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1/* png.h - header file for PNG reference library
2 *
3 * libpng version 1.2.34 - December 18, 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 1.2.34 - December 18, 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 * 1.0.37 10 10037 10.so.0.37[.0]
196 * 1.2.30beta01-04 13 10230 12.so.0.30[.0]
197 * 1.0.38rc01-08 10 10038 10.so.0.38[.0]
198 * 1.2.30rc01-08 13 10230 12.so.0.30[.0]
199 * 1.0.38 10 10038 10.so.0.38[.0]
200 * 1.2.30 13 10230 12.so.0.30[.0]
201 * 1.0.39rc01-03 10 10039 10.so.0.39[.0]
202 * 1.2.31rc01-03 13 10231 12.so.0.31[.0]
203 * 1.0.39 10 10039 10.so.0.39[.0]
204 * 1.2.31 13 10231 12.so.0.31[.0]
205 * 1.2.32beta01-02 13 10232 12.so.0.32[.0]
206 * 1.0.40rc01 10 10040 10.so.0.40[.0]
207 * 1.2.32rc01 13 10232 12.so.0.32[.0]
208 * 1.0.40 10 10040 10.so.0.40[.0]
209 * 1.2.32 13 10232 12.so.0.32[.0]
210 * 1.2.33beta01-02 13 10233 12.so.0.33[.0]
211 * 1.2.33rc01-02 13 10233 12.so.0.33[.0]
212 * 1.0.41rc01 10 10041 10.so.0.41[.0]
213 * 1.2.33 13 10233 12.so.0.33[.0]
214 * 1.0.41 10 10041 10.so.0.41[.0]
215 * 1.2.34beta01-07 13 10234 12.so.0.34[.0]
216 * 1.0.42rc01 10 10042 10.so.0.42[.0]
217 * 1.2.34rc01 13 10234 12.so.0.34[.0]
218 * 1.0.42 10 10042 10.so.0.42[.0]
219 * 1.2.34 13 10234 12.so.0.34[.0]
220 *
221 * Henceforth the source version will match the shared-library major
222 * and minor numbers; the shared-library major version number will be
223 * used for changes in backward compatibility, as it is intended. The
224 * PNG_LIBPNG_VER macro, which is not used within libpng but is available
225 * for applications, is an unsigned integer of the form xyyzz corresponding
226 * to the source version x.y.z (leading zeros in y and z). Beta versions
227 * were given the previous public release number plus a letter, until
228 * version 1.0.6j; from then on they were given the upcoming public
229 * release number plus "betaNN" or "rcNN".
230 *
231 * Binary incompatibility exists only when applications make direct access
232 * to the info_ptr or png_ptr members through png.h, and the compiled
233 * application is loaded with a different version of the library.
234 *
235 * DLLNUM will change each time there are forward or backward changes
236 * in binary compatibility (e.g., when a new feature is added).
237 *
238 * See libpng.txt or libpng.3 for more information. The PNG specification
239 * is available as a W3C Recommendation and as an ISO Specification,
240 * <http://www.w3.org/TR/2003/REC-PNG-20031110/
241 */
242
243/*
244 * COPYRIGHT NOTICE, DISCLAIMER, and LICENSE:
245 *
246 * If you modify libpng you may insert additional notices immediately following
247 * this sentence.
248 *
249 * libpng versions 1.2.6, August 15, 2004, through 1.2.34, December 18, 2008, are
250 * Copyright (c) 2004, 2006-2008 Glenn Randers-Pehrson, and are
251 * distributed according to the same disclaimer and license as libpng-1.2.5
252 * with the following individual added to the list of Contributing Authors:
253 *
254 * Cosmin Truta
255 *
256 * libpng versions 1.0.7, July 1, 2000, through 1.2.5, October 3, 2002, are
257 * Copyright (c) 2000-2002 Glenn Randers-Pehrson, and are
258 * distributed according to the same disclaimer and license as libpng-1.0.6
259 * with the following individuals added to the list of Contributing Authors:
260 *
261 * Simon-Pierre Cadieux
262 * Eric S. Raymond
263 * Gilles Vollant
264 *
265 * and with the following additions to the disclaimer:
266 *
267 * There is no warranty against interference with your enjoyment of the
268 * library or against infringement. There is no warranty that our
269 * efforts or the library will fulfill any of your particular purposes
270 * or needs. This library is provided with all faults, and the entire
271 * risk of satisfactory quality, performance, accuracy, and effort is with
272 * the user.
273 *
274 * libpng versions 0.97, January 1998, through 1.0.6, March 20, 2000, are
275 * Copyright (c) 1998, 1999, 2000 Glenn Randers-Pehrson, and are
276 * distributed according to the same disclaimer and license as libpng-0.96,
277 * with the following individuals added to the list of Contributing Authors:
278 *
279 * Tom Lane
280 * Glenn Randers-Pehrson
281 * Willem van Schaik
282 *
283 * libpng versions 0.89, June 1996, through 0.96, May 1997, are
284 * Copyright (c) 1996, 1997 Andreas Dilger
285 * Distributed according to the same disclaimer and license as libpng-0.88,
286 * with the following individuals added to the list of Contributing Authors:
287 *
288 * John Bowler
289 * Kevin Bracey
290 * Sam Bushell
291 * Magnus Holmgren
292 * Greg Roelofs
293 * Tom Tanner
294 *
295 * libpng versions 0.5, May 1995, through 0.88, January 1996, are
296 * Copyright (c) 1995, 1996 Guy Eric Schalnat, Group 42, Inc.
297 *
298 * For the purposes of this copyright and license, "Contributing Authors"
299 * is defined as the following set of individuals:
300 *
301 * Andreas Dilger
302 * Dave Martindale
303 * Guy Eric Schalnat
304 * Paul Schmidt
305 * Tim Wegner
306 *
307 * The PNG Reference Library is supplied "AS IS". The Contributing Authors
308 * and Group 42, Inc. disclaim all warranties, expressed or implied,
309 * including, without limitation, the warranties of merchantability and of
310 * fitness for any purpose. The Contributing Authors and Group 42, Inc.
311 * assume no liability for direct, indirect, incidental, special, exemplary,
312 * or consequential damages, which may result from the use of the PNG
313 * Reference Library, even if advised of the possibility of such damage.
314 *
315 * Permission is hereby granted to use, copy, modify, and distribute this
316 * source code, or portions hereof, for any purpose, without fee, subject
317 * to the following restrictions:
318 *
319 * 1. The origin of this source code must not be misrepresented.
320 *
321 * 2. Altered versions must be plainly marked as such and
322 * must not be misrepresented as being the original source.
323 *
324 * 3. This Copyright notice may not be removed or altered from
325 * any source or altered source distribution.
326 *
327 * The Contributing Authors and Group 42, Inc. specifically permit, without
328 * fee, and encourage the use of this source code as a component to
329 * supporting the PNG file format in commercial products. If you use this
330 * source code in a product, acknowledgment is not required but would be
331 * appreciated.
332 */
333
334/*
335 * A "png_get_copyright" function is available, for convenient use in "about"
336 * boxes and the like:
337 *
338 * printf("%s",png_get_copyright(NULL));
339 *
340 * Also, the PNG logo (in PNG format, of course) is supplied in the
341 * files "pngbar.png" and "pngbar.jpg (88x31) and "pngnow.png" (98x31).
342 */
343
344/*
345 * Libpng is OSI Certified Open Source Software. OSI Certified is a
346 * certification mark of the Open Source Initiative.
347 */
348
349/*
350 * The contributing authors would like to thank all those who helped
351 * with testing, bug fixes, and patience. This wouldn't have been
352 * possible without all of you.
353 *
354 * Thanks to Frank J. T. Wojcik for helping with the documentation.
355 */
356
357/*
358 * Y2K compliance in libpng:
359 * =========================
360 *
361 * December 18, 2008
362 *
363 * Since the PNG Development group is an ad-hoc body, we can't make
364 * an official declaration.
365 *
366 * This is your unofficial assurance that libpng from version 0.71 and
367 * upward through 1.2.34 are Y2K compliant. It is my belief that earlier
368 * versions were also Y2K compliant.
369 *
370 * Libpng only has three year fields. One is a 2-byte unsigned integer
371 * that will hold years up to 65535. The other two hold the date in text
372 * format, and will hold years up to 9999.
373 *
374 * The integer is
375 * "png_uint_16 year" in png_time_struct.
376 *
377 * The strings are
378 * "png_charp time_buffer" in png_struct and
379 * "near_time_buffer", which is a local character string in png.c.
380 *
381 * There are seven time-related functions:
382 * png.c: png_convert_to_rfc_1123() in png.c
383 * (formerly png_convert_to_rfc_1152() in error)
384 * png_convert_from_struct_tm() in pngwrite.c, called in pngwrite.c
385 * png_convert_from_time_t() in pngwrite.c
386 * png_get_tIME() in pngget.c
387 * png_handle_tIME() in pngrutil.c, called in pngread.c
388 * png_set_tIME() in pngset.c
389 * png_write_tIME() in pngwutil.c, called in pngwrite.c
390 *
391 * All handle dates properly in a Y2K environment. The
392 * png_convert_from_time_t() function calls gmtime() to convert from system
393 * clock time, which returns (year - 1900), which we properly convert to
394 * the full 4-digit year. There is a possibility that applications using
395 * libpng are not passing 4-digit years into the png_convert_to_rfc_1123()
396 * function, or that they are incorrectly passing only a 2-digit year
397 * instead of "year - 1900" into the png_convert_from_struct_tm() function,
398 * but this is not under our control. The libpng documentation has always
399 * stated that it works with 4-digit years, and the APIs have been
400 * documented as such.
401 *
402 * The tIME chunk itself is also Y2K compliant. It uses a 2-byte unsigned
403 * integer to hold the year, and can hold years as large as 65535.
404 *
405 * zlib, upon which libpng depends, is also Y2K compliant. It contains
406 * no date-related code.
407 *
408 * Glenn Randers-Pehrson
409 * libpng maintainer
410 * PNG Development Group
411 */
412
413#ifndef PNG_H
414#define PNG_H
415
416/* This is not the place to learn how to use libpng. The file libpng.txt
417 * describes how to use libpng, and the file example.c summarizes it
418 * with some code on which to build. This file is useful for looking
419 * at the actual function definitions and structure components.
420 */
421
422/* Version information for png.h - this should match the version in png.c */
423#define PNG_LIBPNG_VER_STRING "1.2.34"
424#define PNG_HEADER_VERSION_STRING \
425 " libpng version 1.2.34 - December 18, 2008\n"
426
427#define PNG_LIBPNG_VER_SONUM 0
428#define PNG_LIBPNG_VER_DLLNUM 13
429
430/* These should match the first 3 components of PNG_LIBPNG_VER_STRING: */
431#define PNG_LIBPNG_VER_MAJOR 1
432#define PNG_LIBPNG_VER_MINOR 2
433#define PNG_LIBPNG_VER_RELEASE 34
434/* This should match the numeric part of the final component of
435 * PNG_LIBPNG_VER_STRING, omitting any leading zero: */
436
437#define PNG_LIBPNG_VER_BUILD 0
438
439/* Release Status */
440#define PNG_LIBPNG_BUILD_ALPHA 1
441#define PNG_LIBPNG_BUILD_BETA 2
442#define PNG_LIBPNG_BUILD_RC 3
443#define PNG_LIBPNG_BUILD_STABLE 4
444#define PNG_LIBPNG_BUILD_RELEASE_STATUS_MASK 7
445
446/* Release-Specific Flags */
447#define PNG_LIBPNG_BUILD_PATCH 8 /* Can be OR'ed with
448 PNG_LIBPNG_BUILD_STABLE only */
449#define PNG_LIBPNG_BUILD_PRIVATE 16 /* Cannot be OR'ed with
450 PNG_LIBPNG_BUILD_SPECIAL */
451#define PNG_LIBPNG_BUILD_SPECIAL 32 /* Cannot be OR'ed with
452 PNG_LIBPNG_BUILD_PRIVATE */
453
454#define PNG_LIBPNG_BUILD_BASE_TYPE PNG_LIBPNG_BUILD_STABLE
455
456/* Careful here. At one time, Guy wanted to use 082, but that would be octal.
457 * We must not include leading zeros.
458 * Versions 0.7 through 1.0.0 were in the range 0 to 100 here (only
459 * version 1.0.0 was mis-numbered 100 instead of 10000). From
460 * version 1.0.1 it's xxyyzz, where x=major, y=minor, z=release */
461#define PNG_LIBPNG_VER 10234 /* 1.2.34 */
462
463#ifndef PNG_VERSION_INFO_ONLY
464/* include the compression library's header */
465#include "zlib.h"
466#endif
467
468/* include all user configurable info, including optional assembler routines */
469#include "pngconf.h"
470
471/*
472 * Added at libpng-1.2.8 */
473/* Ref MSDN: Private as priority over Special
474 * VS_FF_PRIVATEBUILD File *was not* built using standard release
475 * procedures. If this value is given, the StringFileInfo block must
476 * contain a PrivateBuild string.
477 *
478 * VS_FF_SPECIALBUILD File *was* built by the original company using
479 * standard release procedures but is a variation of the standard
480 * file of the same version number. If this value is given, the
481 * StringFileInfo block must contain a SpecialBuild string.
482 */
483
484#if defined(PNG_USER_PRIVATEBUILD)
485# define PNG_LIBPNG_BUILD_TYPE \
486 (PNG_LIBPNG_BUILD_BASE_TYPE | PNG_LIBPNG_BUILD_PRIVATE)
487#else
488# if defined(PNG_LIBPNG_SPECIALBUILD)
489# define PNG_LIBPNG_BUILD_TYPE \
490 (PNG_LIBPNG_BUILD_BASE_TYPE | PNG_LIBPNG_BUILD_SPECIAL)
491# else
492# define PNG_LIBPNG_BUILD_TYPE (PNG_LIBPNG_BUILD_BASE_TYPE)
493# endif
494#endif
495
496#ifndef PNG_VERSION_INFO_ONLY
497
498/* Inhibit C++ name-mangling for libpng functions but not for system calls. */
499#ifdef __cplusplus
500extern "C" {
501#endif /* __cplusplus */
502
503/* This file is arranged in several sections. The first section contains
504 * structure and type definitions. The second section contains the external
505 * library functions, while the third has the internal library functions,
506 * which applications aren't expected to use directly.
507 */
508
509#ifndef PNG_NO_TYPECAST_NULL
510#define int_p_NULL (int *)NULL
511#define png_bytep_NULL (png_bytep)NULL
512#define png_bytepp_NULL (png_bytepp)NULL
513#define png_doublep_NULL (png_doublep)NULL
514#define png_error_ptr_NULL (png_error_ptr)NULL
515#define png_flush_ptr_NULL (png_flush_ptr)NULL
516#define png_free_ptr_NULL (png_free_ptr)NULL
517#define png_infopp_NULL (png_infopp)NULL
518#define png_malloc_ptr_NULL (png_malloc_ptr)NULL
519#define png_read_status_ptr_NULL (png_read_status_ptr)NULL
520#define png_rw_ptr_NULL (png_rw_ptr)NULL
521#define png_structp_NULL (png_structp)NULL
522#define png_uint_16p_NULL (png_uint_16p)NULL
523#define png_voidp_NULL (png_voidp)NULL
524#define png_write_status_ptr_NULL (png_write_status_ptr)NULL
525#else
526#define int_p_NULL NULL
527#define png_bytep_NULL NULL
528#define png_bytepp_NULL NULL
529#define png_doublep_NULL NULL
530#define png_error_ptr_NULL NULL
531#define png_flush_ptr_NULL NULL
532#define png_free_ptr_NULL NULL
533#define png_infopp_NULL NULL
534#define png_malloc_ptr_NULL NULL
535#define png_read_status_ptr_NULL NULL
536#define png_rw_ptr_NULL NULL
537#define png_structp_NULL NULL
538#define png_uint_16p_NULL NULL
539#define png_voidp_NULL NULL
540#define png_write_status_ptr_NULL NULL
541#endif
542
543/* variables declared in png.c - only it needs to define PNG_NO_EXTERN */
544#if !defined(PNG_NO_EXTERN) || defined(PNG_ALWAYS_EXTERN)
545/* Version information for C files, stored in png.c. This had better match
546 * the version above.
547 */
548#ifdef PNG_USE_GLOBAL_ARRAYS
549PNG_EXPORT_VAR (PNG_CONST char) png_libpng_ver[18];
550 /* need room for 99.99.99beta99z */
551#else
552#define png_libpng_ver png_get_header_ver(NULL)
553#endif
554
555#ifdef PNG_USE_GLOBAL_ARRAYS
556/* This was removed in version 1.0.5c */
557/* Structures to facilitate easy interlacing. See png.c for more details */
558PNG_EXPORT_VAR (PNG_CONST int FARDATA) png_pass_start[7];
559PNG_EXPORT_VAR (PNG_CONST int FARDATA) png_pass_inc[7];
560PNG_EXPORT_VAR (PNG_CONST int FARDATA) png_pass_ystart[7];
561PNG_EXPORT_VAR (PNG_CONST int FARDATA) png_pass_yinc[7];
562PNG_EXPORT_VAR (PNG_CONST int FARDATA) png_pass_mask[7];
563PNG_EXPORT_VAR (PNG_CONST int FARDATA) png_pass_dsp_mask[7];
564/* This isn't currently used. If you need it, see png.c for more details.
565PNG_EXPORT_VAR (PNG_CONST int FARDATA) png_pass_height[7];
566*/
567#endif
568
569#endif /* PNG_NO_EXTERN */
570
571/* Three color definitions. The order of the red, green, and blue, (and the
572 * exact size) is not important, although the size of the fields need to
573 * be png_byte or png_uint_16 (as defined below).
574 */
575typedef struct png_color_struct
576{
577 png_byte red;
578 png_byte green;
579 png_byte blue;
580} png_color;
581typedef png_color FAR * png_colorp;
582typedef png_color FAR * FAR * png_colorpp;
583
584typedef struct png_color_16_struct
585{
586 png_byte index; /* used for palette files */
587 png_uint_16 red; /* for use in red green blue files */
588 png_uint_16 green;
589 png_uint_16 blue;
590 png_uint_16 gray; /* for use in grayscale files */
591} png_color_16;
592typedef png_color_16 FAR * png_color_16p;
593typedef png_color_16 FAR * FAR * png_color_16pp;
594
595typedef struct png_color_8_struct
596{
597 png_byte red; /* for use in red green blue files */
598 png_byte green;
599 png_byte blue;
600 png_byte gray; /* for use in grayscale files */
601 png_byte alpha; /* for alpha channel files */
602} png_color_8;
603typedef png_color_8 FAR * png_color_8p;
604typedef png_color_8 FAR * FAR * png_color_8pp;
605
606/*
607 * The following two structures are used for the in-core representation
608 * of sPLT chunks.
609 */
610typedef struct png_sPLT_entry_struct
611{
612 png_uint_16 red;
613 png_uint_16 green;
614 png_uint_16 blue;
615 png_uint_16 alpha;
616 png_uint_16 frequency;
617} png_sPLT_entry;
618typedef png_sPLT_entry FAR * png_sPLT_entryp;
619typedef png_sPLT_entry FAR * FAR * png_sPLT_entrypp;
620
621/* When the depth of the sPLT palette is 8 bits, the color and alpha samples
622 * occupy the LSB of their respective members, and the MSB of each member
623 * is zero-filled. The frequency member always occupies the full 16 bits.
624 */
625
626typedef struct png_sPLT_struct
627{
628 png_charp name; /* palette name */
629 png_byte depth; /* depth of palette samples */
630 png_sPLT_entryp entries; /* palette entries */
631 png_int_32 nentries; /* number of palette entries */
632} png_sPLT_t;
633typedef png_sPLT_t FAR * png_sPLT_tp;
634typedef png_sPLT_t FAR * FAR * png_sPLT_tpp;
635
636#ifdef PNG_TEXT_SUPPORTED
637/* png_text holds the contents of a text/ztxt/itxt chunk in a PNG file,
638 * and whether that contents is compressed or not. The "key" field
639 * points to a regular zero-terminated C string. The "text", "lang", and
640 * "lang_key" fields can be regular C strings, empty strings, or NULL pointers.
641 * However, the * structure returned by png_get_text() will always contain
642 * regular zero-terminated C strings (possibly empty), never NULL pointers,
643 * so they can be safely used in printf() and other string-handling functions.
644 */
645typedef struct png_text_struct
646{
647 int compression; /* compression value:
648 -1: tEXt, none
649 0: zTXt, deflate
650 1: iTXt, none
651 2: iTXt, deflate */
652 png_charp key; /* keyword, 1-79 character description of "text" */
653 png_charp text; /* comment, may be an empty string (ie "")
654 or a NULL pointer */
655 png_size_t text_length; /* length of the text string */
656#ifdef PNG_iTXt_SUPPORTED
657 png_size_t itxt_length; /* length of the itxt string */
658 png_charp lang; /* language code, 0-79 characters
659 or a NULL pointer */
660 png_charp lang_key; /* keyword translated UTF-8 string, 0 or more
661 chars or a NULL pointer */
662#endif
663} png_text;
664typedef png_text FAR * png_textp;
665typedef png_text FAR * FAR * png_textpp;
666#endif
667
668/* Supported compression types for text in PNG files (tEXt, and zTXt).
669 * The values of the PNG_TEXT_COMPRESSION_ defines should NOT be changed. */
670#define PNG_TEXT_COMPRESSION_NONE_WR -3
671#define PNG_TEXT_COMPRESSION_zTXt_WR -2
672#define PNG_TEXT_COMPRESSION_NONE -1
673#define PNG_TEXT_COMPRESSION_zTXt 0
674#define PNG_ITXT_COMPRESSION_NONE 1
675#define PNG_ITXT_COMPRESSION_zTXt 2
676#define PNG_TEXT_COMPRESSION_LAST 3 /* Not a valid value */
677
678/* png_time is a way to hold the time in an machine independent way.
679 * Two conversions are provided, both from time_t and struct tm. There
680 * is no portable way to convert to either of these structures, as far
681 * as I know. If you know of a portable way, send it to me. As a side
682 * note - PNG has always been Year 2000 compliant!
683 */
684typedef struct png_time_struct
685{
686 png_uint_16 year; /* full year, as in, 1995 */
687 png_byte month; /* month of year, 1 - 12 */
688 png_byte day; /* day of month, 1 - 31 */
689 png_byte hour; /* hour of day, 0 - 23 */
690 png_byte minute; /* minute of hour, 0 - 59 */
691 png_byte second; /* second of minute, 0 - 60 (for leap seconds) */
692} png_time;
693typedef png_time FAR * png_timep;
694typedef png_time FAR * FAR * png_timepp;
695
696#if defined(PNG_UNKNOWN_CHUNKS_SUPPORTED)
697/* png_unknown_chunk is a structure to hold queued chunks for which there is
698 * no specific support. The idea is that we can use this to queue
699 * up private chunks for output even though the library doesn't actually
700 * know about their semantics.
