
2495 /* Define PNG_DEBUG at compile time for debugging information. Higher
2496 * numbers for PNG_DEBUG mean more debugging information. This has
2497 * only been added since version 0.95 so it is not implemented throughout
2498 * libpng yet, but more support will be added as needed.
2499 */
2500 #ifdef PNG_DEBUG
2501 #if (PNG_DEBUG > 0)
2502 #if !defined(PNG_DEBUG_FILE) && defined(_MSC_VER)
2503 #include <crtdbg.h>
2504 #if (PNG_DEBUG > 1)
2505 #define png_debug(l,m) _RPT0(_CRT_WARN,m)
2506 #define png_debug1(l,m,p1) _RPT1(_CRT_WARN,m,p1)
2507 #define png_debug2(l,m,p1,p2) _RPT2(_CRT_WARN,m,p1,p2)
2508 #endif
2509 #else /* PNG_DEBUG_FILE || !_MSC_VER */
2510 #ifndef PNG_DEBUG_FILE
2511 #define PNG_DEBUG_FILE stderr
2512 #endif /* PNG_DEBUG_FILE */
2513 #if (PNG_DEBUG > 1)
2514 #define png_debug(l,m) \
2515 { \
2516 int num_tabs=l; \
2517 fprintf(PNG_DEBUG_FILE,"%s"m,(num_tabs==1 ? "\t" : \
2518 (num_tabs==2 ? "\t\t":(num_tabs>2 ? "\t\t\t":"")))); \
2519 }
2520 #define png_debug1(l,m,p1) \
2521 { \
2522 int num_tabs=l; \
2523 fprintf(PNG_DEBUG_FILE,"%s"m,(num_tabs==1 ? "\t" : \
2524 (num_tabs==2 ? "\t\t":(num_tabs>2 ? "\t\t\t":""))),p1); \
2525 }
2526 #define png_debug2(l,m,p1,p2) \
2527 { \
2528 int num_tabs=l; \
2529 fprintf(PNG_DEBUG_FILE,"%s"m,(num_tabs==1 ? "\t" : \
2530 (num_tabs==2 ? "\t\t":(num_tabs>2 ? "\t\t\t":""))),p1,p2); \
2531 }
2532 #endif /* (PNG_DEBUG > 1) */
2533 #endif /* _MSC_VER */
2534 #endif /* (PNG_DEBUG > 0) */
2535 #endif /* PNG_DEBUG */
2536 #ifndef png_debug
2537 #define png_debug(l, m)
2538 #endif
2539 #ifndef png_debug1
2540 #define png_debug1(l, m, p1)
2541 #endif
2542 #ifndef png_debug2
2543 #define png_debug2(l, m, p1, p2)
2544 #endif
2545
2546 extern PNG_EXPORT(png_charp,png_get_copyright) PNGARG((png_structp png_ptr));
2547 extern PNG_EXPORT(png_charp,png_get_header_ver) PNGARG((png_structp png_ptr));
2548 extern PNG_EXPORT(png_charp,png_get_header_version) PNGARG((png_structp png_ptr));
2549 extern PNG_EXPORT(png_charp,png_get_libpng_ver) PNGARG((png_structp png_ptr));
2550
2551 #ifdef PNG_MNG_FEATURES_SUPPORTED
2552 extern PNG_EXPORT(png_uint_32,png_permit_mng_features) PNGARG((png_structp
2553 png_ptr, png_uint_32 mng_features_permitted));
2554 #endif
2555
2556 /* For use in png_set_keep_unknown, added to version 1.2.6 */
2557 #define PNG_HANDLE_CHUNK_AS_DEFAULT 0
2558 #define PNG_HANDLE_CHUNK_NEVER 1
2559 #define PNG_HANDLE_CHUNK_IF_SAFE 2
2560 #define PNG_HANDLE_CHUNK_ALWAYS 3
2561
2562 /* Added to version 1.2.0 */
2563 #if defined(PNG_ASSEMBLER_CODE_SUPPORTED)
2564 #if defined(PNG_MMX_CODE_SUPPORTED)
2565 #define PNG_ASM_FLAG_MMX_SUPPORT_COMPILED 0x01 /* not user-settable */
2566 #define PNG_ASM_FLAG_MMX_SUPPORT_IN_CPU 0x02 /* not user-settable */
2567 #define PNG_ASM_FLAG_MMX_READ_COMBINE_ROW 0x04
2568 #define PNG_ASM_FLAG_MMX_READ_INTERLACE 0x08
2569 #define PNG_ASM_FLAG_MMX_READ_FILTER_SUB 0x10
2570 #define PNG_ASM_FLAG_MMX_READ_FILTER_UP 0x20
2571 #define PNG_ASM_FLAG_MMX_READ_FILTER_AVG 0x40
2572 #define PNG_ASM_FLAG_MMX_READ_FILTER_PAETH 0x80
2573 #define PNG_ASM_FLAGS_INITIALIZED 0x80000000 /* not user-settable */
2574
2575 #define PNG_MMX_READ_FLAGS ( PNG_ASM_FLAG_MMX_READ_COMBINE_ROW \
2576 | PNG_ASM_FLAG_MMX_READ_INTERLACE \
2577 | PNG_ASM_FLAG_MMX_READ_FILTER_SUB \
2578 | PNG_ASM_FLAG_MMX_READ_FILTER_UP \
2579 | PNG_ASM_FLAG_MMX_READ_FILTER_AVG \
2580 | PNG_ASM_FLAG_MMX_READ_FILTER_PAETH )
2581 #define PNG_MMX_WRITE_FLAGS ( 0 )
2582
2583 #define PNG_MMX_FLAGS ( PNG_ASM_FLAG_MMX_SUPPORT_COMPILED \
2584 | PNG_ASM_FLAG_MMX_SUPPORT_IN_CPU \
2585 | PNG_MMX_READ_FLAGS \
2586 | PNG_MMX_WRITE_FLAGS )
2587
2588 #define PNG_SELECT_READ 1
2589 #define PNG_SELECT_WRITE 2
2590 #endif /* PNG_MMX_CODE_SUPPORTED */
2591
2592 #if !defined(PNG_1_0_X)
2593 /* pngget.c */
2594 extern PNG_EXPORT(png_uint_32,png_get_mmx_flagmask)
2595 PNGARG((int flag_select, int *compilerID));
2596
2597 /* pngget.c */
2598 extern PNG_EXPORT(png_uint_32,png_get_asm_flagmask)
2599 PNGARG((int flag_select));
2600
2601 /* pngget.c */
2602 extern PNG_EXPORT(png_uint_32,png_get_asm_flags)
2603 PNGARG((png_structp png_ptr));
2604
2605 /* pngget.c */
2606 extern PNG_EXPORT(png_byte,png_get_mmx_bitdepth_threshold)
2607 PNGARG((png_structp png_ptr));
2608
2609 /* pngget.c */
2610 extern PNG_EXPORT(png_uint_32,png_get_mmx_rowbytes_threshold)
2611 PNGARG((png_structp png_ptr));
2612
2613 /* pngset.c */
2614 extern PNG_EXPORT(void,png_set_asm_flags)
2615 PNGARG((png_structp png_ptr, png_uint_32 asm_flags));
2616
2617 /* pngset.c */
2618 extern PNG_EXPORT(void,png_set_mmx_thresholds)
2619 PNGARG((png_structp png_ptr, png_byte mmx_bitdepth_threshold,
2620 png_uint_32 mmx_rowbytes_threshold));
2621
2622 #endif /* PNG_1_0_X */
2623
2624 #if !defined(PNG_1_0_X)
2625 /* png.c, pnggccrd.c, or pngvcrd.c */
2626 extern PNG_EXPORT(int,png_mmx_support) PNGARG((void));
2627 #endif /* PNG_ASSEMBLER_CODE_SUPPORTED */
2628
2629 /* Strip the prepended error numbers ("#nnn ") from error and warning
2630 * messages before passing them to the error or warning handler. */
2631 #ifdef PNG_ERROR_NUMBERS_SUPPORTED
2632 extern PNG_EXPORT(void,png_set_strip_error_numbers) PNGARG((png_structp
2633 png_ptr, png_uint_32 strip_mode));
2634 #endif
2635
2636 #endif /* PNG_1_0_X */
2637
2638 /* Added at libpng-1.2.6 */
2639 #ifdef PNG_SET_USER_LIMITS_SUPPORTED
2640 extern PNG_EXPORT(void,png_set_user_limits) PNGARG((png_structp
2641 png_ptr, png_uint_32 user_width_max, png_uint_32 user_height_max));
2642 extern PNG_EXPORT(png_uint_32,png_get_user_width_max) PNGARG((png_structp
2643 png_ptr));
2644 extern PNG_EXPORT(png_uint_32,png_get_user_height_max) PNGARG((png_structp
2645 png_ptr));
2646 #endif
2647
2648 /* Maintainer: Put new public prototypes here ^, in libpng.3, and project defs */
2649
2650 #ifdef PNG_READ_COMPOSITE_NODIV_SUPPORTED
2651 /* With these routines we avoid an integer divide, which will be slower on
2652 * most machines. However, it does take more operations than the corresponding
2653 * divide method, so it may be slower on a few RISC systems. There are two
2654 * shifts (by 8 or 16 bits) and an addition, versus a single integer divide.
