1/* 2 * DO NOT ALTER OR REMOVE COPYRIGHT NOTICES OR THIS FILE HEADER. 3 * 4 * This code is free software; you can redistribute it and/or modify it 5 * under the terms of the GNU General Public License version 2 only, as 6 * published by the Free Software Foundation. Oracle designates this 7 * particular file as subject to the "Classpath" exception as provided 8 * by Oracle in the LICENSE file that accompanied this code. 9 * 10 * This code is distributed in the hope that it will be useful, but WITHOUT 11 * ANY WARRANTY; without even the implied warranty of MERCHANTABILITY or 12 * FITNESS FOR A PARTICULAR PURPOSE. See the GNU General Public License 13 * version 2 for more details (a copy is included in the LICENSE file that 14 * accompanied this code). 15 * 16 * You should have received a copy of the GNU General Public License version 17 * 2 along with this work; if not, write to the Free Software Foundation, 18 * Inc., 51 Franklin St, Fifth Floor, Boston, MA 02110-1301 USA. 19 * 20 * Please contact Oracle, 500 Oracle Parkway, Redwood Shores, CA 94065 USA 21 * or visit www.oracle.com if you need additional information or have any 22 * questions. 23 */ 24 25/* png.h - header file for PNG reference library 26 * 27 * This file is available under and governed by the GNU General Public 28 * License version 2 only, as published by the Free Software Foundation. 29 * However, the following notice accompanied the original version of this 30 * file and, per its terms, should not be removed: 31 * 32 * libpng version 1.6.28, January 5, 2017 33 * 34 * Copyright (c) 1998-2002,2004,2006-2017 Glenn Randers-Pehrson 35 * (Version 0.96 Copyright (c) 1996, 1997 Andreas Dilger) 36 * (Version 0.88 Copyright (c) 1995, 1996 Guy Eric Schalnat, Group 42, Inc.) 37 * 38 * This code is released under the libpng license (See LICENSE, below) 39 * 40 * Authors and maintainers: 41 * libpng versions 0.71, May 1995, through 0.88, January 1996: Guy Schalnat 42 * libpng versions 0.89, June 1996, through 0.96, May 1997: Andreas Dilger 43 * libpng versions 0.97, January 1998, through 1.6.28, January 5, 2017: 44 * Glenn Randers-Pehrson. 45 * See also "Contributing Authors", below. 46 */ 47 48/* 49 * COPYRIGHT NOTICE, DISCLAIMER, and LICENSE: 50 * 51 * If you modify libpng you may insert additional notices immediately following 52 * this sentence. 53 * 54 * This code is released under the libpng license. 55 * 56 * libpng versions 1.0.7, July 1, 2000 through 1.6.28, January 5, 2017 are 57 * Copyright (c) 2000-2002, 2004, 2006-2017 Glenn Randers-Pehrson, are 58 * derived from libpng-1.0.6, and are distributed according to the same 59 * disclaimer and license as libpng-1.0.6 with the following individuals 60 * added to the list of Contributing Authors: 61 * 62 * Simon-Pierre Cadieux 63 * Eric S. Raymond 64 * Mans Rullgard 65 * Cosmin Truta 66 * Gilles Vollant 67 * James Yu 68 * Mandar Sahastrabuddhe 69 * 70 * and with the following additions to the disclaimer: 71 * 72 * There is no warranty against interference with your enjoyment of the 73 * library or against infringement. There is no warranty that our 74 * efforts or the library will fulfill any of your particular purposes 75 * or needs. This library is provided with all faults, and the entire 76 * risk of satisfactory quality, performance, accuracy, and effort is with 77 * the user. 78 * 79 * Some files in the "contrib" directory and some configure-generated 80 * files that are distributed with libpng have other copyright owners and 81 * are released under other open source licenses. 82 * 83 * libpng versions 0.97, January 1998, through 1.0.6, March 20, 2000, are 84 * Copyright (c) 1998-2000 Glenn Randers-Pehrson, are derived from 85 * libpng-0.96, and are distributed according to the same disclaimer and 86 * license as libpng-0.96, with the following individuals added to the list 87 * of Contributing Authors: 88 * 89 * Tom Lane 90 * Glenn Randers-Pehrson 91 * Willem van Schaik 92 * 93 * libpng versions 0.89, June 1996, through 0.96, May 1997, are 94 * Copyright (c) 1996-1997 Andreas Dilger, are derived from libpng-0.88, 95 * and are distributed according to the same disclaimer and license as 96 * libpng-0.88, with the following individuals added to the list of 97 * Contributing Authors: 98 * 99 * John Bowler 100 * Kevin Bracey 101 * Sam Bushell 102 * Magnus Holmgren 103 * Greg Roelofs 104 * Tom Tanner 105 * 106 * Some files in the "scripts" directory have other copyright owners 107 * but are released under this license. 108 * 109 * libpng versions 0.5, May 1995, through 0.88, January 1996, are 110 * Copyright (c) 1995-1996 Guy Eric Schalnat, Group 42, Inc. 111 * 112 * For the purposes of this copyright and license, "Contributing Authors" 113 * is defined as the following set of individuals: 114 * 115 * Andreas Dilger 116 * Dave Martindale 117 * Guy Eric Schalnat 118 * Paul Schmidt 119 * Tim Wegner 120 * 121 * The PNG Reference Library is supplied "AS IS". The Contributing Authors 122 * and Group 42, Inc. disclaim all warranties, expressed or implied, 123 * including, without limitation, the warranties of merchantability and of 124 * fitness for any purpose. The Contributing Authors and Group 42, Inc. 125 * assume no liability for direct, indirect, incidental, special, exemplary, 126 * or consequential damages, which may result from the use of the PNG 127 * Reference Library, even if advised of the possibility of such damage. 128 * 129 * Permission is hereby granted to use, copy, modify, and distribute this 130 * source code, or portions hereof, for any purpose, without fee, subject 131 * to the following restrictions: 132 * 133 * 1. The origin of this source code must not be misrepresented. 134 * 135 * 2. Altered versions must be plainly marked as such and must not 136 * be misrepresented as being the original source. 137 * 138 * 3. This Copyright notice may not be removed or altered from any 139 * source or altered source distribution. 140 * 141 * The Contributing Authors and Group 42, Inc. specifically permit, without 142 * fee, and encourage the use of this source code as a component to 143 * supporting the PNG file format in commercial products. If you use this 144 * source code in a product, acknowledgment is not required but would be 145 * appreciated. 146 * 147 * END OF COPYRIGHT NOTICE, DISCLAIMER, and LICENSE. 148 * 149 * TRADEMARK: 150 * 151 * The name "libpng" has not been registered by the Copyright owner 152 * as a trademark in any jurisdiction. However, because libpng has 153 * been distributed and maintained world-wide, continually since 1995, 154 * the Copyright owner claims "common-law trademark protection" in any 155 * jurisdiction where common-law trademark is recognized. 156 * 157 * OSI CERTIFICATION: 158 * 159 * Libpng is OSI Certified Open Source Software. OSI Certified Open Source is 160 * a certification mark of the Open Source Initiative. OSI has not addressed 161 * the additional disclaimers inserted at version 1.0.7. 162 * 163 * EXPORT CONTROL: 164 * 165 * The Copyright owner believes that the Export Control Classification 166 * Number (ECCN) for libpng is EAR99, which means not subject to export 167 * controls or International Traffic in Arms Regulations (ITAR) because 168 * it is open source, publicly available software, that does not contain 169 * any encryption software. See the EAR, paragraphs 734.3(b)(3) and 170 * 734.7(b). 171 */ 172 173/* 174 * A "png_get_copyright" function is available, for convenient use in "about" 175 * boxes and the like: 176 * 177 * printf("%s", png_get_copyright(NULL)); 178 * 179 * Also, the PNG logo (in PNG format, of course) is supplied in the 180 * files "pngbar.png" and "pngbar.jpg (88x31) and "pngnow.png" (98x31). 181 */ 182 183/* 184 * The contributing authors would like to thank all those who helped 185 * with testing, bug fixes, and patience. This wouldn't have been 186 * possible without all of you. 187 * 188 * Thanks to Frank J. T. Wojcik for helping with the documentation. 189 */ 190 191/* Note about libpng version numbers: 192 * 193 * Due to various miscommunications, unforeseen code incompatibilities 194 * and occasional factors outside the authors' control, version numbering 195 * on the library has not always been consistent and straightforward. 196 * The following table summarizes matters since version 0.89c, which was 197 * the first widely used release: 198 * 199 * source png.h png.h shared-lib 200 * version string int version 201 * ------- ------ ----- ---------- 202 * 0.89c "1.0 beta 3" 0.89 89 1.0.89 203 * 0.90 "1.0 beta 4" 0.90 90 0.90 [should have been 2.0.90] 204 * 0.95 "1.0 beta 5" 0.95 95 0.95 [should have been 2.0.95] 205 * 0.96 "1.0 beta 6" 0.96 96 0.96 [should have been 2.0.96] 206 * 0.97b "1.00.97 beta 7" 1.00.97 97 1.0.1 [should have been 2.0.97] 207 * 0.97c 0.97 97 2.0.97 208 * 0.98 0.98 98 2.0.98 209 * 0.99 0.99 98 2.0.99 210 * 0.99a-m 0.99 99 2.0.99 211 * 1.00 1.00 100 2.1.0 [100 should be 10000] 212 * 1.0.0 (from here on, the 100 2.1.0 [100 should be 10000] 213 * 1.0.1 png.h string is 10001 2.1.0 214 * 1.0.1a-e identical to the 10002 from here on, the shared library 215 * 1.0.2 source version) 10002 is 2.V where V is the source code 216 * 1.0.2a-b 10003 version, except as noted. 217 * 1.0.3 10003 218 * 1.0.3a-d 10004 219 * 1.0.4 10004 220 * 1.0.4a-f 10005 221 * 1.0.5 (+ 2 patches) 10005 222 * 1.0.5a-d 10006 223 * 1.0.5e-r 10100 (not source compatible) 224 * 1.0.5s-v 10006 (not binary compatible) 225 * 1.0.6 (+ 3 patches) 10006 (still binary incompatible) 226 * 1.0.6d-f 10007 (still binary incompatible) 227 * 1.0.6g 10007 228 * 1.0.6h 10007 10.6h (testing xy.z so-numbering) 229 * 1.0.6i 10007 10.6i 230 * 1.0.6j 10007 2.1.0.6j (incompatible with 1.0.0) 231 * 1.0.7beta11-14 DLLNUM 10007 2.1.0.7beta11-14 (binary compatible) 232 * 1.0.7beta15-18 1 10007 2.1.0.7beta15-18 (binary compatible) 233 * 1.0.7rc1-2 1 10007 2.1.0.7rc1-2 (binary compatible) 234 * 1.0.7 1 10007 (still compatible) 235 * ... 236 * 1.0.19 10 10019 10.so.0.19[.0] 237 * ... 238 * 1.2.57 13 10257 12.so.0.57[.0] 239 * ... 240 * 1.5.28 15 10527 15.so.15.28[.0] 241 * ... 242 * 1.6.28 16 10628 16.so.16.28[.0] 243 * 244 * Henceforth the source version will match the shared-library major 245 * and minor numbers; the shared-library major version number will be 246 * used for changes in backward compatibility, as it is intended. The 247 * PNG_LIBPNG_VER macro, which is not used within libpng but is available 248 * for applications, is an unsigned integer of the form xyyzz corresponding 249 * to the source version x.y.z (leading zeros in y and z). Beta versions 250 * were given the previous public release number plus a letter, until 251 * version 1.0.6j; from then on they were given the upcoming public 252 * release number plus "betaNN" or "rcNN". 253 * 254 * Binary incompatibility exists only when applications make direct access 255 * to the info_ptr or png_ptr members through png.h, and the compiled 256 * application is loaded with a different version of the library. 257 * 258 * DLLNUM will change each time there are forward or backward changes 259 * in binary compatibility (e.g., when a new feature is added). 260 * 261 * See libpng.txt or libpng.3 for more information. The PNG specification 262 * is available as a W3C Recommendation and as an ISO Specification, 263 * <http://www.w3.org/TR/2003/REC-PNG-20031110/ 264 */ 265 266/* 267 * Y2K compliance in libpng: 268 * ========================= 269 * 270 * January 5, 2017 271 * 272 * Since the PNG Development group is an ad-hoc body, we can't make 273 * an official declaration. 274 * 275 * This is your unofficial assurance that libpng from version 0.71 and 276 * upward through 1.6.28 are Y2K compliant. It is my belief that 277 * earlier versions were also Y2K compliant. 278 * 279 * Libpng only has two year fields. One is a 2-byte unsigned integer 280 * that will hold years up to 65535. The other, which is deprecated, 281 * holds the date in text format, and will hold years up to 9999. 282 * 283 * The integer is 284 * "png_uint_16 year" in png_time_struct. 285 * 286 * The string is 287 * "char time_buffer[29]" in png_struct. This is no longer used 288 * in libpng-1.6.x and will be removed from libpng-1.7.0. 289 * 290 * There are seven time-related functions: 291 * png.c: png_convert_to_rfc_1123_buffer() in png.c 292 * (formerly png_convert_to_rfc_1123() prior to libpng-1.5.x and 293 * png_convert_to_rfc_1152() in error prior to libpng-0.98) 294 * png_convert_from_struct_tm() in pngwrite.c, called in pngwrite.c 295 * png_convert_from_time_t() in pngwrite.c 296 * png_get_tIME() in pngget.c 297 * png_handle_tIME() in pngrutil.c, called in pngread.c 298 * png_set_tIME() in pngset.c 299 * png_write_tIME() in pngwutil.c, called in pngwrite.c 300 * 301 * All handle dates properly in a Y2K environment. The 302 * png_convert_from_time_t() function calls gmtime() to convert from system 303 * clock time, which returns (year - 1900), which we properly convert to 304 * the full 4-digit year. There is a possibility that libpng applications 305 * are not passing 4-digit years into the png_convert_to_rfc_1123_buffer() 306 * function, or that they are incorrectly passing only a 2-digit year 307 * instead of "year - 1900" into the png_convert_from_struct_tm() function, 308 * but this is not under our control. The libpng documentation has always 309 * stated that it works with 4-digit years, and the APIs have been 310 * documented as such. 311 * 312 * The tIME chunk itself is also Y2K compliant. It uses a 2-byte unsigned 313 * integer to hold the year, and can hold years as large as 65535. 314 * 315 * zlib, upon which libpng depends, is also Y2K compliant. It contains 316 * no date-related code. 317 * 318 * Glenn Randers-Pehrson 319 * libpng maintainer 320 * PNG Development Group 321 */ 322 323#ifndef PNG_H 324#define PNG_H 325 326/* This is not the place to learn how to use libpng. The file libpng-manual.txt 327 * describes how to use libpng, and the file example.c summarizes it 328 * with some code on which to build. This file is useful for looking 329 * at the actual function definitions and structure components. If that 330 * file has been stripped from your copy of libpng, you can find it at 331 * <http://www.libpng.org/pub/png/libpng-manual.txt> 332 * 333 * If you just need to read a PNG file and don't want to read the documentation 334 * skip to the end of this file and read the section entitled 'simplified API'. 335 */ 336 337/* Version information for png.h - this should match the version in png.c */ 338#define PNG_LIBPNG_VER_STRING "1.6.28" 339#define PNG_HEADER_VERSION_STRING " libpng version 1.6.28 - January 5, 2017\n" 340 341#define PNG_LIBPNG_VER_SONUM 16 342#define PNG_LIBPNG_VER_DLLNUM 16 343 344/* These should match the first 3 components of PNG_LIBPNG_VER_STRING: */ 345#define PNG_LIBPNG_VER_MAJOR 1 346#define PNG_LIBPNG_VER_MINOR 6 347#define PNG_LIBPNG_VER_RELEASE 28 348 349/* This should match the numeric part of the final component of 350 * PNG_LIBPNG_VER_STRING, omitting any leading zero: 351 */ 352 353#define PNG_LIBPNG_VER_BUILD 0 354 355/* Release Status */ 356#define PNG_LIBPNG_BUILD_ALPHA 1 357#define PNG_LIBPNG_BUILD_BETA 2 358#define PNG_LIBPNG_BUILD_RC 3 359#define PNG_LIBPNG_BUILD_STABLE 4 360#define PNG_LIBPNG_BUILD_RELEASE_STATUS_MASK 7 361 362/* Release-Specific Flags */ 363#define PNG_LIBPNG_BUILD_PATCH 8 /* Can be OR'ed with 364 PNG_LIBPNG_BUILD_STABLE only */ 365#define PNG_LIBPNG_BUILD_PRIVATE 16 /* Cannot be OR'ed with 366 PNG_LIBPNG_BUILD_SPECIAL */ 367#define PNG_LIBPNG_BUILD_SPECIAL 32 /* Cannot be OR'ed with 368 PNG_LIBPNG_BUILD_PRIVATE */ 369 370#define PNG_LIBPNG_BUILD_BASE_TYPE PNG_LIBPNG_BUILD_STABLE 371 372/* Careful here. At one time, Guy wanted to use 082, but that would be octal. 373 * We must not include leading zeros. 374 * Versions 0.7 through 1.0.0 were in the range 0 to 100 here (only 375 * version 1.0.0 was mis-numbered 100 instead of 10000). From 376 * version 1.0.1 it's xxyyzz, where x=major, y=minor, z=release 377 */ 378#define PNG_LIBPNG_VER 10628 /* 1.6.28 */ 379 380/* Library configuration: these options cannot be changed after 381 * the library has been built. 382 */ 383#ifndef PNGLCONF_H 384/* If pnglibconf.h is missing, you can 385 * copy scripts/pnglibconf.h.prebuilt to pnglibconf.h 386 */ 387# include "pnglibconf.h" 388#endif 389 390#ifndef PNG_VERSION_INFO_ONLY 391/* Machine specific configuration. */ 392# include "pngconf.h" 393#endif 394 395/* 396 * Added at libpng-1.2.8 397 * 398 * Ref MSDN: Private as priority over Special 399 * VS_FF_PRIVATEBUILD File *was not* built using standard release 400 * procedures. If this value is given, the StringFileInfo block must 401 * contain a PrivateBuild string. 402 * 403 * VS_FF_SPECIALBUILD File *was* built by the original company using 404 * standard release procedures but is a variation of the standard 405 * file of the same version number. If this value is given, the 406 * StringFileInfo block must contain a SpecialBuild string. 407 */ 408 409#ifdef PNG_USER_PRIVATEBUILD /* From pnglibconf.h */ 410# define PNG_LIBPNG_BUILD_TYPE \ 411 (PNG_LIBPNG_BUILD_BASE_TYPE | PNG_LIBPNG_BUILD_PRIVATE) 412#else 413# ifdef PNG_LIBPNG_SPECIALBUILD 414# define PNG_LIBPNG_BUILD_TYPE \ 415 (PNG_LIBPNG_BUILD_BASE_TYPE | PNG_LIBPNG_BUILD_SPECIAL) 416# else 417# define PNG_LIBPNG_BUILD_TYPE (PNG_LIBPNG_BUILD_BASE_TYPE) 418# endif 419#endif 420 421#ifndef PNG_VERSION_INFO_ONLY 422 423/* Inhibit C++ name-mangling for libpng functions but not for system calls. */ 424#ifdef __cplusplus 425extern "C" { 426#endif /* __cplusplus */ 427 428/* Version information for C files, stored in png.c. This had better match 429 * the version above. 430 */ 431#define png_libpng_ver png_get_header_ver(NULL) 432 433/* This file is arranged in several sections: 434 * 435 * 1. [omitted] 436 * 2. Any configuration options that can be specified by for the application 437 * code when it is built. (Build time configuration is in pnglibconf.h) 438 * 3. Type definitions (base types are defined in pngconf.h), structure 439 * definitions. 440 * 4. Exported library functions. 441 * 5. Simplified API. 442 * 6. Implementation options. 443 * 444 * The library source code has additional files (principally pngpriv.h) that 445 * allow configuration of the library. 446 */ 447 448/* Section 1: [omitted] */ 449 450/* Section 2: run time configuration 451 * See pnglibconf.h for build time configuration 452 * 453 * Run time configuration allows the application to choose between 454 * implementations of certain arithmetic APIs. The default is set 455 * at build time and recorded in pnglibconf.h, but it is safe to 456 * override these (and only these) settings. Note that this won't 457 * change what the library does, only application code, and the 458 * settings can (and probably should) be made on a per-file basis 459 * by setting the #defines before including png.h 460 * 461 * Use macros to read integers from PNG data or use the exported 462 * functions? 