701 */
702#define PNG_CHUNK_NAME_LENGTH 5
703typedef struct png_unknown_chunk_t
704{
705 png_byte name[PNG_CHUNK_NAME_LENGTH];
706 png_byte *data;
707 png_size_t size;
708
709 /* libpng-using applications should NOT directly modify this byte. */
710 png_byte location; /* mode of operation at read time */
711}
712png_unknown_chunk;
713typedef png_unknown_chunk FAR * png_unknown_chunkp;
714typedef png_unknown_chunk FAR * FAR * png_unknown_chunkpp;
715#endif
716
717/* png_info is a structure that holds the information in a PNG file so
718 * that the application can find out the characteristics of the image.
719 * If you are reading the file, this structure will tell you what is
720 * in the PNG file. If you are writing the file, fill in the information
721 * you want to put into the PNG file, then call png_write_info().
722 * The names chosen should be very close to the PNG specification, so
723 * consult that document for information about the meaning of each field.
724 *
725 * With libpng < 0.95, it was only possible to directly set and read the
726 * the values in the png_info_struct, which meant that the contents and
727 * order of the values had to remain fixed. With libpng 0.95 and later,
728 * however, there are now functions that abstract the contents of
729 * png_info_struct from the application, so this makes it easier to use
730 * libpng with dynamic libraries, and even makes it possible to use
731 * libraries that don't have all of the libpng ancillary chunk-handing
732 * functionality.
733 *
734 * In any case, the order of the parameters in png_info_struct should NOT
735 * be changed for as long as possible to keep compatibility with applications
736 * that use the old direct-access method with png_info_struct.
737 *
738 * The following members may have allocated storage attached that should be
739 * cleaned up before the structure is discarded: palette, trans, text,
740 * pcal_purpose, pcal_units, pcal_params, hist, iccp_name, iccp_profile,
741 * splt_palettes, scal_unit, row_pointers, and unknowns. By default, these
742 * are automatically freed when the info structure is deallocated, if they were
743 * allocated internally by libpng. This behavior can be changed by means
744 * of the png_data_freer() function.
745 *
746 * More allocation details: all the chunk-reading functions that
747 * change these members go through the corresponding png_set_*
748 * functions. A function to clear these members is available: see
749 * png_free_data(). The png_set_* functions do not depend on being
750 * able to point info structure members to any of the storage they are
751 * passed (they make their own copies), EXCEPT that the png_set_text
752 * functions use the same storage passed to them in the text_ptr or
753 * itxt_ptr structure argument, and the png_set_rows and png_set_unknowns
754 * functions do not make their own copies.
755 */
756typedef struct png_info_struct
757{
758 /* the following are necessary for every PNG file */
759 png_uint_32 width; /* width of image in pixels (from IHDR) */
760 png_uint_32 height; /* height of image in pixels (from IHDR) */
761 png_uint_32 valid; /* valid chunk data (see PNG_INFO_ below) */
762 png_uint_32 rowbytes; /* bytes needed to hold an untransformed row */
763 png_colorp palette; /* array of color values (valid & PNG_INFO_PLTE) */
764 png_uint_16 num_palette; /* number of color entries in "palette" (PLTE) */
765 png_uint_16 num_trans; /* number of transparent palette color (tRNS) */
766 png_byte bit_depth; /* 1, 2, 4, 8, or 16 bits/channel (from IHDR) */
767 png_byte color_type; /* see PNG_COLOR_TYPE_ below (from IHDR) */
768 /* The following three should have been named *_method not *_type */
769 png_byte compression_type; /* must be PNG_COMPRESSION_TYPE_BASE (IHDR) */
770 png_byte filter_type; /* must be PNG_FILTER_TYPE_BASE (from IHDR) */
771 png_byte interlace_type; /* One of PNG_INTERLACE_NONE, PNG_INTERLACE_ADAM7 */
772
773 /* The following is informational only on read, and not used on writes. */
774 png_byte channels; /* number of data channels per pixel (1, 2, 3, 4) */
775 png_byte pixel_depth; /* number of bits per pixel */
776 png_byte spare_byte; /* to align the data, and for future use */
777 png_byte signature[8]; /* magic bytes read by libpng from start of file */
778
779 /* The rest of the data is optional. If you are reading, check the
780 * valid field to see if the information in these are valid. If you
781 * are writing, set the valid field to those chunks you want written,
782 * and initialize the appropriate fields below.
783 */
784
785#if defined(PNG_gAMA_SUPPORTED) && defined(PNG_FLOATING_POINT_SUPPORTED)
786 /* The gAMA chunk describes the gamma characteristics of the system
787 * on which the image was created, normally in the range [1.0, 2.5].
788 * Data is valid if (valid & PNG_INFO_gAMA) is non-zero.
789 */
790 float gamma; /* gamma value of image, if (valid & PNG_INFO_gAMA) */
791#endif
792
793#if defined(PNG_sRGB_SUPPORTED)
794 /* GR-P, 0.96a */
795 /* Data valid if (valid & PNG_INFO_sRGB) non-zero. */
796 png_byte srgb_intent; /* sRGB rendering intent [0, 1, 2, or 3] */
797#endif
798
799#if defined(PNG_TEXT_SUPPORTED)
800 /* The tEXt, and zTXt chunks contain human-readable textual data in
801 * uncompressed, compressed, and optionally compressed forms, respectively.
802 * The data in "text" is an array of pointers to uncompressed,
803 * null-terminated C strings. Each chunk has a keyword that describes the
804 * textual data contained in that chunk. Keywords are not required to be
805 * unique, and the text string may be empty. Any number of text chunks may
806 * be in an image.
807 */
808 int num_text; /* number of comments read/to write */
809 int max_text; /* current size of text array */
810 png_textp text; /* array of comments read/to write */
811#endif /* PNG_TEXT_SUPPORTED */
812
813#if defined(PNG_tIME_SUPPORTED)
814 /* The tIME chunk holds the last time the displayed image data was
815 * modified. See the png_time struct for the contents of this struct.
816 */
817 png_time mod_time;
818#endif
819
820#if defined(PNG_sBIT_SUPPORTED)
821 /* The sBIT chunk specifies the number of significant high-order bits
822 * in the pixel data. Values are in the range [1, bit_depth], and are
823 * only specified for the channels in the pixel data. The contents of
824 * the low-order bits is not specified. Data is valid if
825 * (valid & PNG_INFO_sBIT) is non-zero.
826 */
827 png_color_8 sig_bit; /* significant bits in color channels */
828#endif
829
830#if defined(PNG_tRNS_SUPPORTED) || defined(PNG_READ_EXPAND_SUPPORTED) || \
831defined(PNG_READ_BACKGROUND_SUPPORTED)
832 /* The tRNS chunk supplies transparency data for paletted images and
833 * other image types that don't need a full alpha channel. There are
834 * "num_trans" transparency values for a paletted image, stored in the
835 * same order as the palette colors, starting from index 0. Values
836 * for the data are in the range [0, 255], ranging from fully transparent
837 * to fully opaque, respectively. For non-paletted images, there is a
838 * single color specified that should be treated as fully transparent.
839 * Data is valid if (valid & PNG_INFO_tRNS) is non-zero.
840 */
841 png_bytep trans; /* transparent values for paletted image */
842 png_color_16 trans_values; /* transparent color for non-palette image */
843#endif
844
845#if defined(PNG_bKGD_SUPPORTED) || defined(PNG_READ_BACKGROUND_SUPPORTED)
846 /* The bKGD chunk gives the suggested image background color if the
847 * display program does not have its own background color and the image
848 * is needs to composited onto a background before display. The colors
849 * in "background" are normally in the same color space/depth as the
850 * pixel data. Data is valid if (valid & PNG_INFO_bKGD) is non-zero.
851 */
852 png_color_16 background;
853#endif
854
855#if defined(PNG_oFFs_SUPPORTED)
856 /* The oFFs chunk gives the offset in "offset_unit_type" units rightwards
857 * and downwards from the top-left corner of the display, page, or other
858 * application-specific co-ordinate space. See the PNG_OFFSET_ defines
859 * below for the unit types. Valid if (valid & PNG_INFO_oFFs) non-zero.
860 */
861 png_int_32 x_offset; /* x offset on page */
862 png_int_32 y_offset; /* y offset on page */
863 png_byte offset_unit_type; /* offset units type */
864#endif
865
866#if defined(PNG_pHYs_SUPPORTED)
867 /* The pHYs chunk gives the physical pixel density of the image for
868 * display or printing in "phys_unit_type" units (see PNG_RESOLUTION_
869 * defines below). Data is valid if (valid & PNG_INFO_pHYs) is non-zero.
870 */
871 png_uint_32 x_pixels_per_unit; /* horizontal pixel density */
872 png_uint_32 y_pixels_per_unit; /* vertical pixel density */
873 png_byte phys_unit_type; /* resolution type (see PNG_RESOLUTION_ below) */
874#endif
875
876#if defined(PNG_hIST_SUPPORTED)
877 /* The hIST chunk contains the relative frequency or importance of the
878 * various palette entries, so that a viewer can intelligently select a
879 * reduced-color palette, if required. Data is an array of "num_palette"
880 * values in the range [0,65535]. Data valid if (valid & PNG_INFO_hIST)
881 * is non-zero.
882 */
883 png_uint_16p hist;
884#endif
885
886#ifdef PNG_cHRM_SUPPORTED
887 /* The cHRM chunk describes the CIE color characteristics of the monitor
888 * on which the PNG was created. This data allows the viewer to do gamut
889 * mapping of the input image to ensure that the viewer sees the same
890 * colors in the image as the creator. Values are in the range
891 * [0.0, 0.8]. Data valid if (valid & PNG_INFO_cHRM) non-zero.
892 */
893#ifdef PNG_FLOATING_POINT_SUPPORTED
894 float x_white;
895 float y_white;
896 float x_red;
897 float y_red;
898 float x_green;
899 float y_green;
900 float x_blue;
901 float y_blue;
902#endif
903#endif
904
905#if defined(PNG_pCAL_SUPPORTED)
906 /* The pCAL chunk describes a transformation between the stored pixel
907 * values and original physical data values used to create the image.
908 * The integer range [0, 2^bit_depth - 1] maps to the floating-point
909 * range given by [pcal_X0, pcal_X1], and are further transformed by a
910 * (possibly non-linear) transformation function given by "pcal_type"
911 * and "pcal_params" into "pcal_units". Please see the PNG_EQUATION_
912 * defines below, and the PNG-Group's PNG extensions document for a
913 * complete description of the transformations and how they should be
914 * implemented, and for a description of the ASCII parameter strings.
915 * Data values are valid if (valid & PNG_INFO_pCAL) non-zero.
916 */
917 png_charp pcal_purpose; /* pCAL chunk description string */
918 png_int_32 pcal_X0; /* minimum value */
919 png_int_32 pcal_X1; /* maximum value */
920 png_charp pcal_units; /* Latin-1 string giving physical units */
921 png_charpp pcal_params; /* ASCII strings containing parameter values */
922 png_byte pcal_type; /* equation type (see PNG_EQUATION_ below) */
923 png_byte pcal_nparams; /* number of parameters given in pcal_params */
924#endif
925
926/* New members added in libpng-1.0.6 */
927#ifdef PNG_FREE_ME_SUPPORTED
928 png_uint_32 free_me; /* flags items libpng is responsible for freeing */
929#endif
930
931#if defined(PNG_UNKNOWN_CHUNKS_SUPPORTED)
932 /* storage for unknown chunks that the library doesn't recognize. */
933 png_unknown_chunkp unknown_chunks;
934 png_size_t unknown_chunks_num;
935#endif
936
937#if defined(PNG_iCCP_SUPPORTED)
938 /* iCCP chunk data. */
939 png_charp iccp_name; /* profile name */
940 png_charp iccp_profile; /* International Color Consortium profile data */
941 /* Note to maintainer: should be png_bytep */
942 png_uint_32 iccp_proflen; /* ICC profile data length */
943 png_byte iccp_compression; /* Always zero */
944#endif
945
946#if defined(PNG_sPLT_SUPPORTED)
947 /* data on sPLT chunks (there may be more than one). */
948 png_sPLT_tp splt_palettes;
949 png_uint_32 splt_palettes_num;
950#endif
951
952#if defined(PNG_sCAL_SUPPORTED)
953 /* The sCAL chunk describes the actual physical dimensions of the
954 * subject matter of the graphic. The chunk contains a unit specification
955 * a byte value, and two ASCII strings representing floating-point
956 * values. The values are width and height corresponsing to one pixel
957 * in the image. This external representation is converted to double
958 * here. Data values are valid if (valid & PNG_INFO_sCAL) is non-zero.
959 */
960 png_byte scal_unit; /* unit of physical scale */
961#ifdef PNG_FLOATING_POINT_SUPPORTED
962 double scal_pixel_width; /* width of one pixel */
963 double scal_pixel_height; /* height of one pixel */
964#endif
965#ifdef PNG_FIXED_POINT_SUPPORTED
966 png_charp scal_s_width; /* string containing height */
967 png_charp scal_s_height; /* string containing width */
968#endif
969#endif
970
971#if defined(PNG_INFO_IMAGE_SUPPORTED)
972 /* Memory has been allocated if (valid & PNG_ALLOCATED_INFO_ROWS) non-zero */
973 /* Data valid if (valid & PNG_INFO_IDAT) non-zero */
974 png_bytepp row_pointers; /* the image bits */
975#endif
976
977#if defined(PNG_FIXED_POINT_SUPPORTED) && defined(PNG_gAMA_SUPPORTED)
978 png_fixed_point int_gamma; /* gamma of image, if (valid & PNG_INFO_gAMA) */
979#endif
980
981#if defined(PNG_cHRM_SUPPORTED) && defined(PNG_FIXED_POINT_SUPPORTED)
982 png_fixed_point int_x_white;
983 png_fixed_point int_y_white;
984 png_fixed_point int_x_red;
985 png_fixed_point int_y_red;
986 png_fixed_point int_x_green;
987 png_fixed_point int_y_green;
988 png_fixed_point int_x_blue;
989 png_fixed_point int_y_blue;
990#endif
991
992} png_info;
993
994typedef png_info FAR * png_infop;
995typedef png_info FAR * FAR * png_infopp;
996
997/* Maximum positive integer used in PNG is (2^31)-1 */
998#define PNG_UINT_31_MAX ((png_uint_32)0x7fffffffL)
999#define PNG_UINT_32_MAX ((png_uint_32)(-1))
1000#define PNG_SIZE_MAX ((png_size_t)(-1))
1001#if defined(PNG_1_0_X) || defined (PNG_1_2_X)
1002/* PNG_MAX_UINT is deprecated; use PNG_UINT_31_MAX instead. */
1003#define PNG_MAX_UINT PNG_UINT_31_MAX
1004#endif
1005
1006/* These describe the color_type field in png_info. */
1007/* color type masks */
1008#define PNG_COLOR_MASK_PALETTE 1
1009#define PNG_COLOR_MASK_COLOR 2
1010#define PNG_COLOR_MASK_ALPHA 4
1011
1012/* color types. Note that not all combinations are legal */
1013#define PNG_COLOR_TYPE_GRAY 0
1014#define PNG_COLOR_TYPE_PALETTE (PNG_COLOR_MASK_COLOR | PNG_COLOR_MASK_PALETTE)
1015#define PNG_COLOR_TYPE_RGB (PNG_COLOR_MASK_COLOR)
1016#define PNG_COLOR_TYPE_RGB_ALPHA (PNG_COLOR_MASK_COLOR | PNG_COLOR_MASK_ALPHA)
1017#define PNG_COLOR_TYPE_GRAY_ALPHA (PNG_COLOR_MASK_ALPHA)
1018/* aliases */
1019#define PNG_COLOR_TYPE_RGBA PNG_COLOR_TYPE_RGB_ALPHA
1020#define PNG_COLOR_TYPE_GA PNG_COLOR_TYPE_GRAY_ALPHA
1021
1022/* This is for compression type. PNG 1.0-1.2 only define the single type. */
1023#define PNG_COMPRESSION_TYPE_BASE 0 /* Deflate method 8, 32K window */
1024#define PNG_COMPRESSION_TYPE_DEFAULT PNG_COMPRESSION_TYPE_BASE
1025
1026/* This is for filter type. PNG 1.0-1.2 only define the single type. */
1027#define PNG_FILTER_TYPE_BASE 0 /* Single row per-byte filtering */
1028#define PNG_INTRAPIXEL_DIFFERENCING 64 /* Used only in MNG datastreams */
1029#define PNG_FILTER_TYPE_DEFAULT PNG_FILTER_TYPE_BASE
1030
1031/* These are for the interlacing type. These values should NOT be changed. */
1032#define PNG_INTERLACE_NONE 0 /* Non-interlaced image */
1033#define PNG_INTERLACE_ADAM7 1 /* Adam7 interlacing */
1034#define PNG_INTERLACE_LAST 2 /* Not a valid value */
1035
1036/* These are for the oFFs chunk. These values should NOT be changed. */
1037#define PNG_OFFSET_PIXEL 0 /* Offset in pixels */
1038#define PNG_OFFSET_MICROMETER 1 /* Offset in micrometers (1/10^6 meter) */
1039#define PNG_OFFSET_LAST 2 /* Not a valid value */
1040
1041/* These are for the pCAL chunk. These values should NOT be changed. */
1042#define PNG_EQUATION_LINEAR 0 /* Linear transformation */
1043#define PNG_EQUATION_BASE_E 1 /* Exponential base e transform */
1044#define PNG_EQUATION_ARBITRARY 2 /* Arbitrary base exponential transform */
1045#define PNG_EQUATION_HYPERBOLIC 3 /* Hyperbolic sine transformation */
1046#define PNG_EQUATION_LAST 4 /* Not a valid value */
1047
1048/* These are for the sCAL chunk. These values should NOT be changed. */
1049#define PNG_SCALE_UNKNOWN 0 /* unknown unit (image scale) */
1050#define PNG_SCALE_METER 1 /* meters per pixel */
1051#define PNG_SCALE_RADIAN 2 /* radians per pixel */
1052#define PNG_SCALE_LAST 3 /* Not a valid value */
1053
1054/* These are for the pHYs chunk. These values should NOT be changed. */
1055#define PNG_RESOLUTION_UNKNOWN 0 /* pixels/unknown unit (aspect ratio) */
1056#define PNG_RESOLUTION_METER 1 /* pixels/meter */
1057#define PNG_RESOLUTION_LAST 2 /* Not a valid value */
1058
1059/* These are for the sRGB chunk. These values should NOT be changed. */
1060#define PNG_sRGB_INTENT_PERCEPTUAL 0
1061#define PNG_sRGB_INTENT_RELATIVE 1
1062#define PNG_sRGB_INTENT_SATURATION 2
1063#define PNG_sRGB_INTENT_ABSOLUTE 3
1064#define PNG_sRGB_INTENT_LAST 4 /* Not a valid value */
1065
1066/* This is for text chunks */
1067#define PNG_KEYWORD_MAX_LENGTH 79
1068
1069/* Maximum number of entries in PLTE/sPLT/tRNS arrays */
1070#define PNG_MAX_PALETTE_LENGTH 256
1071
1072/* These determine if an ancillary chunk's data has been successfully read
1073 * from the PNG header, or if the application has filled in the corresponding
1074 * data in the info_struct to be written into the output file. The values
1075 * of the PNG_INFO_<chunk> defines should NOT be changed.
1076 */
1077#define PNG_INFO_gAMA 0x0001
1078#define PNG_INFO_sBIT 0x0002
1079#define PNG_INFO_cHRM 0x0004
1080#define PNG_INFO_PLTE 0x0008
1081#define PNG_INFO_tRNS 0x0010
1082#define PNG_INFO_bKGD 0x0020
1083#define PNG_INFO_hIST 0x0040
1084#define PNG_INFO_pHYs 0x0080
1085#define PNG_INFO_oFFs 0x0100
1086#define PNG_INFO_tIME 0x0200
1087#define PNG_INFO_pCAL 0x0400
1088#define PNG_INFO_sRGB 0x0800 /* GR-P, 0.96a */
1089#define PNG_INFO_iCCP 0x1000 /* ESR, 1.0.6 */
1090#define PNG_INFO_sPLT 0x2000 /* ESR, 1.0.6 */
1091#define PNG_INFO_sCAL 0x4000 /* ESR, 1.0.6 */
1092#define PNG_INFO_IDAT 0x8000L /* ESR, 1.0.6 */
1093
1094/* This is used for the transformation routines, as some of them
1095 * change these values for the row. It also should enable using
1096 * the routines for other purposes.
1097 */
1098typedef struct png_row_info_struct
1099{
1100 png_uint_32 width; /* width of row */
1101 png_uint_32 rowbytes; /* number of bytes in row */
1102 png_byte color_type; /* color type of row */
1103 png_byte bit_depth; /* bit depth of row */
1104 png_byte channels; /* number of channels (1, 2, 3, or 4) */
1105 png_byte pixel_depth; /* bits per pixel (depth * channels) */
1106} png_row_info;
1107
1108typedef png_row_info FAR * png_row_infop;
1109typedef png_row_info FAR * FAR * png_row_infopp;
1110
1111/* These are the function types for the I/O functions and for the functions
1112 * that allow the user to override the default I/O functions with his or her
1113 * own. The png_error_ptr type should match that of user-supplied warning
1114 * and error functions, while the png_rw_ptr type should match that of the
1115 * user read/write data functions.