2655 *
2656 * Note that the rounding factors are NOT supposed to be the same! 128 and
2657 * 32768 are correct for the NODIV code; 127 and 32767 are correct for the
2658 * standard method.
2659 *
2660 * [Optimized code by Greg Roelofs and Mark Adler...blame us for bugs. :-) ]
2661 */
2662
2663 /* fg and bg should be in `gamma 1.0' space; alpha is the opacity */
2664
2665 # define png_composite(composite, fg, alpha, bg) \
2666 { png_uint_16 temp = (png_uint_16)((png_uint_16)(fg) * (png_uint_16)(alpha) \
2667 + (png_uint_16)(bg)*(png_uint_16)(255 - \
2668 (png_uint_16)(alpha)) + (png_uint_16)128); \
2669 (composite) = (png_byte)((temp + (temp >> 8)) >> 8); }
2670
2671 # define png_composite_16(composite, fg, alpha, bg) \
2672 { png_uint_32 temp = (png_uint_32)((png_uint_32)(fg) * (png_uint_32)(alpha) \
2673 + (png_uint_32)(bg)*(png_uint_32)(65535L - \
2674 (png_uint_32)(alpha)) + (png_uint_32)32768L); \
2675 (composite) = (png_uint_16)((temp + (temp >> 16)) >> 16); }
2676
2677 #else /* standard method using integer division */
2678
2679 # define png_composite(composite, fg, alpha, bg) \
2680 (composite) = (png_byte)(((png_uint_16)(fg) * (png_uint_16)(alpha) + \
2681 (png_uint_16)(bg) * (png_uint_16)(255 - (png_uint_16)(alpha)) + \
2682 (png_uint_16)127) / 255)
2683
2684 # define png_composite_16(composite, fg, alpha, bg) \
2685 (composite) = (png_uint_16)(((png_uint_32)(fg) * (png_uint_32)(alpha) + \
2686 (png_uint_32)(bg)*(png_uint_32)(65535L - (png_uint_32)(alpha)) + \
2687 (png_uint_32)32767) / (png_uint_32)65535L)
2688
2689 #endif /* PNG_READ_COMPOSITE_NODIV_SUPPORTED */
2690
2691 /* Inline macros to do direct reads of bytes from the input buffer. These
2692 * require that you are using an architecture that uses PNG byte ordering
2693 * (MSB first) and supports unaligned data storage. I think that PowerPC
2694 * in big-endian mode and 680x0 are the only ones that will support this.
2695 * The x86 line of processors definitely do not. The png_get_int_32()
2696 * routine also assumes we are using two's complement format for negative
2697 * values, which is almost certainly true.
2698 */
2699 #if defined(PNG_READ_BIG_ENDIAN_SUPPORTED)
2700 # define png_get_uint_32(buf) ( *((png_uint_32p) (buf)))
2701 # define png_get_uint_16(buf) ( *((png_uint_16p) (buf)))
2702 # define png_get_int_32(buf) ( *((png_int_32p) (buf)))
2703 #else
2704 extern PNG_EXPORT(png_uint_32,png_get_uint_32) PNGARG((png_bytep buf));
2705 extern PNG_EXPORT(png_uint_16,png_get_uint_16) PNGARG((png_bytep buf));
2706 extern PNG_EXPORT(png_int_32,png_get_int_32) PNGARG((png_bytep buf));
2707 #endif /* !PNG_READ_BIG_ENDIAN_SUPPORTED */
2708 extern PNG_EXPORT(png_uint_32,png_get_uint_31)
2709 PNGARG((png_structp png_ptr, png_bytep buf));
2710 /* No png_get_int_16 -- may be added if there's a real need for it. */
2711
2712 /* Place a 32-bit number into a buffer in PNG byte order (big-endian).
2713 */
2714 extern PNG_EXPORT(void,png_save_uint_32)
2715 PNGARG((png_bytep buf, png_uint_32 i));
2716 extern PNG_EXPORT(void,png_save_int_32)
2717 PNGARG((png_bytep buf, png_int_32 i));
2718
2719 /* Place a 16-bit number into a buffer in PNG byte order.
2720 * The parameter is declared unsigned int, not png_uint_16,
2721 * just to avoid potential problems on pre-ANSI C compilers.
2722 */
2723 extern PNG_EXPORT(void,png_save_uint_16)
2724 PNGARG((png_bytep buf, unsigned int i));
2725 /* No png_save_int_16 -- may be added if there's a real need for it. */
2726
2727 /* ************************************************************************* */
2728
2729 /* These next functions are used internally in the code. They generally
2730 * shouldn't be used unless you are writing code to add or replace some
2731 * functionality in libpng. More information about most functions can
2732 * be found in the files where the functions are located.
2733 */
2734
2735
2736 /* Various modes of operation, that are visible to applications because
2737 * they are used for unknown chunk location.
2738 */
2739 #define PNG_HAVE_IHDR 0x01
2740 #define PNG_HAVE_PLTE 0x02
2741 #define PNG_HAVE_IDAT 0x04
2742 #define PNG_AFTER_IDAT 0x08 /* Have complete zlib datastream */
2743 #define PNG_HAVE_IEND 0x10
2744
2745 #if defined(PNG_INTERNAL)
2746
2747 /* More modes of operation. Note that after an init, mode is set to
2748 * zero automatically when the structure is created.