463 * PNG_USE_READ_MACROS: use the macros (see below) Note that 464 * the macros evaluate their argument multiple times. 465 * PNG_NO_USE_READ_MACROS: call the relevant library function. 466 * 467 * Use the alternative algorithm for compositing alpha samples that 468 * does not use division? 469 * PNG_READ_COMPOSITE_NODIV_SUPPORTED: use the 'no division' 470 * algorithm. 471 * PNG_NO_READ_COMPOSITE_NODIV: use the 'division' algorithm. 472 * 473 * How to handle benign errors if PNG_ALLOW_BENIGN_ERRORS is 474 * false? 475 * PNG_ALLOW_BENIGN_ERRORS: map calls to the benign error 476 * APIs to png_warning. 477 * Otherwise the calls are mapped to png_error. 478 */ 479 480/* Section 3: type definitions, including structures and compile time 481 * constants. 482 * See pngconf.h for base types that vary by machine/system 483 */ 484 485/* This triggers a compiler error in png.c, if png.c and png.h 486 * do not agree upon the version number. 487 */ 488typedef char* png_libpng_version_1_6_28; 489 490/* Basic control structions. Read libpng-manual.txt or libpng.3 for more info. 491 * 492 * png_struct is the cache of information used while reading or writing a single 493 * PNG file. One of these is always required, although the simplified API 494 * (below) hides the creation and destruction of it. 495 */ 496typedef struct png_struct_def png_struct; 497typedef const png_struct * png_const_structp; 498typedef png_struct * png_structp; 499typedef png_struct * * png_structpp; 500 501/* png_info contains information read from or to be written to a PNG file. One 502 * or more of these must exist while reading or creating a PNG file. The 503 * information is not used by libpng during read but is used to control what 504 * gets written when a PNG file is created. "png_get_" function calls read 505 * information during read and "png_set_" functions calls write information 506 * when creating a PNG. 507 * been moved into a separate header file that is not accessible to 508 * applications. Read libpng-manual.txt or libpng.3 for more info. 509 */ 510typedef struct png_info_def png_info; 511typedef png_info * png_infop; 512typedef const png_info * png_const_infop; 513typedef png_info * * png_infopp; 514 515/* Types with names ending 'p' are pointer types. The corresponding types with 516 * names ending 'rp' are identical pointer types except that the pointer is 517 * marked 'restrict', which means that it is the only pointer to the object 518 * passed to the function. Applications should not use the 'restrict' types; 519 * it is always valid to pass 'p' to a pointer with a function argument of the 520 * corresponding 'rp' type. Different compilers have different rules with 521 * regard to type matching in the presence of 'restrict'. For backward 522 * compatibility libpng callbacks never have 'restrict' in their parameters and, 523 * consequentially, writing portable application code is extremely difficult if 524 * an attempt is made to use 'restrict'. 525 */ 526typedef png_struct * PNG_RESTRICT png_structrp; 527typedef const png_struct * PNG_RESTRICT png_const_structrp; 528typedef png_info * PNG_RESTRICT png_inforp; 529typedef const png_info * PNG_RESTRICT png_const_inforp; 530 531/* Three color definitions. The order of the red, green, and blue, (and the 532 * exact size) is not important, although the size of the fields need to 533 * be png_byte or png_uint_16 (as defined below). 534 */ 535typedef struct png_color_struct 536{ 537 png_byte red; 538 png_byte green; 539 png_byte blue; 540} png_color; 541typedef png_color * png_colorp; 542typedef const png_color * png_const_colorp; 543typedef png_color * * png_colorpp; 544 545typedef struct png_color_16_struct 546{ 547 png_byte index; /* used for palette files */ 548 png_uint_16 red; /* for use in red green blue files */ 549 png_uint_16 green; 550 png_uint_16 blue; 551 png_uint_16 gray; /* for use in grayscale files */ 552} png_color_16; 553typedef png_color_16 * png_color_16p; 554typedef const png_color_16 * png_const_color_16p; 555typedef png_color_16 * * png_color_16pp; 556 557typedef struct png_color_8_struct 558{ 559 png_byte red; /* for use in red green blue files */ 560 png_byte green; 561 png_byte blue; 562 png_byte gray; /* for use in grayscale files */ 563 png_byte alpha; /* for alpha channel files */ 564} png_color_8; 565typedef png_color_8 * png_color_8p; 566typedef const png_color_8 * png_const_color_8p; 567typedef png_color_8 * * png_color_8pp; 568 569/* 570 * The following two structures are used for the in-core representation 571 * of sPLT chunks. 572 */ 573typedef struct png_sPLT_entry_struct 574{ 575 png_uint_16 red; 576 png_uint_16 green; 577 png_uint_16 blue; 578 png_uint_16 alpha; 579 png_uint_16 frequency; 580} png_sPLT_entry; 581typedef png_sPLT_entry * png_sPLT_entryp; 582typedef const png_sPLT_entry * png_const_sPLT_entryp; 583typedef png_sPLT_entry * * png_sPLT_entrypp; 584 585/* When the depth of the sPLT palette is 8 bits, the color and alpha samples 586 * occupy the LSB of their respective members, and the MSB of each member 587 * is zero-filled. The frequency member always occupies the full 16 bits. 588 */ 589 590typedef struct png_sPLT_struct 591{ 592 png_charp name; /* palette name */ 593 png_byte depth; /* depth of palette samples */ 594 png_sPLT_entryp entries; /* palette entries */ 595 png_int_32 nentries; /* number of palette entries */ 596} png_sPLT_t; 597typedef png_sPLT_t * png_sPLT_tp; 598typedef const png_sPLT_t * png_const_sPLT_tp; 599typedef png_sPLT_t * * png_sPLT_tpp; 600 601#ifdef PNG_TEXT_SUPPORTED 602/* png_text holds the contents of a text/ztxt/itxt chunk in a PNG file, 603 * and whether that contents is compressed or not. The "key" field 604 * points to a regular zero-terminated C string. The "text" fields can be a 605 * regular C string, an empty string, or a NULL pointer. 606 * However, the structure returned by png_get_text() will always contain 607 * the "text" field as a regular zero-terminated C string (possibly 608 * empty), never a NULL pointer, so it can be safely used in printf() and 609 * other string-handling functions. Note that the "itxt_length", "lang", and 610 * "lang_key" members of the structure only exist when the library is built 611 * with iTXt chunk support. Prior to libpng-1.4.0 the library was built by 612 * default without iTXt support. Also note that when iTXt *is* supported, 613 * the "lang" and "lang_key" fields contain NULL pointers when the 614 * "compression" field contains * PNG_TEXT_COMPRESSION_NONE or 615 * PNG_TEXT_COMPRESSION_zTXt. Note that the "compression value" is not the 616 * same as what appears in the PNG tEXt/zTXt/iTXt chunk's "compression flag" 617 * which is always 0 or 1, or its "compression method" which is always 0. 618 */ 619typedef struct png_text_struct 620{ 621 int compression; /* compression value: 622 -1: tEXt, none 623 0: zTXt, deflate 624 1: iTXt, none 625 2: iTXt, deflate */ 626 png_charp key; /* keyword, 1-79 character description of "text" */ 627 png_charp text; /* comment, may be an empty string (ie "") 628 or a NULL pointer */ 629 png_size_t text_length; /* length of the text string */ 630 png_size_t itxt_length; /* length of the itxt string */ 631 png_charp lang; /* language code, 0-79 characters 632 or a NULL pointer */ 633 png_charp lang_key; /* keyword translated UTF-8 string, 0 or more 634 chars or a NULL pointer */ 635} png_text; 636typedef png_text * png_textp; 637typedef const png_text * png_const_textp; 638typedef png_text * * png_textpp; 639#endif 640 641/* Supported compression types for text in PNG files (tEXt, and zTXt). 642 * The values of the PNG_TEXT_COMPRESSION_ defines should NOT be changed. */ 643#define PNG_TEXT_COMPRESSION_NONE_WR -3 644#define PNG_TEXT_COMPRESSION_zTXt_WR -2 645#define PNG_TEXT_COMPRESSION_NONE -1 646#define PNG_TEXT_COMPRESSION_zTXt 0 647#define PNG_ITXT_COMPRESSION_NONE 1 648#define PNG_ITXT_COMPRESSION_zTXt 2 649#define PNG_TEXT_COMPRESSION_LAST 3 /* Not a valid value */ 650 651/* png_time is a way to hold the time in an machine independent way. 652 * Two conversions are provided, both from time_t and struct tm. There 653 * is no portable way to convert to either of these structures, as far 654 * as I know. If you know of a portable way, send it to me. As a side 655 * note - PNG has always been Year 2000 compliant! 656 */ 657typedef struct png_time_struct 658{ 659 png_uint_16 year; /* full year, as in, 1995 */ 660 png_byte month; /* month of year, 1 - 12 */ 661 png_byte day; /* day of month, 1 - 31 */ 662 png_byte hour; /* hour of day, 0 - 23 */ 663 png_byte minute; /* minute of hour, 0 - 59 */ 664 png_byte second; /* second of minute, 0 - 60 (for leap seconds) */ 665} png_time; 666typedef png_time * png_timep; 667typedef const png_time * png_const_timep; 668typedef png_time * * png_timepp; 669 670#if defined(PNG_STORE_UNKNOWN_CHUNKS_SUPPORTED) ||\ 671 defined(PNG_USER_CHUNKS_SUPPORTED) 672/* png_unknown_chunk is a structure to hold queued chunks for which there is 673 * no specific support. The idea is that we can use this to queue 674 * up private chunks for output even though the library doesn't actually 675 * know about their semantics. 676 * 677 * The data in the structure is set by libpng on read and used on write. 678 */ 679typedef struct png_unknown_chunk_t 680{ 681 png_byte name[5]; /* Textual chunk name with '\0' terminator */ 682 png_byte *data; /* Data, should not be modified on read! */ 683 png_size_t size; 684 685 /* On write 'location' must be set using the flag values listed below. 686 * Notice that on read it is set by libpng however the values stored have 687 * more bits set than are listed below. Always treat the value as a 688 * bitmask. On write set only one bit - setting multiple bits may cause the 689 * chunk to be written in multiple places. 690 */ 691 png_byte location; /* mode of operation at read time */ 692} 693png_unknown_chunk; 694 695typedef png_unknown_chunk * png_unknown_chunkp; 696typedef const png_unknown_chunk * png_const_unknown_chunkp; 697typedef png_unknown_chunk * * png_unknown_chunkpp; 698#endif 699 700/* Flag values for the unknown chunk location byte. */ 701#define PNG_HAVE_IHDR 0x01 702#define PNG_HAVE_PLTE 0x02 703#define PNG_AFTER_IDAT 0x08 704 705/* Maximum positive integer used in PNG is (2^31)-1 */ 706#define PNG_UINT_31_MAX ((png_uint_32)0x7fffffffL) 707#define PNG_UINT_32_MAX ((png_uint_32)(-1)) 708#define PNG_SIZE_MAX ((png_size_t)(-1)) 709 710/* These are constants for fixed point values encoded in the 711 * PNG specification manner (x100000) 712 */ 713#define PNG_FP_1 100000 714#define PNG_FP_HALF 50000 715#define PNG_FP_MAX ((png_fixed_point)0x7fffffffL) 716#define PNG_FP_MIN (-PNG_FP_MAX) 717 718/* These describe the color_type field in png_info. */ 719/* color type masks */ 720#define PNG_COLOR_MASK_PALETTE 1 721#define PNG_COLOR_MASK_COLOR 2 722#define PNG_COLOR_MASK_ALPHA 4 723 724/* color types. Note that not all combinations are legal */ 725#define PNG_COLOR_TYPE_GRAY 0 726#define PNG_COLOR_TYPE_PALETTE (PNG_COLOR_MASK_COLOR | PNG_COLOR_MASK_PALETTE) 727#define PNG_COLOR_TYPE_RGB (PNG_COLOR_MASK_COLOR) 728#define PNG_COLOR_TYPE_RGB_ALPHA (PNG_COLOR_MASK_COLOR | PNG_COLOR_MASK_ALPHA) 729#define PNG_COLOR_TYPE_GRAY_ALPHA (PNG_COLOR_MASK_ALPHA) 730/* aliases */ 731#define PNG_COLOR_TYPE_RGBA PNG_COLOR_TYPE_RGB_ALPHA 732#define PNG_COLOR_TYPE_GA PNG_COLOR_TYPE_GRAY_ALPHA 733 734/* This is for compression type. PNG 1.0-1.2 only define the single type. */ 735#define PNG_COMPRESSION_TYPE_BASE 0 /* Deflate method 8, 32K window */ 736#define PNG_COMPRESSION_TYPE_DEFAULT PNG_COMPRESSION_TYPE_BASE 737 738/* This is for filter type. PNG 1.0-1.2 only define the single type. */ 739#define PNG_FILTER_TYPE_BASE 0 /* Single row per-byte filtering */ 740#define PNG_INTRAPIXEL_DIFFERENCING 64 /* Used only in MNG datastreams */ 741#define PNG_FILTER_TYPE_DEFAULT PNG_FILTER_TYPE_BASE 742 743/* These are for the interlacing type. These values should NOT be changed. */ 744#define PNG_INTERLACE_NONE 0 /* Non-interlaced image */ 745#define PNG_INTERLACE_ADAM7 1 /* Adam7 interlacing */ 746#define PNG_INTERLACE_LAST 2 /* Not a valid value */ 747 748/* These are for the oFFs chunk. These values should NOT be changed. */ 749#define PNG_OFFSET_PIXEL 0 /* Offset in pixels */ 750#define PNG_OFFSET_MICROMETER 1 /* Offset in micrometers (1/10^6 meter) */ 751#define PNG_OFFSET_LAST 2 /* Not a valid value */ 752 753/* These are for the pCAL chunk. These values should NOT be changed. */ 754#define PNG_EQUATION_LINEAR 0 /* Linear transformation */ 755#define PNG_EQUATION_BASE_E 1 /* Exponential base e transform */ 756#define PNG_EQUATION_ARBITRARY 2 /* Arbitrary base exponential transform */ 757#define PNG_EQUATION_HYPERBOLIC 3 /* Hyperbolic sine transformation */ 758#define PNG_EQUATION_LAST 4 /* Not a valid value */ 759 760/* These are for the sCAL chunk. These values should NOT be changed. */ 761#define PNG_SCALE_UNKNOWN 0 /* unknown unit (image scale) */ 762#define PNG_SCALE_METER 1 /* meters per pixel */ 763#define PNG_SCALE_RADIAN 2 /* radians per pixel */ 764#define PNG_SCALE_LAST 3 /* Not a valid value */ 765 766/* These are for the pHYs chunk. These values should NOT be changed. */ 767#define PNG_RESOLUTION_UNKNOWN 0 /* pixels/unknown unit (aspect ratio) */ 768#define PNG_RESOLUTION_METER 1 /* pixels/meter */ 769#define PNG_RESOLUTION_LAST 2 /* Not a valid value */ 770 771/* These are for the sRGB chunk. These values should NOT be changed. */ 772#define PNG_sRGB_INTENT_PERCEPTUAL 0 773#define PNG_sRGB_INTENT_RELATIVE 1 774#define PNG_sRGB_INTENT_SATURATION 2 775#define PNG_sRGB_INTENT_ABSOLUTE 3 776#define PNG_sRGB_INTENT_LAST 4 /* Not a valid value */ 777 778/* This is for text chunks */ 779#define PNG_KEYWORD_MAX_LENGTH 79 780 781/* Maximum number of entries in PLTE/sPLT/tRNS arrays */ 782#define PNG_MAX_PALETTE_LENGTH 256 783 784/* These determine if an ancillary chunk's data has been successfully read 785 * from the PNG header, or if the application has filled in the corresponding 786 * data in the info_struct to be written into the output file. The values 787 * of the PNG_INFO_<chunk> defines should NOT be changed. 788 */ 789#define PNG_INFO_gAMA 0x0001U 790#define PNG_INFO_sBIT 0x0002U 791#define PNG_INFO_cHRM 0x0004U 792#define PNG_INFO_PLTE 0x0008U 793#define PNG_INFO_tRNS 0x0010U 794#define PNG_INFO_bKGD 0x0020U 795#define PNG_INFO_hIST 0x0040U 796#define PNG_INFO_pHYs 0x0080U 797#define PNG_INFO_oFFs 0x0100U 798#define PNG_INFO_tIME 0x0200U 799#define PNG_INFO_pCAL 0x0400U 800#define PNG_INFO_sRGB 0x0800U /* GR-P, 0.96a */ 801#define PNG_INFO_iCCP 0x1000U /* ESR, 1.0.6 */ 802#define PNG_INFO_sPLT 0x2000U /* ESR, 1.0.6 */ 803#define PNG_INFO_sCAL 0x4000U /* ESR, 1.0.6 */ 804#define PNG_INFO_IDAT 0x8000U /* ESR, 1.0.6 */ 805 806/* This is used for the transformation routines, as some of them 807 * change these values for the row. It also should enable using 808 * the routines for other purposes. 809 */ 810typedef struct png_row_info_struct 811{ 812 png_uint_32 width; /* width of row */ 813 png_size_t rowbytes; /* number of bytes in row */ 814 png_byte color_type; /* color type of row */ 815 png_byte bit_depth; /* bit depth of row */ 816 png_byte channels; /* number of channels (1, 2, 3, or 4) */ 817 png_byte pixel_depth; /* bits per pixel (depth * channels) */ 818} png_row_info; 819 820typedef png_row_info * png_row_infop; 821typedef png_row_info * * png_row_infopp; 822 823/* These are the function types for the I/O functions and for the functions 824 * that allow the user to override the default I/O functions with his or her 825 * own. The png_error_ptr type should match that of user-supplied warning 826 * and error functions, while the png_rw_ptr type should match that of the 827 * user read/write data functions. Note that the 'write' function must not 828 * modify the buffer it is passed. The 'read' function, on the other hand, is 829 * expected to return the read data in the buffer. 830 */ 831typedef PNG_CALLBACK(void, *png_error_ptr, (png_structp, png_const_charp)); 832typedef PNG_CALLBACK(void, *png_rw_ptr, (png_structp, png_bytep, png_size_t)); 833typedef PNG_CALLBACK(void, *png_flush_ptr, (png_structp)); 834typedef PNG_CALLBACK(void, *png_read_status_ptr, (png_structp, png_uint_32, 835 int)); 836typedef PNG_CALLBACK(void, *png_write_status_ptr, (png_structp, png_uint_32, 837 int)); 838 839#ifdef PNG_PROGRESSIVE_READ_SUPPORTED 840typedef PNG_CALLBACK(void, *png_progressive_info_ptr, (png_structp, png_infop)); 841typedef PNG_CALLBACK(void, *png_progressive_end_ptr, (png_structp, png_infop)); 842 843/* The following callback receives png_uint_32 row_number, int pass for the 844 * png_bytep data of the row. When transforming an interlaced image the 845 * row number is the row number within the sub-image of the interlace pass, so 846 * the value will increase to the height of the sub-image (not the full image) 847 * then reset to 0 for the next pass. 848 * 849 * Use PNG_ROW_FROM_PASS_ROW(row, pass) and PNG_COL_FROM_PASS_COL(col, pass) to 850 * find the output pixel (x,y) given an interlaced sub-image pixel 851 * (row,col,pass). (See below for these macros.) 852 */ 853typedef PNG_CALLBACK(void, *png_progressive_row_ptr, (png_structp, png_bytep, 854 png_uint_32, int)); 855#endif 856 857#if defined(PNG_READ_USER_TRANSFORM_SUPPORTED) || \ 858 defined(PNG_WRITE_USER_TRANSFORM_SUPPORTED) 859typedef PNG_CALLBACK(void, *png_user_transform_ptr, (png_structp, png_row_infop, 860 png_bytep)); 861#endif 862 863#ifdef PNG_USER_CHUNKS_SUPPORTED 864typedef PNG_CALLBACK(int, *png_user_chunk_ptr, (png_structp, 865 png_unknown_chunkp)); 866#endif 867#ifdef PNG_UNKNOWN_CHUNKS_SUPPORTED 868/* not used anywhere */ 869/* typedef PNG_CALLBACK(void, *png_unknown_chunk_ptr, (png_structp)); */ 870#endif 871 872#ifdef PNG_SETJMP_SUPPORTED 873/* This must match the function definition in <setjmp.h>, and the application 874 * must include this before png.h to obtain the definition of jmp_buf. The 875 * function is required to be PNG_NORETURN, but this is not checked. If the 876 * function does return the application will crash via an abort() or similar 877 * system level call. 878 * 879 * If you get a warning here while building the library you may need to make 880 * changes to ensure that pnglibconf.h records the calling convention used by 881 * your compiler. This may be very difficult - try using a different compiler 882 * to build the library! 