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1/* png.h - header file for PNG reference library
2 *
2b5f62a0 3 * libpng version 1.2.5rc3 - September 18, 2002
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4 * Copyright (c) 1998-2002 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.)
75b6e0a0 7 *
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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
2b5f62a0 11 * libpng versions 0.97, January 1998, through 1.2.5rc3 - September 18, 2002: Glenn
4946a942 12 * See also "Contributing Authors", below.
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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 *
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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
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96 * 1.2.5beta1-2 13 10205 12.so.0.1.2.5beta1-2
97 * 1.2.5rc1-3 13 10205 12.so.0.1.2.5rc1-3
98 * 1.0.15rc1-3 10 10015 10.so.0.1.0.15rc1-3
75b6e0a0 99 *
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100 * Henceforth the source version will match the shared-library major
101 * and minor numbers; the shared-library major version number will be
75b6e0a0 102 * used for changes in backward compatibility, as it is intended. The
4946a942 103 * PNG_LIBPNG_VER macro, which is not used within libpng but is available
75b6e0a0 104 * for applications, is an unsigned integer of the form xyyzz corresponding
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105 * to the source version x.y.z (leading zeros in y and z). Beta versions
106 * were given the previous public release number plus a letter, until
107 * version 1.0.6j; from then on they were given the upcoming public
108 * release number plus "betaNN" or "rcN".
109 *
110 * Binary incompatibility exists only when applications make direct access
111 * to the info_ptr or png_ptr members through png.h, and the compiled
112 * application is loaded with a different version of the library.
113 *
114 * DLLNUM will change each time there are forward or backward changes
115 * in binary compatibility (e.g., when a new feature is added).
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116 *
117 * See libpng.txt or libpng.3 for more information. The PNG specification
118 * is available as RFC 2083 <ftp://ftp.uu.net/graphics/png/documents/>
119 * and as a W3C Recommendation <http://www.w3.org/TR/REC.png.html>
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120 */
121
122/*
123 * COPYRIGHT NOTICE, DISCLAIMER, and LICENSE:
124 *
125 * If you modify libpng you may insert additional notices immediately following
126 * this sentence.
127 *
2b5f62a0 128 * libpng versions 1.0.7, July 1, 2000, through 1.2.5rc3, September 18, 2002, are
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129 * Copyright (c) 2000-2002 Glenn Randers-Pehrson, and are
130 * distributed according to the same disclaimer and license as libpng-1.0.6
131 * with the following individuals added to the list of Contributing Authors
132 *
133 * Simon-Pierre Cadieux
134 * Eric S. Raymond
135 * Gilles Vollant
136 *
137 * and with the following additions to the disclaimer:
138 *
139 * There is no warranty against interference with your enjoyment of the
140 * library or against infringement. There is no warranty that our
141 * efforts or the library will fulfill any of your particular purposes
142 * or needs. This library is provided with all faults, and the entire
143 * risk of satisfactory quality, performance, accuracy, and effort is with
144 * the user.
145 *
146 * libpng versions 0.97, January 1998, through 1.0.6, March 20, 2000, are
147 * Copyright (c) 1998, 1999, 2000 Glenn Randers-Pehrson
148 * Distributed according to the same disclaimer and license as libpng-0.96,
149 * with the following individuals added to the list of Contributing Authors:
150 *
151 * Tom Lane
152 * Glenn Randers-Pehrson
153 * Willem van Schaik
154 *
155 * libpng versions 0.89, June 1996, through 0.96, May 1997, are
156 * Copyright (c) 1996, 1997 Andreas Dilger
157 * Distributed according to the same disclaimer and license as libpng-0.88,
158 * with the following individuals added to the list of Contributing Authors:
75b6e0a0 159 *
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160 * John Bowler
161 * Kevin Bracey
162 * Sam Bushell
75b6e0a0 163 * Magnus Holmgren
75b6e0a0 164 * Greg Roelofs
75b6e0a0 165 * Tom Tanner
75b6e0a0 166 *
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167 * libpng versions 0.5, May 1995, through 0.88, January 1996, are
168 * Copyright (c) 1995, 1996 Guy Eric Schalnat, Group 42, Inc.
75b6e0a0 169 *
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170 * For the purposes of this copyright and license, "Contributing Authors"
171 * is defined as the following set of individuals:
75b6e0a0 172 *
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173 * Andreas Dilger
174 * Dave Martindale
175 * Guy Eric Schalnat
176 * Paul Schmidt
177 * Tim Wegner
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178 *
179 * The PNG Reference Library is supplied "AS IS". The Contributing Authors
180 * and Group 42, Inc. disclaim all warranties, expressed or implied,
181 * including, without limitation, the warranties of merchantability and of
182 * fitness for any purpose. The Contributing Authors and Group 42, Inc.
183 * assume no liability for direct, indirect, incidental, special, exemplary,
184 * or consequential damages, which may result from the use of the PNG
185 * Reference Library, even if advised of the possibility of such damage.
186 *
187 * Permission is hereby granted to use, copy, modify, and distribute this
188 * source code, or portions hereof, for any purpose, without fee, subject
189 * to the following restrictions:
4946a942 190 *
75b6e0a0 191 * 1. The origin of this source code must not be misrepresented.
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192 *
193 * 2. Altered versions must be plainly marked as such and
194 * must not be misrepresented as being the original source.
195 *
196 * 3. This Copyright notice may not be removed or altered from
197 * any source or altered source distribution.
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198 *
199 * The Contributing Authors and Group 42, Inc. specifically permit, without
200 * fee, and encourage the use of this source code as a component to
201 * supporting the PNG file format in commercial products. If you use this
202 * source code in a product, acknowledgment is not required but would be
203 * appreciated.
204 */
205
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206/*
207 * A "png_get_copyright" function is available, for convenient use in "about"
208 * boxes and the like:
209 *
210 * printf("%s",png_get_copyright(NULL));
211 *
212 * Also, the PNG logo (in PNG format, of course) is supplied in the
213 * files "pngbar.png" and "pngbar.jpg (88x31) and "pngnow.png" (98x31).
214 */
75b6e0a0 215
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216/*
217 * Libpng is OSI Certified Open Source Software. OSI Certified is a
218 * certification mark of the Open Source Initiative.
219 */
75b6e0a0 220
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221/*
222 * The contributing authors would like to thank all those who helped
223 * with testing, bug fixes, and patience. This wouldn't have been
224 * possible without all of you.
225 *
226 * Thanks to Frank J. T. Wojcik for helping with the documentation.
227 */
228
229/*
230 * Y2K compliance in libpng:
231 * =========================
232 *
2b5f62a0 233 * September 18, 2002
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234 *
235 * Since the PNG Development group is an ad-hoc body, we can't make
236 * an official declaration.
237 *
238 * This is your unofficial assurance that libpng from version 0.71 and
2b5f62a0 239 * upward through 1.2.5rc3 are Y2K compliant. It is my belief that earlier
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240 * versions were also Y2K compliant.
241 *
242 * Libpng only has three year fields. One is a 2-byte unsigned integer
243 * that will hold years up to 65535. The other two hold the date in text
244 * format, and will hold years up to 9999.
245 *
246 * The integer is
247 * "png_uint_16 year" in png_time_struct.
248 *
249 * The strings are
250 * "png_charp time_buffer" in png_struct and
251 * "near_time_buffer", which is a local character string in png.c.
252 *
253 * There are seven time-related functions:
254 * png.c: png_convert_to_rfc_1123() in png.c
255 * (formerly png_convert_to_rfc_1152() in error)
256 * png_convert_from_struct_tm() in pngwrite.c, called in pngwrite.c
257 * png_convert_from_time_t() in pngwrite.c
258 * png_get_tIME() in pngget.c
259 * png_handle_tIME() in pngrutil.c, called in pngread.c
260 * png_set_tIME() in pngset.c
261 * png_write_tIME() in pngwutil.c, called in pngwrite.c
262 *
263 * All handle dates properly in a Y2K environment. The
264 * png_convert_from_time_t() function calls gmtime() to convert from system
265 * clock time, which returns (year - 1900), which we properly convert to
266 * the full 4-digit year. There is a possibility that applications using
267 * libpng are not passing 4-digit years into the png_convert_to_rfc_1123()
268 * function, or that they are incorrectly passing only a 2-digit year
269 * instead of "year - 1900" into the png_convert_from_struct_tm() function,
270 * but this is not under our control. The libpng documentation has always
271 * stated that it works with 4-digit years, and the APIs have been
272 * documented as such.
273 *
274 * The tIME chunk itself is also Y2K compliant. It uses a 2-byte unsigned
275 * integer to hold the year, and can hold years as large as 65535.
276 *
277 * zlib, upon which libpng depends, is also Y2K compliant. It contains
278 * no date-related code.
279 *
280 * Glenn Randers-Pehrson
281 * libpng maintainer
282 * PNG Development Group
283 */
284
285#ifndef PNG_H
286#define PNG_H
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287
288/* This is not the place to learn how to use libpng. The file libpng.txt
289 * describes how to use libpng, and the file example.c summarizes it
290 * with some code on which to build. This file is useful for looking
291 * at the actual function definitions and structure components.
292 */
293
4946a942 294/* Version information for png.h - this should match the version in png.c */
2b5f62a0 295#define PNG_LIBPNG_VER_STRING "1.2.5rc3"
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296
297#define PNG_LIBPNG_VER_SONUM 0
298#define PNG_LIBPNG_VER_DLLNUM %DLLNUM%
299
300/* These should match the first 3 components of PNG_LIBPNG_VER_STRING: */
301#define PNG_LIBPNG_VER_MAJOR 1
302#define PNG_LIBPNG_VER_MINOR 2
2b5f62a0 303#define PNG_LIBPNG_VER_RELEASE 5
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304/* This should match the numeric part of the final component of
305 * PNG_LIBPNG_VER_STRING, omitting any leading zero: */
306
2b5f62a0 307#define PNG_LIBPNG_VER_BUILD 3
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308
309#define PNG_LIBPNG_BUILD_ALPHA 1
310#define PNG_LIBPNG_BUILD_BETA 2
311#define PNG_LIBPNG_BUILD_RC 3
312#define PNG_LIBPNG_BUILD_STABLE 4
313#define PNG_LIBPNG_BUILD_TYPEMASK 7
314#define PNG_LIBPNG_BUILD_PATCH 8 /* Can be OR'ed with STABLE only */
2b5f62a0 315#define PNG_LIBPNG_BUILD_TYPE 3
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316
317/* Careful here. At one time, Guy wanted to use 082, but that would be octal.
318 * We must not include leading zeros.
319 * Versions 0.7 through 1.0.0 were in the range 0 to 100 here (only
320 * version 1.0.0 was mis-numbered 100 instead of 10000). From
321 * version 1.0.1 it's xxyyzz, where x=major, y=minor, z=release */
2b5f62a0 322#define PNG_LIBPNG_VER 10205 /* 1.2.5 */
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323
324#ifndef PNG_VERSION_INFO_ONLY
325
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326/* include the compression library's header */
327#include "zlib.h"
328
4946a942 329/* include all user configurable info, including optional assembler routines */
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330#include "pngconf.h"
331
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332/* Inhibit C++ name-mangling for libpng functions but not for system calls. */
333#ifdef __cplusplus
334extern "C" {
335#endif /* __cplusplus */
336
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337/* This file is arranged in several sections. The first section contains
338 * structure and type definitions. The second section contains the external
339 * library functions, while the third has the internal library functions,
340 * which applications aren't expected to use directly.
341 */
342
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343#ifndef PNG_NO_TYPECAST_NULL
344#define int_p_NULL (int *)NULL
345#define png_bytep_NULL (png_bytep)NULL
346#define png_bytepp_NULL (png_bytepp)NULL
347#define png_doublep_NULL (png_doublep)NULL
348#define png_error_ptr_NULL (png_error_ptr)NULL
349#define png_flush_ptr_NULL (png_flush_ptr)NULL
350#define png_free_ptr_NULL (png_free_ptr)NULL
351#define png_infopp_NULL (png_infopp)NULL
352#define png_malloc_ptr_NULL (png_malloc_ptr)NULL
353#define png_read_status_ptr_NULL (png_read_status_ptr)NULL
354#define png_rw_ptr_NULL (png_rw_ptr)NULL
355#define png_structp_NULL (png_structp)NULL
356#define png_uint_16p_NULL (png_uint_16p)NULL
357#define png_voidp_NULL (png_voidp)NULL
358#define png_write_status_ptr_NULL (png_write_status_ptr)NULL
359#else
360#define int_p_NULL NULL
361#define png_bytep_NULL NULL
362#define png_bytepp_NULL NULL
363#define png_doublep_NULL NULL
364#define png_error_ptr_NULL NULL
365#define png_flush_ptr_NULL NULL
366#define png_free_ptr_NULL NULL
367#define png_infopp_NULL NULL
368#define png_malloc_ptr_NULL NULL
369#define png_read_status_ptr_NULL NULL
370#define png_rw_ptr_NULL NULL
371#define png_structp_NULL NULL
372#define png_uint_16p_NULL NULL
373#define png_voidp_NULL NULL
374#define png_write_status_ptr_NULL NULL
375#endif
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376
377/* variables declared in png.c - only it needs to define PNG_NO_EXTERN */
378#if !defined(PNG_NO_EXTERN) || defined(PNG_ALWAYS_EXTERN)
379/* Version information for C files, stored in png.c. This had better match
380 * the version above.
381 */
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382#ifdef PNG_USE_GLOBAL_ARRAYS
383PNG_EXPORT_VAR (const char) png_libpng_ver[18];
384 /* need room for 99.99.99beta99z */
385#else
386#define png_libpng_ver png_get_header_ver(NULL)
387#endif
75b6e0a0 388
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389#ifdef PNG_USE_GLOBAL_ARRAYS
390/* This was removed in version 1.0.5c */
75b6e0a0 391/* Structures to facilitate easy interlacing. See png.c for more details */
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392PNG_EXPORT_VAR (const int FARDATA) png_pass_start[7];
393PNG_EXPORT_VAR (const int FARDATA) png_pass_inc[7];
394PNG_EXPORT_VAR (const int FARDATA) png_pass_ystart[7];
395PNG_EXPORT_VAR (const int FARDATA) png_pass_yinc[7];
396PNG_EXPORT_VAR (const int FARDATA) png_pass_mask[7];
397PNG_EXPORT_VAR (const int FARDATA) png_pass_dsp_mask[7];
398#ifdef PNG_HAVE_ASSEMBLER_COMBINE_ROW
399PNG_EXPORT_VAR (const int FARDATA) png_pass_width[7];
400#endif
401/* This isn't currently used. If you need it, see png.c for more details.
402PNG_EXPORT_VAR (const int FARDATA) png_pass_height[7];
75b6e0a0 403*/
4946a942 404#endif
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405
406#endif /* PNG_NO_EXTERN */
407
408/* Three color definitions. The order of the red, green, and blue, (and the
409 * exact size) is not important, although the size of the fields need to
410 * be png_byte or png_uint_16 (as defined below).
411 */
412typedef struct png_color_struct
413{
414 png_byte red;
415 png_byte green;
416 png_byte blue;
417} png_color;
418typedef png_color FAR * png_colorp;
419typedef png_color FAR * FAR * png_colorpp;
420
421typedef struct png_color_16_struct
422{
423 png_byte index; /* used for palette files */
424 png_uint_16 red; /* for use in red green blue files */
425 png_uint_16 green;
426 png_uint_16 blue;
427 png_uint_16 gray; /* for use in grayscale files */
428} png_color_16;
429typedef png_color_16 FAR * png_color_16p;
430typedef png_color_16 FAR * FAR * png_color_16pp;
431
432typedef struct png_color_8_struct
433{
434 png_byte red; /* for use in red green blue files */
435 png_byte green;
436 png_byte blue;
437 png_byte gray; /* for use in grayscale files */
438 png_byte alpha; /* for alpha channel files */
439} png_color_8;
440typedef png_color_8 FAR * png_color_8p;
441typedef png_color_8 FAR * FAR * png_color_8pp;
442
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443/*
444 * The following two structures are used for the in-core representation
445 * of sPLT chunks.
446 */
447typedef struct png_sPLT_entry_struct
448{
449 png_uint_16 red;
450 png_uint_16 green;
451 png_uint_16 blue;
452 png_uint_16 alpha;
453 png_uint_16 frequency;
454} png_sPLT_entry;
455typedef png_sPLT_entry FAR * png_sPLT_entryp;
456typedef png_sPLT_entry FAR * FAR * png_sPLT_entrypp;
457
458/* When the depth of the sPLT palette is 8 bits, the color and alpha samples
459 * occupy the LSB of their respective members, and the MSB of each member
460 * is zero-filled. The frequency member always occupies the full 16 bits.
461 */
462
463typedef struct png_sPLT_struct
464{
465 png_charp name; /* palette name */
466 png_byte depth; /* depth of palette samples */
467 png_sPLT_entryp entries; /* palette entries */
468 png_int_32 nentries; /* number of palette entries */
469} png_sPLT_t;
470typedef png_sPLT_t FAR * png_sPLT_tp;
471typedef png_sPLT_t FAR * FAR * png_sPLT_tpp;
472
473#ifdef PNG_TEXT_SUPPORTED
474/* png_text holds the contents of a text/ztxt/itxt chunk in a PNG file,
475 * and whether that contents is compressed or not. The "key" field
476 * points to a regular zero-terminated C string. The "text", "lang", and
477 * "lang_key" fields can be regular C strings, empty strings, or NULL pointers.
478 * However, the * structure returned by png_get_text() will always contain
479 * regular zero-terminated C strings (possibly empty), never NULL pointers,
480 * so they can be safely used in printf() and other string-handling functions.
481 */
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482typedef struct png_text_struct
483{
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484 int compression; /* compression value:
485 -1: tEXt, none
486 0: zTXt, deflate
487 1: iTXt, none
488 2: iTXt, deflate */
75b6e0a0 489 png_charp key; /* keyword, 1-79 character description of "text" */
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490 png_charp text; /* comment, may be an empty string (ie "")
491 or a NULL pointer */
492 png_size_t text_length; /* length of the text string */
493#ifdef PNG_iTXt_SUPPORTED
494 png_size_t itxt_length; /* length of the itxt string */
495 png_charp lang; /* language code, 0-79 characters
496 or a NULL pointer */
497 png_charp lang_key; /* keyword translated UTF-8 string, 0 or more
498 chars or a NULL pointer */
499#endif
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500} png_text;
501typedef png_text FAR * png_textp;
502typedef png_text FAR * FAR * png_textpp;
4946a942 503#endif
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504
505/* Supported compression types for text in PNG files (tEXt, and zTXt).
506 * The values of the PNG_TEXT_COMPRESSION_ defines should NOT be changed. */
507#define PNG_TEXT_COMPRESSION_NONE_WR -3
508#define PNG_TEXT_COMPRESSION_zTXt_WR -2
509#define PNG_TEXT_COMPRESSION_NONE -1
510#define PNG_TEXT_COMPRESSION_zTXt 0
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511#define PNG_ITXT_COMPRESSION_NONE 1
512#define PNG_ITXT_COMPRESSION_zTXt 2
513#define PNG_TEXT_COMPRESSION_LAST 3 /* Not a valid value */
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514
515/* png_time is a way to hold the time in an machine independent way.
516 * Two conversions are provided, both from time_t and struct tm. There
517 * is no portable way to convert to either of these structures, as far
518 * as I know. If you know of a portable way, send it to me. As a side
4946a942 519 * note - PNG has always been Year 2000 compliant!
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520 */
521typedef struct png_time_struct
522{
523 png_uint_16 year; /* full year, as in, 1995 */
524 png_byte month; /* month of year, 1 - 12 */
525 png_byte day; /* day of month, 1 - 31 */
526 png_byte hour; /* hour of day, 0 - 23 */
527 png_byte minute; /* minute of hour, 0 - 59 */
528 png_byte second; /* second of minute, 0 - 60 (for leap seconds) */
529} png_time;
530typedef png_time FAR * png_timep;
531typedef png_time FAR * FAR * png_timepp;
532
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533#if defined(PNG_UNKNOWN_CHUNKS_SUPPORTED)
534/* png_unknown_chunk is a structure to hold queued chunks for which there is
535 * no specific support. The idea is that we can use this to queue
536 * up private chunks for output even though the library doesn't actually
537 * know about their semantics.
538 */
539typedef struct png_unknown_chunk_t
540{
541 png_byte name[5];
542 png_byte *data;
543 png_size_t size;
544
545 /* libpng-using applications should NOT directly modify this byte. */
546 png_byte location; /* mode of operation at read time */
547}
548png_unknown_chunk;
549typedef png_unknown_chunk FAR * png_unknown_chunkp;
550typedef png_unknown_chunk FAR * FAR * png_unknown_chunkpp;
551#endif
552
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553/* png_info is a structure that holds the information in a PNG file so
554 * that the application can find out the characteristics of the image.
555 * If you are reading the file, this structure will tell you what is
556 * in the PNG file. If you are writing the file, fill in the information
557 * you want to put into the PNG file, then call png_write_info().
558 * The names chosen should be very close to the PNG specification, so
559 * consult that document for information about the meaning of each field.
560 *
561 * With libpng < 0.95, it was only possible to directly set and read the
562 * the values in the png_info_struct, which meant that the contents and
563 * order of the values had to remain fixed. With libpng 0.95 and later,
564 * however, there are now functions that abstract the contents of
565 * png_info_struct from the application, so this makes it easier to use
566 * libpng with dynamic libraries, and even makes it possible to use
567 * libraries that don't have all of the libpng ancillary chunk-handing
568 * functionality.
569 *
570 * In any case, the order of the parameters in png_info_struct should NOT
571 * be changed for as long as possible to keep compatibility with applications
572 * that use the old direct-access method with png_info_struct.