2749 */
2750 #define PNG_HAVE_gAMA 0x20
2751 #define PNG_HAVE_cHRM 0x40
2752 #define PNG_HAVE_sRGB 0x80
2753 #define PNG_HAVE_CHUNK_HEADER 0x100
2754 #define PNG_WROTE_tIME 0x200
2755 #define PNG_WROTE_INFO_BEFORE_PLTE 0x400
2756 #define PNG_BACKGROUND_IS_GRAY 0x800
2757 #define PNG_HAVE_PNG_SIGNATURE 0x1000
2758 #define PNG_HAVE_CHUNK_AFTER_IDAT 0x2000 /* Have another chunk after IDAT */
2759
2760 /* flags for the transformations the PNG library does on the image data */
2761 #define PNG_BGR 0x0001
2762 #define PNG_INTERLACE 0x0002
2763 #define PNG_PACK 0x0004
2764 #define PNG_SHIFT 0x0008
2765 #define PNG_SWAP_BYTES 0x0010
2766 #define PNG_INVERT_MONO 0x0020
2767 #define PNG_DITHER 0x0040
2768 #define PNG_BACKGROUND 0x0080
2769 #define PNG_BACKGROUND_EXPAND 0x0100
2770 /* 0x0200 unused */
2771 #define PNG_16_TO_8 0x0400
2772 #define PNG_RGBA 0x0800
2773 #define PNG_EXPAND 0x1000
2774 #define PNG_GAMMA 0x2000
2775 #define PNG_GRAY_TO_RGB 0x4000
2776 #define PNG_FILLER 0x8000L
2777 #define PNG_PACKSWAP 0x10000L
2778 #define PNG_SWAP_ALPHA 0x20000L
2779 #define PNG_STRIP_ALPHA 0x40000L
2780 #define PNG_INVERT_ALPHA 0x80000L
2781 #define PNG_USER_TRANSFORM 0x100000L
2782 #define PNG_RGB_TO_GRAY_ERR 0x200000L
2783 #define PNG_RGB_TO_GRAY_WARN 0x400000L
2784 #define PNG_RGB_TO_GRAY 0x600000L /* two bits, RGB_TO_GRAY_ERR|WARN */
2785 /* 0x800000L Unused */
2786 #define PNG_ADD_ALPHA 0x1000000L /* Added to libpng-1.2.7 */
2787 #define PNG_EXPAND_tRNS 0x2000000L /* Added to libpng-1.2.9 */
2788 /* 0x4000000L unused */
2789 /* 0x8000000L unused */
2790 /* 0x10000000L unused */
2791 /* 0x20000000L unused */
2792 /* 0x40000000L unused */
2793
2794 /* flags for png_create_struct */
2795 #define PNG_STRUCT_PNG 0x0001
2796 #define PNG_STRUCT_INFO 0x0002
2797
2798 /* Scaling factor for filter heuristic weighting calculations */
2799 #define PNG_WEIGHT_SHIFT 8
2800 #define PNG_WEIGHT_FACTOR (1<<(PNG_WEIGHT_SHIFT))
2801 #define PNG_COST_SHIFT 3
2802 #define PNG_COST_FACTOR (1<<(PNG_COST_SHIFT))
2803
2804 /* flags for the png_ptr->flags rather than declaring a byte for each one */
2805 #define PNG_FLAG_ZLIB_CUSTOM_STRATEGY 0x0001
2806 #define PNG_FLAG_ZLIB_CUSTOM_LEVEL 0x0002
2807 #define PNG_FLAG_ZLIB_CUSTOM_MEM_LEVEL 0x0004
2808 #define PNG_FLAG_ZLIB_CUSTOM_WINDOW_BITS 0x0008
2809 #define PNG_FLAG_ZLIB_CUSTOM_METHOD 0x0010
2810 #define PNG_FLAG_ZLIB_FINISHED 0x0020
2811 #define PNG_FLAG_ROW_INIT 0x0040
2812 #define PNG_FLAG_FILLER_AFTER 0x0080
2813 #define PNG_FLAG_CRC_ANCILLARY_USE 0x0100
2814 #define PNG_FLAG_CRC_ANCILLARY_NOWARN 0x0200
2815 #define PNG_FLAG_CRC_CRITICAL_USE 0x0400
2816 #define PNG_FLAG_CRC_CRITICAL_IGNORE 0x0800
2817 #define PNG_FLAG_FREE_PLTE 0x1000
2818 #define PNG_FLAG_FREE_TRNS 0x2000
2819 #define PNG_FLAG_FREE_HIST 0x4000
2820 #define PNG_FLAG_KEEP_UNKNOWN_CHUNKS 0x8000L
2821 #define PNG_FLAG_KEEP_UNSAFE_CHUNKS 0x10000L
2822 #define PNG_FLAG_LIBRARY_MISMATCH 0x20000L
2823 #define PNG_FLAG_STRIP_ERROR_NUMBERS 0x40000L
2824 #define PNG_FLAG_STRIP_ERROR_TEXT 0x80000L
2825 #define PNG_FLAG_MALLOC_NULL_MEM_OK 0x100000L
2826 #define PNG_FLAG_ADD_ALPHA 0x200000L /* Added to libpng-1.2.8 */
2827 #define PNG_FLAG_STRIP_ALPHA 0x400000L /* Added to libpng-1.2.8 */
2828 /* 0x800000L unused */
2829 /* 0x1000000L unused */
2830 /* 0x2000000L unused */
2831 /* 0x4000000L unused */
2832 /* 0x8000000L unused */
2833 /* 0x10000000L unused */
2834 /* 0x20000000L unused */
2835 /* 0x40000000L unused */
2836
2837 #define PNG_FLAG_CRC_ANCILLARY_MASK (PNG_FLAG_CRC_ANCILLARY_USE | \
2838 PNG_FLAG_CRC_ANCILLARY_NOWARN)
2839
2840 #define PNG_FLAG_CRC_CRITICAL_MASK (PNG_FLAG_CRC_CRITICAL_USE | \
2841 PNG_FLAG_CRC_CRITICAL_IGNORE)
2842
2843 #define PNG_FLAG_CRC_MASK (PNG_FLAG_CRC_ANCILLARY_MASK | \
2844 PNG_FLAG_CRC_CRITICAL_MASK)
2845
2846 /* save typing and make code easier to understand */
2847
2848 #define PNG_COLOR_DIST(c1, c2) (abs((int)((c1).red) - (int)((c2).red)) + \
2849 abs((int)((c1).green) - (int)((c2).green)) + \
2850 abs((int)((c1).blue) - (int)((c2).blue)))
2851
2852 /* Added to libpng-1.2.6 JB */
2853 #define PNG_ROWBYTES(pixel_bits, width) \
2854 ((pixel_bits) >= 8 ? \
2855 ((width) * (((png_uint_32)(pixel_bits)) >> 3)) : \
2856 (( ((width) * ((png_uint_32)(pixel_bits))) + 7) >> 3) )
2857
2858 /* PNG_OUT_OF_RANGE returns true if value is outside the range
2859 ideal-delta..ideal+delta. Each argument is evaluated twice.
2860 "ideal" and "delta" should be constants, normally simple
2861 integers, "value" a variable. Added to libpng-1.2.6 JB */
2862 #define PNG_OUT_OF_RANGE(value, ideal, delta) \
2863 ( (value) < (ideal)-(delta) || (value) > (ideal)+(delta) )
2864
2865 /* variables declared in png.c - only it needs to define PNG_NO_EXTERN */
2866 #if !defined(PNG_NO_EXTERN) || defined(PNG_ALWAYS_EXTERN)
2867 /* place to hold the signature string for a PNG file. */
2868 #ifdef PNG_USE_GLOBAL_ARRAYS
2869 PNG_EXPORT_VAR (PNG_CONST png_byte FARDATA) png_sig[8];
2870 #else
2871 #endif
2872 #endif /* PNG_NO_EXTERN */
2873
2874 /* Constant strings for known chunk types. If you need to add a chunk,
2875 * define the name here, and add an invocation of the macro in png.c and
2876 * wherever it's needed.
