| 1 | ␍␊ |
| 2 | /* png.h - header file for PNG reference library␍␊ |
| 3 | *␍␊ |
| 4 | * libpng version 1.5.13 - September 27, 2012␍␊ |
| 5 | * Copyright (c) 1998-2012 Glenn Randers-Pehrson␍␊ |
| 6 | * (Version 0.96 Copyright (c) 1996, 1997 Andreas Dilger)␍␊ |
| 7 | * (Version 0.88 Copyright (c) 1995, 1996 Guy Eric Schalnat, Group 42, Inc.)␍␊ |
| 8 | *␍␊ |
| 9 | * This code is released under the libpng license (See LICENSE, below)␍␊ |
| 10 | *␍␊ |
| 11 | * Authors and maintainers:␍␊ |
| 12 | * libpng versions 0.71, May 1995, through 0.88, January 1996: Guy Schalnat␍␊ |
| 13 | * libpng versions 0.89c, June 1996, through 0.96, May 1997: Andreas Dilger␍␊ |
| 14 | * libpng versions 0.97, January 1998, through 1.5.13 - September 27, 2012: Glenn␍␊ |
| 15 | * See also "Contributing Authors", below.␍␊ |
| 16 | *␍␊ |
| 17 | * Note about libpng version numbers:␍␊ |
| 18 | *␍␊ |
| 19 | * Due to various miscommunications, unforeseen code incompatibilities␍␊ |
| 20 | * and occasional factors outside the authors' control, version numbering␍␊ |
| 21 | * on the library has not always been consistent and straightforward.␍␊ |
| 22 | * The following table summarizes matters since version 0.89c, which was␍␊ |
| 23 | * the first widely used release:␍␊ |
| 24 | *␍␊ |
| 25 | * source png.h png.h shared-lib␍␊ |
| 26 | * version string int version␍␊ |
| 27 | * ------- ------ ----- ----------␍␊ |
| 28 | * 0.89c "1.0 beta 3" 0.89 89 1.0.89␍␊ |
| 29 | * 0.90 "1.0 beta 4" 0.90 90 0.90 [should have been 2.0.90]␍␊ |
| 30 | * 0.95 "1.0 beta 5" 0.95 95 0.95 [should have been 2.0.95]␍␊ |
| 31 | * 0.96 "1.0 beta 6" 0.96 96 0.96 [should have been 2.0.96]␍␊ |
| 32 | * 0.97b "1.00.97 beta 7" 1.00.97 97 1.0.1 [should have been 2.0.97]␍␊ |
| 33 | * 0.97c 0.97 97 2.0.97␍␊ |
| 34 | * 0.98 0.98 98 2.0.98␍␊ |
| 35 | * 0.99 0.99 98 2.0.99␍␊ |
| 36 | * 0.99a-m 0.99 99 2.0.99␍␊ |
| 37 | * 1.00 1.00 100 2.1.0 [100 should be 10000]␍␊ |
| 38 | * 1.0.0 (from here on, the 100 2.1.0 [100 should be 10000]␍␊ |
| 39 | * 1.0.1 png.h string is 10001 2.1.0␍␊ |
| 40 | * 1.0.1a-e identical to the 10002 from here on, the shared library␍␊ |
| 41 | * 1.0.2 source version) 10002 is 2.V where V is the source code␍␊ |
| 42 | * 1.0.2a-b 10003 version, except as noted.␍␊ |
| 43 | * 1.0.3 10003␍␊ |
| 44 | * 1.0.3a-d 10004␍␊ |
| 45 | * 1.0.4 10004␍␊ |
| 46 | * 1.0.4a-f 10005␍␊ |
| 47 | * 1.0.5 (+ 2 patches) 10005␍␊ |
| 48 | * 1.0.5a-d 10006␍␊ |
| 49 | * 1.0.5e-r 10100 (not source compatible)␍␊ |
| 50 | * 1.0.5s-v 10006 (not binary compatible)␍␊ |
| 51 | * 1.0.6 (+ 3 patches) 10006 (still binary incompatible)␍␊ |
| 52 | * 1.0.6d-f 10007 (still binary incompatible)␍␊ |
| 53 | * 1.0.6g 10007␍␊ |
| 54 | * 1.0.6h 10007 10.6h (testing xy.z so-numbering)␍␊ |
| 55 | * 1.0.6i 10007 10.6i␍␊ |
| 56 | * 1.0.6j 10007 2.1.0.6j (incompatible with 1.0.0)␍␊ |
| 57 | * 1.0.7beta11-14 DLLNUM 10007 2.1.0.7beta11-14 (binary compatible)␍␊ |
| 58 | * 1.0.7beta15-18 1 10007 2.1.0.7beta15-18 (binary compatible)␍␊ |
| 59 | * 1.0.7rc1-2 1 10007 2.1.0.7rc1-2 (binary compatible)␍␊ |
| 60 | * 1.0.7 1 10007 (still compatible)␍␊ |
| 61 | * 1.0.8beta1-4 1 10008 2.1.0.8beta1-4␍␊ |
| 62 | * 1.0.8rc1 1 10008 2.1.0.8rc1␍␊ |
| 63 | * 1.0.8 1 10008 2.1.0.8␍␊ |
| 64 | * 1.0.9beta1-6 1 10009 2.1.0.9beta1-6␍␊ |
| 65 | * 1.0.9rc1 1 10009 2.1.0.9rc1␍␊ |
| 66 | * 1.0.9beta7-10 1 10009 2.1.0.9beta7-10␍␊ |
| 67 | * 1.0.9rc2 1 10009 2.1.0.9rc2␍␊ |
| 68 | * 1.0.9 1 10009 2.1.0.9␍␊ |
| 69 | * 1.0.10beta1 1 10010 2.1.0.10beta1␍␊ |
| 70 | * 1.0.10rc1 1 10010 2.1.0.10rc1␍␊ |
| 71 | * 1.0.10 1 10010 2.1.0.10␍␊ |
| 72 | * 1.0.11beta1-3 1 10011 2.1.0.11beta1-3␍␊ |
| 73 | * 1.0.11rc1 1 10011 2.1.0.11rc1␍␊ |
| 74 | * 1.0.11 1 10011 2.1.0.11␍␊ |
| 75 | * 1.0.12beta1-2 2 10012 2.1.0.12beta1-2␍␊ |
| 76 | * 1.0.12rc1 2 10012 2.1.0.12rc1␍␊ |
| 77 | * 1.0.12 2 10012 2.1.0.12␍␊ |
| 78 | * 1.1.0a-f - 10100 2.1.1.0a-f (branch abandoned)␍␊ |
| 79 | * 1.2.0beta1-2 2 10200 2.1.2.0beta1-2␍␊ |
| 80 | * 1.2.0beta3-5 3 10200 3.1.2.0beta3-5␍␊ |
| 81 | * 1.2.0rc1 3 10200 3.1.2.0rc1␍␊ |
| 82 | * 1.2.0 3 10200 3.1.2.0␍␊ |
| 83 | * 1.2.1beta1-4 3 10201 3.1.2.1beta1-4␍␊ |
| 84 | * 1.2.1rc1-2 3 10201 3.1.2.1rc1-2␍␊ |
| 85 | * 1.2.1 3 10201 3.1.2.1␍␊ |
| 86 | * 1.2.2beta1-6 12 10202 12.so.0.1.2.2beta1-6␍␊ |
| 87 | * 1.0.13beta1 10 10013 10.so.0.1.0.13beta1␍␊ |
| 88 | * 1.0.13rc1 10 10013 10.so.0.1.0.13rc1␍␊ |
| 89 | * 1.2.2rc1 12 10202 12.so.0.1.2.2rc1␍␊ |
| 90 | * 1.0.13 10 10013 10.so.0.1.0.13␍␊ |
| 91 | * 1.2.2 12 10202 12.so.0.1.2.2␍␊ |
| 92 | * 1.2.3rc1-6 12 10203 12.so.0.1.2.3rc1-6␍␊ |
| 93 | * 1.2.3 12 10203 12.so.0.1.2.3␍␊ |
| 94 | * 1.2.4beta1-3 13 10204 12.so.0.1.2.4beta1-3␍␊ |
| 95 | * 1.0.14rc1 13 10014 10.so.0.1.0.14rc1␍␊ |
| 96 | * 1.2.4rc1 13 10204 12.so.0.1.2.4rc1␍␊ |
| 97 | * 1.0.14 10 10014 10.so.0.1.0.14␍␊ |
| 98 | * 1.2.4 13 10204 12.so.0.1.2.4␍␊ |
| 99 | * 1.2.5beta1-2 13 10205 12.so.0.1.2.5beta1-2␍␊ |
| 100 | * 1.0.15rc1-3 10 10015 10.so.0.1.0.15rc1-3␍␊ |
| 101 | * 1.2.5rc1-3 13 10205 12.so.0.1.2.5rc1-3␍␊ |
| 102 | * 1.0.15 10 10015 10.so.0.1.0.15␍␊ |
| 103 | * 1.2.5 13 10205 12.so.0.1.2.5␍␊ |
| 104 | * 1.2.6beta1-4 13 10206 12.so.0.1.2.6beta1-4␍␊ |
| 105 | * 1.0.16 10 10016 10.so.0.1.0.16␍␊ |
| 106 | * 1.2.6 13 10206 12.so.0.1.2.6␍␊ |
| 107 | * 1.2.7beta1-2 13 10207 12.so.0.1.2.7beta1-2␍␊ |
| 108 | * 1.0.17rc1 10 10017 12.so.0.1.0.17rc1␍␊ |
| 109 | * 1.2.7rc1 13 10207 12.so.0.1.2.7rc1␍␊ |
| 110 | * 1.0.17 10 10017 12.so.0.1.0.17␍␊ |
| 111 | * 1.2.7 13 10207 12.so.0.1.2.7␍␊ |
| 112 | * 1.2.8beta1-5 13 10208 12.so.0.1.2.8beta1-5␍␊ |
| 113 | * 1.0.18rc1-5 10 10018 12.so.0.1.0.18rc1-5␍␊ |
| 114 | * 1.2.8rc1-5 13 10208 12.so.0.1.2.8rc1-5␍␊ |
| 115 | * 1.0.18 10 10018 12.so.0.1.0.18␍␊ |
| 116 | * 1.2.8 13 10208 12.so.0.1.2.8␍␊ |
| 117 | * 1.2.9beta1-3 13 10209 12.so.0.1.2.9beta1-3␍␊ |
| 118 | * 1.2.9beta4-11 13 10209 12.so.0.9[.0]␍␊ |
| 119 | * 1.2.9rc1 13 10209 12.so.0.9[.0]␍␊ |
| 120 | * 1.2.9 13 10209 12.so.0.9[.0]␍␊ |
| 121 | * 1.2.10beta1-7 13 10210 12.so.0.10[.0]␍␊ |
| 122 | * 1.2.10rc1-2 13 10210 12.so.0.10[.0]␍␊ |
| 123 | * 1.2.10 13 10210 12.so.0.10[.0]␍␊ |
| 124 | * 1.4.0beta1-5 14 10400 14.so.0.0[.0]␍␊ |
| 125 | * 1.2.11beta1-4 13 10211 12.so.0.11[.0]␍␊ |
| 126 | * 1.4.0beta7-8 14 10400 14.so.0.0[.0]␍␊ |
| 127 | * 1.2.11 13 10211 12.so.0.11[.0]␍␊ |
| 128 | * 1.2.12 13 10212 12.so.0.12[.0]␍␊ |
| 129 | * 1.4.0beta9-14 14 10400 14.so.0.0[.0]␍␊ |
| 130 | * 1.2.13 13 10213 12.so.0.13[.0]␍␊ |
| 131 | * 1.4.0beta15-36 14 10400 14.so.0.0[.0]␍␊ |
| 132 | * 1.4.0beta37-87 14 10400 14.so.14.0[.0]␍␊ |
| 133 | * 1.4.0rc01 14 10400 14.so.14.0[.0]␍␊ |
| 134 | * 1.4.0beta88-109 14 10400 14.so.14.0[.0]␍␊ |
| 135 | * 1.4.0rc02-08 14 10400 14.so.14.0[.0]␍␊ |
| 136 | * 1.4.0 14 10400 14.so.14.0[.0]␍␊ |
| 137 | * 1.4.1beta01-03 14 10401 14.so.14.1[.0]␍␊ |
| 138 | * 1.4.1rc01 14 10401 14.so.14.1[.0]␍␊ |
| 139 | * 1.4.1beta04-12 14 10401 14.so.14.1[.0]␍␊ |
| 140 | * 1.4.1 14 10401 14.so.14.1[.0]␍␊ |
| 141 | * 1.4.2 14 10402 14.so.14.2[.0]␍␊ |
| 142 | * 1.4.3 14 10403 14.so.14.3[.0]␍␊ |
| 143 | * 1.4.4 14 10404 14.so.14.4[.0]␍␊ |
| 144 | * 1.5.0beta01-58 15 10500 15.so.15.0[.0]␍␊ |
| 145 | * 1.5.0rc01-07 15 10500 15.so.15.0[.0]␍␊ |
| 146 | * 1.5.0 15 10500 15.so.15.0[.0]␍␊ |
| 147 | * 1.5.1beta01-11 15 10501 15.so.15.1[.0]␍␊ |
| 148 | * 1.5.1rc01-02 15 10501 15.so.15.1[.0]␍␊ |
| 149 | * 1.5.1 15 10501 15.so.15.1[.0]␍␊ |
| 150 | * 1.5.2beta01-03 15 10502 15.so.15.2[.0]␍␊ |
| 151 | * 1.5.2rc01-03 15 10502 15.so.15.2[.0]␍␊ |
| 152 | * 1.5.2 15 10502 15.so.15.2[.0]␍␊ |
| 153 | * 1.5.3beta01-10 15 10503 15.so.15.3[.0]␍␊ |
| 154 | * 1.5.3rc01-02 15 10503 15.so.15.3[.0]␍␊ |
| 155 | * 1.5.3beta11 15 10503 15.so.15.3[.0]␍␊ |
| 156 | * 1.5.3 [omitted]␍␊ |
| 157 | * 1.5.4beta01-08 15 10504 15.so.15.4[.0]␍␊ |
| 158 | * 1.5.4rc01 15 10504 15.so.15.4[.0]␍␊ |
| 159 | * 1.5.4 15 10504 15.so.15.4[.0]␍␊ |
| 160 | * 1.5.5beta01-08 15 10505 15.so.15.5[.0]␍␊ |
| 161 | * 1.5.5rc01 15 10505 15.so.15.5[.0]␍␊ |
| 162 | * 1.5.5 15 10505 15.so.15.5[.0]␍␊ |
| 163 | * 1.5.6beta01-07 15 10506 15.so.15.6[.0]␍␊ |
| 164 | * 1.5.6rc01-03 15 10506 15.so.15.6[.0]␍␊ |
| 165 | * 1.5.6 15 10506 15.so.15.6[.0]␍␊ |
| 166 | * 1.5.7beta01-05 15 10507 15.so.15.7[.0]␍␊ |
| 167 | * 1.5.7rc01-03 15 10507 15.so.15.7[.0]␍␊ |
| 168 | * 1.5.7 15 10507 15.so.15.7[.0]␍␊ |
| 169 | * 1.5.8beta01 15 10508 15.so.15.8[.0]␍␊ |
| 170 | * 1.5.8rc01 15 10508 15.so.15.8[.0]␍␊ |
| 171 | * 1.5.8 15 10508 15.so.15.8[.0]␍␊ |
| 172 | * 1.5.9beta01-02 15 10509 15.so.15.9[.0]␍␊ |
| 173 | * 1.5.9rc01 15 10509 15.so.15.9[.0]␍␊ |
| 174 | * 1.5.9 15 10509 15.so.15.9[.0]␍␊ |
| 175 | * 1.5.10beta01-05 15 10510 15.so.15.10[.0]␍␊ |
| 176 | * 1.5.10 15 10510 15.so.15.10[.0]␍␊ |
| 177 | * 1.5.11beta01 15 10511 15.so.15.11[.0]␍␊ |
| 178 | * 1.5.11rc01-05 15 10511 15.so.15.11[.0]␍␊ |
| 179 | * 1.5.11 15 10511 15.so.15.11[.0]␍␊ |
| 180 | * 1.5.12 15 10512 15.so.15.12[.0]␍␊ |
| 181 | * 1.5.13beta01-02 15 10513 15.so.15.13[.0]␍␊ |
| 182 | * 1.5.13rc01 15 10513 15.so.15.13[.0]␍␊ |
| 183 | * 1.5.13 15 10513 15.so.15.13[.0]␍␊ |
| 184 | *␍␊ |
| 185 | * Henceforth the source version will match the shared-library major␍␊ |
| 186 | * and minor numbers; the shared-library major version number will be␍␊ |
| 187 | * used for changes in backward compatibility, as it is intended. The␍␊ |
| 188 | * PNG_LIBPNG_VER macro, which is not used within libpng but is available␍␊ |
| 189 | * for applications, is an unsigned integer of the form xyyzz corresponding␍␊ |
| 190 | * to the source version x.y.z (leading zeros in y and z). Beta versions␍␊ |
| 191 | * were given the previous public release number plus a letter, until␍␊ |
| 192 | * version 1.0.6j; from then on they were given the upcoming public␍␊ |
| 193 | * release number plus "betaNN" or "rcNN".␍␊ |
| 194 | *␍␊ |
| 195 | * Binary incompatibility exists only when applications make direct access␍␊ |
| 196 | * to the info_ptr or png_ptr members through png.h, and the compiled␍␊ |
| 197 | * application is loaded with a different version of the library.␍␊ |
| 198 | *␍␊ |
| 199 | * DLLNUM will change each time there are forward or backward changes␍␊ |
| 200 | * in binary compatibility (e.g., when a new feature is added).␍␊ |
| 201 | *␍␊ |
| 202 | * See libpng-manual.txt or libpng.3 for more information. The PNG␍␊ |
| 203 | * specification is available as a W3C Recommendation and as an ISO␍␊ |
| 204 | * Specification, <http://www.w3.org/TR/2003/REC-PNG-20031110/␍␊ |
| 205 | */␍␊ |
| 206 | ␍␊ |
| 207 | /*␍␊ |
| 208 | * COPYRIGHT NOTICE, DISCLAIMER, and LICENSE:␍␊ |
| 209 | *␍␊ |
| 210 | * If you modify libpng you may insert additional notices immediately following␍␊ |
| 211 | * this sentence.␍␊ |
| 212 | *␍␊ |
| 213 | * This code is released under the libpng license.␍␊ |
| 214 | *␍␊ |
| 215 | * libpng versions 1.2.6, August 15, 2004, through 1.5.13, September 27, 2012, are␍␊ |
| 216 | * Copyright (c) 2004, 2006-2012 Glenn Randers-Pehrson, and are␍␊ |
| 217 | * distributed according to the same disclaimer and license as libpng-1.2.5␍␊ |
| 218 | * with the following individual added to the list of Contributing Authors:␍␊ |
| 219 | *␍␊ |
| 220 | * Cosmin Truta␍␊ |
| 221 | *␍␊ |
| 222 | * libpng versions 1.0.7, July 1, 2000, through 1.2.5, October 3, 2002, are␍␊ |
| 223 | * Copyright (c) 2000-2002 Glenn Randers-Pehrson, and are␍␊ |
| 224 | * distributed according to the same disclaimer and license as libpng-1.0.6␍␊ |
| 225 | * with the following individuals added to the list of Contributing Authors:␍␊ |
| 226 | *␍␊ |
| 227 | * Simon-Pierre Cadieux␍␊ |
| 228 | * Eric S. Raymond␍␊ |
| 229 | * Gilles Vollant␍␊ |
| 230 | *␍␊ |
| 231 | * and with the following additions to the disclaimer:␍␊ |
| 232 | *␍␊ |
| 233 | * There is no warranty against interference with your enjoyment of the␍␊ |
| 234 | * library or against infringement. There is no warranty that our␍␊ |
| 235 | * efforts or the library will fulfill any of your particular purposes␍␊ |
| 236 | * or needs. This library is provided with all faults, and the entire␍␊ |
| 237 | * risk of satisfactory quality, performance, accuracy, and effort is with␍␊ |
| 238 | * the user.␍␊ |
| 239 | *␍␊ |
| 240 | * libpng versions 0.97, January 1998, through 1.0.6, March 20, 2000, are␍␊ |
| 241 | * Copyright (c) 1998, 1999, 2000 Glenn Randers-Pehrson, and are␍␊ |
| 242 | * distributed according to the same disclaimer and license as libpng-0.96,␍␊ |
| 243 | * with the following individuals added to the list of Contributing Authors:␍␊ |
| 244 | *␍␊ |
| 245 | * Tom Lane␍␊ |
| 246 | * Glenn Randers-Pehrson␍␊ |
| 247 | * Willem van Schaik␍␊ |
| 248 | *␍␊ |
| 249 | * libpng versions 0.89, June 1996, through 0.96, May 1997, are␍␊ |
| 250 | * Copyright (c) 1996, 1997 Andreas Dilger␍␊ |
| 251 | * Distributed according to the same disclaimer and license as libpng-0.88,␍␊ |
| 252 | * with the following individuals added to the list of Contributing Authors:␍␊ |
| 253 | *␍␊ |
| 254 | * John Bowler␍␊ |
| 255 | * Kevin Bracey␍␊ |
| 256 | * Sam Bushell␍␊ |
| 257 | * Magnus Holmgren␍␊ |
| 258 | * Greg Roelofs␍␊ |
| 259 | * Tom Tanner␍␊ |
| 260 | *␍␊ |
| 261 | * libpng versions 0.5, May 1995, through 0.88, January 1996, are␍␊ |
| 262 | * Copyright (c) 1995, 1996 Guy Eric Schalnat, Group 42, Inc.␍␊ |
| 263 | *␍␊ |
| 264 | * For the purposes of this copyright and license, "Contributing Authors"␍␊ |
| 265 | * is defined as the following set of individuals:␍␊ |
| 266 | *␍␊ |
| 267 | * Andreas Dilger␍␊ |
| 268 | * Dave Martindale␍␊ |
| 269 | * Guy Eric Schalnat␍␊ |
| 270 | * Paul Schmidt␍␊ |
| 271 | * Tim Wegner␍␊ |
| 272 | *␍␊ |
| 273 | * The PNG Reference Library is supplied "AS IS". The Contributing Authors␍␊ |
| 274 | * and Group 42, Inc. disclaim all warranties, expressed or implied,␍␊ |
| 275 | * including, without limitation, the warranties of merchantability and of␍␊ |
| 276 | * fitness for any purpose. The Contributing Authors and Group 42, Inc.␍␊ |
| 277 | * assume no liability for direct, indirect, incidental, special, exemplary,␍␊ |
| 278 | * or consequential damages, which may result from the use of the PNG␍␊ |
| 279 | * Reference Library, even if advised of the possibility of such damage.␍␊ |
| 280 | *␍␊ |
| 281 | * Permission is hereby granted to use, copy, modify, and distribute this␍␊ |
| 282 | * source code, or portions hereof, for any purpose, without fee, subject␍␊ |
| 283 | * to the following restrictions:␍␊ |
| 284 | *␍␊ |
| 285 | * 1. The origin of this source code must not be misrepresented.␍␊ |
| 286 | *␍␊ |
| 287 | * 2. Altered versions must be plainly marked as such and must not␍␊ |
| 288 | * be misrepresented as being the original source.␍␊ |
| 289 | *␍␊ |
| 290 | * 3. This Copyright notice may not be removed or altered from␍␊ |
| 291 | * any source or altered source distribution.␍␊ |
| 292 | *␍␊ |
| 293 | * The Contributing Authors and Group 42, Inc. specifically permit, without␍␊ |
| 294 | * fee, and encourage the use of this source code as a component to␍␊ |
| 295 | * supporting the PNG file format in commercial products. If you use this␍␊ |
| 296 | * source code in a product, acknowledgment is not required but would be␍␊ |
| 297 | * appreciated.␍␊ |
| 298 | */␍␊ |
| 299 | ␍␊ |
| 300 | /*␍␊ |
| 301 | * A "png_get_copyright" function is available, for convenient use in "about"␍␊ |
| 302 | * boxes and the like:␍␊ |
| 303 | *␍␊ |
| 304 | * printf("%s", png_get_copyright(NULL));␍␊ |
| 305 | *␍␊ |
| 306 | * Also, the PNG logo (in PNG format, of course) is supplied in the␍␊ |
| 307 | * files "pngbar.png" and "pngbar.jpg (88x31) and "pngnow.png" (98x31).␍␊ |
| 308 | */␍␊ |
| 309 | ␍␊ |
| 310 | /*␍␊ |
| 311 | * Libpng is OSI Certified Open Source Software. OSI Certified is a␍␊ |
| 312 | * certification mark of the Open Source Initiative.␍␊ |
| 313 | */␍␊ |
| 314 | ␍␊ |
| 315 | /*␍␊ |
| 316 | * The contributing authors would like to thank all those who helped␍␊ |
| 317 | * with testing, bug fixes, and patience. This wouldn't have been␍␊ |
| 318 | * possible without all of you.␍␊ |
| 319 | *␍␊ |
| 320 | * Thanks to Frank J. T. Wojcik for helping with the documentation.␍␊ |
| 321 | */␍␊ |
| 322 | ␍␊ |
| 323 | /*␍␊ |
| 324 | * Y2K compliance in libpng:␍␊ |
| 325 | * =========================␍␊ |
| 326 | *␍␊ |
| 327 | * September 27, 2012␍␊ |
| 328 | *␍␊ |
| 329 | * Since the PNG Development group is an ad-hoc body, we can't make␍␊ |
| 330 | * an official declaration.␍␊ |
| 331 | *␍␊ |
| 332 | * This is your unofficial assurance that libpng from version 0.71 and␍␊ |
| 333 | * upward through 1.5.13 are Y2K compliant. It is my belief that␍␊ |
| 334 | * earlier versions were also Y2K compliant.␍␊ |
| 335 | *␍␊ |
| 336 | * Libpng only has two year fields. One is a 2-byte unsigned integer␍␊ |
| 337 | * that will hold years up to 65535. The other holds the date in text␍␊ |
| 338 | * format, and will hold years up to 9999.␍␊ |
| 339 | *␍␊ |
| 340 | * The integer is␍␊ |
| 341 | * "png_uint_16 year" in png_time_struct.␍␊ |
| 342 | *␍␊ |
| 343 | * The string is␍␊ |
| 344 | * "char time_buffer[29]" in png_struct. This will be no␍␊ |
| 345 | * longer used in libpng-1.6.0 and will be removed from libpng-1.7.0.␍␊ |
| 346 | *␍␊ |
| 347 | * There are seven time-related functions:␍␊ |
| 348 | * png.c: png_convert_to_rfc_1123() in png.c␍␊ |
| 349 | * (formerly png_convert_to_rfc_1152() in error)␍␊ |
| 350 | * png_convert_from_struct_tm() in pngwrite.c, called in pngwrite.c␍␊ |
| 351 | * png_convert_from_time_t() in pngwrite.c␍␊ |
| 352 | * png_get_tIME() in pngget.c␍␊ |
| 353 | * png_handle_tIME() in pngrutil.c, called in pngread.c␍␊ |
| 354 | * png_set_tIME() in pngset.c␍␊ |
| 355 | * png_write_tIME() in pngwutil.c, called in pngwrite.c␍␊ |
| 356 | *␍␊ |
| 357 | * All handle dates properly in a Y2K environment. The␍␊ |