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573 *
574 * The following members may have allocated storage attached that should be
575 * cleaned up before the structure is discarded: palette, trans, text,
576 * pcal_purpose, pcal_units, pcal_params, hist, iccp_name, iccp_profile,
577 * splt_palettes, scal_unit, row_pointers, and unknowns. By default, these
578 * are automatically freed when the info structure is deallocated, if they were
579 * allocated internally by libpng. This behavior can be changed by means
580 * of the png_data_freer() function.
581 *
582 * More allocation details: all the chunk-reading functions that
583 * change these members go through the corresponding png_set_*
584 * functions. A function to clear these members is available: see
585 * png_free_data(). The png_set_* functions do not depend on being
586 * able to point info structure members to any of the storage they are
587 * passed (they make their own copies), EXCEPT that the png_set_text
588 * functions use the same storage passed to them in the text_ptr or
589 * itxt_ptr structure argument, and the png_set_rows and png_set_unknowns
590 * functions do not make their own copies.
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591 */
592typedef struct png_info_struct
593{
594 /* the following are necessary for every PNG file */
595 png_uint_32 width; /* width of image in pixels (from IHDR) */
596 png_uint_32 height; /* height of image in pixels (from IHDR) */
597 png_uint_32 valid; /* valid chunk data (see PNG_INFO_ below) */
598 png_uint_32 rowbytes; /* bytes needed to hold an untransformed row */
599 png_colorp palette; /* array of color values (valid & PNG_INFO_PLTE) */
600 png_uint_16 num_palette; /* number of color entries in "palette" (PLTE) */
601 png_uint_16 num_trans; /* number of transparent palette color (tRNS) */
602 png_byte bit_depth; /* 1, 2, 4, 8, or 16 bits/channel (from IHDR) */
603 png_byte color_type; /* see PNG_COLOR_TYPE_ below (from IHDR) */
4946a942 604 /* The following three should have been named *_method not *_type */
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605 png_byte compression_type; /* must be PNG_COMPRESSION_TYPE_BASE (IHDR) */
606 png_byte filter_type; /* must be PNG_FILTER_TYPE_BASE (from IHDR) */
607 png_byte interlace_type; /* One of PNG_INTERLACE_NONE, PNG_INTERLACE_ADAM7 */
608
609 /* The following is informational only on read, and not used on writes. */
4946a942 610 png_byte channels; /* number of data channels per pixel (1, 2, 3, 4) */
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611 png_byte pixel_depth; /* number of bits per pixel */
612 png_byte spare_byte; /* to align the data, and for future use */
613 png_byte signature[8]; /* magic bytes read by libpng from start of file */
614
615 /* The rest of the data is optional. If you are reading, check the
616 * valid field to see if the information in these are valid. If you
617 * are writing, set the valid field to those chunks you want written,
618 * and initialize the appropriate fields below.
619 */
620
4946a942 621#if defined(PNG_gAMA_SUPPORTED) && defined(PNG_FLOATING_POINT_SUPPORTED)
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622 /* The gAMA chunk describes the gamma characteristics of the system
623 * on which the image was created, normally in the range [1.0, 2.5].
624 * Data is valid if (valid & PNG_INFO_gAMA) is non-zero.
625 */
626 float gamma; /* gamma value of image, if (valid & PNG_INFO_gAMA) */
4946a942 627#endif
75b6e0a0 628
4946a942 629#if defined(PNG_sRGB_SUPPORTED)
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630 /* GR-P, 0.96a */
631 /* Data valid if (valid & PNG_INFO_sRGB) non-zero. */
632 png_byte srgb_intent; /* sRGB rendering intent [0, 1, 2, or 3] */
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633#endif
634
635#if defined(PNG_TEXT_SUPPORTED)
636 /* The tEXt, and zTXt chunks contain human-readable textual data in
637 * uncompressed, compressed, and optionally compressed forms, respectively.
638 * The data in "text" is an array of pointers to uncompressed,
639 * null-terminated C strings. Each chunk has a keyword that describes the
640 * textual data contained in that chunk. Keywords are not required to be
641 * unique, and the text string may be empty. Any number of text chunks may
642 * be in an image.
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643 */
644 int num_text; /* number of comments read/to write */
645 int max_text; /* current size of text array */
646 png_textp text; /* array of comments read/to write */
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647#endif /* PNG_TEXT_SUPPORTED */
648
649#if defined(PNG_tIME_SUPPORTED)
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650 /* The tIME chunk holds the last time the displayed image data was
651 * modified. See the png_time struct for the contents of this struct.
652 */
653 png_time mod_time;
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654#endif
655
656#if defined(PNG_sBIT_SUPPORTED)
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657 /* The sBIT chunk specifies the number of significant high-order bits
658 * in the pixel data. Values are in the range [1, bit_depth], and are
659 * only specified for the channels in the pixel data. The contents of
660 * the low-order bits is not specified. Data is valid if
661 * (valid & PNG_INFO_sBIT) is non-zero.
662 */
663 png_color_8 sig_bit; /* significant bits in color channels */
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664#endif
665
666#if defined(PNG_tRNS_SUPPORTED) || defined(PNG_READ_EXPAND_SUPPORTED) || \
667defined(PNG_READ_BACKGROUND_SUPPORTED)
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668 /* The tRNS chunk supplies transparency data for paletted images and
669 * other image types that don't need a full alpha channel. There are
670 * "num_trans" transparency values for a paletted image, stored in the
671 * same order as the palette colors, starting from index 0. Values
672 * for the data are in the range [0, 255], ranging from fully transparent
673 * to fully opaque, respectively. For non-paletted images, there is a
674 * single color specified that should be treated as fully transparent.
675 * Data is valid if (valid & PNG_INFO_tRNS) is non-zero.
676 */
677 png_bytep trans; /* transparent values for paletted image */
678 png_color_16 trans_values; /* transparent color for non-palette image */
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679#endif
680
681#if defined(PNG_bKGD_SUPPORTED) || defined(PNG_READ_BACKGROUND_SUPPORTED)
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682 /* The bKGD chunk gives the suggested image background color if the
683 * display program does not have its own background color and the image
684 * is needs to composited onto a background before display. The colors
685 * in "background" are normally in the same color space/depth as the
686 * pixel data. Data is valid if (valid & PNG_INFO_bKGD) is non-zero.
687 */
688 png_color_16 background;
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689#endif
690
691#if defined(PNG_oFFs_SUPPORTED)
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692 /* The oFFs chunk gives the offset in "offset_unit_type" units rightwards
693 * and downwards from the top-left corner of the display, page, or other
694 * application-specific co-ordinate space. See the PNG_OFFSET_ defines
695 * below for the unit types. Valid if (valid & PNG_INFO_oFFs) non-zero.
696 */
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697 png_int_32 x_offset; /* x offset on page */
698 png_int_32 y_offset; /* y offset on page */
75b6e0a0 699 png_byte offset_unit_type; /* offset units type */
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700#endif
701
702#if defined(PNG_pHYs_SUPPORTED)
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703 /* The pHYs chunk gives the physical pixel density of the image for
704 * display or printing in "phys_unit_type" units (see PNG_RESOLUTION_
705 * defines below). Data is valid if (valid & PNG_INFO_pHYs) is non-zero.
706 */
707 png_uint_32 x_pixels_per_unit; /* horizontal pixel density */
708 png_uint_32 y_pixels_per_unit; /* vertical pixel density */
709 png_byte phys_unit_type; /* resolution type (see PNG_RESOLUTION_ below) */
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710#endif
711
712#if defined(PNG_hIST_SUPPORTED)
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713 /* The hIST chunk contains the relative frequency or importance of the
714 * various palette entries, so that a viewer can intelligently select a
715 * reduced-color palette, if required. Data is an array of "num_palette"
716 * values in the range [0,65535]. Data valid if (valid & PNG_INFO_hIST)
717 * is non-zero.
718 */
719 png_uint_16p hist;
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720#endif
721
722#ifdef PNG_cHRM_SUPPORTED
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723 /* The cHRM chunk describes the CIE color characteristics of the monitor
724 * on which the PNG was created. This data allows the viewer to do gamut
725 * mapping of the input image to ensure that the viewer sees the same
726 * colors in the image as the creator. Values are in the range
727 * [0.0, 0.8]. Data valid if (valid & PNG_INFO_cHRM) non-zero.
728 */
4946a942 729#ifdef PNG_FLOATING_POINT_SUPPORTED
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730 float x_white;
731 float y_white;
732 float x_red;
733 float y_red;
734 float x_green;
735 float y_green;
736 float x_blue;
737 float y_blue;
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738#endif
739#endif
740
741#if defined(PNG_pCAL_SUPPORTED)
75b6e0a0 742 /* The pCAL chunk describes a transformation between the stored pixel
4946a942 743 * values and original physical data values used to create the image.
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744 * The integer range [0, 2^bit_depth - 1] maps to the floating-point
745 * range given by [pcal_X0, pcal_X1], and are further transformed by a
746 * (possibly non-linear) transformation function given by "pcal_type"
747 * and "pcal_params" into "pcal_units". Please see the PNG_EQUATION_
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748 * defines below, and the PNG-Group's PNG extensions document for a
749 * complete description of the transformations and how they should be
750 * implemented, and for a description of the ASCII parameter strings.
751 * Data values are valid if (valid & PNG_INFO_pCAL) non-zero.
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752 */
753 png_charp pcal_purpose; /* pCAL chunk description string */
754 png_int_32 pcal_X0; /* minimum value */
755 png_int_32 pcal_X1; /* maximum value */
756 png_charp pcal_units; /* Latin-1 string giving physical units */
757 png_charpp pcal_params; /* ASCII strings containing parameter values */
758 png_byte pcal_type; /* equation type (see PNG_EQUATION_ below) */
759 png_byte pcal_nparams; /* number of parameters given in pcal_params */
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760#endif
761
762/* New members added in libpng-1.0.6 */
763#ifdef PNG_FREE_ME_SUPPORTED
764 png_uint_32 free_me; /* flags items libpng is responsible for freeing */
765#endif
766
767#if defined(PNG_UNKNOWN_CHUNKS_SUPPORTED)
768 /* storage for unknown chunks that the library doesn't recognize. */
769 png_unknown_chunkp unknown_chunks;
770 png_size_t unknown_chunks_num;
771#endif
772
773#if defined(PNG_iCCP_SUPPORTED)
774 /* iCCP chunk data. */
775 png_charp iccp_name; /* profile name */
776 png_charp iccp_profile; /* International Color Consortium profile data */
777 /* Note to maintainer: should be png_bytep */
778 png_uint_32 iccp_proflen; /* ICC profile data length */
779 png_byte iccp_compression; /* Always zero */
780#endif
781
782#if defined(PNG_sPLT_SUPPORTED)
783 /* data on sPLT chunks (there may be more than one). */
784 png_sPLT_tp splt_palettes;
785 png_uint_32 splt_palettes_num;
786#endif
787
788#if defined(PNG_sCAL_SUPPORTED)
789 /* The sCAL chunk describes the actual physical dimensions of the
790 * subject matter of the graphic. The chunk contains a unit specification
791 * a byte value, and two ASCII strings representing floating-point
792 * values. The values are width and height corresponsing to one pixel
793 * in the image. This external representation is converted to double
794 * here. Data values are valid if (valid & PNG_INFO_sCAL) is non-zero.
795 */
796 png_byte scal_unit; /* unit of physical scale */
797#ifdef PNG_FLOATING_POINT_SUPPORTED
798 double scal_pixel_width; /* width of one pixel */
799 double scal_pixel_height; /* height of one pixel */
800#endif
801#ifdef PNG_FIXED_POINT_SUPPORTED
802 png_charp scal_s_width; /* string containing height */
803 png_charp scal_s_height; /* string containing width */
804#endif
805#endif
806
807#if defined(PNG_INFO_IMAGE_SUPPORTED)
808 /* Memory has been allocated if (valid & PNG_ALLOCATED_INFO_ROWS) non-zero */
809 /* Data valid if (valid & PNG_INFO_IDAT) non-zero */
810 png_bytepp row_pointers; /* the image bits */
811#endif
812
813#if defined(PNG_FIXED_POINT_SUPPORTED) && defined(PNG_gAMA_SUPPORTED)
814 png_fixed_point int_gamma; /* gamma of image, if (valid & PNG_INFO_gAMA) */
815#endif
816
817#if defined(PNG_cHRM_SUPPORTED) && defined(PNG_FIXED_POINT_SUPPORTED)
818 png_fixed_point int_x_white;
819 png_fixed_point int_y_white;
820 png_fixed_point int_x_red;
821 png_fixed_point int_y_red;
822 png_fixed_point int_x_green;
823 png_fixed_point int_y_green;
824 png_fixed_point int_x_blue;
825 png_fixed_point int_y_blue;
826#endif
827
75b6e0a0 828} png_info;
4946a942 829
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830typedef png_info FAR * png_infop;
831typedef png_info FAR * FAR * png_infopp;
832
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833/* Maximum positive integer used in PNG is (2^31)-1 */
834#define PNG_MAX_UINT ((png_uint_32)0x7fffffffL)
835
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836/* These describe the color_type field in png_info. */
837/* color type masks */
838#define PNG_COLOR_MASK_PALETTE 1
839#define PNG_COLOR_MASK_COLOR 2
840#define PNG_COLOR_MASK_ALPHA 4
841
842/* color types. Note that not all combinations are legal */
843#define PNG_COLOR_TYPE_GRAY 0
844#define PNG_COLOR_TYPE_PALETTE (PNG_COLOR_MASK_COLOR | PNG_COLOR_MASK_PALETTE)
845#define PNG_COLOR_TYPE_RGB (PNG_COLOR_MASK_COLOR)
846#define PNG_COLOR_TYPE_RGB_ALPHA (PNG_COLOR_MASK_COLOR | PNG_COLOR_MASK_ALPHA)
847#define PNG_COLOR_TYPE_GRAY_ALPHA (PNG_COLOR_MASK_ALPHA)
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848/* aliases */
849#define PNG_COLOR_TYPE_RGBA PNG_COLOR_TYPE_RGB_ALPHA
850#define PNG_COLOR_TYPE_GA PNG_COLOR_TYPE_GRAY_ALPHA
75b6e0a0 851
4946a942 852/* This is for compression type. PNG 1.0-1.2 only define the single type. */
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853#define PNG_COMPRESSION_TYPE_BASE 0 /* Deflate method 8, 32K window */
854#define PNG_COMPRESSION_TYPE_DEFAULT PNG_COMPRESSION_TYPE_BASE
855
4946a942 856/* This is for filter type. PNG 1.0-1.2 only define the single type. */
75b6e0a0 857#define PNG_FILTER_TYPE_BASE 0 /* Single row per-byte filtering */
4946a942 858#define PNG_INTRAPIXEL_DIFFERENCING 64 /* Used only in MNG datastreams */
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859#define PNG_FILTER_TYPE_DEFAULT PNG_FILTER_TYPE_BASE
860
861/* These are for the interlacing type. These values should NOT be changed. */
862#define PNG_INTERLACE_NONE 0 /* Non-interlaced image */
863#define PNG_INTERLACE_ADAM7 1 /* Adam7 interlacing */
864#define PNG_INTERLACE_LAST 2 /* Not a valid value */
865
866/* These are for the oFFs chunk. These values should NOT be changed. */
867#define PNG_OFFSET_PIXEL 0 /* Offset in pixels */
868#define PNG_OFFSET_MICROMETER 1 /* Offset in micrometers (1/10^6 meter) */
869#define PNG_OFFSET_LAST 2 /* Not a valid value */
870
871/* These are for the pCAL chunk. These values should NOT be changed. */
872#define PNG_EQUATION_LINEAR 0 /* Linear transformation */
873#define PNG_EQUATION_BASE_E 1 /* Exponential base e transform */
874#define PNG_EQUATION_ARBITRARY 2 /* Arbitrary base exponential transform */
875#define PNG_EQUATION_HYPERBOLIC 3 /* Hyperbolic sine transformation */
876#define PNG_EQUATION_LAST 4 /* Not a valid value */
877
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878/* These are for the sCAL chunk. These values should NOT be changed. */
879#define PNG_SCALE_UNKNOWN 0 /* unknown unit (image scale) */
880#define PNG_SCALE_METER 1 /* meters per pixel */
881#define PNG_SCALE_RADIAN 2 /* radians per pixel */
882#define PNG_SCALE_LAST 3 /* Not a valid value */
883
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884/* These are for the pHYs chunk. These values should NOT be changed. */
885#define PNG_RESOLUTION_UNKNOWN 0 /* pixels/unknown unit (aspect ratio) */
886#define PNG_RESOLUTION_METER 1 /* pixels/meter */
887#define PNG_RESOLUTION_LAST 2 /* Not a valid value */
888
889/* These are for the sRGB chunk. These values should NOT be changed. */
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890#define PNG_sRGB_INTENT_PERCEPTUAL 0
891#define PNG_sRGB_INTENT_RELATIVE 1
892#define PNG_sRGB_INTENT_SATURATION 2
893#define PNG_sRGB_INTENT_ABSOLUTE 3
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894#define PNG_sRGB_INTENT_LAST 4 /* Not a valid value */
895
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896/* This is for text chunks */
897#define PNG_KEYWORD_MAX_LENGTH 79
75b6e0a0 898
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899/* Maximum number of entries in PLTE/sPLT/tRNS arrays */
900#define PNG_MAX_PALETTE_LENGTH 256
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901
902/* These determine if an ancillary chunk's data has been successfully read
903 * from the PNG header, or if the application has filled in the corresponding
904 * data in the info_struct to be written into the output file. The values
905 * of the PNG_INFO_<chunk> defines should NOT be changed.
906 */
907#define PNG_INFO_gAMA 0x0001
908#define PNG_INFO_sBIT 0x0002
909#define PNG_INFO_cHRM 0x0004
910#define PNG_INFO_PLTE 0x0008
911#define PNG_INFO_tRNS 0x0010
912#define PNG_INFO_bKGD 0x0020
913#define PNG_INFO_hIST 0x0040
914#define PNG_INFO_pHYs 0x0080
915#define PNG_INFO_oFFs 0x0100
916#define PNG_INFO_tIME 0x0200
917#define PNG_INFO_pCAL 0x0400
918#define PNG_INFO_sRGB 0x0800 /* GR-P, 0.96a */
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919#define PNG_INFO_iCCP 0x1000 /* ESR, 1.0.6 */
920#define PNG_INFO_sPLT 0x2000 /* ESR, 1.0.6 */
921#define PNG_INFO_sCAL 0x4000 /* ESR, 1.0.6 */
922#define PNG_INFO_IDAT 0x8000L /* ESR, 1.0.6 */
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923
924/* This is used for the transformation routines, as some of them
925 * change these values for the row. It also should enable using
926 * the routines for other purposes.
927 */
928typedef struct png_row_info_struct
929{
930 png_uint_32 width; /* width of row */
931 png_uint_32 rowbytes; /* number of bytes in row */
932 png_byte color_type; /* color type of row */
933 png_byte bit_depth; /* bit depth of row */
934 png_byte channels; /* number of channels (1, 2, 3, or 4) */
935 png_byte pixel_depth; /* bits per pixel (depth * channels) */
936} png_row_info;
937
938typedef png_row_info FAR * png_row_infop;
939typedef png_row_info FAR * FAR * png_row_infopp;
940
941/* These are the function types for the I/O functions and for the functions
942 * that allow the user to override the default I/O functions with his or her
943 * own. The png_error_ptr type should match that of user-supplied warning
944 * and error functions, while the png_rw_ptr type should match that of the
945 * user read/write data functions.
946 */
947typedef struct png_struct_def png_struct;
948typedef png_struct FAR * png_structp;
949
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950typedef void (PNGAPI *png_error_ptr) PNGARG((png_structp, png_const_charp));
951typedef void (PNGAPI *png_rw_ptr) PNGARG((png_structp, png_bytep, png_size_t));
952typedef void (PNGAPI *png_flush_ptr) PNGARG((png_structp));
953typedef void (PNGAPI *png_read_status_ptr) PNGARG((png_structp, png_uint_32,
954 int));
955typedef void (PNGAPI *png_write_status_ptr) PNGARG((png_structp, png_uint_32,
956 int));
957
75b6e0a0 958#ifdef PNG_PROGRESSIVE_READ_SUPPORTED
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959typedef void (PNGAPI *png_progressive_info_ptr) PNGARG((png_structp, png_infop));
960typedef void (PNGAPI *png_progressive_end_ptr) PNGARG((png_structp, png_infop));
961typedef void (PNGAPI *png_progressive_row_ptr) PNGARG((png_structp, png_bytep,
75b6e0a0 962 png_uint_32, int));
4946a942 963#endif
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964
965#if defined(PNG_READ_USER_TRANSFORM_SUPPORTED) || \
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966 defined(PNG_WRITE_USER_TRANSFORM_SUPPORTED) || \
967 defined(PNG_LEGACY_SUPPORTED)
968typedef void (PNGAPI *png_user_transform_ptr) PNGARG((png_structp,
75b6e0a0 969 png_row_infop, png_bytep));
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970#endif
971
972#if defined(PNG_USER_CHUNKS_SUPPORTED)
973typedef int (PNGAPI *png_user_chunk_ptr) PNGARG((png_structp, png_unknown_chunkp));
974#endif
975#if defined(PNG_UNKNOWN_CHUNKS_SUPPORTED)
976typedef void (PNGAPI *png_unknown_chunk_ptr) PNGARG((png_structp));
977#endif
978
979/* Transform masks for the high-level interface */
980#define PNG_TRANSFORM_IDENTITY 0x0000 /* read and write */
981#define PNG_TRANSFORM_STRIP_16 0x0001 /* read only */
982#define PNG_TRANSFORM_STRIP_ALPHA 0x0002 /* read only */
983#define PNG_TRANSFORM_PACKING 0x0004 /* read and write */
984#define PNG_TRANSFORM_PACKSWAP 0x0008 /* read and write */
985#define PNG_TRANSFORM_EXPAND 0x0010 /* read only */
986#define PNG_TRANSFORM_INVERT_MONO 0x0020 /* read and write */
987#define PNG_TRANSFORM_SHIFT 0x0040 /* read and write */
988#define PNG_TRANSFORM_BGR 0x0080 /* read and write */
989#define PNG_TRANSFORM_SWAP_ALPHA 0x0100 /* read and write */
990#define PNG_TRANSFORM_SWAP_ENDIAN 0x0200 /* read and write */
991#define PNG_TRANSFORM_INVERT_ALPHA 0x0400 /* read and write */
992#define PNG_TRANSFORM_STRIP_FILLER 0x0800 /* WRITE only */
993
994/* Flags for MNG supported features */
995#define PNG_FLAG_MNG_EMPTY_PLTE 0x01
996#define PNG_FLAG_MNG_FILTER_64 0x04
997#define PNG_ALL_MNG_FEATURES 0x05
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998
999typedef png_voidp (*png_malloc_ptr) PNGARG((png_structp, png_size_t));
4946a942 1000typedef void (*png_free_ptr) PNGARG((png_structp, png_voidp));
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1001
1002/* The structure that holds the information to read and write PNG files.