1116 */
1117typedef struct png_struct_def png_struct;
1118typedef png_struct FAR * png_structp;
1119
1120typedef void (PNGAPI *png_error_ptr) PNGARG((png_structp, png_const_charp));
1121typedef void (PNGAPI *png_rw_ptr) PNGARG((png_structp, png_bytep, png_size_t));
1122typedef void (PNGAPI *png_flush_ptr) PNGARG((png_structp));
1123typedef void (PNGAPI *png_read_status_ptr) PNGARG((png_structp, png_uint_32,
1124 int));
1125typedef void (PNGAPI *png_write_status_ptr) PNGARG((png_structp, png_uint_32,
1126 int));
1127
1128#ifdef PNG_PROGRESSIVE_READ_SUPPORTED
1129typedef void (PNGAPI *png_progressive_info_ptr) PNGARG((png_structp, png_infop));
1130typedef void (PNGAPI *png_progressive_end_ptr) PNGARG((png_structp, png_infop));
1131typedef void (PNGAPI *png_progressive_row_ptr) PNGARG((png_structp, png_bytep,
1132 png_uint_32, int));
1133#endif
1134
1135#if defined(PNG_READ_USER_TRANSFORM_SUPPORTED) || \
1136 defined(PNG_WRITE_USER_TRANSFORM_SUPPORTED) || \
1137 defined(PNG_LEGACY_SUPPORTED)
1138typedef void (PNGAPI *png_user_transform_ptr) PNGARG((png_structp,
1139 png_row_infop, png_bytep));
1140#endif
1141
1142#if defined(PNG_USER_CHUNKS_SUPPORTED)
1143typedef int (PNGAPI *png_user_chunk_ptr) PNGARG((png_structp, png_unknown_chunkp));
1144#endif
1145#if defined(PNG_UNKNOWN_CHUNKS_SUPPORTED)
1146typedef void (PNGAPI *png_unknown_chunk_ptr) PNGARG((png_structp));
1147#endif
1148
1149/* Transform masks for the high-level interface */
1150#define PNG_TRANSFORM_IDENTITY 0x0000 /* read and write */
1151#define PNG_TRANSFORM_STRIP_16 0x0001 /* read only */
1152#define PNG_TRANSFORM_STRIP_ALPHA 0x0002 /* read only */
1153#define PNG_TRANSFORM_PACKING 0x0004 /* read and write */
1154#define PNG_TRANSFORM_PACKSWAP 0x0008 /* read and write */
1155#define PNG_TRANSFORM_EXPAND 0x0010 /* read only */
1156#define PNG_TRANSFORM_INVERT_MONO 0x0020 /* read and write */
1157#define PNG_TRANSFORM_SHIFT 0x0040 /* read and write */
1158#define PNG_TRANSFORM_BGR 0x0080 /* read and write */
1159#define PNG_TRANSFORM_SWAP_ALPHA 0x0100 /* read and write */
1160#define PNG_TRANSFORM_SWAP_ENDIAN 0x0200 /* read and write */
1161#define PNG_TRANSFORM_INVERT_ALPHA 0x0400 /* read and write */
1162#define PNG_TRANSFORM_STRIP_FILLER 0x0800 /* WRITE only, deprecated */
1163/* Added to libpng-1.2.34 */
1164#define PNG_TRANSFORM_STRIP_FILLER_BEFORE 0x0800 /* WRITE only */
1165#define PNG_TRANSFORM_STRIP_FILLER_AFTER 0x1000 /* WRITE only */
1166
1167/* Flags for MNG supported features */
1168#define PNG_FLAG_MNG_EMPTY_PLTE 0x01
1169#define PNG_FLAG_MNG_FILTER_64 0x04
1170#define PNG_ALL_MNG_FEATURES 0x05
1171
1172typedef png_voidp (*png_malloc_ptr) PNGARG((png_structp, png_size_t));
1173typedef void (*png_free_ptr) PNGARG((png_structp, png_voidp));
1174
1175/* The structure that holds the information to read and write PNG files.
1176 * The only people who need to care about what is inside of this are the
1177 * people who will be modifying the library for their own special needs.
1178 * It should NOT be accessed directly by an application, except to store
1179 * the jmp_buf.
1180 */
1181
1182struct png_struct_def
1183{
1184#ifdef PNG_SETJMP_SUPPORTED
1185 jmp_buf jmpbuf; /* used in png_error */
1186#endif
1187 png_error_ptr error_fn; /* function for printing errors and aborting */
1188 png_error_ptr warning_fn; /* function for printing warnings */
1189 png_voidp error_ptr; /* user supplied struct for error functions */
1190 png_rw_ptr write_data_fn; /* function for writing output data */
1191 png_rw_ptr read_data_fn; /* function for reading input data */
1192 png_voidp io_ptr; /* ptr to application struct for I/O functions */
1193
1194#if defined(PNG_READ_USER_TRANSFORM_SUPPORTED)
1195 png_user_transform_ptr read_user_transform_fn; /* user read transform */
1196#endif
1197
1198#if defined(PNG_WRITE_USER_TRANSFORM_SUPPORTED)
1199 png_user_transform_ptr write_user_transform_fn; /* user write transform */
1200#endif
1201
1202/* These were added in libpng-1.0.2 */
1203#if defined(PNG_USER_TRANSFORM_PTR_SUPPORTED)
1204#if defined(PNG_READ_USER_TRANSFORM_SUPPORTED) || \
1205 defined(PNG_WRITE_USER_TRANSFORM_SUPPORTED)
1206 png_voidp user_transform_ptr; /* user supplied struct for user transform */
1207 png_byte user_transform_depth; /* bit depth of user transformed pixels */
1208 png_byte user_transform_channels; /* channels in user transformed pixels */
1209#endif
1210#endif
1211
1212 png_uint_32 mode; /* tells us where we are in the PNG file */
1213 png_uint_32 flags; /* flags indicating various things to libpng */
1214 png_uint_32 transformations; /* which transformations to perform */
1215
1216 z_stream zstream; /* pointer to decompression structure (below) */
1217 png_bytep zbuf; /* buffer for zlib */
1218 png_size_t zbuf_size; /* size of zbuf */
1219 int zlib_level; /* holds zlib compression level */
1220 int zlib_method; /* holds zlib compression method */
1221 int zlib_window_bits; /* holds zlib compression window bits */
1222 int zlib_mem_level; /* holds zlib compression memory level */
1223 int zlib_strategy; /* holds zlib compression strategy */
1224
1225 png_uint_32 width; /* width of image in pixels */
1226 png_uint_32 height; /* height of image in pixels */
1227 png_uint_32 num_rows; /* number of rows in current pass */
1228 png_uint_32 usr_width; /* width of row at start of write */
1229 png_uint_32 rowbytes; /* size of row in bytes */
1230 png_uint_32 irowbytes; /* size of current interlaced row in bytes */
1231 png_uint_32 iwidth; /* width of current interlaced row in pixels */
1232 png_uint_32 row_number; /* current row in interlace pass */
1233 png_bytep prev_row; /* buffer to save previous (unfiltered) row */
1234 png_bytep row_buf; /* buffer to save current (unfiltered) row */
1235#ifndef PNG_NO_WRITE_FILTER
1236 png_bytep sub_row; /* buffer to save "sub" row when filtering */
1237 png_bytep up_row; /* buffer to save "up" row when filtering */
1238 png_bytep avg_row; /* buffer to save "avg" row when filtering */
1239 png_bytep paeth_row; /* buffer to save "Paeth" row when filtering */
1240#endif
1241 png_row_info row_info; /* used for transformation routines */
1242
1243 png_uint_32 idat_size; /* current IDAT size for read */
1244 png_uint_32 crc; /* current chunk CRC value */
1245 png_colorp palette; /* palette from the input file */
1246 png_uint_16 num_palette; /* number of color entries in palette */
1247 png_uint_16 num_trans; /* number of transparency values */
1248 png_byte chunk_name[5]; /* null-terminated name of current chunk */
1249 png_byte compression; /* file compression type (always 0) */
1250 png_byte filter; /* file filter type (always 0) */
1251 png_byte interlaced; /* PNG_INTERLACE_NONE, PNG_INTERLACE_ADAM7 */
1252 png_byte pass; /* current interlace pass (0 - 6) */
1253 png_byte do_filter; /* row filter flags (see PNG_FILTER_ below ) */
1254 png_byte color_type; /* color type of file */
1255 png_byte bit_depth; /* bit depth of file */
1256 png_byte usr_bit_depth; /* bit depth of users row */
1257 png_byte pixel_depth; /* number of bits per pixel */
1258 png_byte channels; /* number of channels in file */
1259 png_byte usr_channels; /* channels at start of write */
1260 png_byte sig_bytes; /* magic bytes read/written from start of file */
1261
1262#if defined(PNG_READ_FILLER_SUPPORTED) || defined(PNG_WRITE_FILLER_SUPPORTED)
1263#ifdef PNG_LEGACY_SUPPORTED
1264 png_byte filler; /* filler byte for pixel expansion */
1265#else
1266 png_uint_16 filler; /* filler bytes for pixel expansion */
1267#endif
1268#endif
1269
1270#if defined(PNG_bKGD_SUPPORTED)
1271 png_byte background_gamma_type;
1272# ifdef PNG_FLOATING_POINT_SUPPORTED
1273 float background_gamma;
1274# endif
1275 png_color_16 background; /* background color in screen gamma space */
1276#if defined(PNG_READ_GAMMA_SUPPORTED)
1277 png_color_16 background_1; /* background normalized to gamma 1.0 */
1278#endif
1279#endif /* PNG_bKGD_SUPPORTED */
1280
1281#if defined(PNG_WRITE_FLUSH_SUPPORTED)
1282 png_flush_ptr output_flush_fn;/* Function for flushing output */
1283 png_uint_32 flush_dist; /* how many rows apart to flush, 0 - no flush */
1284 png_uint_32 flush_rows; /* number of rows written since last flush */
1285#endif
1286
1287#if defined(PNG_READ_GAMMA_SUPPORTED) || defined(PNG_READ_BACKGROUND_SUPPORTED)
1288 int gamma_shift; /* number of "insignificant" bits 16-bit gamma */
1289#ifdef PNG_FLOATING_POINT_SUPPORTED
1290 float gamma; /* file gamma value */
1291 float screen_gamma; /* screen gamma value (display_exponent) */
1292#endif
1293#endif
1294
1295#if defined(PNG_READ_GAMMA_SUPPORTED) || defined(PNG_READ_BACKGROUND_SUPPORTED)
1296 png_bytep gamma_table; /* gamma table for 8-bit depth files */
1297 png_bytep gamma_from_1; /* converts from 1.0 to screen */
1298 png_bytep gamma_to_1; /* converts from file to 1.0 */
1299 png_uint_16pp gamma_16_table; /* gamma table for 16-bit depth files */
1300 png_uint_16pp gamma_16_from_1; /* converts from 1.0 to screen */
1301 png_uint_16pp gamma_16_to_1; /* converts from file to 1.0 */
1302#endif
1303
1304#if defined(PNG_READ_GAMMA_SUPPORTED) || defined(PNG_sBIT_SUPPORTED)
1305 png_color_8 sig_bit; /* significant bits in each available channel */
1306#endif
1307
1308#if defined(PNG_READ_SHIFT_SUPPORTED) || defined(PNG_WRITE_SHIFT_SUPPORTED)
1309 png_color_8 shift; /* shift for significant bit tranformation */
1310#endif
1311
1312#if defined(PNG_tRNS_SUPPORTED) || defined(PNG_READ_BACKGROUND_SUPPORTED) \
1313 || defined(PNG_READ_EXPAND_SUPPORTED) || defined(PNG_READ_BACKGROUND_SUPPORTED)
1314 png_bytep trans; /* transparency values for paletted files */
1315 png_color_16 trans_values; /* transparency values for non-paletted files */
1316#endif
1317
1318 png_read_status_ptr read_row_fn; /* called after each row is decoded */
1319 png_write_status_ptr write_row_fn; /* called after each row is encoded */
1320#ifdef PNG_PROGRESSIVE_READ_SUPPORTED
1321 png_progressive_info_ptr info_fn; /* called after header data fully read */
1322 png_progressive_row_ptr row_fn; /* called after each prog. row is decoded */
1323 png_progressive_end_ptr end_fn; /* called after image is complete */
1324 png_bytep save_buffer_ptr; /* current location in save_buffer */
1325 png_bytep save_buffer; /* buffer for previously read data */
1326 png_bytep current_buffer_ptr; /* current location in current_buffer */
1327 png_bytep current_buffer; /* buffer for recently used data */
1328 png_uint_32 push_length; /* size of current input chunk */
1329 png_uint_32 skip_length; /* bytes to skip in input data */
1330 png_size_t save_buffer_size; /* amount of data now in save_buffer */
1331 png_size_t save_buffer_max; /* total size of save_buffer */
1332 png_size_t buffer_size; /* total amount of available input data */
1333 png_size_t current_buffer_size; /* amount of data now in current_buffer */
1334 int process_mode; /* what push library is currently doing */
1335 int cur_palette; /* current push library palette index */
1336
1337# if defined(PNG_TEXT_SUPPORTED)
1338 png_size_t current_text_size; /* current size of text input data */
1339 png_size_t current_text_left; /* how much text left to read in input */
1340 png_charp current_text; /* current text chunk buffer */
1341 png_charp current_text_ptr; /* current location in current_text */
1342# endif /* PNG_TEXT_SUPPORTED */
1343#endif /* PNG_PROGRESSIVE_READ_SUPPORTED */
1344
1345#if defined(__TURBOC__) && !defined(_Windows) && !defined(__FLAT__)
1346/* for the Borland special 64K segment handler */
1347 png_bytepp offset_table_ptr;
1348 png_bytep offset_table;
1349 png_uint_16 offset_table_number;
1350 png_uint_16 offset_table_count;
1351 png_uint_16 offset_table_count_free;
1352#endif
1353
1354#if defined(PNG_READ_DITHER_SUPPORTED)
1355 png_bytep palette_lookup; /* lookup table for dithering */
1356 png_bytep dither_index; /* index translation for palette files */
1357#endif
1358
1359#if defined(PNG_READ_DITHER_SUPPORTED) || defined(PNG_hIST_SUPPORTED)
1360 png_uint_16p hist; /* histogram */
1361#endif
1362
1363#if defined(PNG_WRITE_WEIGHTED_FILTER_SUPPORTED)
1364 png_byte heuristic_method; /* heuristic for row filter selection */
1365 png_byte num_prev_filters; /* number of weights for previous rows */
1366 png_bytep prev_filters; /* filter type(s) of previous row(s) */
1367 png_uint_16p filter_weights; /* weight(s) for previous line(s) */
1368 png_uint_16p inv_filter_weights; /* 1/weight(s) for previous line(s) */
1369 png_uint_16p filter_costs; /* relative filter calculation cost */
1370 png_uint_16p inv_filter_costs; /* 1/relative filter calculation cost */
1371#endif
1372
1373#if defined(PNG_TIME_RFC1123_SUPPORTED)
1374 png_charp time_buffer; /* String to hold RFC 1123 time text */
1375#endif
1376
1377/* New members added in libpng-1.0.6 */
1378
1379#ifdef PNG_FREE_ME_SUPPORTED
1380 png_uint_32 free_me; /* flags items libpng is responsible for freeing */
1381#endif
1382
1383#if defined(PNG_USER_CHUNKS_SUPPORTED)
1384 png_voidp user_chunk_ptr;
1385 png_user_chunk_ptr read_user_chunk_fn; /* user read chunk handler */
1386#endif
1387
1388#if defined(PNG_UNKNOWN_CHUNKS_SUPPORTED)
1389 int num_chunk_list;
1390 png_bytep chunk_list;
1391#endif
1392
1393/* New members added in libpng-1.0.3 */
1394#if defined(PNG_READ_RGB_TO_GRAY_SUPPORTED)
1395 png_byte rgb_to_gray_status;
1396 /* These were changed from png_byte in libpng-1.0.6 */
1397 png_uint_16 rgb_to_gray_red_coeff;
1398 png_uint_16 rgb_to_gray_green_coeff;
1399 png_uint_16 rgb_to_gray_blue_coeff;
1400#endif
1401
1402/* New member added in libpng-1.0.4 (renamed in 1.0.9) */
1403#if defined(PNG_MNG_FEATURES_SUPPORTED) || \
1404 defined(PNG_READ_EMPTY_PLTE_SUPPORTED) || \
1405 defined(PNG_WRITE_EMPTY_PLTE_SUPPORTED)
1406/* changed from png_byte to png_uint_32 at version 1.2.0 */
1407#ifdef PNG_1_0_X
1408 png_byte mng_features_permitted;
1409#else
1410 png_uint_32 mng_features_permitted;
1411#endif /* PNG_1_0_X */
1412#endif
1413
1414/* New member added in libpng-1.0.7 */
1415#if defined(PNG_READ_GAMMA_SUPPORTED) || defined(PNG_READ_BACKGROUND_SUPPORTED)
1416 png_fixed_point int_gamma;
1417#endif
1418
1419/* New member added in libpng-1.0.9, ifdef'ed out in 1.0.12, enabled in 1.2.0 */
1420#if defined(PNG_MNG_FEATURES_SUPPORTED)
1421 png_byte filter_type;
1422#endif
1423
1424#if defined(PNG_1_0_X)
1425/* New member added in libpng-1.0.10, ifdef'ed out in 1.2.0 */
1426 png_uint_32 row_buf_size;
1427#endif
1428
1429/* New members added in libpng-1.2.0 */
1430#if defined(PNG_ASSEMBLER_CODE_SUPPORTED)
1431# if !defined(PNG_1_0_X)
1432# if defined(PNG_MMX_CODE_SUPPORTED)
1433 png_byte mmx_bitdepth_threshold;
1434 png_uint_32 mmx_rowbytes_threshold;
1435# endif
1436 png_uint_32 asm_flags;
1437# endif
1438#endif
1439
1440/* New members added in libpng-1.0.2 but first enabled by default in 1.2.0 */
1441#ifdef PNG_USER_MEM_SUPPORTED
1442 png_voidp mem_ptr; /* user supplied struct for mem functions */
1443 png_malloc_ptr malloc_fn; /* function for allocating memory */
1444 png_free_ptr free_fn; /* function for freeing memory */
1445#endif
1446
1447/* New member added in libpng-1.0.13 and 1.2.0 */
1448 png_bytep big_row_buf; /* buffer to save current (unfiltered) row */
1449
1450#if defined(PNG_READ_DITHER_SUPPORTED)
1451/* The following three members were added at version 1.0.14 and 1.2.4 */
1452 png_bytep dither_sort; /* working sort array */
1453 png_bytep index_to_palette; /* where the original index currently is */
1454 /* in the palette */
1455 png_bytep palette_to_index; /* which original index points to this */
1456 /* palette color */
1457#endif
1458
1459/* New members added in libpng-1.0.16 and 1.2.6 */
1460 png_byte compression_type;
1461
1462#ifdef PNG_SET_USER_LIMITS_SUPPORTED
1463 png_uint_32 user_width_max;
1464 png_uint_32 user_height_max;
1465#endif
1466
1467/* New member added in libpng-1.0.25 and 1.2.17 */
1468#if defined(PNG_UNKNOWN_CHUNKS_SUPPORTED)
1469 /* storage for unknown chunk that the library doesn't recognize. */
1470 png_unknown_chunk unknown_chunk;
1471#endif
1472
1473/* New members added in libpng-1.2.26 */
1474 png_uint_32 old_big_row_buf_size, old_prev_row_size;
1475
1476/* New member added in libpng-1.2.30 */
1477 png_charp chunkdata; /* buffer for reading chunk data */
1478
1479};
1480
1481
1482/* This triggers a compiler error in png.c, if png.c and png.h
1483 * do not agree upon the version number.
1484 */
1485typedef png_structp version_1_2_34;
1486
1487typedef png_struct FAR * FAR * png_structpp;
1488
1489/* Here are the function definitions most commonly used. This is not
1490 * the place to find out how to use libpng. See libpng.txt for the
1491 * full explanation, see example.c for the summary. This just provides
1492 * a simple one line description of the use of each function.
1493 */
1494
1495/* Returns the version number of the library */
1496extern PNG_EXPORT(png_uint_32,png_access_version_number) PNGARG((void));
1497
1498/* Tell lib we have already handled the first <num_bytes> magic bytes.
1499 * Handling more than 8 bytes from the beginning of the file is an error.
1500 */
1501extern PNG_EXPORT(void,png_set_sig_bytes) PNGARG((png_structp png_ptr,
1502 int num_bytes));
1503
1504/* Check sig[start] through sig[start + num_to_check - 1] to see if it's a
1505 * PNG file. Returns zero if the supplied bytes match the 8-byte PNG
1506 * signature, and non-zero otherwise. Having num_to_check == 0 or
1507 * start > 7 will always fail (ie return non-zero).
1508 */
1509extern PNG_EXPORT(int,png_sig_cmp) PNGARG((png_bytep sig, png_size_t start,
1510 png_size_t num_to_check));
1511
1512/* Simple signature checking function. This is the same as calling
1513 * png_check_sig(sig, n) := !png_sig_cmp(sig, 0, n).