883 */ 884PNG_FUNCTION(void, (PNGCAPI *png_longjmp_ptr), PNGARG((jmp_buf, int)), typedef); 885#endif 886 887/* Transform masks for the high-level interface */ 888#define PNG_TRANSFORM_IDENTITY 0x0000 /* read and write */ 889#define PNG_TRANSFORM_STRIP_16 0x0001 /* read only */ 890#define PNG_TRANSFORM_STRIP_ALPHA 0x0002 /* read only */ 891#define PNG_TRANSFORM_PACKING 0x0004 /* read and write */ 892#define PNG_TRANSFORM_PACKSWAP 0x0008 /* read and write */ 893#define PNG_TRANSFORM_EXPAND 0x0010 /* read only */ 894#define PNG_TRANSFORM_INVERT_MONO 0x0020 /* read and write */ 895#define PNG_TRANSFORM_SHIFT 0x0040 /* read and write */ 896#define PNG_TRANSFORM_BGR 0x0080 /* read and write */ 897#define PNG_TRANSFORM_SWAP_ALPHA 0x0100 /* read and write */ 898#define PNG_TRANSFORM_SWAP_ENDIAN 0x0200 /* read and write */ 899#define PNG_TRANSFORM_INVERT_ALPHA 0x0400 /* read and write */ 900#define PNG_TRANSFORM_STRIP_FILLER 0x0800 /* write only */ 901/* Added to libpng-1.2.34 */ 902#define PNG_TRANSFORM_STRIP_FILLER_BEFORE PNG_TRANSFORM_STRIP_FILLER 903#define PNG_TRANSFORM_STRIP_FILLER_AFTER 0x1000 /* write only */ 904/* Added to libpng-1.4.0 */ 905#define PNG_TRANSFORM_GRAY_TO_RGB 0x2000 /* read only */ 906/* Added to libpng-1.5.4 */ 907#define PNG_TRANSFORM_EXPAND_16 0x4000 /* read only */ 908#if INT_MAX >= 0x8000 /* else this might break */ 909#define PNG_TRANSFORM_SCALE_16 0x8000 /* read only */ 910#endif 911 912/* Flags for MNG supported features */ 913#define PNG_FLAG_MNG_EMPTY_PLTE 0x01 914#define PNG_FLAG_MNG_FILTER_64 0x04 915#define PNG_ALL_MNG_FEATURES 0x05 916 917/* NOTE: prior to 1.5 these functions had no 'API' style declaration, 918 * this allowed the zlib default functions to be used on Windows 919 * platforms. In 1.5 the zlib default malloc (which just calls malloc and 920 * ignores the first argument) should be completely compatible with the 921 * following. 922 */ 923typedef PNG_CALLBACK(png_voidp, *png_malloc_ptr, (png_structp, 924 png_alloc_size_t)); 925typedef PNG_CALLBACK(void, *png_free_ptr, (png_structp, png_voidp)); 926 927/* Section 4: exported functions 928 * Here are the function definitions most commonly used. This is not 929 * the place to find out how to use libpng. See libpng-manual.txt for the 930 * full explanation, see example.c for the summary. This just provides 931 * a simple one line description of the use of each function. 932 * 933 * The PNG_EXPORT() and PNG_EXPORTA() macros used below are defined in 934 * pngconf.h and in the *.dfn files in the scripts directory. 935 * 936 * PNG_EXPORT(ordinal, type, name, (args)); 937 * 938 * ordinal: ordinal that is used while building 939 * *.def files. The ordinal value is only 940 * relevant when preprocessing png.h with 941 * the *.dfn files for building symbol table 942 * entries, and are removed by pngconf.h. 943 * type: return type of the function 944 * name: function name 945 * args: function arguments, with types 946 * 947 * When we wish to append attributes to a function prototype we use 948 * the PNG_EXPORTA() macro instead. 949 * 950 * PNG_EXPORTA(ordinal, type, name, (args), attributes); 951 * 952 * ordinal, type, name, and args: same as in PNG_EXPORT(). 953 * attributes: function attributes 954 */ 955 956/* Returns the version number of the library */ 957PNG_EXPORT(1, png_uint_32, png_access_version_number, (void)); 958 959/* Tell lib we have already handled the first <num_bytes> magic bytes. 960 * Handling more than 8 bytes from the beginning of the file is an error. 961 */ 962PNG_EXPORT(2, void, png_set_sig_bytes, (png_structrp png_ptr, int num_bytes)); 963 964/* Check sig[start] through sig[start + num_to_check - 1] to see if it's a 965 * PNG file. Returns zero if the supplied bytes match the 8-byte PNG 966 * signature, and non-zero otherwise. Having num_to_check == 0 or 967 * start > 7 will always fail (ie return non-zero). 968 */ 969PNG_EXPORT(3, int, png_sig_cmp, (png_const_bytep sig, png_size_t start, 970 png_size_t num_to_check)); 971 972/* Simple signature checking function. This is the same as calling 973 * png_check_sig(sig, n) := !png_sig_cmp(sig, 0, n). 974 */ 975#define png_check_sig(sig, n) !png_sig_cmp((sig), 0, (n)) 976 977/* Allocate and initialize png_ptr struct for reading, and any other memory. */ 978PNG_EXPORTA(4, png_structp, png_create_read_struct, 979 (png_const_charp user_png_ver, png_voidp error_ptr, 980 png_error_ptr error_fn, png_error_ptr warn_fn), 981 PNG_ALLOCATED); 982 983/* Allocate and initialize png_ptr struct for writing, and any other memory */ 984PNG_EXPORTA(5, png_structp, png_create_write_struct, 985 (png_const_charp user_png_ver, png_voidp error_ptr, png_error_ptr error_fn, 986 png_error_ptr warn_fn), 987 PNG_ALLOCATED); 988 989PNG_EXPORT(6, png_size_t, png_get_compression_buffer_size, 990 (png_const_structrp png_ptr)); 991 992PNG_EXPORT(7, void, png_set_compression_buffer_size, (png_structrp png_ptr, 993 png_size_t size)); 994 995/* Moved from pngconf.h in 1.4.0 and modified to ensure setjmp/longjmp 996 * match up. 997 */ 998#ifdef PNG_SETJMP_SUPPORTED 999/* This function returns the jmp_buf built in to *png_ptr. It must be 1000 * supplied with an appropriate 'longjmp' function to use on that jmp_buf 1001 * unless the default error function is overridden in which case NULL is 1002 * acceptable. The size of the jmp_buf is checked against the actual size 1003 * allocated by the library - the call will return NULL on a mismatch 1004 * indicating an ABI mismatch. 1005 */ 1006PNG_EXPORT(8, jmp_buf*, png_set_longjmp_fn, (png_structrp png_ptr, 1007 png_longjmp_ptr longjmp_fn, size_t jmp_buf_size)); 1008# define png_jmpbuf(png_ptr) \ 1009 (*png_set_longjmp_fn((png_ptr), longjmp, (sizeof (jmp_buf)))) 1010#else 1011# define png_jmpbuf(png_ptr) \ 1012 (LIBPNG_WAS_COMPILED_WITH__PNG_NO_SETJMP) 1013#endif 1014/* This function should be used by libpng applications in place of 1015 * longjmp(png_ptr->jmpbuf, val). If longjmp_fn() has been set, it 1016 * will use it; otherwise it will call PNG_ABORT(). This function was 1017 * added in libpng-1.5.0. 1018 */ 1019PNG_EXPORTA(9, void, png_longjmp, (png_const_structrp png_ptr, int val), 1020 PNG_NORETURN); 1021 1022#ifdef PNG_READ_SUPPORTED 1023/* Reset the compression stream */ 1024PNG_EXPORTA(10, int, png_reset_zstream, (png_structrp png_ptr), PNG_DEPRECATED); 1025#endif 1026 1027/* New functions added in libpng-1.0.2 (not enabled by default until 1.2.0) */ 1028#ifdef PNG_USER_MEM_SUPPORTED 1029PNG_EXPORTA(11, png_structp, png_create_read_struct_2, 1030 (png_const_charp user_png_ver, png_voidp error_ptr, png_error_ptr error_fn, 1031 png_error_ptr warn_fn, 1032 png_voidp mem_ptr, png_malloc_ptr malloc_fn, png_free_ptr free_fn), 1033 PNG_ALLOCATED); 1034PNG_EXPORTA(12, png_structp, png_create_write_struct_2, 1035 (png_const_charp user_png_ver, png_voidp error_ptr, png_error_ptr error_fn, 1036 png_error_ptr warn_fn, 1037 png_voidp mem_ptr, png_malloc_ptr malloc_fn, png_free_ptr free_fn), 1038 PNG_ALLOCATED); 1039#endif 1040 1041/* Write the PNG file signature. */ 1042PNG_EXPORT(13, void, png_write_sig, (png_structrp png_ptr)); 1043 1044/* Write a PNG chunk - size, type, (optional) data, CRC. */ 1045PNG_EXPORT(14, void, png_write_chunk, (png_structrp png_ptr, png_const_bytep 1046 chunk_name, png_const_bytep data, png_size_t length)); 1047 1048/* Write the start of a PNG chunk - length and chunk name. */ 1049PNG_EXPORT(15, void, png_write_chunk_start, (png_structrp png_ptr, 1050 png_const_bytep chunk_name, png_uint_32 length)); 1051 1052/* Write the data of a PNG chunk started with png_write_chunk_start(). */ 1053PNG_EXPORT(16, void, png_write_chunk_data, (png_structrp png_ptr, 1054 png_const_bytep data, png_size_t length)); 1055 1056/* Finish a chunk started with png_write_chunk_start() (includes CRC). */ 1057PNG_EXPORT(17, void, png_write_chunk_end, (png_structrp png_ptr)); 1058 1059/* Allocate and initialize the info structure */ 1060PNG_EXPORTA(18, png_infop, png_create_info_struct, (png_const_structrp png_ptr), 1061 PNG_ALLOCATED); 1062 1063/* DEPRECATED: this function allowed init structures to be created using the 1064 * default allocation method (typically malloc). Use is deprecated in 1.6.0 and 1065 * the API will be removed in the future. 1066 */ 1067PNG_EXPORTA(19, void, png_info_init_3, (png_infopp info_ptr, 1068 png_size_t png_info_struct_size), PNG_DEPRECATED); 1069 1070/* Writes all the PNG information before the image. */ 1071PNG_EXPORT(20, void, png_write_info_before_PLTE, 1072 (png_structrp png_ptr, png_const_inforp info_ptr)); 1073PNG_EXPORT(21, void, png_write_info, 1074 (png_structrp png_ptr, png_const_inforp info_ptr)); 1075 1076#ifdef PNG_SEQUENTIAL_READ_SUPPORTED 1077/* Read the information before the actual image data. */ 1078PNG_EXPORT(22, void, png_read_info, 1079 (png_structrp png_ptr, png_inforp info_ptr)); 1080#endif 1081 1082#ifdef PNG_TIME_RFC1123_SUPPORTED 1083 /* Convert to a US string format: there is no localization support in this 1084 * routine. The original implementation used a 29 character buffer in 1085 * png_struct, this will be removed in future versions. 1086 */ 1087#if PNG_LIBPNG_VER < 10700 1088/* To do: remove this from libpng17 (and from libpng17/png.c and pngstruct.h) */ 1089PNG_EXPORTA(23, png_const_charp, png_convert_to_rfc1123, (png_structrp png_ptr, 1090 png_const_timep ptime),PNG_DEPRECATED); 1091#endif 1092PNG_EXPORT(241, int, png_convert_to_rfc1123_buffer, (char out[29], 1093 png_const_timep ptime)); 1094#endif 1095 1096#ifdef PNG_CONVERT_tIME_SUPPORTED 1097/* Convert from a struct tm to png_time */ 1098PNG_EXPORT(24, void, png_convert_from_struct_tm, (png_timep ptime, 1099 const struct tm * ttime)); 1100 1101/* Convert from time_t to png_time. Uses gmtime() */ 1102PNG_EXPORT(25, void, png_convert_from_time_t, (png_timep ptime, time_t ttime)); 1103#endif /* CONVERT_tIME */ 1104 1105#ifdef PNG_READ_EXPAND_SUPPORTED 1106/* Expand data to 24-bit RGB, or 8-bit grayscale, with alpha if available. */ 1107PNG_EXPORT(26, void, png_set_expand, (png_structrp png_ptr)); 1108PNG_EXPORT(27, void, png_set_expand_gray_1_2_4_to_8, (png_structrp png_ptr)); 1109PNG_EXPORT(28, void, png_set_palette_to_rgb, (png_structrp png_ptr)); 1110PNG_EXPORT(29, void, png_set_tRNS_to_alpha, (png_structrp png_ptr)); 1111#endif 1112 1113#ifdef PNG_READ_EXPAND_16_SUPPORTED 1114/* Expand to 16-bit channels, forces conversion of palette to RGB and expansion 1115 * of a tRNS chunk if present. 1116 */ 1117PNG_EXPORT(221, void, png_set_expand_16, (png_structrp png_ptr)); 1118#endif 1119 1120#if defined(PNG_READ_BGR_SUPPORTED) || defined(PNG_WRITE_BGR_SUPPORTED) 1121/* Use blue, green, red order for pixels. */ 1122PNG_EXPORT(30, void, png_set_bgr, (png_structrp png_ptr)); 1123#endif 1124 1125#ifdef PNG_READ_GRAY_TO_RGB_SUPPORTED 1126/* Expand the grayscale to 24-bit RGB if necessary. */ 1127PNG_EXPORT(31, void, png_set_gray_to_rgb, (png_structrp png_ptr)); 1128#endif 1129 1130#ifdef PNG_READ_RGB_TO_GRAY_SUPPORTED 1131/* Reduce RGB to grayscale. */ 1132#define PNG_ERROR_ACTION_NONE 1 1133#define PNG_ERROR_ACTION_WARN 2 1134#define PNG_ERROR_ACTION_ERROR 3 1135#define PNG_RGB_TO_GRAY_DEFAULT (-1)/*for red/green coefficients*/ 1136 1137PNG_FP_EXPORT(32, void, png_set_rgb_to_gray, (png_structrp png_ptr, 1138 int error_action, double red, double green)) 1139PNG_FIXED_EXPORT(33, void, png_set_rgb_to_gray_fixed, (png_structrp png_ptr, 1140 int error_action, png_fixed_point red, png_fixed_point green)) 1141 1142PNG_EXPORT(34, png_byte, png_get_rgb_to_gray_status, (png_const_structrp 1143 png_ptr)); 1144#endif 1145 1146#ifdef PNG_BUILD_GRAYSCALE_PALETTE_SUPPORTED 1147PNG_EXPORT(35, void, png_build_grayscale_palette, (int bit_depth, 1148 png_colorp palette)); 1149#endif 1150 1151#ifdef PNG_READ_ALPHA_MODE_SUPPORTED 1152/* How the alpha channel is interpreted - this affects how the color channels 1153 * of a PNG file are returned to the calling application when an alpha channel, 1154 * or a tRNS chunk in a palette file, is present. 1155 * 1156 * This has no effect on the way pixels are written into a PNG output 1157 * datastream. The color samples in a PNG datastream are never premultiplied 1158 * with the alpha samples. 1159 * 1160 * The default is to return data according to the PNG specification: the alpha 1161 * channel is a linear measure of the contribution of the pixel to the 1162 * corresponding composited pixel, and the color channels are unassociated 1163 * (not premultiplied). The gamma encoded color channels must be scaled 1164 * according to the contribution and to do this it is necessary to undo 1165 * the encoding, scale the color values, perform the composition and reencode 1166 * the values. This is the 'PNG' mode. 1167 * 1168 * The alternative is to 'associate' the alpha with the color information by 1169 * storing color channel values that have been scaled by the alpha. 1170 * image. These are the 'STANDARD', 'ASSOCIATED' or 'PREMULTIPLIED' modes 1171 * (the latter being the two common names for associated alpha color channels). 1172 * 1173 * For the 'OPTIMIZED' mode, a pixel is treated as opaque only if the alpha 1174 * value is equal to the maximum value. 1175 * 1176 * The final choice is to gamma encode the alpha channel as well. This is 1177 * broken because, in practice, no implementation that uses this choice 1178 * correctly undoes the encoding before handling alpha composition. Use this 1179 * choice only if other serious errors in the software or hardware you use 1180 * mandate it; the typical serious error is for dark halos to appear around 1181 * opaque areas of the composited PNG image because of arithmetic overflow. 1182 * 1183 * The API function png_set_alpha_mode specifies which of these choices to use 1184 * with an enumerated 'mode' value and the gamma of the required output: 1185 */ 1186#define PNG_ALPHA_PNG 0 /* according to the PNG standard */ 1187#define PNG_ALPHA_STANDARD 1 /* according to Porter/Duff */ 1188#define PNG_ALPHA_ASSOCIATED 1 /* as above; this is the normal practice */ 1189#define PNG_ALPHA_PREMULTIPLIED 1 /* as above */ 1190#define PNG_ALPHA_OPTIMIZED 2 /* 'PNG' for opaque pixels, else 'STANDARD' */ 1191#define PNG_ALPHA_BROKEN 3 /* the alpha channel is gamma encoded */ 1192 1193PNG_FP_EXPORT(227, void, png_set_alpha_mode, (png_structrp png_ptr, int mode, 1194 double output_gamma)) 1195PNG_FIXED_EXPORT(228, void, png_set_alpha_mode_fixed, (png_structrp png_ptr, 1196 int mode, png_fixed_point output_gamma)) 1197#endif 1198 1199#if defined(PNG_GAMMA_SUPPORTED) || defined(PNG_READ_ALPHA_MODE_SUPPORTED) 1200/* The output_gamma value is a screen gamma in libpng terminology: it expresses 1201 * how to decode the output values, not how they are encoded. 1202 */ 1203#define PNG_DEFAULT_sRGB -1 /* sRGB gamma and color space */ 1204#define PNG_GAMMA_MAC_18 -2 /* Old Mac '1.8' gamma and color space */ 1205#define PNG_GAMMA_sRGB 220000 /* Television standards--matches sRGB gamma */ 1206#define PNG_GAMMA_LINEAR PNG_FP_1 /* Linear */ 1207#endif 1208 1209/* The following are examples of calls to png_set_alpha_mode to achieve the 1210 * required overall gamma correction and, where necessary, alpha 1211 * premultiplication. 1212 * 1213 * png_set_alpha_mode(pp, PNG_ALPHA_PNG, PNG_DEFAULT_sRGB); 1214 * This is the default libpng handling of the alpha channel - it is not 1215 * pre-multiplied into the color components. In addition the call states 1216 * that the output is for a sRGB system and causes all PNG files without gAMA 1217 * chunks to be assumed to be encoded using sRGB. 1218 * 1219 * png_set_alpha_mode(pp, PNG_ALPHA_PNG, PNG_GAMMA_MAC); 1220 * In this case the output is assumed to be something like an sRGB conformant 1221 * display preceeded by a power-law lookup table of power 1.45. This is how 1222 * early Mac systems behaved. 1223 * 1224 * png_set_alpha_mode(pp, PNG_ALPHA_STANDARD, PNG_GAMMA_LINEAR); 1225 * This is the classic Jim Blinn approach and will work in academic 1226 * environments where everything is done by the book. It has the shortcoming 1227 * of assuming that input PNG data with no gamma information is linear - this 1228 * is unlikely to be correct unless the PNG files where generated locally. 1229 * Most of the time the output precision will be so low as to show 1230 * significant banding in dark areas of the image. 1231 * 1232 * png_set_expand_16(pp); 1233 * png_set_alpha_mode(pp, PNG_ALPHA_STANDARD, PNG_DEFAULT_sRGB); 1234 * This is a somewhat more realistic Jim Blinn inspired approach. PNG files 1235 * are assumed to have the sRGB encoding if not marked with a gamma value and 1236 * the output is always 16 bits per component. This permits accurate scaling 1237 * and processing of the data. If you know that your input PNG files were 1238 * generated locally you might need to replace PNG_DEFAULT_sRGB with the 1239 * correct value for your system. 1240 * 1241 * png_set_alpha_mode(pp, PNG_ALPHA_OPTIMIZED, PNG_DEFAULT_sRGB); 1242 * If you just need to composite the PNG image onto an existing background 1243 * and if you control the code that does this you can use the optimization 1244 * setting. In this case you just copy completely opaque pixels to the 1245 * output. For pixels that are not completely transparent (you just skip 1246 * those) you do the composition math using png_composite or png_composite_16 1247 * below then encode the resultant 8-bit or 16-bit values to match the output 1248 * encoding. 1249 * 1250 * Other cases 1251 * If neither the PNG nor the standard linear encoding work for you because 1252 * of the software or hardware you use then you have a big problem. The PNG 1253 * case will probably result in halos around the image. The linear encoding 1254 * will probably result in a washed out, too bright, image (it's actually too 1255 * contrasty.) Try the ALPHA_OPTIMIZED mode above - this will probably 1256 * substantially reduce the halos. Alternatively try: 1257 * 1258 * png_set_alpha_mode(pp, PNG_ALPHA_BROKEN, PNG_DEFAULT_sRGB); 1259 * This option will also reduce the halos, but there will be slight dark 1260 * halos round the opaque parts of the image where the background is light. 1261 * In the OPTIMIZED mode the halos will be light halos where the background 1262 * is dark. Take your pick - the halos are unavoidable unless you can get 1263 * your hardware/software fixed! (The OPTIMIZED approach is slightly 1264 * faster.) 1265 * 1266 * When the default gamma of PNG files doesn't match the output gamma. 1267 * If you have PNG files with no gamma information png_set_alpha_mode allows 1268 * you to provide a default gamma, but it also sets the ouput gamma to the 1269 * matching value. If you know your PNG files have a gamma that doesn't 1270 * match the output you can take advantage of the fact that 1271 * png_set_alpha_mode always sets the output gamma but only sets the PNG 1272 * default if it is not already set: 1273 * 1274 * png_set_alpha_mode(pp, PNG_ALPHA_PNG, PNG_DEFAULT_sRGB); 1275 * png_set_alpha_mode(pp, PNG_ALPHA_PNG, PNG_GAMMA_MAC); 1276 * The first call sets both the default and the output gamma values, the 1277 * second call overrides the output gamma without changing the default. This 1278 * is easier than achieving the same effect with png_set_gamma. You must use 1279 * PNG_ALPHA_PNG for the first call - internal checking in png_set_alpha will 1280 * fire if more than one call to png_set_alpha_mode and png_set_background is 1281 * made in the same read operation, however multiple calls with PNG_ALPHA_PNG 1282 * are ignored. 