1003 * The only people who need to care about what is inside of this are the
1004 * people who will be modifying the library for their own special needs.
1005 * It should NOT be accessed directly by an application, except to store
1006 * the jmp_buf.
1007 */
1008
1009struct png_struct_def
1010{
4946a942 1011#ifdef PNG_SETJMP_SUPPORTED
75b6e0a0 1012 jmp_buf jmpbuf; /* used in png_error */
4946a942 1013#endif
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1014 png_error_ptr error_fn; /* function for printing errors and aborting */
1015 png_error_ptr warning_fn; /* function for printing warnings */
1016 png_voidp error_ptr; /* user supplied struct for error functions */
1017 png_rw_ptr write_data_fn; /* function for writing output data */
1018 png_rw_ptr read_data_fn; /* function for reading input data */
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1019 png_voidp io_ptr; /* ptr to application struct for I/O functions */
1020
1021#if defined(PNG_READ_USER_TRANSFORM_SUPPORTED)
75b6e0a0 1022 png_user_transform_ptr read_user_transform_fn; /* user read transform */
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1023#endif
1024
1025#if defined(PNG_WRITE_USER_TRANSFORM_SUPPORTED)
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1026 png_user_transform_ptr write_user_transform_fn; /* user write transform */
1027#endif
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1028
1029/* These were added in libpng-1.0.2 */
1030#if defined(PNG_USER_TRANSFORM_PTR_SUPPORTED)
1031#if defined(PNG_READ_USER_TRANSFORM_SUPPORTED) || \
1032 defined(PNG_WRITE_USER_TRANSFORM_SUPPORTED)
1033 png_voidp user_transform_ptr; /* user supplied struct for user transform */
1034 png_byte user_transform_depth; /* bit depth of user transformed pixels */
1035 png_byte user_transform_channels; /* channels in user transformed pixels */
1036#endif
1037#endif
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1038
1039 png_uint_32 mode; /* tells us where we are in the PNG file */
1040 png_uint_32 flags; /* flags indicating various things to libpng */
1041 png_uint_32 transformations; /* which transformations to perform */
1042
1043 z_stream zstream; /* pointer to decompression structure (below) */
1044 png_bytep zbuf; /* buffer for zlib */
1045 png_size_t zbuf_size; /* size of zbuf */
1046 int zlib_level; /* holds zlib compression level */
1047 int zlib_method; /* holds zlib compression method */
1048 int zlib_window_bits; /* holds zlib compression window bits */
1049 int zlib_mem_level; /* holds zlib compression memory level */
1050 int zlib_strategy; /* holds zlib compression strategy */
1051
1052 png_uint_32 width; /* width of image in pixels */
1053 png_uint_32 height; /* height of image in pixels */
1054 png_uint_32 num_rows; /* number of rows in current pass */
1055 png_uint_32 usr_width; /* width of row at start of write */
1056 png_uint_32 rowbytes; /* size of row in bytes */
1057 png_uint_32 irowbytes; /* size of current interlaced row in bytes */
1058 png_uint_32 iwidth; /* width of current interlaced row in pixels */
1059 png_uint_32 row_number; /* current row in interlace pass */
1060 png_bytep prev_row; /* buffer to save previous (unfiltered) row */
1061 png_bytep row_buf; /* buffer to save current (unfiltered) row */
1062 png_bytep sub_row; /* buffer to save "sub" row when filtering */
1063 png_bytep up_row; /* buffer to save "up" row when filtering */
1064 png_bytep avg_row; /* buffer to save "avg" row when filtering */
1065 png_bytep paeth_row; /* buffer to save "Paeth" row when filtering */
1066 png_row_info row_info; /* used for transformation routines */
1067
1068 png_uint_32 idat_size; /* current IDAT size for read */
1069 png_uint_32 crc; /* current chunk CRC value */
1070 png_colorp palette; /* palette from the input file */
1071 png_uint_16 num_palette; /* number of color entries in palette */
1072 png_uint_16 num_trans; /* number of transparency values */
1073 png_byte chunk_name[5]; /* null-terminated name of current chunk */
1074 png_byte compression; /* file compression type (always 0) */
1075 png_byte filter; /* file filter type (always 0) */
1076 png_byte interlaced; /* PNG_INTERLACE_NONE, PNG_INTERLACE_ADAM7 */
1077 png_byte pass; /* current interlace pass (0 - 6) */
1078 png_byte do_filter; /* row filter flags (see PNG_FILTER_ below ) */
1079 png_byte color_type; /* color type of file */
1080 png_byte bit_depth; /* bit depth of file */
1081 png_byte usr_bit_depth; /* bit depth of users row */
1082 png_byte pixel_depth; /* number of bits per pixel */
1083 png_byte channels; /* number of channels in file */
1084 png_byte usr_channels; /* channels at start of write */
1085 png_byte sig_bytes; /* magic bytes read/written from start of file */
1086
1087#if defined(PNG_READ_FILLER_SUPPORTED) || defined(PNG_WRITE_FILLER_SUPPORTED)
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1088#ifdef PNG_LEGACY_SUPPORTED
1089 png_byte filler; /* filler byte for pixel expansion */
1090#else
75b6e0a0 1091 png_uint_16 filler; /* filler bytes for pixel expansion */
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1092#endif
1093#endif
1094
1095#if defined(PNG_bKGD_SUPPORTED)
75b6e0a0 1096 png_byte background_gamma_type;
4946a942 1097# ifdef PNG_FLOATING_POINT_SUPPORTED
75b6e0a0 1098 float background_gamma;
4946a942 1099# endif
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1100 png_color_16 background; /* background color in screen gamma space */
1101#if defined(PNG_READ_GAMMA_SUPPORTED)
1102 png_color_16 background_1; /* background normalized to gamma 1.0 */
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1103#endif
1104#endif /* PNG_bKGD_SUPPORTED */
1105
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1106#if defined(PNG_WRITE_FLUSH_SUPPORTED)
1107 png_flush_ptr output_flush_fn;/* Function for flushing output */
1108 png_uint_32 flush_dist; /* how many rows apart to flush, 0 - no flush */
1109 png_uint_32 flush_rows; /* number of rows written since last flush */
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1110#endif
1111
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1112#if defined(PNG_READ_GAMMA_SUPPORTED) || defined(PNG_READ_BACKGROUND_SUPPORTED)
1113 int gamma_shift; /* number of "insignificant" bits 16-bit gamma */
4946a942 1114#ifdef PNG_FLOATING_POINT_SUPPORTED
75b6e0a0 1115 float gamma; /* file gamma value */
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1116 float screen_gamma; /* screen gamma value (display_exponent) */
1117#endif
1118#endif
1119
75b6e0a0 1120#if defined(PNG_READ_GAMMA_SUPPORTED) || defined(PNG_READ_BACKGROUND_SUPPORTED)
4946a942 1121 png_bytep gamma_table; /* gamma table for 8-bit depth files */
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1122 png_bytep gamma_from_1; /* converts from 1.0 to screen */
1123 png_bytep gamma_to_1; /* converts from file to 1.0 */
4946a942 1124 png_uint_16pp gamma_16_table; /* gamma table for 16-bit depth files */
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1125 png_uint_16pp gamma_16_from_1; /* converts from 1.0 to screen */
1126 png_uint_16pp gamma_16_to_1; /* converts from file to 1.0 */
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1127#endif
1128
1129#if defined(PNG_READ_GAMMA_SUPPORTED) || defined(PNG_sBIT_SUPPORTED)
75b6e0a0 1130 png_color_8 sig_bit; /* significant bits in each available channel */
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1131#endif
1132
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1133#if defined(PNG_READ_SHIFT_SUPPORTED) || defined(PNG_WRITE_SHIFT_SUPPORTED)
1134 png_color_8 shift; /* shift for significant bit tranformation */
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1135#endif
1136
1137#if defined(PNG_tRNS_SUPPORTED) || defined(PNG_READ_BACKGROUND_SUPPORTED) \
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1138 || defined(PNG_READ_EXPAND_SUPPORTED) || defined(PNG_READ_BACKGROUND_SUPPORTED)
1139 png_bytep trans; /* transparency values for paletted files */
1140 png_color_16 trans_values; /* transparency values for non-paletted files */
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1141#endif
1142
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1143 png_read_status_ptr read_row_fn; /* called after each row is decoded */
1144 png_write_status_ptr write_row_fn; /* called after each row is encoded */
1145#ifdef PNG_PROGRESSIVE_READ_SUPPORTED
1146 png_progressive_info_ptr info_fn; /* called after header data fully read */
1147 png_progressive_row_ptr row_fn; /* called after each prog. row is decoded */
1148 png_progressive_end_ptr end_fn; /* called after image is complete */
1149 png_bytep save_buffer_ptr; /* current location in save_buffer */
1150 png_bytep save_buffer; /* buffer for previously read data */
1151 png_bytep current_buffer_ptr; /* current location in current_buffer */
1152 png_bytep current_buffer; /* buffer for recently used data */
1153 png_uint_32 push_length; /* size of current input chunk */
1154 png_uint_32 skip_length; /* bytes to skip in input data */
1155 png_size_t save_buffer_size; /* amount of data now in save_buffer */
1156 png_size_t save_buffer_max; /* total size of save_buffer */
1157 png_size_t buffer_size; /* total amount of available input data */
1158 png_size_t current_buffer_size; /* amount of data now in current_buffer */
1159 int process_mode; /* what push library is currently doing */
1160 int cur_palette; /* current push library palette index */
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1161
1162# if defined(PNG_TEXT_SUPPORTED)
1163 png_size_t current_text_size; /* current size of text input data */
1164 png_size_t current_text_left; /* how much text left to read in input */
1165 png_charp current_text; /* current text chunk buffer */
1166 png_charp current_text_ptr; /* current location in current_text */
1167# endif /* PNG_PROGRESSIVE_READ_SUPPORTED && PNG_TEXT_SUPPORTED */
1168
75b6e0a0 1169#endif /* PNG_PROGRESSIVE_READ_SUPPORTED */
4946a942 1170
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1171#if defined(__TURBOC__) && !defined(_Windows) && !defined(__FLAT__)
1172/* for the Borland special 64K segment handler */
1173 png_bytepp offset_table_ptr;
1174 png_bytep offset_table;
1175 png_uint_16 offset_table_number;
1176 png_uint_16 offset_table_count;
1177 png_uint_16 offset_table_count_free;
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1178#endif
1179
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1180#if defined(PNG_READ_DITHER_SUPPORTED)
1181 png_bytep palette_lookup; /* lookup table for dithering */
1182 png_bytep dither_index; /* index translation for palette files */
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1183#endif
1184
1185#if defined(PNG_READ_DITHER_SUPPORTED) || defined(PNG_hIST_SUPPORTED)
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1186 png_uint_16p hist; /* histogram */
1187#endif
4946a942 1188
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1189#if defined(PNG_WRITE_WEIGHTED_FILTER_SUPPORTED)
1190 png_byte heuristic_method; /* heuristic for row filter selection */
1191 png_byte num_prev_filters; /* number of weights for previous rows */
1192 png_bytep prev_filters; /* filter type(s) of previous row(s) */
1193 png_uint_16p filter_weights; /* weight(s) for previous line(s) */
1194 png_uint_16p inv_filter_weights; /* 1/weight(s) for previous line(s) */
1195 png_uint_16p filter_costs; /* relative filter calculation cost */
1196 png_uint_16p inv_filter_costs; /* 1/relative filter calculation cost */
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1197#endif
1198
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1199#if defined(PNG_TIME_RFC1123_SUPPORTED)
1200 png_charp time_buffer; /* String to hold RFC 1123 time text */
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1201#endif
1202
1203/* New members added in libpng-1.0.6 */
1204
1205#ifdef PNG_FREE_ME_SUPPORTED
1206 png_uint_32 free_me; /* flags items libpng is responsible for freeing */
1207#endif
1208
1209#if defined(PNG_USER_CHUNKS_SUPPORTED)
1210 png_voidp user_chunk_ptr;
1211 png_user_chunk_ptr read_user_chunk_fn; /* user read chunk handler */
1212#endif
1213
1214#if defined(PNG_UNKNOWN_CHUNKS_SUPPORTED)
1215 int num_chunk_list;
1216 png_bytep chunk_list;
1217#endif
1218
1219/* New members added in libpng-1.0.3 */
1220#if defined(PNG_READ_RGB_TO_GRAY_SUPPORTED)
1221 png_byte rgb_to_gray_status;
1222 /* These were changed from png_byte in libpng-1.0.6 */
1223 png_uint_16 rgb_to_gray_red_coeff;
1224 png_uint_16 rgb_to_gray_green_coeff;
1225 png_uint_16 rgb_to_gray_blue_coeff;
1226#endif
1227
1228/* New member added in libpng-1.0.4 (renamed in 1.0.9) */
1229#if defined(PNG_MNG_FEATURES_SUPPORTED) || \
1230 defined(PNG_READ_EMPTY_PLTE_SUPPORTED) || \
1231 defined(PNG_WRITE_EMPTY_PLTE_SUPPORTED)
1232/* changed from png_byte to png_uint_32 at version 1.2.0 */
1233#ifdef PNG_1_0_X
1234 png_byte mng_features_permitted;
1235#else
1236 png_uint_32 mng_features_permitted;
1237#endif /* PNG_1_0_X */
1238#endif
1239
1240/* New member added in libpng-1.0.7 */
1241#if defined(PNG_READ_GAMMA_SUPPORTED) || defined(PNG_READ_BACKGROUND_SUPPORTED)
1242 png_fixed_point int_gamma;
1243#endif
1244
1245/* New member added in libpng-1.0.9, ifdef'ed out in 1.0.12, enabled in 1.2.0 */
1246#if defined(PNG_MNG_FEATURES_SUPPORTED)
1247 png_byte filter_type;
1248#endif
1249
1250#if defined(PNG_1_0_X) || (defined(PNG_DEBUG) && defined(PNG_USE_PNGGCCRD))
1251/* New member added in libpng-1.0.10, ifdef'ed out in 1.2.0 */
1252 png_uint_32 row_buf_size;
1253#endif
1254
1255/* New members added in libpng-1.2.0 */
1256#if !defined(PNG_1_0_X) && defined(PNG_ASSEMBLER_CODE_SUPPORTED)
1257 png_byte mmx_bitdepth_threshold;
1258 png_uint_32 mmx_rowbytes_threshold;
1259 png_uint_32 asm_flags;
1260#endif
1261
1262/* New members added in libpng-1.0.2 but first enabled by default in 1.2.0 */
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1263#ifdef PNG_USER_MEM_SUPPORTED
1264 png_voidp mem_ptr; /* user supplied struct for mem functions */
1265 png_malloc_ptr malloc_fn; /* function for allocating memory */
1266 png_free_ptr free_fn; /* function for freeing memory */
75b6e0a0 1267#endif
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1268
1269/* New member added in libpng-1.0.13 and 1.2.0 */
1270 png_bytep big_row_buf; /* buffer to save current (unfiltered) row */
1271
1272#if defined(PNG_READ_DITHER_SUPPORTED)
1273/* The following three members were added at version 1.0.14 and 1.2.4 */
1274 png_bytep dither_sort; /* working sort array */
1275 png_bytep index_to_palette; /* where the original index currently is */
1276 /* in the palette */
1277 png_bytep palette_to_index; /* which original index points to this */
1278 /* palette color */
1279#endif
1280
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1281};
1282
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1283
1284/* This prevents a compiler error in png.c if png.c and png.h are both at
2b5f62a0 1285 version 1.2.5rc3
4946a942 1286 */
2b5f62a0 1287typedef png_structp version_1_2_5rc3;
4946a942 1288
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1289typedef png_struct FAR * FAR * png_structpp;
1290
1291/* Here are the function definitions most commonly used. This is not
1292 * the place to find out how to use libpng. See libpng.txt for the
1293 * full explanation, see example.c for the summary. This just provides
4946a942 1294 * a simple one line description of the use of each function.
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1295 */
1296
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1297/* Returns the version number of the library */
1298extern PNG_EXPORT(png_uint_32,png_access_version_number) PNGARG((void));
1299
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1300/* Tell lib we have already handled the first <num_bytes> magic bytes.
1301 * Handling more than 8 bytes from the beginning of the file is an error.
1302 */
1303extern PNG_EXPORT(void,png_set_sig_bytes) PNGARG((png_structp png_ptr,
1304 int num_bytes));
1305
1306/* Check sig[start] through sig[start + num_to_check - 1] to see if it's a
1307 * PNG file. Returns zero if the supplied bytes match the 8-byte PNG
1308 * signature, and non-zero otherwise. Having num_to_check == 0 or
1309 * start > 7 will always fail (ie return non-zero).
1310 */
1311extern PNG_EXPORT(int,png_sig_cmp) PNGARG((png_bytep sig, png_size_t start,
1312 png_size_t num_to_check));
1313
1314/* Simple signature checking function. This is the same as calling
1315 * png_check_sig(sig, n) := !png_sig_cmp(sig, 0, n).
