png.h 83.9 KB
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Andreas Dilger 已提交
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/* png.h - header file for PNG reference library
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 *
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 * libpng version 1.5.0beta24 - May 7, 2010
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 * Copyright (c) 1998-2010 Glenn Randers-Pehrson
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 * (Version 0.96 Copyright (c) 1996, 1997 Andreas Dilger)
 * (Version 0.88 Copyright (c) 1995, 1996 Guy Eric Schalnat, Group 42, Inc.)
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 *
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 * This code is released under the libpng license (See LICENSE, below)
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 *
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 * Authors and maintainers:
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 *   libpng versions 0.71, May 1995, through 0.88, January 1996: Guy Schalnat
 *   libpng versions 0.89c, June 1996, through 0.96, May 1997: Andreas Dilger
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 *   libpng versions 0.97, January 1998, through 1.5.0beta24 - May 7, 2010: Glenn
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 *   See also "Contributing Authors", below.
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 *
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 * Note about libpng version numbers:
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 *
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 *   Due to various miscommunications, unforeseen code incompatibilities
 *   and occasional factors outside the authors' control, version numbering
 *   on the library has not always been consistent and straightforward.
 *   The following table summarizes matters since version 0.89c, which was
 *   the first widely used release:
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 *
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 *    source                 png.h  png.h  shared-lib
 *    version                string   int  version
 *    -------                ------ -----  ----------
 *    0.89c "1.0 beta 3"     0.89      89  1.0.89
 *    0.90  "1.0 beta 4"     0.90      90  0.90  [should have been 2.0.90]
 *    0.95  "1.0 beta 5"     0.95      95  0.95  [should have been 2.0.95]
 *    0.96  "1.0 beta 6"     0.96      96  0.96  [should have been 2.0.96]
 *    0.97b "1.00.97 beta 7" 1.00.97   97  1.0.1 [should have been 2.0.97]
 *    0.97c                  0.97      97  2.0.97
 *    0.98                   0.98      98  2.0.98
 *    0.99                   0.99      98  2.0.99
 *    0.99a-m                0.99      99  2.0.99
 *    1.00                   1.00     100  2.1.0 [100 should be 10000]
 *    1.0.0      (from here on, the   100  2.1.0 [100 should be 10000]
 *    1.0.1       png.h string is   10001  2.1.0
 *    1.0.1a-e    identical to the  10002  from here on, the shared library
 *    1.0.2       source version)   10002  is 2.V where V is the source code
 *    1.0.2a-b                      10003  version, except as noted.
 *    1.0.3                         10003
 *    1.0.3a-d                      10004
 *    1.0.4                         10004
 *    1.0.4a-f                      10005
 *    1.0.5 (+ 2 patches)           10005
 *    1.0.5a-d                      10006
 *    1.0.5e-r                      10100 (not source compatible)
 *    1.0.5s-v                      10006 (not binary compatible)
 *    1.0.6 (+ 3 patches)           10006 (still binary incompatible)
 *    1.0.6d-f                      10007 (still binary incompatible)
 *    1.0.6g                        10007
 *    1.0.6h                        10007  10.6h (testing xy.z so-numbering)
 *    1.0.6i                        10007  10.6i
 *    1.0.6j                        10007  2.1.0.6j (incompatible with 1.0.0)
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 *    1.0.7beta11-14        DLLNUM  10007  2.1.0.7beta11-14 (binary compatible)
 *    1.0.7beta15-18           1    10007  2.1.0.7beta15-18 (binary compatible)
 *    1.0.7rc1-2               1    10007  2.1.0.7rc1-2 (binary compatible)
 *    1.0.7                    1    10007  (still compatible)
 *    1.0.8beta1-4             1    10008  2.1.0.8beta1-4
 *    1.0.8rc1                 1    10008  2.1.0.8rc1
 *    1.0.8                    1    10008  2.1.0.8
 *    1.0.9beta1-6             1    10009  2.1.0.9beta1-6
 *    1.0.9rc1                 1    10009  2.1.0.9rc1
 *    1.0.9beta7-10            1    10009  2.1.0.9beta7-10
 *    1.0.9rc2                 1    10009  2.1.0.9rc2
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 *    1.0.9                    1    10009  2.1.0.9
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 *    1.0.10beta1              1    10010  2.1.0.10beta1
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 *    1.0.10rc1                1    10010  2.1.0.10rc1
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 *    1.0.10                   1    10010  2.1.0.10
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 *    1.0.11beta1-3            1    10011  2.1.0.11beta1-3
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 *    1.0.11rc1                1    10011  2.1.0.11rc1
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 *    1.0.11                   1    10011  2.1.0.11
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 *    1.0.12beta1-2            2    10012  2.1.0.12beta1-2
 *    1.0.12rc1                2    10012  2.1.0.12rc1
 *    1.0.12                   2    10012  2.1.0.12
 *    1.1.0a-f                 -    10100  2.1.1.0a-f (branch abandoned)
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 *    1.2.0beta1-2             2    10200  2.1.2.0beta1-2
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 *    1.2.0beta3-5             3    10200  3.1.2.0beta3-5
 *    1.2.0rc1                 3    10200  3.1.2.0rc1
 *    1.2.0                    3    10200  3.1.2.0
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 *    1.2.1beta1-4             3    10201  3.1.2.1beta1-4
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 *    1.2.1rc1-2               3    10201  3.1.2.1rc1-2
 *    1.2.1                    3    10201  3.1.2.1
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 *    1.2.2beta1-6            12    10202  12.so.0.1.2.2beta1-6
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 *    1.0.13beta1             10    10013  10.so.0.1.0.13beta1
 *    1.0.13rc1               10    10013  10.so.0.1.0.13rc1
 *    1.2.2rc1                12    10202  12.so.0.1.2.2rc1
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 *    1.0.13                  10    10013  10.so.0.1.0.13
 *    1.2.2                   12    10202  12.so.0.1.2.2
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 *    1.2.3rc1-6              12    10203  12.so.0.1.2.3rc1-6
 *    1.2.3                   12    10203  12.so.0.1.2.3
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 *    1.2.4beta1-3            13    10204  12.so.0.1.2.4beta1-3
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 *    1.0.14rc1               13    10014  10.so.0.1.0.14rc1
 *    1.2.4rc1                13    10204  12.so.0.1.2.4rc1
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 *    1.0.14                  10    10014  10.so.0.1.0.14
 *    1.2.4                   13    10204  12.so.0.1.2.4
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 *    1.2.5beta1-2            13    10205  12.so.0.1.2.5beta1-2
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 *    1.0.15rc1-3             10    10015  10.so.0.1.0.15rc1-3
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 *    1.2.5rc1-3              13    10205  12.so.0.1.2.5rc1-3
 *    1.0.15                  10    10015  10.so.0.1.0.15
 *    1.2.5                   13    10205  12.so.0.1.2.5
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 *    1.2.6beta1-4            13    10206  12.so.0.1.2.6beta1-4
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 *    1.0.16                  10    10016  10.so.0.1.0.16
 *    1.2.6                   13    10206  12.so.0.1.2.6
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 *    1.2.7beta1-2            13    10207  12.so.0.1.2.7beta1-2
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 *    1.0.17rc1               10    10017  12.so.0.1.0.17rc1
 *    1.2.7rc1                13    10207  12.so.0.1.2.7rc1
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 *    1.0.17                  10    10017  12.so.0.1.0.17
 *    1.2.7                   13    10207  12.so.0.1.2.7
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 *    1.2.8beta1-5            13    10208  12.so.0.1.2.8beta1-5
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 *    1.0.18rc1-5             10    10018  12.so.0.1.0.18rc1-5
 *    1.2.8rc1-5              13    10208  12.so.0.1.2.8rc1-5
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 *    1.0.18                  10    10018  12.so.0.1.0.18
 *    1.2.8                   13    10208  12.so.0.1.2.8
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 *    1.2.9beta1-3            13    10209  12.so.0.1.2.9beta1-3
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 *    1.2.9beta4-11           13    10209  12.so.0.9[.0]
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 *    1.2.9rc1                13    10209  12.so.0.9[.0]
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 *    1.2.9                   13    10209  12.so.0.9[.0]
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 *    1.2.10beta1-7           13    10210  12.so.0.10[.0]
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 *    1.2.10rc1-2             13    10210  12.so.0.10[.0]
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 *    1.2.10                  13    10210  12.so.0.10[.0]
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 *    1.4.0beta1-5            14    10400  14.so.0.0[.0]
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 *    1.2.11beta1-4           13    10211  12.so.0.11[.0]
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 *    1.4.0beta7-8            14    10400  14.so.0.0[.0]
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 *    1.2.11                  13    10211  12.so.0.11[.0]
 *    1.2.12                  13    10212  12.so.0.12[.0]
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 *    1.4.0beta9-14           14    10400  14.so.0.0[.0]
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 *    1.2.13                  13    10213  12.so.0.13[.0]
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 *    1.4.0beta15-36          14    10400  14.so.0.0[.0]
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 *    1.4.0beta37-87          14    10400  14.so.14.0[.0]
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 *    1.4.0rc01               14    10400  14.so.14.0[.0]
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 *    1.4.0beta88-109         14    10400  14.so.14.0[.0]
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 *    1.4.0rc02-08            14    10400  14.so.14.0[.0]
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 *    1.4.0                   14    10400  14.so.14.0[.0]
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 *    1.4.1beta01-03          14    10401  14.so.14.1[.0]
 *    1.4.1rc01               14    10401  14.so.14.1[.0]
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 *    1.4.1beta04-12          14    10401  14.so.14.1[.0]
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 *    1.4.1                   14    10401  14.so.14.1[.0]
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 *    1.5.0beta01-23          15    10500  15.so.15.0[.0]
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 *
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 *   Henceforth the source version will match the shared-library major
 *   and minor numbers; the shared-library major version number will be
 *   used for changes in backward compatibility, as it is intended.  The
 *   PNG_LIBPNG_VER macro, which is not used within libpng but is available
 *   for applications, is an unsigned integer of the form xyyzz corresponding
 *   to the source version x.y.z (leading zeros in y and z).  Beta versions
 *   were given the previous public release number plus a letter, until
 *   version 1.0.6j; from then on they were given the upcoming public
 *   release number plus "betaNN" or "rcN".
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 *
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 *   Binary incompatibility exists only when applications make direct access
 *   to the info_ptr or png_ptr members through png.h, and the compiled
 *   application is loaded with a different version of the library.
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 *
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 *   DLLNUM will change each time there are forward or backward changes
 *   in binary compatibility (e.g., when a new feature is added).
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 *
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 * See libpng.txt or libpng.3 for more information.  The PNG specification
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 * is available as a W3C Recommendation and as an ISO Specification,
 * <http://www.w3.org/TR/2003/REC-PNG-20031110/
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 */

/*
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 * COPYRIGHT NOTICE, DISCLAIMER, and LICENSE:
 *
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 * If you modify libpng you may insert additional notices immediately following
 * this sentence.
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 *
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 * This code is released under the libpng license.
 *
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 * libpng versions 1.2.6, August 15, 2004, through 1.5.0beta24, May 7, 2010, are
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 * Copyright (c) 2004, 2006-2010 Glenn Randers-Pehrson, and are
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 * distributed according to the same disclaimer and license as libpng-1.2.5
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 * with the following individual added to the list of Contributing Authors:
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 *
 *    Cosmin Truta
 *
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 * libpng versions 1.0.7, July 1, 2000, through 1.2.5, October 3, 2002, are
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 * Copyright (c) 2000-2002 Glenn Randers-Pehrson, and are
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 * distributed according to the same disclaimer and license as libpng-1.0.6
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 * with the following individuals added to the list of Contributing Authors:
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 *
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 *    Simon-Pierre Cadieux
 *    Eric S. Raymond
 *    Gilles Vollant
 *
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 * and with the following additions to the disclaimer:
 *
 *    There is no warranty against interference with your enjoyment of the
 *    library or against infringement.  There is no warranty that our
 *    efforts or the library will fulfill any of your particular purposes
 *    or needs.  This library is provided with all faults, and the entire
 *    risk of satisfactory quality, performance, accuracy, and effort is with
 *    the user.
 *
 * libpng versions 0.97, January 1998, through 1.0.6, March 20, 2000, are
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 * Copyright (c) 1998, 1999, 2000 Glenn Randers-Pehrson, and are
 * distributed according to the same disclaimer and license as libpng-0.96,
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 * with the following individuals added to the list of Contributing Authors:
 *
 *    Tom Lane
 *    Glenn Randers-Pehrson
 *    Willem van Schaik
 *
 * libpng versions 0.89, June 1996, through 0.96, May 1997, are
 * Copyright (c) 1996, 1997 Andreas Dilger
 * Distributed according to the same disclaimer and license as libpng-0.88,
 * with the following individuals added to the list of Contributing Authors:
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 *
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 *    John Bowler
 *    Kevin Bracey
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 *    Sam Bushell
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 *    Magnus Holmgren
 *    Greg Roelofs
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 *    Tom Tanner
 *
 * libpng versions 0.5, May 1995, through 0.88, January 1996, are
 * Copyright (c) 1995, 1996 Guy Eric Schalnat, Group 42, Inc.
 *
 * For the purposes of this copyright and license, "Contributing Authors"
 * is defined as the following set of individuals:
 *
 *    Andreas Dilger
 *    Dave Martindale
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 *    Guy Eric Schalnat
 *    Paul Schmidt
 *    Tim Wegner
 *
 * The PNG Reference Library is supplied "AS IS".  The Contributing Authors
 * and Group 42, Inc. disclaim all warranties, expressed or implied,
 * including, without limitation, the warranties of merchantability and of
 * fitness for any purpose.  The Contributing Authors and Group 42, Inc.
 * assume no liability for direct, indirect, incidental, special, exemplary,
 * or consequential damages, which may result from the use of the PNG
 * Reference Library, even if advised of the possibility of such damage.
 *
 * Permission is hereby granted to use, copy, modify, and distribute this
 * source code, or portions hereof, for any purpose, without fee, subject
 * to the following restrictions:
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 *
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 *   1. The origin of this source code must not be misrepresented.
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 *
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 *   2. Altered versions must be plainly marked as such and
 *   must not be misrepresented as being the original source.
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 *
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 *   3. This Copyright notice may not be removed or altered from
 *      any source or altered source distribution.
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 *
 * The Contributing Authors and Group 42, Inc. specifically permit, without
 * fee, and encourage the use of this source code as a component to
 * supporting the PNG file format in commercial products.  If you use this
 * source code in a product, acknowledgment is not required but would be
 * appreciated.
 */
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/*
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 * A "png_get_copyright" function is available, for convenient use in "about"
 * boxes and the like:
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 *
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 *     printf("%s",png_get_copyright(NULL));
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 *
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 * Also, the PNG logo (in PNG format, of course) is supplied in the
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 * files "pngbar.png" and "pngbar.jpg (88x31) and "pngnow.png" (98x31).
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 */