| 358 | * png_convert_from_time_t() function calls gmtime() to convert from system␍␊ |
| 359 | * clock time, which returns (year - 1900), which we properly convert to␍␊ |
| 360 | * the full 4-digit year. There is a possibility that applications using␍␊ |
| 361 | * libpng are not passing 4-digit years into the png_convert_to_rfc_1123()␍␊ |
| 362 | * function, or that they are incorrectly passing only a 2-digit year␍␊ |
| 363 | * instead of "year - 1900" into the png_convert_from_struct_tm() function,␍␊ |
| 364 | * but this is not under our control. The libpng documentation has always␍␊ |
| 365 | * stated that it works with 4-digit years, and the APIs have been␍␊ |
| 366 | * documented as such.␍␊ |
| 367 | *␍␊ |
| 368 | * The tIME chunk itself is also Y2K compliant. It uses a 2-byte unsigned␍␊ |
| 369 | * integer to hold the year, and can hold years as large as 65535.␍␊ |
| 370 | *␍␊ |
| 371 | * zlib, upon which libpng depends, is also Y2K compliant. It contains␍␊ |
| 372 | * no date-related code.␍␊ |
| 373 | *␍␊ |
| 374 | * Glenn Randers-Pehrson␍␊ |
| 375 | * libpng maintainer␍␊ |
| 376 | * PNG Development Group␍␊ |
| 377 | */␍␊ |
| 378 | ␍␊ |
| 379 | #ifndef PNG_H␍␊ |
| 380 | #define PNG_H␍␊ |
| 381 | ␍␊ |
| 382 | /* This is not the place to learn how to use libpng. The file libpng-manual.txt␍␊ |
| 383 | * describes how to use libpng, and the file example.c summarizes it␍␊ |
| 384 | * with some code on which to build. This file is useful for looking␍␊ |
| 385 | * at the actual function definitions and structure components.␍␊ |
| 386 | *␍␊ |
| 387 | * If you just need to read a PNG file and don't want to read the documentation␍␊ |
| 388 | * skip to the end of this file and read the section entitled 'simplified API'.␍␊ |
| 389 | */␍␊ |
| 390 | ␍␊ |
| 391 | /* Version information for png.h - this should match the version in png.c */␍␊ |
| 392 | #define PNG_LIBPNG_VER_STRING "1.5.13"␍␊ |
| 393 | #define PNG_HEADER_VERSION_STRING \␍␊ |
| 394 | " libpng version 1.5.13 - September 27, 2012\n"␍␊ |
| 395 | ␍␊ |
| 396 | #define PNG_LIBPNG_VER_SONUM 15␍␊ |
| 397 | #define PNG_LIBPNG_VER_DLLNUM 15␍␊ |
| 398 | ␍␊ |
| 399 | /* These should match the first 3 components of PNG_LIBPNG_VER_STRING: */␍␊ |
| 400 | #define PNG_LIBPNG_VER_MAJOR 1␍␊ |
| 401 | #define PNG_LIBPNG_VER_MINOR 5␍␊ |
| 402 | #define PNG_LIBPNG_VER_RELEASE 13␍␊ |
| 403 | ␍␊ |
| 404 | /* This should match the numeric part of the final component of␍␊ |
| 405 | * PNG_LIBPNG_VER_STRING, omitting any leading zero:␍␊ |
| 406 | */␍␊ |
| 407 | ␍␊ |
| 408 | #define PNG_LIBPNG_VER_BUILD 0␍␊ |
| 409 | ␍␊ |
| 410 | /* Release Status */␍␊ |
| 411 | #define PNG_LIBPNG_BUILD_ALPHA 1␍␊ |
| 412 | #define PNG_LIBPNG_BUILD_BETA 2␍␊ |
| 413 | #define PNG_LIBPNG_BUILD_RC 3␍␊ |
| 414 | #define PNG_LIBPNG_BUILD_STABLE 4␍␊ |
| 415 | #define PNG_LIBPNG_BUILD_RELEASE_STATUS_MASK 7␍␊ |
| 416 | ␍␊ |
| 417 | /* Release-Specific Flags */␍␊ |
| 418 | #define PNG_LIBPNG_BUILD_PATCH 8 /* Can be OR'ed with␍␊ |
| 419 | PNG_LIBPNG_BUILD_STABLE only */␍␊ |
| 420 | #define PNG_LIBPNG_BUILD_PRIVATE 16 /* Cannot be OR'ed with␍␊ |
| 421 | PNG_LIBPNG_BUILD_SPECIAL */␍␊ |
| 422 | #define PNG_LIBPNG_BUILD_SPECIAL 32 /* Cannot be OR'ed with␍␊ |
| 423 | PNG_LIBPNG_BUILD_PRIVATE */␍␊ |
| 424 | ␍␊ |
| 425 | #define PNG_LIBPNG_BUILD_BASE_TYPE PNG_LIBPNG_BUILD_STABLE␍␊ |
| 426 | ␍␊ |
| 427 | /* Careful here. At one time, Guy wanted to use 082, but that would be octal.␍␊ |
| 428 | * We must not include leading zeros.␍␊ |
| 429 | * Versions 0.7 through 1.0.0 were in the range 0 to 100 here (only␍␊ |
| 430 | * version 1.0.0 was mis-numbered 100 instead of 10000). From␍␊ |
| 431 | * version 1.0.1 it's xxyyzz, where x=major, y=minor, z=release␍␊ |
| 432 | */␍␊ |
| 433 | #define PNG_LIBPNG_VER 10513 /* 1.5.13 */␍␊ |
| 434 | ␍␊ |
| 435 | /* Library configuration: these options cannot be changed after␍␊ |
| 436 | * the library has been built.␍␊ |
| 437 | */␍␊ |
| 438 | #ifndef PNGLCONF_H␍␊ |
| 439 | /* If pnglibconf.h is missing, you can␍␊ |
| 440 | * copy scripts/pnglibconf.h.prebuilt to pnglibconf.h␍␊ |
| 441 | */␍␊ |
| 442 | # include "pnglibconf.h"␍␊ |
| 443 | #endif␍␊ |
| 444 | ␍␊ |
| 445 | #ifndef PNG_VERSION_INFO_ONLY␍␊ |
| 446 | # ifndef PNG_BUILDING_SYMBOL_TABLE␍␊ |
| 447 | /*␍␊ |
| 448 | * Standard header files (not needed for the version info or while␍␊ |
| 449 | * building symbol table -- see scripts/pnglibconf.dfa)␍␊ |
| 450 | */␍␊ |
| 451 | # ifdef PNG_SETJMP_SUPPORTED␍␊ |
| 452 | # include <setjmp.h>␍␊ |
| 453 | # endif␍␊ |
| 454 | ␍␊ |
| 455 | /* Need the time information for converting tIME chunks, it␍␊ |
| 456 | * defines struct tm:␍␊ |
| 457 | */␍␊ |
| 458 | # ifdef PNG_CONVERT_tIME_SUPPORTED␍␊ |
| 459 | /* "time.h" functions are not supported on all operating systems */␍␊ |
| 460 | # include <time.h>␍␊ |
| 461 | # endif␍␊ |
| 462 | # endif␍␊ |
| 463 | ␍␊ |
| 464 | /* Machine specific configuration. */␍␊ |
| 465 | # include "pngconf.h"␍␊ |
| 466 | #endif␍␊ |
| 467 | ␍␊ |
| 468 | /*␍␊ |
| 469 | * Added at libpng-1.2.8␍␊ |
| 470 | *␍␊ |
| 471 | * Ref MSDN: Private as priority over Special␍␊ |
| 472 | * VS_FF_PRIVATEBUILD File *was not* built using standard release␍␊ |
| 473 | * procedures. If this value is given, the StringFileInfo block must␍␊ |
| 474 | * contain a PrivateBuild string.␍␊ |
| 475 | *␍␊ |
| 476 | * VS_FF_SPECIALBUILD File *was* built by the original company using␍␊ |
| 477 | * standard release procedures but is a variation of the standard␍␊ |
| 478 | * file of the same version number. If this value is given, the␍␊ |
| 479 | * StringFileInfo block must contain a SpecialBuild string.␍␊ |
| 480 | */␍␊ |
| 481 | ␍␊ |
| 482 | #ifdef PNG_USER_PRIVATEBUILD /* From pnglibconf.h */␍␊ |
| 483 | # define PNG_LIBPNG_BUILD_TYPE \␍␊ |
| 484 | (PNG_LIBPNG_BUILD_BASE_TYPE | PNG_LIBPNG_BUILD_PRIVATE)␍␊ |
| 485 | #else␍␊ |
| 486 | # ifdef PNG_LIBPNG_SPECIALBUILD␍␊ |
| 487 | # define PNG_LIBPNG_BUILD_TYPE \␍␊ |
| 488 | (PNG_LIBPNG_BUILD_BASE_TYPE | PNG_LIBPNG_BUILD_SPECIAL)␍␊ |
| 489 | # else␍␊ |
| 490 | # define PNG_LIBPNG_BUILD_TYPE (PNG_LIBPNG_BUILD_BASE_TYPE)␍␊ |
| 491 | # endif␍␊ |
| 492 | #endif␍␊ |
| 493 | ␍␊ |
| 494 | #ifndef PNG_VERSION_INFO_ONLY␍␊ |
| 495 | ␍␊ |
| 496 | /* Inhibit C++ name-mangling for libpng functions but not for system calls. */␍␊ |
| 497 | #ifdef __cplusplus␍␊ |
| 498 | extern "C" {␍␊ |
| 499 | #endif /* __cplusplus */␍␊ |
| 500 | ␍␊ |
| 501 | /* Version information for C files, stored in png.c. This had better match␍␊ |
| 502 | * the version above.␍␊ |
| 503 | */␍␊ |
| 504 | #define png_libpng_ver png_get_header_ver(NULL)␍␊ |
| 505 | ␍␊ |
| 506 | /* This file is arranged in several sections:␍␊ |
| 507 | *␍␊ |
| 508 | * 1. Any configuration options that can be specified by for the application␍␊ |
| 509 | * code when it is built. (Build time configuration is in pnglibconf.h)␍␊ |
| 510 | * 2. Type definitions (base types are defined in pngconf.h), structure␍␊ |
| 511 | * definitions.␍␊ |
| 512 | * 3. Exported library functions.␍␊ |
| 513 | *␍␊ |
| 514 | * The library source code has additional files (principally pngpriv.h) that␍␊ |
| 515 | * allow configuration of the library.␍␊ |
| 516 | */␍␊ |
| 517 | /* Section 1: run time configuration␍␊ |
| 518 | * See pnglibconf.h for build time configuration␍␊ |
| 519 | *␍␊ |
| 520 | * Run time configuration allows the application to choose between␍␊ |
| 521 | * implementations of certain arithmetic APIs. The default is set␍␊ |
| 522 | * at build time and recorded in pnglibconf.h, but it is safe to␍␊ |
| 523 | * override these (and only these) settings. Note that this won't␍␊ |
| 524 | * change what the library does, only application code, and the␍␊ |
| 525 | * settings can (and probably should) be made on a per-file basis␍␊ |
| 526 | * by setting the #defines before including png.h␍␊ |
| 527 | *␍␊ |
| 528 | * Use macros to read integers from PNG data or use the exported␍␊ |
| 529 | * functions?␍␊ |
| 530 | * PNG_USE_READ_MACROS: use the macros (see below) Note that␍␊ |
| 531 | * the macros evaluate their argument multiple times.␍␊ |
| 532 | * PNG_NO_USE_READ_MACROS: call the relevant library function.␍␊ |
| 533 | *␍␊ |
| 534 | * Use the alternative algorithm for compositing alpha samples that␍␊ |
| 535 | * does not use division?␍␊ |
| 536 | * PNG_READ_COMPOSITE_NODIV_SUPPORTED: use the 'no division'␍␊ |
| 537 | * algorithm.␍␊ |
| 538 | * PNG_NO_READ_COMPOSITE_NODIV: use the 'division' algorithm.␍␊ |
| 539 | *␍␊ |
| 540 | * How to handle benign errors if PNG_ALLOW_BENIGN_ERRORS is␍␊ |
| 541 | * false?␍␊ |
| 542 | * PNG_ALLOW_BENIGN_ERRORS: map calls to the benign error␍␊ |
| 543 | * APIs to png_warning.␍␊ |
| 544 | * Otherwise the calls are mapped to png_error.␍␊ |
| 545 | */␍␊ |
| 546 | ␍␊ |
| 547 | /* Section 2: type definitions, including structures and compile time␍␊ |
| 548 | * constants.␍␊ |
| 549 | * See pngconf.h for base types that vary by machine/system␍␊ |
| 550 | */␍␊ |
| 551 | ␍␊ |
| 552 | /* This triggers a compiler error in png.c, if png.c and png.h␍␊ |
| 553 | * do not agree upon the version number.␍␊ |
| 554 | */␍␊ |
| 555 | typedef char* png_libpng_version_1_5_13;␍␊ |
| 556 | ␍␊ |
| 557 | /* Three color definitions. The order of the red, green, and blue, (and the␍␊ |
| 558 | * exact size) is not important, although the size of the fields need to␍␊ |
| 559 | * be png_byte or png_uint_16 (as defined below).␍␊ |
| 560 | */␍␊ |
| 561 | typedef struct png_color_struct␍␊ |
| 562 | {␍␊ |
| 563 | png_byte red;␍␊ |
| 564 | png_byte green;␍␊ |
| 565 | png_byte blue;␍␊ |
| 566 | } png_color;␍␊ |
| 567 | typedef png_color FAR * png_colorp;␍␊ |
| 568 | typedef PNG_CONST png_color FAR * png_const_colorp;␍␊ |
| 569 | typedef png_color FAR * FAR * png_colorpp;␍␊ |
| 570 | ␍␊ |
| 571 | typedef struct png_color_16_struct␍␊ |
| 572 | {␍␊ |
| 573 | png_byte index; /* used for palette files */␍␊ |
| 574 | png_uint_16 red; /* for use in red green blue files */␍␊ |
| 575 | png_uint_16 green;␍␊ |
| 576 | png_uint_16 blue;␍␊ |
| 577 | png_uint_16 gray; /* for use in grayscale files */␍␊ |
| 578 | } png_color_16;␍␊ |
| 579 | typedef png_color_16 FAR * png_color_16p;␍␊ |
| 580 | typedef PNG_CONST png_color_16 FAR * png_const_color_16p;␍␊ |
| 581 | typedef png_color_16 FAR * FAR * png_color_16pp;␍␊ |
| 582 | ␍␊ |
| 583 | typedef struct png_color_8_struct␍␊ |
| 584 | {␍␊ |
| 585 | png_byte red; /* for use in red green blue files */␍␊ |
| 586 | png_byte green;␍␊ |
| 587 | png_byte blue;␍␊ |
| 588 | png_byte gray; /* for use in grayscale files */␍␊ |
| 589 | png_byte alpha; /* for alpha channel files */␍␊ |
| 590 | } png_color_8;␍␊ |
| 591 | typedef png_color_8 FAR * png_color_8p;␍␊ |
| 592 | typedef PNG_CONST png_color_8 FAR * png_const_color_8p;␍␊ |
| 593 | typedef png_color_8 FAR * FAR * png_color_8pp;␍␊ |
| 594 | ␍␊ |
| 595 | /*␍␊ |
| 596 | * The following two structures are used for the in-core representation␍␊ |
| 597 | * of sPLT chunks.␍␊ |
| 598 | */␍␊ |
| 599 | typedef struct png_sPLT_entry_struct␍␊ |
| 600 | {␍␊ |
| 601 | png_uint_16 red;␍␊ |
| 602 | png_uint_16 green;␍␊ |
| 603 | png_uint_16 blue;␍␊ |
| 604 | png_uint_16 alpha;␍␊ |
| 605 | png_uint_16 frequency;␍␊ |
| 606 | } png_sPLT_entry;␍␊ |
| 607 | typedef png_sPLT_entry FAR * png_sPLT_entryp;␍␊ |
| 608 | typedef PNG_CONST png_sPLT_entry FAR * png_const_sPLT_entryp;␍␊ |
| 609 | typedef png_sPLT_entry FAR * FAR * png_sPLT_entrypp;␍␊ |
| 610 | ␍␊ |
| 611 | /* When the depth of the sPLT palette is 8 bits, the color and alpha samples␍␊ |
| 612 | * occupy the LSB of their respective members, and the MSB of each member␍␊ |
| 613 | * is zero-filled. The frequency member always occupies the full 16 bits.␍␊ |
| 614 | */␍␊ |
| 615 | ␍␊ |
| 616 | typedef struct png_sPLT_struct␍␊ |
| 617 | {␍␊ |
| 618 | png_charp name; /* palette name */␍␊ |
| 619 | png_byte depth; /* depth of palette samples */␍␊ |
| 620 | png_sPLT_entryp entries; /* palette entries */␍␊ |
| 621 | png_int_32 nentries; /* number of palette entries */␍␊ |
| 622 | } png_sPLT_t;␍␊ |
| 623 | typedef png_sPLT_t FAR * png_sPLT_tp;␍␊ |
| 624 | typedef PNG_CONST png_sPLT_t FAR * png_const_sPLT_tp;␍␊ |
| 625 | typedef png_sPLT_t FAR * FAR * png_sPLT_tpp;␍␊ |
| 626 | ␍␊ |
| 627 | #ifdef PNG_TEXT_SUPPORTED␍␊ |
| 628 | /* png_text holds the contents of a text/ztxt/itxt chunk in a PNG file,␍␊ |
| 629 | * and whether that contents is compressed or not. The "key" field␍␊ |
| 630 | * points to a regular zero-terminated C string. The "text" fields can be a␍␊ |
| 631 | * regular C string, an empty string, or a NULL pointer.␍␊ |
| 632 | * However, the structure returned by png_get_text() will always contain␍␊ |
| 633 | * the "text" field as a regular zero-terminated C string (possibly␍␊ |
| 634 | * empty), never a NULL pointer, so it can be safely used in printf() and␍␊ |
| 635 | * other string-handling functions. Note that the "itxt_length", "lang", and␍␊ |
| 636 | * "lang_key" members of the structure only exist when the library is built␍␊ |
| 637 | * with iTXt chunk support. Prior to libpng-1.4.0 the library was built by␍␊ |
| 638 | * default without iTXt support. Also note that when iTXt *is* supported,␍␊ |
| 639 | * the "lang" and "lang_key" fields contain NULL pointers when the␍␊ |
| 640 | * "compression" field contains * PNG_TEXT_COMPRESSION_NONE or␍␊ |
| 641 | * PNG_TEXT_COMPRESSION_zTXt. Note that the "compression value" is not the␍␊ |
| 642 | * same as what appears in the PNG tEXt/zTXt/iTXt chunk's "compression flag"␍␊ |
| 643 | * which is always 0 or 1, or its "compression method" which is always 0.␍␊ |
| 644 | */␍␊ |
| 645 | typedef struct png_text_struct␍␊ |
| 646 | {␍␊ |
| 647 | int compression; /* compression value:␍␊ |
| 648 | -1: tEXt, none␍␊ |
| 649 | 0: zTXt, deflate␍␊ |
| 650 | 1: iTXt, none␍␊ |
| 651 | 2: iTXt, deflate */␍␊ |
| 652 | png_charp key; /* keyword, 1-79 character description of "text" */␍␊ |
| 653 | png_charp text; /* comment, may be an empty string (ie "")␍␊ |
| 654 | or a NULL pointer */␍␊ |
| 655 | png_size_t text_length; /* length of the text string */␍␊ |
| 656 | png_size_t itxt_length; /* length of the itxt string */␍␊ |
| 657 | png_charp lang; /* language code, 0-79 characters␍␊ |
| 658 | or a NULL pointer */␍␊ |
| 659 | png_charp lang_key; /* keyword translated UTF-8 string, 0 or more␍␊ |
| 660 | chars or a NULL pointer */␍␊ |
| 661 | } png_text;␍␊ |
| 662 | typedef png_text FAR * png_textp;␍␊ |
| 663 | typedef PNG_CONST png_text FAR * png_const_textp;␍␊ |
| 664 | typedef png_text FAR * FAR * png_textpp;␍␊ |
| 665 | #endif␍␊ |
| 666 | ␍␊ |
| 667 | /* Supported compression types for text in PNG files (tEXt, and zTXt).␍␊ |
| 668 | * The values of the PNG_TEXT_COMPRESSION_ defines should NOT be changed. */␍␊ |
| 669 | #define PNG_TEXT_COMPRESSION_NONE_WR -3␍␊ |
| 670 | #define PNG_TEXT_COMPRESSION_zTXt_WR -2␍␊ |
| 671 | #define PNG_TEXT_COMPRESSION_NONE -1␍␊ |
| 672 | #define PNG_TEXT_COMPRESSION_zTXt 0␍␊ |
| 673 | #define PNG_ITXT_COMPRESSION_NONE 1␍␊ |
| 674 | #define PNG_ITXT_COMPRESSION_zTXt 2␍␊ |
| 675 | #define PNG_TEXT_COMPRESSION_LAST 3 /* Not a valid value */␍␊ |
| 676 | ␍␊ |
| 677 | /* png_time is a way to hold the time in an machine independent way.␍␊ |
| 678 | * Two conversions are provided, both from time_t and struct tm. There␍␊ |
| 679 | * is no portable way to convert to either of these structures, as far␍␊ |
| 680 | * as I know. If you know of a portable way, send it to me. As a side␍␊ |
| 681 | * note - PNG has always been Year 2000 compliant!␍␊ |
| 682 | */␍␊ |
| 683 | typedef struct png_time_struct␍␊ |
| 684 | {␍␊ |
| 685 | png_uint_16 year; /* full year, as in, 1995 */␍␊ |
| 686 | png_byte month; /* month of year, 1 - 12 */␍␊ |
| 687 | png_byte day; /* day of month, 1 - 31 */␍␊ |
| 688 | png_byte hour; /* hour of day, 0 - 23 */␍␊ |
| 689 | png_byte minute; /* minute of hour, 0 - 59 */␍␊ |
| 690 | png_byte second; /* second of minute, 0 - 60 (for leap seconds) */␍␊ |
| 691 | } png_time;␍␊ |
| 692 | typedef png_time FAR * png_timep;␍␊ |
| 693 | typedef PNG_CONST png_time FAR * png_const_timep;␍␊ |
| 694 | typedef png_time FAR * FAR * png_timepp;␍␊ |
| 695 | ␍␊ |
| 696 | #if defined(PNG_UNKNOWN_CHUNKS_SUPPORTED) || \␍␊ |
| 697 | defined(PNG_HANDLE_AS_UNKNOWN_SUPPORTED)␍␊ |
| 698 | /* png_unknown_chunk is a structure to hold queued chunks for which there is␍␊ |
| 699 | * no specific support. The idea is that we can use this to queue␍␊ |
| 700 | * up private chunks for output even though the library doesn't actually␍␊ |
| 701 | * know about their semantics.␍␊ |
| 702 | */␍␊ |
| 703 | typedef struct png_unknown_chunk_t␍␊ |
| 704 | {␍␊ |
| 705 | png_byte name[5];␍␊ |
| 706 | png_byte *data;␍␊ |
| 707 | png_size_t size;␍␊ |
| 708 | ␍␊ |
| 709 | /* libpng-using applications should NOT directly modify this byte. */␍␊ |
| 710 | png_byte location; /* mode of operation at read time */␍␊ |
| 711 | }␍␊ |
| 712 | ␍␊ |
| 713 | ␍␊ |
| 714 | png_unknown_chunk;␍␊ |
| 715 | typedef png_unknown_chunk FAR * png_unknown_chunkp;␍␊ |
| 716 | typedef PNG_CONST png_unknown_chunk FAR * png_const_unknown_chunkp;␍␊ |
| 717 | typedef png_unknown_chunk FAR * FAR * png_unknown_chunkpp;␍␊ |
| 718 | #endif␍␊ |
| 719 | ␍␊ |
| 720 | /* Values for the unknown chunk location byte */␍␊ |
| 721 | ␍␊ |
| 722 | #define PNG_HAVE_IHDR 0x01␍␊ |
| 723 | #define PNG_HAVE_PLTE 0x02␍␊ |
| 724 | #define PNG_AFTER_IDAT 0x08␍␊ |
| 725 | ␍␊ |
| 726 | /* The complete definition of png_info has, as of libpng-1.5.0,␍␊ |
| 727 | * been moved into a separate header file that is not accessible to␍␊ |
| 728 | * applications. Read libpng-manual.txt or libpng.3 for more info.␍␊ |
| 729 | */␍␊ |
| 730 | typedef struct png_info_def png_info;␍␊ |
| 731 | typedef png_info FAR * png_infop;␍␊ |
| 732 | typedef PNG_CONST png_info FAR * png_const_infop;␍␊ |