1283 */ 1284 1285#ifdef PNG_READ_STRIP_ALPHA_SUPPORTED 1286PNG_EXPORT(36, void, png_set_strip_alpha, (png_structrp png_ptr)); 1287#endif 1288 1289#if defined(PNG_READ_SWAP_ALPHA_SUPPORTED) || \ 1290 defined(PNG_WRITE_SWAP_ALPHA_SUPPORTED) 1291PNG_EXPORT(37, void, png_set_swap_alpha, (png_structrp png_ptr)); 1292#endif 1293 1294#if defined(PNG_READ_INVERT_ALPHA_SUPPORTED) || \ 1295 defined(PNG_WRITE_INVERT_ALPHA_SUPPORTED) 1296PNG_EXPORT(38, void, png_set_invert_alpha, (png_structrp png_ptr)); 1297#endif 1298 1299#if defined(PNG_READ_FILLER_SUPPORTED) || defined(PNG_WRITE_FILLER_SUPPORTED) 1300/* Add a filler byte to 8-bit or 16-bit Gray or 24-bit or 48-bit RGB images. */ 1301PNG_EXPORT(39, void, png_set_filler, (png_structrp png_ptr, png_uint_32 filler, 1302 int flags)); 1303/* The values of the PNG_FILLER_ defines should NOT be changed */ 1304# define PNG_FILLER_BEFORE 0 1305# define PNG_FILLER_AFTER 1 1306/* Add an alpha byte to 8-bit or 16-bit Gray or 24-bit or 48-bit RGB images. */ 1307PNG_EXPORT(40, void, png_set_add_alpha, (png_structrp png_ptr, 1308 png_uint_32 filler, int flags)); 1309#endif /* READ_FILLER || WRITE_FILLER */ 1310 1311#if defined(PNG_READ_SWAP_SUPPORTED) || defined(PNG_WRITE_SWAP_SUPPORTED) 1312/* Swap bytes in 16-bit depth files. */ 1313PNG_EXPORT(41, void, png_set_swap, (png_structrp png_ptr)); 1314#endif 1315 1316#if defined(PNG_READ_PACK_SUPPORTED) || defined(PNG_WRITE_PACK_SUPPORTED) 1317/* Use 1 byte per pixel in 1, 2, or 4-bit depth files. */ 1318PNG_EXPORT(42, void, png_set_packing, (png_structrp png_ptr)); 1319#endif 1320 1321#if defined(PNG_READ_PACKSWAP_SUPPORTED) || \ 1322 defined(PNG_WRITE_PACKSWAP_SUPPORTED) 1323/* Swap packing order of pixels in bytes. */ 1324PNG_EXPORT(43, void, png_set_packswap, (png_structrp png_ptr)); 1325#endif 1326 1327#if defined(PNG_READ_SHIFT_SUPPORTED) || defined(PNG_WRITE_SHIFT_SUPPORTED) 1328/* Converts files to legal bit depths. */ 1329PNG_EXPORT(44, void, png_set_shift, (png_structrp png_ptr, png_const_color_8p 1330 true_bits)); 1331#endif 1332 1333#if defined(PNG_READ_INTERLACING_SUPPORTED) || \ 1334 defined(PNG_WRITE_INTERLACING_SUPPORTED) 1335/* Have the code handle the interlacing. Returns the number of passes. 1336 * MUST be called before png_read_update_info or png_start_read_image, 1337 * otherwise it will not have the desired effect. Note that it is still 1338 * necessary to call png_read_row or png_read_rows png_get_image_height 1339 * times for each pass. 1340*/ 1341PNG_EXPORT(45, int, png_set_interlace_handling, (png_structrp png_ptr)); 1342#endif 1343 1344#if defined(PNG_READ_INVERT_SUPPORTED) || defined(PNG_WRITE_INVERT_SUPPORTED) 1345/* Invert monochrome files */ 1346PNG_EXPORT(46, void, png_set_invert_mono, (png_structrp png_ptr)); 1347#endif 1348 1349#ifdef PNG_READ_BACKGROUND_SUPPORTED 1350/* Handle alpha and tRNS by replacing with a background color. Prior to 1351 * libpng-1.5.4 this API must not be called before the PNG file header has been 1352 * read. Doing so will result in unexpected behavior and possible warnings or 1353 * errors if the PNG file contains a bKGD chunk. 1354 */ 1355PNG_FP_EXPORT(47, void, png_set_background, (png_structrp png_ptr, 1356 png_const_color_16p background_color, int background_gamma_code, 1357 int need_expand, double background_gamma)) 1358PNG_FIXED_EXPORT(215, void, png_set_background_fixed, (png_structrp png_ptr, 1359 png_const_color_16p background_color, int background_gamma_code, 1360 int need_expand, png_fixed_point background_gamma)) 1361#endif 1362#ifdef PNG_READ_BACKGROUND_SUPPORTED 1363# define PNG_BACKGROUND_GAMMA_UNKNOWN 0 1364# define PNG_BACKGROUND_GAMMA_SCREEN 1 1365# define PNG_BACKGROUND_GAMMA_FILE 2 1366# define PNG_BACKGROUND_GAMMA_UNIQUE 3 1367#endif 1368 1369#ifdef PNG_READ_SCALE_16_TO_8_SUPPORTED 1370/* Scale a 16-bit depth file down to 8-bit, accurately. */ 1371PNG_EXPORT(229, void, png_set_scale_16, (png_structrp png_ptr)); 1372#endif 1373 1374#ifdef PNG_READ_STRIP_16_TO_8_SUPPORTED 1375#define PNG_READ_16_TO_8_SUPPORTED /* Name prior to 1.5.4 */ 1376/* Strip the second byte of information from a 16-bit depth file. */ 1377PNG_EXPORT(48, void, png_set_strip_16, (png_structrp png_ptr)); 1378#endif 1379 1380#ifdef PNG_READ_QUANTIZE_SUPPORTED 1381/* Turn on quantizing, and reduce the palette to the number of colors 1382 * available. 1383 */ 1384PNG_EXPORT(49, void, png_set_quantize, (png_structrp png_ptr, 1385 png_colorp palette, int num_palette, int maximum_colors, 1386 png_const_uint_16p histogram, int full_quantize)); 1387#endif 1388 1389#ifdef PNG_READ_GAMMA_SUPPORTED 1390/* The threshold on gamma processing is configurable but hard-wired into the 1391 * library. The following is the floating point variant. 1392 */ 1393#define PNG_GAMMA_THRESHOLD (PNG_GAMMA_THRESHOLD_FIXED*.00001) 1394 1395/* Handle gamma correction. Screen_gamma=(display_exponent). 1396 * NOTE: this API simply sets the screen and file gamma values. It will 1397 * therefore override the value for gamma in a PNG file if it is called after 1398 * the file header has been read - use with care - call before reading the PNG 1399 * file for best results! 1400 * 1401 * These routines accept the same gamma values as png_set_alpha_mode (described 1402 * above). The PNG_GAMMA_ defines and PNG_DEFAULT_sRGB can be passed to either 1403 * API (floating point or fixed.) Notice, however, that the 'file_gamma' value 1404 * is the inverse of a 'screen gamma' value. 1405 */ 1406PNG_FP_EXPORT(50, void, png_set_gamma, (png_structrp png_ptr, 1407 double screen_gamma, double override_file_gamma)) 1408PNG_FIXED_EXPORT(208, void, png_set_gamma_fixed, (png_structrp png_ptr, 1409 png_fixed_point screen_gamma, png_fixed_point override_file_gamma)) 1410#endif 1411 1412#ifdef PNG_WRITE_FLUSH_SUPPORTED 1413/* Set how many lines between output flushes - 0 for no flushing */ 1414PNG_EXPORT(51, void, png_set_flush, (png_structrp png_ptr, int nrows)); 1415/* Flush the current PNG output buffer */ 1416PNG_EXPORT(52, void, png_write_flush, (png_structrp png_ptr)); 1417#endif 1418 1419/* Optional update palette with requested transformations */ 1420PNG_EXPORT(53, void, png_start_read_image, (png_structrp png_ptr)); 1421 1422/* Optional call to update the users info structure */ 1423PNG_EXPORT(54, void, png_read_update_info, (png_structrp png_ptr, 1424 png_inforp info_ptr)); 1425 1426#ifdef PNG_SEQUENTIAL_READ_SUPPORTED 1427/* Read one or more rows of image data. */ 1428PNG_EXPORT(55, void, png_read_rows, (png_structrp png_ptr, png_bytepp row, 1429 png_bytepp display_row, png_uint_32 num_rows)); 1430#endif 1431 1432#ifdef PNG_SEQUENTIAL_READ_SUPPORTED 1433/* Read a row of data. */ 1434PNG_EXPORT(56, void, png_read_row, (png_structrp png_ptr, png_bytep row, 1435 png_bytep display_row)); 1436#endif 1437 1438#ifdef PNG_SEQUENTIAL_READ_SUPPORTED 1439/* Read the whole image into memory at once. */ 1440PNG_EXPORT(57, void, png_read_image, (png_structrp png_ptr, png_bytepp image)); 1441#endif 1442 1443/* Write a row of image data */ 1444PNG_EXPORT(58, void, png_write_row, (png_structrp png_ptr, 1445 png_const_bytep row)); 1446 1447/* Write a few rows of image data: (*row) is not written; however, the type 1448 * is declared as writeable to maintain compatibility with previous versions 1449 * of libpng and to allow the 'display_row' array from read_rows to be passed 1450 * unchanged to write_rows. 1451 */ 1452PNG_EXPORT(59, void, png_write_rows, (png_structrp png_ptr, png_bytepp row, 1453 png_uint_32 num_rows)); 1454 1455/* Write the image data */ 1456PNG_EXPORT(60, void, png_write_image, (png_structrp png_ptr, png_bytepp image)); 1457 1458/* Write the end of the PNG file. */ 1459PNG_EXPORT(61, void, png_write_end, (png_structrp png_ptr, 1460 png_inforp info_ptr)); 1461 1462#ifdef PNG_SEQUENTIAL_READ_SUPPORTED 1463/* Read the end of the PNG file. */ 1464PNG_EXPORT(62, void, png_read_end, (png_structrp png_ptr, png_inforp info_ptr)); 1465#endif 1466 1467/* Free any memory associated with the png_info_struct */ 1468PNG_EXPORT(63, void, png_destroy_info_struct, (png_const_structrp png_ptr, 1469 png_infopp info_ptr_ptr)); 1470 1471/* Free any memory associated with the png_struct and the png_info_structs */ 1472PNG_EXPORT(64, void, png_destroy_read_struct, (png_structpp png_ptr_ptr, 1473 png_infopp info_ptr_ptr, png_infopp end_info_ptr_ptr)); 1474 1475/* Free any memory associated with the png_struct and the png_info_structs */ 1476PNG_EXPORT(65, void, png_destroy_write_struct, (png_structpp png_ptr_ptr, 1477 png_infopp info_ptr_ptr)); 1478 1479/* Set the libpng method of handling chunk CRC errors */ 1480PNG_EXPORT(66, void, png_set_crc_action, (png_structrp png_ptr, int crit_action, 1481 int ancil_action)); 1482 1483/* Values for png_set_crc_action() say how to handle CRC errors in 1484 * ancillary and critical chunks, and whether to use the data contained 1485 * therein. Note that it is impossible to "discard" data in a critical 1486 * chunk. For versions prior to 0.90, the action was always error/quit, 1487 * whereas in version 0.90 and later, the action for CRC errors in ancillary 1488 * chunks is warn/discard. These values should NOT be changed. 1489 * 1490 * value action:critical action:ancillary 1491 */ 1492#define PNG_CRC_DEFAULT 0 /* error/quit warn/discard data */ 1493#define PNG_CRC_ERROR_QUIT 1 /* error/quit error/quit */ 1494#define PNG_CRC_WARN_DISCARD 2 /* (INVALID) warn/discard data */ 1495#define PNG_CRC_WARN_USE 3 /* warn/use data warn/use data */ 1496#define PNG_CRC_QUIET_USE 4 /* quiet/use data quiet/use data */ 1497#define PNG_CRC_NO_CHANGE 5 /* use current value use current value */ 1498 1499#ifdef PNG_WRITE_SUPPORTED 1500/* These functions give the user control over the scan-line filtering in 1501 * libpng and the compression methods used by zlib. These functions are 1502 * mainly useful for testing, as the defaults should work with most users. 1503 * Those users who are tight on memory or want faster performance at the 1504 * expense of compression can modify them. See the compression library 1505 * header file (zlib.h) for an explination of the compression functions. 1506 */ 1507 1508/* Set the filtering method(s) used by libpng. Currently, the only valid 1509 * value for "method" is 0. 1510 */ 1511PNG_EXPORT(67, void, png_set_filter, (png_structrp png_ptr, int method, 1512 int filters)); 1513#endif /* WRITE */ 1514 1515/* Flags for png_set_filter() to say which filters to use. The flags 1516 * are chosen so that they don't conflict with real filter types 1517 * below, in case they are supplied instead of the #defined constants. 1518 * These values should NOT be changed. 1519 */ 1520#define PNG_NO_FILTERS 0x00 1521#define PNG_FILTER_NONE 0x08 1522#define PNG_FILTER_SUB 0x10 1523#define PNG_FILTER_UP 0x20 1524#define PNG_FILTER_AVG 0x40 1525#define PNG_FILTER_PAETH 0x80 1526#define PNG_FAST_FILTERS (PNG_FILTER_NONE | PNG_FILTER_SUB | PNG_FILTER_UP) 1527#define PNG_ALL_FILTERS (PNG_FAST_FILTERS | PNG_FILTER_AVG | PNG_FILTER_PAETH) 1528 1529/* Filter values (not flags) - used in pngwrite.c, pngwutil.c for now. 1530 * These defines should NOT be changed. 1531 */ 1532#define PNG_FILTER_VALUE_NONE 0 1533#define PNG_FILTER_VALUE_SUB 1 1534#define PNG_FILTER_VALUE_UP 2 1535#define PNG_FILTER_VALUE_AVG 3 1536#define PNG_FILTER_VALUE_PAETH 4 1537#define PNG_FILTER_VALUE_LAST 5 1538 1539#ifdef PNG_WRITE_SUPPORTED 1540#ifdef PNG_WRITE_WEIGHTED_FILTER_SUPPORTED /* DEPRECATED */ 1541PNG_FP_EXPORT(68, void, png_set_filter_heuristics, (png_structrp png_ptr, 1542 int heuristic_method, int num_weights, png_const_doublep filter_weights, 1543 png_const_doublep filter_costs)) 1544PNG_FIXED_EXPORT(209, void, png_set_filter_heuristics_fixed, 1545 (png_structrp png_ptr, int heuristic_method, int num_weights, 1546 png_const_fixed_point_p filter_weights, 1547 png_const_fixed_point_p filter_costs)) 1548#endif /* WRITE_WEIGHTED_FILTER */ 1549 1550/* The following are no longer used and will be removed from libpng-1.7: */ 1551#define PNG_FILTER_HEURISTIC_DEFAULT 0 /* Currently "UNWEIGHTED" */ 1552#define PNG_FILTER_HEURISTIC_UNWEIGHTED 1 /* Used by libpng < 0.95 */ 1553#define PNG_FILTER_HEURISTIC_WEIGHTED 2 /* Experimental feature */ 1554#define PNG_FILTER_HEURISTIC_LAST 3 /* Not a valid value */ 1555 1556/* Set the library compression level. Currently, valid values range from 1557 * 0 - 9, corresponding directly to the zlib compression levels 0 - 9 1558 * (0 - no compression, 9 - "maximal" compression). Note that tests have 1559 * shown that zlib compression levels 3-6 usually perform as well as level 9 1560 * for PNG images, and do considerably fewer caclulations. In the future, 1561 * these values may not correspond directly to the zlib compression levels. 1562 */ 1563#ifdef PNG_WRITE_CUSTOMIZE_COMPRESSION_SUPPORTED 1564PNG_EXPORT(69, void, png_set_compression_level, (png_structrp png_ptr, 1565 int level)); 1566 1567PNG_EXPORT(70, void, png_set_compression_mem_level, (png_structrp png_ptr, 1568 int mem_level)); 1569 1570PNG_EXPORT(71, void, png_set_compression_strategy, (png_structrp png_ptr, 1571 int strategy)); 1572 1573/* If PNG_WRITE_OPTIMIZE_CMF_SUPPORTED is defined, libpng will use a 1574 * smaller value of window_bits if it can do so safely. 1575 */ 1576PNG_EXPORT(72, void, png_set_compression_window_bits, (png_structrp png_ptr, 1577 int window_bits)); 1578 1579PNG_EXPORT(73, void, png_set_compression_method, (png_structrp png_ptr, 1580 int method)); 1581#endif /* WRITE_CUSTOMIZE_COMPRESSION */ 1582 1583#ifdef PNG_WRITE_CUSTOMIZE_ZTXT_COMPRESSION_SUPPORTED 1584/* Also set zlib parameters for compressing non-IDAT chunks */ 1585PNG_EXPORT(222, void, png_set_text_compression_level, (png_structrp png_ptr, 1586 int level)); 1587 1588PNG_EXPORT(223, void, png_set_text_compression_mem_level, (png_structrp png_ptr, 1589 int mem_level)); 1590 1591PNG_EXPORT(224, void, png_set_text_compression_strategy, (png_structrp png_ptr, 1592 int strategy)); 1593 1594/* If PNG_WRITE_OPTIMIZE_CMF_SUPPORTED is defined, libpng will use a 1595 * smaller value of window_bits if it can do so safely. 1596 */ 1597PNG_EXPORT(225, void, png_set_text_compression_window_bits, 1598 (png_structrp png_ptr, int window_bits)); 1599 1600PNG_EXPORT(226, void, png_set_text_compression_method, (png_structrp png_ptr, 1601 int method)); 1602#endif /* WRITE_CUSTOMIZE_ZTXT_COMPRESSION */ 1603#endif /* WRITE */ 1604 1605/* These next functions are called for input/output, memory, and error 1606 * handling. They are in the file pngrio.c, pngwio.c, and pngerror.c, 1607 * and call standard C I/O routines such as fread(), fwrite(), and 1608 * fprintf(). These functions can be made to use other I/O routines 1609 * at run time for those applications that need to handle I/O in a 1610 * different manner by calling png_set_???_fn(). See libpng-manual.txt for 1611 * more information. 1612 */ 1613 1614#ifdef PNG_STDIO_SUPPORTED 1615/* Initialize the input/output for the PNG file to the default functions. */ 1616PNG_EXPORT(74, void, png_init_io, (png_structrp png_ptr, png_FILE_p fp)); 1617#endif 1618 1619/* Replace the (error and abort), and warning functions with user 1620 * supplied functions. If no messages are to be printed you must still 1621 * write and use replacement functions. The replacement error_fn should 1622 * still do a longjmp to the last setjmp location if you are using this 1623 * method of error handling. If error_fn or warning_fn is NULL, the 1624 * default function will be used. 1625 */ 1626 1627PNG_EXPORT(75, void, png_set_error_fn, (png_structrp png_ptr, 1628 png_voidp error_ptr, png_error_ptr error_fn, png_error_ptr warning_fn)); 1629 1630/* Return the user pointer associated with the error functions */ 1631PNG_EXPORT(76, png_voidp, png_get_error_ptr, (png_const_structrp png_ptr)); 1632 1633/* Replace the default data output functions with a user supplied one(s). 1634 * If buffered output is not used, then output_flush_fn can be set to NULL. 1635 * If PNG_WRITE_FLUSH_SUPPORTED is not defined at libpng compile time 1636 * output_flush_fn will be ignored (and thus can be NULL). 1637 * It is probably a mistake to use NULL for output_flush_fn if 1638 * write_data_fn is not also NULL unless you have built libpng with 1639 * PNG_WRITE_FLUSH_SUPPORTED undefined, because in this case libpng's 1640 * default flush function, which uses the standard *FILE structure, will 1641 * be used. 1642 */ 1643PNG_EXPORT(77, void, png_set_write_fn, (png_structrp png_ptr, png_voidp io_ptr, 1644 png_rw_ptr write_data_fn, png_flush_ptr output_flush_fn)); 1645 1646/* Replace the default data input function with a user supplied one. */ 1647PNG_EXPORT(78, void, png_set_read_fn, (png_structrp png_ptr, png_voidp io_ptr, 1648 png_rw_ptr read_data_fn)); 1649 1650/* Return the user pointer associated with the I/O functions */ 1651PNG_EXPORT(79, png_voidp, png_get_io_ptr, (png_const_structrp png_ptr)); 1652 1653PNG_EXPORT(80, void, png_set_read_status_fn, (png_structrp png_ptr, 1654 png_read_status_ptr read_row_fn)); 1655 1656PNG_EXPORT(81, void, png_set_write_status_fn, (png_structrp png_ptr, 1657 png_write_status_ptr write_row_fn)); 1658 1659#ifdef PNG_USER_MEM_SUPPORTED 1660/* Replace the default memory allocation functions with user supplied one(s). */ 1661PNG_EXPORT(82, void, png_set_mem_fn, (png_structrp png_ptr, png_voidp mem_ptr, 1662 png_malloc_ptr malloc_fn, png_free_ptr free_fn)); 1663/* Return the user pointer associated with the memory functions */ 1664PNG_EXPORT(83, png_voidp, png_get_mem_ptr, (png_const_structrp png_ptr)); 1665#endif 1666 1667#ifdef PNG_READ_USER_TRANSFORM_SUPPORTED 1668PNG_EXPORT(84, void, png_set_read_user_transform_fn, (png_structrp png_ptr, 1669 png_user_transform_ptr read_user_transform_fn)); 1670#endif 1671 1672#ifdef PNG_WRITE_USER_TRANSFORM_SUPPORTED 1673PNG_EXPORT(85, void, png_set_write_user_transform_fn, (png_structrp png_ptr, 1674 png_user_transform_ptr write_user_transform_fn)); 1675#endif 1676 1677#ifdef PNG_USER_TRANSFORM_PTR_SUPPORTED 1678PNG_EXPORT(86, void, png_set_user_transform_info, (png_structrp png_ptr, 1679 png_voidp user_transform_ptr, int user_transform_depth, 1680 int user_transform_channels)); 1681/* Return the user pointer associated with the user transform functions */ 1682PNG_EXPORT(87, png_voidp, png_get_user_transform_ptr, 1683 (png_const_structrp png_ptr)); 1684#endif 1685 1686#ifdef PNG_USER_TRANSFORM_INFO_SUPPORTED 1687/* Return information about the row currently being processed. Note that these 1688 * APIs do not fail but will return unexpected results if called outside a user 1689 * transform callback. Also note that when transforming an interlaced image the 1690 * row number is the row number within the sub-image of the interlace pass, so 1691 * the value will increase to the height of the sub-image (not the full image) 1692 * then reset to 0 for the next pass. 1693 * 1694 * Use PNG_ROW_FROM_PASS_ROW(row, pass) and PNG_COL_FROM_PASS_COL(col, pass) to 1695 * find the output pixel (x,y) given an interlaced sub-image pixel 1696 * (row,col,pass). (See below for these macros.) 