/*
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 * Libpng is OSI Certified Open Source Software.  OSI Certified is a
 * certification mark of the Open Source Initiative.
 */

/*
 * The contributing authors would like to thank all those who helped
 * with testing, bug fixes, and patience.  This wouldn't have been
 * possible without all of you.
 *
 * Thanks to Frank J. T. Wojcik for helping with the documentation.
 */

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/*
 * Y2K compliance in libpng:
 * =========================
 *
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 *    May 7, 2010
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 *
 *    Since the PNG Development group is an ad-hoc body, we can't make
 *    an official declaration.
 *
 *    This is your unofficial assurance that libpng from version 0.71 and
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 *    upward through 1.5.0beta24 are Y2K compliant.  It is my belief that earlier
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 *    versions were also Y2K compliant.
 *
 *    Libpng only has three year fields.  One is a 2-byte unsigned integer
 *    that will hold years up to 65535.  The other two hold the date in text
 *    format, and will hold years up to 9999.
 *
 *    The integer is
 *        "png_uint_16 year" in png_time_struct.
 *
 *    The strings are
 *        "png_charp time_buffer" in png_struct and
 *        "near_time_buffer", which is a local character string in png.c.
 *
 *    There are seven time-related functions:
 *        png.c: png_convert_to_rfc_1123() in png.c
 *          (formerly png_convert_to_rfc_1152() in error)
 *        png_convert_from_struct_tm() in pngwrite.c, called in pngwrite.c
 *        png_convert_from_time_t() in pngwrite.c
 *        png_get_tIME() in pngget.c
 *        png_handle_tIME() in pngrutil.c, called in pngread.c
 *        png_set_tIME() in pngset.c
 *        png_write_tIME() in pngwutil.c, called in pngwrite.c
 *
 *    All handle dates properly in a Y2K environment.  The
 *    png_convert_from_time_t() function calls gmtime() to convert from system
 *    clock time, which returns (year - 1900), which we properly convert to
 *    the full 4-digit year.  There is a possibility that applications using
 *    libpng are not passing 4-digit years into the png_convert_to_rfc_1123()
 *    function, or that they are incorrectly passing only a 2-digit year
 *    instead of "year - 1900" into the png_convert_from_struct_tm() function,
 *    but this is not under our control.  The libpng documentation has always
 *    stated that it works with 4-digit years, and the APIs have been
 *    documented as such.
 *
 *    The tIME chunk itself is also Y2K compliant.  It uses a 2-byte unsigned
 *    integer to hold the year, and can hold years as large as 65535.
 *
 *    zlib, upon which libpng depends, is also Y2K compliant.  It contains
 *    no date-related code.
 *
 *       Glenn Randers-Pehrson
 *       libpng maintainer
 *       PNG Development Group
 */

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#ifndef PNG_H
#define PNG_H
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/* This is not the place to learn how to use libpng.  The file libpng.txt
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 * describes how to use libpng, and the file example.c summarizes it
 * with some code on which to build.  This file is useful for looking
 * at the actual function definitions and structure components.
 */
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/* Version information for png.h - this should match the version in png.c */
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#define PNG_LIBPNG_VER_STRING "1.5.0beta24"
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#define PNG_HEADER_VERSION_STRING \
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     " libpng version 1.5.0beta24 - May 7, 2010\n"
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#define PNG_LIBPNG_VER_SONUM   15
#define PNG_LIBPNG_VER_DLLNUM  15
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/* These should match the first 3 components of PNG_LIBPNG_VER_STRING: */
#define PNG_LIBPNG_VER_MAJOR   1
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#define PNG_LIBPNG_VER_MINOR   5
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#define PNG_LIBPNG_VER_RELEASE 0
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/* This should match the numeric part of the final component of
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 * PNG_LIBPNG_VER_STRING, omitting any leading zero:
 */
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#define PNG_LIBPNG_VER_BUILD  24
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/* Release Status */
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#define PNG_LIBPNG_BUILD_ALPHA    1
#define PNG_LIBPNG_BUILD_BETA     2
#define PNG_LIBPNG_BUILD_RC       3
#define PNG_LIBPNG_BUILD_STABLE   4
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#define PNG_LIBPNG_BUILD_RELEASE_STATUS_MASK 7
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/* Release-Specific Flags */
#define PNG_LIBPNG_BUILD_PATCH    8 /* Can be OR'ed with
                                       PNG_LIBPNG_BUILD_STABLE only */
#define PNG_LIBPNG_BUILD_PRIVATE 16 /* Cannot be OR'ed with
                                       PNG_LIBPNG_BUILD_SPECIAL */
#define PNG_LIBPNG_BUILD_SPECIAL 32 /* Cannot be OR'ed with
                                       PNG_LIBPNG_BUILD_PRIVATE */
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#define PNG_LIBPNG_BUILD_BASE_TYPE PNG_LIBPNG_BUILD_BETA
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/* Careful here.  At one time, Guy wanted to use 082, but that would be octal.
 * We must not include leading zeros.
 * Versions 0.7 through 1.0.0 were in the range 0 to 100 here (only
 * version 1.0.0 was mis-numbered 100 instead of 10000).  From
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 * version 1.0.1 it's    xxyyzz, where x=major, y=minor, z=release
 */
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#define PNG_LIBPNG_VER 10500 /* 1.5.0 */
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/* Library configuration: these options cannot be changed after
 * the library has been built.
 */
#ifndef PNGLCONF_H
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#   include "pnglibconf.h"
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#endif

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#ifndef PNG_VERSION_INFO_ONLY
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/* Standard header files (not needed for the version info) */
#  ifdef PNG_STDIO_SUPPORTED
#    include <stdio.h>
#  endif
#  ifdef PNG_SETJMP_SUPPORTED
#    include <setjmp.h>
#  endif

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/* Include the compression library's header */
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#  include "zlib.h"
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/* Machine specific configuration. */
#  include "pngconf.h"
#endif
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/*
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 * Added at libpng-1.2.8
 *
 * Ref MSDN: Private as priority over Special
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 * VS_FF_PRIVATEBUILD File *was not* built using standard release
 * procedures. If this value is given, the StringFileInfo block must
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 * contain a PrivateBuild string.
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 *
 * VS_FF_SPECIALBUILD File *was* built by the original company using
 * standard release procedures but is a variation of the standard
 * file of the same version number. If this value is given, the
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 * StringFileInfo block must contain a SpecialBuild string.
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 */

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#ifdef PNG_USER_PRIVATEBUILD /* From pnglibconf.h */
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#  define PNG_LIBPNG_BUILD_TYPE \
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       (PNG_LIBPNG_BUILD_BASE_TYPE | PNG_LIBPNG_BUILD_PRIVATE)
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#else
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#  ifdef PNG_LIBPNG_SPECIALBUILD
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#    define PNG_LIBPNG_BUILD_TYPE \
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         (PNG_LIBPNG_BUILD_BASE_TYPE | PNG_LIBPNG_BUILD_SPECIAL)
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#  else
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#    define PNG_LIBPNG_BUILD_TYPE (PNG_LIBPNG_BUILD_BASE_TYPE)
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#  endif
#endif

#ifndef PNG_VERSION_INFO_ONLY

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/* Inhibit C++ name-mangling for libpng functions but not for system calls. */
#ifdef __cplusplus
extern "C" {
#endif /* __cplusplus */

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/* Version information for C files, stored in png.c.  This had better match
 * the version above.
 */
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#define png_libpng_ver png_get_header_ver(NULL)
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/* This file is arranged in several sections:
 *
 * 1. Any configuration options that can be specified by for the application
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 *    code when it is built.  (Build time configuration is in pnglibconf.h)
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 * 2. Type definitions (base types are defined in pngconf.h), structure
 *    definitions.
 * 3. Exported library functions.
 *
 * The library source code has additional files (principally pngpriv.h) that
 * allow configuration of the library.
 */
/* Section 1: run time configuration
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 * See pnglibconf.h for build time configuration
463 464 465
 *
 * Run time configuration allows the application to choose between
 * implementations of certain arithmetic APIs.  The default is set
466
 * at build time and recorded in pnglibconf.h, but it is safe to
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 * override these (and only these) settings.  Note that this won't
 * change what the library does, only application code, and the
 * settings can (and probably should) be made on a per-file basis
 * by setting the #defines before including png.h
 *
 * Use macros to read integers from PNG data or use the exported
 * functions?
 *   PNG_USE_READ_MACROS: use the macros (see below)  Note that
 *     the macros evaluate their argument multiple times.
 *   PNG_NO_USE_READ_MACROS: call the relevant library function.
 *
 * Use the alternative algorithm for compositing alpha samples that
 * does not use division?
 *   PNG_READ_COMPOSITE_NODIV_SUPPORTED: use the 'no division'
 *      algorithm.
 *   PNG_NO_READ_COMPOSITE_NODIV: use the 'division' algorithm.
 *
 * How to handle benign errors if PNG_ALLOW_BENIGN_ERRORS is
 * false?
 *   PNG_ALLOW_BENIGN_ERRORS: map calls to the benign error
 *      APIs to png_warning.
 * Otherwise the calls are mapped to png_error.
 */

/* Section 2: type definitions, including structures and compile time
 * constants.
 * See pngconf.h for base types that vary by machine/system
 */
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/* Three color definitions.  The order of the red, green, and blue, (and the
 * exact size) is not important, although the size of the fields need to
 * be png_byte or png_uint_16 (as defined below).
 */
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typedef struct png_color_struct
{
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   png_byte red;
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   png_byte green;
   png_byte blue;
} png_color;
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typedef png_color FAR * png_colorp;
typedef png_color FAR * FAR * png_colorpp;
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typedef struct png_color_16_struct
{
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   png_byte index;    /* used for palette files */
   png_uint_16 red;   /* for use in red green blue files */
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   png_uint_16 green;
   png_uint_16 blue;
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   png_uint_16 gray;  /* for use in grayscale files */
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} png_color_16;
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typedef png_color_16 FAR * png_color_16p;
typedef png_color_16 FAR * FAR * png_color_16pp;
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typedef struct png_color_8_struct
{
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   png_byte red;   /* for use in red green blue files */
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   png_byte green;
   png_byte blue;
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   png_byte gray;  /* for use in grayscale files */
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   png_byte alpha; /* for alpha channel files */
} png_color_8;
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typedef png_color_8 FAR * png_color_8p;
typedef png_color_8 FAR * FAR * png_color_8pp;
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/*
 * The following two structures are used for the in-core representation
 * of sPLT chunks.
 */
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typedef struct png_sPLT_entry_struct
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{
   png_uint_16 red;
   png_uint_16 green;
   png_uint_16 blue;
   png_uint_16 alpha;
   png_uint_16 frequency;
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} png_sPLT_entry;
typedef png_sPLT_entry FAR * png_sPLT_entryp;
typedef png_sPLT_entry FAR * FAR * png_sPLT_entrypp;
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/*  When the depth of the sPLT palette is 8 bits, the color and alpha samples
 *  occupy the LSB of their respective members, and the MSB of each member
 *  is zero-filled.  The frequency member always occupies the full 16 bits.
 */

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typedef struct png_sPLT_struct
551
{
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   png_charp name;           /* palette name */
   png_byte depth;           /* depth of palette samples */
   png_sPLT_entryp entries;  /* palette entries */
   png_int_32 nentries;      /* number of palette entries */
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} png_sPLT_t;
typedef png_sPLT_t FAR * png_sPLT_tp;
typedef png_sPLT_t FAR * FAR * png_sPLT_tpp;
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#ifdef PNG_TEXT_SUPPORTED
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/* png_text holds the contents of a text/ztxt/itxt chunk in a PNG file,
 * and whether that contents is compressed or not.  The "key" field
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 * points to a regular zero-terminated C string.  The "text", "lang", and
 * "lang_key" fields can be regular C strings, empty strings, or NULL pointers.
 * However, the * structure returned by png_get_text() will always contain
 * regular zero-terminated C strings (possibly empty), never NULL pointers,
 * so they can be safely used in printf() and other string-handling functions.
 */
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typedef struct png_text_struct
{
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   int  compression;       /* compression value:
                             -1: tEXt, none
                              0: zTXt, deflate
                              1: iTXt, none
                              2: iTXt, deflate  */
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   png_charp key;          /* keyword, 1-79 character description of "text" */
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   png_charp text;         /* comment, may be an empty string (ie "")
                              or a NULL pointer */
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   png_size_t text_length; /* length of the text string */
   png_size_t itxt_length; /* length of the itxt string */
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   png_charp lang;         /* language code, 0-79 characters
                              or a NULL pointer */
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   png_charp lang_key;     /* keyword translated UTF-8 string, 0 or more
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                              chars or a NULL pointer */
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} png_text;
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typedef png_text FAR * png_textp;
typedef png_text FAR * FAR * png_textpp;
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#endif
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/* Supported compression types for text in PNG files (tEXt, and zTXt).
 * The values of the PNG_TEXT_COMPRESSION_ defines should NOT be changed. */
#define PNG_TEXT_COMPRESSION_NONE_WR -3
#define PNG_TEXT_COMPRESSION_zTXt_WR -2
#define PNG_TEXT_COMPRESSION_NONE    -1
#define PNG_TEXT_COMPRESSION_zTXt     0
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#define PNG_ITXT_COMPRESSION_NONE     1
#define PNG_ITXT_COMPRESSION_zTXt     2
#define PNG_TEXT_COMPRESSION_LAST     3  /* Not a valid value */
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/* png_time is a way to hold the time in an machine independent way.
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 * Two conversions are provided, both from time_t and struct tm.  There
 * is no portable way to convert to either of these structures, as far
 * as I know.  If you know of a portable way, send it to me.  As a side
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 * note - PNG has always been Year 2000 compliant!
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 */
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typedef struct png_time_struct
{
   png_uint_16 year; /* full year, as in, 1995 */
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   png_byte month;   /* month of year, 1 - 12 */
   png_byte day;     /* day of month, 1 - 31 */
   png_byte hour;    /* hour of day, 0 - 23 */
   png_byte minute;  /* minute of hour, 0 - 59 */
   png_byte second;  /* second of minute, 0 - 60 (for leap seconds) */
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} png_time;
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typedef png_time FAR * png_timep;
typedef png_time FAR * FAR * png_timepp;