| 733 | typedef png_info FAR * FAR * png_infopp;␍␊ |
| 734 | ␍␊ |
| 735 | /* Maximum positive integer used in PNG is (2^31)-1 */␍␊ |
| 736 | #define PNG_UINT_31_MAX ((png_uint_32)0x7fffffffL)␍␊ |
| 737 | #define PNG_UINT_32_MAX ((png_uint_32)(-1))␍␊ |
| 738 | #define PNG_SIZE_MAX ((png_size_t)(-1))␍␊ |
| 739 | ␍␊ |
| 740 | /* These are constants for fixed point values encoded in the␍␊ |
| 741 | * PNG specification manner (x100000)␍␊ |
| 742 | */␍␊ |
| 743 | #define PNG_FP_1 100000␍␊ |
| 744 | #define PNG_FP_HALF 50000␍␊ |
| 745 | #define PNG_FP_MAX ((png_fixed_point)0x7fffffffL)␍␊ |
| 746 | #define PNG_FP_MIN (-PNG_FP_MAX)␍␊ |
| 747 | ␍␊ |
| 748 | /* These describe the color_type field in png_info. */␍␊ |
| 749 | /* color type masks */␍␊ |
| 750 | #define PNG_COLOR_MASK_PALETTE 1␍␊ |
| 751 | #define PNG_COLOR_MASK_COLOR 2␍␊ |
| 752 | #define PNG_COLOR_MASK_ALPHA 4␍␊ |
| 753 | ␍␊ |
| 754 | /* color types. Note that not all combinations are legal */␍␊ |
| 755 | #define PNG_COLOR_TYPE_GRAY 0␍␊ |
| 756 | #define PNG_COLOR_TYPE_PALETTE (PNG_COLOR_MASK_COLOR | PNG_COLOR_MASK_PALETTE)␍␊ |
| 757 | #define PNG_COLOR_TYPE_RGB (PNG_COLOR_MASK_COLOR)␍␊ |
| 758 | #define PNG_COLOR_TYPE_RGB_ALPHA (PNG_COLOR_MASK_COLOR | PNG_COLOR_MASK_ALPHA)␍␊ |
| 759 | #define PNG_COLOR_TYPE_GRAY_ALPHA (PNG_COLOR_MASK_ALPHA)␍␊ |
| 760 | /* aliases */␍␊ |
| 761 | #define PNG_COLOR_TYPE_RGBA PNG_COLOR_TYPE_RGB_ALPHA␍␊ |
| 762 | #define PNG_COLOR_TYPE_GA PNG_COLOR_TYPE_GRAY_ALPHA␍␊ |
| 763 | ␍␊ |
| 764 | /* This is for compression type. PNG 1.0-1.2 only define the single type. */␍␊ |
| 765 | #define PNG_COMPRESSION_TYPE_BASE 0 /* Deflate method 8, 32K window */␍␊ |
| 766 | #define PNG_COMPRESSION_TYPE_DEFAULT PNG_COMPRESSION_TYPE_BASE␍␊ |
| 767 | ␍␊ |
| 768 | /* This is for filter type. PNG 1.0-1.2 only define the single type. */␍␊ |
| 769 | #define PNG_FILTER_TYPE_BASE 0 /* Single row per-byte filtering */␍␊ |
| 770 | #define PNG_INTRAPIXEL_DIFFERENCING 64 /* Used only in MNG datastreams */␍␊ |
| 771 | #define PNG_FILTER_TYPE_DEFAULT PNG_FILTER_TYPE_BASE␍␊ |
| 772 | ␍␊ |
| 773 | /* These are for the interlacing type. These values should NOT be changed. */␍␊ |
| 774 | #define PNG_INTERLACE_NONE 0 /* Non-interlaced image */␍␊ |
| 775 | #define PNG_INTERLACE_ADAM7 1 /* Adam7 interlacing */␍␊ |
| 776 | #define PNG_INTERLACE_LAST 2 /* Not a valid value */␍␊ |
| 777 | ␍␊ |
| 778 | /* These are for the oFFs chunk. These values should NOT be changed. */␍␊ |
| 779 | #define PNG_OFFSET_PIXEL 0 /* Offset in pixels */␍␊ |
| 780 | #define PNG_OFFSET_MICROMETER 1 /* Offset in micrometers (1/10^6 meter) */␍␊ |
| 781 | #define PNG_OFFSET_LAST 2 /* Not a valid value */␍␊ |
| 782 | ␍␊ |
| 783 | /* These are for the pCAL chunk. These values should NOT be changed. */␍␊ |
| 784 | #define PNG_EQUATION_LINEAR 0 /* Linear transformation */␍␊ |
| 785 | #define PNG_EQUATION_BASE_E 1 /* Exponential base e transform */␍␊ |
| 786 | #define PNG_EQUATION_ARBITRARY 2 /* Arbitrary base exponential transform */␍␊ |
| 787 | #define PNG_EQUATION_HYPERBOLIC 3 /* Hyperbolic sine transformation */␍␊ |
| 788 | #define PNG_EQUATION_LAST 4 /* Not a valid value */␍␊ |
| 789 | ␍␊ |
| 790 | /* These are for the sCAL chunk. These values should NOT be changed. */␍␊ |
| 791 | #define PNG_SCALE_UNKNOWN 0 /* unknown unit (image scale) */␍␊ |
| 792 | #define PNG_SCALE_METER 1 /* meters per pixel */␍␊ |
| 793 | #define PNG_SCALE_RADIAN 2 /* radians per pixel */␍␊ |
| 794 | #define PNG_SCALE_LAST 3 /* Not a valid value */␍␊ |
| 795 | ␍␊ |
| 796 | /* These are for the pHYs chunk. These values should NOT be changed. */␍␊ |
| 797 | #define PNG_RESOLUTION_UNKNOWN 0 /* pixels/unknown unit (aspect ratio) */␍␊ |
| 798 | #define PNG_RESOLUTION_METER 1 /* pixels/meter */␍␊ |
| 799 | #define PNG_RESOLUTION_LAST 2 /* Not a valid value */␍␊ |
| 800 | ␍␊ |
| 801 | /* These are for the sRGB chunk. These values should NOT be changed. */␍␊ |
| 802 | #define PNG_sRGB_INTENT_PERCEPTUAL 0␍␊ |
| 803 | #define PNG_sRGB_INTENT_RELATIVE 1␍␊ |
| 804 | #define PNG_sRGB_INTENT_SATURATION 2␍␊ |
| 805 | #define PNG_sRGB_INTENT_ABSOLUTE 3␍␊ |
| 806 | #define PNG_sRGB_INTENT_LAST 4 /* Not a valid value */␍␊ |
| 807 | ␍␊ |
| 808 | /* This is for text chunks */␍␊ |
| 809 | #define PNG_KEYWORD_MAX_LENGTH 79␍␊ |
| 810 | ␍␊ |
| 811 | /* Maximum number of entries in PLTE/sPLT/tRNS arrays */␍␊ |
| 812 | #define PNG_MAX_PALETTE_LENGTH 256␍␊ |
| 813 | ␍␊ |
| 814 | /* These determine if an ancillary chunk's data has been successfully read␍␊ |
| 815 | * from the PNG header, or if the application has filled in the corresponding␍␊ |
| 816 | * data in the info_struct to be written into the output file. The values␍␊ |
| 817 | * of the PNG_INFO_<chunk> defines should NOT be changed.␍␊ |
| 818 | */␍␊ |
| 819 | #define PNG_INFO_gAMA 0x0001␍␊ |
| 820 | #define PNG_INFO_sBIT 0x0002␍␊ |
| 821 | #define PNG_INFO_cHRM 0x0004␍␊ |
| 822 | #define PNG_INFO_PLTE 0x0008␍␊ |
| 823 | #define PNG_INFO_tRNS 0x0010␍␊ |
| 824 | #define PNG_INFO_bKGD 0x0020␍␊ |
| 825 | #define PNG_INFO_hIST 0x0040␍␊ |
| 826 | #define PNG_INFO_pHYs 0x0080␍␊ |
| 827 | #define PNG_INFO_oFFs 0x0100␍␊ |
| 828 | #define PNG_INFO_tIME 0x0200␍␊ |
| 829 | #define PNG_INFO_pCAL 0x0400␍␊ |
| 830 | #define PNG_INFO_sRGB 0x0800 /* GR-P, 0.96a */␍␊ |
| 831 | #define PNG_INFO_iCCP 0x1000 /* ESR, 1.0.6 */␍␊ |
| 832 | #define PNG_INFO_sPLT 0x2000 /* ESR, 1.0.6 */␍␊ |
| 833 | #define PNG_INFO_sCAL 0x4000 /* ESR, 1.0.6 */␍␊ |
| 834 | #define PNG_INFO_IDAT 0x8000 /* ESR, 1.0.6 */␍␊ |
| 835 | ␍␊ |
| 836 | /* This is used for the transformation routines, as some of them␍␊ |
| 837 | * change these values for the row. It also should enable using␍␊ |
| 838 | * the routines for other purposes.␍␊ |
| 839 | */␍␊ |
| 840 | typedef struct png_row_info_struct␍␊ |
| 841 | {␍␊ |
| 842 | png_uint_32 width; /* width of row */␍␊ |
| 843 | png_size_t rowbytes; /* number of bytes in row */␍␊ |
| 844 | png_byte color_type; /* color type of row */␍␊ |
| 845 | png_byte bit_depth; /* bit depth of row */␍␊ |
| 846 | png_byte channels; /* number of channels (1, 2, 3, or 4) */␍␊ |
| 847 | png_byte pixel_depth; /* bits per pixel (depth * channels) */␍␊ |
| 848 | } png_row_info;␍␊ |
| 849 | ␍␊ |
| 850 | typedef png_row_info FAR * png_row_infop;␍␊ |
| 851 | typedef png_row_info FAR * FAR * png_row_infopp;␍␊ |
| 852 | ␍␊ |
| 853 | /* The complete definition of png_struct has, as of libpng-1.5.0,␍␊ |
| 854 | * been moved into a separate header file that is not accessible to␍␊ |
| 855 | * applications. Read libpng-manual.txt or libpng.3 for more info.␍␊ |
| 856 | */␍␊ |
| 857 | typedef struct png_struct_def png_struct;␍␊ |
| 858 | typedef PNG_CONST png_struct FAR * png_const_structp;␍␊ |
| 859 | typedef png_struct FAR * png_structp;␍␊ |
| 860 | ␍␊ |
| 861 | /* These are the function types for the I/O functions and for the functions␍␊ |
| 862 | * that allow the user to override the default I/O functions with his or her␍␊ |
| 863 | * own. The png_error_ptr type should match that of user-supplied warning␍␊ |
| 864 | * and error functions, while the png_rw_ptr type should match that of the␍␊ |
| 865 | * user read/write data functions. Note that the 'write' function must not␍␊ |
| 866 | * modify the buffer it is passed. The 'read' function, on the other hand, is␍␊ |
| 867 | * expected to return the read data in the buffer.␍␊ |
| 868 | */␍␊ |
| 869 | typedef PNG_CALLBACK(void, *png_error_ptr, (png_structp, png_const_charp));␍␊ |
| 870 | typedef PNG_CALLBACK(void, *png_rw_ptr, (png_structp, png_bytep, png_size_t));␍␊ |
| 871 | typedef PNG_CALLBACK(void, *png_flush_ptr, (png_structp));␍␊ |
| 872 | typedef PNG_CALLBACK(void, *png_read_status_ptr, (png_structp, png_uint_32,␍␊ |
| 873 | int));␍␊ |
| 874 | typedef PNG_CALLBACK(void, *png_write_status_ptr, (png_structp, png_uint_32,␍␊ |
| 875 | int));␍␊ |
| 876 | ␍␊ |
| 877 | #ifdef PNG_PROGRESSIVE_READ_SUPPORTED␍␊ |
| 878 | typedef PNG_CALLBACK(void, *png_progressive_info_ptr, (png_structp, png_infop));␍␊ |
| 879 | typedef PNG_CALLBACK(void, *png_progressive_end_ptr, (png_structp, png_infop));␍␊ |
| 880 | ␍␊ |
| 881 | /* The following callback receives png_uint_32 row_number, int pass for the␍␊ |
| 882 | * png_bytep data of the row. When transforming an interlaced image the␍␊ |
| 883 | * row number is the row number within the sub-image of the interlace pass, so␍␊ |
| 884 | * the value will increase to the height of the sub-image (not the full image)␍␊ |
| 885 | * then reset to 0 for the next pass.␍␊ |
| 886 | *␍␊ |
| 887 | * Use PNG_ROW_FROM_PASS_ROW(row, pass) and PNG_COL_FROM_PASS_COL(col, pass) to␍␊ |
| 888 | * find the output pixel (x,y) given an interlaced sub-image pixel␍␊ |
| 889 | * (row,col,pass). (See below for these macros.)␍␊ |
| 890 | */␍␊ |
| 891 | typedef PNG_CALLBACK(void, *png_progressive_row_ptr, (png_structp, png_bytep,␍␊ |
| 892 | png_uint_32, int));␍␊ |
| 893 | #endif␍␊ |
| 894 | ␍␊ |
| 895 | #if defined(PNG_READ_USER_TRANSFORM_SUPPORTED) || \␍␊ |
| 896 | defined(PNG_WRITE_USER_TRANSFORM_SUPPORTED)␍␊ |
| 897 | typedef PNG_CALLBACK(void, *png_user_transform_ptr, (png_structp, png_row_infop,␍␊ |
| 898 | png_bytep));␍␊ |
| 899 | #endif␍␊ |
| 900 | ␍␊ |
| 901 | #ifdef PNG_USER_CHUNKS_SUPPORTED␍␊ |
| 902 | typedef PNG_CALLBACK(int, *png_user_chunk_ptr, (png_structp,␍␊ |
| 903 | png_unknown_chunkp));␍␊ |
| 904 | #endif␍␊ |
| 905 | #ifdef PNG_UNKNOWN_CHUNKS_SUPPORTED␍␊ |
| 906 | typedef PNG_CALLBACK(void, *png_unknown_chunk_ptr, (png_structp));␍␊ |
| 907 | #endif␍␊ |
| 908 | ␍␊ |
| 909 | #ifdef PNG_SETJMP_SUPPORTED␍␊ |
| 910 | /* This must match the function definition in <setjmp.h>, and the application␍␊ |
| 911 | * must include this before png.h to obtain the definition of jmp_buf. The␍␊ |
| 912 | * function is required to be PNG_NORETURN, but this is not checked. If the␍␊ |
| 913 | * function does return the application will crash via an abort() or similar␍␊ |
| 914 | * system level call.␍␊ |
| 915 | *␍␊ |
| 916 | * If you get a warning here while building the library you may need to make␍␊ |
| 917 | * changes to ensure that pnglibconf.h records the calling convention used by␍␊ |
| 918 | * your compiler. This may be very difficult - try using a different compiler␍␊ |
| 919 | * to build the library!␍␊ |
| 920 | */␍␊ |
| 921 | PNG_FUNCTION(void, (PNGCAPI *png_longjmp_ptr), PNGARG((jmp_buf, int)), typedef);␍␊ |
| 922 | #endif␍␊ |
| 923 | ␍␊ |
| 924 | /* Transform masks for the high-level interface */␍␊ |
| 925 | #define PNG_TRANSFORM_IDENTITY 0x0000 /* read and write */␍␊ |
| 926 | #define PNG_TRANSFORM_STRIP_16 0x0001 /* read only */␍␊ |
| 927 | #define PNG_TRANSFORM_STRIP_ALPHA 0x0002 /* read only */␍␊ |
| 928 | #define PNG_TRANSFORM_PACKING 0x0004 /* read and write */␍␊ |
| 929 | #define PNG_TRANSFORM_PACKSWAP 0x0008 /* read and write */␍␊ |
| 930 | #define PNG_TRANSFORM_EXPAND 0x0010 /* read only */␍␊ |
| 931 | #define PNG_TRANSFORM_INVERT_MONO 0x0020 /* read and write */␍␊ |
| 932 | #define PNG_TRANSFORM_SHIFT 0x0040 /* read and write */␍␊ |
| 933 | #define PNG_TRANSFORM_BGR 0x0080 /* read and write */␍␊ |
| 934 | #define PNG_TRANSFORM_SWAP_ALPHA 0x0100 /* read and write */␍␊ |
| 935 | #define PNG_TRANSFORM_SWAP_ENDIAN 0x0200 /* read and write */␍␊ |
| 936 | #define PNG_TRANSFORM_INVERT_ALPHA 0x0400 /* read and write */␍␊ |
| 937 | #define PNG_TRANSFORM_STRIP_FILLER 0x0800 /* write only */␍␊ |
| 938 | /* Added to libpng-1.2.34 */␍␊ |
| 939 | #define PNG_TRANSFORM_STRIP_FILLER_BEFORE PNG_TRANSFORM_STRIP_FILLER␍␊ |
| 940 | #define PNG_TRANSFORM_STRIP_FILLER_AFTER 0x1000 /* write only */␍␊ |
| 941 | /* Added to libpng-1.4.0 */␍␊ |
| 942 | #define PNG_TRANSFORM_GRAY_TO_RGB 0x2000 /* read only */␍␊ |
| 943 | /* Added to libpng-1.5.4 */␍␊ |
| 944 | #define PNG_TRANSFORM_EXPAND_16 0x4000 /* read only */␍␊ |
| 945 | #define PNG_TRANSFORM_SCALE_16 0x8000 /* read only */␍␊ |
| 946 | ␍␊ |
| 947 | /* Flags for MNG supported features */␍␊ |
| 948 | #define PNG_FLAG_MNG_EMPTY_PLTE 0x01␍␊ |
| 949 | #define PNG_FLAG_MNG_FILTER_64 0x04␍␊ |
| 950 | #define PNG_ALL_MNG_FEATURES 0x05␍␊ |
| 951 | ␍␊ |
| 952 | /* NOTE: prior to 1.5 these functions had no 'API' style declaration,␍␊ |
| 953 | * this allowed the zlib default functions to be used on Windows␍␊ |
| 954 | * platforms. In 1.5 the zlib default malloc (which just calls malloc and␍␊ |
| 955 | * ignores the first argument) should be completely compatible with the␍␊ |
| 956 | * following.␍␊ |
| 957 | */␍␊ |
| 958 | typedef PNG_CALLBACK(png_voidp, *png_malloc_ptr, (png_structp,␍␊ |
| 959 | png_alloc_size_t));␍␊ |
| 960 | typedef PNG_CALLBACK(void, *png_free_ptr, (png_structp, png_voidp));␍␊ |
| 961 | ␍␊ |
| 962 | typedef png_struct FAR * FAR * png_structpp;␍␊ |
| 963 | ␍␊ |
| 964 | /* Section 3: exported functions␍␊ |
| 965 | * Here are the function definitions most commonly used. This is not␍␊ |
| 966 | * the place to find out how to use libpng. See libpng-manual.txt for the␍␊ |
| 967 | * full explanation, see example.c for the summary. This just provides␍␊ |
| 968 | * a simple one line description of the use of each function.␍␊ |
| 969 | *␍␊ |
| 970 | * The PNG_EXPORT() and PNG_EXPORTA() macros used below are defined in␍␊ |
| 971 | * pngconf.h and in the *.dfn files in the scripts directory.␍␊ |
| 972 | *␍␊ |
| 973 | * PNG_EXPORT(ordinal, type, name, (args));␍␊ |
| 974 | *␍␊ |
| 975 | * ordinal: ordinal that is used while building␍␊ |
| 976 | * *.def files. The ordinal value is only␍␊ |
| 977 | * relevant when preprocessing png.h with␍␊ |
| 978 | * the *.dfn files for building symbol table␍␊ |
| 979 | * entries, and are removed by pngconf.h.␍␊ |
| 980 | * type: return type of the function␍␊ |
| 981 | * name: function name␍␊ |
| 982 | * args: function arguments, with types␍␊ |
| 983 | *␍␊ |
| 984 | * When we wish to append attributes to a function prototype we use␍␊ |
| 985 | * the PNG_EXPORTA() macro instead.␍␊ |
| 986 | *␍␊ |
| 987 | * PNG_EXPORTA(ordinal, type, name, (args), attributes);␍␊ |
| 988 | *␍␊ |
| 989 | * ordinal, type, name, and args: same as in PNG_EXPORT().␍␊ |
| 990 | * attributes: function attributes␍␊ |
| 991 | */␍␊ |
| 992 | ␍␊ |
| 993 | /* Returns the version number of the library */␍␊ |
| 994 | PNG_EXPORT(1, png_uint_32, png_access_version_number, (void));␍␊ |
| 995 | ␍␊ |
| 996 | /* Tell lib we have already handled the first <num_bytes> magic bytes.␍␊ |
| 997 | * Handling more than 8 bytes from the beginning of the file is an error.␍␊ |
| 998 | */␍␊ |
| 999 | PNG_EXPORT(2, void, png_set_sig_bytes, (png_structp png_ptr, int num_bytes));␍␊ |
| 1000 | ␍␊ |
| 1001 | /* Check sig[start] through sig[start + num_to_check - 1] to see if it's a␍␊ |
| 1002 | * PNG file. Returns zero if the supplied bytes match the 8-byte PNG␍␊ |
| 1003 | * signature, and non-zero otherwise. Having num_to_check == 0 or␍␊ |
| 1004 | * start > 7 will always fail (ie return non-zero).␍␊ |
| 1005 | */␍␊ |
| 1006 | PNG_EXPORT(3, int, png_sig_cmp, (png_const_bytep sig, png_size_t start,␍␊ |
| 1007 | png_size_t num_to_check));␍␊ |
| 1008 | ␍␊ |
| 1009 | /* Simple signature checking function. This is the same as calling␍␊ |
| 1010 | * png_check_sig(sig, n) := !png_sig_cmp(sig, 0, n).␍␊ |
| 1011 | */␍␊ |
| 1012 | #define png_check_sig(sig, n) !png_sig_cmp((sig), 0, (n))␍␊ |
| 1013 | ␍␊ |
| 1014 | /* Allocate and initialize png_ptr struct for reading, and any other memory. */␍␊ |
| 1015 | PNG_EXPORTA(4, png_structp, png_create_read_struct,␍␊ |
| 1016 | (png_const_charp user_png_ver, png_voidp error_ptr,␍␊ |
| 1017 | png_error_ptr error_fn, png_error_ptr warn_fn),␍␊ |
| 1018 | PNG_ALLOCATED);␍␊ |
| 1019 | ␍␊ |
| 1020 | /* Allocate and initialize png_ptr struct for writing, and any other memory */␍␊ |
| 1021 | PNG_EXPORTA(5, png_structp, png_create_write_struct,␍␊ |
| 1022 | (png_const_charp user_png_ver, png_voidp error_ptr, png_error_ptr error_fn,␍␊ |
| 1023 | png_error_ptr warn_fn),␍␊ |
| 1024 | PNG_ALLOCATED);␍␊ |
| 1025 | ␍␊ |
| 1026 | PNG_EXPORT(6, png_size_t, png_get_compression_buffer_size,␍␊ |
| 1027 | (png_const_structp png_ptr));␍␊ |
| 1028 | ␍␊ |
| 1029 | PNG_EXPORT(7, void, png_set_compression_buffer_size, (png_structp png_ptr,␍␊ |
| 1030 | png_size_t size));␍␊ |
| 1031 | ␍␊ |
| 1032 | /* Moved from pngconf.h in 1.4.0 and modified to ensure setjmp/longjmp␍␊ |
| 1033 | * match up.␍␊ |
| 1034 | */␍␊ |
| 1035 | #ifdef PNG_SETJMP_SUPPORTED␍␊ |
| 1036 | /* This function returns the jmp_buf built in to *png_ptr. It must be␍␊ |
| 1037 | * supplied with an appropriate 'longjmp' function to use on that jmp_buf␍␊ |
| 1038 | * unless the default error function is overridden in which case NULL is␍␊ |
| 1039 | * acceptable. The size of the jmp_buf is checked against the actual size␍␊ |
| 1040 | * allocated by the library - the call will return NULL on a mismatch␍␊ |
| 1041 | * indicating an ABI mismatch.␍␊ |
| 1042 | */␍␊ |
| 1043 | PNG_EXPORT(8, jmp_buf*, png_set_longjmp_fn, (png_structp png_ptr,␍␊ |
| 1044 | png_longjmp_ptr longjmp_fn, size_t jmp_buf_size));␍␊ |
| 1045 | # define png_jmpbuf(png_ptr) \␍␊ |
| 1046 | (*png_set_longjmp_fn((png_ptr), longjmp, sizeof (jmp_buf)))␍␊ |
| 1047 | #else␍␊ |
| 1048 | # define png_jmpbuf(png_ptr) \␍␊ |
| 1049 | (LIBPNG_WAS_COMPILED_WITH__PNG_NO_SETJMP)␍␊ |
| 1050 | #endif␍␊ |
| 1051 | /* This function should be used by libpng applications in place of␍␊ |
| 1052 | * longjmp(png_ptr->jmpbuf, val). If longjmp_fn() has been set, it␍␊ |
| 1053 | * will use it; otherwise it will call PNG_ABORT(). This function was␍␊ |
| 1054 | * added in libpng-1.5.0.␍␊ |
| 1055 | */␍␊ |
| 1056 | PNG_EXPORTA(9, void, png_longjmp, (png_structp png_ptr, int val),␍␊ |
| 1057 | PNG_NORETURN);␍␊ |
| 1058 | ␍␊ |
| 1059 | #ifdef PNG_READ_SUPPORTED␍␊ |