1697 */ 1698PNG_EXPORT(217, png_uint_32, png_get_current_row_number, (png_const_structrp)); 1699PNG_EXPORT(218, png_byte, png_get_current_pass_number, (png_const_structrp)); 1700#endif 1701 1702#ifdef PNG_READ_USER_CHUNKS_SUPPORTED 1703/* This callback is called only for *unknown* chunks. If 1704 * PNG_HANDLE_AS_UNKNOWN_SUPPORTED is set then it is possible to set known 1705 * chunks to be treated as unknown, however in this case the callback must do 1706 * any processing required by the chunk (e.g. by calling the appropriate 1707 * png_set_ APIs.) 1708 * 1709 * There is no write support - on write, by default, all the chunks in the 1710 * 'unknown' list are written in the specified position. 1711 * 1712 * The integer return from the callback function is interpreted thus: 1713 * 1714 * negative: An error occurred; png_chunk_error will be called. 1715 * zero: The chunk was not handled, the chunk will be saved. A critical 1716 * chunk will cause an error at this point unless it is to be saved. 1717 * positive: The chunk was handled, libpng will ignore/discard it. 1718 * 1719 * See "INTERACTION WTIH USER CHUNK CALLBACKS" below for important notes about 1720 * how this behavior will change in libpng 1.7 1721 */ 1722PNG_EXPORT(88, void, png_set_read_user_chunk_fn, (png_structrp png_ptr, 1723 png_voidp user_chunk_ptr, png_user_chunk_ptr read_user_chunk_fn)); 1724#endif 1725 1726#ifdef PNG_USER_CHUNKS_SUPPORTED 1727PNG_EXPORT(89, png_voidp, png_get_user_chunk_ptr, (png_const_structrp png_ptr)); 1728#endif 1729 1730#ifdef PNG_PROGRESSIVE_READ_SUPPORTED 1731/* Sets the function callbacks for the push reader, and a pointer to a 1732 * user-defined structure available to the callback functions. 1733 */ 1734PNG_EXPORT(90, void, png_set_progressive_read_fn, (png_structrp png_ptr, 1735 png_voidp progressive_ptr, png_progressive_info_ptr info_fn, 1736 png_progressive_row_ptr row_fn, png_progressive_end_ptr end_fn)); 1737 1738/* Returns the user pointer associated with the push read functions */ 1739PNG_EXPORT(91, png_voidp, png_get_progressive_ptr, 1740 (png_const_structrp png_ptr)); 1741 1742/* Function to be called when data becomes available */ 1743PNG_EXPORT(92, void, png_process_data, (png_structrp png_ptr, 1744 png_inforp info_ptr, png_bytep buffer, png_size_t buffer_size)); 1745 1746/* A function which may be called *only* within png_process_data to stop the 1747 * processing of any more data. The function returns the number of bytes 1748 * remaining, excluding any that libpng has cached internally. A subsequent 1749 * call to png_process_data must supply these bytes again. If the argument 1750 * 'save' is set to true the routine will first save all the pending data and 1751 * will always return 0. 1752 */ 1753PNG_EXPORT(219, png_size_t, png_process_data_pause, (png_structrp, int save)); 1754 1755/* A function which may be called *only* outside (after) a call to 1756 * png_process_data. It returns the number of bytes of data to skip in the 1757 * input. Normally it will return 0, but if it returns a non-zero value the 1758 * application must skip than number of bytes of input data and pass the 1759 * following data to the next call to png_process_data. 1760 */ 1761PNG_EXPORT(220, png_uint_32, png_process_data_skip, (png_structrp)); 1762 1763/* Function that combines rows. 'new_row' is a flag that should come from 1764 * the callback and be non-NULL if anything needs to be done; the library 1765 * stores its own version of the new data internally and ignores the passed 1766 * in value. 1767 */ 1768PNG_EXPORT(93, void, png_progressive_combine_row, (png_const_structrp png_ptr, 1769 png_bytep old_row, png_const_bytep new_row)); 1770#endif /* PROGRESSIVE_READ */ 1771 1772PNG_EXPORTA(94, png_voidp, png_malloc, (png_const_structrp png_ptr, 1773 png_alloc_size_t size), PNG_ALLOCATED); 1774/* Added at libpng version 1.4.0 */ 1775PNG_EXPORTA(95, png_voidp, png_calloc, (png_const_structrp png_ptr, 1776 png_alloc_size_t size), PNG_ALLOCATED); 1777 1778/* Added at libpng version 1.2.4 */ 1779PNG_EXPORTA(96, png_voidp, png_malloc_warn, (png_const_structrp png_ptr, 1780 png_alloc_size_t size), PNG_ALLOCATED); 1781 1782/* Frees a pointer allocated by png_malloc() */ 1783PNG_EXPORT(97, void, png_free, (png_const_structrp png_ptr, png_voidp ptr)); 1784 1785/* Free data that was allocated internally */ 1786PNG_EXPORT(98, void, png_free_data, (png_const_structrp png_ptr, 1787 png_inforp info_ptr, png_uint_32 free_me, int num)); 1788 1789/* Reassign responsibility for freeing existing data, whether allocated 1790 * by libpng or by the application; this works on the png_info structure passed 1791 * in, it does not change the state for other png_info structures. 1792 * 1793 * It is unlikely that this function works correctly as of 1.6.0 and using it 1794 * may result either in memory leaks or double free of allocated data. 1795 */ 1796PNG_EXPORT(99, void, png_data_freer, (png_const_structrp png_ptr, 1797 png_inforp info_ptr, int freer, png_uint_32 mask)); 1798 1799/* Assignments for png_data_freer */ 1800#define PNG_DESTROY_WILL_FREE_DATA 1 1801#define PNG_SET_WILL_FREE_DATA 1 1802#define PNG_USER_WILL_FREE_DATA 2 1803/* Flags for png_ptr->free_me and info_ptr->free_me */ 1804#define PNG_FREE_HIST 0x0008U 1805#define PNG_FREE_ICCP 0x0010U 1806#define PNG_FREE_SPLT 0x0020U 1807#define PNG_FREE_ROWS 0x0040U 1808#define PNG_FREE_PCAL 0x0080U 1809#define PNG_FREE_SCAL 0x0100U 1810#ifdef PNG_STORE_UNKNOWN_CHUNKS_SUPPORTED 1811# define PNG_FREE_UNKN 0x0200U 1812#endif 1813/* PNG_FREE_LIST 0x0400U removed in 1.6.0 because it is ignored */ 1814#define PNG_FREE_PLTE 0x1000U 1815#define PNG_FREE_TRNS 0x2000U 1816#define PNG_FREE_TEXT 0x4000U 1817#define PNG_FREE_ALL 0x7fffU 1818#define PNG_FREE_MUL 0x4220U /* PNG_FREE_SPLT|PNG_FREE_TEXT|PNG_FREE_UNKN */ 1819 1820#ifdef PNG_USER_MEM_SUPPORTED 1821PNG_EXPORTA(100, png_voidp, png_malloc_default, (png_const_structrp png_ptr, 1822 png_alloc_size_t size), PNG_ALLOCATED PNG_DEPRECATED); 1823PNG_EXPORTA(101, void, png_free_default, (png_const_structrp png_ptr, 1824 png_voidp ptr), PNG_DEPRECATED); 1825#endif 1826 1827#ifdef PNG_ERROR_TEXT_SUPPORTED 1828/* Fatal error in PNG image of libpng - can't continue */ 1829PNG_EXPORTA(102, void, png_error, (png_const_structrp png_ptr, 1830 png_const_charp error_message), PNG_NORETURN); 1831 1832/* The same, but the chunk name is prepended to the error string. */ 1833PNG_EXPORTA(103, void, png_chunk_error, (png_const_structrp png_ptr, 1834 png_const_charp error_message), PNG_NORETURN); 1835 1836#else 1837/* Fatal error in PNG image of libpng - can't continue */ 1838PNG_EXPORTA(104, void, png_err, (png_const_structrp png_ptr), PNG_NORETURN); 1839# define png_error(s1,s2) png_err(s1) 1840# define png_chunk_error(s1,s2) png_err(s1) 1841#endif 1842 1843#ifdef PNG_WARNINGS_SUPPORTED 1844/* Non-fatal error in libpng. Can continue, but may have a problem. */ 1845PNG_EXPORT(105, void, png_warning, (png_const_structrp png_ptr, 1846 png_const_charp warning_message)); 1847 1848/* Non-fatal error in libpng, chunk name is prepended to message. */ 1849PNG_EXPORT(106, void, png_chunk_warning, (png_const_structrp png_ptr, 1850 png_const_charp warning_message)); 1851#else 1852# define png_warning(s1,s2) ((void)(s1)) 1853# define png_chunk_warning(s1,s2) ((void)(s1)) 1854#endif 1855 1856#ifdef PNG_BENIGN_ERRORS_SUPPORTED 1857/* Benign error in libpng. Can continue, but may have a problem. 1858 * User can choose whether to handle as a fatal error or as a warning. */ 1859PNG_EXPORT(107, void, png_benign_error, (png_const_structrp png_ptr, 1860 png_const_charp warning_message)); 1861 1862#ifdef PNG_READ_SUPPORTED 1863/* Same, chunk name is prepended to message (only during read) */ 1864PNG_EXPORT(108, void, png_chunk_benign_error, (png_const_structrp png_ptr, 1865 png_const_charp warning_message)); 1866#endif 1867 1868PNG_EXPORT(109, void, png_set_benign_errors, 1869 (png_structrp png_ptr, int allowed)); 1870#else 1871# ifdef PNG_ALLOW_BENIGN_ERRORS 1872# define png_benign_error png_warning 1873# define png_chunk_benign_error png_chunk_warning 1874# else 1875# define png_benign_error png_error 1876# define png_chunk_benign_error png_chunk_error 1877# endif 1878#endif 1879 1880/* The png_set_<chunk> functions are for storing values in the png_info_struct. 1881 * Similarly, the png_get_<chunk> calls are used to read values from the 1882 * png_info_struct, either storing the parameters in the passed variables, or 1883 * setting pointers into the png_info_struct where the data is stored. The 1884 * png_get_<chunk> functions return a non-zero value if the data was available 1885 * in info_ptr, or return zero and do not change any of the parameters if the 1886 * data was not available. 1887 * 1888 * These functions should be used instead of directly accessing png_info 1889 * to avoid problems with future changes in the size and internal layout of 1890 * png_info_struct. 1891 */ 1892/* Returns "flag" if chunk data is valid in info_ptr. */ 1893PNG_EXPORT(110, png_uint_32, png_get_valid, (png_const_structrp png_ptr, 1894 png_const_inforp info_ptr, png_uint_32 flag)); 1895 1896/* Returns number of bytes needed to hold a transformed row. */ 1897PNG_EXPORT(111, png_size_t, png_get_rowbytes, (png_const_structrp png_ptr, 1898 png_const_inforp info_ptr)); 1899 1900#ifdef PNG_INFO_IMAGE_SUPPORTED 1901/* Returns row_pointers, which is an array of pointers to scanlines that was 1902 * returned from png_read_png(). 1903 */ 1904PNG_EXPORT(112, png_bytepp, png_get_rows, (png_const_structrp png_ptr, 1905 png_const_inforp info_ptr)); 1906 1907/* Set row_pointers, which is an array of pointers to scanlines for use 1908 * by png_write_png(). 1909 */ 1910PNG_EXPORT(113, void, png_set_rows, (png_const_structrp png_ptr, 1911 png_inforp info_ptr, png_bytepp row_pointers)); 1912#endif 1913 1914/* Returns number of color channels in image. */ 1915PNG_EXPORT(114, png_byte, png_get_channels, (png_const_structrp png_ptr, 1916 png_const_inforp info_ptr)); 1917 1918#ifdef PNG_EASY_ACCESS_SUPPORTED 1919/* Returns image width in pixels. */ 1920PNG_EXPORT(115, png_uint_32, png_get_image_width, (png_const_structrp png_ptr, 1921 png_const_inforp info_ptr)); 1922 1923/* Returns image height in pixels. */ 1924PNG_EXPORT(116, png_uint_32, png_get_image_height, (png_const_structrp png_ptr, 1925 png_const_inforp info_ptr)); 1926 1927/* Returns image bit_depth. */ 1928PNG_EXPORT(117, png_byte, png_get_bit_depth, (png_const_structrp png_ptr, 1929 png_const_inforp info_ptr)); 1930 1931/* Returns image color_type. */ 1932PNG_EXPORT(118, png_byte, png_get_color_type, (png_const_structrp png_ptr, 1933 png_const_inforp info_ptr)); 1934 1935/* Returns image filter_type. */ 1936PNG_EXPORT(119, png_byte, png_get_filter_type, (png_const_structrp png_ptr, 1937 png_const_inforp info_ptr)); 1938 1939/* Returns image interlace_type. */ 1940PNG_EXPORT(120, png_byte, png_get_interlace_type, (png_const_structrp png_ptr, 1941 png_const_inforp info_ptr)); 1942 1943/* Returns image compression_type. */ 1944PNG_EXPORT(121, png_byte, png_get_compression_type, (png_const_structrp png_ptr, 1945 png_const_inforp info_ptr)); 1946 1947/* Returns image resolution in pixels per meter, from pHYs chunk data. */ 1948PNG_EXPORT(122, png_uint_32, png_get_pixels_per_meter, 1949 (png_const_structrp png_ptr, png_const_inforp info_ptr)); 1950PNG_EXPORT(123, png_uint_32, png_get_x_pixels_per_meter, 1951 (png_const_structrp png_ptr, png_const_inforp info_ptr)); 1952PNG_EXPORT(124, png_uint_32, png_get_y_pixels_per_meter, 1953 (png_const_structrp png_ptr, png_const_inforp info_ptr)); 1954 1955/* Returns pixel aspect ratio, computed from pHYs chunk data. */ 1956PNG_FP_EXPORT(125, float, png_get_pixel_aspect_ratio, 1957 (png_const_structrp png_ptr, png_const_inforp info_ptr)) 1958PNG_FIXED_EXPORT(210, png_fixed_point, png_get_pixel_aspect_ratio_fixed, 1959 (png_const_structrp png_ptr, png_const_inforp info_ptr)) 1960 1961/* Returns image x, y offset in pixels or microns, from oFFs chunk data. */ 1962PNG_EXPORT(126, png_int_32, png_get_x_offset_pixels, 1963 (png_const_structrp png_ptr, png_const_inforp info_ptr)); 1964PNG_EXPORT(127, png_int_32, png_get_y_offset_pixels, 1965 (png_const_structrp png_ptr, png_const_inforp info_ptr)); 1966PNG_EXPORT(128, png_int_32, png_get_x_offset_microns, 1967 (png_const_structrp png_ptr, png_const_inforp info_ptr)); 1968PNG_EXPORT(129, png_int_32, png_get_y_offset_microns, 1969 (png_const_structrp png_ptr, png_const_inforp info_ptr)); 1970 1971#endif /* EASY_ACCESS */ 1972 1973#ifdef PNG_READ_SUPPORTED 1974/* Returns pointer to signature string read from PNG header */ 1975PNG_EXPORT(130, png_const_bytep, png_get_signature, (png_const_structrp png_ptr, 1976 png_const_inforp info_ptr)); 1977#endif 1978 1979#ifdef PNG_bKGD_SUPPORTED 1980PNG_EXPORT(131, png_uint_32, png_get_bKGD, (png_const_structrp png_ptr, 1981 png_inforp info_ptr, png_color_16p *background)); 1982#endif 1983 1984#ifdef PNG_bKGD_SUPPORTED 1985PNG_EXPORT(132, void, png_set_bKGD, (png_const_structrp png_ptr, 1986 png_inforp info_ptr, png_const_color_16p background)); 1987#endif 1988 1989#ifdef PNG_cHRM_SUPPORTED 1990PNG_FP_EXPORT(133, png_uint_32, png_get_cHRM, (png_const_structrp png_ptr, 1991 png_const_inforp info_ptr, double *white_x, double *white_y, double *red_x, 1992 double *red_y, double *green_x, double *green_y, double *blue_x, 1993 double *blue_y)) 1994PNG_FP_EXPORT(230, png_uint_32, png_get_cHRM_XYZ, (png_const_structrp png_ptr, 1995 png_const_inforp info_ptr, double *red_X, double *red_Y, double *red_Z, 1996 double *green_X, double *green_Y, double *green_Z, double *blue_X, 1997 double *blue_Y, double *blue_Z)) 1998PNG_FIXED_EXPORT(134, png_uint_32, png_get_cHRM_fixed, 1999 (png_const_structrp png_ptr, png_const_inforp info_ptr, 2000 png_fixed_point *int_white_x, png_fixed_point *int_white_y, 2001 png_fixed_point *int_red_x, png_fixed_point *int_red_y, 2002 png_fixed_point *int_green_x, png_fixed_point *int_green_y, 2003 png_fixed_point *int_blue_x, png_fixed_point *int_blue_y)) 2004PNG_FIXED_EXPORT(231, png_uint_32, png_get_cHRM_XYZ_fixed, 2005 (png_const_structrp png_ptr, png_const_inforp info_ptr, 2006 png_fixed_point *int_red_X, png_fixed_point *int_red_Y, 2007 png_fixed_point *int_red_Z, png_fixed_point *int_green_X, 2008 png_fixed_point *int_green_Y, png_fixed_point *int_green_Z, 2009 png_fixed_point *int_blue_X, png_fixed_point *int_blue_Y, 2010 png_fixed_point *int_blue_Z)) 2011#endif 2012 2013#ifdef PNG_cHRM_SUPPORTED 2014PNG_FP_EXPORT(135, void, png_set_cHRM, (png_const_structrp png_ptr, 2015 png_inforp info_ptr, 2016 double white_x, double white_y, double red_x, double red_y, double green_x, 2017 double green_y, double blue_x, double blue_y)) 2018PNG_FP_EXPORT(232, void, png_set_cHRM_XYZ, (png_const_structrp png_ptr, 2019 png_inforp info_ptr, double red_X, double red_Y, double red_Z, 2020 double green_X, double green_Y, double green_Z, double blue_X, 2021 double blue_Y, double blue_Z)) 2022PNG_FIXED_EXPORT(136, void, png_set_cHRM_fixed, (png_const_structrp png_ptr, 2023 png_inforp info_ptr, png_fixed_point int_white_x, 2024 png_fixed_point int_white_y, png_fixed_point int_red_x, 2025 png_fixed_point int_red_y, png_fixed_point int_green_x, 2026 png_fixed_point int_green_y, png_fixed_point int_blue_x, 2027 png_fixed_point int_blue_y)) 2028PNG_FIXED_EXPORT(233, void, png_set_cHRM_XYZ_fixed, (png_const_structrp png_ptr, 2029 png_inforp info_ptr, png_fixed_point int_red_X, png_fixed_point int_red_Y, 2030 png_fixed_point int_red_Z, png_fixed_point int_green_X, 2031 png_fixed_point int_green_Y, png_fixed_point int_green_Z, 2032 png_fixed_point int_blue_X, png_fixed_point int_blue_Y, 2033 png_fixed_point int_blue_Z)) 2034#endif 2035 2036#ifdef PNG_gAMA_SUPPORTED 2037PNG_FP_EXPORT(137, png_uint_32, png_get_gAMA, (png_const_structrp png_ptr, 2038 png_const_inforp info_ptr, double *file_gamma)) 2039PNG_FIXED_EXPORT(138, png_uint_32, png_get_gAMA_fixed, 2040 (png_const_structrp png_ptr, png_const_inforp info_ptr, 2041 png_fixed_point *int_file_gamma)) 2042#endif 2043 2044#ifdef PNG_gAMA_SUPPORTED 2045PNG_FP_EXPORT(139, void, png_set_gAMA, (png_const_structrp png_ptr, 2046 png_inforp info_ptr, double file_gamma)) 2047PNG_FIXED_EXPORT(140, void, png_set_gAMA_fixed, (png_const_structrp png_ptr, 2048 png_inforp info_ptr, png_fixed_point int_file_gamma)) 2049#endif 2050 2051#ifdef PNG_hIST_SUPPORTED 2052PNG_EXPORT(141, png_uint_32, png_get_hIST, (png_const_structrp png_ptr, 2053 png_inforp info_ptr, png_uint_16p *hist)); 2054#endif 2055 2056#ifdef PNG_hIST_SUPPORTED 2057PNG_EXPORT(142, void, png_set_hIST, (png_const_structrp png_ptr, 2058 png_inforp info_ptr, png_const_uint_16p hist)); 2059#endif 2060 2061PNG_EXPORT(143, png_uint_32, png_get_IHDR, (png_const_structrp png_ptr, 2062 png_const_inforp info_ptr, png_uint_32 *width, png_uint_32 *height, 2063 int *bit_depth, int *color_type, int *interlace_method, 2064 int *compression_method, int *filter_method)); 2065 2066PNG_EXPORT(144, void, png_set_IHDR, (png_const_structrp png_ptr, 2067 png_inforp info_ptr, png_uint_32 width, png_uint_32 height, int bit_depth, 2068 int color_type, int interlace_method, int compression_method, 2069 int filter_method)); 2070 2071#ifdef PNG_oFFs_SUPPORTED 2072PNG_EXPORT(145, png_uint_32, png_get_oFFs, (png_const_structrp png_ptr, 2073 png_const_inforp info_ptr, png_int_32 *offset_x, png_int_32 *offset_y, 2074 int *unit_type)); 2075#endif 2076 2077#ifdef PNG_oFFs_SUPPORTED 2078PNG_EXPORT(146, void, png_set_oFFs, (png_const_structrp png_ptr, 2079 png_inforp info_ptr, png_int_32 offset_x, png_int_32 offset_y, 2080 int unit_type)); 2081#endif 2082 2083#ifdef PNG_pCAL_SUPPORTED 2084PNG_EXPORT(147, png_uint_32, png_get_pCAL, (png_const_structrp png_ptr, 2085 png_inforp info_ptr, png_charp *purpose, png_int_32 *X0, 2086 png_int_32 *X1, int *type, int *nparams, png_charp *units, 2087 png_charpp *params)); 2088#endif 2089 2090#ifdef PNG_pCAL_SUPPORTED 2091PNG_EXPORT(148, void, png_set_pCAL, (png_const_structrp png_ptr, 2092 png_inforp info_ptr, png_const_charp purpose, png_int_32 X0, png_int_32 X1, 2093 int type, int nparams, png_const_charp units, png_charpp params)); 2094#endif 2095 2096#ifdef PNG_pHYs_SUPPORTED 