2877 */
2878 #define PNG_IHDR png_byte png_IHDR[5] = { 73, 72, 68, 82, '\0'}
2879 #define PNG_IDAT png_byte png_IDAT[5] = { 73, 68, 65, 84, '\0'}
2880 #define PNG_IEND png_byte png_IEND[5] = { 73, 69, 78, 68, '\0'}
2881 #define PNG_PLTE png_byte png_PLTE[5] = { 80, 76, 84, 69, '\0'}
2882 #define PNG_bKGD png_byte png_bKGD[5] = { 98, 75, 71, 68, '\0'}
2883 #define PNG_cHRM png_byte png_cHRM[5] = { 99, 72, 82, 77, '\0'}
2884 #define PNG_gAMA png_byte png_gAMA[5] = {103, 65, 77, 65, '\0'}
2885 #define PNG_hIST png_byte png_hIST[5] = {104, 73, 83, 84, '\0'}
2886 #define PNG_iCCP png_byte png_iCCP[5] = {105, 67, 67, 80, '\0'}
2887 #define PNG_iTXt png_byte png_iTXt[5] = {105, 84, 88, 116, '\0'}
2888 #define PNG_oFFs png_byte png_oFFs[5] = {111, 70, 70, 115, '\0'}
2889 #define PNG_pCAL png_byte png_pCAL[5] = {112, 67, 65, 76, '\0'}
2890 #define PNG_sCAL png_byte png_sCAL[5] = {115, 67, 65, 76, '\0'}
2891 #define PNG_pHYs png_byte png_pHYs[5] = {112, 72, 89, 115, '\0'}
2892 #define PNG_sBIT png_byte png_sBIT[5] = {115, 66, 73, 84, '\0'}
2893 #define PNG_sPLT png_byte png_sPLT[5] = {115, 80, 76, 84, '\0'}
2894 #define PNG_sRGB png_byte png_sRGB[5] = {115, 82, 71, 66, '\0'}
2895 #define PNG_tEXt png_byte png_tEXt[5] = {116, 69, 88, 116, '\0'}
2896 #define PNG_tIME png_byte png_tIME[5] = {116, 73, 77, 69, '\0'}
2897 #define PNG_tRNS png_byte png_tRNS[5] = {116, 82, 78, 83, '\0'}
2898 #define PNG_zTXt png_byte png_zTXt[5] = {122, 84, 88, 116, '\0'}
2899
2900 #ifdef PNG_USE_GLOBAL_ARRAYS
2901 PNG_EXPORT_VAR (png_byte FARDATA) png_IHDR[5];
2902 PNG_EXPORT_VAR (png_byte FARDATA) png_IDAT[5];
2903 PNG_EXPORT_VAR (png_byte FARDATA) png_IEND[5];
2904 PNG_EXPORT_VAR (png_byte FARDATA) png_PLTE[5];
2905 PNG_EXPORT_VAR (png_byte FARDATA) png_bKGD[5];
2906 PNG_EXPORT_VAR (png_byte FARDATA) png_cHRM[5];
2907 PNG_EXPORT_VAR (png_byte FARDATA) png_gAMA[5];
2908 PNG_EXPORT_VAR (png_byte FARDATA) png_hIST[5];
2909 PNG_EXPORT_VAR (png_byte FARDATA) png_iCCP[5];
2910 PNG_EXPORT_VAR (png_byte FARDATA) png_iTXt[5];
2911 PNG_EXPORT_VAR (png_byte FARDATA) png_oFFs[5];
2912 PNG_EXPORT_VAR (png_byte FARDATA) png_pCAL[5];
2913 PNG_EXPORT_VAR (png_byte FARDATA) png_sCAL[5];
2914 PNG_EXPORT_VAR (png_byte FARDATA) png_pHYs[5];
2915 PNG_EXPORT_VAR (png_byte FARDATA) png_sBIT[5];
2916 PNG_EXPORT_VAR (png_byte FARDATA) png_sPLT[5];
2917 PNG_EXPORT_VAR (png_byte FARDATA) png_sRGB[5];
2918 PNG_EXPORT_VAR (png_byte FARDATA) png_tEXt[5];
2919 PNG_EXPORT_VAR (png_byte FARDATA) png_tIME[5];
2920 PNG_EXPORT_VAR (png_byte FARDATA) png_tRNS[5];
2921 PNG_EXPORT_VAR (png_byte FARDATA) png_zTXt[5];
2922 #endif /* PNG_USE_GLOBAL_ARRAYS */
2923
2924 #if defined(PNG_1_0_X) || defined (PNG_1_2_X)
2925 /* Initialize png_ptr struct for reading, and allocate any other memory.
2926 * (old interface - DEPRECATED - use png_create_read_struct instead).
2927 */
2928 extern PNG_EXPORT(void,png_read_init) PNGARG((png_structp png_ptr));
2929 #undef png_read_init
2930 #define png_read_init(png_ptr) png_read_init_3(&png_ptr, \
2931 PNG_LIBPNG_VER_STRING, png_sizeof(png_struct));
2932 #endif
2933
2934 extern PNG_EXPORT(void,png_read_init_3) PNGARG((png_structpp ptr_ptr,
2935 png_const_charp user_png_ver, png_size_t png_struct_size));
2936 #if defined(PNG_1_0_X) || defined (PNG_1_2_X)
2937 extern PNG_EXPORT(void,png_read_init_2) PNGARG((png_structp png_ptr,
2938 png_const_charp user_png_ver, png_size_t png_struct_size, png_size_t
2939 png_info_size));
2940 #endif
2941
2942 #if defined(PNG_1_0_X) || defined (PNG_1_2_X)
2943 /* Initialize png_ptr struct for writing, and allocate any other memory.
2944 * (old interface - DEPRECATED - use png_create_write_struct instead).
2945 */
2946 extern PNG_EXPORT(void,png_write_init) PNGARG((png_structp png_ptr));
2947 #undef png_write_init
2948 #define png_write_init(png_ptr) png_write_init_3(&png_ptr, \
2949 PNG_LIBPNG_VER_STRING, png_sizeof(png_struct));
2950 #endif
2951
2952 extern PNG_EXPORT(void,png_write_init_3) PNGARG((png_structpp ptr_ptr,
2953 png_const_charp user_png_ver, png_size_t png_struct_size));
2954 extern PNG_EXPORT(void,png_write_init_2) PNGARG((png_structp png_ptr,
2955 png_const_charp user_png_ver, png_size_t png_struct_size, png_size_t
2956 png_info_size));
2957
2958 /* Allocate memory for an internal libpng struct */
2959 PNG_EXTERN png_voidp png_create_struct PNGARG((int type));
2960
2961 /* Free memory from internal libpng struct */
2962 PNG_EXTERN void png_destroy_struct PNGARG((png_voidp struct_ptr));
2963
2964 PNG_EXTERN png_voidp png_create_struct_2 PNGARG((int type, png_malloc_ptr
2965 malloc_fn, png_voidp mem_ptr));
2966 PNG_EXTERN void png_destroy_struct_2 PNGARG((png_voidp struct_ptr,
2967 png_free_ptr free_fn, png_voidp mem_ptr));
2968
2969 /* Free any memory that info_ptr points to and reset struct. */
2970 PNG_EXTERN void png_info_destroy PNGARG((png_structp png_ptr,
2971 png_infop info_ptr));
2972
2973 #ifndef PNG_1_0_X
2974 /* Function to allocate memory for zlib. */
2975 PNG_EXTERN voidpf png_zalloc PNGARG((voidpf png_ptr, uInt items, uInt size));
2976
2977 /* Function to free memory for zlib */
2978 PNG_EXTERN void png_zfree PNGARG((voidpf png_ptr, voidpf ptr));
2979
2980 #ifdef PNG_SIZE_T
2981 /* Function to convert a sizeof an item to png_sizeof item */
2982 PNG_EXTERN png_size_t PNGAPI png_convert_size PNGARG((size_t size));
2983 #endif
2984
2985 /* Next four functions are used internally as callbacks. PNGAPI is required
2986 * but not PNG_EXPORT. PNGAPI added at libpng version 1.2.3. */
2987
2988 PNG_EXTERN void PNGAPI png_default_read_data PNGARG((png_structp png_ptr,
2989 png_bytep data, png_size_t length));
2990
2991 #ifdef PNG_PROGRESSIVE_READ_SUPPORTED
2992 PNG_EXTERN void PNGAPI png_push_fill_buffer PNGARG((png_structp png_ptr,