1514 */
1515extern PNG_EXPORT(int,png_check_sig) PNGARG((png_bytep sig, int num));
1516
1517/* Allocate and initialize png_ptr struct for reading, and any other memory. */
1518extern PNG_EXPORT(png_structp,png_create_read_struct)
1519 PNGARG((png_const_charp user_png_ver, png_voidp error_ptr,
1520 png_error_ptr error_fn, png_error_ptr warn_fn));
1521
1522/* Allocate and initialize png_ptr struct for writing, and any other memory */
1523extern PNG_EXPORT(png_structp,png_create_write_struct)
1524 PNGARG((png_const_charp user_png_ver, png_voidp error_ptr,
1525 png_error_ptr error_fn, png_error_ptr warn_fn));
1526
1527#ifdef PNG_WRITE_SUPPORTED
1528extern PNG_EXPORT(png_uint_32,png_get_compression_buffer_size)
1529 PNGARG((png_structp png_ptr));
1530#endif
1531
1532#ifdef PNG_WRITE_SUPPORTED
1533extern PNG_EXPORT(void,png_set_compression_buffer_size)
1534 PNGARG((png_structp png_ptr, png_uint_32 size));
1535#endif
1536
1537/* Reset the compression stream */
1538extern PNG_EXPORT(int,png_reset_zstream) PNGARG((png_structp png_ptr));
1539
1540/* New functions added in libpng-1.0.2 (not enabled by default until 1.2.0) */
1541#ifdef PNG_USER_MEM_SUPPORTED
1542extern PNG_EXPORT(png_structp,png_create_read_struct_2)
1543 PNGARG((png_const_charp user_png_ver, png_voidp error_ptr,
1544 png_error_ptr error_fn, png_error_ptr warn_fn, png_voidp mem_ptr,
1545 png_malloc_ptr malloc_fn, png_free_ptr free_fn));
1546extern PNG_EXPORT(png_structp,png_create_write_struct_2)
1547 PNGARG((png_const_charp user_png_ver, png_voidp error_ptr,
1548 png_error_ptr error_fn, png_error_ptr warn_fn, png_voidp mem_ptr,
1549 png_malloc_ptr malloc_fn, png_free_ptr free_fn));
1550#endif
1551
1552/* Write a PNG chunk - size, type, (optional) data, CRC. */
1553extern PNG_EXPORT(void,png_write_chunk) PNGARG((png_structp png_ptr,
1554 png_bytep chunk_name, png_bytep data, png_size_t length));
1555
1556/* Write the start of a PNG chunk - length and chunk name. */
1557extern PNG_EXPORT(void,png_write_chunk_start) PNGARG((png_structp png_ptr,
1558 png_bytep chunk_name, png_uint_32 length));
1559
1560/* Write the data of a PNG chunk started with png_write_chunk_start(). */
1561extern PNG_EXPORT(void,png_write_chunk_data) PNGARG((png_structp png_ptr,
1562 png_bytep data, png_size_t length));
1563
1564/* Finish a chunk started with png_write_chunk_start() (includes CRC). */
1565extern PNG_EXPORT(void,png_write_chunk_end) PNGARG((png_structp png_ptr));
1566
1567/* Allocate and initialize the info structure */
1568extern PNG_EXPORT(png_infop,png_create_info_struct)
1569 PNGARG((png_structp png_ptr));
1570
1571#if defined(PNG_1_0_X) || defined (PNG_1_2_X)
1572/* Initialize the info structure (old interface - DEPRECATED) */
1573extern PNG_EXPORT(void,png_info_init) PNGARG((png_infop info_ptr));
1574#undef png_info_init
1575#define png_info_init(info_ptr) png_info_init_3(&info_ptr,\
1576 png_sizeof(png_info));
1577#endif
1578
1579extern PNG_EXPORT(void,png_info_init_3) PNGARG((png_infopp info_ptr,
1580 png_size_t png_info_struct_size));
1581
1582/* Writes all the PNG information before the image. */
1583extern PNG_EXPORT(void,png_write_info_before_PLTE) PNGARG((png_structp png_ptr,
1584 png_infop info_ptr));
1585extern PNG_EXPORT(void,png_write_info) PNGARG((png_structp png_ptr,
1586 png_infop info_ptr));
1587
1588#ifndef PNG_NO_SEQUENTIAL_READ_SUPPORTED
1589/* read the information before the actual image data. */
1590extern PNG_EXPORT(void,png_read_info) PNGARG((png_structp png_ptr,
1591 png_infop info_ptr));
1592#endif
1593
1594#if defined(PNG_TIME_RFC1123_SUPPORTED)
1595extern PNG_EXPORT(png_charp,png_convert_to_rfc1123)
1596 PNGARG((png_structp png_ptr, png_timep ptime));
1597#endif
1598
1599#if !defined(_WIN32_WCE)
1600/* "time.h" functions are not supported on WindowsCE */
1601#if defined(PNG_WRITE_tIME_SUPPORTED)
1602/* convert from a struct tm to png_time */
1603extern PNG_EXPORT(void,png_convert_from_struct_tm) PNGARG((png_timep ptime,
1604 struct tm FAR * ttime));
1605
1606/* convert from time_t to png_time. Uses gmtime() */
1607extern PNG_EXPORT(void,png_convert_from_time_t) PNGARG((png_timep ptime,
1608 time_t ttime));
1609#endif /* PNG_WRITE_tIME_SUPPORTED */
1610#endif /* _WIN32_WCE */
1611
1612#if defined(PNG_READ_EXPAND_SUPPORTED)
1613/* Expand data to 24-bit RGB, or 8-bit grayscale, with alpha if available. */
1614extern PNG_EXPORT(void,png_set_expand) PNGARG((png_structp png_ptr));
1615#if !defined(PNG_1_0_X)
1616extern PNG_EXPORT(void,png_set_expand_gray_1_2_4_to_8) PNGARG((png_structp
1617 png_ptr));
1618#endif
1619extern PNG_EXPORT(void,png_set_palette_to_rgb) PNGARG((png_structp png_ptr));
1620extern PNG_EXPORT(void,png_set_tRNS_to_alpha) PNGARG((png_structp png_ptr));
1621#if defined(PNG_1_0_X) || defined (PNG_1_2_X)
1622/* Deprecated */
1623extern PNG_EXPORT(void,png_set_gray_1_2_4_to_8) PNGARG((png_structp png_ptr));
1624#endif
1625#endif
1626
1627#if defined(PNG_READ_BGR_SUPPORTED) || defined(PNG_WRITE_BGR_SUPPORTED)
1628/* Use blue, green, red order for pixels. */
1629extern PNG_EXPORT(void,png_set_bgr) PNGARG((png_structp png_ptr));
1630#endif
1631
1632#if defined(PNG_READ_GRAY_TO_RGB_SUPPORTED)
1633/* Expand the grayscale to 24-bit RGB if necessary. */
1634extern PNG_EXPORT(void,png_set_gray_to_rgb) PNGARG((png_structp png_ptr));
1635#endif
1636
1637#if defined(PNG_READ_RGB_TO_GRAY_SUPPORTED)
1638/* Reduce RGB to grayscale. */
1639#ifdef PNG_FLOATING_POINT_SUPPORTED
1640extern PNG_EXPORT(void,png_set_rgb_to_gray) PNGARG((png_structp png_ptr,
1641 int error_action, double red, double green ));
1642#endif
1643extern PNG_EXPORT(void,png_set_rgb_to_gray_fixed) PNGARG((png_structp png_ptr,
1644 int error_action, png_fixed_point red, png_fixed_point green ));
1645extern PNG_EXPORT(png_byte,png_get_rgb_to_gray_status) PNGARG((png_structp
1646 png_ptr));
1647#endif
1648
1649extern PNG_EXPORT(void,png_build_grayscale_palette) PNGARG((int bit_depth,
1650 png_colorp palette));
1651
1652#if defined(PNG_READ_STRIP_ALPHA_SUPPORTED)
1653extern PNG_EXPORT(void,png_set_strip_alpha) PNGARG((png_structp png_ptr));
1654#endif
1655
1656#if defined(PNG_READ_SWAP_ALPHA_SUPPORTED) || \
1657 defined(PNG_WRITE_SWAP_ALPHA_SUPPORTED)
1658extern PNG_EXPORT(void,png_set_swap_alpha) PNGARG((png_structp png_ptr));
1659#endif
1660
1661#if defined(PNG_READ_INVERT_ALPHA_SUPPORTED) || \
1662 defined(PNG_WRITE_INVERT_ALPHA_SUPPORTED)
1663extern PNG_EXPORT(void,png_set_invert_alpha) PNGARG((png_structp png_ptr));
1664#endif
1665
1666#if defined(PNG_READ_FILLER_SUPPORTED) || defined(PNG_WRITE_FILLER_SUPPORTED)
1667/* Add a filler byte to 8-bit Gray or 24-bit RGB images. */
1668extern PNG_EXPORT(void,png_set_filler) PNGARG((png_structp png_ptr,
1669 png_uint_32 filler, int flags));
1670/* The values of the PNG_FILLER_ defines should NOT be changed */
1671#define PNG_FILLER_BEFORE 0
1672#define PNG_FILLER_AFTER 1
1673/* Add an alpha byte to 8-bit Gray or 24-bit RGB images. */
1674#if !defined(PNG_1_0_X)
1675extern PNG_EXPORT(void,png_set_add_alpha) PNGARG((png_structp png_ptr,
1676 png_uint_32 filler, int flags));
1677#endif
1678#endif /* PNG_READ_FILLER_SUPPORTED || PNG_WRITE_FILLER_SUPPORTED */
1679
1680#if defined(PNG_READ_SWAP_SUPPORTED) || defined(PNG_WRITE_SWAP_SUPPORTED)
1681/* Swap bytes in 16-bit depth files. */
1682extern PNG_EXPORT(void,png_set_swap) PNGARG((png_structp png_ptr));
1683#endif
1684
1685#if defined(PNG_READ_PACK_SUPPORTED) || defined(PNG_WRITE_PACK_SUPPORTED)
1686/* Use 1 byte per pixel in 1, 2, or 4-bit depth files. */
1687extern PNG_EXPORT(void,png_set_packing) PNGARG((png_structp png_ptr));
1688#endif
1689
1690#if defined(PNG_READ_PACKSWAP_SUPPORTED) || defined(PNG_WRITE_PACKSWAP_SUPPORTED)
1691/* Swap packing order of pixels in bytes. */
1692extern PNG_EXPORT(void,png_set_packswap) PNGARG((png_structp png_ptr));
1693#endif
1694
1695#if defined(PNG_READ_SHIFT_SUPPORTED) || defined(PNG_WRITE_SHIFT_SUPPORTED)
1696/* Converts files to legal bit depths. */
1697extern PNG_EXPORT(void,png_set_shift) PNGARG((png_structp png_ptr,
1698 png_color_8p true_bits));
1699#endif
1700
1701#if defined(PNG_READ_INTERLACING_SUPPORTED) || \
1702 defined(PNG_WRITE_INTERLACING_SUPPORTED)
1703/* Have the code handle the interlacing. Returns the number of passes. */
1704extern PNG_EXPORT(int,png_set_interlace_handling) PNGARG((png_structp png_ptr));
1705#endif
1706
1707#if defined(PNG_READ_INVERT_SUPPORTED) || defined(PNG_WRITE_INVERT_SUPPORTED)
1708/* Invert monochrome files */
1709extern PNG_EXPORT(void,png_set_invert_mono) PNGARG((png_structp png_ptr));
1710#endif
1711
1712#if defined(PNG_READ_BACKGROUND_SUPPORTED)
1713/* Handle alpha and tRNS by replacing with a background color. */
1714#ifdef PNG_FLOATING_POINT_SUPPORTED
1715extern PNG_EXPORT(void,png_set_background) PNGARG((png_structp png_ptr,
1716 png_color_16p background_color, int background_gamma_code,
1717 int need_expand, double background_gamma));
1718#endif
1719#define PNG_BACKGROUND_GAMMA_UNKNOWN 0
1720#define PNG_BACKGROUND_GAMMA_SCREEN 1
1721#define PNG_BACKGROUND_GAMMA_FILE 2
1722#define PNG_BACKGROUND_GAMMA_UNIQUE 3
1723#endif
1724
1725#if defined(PNG_READ_16_TO_8_SUPPORTED)
1726/* strip the second byte of information from a 16-bit depth file. */
1727extern PNG_EXPORT(void,png_set_strip_16) PNGARG((png_structp png_ptr));
1728#endif
1729
1730#if defined(PNG_READ_DITHER_SUPPORTED)
1731/* Turn on dithering, and reduce the palette to the number of colors available. */
1732extern PNG_EXPORT(void,png_set_dither) PNGARG((png_structp png_ptr,
1733 png_colorp palette, int num_palette, int maximum_colors,
1734 png_uint_16p histogram, int full_dither));
1735#endif
1736
1737#if defined(PNG_READ_GAMMA_SUPPORTED)
1738/* Handle gamma correction. Screen_gamma=(display_exponent) */
1739#ifdef PNG_FLOATING_POINT_SUPPORTED
1740extern PNG_EXPORT(void,png_set_gamma) PNGARG((png_structp png_ptr,
1741 double screen_gamma, double default_file_gamma));
1742#endif
1743#endif
1744
1745#if defined(PNG_1_0_X) || defined (PNG_1_2_X)
1746#if defined(PNG_READ_EMPTY_PLTE_SUPPORTED) || \
1747 defined(PNG_WRITE_EMPTY_PLTE_SUPPORTED)
1748/* Permit or disallow empty PLTE (0: not permitted, 1: permitted) */
1749/* Deprecated and will be removed. Use png_permit_mng_features() instead. */
1750extern PNG_EXPORT(void,png_permit_empty_plte) PNGARG((png_structp png_ptr,
1751 int empty_plte_permitted));
1752#endif
1753#endif
1754
1755#if defined(PNG_WRITE_FLUSH_SUPPORTED)
1756/* Set how many lines between output flushes - 0 for no flushing */
1757extern PNG_EXPORT(void,png_set_flush) PNGARG((png_structp png_ptr, int nrows));
1758/* Flush the current PNG output buffer */
1759extern PNG_EXPORT(void,png_write_flush) PNGARG((png_structp png_ptr));
1760#endif
1761
1762/* optional update palette with requested transformations */
1763extern PNG_EXPORT(void,png_start_read_image) PNGARG((png_structp png_ptr));
1764
1765/* optional call to update the users info structure */
1766extern PNG_EXPORT(void,png_read_update_info) PNGARG((png_structp png_ptr,
1767 png_infop info_ptr));
1768
1769#ifndef PNG_NO_SEQUENTIAL_READ_SUPPORTED
1770/* read one or more rows of image data. */
1771extern PNG_EXPORT(void,png_read_rows) PNGARG((png_structp png_ptr,
1772 png_bytepp row, png_bytepp display_row, png_uint_32 num_rows));
1773#endif
1774
1775#ifndef PNG_NO_SEQUENTIAL_READ_SUPPORTED
1776/* read a row of data. */
1777extern PNG_EXPORT(void,png_read_row) PNGARG((png_structp png_ptr,
1778 png_bytep row,
1779 png_bytep display_row));
1780#endif
1781
1782#ifndef PNG_NO_SEQUENTIAL_READ_SUPPORTED
1783/* read the whole image into memory at once. */
1784extern PNG_EXPORT(void,png_read_image) PNGARG((png_structp png_ptr,
1785 png_bytepp image));
1786#endif
1787
1788/* write a row of image data */
1789extern PNG_EXPORT(void,png_write_row) PNGARG((png_structp png_ptr,
1790 png_bytep row));
1791
1792/* write a few rows of image data */
1793extern PNG_EXPORT(void,png_write_rows) PNGARG((png_structp png_ptr,
1794 png_bytepp row, png_uint_32 num_rows));
1795
1796/* write the image data */
1797extern PNG_EXPORT(void,png_write_image) PNGARG((png_structp png_ptr,
1798 png_bytepp image));
1799
1800/* writes the end of the PNG file. */
1801extern PNG_EXPORT(void,png_write_end) PNGARG((png_structp png_ptr,
1802 png_infop info_ptr));
1803
1804#ifndef PNG_NO_SEQUENTIAL_READ_SUPPORTED
1805/* read the end of the PNG file. */
1806extern PNG_EXPORT(void,png_read_end) PNGARG((png_structp png_ptr,
1807 png_infop info_ptr));
1808#endif
1809
1810/* free any memory associated with the png_info_struct */
1811extern PNG_EXPORT(void,png_destroy_info_struct) PNGARG((png_structp png_ptr,
1812 png_infopp info_ptr_ptr));
1813
1814/* free any memory associated with the png_struct and the png_info_structs */
1815extern PNG_EXPORT(void,png_destroy_read_struct) PNGARG((png_structpp
1816 png_ptr_ptr, png_infopp info_ptr_ptr, png_infopp end_info_ptr_ptr));
1817
1818/* free all memory used by the read (old method - NOT DLL EXPORTED) */
1819extern void png_read_destroy PNGARG((png_structp png_ptr, png_infop info_ptr,
1820 png_infop end_info_ptr));
1821
1822/* free any memory associated with the png_struct and the png_info_structs */
1823extern PNG_EXPORT(void,png_destroy_write_struct)
1824 PNGARG((png_structpp png_ptr_ptr, png_infopp info_ptr_ptr));
1825
1826/* free any memory used in png_ptr struct (old method - NOT DLL EXPORTED) */
1827extern void png_write_destroy PNGARG((png_structp png_ptr));
1828
1829/* set the libpng method of handling chunk CRC errors */
1830extern PNG_EXPORT(void,png_set_crc_action) PNGARG((png_structp png_ptr,
1831 int crit_action, int ancil_action));
1832
1833/* Values for png_set_crc_action() to say how to handle CRC errors in
1834 * ancillary and critical chunks, and whether to use the data contained
1835 * therein. Note that it is impossible to "discard" data in a critical
1836 * chunk. For versions prior to 0.90, the action was always error/quit,
1837 * whereas in version 0.90 and later, the action for CRC errors in ancillary
1838 * chunks is warn/discard. These values should NOT be changed.
1839 *
1840 * value action:critical action:ancillary
1841 */
1842#define PNG_CRC_DEFAULT 0 /* error/quit warn/discard data */
1843#define PNG_CRC_ERROR_QUIT 1 /* error/quit error/quit */
1844#define PNG_CRC_WARN_DISCARD 2 /* (INVALID) warn/discard data */
1845#define PNG_CRC_WARN_USE 3 /* warn/use data warn/use data */
1846#define PNG_CRC_QUIET_USE 4 /* quiet/use data quiet/use data */
1847#define PNG_CRC_NO_CHANGE 5 /* use current value use current value */
1848
1849/* These functions give the user control over the scan-line filtering in
1850 * libpng and the compression methods used by zlib. These functions are
1851 * mainly useful for testing, as the defaults should work with most users.
1852 * Those users who are tight on memory or want faster performance at the
1853 * expense of compression can modify them. See the compression library
1854 * header file (zlib.h) for an explination of the compression functions.
1855 */
1856
1857/* set the filtering method(s) used by libpng. Currently, the only valid
1858 * value for "method" is 0.
1859 */
1860extern PNG_EXPORT(void,png_set_filter) PNGARG((png_structp png_ptr, int method,
1861 int filters));
1862
1863/* Flags for png_set_filter() to say which filters to use. The flags
1864 * are chosen so that they don't conflict with real filter types
1865 * below, in case they are supplied instead of the #defined constants.
1866 * These values should NOT be changed.
1867 */
1868#define PNG_NO_FILTERS 0x00
1869#define PNG_FILTER_NONE 0x08
1870#define PNG_FILTER_SUB 0x10
1871#define PNG_FILTER_UP 0x20
1872#define PNG_FILTER_AVG 0x40
1873#define PNG_FILTER_PAETH 0x80
1874#define PNG_ALL_FILTERS (PNG_FILTER_NONE | PNG_FILTER_SUB | PNG_FILTER_UP | \
1875 PNG_FILTER_AVG | PNG_FILTER_PAETH)
1876
1877/* Filter values (not flags) - used in pngwrite.c, pngwutil.c for now.
1878 * These defines should NOT be changed.
1879 */
1880#define PNG_FILTER_VALUE_NONE 0
1881#define PNG_FILTER_VALUE_SUB 1
1882#define PNG_FILTER_VALUE_UP 2
1883#define PNG_FILTER_VALUE_AVG 3
1884#define PNG_FILTER_VALUE_PAETH 4
1885#define PNG_FILTER_VALUE_LAST 5
1886
1887#if defined(PNG_WRITE_WEIGHTED_FILTER_SUPPORTED) /* EXPERIMENTAL */
1888/* The "heuristic_method" is given by one of the PNG_FILTER_HEURISTIC_
1889 * defines, either the default (minimum-sum-of-absolute-differences), or
1890 * the experimental method (weighted-minimum-sum-of-absolute-differences).
1891 *
1892 * Weights are factors >= 1.0, indicating how important it is to keep the
1893 * filter type consistent between rows. Larger numbers mean the current
1894 * filter is that many times as likely to be the same as the "num_weights"
1895 * previous filters. This is cumulative for each previous row with a weight.
1896 * There needs to be "num_weights" values in "filter_weights", or it can be
1897 * NULL if the weights aren't being specified. Weights have no influence on
1898 * the selection of the first row filter. Well chosen weights can (in theory)
1899 * improve the compression for a given image.
1900 *
1901 * Costs are factors >= 1.0 indicating the relative decoding costs of a
1902 * filter type. Higher costs indicate more decoding expense, and are
1903 * therefore less likely to be selected over a filter with lower computational
1904 * costs. There needs to be a value in "filter_costs" for each valid filter
1905 * type (given by PNG_FILTER_VALUE_LAST), or it can be NULL if you aren't
1906 * setting the costs. Costs try to improve the speed of decompression without
1907 * unduly increasing the compressed image size.
1908 *
1909 * A negative weight or cost indicates the default value is to be used, and
1910 * values in the range [0.0, 1.0) indicate the value is to remain unchanged.
1911 * The default values for both weights and costs are currently 1.0, but may
1912 * change if good general weighting/cost heuristics can be found. If both
1913 * the weights and costs are set to 1.0, this degenerates the WEIGHTED method
1914 * to the UNWEIGHTED method, but with added encoding time/computation.
1915 */
1916#ifdef PNG_FLOATING_POINT_SUPPORTED
1917extern PNG_EXPORT(void,png_set_filter_heuristics) PNGARG((png_structp png_ptr,
1918 int heuristic_method, int num_weights, png_doublep filter_weights,
1919 png_doublep filter_costs));
1920#endif
1921#endif /* PNG_WRITE_WEIGHTED_FILTER_SUPPORTED */
1922
1923/* Heuristic used for row filter selection. These defines should NOT be
1924 * changed.
1925 */
1926#define PNG_FILTER_HEURISTIC_DEFAULT 0 /* Currently "UNWEIGHTED" */
1927#define PNG_FILTER_HEURISTIC_UNWEIGHTED 1 /* Used by libpng < 0.95 */
1928#define PNG_FILTER_HEURISTIC_WEIGHTED 2 /* Experimental feature */
1929#define PNG_FILTER_HEURISTIC_LAST 3 /* Not a valid value */
1930
1931/* Set the library compression level. Currently, valid values range from
1932 * 0 - 9, corresponding directly to the zlib compression levels 0 - 9
1933 * (0 - no compression, 9 - "maximal" compression). Note that tests have
1934 * shown that zlib compression levels 3-6 usually perform as well as level 9
1935 * for PNG images, and do considerably fewer caclulations. In the future,
1936 * these values may not correspond directly to the zlib compression levels.
1937 */
1938extern PNG_EXPORT(void,png_set_compression_level) PNGARG((png_structp png_ptr,
1939 int level));
1940
1941extern PNG_EXPORT(void,png_set_compression_mem_level)
1942 PNGARG((png_structp png_ptr, int mem_level));
1943
1944extern PNG_EXPORT(void,png_set_compression_strategy)
1945 PNGARG((png_structp png_ptr, int strategy));
1946
1947extern PNG_EXPORT(void,png_set_compression_window_bits)
1948 PNGARG((png_structp png_ptr, int window_bits));
1949
1950extern PNG_EXPORT(void,png_set_compression_method) PNGARG((png_structp png_ptr,
1951 int method));
1952
1953/* These next functions are called for input/output, memory, and error
1954 * handling. They are in the file pngrio.c, pngwio.c, and pngerror.c,
1955 * and call standard C I/O routines such as fread(), fwrite(), and
1956 * fprintf(). These functions can be made to use other I/O routines
1957 * at run time for those applications that need to handle I/O in a
1958 * different manner by calling png_set_???_fn(). See libpng.txt for
1959 * more information.
1960 */
1961
1962#if !defined(PNG_NO_STDIO)
1963/* Initialize the input/output for the PNG file to the default functions. */
1964extern PNG_EXPORT(void,png_init_io) PNGARG((png_structp png_ptr, png_FILE_p fp));
1965#endif
1966
1967/* Replace the (error and abort), and warning functions with user
1968 * supplied functions. If no messages are to be printed you must still
1969 * write and use replacement functions. The replacement error_fn should
1970 * still do a longjmp to the last setjmp location if you are using this
1971 * method of error handling. If error_fn or warning_fn is NULL, the
1972 * default function will be used.
1973 */
1974
1975extern PNG_EXPORT(void,png_set_error_fn) PNGARG((png_structp png_ptr,
1976 png_voidp error_ptr, png_error_ptr error_fn, png_error_ptr warning_fn));
1977
1978/* Return the user pointer associated with the error functions */
1979extern PNG_EXPORT(png_voidp,png_get_error_ptr) PNGARG((png_structp png_ptr));
1980
1981/* Replace the default data output functions with a user supplied one(s).
1982 * If buffered output is not used, then output_flush_fn can be set to NULL.
1983 * If PNG_WRITE_FLUSH_SUPPORTED is not defined at libpng compile time
1984 * output_flush_fn will be ignored (and thus can be NULL).