2097PNG_EXPORT(149, png_uint_32, png_get_pHYs, (png_const_structrp png_ptr, 2098 png_const_inforp info_ptr, png_uint_32 *res_x, png_uint_32 *res_y, 2099 int *unit_type)); 2100#endif 2101 2102#ifdef PNG_pHYs_SUPPORTED 2103PNG_EXPORT(150, void, png_set_pHYs, (png_const_structrp png_ptr, 2104 png_inforp info_ptr, png_uint_32 res_x, png_uint_32 res_y, int unit_type)); 2105#endif 2106 2107PNG_EXPORT(151, png_uint_32, png_get_PLTE, (png_const_structrp png_ptr, 2108 png_inforp info_ptr, png_colorp *palette, int *num_palette)); 2109 2110PNG_EXPORT(152, void, png_set_PLTE, (png_structrp png_ptr, 2111 png_inforp info_ptr, png_const_colorp palette, int num_palette)); 2112 2113#ifdef PNG_sBIT_SUPPORTED 2114PNG_EXPORT(153, png_uint_32, png_get_sBIT, (png_const_structrp png_ptr, 2115 png_inforp info_ptr, png_color_8p *sig_bit)); 2116#endif 2117 2118#ifdef PNG_sBIT_SUPPORTED 2119PNG_EXPORT(154, void, png_set_sBIT, (png_const_structrp png_ptr, 2120 png_inforp info_ptr, png_const_color_8p sig_bit)); 2121#endif 2122 2123#ifdef PNG_sRGB_SUPPORTED 2124PNG_EXPORT(155, png_uint_32, png_get_sRGB, (png_const_structrp png_ptr, 2125 png_const_inforp info_ptr, int *file_srgb_intent)); 2126#endif 2127 2128#ifdef PNG_sRGB_SUPPORTED 2129PNG_EXPORT(156, void, png_set_sRGB, (png_const_structrp png_ptr, 2130 png_inforp info_ptr, int srgb_intent)); 2131PNG_EXPORT(157, void, png_set_sRGB_gAMA_and_cHRM, (png_const_structrp png_ptr, 2132 png_inforp info_ptr, int srgb_intent)); 2133#endif 2134 2135#ifdef PNG_iCCP_SUPPORTED 2136PNG_EXPORT(158, png_uint_32, png_get_iCCP, (png_const_structrp png_ptr, 2137 png_inforp info_ptr, png_charpp name, int *compression_type, 2138 png_bytepp profile, png_uint_32 *proflen)); 2139#endif 2140 2141#ifdef PNG_iCCP_SUPPORTED 2142PNG_EXPORT(159, void, png_set_iCCP, (png_const_structrp png_ptr, 2143 png_inforp info_ptr, png_const_charp name, int compression_type, 2144 png_const_bytep profile, png_uint_32 proflen)); 2145#endif 2146 2147#ifdef PNG_sPLT_SUPPORTED 2148PNG_EXPORT(160, int, png_get_sPLT, (png_const_structrp png_ptr, 2149 png_inforp info_ptr, png_sPLT_tpp entries)); 2150#endif 2151 2152#ifdef PNG_sPLT_SUPPORTED 2153PNG_EXPORT(161, void, png_set_sPLT, (png_const_structrp png_ptr, 2154 png_inforp info_ptr, png_const_sPLT_tp entries, int nentries)); 2155#endif 2156 2157#ifdef PNG_TEXT_SUPPORTED 2158/* png_get_text also returns the number of text chunks in *num_text */ 2159PNG_EXPORT(162, int, png_get_text, (png_const_structrp png_ptr, 2160 png_inforp info_ptr, png_textp *text_ptr, int *num_text)); 2161#endif 2162 2163/* Note while png_set_text() will accept a structure whose text, 2164 * language, and translated keywords are NULL pointers, the structure 2165 * returned by png_get_text will always contain regular 2166 * zero-terminated C strings. They might be empty strings but 2167 * they will never be NULL pointers. 2168 */ 2169 2170#ifdef PNG_TEXT_SUPPORTED 2171PNG_EXPORT(163, void, png_set_text, (png_const_structrp png_ptr, 2172 png_inforp info_ptr, png_const_textp text_ptr, int num_text)); 2173#endif 2174 2175#ifdef PNG_tIME_SUPPORTED 2176PNG_EXPORT(164, png_uint_32, png_get_tIME, (png_const_structrp png_ptr, 2177 png_inforp info_ptr, png_timep *mod_time)); 2178#endif 2179 2180#ifdef PNG_tIME_SUPPORTED 2181PNG_EXPORT(165, void, png_set_tIME, (png_const_structrp png_ptr, 2182 png_inforp info_ptr, png_const_timep mod_time)); 2183#endif 2184 2185#ifdef PNG_tRNS_SUPPORTED 2186PNG_EXPORT(166, png_uint_32, png_get_tRNS, (png_const_structrp png_ptr, 2187 png_inforp info_ptr, png_bytep *trans_alpha, int *num_trans, 2188 png_color_16p *trans_color)); 2189#endif 2190 2191#ifdef PNG_tRNS_SUPPORTED 2192PNG_EXPORT(167, void, png_set_tRNS, (png_structrp png_ptr, 2193 png_inforp info_ptr, png_const_bytep trans_alpha, int num_trans, 2194 png_const_color_16p trans_color)); 2195#endif 2196 2197#ifdef PNG_sCAL_SUPPORTED 2198PNG_FP_EXPORT(168, png_uint_32, png_get_sCAL, (png_const_structrp png_ptr, 2199 png_const_inforp info_ptr, int *unit, double *width, double *height)) 2200#if defined(PNG_FLOATING_ARITHMETIC_SUPPORTED) || \ 2201 defined(PNG_FLOATING_POINT_SUPPORTED) 2202/* NOTE: this API is currently implemented using floating point arithmetic, 2203 * consequently it can only be used on systems with floating point support. 2204 * In any case the range of values supported by png_fixed_point is small and it 2205 * is highly recommended that png_get_sCAL_s be used instead. 2206 */ 2207PNG_FIXED_EXPORT(214, png_uint_32, png_get_sCAL_fixed, 2208 (png_const_structrp png_ptr, png_const_inforp info_ptr, int *unit, 2209 png_fixed_point *width, png_fixed_point *height)) 2210#endif 2211PNG_EXPORT(169, png_uint_32, png_get_sCAL_s, 2212 (png_const_structrp png_ptr, png_const_inforp info_ptr, int *unit, 2213 png_charpp swidth, png_charpp sheight)); 2214 2215PNG_FP_EXPORT(170, void, png_set_sCAL, (png_const_structrp png_ptr, 2216 png_inforp info_ptr, int unit, double width, double height)) 2217PNG_FIXED_EXPORT(213, void, png_set_sCAL_fixed, (png_const_structrp png_ptr, 2218 png_inforp info_ptr, int unit, png_fixed_point width, 2219 png_fixed_point height)) 2220PNG_EXPORT(171, void, png_set_sCAL_s, (png_const_structrp png_ptr, 2221 png_inforp info_ptr, int unit, 2222 png_const_charp swidth, png_const_charp sheight)); 2223#endif /* sCAL */ 2224 2225#ifdef PNG_SET_UNKNOWN_CHUNKS_SUPPORTED 2226/* Provide the default handling for all unknown chunks or, optionally, for 2227 * specific unknown chunks. 2228 * 2229 * NOTE: prior to 1.6.0 the handling specified for particular chunks on read was 2230 * ignored and the default was used, the per-chunk setting only had an effect on 2231 * write. If you wish to have chunk-specific handling on read in code that must 2232 * work on earlier versions you must use a user chunk callback to specify the 2233 * desired handling (keep or discard.) 2234 * 2235 * The 'keep' parameter is a PNG_HANDLE_CHUNK_ value as listed below. The 2236 * parameter is interpreted as follows: 2237 * 2238 * READ: 2239 * PNG_HANDLE_CHUNK_AS_DEFAULT: 2240 * Known chunks: do normal libpng processing, do not keep the chunk (but 2241 * see the comments below about PNG_HANDLE_AS_UNKNOWN_SUPPORTED) 2242 * Unknown chunks: for a specific chunk use the global default, when used 2243 * as the default discard the chunk data. 2244 * PNG_HANDLE_CHUNK_NEVER: 2245 * Discard the chunk data. 2246 * PNG_HANDLE_CHUNK_IF_SAFE: 2247 * Keep the chunk data if the chunk is not critical else raise a chunk 2248 * error. 2249 * PNG_HANDLE_CHUNK_ALWAYS: 2250 * Keep the chunk data. 2251 * 2252 * If the chunk data is saved it can be retrieved using png_get_unknown_chunks, 2253 * below. Notice that specifying "AS_DEFAULT" as a global default is equivalent 2254 * to specifying "NEVER", however when "AS_DEFAULT" is used for specific chunks 2255 * it simply resets the behavior to the libpng default. 2256 * 2257 * INTERACTION WTIH USER CHUNK CALLBACKS: 2258 * The per-chunk handling is always used when there is a png_user_chunk_ptr 2259 * callback and the callback returns 0; the chunk is then always stored *unless* 2260 * it is critical and the per-chunk setting is other than ALWAYS. Notice that 2261 * the global default is *not* used in this case. (In effect the per-chunk 2262 * value is incremented to at least IF_SAFE.) 2263 * 2264 * IMPORTANT NOTE: this behavior will change in libpng 1.7 - the global and 2265 * per-chunk defaults will be honored. If you want to preserve the current 2266 * behavior when your callback returns 0 you must set PNG_HANDLE_CHUNK_IF_SAFE 2267 * as the default - if you don't do this libpng 1.6 will issue a warning. 2268 * 2269 * If you want unhandled unknown chunks to be discarded in libpng 1.6 and 2270 * earlier simply return '1' (handled). 2271 * 2272 * PNG_HANDLE_AS_UNKNOWN_SUPPORTED: 2273 * If this is *not* set known chunks will always be handled by libpng and 2274 * will never be stored in the unknown chunk list. Known chunks listed to 2275 * png_set_keep_unknown_chunks will have no effect. If it is set then known 2276 * chunks listed with a keep other than AS_DEFAULT will *never* be processed 2277 * by libpng, in addition critical chunks must either be processed by the 2278 * callback or saved. 2279 * 2280 * The IHDR and IEND chunks must not be listed. Because this turns off the 2281 * default handling for chunks that would otherwise be recognized the 2282 * behavior of libpng transformations may well become incorrect! 2283 * 2284 * WRITE: 2285 * When writing chunks the options only apply to the chunks specified by 2286 * png_set_unknown_chunks (below), libpng will *always* write known chunks 2287 * required by png_set_ calls and will always write the core critical chunks 2288 * (as required for PLTE). 2289 * 2290 * Each chunk in the png_set_unknown_chunks list is looked up in the 2291 * png_set_keep_unknown_chunks list to find the keep setting, this is then 2292 * interpreted as follows: 2293 * 2294 * PNG_HANDLE_CHUNK_AS_DEFAULT: 2295 * Write safe-to-copy chunks and write other chunks if the global 2296 * default is set to _ALWAYS, otherwise don't write this chunk. 2297 * PNG_HANDLE_CHUNK_NEVER: 2298 * Do not write the chunk. 2299 * PNG_HANDLE_CHUNK_IF_SAFE: 2300 * Write the chunk if it is safe-to-copy, otherwise do not write it. 2301 * PNG_HANDLE_CHUNK_ALWAYS: 2302 * Write the chunk. 2303 * 2304 * Note that the default behavior is effectively the opposite of the read case - 2305 * in read unknown chunks are not stored by default, in write they are written 2306 * by default. Also the behavior of PNG_HANDLE_CHUNK_IF_SAFE is very different 2307 * - on write the safe-to-copy bit is checked, on read the critical bit is 2308 * checked and on read if the chunk is critical an error will be raised. 2309 * 2310 * num_chunks: 2311 * =========== 2312 * If num_chunks is positive, then the "keep" parameter specifies the manner 2313 * for handling only those chunks appearing in the chunk_list array, 2314 * otherwise the chunk list array is ignored. 2315 * 2316 * If num_chunks is 0 the "keep" parameter specifies the default behavior for 2317 * unknown chunks, as described above. 2318 * 2319 * If num_chunks is negative, then the "keep" parameter specifies the manner 2320 * for handling all unknown chunks plus all chunks recognized by libpng 2321 * except for the IHDR, PLTE, tRNS, IDAT, and IEND chunks (which continue to 2322 * be processed by libpng. 2323 */ 2324#ifdef PNG_HANDLE_AS_UNKNOWN_SUPPORTED 2325PNG_EXPORT(172, void, png_set_keep_unknown_chunks, (png_structrp png_ptr, 2326 int keep, png_const_bytep chunk_list, int num_chunks)); 2327#endif /* HANDLE_AS_UNKNOWN */ 2328 2329/* The "keep" PNG_HANDLE_CHUNK_ parameter for the specified chunk is returned; 2330 * the result is therefore true (non-zero) if special handling is required, 2331 * false for the default handling. 2332 */ 2333PNG_EXPORT(173, int, png_handle_as_unknown, (png_const_structrp png_ptr, 2334 png_const_bytep chunk_name)); 2335#endif /* SET_UNKNOWN_CHUNKS */ 2336 2337#ifdef PNG_STORE_UNKNOWN_CHUNKS_SUPPORTED 2338PNG_EXPORT(174, void, png_set_unknown_chunks, (png_const_structrp png_ptr, 2339 png_inforp info_ptr, png_const_unknown_chunkp unknowns, 2340 int num_unknowns)); 2341 /* NOTE: prior to 1.6.0 this routine set the 'location' field of the added 2342 * unknowns to the location currently stored in the png_struct. This is 2343 * invariably the wrong value on write. To fix this call the following API 2344 * for each chunk in the list with the correct location. If you know your 2345 * code won't be compiled on earlier versions you can rely on 2346 * png_set_unknown_chunks(write-ptr, png_get_unknown_chunks(read-ptr)) doing 2347 * the correct thing. 2348 */ 2349 2350PNG_EXPORT(175, void, png_set_unknown_chunk_location, 2351 (png_const_structrp png_ptr, png_inforp info_ptr, int chunk, int location)); 2352 2353PNG_EXPORT(176, int, png_get_unknown_chunks, (png_const_structrp png_ptr, 2354 png_inforp info_ptr, png_unknown_chunkpp entries)); 2355#endif 2356 2357/* Png_free_data() will turn off the "valid" flag for anything it frees. 2358 * If you need to turn it off for a chunk that your application has freed, 2359 * you can use png_set_invalid(png_ptr, info_ptr, PNG_INFO_CHNK); 2360 */ 2361PNG_EXPORT(177, void, png_set_invalid, (png_const_structrp png_ptr, 2362 png_inforp info_ptr, int mask)); 2363 2364#ifdef PNG_INFO_IMAGE_SUPPORTED 2365/* The "params" pointer is currently not used and is for future expansion. */ 2366#ifdef PNG_SEQUENTIAL_READ_SUPPORTED 2367PNG_EXPORT(178, void, png_read_png, (png_structrp png_ptr, png_inforp info_ptr, 2368 int transforms, png_voidp params)); 2369#endif 2370#ifdef PNG_WRITE_SUPPORTED 2371PNG_EXPORT(179, void, png_write_png, (png_structrp png_ptr, png_inforp info_ptr, 2372 int transforms, png_voidp params)); 2373#endif 2374#endif 2375 2376PNG_EXPORT(180, png_const_charp, png_get_copyright, 2377 (png_const_structrp png_ptr)); 2378PNG_EXPORT(181, png_const_charp, png_get_header_ver, 2379 (png_const_structrp png_ptr)); 2380PNG_EXPORT(182, png_const_charp, png_get_header_version, 2381 (png_const_structrp png_ptr)); 2382PNG_EXPORT(183, png_const_charp, png_get_libpng_ver, 2383 (png_const_structrp png_ptr)); 2384 2385#ifdef PNG_MNG_FEATURES_SUPPORTED 2386PNG_EXPORT(184, png_uint_32, png_permit_mng_features, (png_structrp png_ptr, 2387 png_uint_32 mng_features_permitted)); 2388#endif 2389 2390/* For use in png_set_keep_unknown, added to version 1.2.6 */ 2391#define PNG_HANDLE_CHUNK_AS_DEFAULT 0 2392#define PNG_HANDLE_CHUNK_NEVER 1 2393#define PNG_HANDLE_CHUNK_IF_SAFE 2 2394#define PNG_HANDLE_CHUNK_ALWAYS 3 2395#define PNG_HANDLE_CHUNK_LAST 4 2396 2397/* Strip the prepended error numbers ("#nnn ") from error and warning 2398 * messages before passing them to the error or warning handler. 2399 */ 2400#ifdef PNG_ERROR_NUMBERS_SUPPORTED 2401PNG_EXPORT(185, void, png_set_strip_error_numbers, (png_structrp png_ptr, 2402 png_uint_32 strip_mode)); 2403#endif 2404 2405/* Added in libpng-1.2.6 */ 2406#ifdef PNG_SET_USER_LIMITS_SUPPORTED 2407PNG_EXPORT(186, void, png_set_user_limits, (png_structrp png_ptr, 2408 png_uint_32 user_width_max, png_uint_32 user_height_max)); 2409PNG_EXPORT(187, png_uint_32, png_get_user_width_max, 2410 (png_const_structrp png_ptr)); 2411PNG_EXPORT(188, png_uint_32, png_get_user_height_max, 2412 (png_const_structrp png_ptr)); 2413/* Added in libpng-1.4.0 */ 2414PNG_EXPORT(189, void, png_set_chunk_cache_max, (png_structrp png_ptr, 2415 png_uint_32 user_chunk_cache_max)); 2416PNG_EXPORT(190, png_uint_32, png_get_chunk_cache_max, 2417 (png_const_structrp png_ptr)); 2418/* Added in libpng-1.4.1 */ 2419PNG_EXPORT(191, void, png_set_chunk_malloc_max, (png_structrp png_ptr, 2420 png_alloc_size_t user_chunk_cache_max)); 2421PNG_EXPORT(192, png_alloc_size_t, png_get_chunk_malloc_max, 2422 (png_const_structrp png_ptr)); 2423#endif 2424 2425#if defined(PNG_INCH_CONVERSIONS_SUPPORTED) 2426PNG_EXPORT(193, png_uint_32, png_get_pixels_per_inch, 2427 (png_const_structrp png_ptr, png_const_inforp info_ptr)); 2428 2429PNG_EXPORT(194, png_uint_32, png_get_x_pixels_per_inch, 2430 (png_const_structrp png_ptr, png_const_inforp info_ptr)); 2431 2432PNG_EXPORT(195, png_uint_32, png_get_y_pixels_per_inch, 2433 (png_const_structrp png_ptr, png_const_inforp info_ptr)); 2434 2435PNG_FP_EXPORT(196, float, png_get_x_offset_inches, 2436 (png_const_structrp png_ptr, png_const_inforp info_ptr)) 2437#ifdef PNG_FIXED_POINT_SUPPORTED /* otherwise not implemented. */ 2438PNG_FIXED_EXPORT(211, png_fixed_point, png_get_x_offset_inches_fixed, 2439 (png_const_structrp png_ptr, png_const_inforp info_ptr)) 2440#endif 2441 2442PNG_FP_EXPORT(197, float, png_get_y_offset_inches, (png_const_structrp png_ptr, 2443 png_const_inforp info_ptr)) 2444#ifdef PNG_FIXED_POINT_SUPPORTED /* otherwise not implemented. */ 2445PNG_FIXED_EXPORT(212, png_fixed_point, png_get_y_offset_inches_fixed, 2446 (png_const_structrp png_ptr, png_const_inforp info_ptr)) 2447#endif 2448 2449# ifdef PNG_pHYs_SUPPORTED 2450PNG_EXPORT(198, png_uint_32, png_get_pHYs_dpi, (png_const_structrp png_ptr, 2451 png_const_inforp info_ptr, png_uint_32 *res_x, png_uint_32 *res_y, 2452 int *unit_type)); 2453# endif /* pHYs */ 2454#endif /* INCH_CONVERSIONS */ 2455 2456/* Added in libpng-1.4.0 */ 2457#ifdef PNG_IO_STATE_SUPPORTED 2458PNG_EXPORT(199, png_uint_32, png_get_io_state, (png_const_structrp png_ptr)); 2459 2460/* Removed from libpng 1.6; use png_get_io_chunk_type. */ 2461PNG_REMOVED(200, png_const_bytep, png_get_io_chunk_name, (png_structrp png_ptr), 2462 PNG_DEPRECATED) 2463 2464PNG_EXPORT(216, png_uint_32, png_get_io_chunk_type, 2465 (png_const_structrp png_ptr)); 2466 2467/* The flags returned by png_get_io_state() are the following: */ 2468# define PNG_IO_NONE 0x0000 /* no I/O at this moment */ 2469# define PNG_IO_READING 0x0001 /* currently reading */ 2470# define PNG_IO_WRITING 0x0002 /* currently writing */ 2471# define PNG_IO_SIGNATURE 0x0010 /* currently at the file signature */ 2472# define PNG_IO_CHUNK_HDR 0x0020 /* currently at the chunk header */ 2473# define PNG_IO_CHUNK_DATA 0x0040 /* currently at the chunk data */ 2474# define PNG_IO_CHUNK_CRC 0x0080 /* currently at the chunk crc */ 2475# define PNG_IO_MASK_OP 0x000f /* current operation: reading/writing */ 2476# define PNG_IO_MASK_LOC 0x00f0 /* current location: sig/hdr/data/crc */ 2477#endif /* IO_STATE */ 2478 2479/* Interlace support. The following macros are always defined so that if 2480 * libpng interlace handling is turned off the macros may be used to handle 2481 * interlaced images within the application. 2482 */ 2483#define PNG_INTERLACE_ADAM7_PASSES 7 2484 2485/* Two macros to return the first row and first column of the original, 2486 * full, image which appears in a given pass. 'pass' is in the range 0 2487 * to 6 and the result is in the range 0 to 7. 2488 */ 2489#define PNG_PASS_START_ROW(pass) (((1&~(pass))<<(3-((pass)>>1)))&7) 2490#define PNG_PASS_START_COL(pass) (((1& (pass))<<(3-(((pass)+1)>>1)))&7) 2491 2492/* A macro to return the offset between pixels in the output row for a pair of 2493 * pixels in the input - effectively the inverse of the 'COL_SHIFT' macro that 2494 * follows. Note that ROW_OFFSET is the offset from one row to the next whereas 2495 * COL_OFFSET is from one column to the next, within a row. 2496 */ 2497#define PNG_PASS_ROW_OFFSET(pass) ((pass)>2?(8>>(((pass)-1)>>1)):8) 2498#define PNG_PASS_COL_OFFSET(pass) (1<<((7-(pass))>>1)) 2499 2500/* Two macros to help evaluate the number of rows or columns in each 2501 * pass. This is expressed as a shift - effectively log2 of the number or 2502 * rows or columns in each 8x8 tile of the original image. 2503 */ 2504#define PNG_PASS_ROW_SHIFT(pass) ((pass)>2?(8-(pass))>>1:3) 2505#define PNG_PASS_COL_SHIFT(pass) ((pass)>1?