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#if defined(PNG_UNKNOWN_CHUNKS_SUPPORTED) || \
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    defined(PNG_HANDLE_AS_UNKNOWN_SUPPORTED)
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/* png_unknown_chunk is a structure to hold queued chunks for which there is
 * no specific support.  The idea is that we can use this to queue
 * up private chunks for output even though the library doesn't actually
 * know about their semantics.
 */
typedef struct png_unknown_chunk_t
{
    png_byte name[5];
    png_byte *data;
    png_size_t size;

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    /* libpng-using applications should NOT directly modify this byte. */
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    png_byte location; /* mode of operation at read time */
}
png_unknown_chunk;
typedef png_unknown_chunk FAR * png_unknown_chunkp;
typedef png_unknown_chunk FAR * FAR * png_unknown_chunkpp;
#endif

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typedef struct png_info_def png_info;
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typedef png_info FAR * png_infop;
typedef png_info FAR * FAR * png_infopp;
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/* Maximum positive integer used in PNG is (2^31)-1 */
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#define PNG_UINT_31_MAX ((png_uint_32)0x7fffffffL)
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#define PNG_UINT_32_MAX ((png_uint_32)(-1))
#define PNG_SIZE_MAX ((png_size_t)(-1))
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/* These describe the color_type field in png_info. */
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/* color type masks */
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#define PNG_COLOR_MASK_PALETTE    1
#define PNG_COLOR_MASK_COLOR      2
#define PNG_COLOR_MASK_ALPHA      4
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/* color types.  Note that not all combinations are legal */
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#define PNG_COLOR_TYPE_GRAY 0
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#define PNG_COLOR_TYPE_PALETTE  (PNG_COLOR_MASK_COLOR | PNG_COLOR_MASK_PALETTE)
#define PNG_COLOR_TYPE_RGB        (PNG_COLOR_MASK_COLOR)
#define PNG_COLOR_TYPE_RGB_ALPHA  (PNG_COLOR_MASK_COLOR | PNG_COLOR_MASK_ALPHA)
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#define PNG_COLOR_TYPE_GRAY_ALPHA (PNG_COLOR_MASK_ALPHA)
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/* aliases */
#define PNG_COLOR_TYPE_RGBA  PNG_COLOR_TYPE_RGB_ALPHA
#define PNG_COLOR_TYPE_GA  PNG_COLOR_TYPE_GRAY_ALPHA
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/* This is for compression type. PNG 1.0-1.2 only define the single type. */
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#define PNG_COMPRESSION_TYPE_BASE 0 /* Deflate method 8, 32K window */
#define PNG_COMPRESSION_TYPE_DEFAULT PNG_COMPRESSION_TYPE_BASE

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/* This is for filter type. PNG 1.0-1.2 only define the single type. */
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#define PNG_FILTER_TYPE_BASE      0 /* Single row per-byte filtering */
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#define PNG_INTRAPIXEL_DIFFERENCING 64 /* Used only in MNG datastreams */
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#define PNG_FILTER_TYPE_DEFAULT   PNG_FILTER_TYPE_BASE

/* These are for the interlacing type.  These values should NOT be changed. */
#define PNG_INTERLACE_NONE        0 /* Non-interlaced image */
#define PNG_INTERLACE_ADAM7       1 /* Adam7 interlacing */
#define PNG_INTERLACE_LAST        2 /* Not a valid value */

/* These are for the oFFs chunk.  These values should NOT be changed. */
#define PNG_OFFSET_PIXEL          0 /* Offset in pixels */
#define PNG_OFFSET_MICROMETER     1 /* Offset in micrometers (1/10^6 meter) */
#define PNG_OFFSET_LAST           2 /* Not a valid value */

/* These are for the pCAL chunk.  These values should NOT be changed. */
#define PNG_EQUATION_LINEAR       0 /* Linear transformation */
#define PNG_EQUATION_BASE_E       1 /* Exponential base e transform */
#define PNG_EQUATION_ARBITRARY    2 /* Arbitrary base exponential transform */
#define PNG_EQUATION_HYPERBOLIC   3 /* Hyperbolic sine transformation */
#define PNG_EQUATION_LAST         4 /* Not a valid value */

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/* These are for the sCAL chunk.  These values should NOT be changed. */
#define PNG_SCALE_UNKNOWN         0 /* unknown unit (image scale) */
#define PNG_SCALE_METER           1 /* meters per pixel */
#define PNG_SCALE_RADIAN          2 /* radians per pixel */
#define PNG_SCALE_LAST            3 /* Not a valid value */

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/* These are for the pHYs chunk.  These values should NOT be changed. */
#define PNG_RESOLUTION_UNKNOWN    0 /* pixels/unknown unit (aspect ratio) */
#define PNG_RESOLUTION_METER      1 /* pixels/meter */
#define PNG_RESOLUTION_LAST       2 /* Not a valid value */

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/* These are for the sRGB chunk.  These values should NOT be changed. */
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#define PNG_sRGB_INTENT_PERCEPTUAL 0
#define PNG_sRGB_INTENT_RELATIVE   1
#define PNG_sRGB_INTENT_SATURATION 2
#define PNG_sRGB_INTENT_ABSOLUTE   3
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#define PNG_sRGB_INTENT_LAST       4 /* Not a valid value */
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/* This is for text chunks */
#define PNG_KEYWORD_MAX_LENGTH     79
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711
/* Maximum number of entries in PLTE/sPLT/tRNS arrays */
712
#define PNG_MAX_PALETTE_LENGTH    256
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/* These determine if an ancillary chunk's data has been successfully read
 * from the PNG header, or if the application has filled in the corresponding
 * data in the info_struct to be written into the output file.  The values
 * of the PNG_INFO_<chunk> defines should NOT be changed.
 */
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#define PNG_INFO_gAMA 0x0001
#define PNG_INFO_sBIT 0x0002
#define PNG_INFO_cHRM 0x0004
#define PNG_INFO_PLTE 0x0008
#define PNG_INFO_tRNS 0x0010
#define PNG_INFO_bKGD 0x0020
#define PNG_INFO_hIST 0x0040
#define PNG_INFO_pHYs 0x0080
#define PNG_INFO_oFFs 0x0100
#define PNG_INFO_tIME 0x0200
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#define PNG_INFO_pCAL 0x0400
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#define PNG_INFO_sRGB 0x0800   /* GR-P, 0.96a */
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#define PNG_INFO_iCCP 0x1000   /* ESR, 1.0.6 */
#define PNG_INFO_sPLT 0x2000   /* ESR, 1.0.6 */
#define PNG_INFO_sCAL 0x4000   /* ESR, 1.0.6 */
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#define PNG_INFO_IDAT 0x8000L  /* ESR, 1.0.6 */
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/* This is used for the transformation routines, as some of them
 * change these values for the row.  It also should enable using
 * the routines for other purposes.
 */
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typedef struct png_row_info_struct
{
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   png_uint_32 width; /* width of row */
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   png_size_t rowbytes; /* number of bytes in row */
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   png_byte color_type; /* color type of row */
   png_byte bit_depth; /* bit depth of row */
   png_byte channels; /* number of channels (1, 2, 3, or 4) */
   png_byte pixel_depth; /* bits per pixel (depth * channels) */
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} png_row_info;

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typedef png_row_info FAR * png_row_infop;
typedef png_row_info FAR * FAR * png_row_infopp;
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/* These are the function types for the I/O functions and for the functions
 * that allow the user to override the default I/O functions with his or her
 * own.  The png_error_ptr type should match that of user-supplied warning
 * and error functions, while the png_rw_ptr type should match that of the
 * user read/write data functions.
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 */
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typedef struct png_struct_def png_struct;
typedef png_struct FAR * png_structp;

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typedef PNG_CALLBACK(void, *png_error_ptr, (png_structp, png_const_charp),);
typedef PNG_CALLBACK(void, *png_rw_ptr, (png_structp, png_bytep, png_size_t),);
typedef PNG_CALLBACK(void, *png_flush_ptr, (png_structp),);
typedef PNG_CALLBACK(void, *png_read_status_ptr, (png_structp, png_uint_32,
    int),);
typedef PNG_CALLBACK(void, *png_write_status_ptr, (png_structp, png_uint_32,
    int),);
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#ifdef PNG_PROGRESSIVE_READ_SUPPORTED
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typedef PNG_CALLBACK(void, *png_progressive_info_ptr,
    (png_structp, png_infop),);
typedef PNG_CALLBACK(void, *png_progressive_end_ptr, (png_structp, png_infop),);
typedef PNG_CALLBACK(void, *png_progressive_row_ptr, (png_structp, png_bytep,
    png_uint_32, int),);
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#endif
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#if defined(PNG_READ_USER_TRANSFORM_SUPPORTED) || \
779
    defined(PNG_WRITE_USER_TRANSFORM_SUPPORTED)
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typedef PNG_CALLBACK(void, *png_user_transform_ptr, (png_structp, png_row_infop,
    png_bytep),);
782
#endif
783

784
#ifdef PNG_USER_CHUNKS_SUPPORTED
785 786
typedef PNG_CALLBACK(int, *png_user_chunk_ptr, (png_structp,
    png_unknown_chunkp),);
787
#endif
788
#ifdef PNG_UNKNOWN_CHUNKS_SUPPORTED
789
typedef PNG_CALLBACK(void, *png_unknown_chunk_ptr, (png_structp),);
790
#endif
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#ifdef PNG_SETJMP_SUPPORTED
/* This must match the function definition in <setjmp.h>, and the
 * application must include this before png.h to obtain the definition
794
 * of jmp_buf.  The function is required to be PNG_NORETURN.
795
 */
796
typedef void (PNGCAPI *png_longjmp_ptr) PNGARG((jmp_buf, int)) PNG_NORETURN;
797
#endif
798 799

/* Transform masks for the high-level interface */
800 801
#define PNG_TRANSFORM_IDENTITY       0x0000    /* read and write */
#define PNG_TRANSFORM_STRIP_16       0x0001    /* read only */
802 803
#define PNG_TRANSFORM_STRIP_ALPHA    0x0002    /* read only */
#define PNG_TRANSFORM_PACKING        0x0004    /* read and write */
804 805
#define PNG_TRANSFORM_PACKSWAP       0x0008    /* read and write */
#define PNG_TRANSFORM_EXPAND         0x0010    /* read only */
806
#define PNG_TRANSFORM_INVERT_MONO    0x0020    /* read and write */
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#define PNG_TRANSFORM_SHIFT          0x0040    /* read and write */
#define PNG_TRANSFORM_BGR            0x0080    /* read and write */
#define PNG_TRANSFORM_SWAP_ALPHA     0x0100    /* read and write */
810
#define PNG_TRANSFORM_SWAP_ENDIAN    0x0200    /* read and write */
811
#define PNG_TRANSFORM_INVERT_ALPHA   0x0400    /* read and write */
812
#define PNG_TRANSFORM_STRIP_FILLER   0x0800    /* write only */
813
/* Added to libpng-1.2.34 */
814
#define PNG_TRANSFORM_STRIP_FILLER_BEFORE PNG_TRANSFORM_STRIP_FILLER
815 816 817
#define PNG_TRANSFORM_STRIP_FILLER_AFTER 0x1000 /* write only */
/* Added to libpng-1.4.0 */
#define PNG_TRANSFORM_GRAY_TO_RGB   0x2000      /* read only */
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819
/* Flags for MNG supported features */
820 821
#define PNG_FLAG_MNG_EMPTY_PLTE     0x01
#define PNG_FLAG_MNG_FILTER_64      0x04
822
#define PNG_ALL_MNG_FEATURES        0x05
823

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/* NOTE: prior to 1.5 these functions had no 'API' style declaration,
 * this allowed the zlib default functions to be used on Windows
 * platforms.  In 1.5 the zlib default malloc (which just calls malloc and
 * ignores the first argument) should be completely compatible with the
 * following.
 */
typedef PNG_CALLBACK(png_voidp, *png_malloc_ptr, (png_structp,
    png_alloc_size_t),);
typedef PNG_CALLBACK(void, *png_free_ptr, (png_structp, png_voidp),);
833

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/* This triggers a compiler error in png.c, if png.c and png.h
 * do not agree upon the version number.
836
 */
837
typedef png_structp version_1_5_0beta24;
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typedef png_struct FAR * FAR * png_structpp;
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/* Section 3: exported functions
 * Here are the function definitions most commonly used.  This is not
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 * the place to find out how to use libpng.  See libpng.txt for the
 * full explanation, see example.c for the summary.  This just provides
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 * a simple one line description of the use of each function.
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 */
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/* Returns the version number of the library */
849
extern PNG_EXPORT(png_uint_32,png_access_version_number,(void),,1);
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/* Tell lib we have already handled the first <num_bytes> magic bytes.
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 * Handling more than 8 bytes from the beginning of the file is an error.
 */
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extern PNG_EXPORT(void,png_set_sig_bytes,(png_structp png_ptr,
    int num_bytes),,2);
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/* Check sig[start] through sig[start + num_to_check - 1] to see if it's a
 * PNG file.  Returns zero if the supplied bytes match the 8-byte PNG
 * signature, and non-zero otherwise.  Having num_to_check == 0 or
 * start > 7 will always fail (ie return non-zero).
 */
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extern PNG_EXPORT(int,png_sig_cmp,(png_bytep sig, png_size_t start,
    png_size_t num_to_check),,3);
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/* Simple signature checking function.  This is the same as calling
 * png_check_sig(sig, n) := !png_sig_cmp(sig, 0, n).
 */
#define png_check_sig(sig,n) !png_sig_cmp((sig), 0, (n))