1985 */
1986extern PNG_EXPORT(void,png_set_write_fn) PNGARG((png_structp png_ptr,
1987 png_voidp io_ptr, png_rw_ptr write_data_fn, png_flush_ptr output_flush_fn));
1988
1989/* Replace the default data input function with a user supplied one. */
1990extern PNG_EXPORT(void,png_set_read_fn) PNGARG((png_structp png_ptr,
1991 png_voidp io_ptr, png_rw_ptr read_data_fn));
1992
1993/* Return the user pointer associated with the I/O functions */
1994extern PNG_EXPORT(png_voidp,png_get_io_ptr) PNGARG((png_structp png_ptr));
1995
1996extern PNG_EXPORT(void,png_set_read_status_fn) PNGARG((png_structp png_ptr,
1997 png_read_status_ptr read_row_fn));
1998
1999extern PNG_EXPORT(void,png_set_write_status_fn) PNGARG((png_structp png_ptr,
2000 png_write_status_ptr write_row_fn));
2001
2002#ifdef PNG_USER_MEM_SUPPORTED
2003/* Replace the default memory allocation functions with user supplied one(s). */
2004extern PNG_EXPORT(void,png_set_mem_fn) PNGARG((png_structp png_ptr,
2005 png_voidp mem_ptr, png_malloc_ptr malloc_fn, png_free_ptr free_fn));
2006/* Return the user pointer associated with the memory functions */
2007extern PNG_EXPORT(png_voidp,png_get_mem_ptr) PNGARG((png_structp png_ptr));
2008#endif
2009
2010#if defined(PNG_READ_USER_TRANSFORM_SUPPORTED) || \
2011 defined(PNG_LEGACY_SUPPORTED)
2012extern PNG_EXPORT(void,png_set_read_user_transform_fn) PNGARG((png_structp
2013 png_ptr, png_user_transform_ptr read_user_transform_fn));
2014#endif
2015
2016#if defined(PNG_WRITE_USER_TRANSFORM_SUPPORTED) || \
2017 defined(PNG_LEGACY_SUPPORTED)
2018extern PNG_EXPORT(void,png_set_write_user_transform_fn) PNGARG((png_structp
2019 png_ptr, png_user_transform_ptr write_user_transform_fn));
2020#endif
2021
2022#if defined(PNG_READ_USER_TRANSFORM_SUPPORTED) || \
2023 defined(PNG_WRITE_USER_TRANSFORM_SUPPORTED) || \
2024 defined(PNG_LEGACY_SUPPORTED)
2025extern PNG_EXPORT(void,png_set_user_transform_info) PNGARG((png_structp
2026 png_ptr, png_voidp user_transform_ptr, int user_transform_depth,
2027 int user_transform_channels));
2028/* Return the user pointer associated with the user transform functions */
2029extern PNG_EXPORT(png_voidp,png_get_user_transform_ptr)
2030 PNGARG((png_structp png_ptr));
2031#endif
2032
2033#ifdef PNG_USER_CHUNKS_SUPPORTED
2034extern PNG_EXPORT(void,png_set_read_user_chunk_fn) PNGARG((png_structp png_ptr,
2035 png_voidp user_chunk_ptr, png_user_chunk_ptr read_user_chunk_fn));
2036extern PNG_EXPORT(png_voidp,png_get_user_chunk_ptr) PNGARG((png_structp
2037 png_ptr));
2038#endif
2039
2040#ifdef PNG_PROGRESSIVE_READ_SUPPORTED
2041/* Sets the function callbacks for the push reader, and a pointer to a
2042 * user-defined structure available to the callback functions.
2043 */
2044extern PNG_EXPORT(void,png_set_progressive_read_fn) PNGARG((png_structp png_ptr,
2045 png_voidp progressive_ptr,
2046 png_progressive_info_ptr info_fn, png_progressive_row_ptr row_fn,
2047 png_progressive_end_ptr end_fn));
2048
2049/* returns the user pointer associated with the push read functions */
2050extern PNG_EXPORT(png_voidp,png_get_progressive_ptr)
2051 PNGARG((png_structp png_ptr));
2052
2053/* function to be called when data becomes available */
2054extern PNG_EXPORT(void,png_process_data) PNGARG((png_structp png_ptr,
2055 png_infop info_ptr, png_bytep buffer, png_size_t buffer_size));
2056
2057/* function that combines rows. Not very much different than the
2058 * png_combine_row() call. Is this even used?????
2059 */
2060extern PNG_EXPORT(void,png_progressive_combine_row) PNGARG((png_structp png_ptr,
2061 png_bytep old_row, png_bytep new_row));
2062#endif /* PNG_PROGRESSIVE_READ_SUPPORTED */
2063
2064extern PNG_EXPORT(png_voidp,png_malloc) PNGARG((png_structp png_ptr,
2065 png_uint_32 size));
2066
2067#if defined(PNG_1_0_X)
2068# define png_malloc_warn png_malloc
2069#else
2070/* Added at libpng version 1.2.4 */
2071extern PNG_EXPORT(png_voidp,png_malloc_warn) PNGARG((png_structp png_ptr,
2072 png_uint_32 size));
2073#endif
2074
2075/* frees a pointer allocated by png_malloc() */
2076extern PNG_EXPORT(void,png_free) PNGARG((png_structp png_ptr, png_voidp ptr));
2077
2078#if defined(PNG_1_0_X)
2079/* Function to allocate memory for zlib. */
2080extern PNG_EXPORT(voidpf,png_zalloc) PNGARG((voidpf png_ptr, uInt items,
2081 uInt size));
2082
2083/* Function to free memory for zlib */
2084extern PNG_EXPORT(void,png_zfree) PNGARG((voidpf png_ptr, voidpf ptr));
2085#endif
2086
2087/* Free data that was allocated internally */
2088extern PNG_EXPORT(void,png_free_data) PNGARG((png_structp png_ptr,
2089 png_infop info_ptr, png_uint_32 free_me, int num));
2090#ifdef PNG_FREE_ME_SUPPORTED
2091/* Reassign responsibility for freeing existing data, whether allocated
2092 * by libpng or by the application */
2093extern PNG_EXPORT(void,png_data_freer) PNGARG((png_structp png_ptr,
2094 png_infop info_ptr, int freer, png_uint_32 mask));
2095#endif
2096/* assignments for png_data_freer */
2097#define PNG_DESTROY_WILL_FREE_DATA 1
2098#define PNG_SET_WILL_FREE_DATA 1
2099#define PNG_USER_WILL_FREE_DATA 2
2100/* Flags for png_ptr->free_me and info_ptr->free_me */
2101#define PNG_FREE_HIST 0x0008
2102#define PNG_FREE_ICCP 0x0010
2103#define PNG_FREE_SPLT 0x0020
2104#define PNG_FREE_ROWS 0x0040
2105#define PNG_FREE_PCAL 0x0080
2106#define PNG_FREE_SCAL 0x0100
2107#define PNG_FREE_UNKN 0x0200
2108#define PNG_FREE_LIST 0x0400
2109#define PNG_FREE_PLTE 0x1000
2110#define PNG_FREE_TRNS 0x2000
2111#define PNG_FREE_TEXT 0x4000
2112#define PNG_FREE_ALL 0x7fff
2113#define PNG_FREE_MUL 0x4220 /* PNG_FREE_SPLT|PNG_FREE_TEXT|PNG_FREE_UNKN */
2114
2115#ifdef PNG_USER_MEM_SUPPORTED
2116extern PNG_EXPORT(png_voidp,png_malloc_default) PNGARG((png_structp png_ptr,
2117 png_uint_32 size));
2118extern PNG_EXPORT(void,png_free_default) PNGARG((png_structp png_ptr,
2119 png_voidp ptr));
2120#endif
2121
2122extern PNG_EXPORT(png_voidp,png_memcpy_check) PNGARG((png_structp png_ptr,
2123 png_voidp s1, png_voidp s2, png_uint_32 size));
2124
2125extern PNG_EXPORT(png_voidp,png_memset_check) PNGARG((png_structp png_ptr,
2126 png_voidp s1, int value, png_uint_32 size));
2127
2128#if defined(USE_FAR_KEYWORD) /* memory model conversion function */
2129extern void *png_far_to_near PNGARG((png_structp png_ptr,png_voidp ptr,
2130 int check));
2131#endif /* USE_FAR_KEYWORD */
2132
2133#ifndef PNG_NO_ERROR_TEXT
2134/* Fatal error in PNG image of libpng - can't continue */
2135extern PNG_EXPORT(void,png_error) PNGARG((png_structp png_ptr,
2136 png_const_charp error_message));
2137
2138/* The same, but the chunk name is prepended to the error string. */
2139extern PNG_EXPORT(void,png_chunk_error) PNGARG((png_structp png_ptr,
2140 png_const_charp error_message));
2141#else
2142/* Fatal error in PNG image of libpng - can't continue */
2143extern PNG_EXPORT(void,png_err) PNGARG((png_structp png_ptr));
2144#endif
2145
2146#ifndef PNG_NO_WARNINGS
2147/* Non-fatal error in libpng. Can continue, but may have a problem. */
2148extern PNG_EXPORT(void,png_warning) PNGARG((png_structp png_ptr,
2149 png_const_charp warning_message));
2150
2151#ifdef PNG_READ_SUPPORTED
2152/* Non-fatal error in libpng, chunk name is prepended to message. */
2153extern PNG_EXPORT(void,png_chunk_warning) PNGARG((png_structp png_ptr,
2154 png_const_charp warning_message));
2155#endif /* PNG_READ_SUPPORTED */
2156#endif /* PNG_NO_WARNINGS */
2157
2158/* The png_set_<chunk> functions are for storing values in the png_info_struct.
2159 * Similarly, the png_get_<chunk> calls are used to read values from the
2160 * png_info_struct, either storing the parameters in the passed variables, or
2161 * setting pointers into the png_info_struct where the data is stored. The
2162 * png_get_<chunk> functions return a non-zero value if the data was available
2163 * in info_ptr, or return zero and do not change any of the parameters if the
2164 * data was not available.
2165 *
2166 * These functions should be used instead of directly accessing png_info
2167 * to avoid problems with future changes in the size and internal layout of
2168 * png_info_struct.
2169 */
2170/* Returns "flag" if chunk data is valid in info_ptr. */
2171extern PNG_EXPORT(png_uint_32,png_get_valid) PNGARG((png_structp png_ptr,
2172png_infop info_ptr, png_uint_32 flag));
2173
2174/* Returns number of bytes needed to hold a transformed row. */
2175extern PNG_EXPORT(png_uint_32,png_get_rowbytes) PNGARG((png_structp png_ptr,
2176png_infop info_ptr));
2177
2178#if defined(PNG_INFO_IMAGE_SUPPORTED)
2179/* Returns row_pointers, which is an array of pointers to scanlines that was
2180returned from png_read_png(). */
2181extern PNG_EXPORT(png_bytepp,png_get_rows) PNGARG((png_structp png_ptr,
2182png_infop info_ptr));
2183/* Set row_pointers, which is an array of pointers to scanlines for use
2184by png_write_png(). */
2185extern PNG_EXPORT(void,png_set_rows) PNGARG((png_structp png_ptr,
2186 png_infop info_ptr, png_bytepp row_pointers));
2187#endif
2188
2189/* Returns number of color channels in image. */
2190extern PNG_EXPORT(png_byte,png_get_channels) PNGARG((png_structp png_ptr,
2191png_infop info_ptr));
2192
2193#ifdef PNG_EASY_ACCESS_SUPPORTED
2194/* Returns image width in pixels. */
2195extern PNG_EXPORT(png_uint_32, png_get_image_width) PNGARG((png_structp
2196png_ptr, png_infop info_ptr));
2197
2198/* Returns image height in pixels. */
2199extern PNG_EXPORT(png_uint_32, png_get_image_height) PNGARG((png_structp
2200png_ptr, png_infop info_ptr));
2201
2202/* Returns image bit_depth. */
2203extern PNG_EXPORT(png_byte, png_get_bit_depth) PNGARG((png_structp
2204png_ptr, png_infop info_ptr));
2205
2206/* Returns image color_type. */
2207extern PNG_EXPORT(png_byte, png_get_color_type) PNGARG((png_structp
2208png_ptr, png_infop info_ptr));
2209
2210/* Returns image filter_type. */
2211extern PNG_EXPORT(png_byte, png_get_filter_type) PNGARG((png_structp
2212png_ptr, png_infop info_ptr));
2213
2214/* Returns image interlace_type. */
2215extern PNG_EXPORT(png_byte, png_get_interlace_type) PNGARG((png_structp
2216png_ptr, png_infop info_ptr));
2217
2218/* Returns image compression_type. */
2219extern PNG_EXPORT(png_byte, png_get_compression_type) PNGARG((png_structp
2220png_ptr, png_infop info_ptr));
2221
2222/* Returns image resolution in pixels per meter, from pHYs chunk data. */
2223extern PNG_EXPORT(png_uint_32, png_get_pixels_per_meter) PNGARG((png_structp
2224png_ptr, png_infop info_ptr));
2225extern PNG_EXPORT(png_uint_32, png_get_x_pixels_per_meter) PNGARG((png_structp
2226png_ptr, png_infop info_ptr));
2227extern PNG_EXPORT(png_uint_32, png_get_y_pixels_per_meter) PNGARG((png_structp
2228png_ptr, png_infop info_ptr));
2229
2230/* Returns pixel aspect ratio, computed from pHYs chunk data. */
2231#ifdef PNG_FLOATING_POINT_SUPPORTED
2232extern PNG_EXPORT(float, png_get_pixel_aspect_ratio) PNGARG((png_structp
2233png_ptr, png_infop info_ptr));
2234#endif
2235
2236/* Returns image x, y offset in pixels or microns, from oFFs chunk data. */
2237extern PNG_EXPORT(png_int_32, png_get_x_offset_pixels) PNGARG((png_structp
2238png_ptr, png_infop info_ptr));
2239extern PNG_EXPORT(png_int_32, png_get_y_offset_pixels) PNGARG((png_structp
2240png_ptr, png_infop info_ptr));
2241extern PNG_EXPORT(png_int_32, png_get_x_offset_microns) PNGARG((png_structp
2242png_ptr, png_infop info_ptr));
2243extern PNG_EXPORT(png_int_32, png_get_y_offset_microns) PNGARG((png_structp
2244png_ptr, png_infop info_ptr));
2245
2246#endif /* PNG_EASY_ACCESS_SUPPORTED */
2247
2248/* Returns pointer to signature string read from PNG header */
2249extern PNG_EXPORT(png_bytep,png_get_signature) PNGARG((png_structp png_ptr,
2250png_infop info_ptr));
2251
2252#if defined(PNG_bKGD_SUPPORTED)
2253extern PNG_EXPORT(png_uint_32,png_get_bKGD) PNGARG((png_structp png_ptr,
2254 png_infop info_ptr, png_color_16p *background));
2255#endif
2256
2257#if defined(PNG_bKGD_SUPPORTED)
2258extern PNG_EXPORT(void,png_set_bKGD) PNGARG((png_structp png_ptr,
2259 png_infop info_ptr, png_color_16p background));
2260#endif
2261
2262#if defined(PNG_cHRM_SUPPORTED)
2263#ifdef PNG_FLOATING_POINT_SUPPORTED
2264extern PNG_EXPORT(png_uint_32,png_get_cHRM) PNGARG((png_structp png_ptr,
2265 png_infop info_ptr, double *white_x, double *white_y, double *red_x,
2266 double *red_y, double *green_x, double *green_y, double *blue_x,
2267 double *blue_y));
2268#endif
2269#ifdef PNG_FIXED_POINT_SUPPORTED
2270extern PNG_EXPORT(png_uint_32,png_get_cHRM_fixed) PNGARG((png_structp png_ptr,
2271 png_infop info_ptr, png_fixed_point *int_white_x, png_fixed_point
2272 *int_white_y, png_fixed_point *int_red_x, png_fixed_point *int_red_y,
2273 png_fixed_point *int_green_x, png_fixed_point *int_green_y, png_fixed_point
2274 *int_blue_x, png_fixed_point *int_blue_y));
2275#endif
2276#endif
2277
2278#if defined(PNG_cHRM_SUPPORTED)
2279#ifdef PNG_FLOATING_POINT_SUPPORTED
2280extern PNG_EXPORT(void,png_set_cHRM) PNGARG((png_structp png_ptr,
2281 png_infop info_ptr, double white_x, double white_y, double red_x,
2282 double red_y, double green_x, double green_y, double blue_x, double blue_y));
2283#endif
2284#ifdef PNG_FIXED_POINT_SUPPORTED
2285extern PNG_EXPORT(void,png_set_cHRM_fixed) PNGARG((png_structp png_ptr,
2286 png_infop info_ptr, png_fixed_point int_white_x, png_fixed_point int_white_y,
2287 png_fixed_point int_red_x, png_fixed_point int_red_y, png_fixed_point
2288 int_green_x, png_fixed_point int_green_y, png_fixed_point int_blue_x,
2289 png_fixed_point int_blue_y));
2290#endif
2291#endif
2292
2293#if defined(PNG_gAMA_SUPPORTED)
2294#ifdef PNG_FLOATING_POINT_SUPPORTED
2295extern PNG_EXPORT(png_uint_32,png_get_gAMA) PNGARG((png_structp png_ptr,
2296 png_infop info_ptr, double *file_gamma));
2297#endif
2298extern PNG_EXPORT(png_uint_32,png_get_gAMA_fixed) PNGARG((png_structp png_ptr,
2299 png_infop info_ptr, png_fixed_point *int_file_gamma));
2300#endif
2301
2302#if defined(PNG_gAMA_SUPPORTED)
2303#ifdef PNG_FLOATING_POINT_SUPPORTED
2304extern PNG_EXPORT(void,png_set_gAMA) PNGARG((png_structp png_ptr,
2305 png_infop info_ptr, double file_gamma));
2306#endif
2307extern PNG_EXPORT(void,png_set_gAMA_fixed) PNGARG((png_structp png_ptr,
2308 png_infop info_ptr, png_fixed_point int_file_gamma));
2309#endif
2310
2311#if defined(PNG_hIST_SUPPORTED)
2312extern PNG_EXPORT(png_uint_32,png_get_hIST) PNGARG((png_structp png_ptr,
2313 png_infop info_ptr, png_uint_16p *hist));
2314#endif
2315
2316#if defined(PNG_hIST_SUPPORTED)
2317extern PNG_EXPORT(void,png_set_hIST) PNGARG((png_structp png_ptr,
2318 png_infop info_ptr, png_uint_16p hist));
2319#endif
2320
2321extern PNG_EXPORT(png_uint_32,png_get_IHDR) PNGARG((png_structp png_ptr,
2322 png_infop info_ptr, png_uint_32 *width, png_uint_32 *height,
2323 int *bit_depth, int *color_type, int *interlace_method,
2324 int *compression_method, int *filter_method));
2325
2326extern PNG_EXPORT(void,png_set_IHDR) PNGARG((png_structp png_ptr,
2327 png_infop info_ptr, png_uint_32 width, png_uint_32 height, int bit_depth,
2328 int color_type, int interlace_method, int compression_method,
2329 int filter_method));
2330
2331#if defined(PNG_oFFs_SUPPORTED)
2332extern PNG_EXPORT(png_uint_32,png_get_oFFs) PNGARG((png_structp png_ptr,
2333 png_infop info_ptr, png_int_32 *offset_x, png_int_32 *offset_y,
2334 int *unit_type));
2335#endif
2336
2337#if defined(PNG_oFFs_SUPPORTED)
2338extern PNG_EXPORT(void,png_set_oFFs) PNGARG((png_structp png_ptr,
2339 png_infop info_ptr, png_int_32 offset_x, png_int_32 offset_y,
2340 int unit_type));
2341#endif
2342
2343#if defined(PNG_pCAL_SUPPORTED)
2344extern PNG_EXPORT(png_uint_32,png_get_pCAL) PNGARG((png_structp png_ptr,
2345 png_infop info_ptr, png_charp *purpose, png_int_32 *X0, png_int_32 *X1,
2346 int *type, int *nparams, png_charp *units, png_charpp *params));
2347#endif
2348
2349#if defined(PNG_pCAL_SUPPORTED)
2350extern PNG_EXPORT(void,png_set_pCAL) PNGARG((png_structp png_ptr,
2351 png_infop info_ptr, png_charp purpose, png_int_32 X0, png_int_32 X1,
2352 int type, int nparams, png_charp units, png_charpp params));
2353#endif
2354
2355#if defined(PNG_pHYs_SUPPORTED)
2356extern PNG_EXPORT(png_uint_32,png_get_pHYs) PNGARG((png_structp png_ptr,
2357 png_infop info_ptr, png_uint_32 *res_x, png_uint_32 *res_y, int *unit_type));
2358#endif
2359
2360#if defined(PNG_pHYs_SUPPORTED)
2361extern PNG_EXPORT(void,png_set_pHYs) PNGARG((png_structp png_ptr,
2362 png_infop info_ptr, png_uint_32 res_x, png_uint_32 res_y, int unit_type));
2363#endif
2364
2365extern PNG_EXPORT(png_uint_32,png_get_PLTE) PNGARG((png_structp png_ptr,
2366 png_infop info_ptr, png_colorp *palette, int *num_palette));
2367
2368extern PNG_EXPORT(void,png_set_PLTE) PNGARG((png_structp png_ptr,
2369 png_infop info_ptr, png_colorp palette, int num_palette));
2370
2371#if defined(PNG_sBIT_SUPPORTED)
2372extern PNG_EXPORT(png_uint_32,png_get_sBIT) PNGARG((png_structp png_ptr,
2373 png_infop info_ptr, png_color_8p *sig_bit));
2374#endif
2375
2376#if defined(PNG_sBIT_SUPPORTED)
2377extern PNG_EXPORT(void,png_set_sBIT) PNGARG((png_structp png_ptr,
2378 png_infop info_ptr, png_color_8p sig_bit));
2379#endif
2380
2381#if defined(PNG_sRGB_SUPPORTED)
2382extern PNG_EXPORT(png_uint_32,png_get_sRGB) PNGARG((png_structp png_ptr,
2383 png_infop info_ptr, int *intent));
2384#endif
2385
2386#if defined(PNG_sRGB_SUPPORTED)
2387extern PNG_EXPORT(void,png_set_sRGB) PNGARG((png_structp png_ptr,
2388 png_infop info_ptr, int intent));
2389extern PNG_EXPORT(void,png_set_sRGB_gAMA_and_cHRM) PNGARG((png_structp png_ptr,
2390 png_infop info_ptr, int intent));
2391#endif
2392
2393#if defined(PNG_iCCP_SUPPORTED)
2394extern PNG_EXPORT(png_uint_32,png_get_iCCP) PNGARG((png_structp png_ptr,
2395 png_infop info_ptr, png_charpp name, int *compression_type,
2396 png_charpp profile, png_uint_32 *proflen));
2397 /* Note to maintainer: profile should be png_bytepp */
2398#endif
2399
2400#if defined(PNG_iCCP_SUPPORTED)
2401extern PNG_EXPORT(void,png_set_iCCP) PNGARG((png_structp png_ptr,
2402 png_infop info_ptr, png_charp name, int compression_type,
2403 png_charp profile, png_uint_32 proflen));
2404 /* Note to maintainer: profile should be png_bytep */
2405#endif
2406
2407#if defined(PNG_sPLT_SUPPORTED)
2408extern PNG_EXPORT(png_uint_32,png_get_sPLT) PNGARG((png_structp png_ptr,
2409 png_infop info_ptr, png_sPLT_tpp entries));
2410#endif
2411
2412#if defined(PNG_sPLT_SUPPORTED)
2413extern PNG_EXPORT(void,png_set_sPLT) PNGARG((png_structp png_ptr,
2414 png_infop info_ptr, png_sPLT_tp entries, int nentries));
2415#endif
2416
2417#if defined(PNG_TEXT_SUPPORTED)
2418/* png_get_text also returns the number of text chunks in *num_text */
2419extern PNG_EXPORT(png_uint_32,png_get_text) PNGARG((png_structp png_ptr,
2420 png_infop info_ptr, png_textp *text_ptr, int *num_text));
2421#endif
2422
2423/*
2424 * Note while png_set_text() will accept a structure whose text,
2425 * language, and translated keywords are NULL pointers, the structure
2426 * returned by png_get_text will always contain regular
2427 * zero-terminated C strings. They might be empty strings but
2428 * they will never be NULL pointers.