1316 */
1317extern PNG_EXPORT(int,png_check_sig) PNGARG((png_bytep sig, int num));
1318
1319/* Allocate and initialize png_ptr struct for reading, and any other memory. */
1320extern PNG_EXPORT(png_structp,png_create_read_struct)
1321 PNGARG((png_const_charp user_png_ver, png_voidp error_ptr,
1322 png_error_ptr error_fn, png_error_ptr warn_fn));
1323
1324/* Allocate and initialize png_ptr struct for writing, and any other memory */
1325extern PNG_EXPORT(png_structp,png_create_write_struct)
1326 PNGARG((png_const_charp user_png_ver, png_voidp error_ptr,
1327 png_error_ptr error_fn, png_error_ptr warn_fn));
1328
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1329extern PNG_EXPORT(png_uint_32,png_get_compression_buffer_size)
1330 PNGARG((png_structp png_ptr));
1331
1332extern PNG_EXPORT(void,png_set_compression_buffer_size)
1333 PNGARG((png_structp png_ptr, png_uint_32 size));
1334
1335/* Reset the compression stream */
1336extern PNG_EXPORT(int,png_reset_zstream) PNGARG((png_structp png_ptr));
1337
1338/* New functions added in libpng-1.0.2 (not enabled by default until 1.2.0) */
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1339#ifdef PNG_USER_MEM_SUPPORTED
1340extern PNG_EXPORT(png_structp,png_create_read_struct_2)
1341 PNGARG((png_const_charp user_png_ver, png_voidp error_ptr,
1342 png_error_ptr error_fn, png_error_ptr warn_fn, png_voidp mem_ptr,
1343 png_malloc_ptr malloc_fn, png_free_ptr free_fn));
1344extern PNG_EXPORT(png_structp,png_create_write_struct_2)
1345 PNGARG((png_const_charp user_png_ver, png_voidp error_ptr,
1346 png_error_ptr error_fn, png_error_ptr warn_fn, png_voidp mem_ptr,
1347 png_malloc_ptr malloc_fn, png_free_ptr free_fn));
1348#endif
1349
1350/* Write a PNG chunk - size, type, (optional) data, CRC. */
1351extern PNG_EXPORT(void,png_write_chunk) PNGARG((png_structp png_ptr,
1352 png_bytep chunk_name, png_bytep data, png_size_t length));
1353
1354/* Write the start of a PNG chunk - length and chunk name. */
1355extern PNG_EXPORT(void,png_write_chunk_start) PNGARG((png_structp png_ptr,
1356 png_bytep chunk_name, png_uint_32 length));
1357
1358/* Write the data of a PNG chunk started with png_write_chunk_start(). */
1359extern PNG_EXPORT(void,png_write_chunk_data) PNGARG((png_structp png_ptr,
1360 png_bytep data, png_size_t length));
1361
1362/* Finish a chunk started with png_write_chunk_start() (includes CRC). */
1363extern PNG_EXPORT(void,png_write_chunk_end) PNGARG((png_structp png_ptr));
1364
1365/* Allocate and initialize the info structure */
1366extern PNG_EXPORT(png_infop,png_create_info_struct)
1367 PNGARG((png_structp png_ptr));
1368
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1369/* Initialize the info structure (old interface - DEPRECATED) */
1370extern PNG_EXPORT(void,png_info_init) PNGARG((png_infop info_ptr));
1371#undef png_info_init
1372#define png_info_init(info_ptr) png_info_init_3(&info_ptr, sizeof(png_info));
1373extern PNG_EXPORT(void,png_info_init_3) PNGARG((png_infopp info_ptr,
1374 png_size_t png_info_struct_size));
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1375
1376/* Writes all the PNG information before the image. */
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1377extern PNG_EXPORT(void,png_write_info_before_PLTE) PNGARG((png_structp png_ptr,
1378 png_infop info_ptr));
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1379extern PNG_EXPORT(void,png_write_info) PNGARG((png_structp png_ptr,
1380 png_infop info_ptr));
1381
1382/* read the information before the actual image data. */
1383extern PNG_EXPORT(void,png_read_info) PNGARG((png_structp png_ptr,
1384 png_infop info_ptr));
1385
1386#if defined(PNG_TIME_RFC1123_SUPPORTED)
1387extern PNG_EXPORT(png_charp,png_convert_to_rfc1123)
1388 PNGARG((png_structp png_ptr, png_timep ptime));
4946a942 1389#endif
75b6e0a0 1390
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1391#if !defined(_WIN32_WCE)
1392/* "time.h" functions are not supported on WindowsCE */
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1393#if defined(PNG_WRITE_tIME_SUPPORTED)
1394/* convert from a struct tm to png_time */
1395extern PNG_EXPORT(void,png_convert_from_struct_tm) PNGARG((png_timep ptime,
1396 struct tm FAR * ttime));
1397
1398/* convert from time_t to png_time. Uses gmtime() */
1399extern PNG_EXPORT(void,png_convert_from_time_t) PNGARG((png_timep ptime,
1400 time_t ttime));
1401#endif /* PNG_WRITE_tIME_SUPPORTED */
4946a942 1402#endif /* _WIN32_WCE */
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1403
1404#if defined(PNG_READ_EXPAND_SUPPORTED)
4946a942 1405/* Expand data to 24-bit RGB, or 8-bit grayscale, with alpha if available. */
75b6e0a0 1406extern PNG_EXPORT(void,png_set_expand) PNGARG((png_structp png_ptr));
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1407extern PNG_EXPORT(void,png_set_gray_1_2_4_to_8) PNGARG((png_structp png_ptr));
1408extern PNG_EXPORT(void,png_set_palette_to_rgb) PNGARG((png_structp png_ptr));
1409extern PNG_EXPORT(void,png_set_tRNS_to_alpha) PNGARG((png_structp png_ptr));
1410#endif
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1411
1412#if defined(PNG_READ_BGR_SUPPORTED) || defined(PNG_WRITE_BGR_SUPPORTED)
1413/* Use blue, green, red order for pixels. */
1414extern PNG_EXPORT(void,png_set_bgr) PNGARG((png_structp png_ptr));
4946a942 1415#endif
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1416
1417#if defined(PNG_READ_GRAY_TO_RGB_SUPPORTED)
4946a942 1418/* Expand the grayscale to 24-bit RGB if necessary. */
75b6e0a0 1419extern PNG_EXPORT(void,png_set_gray_to_rgb) PNGARG((png_structp png_ptr));
4946a942 1420#endif
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1421
1422#if defined(PNG_READ_RGB_TO_GRAY_SUPPORTED)
1423/* Reduce RGB to grayscale. */
4946a942 1424#ifdef PNG_FLOATING_POINT_SUPPORTED
75b6e0a0 1425extern PNG_EXPORT(void,png_set_rgb_to_gray) PNGARG((png_structp png_ptr,
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1426 int error_action, double red, double green ));
1427#endif
1428extern PNG_EXPORT(void,png_set_rgb_to_gray_fixed) PNGARG((png_structp png_ptr,
1429 int error_action, png_fixed_point red, png_fixed_point green ));
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1430extern PNG_EXPORT(png_byte,png_get_rgb_to_gray_status) PNGARG((png_structp
1431 png_ptr));
4946a942 1432#endif
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1433
1434extern PNG_EXPORT(void,png_build_grayscale_palette) PNGARG((int bit_depth,
1435 png_colorp palette));
1436
1437#if defined(PNG_READ_STRIP_ALPHA_SUPPORTED)
1438extern PNG_EXPORT(void,png_set_strip_alpha) PNGARG((png_structp png_ptr));
4946a942 1439#endif
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1440
1441#if defined(PNG_READ_SWAP_ALPHA_SUPPORTED) || \
1442 defined(PNG_WRITE_SWAP_ALPHA_SUPPORTED)
1443extern PNG_EXPORT(void,png_set_swap_alpha) PNGARG((png_structp png_ptr));
4946a942 1444#endif
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1445
1446#if defined(PNG_READ_INVERT_ALPHA_SUPPORTED) || \
1447 defined(PNG_WRITE_INVERT_ALPHA_SUPPORTED)
1448extern PNG_EXPORT(void,png_set_invert_alpha) PNGARG((png_structp png_ptr));
4946a942 1449#endif
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1450
1451#if defined(PNG_READ_FILLER_SUPPORTED) || defined(PNG_WRITE_FILLER_SUPPORTED)
1452/* Add a filler byte to 24-bit RGB images. */
1453extern PNG_EXPORT(void,png_set_filler) PNGARG((png_structp png_ptr,
1454 png_uint_32 filler, int flags));
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1455/* The values of the PNG_FILLER_ defines should NOT be changed */
1456#define PNG_FILLER_BEFORE 0
1457#define PNG_FILLER_AFTER 1
1458#endif /* PNG_READ_FILLER_SUPPORTED || PNG_WRITE_FILLER_SUPPORTED */
1459
1460#if defined(PNG_READ_SWAP_SUPPORTED) || defined(PNG_WRITE_SWAP_SUPPORTED)
4946a942 1461/* Swap bytes in 16-bit depth files. */
75b6e0a0 1462extern PNG_EXPORT(void,png_set_swap) PNGARG((png_structp png_ptr));
4946a942 1463#endif
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1464
1465#if defined(PNG_READ_PACK_SUPPORTED) || defined(PNG_WRITE_PACK_SUPPORTED)
4946a942 1466/* Use 1 byte per pixel in 1, 2, or 4-bit depth files. */
75b6e0a0 1467extern PNG_EXPORT(void,png_set_packing) PNGARG((png_structp png_ptr));
4946a942 1468#endif
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1469
1470#if defined(PNG_READ_PACKSWAP_SUPPORTED) || defined(PNG_WRITE_PACKSWAP_SUPPORTED)
1471/* Swap packing order of pixels in bytes. */
1472extern PNG_EXPORT(void,png_set_packswap) PNGARG((png_structp png_ptr));
4946a942 1473#endif
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1474
1475#if defined(PNG_READ_SHIFT_SUPPORTED) || defined(PNG_WRITE_SHIFT_SUPPORTED)
1476/* Converts files to legal bit depths. */
1477extern PNG_EXPORT(void,png_set_shift) PNGARG((png_structp png_ptr,
1478 png_color_8p true_bits));
4946a942 1479#endif
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1480
1481#if defined(PNG_READ_INTERLACING_SUPPORTED) || \
1482 defined(PNG_WRITE_INTERLACING_SUPPORTED)
1483/* Have the code handle the interlacing. Returns the number of passes. */
1484extern PNG_EXPORT(int,png_set_interlace_handling) PNGARG((png_structp png_ptr));
4946a942 1485#endif
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1486
1487#if defined(PNG_READ_INVERT_SUPPORTED) || defined(PNG_WRITE_INVERT_SUPPORTED)
4946a942 1488/* Invert monochrome files */
75b6e0a0 1489extern PNG_EXPORT(void,png_set_invert_mono) PNGARG((png_structp png_ptr));
4946a942 1490#endif
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1491
1492#if defined(PNG_READ_BACKGROUND_SUPPORTED)
1493/* Handle alpha and tRNS by replacing with a background color. */
4946a942 1494#ifdef PNG_FLOATING_POINT_SUPPORTED
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1495extern PNG_EXPORT(void,png_set_background) PNGARG((png_structp png_ptr,
1496 png_color_16p background_color, int background_gamma_code,
1497 int need_expand, double background_gamma));
4946a942 1498#endif
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1499#define PNG_BACKGROUND_GAMMA_UNKNOWN 0
1500#define PNG_BACKGROUND_GAMMA_SCREEN 1
1501#define PNG_BACKGROUND_GAMMA_FILE 2
1502#define PNG_BACKGROUND_GAMMA_UNIQUE 3
4946a942 1503#endif
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1504
1505#if defined(PNG_READ_16_TO_8_SUPPORTED)
4946a942 1506/* strip the second byte of information from a 16-bit depth file. */
75b6e0a0 1507extern PNG_EXPORT(void,png_set_strip_16) PNGARG((png_structp png_ptr));
4946a942 1508#endif
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1509
1510#if defined(PNG_READ_DITHER_SUPPORTED)
1511/* Turn on dithering, and reduce the palette to the number of colors available. */
1512extern PNG_EXPORT(void,png_set_dither) PNGARG((png_structp png_ptr,
1513 png_colorp palette, int num_palette, int maximum_colors,
1514 png_uint_16p histogram, int full_dither));
4946a942 1515#endif
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1516
1517#if defined(PNG_READ_GAMMA_SUPPORTED)
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1518/* Handle gamma correction. Screen_gamma=(display_exponent) */
1519#ifdef PNG_FLOATING_POINT_SUPPORTED
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1520extern PNG_EXPORT(void,png_set_gamma) PNGARG((png_structp png_ptr,
1521 double screen_gamma, double default_file_gamma));
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1522#endif
1523#endif
1524
1525#if defined(PNG_READ_EMPTY_PLTE_SUPPORTED) || \
1526 defined(PNG_WRITE_EMPTY_PLTE_SUPPORTED)
1527/* Permit or disallow empty PLTE (0: not permitted, 1: permitted) */
1528/* Deprecated and will be removed. Use png_permit_mng_features() instead. */
1529extern PNG_EXPORT(void,png_permit_empty_plte) PNGARG((png_structp png_ptr,
1530 int empty_plte_permitted));
1531#endif
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1532
1533#if defined(PNG_WRITE_FLUSH_SUPPORTED)
1534/* Set how many lines between output flushes - 0 for no flushing */
1535extern PNG_EXPORT(void,png_set_flush) PNGARG((png_structp png_ptr, int nrows));
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1536/* Flush the current PNG output buffer */
1537extern PNG_EXPORT(void,png_write_flush) PNGARG((png_structp png_ptr));
4946a942 1538#endif
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1539
1540/* optional update palette with requested transformations */
1541extern PNG_EXPORT(void,png_start_read_image) PNGARG((png_structp png_ptr));
1542
1543/* optional call to update the users info structure */
1544extern PNG_EXPORT(void,png_read_update_info) PNGARG((png_structp png_ptr,
1545 png_infop info_ptr));
1546
4946a942 1547/* read one or more rows of image data. */
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1548extern PNG_EXPORT(void,png_read_rows) PNGARG((png_structp png_ptr,
1549 png_bytepp row, png_bytepp display_row, png_uint_32 num_rows));
1550
4946a942 1551/* read a row of data. */
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1552extern PNG_EXPORT(void,png_read_row) PNGARG((png_structp png_ptr,
1553 png_bytep row,
1554 png_bytep display_row));
1555
1556/* read the whole image into memory at once. */
1557extern PNG_EXPORT(void,png_read_image) PNGARG((png_structp png_ptr,
1558 png_bytepp image));
1559
1560/* write a row of image data */
1561extern PNG_EXPORT(void,png_write_row) PNGARG((png_structp png_ptr,
1562 png_bytep row));
1563
1564/* write a few rows of image data */
1565extern PNG_EXPORT(void,png_write_rows) PNGARG((png_structp png_ptr,
1566 png_bytepp row, png_uint_32 num_rows));
1567
1568/* write the image data */
1569extern PNG_EXPORT(void,png_write_image) PNGARG((png_structp png_ptr,
1570 png_bytepp image));
1571
1572/* writes the end of the PNG file. */
1573extern PNG_EXPORT(void,png_write_end) PNGARG((png_structp png_ptr,
1574 png_infop info_ptr));
1575
1576/* read the end of the PNG file. */
1577extern PNG_EXPORT(void,png_read_end) PNGARG((png_structp png_ptr,
1578 png_infop info_ptr));
1579
1580/* free any memory associated with the png_info_struct */
1581extern PNG_EXPORT(void,png_destroy_info_struct) PNGARG((png_structp png_ptr,
1582 png_infopp info_ptr_ptr));
1583
1584/* free any memory associated with the png_struct and the png_info_structs */
1585extern PNG_EXPORT(void,png_destroy_read_struct) PNGARG((png_structpp
1586 png_ptr_ptr, png_infopp info_ptr_ptr, png_infopp end_info_ptr_ptr));
1587
1588/* free all memory used by the read (old method - NOT DLL EXPORTED) */
1589extern void png_read_destroy PNGARG((png_structp png_ptr, png_infop info_ptr,
1590 png_infop end_info_ptr));
1591
1592/* free any memory associated with the png_struct and the png_info_structs */
1593extern PNG_EXPORT(void,png_destroy_write_struct)
1594 PNGARG((png_structpp png_ptr_ptr, png_infopp info_ptr_ptr));
1595
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1596/* free any memory used in png_ptr struct (old method - NOT DLL EXPORTED) */
1597extern void png_write_destroy PNGARG((png_structp png_ptr));
1598
1599/* set the libpng method of handling chunk CRC errors */
1600extern PNG_EXPORT(void,png_set_crc_action) PNGARG((png_structp png_ptr,
1601 int crit_action, int ancil_action));
1602
1603/* Values for png_set_crc_action() to say how to handle CRC errors in
1604 * ancillary and critical chunks, and whether to use the data contained
1605 * therein. Note that it is impossible to "discard" data in a critical
1606 * chunk. For versions prior to 0.90, the action was always error/quit,
1607 * whereas in version 0.90 and later, the action for CRC errors in ancillary
1608 * chunks is warn/discard. These values should NOT be changed.
1609 *
1610 * value action:critical action:ancillary
1611 */
1612#define PNG_CRC_DEFAULT 0 /* error/quit warn/discard data */
1613#define PNG_CRC_ERROR_QUIT 1 /* error/quit error/quit */
1614#define PNG_CRC_WARN_DISCARD 2 /* (INVALID) warn/discard data */
1615#define PNG_CRC_WARN_USE 3 /* warn/use data warn/use data */
1616#define PNG_CRC_QUIET_USE 4 /* quiet/use data quiet/use data */
1617#define PNG_CRC_NO_CHANGE 5 /* use current value use current value */
1618
1619/* These functions give the user control over the scan-line filtering in
1620 * libpng and the compression methods used by zlib. These functions are
1621 * mainly useful for testing, as the defaults should work with most users.
1622 * Those users who are tight on memory or want faster performance at the
1623 * expense of compression can modify them. See the compression library
1624 * header file (zlib.h) for an explination of the compression functions.
1625 */
1626
1627/* set the filtering method(s) used by libpng. Currently, the only valid
1628 * value for "method" is 0.
1629 */
1630extern PNG_EXPORT(void,png_set_filter) PNGARG((png_structp png_ptr, int method,
1631 int filters));
1632
1633/* Flags for png_set_filter() to say which filters to use. The flags
1634 * are chosen so that they don't conflict with real filter types
1635 * below, in case they are supplied instead of the #defined constants.
1636 * These values should NOT be changed.
1637 */
1638#define PNG_NO_FILTERS 0x00
1639#define PNG_FILTER_NONE 0x08
1640#define PNG_FILTER_SUB 0x10
1641#define PNG_FILTER_UP 0x20
1642#define PNG_FILTER_AVG 0x40
1643#define PNG_FILTER_PAETH 0x80
1644#define PNG_ALL_FILTERS (PNG_FILTER_NONE | PNG_FILTER_SUB | PNG_FILTER_UP | \
1645 PNG_FILTER_AVG | PNG_FILTER_PAETH)
1646
1647/* Filter values (not flags) - used in pngwrite.c, pngwutil.c for now.
1648 * These defines should NOT be changed.
1649 */
1650#define PNG_FILTER_VALUE_NONE 0
1651#define PNG_FILTER_VALUE_SUB 1
1652#define PNG_FILTER_VALUE_UP 2
1653#define PNG_FILTER_VALUE_AVG 3
1654#define PNG_FILTER_VALUE_PAETH 4
1655#define PNG_FILTER_VALUE_LAST 5
1656
1657#if defined(PNG_WRITE_WEIGHTED_FILTER_SUPPORTED) /* EXPERIMENTAL */
1658/* The "heuristic_method" is given by one of the PNG_FILTER_HEURISTIC_
1659 * defines, either the default (minimum-sum-of-absolute-differences), or
1660 * the experimental method (weighted-minimum-sum-of-absolute-differences).
1661 *
1662 * Weights are factors >= 1.0, indicating how important it is to keep the
1663 * filter type consistent between rows. Larger numbers mean the current
1664 * filter is that many times as likely to be the same as the "num_weights"
1665 * previous filters. This is cumulative for each previous row with a weight.
1666 * There needs to be "num_weights" values in "filter_weights", or it can be
1667 * NULL if the weights aren't being specified. Weights have no influence on
1668 * the selection of the first row filter. Well chosen weights can (in theory)
1669 * improve the compression for a given image.
1670 *
1671 * Costs are factors >= 1.0 indicating the relative decoding costs of a
1672 * filter type. Higher costs indicate more decoding expense, and are
1673 * therefore less likely to be selected over a filter with lower computational
1674 * costs. There needs to be a value in "filter_costs" for each valid filter
1675 * type (given by PNG_FILTER_VALUE_LAST), or it can be NULL if you aren't
1676 * setting the costs. Costs try to improve the speed of decompression without
1677 * unduly increasing the compressed image size.
1678 *
1679 * A negative weight or cost indicates the default value is to be used, and
1680 * values in the range [0.0, 1.0) indicate the value is to remain unchanged.
1681 * The default values for both weights and costs are currently 1.0, but may
1682 * change if good general weighting/cost heuristics can be found. If both
1683 * the weights and costs are set to 1.0, this degenerates the WEIGHTED method
1684 * to the UNWEIGHTED method, but with added encoding time/computation.
1685 */
4946a942 1686#ifdef PNG_FLOATING_POINT_SUPPORTED
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1687extern PNG_EXPORT(void,png_set_filter_heuristics) PNGARG((png_structp png_ptr,
1688 int heuristic_method, int num_weights, png_doublep filter_weights,
1689 png_doublep filter_costs));
4946a942 1690#endif
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1691#endif /* PNG_WRITE_WEIGHTED_FILTER_SUPPORTED */
1692
1693/* Heuristic used for row filter selection. These defines should NOT be
1694 * changed.
1695 */
1696#define PNG_FILTER_HEURISTIC_DEFAULT 0 /* Currently "UNWEIGHTED" */
1697#define PNG_FILTER_HEURISTIC_UNWEIGHTED 1 /* Used by libpng < 0.95 */
1698#define PNG_FILTER_HEURISTIC_WEIGHTED 2 /* Experimental feature */
1699#define PNG_FILTER_HEURISTIC_LAST 3 /* Not a valid value */
1700
1701/* Set the library compression level. Currently, valid values range from
1702 * 0 - 9, corresponding directly to the zlib compression levels 0 - 9
1703 * (0 - no compression, 9 - "maximal" compression). Note that tests have
1704 * shown that zlib compression levels 3-6 usually perform as well as level 9
1705 * for PNG images, and do considerably fewer caclulations. In the future,
1706 * these values may not correspond directly to the zlib compression levels.
1707 */
1708extern PNG_EXPORT(void,png_set_compression_level) PNGARG((png_structp png_ptr,
1709 int level));
1710
1711extern PNG_EXPORT(void,png_set_compression_mem_level)
1712 PNGARG((png_structp png_ptr, int mem_level));
1713
1714extern PNG_EXPORT(void,png_set_compression_strategy)
1715 PNGARG((png_structp png_ptr, int strategy));
1716
1717extern PNG_EXPORT(void,png_set_compression_window_bits)
1718 PNGARG((png_structp png_ptr, int window_bits));
1719
1720extern PNG_EXPORT(void,png_set_compression_method) PNGARG((png_structp png_ptr,
1721 int method));
1722
1723/* These next functions are called for input/output, memory, and error
1724 * handling. They are in the file pngrio.c, pngwio.c, and pngerror.c,
1725 * and call standard C I/O routines such as fread(), fwrite(), and
1726 * fprintf(). These functions can be made to use other I/O routines
1727 * at run time for those applications that need to handle I/O in a
1728 * different manner by calling png_set_???_fn(). See libpng.txt for
1729 * more information.
1730 */
1731
1732#if !defined(PNG_NO_STDIO)
1733/* Initialize the input/output for the PNG file to the default functions. */
4946a942 1734extern PNG_EXPORT(void,png_init_io) PNGARG((png_structp png_ptr, png_FILE_p fp));
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1735#endif
1736
1737/* Replace the (error and abort), and warning functions with user
1738 * supplied functions. If no messages are to be printed you must still
1739 * write and use replacement functions. The replacement error_fn should
1740 * still do a longjmp to the last setjmp location if you are using this
1741 * method of error handling. If error_fn or warning_fn is NULL, the
1742 * default function will be used.
1743 */
1744
1745extern PNG_EXPORT(void,png_set_error_fn) PNGARG((png_structp png_ptr,
1746 png_voidp error_ptr, png_error_ptr error_fn, png_error_ptr warning_fn));
1747
1748/* Return the user pointer associated with the error functions */
1749extern PNG_EXPORT(png_voidp,png_get_error_ptr) PNGARG((png_structp png_ptr));
1750
1751/* Replace the default data output functions with a user supplied one(s).
1752 * If buffered output is not used, then output_flush_fn can be set to NULL.
1753 * If PNG_WRITE_FLUSH_SUPPORTED is not defined at libpng compile time
1754 * output_flush_fn will be ignored (and thus can be NULL).