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/* Allocate and initialize png_ptr struct for reading, and any other memory. */
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extern PNG_EXPORT(png_structp,png_create_read_struct,
    (png_const_charp user_png_ver, png_voidp error_ptr,
    png_error_ptr error_fn, png_error_ptr warn_fn),PNG_ALLOCATED,4);
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/* Allocate and initialize png_ptr struct for writing, and any other memory */
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extern PNG_EXPORT(png_structp,png_create_write_struct,
    (png_const_charp user_png_ver, png_voidp error_ptr,
    png_error_ptr error_fn, png_error_ptr warn_fn),PNG_ALLOCATED,5);
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extern PNG_EXPORT(png_size_t,png_get_compression_buffer_size,(png_structp
    png_ptr),,6);
882

883 884
extern PNG_EXPORT(void,png_set_compression_buffer_size,(png_structp png_ptr,
    png_size_t size),,7);
885

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/* Moved from pngconf.h in 1.4.0 and modified to ensure setjmp/longjmp
 * match up.
 */
#ifdef PNG_SETJMP_SUPPORTED
/* This function returns the jmp_buf built in to *png_ptr.  It must be
 * supplied with an appropriate 'longjmp' function to use on that jmp_buf
 * unless the default error function is overridden in which case NULL is
 * acceptable.  The size of the jmp_buf is checked against the actual size
 * allocated by the library - the call will return NULL on a mismatch
 * indicating an ABI mismatch.
 */
897 898
extern PNG_EXPORT(jmp_buf*, png_set_longjmp_fn, (png_structp png_ptr,
    png_longjmp_ptr longjmp_fn, size_t jmp_buf_size),,8);
899
#  define png_jmpbuf(png_ptr) \
900
      (*png_set_longjmp_fn((png_ptr), longjmp, sizeof (jmp_buf)))
901 902
#else
#  define png_jmpbuf(png_ptr) \
903
      (LIBPNG_WAS_COMPILED_WITH__PNG_NO_SETJMP)
904
#endif
905 906 907 908 909
/* This function should be used by libpng applications in place of
 * longjmp(png_ptr->jmpbuf, val).  If longjmp_fn() has been set, it
 * will use it; otherwise it will call PNG_ABORT().  This function was
 * added in libpng-1.5.0.
 */
910 911
extern PNG_EXPORT(void, png_longjmp, (png_structp png_ptr, int val),
    PNG_NORETURN,9);
912

913
#ifdef PNG_READ_SUPPORTED
914
/* Reset the compression stream */
915
extern PNG_EXPORT(int,png_reset_zstream,(png_structp png_ptr),,10);
916
#endif
917

918
/* New functions added in libpng-1.0.2 (not enabled by default until 1.2.0) */
919
#ifdef PNG_USER_MEM_SUPPORTED
920 921
extern PNG_EXPORT(png_structp,png_create_read_struct_2,
    (png_const_charp user_png_ver, png_voidp error_ptr,
922
    png_error_ptr error_fn, png_error_ptr warn_fn, png_voidp mem_ptr,
923 924 925
    png_malloc_ptr malloc_fn, png_free_ptr free_fn),PNG_ALLOCATED,11);
extern PNG_EXPORT(png_structp,png_create_write_struct_2,
    (png_const_charp user_png_ver, png_voidp error_ptr,
926
    png_error_ptr error_fn, png_error_ptr warn_fn, png_voidp mem_ptr,
927
    png_malloc_ptr malloc_fn, png_free_ptr free_fn),PNG_ALLOCATED,12);
928 929
#endif

930
/* Write the PNG file signature. */
931
extern PNG_EXPORT(void,png_write_sig,(png_structp png_ptr),,13);
932

933
/* Write a PNG chunk - size, type, (optional) data, CRC. */
934 935
extern PNG_EXPORT(void,png_write_chunk,(png_structp png_ptr,
    png_bytep chunk_name, png_bytep data, png_size_t length),,14);
936 937

/* Write the start of a PNG chunk - length and chunk name. */
938 939
extern PNG_EXPORT(void,png_write_chunk_start,(png_structp png_ptr,
    png_bytep chunk_name, png_uint_32 length),,15);
940 941

/* Write the data of a PNG chunk started with png_write_chunk_start(). */
942 943
extern PNG_EXPORT(void,png_write_chunk_data,(png_structp png_ptr,
    png_bytep data, png_size_t length),,16);
944 945

/* Finish a chunk started with png_write_chunk_start() (includes CRC). */
946
extern PNG_EXPORT(void,png_write_chunk_end,(png_structp png_ptr),,17);
947

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948
/* Allocate and initialize the info structure */
949 950
extern PNG_EXPORT(png_infop,png_create_info_struct,(png_structp png_ptr),
    PNG_ALLOCATED,18);
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952 953
extern PNG_EXPORT(void,png_info_init_3,(png_infopp info_ptr,
    png_size_t png_info_struct_size),,19);
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954

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955
/* Writes all the PNG information before the image. */
956 957 958 959
extern PNG_EXPORT(void,png_write_info_before_PLTE,(png_structp png_ptr,
    png_infop info_ptr),,20);
extern PNG_EXPORT(void,png_write_info,(png_structp png_ptr,
    png_infop info_ptr),,21);
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960

961
#ifdef PNG_SEQUENTIAL_READ_SUPPORTED
962
/* Read the information before the actual image data. */
963 964
extern PNG_EXPORT(void,png_read_info,(png_structp png_ptr,
    png_infop info_ptr),,22);
965
#endif
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966

967
#ifdef PNG_TIME_RFC1123_SUPPORTED
968 969
extern PNG_EXPORT(png_charp,png_convert_to_rfc1123,(png_structp png_ptr,
    png_timep ptime),,23);
970
#endif
971

972
#ifdef PNG_CONVERT_tIME_SUPPORTED
973
/* Convert from a struct tm to png_time */
974 975
extern PNG_EXPORT(void,png_convert_from_struct_tm,(png_timep ptime,
    struct tm FAR * ttime),,24);
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976

977
/* Convert from time_t to png_time.  Uses gmtime() */
978 979
extern PNG_EXPORT(void,png_convert_from_time_t,(png_timep ptime,
    time_t ttime),,25);
980
#endif /* PNG_CONVERT_tIME_SUPPORTED */
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981

982
#ifdef PNG_READ_EXPAND_SUPPORTED
983
/* Expand data to 24-bit RGB, or 8-bit grayscale, with alpha if available. */
984 985 986 987 988
extern PNG_EXPORT(void,png_set_expand,(png_structp png_ptr),,26);
extern PNG_EXPORT(void,png_set_expand_gray_1_2_4_to_8,(png_structp png_ptr),,
    27);
extern PNG_EXPORT(void,png_set_palette_to_rgb,(png_structp png_ptr),,28);
extern PNG_EXPORT(void,png_set_tRNS_to_alpha,(png_structp png_ptr),,29);
989
#endif
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991
#if defined(PNG_READ_BGR_SUPPORTED) || defined(PNG_WRITE_BGR_SUPPORTED)
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992
/* Use blue, green, red order for pixels. */
993
extern PNG_EXPORT(void,png_set_bgr,(png_structp png_ptr),,30);
994
#endif
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996
#ifdef PNG_READ_GRAY_TO_RGB_SUPPORTED
997
/* Expand the grayscale to 24-bit RGB if necessary. */
998
extern PNG_EXPORT(void,png_set_gray_to_rgb,(png_structp png_ptr),,31);
999
#endif
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1000

1001
#ifdef PNG_READ_RGB_TO_GRAY_SUPPORTED
1002
/* Reduce RGB to grayscale. */
1003
#  ifdef PNG_FLOATING_POINT_SUPPORTED
1004 1005
extern PNG_EXPORT(void,png_set_rgb_to_gray,(png_structp png_ptr,
    int error_action, double red, double green ),,32);
1006
#  endif
1007 1008 1009 1010
extern PNG_EXPORT(void,png_set_rgb_to_gray_fixed,(png_structp png_ptr,
    int error_action, png_fixed_point red, png_fixed_point green),,33);
extern PNG_EXPORT(png_byte,png_get_rgb_to_gray_status,(png_structp png_ptr),,
    34);
1011
#endif
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1013 1014
extern PNG_EXPORT(void,png_build_grayscale_palette,(int bit_depth,
    png_colorp palette),,35);
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1015

1016
#ifdef PNG_READ_STRIP_ALPHA_SUPPORTED
1017
extern PNG_EXPORT(void,png_set_strip_alpha,(png_structp png_ptr),,36);
1018
#endif
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1019

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1020 1021
#if defined(PNG_READ_SWAP_ALPHA_SUPPORTED) || \
    defined(PNG_WRITE_SWAP_ALPHA_SUPPORTED)
1022
extern PNG_EXPORT(void,png_set_swap_alpha,(png_structp png_ptr),,37);
1023
#endif
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1024

1025 1026
#if defined(PNG_READ_INVERT_ALPHA_SUPPORTED) || \
    defined(PNG_WRITE_INVERT_ALPHA_SUPPORTED)
1027
extern PNG_EXPORT(void,png_set_invert_alpha,(png_structp png_ptr),,38);
1028
#endif
1029

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1030
#if defined(PNG_READ_FILLER_SUPPORTED) || defined(PNG_WRITE_FILLER_SUPPORTED)
1031
/* Add a filler byte to 8-bit Gray or 24-bit RGB images. */
1032 1033
extern PNG_EXPORT(void,png_set_filler,(png_structp png_ptr,
    png_uint_32 filler, int flags),,39);
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1034
/* The values of the PNG_FILLER_ defines should NOT be changed */
1035 1036
#  define PNG_FILLER_BEFORE 0
#  define PNG_FILLER_AFTER 1
1037
/* Add an alpha byte to 8-bit Gray or 24-bit RGB images. */
1038 1039
extern PNG_EXPORT(void,png_set_add_alpha,(png_structp png_ptr,
    png_uint_32 filler, int flags),,40);
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1040
#endif /* PNG_READ_FILLER_SUPPORTED || PNG_WRITE_FILLER_SUPPORTED */
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1041

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1042
#if defined(PNG_READ_SWAP_SUPPORTED) || defined(PNG_WRITE_SWAP_SUPPORTED)
1043
/* Swap bytes in 16-bit depth files. */
1044
extern PNG_EXPORT(void,png_set_swap,(png_structp png_ptr),,41);
1045
#endif
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1046

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1047
#if defined(PNG_READ_PACK_SUPPORTED) || defined(PNG_WRITE_PACK_SUPPORTED)
1048
/* Use 1 byte per pixel in 1, 2, or 4-bit depth files. */
1049
extern PNG_EXPORT(void,png_set_packing,(png_structp png_ptr),,42);
1050
#endif
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1051

1052 1053
#if defined(PNG_READ_PACKSWAP_SUPPORTED) || \
    defined(PNG_WRITE_PACKSWAP_SUPPORTED)
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1054
/* Swap packing order of pixels in bytes. */
1055
extern PNG_EXPORT(void,png_set_packswap,(png_structp png_ptr),,43);
1056
#endif
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1057

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1058
#if defined(PNG_READ_SHIFT_SUPPORTED) || defined(PNG_WRITE_SHIFT_SUPPORTED)
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1059
/* Converts files to legal bit depths. */
1060 1061
extern PNG_EXPORT(void,png_set_shift,(png_structp png_ptr,
    png_color_8p true_bits),,44);
1062
#endif
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1063

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1064 1065
#if defined(PNG_READ_INTERLACING_SUPPORTED) || \
    defined(PNG_WRITE_INTERLACING_SUPPORTED)
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1066
/* Have the code handle the interlacing.  Returns the number of passes. */
1067
extern PNG_EXPORT(int,png_set_interlace_handling,(png_structp png_ptr),,45);
1068
#endif
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1069

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1070
#if defined(PNG_READ_INVERT_SUPPORTED) || defined(PNG_WRITE_INVERT_SUPPORTED)
1071
/* Invert monochrome files */
1072
extern PNG_EXPORT(void,png_set_invert_mono,(png_structp png_ptr),,46);
1073
#endif
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1074

1075
#ifdef PNG_READ_BACKGROUND_SUPPORTED
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1076
/* Handle alpha and tRNS by replacing with a background color. */
1077
#  ifdef PNG_FLOATING_POINT_SUPPORTED
1078
extern PNG_EXPORT(void,png_set_background,(png_structp png_ptr,
1079
    png_color_16p background_color, int background_gamma_code,
1080
    int need_expand, double background_gamma),,47);
1081 1082 1083 1084 1085
#  endif
#  define PNG_BACKGROUND_GAMMA_UNKNOWN 0
#  define PNG_BACKGROUND_GAMMA_SCREEN  1
#  define PNG_BACKGROUND_GAMMA_FILE    2
#  define PNG_BACKGROUND_GAMMA_UNIQUE  3
1086
#endif
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1087

1088
#ifdef PNG_READ_16_TO_8_SUPPORTED
1089
/* Strip the second byte of information from a 16-bit depth file. */
1090
extern PNG_EXPORT(void,png_set_strip_16,(png_structp png_ptr),,48);
1091
#endif
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1092

1093 1094
#ifdef PNG_READ_QUANTIZE_SUPPORTED
/* Turn on quantizing, and reduce the palette to the number of colors
1095 1096
 * available.
 */
1097
extern PNG_EXPORT(void,png_set_quantize,(png_structp png_ptr,
1098
    png_colorp palette, int num_palette, int maximum_colors,
1099
    png_uint_16p histogram, int full_quantize),,49);
1100
#endif
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1101