| 1060 | /* Reset the compression stream */␍␊ |
| 1061 | PNG_EXPORT(10, int, png_reset_zstream, (png_structp png_ptr));␍␊ |
| 1062 | #endif␍␊ |
| 1063 | ␍␊ |
| 1064 | /* New functions added in libpng-1.0.2 (not enabled by default until 1.2.0) */␍␊ |
| 1065 | #ifdef PNG_USER_MEM_SUPPORTED␍␊ |
| 1066 | PNG_EXPORTA(11, png_structp, png_create_read_struct_2,␍␊ |
| 1067 | (png_const_charp user_png_ver, png_voidp error_ptr, png_error_ptr error_fn,␍␊ |
| 1068 | png_error_ptr warn_fn,␍␊ |
| 1069 | png_voidp mem_ptr, png_malloc_ptr malloc_fn, png_free_ptr free_fn),␍␊ |
| 1070 | PNG_ALLOCATED);␍␊ |
| 1071 | PNG_EXPORTA(12, png_structp, png_create_write_struct_2,␍␊ |
| 1072 | (png_const_charp user_png_ver, png_voidp error_ptr, png_error_ptr error_fn,␍␊ |
| 1073 | png_error_ptr warn_fn,␍␊ |
| 1074 | png_voidp mem_ptr, png_malloc_ptr malloc_fn, png_free_ptr free_fn),␍␊ |
| 1075 | PNG_ALLOCATED);␍␊ |
| 1076 | #endif␍␊ |
| 1077 | ␍␊ |
| 1078 | /* Write the PNG file signature. */␍␊ |
| 1079 | PNG_EXPORT(13, void, png_write_sig, (png_structp png_ptr));␍␊ |
| 1080 | ␍␊ |
| 1081 | /* Write a PNG chunk - size, type, (optional) data, CRC. */␍␊ |
| 1082 | PNG_EXPORT(14, void, png_write_chunk, (png_structp png_ptr, png_const_bytep␍␊ |
| 1083 | chunk_name, png_const_bytep data, png_size_t length));␍␊ |
| 1084 | ␍␊ |
| 1085 | /* Write the start of a PNG chunk - length and chunk name. */␍␊ |
| 1086 | PNG_EXPORT(15, void, png_write_chunk_start, (png_structp png_ptr,␍␊ |
| 1087 | png_const_bytep chunk_name, png_uint_32 length));␍␊ |
| 1088 | ␍␊ |
| 1089 | /* Write the data of a PNG chunk started with png_write_chunk_start(). */␍␊ |
| 1090 | PNG_EXPORT(16, void, png_write_chunk_data, (png_structp png_ptr,␍␊ |
| 1091 | png_const_bytep data, png_size_t length));␍␊ |
| 1092 | ␍␊ |
| 1093 | /* Finish a chunk started with png_write_chunk_start() (includes CRC). */␍␊ |
| 1094 | PNG_EXPORT(17, void, png_write_chunk_end, (png_structp png_ptr));␍␊ |
| 1095 | ␍␊ |
| 1096 | /* Allocate and initialize the info structure */␍␊ |
| 1097 | PNG_EXPORTA(18, png_infop, png_create_info_struct, (png_structp png_ptr),␍␊ |
| 1098 | PNG_ALLOCATED);␍␊ |
| 1099 | ␍␊ |
| 1100 | PNG_EXPORT(19, void, png_info_init_3, (png_infopp info_ptr,␍␊ |
| 1101 | png_size_t png_info_struct_size));␍␊ |
| 1102 | ␍␊ |
| 1103 | /* Writes all the PNG information before the image. */␍␊ |
| 1104 | PNG_EXPORT(20, void, png_write_info_before_PLTE,␍␊ |
| 1105 | (png_structp png_ptr, png_infop info_ptr));␍␊ |
| 1106 | PNG_EXPORT(21, void, png_write_info,␍␊ |
| 1107 | (png_structp png_ptr, png_infop info_ptr));␍␊ |
| 1108 | ␍␊ |
| 1109 | #ifdef PNG_SEQUENTIAL_READ_SUPPORTED␍␊ |
| 1110 | /* Read the information before the actual image data. */␍␊ |
| 1111 | PNG_EXPORT(22, void, png_read_info,␍␊ |
| 1112 | (png_structp png_ptr, png_infop info_ptr));␍␊ |
| 1113 | #endif␍␊ |
| 1114 | ␍␊ |
| 1115 | #ifdef PNG_TIME_RFC1123_SUPPORTED␍␊ |
| 1116 | PNG_EXPORT(23, png_const_charp, png_convert_to_rfc1123,␍␊ |
| 1117 | (png_structp png_ptr,␍␊ |
| 1118 | png_const_timep ptime));␍␊ |
| 1119 | #endif␍␊ |
| 1120 | ␍␊ |
| 1121 | #ifdef PNG_CONVERT_tIME_SUPPORTED␍␊ |
| 1122 | /* Convert from a struct tm to png_time */␍␊ |
| 1123 | PNG_EXPORT(24, void, png_convert_from_struct_tm, (png_timep ptime,␍␊ |
| 1124 | PNG_CONST struct tm FAR * ttime));␍␊ |
| 1125 | ␍␊ |
| 1126 | /* Convert from time_t to png_time. Uses gmtime() */␍␊ |
| 1127 | PNG_EXPORT(25, void, png_convert_from_time_t,␍␊ |
| 1128 | (png_timep ptime, time_t ttime));␍␊ |
| 1129 | #endif /* PNG_CONVERT_tIME_SUPPORTED */␍␊ |
| 1130 | ␍␊ |
| 1131 | #ifdef PNG_READ_EXPAND_SUPPORTED␍␊ |
| 1132 | /* Expand data to 24-bit RGB, or 8-bit grayscale, with alpha if available. */␍␊ |
| 1133 | PNG_EXPORT(26, void, png_set_expand, (png_structp png_ptr));␍␊ |
| 1134 | PNG_EXPORT(27, void, png_set_expand_gray_1_2_4_to_8, (png_structp png_ptr));␍␊ |
| 1135 | PNG_EXPORT(28, void, png_set_palette_to_rgb, (png_structp png_ptr));␍␊ |
| 1136 | PNG_EXPORT(29, void, png_set_tRNS_to_alpha, (png_structp png_ptr));␍␊ |
| 1137 | #endif␍␊ |
| 1138 | ␍␊ |
| 1139 | #ifdef PNG_READ_EXPAND_16_SUPPORTED␍␊ |
| 1140 | /* Expand to 16-bit channels, forces conversion of palette to RGB and expansion␍␊ |
| 1141 | * of a tRNS chunk if present.␍␊ |
| 1142 | */␍␊ |
| 1143 | PNG_EXPORT(221, void, png_set_expand_16, (png_structp png_ptr));␍␊ |
| 1144 | #endif␍␊ |
| 1145 | ␍␊ |
| 1146 | #if defined(PNG_READ_BGR_SUPPORTED) || defined(PNG_WRITE_BGR_SUPPORTED)␍␊ |
| 1147 | /* Use blue, green, red order for pixels. */␍␊ |
| 1148 | PNG_EXPORT(30, void, png_set_bgr, (png_structp png_ptr));␍␊ |
| 1149 | #endif␍␊ |
| 1150 | ␍␊ |
| 1151 | #ifdef PNG_READ_GRAY_TO_RGB_SUPPORTED␍␊ |
| 1152 | /* Expand the grayscale to 24-bit RGB if necessary. */␍␊ |
| 1153 | PNG_EXPORT(31, void, png_set_gray_to_rgb, (png_structp png_ptr));␍␊ |
| 1154 | #endif␍␊ |
| 1155 | ␍␊ |
| 1156 | #ifdef PNG_READ_RGB_TO_GRAY_SUPPORTED␍␊ |
| 1157 | /* Reduce RGB to grayscale. */␍␊ |
| 1158 | #define PNG_ERROR_ACTION_NONE 1␍␊ |
| 1159 | #define PNG_ERROR_ACTION_WARN 2␍␊ |
| 1160 | #define PNG_ERROR_ACTION_ERROR 3␍␊ |
| 1161 | #define PNG_RGB_TO_GRAY_DEFAULT (-1)/*for red/green coefficients*/␍␊ |
| 1162 | ␍␊ |
| 1163 | PNG_FP_EXPORT(32, void, png_set_rgb_to_gray, (png_structp png_ptr,␍␊ |
| 1164 | int error_action, double red, double green))␍␊ |
| 1165 | PNG_FIXED_EXPORT(33, void, png_set_rgb_to_gray_fixed, (png_structp png_ptr,␍␊ |
| 1166 | int error_action, png_fixed_point red, png_fixed_point green))␍␊ |
| 1167 | ␍␊ |
| 1168 | PNG_EXPORT(34, png_byte, png_get_rgb_to_gray_status, (png_const_structp␍␊ |
| 1169 | png_ptr));␍␊ |
| 1170 | #endif␍␊ |
| 1171 | ␍␊ |
| 1172 | #ifdef PNG_BUILD_GRAYSCALE_PALETTE_SUPPORTED␍␊ |
| 1173 | PNG_EXPORT(35, void, png_build_grayscale_palette, (int bit_depth,␍␊ |
| 1174 | png_colorp palette));␍␊ |
| 1175 | #endif␍␊ |
| 1176 | ␍␊ |
| 1177 | #ifdef PNG_READ_ALPHA_MODE_SUPPORTED␍␊ |
| 1178 | /* How the alpha channel is interpreted - this affects how the color channels of␍␊ |
| 1179 | * a PNG file are returned when an alpha channel, or tRNS chunk in a palette␍␊ |
| 1180 | * file, is present.␍␊ |
| 1181 | *␍␊ |
| 1182 | * This has no effect on the way pixels are written into a PNG output␍␊ |
| 1183 | * datastream. The color samples in a PNG datastream are never premultiplied␍␊ |
| 1184 | * with the alpha samples.␍␊ |
| 1185 | *␍␊ |
| 1186 | * The default is to return data according to the PNG specification: the alpha␍␊ |
| 1187 | * channel is a linear measure of the contribution of the pixel to the␍␊ |
| 1188 | * corresponding composited pixel. The gamma encoded color channels must be␍␊ |
| 1189 | * scaled according to the contribution and to do this it is necessary to undo␍␊ |
| 1190 | * the encoding, scale the color values, perform the composition and reencode␍␊ |
| 1191 | * the values. This is the 'PNG' mode.␍␊ |
| 1192 | *␍␊ |
| 1193 | * The alternative is to 'associate' the alpha with the color information by␍␊ |
| 1194 | * storing color channel values that have been scaled by the alpha. The␍␊ |
| 1195 | * advantage is that the color channels can be resampled (the image can be␍␊ |
| 1196 | * scaled) in this form. The disadvantage is that normal practice is to store␍␊ |
| 1197 | * linear, not (gamma) encoded, values and this requires 16-bit channels for␍␊ |
| 1198 | * still images rather than the 8-bit channels that are just about sufficient if␍␊ |
| 1199 | * gamma encoding is used. In addition all non-transparent pixel values,␍␊ |
| 1200 | * including completely opaque ones, must be gamma encoded to produce the final␍␊ |
| 1201 | * image. This is the 'STANDARD', 'ASSOCIATED' or 'PREMULTIPLIED' mode (the␍␊ |
| 1202 | * latter being the two common names for associated alpha color channels.)␍␊ |
| 1203 | *␍␊ |
| 1204 | * Since it is not necessary to perform arithmetic on opaque color values so␍␊ |
| 1205 | * long as they are not to be resampled and are in the final color space it is␍␊ |
| 1206 | * possible to optimize the handling of alpha by storing the opaque pixels in␍␊ |
| 1207 | * the PNG format (adjusted for the output color space) while storing partially␍␊ |
| 1208 | * opaque pixels in the standard, linear, format. The accuracy required for␍␊ |
| 1209 | * standard alpha composition is relatively low, because the pixels are␍␊ |
| 1210 | * isolated, therefore typically the accuracy loss in storing 8-bit linear␍␊ |
| 1211 | * values is acceptable. (This is not true if the alpha channel is used to␍␊ |
| 1212 | * simulate transparency over large areas - use 16 bits or the PNG mode in␍␊ |
| 1213 | * this case!) This is the 'OPTIMIZED' mode. For this mode a pixel is␍␊ |
| 1214 | * treated as opaque only if the alpha value is equal to the maximum value.␍␊ |
| 1215 | *␍␊ |
| 1216 | * The final choice is to gamma encode the alpha channel as well. This is␍␊ |
| 1217 | * broken because, in practice, no implementation that uses this choice␍␊ |
| 1218 | * correctly undoes the encoding before handling alpha composition. Use this␍␊ |
| 1219 | * choice only if other serious errors in the software or hardware you use␍␊ |
| 1220 | * mandate it; the typical serious error is for dark halos to appear around␍␊ |
| 1221 | * opaque areas of the composited PNG image because of arithmetic overflow.␍␊ |
| 1222 | *␍␊ |
| 1223 | * The API function png_set_alpha_mode specifies which of these choices to use␍␊ |
| 1224 | * with an enumerated 'mode' value and the gamma of the required output:␍␊ |
| 1225 | */␍␊ |
| 1226 | #define PNG_ALPHA_PNG 0 /* according to the PNG standard */␍␊ |
| 1227 | #define PNG_ALPHA_STANDARD 1 /* according to Porter/Duff */␍␊ |
| 1228 | #define PNG_ALPHA_ASSOCIATED 1 /* as above; this is the normal practice */␍␊ |
| 1229 | #define PNG_ALPHA_PREMULTIPLIED 1 /* as above */␍␊ |
| 1230 | #define PNG_ALPHA_OPTIMIZED 2 /* 'PNG' for opaque pixels, else 'STANDARD' */␍␊ |
| 1231 | #define PNG_ALPHA_BROKEN 3 /* the alpha channel is gamma encoded */␍␊ |
| 1232 | ␍␊ |
| 1233 | PNG_FP_EXPORT(227, void, png_set_alpha_mode, (png_structp png_ptr, int mode,␍␊ |
| 1234 | double output_gamma))␍␊ |
| 1235 | PNG_FIXED_EXPORT(228, void, png_set_alpha_mode_fixed, (png_structp png_ptr,␍␊ |
| 1236 | int mode, png_fixed_point output_gamma))␍␊ |
| 1237 | #endif␍␊ |
| 1238 | ␍␊ |
| 1239 | #if defined(PNG_READ_GAMMA_SUPPORTED) || defined(PNG_READ_ALPHA_MODE_SUPPORTED)␍␊ |
| 1240 | /* The output_gamma value is a screen gamma in libpng terminology: it expresses␍␊ |
| 1241 | * how to decode the output values, not how they are encoded. The values used␍␊ |
| 1242 | * correspond to the normal numbers used to describe the overall gamma of a␍␊ |
| 1243 | * computer display system; for example 2.2 for an sRGB conformant system. The␍␊ |
| 1244 | * values are scaled by 100000 in the _fixed version of the API (so 220000 for␍␊ |
| 1245 | * sRGB.)␍␊ |
| 1246 | *␍␊ |
| 1247 | * The inverse of the value is always used to provide a default for the PNG file␍␊ |
| 1248 | * encoding if it has no gAMA chunk and if png_set_gamma() has not been called␍␊ |
| 1249 | * to override the PNG gamma information.␍␊ |
| 1250 | *␍␊ |
| 1251 | * When the ALPHA_OPTIMIZED mode is selected the output gamma is used to encode␍␊ |
| 1252 | * opaque pixels however pixels with lower alpha values are not encoded,␍␊ |
| 1253 | * regardless of the output gamma setting.␍␊ |
| 1254 | *␍␊ |
| 1255 | * When the standard Porter Duff handling is requested with mode 1 the output␍␊ |
| 1256 | * encoding is set to be linear and the output_gamma value is only relevant␍␊ |
| 1257 | * as a default for input data that has no gamma information. The linear output␍␊ |
| 1258 | * encoding will be overridden if png_set_gamma() is called - the results may be␍␊ |
| 1259 | * highly unexpected!␍␊ |
| 1260 | *␍␊ |
| 1261 | * The following numbers are derived from the sRGB standard and the research␍␊ |
| 1262 | * behind it. sRGB is defined to be approximated by a PNG gAMA chunk value of␍␊ |
| 1263 | * 0.45455 (1/2.2) for PNG. The value implicitly includes any viewing␍␊ |
| 1264 | * correction required to take account of any differences in the color␍␊ |
| 1265 | * environment of the original scene and the intended display environment; the␍␊ |
| 1266 | * value expresses how to *decode* the image for display, not how the original␍␊ |
| 1267 | * data was *encoded*.␍␊ |
| 1268 | *␍␊ |
| 1269 | * sRGB provides a peg for the PNG standard by defining a viewing environment.␍␊ |
| 1270 | * sRGB itself, and earlier TV standards, actually use a more complex transform␍␊ |
| 1271 | * (a linear portion then a gamma 2.4 power law) than PNG can express. (PNG is␍␊ |
| 1272 | * limited to simple power laws.) By saying that an image for direct display on␍␊ |
| 1273 | * an sRGB conformant system should be stored with a gAMA chunk value of 45455␍␊ |
| 1274 | * (11.3.3.2 and 11.3.3.5 of the ISO PNG specification) the PNG specification␍␊ |
| 1275 | * makes it possible to derive values for other display systems and␍␊ |
| 1276 | * environments.␍␊ |
| 1277 | *␍␊ |
| 1278 | * The Mac value is deduced from the sRGB based on an assumption that the actual␍␊ |
| 1279 | * extra viewing correction used in early Mac display systems was implemented as␍␊ |
| 1280 | * a power 1.45 lookup table.␍␊ |
| 1281 | *␍␊ |
| 1282 | * Any system where a programmable lookup table is used or where the behavior of␍␊ |
| 1283 | * the final display device characteristics can be changed requires system␍␊ |
| 1284 | * specific code to obtain the current characteristic. However this can be␍␊ |
| 1285 | * difficult and most PNG gamma correction only requires an approximate value.␍␊ |
| 1286 | *␍␊ |
| 1287 | * By default, if png_set_alpha_mode() is not called, libpng assumes that all␍␊ |
| 1288 | * values are unencoded, linear, values and that the output device also has a␍␊ |
| 1289 | * linear characteristic. This is only very rarely correct - it is invariably␍␊ |
| 1290 | * better to call png_set_alpha_mode() with PNG_DEFAULT_sRGB than rely on the␍␊ |
| 1291 | * default if you don't know what the right answer is!␍␊ |
| 1292 | *␍␊ |
| 1293 | * The special value PNG_GAMMA_MAC_18 indicates an older Mac system (pre Mac OS␍␊ |
| 1294 | * 10.6) which used a correction table to implement a somewhat lower gamma on an␍␊ |
| 1295 | * otherwise sRGB system.␍␊ |
| 1296 | *␍␊ |
| 1297 | * Both these values are reserved (not simple gamma values) in order to allow␍␊ |
| 1298 | * more precise correction internally in the future.␍␊ |
| 1299 | *␍␊ |
| 1300 | * NOTE: the following values can be passed to either the fixed or floating␍␊ |
| 1301 | * point APIs, but the floating point API will also accept floating point␍␊ |
| 1302 | * values.␍␊ |
| 1303 | */␍␊ |
| 1304 | #define PNG_DEFAULT_sRGB -1 /* sRGB gamma and color space */␍␊ |
| 1305 | #define PNG_GAMMA_MAC_18 -2 /* Old Mac '1.8' gamma and color space */␍␊ |
| 1306 | #define PNG_GAMMA_sRGB 220000 /* Television standards--matches sRGB gamma */␍␊ |
| 1307 | #define PNG_GAMMA_LINEAR PNG_FP_1 /* Linear */␍␊ |
| 1308 | #endif␍␊ |
| 1309 | ␍␊ |
| 1310 | /* The following are examples of calls to png_set_alpha_mode to achieve the␍␊ |
| 1311 | * required overall gamma correction and, where necessary, alpha␍␊ |
| 1312 | * premultiplication.␍␊ |
| 1313 | *␍␊ |
| 1314 | * png_set_alpha_mode(pp, PNG_ALPHA_PNG, PNG_DEFAULT_sRGB);␍␊ |
| 1315 | * This is the default libpng handling of the alpha channel - it is not␍␊ |
| 1316 | * pre-multiplied into the color components. In addition the call states␍␊ |
| 1317 | * that the output is for a sRGB system and causes all PNG files without gAMA␍␊ |
| 1318 | * chunks to be assumed to be encoded using sRGB.␍␊ |
| 1319 | *␍␊ |
| 1320 | * png_set_alpha_mode(pp, PNG_ALPHA_PNG, PNG_GAMMA_MAC);␍␊ |
| 1321 | * In this case the output is assumed to be something like an sRGB conformant␍␊ |
| 1322 | * display preceeded by a power-law lookup table of power 1.45. This is how␍␊ |
| 1323 | * early Mac systems behaved.␍␊ |
| 1324 | *␍␊ |
| 1325 | * png_set_alpha_mode(pp, PNG_ALPHA_STANDARD, PNG_GAMMA_LINEAR);␍␊ |
| 1326 | * This is the classic Jim Blinn approach and will work in academic␍␊ |
| 1327 | * environments where everything is done by the book. It has the shortcoming␍␊ |
| 1328 | * of assuming that input PNG data with no gamma information is linear - this␍␊ |
| 1329 | * is unlikely to be correct unless the PNG files where generated locally.␍␊ |
| 1330 | * Most of the time the output precision will be so low as to show␍␊ |
| 1331 | * significant banding in dark areas of the image.␍␊ |
| 1332 | *␍␊ |
| 1333 | * png_set_expand_16(pp);␍␊ |
| 1334 | * png_set_alpha_mode(pp, PNG_ALPHA_STANDARD, PNG_DEFAULT_sRGB);␍␊ |
| 1335 | * This is a somewhat more realistic Jim Blinn inspired approach. PNG files␍␊ |
| 1336 | * are assumed to have the sRGB encoding if not marked with a gamma value and␍␊ |
| 1337 | * the output is always 16 bits per component. This permits accurate scaling␍␊ |
| 1338 | * and processing of the data. If you know that your input PNG files were␍␊ |
| 1339 | * generated locally you might need to replace PNG_DEFAULT_sRGB with the␍␊ |
| 1340 | * correct value for your system.␍␊ |
| 1341 | *␍␊ |
| 1342 | * png_set_alpha_mode(pp, PNG_ALPHA_OPTIMIZED, PNG_DEFAULT_sRGB);␍␊ |
| 1343 | * If you just need to composite the PNG image onto an existing background␍␊ |
| 1344 | * and if you control the code that does this you can use the optimization␍␊ |
| 1345 | * setting. In this case you just copy completely opaque pixels to the␍␊ |
| 1346 | * output. For pixels that are not completely transparent (you just skip␍␊ |
| 1347 | * those) you do the composition math using png_composite or png_composite_16␍␊ |
| 1348 | * below then encode the resultant 8-bit or 16-bit values to match the output␍␊ |