1755 */
1756extern PNG_EXPORT(void,png_set_write_fn) PNGARG((png_structp png_ptr,
1757 png_voidp io_ptr, png_rw_ptr write_data_fn, png_flush_ptr output_flush_fn));
1758
1759/* Replace the default data input function with a user supplied one. */
1760extern PNG_EXPORT(void,png_set_read_fn) PNGARG((png_structp png_ptr,
1761 png_voidp io_ptr, png_rw_ptr read_data_fn));
1762
1763/* Return the user pointer associated with the I/O functions */
1764extern PNG_EXPORT(png_voidp,png_get_io_ptr) PNGARG((png_structp png_ptr));
1765
1766extern PNG_EXPORT(void,png_set_read_status_fn) PNGARG((png_structp png_ptr,
1767 png_read_status_ptr read_row_fn));
1768
1769extern PNG_EXPORT(void,png_set_write_status_fn) PNGARG((png_structp png_ptr,
1770 png_write_status_ptr write_row_fn));
1771
1772#ifdef PNG_USER_MEM_SUPPORTED
1773/* Replace the default memory allocation functions with user supplied one(s). */
1774extern PNG_EXPORT(void,png_set_mem_fn) PNGARG((png_structp png_ptr,
1775 png_voidp mem_ptr, png_malloc_ptr malloc_fn, png_free_ptr free_fn));
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1776/* Return the user pointer associated with the memory functions */
1777extern PNG_EXPORT(png_voidp,png_get_mem_ptr) PNGARG((png_structp png_ptr));
4946a942 1778#endif
75b6e0a0 1779
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1780#if defined(PNG_READ_USER_TRANSFORM_SUPPORTED) || \
1781 defined(PNG_LEGACY_SUPPORTED)
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1782extern PNG_EXPORT(void,png_set_read_user_transform_fn) PNGARG((png_structp
1783 png_ptr, png_user_transform_ptr read_user_transform_fn));
1784#endif
1785
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1786#if defined(PNG_WRITE_USER_TRANSFORM_SUPPORTED) || \
1787 defined(PNG_LEGACY_SUPPORTED)
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1788extern PNG_EXPORT(void,png_set_write_user_transform_fn) PNGARG((png_structp
1789 png_ptr, png_user_transform_ptr write_user_transform_fn));
1790#endif
1791
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1792#if defined(PNG_READ_USER_TRANSFORM_SUPPORTED) || \
1793 defined(PNG_WRITE_USER_TRANSFORM_SUPPORTED) || \
1794 defined(PNG_LEGACY_SUPPORTED)
1795extern PNG_EXPORT(void,png_set_user_transform_info) PNGARG((png_structp
1796 png_ptr, png_voidp user_transform_ptr, int user_transform_depth,
1797 int user_transform_channels));
1798/* Return the user pointer associated with the user transform functions */
1799extern PNG_EXPORT(png_voidp,png_get_user_transform_ptr)
1800 PNGARG((png_structp png_ptr));
1801#endif
1802
1803#ifdef PNG_USER_CHUNKS_SUPPORTED
1804extern PNG_EXPORT(void,png_set_read_user_chunk_fn) PNGARG((png_structp png_ptr,
1805 png_voidp user_chunk_ptr, png_user_chunk_ptr read_user_chunk_fn));
1806extern PNG_EXPORT(png_voidp,png_get_user_chunk_ptr) PNGARG((png_structp
1807 png_ptr));
1808#endif
1809
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1810#ifdef PNG_PROGRESSIVE_READ_SUPPORTED
1811/* Sets the function callbacks for the push reader, and a pointer to a
1812 * user-defined structure available to the callback functions.
1813 */
1814extern PNG_EXPORT(void,png_set_progressive_read_fn) PNGARG((png_structp png_ptr,
1815 png_voidp progressive_ptr,
1816 png_progressive_info_ptr info_fn, png_progressive_row_ptr row_fn,
1817 png_progressive_end_ptr end_fn));
1818
1819/* returns the user pointer associated with the push read functions */
1820extern PNG_EXPORT(png_voidp,png_get_progressive_ptr)
1821 PNGARG((png_structp png_ptr));
1822
1823/* function to be called when data becomes available */
1824extern PNG_EXPORT(void,png_process_data) PNGARG((png_structp png_ptr,
1825 png_infop info_ptr, png_bytep buffer, png_size_t buffer_size));
1826
1827/* function that combines rows. Not very much different than the
1828 * png_combine_row() call. Is this even used?????
1829 */
1830extern PNG_EXPORT(void,png_progressive_combine_row) PNGARG((png_structp png_ptr,
1831 png_bytep old_row, png_bytep new_row));
1832#endif /* PNG_PROGRESSIVE_READ_SUPPORTED */
1833
1834extern PNG_EXPORT(png_voidp,png_malloc) PNGARG((png_structp png_ptr,
1835 png_uint_32 size));
1836
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1837#if defined(PNG_1_0_X)
1838# define png_malloc_warn png_malloc
1839#else
1840/* Added at libpng version 1.2.4 */
1841extern PNG_EXPORT(png_voidp,png_malloc_warn) PNGARG((png_structp png_ptr,
1842 png_uint_32 size));
1843#endif
1844
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1845/* frees a pointer allocated by png_malloc() */
1846extern PNG_EXPORT(void,png_free) PNGARG((png_structp png_ptr, png_voidp ptr));
1847
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1848#if defined(PNG_1_0_X)
1849/* Function to allocate memory for zlib. */
1850extern PNG_EXPORT(voidpf,png_zalloc) PNGARG((voidpf png_ptr, uInt items,
1851 uInt size));
1852
1853/* Function to free memory for zlib */
1854extern PNG_EXPORT(void,png_zfree) PNGARG((voidpf png_ptr, voidpf ptr));
1855#endif
1856
1857/* Free data that was allocated internally */
1858extern PNG_EXPORT(void,png_free_data) PNGARG((png_structp png_ptr,
1859 png_infop info_ptr, png_uint_32 free_me, int num));
1860#ifdef PNG_FREE_ME_SUPPORTED
1861/* Reassign responsibility for freeing existing data, whether allocated
1862 * by libpng or by the application */
1863extern PNG_EXPORT(void,png_data_freer) PNGARG((png_structp png_ptr,
1864 png_infop info_ptr, int freer, png_uint_32 mask));
1865#endif
1866/* assignments for png_data_freer */
1867#define PNG_DESTROY_WILL_FREE_DATA 1
1868#define PNG_SET_WILL_FREE_DATA 1
1869#define PNG_USER_WILL_FREE_DATA 2
1870/* Flags for png_ptr->free_me and info_ptr->free_me */
1871#define PNG_FREE_HIST 0x0008
1872#define PNG_FREE_ICCP 0x0010
1873#define PNG_FREE_SPLT 0x0020
1874#define PNG_FREE_ROWS 0x0040
1875#define PNG_FREE_PCAL 0x0080
1876#define PNG_FREE_SCAL 0x0100
1877#define PNG_FREE_UNKN 0x0200
1878#define PNG_FREE_LIST 0x0400
1879#define PNG_FREE_PLTE 0x1000
1880#define PNG_FREE_TRNS 0x2000
1881#define PNG_FREE_TEXT 0x4000
1882#define PNG_FREE_ALL 0x7fff
1883#define PNG_FREE_MUL 0x4220 /* PNG_FREE_SPLT|PNG_FREE_TEXT|PNG_FREE_UNKN */
1884
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1885#ifdef PNG_USER_MEM_SUPPORTED
1886extern PNG_EXPORT(png_voidp,png_malloc_default) PNGARG((png_structp png_ptr,
1887 png_uint_32 size));
1888extern PNG_EXPORT(void,png_free_default) PNGARG((png_structp png_ptr,
1889 png_voidp ptr));
4946a942 1890#endif
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1891
1892extern PNG_EXPORT(png_voidp,png_memcpy_check) PNGARG((png_structp png_ptr,
1893 png_voidp s1, png_voidp s2, png_uint_32 size));
1894
1895extern PNG_EXPORT(png_voidp,png_memset_check) PNGARG((png_structp png_ptr,
1896 png_voidp s1, int value, png_uint_32 size));
1897
1898#if defined(USE_FAR_KEYWORD) /* memory model conversion function */
1899extern void *png_far_to_near PNGARG((png_structp png_ptr,png_voidp ptr,
1900 int check));
1901#endif /* USE_FAR_KEYWORD */
1902
1903/* Fatal error in PNG image of libpng - can't continue */
1904extern PNG_EXPORT(void,png_error) PNGARG((png_structp png_ptr,
4946a942 1905 png_const_charp error_message));
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1906
1907/* The same, but the chunk name is prepended to the error string. */
1908extern PNG_EXPORT(void,png_chunk_error) PNGARG((png_structp png_ptr,
4946a942 1909 png_const_charp error_message));
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1910
1911/* Non-fatal error in libpng. Can continue, but may have a problem. */
1912extern PNG_EXPORT(void,png_warning) PNGARG((png_structp png_ptr,
4946a942 1913 png_const_charp warning_message));
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1914
1915/* Non-fatal error in libpng, chunk name is prepended to message. */
1916extern PNG_EXPORT(void,png_chunk_warning) PNGARG((png_structp png_ptr,
4946a942 1917 png_const_charp warning_message));
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1918
1919/* The png_set_<chunk> functions are for storing values in the png_info_struct.
1920 * Similarly, the png_get_<chunk> calls are used to read values from the
1921 * png_info_struct, either storing the parameters in the passed variables, or
1922 * setting pointers into the png_info_struct where the data is stored. The
1923 * png_get_<chunk> functions return a non-zero value if the data was available
1924 * in info_ptr, or return zero and do not change any of the parameters if the
1925 * data was not available.
1926 *
1927 * These functions should be used instead of directly accessing png_info
1928 * to avoid problems with future changes in the size and internal layout of
1929 * png_info_struct.
1930 */
1931/* Returns "flag" if chunk data is valid in info_ptr. */
1932extern PNG_EXPORT(png_uint_32,png_get_valid) PNGARG((png_structp png_ptr,
1933png_infop info_ptr, png_uint_32 flag));
1934
1935/* Returns number of bytes needed to hold a transformed row. */
1936extern PNG_EXPORT(png_uint_32,png_get_rowbytes) PNGARG((png_structp png_ptr,
1937png_infop info_ptr));
1938
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1939#if defined(PNG_INFO_IMAGE_SUPPORTED)
1940/* Returns row_pointers, which is an array of pointers to scanlines that was
1941returned from png_read_png(). */
1942extern PNG_EXPORT(png_bytepp,png_get_rows) PNGARG((png_structp png_ptr,
1943png_infop info_ptr));
1944/* Set row_pointers, which is an array of pointers to scanlines for use
1945by png_write_png(). */
1946extern PNG_EXPORT(void,png_set_rows) PNGARG((png_structp png_ptr,
1947 png_infop info_ptr, png_bytepp row_pointers));
1948#endif
1949
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1950/* Returns number of color channels in image. */
1951extern PNG_EXPORT(png_byte,png_get_channels) PNGARG((png_structp png_ptr,
1952png_infop info_ptr));
1953
1954#ifdef PNG_EASY_ACCESS_SUPPORTED
1955/* Returns image width in pixels. */
1956extern PNG_EXPORT(png_uint_32, png_get_image_width) PNGARG((png_structp
1957png_ptr, png_infop info_ptr));
1958
1959/* Returns image height in pixels. */
1960extern PNG_EXPORT(png_uint_32, png_get_image_height) PNGARG((png_structp
1961png_ptr, png_infop info_ptr));
1962
1963/* Returns image bit_depth. */
1964extern PNG_EXPORT(png_byte, png_get_bit_depth) PNGARG((png_structp
1965png_ptr, png_infop info_ptr));
1966
1967/* Returns image color_type. */
1968extern PNG_EXPORT(png_byte, png_get_color_type) PNGARG((png_structp
1969png_ptr, png_infop info_ptr));
1970
1971/* Returns image filter_type. */
1972extern PNG_EXPORT(png_byte, png_get_filter_type) PNGARG((png_structp
1973png_ptr, png_infop info_ptr));
1974
1975/* Returns image interlace_type. */
1976extern PNG_EXPORT(png_byte, png_get_interlace_type) PNGARG((png_structp
1977png_ptr, png_infop info_ptr));
1978
1979/* Returns image compression_type. */
1980extern PNG_EXPORT(png_byte, png_get_compression_type) PNGARG((png_structp
1981png_ptr, png_infop info_ptr));
1982
1983/* Returns image resolution in pixels per meter, from pHYs chunk data. */
1984extern PNG_EXPORT(png_uint_32, png_get_pixels_per_meter) PNGARG((png_structp
1985png_ptr, png_infop info_ptr));
1986extern PNG_EXPORT(png_uint_32, png_get_x_pixels_per_meter) PNGARG((png_structp
1987png_ptr, png_infop info_ptr));
1988extern PNG_EXPORT(png_uint_32, png_get_y_pixels_per_meter) PNGARG((png_structp
1989png_ptr, png_infop info_ptr));
1990
1991/* Returns pixel aspect ratio, computed from pHYs chunk data. */
4946a942 1992#ifdef PNG_FLOATING_POINT_SUPPORTED
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1993extern PNG_EXPORT(float, png_get_pixel_aspect_ratio) PNGARG((png_structp
1994png_ptr, png_infop info_ptr));
4946a942 1995#endif
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1996
1997/* Returns image x, y offset in pixels or microns, from oFFs chunk data. */
4946a942 1998extern PNG_EXPORT(png_int_32, png_get_x_offset_pixels) PNGARG((png_structp
75b6e0a0 1999png_ptr, png_infop info_ptr));
4946a942 2000extern PNG_EXPORT(png_int_32, png_get_y_offset_pixels) PNGARG((png_structp
75b6e0a0 2001png_ptr, png_infop info_ptr));
4946a942 2002extern PNG_EXPORT(png_int_32, png_get_x_offset_microns) PNGARG((png_structp
75b6e0a0 2003png_ptr, png_infop info_ptr));
4946a942 2004extern PNG_EXPORT(png_int_32, png_get_y_offset_microns) PNGARG((png_structp
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2005png_ptr, png_infop info_ptr));
2006
2007#endif /* PNG_EASY_ACCESS_SUPPORTED */
2008
2009/* Returns pointer to signature string read from PNG header */
2010extern PNG_EXPORT(png_bytep,png_get_signature) PNGARG((png_structp png_ptr,
2011png_infop info_ptr));
2012
4946a942 2013#if defined(PNG_bKGD_SUPPORTED)
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2014extern PNG_EXPORT(png_uint_32,png_get_bKGD) PNGARG((png_structp png_ptr,
2015 png_infop info_ptr, png_color_16p *background));
4946a942 2016#endif
75b6e0a0 2017
4946a942 2018#if defined(PNG_bKGD_SUPPORTED)
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2019extern PNG_EXPORT(void,png_set_bKGD) PNGARG((png_structp png_ptr,
2020 png_infop info_ptr, png_color_16p background));
4946a942 2021#endif
75b6e0a0 2022
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2023#if defined(PNG_cHRM_SUPPORTED)
2024#ifdef PNG_FLOATING_POINT_SUPPORTED
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2025extern PNG_EXPORT(png_uint_32,png_get_cHRM) PNGARG((png_structp png_ptr,
2026 png_infop info_ptr, double *white_x, double *white_y, double *red_x,
2027 double *red_y, double *green_x, double *green_y, double *blue_x,
2028 double *blue_y));
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2029#endif
2030#ifdef PNG_FIXED_POINT_SUPPORTED
2031extern PNG_EXPORT(png_uint_32,png_get_cHRM_fixed) PNGARG((png_structp png_ptr,
2032 png_infop info_ptr, png_fixed_point *int_white_x, png_fixed_point
2033 *int_white_y, png_fixed_point *int_red_x, png_fixed_point *int_red_y,
2034 png_fixed_point *int_green_x, png_fixed_point *int_green_y, png_fixed_point
2035 *int_blue_x, png_fixed_point *int_blue_y));
2036#endif
2037#endif
75b6e0a0 2038
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2039#if defined(PNG_cHRM_SUPPORTED)
2040#ifdef PNG_FLOATING_POINT_SUPPORTED
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2041extern PNG_EXPORT(void,png_set_cHRM) PNGARG((png_structp png_ptr,
2042 png_infop info_ptr, double white_x, double white_y, double red_x,
2043 double red_y, double green_x, double green_y, double blue_x, double blue_y));
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2044#endif
2045#ifdef PNG_FIXED_POINT_SUPPORTED
2046extern PNG_EXPORT(void,png_set_cHRM_fixed) PNGARG((png_structp png_ptr,
2047 png_infop info_ptr, png_fixed_point int_white_x, png_fixed_point int_white_y,
2048 png_fixed_point int_red_x, png_fixed_point int_red_y, png_fixed_point
2049 int_green_x, png_fixed_point int_green_y, png_fixed_point int_blue_x,
2050 png_fixed_point int_blue_y));
2051#endif
2052#endif
75b6e0a0 2053
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2054#if defined(PNG_gAMA_SUPPORTED)
2055#ifdef PNG_FLOATING_POINT_SUPPORTED
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2056extern PNG_EXPORT(png_uint_32,png_get_gAMA) PNGARG((png_structp png_ptr,
2057 png_infop info_ptr, double *file_gamma));
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2058#endif
2059extern PNG_EXPORT(png_uint_32,png_get_gAMA_fixed) PNGARG((png_structp png_ptr,
2060 png_infop info_ptr, png_fixed_point *int_file_gamma));
2061#endif
75b6e0a0 2062
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2063#if defined(PNG_gAMA_SUPPORTED)
2064#ifdef PNG_FLOATING_POINT_SUPPORTED
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2065extern PNG_EXPORT(void,png_set_gAMA) PNGARG((png_structp png_ptr,
2066 png_infop info_ptr, double file_gamma));
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2067#endif
2068extern PNG_EXPORT(void,png_set_gAMA_fixed) PNGARG((png_structp png_ptr,
2069 png_infop info_ptr, png_fixed_point int_file_gamma));
2070#endif
75b6e0a0 2071
4946a942 2072#if defined(PNG_hIST_SUPPORTED)
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2073extern PNG_EXPORT(png_uint_32,png_get_hIST) PNGARG((png_structp png_ptr,
2074 png_infop info_ptr, png_uint_16p *hist));
4946a942 2075#endif
75b6e0a0 2076
4946a942 2077#if defined(PNG_hIST_SUPPORTED)
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2078extern PNG_EXPORT(void,png_set_hIST) PNGARG((png_structp png_ptr,
2079 png_infop info_ptr, png_uint_16p hist));
4946a942 2080#endif
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2081
2082extern PNG_EXPORT(png_uint_32,png_get_IHDR) PNGARG((png_structp png_ptr,
2083 png_infop info_ptr, png_uint_32 *width, png_uint_32 *height,
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2084 int *bit_depth, int *color_type, int *interlace_method,
2085 int *compression_method, int *filter_method));
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2086
2087extern PNG_EXPORT(void,png_set_IHDR) PNGARG((png_structp png_ptr,
2088 png_infop info_ptr, png_uint_32 width, png_uint_32 height, int bit_depth,
4946a942
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2089 int color_type, int interlace_method, int compression_method,
2090 int filter_method));
75b6e0a0 2091
4946a942 2092#if defined(PNG_oFFs_SUPPORTED)
75b6e0a0 2093extern PNG_EXPORT(png_uint_32,png_get_oFFs) PNGARG((png_structp png_ptr,
4946a942 2094 png_infop info_ptr, png_int_32 *offset_x, png_int_32 *offset_y,
75b6e0a0 2095 int *unit_type));
4946a942 2096#endif
75b6e0a0 2097
4946a942 2098#if defined(PNG_oFFs_SUPPORTED)
75b6e0a0 2099extern PNG_EXPORT(void,png_set_oFFs) PNGARG((png_structp png_ptr,
4946a942 2100 png_infop info_ptr, png_int_32 offset_x, png_int_32 offset_y,
75b6e0a0 2101 int unit_type));
4946a942 2102#endif
75b6e0a0 2103
4946a942 2104#if defined(PNG_pCAL_SUPPORTED)
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2105extern PNG_EXPORT(png_uint_32,png_get_pCAL) PNGARG((png_structp png_ptr,
2106 png_infop info_ptr, png_charp *purpose, png_int_32 *X0, png_int_32 *X1,
2107 int *type, int *nparams, png_charp *units, png_charpp *params));
4946a942 2108#endif
75b6e0a0 2109
4946a942 2110#if defined(PNG_pCAL_SUPPORTED)
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2111extern PNG_EXPORT(void,png_set_pCAL) PNGARG((png_structp png_ptr,
2112 png_infop info_ptr, png_charp purpose, png_int_32 X0, png_int_32 X1,
2113 int type, int nparams, png_charp units, png_charpp params));
4946a942 2114#endif
75b6e0a0 2115
4946a942 2116#if defined(PNG_pHYs_SUPPORTED)
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2117extern PNG_EXPORT(png_uint_32,png_get_pHYs) PNGARG((png_structp png_ptr,
2118 png_infop info_ptr, png_uint_32 *res_x, png_uint_32 *res_y, int *unit_type));
4946a942 2119#endif
75b6e0a0 2120
4946a942 2121#if defined(PNG_pHYs_SUPPORTED)
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2122extern PNG_EXPORT(void,png_set_pHYs) PNGARG((png_structp png_ptr,
2123 png_infop info_ptr, png_uint_32 res_x, png_uint_32 res_y, int unit_type));
4946a942 2124#endif
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2125
2126extern PNG_EXPORT(png_uint_32,png_get_PLTE) PNGARG((png_structp png_ptr,
2127 png_infop info_ptr, png_colorp *palette, int *num_palette));
2128
2129extern PNG_EXPORT(void,png_set_PLTE) PNGARG((png_structp png_ptr,
2130 png_infop info_ptr, png_colorp palette, int num_palette));
2131
4946a942 2132#if defined(PNG_sBIT_SUPPORTED)
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2133extern PNG_EXPORT(png_uint_32,png_get_sBIT) PNGARG((png_structp png_ptr,
2134 png_infop info_ptr, png_color_8p *sig_bit));
4946a942 2135#endif
75b6e0a0 2136
4946a942 2137#if defined(PNG_sBIT_SUPPORTED)
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2138extern PNG_EXPORT(void,png_set_sBIT) PNGARG((png_structp png_ptr,
2139 png_infop info_ptr, png_color_8p sig_bit));
4946a942 2140#endif
75b6e0a0 2141
4946a942 2142#if defined(PNG_sRGB_SUPPORTED)
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2143extern PNG_EXPORT(png_uint_32,png_get_sRGB) PNGARG((png_structp png_ptr,
2144 png_infop info_ptr, int *intent));
4946a942 2145#endif
75b6e0a0 2146
4946a942 2147#if defined(PNG_sRGB_SUPPORTED)
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2148extern PNG_EXPORT(void,png_set_sRGB) PNGARG((png_structp png_ptr,
2149 png_infop info_ptr, int intent));
2150extern PNG_EXPORT(void,png_set_sRGB_gAMA_and_cHRM) PNGARG((png_structp png_ptr,
2151 png_infop info_ptr, int intent));
4946a942 2152#endif
75b6e0a0 2153
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2154#if defined(PNG_iCCP_SUPPORTED)
2155extern PNG_EXPORT(png_uint_32,png_get_iCCP) PNGARG((png_structp png_ptr,
2156 png_infop info_ptr, png_charpp name, int *compression_type,
2157 png_charpp profile, png_uint_32 *proflen));
2158 /* Note to maintainer: profile should be png_bytepp */
2159#endif
2160
2161#if defined(PNG_iCCP_SUPPORTED)
2162extern PNG_EXPORT(void,png_set_iCCP) PNGARG((png_structp png_ptr,
2163 png_infop info_ptr, png_charp name, int compression_type,
2164 png_charp profile, png_uint_32 proflen));
2165 /* Note to maintainer: profile should be png_bytep */
2166#endif
2167
2168#if defined(PNG_sPLT_SUPPORTED)
2169extern PNG_EXPORT(png_uint_32,png_get_sPLT) PNGARG((png_structp png_ptr,
2170 png_infop info_ptr, png_sPLT_tpp entries));
2171#endif
2172
2173#if defined(PNG_sPLT_SUPPORTED)
2174extern PNG_EXPORT(void,png_set_sPLT) PNGARG((png_structp png_ptr,
2175 png_infop info_ptr, png_sPLT_tp entries, int nentries));
2176#endif
2177
2178#if defined(PNG_TEXT_SUPPORTED)
2179/* png_get_text also returns the number of text chunks in *num_text */
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2180extern PNG_EXPORT(png_uint_32,png_get_text) PNGARG((png_structp png_ptr,
2181 png_infop info_ptr, png_textp *text_ptr, int *num_text));
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2182#endif
2183
2184/*
2185 * Note while png_set_text() will accept a structure whose text,
2186 * language, and translated keywords are NULL pointers, the structure
2187 * returned by png_get_text will always contain regular
2188 * zero-terminated C strings. They might be empty strings but
2189 * they will never be NULL pointers.