1102
#ifdef PNG_READ_GAMMA_SUPPORTED
1103
/* Handle gamma correction. Screen_gamma=(display_exponent) */
1104
#  ifdef PNG_FLOATING_POINT_SUPPORTED
1105 1106
extern PNG_EXPORT(void,png_set_gamma,(png_structp png_ptr, 
    double screen_gamma, double default_file_gamma),,50);
1107
#  endif
1108
#endif
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1109

1110

1111
#ifdef PNG_WRITE_FLUSH_SUPPORTED
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1112
/* Set how many lines between output flushes - 0 for no flushing */
1113
extern PNG_EXPORT(void,png_set_flush,(png_structp png_ptr, int nrows),,51);
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1114
/* Flush the current PNG output buffer */
1115
extern PNG_EXPORT(void,png_write_flush,(png_structp png_ptr),,52);
1116
#endif
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1117

1118
/* Optional update palette with requested transformations */
1119
extern PNG_EXPORT(void,png_start_read_image,(png_structp png_ptr),,53);
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1120

1121
/* Optional call to update the users info structure */
1122 1123
extern PNG_EXPORT(void,png_read_update_info,(png_structp png_ptr,
    png_infop info_ptr),,54);
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1124

1125
#ifdef PNG_SEQUENTIAL_READ_SUPPORTED
1126
/* Read one or more rows of image data. */
1127 1128
extern PNG_EXPORT(void,png_read_rows,(png_structp png_ptr, png_bytepp row,
    png_bytepp display_row, png_uint_32 num_rows),,55);
1129
#endif
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1130

1131
#ifdef PNG_SEQUENTIAL_READ_SUPPORTED
1132
/* Read a row of data. */
1133 1134
extern PNG_EXPORT(void,png_read_row,(png_structp png_ptr, png_bytep row,
    png_bytep display_row),,56);
1135
#endif
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1136

1137
#ifdef PNG_SEQUENTIAL_READ_SUPPORTED
1138
/* Read the whole image into memory at once. */
1139 1140
extern PNG_EXPORT(void,png_read_image,(png_structp png_ptr,
    png_bytepp image),,57);
1141
#endif
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1142

1143
/* Write a row of image data */
1144
extern PNG_EXPORT(void,png_write_row,(png_structp png_ptr, png_bytep row),,58);
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1145

1146
/* Write a few rows of image data */
1147 1148
extern PNG_EXPORT(void,png_write_rows,(png_structp png_ptr,
    png_bytepp row, png_uint_32 num_rows),,59);
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1149

1150
/* Write the image data */
1151 1152
extern PNG_EXPORT(void,png_write_image,(png_structp png_ptr,
    png_bytepp image),,60);
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1153

1154
/* Write the end of the PNG file. */
1155 1156
extern PNG_EXPORT(void,png_write_end,(png_structp png_ptr,
    png_infop info_ptr),,61);
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1157

1158
#ifdef PNG_SEQUENTIAL_READ_SUPPORTED
1159
/* Read the end of the PNG file. */
1160 1161
extern PNG_EXPORT(void,png_read_end,(png_structp png_ptr,
    png_infop info_ptr),,62);
1162
#endif
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1163

1164
/* Free any memory associated with the png_info_struct */
1165 1166
extern PNG_EXPORT(void,png_destroy_info_struct,(png_structp png_ptr,
    png_infopp info_ptr_ptr),,63);
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1167

1168
/* Free any memory associated with the png_struct and the png_info_structs */
1169 1170
extern PNG_EXPORT(void,png_destroy_read_struct,(png_structpp png_ptr_ptr,
    png_infopp info_ptr_ptr, png_infopp end_info_ptr_ptr),,64);
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1171

1172
/* Free any memory associated with the png_struct and the png_info_structs */
1173 1174
extern PNG_EXPORT(void,png_destroy_write_struct,(png_structpp png_ptr_ptr,
    png_infopp info_ptr_ptr),,65);
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1175

1176
/* Set the libpng method of handling chunk CRC errors */
1177 1178
extern PNG_EXPORT(void,png_set_crc_action,(png_structp png_ptr,
    int crit_action, int ancil_action),,66);
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1179 1180

/* Values for png_set_crc_action() to say how to handle CRC errors in
A
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1181 1182 1183 1184 1185 1186 1187
 * ancillary and critical chunks, and whether to use the data contained
 * therein.  Note that it is impossible to "discard" data in a critical
 * chunk.  For versions prior to 0.90, the action was always error/quit,
 * whereas in version 0.90 and later, the action for CRC errors in ancillary
 * chunks is warn/discard.  These values should NOT be changed.
 *
 *      value                       action:critical     action:ancillary
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 */
#define PNG_CRC_DEFAULT       0  /* error/quit          warn/discard data */
#define PNG_CRC_ERROR_QUIT    1  /* error/quit          error/quit        */
#define PNG_CRC_WARN_DISCARD  2  /* (INVALID)           warn/discard data */
#define PNG_CRC_WARN_USE      3  /* warn/use data       warn/use data     */
#define PNG_CRC_QUIET_USE     4  /* quiet/use data      quiet/use data    */
#define PNG_CRC_NO_CHANGE     5  /* use current value   use current value */

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1196 1197 1198 1199 1200
/* These functions give the user control over the scan-line filtering in
 * libpng and the compression methods used by zlib.  These functions are
 * mainly useful for testing, as the defaults should work with most users.
 * Those users who are tight on memory or want faster performance at the
 * expense of compression can modify them.  See the compression library
1201 1202
 * header file (zlib.h) for an explination of the compression functions.
 */
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1203

1204
/* Set the filtering method(s) used by libpng.  Currently, the only valid
1205 1206
 * value for "method" is 0.
 */
1207 1208
extern PNG_EXPORT(void,png_set_filter,(png_structp png_ptr, int method,
    int filters),,67);
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1210
/* Flags for png_set_filter() to say which filters to use.  The flags
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1211 1212 1213
 * are chosen so that they don't conflict with real filter types
 * below, in case they are supplied instead of the #defined constants.
 * These values should NOT be changed.
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 */
#define PNG_NO_FILTERS     0x00
#define PNG_FILTER_NONE    0x08
#define PNG_FILTER_SUB     0x10
#define PNG_FILTER_UP      0x20
#define PNG_FILTER_AVG     0x40
#define PNG_FILTER_PAETH   0x80
#define PNG_ALL_FILTERS (PNG_FILTER_NONE | PNG_FILTER_SUB | PNG_FILTER_UP | \
                         PNG_FILTER_AVG | PNG_FILTER_PAETH)

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/* Filter values (not flags) - used in pngwrite.c, pngwutil.c for now.
 * These defines should NOT be changed.
 */
#define PNG_FILTER_VALUE_NONE  0
#define PNG_FILTER_VALUE_SUB   1
#define PNG_FILTER_VALUE_UP    2
#define PNG_FILTER_VALUE_AVG   3
#define PNG_FILTER_VALUE_PAETH 4
#define PNG_FILTER_VALUE_LAST  5

1234
#ifdef PNG_WRITE_WEIGHTED_FILTER_SUPPORTED /* EXPERIMENTAL */
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/* The "heuristic_method" is given by one of the PNG_FILTER_HEURISTIC_
 * defines, either the default (minimum-sum-of-absolute-differences), or
 * the experimental method (weighted-minimum-sum-of-absolute-differences).
 *
 * Weights are factors >= 1.0, indicating how important it is to keep the
 * filter type consistent between rows.  Larger numbers mean the current
 * filter is that many times as likely to be the same as the "num_weights"
 * previous filters.  This is cumulative for each previous row with a weight.
 * There needs to be "num_weights" values in "filter_weights", or it can be
 * NULL if the weights aren't being specified.  Weights have no influence on
 * the selection of the first row filter.  Well chosen weights can (in theory)
 * improve the compression for a given image.
 *
 * Costs are factors >= 1.0 indicating the relative decoding costs of a
 * filter type.  Higher costs indicate more decoding expense, and are
 * therefore less likely to be selected over a filter with lower computational
 * costs.  There needs to be a value in "filter_costs" for each valid filter
 * type (given by PNG_FILTER_VALUE_LAST), or it can be NULL if you aren't
 * setting the costs.  Costs try to improve the speed of decompression without
 * unduly increasing the compressed image size.
 *
 * A negative weight or cost indicates the default value is to be used, and
 * values in the range [0.0, 1.0) indicate the value is to remain unchanged.
 * The default values for both weights and costs are currently 1.0, but may
 * change if good general weighting/cost heuristics can be found.  If both
 * the weights and costs are set to 1.0, this degenerates the WEIGHTED method
 * to the UNWEIGHTED method, but with added encoding time/computation.
 */
1263
#  ifdef PNG_FLOATING_POINT_SUPPORTED
1264
extern PNG_EXPORT(void,png_set_filter_heuristics,(png_structp png_ptr,
1265
    int heuristic_method, int num_weights, png_doublep filter_weights,
1266
    png_doublep filter_costs),,68);
1267
#  endif
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#endif /*  PNG_WRITE_WEIGHTED_FILTER_SUPPORTED */

/* Heuristic used for row filter selection.  These defines should NOT be
 * changed.
 */
#define PNG_FILTER_HEURISTIC_DEFAULT    0  /* Currently "UNWEIGHTED" */
#define PNG_FILTER_HEURISTIC_UNWEIGHTED 1  /* Used by libpng < 0.95 */
#define PNG_FILTER_HEURISTIC_WEIGHTED   2  /* Experimental feature */
#define PNG_FILTER_HEURISTIC_LAST       3  /* Not a valid value */

/* Set the library compression level.  Currently, valid values range from
 * 0 - 9, corresponding directly to the zlib compression levels 0 - 9
 * (0 - no compression, 9 - "maximal" compression).  Note that tests have
 * shown that zlib compression levels 3-6 usually perform as well as level 9
 * for PNG images, and do considerably fewer caclulations.  In the future,
 * these values may not correspond directly to the zlib compression levels.
 */
1285 1286
extern PNG_EXPORT(void,png_set_compression_level,(png_structp png_ptr,
    int level),,69);
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1288 1289
extern PNG_EXPORT(void,png_set_compression_mem_level,(png_structp png_ptr,
    int mem_level),,70);
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1290

1291 1292
extern PNG_EXPORT(void,png_set_compression_strategy,(png_structp png_ptr,
    int strategy),,71);
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1293

1294 1295
extern PNG_EXPORT(void,png_set_compression_window_bits,(png_structp png_ptr,
    int window_bits),,72);
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1296

1297 1298
extern PNG_EXPORT(void,png_set_compression_method,(png_structp png_ptr,
    int method),,73);
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1299

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1300
/* These next functions are called for input/output, memory, and error
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1301 1302 1303 1304 1305 1306 1307
 * handling.  They are in the file pngrio.c, pngwio.c, and pngerror.c,
 * and call standard C I/O routines such as fread(), fwrite(), and
 * fprintf().  These functions can be made to use other I/O routines
 * at run time for those applications that need to handle I/O in a
 * different manner by calling png_set_???_fn().  See libpng.txt for
 * more information.
 */
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1308

1309
#ifdef PNG_STDIO_SUPPORTED
A
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1310
/* Initialize the input/output for the PNG file to the default functions. */
1311
extern PNG_EXPORT(void,png_init_io,(png_structp png_ptr, png_FILE_p fp),,74);
1312
#endif
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1313

A
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1314
/* Replace the (error and abort), and warning functions with user
A
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1315 1316 1317 1318 1319 1320
 * supplied functions.  If no messages are to be printed you must still
 * write and use replacement functions. The replacement error_fn should
 * still do a longjmp to the last setjmp location if you are using this
 * method of error handling.  If error_fn or warning_fn is NULL, the
 * default function will be used.
 */
1321

1322 1323 1324
extern PNG_EXPORT(void,png_set_error_fn,(png_structp png_ptr,
    png_voidp error_ptr, png_error_ptr error_fn,
    png_error_ptr warning_fn),,75);
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1325

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1326
/* Return the user pointer associated with the error functions */
1327
extern PNG_EXPORT(png_voidp,png_get_error_ptr,(png_structp png_ptr),,76);
G
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1328 1329

/* Replace the default data output functions with a user supplied one(s).
A
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1330 1331 1332
 * If buffered output is not used, then output_flush_fn can be set to NULL.
 * If PNG_WRITE_FLUSH_SUPPORTED is not defined at libpng compile time
 * output_flush_fn will be ignored (and thus can be NULL).
1333 1334 1335 1336 1337
 * It is probably a mistake to use NULL for output_flush_fn if
 * write_data_fn is not also NULL unless you have built libpng with
 * PNG_WRITE_FLUSH_SUPPORTED undefined, because in this case libpng's
 * default flush function, which uses the standard *FILE structure, will
 * be used.
A
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1338
 */
1339 1340 1341
extern PNG_EXPORT(void,png_set_write_fn,(png_structp png_ptr,
    png_voidp io_ptr, png_rw_ptr write_data_fn,
    png_flush_ptr output_flush_fn),,77);
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1342 1343

/* Replace the default data input function with a user supplied one. */
1344 1345
extern PNG_EXPORT(void,png_set_read_fn,(png_structp png_ptr,
    png_voidp io_ptr, png_rw_ptr read_data_fn),,78);
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1346 1347

/* Return the user pointer associated with the I/O functions */
1348
extern PNG_EXPORT(png_voidp,png_get_io_ptr,(png_structp png_ptr),,79);
G
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1349

1350 1351
extern PNG_EXPORT(void,png_set_read_status_fn,(png_structp png_ptr,
    png_read_status_ptr read_row_fn),,80);
1352

1353 1354
extern PNG_EXPORT(void,png_set_write_status_fn,(png_structp png_ptr,
    png_write_status_ptr write_row_fn),,81);
1355