| 1349 | * encoding.␍␊ |
| 1350 | *␍␊ |
| 1351 | * Other cases␍␊ |
| 1352 | * If neither the PNG nor the standard linear encoding work for you because␍␊ |
| 1353 | * of the software or hardware you use then you have a big problem. The PNG␍␊ |
| 1354 | * case will probably result in halos around the image. The linear encoding␍␊ |
| 1355 | * will probably result in a washed out, too bright, image (it's actually too␍␊ |
| 1356 | * contrasty.) Try the ALPHA_OPTIMIZED mode above - this will probably␍␊ |
| 1357 | * substantially reduce the halos. Alternatively try:␍␊ |
| 1358 | *␍␊ |
| 1359 | * png_set_alpha_mode(pp, PNG_ALPHA_BROKEN, PNG_DEFAULT_sRGB);␍␊ |
| 1360 | * This option will also reduce the halos, but there will be slight dark␍␊ |
| 1361 | * halos round the opaque parts of the image where the background is light.␍␊ |
| 1362 | * In the OPTIMIZED mode the halos will be light halos where the background␍␊ |
| 1363 | * is dark. Take your pick - the halos are unavoidable unless you can get␍␊ |
| 1364 | * your hardware/software fixed! (The OPTIMIZED approach is slightly␍␊ |
| 1365 | * faster.)␍␊ |
| 1366 | *␍␊ |
| 1367 | * When the default gamma of PNG files doesn't match the output gamma.␍␊ |
| 1368 | * If you have PNG files with no gamma information png_set_alpha_mode allows␍␊ |
| 1369 | * you to provide a default gamma, but it also sets the ouput gamma to the␍␊ |
| 1370 | * matching value. If you know your PNG files have a gamma that doesn't␍␊ |
| 1371 | * match the output you can take advantage of the fact that␍␊ |
| 1372 | * png_set_alpha_mode always sets the output gamma but only sets the PNG␍␊ |
| 1373 | * default if it is not already set:␍␊ |
| 1374 | *␍␊ |
| 1375 | * png_set_alpha_mode(pp, PNG_ALPHA_PNG, PNG_DEFAULT_sRGB);␍␊ |
| 1376 | * png_set_alpha_mode(pp, PNG_ALPHA_PNG, PNG_GAMMA_MAC);␍␊ |
| 1377 | * The first call sets both the default and the output gamma values, the␍␊ |
| 1378 | * second call overrides the output gamma without changing the default. This␍␊ |
| 1379 | * is easier than achieving the same effect with png_set_gamma. You must use␍␊ |
| 1380 | * PNG_ALPHA_PNG for the first call - internal checking in png_set_alpha will␍␊ |
| 1381 | * fire if more than one call to png_set_alpha_mode and png_set_background is␍␊ |
| 1382 | * made in the same read operation, however multiple calls with PNG_ALPHA_PNG␍␊ |
| 1383 | * are ignored.␍␊ |
| 1384 | */␍␊ |
| 1385 | ␍␊ |
| 1386 | #ifdef PNG_READ_STRIP_ALPHA_SUPPORTED␍␊ |
| 1387 | PNG_EXPORT(36, void, png_set_strip_alpha, (png_structp png_ptr));␍␊ |
| 1388 | #endif␍␊ |
| 1389 | ␍␊ |
| 1390 | #if defined(PNG_READ_SWAP_ALPHA_SUPPORTED) || \␍␊ |
| 1391 | defined(PNG_WRITE_SWAP_ALPHA_SUPPORTED)␍␊ |
| 1392 | PNG_EXPORT(37, void, png_set_swap_alpha, (png_structp png_ptr));␍␊ |
| 1393 | #endif␍␊ |
| 1394 | ␍␊ |
| 1395 | #if defined(PNG_READ_INVERT_ALPHA_SUPPORTED) || \␍␊ |
| 1396 | defined(PNG_WRITE_INVERT_ALPHA_SUPPORTED)␍␊ |
| 1397 | PNG_EXPORT(38, void, png_set_invert_alpha, (png_structp png_ptr));␍␊ |
| 1398 | #endif␍␊ |
| 1399 | ␍␊ |
| 1400 | #if defined(PNG_READ_FILLER_SUPPORTED) || defined(PNG_WRITE_FILLER_SUPPORTED)␍␊ |
| 1401 | /* Add a filler byte to 8-bit Gray or 24-bit RGB images. */␍␊ |
| 1402 | PNG_EXPORT(39, void, png_set_filler, (png_structp png_ptr, png_uint_32 filler,␍␊ |
| 1403 | int flags));␍␊ |
| 1404 | /* The values of the PNG_FILLER_ defines should NOT be changed */␍␊ |
| 1405 | # define PNG_FILLER_BEFORE 0␍␊ |
| 1406 | # define PNG_FILLER_AFTER 1␍␊ |
| 1407 | /* Add an alpha byte to 8-bit Gray or 24-bit RGB images. */␍␊ |
| 1408 | PNG_EXPORT(40, void, png_set_add_alpha,␍␊ |
| 1409 | (png_structp png_ptr, png_uint_32 filler,␍␊ |
| 1410 | int flags));␍␊ |
| 1411 | #endif /* PNG_READ_FILLER_SUPPORTED || PNG_WRITE_FILLER_SUPPORTED */␍␊ |
| 1412 | ␍␊ |
| 1413 | #if defined(PNG_READ_SWAP_SUPPORTED) || defined(PNG_WRITE_SWAP_SUPPORTED)␍␊ |
| 1414 | /* Swap bytes in 16-bit depth files. */␍␊ |
| 1415 | PNG_EXPORT(41, void, png_set_swap, (png_structp png_ptr));␍␊ |
| 1416 | #endif␍␊ |
| 1417 | ␍␊ |
| 1418 | #if defined(PNG_READ_PACK_SUPPORTED) || defined(PNG_WRITE_PACK_SUPPORTED)␍␊ |
| 1419 | /* Use 1 byte per pixel in 1, 2, or 4-bit depth files. */␍␊ |
| 1420 | PNG_EXPORT(42, void, png_set_packing, (png_structp png_ptr));␍␊ |
| 1421 | #endif␍␊ |
| 1422 | ␍␊ |
| 1423 | #if defined(PNG_READ_PACKSWAP_SUPPORTED) || \␍␊ |
| 1424 | defined(PNG_WRITE_PACKSWAP_SUPPORTED)␍␊ |
| 1425 | /* Swap packing order of pixels in bytes. */␍␊ |
| 1426 | PNG_EXPORT(43, void, png_set_packswap, (png_structp png_ptr));␍␊ |
| 1427 | #endif␍␊ |
| 1428 | ␍␊ |
| 1429 | #if defined(PNG_READ_SHIFT_SUPPORTED) || defined(PNG_WRITE_SHIFT_SUPPORTED)␍␊ |
| 1430 | /* Converts files to legal bit depths. */␍␊ |
| 1431 | PNG_EXPORT(44, void, png_set_shift, (png_structp png_ptr, png_const_color_8p␍␊ |
| 1432 | true_bits));␍␊ |
| 1433 | #endif␍␊ |
| 1434 | ␍␊ |
| 1435 | #if defined(PNG_READ_INTERLACING_SUPPORTED) || \␍␊ |
| 1436 | defined(PNG_WRITE_INTERLACING_SUPPORTED)␍␊ |
| 1437 | /* Have the code handle the interlacing. Returns the number of passes.␍␊ |
| 1438 | * MUST be called before png_read_update_info or png_start_read_image,␍␊ |
| 1439 | * otherwise it will not have the desired effect. Note that it is still␍␊ |
| 1440 | * necessary to call png_read_row or png_read_rows png_get_image_height␍␊ |
| 1441 | * times for each pass.␍␊ |
| 1442 | */␍␊ |
| 1443 | PNG_EXPORT(45, int, png_set_interlace_handling, (png_structp png_ptr));␍␊ |
| 1444 | #endif␍␊ |
| 1445 | ␍␊ |
| 1446 | #if defined(PNG_READ_INVERT_SUPPORTED) || defined(PNG_WRITE_INVERT_SUPPORTED)␍␊ |
| 1447 | /* Invert monochrome files */␍␊ |
| 1448 | PNG_EXPORT(46, void, png_set_invert_mono, (png_structp png_ptr));␍␊ |
| 1449 | #endif␍␊ |
| 1450 | ␍␊ |
| 1451 | #ifdef PNG_READ_BACKGROUND_SUPPORTED␍␊ |
| 1452 | /* Handle alpha and tRNS by replacing with a background color. Prior to␍␊ |
| 1453 | * libpng-1.5.4 this API must not be called before the PNG file header has been␍␊ |
| 1454 | * read. Doing so will result in unexpected behavior and possible warnings or␍␊ |
| 1455 | * errors if the PNG file contains a bKGD chunk.␍␊ |
| 1456 | */␍␊ |
| 1457 | PNG_FP_EXPORT(47, void, png_set_background, (png_structp png_ptr,␍␊ |
| 1458 | png_const_color_16p background_color, int background_gamma_code,␍␊ |
| 1459 | int need_expand, double background_gamma))␍␊ |
| 1460 | PNG_FIXED_EXPORT(215, void, png_set_background_fixed, (png_structp png_ptr,␍␊ |
| 1461 | png_const_color_16p background_color, int background_gamma_code,␍␊ |
| 1462 | int need_expand, png_fixed_point background_gamma))␍␊ |
| 1463 | #endif␍␊ |
| 1464 | #ifdef PNG_READ_BACKGROUND_SUPPORTED␍␊ |
| 1465 | # define PNG_BACKGROUND_GAMMA_UNKNOWN 0␍␊ |
| 1466 | # define PNG_BACKGROUND_GAMMA_SCREEN 1␍␊ |
| 1467 | # define PNG_BACKGROUND_GAMMA_FILE 2␍␊ |
| 1468 | # define PNG_BACKGROUND_GAMMA_UNIQUE 3␍␊ |
| 1469 | #endif␍␊ |
| 1470 | ␍␊ |
| 1471 | #ifdef PNG_READ_SCALE_16_TO_8_SUPPORTED␍␊ |
| 1472 | /* Scale a 16-bit depth file down to 8-bit, accurately. */␍␊ |
| 1473 | PNG_EXPORT(229, void, png_set_scale_16, (png_structp png_ptr));␍␊ |
| 1474 | #endif␍␊ |
| 1475 | ␍␊ |
| 1476 | #ifdef PNG_READ_STRIP_16_TO_8_SUPPORTED␍␊ |
| 1477 | #define PNG_READ_16_TO_8 SUPPORTED /* Name prior to 1.5.4 */␍␊ |
| 1478 | /* Strip the second byte of information from a 16-bit depth file. */␍␊ |
| 1479 | PNG_EXPORT(48, void, png_set_strip_16, (png_structp png_ptr));␍␊ |
| 1480 | #endif␍␊ |
| 1481 | ␍␊ |
| 1482 | #ifdef PNG_READ_QUANTIZE_SUPPORTED␍␊ |
| 1483 | /* Turn on quantizing, and reduce the palette to the number of colors␍␊ |
| 1484 | * available.␍␊ |
| 1485 | */␍␊ |
| 1486 | PNG_EXPORT(49, void, png_set_quantize,␍␊ |
| 1487 | (png_structp png_ptr, png_colorp palette,␍␊ |
| 1488 | int num_palette, int maximum_colors, png_const_uint_16p histogram,␍␊ |
| 1489 | int full_quantize));␍␊ |
| 1490 | #endif␍␊ |
| 1491 | ␍␊ |
| 1492 | #ifdef PNG_READ_GAMMA_SUPPORTED␍␊ |
| 1493 | /* The threshold on gamma processing is configurable but hard-wired into the␍␊ |
| 1494 | * library. The following is the floating point variant.␍␊ |
| 1495 | */␍␊ |
| 1496 | #define PNG_GAMMA_THRESHOLD (PNG_GAMMA_THRESHOLD_FIXED*.00001)␍␊ |
| 1497 | ␍␊ |
| 1498 | /* Handle gamma correction. Screen_gamma=(display_exponent).␍␊ |
| 1499 | * NOTE: this API simply sets the screen and file gamma values. It will␍␊ |
| 1500 | * therefore override the value for gamma in a PNG file if it is called after␍␊ |
| 1501 | * the file header has been read - use with care - call before reading the PNG␍␊ |
| 1502 | * file for best results!␍␊ |
| 1503 | *␍␊ |
| 1504 | * These routines accept the same gamma values as png_set_alpha_mode (described␍␊ |
| 1505 | * above). The PNG_GAMMA_ defines and PNG_DEFAULT_sRGB can be passed to either␍␊ |
| 1506 | * API (floating point or fixed.) Notice, however, that the 'file_gamma' value␍␊ |
| 1507 | * is the inverse of a 'screen gamma' value.␍␊ |
| 1508 | */␍␊ |
| 1509 | PNG_FP_EXPORT(50, void, png_set_gamma,␍␊ |
| 1510 | (png_structp png_ptr, double screen_gamma,␍␊ |
| 1511 | double override_file_gamma))␍␊ |
| 1512 | PNG_FIXED_EXPORT(208, void, png_set_gamma_fixed, (png_structp png_ptr,␍␊ |
| 1513 | png_fixed_point screen_gamma, png_fixed_point override_file_gamma))␍␊ |
| 1514 | #endif␍␊ |
| 1515 | ␍␊ |
| 1516 | #ifdef PNG_WRITE_FLUSH_SUPPORTED␍␊ |
| 1517 | /* Set how many lines between output flushes - 0 for no flushing */␍␊ |
| 1518 | PNG_EXPORT(51, void, png_set_flush, (png_structp png_ptr, int nrows));␍␊ |
| 1519 | /* Flush the current PNG output buffer */␍␊ |
| 1520 | PNG_EXPORT(52, void, png_write_flush, (png_structp png_ptr));␍␊ |
| 1521 | #endif␍␊ |
| 1522 | ␍␊ |
| 1523 | /* Optional update palette with requested transformations */␍␊ |
| 1524 | PNG_EXPORT(53, void, png_start_read_image, (png_structp png_ptr));␍␊ |
| 1525 | ␍␊ |
| 1526 | /* Optional call to update the users info structure */␍␊ |
| 1527 | PNG_EXPORT(54, void, png_read_update_info,␍␊ |
| 1528 | (png_structp png_ptr, png_infop info_ptr));␍␊ |
| 1529 | ␍␊ |
| 1530 | #ifdef PNG_SEQUENTIAL_READ_SUPPORTED␍␊ |
| 1531 | /* Read one or more rows of image data. */␍␊ |
| 1532 | PNG_EXPORT(55, void, png_read_rows, (png_structp png_ptr, png_bytepp row,␍␊ |
| 1533 | png_bytepp display_row, png_uint_32 num_rows));␍␊ |
| 1534 | #endif␍␊ |
| 1535 | ␍␊ |
| 1536 | #ifdef PNG_SEQUENTIAL_READ_SUPPORTED␍␊ |
| 1537 | /* Read a row of data. */␍␊ |
| 1538 | PNG_EXPORT(56, void, png_read_row, (png_structp png_ptr, png_bytep row,␍␊ |
| 1539 | png_bytep display_row));␍␊ |
| 1540 | #endif␍␊ |
| 1541 | ␍␊ |
| 1542 | #ifdef PNG_SEQUENTIAL_READ_SUPPORTED␍␊ |
| 1543 | /* Read the whole image into memory at once. */␍␊ |
| 1544 | PNG_EXPORT(57, void, png_read_image, (png_structp png_ptr, png_bytepp image));␍␊ |
| 1545 | #endif␍␊ |
| 1546 | ␍␊ |
| 1547 | /* Write a row of image data */␍␊ |
| 1548 | PNG_EXPORT(58, void, png_write_row,␍␊ |
| 1549 | (png_structp png_ptr, png_const_bytep row));␍␊ |
| 1550 | ␍␊ |
| 1551 | /* Write a few rows of image data: (*row) is not written; however, the type␍␊ |
| 1552 | * is declared as writeable to maintain compatibility with previous versions␍␊ |
| 1553 | * of libpng and to allow the 'display_row' array from read_rows to be passed␍␊ |
| 1554 | * unchanged to write_rows.␍␊ |
| 1555 | */␍␊ |
| 1556 | PNG_EXPORT(59, void, png_write_rows, (png_structp png_ptr, png_bytepp row,␍␊ |
| 1557 | png_uint_32 num_rows));␍␊ |
| 1558 | ␍␊ |
| 1559 | /* Write the image data */␍␊ |
| 1560 | PNG_EXPORT(60, void, png_write_image,␍␊ |
| 1561 | (png_structp png_ptr, png_bytepp image));␍␊ |
| 1562 | ␍␊ |
| 1563 | /* Write the end of the PNG file. */␍␊ |
| 1564 | PNG_EXPORT(61, void, png_write_end,␍␊ |
| 1565 | (png_structp png_ptr, png_infop info_ptr));␍␊ |
| 1566 | ␍␊ |
| 1567 | #ifdef PNG_SEQUENTIAL_READ_SUPPORTED␍␊ |
| 1568 | /* Read the end of the PNG file. */␍␊ |
| 1569 | PNG_EXPORT(62, void, png_read_end, (png_structp png_ptr, png_infop info_ptr));␍␊ |
| 1570 | #endif␍␊ |
| 1571 | ␍␊ |
| 1572 | /* Free any memory associated with the png_info_struct */␍␊ |
| 1573 | PNG_EXPORT(63, void, png_destroy_info_struct, (png_structp png_ptr,␍␊ |
| 1574 | png_infopp info_ptr_ptr));␍␊ |
| 1575 | ␍␊ |
| 1576 | /* Free any memory associated with the png_struct and the png_info_structs */␍␊ |
| 1577 | PNG_EXPORT(64, void, png_destroy_read_struct, (png_structpp png_ptr_ptr,␍␊ |
| 1578 | png_infopp info_ptr_ptr, png_infopp end_info_ptr_ptr));␍␊ |
| 1579 | ␍␊ |
| 1580 | /* Free any memory associated with the png_struct and the png_info_structs */␍␊ |
| 1581 | PNG_EXPORT(65, void, png_destroy_write_struct, (png_structpp png_ptr_ptr,␍␊ |
| 1582 | png_infopp info_ptr_ptr));␍␊ |
| 1583 | ␍␊ |
| 1584 | /* Set the libpng method of handling chunk CRC errors */␍␊ |
| 1585 | PNG_EXPORT(66, void, png_set_crc_action,␍␊ |
| 1586 | (png_structp png_ptr, int crit_action, int ancil_action));␍␊ |
| 1587 | ␍␊ |
| 1588 | /* Values for png_set_crc_action() say how to handle CRC errors in␍␊ |
| 1589 | * ancillary and critical chunks, and whether to use the data contained␍␊ |
| 1590 | * therein. Note that it is impossible to "discard" data in a critical␍␊ |
| 1591 | * chunk. For versions prior to 0.90, the action was always error/quit,␍␊ |
| 1592 | * whereas in version 0.90 and later, the action for CRC errors in ancillary␍␊ |
| 1593 | * chunks is warn/discard. These values should NOT be changed.␍␊ |
| 1594 | *␍␊ |
| 1595 | * value action:critical action:ancillary␍␊ |
| 1596 | */␍␊ |
| 1597 | #define PNG_CRC_DEFAULT 0 /* error/quit warn/discard data */␍␊ |
| 1598 | #define PNG_CRC_ERROR_QUIT 1 /* error/quit error/quit */␍␊ |
| 1599 | #define PNG_CRC_WARN_DISCARD 2 /* (INVALID) warn/discard data */␍␊ |
| 1600 | #define PNG_CRC_WARN_USE 3 /* warn/use data warn/use data */␍␊ |
| 1601 | #define PNG_CRC_QUIET_USE 4 /* quiet/use data quiet/use data */␍␊ |
| 1602 | #define PNG_CRC_NO_CHANGE 5 /* use current value use current value */␍␊ |
| 1603 | ␍␊ |
| 1604 | /* These functions give the user control over the scan-line filtering in␍␊ |
| 1605 | * libpng and the compression methods used by zlib. These functions are␍␊ |
| 1606 | * mainly useful for testing, as the defaults should work with most users.␍␊ |
| 1607 | * Those users who are tight on memory or want faster performance at the␍␊ |
| 1608 | * expense of compression can modify them. See the compression library␍␊ |
| 1609 | * header file (zlib.h) for an explination of the compression functions.␍␊ |
| 1610 | */␍␊ |
| 1611 | ␍␊ |
| 1612 | /* Set the filtering method(s) used by libpng. Currently, the only valid␍␊ |
| 1613 | * value for "method" is 0.␍␊ |
| 1614 | */␍␊ |
| 1615 | PNG_EXPORT(67, void, png_set_filter,␍␊ |
| 1616 | (png_structp png_ptr, int method, int filters));␍␊ |
| 1617 | ␍␊ |
| 1618 | /* Flags for png_set_filter() to say which filters to use. The flags␍␊ |
| 1619 | * are chosen so that they don't conflict with real filter types␍␊ |
| 1620 | * below, in case they are supplied instead of the #defined constants.␍␊ |
| 1621 | * These values should NOT be changed.␍␊ |
| 1622 | */␍␊ |
| 1623 | #define PNG_NO_FILTERS 0x00␍␊ |
| 1624 | #define PNG_FILTER_NONE 0x08␍␊ |
| 1625 | #define PNG_FILTER_SUB 0x10␍␊ |
| 1626 | #define PNG_FILTER_UP 0x20␍␊ |
| 1627 | #define PNG_FILTER_AVG 0x40␍␊ |
| 1628 | #define PNG_FILTER_PAETH 0x80␍␊ |
| 1629 | #define PNG_ALL_FILTERS (PNG_FILTER_NONE | PNG_FILTER_SUB | PNG_FILTER_UP | \␍␊ |
| 1630 | PNG_FILTER_AVG | PNG_FILTER_PAETH)␍␊ |
| 1631 | ␍␊ |
| 1632 | /* Filter values (not flags) - used in pngwrite.c, pngwutil.c for now.␍␊ |
| 1633 | * These defines should NOT be changed.␍␊ |
| 1634 | */␍␊ |
| 1635 | #define PNG_FILTER_VALUE_NONE 0␍␊ |
| 1636 | #define PNG_FILTER_VALUE_SUB 1␍␊ |
| 1637 | #define PNG_FILTER_VALUE_UP 2␍␊ |
| 1638 | #define PNG_FILTER_VALUE_AVG 3␍␊ |
| 1639 | #define PNG_FILTER_VALUE_PAETH 4␍␊ |
| 1640 | #define PNG_FILTER_VALUE_LAST 5␍␊ |
| 1641 | ␍␊ |
| 1642 | #ifdef PNG_WRITE_WEIGHTED_FILTER_SUPPORTED /* EXPERIMENTAL */␍␊ |
| 1643 | /* The "heuristic_method" is given by one of the PNG_FILTER_HEURISTIC_␍␊ |
| 1644 | * defines, either the default (minimum-sum-of-absolute-differences), or␍␊ |
| 1645 | * the experimental method (weighted-minimum-sum-of-absolute-differences).␍␊ |
| 1646 | *␍␊ |
| 1647 | * Weights are factors >= 1.0, indicating how important it is to keep the␍␊ |
| 1648 | * filter type consistent between rows. Larger numbers mean the current␍␊ |
| 1649 | * filter is that many times as likely to be the same as the "num_weights"␍␊ |
| 1650 | * previous filters. This is cumulative for each previous row with a weight.␍␊ |
| 1651 | * There needs to be "num_weights" values in "filter_weights", or it can be␍␊ |
| 1652 | * NULL if the weights aren't being specified. Weights have no influence on␍␊ |
| 1653 | * the selection of the first row filter. Well chosen weights can (in theory)␍␊ |
| 1654 | * improve the compression for a given image.␍␊ |
| 1655 | *␍␊ |
| 1656 | * Costs are factors >= 1.0 indicating the relative decoding costs of a␍␊ |
| 1657 | * filter type. Higher costs indicate more decoding expense, and are␍␊ |
| 1658 | * therefore less likely to be selected over a filter with lower computational␍␊ |
| 1659 | * costs. There needs to be a value in "filter_costs" for each valid filter␍␊ |
| 1660 | * type (given by PNG_FILTER_VALUE_LAST), or it can be NULL if you aren't␍␊ |
| 1661 | * setting the costs. Costs try to improve the speed of decompression without␍␊ |
| 1662 | * unduly increasing the compressed image size.␍␊ |
| 1663 | *␍␊ |
| 1664 | * A negative weight or cost indicates the default value is to be used, and␍␊ |
| 1665 | * values in the range [0.0, 1.0) indicate the value is to remain unchanged.␍␊ |