2429 */
2430
2431#if defined(PNG_TEXT_SUPPORTED)
2432extern PNG_EXPORT(void,png_set_text) PNGARG((png_structp png_ptr,
2433 png_infop info_ptr, png_textp text_ptr, int num_text));
2434#endif
2435
2436#if defined(PNG_tIME_SUPPORTED)
2437extern PNG_EXPORT(png_uint_32,png_get_tIME) PNGARG((png_structp png_ptr,
2438 png_infop info_ptr, png_timep *mod_time));
2439#endif
2440
2441#if defined(PNG_tIME_SUPPORTED)
2442extern PNG_EXPORT(void,png_set_tIME) PNGARG((png_structp png_ptr,
2443 png_infop info_ptr, png_timep mod_time));
2444#endif
2445
2446#if defined(PNG_tRNS_SUPPORTED)
2447extern PNG_EXPORT(png_uint_32,png_get_tRNS) PNGARG((png_structp png_ptr,
2448 png_infop info_ptr, png_bytep *trans, int *num_trans,
2449 png_color_16p *trans_values));
2450#endif
2451
2452#if defined(PNG_tRNS_SUPPORTED)
2453extern PNG_EXPORT(void,png_set_tRNS) PNGARG((png_structp png_ptr,
2454 png_infop info_ptr, png_bytep trans, int num_trans,
2455 png_color_16p trans_values));
2456#endif
2457
2458#if defined(PNG_tRNS_SUPPORTED)
2459#endif
2460
2461#if defined(PNG_sCAL_SUPPORTED)
2462#ifdef PNG_FLOATING_POINT_SUPPORTED
2463extern PNG_EXPORT(png_uint_32,png_get_sCAL) PNGARG((png_structp png_ptr,
2464 png_infop info_ptr, int *unit, double *width, double *height));
2465#else
2466#ifdef PNG_FIXED_POINT_SUPPORTED
2467extern PNG_EXPORT(png_uint_32,png_get_sCAL_s) PNGARG((png_structp png_ptr,
2468 png_infop info_ptr, int *unit, png_charpp swidth, png_charpp sheight));
2469#endif
2470#endif
2471#endif /* PNG_sCAL_SUPPORTED */
2472
2473#if defined(PNG_sCAL_SUPPORTED)
2474#ifdef PNG_FLOATING_POINT_SUPPORTED
2475extern PNG_EXPORT(void,png_set_sCAL) PNGARG((png_structp png_ptr,
2476 png_infop info_ptr, int unit, double width, double height));
2477#else
2478#ifdef PNG_FIXED_POINT_SUPPORTED
2479extern PNG_EXPORT(void,png_set_sCAL_s) PNGARG((png_structp png_ptr,
2480 png_infop info_ptr, int unit, png_charp swidth, png_charp sheight));
2481#endif
2482#endif
2483#endif /* PNG_sCAL_SUPPORTED || PNG_WRITE_sCAL_SUPPORTED */
2484
2485#if defined(PNG_UNKNOWN_CHUNKS_SUPPORTED)
2486/* provide a list of chunks and how they are to be handled, if the built-in
2487 handling or default unknown chunk handling is not desired. Any chunks not
2488 listed will be handled in the default manner. The IHDR and IEND chunks
2489 must not be listed.
2490 keep = 0: follow default behaviour
2491 = 1: do not keep
2492 = 2: keep only if safe-to-copy
2493 = 3: keep even if unsafe-to-copy
2494*/
2495extern PNG_EXPORT(void, png_set_keep_unknown_chunks) PNGARG((png_structp
2496 png_ptr, int keep, png_bytep chunk_list, int num_chunks));
2497extern PNG_EXPORT(void, png_set_unknown_chunks) PNGARG((png_structp png_ptr,
2498 png_infop info_ptr, png_unknown_chunkp unknowns, int num_unknowns));
2499extern PNG_EXPORT(void, png_set_unknown_chunk_location)
2500 PNGARG((png_structp png_ptr, png_infop info_ptr, int chunk, int location));
2501extern PNG_EXPORT(png_uint_32,png_get_unknown_chunks) PNGARG((png_structp
2502 png_ptr, png_infop info_ptr, png_unknown_chunkpp entries));
2503#endif
2504#ifdef PNG_HANDLE_AS_UNKNOWN_SUPPORTED
2505PNG_EXPORT(int,png_handle_as_unknown) PNGARG((png_structp png_ptr, png_bytep
2506 chunk_name));
2507#endif
2508
2509/* Png_free_data() will turn off the "valid" flag for anything it frees.
2510 If you need to turn it off for a chunk that your application has freed,
2511 you can use png_set_invalid(png_ptr, info_ptr, PNG_INFO_CHNK); */
2512extern PNG_EXPORT(void, png_set_invalid) PNGARG((png_structp png_ptr,
2513 png_infop info_ptr, int mask));
2514
2515#if defined(PNG_INFO_IMAGE_SUPPORTED)
2516/* The "params" pointer is currently not used and is for future expansion. */
2517extern PNG_EXPORT(void, png_read_png) PNGARG((png_structp png_ptr,
2518 png_infop info_ptr,
2519 int transforms,
2520 png_voidp params));
2521extern PNG_EXPORT(void, png_write_png) PNGARG((png_structp png_ptr,
2522 png_infop info_ptr,
2523 int transforms,
2524 png_voidp params));
2525#endif
2526
2527/* Define PNG_DEBUG at compile time for debugging information. Higher
2528 * numbers for PNG_DEBUG mean more debugging information. This has
2529 * only been added since version 0.95 so it is not implemented throughout
2530 * libpng yet, but more support will be added as needed.
2531 */
2532#ifdef PNG_DEBUG
2533#if (PNG_DEBUG > 0)
2534#if !defined(PNG_DEBUG_FILE) && defined(_MSC_VER)
2535#include <crtdbg.h>
2536#if (PNG_DEBUG > 1)
2537#ifndef _DEBUG
2538# define _DEBUG
2539#endif
2540#ifndef png_debug
2541#define png_debug(l,m) _RPT0(_CRT_WARN,m PNG_STRING_NEWLINE)
2542#endif
2543#ifndef png_debug1
2544#define png_debug1(l,m,p1) _RPT1(_CRT_WARN,m PNG_STRING_NEWLINE,p1)
2545#endif
2546#ifndef png_debug2
2547#define png_debug2(l,m,p1,p2) _RPT2(_CRT_WARN,m PNG_STRING_NEWLINE,p1,p2)
2548#endif
2549#endif
2550#else /* PNG_DEBUG_FILE || !_MSC_VER */
2551#ifndef PNG_DEBUG_FILE
2552#define PNG_DEBUG_FILE stderr
2553#endif /* PNG_DEBUG_FILE */
2554#if (PNG_DEBUG > 1)
2555#ifndef png_debug
2556/* Note: ["%s"m PNG_STRING_NEWLINE] probably does not work on
2557 * non-ISO compilers */
2558#ifdef __STDC__
2559#define png_debug(l,m) \
2560{ \
2561 int num_tabs=l; \
2562 fprintf(PNG_DEBUG_FILE,"%s"m PNG_STRING_NEWLINE,(num_tabs==1 ? "\t" : \
2563 (num_tabs==2 ? "\t\t":(num_tabs>2 ? "\t\t\t":"")))); \
2564}
2565#endif
2566#ifndef png_debug1
2567#define png_debug1(l,m,p1) \
2568{ \
2569 int num_tabs=l; \
2570 fprintf(PNG_DEBUG_FILE,"%s"m PNG_STRING_NEWLINE,(num_tabs==1 ? "\t" : \
2571 (num_tabs==2 ? "\t\t":(num_tabs>2 ? "\t\t\t":""))),p1); \
2572}
2573#endif
2574#ifndef png_debug2
2575#define png_debug2(l,m,p1,p2) \
2576{ \
2577 int num_tabs=l; \
2578 fprintf(PNG_DEBUG_FILE,"%s"m PNG_STRING_NEWLINE,(num_tabs==1 ? "\t" : \
2579 (num_tabs==2 ? "\t\t":(num_tabs>2 ? "\t\t\t":""))),p1,p2); \
2580}
2581#endif
2582#else /* __STDC __ */
2583#ifndef png_debug
2584#define png_debug(l,m) \
2585 int num_tabs=l; \
2586 char format[256]; \
2587 snprintf(format,256,"%s%s%s",(num_tabs==1 ? "\t" : \
2588 (num_tabs==2 ? "\t\t":(num_tabs>2 ? "\t\t\t":""))), \
2589 m,PNG_STRING_NEWLINE); \
2590 fprintf(PNG_DEBUG_FILE,format);
2591#endif
2592#ifndef png_debug1
2593#define png_debug1(l,m,p1) \
2594 int num_tabs=l; \
2595 char format[256]; \
2596 snprintf(format,256,"%s%s%s",(num_tabs==1 ? "\t" : \
2597 (num_tabs==2 ? "\t\t":(num_tabs>2 ? "\t\t\t":""))), \
2598 m,PNG_STRING_NEWLINE); \
2599 fprintf(PNG_DEBUG_FILE,format,p1);
2600#endif
2601#ifndef png_debug2
2602#define png_debug2(l,m,p1,p2) \
2603 int num_tabs=l; \
2604 char format[256]; \
2605 snprintf(format,256,"%s%s%s",(num_tabs==1 ? "\t" : \
2606 (num_tabs==2 ? "\t\t":(num_tabs>2 ? "\t\t\t":""))), \
2607 m,PNG_STRING_NEWLINE); \
2608 fprintf(PNG_DEBUG_FILE,format,p1,p2);
2609#endif
2610#endif /* __STDC __ */
2611#endif /* (PNG_DEBUG > 1) */
2612#endif /* _MSC_VER */
2613#endif /* (PNG_DEBUG > 0) */
2614#endif /* PNG_DEBUG */
2615#ifndef png_debug
2616#define png_debug(l, m)
2617#endif
2618#ifndef png_debug1
2619#define png_debug1(l, m, p1)
2620#endif
2621#ifndef png_debug2
2622#define png_debug2(l, m, p1, p2)
2623#endif
2624
2625extern PNG_EXPORT(png_charp,png_get_copyright) PNGARG((png_structp png_ptr));
2626extern PNG_EXPORT(png_charp,png_get_header_ver) PNGARG((png_structp png_ptr));
2627extern PNG_EXPORT(png_charp,png_get_header_version) PNGARG((png_structp png_ptr));
2628extern PNG_EXPORT(png_charp,png_get_libpng_ver) PNGARG((png_structp png_ptr));
2629
2630#ifdef PNG_MNG_FEATURES_SUPPORTED
2631extern PNG_EXPORT(png_uint_32,png_permit_mng_features) PNGARG((png_structp
2632 png_ptr, png_uint_32 mng_features_permitted));
2633#endif
2634
2635/* For use in png_set_keep_unknown, added to version 1.2.6 */
2636#define PNG_HANDLE_CHUNK_AS_DEFAULT 0
2637#define PNG_HANDLE_CHUNK_NEVER 1
2638#define PNG_HANDLE_CHUNK_IF_SAFE 2
2639#define PNG_HANDLE_CHUNK_ALWAYS 3
2640
2641/* Added to version 1.2.0 */
2642#if defined(PNG_ASSEMBLER_CODE_SUPPORTED)
2643#if defined(PNG_MMX_CODE_SUPPORTED)
2644#define PNG_ASM_FLAG_MMX_SUPPORT_COMPILED 0x01 /* not user-settable */
2645#define PNG_ASM_FLAG_MMX_SUPPORT_IN_CPU 0x02 /* not user-settable */
2646#define PNG_ASM_FLAG_MMX_READ_COMBINE_ROW 0x04
2647#define PNG_ASM_FLAG_MMX_READ_INTERLACE 0x08
2648#define PNG_ASM_FLAG_MMX_READ_FILTER_SUB 0x10
2649#define PNG_ASM_FLAG_MMX_READ_FILTER_UP 0x20
2650#define PNG_ASM_FLAG_MMX_READ_FILTER_AVG 0x40
2651#define PNG_ASM_FLAG_MMX_READ_FILTER_PAETH 0x80
2652#define PNG_ASM_FLAGS_INITIALIZED 0x80000000 /* not user-settable */
2653
2654#define PNG_MMX_READ_FLAGS ( PNG_ASM_FLAG_MMX_READ_COMBINE_ROW \
2655 | PNG_ASM_FLAG_MMX_READ_INTERLACE \
2656 | PNG_ASM_FLAG_MMX_READ_FILTER_SUB \
2657 | PNG_ASM_FLAG_MMX_READ_FILTER_UP \
2658 | PNG_ASM_FLAG_MMX_READ_FILTER_AVG \
2659 | PNG_ASM_FLAG_MMX_READ_FILTER_PAETH )
2660#define PNG_MMX_WRITE_FLAGS ( 0 )
2661
2662#define PNG_MMX_FLAGS ( PNG_ASM_FLAG_MMX_SUPPORT_COMPILED \
2663 | PNG_ASM_FLAG_MMX_SUPPORT_IN_CPU \
2664 | PNG_MMX_READ_FLAGS \
2665 | PNG_MMX_WRITE_FLAGS )
2666
2667#define PNG_SELECT_READ 1
2668#define PNG_SELECT_WRITE 2
2669#endif /* PNG_MMX_CODE_SUPPORTED */
2670
2671#if !defined(PNG_1_0_X)
2672/* pngget.c */
2673extern PNG_EXPORT(png_uint_32,png_get_mmx_flagmask)
2674 PNGARG((int flag_select, int *compilerID));
2675
2676/* pngget.c */
2677extern PNG_EXPORT(png_uint_32,png_get_asm_flagmask)
2678 PNGARG((int flag_select));
2679
2680/* pngget.c */
2681extern PNG_EXPORT(png_uint_32,png_get_asm_flags)
2682 PNGARG((png_structp png_ptr));
2683
2684/* pngget.c */
2685extern PNG_EXPORT(png_byte,png_get_mmx_bitdepth_threshold)
2686 PNGARG((png_structp png_ptr));
2687
2688/* pngget.c */
2689extern PNG_EXPORT(png_uint_32,png_get_mmx_rowbytes_threshold)
2690 PNGARG((png_structp png_ptr));
2691
2692/* pngset.c */
2693extern PNG_EXPORT(void,png_set_asm_flags)
2694 PNGARG((png_structp png_ptr, png_uint_32 asm_flags));
2695
2696/* pngset.c */
2697extern PNG_EXPORT(void,png_set_mmx_thresholds)
2698 PNGARG((png_structp png_ptr, png_byte mmx_bitdepth_threshold,
2699 png_uint_32 mmx_rowbytes_threshold));
2700
2701#endif /* PNG_1_0_X */
2702
2703#if !defined(PNG_1_0_X)
2704/* png.c, pnggccrd.c, or pngvcrd.c */
2705extern PNG_EXPORT(int,png_mmx_support) PNGARG((void));
2706#endif /* PNG_ASSEMBLER_CODE_SUPPORTED */
2707
2708/* Strip the prepended error numbers ("#nnn ") from error and warning
2709 * messages before passing them to the error or warning handler. */
2710#ifdef PNG_ERROR_NUMBERS_SUPPORTED
2711extern PNG_EXPORT(void,png_set_strip_error_numbers) PNGARG((png_structp
2712 png_ptr, png_uint_32 strip_mode));
2713#endif
2714
2715#endif /* PNG_1_0_X */
2716
2717/* Added at libpng-1.2.6 */
2718#ifdef PNG_SET_USER_LIMITS_SUPPORTED
2719extern PNG_EXPORT(void,png_set_user_limits) PNGARG((png_structp
2720 png_ptr, png_uint_32 user_width_max, png_uint_32 user_height_max));
2721extern PNG_EXPORT(png_uint_32,png_get_user_width_max) PNGARG((png_structp
2722 png_ptr));
2723extern PNG_EXPORT(png_uint_32,png_get_user_height_max) PNGARG((png_structp
2724 png_ptr));
2725#endif
2726
2727
2728/* Maintainer: Put new public prototypes here ^, in libpng.3, and project defs */
2729
2730#ifdef PNG_READ_COMPOSITE_NODIV_SUPPORTED
2731/* With these routines we avoid an integer divide, which will be slower on
2732 * most machines. However, it does take more operations than the corresponding
2733 * divide method, so it may be slower on a few RISC systems. There are two
2734 * shifts (by 8 or 16 bits) and an addition, versus a single integer divide.
2735 *
2736 * Note that the rounding factors are NOT supposed to be the same! 128 and
2737 * 32768 are correct for the NODIV code; 127 and 32767 are correct for the
2738 * standard method.
2739 *
2740 * [Optimized code by Greg Roelofs and Mark Adler...blame us for bugs. :-) ]
2741 */
2742
2743 /* fg and bg should be in `gamma 1.0' space; alpha is the opacity */
2744
2745# define png_composite(composite, fg, alpha, bg) \
2746 { png_uint_16 temp = (png_uint_16)((png_uint_16)(fg) * (png_uint_16)(alpha) \
2747 + (png_uint_16)(bg)*(png_uint_16)(255 - \
2748 (png_uint_16)(alpha)) + (png_uint_16)128); \
2749 (composite) = (png_byte)((temp + (temp >> 8)) >> 8); }
2750
2751# define png_composite_16(composite, fg, alpha, bg) \
2752 { png_uint_32 temp = (png_uint_32)((png_uint_32)(fg) * (png_uint_32)(alpha) \
2753 + (png_uint_32)(bg)*(png_uint_32)(65535L - \
2754 (png_uint_32)(alpha)) + (png_uint_32)32768L); \
2755 (composite) = (png_uint_16)((temp + (temp >> 16)) >> 16); }
2756
2757#else /* standard method using integer division */
2758
2759# define png_composite(composite, fg, alpha, bg) \
2760 (composite) = (png_byte)(((png_uint_16)(fg) * (png_uint_16)(alpha) + \
2761 (png_uint_16)(bg) * (png_uint_16)(255 - (png_uint_16)(alpha)) + \
2762 (png_uint_16)127) / 255)
2763
2764# define png_composite_16(composite, fg, alpha, bg) \
2765 (composite) = (png_uint_16)(((png_uint_32)(fg) * (png_uint_32)(alpha) + \
2766 (png_uint_32)(bg)*(png_uint_32)(65535L - (png_uint_32)(alpha)) + \
2767 (png_uint_32)32767) / (png_uint_32)65535L)
2768
2769#endif /* PNG_READ_COMPOSITE_NODIV_SUPPORTED */
2770
2771/* Inline macros to do direct reads of bytes from the input buffer. These
2772 * require that you are using an architecture that uses PNG byte ordering
2773 * (MSB first) and supports unaligned data storage. I think that PowerPC
2774 * in big-endian mode and 680x0 are the only ones that will support this.
2775 * The x86 line of processors definitely do not. The png_get_int_32()
2776 * routine also assumes we are using two's complement format for negative
2777 * values, which is almost certainly true.
2778 */
2779#if defined(PNG_READ_BIG_ENDIAN_SUPPORTED)
2780# define png_get_uint_32(buf) ( *((png_uint_32p) (buf)))
2781# define png_get_uint_16(buf) ( *((png_uint_16p) (buf)))
2782# define png_get_int_32(buf) ( *((png_int_32p) (buf)))
2783#else
2784extern PNG_EXPORT(png_uint_32,png_get_uint_32) PNGARG((png_bytep buf));
2785extern PNG_EXPORT(png_uint_16,png_get_uint_16) PNGARG((png_bytep buf));
2786extern PNG_EXPORT(png_int_32,png_get_int_32) PNGARG((png_bytep buf));
2787#endif /* !PNG_READ_BIG_ENDIAN_SUPPORTED */
2788extern PNG_EXPORT(png_uint_32,png_get_uint_31)
2789 PNGARG((png_structp png_ptr, png_bytep buf));
2790/* No png_get_int_16 -- may be added if there's a real need for it. */
2791
2792/* Place a 32-bit number into a buffer in PNG byte order (big-endian).
2793 */
2794extern PNG_EXPORT(void,png_save_uint_32)
2795 PNGARG((png_bytep buf, png_uint_32 i));
2796extern PNG_EXPORT(void,png_save_int_32)
2797 PNGARG((png_bytep buf, png_int_32 i));
2798
2799/* Place a 16-bit number into a buffer in PNG byte order.
2800 * The parameter is declared unsigned int, not png_uint_16,
2801 * just to avoid potential problems on pre-ANSI C compilers.
2802 */
2803extern PNG_EXPORT(void,png_save_uint_16)
2804 PNGARG((png_bytep buf, unsigned int i));
2805/* No png_save_int_16 -- may be added if there's a real need for it. */
2806
2807/* ************************************************************************* */
2808
2809/* These next functions are used internally in the code. They generally
2810 * shouldn't be used unless you are writing code to add or replace some
2811 * functionality in libpng. More information about most functions can
2812 * be found in the files where the functions are located.
2813 */
2814
2815
2816/* Various modes of operation, that are visible to applications because
2817 * they are used for unknown chunk location.
2818 */
2819#define PNG_HAVE_IHDR 0x01
2820#define PNG_HAVE_PLTE 0x02
2821#define PNG_HAVE_IDAT 0x04
2822#define PNG_AFTER_IDAT 0x08 /* Have complete zlib datastream */
2823#define PNG_HAVE_IEND 0x10
2824
2825#if defined(PNG_INTERNAL)
2826
2827/* More modes of operation. Note that after an init, mode is set to
2828 * zero automatically when the structure is created.