1356 1357
#ifdef PNG_USER_MEM_SUPPORTED
/* Replace the default memory allocation functions with user supplied one(s). */
1358 1359
extern PNG_EXPORT(void,png_set_mem_fn,(png_structp png_ptr,
    png_voidp mem_ptr, png_malloc_ptr malloc_fn, png_free_ptr free_fn),,82);
1360
/* Return the user pointer associated with the memory functions */
1361
extern PNG_EXPORT(png_voidp,png_get_mem_ptr,(png_structp png_ptr),,83);
1362
#endif
1363

1364
#ifdef PNG_READ_USER_TRANSFORM_SUPPORTED
1365 1366
extern PNG_EXPORT(void,png_set_read_user_transform_fn,(png_structp png_ptr,
    png_user_transform_ptr read_user_transform_fn),,84);
1367 1368
#endif

1369
#ifdef PNG_WRITE_USER_TRANSFORM_SUPPORTED
1370 1371
extern PNG_EXPORT(void,png_set_write_user_transform_fn,(png_structp png_ptr,
    png_user_transform_ptr write_user_transform_fn),,85);
1372 1373
#endif

1374
#if defined(PNG_READ_USER_TRANSFORM_SUPPORTED) || \
1375
    defined(PNG_WRITE_USER_TRANSFORM_SUPPORTED)
1376 1377 1378
extern PNG_EXPORT(void,png_set_user_transform_info,(png_structp png_ptr,
    png_voidp user_transform_ptr, int user_transform_depth,
    int user_transform_channels),,86);
1379
/* Return the user pointer associated with the user transform functions */
1380 1381
extern PNG_EXPORT(png_voidp,png_get_user_transform_ptr,
    (png_structp png_ptr),,87);
1382 1383
#endif

1384
#ifdef PNG_USER_CHUNKS_SUPPORTED
1385 1386 1387
extern PNG_EXPORT(void,png_set_read_user_chunk_fn,(png_structp png_ptr,
    png_voidp user_chunk_ptr, png_user_chunk_ptr read_user_chunk_fn),,88);
extern PNG_EXPORT(png_voidp,png_get_user_chunk_ptr,(png_structp png_ptr),,89);
1388 1389
#endif

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1390
#ifdef PNG_PROGRESSIVE_READ_SUPPORTED
A
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1391 1392 1393
/* Sets the function callbacks for the push reader, and a pointer to a
 * user-defined structure available to the callback functions.
 */
1394 1395 1396
extern PNG_EXPORT(void,png_set_progressive_read_fn,(png_structp png_ptr,
    png_voidp progressive_ptr, png_progressive_info_ptr info_fn,
    png_progressive_row_ptr row_fn, png_progressive_end_ptr end_fn),,90);
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1397

1398
/* Returns the user pointer associated with the push read functions */
1399
extern PNG_EXPORT(png_voidp,png_get_progressive_ptr,(png_structp png_ptr),,91);
A
Andreas Dilger 已提交
1400

1401
/* Function to be called when data becomes available */
1402 1403
extern PNG_EXPORT(void,png_process_data,(png_structp png_ptr,
    png_infop info_ptr, png_bytep buffer, png_size_t buffer_size),,92);
A
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1404

1405
/* Function that combines rows.  Not very much different than the
A
Andreas Dilger 已提交
1406 1407
 * png_combine_row() call.  Is this even used?????
 */
1408 1409
extern PNG_EXPORT(void,png_progressive_combine_row,(png_structp png_ptr,
    png_bytep old_row, png_bytep new_row),,93);
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1410
#endif /* PNG_PROGRESSIVE_READ_SUPPORTED */
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1411

1412 1413
extern PNG_EXPORT(png_voidp,png_malloc,(png_structp png_ptr,
    png_alloc_size_t size),PNG_ALLOCATED,94);
1414
/* Added at libpng version 1.4.0 */
1415 1416
extern PNG_EXPORT(png_voidp,png_calloc,(png_structp png_ptr,
    png_alloc_size_t size),PNG_ALLOCATED,95);
G
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1417

1418
/* Added at libpng version 1.2.4 */
1419 1420
extern PNG_EXPORT(png_voidp,png_malloc_warn,(png_structp png_ptr,
    png_alloc_size_t size),PNG_ALLOCATED,96);
1421

1422
/* Frees a pointer allocated by png_malloc() */
1423
extern PNG_EXPORT(void,png_free,(png_structp png_ptr, png_voidp ptr),,97);
A
Andreas Dilger 已提交
1424

1425
/* Free data that was allocated internally */
1426 1427
extern PNG_EXPORT(void,png_free_data,(png_structp png_ptr, png_infop info_ptr,
    png_uint_32 free_me, int num),,98);
1428 1429
/* Reassign responsibility for freeing existing data, whether allocated
 * by libpng or by the application */
1430 1431
extern PNG_EXPORT(void,png_data_freer,(png_structp png_ptr, png_infop info_ptr,
    int freer, png_uint_32 mask),,99);
1432
/* Assignments for png_data_freer */
1433 1434 1435 1436
#define PNG_DESTROY_WILL_FREE_DATA 1
#define PNG_SET_WILL_FREE_DATA 1
#define PNG_USER_WILL_FREE_DATA 2
/* Flags for png_ptr->free_me and info_ptr->free_me */
1437 1438 1439 1440
#define PNG_FREE_HIST 0x0008
#define PNG_FREE_ICCP 0x0010
#define PNG_FREE_SPLT 0x0020
#define PNG_FREE_ROWS 0x0040
1441 1442
#define PNG_FREE_PCAL 0x0080
#define PNG_FREE_SCAL 0x0100
1443 1444
#define PNG_FREE_UNKN 0x0200
#define PNG_FREE_LIST 0x0400
1445 1446 1447
#define PNG_FREE_PLTE 0x1000
#define PNG_FREE_TRNS 0x2000
#define PNG_FREE_TEXT 0x4000
1448
#define PNG_FREE_ALL  0x7fff
1449
#define PNG_FREE_MUL  0x4220 /* PNG_FREE_SPLT|PNG_FREE_TEXT|PNG_FREE_UNKN */
1450

1451
#ifdef PNG_USER_MEM_SUPPORTED
1452 1453 1454 1455
extern PNG_EXPORT(png_voidp,png_malloc_default,(png_structp png_ptr,
    png_alloc_size_t size),PNG_ALLOCATED,100);
extern PNG_EXPORT(void,png_free_default,(png_structp png_ptr,
    png_voidp ptr),,101);
1456
#endif
1457

1458
#ifdef PNG_ERROR_TEXT_SUPPORTED
A
Andreas Dilger 已提交
1459
/* Fatal error in PNG image of libpng - can't continue */
1460 1461
extern PNG_EXPORT(void,png_error,(png_structp png_ptr,
    png_const_charp error_message),PNG_NORETURN,102);
G
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1462

1463
/* The same, but the chunk name is prepended to the error string. */
1464 1465
extern PNG_EXPORT(void,png_chunk_error,(png_structp png_ptr,
    png_const_charp error_message),PNG_NORETURN,103);
1466

1467 1468
#else
/* Fatal error in PNG image of libpng - can't continue */
1469
extern PNG_EXPORT(void,png_err,(png_structp png_ptr),PNG_NORETURN,104);
1470 1471
#endif

G
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1472
/* Non-fatal error in libpng.  Can continue, but may have a problem. */
1473 1474
extern PNG_EXPORT(void,png_warning,(png_structp png_ptr,
    png_const_charp warning_message),,105);
A
Andreas Dilger 已提交
1475

1476
/* Non-fatal error in libpng, chunk name is prepended to message. */
1477 1478
extern PNG_EXPORT(void,png_chunk_warning,(png_structp png_ptr,
    png_const_charp warning_message),,106);
1479

1480 1481 1482
#ifdef PNG_BENIGN_ERRORS_SUPPORTED
/* Benign error in libpng.  Can continue, but may have a problem.
 * User can choose whether to handle as a fatal error or as a warning. */
1483
#  undef png_benign_error
1484 1485
extern PNG_EXPORT(void,png_benign_error,(png_structp png_ptr,
    png_const_charp warning_message),,107);
1486 1487

/* Same, chunk name is prepended to message. */
1488
#  undef png_chunk_benign_error
1489 1490
extern PNG_EXPORT(void,png_chunk_benign_error,(png_structp png_ptr,
    png_const_charp warning_message),,108);
1491

1492 1493
extern PNG_EXPORT(void,png_set_benign_errors,(png_structp png_ptr,
    int allowed),,109);
1494 1495 1496 1497 1498 1499 1500 1501
#else
#  ifdef PNG_ALLOW_BENIGN_ERRORS
#    define png_benign_error png_warning
#    define png_chunk_benign_error png_chunk_warning
#  else
#    define png_benign_error png_error
#    define png_chunk_benign_error png_chunk_error
#  endif
1502 1503
#endif

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1504 1505 1506 1507 1508 1509 1510 1511 1512 1513 1514 1515
/* The png_set_<chunk> functions are for storing values in the png_info_struct.
 * Similarly, the png_get_<chunk> calls are used to read values from the
 * png_info_struct, either storing the parameters in the passed variables, or
 * setting pointers into the png_info_struct where the data is stored.  The
 * png_get_<chunk> functions return a non-zero value if the data was available
 * in info_ptr, or return zero and do not change any of the parameters if the
 * data was not available.
 *
 * These functions should be used instead of directly accessing png_info
 * to avoid problems with future changes in the size and internal layout of
 * png_info_struct.
 */
1516
/* Returns "flag" if chunk data is valid in info_ptr. */
1517 1518
extern PNG_EXPORT(png_uint_32,png_get_valid,(png_structp png_ptr,
    png_infop info_ptr, png_uint_32 flag),,110);
A
Andreas Dilger 已提交
1519

1520
/* Returns number of bytes needed to hold a transformed row. */
1521 1522
extern PNG_EXPORT(png_size_t,png_get_rowbytes,(png_structp png_ptr,
    png_infop info_ptr),,111);
A
Andreas Dilger 已提交
1523

1524
#ifdef PNG_INFO_IMAGE_SUPPORTED
1525
/* Returns row_pointers, which is an array of pointers to scanlines that was
1526 1527
 * returned from png_read_png().
 */
1528 1529
extern PNG_EXPORT(png_bytepp,png_get_rows,(png_structp png_ptr,
    png_infop info_ptr),,112);
1530
/* Set row_pointers, which is an array of pointers to scanlines for use
1531 1532
 * by png_write_png().
 */
1533 1534
extern PNG_EXPORT(void,png_set_rows,(png_structp png_ptr, png_infop info_ptr,
    png_bytepp row_pointers),,113);
1535 1536
#endif

1537
/* Returns number of color channels in image. */
1538 1539
extern PNG_EXPORT(png_byte,png_get_channels,(png_structp png_ptr,
    png_infop info_ptr),,114);
A
Andreas Dilger 已提交
1540

1541 1542
#ifdef PNG_EASY_ACCESS_SUPPORTED
/* Returns image width in pixels. */
1543 1544
extern PNG_EXPORT(png_uint_32, png_get_image_width,(png_structp png_ptr,
    png_infop info_ptr),,115);
1545 1546

/* Returns image height in pixels. */
1547 1548
extern PNG_EXPORT(png_uint_32, png_get_image_height,(png_structp png_ptr,
    png_infop info_ptr),,116);
1549 1550

/* Returns image bit_depth. */
1551 1552
extern PNG_EXPORT(png_byte, png_get_bit_depth,(png_structp png_ptr,
    png_infop info_ptr),,117);
1553 1554

/* Returns image color_type. */
1555 1556
extern PNG_EXPORT(png_byte, png_get_color_type,(png_structp png_ptr,
    png_infop info_ptr),,118);
1557 1558

/* Returns image filter_type. */
1559 1560
extern PNG_EXPORT(png_byte, png_get_filter_type,(png_structp png_ptr,
    png_infop info_ptr),,119);
1561 1562

/* Returns image interlace_type. */
1563 1564
extern PNG_EXPORT(png_byte, png_get_interlace_type,(png_structp png_ptr,
    png_infop info_ptr),,120);
1565 1566

/* Returns image compression_type. */
1567 1568
extern PNG_EXPORT(png_byte, png_get_compression_type,(png_structp png_ptr,
    png_infop info_ptr),,121);
1569 1570

/* Returns image resolution in pixels per meter, from pHYs chunk data. */
1571 1572 1573 1574 1575 1576
extern PNG_EXPORT(png_uint_32, png_get_pixels_per_meter,(png_structp png_ptr,
    png_infop info_ptr),,122);
extern PNG_EXPORT(png_uint_32, png_get_x_pixels_per_meter,
    (png_structp png_ptr, png_infop info_ptr),,123);
extern PNG_EXPORT(png_uint_32, png_get_y_pixels_per_meter,
    (png_structp png_ptr, png_infop info_ptr),,124);
1577 1578

/* Returns pixel aspect ratio, computed from pHYs chunk data.  */
1579
#  ifdef PNG_FLOATING_POINT_SUPPORTED
1580 1581
extern PNG_EXPORT(float, png_get_pixel_aspect_ratio,
    (png_structp png_ptr, png_infop info_ptr),,125);
1582
#  endif
1583 1584

/* Returns image x, y offset in pixels or microns, from oFFs chunk data. */
1585 1586 1587 1588 1589 1590 1591 1592
extern PNG_EXPORT(png_int_32, png_get_x_offset_pixels,
    (png_structp png_ptr, png_infop info_ptr),,126);
extern PNG_EXPORT(png_int_32, png_get_y_offset_pixels,
    (png_structp png_ptr, png_infop info_ptr),,127);
extern PNG_EXPORT(png_int_32, png_get_x_offset_microns,
    (png_structp png_ptr, png_infop info_ptr),,128);
extern PNG_EXPORT(png_int_32, png_get_y_offset_microns,
    (png_structp png_ptr, png_infop info_ptr),,129);
1593 1594 1595

#endif /* PNG_EASY_ACCESS_SUPPORTED */

A
Andreas Dilger 已提交
1596
/* Returns pointer to signature string read from PNG header */
1597 1598
extern PNG_EXPORT(png_bytep,png_get_signature,(png_structp png_ptr,
    png_infop info_ptr),,130);
A
Andreas Dilger 已提交
1599