| 1666 | * The default values for both weights and costs are currently 1.0, but may␍␊ |
| 1667 | * change if good general weighting/cost heuristics can be found. If both␍␊ |
| 1668 | * the weights and costs are set to 1.0, this degenerates the WEIGHTED method␍␊ |
| 1669 | * to the UNWEIGHTED method, but with added encoding time/computation.␍␊ |
| 1670 | */␍␊ |
| 1671 | PNG_FP_EXPORT(68, void, png_set_filter_heuristics, (png_structp png_ptr,␍␊ |
| 1672 | int heuristic_method, int num_weights, png_const_doublep filter_weights,␍␊ |
| 1673 | png_const_doublep filter_costs))␍␊ |
| 1674 | PNG_FIXED_EXPORT(209, void, png_set_filter_heuristics_fixed,␍␊ |
| 1675 | (png_structp png_ptr,␍␊ |
| 1676 | int heuristic_method, int num_weights, png_const_fixed_point_p␍␊ |
| 1677 | filter_weights, png_const_fixed_point_p filter_costs))␍␊ |
| 1678 | #endif /* PNG_WRITE_WEIGHTED_FILTER_SUPPORTED */␍␊ |
| 1679 | ␍␊ |
| 1680 | /* Heuristic used for row filter selection. These defines should NOT be␍␊ |
| 1681 | * changed.␍␊ |
| 1682 | */␍␊ |
| 1683 | #define PNG_FILTER_HEURISTIC_DEFAULT 0 /* Currently "UNWEIGHTED" */␍␊ |
| 1684 | #define PNG_FILTER_HEURISTIC_UNWEIGHTED 1 /* Used by libpng < 0.95 */␍␊ |
| 1685 | #define PNG_FILTER_HEURISTIC_WEIGHTED 2 /* Experimental feature */␍␊ |
| 1686 | #define PNG_FILTER_HEURISTIC_LAST 3 /* Not a valid value */␍␊ |
| 1687 | ␍␊ |
| 1688 | #ifdef PNG_WRITE_SUPPORTED␍␊ |
| 1689 | /* Set the library compression level. Currently, valid values range from␍␊ |
| 1690 | * 0 - 9, corresponding directly to the zlib compression levels 0 - 9␍␊ |
| 1691 | * (0 - no compression, 9 - "maximal" compression). Note that tests have␍␊ |
| 1692 | * shown that zlib compression levels 3-6 usually perform as well as level 9␍␊ |
| 1693 | * for PNG images, and do considerably fewer caclulations. In the future,␍␊ |
| 1694 | * these values may not correspond directly to the zlib compression levels.␍␊ |
| 1695 | */␍␊ |
| 1696 | PNG_EXPORT(69, void, png_set_compression_level,␍␊ |
| 1697 | (png_structp png_ptr, int level));␍␊ |
| 1698 | ␍␊ |
| 1699 | PNG_EXPORT(70, void, png_set_compression_mem_level, (png_structp png_ptr,␍␊ |
| 1700 | int mem_level));␍␊ |
| 1701 | ␍␊ |
| 1702 | PNG_EXPORT(71, void, png_set_compression_strategy, (png_structp png_ptr,␍␊ |
| 1703 | int strategy));␍␊ |
| 1704 | ␍␊ |
| 1705 | /* If PNG_WRITE_OPTIMIZE_CMF_SUPPORTED is defined, libpng will use a␍␊ |
| 1706 | * smaller value of window_bits if it can do so safely.␍␊ |
| 1707 | */␍␊ |
| 1708 | PNG_EXPORT(72, void, png_set_compression_window_bits, (png_structp png_ptr,␍␊ |
| 1709 | int window_bits));␍␊ |
| 1710 | ␍␊ |
| 1711 | PNG_EXPORT(73, void, png_set_compression_method, (png_structp png_ptr,␍␊ |
| 1712 | int method));␍␊ |
| 1713 | #endif␍␊ |
| 1714 | ␍␊ |
| 1715 | #ifdef PNG_WRITE_CUSTOMIZE_ZTXT_COMPRESSION_SUPPORTED␍␊ |
| 1716 | /* Also set zlib parameters for compressing non-IDAT chunks */␍␊ |
| 1717 | PNG_EXPORT(222, void, png_set_text_compression_level,␍␊ |
| 1718 | (png_structp png_ptr, int level));␍␊ |
| 1719 | ␍␊ |
| 1720 | PNG_EXPORT(223, void, png_set_text_compression_mem_level, (png_structp png_ptr,␍␊ |
| 1721 | int mem_level));␍␊ |
| 1722 | ␍␊ |
| 1723 | PNG_EXPORT(224, void, png_set_text_compression_strategy, (png_structp png_ptr,␍␊ |
| 1724 | int strategy));␍␊ |
| 1725 | ␍␊ |
| 1726 | /* If PNG_WRITE_OPTIMIZE_CMF_SUPPORTED is defined, libpng will use a␍␊ |
| 1727 | * smaller value of window_bits if it can do so safely.␍␊ |
| 1728 | */␍␊ |
| 1729 | PNG_EXPORT(225, void, png_set_text_compression_window_bits, (png_structp␍␊ |
| 1730 | png_ptr, int window_bits));␍␊ |
| 1731 | ␍␊ |
| 1732 | PNG_EXPORT(226, void, png_set_text_compression_method, (png_structp png_ptr,␍␊ |
| 1733 | int method));␍␊ |
| 1734 | #endif /* PNG_WRITE_CUSTOMIZE_ZTXT_COMPRESSION_SUPPORTED */␍␊ |
| 1735 | ␍␊ |
| 1736 | /* These next functions are called for input/output, memory, and error␍␊ |
| 1737 | * handling. They are in the file pngrio.c, pngwio.c, and pngerror.c,␍␊ |
| 1738 | * and call standard C I/O routines such as fread(), fwrite(), and␍␊ |
| 1739 | * fprintf(). These functions can be made to use other I/O routines␍␊ |
| 1740 | * at run time for those applications that need to handle I/O in a␍␊ |
| 1741 | * different manner by calling png_set_???_fn(). See libpng-manual.txt for␍␊ |
| 1742 | * more information.␍␊ |
| 1743 | */␍␊ |
| 1744 | ␍␊ |
| 1745 | #ifdef PNG_STDIO_SUPPORTED␍␊ |
| 1746 | /* Initialize the input/output for the PNG file to the default functions. */␍␊ |
| 1747 | PNG_EXPORT(74, void, png_init_io, (png_structp png_ptr, png_FILE_p fp));␍␊ |
| 1748 | #endif␍␊ |
| 1749 | ␍␊ |
| 1750 | /* Replace the (error and abort), and warning functions with user␍␊ |
| 1751 | * supplied functions. If no messages are to be printed you must still␍␊ |
| 1752 | * write and use replacement functions. The replacement error_fn should␍␊ |
| 1753 | * still do a longjmp to the last setjmp location if you are using this␍␊ |
| 1754 | * method of error handling. If error_fn or warning_fn is NULL, the␍␊ |
| 1755 | * default function will be used.␍␊ |
| 1756 | */␍␊ |
| 1757 | ␍␊ |
| 1758 | PNG_EXPORT(75, void, png_set_error_fn,␍␊ |
| 1759 | (png_structp png_ptr, png_voidp error_ptr,␍␊ |
| 1760 | png_error_ptr error_fn, png_error_ptr warning_fn));␍␊ |
| 1761 | ␍␊ |
| 1762 | /* Return the user pointer associated with the error functions */␍␊ |
| 1763 | PNG_EXPORT(76, png_voidp, png_get_error_ptr, (png_const_structp png_ptr));␍␊ |
| 1764 | ␍␊ |
| 1765 | /* Replace the default data output functions with a user supplied one(s).␍␊ |
| 1766 | * If buffered output is not used, then output_flush_fn can be set to NULL.␍␊ |
| 1767 | * If PNG_WRITE_FLUSH_SUPPORTED is not defined at libpng compile time␍␊ |
| 1768 | * output_flush_fn will be ignored (and thus can be NULL).␍␊ |
| 1769 | * It is probably a mistake to use NULL for output_flush_fn if␍␊ |
| 1770 | * write_data_fn is not also NULL unless you have built libpng with␍␊ |
| 1771 | * PNG_WRITE_FLUSH_SUPPORTED undefined, because in this case libpng's␍␊ |
| 1772 | * default flush function, which uses the standard *FILE structure, will␍␊ |
| 1773 | * be used.␍␊ |
| 1774 | */␍␊ |
| 1775 | PNG_EXPORT(77, void, png_set_write_fn, (png_structp png_ptr, png_voidp io_ptr,␍␊ |
| 1776 | png_rw_ptr write_data_fn, png_flush_ptr output_flush_fn));␍␊ |
| 1777 | ␍␊ |
| 1778 | /* Replace the default data input function with a user supplied one. */␍␊ |
| 1779 | PNG_EXPORT(78, void, png_set_read_fn, (png_structp png_ptr, png_voidp io_ptr,␍␊ |
| 1780 | png_rw_ptr read_data_fn));␍␊ |
| 1781 | ␍␊ |
| 1782 | /* Return the user pointer associated with the I/O functions */␍␊ |
| 1783 | PNG_EXPORT(79, png_voidp, png_get_io_ptr, (png_structp png_ptr));␍␊ |
| 1784 | ␍␊ |
| 1785 | PNG_EXPORT(80, void, png_set_read_status_fn, (png_structp png_ptr,␍␊ |
| 1786 | png_read_status_ptr read_row_fn));␍␊ |
| 1787 | ␍␊ |
| 1788 | PNG_EXPORT(81, void, png_set_write_status_fn, (png_structp png_ptr,␍␊ |
| 1789 | png_write_status_ptr write_row_fn));␍␊ |
| 1790 | ␍␊ |
| 1791 | #ifdef PNG_USER_MEM_SUPPORTED␍␊ |
| 1792 | /* Replace the default memory allocation functions with user supplied one(s). */␍␊ |
| 1793 | PNG_EXPORT(82, void, png_set_mem_fn, (png_structp png_ptr, png_voidp mem_ptr,␍␊ |
| 1794 | png_malloc_ptr malloc_fn, png_free_ptr free_fn));␍␊ |
| 1795 | /* Return the user pointer associated with the memory functions */␍␊ |
| 1796 | PNG_EXPORT(83, png_voidp, png_get_mem_ptr, (png_const_structp png_ptr));␍␊ |
| 1797 | #endif␍␊ |
| 1798 | ␍␊ |
| 1799 | #ifdef PNG_READ_USER_TRANSFORM_SUPPORTED␍␊ |
| 1800 | PNG_EXPORT(84, void, png_set_read_user_transform_fn, (png_structp png_ptr,␍␊ |
| 1801 | png_user_transform_ptr read_user_transform_fn));␍␊ |
| 1802 | #endif␍␊ |
| 1803 | ␍␊ |
| 1804 | #ifdef PNG_WRITE_USER_TRANSFORM_SUPPORTED␍␊ |
| 1805 | PNG_EXPORT(85, void, png_set_write_user_transform_fn, (png_structp png_ptr,␍␊ |
| 1806 | png_user_transform_ptr write_user_transform_fn));␍␊ |
| 1807 | #endif␍␊ |
| 1808 | ␍␊ |
| 1809 | #ifdef PNG_USER_TRANSFORM_PTR_SUPPORTED␍␊ |
| 1810 | PNG_EXPORT(86, void, png_set_user_transform_info, (png_structp png_ptr,␍␊ |
| 1811 | png_voidp user_transform_ptr, int user_transform_depth,␍␊ |
| 1812 | int user_transform_channels));␍␊ |
| 1813 | /* Return the user pointer associated with the user transform functions */␍␊ |
| 1814 | PNG_EXPORT(87, png_voidp, png_get_user_transform_ptr,␍␊ |
| 1815 | (png_const_structp png_ptr));␍␊ |
| 1816 | #endif␍␊ |
| 1817 | ␍␊ |
| 1818 | #ifdef PNG_USER_TRANSFORM_INFO_SUPPORTED␍␊ |
| 1819 | /* Return information about the row currently being processed. Note that these␍␊ |
| 1820 | * APIs do not fail but will return unexpected results if called outside a user␍␊ |
| 1821 | * transform callback. Also note that when transforming an interlaced image the␍␊ |
| 1822 | * row number is the row number within the sub-image of the interlace pass, so␍␊ |
| 1823 | * the value will increase to the height of the sub-image (not the full image)␍␊ |
| 1824 | * then reset to 0 for the next pass.␍␊ |
| 1825 | *␍␊ |
| 1826 | * Use PNG_ROW_FROM_PASS_ROW(row, pass) and PNG_COL_FROM_PASS_COL(col, pass) to␍␊ |
| 1827 | * find the output pixel (x,y) given an interlaced sub-image pixel␍␊ |
| 1828 | * (row,col,pass). (See below for these macros.)␍␊ |
| 1829 | */␍␊ |
| 1830 | PNG_EXPORT(217, png_uint_32, png_get_current_row_number, (png_const_structp));␍␊ |
| 1831 | PNG_EXPORT(218, png_byte, png_get_current_pass_number, (png_const_structp));␍␊ |
| 1832 | #endif␍␊ |
| 1833 | ␍␊ |
| 1834 | #ifdef PNG_USER_CHUNKS_SUPPORTED␍␊ |
| 1835 | PNG_EXPORT(88, void, png_set_read_user_chunk_fn, (png_structp png_ptr,␍␊ |
| 1836 | png_voidp user_chunk_ptr, png_user_chunk_ptr read_user_chunk_fn));␍␊ |
| 1837 | PNG_EXPORT(89, png_voidp, png_get_user_chunk_ptr, (png_const_structp png_ptr));␍␊ |
| 1838 | #endif␍␊ |
| 1839 | ␍␊ |
| 1840 | #ifdef PNG_PROGRESSIVE_READ_SUPPORTED␍␊ |
| 1841 | /* Sets the function callbacks for the push reader, and a pointer to a␍␊ |
| 1842 | * user-defined structure available to the callback functions.␍␊ |
| 1843 | */␍␊ |
| 1844 | PNG_EXPORT(90, void, png_set_progressive_read_fn, (png_structp png_ptr,␍␊ |
| 1845 | png_voidp progressive_ptr, png_progressive_info_ptr info_fn,␍␊ |
| 1846 | png_progressive_row_ptr row_fn, png_progressive_end_ptr end_fn));␍␊ |
| 1847 | ␍␊ |
| 1848 | /* Returns the user pointer associated with the push read functions */␍␊ |
| 1849 | PNG_EXPORT(91, png_voidp, png_get_progressive_ptr, (png_const_structp png_ptr));␍␊ |
| 1850 | ␍␊ |
| 1851 | /* Function to be called when data becomes available */␍␊ |
| 1852 | PNG_EXPORT(92, void, png_process_data,␍␊ |
| 1853 | (png_structp png_ptr, png_infop info_ptr,␍␊ |
| 1854 | png_bytep buffer, png_size_t buffer_size));␍␊ |
| 1855 | ␍␊ |
| 1856 | /* A function which may be called *only* within png_process_data to stop the␍␊ |
| 1857 | * processing of any more data. The function returns the number of bytes␍␊ |
| 1858 | * remaining, excluding any that libpng has cached internally. A subsequent␍␊ |
| 1859 | * call to png_process_data must supply these bytes again. If the argument␍␊ |
| 1860 | * 'save' is set to true the routine will first save all the pending data and␍␊ |
| 1861 | * will always return 0.␍␊ |
| 1862 | */␍␊ |
| 1863 | PNG_EXPORT(219, png_size_t, png_process_data_pause, (png_structp, int save));␍␊ |
| 1864 | ␍␊ |
| 1865 | /* A function which may be called *only* outside (after) a call to␍␊ |
| 1866 | * png_process_data. It returns the number of bytes of data to skip in the␍␊ |
| 1867 | * input. Normally it will return 0, but if it returns a non-zero value the␍␊ |
| 1868 | * application must skip than number of bytes of input data and pass the␍␊ |
| 1869 | * following data to the next call to png_process_data.␍␊ |
| 1870 | */␍␊ |
| 1871 | PNG_EXPORT(220, png_uint_32, png_process_data_skip, (png_structp));␍␊ |
| 1872 | ␍␊ |
| 1873 | #ifdef PNG_READ_INTERLACING_SUPPORTED␍␊ |
| 1874 | /* Function that combines rows. 'new_row' is a flag that should come from␍␊ |
| 1875 | * the callback and be non-NULL if anything needs to be done; the library␍␊ |
| 1876 | * stores its own version of the new data internally and ignores the passed␍␊ |
| 1877 | * in value.␍␊ |
| 1878 | */␍␊ |
| 1879 | PNG_EXPORT(93, void, png_progressive_combine_row, (png_structp png_ptr,␍␊ |
| 1880 | png_bytep old_row, png_const_bytep new_row));␍␊ |
| 1881 | #endif /* PNG_READ_INTERLACING_SUPPORTED */␍␊ |
| 1882 | #endif /* PNG_PROGRESSIVE_READ_SUPPORTED */␍␊ |
| 1883 | ␍␊ |
| 1884 | PNG_EXPORTA(94, png_voidp, png_malloc,␍␊ |
| 1885 | (png_structp png_ptr, png_alloc_size_t size),␍␊ |
| 1886 | PNG_ALLOCATED);␍␊ |
| 1887 | /* Added at libpng version 1.4.0 */␍␊ |
| 1888 | PNG_EXPORTA(95, png_voidp, png_calloc,␍␊ |
| 1889 | (png_structp png_ptr, png_alloc_size_t size),␍␊ |
| 1890 | PNG_ALLOCATED);␍␊ |
| 1891 | ␍␊ |
| 1892 | /* Added at libpng version 1.2.4 */␍␊ |
| 1893 | PNG_EXPORTA(96, png_voidp, png_malloc_warn, (png_structp png_ptr,␍␊ |
| 1894 | png_alloc_size_t size), PNG_ALLOCATED);␍␊ |
| 1895 | ␍␊ |
| 1896 | /* Frees a pointer allocated by png_malloc() */␍␊ |
| 1897 | PNG_EXPORT(97, void, png_free, (png_structp png_ptr, png_voidp ptr));␍␊ |
| 1898 | ␍␊ |
| 1899 | /* Free data that was allocated internally */␍␊ |
| 1900 | PNG_EXPORT(98, void, png_free_data,␍␊ |
| 1901 | (png_structp png_ptr, png_infop info_ptr, png_uint_32 free_me, int num));␍␊ |
| 1902 | ␍␊ |
| 1903 | /* Reassign responsibility for freeing existing data, whether allocated␍␊ |
| 1904 | * by libpng or by the application */␍␊ |
| 1905 | PNG_EXPORT(99, void, png_data_freer,␍␊ |
| 1906 | (png_structp png_ptr, png_infop info_ptr, int freer, png_uint_32 mask));␍␊ |
| 1907 | ␍␊ |
| 1908 | /* Assignments for png_data_freer */␍␊ |
| 1909 | #define PNG_DESTROY_WILL_FREE_DATA 1␍␊ |
| 1910 | #define PNG_SET_WILL_FREE_DATA 1␍␊ |
| 1911 | #define PNG_USER_WILL_FREE_DATA 2␍␊ |
| 1912 | /* Flags for png_ptr->free_me and info_ptr->free_me */␍␊ |
| 1913 | #define PNG_FREE_HIST 0x0008␍␊ |
| 1914 | #define PNG_FREE_ICCP 0x0010␍␊ |
| 1915 | #define PNG_FREE_SPLT 0x0020␍␊ |
| 1916 | #define PNG_FREE_ROWS 0x0040␍␊ |
| 1917 | #define PNG_FREE_PCAL 0x0080␍␊ |
| 1918 | #define PNG_FREE_SCAL 0x0100␍␊ |
| 1919 | #define PNG_FREE_UNKN 0x0200␍␊ |
| 1920 | #define PNG_FREE_LIST 0x0400␍␊ |
| 1921 | #define PNG_FREE_PLTE 0x1000␍␊ |
| 1922 | #define PNG_FREE_TRNS 0x2000␍␊ |
| 1923 | #define PNG_FREE_TEXT 0x4000␍␊ |
| 1924 | #define PNG_FREE_ALL 0x7fff␍␊ |
| 1925 | #define PNG_FREE_MUL 0x4220 /* PNG_FREE_SPLT|PNG_FREE_TEXT|PNG_FREE_UNKN */␍␊ |
| 1926 | ␍␊ |
| 1927 | #ifdef PNG_USER_MEM_SUPPORTED␍␊ |
| 1928 | PNG_EXPORTA(100, png_voidp, png_malloc_default, (png_structp png_ptr,␍␊ |
| 1929 | png_alloc_size_t size), PNG_ALLOCATED);␍␊ |
| 1930 | PNG_EXPORT(101, void, png_free_default, (png_structp png_ptr, png_voidp ptr));␍␊ |
| 1931 | #endif␍␊ |
| 1932 | ␍␊ |
| 1933 | #ifdef PNG_ERROR_TEXT_SUPPORTED␍␊ |
| 1934 | /* Fatal error in PNG image of libpng - can't continue */␍␊ |
| 1935 | PNG_EXPORTA(102, void, png_error,␍␊ |
| 1936 | (png_structp png_ptr, png_const_charp error_message),␍␊ |
| 1937 | PNG_NORETURN);␍␊ |
| 1938 | ␍␊ |
| 1939 | /* The same, but the chunk name is prepended to the error string. */␍␊ |
| 1940 | PNG_EXPORTA(103, void, png_chunk_error, (png_structp png_ptr,␍␊ |
| 1941 | png_const_charp error_message), PNG_NORETURN);␍␊ |
| 1942 | ␍␊ |
| 1943 | #else␍␊ |
| 1944 | /* Fatal error in PNG image of libpng - can't continue */␍␊ |
| 1945 | PNG_EXPORTA(104, void, png_err, (png_structp png_ptr), PNG_NORETURN);␍␊ |
| 1946 | #endif␍␊ |
| 1947 | ␍␊ |
| 1948 | #ifdef PNG_WARNINGS_SUPPORTED␍␊ |
| 1949 | /* Non-fatal error in libpng. Can continue, but may have a problem. */␍␊ |
| 1950 | PNG_EXPORT(105, void, png_warning, (png_structp png_ptr,␍␊ |
| 1951 | png_const_charp warning_message));␍␊ |
| 1952 | ␍␊ |
| 1953 | /* Non-fatal error in libpng, chunk name is prepended to message. */␍␊ |
| 1954 | PNG_EXPORT(106, void, png_chunk_warning, (png_structp png_ptr,␍␊ |
| 1955 | png_const_charp warning_message));␍␊ |
| 1956 | #endif␍␊ |
| 1957 | ␍␊ |
| 1958 | #ifdef PNG_BENIGN_ERRORS_SUPPORTED␍␊ |
| 1959 | /* Benign error in libpng. Can continue, but may have a problem.␍␊ |
| 1960 | * User can choose whether to handle as a fatal error or as a warning. */␍␊ |
| 1961 | # undef png_benign_error␍␊ |
| 1962 | PNG_EXPORT(107, void, png_benign_error, (png_structp png_ptr,␍␊ |
| 1963 | png_const_charp warning_message));␍␊ |
| 1964 | ␍␊ |
| 1965 | /* Same, chunk name is prepended to message. */␍␊ |
| 1966 | # undef png_chunk_benign_error␍␊ |
| 1967 | PNG_EXPORT(108, void, png_chunk_benign_error, (png_structp png_ptr,␍␊ |
| 1968 | png_const_charp warning_message));␍␊ |
| 1969 | ␍␊ |
| 1970 | PNG_EXPORT(109, void, png_set_benign_errors,␍␊ |
| 1971 | (png_structp png_ptr, int allowed));␍␊ |
| 1972 | #else␍␊ |
| 1973 | # ifdef PNG_ALLOW_BENIGN_ERRORS␍␊ |
| 1974 | # define png_benign_error png_warning␍␊ |
| 1975 | # define png_chunk_benign_error png_chunk_warning␍␊ |
| 1976 | # else␍␊ |
| 1977 | # define png_benign_error png_error␍␊ |
| 1978 | # define png_chunk_benign_error png_chunk_error␍␊ |
| 1979 | # endif␍␊ |
| 1980 | #endif␍␊ |
| 1981 | ␍␊ |
| 1982 | /* The png_set_<chunk> functions are for storing values in the png_info_struct.␍␊ |
| 1983 | * Similarly, the png_get_<chunk> calls are used to read values from the␍␊ |
| 1984 | * png_info_struct, either storing the parameters in the passed variables, or␍␊ |
| 1985 | * setting pointers into the png_info_struct where the data is stored. The␍␊ |
| 1986 | * png_get_<chunk> functions return a non-zero value if the data was available␍␊ |
| 1987 | * in info_ptr, or return zero and do not change any of the parameters if the␍␊ |