2190 */
75b6e0a0 2191
4946a942 2192#if defined(PNG_TEXT_SUPPORTED)
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2193extern PNG_EXPORT(void,png_set_text) PNGARG((png_structp png_ptr,
2194 png_infop info_ptr, png_textp text_ptr, int num_text));
4946a942 2195#endif
75b6e0a0 2196
4946a942 2197#if defined(PNG_tIME_SUPPORTED)
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2198extern PNG_EXPORT(png_uint_32,png_get_tIME) PNGARG((png_structp png_ptr,
2199 png_infop info_ptr, png_timep *mod_time));
4946a942 2200#endif
75b6e0a0 2201
4946a942 2202#if defined(PNG_tIME_SUPPORTED)
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2203extern PNG_EXPORT(void,png_set_tIME) PNGARG((png_structp png_ptr,
2204 png_infop info_ptr, png_timep mod_time));
4946a942 2205#endif
75b6e0a0 2206
4946a942 2207#if defined(PNG_tRNS_SUPPORTED)
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2208extern PNG_EXPORT(png_uint_32,png_get_tRNS) PNGARG((png_structp png_ptr,
2209 png_infop info_ptr, png_bytep *trans, int *num_trans,
2210 png_color_16p *trans_values));
4946a942 2211#endif
75b6e0a0 2212
4946a942 2213#if defined(PNG_tRNS_SUPPORTED)
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2214extern PNG_EXPORT(void,png_set_tRNS) PNGARG((png_structp png_ptr,
2215 png_infop info_ptr, png_bytep trans, int num_trans,
2216 png_color_16p trans_values));
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2217#endif
2218
2219#if defined(PNG_tRNS_SUPPORTED)
2220#endif
2221
2222#if defined(PNG_sCAL_SUPPORTED)
2223#ifdef PNG_FLOATING_POINT_SUPPORTED
2224extern PNG_EXPORT(png_uint_32,png_get_sCAL) PNGARG((png_structp png_ptr,
2225 png_infop info_ptr, int *unit, double *width, double *height));
2226#else
2227#ifdef PNG_FIXED_POINT_SUPPORTED
2228extern PNG_EXPORT(png_uint_32,png_get_sCAL_s) PNGARG((png_structp png_ptr,
2229 png_infop info_ptr, int *unit, png_charpp swidth, png_charpp sheight));
2230#endif
2231#endif
2232#endif /* PNG_sCAL_SUPPORTED */
2233
2234#if defined(PNG_sCAL_SUPPORTED)
2235#ifdef PNG_FLOATING_POINT_SUPPORTED
2236extern PNG_EXPORT(void,png_set_sCAL) PNGARG((png_structp png_ptr,
2237 png_infop info_ptr, int unit, double width, double height));
2238#endif
2239#ifdef PNG_FIXED_POINT_SUPPORTED
2240extern PNG_EXPORT(void,png_set_sCAL_s) PNGARG((png_structp png_ptr,
2241 png_infop info_ptr, int unit, png_charp swidth, png_charp sheight));
2242#endif
2243#endif /* PNG_sCAL_SUPPORTED || PNG_WRITE_sCAL_SUPPORTED */
2244
2245#if defined(PNG_UNKNOWN_CHUNKS_SUPPORTED)
2246/* provide a list of chunks and how they are to be handled, if the built-in
2247 handling or default unknown chunk handling is not desired. Any chunks not
2248 listed will be handled in the default manner. The IHDR and IEND chunks
2249 must not be listed.
2250 keep = 0: follow default behavour
2251 = 1: do not keep
2252 = 2: keep only if safe-to-copy
2253 = 3: keep even if unsafe-to-copy
2254*/
2255extern PNG_EXPORT(void, png_set_keep_unknown_chunks) PNGARG((png_structp
2256 png_ptr, int keep, png_bytep chunk_list, int num_chunks));
2257extern PNG_EXPORT(void, png_set_unknown_chunks) PNGARG((png_structp png_ptr,
2258 png_infop info_ptr, png_unknown_chunkp unknowns, int num_unknowns));
2259extern PNG_EXPORT(void, png_set_unknown_chunk_location)
2260 PNGARG((png_structp png_ptr, png_infop info_ptr, int chunk, int location));
2261extern PNG_EXPORT(png_uint_32,png_get_unknown_chunks) PNGARG((png_structp
2262 png_ptr, png_infop info_ptr, png_unknown_chunkpp entries));
2263#endif
2264#ifdef PNG_HANDLE_AS_UNKNOWN_SUPPORTED
2265PNG_EXPORT(int,png_handle_as_unknown) PNGARG((png_structp png_ptr, png_bytep
2266 chunk_name));
2267#endif
2268
2269/* Png_free_data() will turn off the "valid" flag for anything it frees.
2270 If you need to turn it off for a chunk that your application has freed,
2271 you can use png_set_invalid(png_ptr, info_ptr, PNG_INFO_CHNK); */
2272extern PNG_EXPORT(void, png_set_invalid) PNGARG((png_structp png_ptr,
2273 png_infop info_ptr, int mask));
2274
2275#if defined(PNG_INFO_IMAGE_SUPPORTED)
2276/* The "params" pointer is currently not used and is for future expansion. */
2277extern PNG_EXPORT(void, png_read_png) PNGARG((png_structp png_ptr,
2278 png_infop info_ptr,
2279 int transforms,
2280 png_voidp params));
2281extern PNG_EXPORT(void, png_write_png) PNGARG((png_structp png_ptr,
2282 png_infop info_ptr,
2283 int transforms,
2284 png_voidp params));
2285#endif
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GD
2286
2287/* Define PNG_DEBUG at compile time for debugging information. Higher
2288 * numbers for PNG_DEBUG mean more debugging information. This has
2289 * only been added since version 0.95 so it is not implemented throughout
2290 * libpng yet, but more support will be added as needed.
2291 */
2292#ifdef PNG_DEBUG
2293#if (PNG_DEBUG > 0)
4946a942
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2294#if !defined(PNG_DEBUG_FILE) && defined(_MSC_VER)
2295#include <crtdbg.h>
2296#if (PNG_DEBUG > 1)
2297#define png_debug(l,m) _RPT0(_CRT_WARN,m)
2298#define png_debug1(l,m,p1) _RPT1(_CRT_WARN,m,p1)
2299#define png_debug2(l,m,p1,p2) _RPT2(_CRT_WARN,m,p1,p2)
2300#endif
2301#else /* PNG_DEBUG_FILE || !_MSC_VER */
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2302#ifndef PNG_DEBUG_FILE
2303#define PNG_DEBUG_FILE stderr
2304#endif /* PNG_DEBUG_FILE */
4946a942
GD
2305#if (PNG_DEBUG > 1)
2306#define png_debug(l,m) \
2307{ \
2308 int num_tabs=l; \
2309 fprintf(PNG_DEBUG_FILE,"%s"m,(num_tabs==1 ? "\t" : \
2310 (num_tabs==2 ? "\t\t":(num_tabs>2 ? "\t\t\t":"")))); \
2311}
2312#define png_debug1(l,m,p1) \
2313{ \
2314 int num_tabs=l; \
2315 fprintf(PNG_DEBUG_FILE,"%s"m,(num_tabs==1 ? "\t" : \
2316 (num_tabs==2 ? "\t\t":(num_tabs>2 ? "\t\t\t":""))),p1); \
2317}
2318#define png_debug2(l,m,p1,p2) \
2319{ \
2320 int num_tabs=l; \
2321 fprintf(PNG_DEBUG_FILE,"%s"m,(num_tabs==1 ? "\t" : \
2322 (num_tabs==2 ? "\t\t":(num_tabs>2 ? "\t\t\t":""))),p1,p2); \
2323}
2324#endif /* (PNG_DEBUG > 1) */
2325#endif /* _MSC_VER */
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GD
2326#endif /* (PNG_DEBUG > 0) */
2327#endif /* PNG_DEBUG */
2328#ifndef png_debug
2329#define png_debug(l, m)
2330#endif
2331#ifndef png_debug1
2332#define png_debug1(l, m, p1)
2333#endif
2334#ifndef png_debug2
2335#define png_debug2(l, m, p1, p2)
2336#endif
2337
4946a942
GD
2338extern PNG_EXPORT(png_bytep,png_sig_bytes) PNGARG((void));
2339
75b6e0a0 2340extern PNG_EXPORT(png_charp,png_get_copyright) PNGARG((png_structp png_ptr));
4946a942 2341extern PNG_EXPORT(png_charp,png_get_header_ver) PNGARG((png_structp png_ptr));
75b6e0a0 2342extern PNG_EXPORT(png_charp,png_get_header_version) PNGARG((png_structp png_ptr));
4946a942
GD
2343extern PNG_EXPORT(png_charp,png_get_libpng_ver) PNGARG((png_structp png_ptr));
2344
2345#ifdef PNG_MNG_FEATURES_SUPPORTED
2346extern PNG_EXPORT(png_uint_32,png_permit_mng_features) PNGARG((png_structp
2347 png_ptr, png_uint_32 mng_features_permitted));
2348#endif
2349
2350/* Added to version 1.2.0 */
2351#if defined(PNG_ASSEMBLER_CODE_SUPPORTED)
2352#define PNG_ASM_FLAG_MMX_SUPPORT_COMPILED 0x01 /* not user-settable */
2353#define PNG_ASM_FLAG_MMX_SUPPORT_IN_CPU 0x02 /* not user-settable */
2354#define PNG_ASM_FLAG_MMX_READ_COMBINE_ROW 0x04
2355#define PNG_ASM_FLAG_MMX_READ_INTERLACE 0x08
2356#define PNG_ASM_FLAG_MMX_READ_FILTER_SUB 0x10
2357#define PNG_ASM_FLAG_MMX_READ_FILTER_UP 0x20
2358#define PNG_ASM_FLAG_MMX_READ_FILTER_AVG 0x40
2359#define PNG_ASM_FLAG_MMX_READ_FILTER_PAETH 0x80
2360#define PNG_ASM_FLAGS_INITIALIZED 0x80000000 /* not user-settable */
2361
2362#define PNG_MMX_READ_FLAGS ( PNG_ASM_FLAG_MMX_READ_COMBINE_ROW \
2363 | PNG_ASM_FLAG_MMX_READ_INTERLACE \
2364 | PNG_ASM_FLAG_MMX_READ_FILTER_SUB \
2365 | PNG_ASM_FLAG_MMX_READ_FILTER_UP \
2366 | PNG_ASM_FLAG_MMX_READ_FILTER_AVG \
2367 | PNG_ASM_FLAG_MMX_READ_FILTER_PAETH )
2368#define PNG_MMX_WRITE_FLAGS ( 0 )
2369
2370#define PNG_MMX_FLAGS ( PNG_ASM_FLAG_MMX_SUPPORT_COMPILED \
2371 | PNG_ASM_FLAG_MMX_SUPPORT_IN_CPU \
2372 | PNG_MMX_READ_FLAGS \
2373 | PNG_MMX_WRITE_FLAGS )
2374
2375#define PNG_SELECT_READ 1
2376#define PNG_SELECT_WRITE 2
2377
2378
2379#if !defined(PNG_1_0_X)
2380/* pngget.c */
2381extern PNG_EXPORT(png_uint_32,png_get_mmx_flagmask)
2382 PNGARG((int flag_select, int *compilerID));
2383
2384/* pngget.c */
2385extern PNG_EXPORT(png_uint_32,png_get_asm_flagmask)
2386 PNGARG((int flag_select));
2387
2388/* pngget.c */
2389extern PNG_EXPORT(png_uint_32,png_get_asm_flags)
2390 PNGARG((png_structp png_ptr));
75b6e0a0 2391
4946a942
GD
2392/* pngget.c */
2393extern PNG_EXPORT(png_byte,png_get_mmx_bitdepth_threshold)
2394 PNGARG((png_structp png_ptr));
2395
2396/* pngget.c */
2397extern PNG_EXPORT(png_uint_32,png_get_mmx_rowbytes_threshold)
2398 PNGARG((png_structp png_ptr));
2399
2400/* pngset.c */
2401extern PNG_EXPORT(void,png_set_asm_flags)
2402 PNGARG((png_structp png_ptr, png_uint_32 asm_flags));
2403
2404/* pngset.c */
2405extern PNG_EXPORT(void,png_set_mmx_thresholds)
2406 PNGARG((png_structp png_ptr, png_byte mmx_bitdepth_threshold,
2407 png_uint_32 mmx_rowbytes_threshold));
2408
2409#endif /* PNG_1_0_X */
2410#endif /* PNG_ASSEMBLER_CODE_SUPPORTED */
2411
2412#if !defined(PNG_1_0_X)
2413/* png.c, pnggccrd.c, or pngvcrd.c */
2414extern PNG_EXPORT(int,png_mmx_support) PNGARG((void));
2415
2416/* Strip the prepended error numbers ("#nnn ") from error and warning
2417 * messages before passing them to the error or warning handler. */
2418#ifdef PNG_ERROR_NUMBERS_SUPPORTED
2419extern PNG_EXPORT(void,png_set_strip_error_numbers) PNGARG((png_structp
2420 png_ptr, png_uint_32 strip_mode));
75b6e0a0 2421#endif
4946a942
GD
2422#endif /* PNG_1_0_X */
2423
2424/* Maintainer: Put new public prototypes here ^, in libpng.3, and project defs */
2425
2426#define PNG_HEADER_VERSION_STRING \
2b5f62a0 2427 " libpng version 1.2.5rc3 - September 18, 2002 (header)\n"
75b6e0a0
GD
2428
2429#ifdef PNG_READ_COMPOSITE_NODIV_SUPPORTED
2430/* With these routines we avoid an integer divide, which will be slower on
2431 * most machines. However, it does take more operations than the corresponding
2432 * divide method, so it may be slower on a few RISC systems. There are two
2433 * shifts (by 8 or 16 bits) and an addition, versus a single integer divide.
2434 *
2435 * Note that the rounding factors are NOT supposed to be the same! 128 and
2436 * 32768 are correct for the NODIV code; 127 and 32767 are correct for the
2437 * standard method.
2438 *
2439 * [Optimized code by Greg Roelofs and Mark Adler...blame us for bugs. :-) ]
2440 */
2441
2442 /* fg and bg should be in `gamma 1.0' space; alpha is the opacity */
2443
2444# define png_composite(composite, fg, alpha, bg) \
4946a942
GD
2445 { png_uint_16 temp = (png_uint_16)((png_uint_16)(fg) * (png_uint_16)(alpha) \
2446 + (png_uint_16)(bg)*(png_uint_16)(255 - \
75b6e0a0
GD
2447 (png_uint_16)(alpha)) + (png_uint_16)128); \
2448 (composite) = (png_byte)((temp + (temp >> 8)) >> 8); }
2449
2450# define png_composite_16(composite, fg, alpha, bg) \
4946a942
GD
2451 { png_uint_32 temp = (png_uint_32)((png_uint_32)(fg) * (png_uint_32)(alpha) \
2452 + (png_uint_32)(bg)*(png_uint_32)(65535L - \
75b6e0a0
GD
2453 (png_uint_32)(alpha)) + (png_uint_32)32768L); \
2454 (composite) = (png_uint_16)((temp + (temp >> 16)) >> 16); }
2455
2456#else /* standard method using integer division */
2457
2458# define png_composite(composite, fg, alpha, bg) \
2459 (composite) = (png_byte)(((png_uint_16)(fg) * (png_uint_16)(alpha) + \
2460 (png_uint_16)(bg) * (png_uint_16)(255 - (png_uint_16)(alpha)) + \
2461 (png_uint_16)127) / 255)
2462
2463# define png_composite_16(composite, fg, alpha, bg) \
2464 (composite) = (png_uint_16)(((png_uint_32)(fg) * (png_uint_32)(alpha) + \
2465 (png_uint_32)(bg)*(png_uint_32)(65535L - (png_uint_32)(alpha)) + \
2466 (png_uint_32)32767) / (png_uint_32)65535L)
2467
2468#endif /* PNG_READ_COMPOSITE_NODIV_SUPPORTED */
2469
2470/* These next functions are used internally in the code. They generally
2471 * shouldn't be used unless you are writing code to add or replace some
2472 * functionality in libpng. More information about most functions can
2473 * be found in the files where the functions are located.
2474 */
2475
2476#if defined(PNG_INTERNAL)
2477
2478/* Various modes of operation. Note that after an init, mode is set to
2479 * zero automatically when the structure is created.