2829 */
2830#define PNG_HAVE_gAMA 0x20
2831#define PNG_HAVE_cHRM 0x40
2832#define PNG_HAVE_sRGB 0x80
2833#define PNG_HAVE_CHUNK_HEADER 0x100
2834#define PNG_WROTE_tIME 0x200
2835#define PNG_WROTE_INFO_BEFORE_PLTE 0x400
2836#define PNG_BACKGROUND_IS_GRAY 0x800
2837#define PNG_HAVE_PNG_SIGNATURE 0x1000
2838#define PNG_HAVE_CHUNK_AFTER_IDAT 0x2000 /* Have another chunk after IDAT */
2839
2840/* flags for the transformations the PNG library does on the image data */
2841#define PNG_BGR 0x0001
2842#define PNG_INTERLACE 0x0002
2843#define PNG_PACK 0x0004
2844#define PNG_SHIFT 0x0008
2845#define PNG_SWAP_BYTES 0x0010
2846#define PNG_INVERT_MONO 0x0020
2847#define PNG_DITHER 0x0040
2848#define PNG_BACKGROUND 0x0080
2849#define PNG_BACKGROUND_EXPAND 0x0100
2850 /* 0x0200 unused */
2851#define PNG_16_TO_8 0x0400
2852#define PNG_RGBA 0x0800
2853#define PNG_EXPAND 0x1000
2854#define PNG_GAMMA 0x2000
2855#define PNG_GRAY_TO_RGB 0x4000
2856#define PNG_FILLER 0x8000L
2857#define PNG_PACKSWAP 0x10000L
2858#define PNG_SWAP_ALPHA 0x20000L
2859#define PNG_STRIP_ALPHA 0x40000L
2860#define PNG_INVERT_ALPHA 0x80000L
2861#define PNG_USER_TRANSFORM 0x100000L
2862#define PNG_RGB_TO_GRAY_ERR 0x200000L
2863#define PNG_RGB_TO_GRAY_WARN 0x400000L
2864#define PNG_RGB_TO_GRAY 0x600000L /* two bits, RGB_TO_GRAY_ERR|WARN */
2865 /* 0x800000L Unused */
2866#define PNG_ADD_ALPHA 0x1000000L /* Added to libpng-1.2.7 */
2867#define PNG_EXPAND_tRNS 0x2000000L /* Added to libpng-1.2.9 */
2868 /* 0x4000000L unused */
2869 /* 0x8000000L unused */
2870 /* 0x10000000L unused */
2871 /* 0x20000000L unused */
2872 /* 0x40000000L unused */
2873
2874/* flags for png_create_struct */
2875#define PNG_STRUCT_PNG 0x0001
2876#define PNG_STRUCT_INFO 0x0002
2877
2878/* Scaling factor for filter heuristic weighting calculations */
2879#define PNG_WEIGHT_SHIFT 8
2880#define PNG_WEIGHT_FACTOR (1<<(PNG_WEIGHT_SHIFT))
2881#define PNG_COST_SHIFT 3
2882#define PNG_COST_FACTOR (1<<(PNG_COST_SHIFT))
2883
2884/* flags for the png_ptr->flags rather than declaring a byte for each one */
2885#define PNG_FLAG_ZLIB_CUSTOM_STRATEGY 0x0001
2886#define PNG_FLAG_ZLIB_CUSTOM_LEVEL 0x0002
2887#define PNG_FLAG_ZLIB_CUSTOM_MEM_LEVEL 0x0004
2888#define PNG_FLAG_ZLIB_CUSTOM_WINDOW_BITS 0x0008
2889#define PNG_FLAG_ZLIB_CUSTOM_METHOD 0x0010
2890#define PNG_FLAG_ZLIB_FINISHED 0x0020
2891#define PNG_FLAG_ROW_INIT 0x0040
2892#define PNG_FLAG_FILLER_AFTER 0x0080
2893#define PNG_FLAG_CRC_ANCILLARY_USE 0x0100
2894#define PNG_FLAG_CRC_ANCILLARY_NOWARN 0x0200
2895#define PNG_FLAG_CRC_CRITICAL_USE 0x0400
2896#define PNG_FLAG_CRC_CRITICAL_IGNORE 0x0800
2897#define PNG_FLAG_FREE_PLTE 0x1000
2898#define PNG_FLAG_FREE_TRNS 0x2000
2899#define PNG_FLAG_FREE_HIST 0x4000
2900#define PNG_FLAG_KEEP_UNKNOWN_CHUNKS 0x8000L
2901#define PNG_FLAG_KEEP_UNSAFE_CHUNKS 0x10000L
2902#define PNG_FLAG_LIBRARY_MISMATCH 0x20000L
2903#define PNG_FLAG_STRIP_ERROR_NUMBERS 0x40000L
2904#define PNG_FLAG_STRIP_ERROR_TEXT 0x80000L
2905#define PNG_FLAG_MALLOC_NULL_MEM_OK 0x100000L
2906#define PNG_FLAG_ADD_ALPHA 0x200000L /* Added to libpng-1.2.8 */
2907#define PNG_FLAG_STRIP_ALPHA 0x400000L /* Added to libpng-1.2.8 */
2908 /* 0x800000L unused */
2909 /* 0x1000000L unused */
2910 /* 0x2000000L unused */
2911 /* 0x4000000L unused */
2912 /* 0x8000000L unused */
2913 /* 0x10000000L unused */
2914 /* 0x20000000L unused */
2915 /* 0x40000000L unused */
2916
2917#define PNG_FLAG_CRC_ANCILLARY_MASK (PNG_FLAG_CRC_ANCILLARY_USE | \
2918 PNG_FLAG_CRC_ANCILLARY_NOWARN)
2919
2920#define PNG_FLAG_CRC_CRITICAL_MASK (PNG_FLAG_CRC_CRITICAL_USE | \
2921 PNG_FLAG_CRC_CRITICAL_IGNORE)
2922
2923#define PNG_FLAG_CRC_MASK (PNG_FLAG_CRC_ANCILLARY_MASK | \
2924 PNG_FLAG_CRC_CRITICAL_MASK)
2925
2926/* save typing and make code easier to understand */
2927
2928#define PNG_COLOR_DIST(c1, c2) (abs((int)((c1).red) - (int)((c2).red)) + \
2929 abs((int)((c1).green) - (int)((c2).green)) + \
2930 abs((int)((c1).blue) - (int)((c2).blue)))
2931
2932/* Added to libpng-1.2.6 JB */
2933#define PNG_ROWBYTES(pixel_bits, width) \
2934 ((pixel_bits) >= 8 ? \
2935 ((width) * (((png_uint_32)(pixel_bits)) >> 3)) : \
2936 (( ((width) * ((png_uint_32)(pixel_bits))) + 7) >> 3) )
2937
2938/* PNG_OUT_OF_RANGE returns true if value is outside the range
2939 ideal-delta..ideal+delta. Each argument is evaluated twice.
2940 "ideal" and "delta" should be constants, normally simple
2941 integers, "value" a variable. Added to libpng-1.2.6 JB */
2942#define PNG_OUT_OF_RANGE(value, ideal, delta) \
2943 ( (value) < (ideal)-(delta) || (value) > (ideal)+(delta) )
2944
2945/* variables declared in png.c - only it needs to define PNG_NO_EXTERN */
2946#if !defined(PNG_NO_EXTERN) || defined(PNG_ALWAYS_EXTERN)
2947/* place to hold the signature string for a PNG file. */
2948#ifdef PNG_USE_GLOBAL_ARRAYS
2949 PNG_EXPORT_VAR (PNG_CONST png_byte FARDATA) png_sig[8];
2950#else
2951#endif
2952#endif /* PNG_NO_EXTERN */
2953
2954/* Constant strings for known chunk types. If you need to add a chunk,
2955 * define the name here, and add an invocation of the macro in png.c and
2956 * wherever it's needed.
2957 */
2958#define PNG_IHDR png_byte png_IHDR[5] = { 73, 72, 68, 82, '\0'}
2959#define PNG_IDAT png_byte png_IDAT[5] = { 73, 68, 65, 84, '\0'}
2960#define PNG_IEND png_byte png_IEND[5] = { 73, 69, 78, 68, '\0'}
2961#define PNG_PLTE png_byte png_PLTE[5] = { 80, 76, 84, 69, '\0'}
2962#define PNG_bKGD png_byte png_bKGD[5] = { 98, 75, 71, 68, '\0'}
2963#define PNG_cHRM png_byte png_cHRM[5] = { 99, 72, 82, 77, '\0'}
2964#define PNG_gAMA png_byte png_gAMA[5] = {103, 65, 77, 65, '\0'}
2965#define PNG_hIST png_byte png_hIST[5] = {104, 73, 83, 84, '\0'}
2966#define PNG_iCCP png_byte png_iCCP[5] = {105, 67, 67, 80, '\0'}
2967#define PNG_iTXt png_byte png_iTXt[5] = {105, 84, 88, 116, '\0'}
2968#define PNG_oFFs png_byte png_oFFs[5] = {111, 70, 70, 115, '\0'}
2969#define PNG_pCAL png_byte png_pCAL[5] = {112, 67, 65, 76, '\0'}
2970#define PNG_sCAL png_byte png_sCAL[5] = {115, 67, 65, 76, '\0'}
2971#define PNG_pHYs png_byte png_pHYs[5] = {112, 72, 89, 115, '\0'}
2972#define PNG_sBIT png_byte png_sBIT[5] = {115, 66, 73, 84, '\0'}
2973#define PNG_sPLT png_byte png_sPLT[5] = {115, 80, 76, 84, '\0'}
2974#define PNG_sRGB png_byte png_sRGB[5] = {115, 82, 71, 66, '\0'}
2975#define PNG_tEXt png_byte png_tEXt[5] = {116, 69, 88, 116, '\0'}
2976#define PNG_tIME png_byte png_tIME[5] = {116, 73, 77, 69, '\0'}
2977#define PNG_tRNS png_byte png_tRNS[5] = {116, 82, 78, 83, '\0'}
2978#define PNG_zTXt png_byte png_zTXt[5] = {122, 84, 88, 116, '\0'}
2979
2980#ifdef PNG_USE_GLOBAL_ARRAYS
2981PNG_EXPORT_VAR (png_byte FARDATA) png_IHDR[5];
2982PNG_EXPORT_VAR (png_byte FARDATA) png_IDAT[5];
2983PNG_EXPORT_VAR (png_byte FARDATA) png_IEND[5];
2984PNG_EXPORT_VAR (png_byte FARDATA) png_PLTE[5];
2985PNG_EXPORT_VAR (png_byte FARDATA) png_bKGD[5];
2986PNG_EXPORT_VAR (png_byte FARDATA) png_cHRM[5];
2987PNG_EXPORT_VAR (png_byte FARDATA) png_gAMA[5];
2988PNG_EXPORT_VAR (png_byte FARDATA) png_hIST[5];
2989PNG_EXPORT_VAR (png_byte FARDATA) png_iCCP[5];
2990PNG_EXPORT_VAR (png_byte FARDATA) png_iTXt[5];
2991PNG_EXPORT_VAR (png_byte FARDATA) png_oFFs[5];
2992PNG_EXPORT_VAR (png_byte FARDATA) png_pCAL[5];
2993PNG_EXPORT_VAR (png_byte FARDATA) png_sCAL[5];
2994PNG_EXPORT_VAR (png_byte FARDATA) png_pHYs[5];
2995PNG_EXPORT_VAR (png_byte FARDATA) png_sBIT[5];
2996PNG_EXPORT_VAR (png_byte FARDATA) png_sPLT[5];
2997PNG_EXPORT_VAR (png_byte FARDATA) png_sRGB[5];
2998PNG_EXPORT_VAR (png_byte FARDATA) png_tEXt[5];
2999PNG_EXPORT_VAR (png_byte FARDATA) png_tIME[5];
3000PNG_EXPORT_VAR (png_byte FARDATA) png_tRNS[5];
3001PNG_EXPORT_VAR (png_byte FARDATA) png_zTXt[5];
3002#endif /* PNG_USE_GLOBAL_ARRAYS */
3003
3004#if defined(PNG_1_0_X) || defined (PNG_1_2_X)
3005/* Initialize png_ptr struct for reading, and allocate any other memory.
3006 * (old interface - DEPRECATED - use png_create_read_struct instead).
3007 */
3008extern PNG_EXPORT(void,png_read_init) PNGARG((png_structp png_ptr));
3009#undef png_read_init
3010#define png_read_init(png_ptr) png_read_init_3(&png_ptr, \
3011 PNG_LIBPNG_VER_STRING, png_sizeof(png_struct));
3012#endif
3013
3014extern PNG_EXPORT(void,png_read_init_3) PNGARG((png_structpp ptr_ptr,
3015 png_const_charp user_png_ver, png_size_t png_struct_size));
3016#if defined(PNG_1_0_X) || defined (PNG_1_2_X)
3017extern PNG_EXPORT(void,png_read_init_2) PNGARG((png_structp png_ptr,
3018 png_const_charp user_png_ver, png_size_t png_struct_size, png_size_t
3019 png_info_size));
3020#endif
3021
3022#if defined(PNG_1_0_X) || defined (PNG_1_2_X)
3023/* Initialize png_ptr struct for writing, and allocate any other memory.
3024 * (old interface - DEPRECATED - use png_create_write_struct instead).
3025 */
3026extern PNG_EXPORT(void,png_write_init) PNGARG((png_structp png_ptr));
3027#undef png_write_init
3028#define png_write_init(png_ptr) png_write_init_3(&png_ptr, \
3029 PNG_LIBPNG_VER_STRING, png_sizeof(png_struct));
3030#endif
3031
3032extern PNG_EXPORT(void,png_write_init_3) PNGARG((png_structpp ptr_ptr,
3033 png_const_charp user_png_ver, png_size_t png_struct_size));
3034extern PNG_EXPORT(void,png_write_init_2) PNGARG((png_structp png_ptr,
3035 png_const_charp user_png_ver, png_size_t png_struct_size, png_size_t
3036 png_info_size));
3037
3038/* Allocate memory for an internal libpng struct */
3039PNG_EXTERN png_voidp png_create_struct PNGARG((int type));
3040
3041/* Free memory from internal libpng struct */
3042PNG_EXTERN void png_destroy_struct PNGARG((png_voidp struct_ptr));
3043
3044PNG_EXTERN png_voidp png_create_struct_2 PNGARG((int type, png_malloc_ptr
3045 malloc_fn, png_voidp mem_ptr));
3046PNG_EXTERN void png_destroy_struct_2 PNGARG((png_voidp struct_ptr,
3047 png_free_ptr free_fn, png_voidp mem_ptr));
3048
3049/* Free any memory that info_ptr points to and reset struct. */
3050PNG_EXTERN void png_info_destroy PNGARG((png_structp png_ptr,
3051 png_infop info_ptr));
3052
3053#ifndef PNG_1_0_X
3054/* Function to allocate memory for zlib. */
3055PNG_EXTERN voidpf png_zalloc PNGARG((voidpf png_ptr, uInt items, uInt size));
3056
3057/* Function to free memory for zlib */
3058PNG_EXTERN void png_zfree PNGARG((voidpf png_ptr, voidpf ptr));
3059
3060#ifdef PNG_SIZE_T
3061/* Function to convert a sizeof an item to png_sizeof item */
3062 PNG_EXTERN png_size_t PNGAPI png_convert_size PNGARG((size_t size));
3063#endif
3064
3065/* Next four functions are used internally as callbacks. PNGAPI is required
3066 * but not PNG_EXPORT. PNGAPI added at libpng version 1.2.3. */
3067
3068PNG_EXTERN void PNGAPI png_default_read_data PNGARG((png_structp png_ptr,
3069 png_bytep data, png_size_t length));
3070
3071#ifdef PNG_PROGRESSIVE_READ_SUPPORTED
3072PNG_EXTERN void PNGAPI png_push_fill_buffer PNGARG((png_structp png_ptr,
3073 png_bytep buffer, png_size_t length));
3074#endif
3075
3076PNG_EXTERN void PNGAPI png_default_write_data PNGARG((png_structp png_ptr,
3077 png_bytep data, png_size_t length));
3078
3079#if defined(PNG_WRITE_FLUSH_SUPPORTED)
3080#if !defined(PNG_NO_STDIO)
3081PNG_EXTERN void PNGAPI png_default_flush PNGARG((png_structp png_ptr));
3082#endif
3083#endif
3084#else /* PNG_1_0_X */
3085#ifdef PNG_PROGRESSIVE_READ_SUPPORTED
3086PNG_EXTERN void png_push_fill_buffer PNGARG((png_structp png_ptr,
3087 png_bytep buffer, png_size_t length));
3088#endif
3089#endif /* PNG_1_0_X */
3090
3091/* Reset the CRC variable */
3092PNG_EXTERN void png_reset_crc PNGARG((png_structp png_ptr));
3093
3094/* Write the "data" buffer to whatever output you are using. */
3095PNG_EXTERN void png_write_data PNGARG((png_structp png_ptr, png_bytep data,
3096 png_size_t length));
3097
3098/* Read data from whatever input you are using into the "data" buffer */
3099PNG_EXTERN void png_read_data PNGARG((png_structp png_ptr, png_bytep data,
3100 png_size_t length));
3101
3102/* Read bytes into buf, and update png_ptr->crc */
3103PNG_EXTERN void png_crc_read PNGARG((png_structp png_ptr, png_bytep buf,
3104 png_size_t length));
3105
3106/* Decompress data in a chunk that uses compression */
3107#if defined(PNG_zTXt_SUPPORTED) || defined(PNG_iTXt_SUPPORTED) || \
3108 defined(PNG_iCCP_SUPPORTED) || defined(PNG_sPLT_SUPPORTED)
3109PNG_EXTERN void png_decompress_chunk PNGARG((png_structp png_ptr,
3110 int comp_type, png_size_t chunklength,
3111 png_size_t prefix_length, png_size_t *data_length));
3112#endif
3113
3114/* Read "skip" bytes, read the file crc, and (optionally) verify png_ptr->crc */
3115PNG_EXTERN int png_crc_finish PNGARG((png_structp png_ptr, png_uint_32 skip));
3116
3117/* Read the CRC from the file and compare it to the libpng calculated CRC */
3118PNG_EXTERN int png_crc_error PNGARG((png_structp png_ptr));
3119
3120/* Calculate the CRC over a section of data. Note that we are only
3121 * passing a maximum of 64K on systems that have this as a memory limit,
3122 * since this is the maximum buffer size we can specify.
3123 */
3124PNG_EXTERN void png_calculate_crc PNGARG((png_structp png_ptr, png_bytep ptr,
3125 png_size_t length));
3126
3127#if defined(PNG_WRITE_FLUSH_SUPPORTED)
3128PNG_EXTERN void png_flush PNGARG((png_structp png_ptr));
3129#endif
3130
3131/* simple function to write the signature */
3132PNG_EXTERN void png_write_sig PNGARG((png_structp png_ptr));
3133
3134/* write various chunks */
3135
3136/* Write the IHDR chunk, and update the png_struct with the necessary
3137 * information.