| 1988 | * data was not available.␍␊ |
| 1989 | *␍␊ |
| 1990 | * These functions should be used instead of directly accessing png_info␍␊ |
| 1991 | * to avoid problems with future changes in the size and internal layout of␍␊ |
| 1992 | * png_info_struct.␍␊ |
| 1993 | */␍␊ |
| 1994 | /* Returns "flag" if chunk data is valid in info_ptr. */␍␊ |
| 1995 | PNG_EXPORT(110, png_uint_32, png_get_valid,␍␊ |
| 1996 | (png_const_structp png_ptr, png_const_infop info_ptr,␍␊ |
| 1997 | png_uint_32 flag));␍␊ |
| 1998 | ␍␊ |
| 1999 | /* Returns number of bytes needed to hold a transformed row. */␍␊ |
| 2000 | PNG_EXPORT(111, png_size_t, png_get_rowbytes, (png_const_structp png_ptr,␍␊ |
| 2001 | png_const_infop info_ptr));␍␊ |
| 2002 | ␍␊ |
| 2003 | #ifdef PNG_INFO_IMAGE_SUPPORTED␍␊ |
| 2004 | /* Returns row_pointers, which is an array of pointers to scanlines that was␍␊ |
| 2005 | * returned from png_read_png().␍␊ |
| 2006 | */␍␊ |
| 2007 | PNG_EXPORT(112, png_bytepp, png_get_rows,␍␊ |
| 2008 | (png_const_structp png_ptr, png_const_infop info_ptr));␍␊ |
| 2009 | /* Set row_pointers, which is an array of pointers to scanlines for use␍␊ |
| 2010 | * by png_write_png().␍␊ |
| 2011 | */␍␊ |
| 2012 | PNG_EXPORT(113, void, png_set_rows, (png_structp png_ptr,␍␊ |
| 2013 | png_infop info_ptr, png_bytepp row_pointers));␍␊ |
| 2014 | #endif␍␊ |
| 2015 | ␍␊ |
| 2016 | /* Returns number of color channels in image. */␍␊ |
| 2017 | PNG_EXPORT(114, png_byte, png_get_channels,␍␊ |
| 2018 | (png_const_structp png_ptr, png_const_infop info_ptr));␍␊ |
| 2019 | ␍␊ |
| 2020 | #ifdef PNG_EASY_ACCESS_SUPPORTED␍␊ |
| 2021 | /* Returns image width in pixels. */␍␊ |
| 2022 | PNG_EXPORT(115, png_uint_32, png_get_image_width, (png_const_structp png_ptr,␍␊ |
| 2023 | png_const_infop info_ptr));␍␊ |
| 2024 | ␍␊ |
| 2025 | /* Returns image height in pixels. */␍␊ |
| 2026 | PNG_EXPORT(116, png_uint_32, png_get_image_height, (png_const_structp png_ptr,␍␊ |
| 2027 | png_const_infop info_ptr));␍␊ |
| 2028 | ␍␊ |
| 2029 | /* Returns image bit_depth. */␍␊ |
| 2030 | PNG_EXPORT(117, png_byte, png_get_bit_depth,␍␊ |
| 2031 | (png_const_structp png_ptr, png_const_infop info_ptr));␍␊ |
| 2032 | ␍␊ |
| 2033 | /* Returns image color_type. */␍␊ |
| 2034 | PNG_EXPORT(118, png_byte, png_get_color_type, (png_const_structp png_ptr,␍␊ |
| 2035 | png_const_infop info_ptr));␍␊ |
| 2036 | ␍␊ |
| 2037 | /* Returns image filter_type. */␍␊ |
| 2038 | PNG_EXPORT(119, png_byte, png_get_filter_type, (png_const_structp png_ptr,␍␊ |
| 2039 | png_const_infop info_ptr));␍␊ |
| 2040 | ␍␊ |
| 2041 | /* Returns image interlace_type. */␍␊ |
| 2042 | PNG_EXPORT(120, png_byte, png_get_interlace_type, (png_const_structp png_ptr,␍␊ |
| 2043 | png_const_infop info_ptr));␍␊ |
| 2044 | ␍␊ |
| 2045 | /* Returns image compression_type. */␍␊ |
| 2046 | PNG_EXPORT(121, png_byte, png_get_compression_type, (png_const_structp png_ptr,␍␊ |
| 2047 | png_const_infop info_ptr));␍␊ |
| 2048 | ␍␊ |
| 2049 | /* Returns image resolution in pixels per meter, from pHYs chunk data. */␍␊ |
| 2050 | PNG_EXPORT(122, png_uint_32, png_get_pixels_per_meter,␍␊ |
| 2051 | (png_const_structp png_ptr, png_const_infop info_ptr));␍␊ |
| 2052 | PNG_EXPORT(123, png_uint_32, png_get_x_pixels_per_meter,␍␊ |
| 2053 | (png_const_structp png_ptr, png_const_infop info_ptr));␍␊ |
| 2054 | PNG_EXPORT(124, png_uint_32, png_get_y_pixels_per_meter,␍␊ |
| 2055 | (png_const_structp png_ptr, png_const_infop info_ptr));␍␊ |
| 2056 | ␍␊ |
| 2057 | /* Returns pixel aspect ratio, computed from pHYs chunk data. */␍␊ |
| 2058 | PNG_FP_EXPORT(125, float, png_get_pixel_aspect_ratio,␍␊ |
| 2059 | (png_const_structp png_ptr, png_const_infop info_ptr))␍␊ |
| 2060 | PNG_FIXED_EXPORT(210, png_fixed_point, png_get_pixel_aspect_ratio_fixed,␍␊ |
| 2061 | (png_const_structp png_ptr, png_const_infop info_ptr))␍␊ |
| 2062 | ␍␊ |
| 2063 | /* Returns image x, y offset in pixels or microns, from oFFs chunk data. */␍␊ |
| 2064 | PNG_EXPORT(126, png_int_32, png_get_x_offset_pixels,␍␊ |
| 2065 | (png_const_structp png_ptr, png_const_infop info_ptr));␍␊ |
| 2066 | PNG_EXPORT(127, png_int_32, png_get_y_offset_pixels,␍␊ |
| 2067 | (png_const_structp png_ptr, png_const_infop info_ptr));␍␊ |
| 2068 | PNG_EXPORT(128, png_int_32, png_get_x_offset_microns,␍␊ |
| 2069 | (png_const_structp png_ptr, png_const_infop info_ptr));␍␊ |
| 2070 | PNG_EXPORT(129, png_int_32, png_get_y_offset_microns,␍␊ |
| 2071 | (png_const_structp png_ptr, png_const_infop info_ptr));␍␊ |
| 2072 | ␍␊ |
| 2073 | #endif /* PNG_EASY_ACCESS_SUPPORTED */␍␊ |
| 2074 | ␍␊ |
| 2075 | /* Returns pointer to signature string read from PNG header */␍␊ |
| 2076 | PNG_EXPORT(130, png_const_bytep, png_get_signature,␍␊ |
| 2077 | (png_const_structp png_ptr, png_infop info_ptr));␍␊ |
| 2078 | ␍␊ |
| 2079 | #ifdef PNG_bKGD_SUPPORTED␍␊ |
| 2080 | PNG_EXPORT(131, png_uint_32, png_get_bKGD,␍␊ |
| 2081 | (png_const_structp png_ptr, png_infop info_ptr,␍␊ |
| 2082 | png_color_16p *background));␍␊ |
| 2083 | #endif␍␊ |
| 2084 | ␍␊ |
| 2085 | #ifdef PNG_bKGD_SUPPORTED␍␊ |
| 2086 | PNG_EXPORT(132, void, png_set_bKGD, (png_structp png_ptr, png_infop info_ptr,␍␊ |
| 2087 | png_const_color_16p background));␍␊ |
| 2088 | #endif␍␊ |
| 2089 | ␍␊ |
| 2090 | #ifdef PNG_cHRM_SUPPORTED␍␊ |
| 2091 | PNG_FP_EXPORT(133, png_uint_32, png_get_cHRM, (png_const_structp png_ptr,␍␊ |
| 2092 | png_const_infop info_ptr, double *white_x, double *white_y, double *red_x,␍␊ |
| 2093 | double *red_y, double *green_x, double *green_y, double *blue_x,␍␊ |
| 2094 | double *blue_y))␍␊ |
| 2095 | PNG_FP_EXPORT(230, png_uint_32, png_get_cHRM_XYZ, (png_structp png_ptr,␍␊ |
| 2096 | png_const_infop info_ptr, double *red_X, double *red_Y, double *red_Z,␍␊ |
| 2097 | double *green_X, double *green_Y, double *green_Z, double *blue_X,␍␊ |
| 2098 | double *blue_Y, double *blue_Z))␍␊ |
| 2099 | #ifdef PNG_FIXED_POINT_SUPPORTED /* Otherwise not implemented */␍␊ |
| 2100 | PNG_FIXED_EXPORT(134, png_uint_32, png_get_cHRM_fixed,␍␊ |
| 2101 | (png_const_structp png_ptr,␍␊ |
| 2102 | png_const_infop info_ptr, png_fixed_point *int_white_x,␍␊ |
| 2103 | png_fixed_point *int_white_y, png_fixed_point *int_red_x,␍␊ |
| 2104 | png_fixed_point *int_red_y, png_fixed_point *int_green_x,␍␊ |
| 2105 | png_fixed_point *int_green_y, png_fixed_point *int_blue_x,␍␊ |
| 2106 | png_fixed_point *int_blue_y))␍␊ |
| 2107 | #endif␍␊ |
| 2108 | PNG_FIXED_EXPORT(231, png_uint_32, png_get_cHRM_XYZ_fixed,␍␊ |
| 2109 | (png_structp png_ptr, png_const_infop info_ptr,␍␊ |
| 2110 | png_fixed_point *int_red_X, png_fixed_point *int_red_Y,␍␊ |
| 2111 | png_fixed_point *int_red_Z, png_fixed_point *int_green_X,␍␊ |
| 2112 | png_fixed_point *int_green_Y, png_fixed_point *int_green_Z,␍␊ |
| 2113 | png_fixed_point *int_blue_X, png_fixed_point *int_blue_Y,␍␊ |
| 2114 | png_fixed_point *int_blue_Z))␍␊ |
| 2115 | #endif␍␊ |
| 2116 | ␍␊ |
| 2117 | #ifdef PNG_cHRM_SUPPORTED␍␊ |
| 2118 | PNG_FP_EXPORT(135, void, png_set_cHRM,␍␊ |
| 2119 | (png_structp png_ptr, png_infop info_ptr,␍␊ |
| 2120 | double white_x, double white_y, double red_x, double red_y, double green_x,␍␊ |
| 2121 | double green_y, double blue_x, double blue_y))␍␊ |
| 2122 | PNG_FP_EXPORT(232, void, png_set_cHRM_XYZ, (png_structp png_ptr,␍␊ |
| 2123 | png_infop info_ptr, double red_X, double red_Y, double red_Z,␍␊ |
| 2124 | double green_X, double green_Y, double green_Z, double blue_X,␍␊ |
| 2125 | double blue_Y, double blue_Z))␍␊ |
| 2126 | PNG_FIXED_EXPORT(136, void, png_set_cHRM_fixed, (png_structp png_ptr,␍␊ |
| 2127 | png_infop info_ptr, png_fixed_point int_white_x,␍␊ |
| 2128 | png_fixed_point int_white_y, png_fixed_point int_red_x,␍␊ |
| 2129 | png_fixed_point int_red_y, png_fixed_point int_green_x,␍␊ |
| 2130 | png_fixed_point int_green_y, png_fixed_point int_blue_x,␍␊ |
| 2131 | png_fixed_point int_blue_y))␍␊ |
| 2132 | PNG_FIXED_EXPORT(233, void, png_set_cHRM_XYZ_fixed, (png_structp png_ptr,␍␊ |
| 2133 | png_infop info_ptr, png_fixed_point int_red_X, png_fixed_point int_red_Y,␍␊ |
| 2134 | png_fixed_point int_red_Z, png_fixed_point int_green_X,␍␊ |
| 2135 | png_fixed_point int_green_Y, png_fixed_point int_green_Z,␍␊ |
| 2136 | png_fixed_point int_blue_X, png_fixed_point int_blue_Y,␍␊ |
| 2137 | png_fixed_point int_blue_Z))␍␊ |
| 2138 | #endif␍␊ |
| 2139 | ␍␊ |
| 2140 | #ifdef PNG_gAMA_SUPPORTED␍␊ |
| 2141 | PNG_FP_EXPORT(137, png_uint_32, png_get_gAMA,␍␊ |
| 2142 | (png_const_structp png_ptr, png_const_infop info_ptr,␍␊ |
| 2143 | double *file_gamma))␍␊ |
| 2144 | PNG_FIXED_EXPORT(138, png_uint_32, png_get_gAMA_fixed,␍␊ |
| 2145 | (png_const_structp png_ptr, png_const_infop info_ptr,␍␊ |
| 2146 | png_fixed_point *int_file_gamma))␍␊ |
| 2147 | #endif␍␊ |
| 2148 | ␍␊ |
| 2149 | #ifdef PNG_gAMA_SUPPORTED␍␊ |
| 2150 | PNG_FP_EXPORT(139, void, png_set_gAMA, (png_structp png_ptr,␍␊ |
| 2151 | png_infop info_ptr, double file_gamma))␍␊ |
| 2152 | PNG_FIXED_EXPORT(140, void, png_set_gAMA_fixed, (png_structp png_ptr,␍␊ |
| 2153 | png_infop info_ptr, png_fixed_point int_file_gamma))␍␊ |
| 2154 | #endif␍␊ |
| 2155 | ␍␊ |
| 2156 | #ifdef PNG_hIST_SUPPORTED␍␊ |
| 2157 | PNG_EXPORT(141, png_uint_32, png_get_hIST,␍␊ |
| 2158 | (png_const_structp png_ptr, png_const_infop info_ptr,␍␊ |
| 2159 | png_uint_16p *hist));␍␊ |
| 2160 | #endif␍␊ |
| 2161 | ␍␊ |
| 2162 | #ifdef PNG_hIST_SUPPORTED␍␊ |
| 2163 | PNG_EXPORT(142, void, png_set_hIST, (png_structp png_ptr,␍␊ |
| 2164 | png_infop info_ptr, png_const_uint_16p hist));␍␊ |
| 2165 | #endif␍␊ |
| 2166 | ␍␊ |
| 2167 | PNG_EXPORT(143, png_uint_32, png_get_IHDR,␍␊ |
| 2168 | (png_structp png_ptr, png_infop info_ptr,␍␊ |
| 2169 | png_uint_32 *width, png_uint_32 *height, int *bit_depth, int *color_type,␍␊ |
| 2170 | int *interlace_method, int *compression_method, int *filter_method));␍␊ |
| 2171 | ␍␊ |
| 2172 | PNG_EXPORT(144, void, png_set_IHDR,␍␊ |
| 2173 | (png_structp png_ptr, png_infop info_ptr,␍␊ |
| 2174 | png_uint_32 width, png_uint_32 height, int bit_depth, int color_type,␍␊ |
| 2175 | int interlace_method, int compression_method, int filter_method));␍␊ |
| 2176 | ␍␊ |
| 2177 | #ifdef PNG_oFFs_SUPPORTED␍␊ |
| 2178 | PNG_EXPORT(145, png_uint_32, png_get_oFFs,␍␊ |
| 2179 | (png_const_structp png_ptr, png_const_infop info_ptr,␍␊ |
| 2180 | png_int_32 *offset_x, png_int_32 *offset_y, int *unit_type));␍␊ |
| 2181 | #endif␍␊ |
| 2182 | ␍␊ |
| 2183 | #ifdef PNG_oFFs_SUPPORTED␍␊ |
| 2184 | PNG_EXPORT(146, void, png_set_oFFs,␍␊ |
| 2185 | (png_structp png_ptr, png_infop info_ptr,␍␊ |
| 2186 | png_int_32 offset_x, png_int_32 offset_y, int unit_type));␍␊ |
| 2187 | #endif␍␊ |
| 2188 | ␍␊ |
| 2189 | #ifdef PNG_pCAL_SUPPORTED␍␊ |
| 2190 | PNG_EXPORT(147, png_uint_32, png_get_pCAL,␍␊ |
| 2191 | (png_const_structp png_ptr, png_const_infop info_ptr,␍␊ |
| 2192 | png_charp *purpose, png_int_32 *X0, png_int_32 *X1, int *type,␍␊ |
| 2193 | int *nparams,␍␊ |
| 2194 | png_charp *units, png_charpp *params));␍␊ |
| 2195 | #endif␍␊ |
| 2196 | ␍␊ |
| 2197 | #ifdef PNG_pCAL_SUPPORTED␍␊ |
| 2198 | PNG_EXPORT(148, void, png_set_pCAL, (png_structp png_ptr,␍␊ |
| 2199 | png_infop info_ptr,␍␊ |
| 2200 | png_const_charp purpose, png_int_32 X0, png_int_32 X1, int type,␍␊ |
| 2201 | int nparams, png_const_charp units, png_charpp params));␍␊ |
| 2202 | #endif␍␊ |
| 2203 | ␍␊ |
| 2204 | #ifdef PNG_pHYs_SUPPORTED␍␊ |
| 2205 | PNG_EXPORT(149, png_uint_32, png_get_pHYs,␍␊ |
| 2206 | (png_const_structp png_ptr, png_const_infop info_ptr,␍␊ |
| 2207 | png_uint_32 *res_x, png_uint_32 *res_y, int *unit_type));␍␊ |
| 2208 | #endif␍␊ |
| 2209 | ␍␊ |
| 2210 | #ifdef PNG_pHYs_SUPPORTED␍␊ |
| 2211 | PNG_EXPORT(150, void, png_set_pHYs,␍␊ |
| 2212 | (png_structp png_ptr, png_infop info_ptr,␍␊ |
| 2213 | png_uint_32 res_x, png_uint_32 res_y, int unit_type));␍␊ |
| 2214 | #endif␍␊ |
| 2215 | ␍␊ |
| 2216 | PNG_EXPORT(151, png_uint_32, png_get_PLTE,␍␊ |
| 2217 | (png_const_structp png_ptr, png_const_infop info_ptr,␍␊ |
| 2218 | png_colorp *palette, int *num_palette));␍␊ |
| 2219 | ␍␊ |
| 2220 | PNG_EXPORT(152, void, png_set_PLTE,␍␊ |
| 2221 | (png_structp png_ptr, png_infop info_ptr,␍␊ |
| 2222 | png_const_colorp palette, int num_palette));␍␊ |
| 2223 | ␍␊ |
| 2224 | #ifdef PNG_sBIT_SUPPORTED␍␊ |
| 2225 | PNG_EXPORT(153, png_uint_32, png_get_sBIT,␍␊ |
| 2226 | (png_const_structp png_ptr, png_infop info_ptr,␍␊ |
| 2227 | png_color_8p *sig_bit));␍␊ |
| 2228 | #endif␍␊ |
| 2229 | ␍␊ |
| 2230 | #ifdef PNG_sBIT_SUPPORTED␍␊ |
| 2231 | PNG_EXPORT(154, void, png_set_sBIT,␍␊ |
| 2232 | (png_structp png_ptr, png_infop info_ptr, png_const_color_8p sig_bit));␍␊ |
| 2233 | #endif␍␊ |
| 2234 | ␍␊ |
| 2235 | #ifdef PNG_sRGB_SUPPORTED␍␊ |
| 2236 | PNG_EXPORT(155, png_uint_32, png_get_sRGB, (png_const_structp png_ptr,␍␊ |
| 2237 | png_const_infop info_ptr, int *file_srgb_intent));␍␊ |
| 2238 | #endif␍␊ |
| 2239 | ␍␊ |
| 2240 | #ifdef PNG_sRGB_SUPPORTED␍␊ |
| 2241 | PNG_EXPORT(156, void, png_set_sRGB,␍␊ |
| 2242 | (png_structp png_ptr, png_infop info_ptr, int srgb_intent));␍␊ |
| 2243 | PNG_EXPORT(157, void, png_set_sRGB_gAMA_and_cHRM, (png_structp png_ptr,␍␊ |
| 2244 | png_infop info_ptr, int srgb_intent));␍␊ |
| 2245 | #endif␍␊ |
| 2246 | ␍␊ |
| 2247 | #ifdef PNG_iCCP_SUPPORTED␍␊ |
| 2248 | PNG_EXPORT(158, png_uint_32, png_get_iCCP,␍␊ |
| 2249 | (png_const_structp png_ptr, png_const_infop info_ptr,␍␊ |
| 2250 | png_charpp name, int *compression_type, png_bytepp profile,␍␊ |
| 2251 | png_uint_32 *proflen));␍␊ |
| 2252 | #endif␍␊ |
| 2253 | ␍␊ |
| 2254 | #ifdef PNG_iCCP_SUPPORTED␍␊ |
| 2255 | PNG_EXPORT(159, void, png_set_iCCP,␍␊ |
| 2256 | (png_structp png_ptr, png_infop info_ptr,␍␊ |
| 2257 | png_const_charp name, int compression_type, png_const_bytep profile,␍␊ |
| 2258 | png_uint_32 proflen));␍␊ |
| 2259 | #endif␍␊ |
| 2260 | ␍␊ |
| 2261 | #ifdef PNG_sPLT_SUPPORTED␍␊ |
| 2262 | PNG_EXPORT(160, png_uint_32, png_get_sPLT,␍␊ |
| 2263 | (png_const_structp png_ptr, png_const_infop info_ptr,␍␊ |
| 2264 | png_sPLT_tpp entries));␍␊ |
| 2265 | #endif␍␊ |
| 2266 | ␍␊ |
| 2267 | #ifdef PNG_sPLT_SUPPORTED␍␊ |
| 2268 | PNG_EXPORT(161, void, png_set_sPLT,␍␊ |
| 2269 | (png_structp png_ptr, png_infop info_ptr,␍␊ |
| 2270 | png_const_sPLT_tp entries, int nentries));␍␊ |
| 2271 | #endif␍␊ |
| 2272 | ␍␊ |
| 2273 | #ifdef PNG_TEXT_SUPPORTED␍␊ |
| 2274 | /* png_get_text also returns the number of text chunks in *num_text */␍␊ |
| 2275 | PNG_EXPORT(162, png_uint_32, png_get_text,␍␊ |
| 2276 | (png_const_structp png_ptr, png_const_infop info_ptr,␍␊ |
| 2277 | png_textp *text_ptr, int *num_text));␍␊ |
| 2278 | #endif␍␊ |
| 2279 | ␍␊ |
| 2280 | /* Note while png_set_text() will accept a structure whose text,␍␊ |
| 2281 | * language, and translated keywords are NULL pointers, the structure␍␊ |
| 2282 | * returned by png_get_text will always contain regular␍␊ |
| 2283 | * zero-terminated C strings. They might be empty strings but␍␊ |
| 2284 | * they will never be NULL pointers.␍␊ |
| 2285 | */␍␊ |
| 2286 | ␍␊ |
| 2287 | #ifdef PNG_TEXT_SUPPORTED␍␊ |
| 2288 | PNG_EXPORT(163, void, png_set_text,␍␊ |
| 2289 | (png_structp png_ptr, png_infop info_ptr,␍␊ |
| 2290 | png_const_textp text_ptr, int num_text));␍␊ |
| 2291 | #endif␍␊ |
| 2292 | ␍␊ |
| 2293 | #ifdef PNG_tIME_SUPPORTED␍␊ |
| 2294 | PNG_EXPORT(164, png_uint_32, png_get_tIME,␍␊ |
| 2295 | (png_const_structp png_ptr, png_infop info_ptr, png_timep *mod_time));␍␊ |
| 2296 | #endif␍␊ |
| 2297 | ␍␊ |
| 2298 | #ifdef PNG_tIME_SUPPORTED␍␊ |
| 2299 | PNG_EXPORT(165, void, png_set_tIME,␍␊ |
| 2300 | (png_structp png_ptr, png_infop info_ptr, png_const_timep mod_time));␍␊ |
| 2301 | #endif␍␊ |
| 2302 | ␍␊ |
| 2303 | #ifdef PNG_tRNS_SUPPORTED␍␊ |
| 2304 | PNG_EXPORT(166, png_uint_32, png_get_tRNS,␍␊ |
| 2305 | (png_const_structp png_ptr, png_infop info_ptr,␍␊ |
| 2306 | png_bytep *trans_alpha, int *num_trans, png_color_16p *trans_color));␍␊ |
| 2307 | #endif␍␊ |
| 2308 | ␍␊ |
| 2309 | #ifdef PNG_tRNS_SUPPORTED␍␊ |
| 2310 | PNG_EXPORT(167, void, png_set_tRNS,␍␊ |
| 2311 | (png_structp png_ptr, png_infop info_ptr,␍␊ |
| 2312 | png_const_bytep trans_alpha, int num_trans,␍␊ |
| 2313 | png_const_color_16p trans_color));␍␊ |
| 2314 | #endif␍␊ |
| 2315 | ␍␊ |
| 2316 | #ifdef PNG_sCAL_SUPPORTED␍␊ |
| 2317 | PNG_FP_EXPORT(168, png_uint_32, png_get_sCAL,␍␊ |
| 2318 | (png_const_structp png_ptr, png_const_infop info_ptr,␍␊ |
| 2319 | int *unit, double *width, double *height))␍␊ |
| 2320 | #ifdef PNG_FLOATING_ARITHMETIC_SUPPORTED␍␊ |
| 2321 | /* NOTE: this API is currently implemented using floating point arithmetic,␍␊ |
| 2322 | * consequently it can only be used on systems with floating point support.␍␊ |
| 2323 | * In any case the range of values supported by png_fixed_point is small and it␍␊ |
| 2324 | * is highly recommended that png_get_sCAL_s be used instead.␍␊ |
| 2325 | */␍␊ |
| 2326 | PNG_FIXED_EXPORT(214, png_uint_32, png_get_sCAL_fixed,␍␊ |
| 2327 | (png_structp png_ptr, png_const_infop info_ptr, int *unit,␍␊ |
| 2328 | png_fixed_point *width,␍␊ |
| 2329 | png_fixed_point *height))␍␊ |
| 2330 | #endif␍␊ |
| 2331 | PNG_EXPORT(169, png_uint_32, png_get_sCAL_s,␍␊ |
| 2332 | (png_const_structp png_ptr, png_const_infop info_ptr,␍␊ |
| 2333 | int *unit, png_charpp swidth, png_charpp sheight));␍␊ |
| 2334 | ␍␊ |
| 2335 | PNG_FP_EXPORT(170, void, png_set_sCAL,␍␊ |
| 2336 | (png_structp png_ptr, png_infop info_ptr,␍␊ |
| 2337 | int unit, double width, double height))␍␊ |
| 2338 | PNG_FIXED_EXPORT(213, void, png_set_sCAL_fixed, (png_structp png_ptr,␍␊ |
| 2339 | png_infop info_ptr, int unit, png_fixed_point width,␍␊ |
| 2340 | png_fixed_point height))␍␊ |
| 2341 | PNG_EXPORT(171, void, png_set_sCAL_s,␍␊ |
| 2342 | (png_structp png_ptr, png_infop info_ptr,␍␊ |
| 2343 | int unit, png_const_charp swidth, png_const_charp sheight));␍␊ |