1600
#ifdef PNG_bKGD_SUPPORTED
1601 1602
extern PNG_EXPORT(png_uint_32,png_get_bKGD,(png_structp png_ptr,
    png_infop info_ptr, png_color_16p *background),,131);
1603
#endif
A
Andreas Dilger 已提交
1604

1605
#ifdef PNG_bKGD_SUPPORTED
1606 1607
extern PNG_EXPORT(void,png_set_bKGD,(png_structp png_ptr,
    png_infop info_ptr, png_color_16p background),,132);
1608
#endif
A
Andreas Dilger 已提交
1609

1610
#ifdef PNG_cHRM_SUPPORTED
1611
#  ifdef PNG_FLOATING_POINT_SUPPORTED
1612 1613 1614 1615
extern PNG_EXPORT(png_uint_32,png_get_cHRM,(png_structp png_ptr,
    png_infop info_ptr, double *white_x, double *white_y,
    double *red_x, double *red_y, double *green_x, double *green_y,
    double *blue_x, double *blue_y),,133);
1616 1617
#  endif
#  ifdef PNG_FIXED_POINT_SUPPORTED
1618
extern PNG_EXPORT(png_uint_32,png_get_cHRM_fixed,(png_structp png_ptr,
1619 1620 1621 1622
    png_infop info_ptr,
    png_fixed_point *int_white_x, png_fixed_point *int_white_y,
    png_fixed_point *int_red_x, png_fixed_point *int_red_y,
    png_fixed_point *int_green_x, png_fixed_point *int_green_y,
1623
    png_fixed_point *int_blue_x, png_fixed_point *int_blue_y),,134);
1624
#  endif
1625
#endif
A
Andreas Dilger 已提交
1626

1627
#ifdef PNG_cHRM_SUPPORTED
1628
#  ifdef PNG_FLOATING_POINT_SUPPORTED
1629
extern PNG_EXPORT(void,png_set_cHRM,(png_structp png_ptr,
1630 1631
    png_infop info_ptr, double white_x, double white_y,
    double red_x, double red_y, double green_x, double green_y,
1632
    double blue_x, double blue_y),,135);
1633 1634
#  endif
#  ifdef PNG_FIXED_POINT_SUPPORTED
1635
extern PNG_EXPORT(void,png_set_cHRM_fixed,(png_structp png_ptr,
1636 1637 1638 1639
    png_infop info_ptr,
    png_fixed_point int_white_x, png_fixed_point int_white_y,
    png_fixed_point int_red_x, png_fixed_point int_red_y,
    png_fixed_point int_green_x, png_fixed_point int_green_y,
1640
    png_fixed_point int_blue_x, png_fixed_point int_blue_y),,136);
1641
#  endif
1642
#endif
A
Andreas Dilger 已提交
1643

1644
#ifdef PNG_gAMA_SUPPORTED
1645
#  ifdef PNG_FLOATING_POINT_SUPPORTED
1646 1647
extern PNG_EXPORT(png_uint_32,png_get_gAMA,(png_structp png_ptr,
    png_infop info_ptr, double *file_gamma),,137);
1648
#  endif
1649 1650
extern PNG_EXPORT(png_uint_32,png_get_gAMA_fixed,(png_structp png_ptr,
    png_infop info_ptr, png_fixed_point *int_file_gamma),,138);
1651
#endif
G
Guy Schalnat 已提交
1652

1653
#ifdef PNG_gAMA_SUPPORTED
1654
#  ifdef PNG_FLOATING_POINT_SUPPORTED
1655 1656
extern PNG_EXPORT(void,png_set_gAMA,(png_structp png_ptr,
    png_infop info_ptr, double file_gamma),,139);
1657
#  endif
1658 1659
extern PNG_EXPORT(void,png_set_gAMA_fixed,(png_structp png_ptr,
    png_infop info_ptr, png_fixed_point int_file_gamma),,140);
1660
#endif
A
Andreas Dilger 已提交
1661

1662
#ifdef PNG_hIST_SUPPORTED
1663 1664
extern PNG_EXPORT(png_uint_32,png_get_hIST,(png_structp png_ptr,
    png_infop info_ptr, png_uint_16p *hist),,141);
1665
#endif
A
Andreas Dilger 已提交
1666

1667
#ifdef PNG_hIST_SUPPORTED
1668 1669
extern PNG_EXPORT(void,png_set_hIST,(png_structp png_ptr,
    png_infop info_ptr, png_uint_16p hist),,142);
1670
#endif
A
Andreas Dilger 已提交
1671

1672
extern PNG_EXPORT(png_uint_32,png_get_IHDR,(png_structp png_ptr,
1673 1674
    png_infop info_ptr, png_uint_32 *width, png_uint_32 *height,
    int *bit_depth, int *color_type, int *interlace_method,
1675
    int *compression_method, int *filter_method),,143);
1676

1677
extern PNG_EXPORT(void,png_set_IHDR,(png_structp png_ptr,
1678 1679
    png_infop info_ptr, png_uint_32 width, png_uint_32 height, int bit_depth,
    int color_type, int interlace_method, int compression_method,
1680
    int filter_method),,144);
A
Andreas Dilger 已提交
1681

1682
#ifdef PNG_oFFs_SUPPORTED
1683
extern PNG_EXPORT(png_uint_32,png_get_oFFs,(png_structp png_ptr,
1684
    png_infop info_ptr, png_int_32 *offset_x, png_int_32 *offset_y,
1685
    int *unit_type),,145);
1686
#endif
A
Andreas Dilger 已提交
1687

1688
#ifdef PNG_oFFs_SUPPORTED
1689
extern PNG_EXPORT(void,png_set_oFFs,(png_structp png_ptr,
1690
    png_infop info_ptr, png_int_32 offset_x, png_int_32 offset_y,
1691
    int unit_type),,146);
1692
#endif
A
Andreas Dilger 已提交
1693

1694
#ifdef PNG_pCAL_SUPPORTED
1695
extern PNG_EXPORT(png_uint_32,png_get_pCAL,(png_structp png_ptr,
1696
    png_infop info_ptr, png_charp *purpose, png_int_32 *X0, png_int_32 *X1,
1697
    int *type, int *nparams, png_charp *units, png_charpp *params),,147);
1698
#endif
A
Andreas Dilger 已提交
1699

1700
#ifdef PNG_pCAL_SUPPORTED
1701
extern PNG_EXPORT(void,png_set_pCAL,(png_structp png_ptr,
1702
    png_infop info_ptr, png_charp purpose, png_int_32 X0, png_int_32 X1,
1703
    int type, int nparams, png_charp units, png_charpp params),,148);
1704 1705
#endif

1706
#ifdef PNG_pHYs_SUPPORTED
1707 1708 1709
extern PNG_EXPORT(png_uint_32,png_get_pHYs,(png_structp png_ptr,
    png_infop info_ptr, png_uint_32 *res_x, png_uint_32 *res_y,
    int *unit_type),,149);
1710
#endif
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Andreas Dilger 已提交
1711

1712
#ifdef PNG_pHYs_SUPPORTED
1713 1714 1715
extern PNG_EXPORT(void,png_set_pHYs,(png_structp png_ptr,
    png_infop info_ptr, png_uint_32 res_x, png_uint_32 res_y,
    int unit_type),,150);
1716
#endif
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Andreas Dilger 已提交
1717

1718 1719
extern PNG_EXPORT(png_uint_32,png_get_PLTE,(png_structp png_ptr,
    png_infop info_ptr, png_colorp *palette, int *num_palette),,151);
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Andreas Dilger 已提交
1720

1721 1722
extern PNG_EXPORT(void,png_set_PLTE,(png_structp png_ptr,
    png_infop info_ptr, png_colorp palette, int num_palette),,152);
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Andreas Dilger 已提交
1723

1724
#ifdef PNG_sBIT_SUPPORTED
1725 1726
extern PNG_EXPORT(png_uint_32,png_get_sBIT,(png_structp png_ptr,
    png_infop info_ptr, png_color_8p *sig_bit),,153);
1727
#endif
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Andreas Dilger 已提交
1728

1729
#ifdef PNG_sBIT_SUPPORTED
1730 1731
extern PNG_EXPORT(void,png_set_sBIT,(png_structp png_ptr,
    png_infop info_ptr, png_color_8p sig_bit),,154);
1732
#endif
A
Andreas Dilger 已提交
1733

1734
#ifdef PNG_sRGB_SUPPORTED
1735 1736
extern PNG_EXPORT(png_uint_32,png_get_sRGB,(png_structp png_ptr,
    png_infop info_ptr, int *intent),,155);
1737
#endif
1738

1739
#ifdef PNG_sRGB_SUPPORTED
1740 1741 1742 1743
extern PNG_EXPORT(void,png_set_sRGB,(png_structp png_ptr,
    png_infop info_ptr, int intent),,156);
extern PNG_EXPORT(void,png_set_sRGB_gAMA_and_cHRM,(png_structp png_ptr,
    png_infop info_ptr, int intent),,157);
1744 1745
#endif

1746
#ifdef PNG_iCCP_SUPPORTED
1747
extern PNG_EXPORT(png_uint_32,png_get_iCCP,(png_structp png_ptr,
1748
    png_infop info_ptr, png_charpp name, int *compression_type,
1749
    png_charpp profile, png_uint_32 *proflen),,158);
1750
    /* Note to maintainer: profile should be png_bytepp */
1751 1752
#endif

1753
#ifdef PNG_iCCP_SUPPORTED
1754
extern PNG_EXPORT(void,png_set_iCCP,(png_structp png_ptr,
1755
    png_infop info_ptr, png_charp name, int compression_type,
1756
    png_charp profile, png_uint_32 proflen),,159);
1757
    /* Note to maintainer: profile should be png_bytep */
1758 1759
#endif

1760
#ifdef PNG_sPLT_SUPPORTED
1761 1762
extern PNG_EXPORT(png_uint_32,png_get_sPLT,(png_structp png_ptr,
    png_infop info_ptr, png_sPLT_tpp entries),,160);
1763 1764
#endif

1765
#ifdef PNG_sPLT_SUPPORTED
1766 1767
extern PNG_EXPORT(void,png_set_sPLT,(png_structp png_ptr,
    png_infop info_ptr, png_sPLT_tp entries, int nentries),,161);
1768 1769
#endif

1770
#ifdef PNG_TEXT_SUPPORTED
1771
/* png_get_text also returns the number of text chunks in *num_text */
1772 1773
extern PNG_EXPORT(png_uint_32,png_get_text,(png_structp png_ptr,
    png_infop info_ptr, png_textp *text_ptr, int *num_text),,162);
1774
#endif
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Andreas Dilger 已提交
1775

1776 1777 1778 1779 1780
/* Note while png_set_text() will accept a structure whose text,
 * language, and  translated keywords are NULL pointers, the structure
 * returned by png_get_text will always contain regular
 * zero-terminated C strings.  They might be empty strings but
 * they will never be NULL pointers.
1781 1782
 */

1783
#ifdef PNG_TEXT_SUPPORTED
1784 1785
extern PNG_EXPORT(void,png_set_text,(png_structp png_ptr,
    png_infop info_ptr, png_textp text_ptr, int num_text),,163);
1786
#endif
A
Andreas Dilger 已提交
1787

1788
#ifdef PNG_tIME_SUPPORTED
1789 1790
extern PNG_EXPORT(png_uint_32,png_get_tIME,(png_structp png_ptr,
    png_infop info_ptr, png_timep *mod_time),,164);
1791
#endif
A
Andreas Dilger 已提交
1792

1793
#ifdef PNG_tIME_SUPPORTED
1794 1795
extern PNG_EXPORT(void,png_set_tIME,(png_structp png_ptr,
    png_infop info_ptr, png_timep mod_time),,165);
1796
#endif
A
Andreas Dilger 已提交
1797

1798
#ifdef PNG_tRNS_SUPPORTED
1799 1800 1801
extern PNG_EXPORT(png_uint_32,png_get_tRNS,(png_structp png_ptr,
    png_infop info_ptr, png_bytep *trans_alpha, int *num_trans,
    png_color_16p *trans_color),,166);
1802 1803
#endif

1804
#ifdef PNG_tRNS_SUPPORTED
1805 1806 1807
extern PNG_EXPORT(void,png_set_tRNS,(png_structp png_ptr,
    png_infop info_ptr, png_bytep trans_alpha, int num_trans,
    png_color_16p trans_color),,167);
1808 1809
#endif

1810
#ifdef PNG_sCAL_SUPPORTED
1811
#  ifdef PNG_FLOATING_POINT_SUPPORTED
1812 1813
extern PNG_EXPORT(png_uint_32,png_get_sCAL,(png_structp png_ptr,
    png_infop info_ptr, int *unit, double *width, double *height),,168);
1814 1815
#  else
#    ifdef PNG_FIXED_POINT_SUPPORTED
1816 1817 1818
extern PNG_EXPORT(png_uint_32,png_get_sCAL_s,(png_structp png_ptr,
    png_infop info_ptr, int *unit, png_charpp swidth,
    png_charpp sheight),,169);
1819 1820
#    endif
#  endif
1821
#endif /* PNG_sCAL_SUPPORTED */
1822

1823
#ifdef PNG_sCAL_SUPPORTED
1824
#  ifdef PNG_FLOATING_POINT_SUPPORTED
1825 1826
extern PNG_EXPORT(void,png_set_sCAL,(png_structp png_ptr,
    png_infop info_ptr, int unit, double width, double height),,170);
1827 1828
#  else
#    ifdef PNG_FIXED_POINT_SUPPORTED
1829 1830 1831
extern PNG_EXPORT(void,png_set_sCAL_s,(png_structp png_ptr,
    png_infop info_ptr, int unit, png_charp swidth,
    png_charp sheight),,171);
1832 1833
#    endif
#  endif
1834
#endif /* PNG_sCAL_SUPPORTED || PNG_WRITE_sCAL_SUPPORTED */
1835