3138 */
3139PNG_EXTERN void png_write_IHDR PNGARG((png_structp png_ptr, png_uint_32 width,
3140 png_uint_32 height,
3141 int bit_depth, int color_type, int compression_method, int filter_method,
3142 int interlace_method));
3143
3144PNG_EXTERN void png_write_PLTE PNGARG((png_structp png_ptr, png_colorp palette,
3145 png_uint_32 num_pal));
3146
3147PNG_EXTERN void png_write_IDAT PNGARG((png_structp png_ptr, png_bytep data,
3148 png_size_t length));
3149
3150PNG_EXTERN void png_write_IEND PNGARG((png_structp png_ptr));
3151
3152#if defined(PNG_WRITE_gAMA_SUPPORTED)
3153#ifdef PNG_FLOATING_POINT_SUPPORTED
3154PNG_EXTERN void png_write_gAMA PNGARG((png_structp png_ptr, double file_gamma));
3155#endif
3156#ifdef PNG_FIXED_POINT_SUPPORTED
3157PNG_EXTERN void png_write_gAMA_fixed PNGARG((png_structp png_ptr, png_fixed_point
3158 file_gamma));
3159#endif
3160#endif
3161
3162#if defined(PNG_WRITE_sBIT_SUPPORTED)
3163PNG_EXTERN void png_write_sBIT PNGARG((png_structp png_ptr, png_color_8p sbit,
3164 int color_type));
3165#endif
3166
3167#if defined(PNG_WRITE_cHRM_SUPPORTED)
3168#ifdef PNG_FLOATING_POINT_SUPPORTED
3169PNG_EXTERN void png_write_cHRM PNGARG((png_structp png_ptr,
3170 double white_x, double white_y,
3171 double red_x, double red_y, double green_x, double green_y,
3172 double blue_x, double blue_y));
3173#endif
3174#ifdef PNG_FIXED_POINT_SUPPORTED
3175PNG_EXTERN void png_write_cHRM_fixed PNGARG((png_structp png_ptr,
3176 png_fixed_point int_white_x, png_fixed_point int_white_y,
3177 png_fixed_point int_red_x, png_fixed_point int_red_y, png_fixed_point
3178 int_green_x, png_fixed_point int_green_y, png_fixed_point int_blue_x,
3179 png_fixed_point int_blue_y));
3180#endif
3181#endif
3182
3183#if defined(PNG_WRITE_sRGB_SUPPORTED)
3184PNG_EXTERN void png_write_sRGB PNGARG((png_structp png_ptr,
3185 int intent));
3186#endif
3187
3188#if defined(PNG_WRITE_iCCP_SUPPORTED)
3189PNG_EXTERN void png_write_iCCP PNGARG((png_structp png_ptr,
3190 png_charp name, int compression_type,
3191 png_charp profile, int proflen));
3192 /* Note to maintainer: profile should be png_bytep */
3193#endif
3194
3195#if defined(PNG_WRITE_sPLT_SUPPORTED)
3196PNG_EXTERN void png_write_sPLT PNGARG((png_structp png_ptr,
3197 png_sPLT_tp palette));
3198#endif
3199
3200#if defined(PNG_WRITE_tRNS_SUPPORTED)
3201PNG_EXTERN void png_write_tRNS PNGARG((png_structp png_ptr, png_bytep trans,
3202 png_color_16p values, int number, int color_type));
3203#endif
3204
3205#if defined(PNG_WRITE_bKGD_SUPPORTED)
3206PNG_EXTERN void png_write_bKGD PNGARG((png_structp png_ptr,
3207 png_color_16p values, int color_type));
3208#endif
3209
3210#if defined(PNG_WRITE_hIST_SUPPORTED)
3211PNG_EXTERN void png_write_hIST PNGARG((png_structp png_ptr, png_uint_16p hist,
3212 int num_hist));
3213#endif
3214
3215#if defined(PNG_WRITE_TEXT_SUPPORTED) || defined(PNG_WRITE_pCAL_SUPPORTED) || \
3216 defined(PNG_WRITE_iCCP_SUPPORTED) || defined(PNG_WRITE_sPLT_SUPPORTED)
3217PNG_EXTERN png_size_t png_check_keyword PNGARG((png_structp png_ptr,
3218 png_charp key, png_charpp new_key));
3219#endif
3220
3221#if defined(PNG_WRITE_tEXt_SUPPORTED)
3222PNG_EXTERN void png_write_tEXt PNGARG((png_structp png_ptr, png_charp key,
3223 png_charp text, png_size_t text_len));
3224#endif
3225
3226#if defined(PNG_WRITE_zTXt_SUPPORTED)
3227PNG_EXTERN void png_write_zTXt PNGARG((png_structp png_ptr, png_charp key,
3228 png_charp text, png_size_t text_len, int compression));
3229#endif
3230
3231#if defined(PNG_WRITE_iTXt_SUPPORTED)
3232PNG_EXTERN void png_write_iTXt PNGARG((png_structp png_ptr,
3233 int compression, png_charp key, png_charp lang, png_charp lang_key,
3234 png_charp text));
3235#endif
3236
3237#if defined(PNG_TEXT_SUPPORTED) /* Added at version 1.0.14 and 1.2.4 */
3238PNG_EXTERN int png_set_text_2 PNGARG((png_structp png_ptr,
3239 png_infop info_ptr, png_textp text_ptr, int num_text));
3240#endif
3241
3242#if defined(PNG_WRITE_oFFs_SUPPORTED)
3243PNG_EXTERN void png_write_oFFs PNGARG((png_structp png_ptr,
3244 png_int_32 x_offset, png_int_32 y_offset, int unit_type));
3245#endif
3246
3247#if defined(PNG_WRITE_pCAL_SUPPORTED)
3248PNG_EXTERN void png_write_pCAL PNGARG((png_structp png_ptr, png_charp purpose,
3249 png_int_32 X0, png_int_32 X1, int type, int nparams,
3250 png_charp units, png_charpp params));
3251#endif
3252
3253#if defined(PNG_WRITE_pHYs_SUPPORTED)
3254PNG_EXTERN void png_write_pHYs PNGARG((png_structp png_ptr,
3255 png_uint_32 x_pixels_per_unit, png_uint_32 y_pixels_per_unit,
3256 int unit_type));
3257#endif
3258
3259#if defined(PNG_WRITE_tIME_SUPPORTED)
3260PNG_EXTERN void png_write_tIME PNGARG((png_structp png_ptr,
3261 png_timep mod_time));
3262#endif
3263
3264#if defined(PNG_WRITE_sCAL_SUPPORTED)
3265#if defined(PNG_FLOATING_POINT_SUPPORTED) && !defined(PNG_NO_STDIO)
3266PNG_EXTERN void png_write_sCAL PNGARG((png_structp png_ptr,
3267 int unit, double width, double height));
3268#else
3269#ifdef PNG_FIXED_POINT_SUPPORTED
3270PNG_EXTERN void png_write_sCAL_s PNGARG((png_structp png_ptr,
3271 int unit, png_charp width, png_charp height));
3272#endif
3273#endif
3274#endif
3275
3276/* Called when finished processing a row of data */
3277PNG_EXTERN void png_write_finish_row PNGARG((png_structp png_ptr));
3278
3279/* Internal use only. Called before first row of data */
3280PNG_EXTERN void png_write_start_row PNGARG((png_structp png_ptr));
3281
3282#if defined(PNG_READ_GAMMA_SUPPORTED)
3283PNG_EXTERN void png_build_gamma_table PNGARG((png_structp png_ptr));
3284#endif
3285
3286/* combine a row of data, dealing with alpha, etc. if requested */
3287PNG_EXTERN void png_combine_row PNGARG((png_structp png_ptr, png_bytep row,
3288 int mask));
3289
3290#if defined(PNG_READ_INTERLACING_SUPPORTED)
3291/* expand an interlaced row */
3292/* OLD pre-1.0.9 interface:
3293PNG_EXTERN void png_do_read_interlace PNGARG((png_row_infop row_info,
3294 png_bytep row, int pass, png_uint_32 transformations));
3295 */
3296PNG_EXTERN void png_do_read_interlace PNGARG((png_structp png_ptr));
3297#endif
3298
3299/* GRR TO DO (2.0 or whenever): simplify other internal calling interfaces */
3300
3301#if defined(PNG_WRITE_INTERLACING_SUPPORTED)
3302/* grab pixels out of a row for an interlaced pass */
3303PNG_EXTERN void png_do_write_interlace PNGARG((png_row_infop row_info,
3304 png_bytep row, int pass));
3305#endif
3306
3307/* unfilter a row */
3308PNG_EXTERN void png_read_filter_row PNGARG((png_structp png_ptr,
3309 png_row_infop row_info, png_bytep row, png_bytep prev_row, int filter));
3310
3311/* Choose the best filter to use and filter the row data */
3312PNG_EXTERN void png_write_find_filter PNGARG((png_structp png_ptr,
3313 png_row_infop row_info));
3314
3315/* Write out the filtered row. */
3316PNG_EXTERN void png_write_filtered_row PNGARG((png_structp png_ptr,
3317 png_bytep filtered_row));
3318/* finish a row while reading, dealing with interlacing passes, etc. */
3319PNG_EXTERN void png_read_finish_row PNGARG((png_structp png_ptr));
3320
3321/* initialize the row buffers, etc. */
3322PNG_EXTERN void png_read_start_row PNGARG((png_structp png_ptr));
3323/* optional call to update the users info structure */
3324PNG_EXTERN void png_read_transform_info PNGARG((png_structp png_ptr,
3325 png_infop info_ptr));
3326
3327/* these are the functions that do the transformations */
3328#if defined(PNG_READ_FILLER_SUPPORTED)
3329PNG_EXTERN void png_do_read_filler PNGARG((png_row_infop row_info,
3330 png_bytep row, png_uint_32 filler, png_uint_32 flags));
3331#endif
3332
3333#if defined(PNG_READ_SWAP_ALPHA_SUPPORTED)
3334PNG_EXTERN void png_do_read_swap_alpha PNGARG((png_row_infop row_info,
3335 png_bytep row));
3336#endif
3337
3338#if defined(PNG_WRITE_SWAP_ALPHA_SUPPORTED)
3339PNG_EXTERN void png_do_write_swap_alpha PNGARG((png_row_infop row_info,
3340 png_bytep row));
3341#endif
3342
3343#if defined(PNG_READ_INVERT_ALPHA_SUPPORTED)
3344PNG_EXTERN void png_do_read_invert_alpha PNGARG((png_row_infop row_info,
3345 png_bytep row));
3346#endif
3347
3348#if defined(PNG_WRITE_INVERT_ALPHA_SUPPORTED)
3349PNG_EXTERN void png_do_write_invert_alpha PNGARG((png_row_infop row_info,
3350 png_bytep row));
3351#endif
3352
3353#if defined(PNG_WRITE_FILLER_SUPPORTED) || \
3354 defined(PNG_READ_STRIP_ALPHA_SUPPORTED)
3355PNG_EXTERN void png_do_strip_filler PNGARG((png_row_infop row_info,
3356 png_bytep row, png_uint_32 flags));
3357#endif
3358
3359#if defined(PNG_READ_SWAP_SUPPORTED) || defined(PNG_WRITE_SWAP_SUPPORTED)
3360PNG_EXTERN void png_do_swap PNGARG((png_row_infop row_info, png_bytep row));
3361#endif
3362
3363#if defined(PNG_READ_PACKSWAP_SUPPORTED) || defined(PNG_WRITE_PACKSWAP_SUPPORTED)
3364PNG_EXTERN void png_do_packswap PNGARG((png_row_infop row_info, png_bytep row));
3365#endif
3366
3367#if defined(PNG_READ_RGB_TO_GRAY_SUPPORTED)
3368PNG_EXTERN int png_do_rgb_to_gray PNGARG((png_structp png_ptr, png_row_infop
3369 row_info, png_bytep row));
3370#endif
3371
3372#if defined(PNG_READ_GRAY_TO_RGB_SUPPORTED)
3373PNG_EXTERN void png_do_gray_to_rgb PNGARG((png_row_infop row_info,
3374 png_bytep row));
3375#endif
3376
3377#if defined(PNG_READ_PACK_SUPPORTED)
3378PNG_EXTERN void png_do_unpack PNGARG((png_row_infop row_info, png_bytep row));
3379#endif
3380
3381#if defined(PNG_READ_SHIFT_SUPPORTED)
3382PNG_EXTERN void png_do_unshift PNGARG((png_row_infop row_info, png_bytep row,
3383 png_color_8p sig_bits));
3384#endif
3385
3386#if defined(PNG_READ_INVERT_SUPPORTED) || defined(PNG_WRITE_INVERT_SUPPORTED)
3387PNG_EXTERN void png_do_invert PNGARG((png_row_infop row_info, png_bytep row));
3388#endif
3389
3390#if defined(PNG_READ_16_TO_8_SUPPORTED)
3391PNG_EXTERN void png_do_chop PNGARG((png_row_infop row_info, png_bytep row));
3392#endif
3393
3394#if defined(PNG_READ_DITHER_SUPPORTED)
3395PNG_EXTERN void png_do_dither PNGARG((png_row_infop row_info,
3396 png_bytep row, png_bytep palette_lookup, png_bytep dither_lookup));
3397
3398# if defined(PNG_CORRECT_PALETTE_SUPPORTED)
3399PNG_EXTERN void png_correct_palette PNGARG((png_structp png_ptr,
3400 png_colorp palette, int num_palette));
3401# endif
3402#endif
3403
3404#if defined(PNG_READ_BGR_SUPPORTED) || defined(PNG_WRITE_BGR_SUPPORTED)
3405PNG_EXTERN void png_do_bgr PNGARG((png_row_infop row_info, png_bytep row));
3406#endif
3407
3408#if defined(PNG_WRITE_PACK_SUPPORTED)
3409PNG_EXTERN void png_do_pack PNGARG((png_row_infop row_info,
3410 png_bytep row, png_uint_32 bit_depth));
3411#endif
3412
3413#if defined(PNG_WRITE_SHIFT_SUPPORTED)
3414PNG_EXTERN void png_do_shift PNGARG((png_row_infop row_info, png_bytep row,
3415 png_color_8p bit_depth));
3416#endif
3417
3418#if defined(PNG_READ_BACKGROUND_SUPPORTED)
3419#if defined(PNG_READ_GAMMA_SUPPORTED)
3420PNG_EXTERN void png_do_background PNGARG((png_row_infop row_info, png_bytep row,
3421 png_color_16p trans_values, png_color_16p background,
3422 png_color_16p background_1,
3423 png_bytep gamma_table, png_bytep gamma_from_1, png_bytep gamma_to_1,
3424 png_uint_16pp gamma_16, png_uint_16pp gamma_16_from_1,
3425 png_uint_16pp gamma_16_to_1, int gamma_shift));
3426#else
3427PNG_EXTERN void png_do_background PNGARG((png_row_infop row_info, png_bytep row,
3428 png_color_16p trans_values, png_color_16p background));
3429#endif
3430#endif
3431
3432#if defined(PNG_READ_GAMMA_SUPPORTED)
3433PNG_EXTERN void png_do_gamma PNGARG((png_row_infop row_info, png_bytep row,
3434 png_bytep gamma_table, png_uint_16pp gamma_16_table,
3435 int gamma_shift));
3436#endif
3437
3438#if defined(PNG_READ_EXPAND_SUPPORTED)
3439PNG_EXTERN void png_do_expand_palette PNGARG((png_row_infop row_info,
3440 png_bytep row, png_colorp palette, png_bytep trans, int num_trans));
3441PNG_EXTERN void png_do_expand PNGARG((png_row_infop row_info,
3442 png_bytep row, png_color_16p trans_value));
3443#endif
3444
3445/* The following decodes the appropriate chunks, and does error correction,
3446 * then calls the appropriate callback for the chunk if it is valid.
3447 */
3448
3449/* decode the IHDR chunk */
3450PNG_EXTERN void png_handle_IHDR PNGARG((png_structp png_ptr, png_infop info_ptr,
3451 png_uint_32 length));
3452PNG_EXTERN void png_handle_PLTE PNGARG((png_structp png_ptr, png_infop info_ptr,
3453 png_uint_32 length));
3454PNG_EXTERN void png_handle_IEND PNGARG((png_structp png_ptr, png_infop info_ptr,
3455 png_uint_32 length));
3456
3457#if defined(PNG_READ_bKGD_SUPPORTED)
3458PNG_EXTERN void png_handle_bKGD PNGARG((png_structp png_ptr, png_infop info_ptr,
3459 png_uint_32 length));
3460#endif
3461
3462#if defined(PNG_READ_cHRM_SUPPORTED)
3463PNG_EXTERN void png_handle_cHRM PNGARG((png_structp png_ptr, png_infop info_ptr,
3464 png_uint_32 length));
3465#endif
3466
3467#if defined(PNG_READ_gAMA_SUPPORTED)
3468PNG_EXTERN void png_handle_gAMA PNGARG((png_structp png_ptr, png_infop info_ptr,
3469 png_uint_32 length));
3470#endif
3471
3472#if defined(PNG_READ_hIST_SUPPORTED)
3473PNG_EXTERN void png_handle_hIST PNGARG((png_structp png_ptr, png_infop info_ptr,
3474 png_uint_32 length));
3475#endif
3476
3477#if defined(PNG_READ_iCCP_SUPPORTED)
3478extern void png_handle_iCCP PNGARG((png_structp png_ptr, png_infop info_ptr,
3479 png_uint_32 length));
3480#endif /* PNG_READ_iCCP_SUPPORTED */
3481
3482#if defined(PNG_READ_iTXt_SUPPORTED)
3483PNG_EXTERN void png_handle_iTXt PNGARG((png_structp png_ptr, png_infop info_ptr,
3484 png_uint_32 length));
3485#endif
3486
3487#if defined(PNG_READ_oFFs_SUPPORTED)
3488PNG_EXTERN void png_handle_oFFs PNGARG((png_structp png_ptr, png_infop info_ptr,
3489 png_uint_32 length));
3490#endif
3491
3492#if defined(PNG_READ_pCAL_SUPPORTED)
3493PNG_EXTERN void png_handle_pCAL PNGARG((png_structp png_ptr, png_infop info_ptr,
3494 png_uint_32 length));
3495#endif
3496
3497#if defined(PNG_READ_pHYs_SUPPORTED)
3498PNG_EXTERN void png_handle_pHYs PNGARG((png_structp png_ptr, png_infop info_ptr,
3499 png_uint_32 length));
3500#endif
3501
3502#if defined(PNG_READ_sBIT_SUPPORTED)
3503PNG_EXTERN void png_handle_sBIT PNGARG((png_structp png_ptr, png_infop info_ptr,
3504 png_uint_32 length));
3505#endif
3506
3507#if defined(PNG_READ_sCAL_SUPPORTED)
3508PNG_EXTERN void png_handle_sCAL PNGARG((png_structp png_ptr, png_infop info_ptr,
3509 png_uint_32 length));
3510#endif
3511
3512#if defined(PNG_READ_sPLT_SUPPORTED)
3513extern void png_handle_sPLT PNGARG((png_structp png_ptr, png_infop info_ptr,
3514 png_uint_32 length));
3515#endif /* PNG_READ_sPLT_SUPPORTED */
3516
3517#if defined(PNG_READ_sRGB_SUPPORTED)
3518PNG_EXTERN void png_handle_sRGB PNGARG((png_structp png_ptr, png_infop info_ptr,
3519 png_uint_32 length));
3520#endif
3521
3522#if defined(PNG_READ_tEXt_SUPPORTED)
3523PNG_EXTERN void png_handle_tEXt PNGARG((png_structp png_ptr, png_infop info_ptr,
3524 png_uint_32 length));
3525#endif
3526
3527#if defined(PNG_READ_tIME_SUPPORTED)
3528PNG_EXTERN void png_handle_tIME PNGARG((png_structp png_ptr, png_infop info_ptr,
3529 png_uint_32 length));
3530#endif
3531
3532#if defined(PNG_READ_tRNS_SUPPORTED)
3533PNG_EXTERN void png_handle_tRNS PNGARG((png_structp png_ptr, png_infop info_ptr,
3534 png_uint_32 length));
3535#endif
3536
3537#if defined(PNG_READ_zTXt_SUPPORTED)
3538PNG_EXTERN void png_handle_zTXt PNGARG((png_structp png_ptr, png_infop info_ptr,
3539 png_uint_32 length));
3540#endif
3541
3542PNG_EXTERN void png_handle_unknown PNGARG((png_structp png_ptr,
3543 png_infop info_ptr, png_uint_32 length));
3544
3545PNG_EXTERN void png_check_chunk_name PNGARG((png_structp png_ptr,
3546 png_bytep chunk_name));
3547
3548/* handle the transformations for reading and writing */
3549PNG_EXTERN void png_do_read_transformations PNGARG((png_structp png_ptr));
3550PNG_EXTERN void png_do_write_transformations PNGARG((png_structp png_ptr));
3551
3552PNG_EXTERN void png_init_read_transformations PNGARG((png_structp png_ptr));
3553
3554#ifdef PNG_PROGRESSIVE_READ_SUPPORTED
3555PNG_EXTERN void png_push_read_chunk PNGARG((png_structp png_ptr,
3556 png_infop info_ptr));
3557PNG_EXTERN void png_push_read_sig PNGARG((png_structp png_ptr,
3558 png_infop info_ptr));
3559PNG_EXTERN void png_push_check_crc PNGARG((png_structp png_ptr));
3560PNG_EXTERN void png_push_crc_skip PNGARG((png_structp png_ptr,
3561 png_uint_32 length));
3562PNG_EXTERN void png_push_crc_finish PNGARG((png_structp png_ptr));
3563PNG_EXTERN void png_push_save_buffer PNGARG((png_structp png_ptr));
3564PNG_EXTERN void png_push_restore_buffer PNGARG((png_structp png_ptr,
3565 png_bytep buffer, png_size_t buffer_length));
3566PNG_EXTERN void png_push_read_IDAT PNGARG((png_structp png_ptr));
3567PNG_EXTERN void png_process_IDAT_data PNGARG((png_structp png_ptr,
3568 png_bytep buffer, png_size_t buffer_length));
3569PNG_EXTERN void png_push_process_row PNGARG((png_structp png_ptr));
3570PNG_EXTERN void png_push_handle_unknown PNGARG((png_structp png_ptr,
3571 png_infop info_ptr, png_uint_32 length));
3572PNG_EXTERN void png_push_have_info PNGARG((png_structp png_ptr,
3573 png_infop info_ptr));
3574PNG_EXTERN void png_push_have_end PNGARG((png_structp png_ptr,
3575 png_infop info_ptr));
3576PNG_EXTERN void png_push_have_row PNGARG((png_structp png_ptr, png_bytep row));
3577PNG_EXTERN void png_push_read_end PNGARG((png_structp png_ptr,
3578 png_infop info_ptr));
3579PNG_EXTERN void png_process_some_data PNGARG((png_structp png_ptr,
3580 png_infop info_ptr));
3581PNG_EXTERN void png_read_push_finish_row PNGARG((png_structp png_ptr));
3582#if defined(PNG_READ_tEXt_SUPPORTED)
3583PNG_EXTERN void png_push_handle_tEXt PNGARG((png_structp png_ptr,
3584 png_infop info_ptr, png_uint_32 length));
3585PNG_EXTERN void png_push_read_tEXt PNGARG((png_structp png_ptr,
3586 png_infop info_ptr));
3587#endif
3588#if defined(PNG_READ_zTXt_SUPPORTED)
3589PNG_EXTERN void png_push_handle_zTXt PNGARG((png_structp png_ptr,
3590 png_infop info_ptr, png_uint_32 length));
3591PNG_EXTERN void png_push_read_zTXt PNGARG((png_structp png_ptr,
3592 png_infop info_ptr));
3593#endif
3594#if defined(PNG_READ_iTXt_SUPPORTED)
3595PNG_EXTERN void png_push_handle_iTXt PNGARG((png_structp png_ptr,
3596 png_infop info_ptr, png_uint_32 length));
3597PNG_EXTERN void png_push_read_iTXt PNGARG((png_structp png_ptr,
3598 png_infop info_ptr));
3599#endif
3600
3601#endif /* PNG_PROGRESSIVE_READ_SUPPORTED */
3602
3603#ifdef PNG_MNG_FEATURES_SUPPORTED
3604PNG_EXTERN void png_do_read_intrapixel PNGARG((png_row_infop row_info,
3605 png_bytep row));
3606PNG_EXTERN void png_do_write_intrapixel PNGARG((png_row_infop row_info,
3607 png_bytep row));
3608#endif
3609
3610#if defined(PNG_ASSEMBLER_CODE_SUPPORTED)
3611#if defined(PNG_MMX_CODE_SUPPORTED)
3612/* png.c */ /* PRIVATE */
3613PNG_EXTERN void png_init_mmx_flags PNGARG((png_structp png_ptr));
3614#endif
3615#endif
3616
3617#if defined(PNG_INCH_CONVERSIONS) && defined(PNG_FLOATING_POINT_SUPPORTED)
3618PNG_EXTERN png_uint_32 png_get_pixels_per_inch PNGARG((png_structp png_ptr,
3619png_infop info_ptr));
3620
3621PNG_EXTERN png_uint_32 png_get_x_pixels_per_inch PNGARG((png_structp png_ptr,
3622png_infop info_ptr));
3623
3624PNG_EXTERN png_uint_32 png_get_y_pixels_per_inch PNGARG((png_structp png_ptr,
3625png_infop info_ptr));
3626
3627PNG_EXTERN float png_get_x_offset_inches PNGARG((png_structp png_ptr,
3628png_infop info_ptr));
3629
3630PNG_EXTERN float png_get_y_offset_inches PNGARG((png_structp png_ptr,
3631png_infop info_ptr));
3632
3633#if defined(PNG_pHYs_SUPPORTED)
3634PNG_EXTERN png_uint_32 png_get_pHYs_dpi PNGARG((png_structp png_ptr,
3635png_infop info_ptr, png_uint_32 *res_x, png_uint_32 *res_y, int *unit_type));
3636#endif /* PNG_pHYs_SUPPORTED */
3637#endif /* PNG_INCH_CONVERSIONS && PNG_FLOATING_POINT_SUPPORTED */
3638
3639/* Read the chunk header (length + type name) */
3640PNG_EXTERN png_uint_32 png_read_chunk_header PNGARG((png_structp png_ptr));
3641
3642/* Added at libpng version 1.2.34 */
3643#if defined(PNG_cHRM_SUPPORTED)
3644PNG_EXTERN int png_check_cHRM_fixed PNGARG((png_structp png_ptr,
3645 png_fixed_point int_white_x, png_fixed_point int_white_y,
3646 png_fixed_point int_red_x, png_fixed_point int_red_y, png_fixed_point
3647 int_green_x, png_fixed_point int_green_y, png_fixed_point int_blue_x,
3648 png_fixed_point int_blue_y));
3649#endif
3650
3651/* Maintainer: Put new private prototypes here ^ and in libpngpf.3 */
3652
3653#endif /* PNG_INTERNAL */
3654
3655#ifdef __cplusplus
3656}
3657#endif
3658
3659#endif /* PNG_VERSION_INFO_ONLY */
3660/* do not put anything past this line */
3661#endif /* PNG_H */
wxWidgets (Impactor)