2993 png_bytep buffer, png_size_t length));
2994 #endif
2995
2996 PNG_EXTERN void PNGAPI png_default_write_data PNGARG((png_structp png_ptr,
2997 png_bytep data, png_size_t length));
2998
2999 #if defined(PNG_WRITE_FLUSH_SUPPORTED)
3000 #if !defined(PNG_NO_STDIO)
3001 PNG_EXTERN void PNGAPI png_default_flush PNGARG((png_structp png_ptr));
3002 #endif
3003 #endif
3004 #else /* PNG_1_0_X */
3005 #ifdef PNG_PROGRESSIVE_READ_SUPPORTED
3006 PNG_EXTERN void png_push_fill_buffer PNGARG((png_structp png_ptr,
3007 png_bytep buffer, png_size_t length));
3008 #endif
3009 #endif /* PNG_1_0_X */
3010
3011 /* Reset the CRC variable */
3012 PNG_EXTERN void png_reset_crc PNGARG((png_structp png_ptr));
3013
3014 /* Write the "data" buffer to whatever output you are using. */
3015 PNG_EXTERN void png_write_data PNGARG((png_structp png_ptr, png_bytep data,
3016 png_size_t length));
3017
3018 /* Read data from whatever input you are using into the "data" buffer */
3019 PNG_EXTERN void png_read_data PNGARG((png_structp png_ptr, png_bytep data,
3020 png_size_t length));
3021
3022 /* Read bytes into buf, and update png_ptr->crc */
3023 PNG_EXTERN void png_crc_read PNGARG((png_structp png_ptr, png_bytep buf,
3024 png_size_t length));
3025
3026 /* Decompress data in a chunk that uses compression */
3027 #if defined(PNG_zTXt_SUPPORTED) || defined(PNG_iTXt_SUPPORTED) || \
3028 defined(PNG_iCCP_SUPPORTED) || defined(PNG_sPLT_SUPPORTED)
3029 PNG_EXTERN png_charp png_decompress_chunk PNGARG((png_structp png_ptr,
3030 int comp_type, png_charp chunkdata, png_size_t chunklength,
3031 png_size_t prefix_length, png_size_t *data_length));
3032 #endif
3033
3034 /* Read "skip" bytes, read the file crc, and (optionally) verify png_ptr->crc */
3035 PNG_EXTERN int png_crc_finish PNGARG((png_structp png_ptr, png_uint_32 skip));
3036
3037 /* Read the CRC from the file and compare it to the libpng calculated CRC */
3038 PNG_EXTERN int png_crc_error PNGARG((png_structp png_ptr));
3039
3040 /* Calculate the CRC over a section of data. Note that we are only
3041 * passing a maximum of 64K on systems that have this as a memory limit,
3042 * since this is the maximum buffer size we can specify.
3043 */
3044 PNG_EXTERN void png_calculate_crc PNGARG((png_structp png_ptr, png_bytep ptr,
3045 png_size_t length));
3046
3047 #if defined(PNG_WRITE_FLUSH_SUPPORTED)
3048 PNG_EXTERN void png_flush PNGARG((png_structp png_ptr));
3049 #endif
3050
3051 /* simple function to write the signature */
3052 PNG_EXTERN void png_write_sig PNGARG((png_structp png_ptr));
3053
3054 /* write various chunks */
3055
3056 /* Write the IHDR chunk, and update the png_struct with the necessary
3057 * information.
3058 */
3059 PNG_EXTERN void png_write_IHDR PNGARG((png_structp png_ptr, png_uint_32 width,
3060 png_uint_32 height,
3061 int bit_depth, int color_type, int compression_method, int filter_method,
3062 int interlace_method));
3063
3064 PNG_EXTERN void png_write_PLTE PNGARG((png_structp png_ptr, png_colorp palette,
3065 png_uint_32 num_pal));
3066
3067 PNG_EXTERN void png_write_IDAT PNGARG((png_structp png_ptr, png_bytep data,
3068 png_size_t length));
3069
3070 PNG_EXTERN void png_write_IEND PNGARG((png_structp png_ptr));
3071
3072 #if defined(PNG_WRITE_gAMA_SUPPORTED)
3073 #ifdef PNG_FLOATING_POINT_SUPPORTED
3074 PNG_EXTERN void png_write_gAMA PNGARG((png_structp png_ptr, double file_gamma));
3075 #endif
3076 #ifdef PNG_FIXED_POINT_SUPPORTED
3077 PNG_EXTERN void png_write_gAMA_fixed PNGARG((png_structp png_ptr, png_fixed_point
3078 file_gamma));
3079 #endif
3080 #endif
3081
3082 #if defined(PNG_WRITE_sBIT_SUPPORTED)
3083 PNG_EXTERN void png_write_sBIT PNGARG((png_structp png_ptr, png_color_8p sbit,
3084 int color_type));
3085 #endif
3086
3087 #if defined(PNG_WRITE_cHRM_SUPPORTED)
3088 #ifdef PNG_FLOATING_POINT_SUPPORTED
3089 PNG_EXTERN void png_write_cHRM PNGARG((png_structp png_ptr,
3090 double white_x, double white_y,
3091 double red_x, double red_y, double green_x, double green_y,
3092 double blue_x, double blue_y));
3093 #endif
3094 #ifdef PNG_FIXED_POINT_SUPPORTED
3095 PNG_EXTERN void png_write_cHRM_fixed PNGARG((png_structp png_ptr,
3096 png_fixed_point int_white_x, png_fixed_point int_white_y,
3097 png_fixed_point int_red_x, png_fixed_point int_red_y, png_fixed_point
3098 int_green_x, png_fixed_point int_green_y, png_fixed_point int_blue_x,
3099 png_fixed_point int_blue_y));
3100 #endif
3101 #endif
3102
3103 #if defined(PNG_WRITE_sRGB_SUPPORTED)
3104 PNG_EXTERN void png_write_sRGB PNGARG((png_structp png_ptr,
3105 int intent));
3106 #endif
3107
3108 #if defined(PNG_WRITE_iCCP_SUPPORTED)
3109 PNG_EXTERN void png_write_iCCP PNGARG((png_structp png_ptr,
3110 png_charp name, int compression_type,
3111 png_charp profile, int proflen));
3112 /* Note to maintainer: profile should be png_bytep */
3113 #endif
3114
3115 #if defined(PNG_WRITE_sPLT_SUPPORTED)
3116 PNG_EXTERN void png_write_sPLT PNGARG((png_structp png_ptr,
3117 png_sPLT_tp palette));
3118 #endif
3119
3120 #if defined(PNG_WRITE_tRNS_SUPPORTED)
3121 PNG_EXTERN void png_write_tRNS PNGARG((png_structp png_ptr, png_bytep trans,
3122 png_color_16p values, int number, int color_type));
3123 #endif
3124
3125 #if defined(PNG_WRITE_bKGD_SUPPORTED)
3126 PNG_EXTERN void png_write_bKGD PNGARG((png_structp png_ptr,
3127 png_color_16p values, int color_type));
3128 #endif
3129
3130 #if defined(PNG_WRITE_hIST_SUPPORTED)
3131 PNG_EXTERN void png_write_hIST PNGARG((png_structp png_ptr, png_uint_16p hist,
3132 int num_hist));
3133 #endif
3134
3135 #if defined(PNG_WRITE_TEXT_SUPPORTED) || defined(PNG_WRITE_pCAL_SUPPORTED) || \
3136 defined(PNG_WRITE_iCCP_SUPPORTED) || defined(PNG_WRITE_sPLT_SUPPORTED)