2480 */
4946a942
GD
2481#define PNG_HAVE_IHDR 0x01
2482#define PNG_HAVE_PLTE 0x02
2483#define PNG_HAVE_IDAT 0x04
2484#define PNG_AFTER_IDAT 0x08
2485#define PNG_HAVE_IEND 0x10
2486#define PNG_HAVE_gAMA 0x20
2487#define PNG_HAVE_cHRM 0x40
2488#define PNG_HAVE_sRGB 0x80
2489#define PNG_HAVE_CHUNK_HEADER 0x100
2490#define PNG_WROTE_tIME 0x200
2491#define PNG_WROTE_INFO_BEFORE_PLTE 0x400
2492#define PNG_BACKGROUND_IS_GRAY 0x800
2493#define PNG_HAVE_PNG_SIGNATURE 0x1000
75b6e0a0
GD
2494
2495/* flags for the transformations the PNG library does on the image data */
2496#define PNG_BGR 0x0001
2497#define PNG_INTERLACE 0x0002
2498#define PNG_PACK 0x0004
2499#define PNG_SHIFT 0x0008
2500#define PNG_SWAP_BYTES 0x0010
2501#define PNG_INVERT_MONO 0x0020
2502#define PNG_DITHER 0x0040
2503#define PNG_BACKGROUND 0x0080
2504#define PNG_BACKGROUND_EXPAND 0x0100
2505 /* 0x0200 unused */
2506#define PNG_16_TO_8 0x0400
2507#define PNG_RGBA 0x0800
2508#define PNG_EXPAND 0x1000
2509#define PNG_GAMMA 0x2000
2510#define PNG_GRAY_TO_RGB 0x4000
4946a942 2511#define PNG_FILLER 0x8000L
75b6e0a0
GD
2512#define PNG_PACKSWAP 0x10000L
2513#define PNG_SWAP_ALPHA 0x20000L
2514#define PNG_STRIP_ALPHA 0x40000L
2515#define PNG_INVERT_ALPHA 0x80000L
2516#define PNG_USER_TRANSFORM 0x100000L
2517#define PNG_RGB_TO_GRAY_ERR 0x200000L
2518#define PNG_RGB_TO_GRAY_WARN 0x400000L
2519#define PNG_RGB_TO_GRAY 0x600000L /* two bits, RGB_TO_GRAY_ERR|WARN */
2520
2521/* flags for png_create_struct */
2522#define PNG_STRUCT_PNG 0x0001
2523#define PNG_STRUCT_INFO 0x0002
2524
2525/* Scaling factor for filter heuristic weighting calculations */
2526#define PNG_WEIGHT_SHIFT 8
2527#define PNG_WEIGHT_FACTOR (1<<(PNG_WEIGHT_SHIFT))
2528#define PNG_COST_SHIFT 3
2529#define PNG_COST_FACTOR (1<<(PNG_COST_SHIFT))
2530
2531/* flags for the png_ptr->flags rather than declaring a byte for each one */
2532#define PNG_FLAG_ZLIB_CUSTOM_STRATEGY 0x0001
2533#define PNG_FLAG_ZLIB_CUSTOM_LEVEL 0x0002
2534#define PNG_FLAG_ZLIB_CUSTOM_MEM_LEVEL 0x0004
2535#define PNG_FLAG_ZLIB_CUSTOM_WINDOW_BITS 0x0008
2536#define PNG_FLAG_ZLIB_CUSTOM_METHOD 0x0010
2537#define PNG_FLAG_ZLIB_FINISHED 0x0020
2538#define PNG_FLAG_ROW_INIT 0x0040
2539#define PNG_FLAG_FILLER_AFTER 0x0080
2540#define PNG_FLAG_CRC_ANCILLARY_USE 0x0100
2541#define PNG_FLAG_CRC_ANCILLARY_NOWARN 0x0200
2542#define PNG_FLAG_CRC_CRITICAL_USE 0x0400
2543#define PNG_FLAG_CRC_CRITICAL_IGNORE 0x0800
4946a942
GD
2544#define PNG_FLAG_FREE_PLTE 0x1000
2545#define PNG_FLAG_FREE_TRNS 0x2000
75b6e0a0 2546#define PNG_FLAG_FREE_HIST 0x4000
4946a942
GD
2547#define PNG_FLAG_KEEP_UNKNOWN_CHUNKS 0x8000L
2548#define PNG_FLAG_KEEP_UNSAFE_CHUNKS 0x10000L
2549#define PNG_FLAG_LIBRARY_MISMATCH 0x20000L
2550#define PNG_FLAG_STRIP_ERROR_NUMBERS 0x40000L
2551#define PNG_FLAG_STRIP_ERROR_TEXT 0x80000L
2552#define PNG_FLAG_MALLOC_NULL_MEM_OK 0x100000L
2553
2554/* For use in png_set_keep_unknown, png_handle_as_unknown */
2555#define HANDLE_CHUNK_AS_DEFAULT 0
2556#define HANDLE_CHUNK_NEVER 1
2557#define HANDLE_CHUNK_IF_SAFE 2
2558#define HANDLE_CHUNK_ALWAYS 3
75b6e0a0
GD
2559
2560#define PNG_FLAG_CRC_ANCILLARY_MASK (PNG_FLAG_CRC_ANCILLARY_USE | \
2561 PNG_FLAG_CRC_ANCILLARY_NOWARN)
2562
2563#define PNG_FLAG_CRC_CRITICAL_MASK (PNG_FLAG_CRC_CRITICAL_USE | \
2564 PNG_FLAG_CRC_CRITICAL_IGNORE)
2565
2566#define PNG_FLAG_CRC_MASK (PNG_FLAG_CRC_ANCILLARY_MASK | \
2567 PNG_FLAG_CRC_CRITICAL_MASK)
2568
2569/* save typing and make code easier to understand */
2570#define PNG_COLOR_DIST(c1, c2) (abs((int)((c1).red) - (int)((c2).red)) + \
2571 abs((int)((c1).green) - (int)((c2).green)) + \
2572 abs((int)((c1).blue) - (int)((c2).blue)))
2573
2574/* variables declared in png.c - only it needs to define PNG_NO_EXTERN */
2575#if !defined(PNG_NO_EXTERN) || defined(PNG_ALWAYS_EXTERN)
2576/* place to hold the signature string for a PNG file. */
4946a942
GD
2577#ifdef PNG_USE_GLOBAL_ARRAYS
2578 PNG_EXPORT_VAR (const png_byte FARDATA) png_sig[8];
2579#else
2580#define png_sig png_sig_bytes(NULL)
2581#endif
2582#endif /* PNG_NO_EXTERN */
75b6e0a0
GD
2583
2584/* Constant strings for known chunk types. If you need to add a chunk,
4946a942
GD
2585 * define the name here, and add an invocation of the macro in png.c and
2586 * wherever it's needed.
75b6e0a0 2587 */
4946a942
GD
2588#define PNG_IHDR const png_byte png_IHDR[5] = { 73, 72, 68, 82, '\0'}
2589#define PNG_IDAT const png_byte png_IDAT[5] = { 73, 68, 65, 84, '\0'}
2590#define PNG_IEND const png_byte png_IEND[5] = { 73, 69, 78, 68, '\0'}
2591#define PNG_PLTE const png_byte png_PLTE[5] = { 80, 76, 84, 69, '\0'}
2592#define PNG_bKGD const png_byte png_bKGD[5] = { 98, 75, 71, 68, '\0'}
2593#define PNG_cHRM const png_byte png_cHRM[5] = { 99, 72, 82, 77, '\0'}
2594#define PNG_gAMA const png_byte png_gAMA[5] = {103, 65, 77, 65, '\0'}
2595#define PNG_hIST const png_byte png_hIST[5] = {104, 73, 83, 84, '\0'}
2596#define PNG_iCCP const png_byte png_iCCP[5] = {105, 67, 67, 80, '\0'}
2597#define PNG_iTXt const png_byte png_iTXt[5] = {105, 84, 88, 116, '\0'}
2598#define PNG_oFFs const png_byte png_oFFs[5] = {111, 70, 70, 115, '\0'}
2599#define PNG_pCAL const png_byte png_pCAL[5] = {112, 67, 65, 76, '\0'}
2600#define PNG_sCAL const png_byte png_sCAL[5] = {115, 67, 65, 76, '\0'}
2601#define PNG_pHYs const png_byte png_pHYs[5] = {112, 72, 89, 115, '\0'}
2602#define PNG_sBIT const png_byte png_sBIT[5] = {115, 66, 73, 84, '\0'}
2603#define PNG_sPLT const png_byte png_sPLT[5] = {115, 80, 76, 84, '\0'}
2604#define PNG_sRGB const png_byte png_sRGB[5] = {115, 82, 71, 66, '\0'}
2605#define PNG_tEXt const png_byte png_tEXt[5] = {116, 69, 88, 116, '\0'}
2606#define PNG_tIME const png_byte png_tIME[5] = {116, 73, 77, 69, '\0'}
2607#define PNG_tRNS const png_byte png_tRNS[5] = {116, 82, 78, 83, '\0'}
2608#define PNG_zTXt const png_byte png_zTXt[5] = {122, 84, 88, 116, '\0'}
2609
2610#ifdef PNG_USE_GLOBAL_ARRAYS
2611PNG_EXPORT_VAR (const png_byte FARDATA) png_IHDR[5];
2612PNG_EXPORT_VAR (const png_byte FARDATA) png_IDAT[5];
2613PNG_EXPORT_VAR (const png_byte FARDATA) png_IEND[5];
2614PNG_EXPORT_VAR (const png_byte FARDATA) png_PLTE[5];
2615PNG_EXPORT_VAR (const png_byte FARDATA) png_bKGD[5];
2616PNG_EXPORT_VAR (const png_byte FARDATA) png_cHRM[5];
2617PNG_EXPORT_VAR (const png_byte FARDATA) png_gAMA[5];
2618PNG_EXPORT_VAR (const png_byte FARDATA) png_hIST[5];
2619PNG_EXPORT_VAR (const png_byte FARDATA) png_iCCP[5];
2620PNG_EXPORT_VAR (const png_byte FARDATA) png_iTXt[5];
2621PNG_EXPORT_VAR (const png_byte FARDATA) png_oFFs[5];
2622PNG_EXPORT_VAR (const png_byte FARDATA) png_pCAL[5];
2623PNG_EXPORT_VAR (const png_byte FARDATA) png_sCAL[5];
2624PNG_EXPORT_VAR (const png_byte FARDATA) png_pHYs[5];
2625PNG_EXPORT_VAR (const png_byte FARDATA) png_sBIT[5];
2626PNG_EXPORT_VAR (const png_byte FARDATA) png_sPLT[5];
2627PNG_EXPORT_VAR (const png_byte FARDATA) png_sRGB[5];
2628PNG_EXPORT_VAR (const png_byte FARDATA) png_tEXt[5];
2629PNG_EXPORT_VAR (const png_byte FARDATA) png_tIME[5];
2630PNG_EXPORT_VAR (const png_byte FARDATA) png_tRNS[5];
2631PNG_EXPORT_VAR (const png_byte FARDATA) png_zTXt[5];
2632#endif /* PNG_USE_GLOBAL_ARRAYS */
75b6e0a0 2633
75b6e0a0
GD
2634
2635/* Inline macros to do direct reads of bytes from the input buffer. These
2636 * require that you are using an architecture that uses PNG byte ordering
2637 * (MSB first) and supports unaligned data storage. I think that PowerPC
2638 * in big-endian mode and 680x0 are the only ones that will support this.
2639 * The x86 line of processors definitely do not. The png_get_int_32()
2640 * routine also assumes we are using two's complement format for negative
2641 * values, which is almost certainly true.
2642 */
2643#if defined(PNG_READ_BIG_ENDIAN_SUPPORTED)
4946a942
GD
2644# if defined(PNG_pCAL_SUPPORTED) || defined(PNG_oFFs_SUPPORTED)
2645# define png_get_int_32(buf) ( *((png_int_32p) (buf)))
2646# endif
2647# define png_get_uint_32(buf) ( *((png_uint_32p) (buf)))
2648# define png_get_uint_16(buf) ( *((png_uint_16p) (buf)))
75b6e0a0 2649#else
4946a942 2650# if defined(PNG_pCAL_SUPPORTED) || defined(PNG_oFFs_SUPPORTED)
75b6e0a0 2651PNG_EXTERN png_int_32 png_get_int_32 PNGARG((png_bytep buf));
4946a942 2652# endif
75b6e0a0
GD
2653PNG_EXTERN png_uint_32 png_get_uint_32 PNGARG((png_bytep buf));
2654PNG_EXTERN png_uint_16 png_get_uint_16 PNGARG((png_bytep buf));
4946a942 2655#endif /* !PNG_READ_BIG_ENDIAN_SUPPORTED */
75b6e0a0
GD
2656
2657/* Initialize png_ptr struct for reading, and allocate any other memory.
4946a942 2658 * (old interface - DEPRECATED - use png_create_read_struct instead).
75b6e0a0 2659 */
4946a942
GD
2660extern PNG_EXPORT(void,png_read_init) PNGARG((png_structp png_ptr));
2661#undef png_read_init
2662#define png_read_init(png_ptr) png_read_init_3(&png_ptr, \
2663 PNG_LIBPNG_VER_STRING, sizeof(png_struct));
2664extern PNG_EXPORT(void,png_read_init_3) PNGARG((png_structpp ptr_ptr,
2665 png_const_charp user_png_ver, png_size_t png_struct_size));
2666extern PNG_EXPORT(void,png_read_init_2) PNGARG((png_structp png_ptr,
2667 png_const_charp user_png_ver, png_size_t png_struct_size, png_size_t
2668 png_info_size));
75b6e0a0
GD
2669
2670/* Initialize png_ptr struct for writing, and allocate any other memory.
4946a942 2671 * (old interface - DEPRECATED - use png_create_write_struct instead).
75b6e0a0 2672 */
4946a942
GD
2673extern PNG_EXPORT(void,png_write_init) PNGARG((png_structp png_ptr));
2674#undef png_write_init
2675#define png_write_init(png_ptr) png_write_init_3(&png_ptr, \
2676 PNG_LIBPNG_VER_STRING, sizeof(png_struct));
2677extern PNG_EXPORT(void,png_write_init_3) PNGARG((png_structpp ptr_ptr,
2678 png_const_charp user_png_ver, png_size_t png_struct_size));
2679extern PNG_EXPORT(void,png_write_init_2) PNGARG((png_structp png_ptr,
2680 png_const_charp user_png_ver, png_size_t png_struct_size, png_size_t
2681 png_info_size));
2682
2683/* Allocate memory for an internal libpng struct */
75b6e0a0
GD
2684PNG_EXTERN png_voidp png_create_struct PNGARG((int type));
2685
4946a942 2686/* Free memory from internal libpng struct */
75b6e0a0
GD
2687PNG_EXTERN void png_destroy_struct PNGARG((png_voidp struct_ptr));
2688
2689PNG_EXTERN png_voidp png_create_struct_2 PNGARG((int type, png_malloc_ptr
4946a942 2690 malloc_fn, png_voidp mem_ptr));
75b6e0a0 2691PNG_EXTERN void png_destroy_struct_2 PNGARG((png_voidp struct_ptr,
4946a942 2692 png_free_ptr free_fn, png_voidp mem_ptr));
75b6e0a0 2693
4946a942 2694/* Free any memory that info_ptr points to and reset struct. */
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2695PNG_EXTERN void png_info_destroy PNGARG((png_structp png_ptr,
2696 png_infop info_ptr));
2697
4946a942 2698#ifndef PNG_1_0_X
75b6e0a0
GD
2699/* Function to allocate memory for zlib. */
2700PNG_EXTERN voidpf png_zalloc PNGARG((voidpf png_ptr, uInt items, uInt size));
2701
4946a942 2702/* Function to free memory for zlib */
75b6e0a0
GD
2703PNG_EXTERN void png_zfree PNGARG((voidpf png_ptr, voidpf ptr));
2704
4946a942
GD
2705/* Next four functions are used internally as callbacks. PNGAPI is required
2706 * but not PNG_EXPORT. PNGAPI added at libpng version 1.2.3. */
2707
2708PNG_EXTERN void PNGAPI png_default_read_data PNGARG((png_structp png_ptr,
2709 png_bytep data, png_size_t length));
2710
2711#ifdef PNG_PROGRESSIVE_READ_SUPPORTED
2712PNG_EXTERN void PNGAPI png_push_fill_buffer PNGARG((png_structp png_ptr,
2713 png_bytep buffer, png_size_t length));
2714#endif
2715
2716PNG_EXTERN void PNGAPI png_default_write_data PNGARG((png_structp png_ptr,
2717 png_bytep data, png_size_t length));
2718
2719#if defined(PNG_WRITE_FLUSH_SUPPORTED)
2720#if !defined(PNG_NO_STDIO)
2721PNG_EXTERN void PNGAPI png_default_flush PNGARG((png_structp png_ptr));
2722#endif
2723#endif
2724#else /* PNG_1_0_X */
2725#ifdef PNG_PROGRESSIVE_READ_SUPPORTED
2726PNG_EXTERN void png_push_fill_buffer PNGARG((png_structp png_ptr,
2727 png_bytep buffer, png_size_t length));
2728#endif
2729#endif /* PNG_1_0_X */
2730
2731/* Reset the CRC variable */
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2732PNG_EXTERN void png_reset_crc PNGARG((png_structp png_ptr));
2733
2734/* Write the "data" buffer to whatever output you are using. */
2735PNG_EXTERN void png_write_data PNGARG((png_structp png_ptr, png_bytep data,
2736 png_size_t length));
2737
2738/* Read data from whatever input you are using into the "data" buffer */
2739PNG_EXTERN void png_read_data PNGARG((png_structp png_ptr, png_bytep data,
2740 png_size_t length));
2741
4946a942 2742/* Read bytes into buf, and update png_ptr->crc */
75b6e0a0
GD
2743PNG_EXTERN void png_crc_read PNGARG((png_structp png_ptr, png_bytep buf,
2744 png_size_t length));
2745
4946a942
GD
2746/* Decompress data in a chunk that uses compression */
2747#if defined(PNG_zTXt_SUPPORTED) || defined(PNG_iTXt_SUPPORTED) || \
2748 defined(PNG_iCCP_SUPPORTED) || defined(PNG_sPLT_SUPPORTED)
2749PNG_EXTERN png_charp png_decompress_chunk PNGARG((png_structp png_ptr,
2750 int comp_type, png_charp chunkdata, png_size_t chunklength,
2751 png_size_t prefix_length, png_size_t *data_length));
2752#endif
2753
2754/* Read "skip" bytes, read the file crc, and (optionally) verify png_ptr->crc */
75b6e0a0
GD
2755PNG_EXTERN int png_crc_finish PNGARG((png_structp png_ptr, png_uint_32 skip));
2756
4946a942 2757/* Read the CRC from the file and compare it to the libpng calculated CRC */
75b6e0a0
GD
2758PNG_EXTERN int png_crc_error PNGARG((png_structp png_ptr));
2759
2760/* Calculate the CRC over a section of data. Note that we are only
2761 * passing a maximum of 64K on systems that have this as a memory limit,
2762 * since this is the maximum buffer size we can specify.
2763 */
2764PNG_EXTERN void png_calculate_crc PNGARG((png_structp png_ptr, png_bytep ptr,
2765 png_size_t length));
2766
2767#if defined(PNG_WRITE_FLUSH_SUPPORTED)
2768PNG_EXTERN void png_flush PNGARG((png_structp png_ptr));
2769#endif
2770
4946a942 2771
75b6e0a0
GD
2772/* Place a 32-bit number into a buffer in PNG byte order (big-endian).
2773 * The only currently known PNG chunks that use signed numbers are
2774 * the ancillary extension chunks, oFFs and pCAL.
2775 */
2776PNG_EXTERN void png_save_uint_32 PNGARG((png_bytep buf, png_uint_32 i));
2777
4946a942 2778#if defined(PNG_WRITE_pCAL_SUPPORTED) || defined(PNG_WRITE_oFFs_SUPPORTED)
75b6e0a0
GD
2779PNG_EXTERN void png_save_int_32 PNGARG((png_bytep buf, png_int_32 i));
2780#endif
2781
4946a942 2782/* Place a 16-bit number into a buffer in PNG byte order.
75b6e0a0
GD
2783 * The parameter is declared unsigned int, not png_uint_16,
2784 * just to avoid potential problems on pre-ANSI C compilers.
2785 */
2786PNG_EXTERN void png_save_uint_16 PNGARG((png_bytep buf, unsigned int i));
2787
2788/* simple function to write the signature */
2789PNG_EXTERN void png_write_sig PNGARG((png_structp png_ptr));
2790
2791/* write various chunks */
2792
2793/* Write the IHDR chunk, and update the png_struct with the necessary
2794 * information.