1836 1837
#ifdef PNG_HANDLE_AS_UNKNOWN_SUPPORTED
/* Provide a list of chunks and how they are to be handled, if the built-in
1838 1839 1840
   handling or default unknown chunk handling is not desired.  Any chunks not
   listed will be handled in the default manner.  The IHDR and IEND chunks
   must not be listed.
1841
      keep = 0: follow default behaviour
1842 1843 1844 1845
           = 1: do not keep
           = 2: keep only if safe-to-copy
           = 3: keep even if unsafe-to-copy
*/
1846 1847
extern PNG_EXPORT(void, png_set_keep_unknown_chunks,(png_structp png_ptr,
    int keep, png_bytep chunk_list, int num_chunks),,172);
1848
extern PNG_EXPORT(int,png_handle_as_unknown,(png_structp png_ptr,
1849
    png_bytep chunk_name),,173);
1850
#endif
1851
#ifdef PNG_UNKNOWN_CHUNKS_SUPPORTED
1852 1853 1854 1855 1856 1857 1858 1859
extern PNG_EXPORT(void, png_set_unknown_chunks,(png_structp png_ptr,
    png_infop info_ptr, png_unknown_chunkp unknowns,
    int num_unknowns),,174);
extern PNG_EXPORT(void, png_set_unknown_chunk_location,
    (png_structp png_ptr, png_infop info_ptr, int chunk,
    int location),,175);
extern PNG_EXPORT(png_uint_32,png_get_unknown_chunks,(png_structp png_ptr,
    png_infop info_ptr, png_unknown_chunkpp entries),,176);
1860 1861
#endif

1862
/* Png_free_data() will turn off the "valid" flag for anything it frees.
1863 1864 1865
 * If you need to turn it off for a chunk that your application has freed,
 * you can use png_set_invalid(png_ptr, info_ptr, PNG_INFO_CHNK);
 */
1866 1867
extern PNG_EXPORT(void, png_set_invalid,(png_structp png_ptr,
    png_infop info_ptr, int mask),,177);
1868

1869
#ifdef PNG_INFO_IMAGE_SUPPORTED
1870
/* The "params" pointer is currently not used and is for future expansion. */
1871 1872 1873 1874 1875 1876 1877 1878 1879 1880
extern PNG_EXPORT(void, png_read_png,(png_structp png_ptr,
    png_infop info_ptr, int transforms, png_voidp params),,178);
extern PNG_EXPORT(void, png_write_png,(png_structp png_ptr,
    png_infop info_ptr, int transforms, png_voidp params),,179);
#endif

extern PNG_EXPORT(png_charp,png_get_copyright,(png_structp png_ptr),,180);
extern PNG_EXPORT(png_charp,png_get_header_ver,(png_structp png_ptr),,181);
extern PNG_EXPORT(png_charp,png_get_header_version,(png_structp png_ptr),,182);
extern PNG_EXPORT(png_charp,png_get_libpng_ver,(png_structp png_ptr),,183);
1881

1882
#ifdef PNG_MNG_FEATURES_SUPPORTED
1883 1884
extern PNG_EXPORT(png_uint_32,png_permit_mng_features,(png_structp png_ptr,
    png_uint_32 mng_features_permitted),,184);
1885 1886
#endif

1887 1888 1889 1890 1891 1892
/* For use in png_set_keep_unknown, added to version 1.2.6 */
#define PNG_HANDLE_CHUNK_AS_DEFAULT   0
#define PNG_HANDLE_CHUNK_NEVER        1
#define PNG_HANDLE_CHUNK_IF_SAFE      2
#define PNG_HANDLE_CHUNK_ALWAYS       3

1893
/* Strip the prepended error numbers ("#nnn ") from error and warning
1894 1895
 * messages before passing them to the error or warning handler.
 */
1896
#ifdef PNG_ERROR_NUMBERS_SUPPORTED
1897 1898
extern PNG_EXPORT(void,png_set_strip_error_numbers,(png_structp png_ptr,
    png_uint_32 strip_mode),,185);
1899
#endif
1900

1901
/* Added in libpng-1.2.6 */
1902
#ifdef PNG_SET_USER_LIMITS_SUPPORTED
1903 1904 1905 1906 1907 1908
extern PNG_EXPORT(void,png_set_user_limits,(png_structp png_ptr,
    png_uint_32 user_width_max, png_uint_32 user_height_max),,186);
extern PNG_EXPORT(png_uint_32,png_get_user_width_max,
    (png_structp png_ptr),,187);
extern PNG_EXPORT(png_uint_32,png_get_user_height_max,
    (png_structp png_ptr),,188);
1909
/* Added in libpng-1.4.0 */
1910 1911 1912 1913
extern PNG_EXPORT(void,png_set_chunk_cache_max,(png_structp png_ptr,
    png_uint_32 user_chunk_cache_max),,189);
extern PNG_EXPORT(png_uint_32,png_get_chunk_cache_max,
    (png_structp png_ptr),,190);
1914
/* Added in libpng-1.4.1 */
1915 1916 1917 1918
extern PNG_EXPORT(void,png_set_chunk_malloc_max,(png_structp png_ptr,
    png_alloc_size_t user_chunk_cache_max),,191);
extern PNG_EXPORT(png_alloc_size_t,png_get_chunk_malloc_max,
    (png_structp png_ptr),,192);
1919 1920
#endif

1921
#if defined(PNG_INCH_CONVERSIONS_SUPPORTED) && defined(PNG_FLOATING_POINT_SUPPORTED)
1922 1923
PNG_EXPORT(png_uint_32,png_get_pixels_per_inch,(png_structp png_ptr,
    png_infop info_ptr),,193);
1924

1925 1926
PNG_EXPORT(png_uint_32,png_get_x_pixels_per_inch,(png_structp png_ptr,
    png_infop info_ptr),,194);
1927

1928 1929
PNG_EXPORT(png_uint_32,png_get_y_pixels_per_inch,(png_structp png_ptr,
    png_infop info_ptr),,195);
1930

1931 1932
PNG_EXPORT(float,png_get_x_offset_inches,(png_structp png_ptr,
    png_infop info_ptr),,196);
1933

1934 1935
PNG_EXPORT(float,png_get_y_offset_inches,(png_structp png_ptr,
    png_infop info_ptr),,197);
1936

1937
#  ifdef PNG_pHYs_SUPPORTED
1938 1939 1940
PNG_EXPORT(png_uint_32,png_get_pHYs_dpi,(png_structp png_ptr,
    png_infop info_ptr, png_uint_32 *res_x, png_uint_32 *res_y,
    int *unit_type),,198);
1941
#  endif /* PNG_pHYs_SUPPORTED */
1942
#endif  /* PNG_INCH_CONVERSIONS_SUPPORTED && PNG_FLOATING_POINT_SUPPORTED */
1943

1944 1945
/* Added in libpng-1.4.0 */
#ifdef PNG_IO_STATE_SUPPORTED
1946
extern PNG_EXPORT(png_uint_32,png_get_io_state,(png_structp png_ptr),,199);
1947

1948
extern PNG_EXPORT(png_bytep,png_get_io_chunk_name,(png_structp png_ptr),,200);
1949 1950

/* The flags returned by png_get_io_state() are the following: */
1951 1952 1953 1954 1955 1956 1957 1958 1959
#  define PNG_IO_NONE        0x0000   /* no I/O at this moment */
#  define PNG_IO_READING     0x0001   /* currently reading */
#  define PNG_IO_WRITING     0x0002   /* currently writing */
#  define PNG_IO_SIGNATURE   0x0010   /* currently at the file signature */
#  define PNG_IO_CHUNK_HDR   0x0020   /* currently at the chunk header */
#  define PNG_IO_CHUNK_DATA  0x0040   /* currently at the chunk data */
#  define PNG_IO_CHUNK_CRC   0x0080   /* currently at the chunk crc */
#  define PNG_IO_MASK_OP     0x000f   /* current operation: reading/writing */
#  define PNG_IO_MASK_LOC    0x00f0   /* current location: sig/hdr/data/crc */
1960 1961
#endif /* ?PNG_IO_STATE_SUPPORTED */

1962 1963 1964
/* Maintainer: Put new public prototypes here ^, in libpng.3, and project
 * defs
 */
1965

1966
#ifdef PNG_READ_COMPOSITE_NODIV_SUPPORTED
1967 1968 1969
/* With these routines we avoid an integer divide, which will be slower on
 * most machines.  However, it does take more operations than the corresponding
 * divide method, so it may be slower on a few RISC systems.  There are two
1970 1971 1972 1973 1974 1975 1976 1977 1978
 * shifts (by 8 or 16 bits) and an addition, versus a single integer divide.
 *
 * Note that the rounding factors are NOT supposed to be the same!  128 and
 * 32768 are correct for the NODIV code; 127 and 32767 are correct for the
 * standard method.
 *
 * [Optimized code by Greg Roelofs and Mark Adler...blame us for bugs. :-) ]
 */

1979
 /* fg and bg should be in `gamma 1.0' space; alpha is the opacity */
1980

1981 1982 1983 1984 1985
#  define png_composite(composite, fg, alpha, bg)         \
     { png_uint_16 temp = (png_uint_16)((png_uint_16)(fg) \
           * (png_uint_16)(alpha)                         \
           + (png_uint_16)(bg)*(png_uint_16)(255          \
           - (png_uint_16)(alpha)) + (png_uint_16)128);   \
1986
       (composite) = (png_byte)((temp + (temp >> 8)) >> 8); }
1987

1988 1989 1990 1991 1992
#  define png_composite_16(composite, fg, alpha, bg)       \
     { png_uint_32 temp = (png_uint_32)((png_uint_32)(fg)  \
           * (png_uint_32)(alpha)                          \
           + (png_uint_32)(bg)*(png_uint_32)(65535L        \
           - (png_uint_32)(alpha)) + (png_uint_32)32768L); \
1993 1994
       (composite) = (png_uint_16)((temp + (temp >> 16)) >> 16); }

1995
#else  /* Standard method using integer division */
1996

1997 1998
#  define png_composite(composite, fg, alpha, bg)                          \
     (composite) = (png_byte)(((png_uint_16)(fg) * (png_uint_16)(alpha) +  \
1999 2000
     (png_uint_16)(bg) * (png_uint_16)(255 - (png_uint_16)(alpha)) +       \
     (png_uint_16)127) / 255)
2001 2002

#  define png_composite_16(composite, fg, alpha, bg)                         \
2003
     (composite) = (png_uint_16)(((png_uint_32)(fg) * (png_uint_32)(alpha) + \
2004
     (png_uint_32)(bg)*(png_uint_32)(65535L - (png_uint_32)(alpha)) +        \
2005
     (png_uint_32)32767) / (png_uint_32)65535L)
2006 2007
#endif /* PNG_READ_COMPOSITE_NODIV_SUPPORTED */

2008 2009 2010 2011
#ifdef PNG_USE_READ_MACROS
/* Inline macros to do direct reads of bytes from the input buffer.
 * The png_get_int_32() routine assumes we are using two's complement
 * format for negative values, which is almost certainly true.
2012
 */
2013 2014 2015 2016 2017 2018 2019 2020
#  define png_get_uint_32(buf) \
     (((png_uint_32)(*(buf)) << 24) + \
      ((png_uint_32)(*((buf) + 1)) << 16) + \
      ((png_uint_32)(*((buf) + 2)) << 8) + \
      ((png_uint_32)(*((buf) + 3))))
#  define png_get_uint_16(buf) \
     (((png_uint_32)(*(buf)) << 8) + \
      ((png_uint_32)(*((buf) + 1))))
2021 2022
#  ifdef PNG_GET_INT_32_SUPPORTED
#    define png_get_int_32(buf) \
2023 2024 2025 2026
     (((png_int_32)(*(buf)) << 24) + \
      ((png_int_32)(*((buf) + 1)) << 16) + \
      ((png_int_32)(*((buf) + 2)) << 8) + \
      ((png_int_32)(*((buf) + 3))))
2027
#  endif
2028
#endif
2029 2030

#ifdef PNG_READ_INT_FUNCTIONS_SUPPORTED
2031 2032
extern PNG_EXPORT(png_uint_32,png_get_uint_32,(png_bytep buf),,201);
extern PNG_EXPORT(png_uint_16,png_get_uint_16,(png_bytep buf),,202);
2033 2034
#endif
#ifdef PNG_GET_INT_32_SUPPORTED
2035
extern PNG_EXPORT(png_int_32,png_get_int_32,(png_bytep buf),,203);
2036 2037
#endif

2038 2039
extern PNG_EXPORT(png_uint_32,png_get_uint_31,(png_structp png_ptr,
    png_bytep buf),,204);
2040 2041
/* No png_get_int_16 -- may be added if there's a real need for it. */

2042
/* Place a 32-bit number into a buffer in PNG byte order (big-endian). */
2043
#ifdef PNG_WRITE_INT_FUNCTIONS_SUPPORTED
2044
extern PNG_EXPORT(void,png_save_uint_32,(png_bytep buf, png_uint_32 i),,205);
2045
#endif
2046
#ifdef PNG_SAVE_INT_32_SUPPORTED
2047
extern PNG_EXPORT(void,png_save_int_32,(png_bytep buf, png_int_32 i),,206);
2048
#endif
2049 2050 2051 2052 2053

/* Place a 16-bit number into a buffer in PNG byte order.
 * The parameter is declared unsigned int, not png_uint_16,
 * just to avoid potential problems on pre-ANSI C compilers.
 */
2054
#ifdef PNG_WRITE_INT_FUNCTIONS_SUPPORTED
2055
extern PNG_EXPORT(void,png_save_uint_16,(png_bytep buf, unsigned int i),,207);
2056
/* No png_save_int_16 -- may be added if there's a real need for it. */
2057
#endif
2058

2059 2060 2061 2062 2063 2064 2065
/* The last ordinal number (this is the *last* one, the next one to
 * use is one more than this.)
 */
#ifdef PNG_EXPORT_LAST_ORDINAL
  PNG_EXPORT_LAST_ORDINAL(207);
#endif

A
Andreas Dilger 已提交
2066 2067 2068 2069
#ifdef __cplusplus
}
#endif

2070
#endif /* PNG_VERSION_INFO_ONLY */
2071
/* Do not put anything past this line */
2072
#endif /* PNG_H */