3137 PNG_EXTERN png_size_t png_check_keyword PNGARG((png_structp png_ptr,
3138 png_charp key, png_charpp new_key));
3139 #endif
3140
3141 #if defined(PNG_WRITE_tEXt_SUPPORTED)
3142 PNG_EXTERN void png_write_tEXt PNGARG((png_structp png_ptr, png_charp key,
3143 png_charp text, png_size_t text_len));
3144 #endif
3145
3146 #if defined(PNG_WRITE_zTXt_SUPPORTED)
3147 PNG_EXTERN void png_write_zTXt PNGARG((png_structp png_ptr, png_charp key,
3148 png_charp text, png_size_t text_len, int compression));
3149 #endif
3150
3151 #if defined(PNG_WRITE_iTXt_SUPPORTED)
3152 PNG_EXTERN void png_write_iTXt PNGARG((png_structp png_ptr,
3153 int compression, png_charp key, png_charp lang, png_charp lang_key,
3154 png_charp text));
3155 #endif
3156
3157 #if defined(PNG_TEXT_SUPPORTED) /* Added at version 1.0.14 and 1.2.4 */
3158 PNG_EXTERN int png_set_text_2 PNGARG((png_structp png_ptr,
3159 png_infop info_ptr, png_textp text_ptr, int num_text));
3160 #endif
3161
3162 #if defined(PNG_WRITE_oFFs_SUPPORTED)
3163 PNG_EXTERN void png_write_oFFs PNGARG((png_structp png_ptr,
3164 png_int_32 x_offset, png_int_32 y_offset, int unit_type));
3165 #endif
3166
3167 #if defined(PNG_WRITE_pCAL_SUPPORTED)
3168 PNG_EXTERN void png_write_pCAL PNGARG((png_structp png_ptr, png_charp purpose,
3169 png_int_32 X0, png_int_32 X1, int type, int nparams,
3170 png_charp units, png_charpp params));
3171 #endif
3172
3173 #if defined(PNG_WRITE_pHYs_SUPPORTED)
3174 PNG_EXTERN void png_write_pHYs PNGARG((png_structp png_ptr,
3175 png_uint_32 x_pixels_per_unit, png_uint_32 y_pixels_per_unit,
3176 int unit_type));
3177 #endif
3178
3179 #if defined(PNG_WRITE_tIME_SUPPORTED)
3180 PNG_EXTERN void png_write_tIME PNGARG((png_structp png_ptr,
3181 png_timep mod_time));
3182 #endif
3183
3184 #if defined(PNG_WRITE_sCAL_SUPPORTED)
3185 #if defined(PNG_FLOATING_POINT_SUPPORTED) && !defined(PNG_NO_STDIO)
3186 PNG_EXTERN void png_write_sCAL PNGARG((png_structp png_ptr,
3187 int unit, double width, double height));
3188 #else
3189 #ifdef PNG_FIXED_POINT_SUPPORTED
3190 PNG_EXTERN void png_write_sCAL_s PNGARG((png_structp png_ptr,
3191 int unit, png_charp width, png_charp height));
3192 #endif
3193 #endif
3194 #endif
3195
3196 /* Called when finished processing a row of data */
3197 PNG_EXTERN void png_write_finish_row PNGARG((png_structp png_ptr));
3198
3199 /* Internal use only. Called before first row of data */
3200 PNG_EXTERN void png_write_start_row PNGARG((png_structp png_ptr));
3201
3202 #if defined(PNG_READ_GAMMA_SUPPORTED)
3203 PNG_EXTERN void png_build_gamma_table PNGARG((png_structp png_ptr));
3204 #endif
3205
3206 /* combine a row of data, dealing with alpha, etc. if requested */
3207 PNG_EXTERN void png_combine_row PNGARG((png_structp png_ptr, png_bytep row,
3208 int mask));
3209
3210 #if defined(PNG_READ_INTERLACING_SUPPORTED)
3211 /* expand an interlaced row */
3212 /* OLD pre-1.0.9 interface:
3213 PNG_EXTERN void png_do_read_interlace PNGARG((png_row_infop row_info,
3214 png_bytep row, int pass, png_uint_32 transformations));
3215 */
3216 PNG_EXTERN void png_do_read_interlace PNGARG((png_structp png_ptr));
3217 #endif
3218
3219 /* GRR TO DO (2.0 or whenever): simplify other internal calling interfaces */
3220
3221 #if defined(PNG_WRITE_INTERLACING_SUPPORTED)
3222 /* grab pixels out of a row for an interlaced pass */
3223 PNG_EXTERN void png_do_write_interlace PNGARG((png_row_infop row_info,
3224 png_bytep row, int pass));
3225 #endif
3226
3227 /* unfilter a row */
3228 PNG_EXTERN void png_read_filter_row PNGARG((png_structp png_ptr,
3229 png_row_infop row_info, png_bytep row, png_bytep prev_row, int filter));
3230
3231 /* Choose the best filter to use and filter the row data */
3232 PNG_EXTERN void png_write_find_filter PNGARG((png_structp png_ptr,
3233 png_row_infop row_info));
3234
3235 /* Write out the filtered row. */
3236 PNG_EXTERN void png_write_filtered_row PNGARG((png_structp png_ptr,
3237 png_bytep filtered_row));
3238 /* finish a row while reading, dealing with interlacing passes, etc. */
3239 PNG_EXTERN void png_read_finish_row PNGARG((png_structp png_ptr));
3240
3241 /* initialize the row buffers, etc. */
3242 PNG_EXTERN void png_read_start_row PNGARG((png_structp png_ptr));
3243 /* optional call to update the users info structure */
3244 PNG_EXTERN void png_read_transform_info PNGARG((png_structp png_ptr,
3245 png_infop info_ptr));
3246
3247 /* these are the functions that do the transformations */
3248 #if defined(PNG_READ_FILLER_SUPPORTED)
3249 PNG_EXTERN void png_do_read_filler PNGARG((png_row_infop row_info,
3250 png_bytep row, png_uint_32 filler, png_uint_32 flags));
3251 #endif
3252
3253 #if defined(PNG_READ_SWAP_ALPHA_SUPPORTED)
3254 PNG_EXTERN void png_do_read_swap_alpha PNGARG((png_row_infop row_info,
3255 png_bytep row));
3256 #endif
3257
3258 #if defined(PNG_WRITE_SWAP_ALPHA_SUPPORTED)
3259 PNG_EXTERN void png_do_write_swap_alpha PNGARG((png_row_infop row_info,
3260 png_bytep row));
3261 #endif
3262
3263 #if defined(PNG_READ_INVERT_ALPHA_SUPPORTED)
3264 PNG_EXTERN void png_do_read_invert_alpha PNGARG((png_row_infop row_info,
3265 png_bytep row));
3266 #endif
3267
3268 #if defined(PNG_WRITE_INVERT_ALPHA_SUPPORTED)
3269 PNG_EXTERN void png_do_write_invert_alpha PNGARG((png_row_infop row_info,
3270 png_bytep row));
3271 #endif
3272
3273 #if defined(PNG_WRITE_FILLER_SUPPORTED) || \
3274 defined(PNG_READ_STRIP_ALPHA_SUPPORTED)
3275 PNG_EXTERN void png_do_strip_filler PNGARG((png_row_infop row_info,
3276 png_bytep row, png_uint_32 flags));
3277 #endif
3278
3279 #if defined(PNG_READ_SWAP_SUPPORTED) || defined(PNG_WRITE_SWAP_SUPPORTED)
3280 PNG_EXTERN void png_do_swap PNGARG((png_row_infop row_info, png_bytep row));
3281 #endif
3282