(7-(pass))>>1:3) 2506 2507/* Hence two macros to determine the number of rows or columns in a given 2508 * pass of an image given its height or width. In fact these macros may 2509 * return non-zero even though the sub-image is empty, because the other 2510 * dimension may be empty for a small image. 2511 */ 2512#define PNG_PASS_ROWS(height, pass) (((height)+(((1<<PNG_PASS_ROW_SHIFT(pass))\ 2513 -1)-PNG_PASS_START_ROW(pass)))>>PNG_PASS_ROW_SHIFT(pass)) 2514#define PNG_PASS_COLS(width, pass) (((width)+(((1<<PNG_PASS_COL_SHIFT(pass))\ 2515 -1)-PNG_PASS_START_COL(pass)))>>PNG_PASS_COL_SHIFT(pass)) 2516 2517/* For the reader row callbacks (both progressive and sequential) it is 2518 * necessary to find the row in the output image given a row in an interlaced 2519 * image, so two more macros: 2520 */ 2521#define PNG_ROW_FROM_PASS_ROW(y_in, pass) \ 2522 (((y_in)<<PNG_PASS_ROW_SHIFT(pass))+PNG_PASS_START_ROW(pass)) 2523#define PNG_COL_FROM_PASS_COL(x_in, pass) \ 2524 (((x_in)<<PNG_PASS_COL_SHIFT(pass))+PNG_PASS_START_COL(pass)) 2525 2526/* Two macros which return a boolean (0 or 1) saying whether the given row 2527 * or column is in a particular pass. These use a common utility macro that 2528 * returns a mask for a given pass - the offset 'off' selects the row or 2529 * column version. The mask has the appropriate bit set for each column in 2530 * the tile. 2531 */ 2532#define PNG_PASS_MASK(pass,off) ( \ 2533 ((0x110145AF>>(((7-(off))-(pass))<<2)) & 0xF) | \ 2534 ((0x01145AF0>>(((7-(off))-(pass))<<2)) & 0xF0)) 2535 2536#define PNG_ROW_IN_INTERLACE_PASS(y, pass) \ 2537 ((PNG_PASS_MASK(pass,0) >> ((y)&7)) & 1) 2538#define PNG_COL_IN_INTERLACE_PASS(x, pass) \ 2539 ((PNG_PASS_MASK(pass,1) >> ((x)&7)) & 1) 2540 2541#ifdef PNG_READ_COMPOSITE_NODIV_SUPPORTED 2542/* With these routines we avoid an integer divide, which will be slower on 2543 * most machines. However, it does take more operations than the corresponding 2544 * divide method, so it may be slower on a few RISC systems. There are two 2545 * shifts (by 8 or 16 bits) and an addition, versus a single integer divide. 2546 * 2547 * Note that the rounding factors are NOT supposed to be the same! 128 and 2548 * 32768 are correct for the NODIV code; 127 and 32767 are correct for the 2549 * standard method. 2550 * 2551 * [Optimized code by Greg Roelofs and Mark Adler...blame us for bugs. :-) ] 2552 */ 2553 2554 /* fg and bg should be in `gamma 1.0' space; alpha is the opacity */ 2555 2556# define png_composite(composite, fg, alpha, bg) \ 2557 { \ 2558 png_uint_16 temp = (png_uint_16)((png_uint_16)(fg) \ 2559 * (png_uint_16)(alpha) \ 2560 + (png_uint_16)(bg)*(png_uint_16)(255 \ 2561 - (png_uint_16)(alpha)) + 128); \ 2562 (composite) = (png_byte)(((temp + (temp >> 8)) >> 8) & 0xff); \ 2563 } 2564 2565# define png_composite_16(composite, fg, alpha, bg) \ 2566 { \ 2567 png_uint_32 temp = (png_uint_32)((png_uint_32)(fg) \ 2568 * (png_uint_32)(alpha) \ 2569 + (png_uint_32)(bg)*(65535 \ 2570 - (png_uint_32)(alpha)) + 32768); \ 2571 (composite) = (png_uint_16)(0xffff & ((temp + (temp >> 16)) >> 16)); \ 2572 } 2573 2574#else /* Standard method using integer division */ 2575 2576# define png_composite(composite, fg, alpha, bg) \ 2577 (composite) = \ 2578 (png_byte)(0xff & (((png_uint_16)(fg) * (png_uint_16)(alpha) + \ 2579 (png_uint_16)(bg) * (png_uint_16)(255 - (png_uint_16)(alpha)) + \ 2580 127) / 255)) 2581 2582# define png_composite_16(composite, fg, alpha, bg) \ 2583 (composite) = \ 2584 (png_uint_16)(0xffff & (((png_uint_32)(fg) * (png_uint_32)(alpha) + \ 2585 (png_uint_32)(bg)*(png_uint_32)(65535 - (png_uint_32)(alpha)) + \ 2586 32767) / 65535)) 2587#endif /* READ_COMPOSITE_NODIV */ 2588 2589#ifdef PNG_READ_INT_FUNCTIONS_SUPPORTED 2590PNG_EXPORT(201, png_uint_32, png_get_uint_32, (png_const_bytep buf)); 2591PNG_EXPORT(202, png_uint_16, png_get_uint_16, (png_const_bytep buf)); 2592PNG_EXPORT(203, png_int_32, png_get_int_32, (png_const_bytep buf)); 2593#endif 2594 2595PNG_EXPORT(204, png_uint_32, png_get_uint_31, (png_const_structrp png_ptr, 2596 png_const_bytep buf)); 2597/* No png_get_int_16 -- may be added if there's a real need for it. */ 2598 2599/* Place a 32-bit number into a buffer in PNG byte order (big-endian). */ 2600#ifdef PNG_WRITE_INT_FUNCTIONS_SUPPORTED 2601PNG_EXPORT(205, void, png_save_uint_32, (png_bytep buf, png_uint_32 i)); 2602#endif 2603#ifdef PNG_SAVE_INT_32_SUPPORTED 2604PNG_EXPORT(206, void, png_save_int_32, (png_bytep buf, png_int_32 i)); 2605#endif 2606 2607/* Place a 16-bit number into a buffer in PNG byte order. 2608 * The parameter is declared unsigned int, not png_uint_16, 2609 * just to avoid potential problems on pre-ANSI C compilers. 2610 */ 2611#ifdef PNG_WRITE_INT_FUNCTIONS_SUPPORTED 2612PNG_EXPORT(207, void, png_save_uint_16, (png_bytep buf, unsigned int i)); 2613/* No png_save_int_16 -- may be added if there's a real need for it. */ 2614#endif 2615 2616#ifdef PNG_USE_READ_MACROS 2617/* Inline macros to do direct reads of bytes from the input buffer. 2618 * The png_get_int_32() routine assumes we are using two's complement 2619 * format for negative values, which is almost certainly true. 2620 */ 2621# define PNG_get_uint_32(buf) \ 2622 (((png_uint_32)(*(buf)) << 24) + \ 2623 ((png_uint_32)(*((buf) + 1)) << 16) + \ 2624 ((png_uint_32)(*((buf) + 2)) << 8) + \ 2625 ((png_uint_32)(*((buf) + 3)))) 2626 2627 /* From libpng-1.4.0 until 1.4.4, the png_get_uint_16 macro (but not the 2628 * function) incorrectly returned a value of type png_uint_32. 2629 */ 2630# define PNG_get_uint_16(buf) \ 2631 ((png_uint_16) \ 2632 (((unsigned int)(*(buf)) << 8) + \ 2633 ((unsigned int)(*((buf) + 1))))) 2634 2635# define PNG_get_int_32(buf) \ 2636 ((png_int_32)((*(buf) & 0x80) \ 2637 ? -((png_int_32)(((png_get_uint_32(buf)^0xffffffffU)+1U)&0x7fffffffU)) \ 2638 : (png_int_32)png_get_uint_32(buf))) 2639 2640/* If PNG_PREFIX is defined the same thing as below happens in pnglibconf.h, 2641 * but defining a macro name prefixed with PNG_PREFIX. 2642 */ 2643# ifndef PNG_PREFIX 2644# define png_get_uint_32(buf) PNG_get_uint_32(buf) 2645# define png_get_uint_16(buf) PNG_get_uint_16(buf) 2646# define png_get_int_32(buf) PNG_get_int_32(buf) 2647# endif 2648#else 2649# ifdef PNG_PREFIX 2650 /* No macros; revert to the (redefined) function */ 2651# define PNG_get_uint_32 (png_get_uint_32) 2652# define PNG_get_uint_16 (png_get_uint_16) 2653# define PNG_get_int_32 (png_get_int_32) 2654# endif 2655#endif 2656 2657#ifdef PNG_CHECK_FOR_INVALID_INDEX_SUPPORTED 2658PNG_EXPORT(242, void, png_set_check_for_invalid_index, 2659 (png_structrp png_ptr, int allowed)); 2660# ifdef PNG_GET_PALETTE_MAX_SUPPORTED 2661PNG_EXPORT(243, int, png_get_palette_max, (png_const_structp png_ptr, 2662 png_const_infop info_ptr)); 2663# endif 2664#endif /* CHECK_FOR_INVALID_INDEX */ 2665 2666/******************************************************************************* 2667 * Section 5: SIMPLIFIED API 2668 ******************************************************************************* 2669 * 2670 * Please read the documentation in libpng-manual.txt (TODO: write said 2671 * documentation) if you don't understand what follows. 2672 * 2673 * The simplified API hides the details of both libpng and the PNG file format 2674 * itself. It allows PNG files to be read into a very limited number of 2675 * in-memory bitmap formats or to be written from the same formats. If these 2676 * formats do not accomodate your needs then you can, and should, use the more 2677 * sophisticated APIs above - these support a wide variety of in-memory formats 2678 * and a wide variety of sophisticated transformations to those formats as well 2679 * as a wide variety of APIs to manipulate ancillary information. 2680 * 2681 * To read a PNG file using the simplified API: 2682 * 2683 * 1) Declare a 'png_image' structure (see below) on the stack, set the 2684 * version field to PNG_IMAGE_VERSION and the 'opaque' pointer to NULL 2685 * (this is REQUIRED, your program may crash if you don't do it.) 2686 * 2) Call the appropriate png_image_begin_read... function. 2687 * 3) Set the png_image 'format' member to the required sample format. 2688 * 4) Allocate a buffer for the image and, if required, the color-map. 2689 * 5) Call png_image_finish_read to read the image and, if required, the 2690 * color-map into your buffers. 2691 * 2692 * There are no restrictions on the format of the PNG input itself; all valid 2693 * color types, bit depths, and interlace methods are acceptable, and the 2694 * input image is transformed as necessary to the requested in-memory format 2695 * during the png_image_finish_read() step. The only caveat is that if you 2696 * request a color-mapped image from a PNG that is full-color or makes 2697 * complex use of an alpha channel the transformation is extremely lossy and the 2698 * result may look terrible. 2699 * 2700 * To write a PNG file using the simplified API: 2701 * 2702 * 1) Declare a 'png_image' structure on the stack and memset() it to all zero. 2703 * 2) Initialize the members of the structure that describe the image, setting 2704 * the 'format' member to the format of the image samples. 2705 * 3) Call the appropriate png_image_write... function with a pointer to the 2706 * image and, if necessary, the color-map to write the PNG data. 2707 * 2708 * png_image is a structure that describes the in-memory format of an image 2709 * when it is being read or defines the in-memory format of an image that you 2710 * need to write: 2711 */ 2712#if defined(PNG_SIMPLIFIED_READ_SUPPORTED) || \ 2713 defined(PNG_SIMPLIFIED_WRITE_SUPPORTED) 2714 2715#define PNG_IMAGE_VERSION 1 2716 2717typedef struct png_control *png_controlp; 2718typedef struct 2719{ 2720 png_controlp opaque; /* Initialize to NULL, free with png_image_free */ 2721 png_uint_32 version; /* Set to PNG_IMAGE_VERSION */ 2722 png_uint_32 width; /* Image width in pixels (columns) */ 2723 png_uint_32 height; /* Image height in pixels (rows) */ 2724 png_uint_32 format; /* Image format as defined below */ 2725 png_uint_32 flags; /* A bit mask containing informational flags */ 2726 png_uint_32 colormap_entries; 2727 /* Number of entries in the color-map */ 2728 2729 /* In the event of an error or warning the following field will be set to a 2730 * non-zero value and the 'message' field will contain a '\0' terminated 2731 * string with the libpng error or warning message. If both warnings and 2732 * an error were encountered, only the error is recorded. If there 2733 * are multiple warnings, only the first one is recorded. 2734 * 2735 * The upper 30 bits of this value are reserved, the low two bits contain 2736 * a value as follows: 2737 */ 2738# define PNG_IMAGE_WARNING 1 2739# define PNG_IMAGE_ERROR 2 2740 /* 2741 * The result is a two-bit code such that a value more than 1 indicates 2742 * a failure in the API just called: 2743 * 2744 * 0 - no warning or error 2745 * 1 - warning 2746 * 2 - error 2747 * 3 - error preceded by warning 2748 */ 2749# define PNG_IMAGE_FAILED(png_cntrl) ((((png_cntrl).warning_or_error)&0x03)>1) 2750 2751 png_uint_32 warning_or_error; 2752 2753 char message[64]; 2754} png_image, *png_imagep; 2755 2756/* The samples of the image have one to four channels whose components have 2757 * original values in the range 0 to 1.0: 2758 * 2759 * 1: A single gray or luminance channel (G). 2760 * 2: A gray/luminance channel and an alpha channel (GA). 2761 * 3: Three red, green, blue color channels (RGB). 2762 * 4: Three color channels and an alpha channel (RGBA). 2763 * 2764 * The components are encoded in one of two ways: 2765 * 2766 * a) As a small integer, value 0..255, contained in a single byte. For the 2767 * alpha channel the original value is simply value/255. For the color or 2768 * luminance channels the value is encoded according to the sRGB specification 2769 * and matches the 8-bit format expected by typical display devices. 2770 * 2771 * The color/gray channels are not scaled (pre-multiplied) by the alpha 2772 * channel and are suitable for passing to color management software. 2773 * 2774 * b) As a value in the range 0..65535, contained in a 2-byte integer. All 2775 * channels can be converted to the original value by dividing by 65535; all 2776 * channels are linear. Color channels use the RGB encoding (RGB end-points) of 2777 * the sRGB specification. This encoding is identified by the 2778 * PNG_FORMAT_FLAG_LINEAR flag below. 2779 * 2780 * When the simplified API needs to convert between sRGB and linear colorspaces, 2781 * the actual sRGB transfer curve defined in the sRGB specification (see the 2782 * article at http://en.wikipedia.org/wiki/SRGB) is used, not the gamma=1/2.2 2783 * approximation used elsewhere in libpng. 2784 * 2785 * When an alpha channel is present it is expected to denote pixel coverage 2786 * of the color or luminance channels and is returned as an associated alpha 2787 * channel: the color/gray channels are scaled (pre-multiplied) by the alpha 2788 * value. 2789 * 2790 * The samples are either contained directly in the image data, between 1 and 8 2791 * bytes per pixel according to the encoding, or are held in a color-map indexed 2792 * by bytes in the image data. In the case of a color-map the color-map entries 2793 * are individual samples, encoded as above, and the image data has one byte per 2794 * pixel to select the relevant sample from the color-map. 2795 */ 2796 2797/* PNG_FORMAT_* 2798 * 2799 * #defines to be used in png_image::format. Each #define identifies a 2800 * particular layout of sample data and, if present, alpha values. There are 2801 * separate defines for each of the two component encodings. 2802 * 2803 * A format is built up using single bit flag values. All combinations are 2804 * valid. Formats can be built up from the flag values or you can use one of 2805 * the predefined values below. When testing formats always use the FORMAT_FLAG 2806 * macros to test for individual features - future versions of the library may 2807 * add new flags. 2808 * 2809 * When reading or writing color-mapped images the format should be set to the 2810 * format of the entries in the color-map then png_image_{read,write}_colormap 2811 * called to read or write the color-map and set the format correctly for the 2812 * image data. Do not set the PNG_FORMAT_FLAG_COLORMAP bit directly! 2813 * 2814 * NOTE: libpng can be built with particular features disabled. If you see 2815 * compiler errors because the definition of one of the following flags has been 2816 * compiled out it is because libpng does not have the required support. It is 2817 * possible, however, for the libpng configuration to enable the format on just 2818 * read or just write; in that case you may see an error at run time. You can 2819 * guard against this by checking for the definition of the appropriate 2820 * "_SUPPORTED" macro, one of: 2821 * 2822 * PNG_SIMPLIFIED_{READ,WRITE}_{BGR,AFIRST}_SUPPORTED 2823 */ 2824#define PNG_FORMAT_FLAG_ALPHA 0x01U /* format with an alpha channel */ 2825#define PNG_FORMAT_FLAG_COLOR 0x02U /* color format: otherwise grayscale */ 2826#define PNG_FORMAT_FLAG_LINEAR 0x04U /* 2-byte channels else 1-byte */ 2827#define PNG_FORMAT_FLAG_COLORMAP 0x08U /* image data is color-mapped */ 2828 2829#ifdef PNG_FORMAT_BGR_SUPPORTED 2830# define PNG_FORMAT_FLAG_BGR 0x10U /* BGR colors, else order is RGB */ 2831#endif 2832 2833#ifdef PNG_FORMAT_AFIRST_SUPPORTED 2834# define PNG_FORMAT_FLAG_AFIRST 0x20U /* alpha channel comes first */ 2835#endif 2836 2837/* Commonly used formats have predefined macros. 2838 * 2839 * First the single byte (sRGB) formats: 2840 */ 2841#define PNG_FORMAT_GRAY 0 2842#define PNG_FORMAT_GA PNG_FORMAT_FLAG_ALPHA 2843#define PNG_FORMAT_AG (PNG_FORMAT_GA|PNG_FORMAT_FLAG_AFIRST) 2844#define PNG_FORMAT_RGB PNG_FORMAT_FLAG_COLOR 2845#define PNG_FORMAT_BGR (PNG_FORMAT_FLAG_COLOR|PNG_FORMAT_FLAG_BGR) 2846#define PNG_FORMAT_RGBA (PNG_FORMAT_RGB|PNG_FORMAT_FLAG_ALPHA) 2847#define PNG_FORMAT_ARGB (PNG_FORMAT_RGBA|PNG_FORMAT_FLAG_AFIRST) 2848#define PNG_FORMAT_BGRA (PNG_FORMAT_BGR|PNG_FORMAT_FLAG_ALPHA) 2849#define PNG_FORMAT_ABGR (PNG_FORMAT_BGRA|PNG_FORMAT_FLAG_AFIRST) 2850 2851/* Then the linear 2-byte formats. When naming these "Y" is used to 2852 * indicate a luminance (gray) channel. 2853 */ 2854#define PNG_FORMAT_LINEAR_Y PNG_FORMAT_FLAG_LINEAR 2855#define PNG_FORMAT_LINEAR_Y_ALPHA (PNG_FORMAT_FLAG_LINEAR|PNG_FORMAT_FLAG_ALPHA) 2856#define PNG_FORMAT_LINEAR_RGB (PNG_FORMAT_FLAG_LINEAR|PNG_FORMAT_FLAG_COLOR) 2857#define PNG_FORMAT_LINEAR_RGB_ALPHA \ 2858 (PNG_FORMAT_FLAG_LINEAR|PNG_FORMAT_FLAG_COLOR|PNG_FORMAT_FLAG_ALPHA) 2859 2860/* With color-mapped formats the image data is one byte for each pixel, the byte 2861 * is an index into the color-map which is formatted as above. To obtain a 2862 * color-mapped format it is sufficient just to add the PNG_FOMAT_FLAG_COLORMAP 2863 * to one of the above definitions, or you can use one of the definitions below. 2864 */ 2865#define PNG_FORMAT_RGB_COLORMAP (PNG_FORMAT_RGB|PNG_FORMAT_FLAG_COLORMAP) 2866#define PNG_FORMAT_BGR_COLORMAP (PNG_FORMAT_BGR|PNG_FORMAT_FLAG_COLORMAP) 2867#define PNG_FORMAT_RGBA_COLORMAP (PNG_FORMAT_RGBA|PNG_FORMAT_FLAG_COLORMAP) 2868#define PNG_FORMAT_ARGB_COLORMAP (PNG_FORMAT_ARGB|PNG_FORMAT_FLAG_COLORMAP) 2869#define PNG_FORMAT_BGRA_COLORMAP (PNG_FORMAT_BGRA|PNG_FORMAT_FLAG_COLORMAP) 2870#define PNG_FORMAT_ABGR_COLORMAP (PNG_FORMAT_ABGR|PNG_FORMAT_FLAG_COLORMAP) 2871 2872/* PNG_IMAGE macros 2873 * 2874 * These are convenience macros to derive information from a png_image 2875 * structure. The PNG_IMAGE_SAMPLE_ macros return values appropriate to the 2876 * actual image sample values - either the entries in the color-map or the 2877 * pixels in the image. The PNG_IMAGE_PIXEL_ macros return corresponding values 2878 * for the pixels and will always return 1 for color-mapped formats. The 2879 * remaining macros return information about the rows in the image and the 2880 * complete image. 2881 * 2882 * NOTE: All the macros that take a png_image::format parameter are compile time 2883 * constants if the format parameter is, itself, a constant. Therefore these 2884 * macros can be used in array declarations and case labels where required. 2885 * Similarly the macros are also pre-processor constants (sizeof is not used) so 2886 * they can be used in #if tests. 2887 * 2888 * First the information about the samples. 2889 */ 2890#define PNG_IMAGE_SAMPLE_CHANNELS(fmt)\ 2891 (((fmt)&(PNG_FORMAT_FLAG_COLOR|PNG_FORMAT_FLAG_ALPHA))+1) 2892 /* Return the total number of channels in a given format: 1..4 */ 2893 2894#define PNG_IMAGE_SAMPLE_COMPONENT_SIZE(fmt)\ 2895 ((((fmt) & PNG_FORMAT_FLAG_LINEAR) >> 2)+1) 2896 /* Return the size in bytes of a single component of a pixel or color-map 2897 * entry (as appropriate) in the image: 1 or 2. 