| 2344 | #endif /* PNG_sCAL_SUPPORTED */␍␊ |
| 2345 | ␍␊ |
| 2346 | #ifdef PNG_HANDLE_AS_UNKNOWN_SUPPORTED␍␊ |
| 2347 | /* Provide a list of chunks and how they are to be handled, if the built-in␍␊ |
| 2348 | handling or default unknown chunk handling is not desired. Any chunks not␍␊ |
| 2349 | listed will be handled in the default manner. The IHDR and IEND chunks␍␊ |
| 2350 | must not be listed. Because this turns off the default handling for chunks␍␊ |
| 2351 | that would otherwise be recognized the behavior of libpng transformations may␍␊ |
| 2352 | well become incorrect!␍␊ |
| 2353 | keep = 0: PNG_HANDLE_CHUNK_AS_DEFAULT: follow default behavior␍␊ |
| 2354 | = 1: PNG_HANDLE_CHUNK_NEVER: do not keep␍␊ |
| 2355 | = 2: PNG_HANDLE_CHUNK_IF_SAFE: keep only if safe-to-copy␍␊ |
| 2356 | = 3: PNG_HANDLE_CHUNK_ALWAYS: keep even if unsafe-to-copy␍␊ |
| 2357 | */␍␊ |
| 2358 | PNG_EXPORT(172, void, png_set_keep_unknown_chunks,␍␊ |
| 2359 | (png_structp png_ptr, int keep,␍␊ |
| 2360 | png_const_bytep chunk_list, int num_chunks));␍␊ |
| 2361 | ␍␊ |
| 2362 | /* The handling code is returned; the result is therefore true (non-zero) if␍␊ |
| 2363 | * special handling is required, false for the default handling.␍␊ |
| 2364 | */␍␊ |
| 2365 | PNG_EXPORT(173, int, png_handle_as_unknown, (png_structp png_ptr,␍␊ |
| 2366 | png_const_bytep chunk_name));␍␊ |
| 2367 | #endif␍␊ |
| 2368 | #ifdef PNG_UNKNOWN_CHUNKS_SUPPORTED␍␊ |
| 2369 | PNG_EXPORT(174, void, png_set_unknown_chunks, (png_structp png_ptr,␍␊ |
| 2370 | png_infop info_ptr, png_const_unknown_chunkp unknowns,␍␊ |
| 2371 | int num_unknowns));␍␊ |
| 2372 | PNG_EXPORT(175, void, png_set_unknown_chunk_location,␍␊ |
| 2373 | (png_structp png_ptr, png_infop info_ptr, int chunk, int location));␍␊ |
| 2374 | PNG_EXPORT(176, int, png_get_unknown_chunks, (png_const_structp png_ptr,␍␊ |
| 2375 | png_const_infop info_ptr, png_unknown_chunkpp entries));␍␊ |
| 2376 | #endif␍␊ |
| 2377 | ␍␊ |
| 2378 | /* Png_free_data() will turn off the "valid" flag for anything it frees.␍␊ |
| 2379 | * If you need to turn it off for a chunk that your application has freed,␍␊ |
| 2380 | * you can use png_set_invalid(png_ptr, info_ptr, PNG_INFO_CHNK);␍␊ |
| 2381 | */␍␊ |
| 2382 | PNG_EXPORT(177, void, png_set_invalid,␍␊ |
| 2383 | (png_structp png_ptr, png_infop info_ptr, int mask));␍␊ |
| 2384 | ␍␊ |
| 2385 | #ifdef PNG_INFO_IMAGE_SUPPORTED␍␊ |
| 2386 | /* The "params" pointer is currently not used and is for future expansion. */␍␊ |
| 2387 | PNG_EXPORT(178, void, png_read_png, (png_structp png_ptr, png_infop info_ptr,␍␊ |
| 2388 | int transforms, png_voidp params));␍␊ |
| 2389 | PNG_EXPORT(179, void, png_write_png, (png_structp png_ptr, png_infop info_ptr,␍␊ |
| 2390 | int transforms, png_voidp params));␍␊ |
| 2391 | #endif␍␊ |
| 2392 | ␍␊ |
| 2393 | PNG_EXPORT(180, png_const_charp, png_get_copyright,␍␊ |
| 2394 | (png_const_structp png_ptr));␍␊ |
| 2395 | PNG_EXPORT(181, png_const_charp, png_get_header_ver,␍␊ |
| 2396 | (png_const_structp png_ptr));␍␊ |
| 2397 | PNG_EXPORT(182, png_const_charp, png_get_header_version,␍␊ |
| 2398 | (png_const_structp png_ptr));␍␊ |
| 2399 | PNG_EXPORT(183, png_const_charp, png_get_libpng_ver,␍␊ |
| 2400 | (png_const_structp png_ptr));␍␊ |
| 2401 | ␍␊ |
| 2402 | #ifdef PNG_MNG_FEATURES_SUPPORTED␍␊ |
| 2403 | PNG_EXPORT(184, png_uint_32, png_permit_mng_features, (png_structp png_ptr,␍␊ |
| 2404 | png_uint_32 mng_features_permitted));␍␊ |
| 2405 | #endif␍␊ |
| 2406 | ␍␊ |
| 2407 | /* For use in png_set_keep_unknown, added to version 1.2.6 */␍␊ |
| 2408 | #define PNG_HANDLE_CHUNK_AS_DEFAULT 0␍␊ |
| 2409 | #define PNG_HANDLE_CHUNK_NEVER 1␍␊ |
| 2410 | #define PNG_HANDLE_CHUNK_IF_SAFE 2␍␊ |
| 2411 | #define PNG_HANDLE_CHUNK_ALWAYS 3␍␊ |
| 2412 | ␍␊ |
| 2413 | /* Strip the prepended error numbers ("#nnn ") from error and warning␍␊ |
| 2414 | * messages before passing them to the error or warning handler.␍␊ |
| 2415 | */␍␊ |
| 2416 | #ifdef PNG_ERROR_NUMBERS_SUPPORTED␍␊ |
| 2417 | PNG_EXPORT(185, void, png_set_strip_error_numbers,␍␊ |
| 2418 | (png_structp png_ptr,␍␊ |
| 2419 | png_uint_32 strip_mode));␍␊ |
| 2420 | #endif␍␊ |
| 2421 | ␍␊ |
| 2422 | /* Added in libpng-1.2.6 */␍␊ |
| 2423 | #ifdef PNG_SET_USER_LIMITS_SUPPORTED␍␊ |
| 2424 | PNG_EXPORT(186, void, png_set_user_limits, (png_structp png_ptr,␍␊ |
| 2425 | png_uint_32 user_width_max, png_uint_32 user_height_max));␍␊ |
| 2426 | PNG_EXPORT(187, png_uint_32, png_get_user_width_max,␍␊ |
| 2427 | (png_const_structp png_ptr));␍␊ |
| 2428 | PNG_EXPORT(188, png_uint_32, png_get_user_height_max,␍␊ |
| 2429 | (png_const_structp png_ptr));␍␊ |
| 2430 | /* Added in libpng-1.4.0 */␍␊ |
| 2431 | PNG_EXPORT(189, void, png_set_chunk_cache_max, (png_structp png_ptr,␍␊ |
| 2432 | png_uint_32 user_chunk_cache_max));␍␊ |
| 2433 | PNG_EXPORT(190, png_uint_32, png_get_chunk_cache_max,␍␊ |
| 2434 | (png_const_structp png_ptr));␍␊ |
| 2435 | /* Added in libpng-1.4.1 */␍␊ |
| 2436 | PNG_EXPORT(191, void, png_set_chunk_malloc_max, (png_structp png_ptr,␍␊ |
| 2437 | png_alloc_size_t user_chunk_cache_max));␍␊ |
| 2438 | PNG_EXPORT(192, png_alloc_size_t, png_get_chunk_malloc_max,␍␊ |
| 2439 | (png_const_structp png_ptr));␍␊ |
| 2440 | #endif␍␊ |
| 2441 | ␍␊ |
| 2442 | #if defined(PNG_INCH_CONVERSIONS_SUPPORTED)␍␊ |
| 2443 | PNG_EXPORT(193, png_uint_32, png_get_pixels_per_inch,␍␊ |
| 2444 | (png_const_structp png_ptr, png_const_infop info_ptr));␍␊ |
| 2445 | ␍␊ |
| 2446 | PNG_EXPORT(194, png_uint_32, png_get_x_pixels_per_inch,␍␊ |
| 2447 | (png_const_structp png_ptr, png_const_infop info_ptr));␍␊ |
| 2448 | ␍␊ |
| 2449 | PNG_EXPORT(195, png_uint_32, png_get_y_pixels_per_inch,␍␊ |
| 2450 | (png_const_structp png_ptr, png_const_infop info_ptr));␍␊ |
| 2451 | ␍␊ |
| 2452 | PNG_FP_EXPORT(196, float, png_get_x_offset_inches,␍␊ |
| 2453 | (png_const_structp png_ptr, png_const_infop info_ptr))␍␊ |
| 2454 | #ifdef PNG_FIXED_POINT_SUPPORTED /* otherwise not implemented. */␍␊ |
| 2455 | PNG_FIXED_EXPORT(211, png_fixed_point, png_get_x_offset_inches_fixed,␍␊ |
| 2456 | (png_structp png_ptr, png_const_infop info_ptr))␍␊ |
| 2457 | #endif␍␊ |
| 2458 | ␍␊ |
| 2459 | PNG_FP_EXPORT(197, float, png_get_y_offset_inches, (png_const_structp png_ptr,␍␊ |
| 2460 | png_const_infop info_ptr))␍␊ |
| 2461 | #ifdef PNG_FIXED_POINT_SUPPORTED /* otherwise not implemented. */␍␊ |
| 2462 | PNG_FIXED_EXPORT(212, png_fixed_point, png_get_y_offset_inches_fixed,␍␊ |
| 2463 | (png_structp png_ptr, png_const_infop info_ptr))␍␊ |
| 2464 | #endif␍␊ |
| 2465 | ␍␊ |
| 2466 | # ifdef PNG_pHYs_SUPPORTED␍␊ |
| 2467 | PNG_EXPORT(198, png_uint_32, png_get_pHYs_dpi, (png_const_structp png_ptr,␍␊ |
| 2468 | png_const_infop info_ptr, png_uint_32 *res_x, png_uint_32 *res_y,␍␊ |
| 2469 | int *unit_type));␍␊ |
| 2470 | # endif /* PNG_pHYs_SUPPORTED */␍␊ |
| 2471 | #endif /* PNG_INCH_CONVERSIONS_SUPPORTED */␍␊ |
| 2472 | ␍␊ |
| 2473 | /* Added in libpng-1.4.0 */␍␊ |
| 2474 | #ifdef PNG_IO_STATE_SUPPORTED␍␊ |
| 2475 | PNG_EXPORT(199, png_uint_32, png_get_io_state, (png_structp png_ptr));␍␊ |
| 2476 | ␍␊ |
| 2477 | PNG_EXPORTA(200, png_const_bytep, png_get_io_chunk_name,␍␊ |
| 2478 | (png_structp png_ptr), PNG_DEPRECATED);␍␊ |
| 2479 | PNG_EXPORT(216, png_uint_32, png_get_io_chunk_type,␍␊ |
| 2480 | (png_const_structp png_ptr));␍␊ |
| 2481 | ␍␊ |
| 2482 | /* The flags returned by png_get_io_state() are the following: */␍␊ |
| 2483 | # define PNG_IO_NONE 0x0000 /* no I/O at this moment */␍␊ |
| 2484 | # define PNG_IO_READING 0x0001 /* currently reading */␍␊ |
| 2485 | # define PNG_IO_WRITING 0x0002 /* currently writing */␍␊ |
| 2486 | # define PNG_IO_SIGNATURE 0x0010 /* currently at the file signature */␍␊ |
| 2487 | # define PNG_IO_CHUNK_HDR 0x0020 /* currently at the chunk header */␍␊ |
| 2488 | # define PNG_IO_CHUNK_DATA 0x0040 /* currently at the chunk data */␍␊ |
| 2489 | # define PNG_IO_CHUNK_CRC 0x0080 /* currently at the chunk crc */␍␊ |
| 2490 | # define PNG_IO_MASK_OP 0x000f /* current operation: reading/writing */␍␊ |
| 2491 | # define PNG_IO_MASK_LOC 0x00f0 /* current location: sig/hdr/data/crc */␍␊ |
| 2492 | #endif /* ?PNG_IO_STATE_SUPPORTED */␍␊ |
| 2493 | ␍␊ |
| 2494 | /* Interlace support. The following macros are always defined so that if␍␊ |
| 2495 | * libpng interlace handling is turned off the macros may be used to handle␍␊ |
| 2496 | * interlaced images within the application.␍␊ |
| 2497 | */␍␊ |
| 2498 | #define PNG_INTERLACE_ADAM7_PASSES 7␍␊ |
| 2499 | ␍␊ |
| 2500 | /* Two macros to return the first row and first column of the original,␍␊ |
| 2501 | * full, image which appears in a given pass. 'pass' is in the range 0␍␊ |
| 2502 | * to 6 and the result is in the range 0 to 7.␍␊ |
| 2503 | */␍␊ |
| 2504 | #define PNG_PASS_START_ROW(pass) (((1&~(pass))<<(3-((pass)>>1)))&7)␍␊ |
| 2505 | #define PNG_PASS_START_COL(pass) (((1& (pass))<<(3-(((pass)+1)>>1)))&7)␍␊ |
| 2506 | ␍␊ |
| 2507 | /* A macro to return the offset between pixels in the output row for a pair of␍␊ |
| 2508 | * pixels in the input - effectively the inverse of the 'COL_SHIFT' macro that␍␊ |
| 2509 | * follows. Note that ROW_OFFSET is the offset from one row to the next whereas␍␊ |
| 2510 | * COL_OFFSET is from one column to the next, within a row.␍␊ |
| 2511 | */␍␊ |
| 2512 | #define PNG_PASS_ROW_OFFSET(pass) ((pass)>2?(8>>(((pass)-1)>>1)):8)␍␊ |
| 2513 | #define PNG_PASS_COL_OFFSET(pass) (1<<((7-(pass))>>1))␍␊ |
| 2514 | ␍␊ |
| 2515 | /* Two macros to help evaluate the number of rows or columns in each␍␊ |
| 2516 | * pass. This is expressed as a shift - effectively log2 of the number or␍␊ |
| 2517 | * rows or columns in each 8x8 tile of the original image.␍␊ |
| 2518 | */␍␊ |
| 2519 | #define PNG_PASS_ROW_SHIFT(pass) ((pass)>2?(8-(pass))>>1:3)␍␊ |
| 2520 | #define PNG_PASS_COL_SHIFT(pass) ((pass)>1?(7-(pass))>>1:3)␍␊ |
| 2521 | ␍␊ |
| 2522 | /* Hence two macros to determine the number of rows or columns in a given␍␊ |
| 2523 | * pass of an image given its height or width. In fact these macros may␍␊ |
| 2524 | * return non-zero even though the sub-image is empty, because the other␍␊ |
| 2525 | * dimension may be empty for a small image.␍␊ |
| 2526 | */␍␊ |
| 2527 | #define PNG_PASS_ROWS(height, pass) (((height)+(((1<<PNG_PASS_ROW_SHIFT(pass))\␍␊ |
| 2528 | -1)-PNG_PASS_START_ROW(pass)))>>PNG_PASS_ROW_SHIFT(pass))␍␊ |
| 2529 | #define PNG_PASS_COLS(width, pass) (((width)+(((1<<PNG_PASS_COL_SHIFT(pass))\␍␊ |
| 2530 | -1)-PNG_PASS_START_COL(pass)))>>PNG_PASS_COL_SHIFT(pass))␍␊ |
| 2531 | ␍␊ |
| 2532 | /* For the reader row callbacks (both progressive and sequential) it is␍␊ |
| 2533 | * necessary to find the row in the output image given a row in an interlaced␍␊ |
| 2534 | * image, so two more macros:␍␊ |
| 2535 | */␍␊ |
| 2536 | #define PNG_ROW_FROM_PASS_ROW(yIn, pass) \␍␊ |
| 2537 | (((yIn)<<PNG_PASS_ROW_SHIFT(pass))+PNG_PASS_START_ROW(pass))␍␊ |
| 2538 | #define PNG_COL_FROM_PASS_COL(xIn, pass) \␍␊ |
| 2539 | (((xIn)<<PNG_PASS_COL_SHIFT(pass))+PNG_PASS_START_COL(pass))␍␊ |
| 2540 | ␍␊ |
| 2541 | /* Two macros which return a boolean (0 or 1) saying whether the given row␍␊ |
| 2542 | * or column is in a particular pass. These use a common utility macro that␍␊ |
| 2543 | * returns a mask for a given pass - the offset 'off' selects the row or␍␊ |
| 2544 | * column version. The mask has the appropriate bit set for each column in␍␊ |
| 2545 | * the tile.␍␊ |
| 2546 | */␍␊ |
| 2547 | #define PNG_PASS_MASK(pass,off) ( \␍␊ |
| 2548 | ((0x110145AF>>(((7-(off))-(pass))<<2)) & 0xF) | \␍␊ |
| 2549 | ((0x01145AF0>>(((7-(off))-(pass))<<2)) & 0xF0))␍␊ |
| 2550 | ␍␊ |
| 2551 | #define PNG_ROW_IN_INTERLACE_PASS(y, pass) \␍␊ |
| 2552 | ((PNG_PASS_MASK(pass,0) >> ((y)&7)) & 1)␍␊ |
| 2553 | #define PNG_COL_IN_INTERLACE_PASS(x, pass) \␍␊ |
| 2554 | ((PNG_PASS_MASK(pass,1) >> ((x)&7)) & 1)␍␊ |
| 2555 | ␍␊ |
| 2556 | #ifdef PNG_READ_COMPOSITE_NODIV_SUPPORTED␍␊ |
| 2557 | /* With these routines we avoid an integer divide, which will be slower on␍␊ |
| 2558 | * most machines. However, it does take more operations than the corresponding␍␊ |
| 2559 | * divide method, so it may be slower on a few RISC systems. There are two␍␊ |
| 2560 | * shifts (by 8 or 16 bits) and an addition, versus a single integer divide.␍␊ |
| 2561 | *␍␊ |
| 2562 | * Note that the rounding factors are NOT supposed to be the same! 128 and␍␊ |
| 2563 | * 32768 are correct for the NODIV code; 127 and 32767 are correct for the␍␊ |
| 2564 | * standard method.␍␊ |
| 2565 | *␍␊ |
| 2566 | * [Optimized code by Greg Roelofs and Mark Adler...blame us for bugs. :-) ]␍␊ |
| 2567 | */␍␊ |
| 2568 | ␍␊ |
| 2569 | /* fg and bg should be in `gamma 1.0' space; alpha is the opacity */␍␊ |
| 2570 | ␍␊ |
| 2571 | # define png_composite(composite, fg, alpha, bg) \␍␊ |
| 2572 | { png_uint_16 temp = (png_uint_16)((png_uint_16)(fg) \␍␊ |
| 2573 | * (png_uint_16)(alpha) \␍␊ |
| 2574 | + (png_uint_16)(bg)*(png_uint_16)(255 \␍␊ |
| 2575 | - (png_uint_16)(alpha)) + 128); \␍␊ |
| 2576 | (composite) = (png_byte)((temp + (temp >> 8)) >> 8); }␍␊ |
| 2577 | ␍␊ |
| 2578 | # define png_composite_16(composite, fg, alpha, bg) \␍␊ |
| 2579 | { png_uint_32 temp = (png_uint_32)((png_uint_32)(fg) \␍␊ |
| 2580 | * (png_uint_32)(alpha) \␍␊ |
| 2581 | + (png_uint_32)(bg)*(65535 \␍␊ |
| 2582 | - (png_uint_32)(alpha)) + 32768); \␍␊ |
| 2583 | (composite) = (png_uint_16)((temp + (temp >> 16)) >> 16); }␍␊ |
| 2584 | ␍␊ |
| 2585 | #else /* Standard method using integer division */␍␊ |
| 2586 | ␍␊ |
| 2587 | # define png_composite(composite, fg, alpha, bg) \␍␊ |
| 2588 | (composite) = (png_byte)(((png_uint_16)(fg) * (png_uint_16)(alpha) + \␍␊ |
| 2589 | (png_uint_16)(bg) * (png_uint_16)(255 - (png_uint_16)(alpha)) + \␍␊ |
| 2590 | 127) / 255)␍␊ |
| 2591 | ␍␊ |
| 2592 | # define png_composite_16(composite, fg, alpha, bg) \␍␊ |
| 2593 | (composite) = (png_uint_16)(((png_uint_32)(fg) * (png_uint_32)(alpha) + \␍␊ |
| 2594 | (png_uint_32)(bg)*(png_uint_32)(65535 - (png_uint_32)(alpha)) + \␍␊ |
| 2595 | 32767) / 65535)␍␊ |
| 2596 | #endif /* PNG_READ_COMPOSITE_NODIV_SUPPORTED */␍␊ |
| 2597 | ␍␊ |
| 2598 | #ifdef PNG_READ_INT_FUNCTIONS_SUPPORTED␍␊ |
| 2599 | PNG_EXPORT(201, png_uint_32, png_get_uint_32, (png_const_bytep buf));␍␊ |
| 2600 | PNG_EXPORT(202, png_uint_16, png_get_uint_16, (png_const_bytep buf));␍␊ |
| 2601 | PNG_EXPORT(203, png_int_32, png_get_int_32, (png_const_bytep buf));␍␊ |
| 2602 | #endif␍␊ |
| 2603 | ␍␊ |
| 2604 | PNG_EXPORT(204, png_uint_32, png_get_uint_31, (png_structp png_ptr,␍␊ |
| 2605 | png_const_bytep buf));␍␊ |
| 2606 | /* No png_get_int_16 -- may be added if there's a real need for it. */␍␊ |
| 2607 | ␍␊ |
| 2608 | /* Place a 32-bit number into a buffer in PNG byte order (big-endian). */␍␊ |
| 2609 | #ifdef PNG_WRITE_INT_FUNCTIONS_SUPPORTED␍␊ |
| 2610 | PNG_EXPORT(205, void, png_save_uint_32, (png_bytep buf, png_uint_32 i));␍␊ |
| 2611 | #endif␍␊ |
| 2612 | #ifdef PNG_SAVE_INT_32_SUPPORTED␍␊ |
| 2613 | PNG_EXPORT(206, void, png_save_int_32, (png_bytep buf, png_int_32 i));␍␊ |
| 2614 | #endif␍␊ |
| 2615 | ␍␊ |
| 2616 | /* Place a 16-bit number into a buffer in PNG byte order.␍␊ |
| 2617 | * The parameter is declared unsigned int, not png_uint_16,␍␊ |
| 2618 | * just to avoid potential problems on pre-ANSI C compilers.␍␊ |
| 2619 | */␍␊ |
| 2620 | #ifdef PNG_WRITE_INT_FUNCTIONS_SUPPORTED␍␊ |
| 2621 | PNG_EXPORT(207, void, png_save_uint_16, (png_bytep buf, unsigned int i));␍␊ |
| 2622 | /* No png_save_int_16 -- may be added if there's a real need for it. */␍␊ |
| 2623 | #endif␍␊ |
| 2624 | ␍␊ |
| 2625 | #ifdef PNG_USE_READ_MACROS␍␊ |
| 2626 | /* Inline macros to do direct reads of bytes from the input buffer.␍␊ |
| 2627 | * The png_get_int_32() routine assumes we are using two's complement␍␊ |
| 2628 | * format for negative values, which is almost certainly true.␍␊ |
| 2629 | */␍␊ |
| 2630 | # define png_get_uint_32(buf) \␍␊ |
| 2631 | (((png_uint_32)(*(buf)) << 24) + \␍␊ |
| 2632 | ((png_uint_32)(*((buf) + 1)) << 16) + \␍␊ |
| 2633 | ((png_uint_32)(*((buf) + 2)) << 8) + \␍␊ |
| 2634 | ((png_uint_32)(*((buf) + 3))))␍␊ |
| 2635 | ␍␊ |
| 2636 | /* From libpng-1.4.0 until 1.4.4, the png_get_uint_16 macro (but not the␍␊ |
| 2637 | * function) incorrectly returned a value of type png_uint_32.␍␊ |
| 2638 | */␍␊ |
| 2639 | # define png_get_uint_16(buf) \␍␊ |
| 2640 | ((png_uint_16) \␍␊ |
| 2641 | (((unsigned int)(*(buf)) << 8) + \␍␊ |
| 2642 | ((unsigned int)(*((buf) + 1)))))␍␊ |
| 2643 | ␍␊ |
| 2644 | # define png_get_int_32(buf) \␍␊ |
| 2645 | ((png_int_32)((*(buf) & 0x80) \␍␊ |
| 2646 | ? -((png_int_32)((png_get_uint_32(buf) ^ 0xffffffffL) + 1)) \␍␊ |
| 2647 | : (png_int_32)png_get_uint_32(buf)))␍␊ |
| 2648 | #endif␍␊ |
| 2649 | ␍␊ |
| 2650 | #if defined(PNG_READ_CHECK_FOR_INVALID_INDEX_SUPPORTED) || \␍␊ |
| 2651 | defined(PNG_WRITE_CHECK_FOR_INVALID_INDEX_SUPPORTED)␍␊ |
| 2652 | PNG_EXPORT(234, void, png_set_check_for_invalid_index, (png_structp png_ptr,␍␊ |
| 2653 | int allowed));␍␊ |
| 2654 | #endif␍␊ |
| 2655 | ␍␊ |
| 2656 | /* Maintainer: Put new public prototypes here ^, in libpng.3, and project␍␊ |
| 2657 | * defs␍␊ |
| 2658 | */␍␊ |
| 2659 | ␍␊ |
| 2660 | /* The last ordinal number (this is the *last* one already used; the next␍␊ |
| 2661 | * one to use is one more than this.) Maintainer, remember to add an entry to␍␊ |
| 2662 | * scripts/symbols.def as well.␍␊ |
| 2663 | */␍␊ |
| 2664 | #ifdef PNG_EXPORT_LAST_ORDINAL␍␊ |
| 2665 | PNG_EXPORT_LAST_ORDINAL(234);␍␊ |
| 2666 | #endif␍␊ |
| 2667 | ␍␊ |
| 2668 | #ifdef __cplusplus␍␊ |
| 2669 | }␍␊ |
| 2670 | #endif␍␊ |
| 2671 | ␍␊ |
| 2672 | #endif /* PNG_VERSION_INFO_ONLY */␍␊ |
| 2673 | /* Do not put anything past this line */␍␊ |
| 2674 | #endif /* PNG_H */␍␊ |
| 2675 | |