3283 #if defined(PNG_READ_PACKSWAP_SUPPORTED) || defined(PNG_WRITE_PACKSWAP_SUPPORTED)
3284 PNG_EXTERN void png_do_packswap PNGARG((png_row_infop row_info, png_bytep row));
3285 #endif
3286
3287 #if defined(PNG_READ_RGB_TO_GRAY_SUPPORTED)
3288 PNG_EXTERN int png_do_rgb_to_gray PNGARG((png_structp png_ptr, png_row_infop
3289 row_info, png_bytep row));
3290 #endif
3291
3292 #if defined(PNG_READ_GRAY_TO_RGB_SUPPORTED)
3293 PNG_EXTERN void png_do_gray_to_rgb PNGARG((png_row_infop row_info,
3294 png_bytep row));
3295 #endif
3296
3297 #if defined(PNG_READ_PACK_SUPPORTED)
3298 PNG_EXTERN void png_do_unpack PNGARG((png_row_infop row_info, png_bytep row));
3299 #endif
3300
3301 #if defined(PNG_READ_SHIFT_SUPPORTED)
3302 PNG_EXTERN void png_do_unshift PNGARG((png_row_infop row_info, png_bytep row,
3303 png_color_8p sig_bits));
3304 #endif
3305
3306 #if defined(PNG_READ_INVERT_SUPPORTED) || defined(PNG_WRITE_INVERT_SUPPORTED)
3307 PNG_EXTERN void png_do_invert PNGARG((png_row_infop row_info, png_bytep row));
3308 #endif
3309
3310 #if defined(PNG_READ_16_TO_8_SUPPORTED)
3311 PNG_EXTERN void png_do_chop PNGARG((png_row_infop row_info, png_bytep row));
3312 #endif
3313
3314 #if defined(PNG_READ_DITHER_SUPPORTED)
3315 PNG_EXTERN void png_do_dither PNGARG((png_row_infop row_info,
3316 png_bytep row, png_bytep palette_lookup, png_bytep dither_lookup));
3317
3318 # if defined(PNG_CORRECT_PALETTE_SUPPORTED)
3319 PNG_EXTERN void png_correct_palette PNGARG((png_structp png_ptr,
3320 png_colorp palette, int num_palette));
3321 # endif
3322 #endif
3323
3324 #if defined(PNG_READ_BGR_SUPPORTED) || defined(PNG_WRITE_BGR_SUPPORTED)
3325 PNG_EXTERN void png_do_bgr PNGARG((png_row_infop row_info, png_bytep row));
3326 #endif
3327
3328 #if defined(PNG_WRITE_PACK_SUPPORTED)
3329 PNG_EXTERN void png_do_pack PNGARG((png_row_infop row_info,
3330 png_bytep row, png_uint_32 bit_depth));
3331 #endif
3332
3333 #if defined(PNG_WRITE_SHIFT_SUPPORTED)
3334 PNG_EXTERN void png_do_shift PNGARG((png_row_infop row_info, png_bytep row,
3335 png_color_8p bit_depth));
3336 #endif
3337
3338 #if defined(PNG_READ_BACKGROUND_SUPPORTED)
3339 #if defined(PNG_READ_GAMMA_SUPPORTED)
3340 PNG_EXTERN void png_do_background PNGARG((png_row_infop row_info, png_bytep row,
3341 png_color_16p trans_values, png_color_16p background,
3342 png_color_16p background_1,
3343 png_bytep gamma_table, png_bytep gamma_from_1, png_bytep gamma_to_1,
3344 png_uint_16pp gamma_16, png_uint_16pp gamma_16_from_1,
3345 png_uint_16pp gamma_16_to_1, int gamma_shift));
3346 #else
3347 PNG_EXTERN void png_do_background PNGARG((png_row_infop row_info, png_bytep row,
3348 png_color_16p trans_values, png_color_16p background));
3349 #endif
3350 #endif
3351
3352 #if defined(PNG_READ_GAMMA_SUPPORTED)
3353 PNG_EXTERN void png_do_gamma PNGARG((png_row_infop row_info, png_bytep row,
3354 png_bytep gamma_table, png_uint_16pp gamma_16_table,
3355 int gamma_shift));
3356 #endif
3357
3358 #if defined(PNG_READ_EXPAND_SUPPORTED)
3359 PNG_EXTERN void png_do_expand_palette PNGARG((png_row_infop row_info,
3360 png_bytep row, png_colorp palette, png_bytep trans, int num_trans));
3361 PNG_EXTERN void png_do_expand PNGARG((png_row_infop row_info,
3362 png_bytep row, png_color_16p trans_value));
3363 #endif
3364
3365 /* The following decodes the appropriate chunks, and does error correction,
3366 * then calls the appropriate callback for the chunk if it is valid.
3367 */
3368
3369 /* decode the IHDR chunk */
3370 PNG_EXTERN void png_handle_IHDR PNGARG((png_structp png_ptr, png_infop info_ptr,
3371 png_uint_32 length));
3372 PNG_EXTERN void png_handle_PLTE PNGARG((png_structp png_ptr, png_infop info_ptr,
3373 png_uint_32 length));
3374 PNG_EXTERN void png_handle_IEND PNGARG((png_structp png_ptr, png_infop info_ptr,
3375 png_uint_32 length));
3376
3377 #if defined(PNG_READ_bKGD_SUPPORTED)
3378 PNG_EXTERN void png_handle_bKGD PNGARG((png_structp png_ptr, png_infop info_ptr,
3379 png_uint_32 length));
3380 #endif
3381
3382 #if defined(PNG_READ_cHRM_SUPPORTED)
3383 PNG_EXTERN void png_handle_cHRM PNGARG((png_structp png_ptr, png_infop info_ptr,
3384 png_uint_32 length));
3385 #endif
3386
3387 #if defined(PNG_READ_gAMA_SUPPORTED)
3388 PNG_EXTERN void png_handle_gAMA PNGARG((png_structp png_ptr, png_infop info_ptr,
3389 png_uint_32 length));
3390 #endif
3391
3392 #if defined(PNG_READ_hIST_SUPPORTED)
3393 PNG_EXTERN void png_handle_hIST PNGARG((png_structp png_ptr, png_infop info_ptr,
3394 png_uint_32 length));
3395 #endif
3396
3397 #if defined(PNG_READ_iCCP_SUPPORTED)
3398 extern void png_handle_iCCP PNGARG((png_structp png_ptr, png_infop info_ptr,
3399 png_uint_32 length));
3400 #endif /* PNG_READ_iCCP_SUPPORTED */
3401
3402 #if defined(PNG_READ_iTXt_SUPPORTED)
3403 PNG_EXTERN void png_handle_iTXt PNGARG((png_structp png_ptr, png_infop info_ptr,
3404 png_uint_32 length));
3405 #endif
3406
3407 #if defined(PNG_READ_oFFs_SUPPORTED)
3408 PNG_EXTERN void png_handle_oFFs PNGARG((png_structp png_ptr, png_infop info_ptr,
3409 png_uint_32 length));
3410 #endif
3411
3412 #if defined(PNG_READ_pCAL_SUPPORTED)
3413 PNG_EXTERN void png_handle_pCAL PNGARG((png_structp png_ptr, png_infop info_ptr,
3414 png_uint_32 length));
3415 #endif
3416
3417 #if defined(PNG_READ_pHYs_SUPPORTED)
3418 PNG_EXTERN void png_handle_pHYs PNGARG((png_structp png_ptr, png_infop info_ptr,
3419 png_uint_32 length));
3420 #endif
3421
3422 #if defined(PNG_READ_sBIT_SUPPORTED)
3423 PNG_EXTERN void png_handle_sBIT PNGARG((png_structp png_ptr, png_infop info_ptr,
3424 png_uint_32 length));
3425 #endif
3426
3427 #if defined(PNG_READ_sCAL_SUPPORTED)
3428 PNG_EXTERN void png_handle_sCAL PNGARG((png_structp png_ptr, png_infop info_ptr,
3429 png_uint_32 length));
3430 #endif
3431
3432 #if defined(PNG_READ_sPLT_SUPPORTED)