2898 */ 2899 2900#define PNG_IMAGE_SAMPLE_SIZE(fmt)\ 2901 (PNG_IMAGE_SAMPLE_CHANNELS(fmt) * PNG_IMAGE_SAMPLE_COMPONENT_SIZE(fmt)) 2902 /* This is the size of the sample data for one sample. If the image is 2903 * color-mapped it is the size of one color-map entry (and image pixels are 2904 * one byte in size), otherwise it is the size of one image pixel. 2905 */ 2906 2907#define PNG_IMAGE_MAXIMUM_COLORMAP_COMPONENTS(fmt)\ 2908 (PNG_IMAGE_SAMPLE_CHANNELS(fmt) * 256) 2909 /* The maximum size of the color-map required by the format expressed in a 2910 * count of components. This can be used to compile-time allocate a 2911 * color-map: 2912 * 2913 * png_uint_16 colormap[PNG_IMAGE_MAXIMUM_COLORMAP_COMPONENTS(linear_fmt)]; 2914 * 2915 * png_byte colormap[PNG_IMAGE_MAXIMUM_COLORMAP_COMPONENTS(sRGB_fmt)]; 2916 * 2917 * Alternatively use the PNG_IMAGE_COLORMAP_SIZE macro below to use the 2918 * information from one of the png_image_begin_read_ APIs and dynamically 2919 * allocate the required memory. 2920 */ 2921 2922/* Corresponding information about the pixels */ 2923#define PNG_IMAGE_PIXEL_(test,fmt)\ 2924 (((fmt)&PNG_FORMAT_FLAG_COLORMAP)?1:test(fmt)) 2925 2926#define PNG_IMAGE_PIXEL_CHANNELS(fmt)\ 2927 PNG_IMAGE_PIXEL_(PNG_IMAGE_SAMPLE_CHANNELS,fmt) 2928 /* The number of separate channels (components) in a pixel; 1 for a 2929 * color-mapped image. 2930 */ 2931 2932#define PNG_IMAGE_PIXEL_COMPONENT_SIZE(fmt)\ 2933 PNG_IMAGE_PIXEL_(PNG_IMAGE_SAMPLE_COMPONENT_SIZE,fmt) 2934 /* The size, in bytes, of each component in a pixel; 1 for a color-mapped 2935 * image. 2936 */ 2937 2938#define PNG_IMAGE_PIXEL_SIZE(fmt) PNG_IMAGE_PIXEL_(PNG_IMAGE_SAMPLE_SIZE,fmt) 2939 /* The size, in bytes, of a complete pixel; 1 for a color-mapped image. */ 2940 2941/* Information about the whole row, or whole image */ 2942#define PNG_IMAGE_ROW_STRIDE(image)\ 2943 (PNG_IMAGE_PIXEL_CHANNELS((image).format) * (image).width) 2944 /* Return the total number of components in a single row of the image; this 2945 * is the minimum 'row stride', the minimum count of components between each 2946 * row. For a color-mapped image this is the minimum number of bytes in a 2947 * row. 2948 * 2949 * WARNING: this macro overflows for some images with more than one component 2950 * and very large image widths. libpng will refuse to process an image where 2951 * this macro would overflow. 2952 */ 2953 2954#define PNG_IMAGE_BUFFER_SIZE(image, row_stride)\ 2955 (PNG_IMAGE_PIXEL_COMPONENT_SIZE((image).format)*(image).height*(row_stride)) 2956 /* Return the size, in bytes, of an image buffer given a png_image and a row 2957 * stride - the number of components to leave space for in each row. 2958 * 2959 * WARNING: this macro overflows a 32-bit integer for some large PNG images, 2960 * libpng will refuse to process an image where such an overflow would occur. 2961 */ 2962 2963#define PNG_IMAGE_SIZE(image)\ 2964 PNG_IMAGE_BUFFER_SIZE(image, PNG_IMAGE_ROW_STRIDE(image)) 2965 /* Return the size, in bytes, of the image in memory given just a png_image; 2966 * the row stride is the minimum stride required for the image. 2967 */ 2968 2969#define PNG_IMAGE_COLORMAP_SIZE(image)\ 2970 (PNG_IMAGE_SAMPLE_SIZE((image).format) * (image).colormap_entries) 2971 /* Return the size, in bytes, of the color-map of this image. If the image 2972 * format is not a color-map format this will return a size sufficient for 2973 * 256 entries in the given format; check PNG_FORMAT_FLAG_COLORMAP if 2974 * you don't want to allocate a color-map in this case. 2975 */ 2976 2977/* PNG_IMAGE_FLAG_* 2978 * 2979 * Flags containing additional information about the image are held in the 2980 * 'flags' field of png_image. 2981 */ 2982#define PNG_IMAGE_FLAG_COLORSPACE_NOT_sRGB 0x01 2983 /* This indicates the the RGB values of the in-memory bitmap do not 2984 * correspond to the red, green and blue end-points defined by sRGB. 2985 */ 2986 2987#define PNG_IMAGE_FLAG_FAST 0x02 2988 /* On write emphasise speed over compression; the resultant PNG file will be 2989 * larger but will be produced significantly faster, particular for large 2990 * images. Do not use this option for images which will be distributed, only 2991 * used it when producing intermediate files that will be read back in 2992 * repeatedly. For a typical 24-bit image the option will double the read 2993 * speed at the cost of increasing the image size by 25%, however for many 2994 * more compressible images the PNG file can be 10 times larger with only a 2995 * slight speed gain. 2996 */ 2997 2998#define PNG_IMAGE_FLAG_16BIT_sRGB 0x04 2999 /* On read if the image is a 16-bit per component image and there is no gAMA 3000 * or sRGB chunk assume that the components are sRGB encoded. Notice that 3001 * images output by the simplified API always have gamma information; setting 3002 * this flag only affects the interpretation of 16-bit images from an 3003 * external source. It is recommended that the application expose this flag 3004 * to the user; the user can normally easily recognize the difference between 3005 * linear and sRGB encoding. This flag has no effect on write - the data 3006 * passed to the write APIs must have the correct encoding (as defined 3007 * above.) 3008 * 3009 * If the flag is not set (the default) input 16-bit per component data is 3010 * assumed to be linear. 3011 * 3012 * NOTE: the flag can only be set after the png_image_begin_read_ call, 3013 * because that call initializes the 'flags' field. 3014 */ 3015 3016#ifdef PNG_SIMPLIFIED_READ_SUPPORTED 3017/* READ APIs 3018 * --------- 3019 * 3020 * The png_image passed to the read APIs must have been initialized by setting 3021 * the png_controlp field 'opaque' to NULL (or, safer, memset the whole thing.) 3022 */ 3023#ifdef PNG_STDIO_SUPPORTED 3024PNG_EXPORT(234, int, png_image_begin_read_from_file, (png_imagep image, 3025 const char *file_name)); 3026 /* The named file is opened for read and the image header is filled in 3027 * from the PNG header in the file. 3028 */ 3029 3030PNG_EXPORT(235, int, png_image_begin_read_from_stdio, (png_imagep image, 3031 FILE* file)); 3032 /* The PNG header is read from the stdio FILE object. */ 3033#endif /* STDIO */ 3034 3035PNG_EXPORT(236, int, png_image_begin_read_from_memory, (png_imagep image, 3036 png_const_voidp memory, png_size_t size)); 3037 /* The PNG header is read from the given memory buffer. */ 3038 3039PNG_EXPORT(237, int, png_image_finish_read, (png_imagep image, 3040 png_const_colorp background, void *buffer, png_int_32 row_stride, 3041 void *colormap)); 3042 /* Finish reading the image into the supplied buffer and clean up the 3043 * png_image structure. 3044 * 3045 * row_stride is the step, in byte or 2-byte units as appropriate, 3046 * between adjacent rows. A positive stride indicates that the top-most row 3047 * is first in the buffer - the normal top-down arrangement. A negative 3048 * stride indicates that the bottom-most row is first in the buffer. 3049 * 3050 * background need only be supplied if an alpha channel must be removed from 3051 * a png_byte format and the removal is to be done by compositing on a solid 3052 * color; otherwise it may be NULL and any composition will be done directly 3053 * onto the buffer. The value is an sRGB color to use for the background, 3054 * for grayscale output the green channel is used. 3055 * 3056 * background must be supplied when an alpha channel must be removed from a 3057 * single byte color-mapped output format, in other words if: 3058 * 3059 * 1) The original format from png_image_begin_read_from_* had 3060 * PNG_FORMAT_FLAG_ALPHA set. 3061 * 2) The format set by the application does not. 3062 * 3) The format set by the application has PNG_FORMAT_FLAG_COLORMAP set and 3063 * PNG_FORMAT_FLAG_LINEAR *not* set. 3064 * 3065 * For linear output removing the alpha channel is always done by compositing 3066 * on black and background is ignored. 3067 * 3068 * colormap must be supplied when PNG_FORMAT_FLAG_COLORMAP is set. It must 3069 * be at least the size (in bytes) returned by PNG_IMAGE_COLORMAP_SIZE. 3070 * image->colormap_entries will be updated to the actual number of entries 3071 * written to the colormap; this may be less than the original value. 3072 */ 3073 3074PNG_EXPORT(238, void, png_image_free, (png_imagep image)); 3075 /* Free any data allocated by libpng in image->opaque, setting the pointer to 3076 * NULL. May be called at any time after the structure is initialized. 3077 */ 3078#endif /* SIMPLIFIED_READ */ 3079 3080#ifdef PNG_SIMPLIFIED_WRITE_SUPPORTED 3081/* WRITE APIS 3082 * ---------- 3083 * For write you must initialize a png_image structure to describe the image to 3084 * be written. To do this use memset to set the whole structure to 0 then 3085 * initialize fields describing your image. 3086 * 3087 * version: must be set to PNG_IMAGE_VERSION 3088 * opaque: must be initialized to NULL 3089 * width: image width in pixels 3090 * height: image height in rows 3091 * format: the format of the data (image and color-map) you wish to write 3092 * flags: set to 0 unless one of the defined flags applies; set 3093 * PNG_IMAGE_FLAG_COLORSPACE_NOT_sRGB for color format images where the RGB 3094 * values do not correspond to the colors in sRGB. 3095 * colormap_entries: set to the number of entries in the color-map (0 to 256) 3096 */ 3097#ifdef PNG_SIMPLIFIED_WRITE_STDIO_SUPPORTED 3098PNG_EXPORT(239, int, png_image_write_to_file, (png_imagep image, 3099 const char *file, int convert_to_8bit, const void *buffer, 3100 png_int_32 row_stride, const void *colormap)); 3101 /* Write the image to the named file. */ 3102 3103PNG_EXPORT(240, int, png_image_write_to_stdio, (png_imagep image, FILE *file, 3104 int convert_to_8_bit, const void *buffer, png_int_32 row_stride, 3105 const void *colormap)); 3106 /* Write the image to the given (FILE*). */ 3107#endif /* SIMPLIFIED_WRITE_STDIO */ 3108 3109/* With all write APIs if image is in one of the linear formats with 16-bit 3110 * data then setting convert_to_8_bit will cause the output to be an 8-bit PNG 3111 * gamma encoded according to the sRGB specification, otherwise a 16-bit linear 3112 * encoded PNG file is written. 3113 * 3114 * With color-mapped data formats the colormap parameter point to a color-map 3115 * with at least image->colormap_entries encoded in the specified format. If 3116 * the format is linear the written PNG color-map will be converted to sRGB 3117 * regardless of the convert_to_8_bit flag. 3118 * 3119 * With all APIs row_stride is handled as in the read APIs - it is the spacing 3120 * from one row to the next in component sized units (1 or 2 bytes) and if 3121 * negative indicates a bottom-up row layout in the buffer. If row_stride is 3122 * zero, libpng will calculate it for you from the image width and number of 3123 * channels. 3124 * 3125 * Note that the write API does not support interlacing, sub-8-bit pixels or 3126 * most ancillary chunks. If you need to write text chunks (e.g. for copyright 3127 * notices) you need to use one of the other APIs. 3128 */ 3129 3130PNG_EXPORT(245, int, png_image_write_to_memory, (png_imagep image, void *memory, 3131 png_alloc_size_t * PNG_RESTRICT memory_bytes, int convert_to_8_bit, 3132 const void *buffer, png_int_32 row_stride, const void *colormap)); 3133 /* Write the image to the given memory buffer. The function both writes the 3134 * whole PNG data stream to *memory and updates *memory_bytes with the count 3135 * of bytes written. 3136 * 3137 * 'memory' may be NULL. In this case *memory_bytes is not read however on 3138 * success the number of bytes which would have been written will still be 3139 * stored in *memory_bytes. On failure *memory_bytes will contain 0. 3140 * 3141 * If 'memory' is not NULL it must point to memory[*memory_bytes] of 3142 * writeable memory. 3143 * 3144 * If the function returns success memory[*memory_bytes] (if 'memory' is not 3145 * NULL) contains the written PNG data. *memory_bytes will always be less 3146 * than or equal to the original value. 3147 * 3148 * If the function returns false and *memory_bytes was not changed an error 3149 * occured during write. If *memory_bytes was changed, or is not 0 if 3150 * 'memory' was NULL, the write would have succeeded but for the memory 3151 * buffer being too small. *memory_bytes contains the required number of 3152 * bytes and will be bigger that the original value. 3153 */ 3154 3155#define png_image_write_get_memory_size(image, size, convert_to_8_bit, buffer,\ 3156 row_stride, colormap)\ 3157 png_image_write_to_memory(&(image), 0, &(size), convert_to_8_bit, buffer,\ 3158 row_stride, colormap) 3159 /* Return the amount of memory in 'size' required to compress this image. 3160 * The png_image structure 'image' must be filled in as in the above 3161 * function and must not be changed before the actual write call, the buffer 3162 * and all other parameters must also be identical to that in the final 3163 * write call. The 'size' variable need not be initialized. 3164 * 3165 * NOTE: the macro returns true/false, if false is returned 'size' will be 3166 * set to zero and the write failed and probably will fail if tried again. 3167 */ 3168 3169/* You can pre-allocate the buffer by making sure it is of sufficient size 3170 * regardless of the amount of compression achieved. The buffer size will 3171 * always be bigger than the original image and it will never be filled. The 3172 * following macros are provided to assist in allocating the buffer. 3173 */ 3174#define PNG_IMAGE_DATA_SIZE(image) (PNG_IMAGE_SIZE(image)+(image).height) 3175 /* The number of uncompressed bytes in the PNG byte encoding of the image; 3176 * uncompressing the PNG IDAT data will give this number of bytes. 3177 * 3178 * NOTE: while PNG_IMAGE_SIZE cannot overflow for an image in memory this 3179 * macro can because of the extra bytes used in the PNG byte encoding. You 3180 * need to avoid this macro if your image size approaches 2^30 in width or 3181 * height. The same goes for the remainder of these macros; they all produce 3182 * bigger numbers than the actual in-memory image size. 3183 */ 3184#ifndef PNG_ZLIB_MAX_SIZE 3185# define PNG_ZLIB_MAX_SIZE(b) ((b)+(((b)+7U)>>3)+(((b)+63U)>>6)+11U) 3186 /* An upper bound on the number of compressed bytes given 'b' uncompressed 3187 * bytes. This is based on deflateBounds() in zlib; different 3188 * implementations of zlib compression may conceivably produce more data so 3189 * if your zlib implementation is not zlib itself redefine this macro 3190 * appropriately. 3191 */ 3192#endif 3193 3194#define PNG_IMAGE_COMPRESSED_SIZE_MAX(image)\ 3195 PNG_ZLIB_MAX_SIZE((png_alloc_size_t)PNG_IMAGE_DATA_SIZE(image)) 3196 /* An upper bound on the size of the data in the PNG IDAT chunks. */ 3197 3198#define PNG_IMAGE_PNG_SIZE_MAX_(image, image_size)\ 3199 ((8U/*sig*/+25U/*IHDR*/+16U/*gAMA*/+44U/*cHRM*/+12U/*IEND*/+\ 3200 (((image).format&PNG_FORMAT_FLAG_COLORMAP)?/*colormap: PLTE, tRNS*/\ 3201 12U+3U*(image).colormap_entries/*PLTE data*/+\ 3202 (((image).format&PNG_FORMAT_FLAG_ALPHA)?\ 3203 12U/*tRNS*/+(image).colormap_entries:0U):0U)+\ 3204 12U)+(12U*((image_size)/PNG_ZBUF_SIZE))/*IDAT*/+(image_size)) 3205 /* A helper for the following macro; if your compiler cannot handle the 3206 * following macro use this one with the result of 3207 * PNG_IMAGE_COMPRESSED_SIZE_MAX(image) as the second argument (most 3208 * compilers should handle this just fine.) 3209 */ 3210 3211#define PNG_IMAGE_PNG_SIZE_MAX(image)\ 3212 PNG_IMAGE_PNG_SIZE_MAX_(image, PNG_IMAGE_COMPRESSED_SIZE_MAX(image)) 3213 /* An upper bound on the total length of the PNG data stream for 'image'. 3214 * The result is of type png_alloc_size_t, on 32-bit systems this may 3215 * overflow even though PNG_IMAGE_DATA_SIZE does not overflow; the write will 3216 * run out of buffer space but return a corrected size which should work. 3217 */ 3218#endif /* SIMPLIFIED_WRITE */ 3219/******************************************************************************* 3220 * END OF SIMPLIFIED API 3221 ******************************************************************************/ 3222#endif /* SIMPLIFIED_{READ|WRITE} */ 3223 3224/******************************************************************************* 3225 * Section 6: IMPLEMENTATION OPTIONS 3226 ******************************************************************************* 3227 * 3228 * Support for arbitrary implementation-specific optimizations. The API allows 3229 * particular options to be turned on or off. 'Option' is the number of the 3230 * option and 'onoff' is 0 (off) or non-0 (on). The value returned is given 3231 * by the PNG_OPTION_ defines below. 3232 * 3233 * HARDWARE: normally hardware capabilites, such as the Intel SSE instructions, 3234 * are detected at run time, however sometimes it may be impossible 3235 * to do this in user mode, in which case it is necessary to discover 3236 * the capabilities in an OS specific way. Such capabilities are 3237 * listed here when libpng has support for them and must be turned 3238 * ON by the application if present. 3239 * 3240 * SOFTWARE: sometimes software optimizations actually result in performance 3241 * decrease on some architectures or systems, or with some sets of 3242 * PNG images. 'Software' options allow such optimizations to be 3243 * selected at run time. 3244 */ 3245#ifdef PNG_SET_OPTION_SUPPORTED 3246#ifdef PNG_ARM_NEON_API_SUPPORTED 3247# define PNG_ARM_NEON 0 /* HARDWARE: ARM Neon SIMD instructions supported */ 3248#endif 3249#define PNG_MAXIMUM_INFLATE_WINDOW 2 /* SOFTWARE: force maximum window */ 3250#define PNG_SKIP_sRGB_CHECK_PROFILE 4 /* SOFTWARE: Check ICC profile for sRGB */ 3251#ifdef PNG_MIPS_MSA_API_SUPPORTED 3252# define PNG_MIPS_MSA 6 /* HARDWARE: MIPS Msa SIMD instructions supported */ 3253#endif 3254#define PNG_IGNORE_ADLER32 8 3255#define PNG_OPTION_NEXT 10 /* Next option - numbers must be even */ 3256 3257/* Return values: NOTE: there are four values and 'off' is *not* zero */ 3258#define PNG_OPTION_UNSET 0 /* Unset - defaults to off */ 3259#define PNG_OPTION_INVALID 1 /* Option number out of range */ 3260#define PNG_OPTION_OFF 2 3261#define PNG_OPTION_ON 3 3262 3263PNG_EXPORT(244, int, png_set_option, (png_structrp png_ptr, int option, 3264 int onoff)); 3265#endif /* SET_OPTION */ 3266 3267/******************************************************************************* 3268 * END OF HARDWARE AND SOFTWARE OPTIONS 3269 ******************************************************************************/ 3270 3271/* Maintainer: Put new public prototypes here ^, in libpng.3, in project 3272 * defs, and in scripts/symbols.def. 3273 */ 3274 3275/* The last ordinal number (this is the *last* one already used; the next 3276 * one to use is one more than this.) 3277 */ 3278#ifdef PNG_EXPORT_LAST_ORDINAL 3279 PNG_EXPORT_LAST_ORDINAL(245); 3280#endif 3281 3282#ifdef __cplusplus 3283} 3284#endif 3285 3286#endif /* PNG_VERSION_INFO_ONLY */ 3287/* Do not put anything past this line */ 3288#endif /* PNG_H */ 3289