2795 */
2796PNG_EXTERN void png_write_IHDR PNGARG((png_structp png_ptr, png_uint_32 width,
2797 png_uint_32 height,
4946a942
GD
2798 int bit_depth, int color_type, int compression_method, int filter_method,
2799 int interlace_method));
75b6e0a0
GD
2800
2801PNG_EXTERN void png_write_PLTE PNGARG((png_structp png_ptr, png_colorp palette,
2802 png_uint_32 num_pal));
2803
2804PNG_EXTERN void png_write_IDAT PNGARG((png_structp png_ptr, png_bytep data,
2805 png_size_t length));
2806
2807PNG_EXTERN void png_write_IEND PNGARG((png_structp png_ptr));
2808
2809#if defined(PNG_WRITE_gAMA_SUPPORTED)
4946a942 2810#ifdef PNG_FLOATING_POINT_SUPPORTED
75b6e0a0
GD
2811PNG_EXTERN void png_write_gAMA PNGARG((png_structp png_ptr, double file_gamma));
2812#endif
4946a942
GD
2813#ifdef PNG_FIXED_POINT_SUPPORTED
2814PNG_EXTERN void png_write_gAMA_fixed PNGARG((png_structp png_ptr, png_fixed_point
2815 file_gamma));
2816#endif
2817#endif
75b6e0a0
GD
2818
2819#if defined(PNG_WRITE_sBIT_SUPPORTED)
2820PNG_EXTERN void png_write_sBIT PNGARG((png_structp png_ptr, png_color_8p sbit,
2821 int color_type));
2822#endif
2823
2824#if defined(PNG_WRITE_cHRM_SUPPORTED)
4946a942 2825#ifdef PNG_FLOATING_POINT_SUPPORTED
75b6e0a0
GD
2826PNG_EXTERN void png_write_cHRM PNGARG((png_structp png_ptr,
2827 double white_x, double white_y,
2828 double red_x, double red_y, double green_x, double green_y,
2829 double blue_x, double blue_y));
2830#endif
4946a942
GD
2831#ifdef PNG_FIXED_POINT_SUPPORTED
2832PNG_EXTERN void png_write_cHRM_fixed PNGARG((png_structp png_ptr,
2833 png_fixed_point int_white_x, png_fixed_point int_white_y,
2834 png_fixed_point int_red_x, png_fixed_point int_red_y, png_fixed_point
2835 int_green_x, png_fixed_point int_green_y, png_fixed_point int_blue_x,
2836 png_fixed_point int_blue_y));
2837#endif
2838#endif
75b6e0a0
GD
2839
2840#if defined(PNG_WRITE_sRGB_SUPPORTED)
2841PNG_EXTERN void png_write_sRGB PNGARG((png_structp png_ptr,
2842 int intent));
2843#endif
2844
4946a942
GD
2845#if defined(PNG_WRITE_iCCP_SUPPORTED)
2846PNG_EXTERN void png_write_iCCP PNGARG((png_structp png_ptr,
2847 png_charp name, int compression_type,
2848 png_charp profile, int proflen));
2849 /* Note to maintainer: profile should be png_bytep */
2850#endif
2851
2852#if defined(PNG_WRITE_sPLT_SUPPORTED)
2853PNG_EXTERN void png_write_sPLT PNGARG((png_structp png_ptr,
2854 png_sPLT_tp palette));
2855#endif
2856
75b6e0a0
GD
2857#if defined(PNG_WRITE_tRNS_SUPPORTED)
2858PNG_EXTERN void png_write_tRNS PNGARG((png_structp png_ptr, png_bytep trans,
2859 png_color_16p values, int number, int color_type));
2860#endif
2861
2862#if defined(PNG_WRITE_bKGD_SUPPORTED)
2863PNG_EXTERN void png_write_bKGD PNGARG((png_structp png_ptr,
2864 png_color_16p values, int color_type));
2865#endif
2866
2867#if defined(PNG_WRITE_hIST_SUPPORTED)
2868PNG_EXTERN void png_write_hIST PNGARG((png_structp png_ptr, png_uint_16p hist,
2869 int num_hist));
2870#endif
2871
4946a942
GD
2872#if defined(PNG_WRITE_TEXT_SUPPORTED) || defined(PNG_WRITE_pCAL_SUPPORTED) || \
2873 defined(PNG_WRITE_iCCP_SUPPORTED) || defined(PNG_WRITE_sPLT_SUPPORTED)
75b6e0a0
GD
2874PNG_EXTERN png_size_t png_check_keyword PNGARG((png_structp png_ptr,
2875 png_charp key, png_charpp new_key));
2876#endif
2877
2878#if defined(PNG_WRITE_tEXt_SUPPORTED)
2879PNG_EXTERN void png_write_tEXt PNGARG((png_structp png_ptr, png_charp key,
2880 png_charp text, png_size_t text_len));
2881#endif
2882
2883#if defined(PNG_WRITE_zTXt_SUPPORTED)
2884PNG_EXTERN void png_write_zTXt PNGARG((png_structp png_ptr, png_charp key,
2885 png_charp text, png_size_t text_len, int compression));
2886#endif
2887
4946a942
GD
2888#if defined(PNG_WRITE_iTXt_SUPPORTED)
2889PNG_EXTERN void png_write_iTXt PNGARG((png_structp png_ptr,
2890 int compression, png_charp key, png_charp lang, png_charp lang_key,
2891 png_charp text));
2892#endif
2893
2894#if defined(PNG_TEXT_SUPPORTED) /* Added at version 1.0.14 and 1.2.4 */
2895PNG_EXTERN int png_set_text_2 PNGARG((png_structp png_ptr,
2896 png_infop info_ptr, png_textp text_ptr, int num_text));
2897#endif
2898
75b6e0a0
GD
2899#if defined(PNG_WRITE_oFFs_SUPPORTED)
2900PNG_EXTERN void png_write_oFFs PNGARG((png_structp png_ptr,
4946a942 2901 png_int_32 x_offset, png_int_32 y_offset, int unit_type));
75b6e0a0
GD
2902#endif
2903
2904#if defined(PNG_WRITE_pCAL_SUPPORTED)
2905PNG_EXTERN void png_write_pCAL PNGARG((png_structp png_ptr, png_charp purpose,
2906 png_int_32 X0, png_int_32 X1, int type, int nparams,
2907 png_charp units, png_charpp params));
2908#endif
2909
2910#if defined(PNG_WRITE_pHYs_SUPPORTED)
2911PNG_EXTERN void png_write_pHYs PNGARG((png_structp png_ptr,
2912 png_uint_32 x_pixels_per_unit, png_uint_32 y_pixels_per_unit,
2913 int unit_type));
2914#endif
2915
2916#if defined(PNG_WRITE_tIME_SUPPORTED)
2917PNG_EXTERN void png_write_tIME PNGARG((png_structp png_ptr,
2918 png_timep mod_time));
2919#endif
2920
4946a942
GD
2921#if defined(PNG_WRITE_sCAL_SUPPORTED)
2922#if defined(PNG_FLOATING_POINT_SUPPORTED) && !defined(PNG_NO_STDIO)
2923PNG_EXTERN void png_write_sCAL PNGARG((png_structp png_ptr,
2924 int unit, double width, double height));
2925#else
2926#ifdef PNG_FIXED_POINT_SUPPORTED
2927PNG_EXTERN void png_write_sCAL_s PNGARG((png_structp png_ptr,
2928 int unit, png_charp width, png_charp height));
2929#endif
2930#endif
2931#endif
2932
75b6e0a0
GD
2933/* Called when finished processing a row of data */
2934PNG_EXTERN void png_write_finish_row PNGARG((png_structp png_ptr));
2935
2936/* Internal use only. Called before first row of data */
2937PNG_EXTERN void png_write_start_row PNGARG((png_structp png_ptr));
2938
2939#if defined(PNG_READ_GAMMA_SUPPORTED)
2940PNG_EXTERN void png_build_gamma_table PNGARG((png_structp png_ptr));
2941#endif
2942
2943/* combine a row of data, dealing with alpha, etc. if requested */
2944PNG_EXTERN void png_combine_row PNGARG((png_structp png_ptr, png_bytep row,
2945 int mask));
2946
2947#if defined(PNG_READ_INTERLACING_SUPPORTED)
2948/* expand an interlaced row */
4946a942 2949/* OLD pre-1.0.9 interface:
75b6e0a0
GD
2950PNG_EXTERN void png_do_read_interlace PNGARG((png_row_infop row_info,
2951 png_bytep row, int pass, png_uint_32 transformations));
4946a942
GD
2952 */
2953PNG_EXTERN void png_do_read_interlace PNGARG((png_structp png_ptr));
75b6e0a0
GD
2954#endif
2955
4946a942
GD
2956/* GRR TO DO (2.0 or whenever): simplify other internal calling interfaces */
2957
75b6e0a0
GD
2958#if defined(PNG_WRITE_INTERLACING_SUPPORTED)
2959/* grab pixels out of a row for an interlaced pass */
2960PNG_EXTERN void png_do_write_interlace PNGARG((png_row_infop row_info,
2961 png_bytep row, int pass));
2962#endif
2963
2964/* unfilter a row */
2965PNG_EXTERN void png_read_filter_row PNGARG((png_structp png_ptr,
2966 png_row_infop row_info, png_bytep row, png_bytep prev_row, int filter));
2967
2968/* Choose the best filter to use and filter the row data */
2969PNG_EXTERN void png_write_find_filter PNGARG((png_structp png_ptr,
2970 png_row_infop row_info));
2971
2972/* Write out the filtered row. */
2973PNG_EXTERN void png_write_filtered_row PNGARG((png_structp png_ptr,
2974 png_bytep filtered_row));
2975/* finish a row while reading, dealing with interlacing passes, etc. */
2976PNG_EXTERN void png_read_finish_row PNGARG((png_structp png_ptr));
2977
2978/* initialize the row buffers, etc. */
2979PNG_EXTERN void png_read_start_row PNGARG((png_structp png_ptr));
2980/* optional call to update the users info structure */
2981PNG_EXTERN void png_read_transform_info PNGARG((png_structp png_ptr,
2982 png_infop info_ptr));
2983
2984/* these are the functions that do the transformations */
2985#if defined(PNG_READ_FILLER_SUPPORTED)
2986PNG_EXTERN void png_do_read_filler PNGARG((png_row_infop row_info,
2987 png_bytep row, png_uint_32 filler, png_uint_32 flags));
2988#endif
2989
2990#if defined(PNG_READ_SWAP_ALPHA_SUPPORTED)
2991PNG_EXTERN void png_do_read_swap_alpha PNGARG((png_row_infop row_info,
2992 png_bytep row));
2993#endif
2994
2995#if defined(PNG_WRITE_SWAP_ALPHA_SUPPORTED)
2996PNG_EXTERN void png_do_write_swap_alpha PNGARG((png_row_infop row_info,
2997 png_bytep row));
2998#endif
2999
3000#if defined(PNG_READ_INVERT_ALPHA_SUPPORTED)
3001PNG_EXTERN void png_do_read_invert_alpha PNGARG((png_row_infop row_info,
3002 png_bytep row));
3003#endif
3004
3005#if defined(PNG_WRITE_INVERT_ALPHA_SUPPORTED)
3006PNG_EXTERN void png_do_write_invert_alpha PNGARG((png_row_infop row_info,
3007 png_bytep row));
3008#endif
3009
3010#if defined(PNG_WRITE_FILLER_SUPPORTED) || \
3011 defined(PNG_READ_STRIP_ALPHA_SUPPORTED)
3012PNG_EXTERN void png_do_strip_filler PNGARG((png_row_infop row_info,
3013 png_bytep row, png_uint_32 flags));
3014#endif
3015
3016#if defined(PNG_READ_SWAP_SUPPORTED) || defined(PNG_WRITE_SWAP_SUPPORTED)
3017PNG_EXTERN void png_do_swap PNGARG((png_row_infop row_info, png_bytep row));
3018#endif
3019
3020#if defined(PNG_READ_PACKSWAP_SUPPORTED) || defined(PNG_WRITE_PACKSWAP_SUPPORTED)
3021PNG_EXTERN void png_do_packswap PNGARG((png_row_infop row_info, png_bytep row));
3022#endif
3023
3024#if defined(PNG_READ_RGB_TO_GRAY_SUPPORTED)
3025PNG_EXTERN int png_do_rgb_to_gray PNGARG((png_structp png_ptr, png_row_infop
3026 row_info, png_bytep row));
3027#endif
3028
3029#if defined(PNG_READ_GRAY_TO_RGB_SUPPORTED)
3030PNG_EXTERN void png_do_gray_to_rgb PNGARG((png_row_infop row_info,
3031 png_bytep row));
3032#endif
3033
3034#if defined(PNG_READ_PACK_SUPPORTED)
3035PNG_EXTERN void png_do_unpack PNGARG((png_row_infop row_info, png_bytep row));
3036#endif
3037
3038#if defined(PNG_READ_SHIFT_SUPPORTED)
3039PNG_EXTERN void png_do_unshift PNGARG((png_row_infop row_info, png_bytep row,
3040 png_color_8p sig_bits));
3041#endif
3042
3043#if defined(PNG_READ_INVERT_SUPPORTED) || defined(PNG_WRITE_INVERT_SUPPORTED)
3044PNG_EXTERN void png_do_invert PNGARG((png_row_infop row_info, png_bytep row));
3045#endif
3046
3047#if defined(PNG_READ_16_TO_8_SUPPORTED)
3048PNG_EXTERN void png_do_chop PNGARG((png_row_infop row_info, png_bytep row));
3049#endif
3050
3051#if defined(PNG_READ_DITHER_SUPPORTED)
3052PNG_EXTERN void png_do_dither PNGARG((png_row_infop row_info,
3053 png_bytep row, png_bytep palette_lookup, png_bytep dither_lookup));
3054
3055# if defined(PNG_CORRECT_PALETTE_SUPPORTED)
3056PNG_EXTERN void png_correct_palette PNGARG((png_structp png_ptr,
3057 png_colorp palette, int num_palette));
3058# endif
3059#endif
3060
3061#if defined(PNG_READ_BGR_SUPPORTED) || defined(PNG_WRITE_BGR_SUPPORTED)
3062PNG_EXTERN void png_do_bgr PNGARG((png_row_infop row_info, png_bytep row));
3063#endif
3064
3065#if defined(PNG_WRITE_PACK_SUPPORTED)
3066PNG_EXTERN void png_do_pack PNGARG((png_row_infop row_info,
3067 png_bytep row, png_uint_32 bit_depth));
3068#endif
3069
3070#if defined(PNG_WRITE_SHIFT_SUPPORTED)
3071PNG_EXTERN void png_do_shift PNGARG((png_row_infop row_info, png_bytep row,
3072 png_color_8p bit_depth));
3073#endif
3074
3075#if defined(PNG_READ_BACKGROUND_SUPPORTED)
4946a942 3076#if defined(PNG_READ_GAMMA_SUPPORTED)
75b6e0a0
GD
3077PNG_EXTERN void png_do_background PNGARG((png_row_infop row_info, png_bytep row,
3078 png_color_16p trans_values, png_color_16p background,
3079 png_color_16p background_1,
3080 png_bytep gamma_table, png_bytep gamma_from_1, png_bytep gamma_to_1,
3081 png_uint_16pp gamma_16, png_uint_16pp gamma_16_from_1,
3082 png_uint_16pp gamma_16_to_1, int gamma_shift));
4946a942
GD
3083#else
3084PNG_EXTERN void png_do_background PNGARG((png_row_infop row_info, png_bytep row,
3085 png_color_16p trans_values, png_color_16p background));
3086#endif
75b6e0a0
GD
3087#endif
3088
3089#if defined(PNG_READ_GAMMA_SUPPORTED)
3090PNG_EXTERN void png_do_gamma PNGARG((png_row_infop row_info, png_bytep row,
3091 png_bytep gamma_table, png_uint_16pp gamma_16_table,
3092 int gamma_shift));
3093#endif
3094
3095#if defined(PNG_READ_EXPAND_SUPPORTED)
3096PNG_EXTERN void png_do_expand_palette PNGARG((png_row_infop row_info,
3097 png_bytep row, png_colorp palette, png_bytep trans, int num_trans));
3098PNG_EXTERN void png_do_expand PNGARG((png_row_infop row_info,
3099 png_bytep row, png_color_16p trans_value));
3100#endif
3101
3102/* The following decodes the appropriate chunks, and does error correction,
3103 * then calls the appropriate callback for the chunk if it is valid.
3104 */
3105
3106/* decode the IHDR chunk */
3107PNG_EXTERN void png_handle_IHDR PNGARG((png_structp png_ptr, png_infop info_ptr,
3108 png_uint_32 length));
3109PNG_EXTERN void png_handle_PLTE PNGARG((png_structp png_ptr, png_infop info_ptr,
3110 png_uint_32 length));
3111PNG_EXTERN void png_handle_IEND PNGARG((png_structp png_ptr, png_infop info_ptr,
3112 png_uint_32 length));
3113
4946a942
GD
3114#if defined(PNG_READ_bKGD_SUPPORTED)
3115PNG_EXTERN void png_handle_bKGD PNGARG((png_structp png_ptr, png_infop info_ptr,
75b6e0a0
GD
3116 png_uint_32 length));
3117#endif
3118
3119#if defined(PNG_READ_cHRM_SUPPORTED)
3120PNG_EXTERN void png_handle_cHRM PNGARG((png_structp png_ptr, png_infop info_ptr,
3121 png_uint_32 length));
3122#endif
3123
4946a942
GD
3124#if defined(PNG_READ_gAMA_SUPPORTED)
3125PNG_EXTERN void png_handle_gAMA PNGARG((png_structp png_ptr, png_infop info_ptr,
75b6e0a0
GD
3126 png_uint_32 length));
3127#endif
3128
4946a942
GD
3129#if defined(PNG_READ_hIST_SUPPORTED)
3130PNG_EXTERN void png_handle_hIST PNGARG((png_structp png_ptr, png_infop info_ptr,
75b6e0a0
GD
3131 png_uint_32 length));
3132#endif
3133
4946a942
GD
3134#if defined(PNG_READ_iCCP_SUPPORTED)
3135extern void png_handle_iCCP PNGARG((png_structp png_ptr, png_infop info_ptr,
75b6e0a0 3136 png_uint_32 length));
4946a942 3137#endif /* PNG_READ_iCCP_SUPPORTED */
75b6e0a0 3138
4946a942
GD
3139#if defined(PNG_READ_iTXt_SUPPORTED)
3140PNG_EXTERN void png_handle_iTXt PNGARG((png_structp png_ptr, png_infop info_ptr,
75b6e0a0
GD
3141 png_uint_32 length));
3142#endif
3143
3144#if defined(PNG_READ_oFFs_SUPPORTED)
3145PNG_EXTERN void png_handle_oFFs PNGARG((png_structp png_ptr, png_infop info_ptr,
3146 png_uint_32 length));
3147#endif
3148
3149#if defined(PNG_READ_pCAL_SUPPORTED)
3150PNG_EXTERN void png_handle_pCAL PNGARG((png_structp png_ptr, png_infop info_ptr,
3151 png_uint_32 length));
3152#endif
3153
3154#if defined(PNG_READ_pHYs_SUPPORTED)
3155PNG_EXTERN void png_handle_pHYs PNGARG((png_structp png_ptr, png_infop info_ptr,
3156 png_uint_32 length));
3157#endif
3158
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3159#if defined(PNG_READ_sBIT_SUPPORTED)
3160PNG_EXTERN void png_handle_sBIT PNGARG((png_structp png_ptr, png_infop info_ptr,
3161 png_uint_32 length));
3162#endif
3163
3164#if defined(PNG_READ_sCAL_SUPPORTED)
3165PNG_EXTERN void png_handle_sCAL PNGARG((png_structp png_ptr, png_infop info_ptr,
3166 png_uint_32 length));
3167#endif
3168
3169#if defined(PNG_READ_sPLT_SUPPORTED)
3170extern void png_handle_sPLT PNGARG((png_structp png_ptr, png_infop info_ptr,
3171 png_uint_32 length));
3172#endif /* PNG_READ_sPLT_SUPPORTED */
3173
3174#if defined(PNG_READ_sRGB_SUPPORTED)
3175PNG_EXTERN void png_handle_sRGB PNGARG((png_structp png_ptr, png_infop info_ptr,
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3176 png_uint_32 length));
3177#endif
3178
3179#if defined(PNG_READ_tEXt_SUPPORTED)
3180PNG_EXTERN void png_handle_tEXt PNGARG((png_structp png_ptr, png_infop info_ptr,
3181 png_uint_32 length));
3182#endif
3183
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3184#if defined(PNG_READ_tIME_SUPPORTED)
3185PNG_EXTERN void png_handle_tIME PNGARG((png_structp png_ptr, png_infop info_ptr,
3186 png_uint_32 length));
3187#endif
3188
3189#if defined(PNG_READ_tRNS_SUPPORTED)
3190PNG_EXTERN void png_handle_tRNS PNGARG((png_structp png_ptr, png_infop info_ptr,
3191 png_uint_32 length));
3192#endif
3193
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3194#if defined(PNG_READ_zTXt_SUPPORTED)
3195PNG_EXTERN void png_handle_zTXt PNGARG((png_structp png_ptr, png_infop info_ptr,
3196 png_uint_32 length));
3197#endif
3198
3199PNG_EXTERN void png_handle_unknown PNGARG((png_structp png_ptr,
3200 png_infop info_ptr, png_uint_32 length));
3201
3202PNG_EXTERN void png_check_chunk_name PNGARG((png_structp png_ptr,
3203 png_bytep chunk_name));
3204
3205/* handle the transformations for reading and writing */
3206PNG_EXTERN void png_do_read_transformations PNGARG((png_structp png_ptr));
3207PNG_EXTERN void png_do_write_transformations PNGARG((png_structp png_ptr));
3208
3209PNG_EXTERN void png_init_read_transformations PNGARG((png_structp png_ptr));
3210
3211#ifdef PNG_PROGRESSIVE_READ_SUPPORTED
3212PNG_EXTERN void png_push_read_chunk PNGARG((png_structp png_ptr,
3213 png_infop info_ptr));
3214PNG_EXTERN void png_push_read_sig PNGARG((png_structp png_ptr,
3215 png_infop info_ptr));
3216PNG_EXTERN void png_push_check_crc PNGARG((png_structp png_ptr));
3217PNG_EXTERN void png_push_crc_skip PNGARG((png_structp png_ptr,
3218 png_uint_32 length));
3219PNG_EXTERN void png_push_crc_finish PNGARG((png_structp png_ptr));
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3220PNG_EXTERN void png_push_save_buffer PNGARG((png_structp png_ptr));
3221PNG_EXTERN void png_push_restore_buffer PNGARG((png_structp png_ptr,
3222 png_bytep buffer, png_size_t buffer_length));
3223PNG_EXTERN void png_push_read_IDAT PNGARG((png_structp png_ptr));
3224PNG_EXTERN void png_process_IDAT_data PNGARG((png_structp png_ptr,
3225 png_bytep buffer, png_size_t buffer_length));
3226PNG_EXTERN void png_push_process_row PNGARG((png_structp png_ptr));
3227PNG_EXTERN void png_push_handle_unknown PNGARG((png_structp png_ptr,
3228 png_infop info_ptr, png_uint_32 length));
3229PNG_EXTERN void png_push_have_info PNGARG((png_structp png_ptr,
3230 png_infop info_ptr));
3231PNG_EXTERN void png_push_have_end PNGARG((png_structp png_ptr,
3232 png_infop info_ptr));
3233PNG_EXTERN void png_push_have_row PNGARG((png_structp png_ptr, png_bytep row));
3234PNG_EXTERN void png_push_read_end PNGARG((png_structp png_ptr,
3235 png_infop info_ptr));
3236PNG_EXTERN void png_process_some_data PNGARG((png_structp png_ptr,
3237 png_infop info_ptr));
3238PNG_EXTERN void png_read_push_finish_row PNGARG((png_structp png_ptr));
3239#if defined(PNG_READ_tEXt_SUPPORTED)
3240PNG_EXTERN void png_push_handle_tEXt PNGARG((png_structp png_ptr,
3241 png_infop info_ptr, png_uint_32 length));
3242PNG_EXTERN void png_push_read_tEXt PNGARG((png_structp png_ptr,
3243 png_infop info_ptr));
3244#endif
3245#if defined(PNG_READ_zTXt_SUPPORTED)
3246PNG_EXTERN void png_push_handle_zTXt PNGARG((png_structp png_ptr,
3247 png_infop info_ptr, png_uint_32 length));
3248PNG_EXTERN void png_push_read_zTXt PNGARG((png_structp png_ptr,
3249 png_infop info_ptr));
3250#endif
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3251#if defined(PNG_READ_iTXt_SUPPORTED)
3252PNG_EXTERN void png_push_handle_iTXt PNGARG((png_structp png_ptr,
3253 png_infop info_ptr, png_uint_32 length));
3254PNG_EXTERN void png_push_read_iTXt PNGARG((png_structp png_ptr,
3255 png_infop info_ptr));
3256#endif
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3257
3258#endif /* PNG_PROGRESSIVE_READ_SUPPORTED */
3259
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3260#ifdef PNG_MNG_FEATURES_SUPPORTED
3261PNG_EXTERN void png_do_read_intrapixel PNGARG((png_row_infop row_info,
3262 png_bytep row));
3263PNG_EXTERN void png_do_write_intrapixel PNGARG((png_row_infop row_info,
3264 png_bytep row));
3265#endif
3266
3267#if defined(PNG_ASSEMBLER_CODE_SUPPORTED)
3268/* png.c */ /* PRIVATE */
3269PNG_EXTERN void png_init_mmx_flags PNGARG((png_structp png_ptr));
3270#endif
3271/* Maintainer: Put new private prototypes here ^ and in libpngpf.3 */
3272
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3273#endif /* PNG_INTERNAL */
3274
3275#ifdef __cplusplus
3276}
3277#endif
3278
4946a942 3279#endif /* PNG_VERSION_INFO_ONLY */
75b6e0a0 3280/* do not put anything past this line */
4946a942 3281#endif /* PNG_H */