3433 extern void png_handle_sPLT PNGARG((png_structp png_ptr, png_infop info_ptr,
3434 png_uint_32 length));
3435 #endif /* PNG_READ_sPLT_SUPPORTED */
3436
3437 #if defined(PNG_READ_sRGB_SUPPORTED)
3438 PNG_EXTERN void png_handle_sRGB PNGARG((png_structp png_ptr, png_infop info_ptr,
3439 png_uint_32 length));
3440 #endif
3441
3442 #if defined(PNG_READ_tEXt_SUPPORTED)
3443 PNG_EXTERN void png_handle_tEXt PNGARG((png_structp png_ptr, png_infop info_ptr,
3444 png_uint_32 length));
3445 #endif
3446
3447 #if defined(PNG_READ_tIME_SUPPORTED)
3448 PNG_EXTERN void png_handle_tIME PNGARG((png_structp png_ptr, png_infop info_ptr,
3449 png_uint_32 length));
3450 #endif
3451
3452 #if defined(PNG_READ_tRNS_SUPPORTED)
3453 PNG_EXTERN void png_handle_tRNS PNGARG((png_structp png_ptr, png_infop info_ptr,
3454 png_uint_32 length));
3455 #endif
3456
3457 #if defined(PNG_READ_zTXt_SUPPORTED)
3458 PNG_EXTERN void png_handle_zTXt PNGARG((png_structp png_ptr, png_infop info_ptr,
3459 png_uint_32 length));
3460 #endif
3461
3462 PNG_EXTERN void png_handle_unknown PNGARG((png_structp png_ptr,
3463 png_infop info_ptr, png_uint_32 length));
3464
3465 PNG_EXTERN void png_check_chunk_name PNGARG((png_structp png_ptr,
3466 png_bytep chunk_name));
3467
3468 /* handle the transformations for reading and writing */
3469 PNG_EXTERN void png_do_read_transformations PNGARG((png_structp png_ptr));
3470 PNG_EXTERN void png_do_write_transformations PNGARG((png_structp png_ptr));
3471
3472 PNG_EXTERN void png_init_read_transformations PNGARG((png_structp png_ptr));
3473
3474 #ifdef PNG_PROGRESSIVE_READ_SUPPORTED
3475 PNG_EXTERN void png_push_read_chunk PNGARG((png_structp png_ptr,
3476 png_infop info_ptr));
3477 PNG_EXTERN void png_push_read_sig PNGARG((png_structp png_ptr,
3478 png_infop info_ptr));
3479 PNG_EXTERN void png_push_check_crc PNGARG((png_structp png_ptr));
3480 PNG_EXTERN void png_push_crc_skip PNGARG((png_structp png_ptr,
3481 png_uint_32 length));
3482 PNG_EXTERN void png_push_crc_finish PNGARG((png_structp png_ptr));
3483 PNG_EXTERN void png_push_save_buffer PNGARG((png_structp png_ptr));
3484 PNG_EXTERN void png_push_restore_buffer PNGARG((png_structp png_ptr,
3485 png_bytep buffer, png_size_t buffer_length));
3486 PNG_EXTERN void png_push_read_IDAT PNGARG((png_structp png_ptr));
3487 PNG_EXTERN void png_process_IDAT_data PNGARG((png_structp png_ptr,
3488 png_bytep buffer, png_size_t buffer_length));
3489 PNG_EXTERN void png_push_process_row PNGARG((png_structp png_ptr));
3490 PNG_EXTERN void png_push_handle_unknown PNGARG((png_structp png_ptr,
3491 png_infop info_ptr, png_uint_32 length));
3492 PNG_EXTERN void png_push_have_info PNGARG((png_structp png_ptr,
3493 png_infop info_ptr));
3494 PNG_EXTERN void png_push_have_end PNGARG((png_structp png_ptr,
3495 png_infop info_ptr));
3496 PNG_EXTERN void png_push_have_row PNGARG((png_structp png_ptr, png_bytep row));
3497 PNG_EXTERN void png_push_read_end PNGARG((png_structp png_ptr,
3498 png_infop info_ptr));
3499 PNG_EXTERN void png_process_some_data PNGARG((png_structp png_ptr,
3500 png_infop info_ptr));
3501 PNG_EXTERN void png_read_push_finish_row PNGARG((png_structp png_ptr));
3502 #if defined(PNG_READ_tEXt_SUPPORTED)
3503 PNG_EXTERN void png_push_handle_tEXt PNGARG((png_structp png_ptr,
3504 png_infop info_ptr, png_uint_32 length));
3505 PNG_EXTERN void png_push_read_tEXt PNGARG((png_structp png_ptr,
3506 png_infop info_ptr));
3507 #endif
3508 #if defined(PNG_READ_zTXt_SUPPORTED)
3509 PNG_EXTERN void png_push_handle_zTXt PNGARG((png_structp png_ptr,
3510 png_infop info_ptr, png_uint_32 length));
3511 PNG_EXTERN void png_push_read_zTXt PNGARG((png_structp png_ptr,
3512 png_infop info_ptr));
3513 #endif
3514 #if defined(PNG_READ_iTXt_SUPPORTED)
3515 PNG_EXTERN void png_push_handle_iTXt PNGARG((png_structp png_ptr,
3516 png_infop info_ptr, png_uint_32 length));
3517 PNG_EXTERN void png_push_read_iTXt PNGARG((png_structp png_ptr,
3518 png_infop info_ptr));
3519 #endif
3520
3521 #endif /* PNG_PROGRESSIVE_READ_SUPPORTED */
3522
3523 #ifdef PNG_MNG_FEATURES_SUPPORTED
3524 PNG_EXTERN void png_do_read_intrapixel PNGARG((png_row_infop row_info,
3525 png_bytep row));
3526 PNG_EXTERN void png_do_write_intrapixel PNGARG((png_row_infop row_info,
3527 png_bytep row));
3528 #endif
3529
3530 #if defined(PNG_ASSEMBLER_CODE_SUPPORTED)
3531 #if defined(PNG_MMX_CODE_SUPPORTED)
3532 /* png.c */ /* PRIVATE */
3533 PNG_EXTERN void png_init_mmx_flags PNGARG((png_structp png_ptr));
3534 #endif
3535 #endif
3536
3537 #if defined(PNG_INCH_CONVERSIONS) && defined(PNG_FLOATING_POINT_SUPPORTED)
3538 PNG_EXTERN png_uint_32 png_get_pixels_per_inch PNGARG((png_structp png_ptr,
3539 png_infop info_ptr));
3540
3541 PNG_EXTERN png_uint_32 png_get_x_pixels_per_inch PNGARG((png_structp png_ptr,
3542 png_infop info_ptr));
3543
3544 PNG_EXTERN png_uint_32 png_get_y_pixels_per_inch PNGARG((png_structp png_ptr,
3545 png_infop info_ptr));
3546
3547 PNG_EXTERN float png_get_x_offset_inches PNGARG((png_structp png_ptr,
3548 png_infop info_ptr));
3549
3550 PNG_EXTERN float png_get_y_offset_inches PNGARG((png_structp png_ptr,
3551 png_infop info_ptr));
3552
3553 #if defined(PNG_pHYs_SUPPORTED)
3554 PNG_EXTERN png_uint_32 png_get_pHYs_dpi PNGARG((png_structp png_ptr,
3555 png_infop info_ptr, png_uint_32 *res_x, png_uint_32 *res_y, int *unit_type));
3556 #endif /* PNG_pHYs_SUPPORTED */
3557 #endif /* PNG_INCH_CONVERSIONS && PNG_FLOATING_POINT_SUPPORTED */
3558
3559 /* Maintainer: Put new private prototypes here ^ and in libpngpf.3 */
3560
3561 #endif /* PNG_INTERNAL */
3562
3563 #ifdef __cplusplus
3564 }
3565 #endif
3566
3567 #endif /* PNG_VERSION_INFO_ONLY */
3568 /* do not put anything past this line */
3569 #endif /* PNG_H */