png.h 86.7 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 1.5.0beta55 - November 11, 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 1.5.0beta55 - November 11, 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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 *    1.4.2                   14    10402  14.so.14.2[.0]
 *    1.4.3                   14    10403  14.so.14.3[.0]
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 *    1.5.0beta01-55          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-manual.txt or libpng.3 for more information.  The PNG
 * specification 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 1.5.0beta55, November 11, 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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 *    November 11, 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 1.5.0beta55 are Y2K compliant.  It is my belief that
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 *    earlier versions were also Y2K compliant.
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 *
 *    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-manual.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 "1.5.0beta55"
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#define PNG_HEADER_VERSION_STRING \
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     " libpng version 1.5.0beta55 - November 11, 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  55
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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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    /* If pnglibconf.h is missing, you can
     * copy scripts/pnglibconf.h.prebuilt to pnglibconf.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_SETJMP_SUPPORTED
#    include <setjmp.h>
#  endif

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/* Need the time information for converting tIME chunks, it
 * defines struct tm:
 */
#ifdef PNG_CONVERT_tIME_SUPPORTED
   /* "time.h" functions are not supported on all operating systems */
#  include <time.h>
#endif
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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
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 *
 * Run time configuration allows the application to choose between
 * implementations of certain arithmetic APIs.  The default is set
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 * 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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/* This triggers a compiler error in png.c, if png.c and png.h
 * do not agree upon the version number.
 */
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typedef char* png_libpng_version_1_5_0beta55;
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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;
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typedef PNG_CONST png_color FAR * png_const_colorp;
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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;
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typedef PNG_CONST png_color_16 FAR * png_const_color_16p;
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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;
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typedef PNG_CONST png_color_8 FAR * png_const_color_8p;
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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;
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typedef PNG_CONST png_sPLT_entry FAR * png_const_sPLT_entryp;
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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
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{
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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;
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typedef PNG_CONST png_sPLT_t FAR * png_const_sPLT_tp;
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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;
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typedef PNG_CONST png_text FAR * png_const_textp;
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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;
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typedef PNG_CONST png_time FAR * png_const_timep;
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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;
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typedef PNG_CONST png_unknown_chunk FAR * png_const_unknown_chunkp;
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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 are constants for fixed point values encoded in the
 * PNG specification manner (x100000)
 */
#define PNG_FP_1    100000
#define PNG_FP_HALF  50000

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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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/* Maximum number of entries in PLTE/sPLT/tRNS arrays */
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#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
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 * user read/write data functions.  Note that the 'write' function must not
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 * modify the buffer it is passed. The 'read' function, on the other hand, is
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 * expected to return the read data in the buffer.
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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) || \
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    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),);
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#endif
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813
#ifdef PNG_USER_CHUNKS_SUPPORTED
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typedef PNG_CALLBACK(int, *png_user_chunk_ptr, (png_structp,
    png_unknown_chunkp),);
816
#endif
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#ifdef PNG_UNKNOWN_CHUNKS_SUPPORTED
818
typedef PNG_CALLBACK(void, *png_unknown_chunk_ptr, (png_structp),);
819
#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
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 * of jmp_buf.  The function is required to be PNG_NORETURN.  (Note that
 * PNG_PTR_NORETURN is used here because current versions of the Microsoft
 * C compiler do not support the PNG_NORETURN attribute on a pointer.)
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 *
 * If you get a type warning from the compiler when linking against this line
 * then your compiler has 'longjmp' that does not match the requirements of the
 * compiler that built libpng.  You will have to write a wrapper function for
 * your compiler's longjmp and call png_set_longjmp_fn directly (not via the
 * png_jmpbuf macro.)
 *
 * If you get a warning here while building the library you will need to make
 * changes to ensure that pnglibconf.h records the calling convention used by
 * your compiler.  This may be very difficult - try using a different compiler
 * to build the library!
837
 */
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typedef PNG_FUNCTION(void,(PNGCAPI *png_longjmp_ptr),PNGARG((jmp_buf, int)),
   PNG_PTR_NORETURN);
840
#endif
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/* Transform masks for the high-level interface */
843 844
#define PNG_TRANSFORM_IDENTITY       0x0000    /* read and write */
#define PNG_TRANSFORM_STRIP_16       0x0001    /* read only */
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#define PNG_TRANSFORM_STRIP_ALPHA    0x0002    /* read only */
#define PNG_TRANSFORM_PACKING        0x0004    /* read and write */
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#define PNG_TRANSFORM_PACKSWAP       0x0008    /* read and write */
#define PNG_TRANSFORM_EXPAND         0x0010    /* read only */
849
#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 */
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#define PNG_TRANSFORM_SWAP_ENDIAN    0x0200    /* read and write */
854
#define PNG_TRANSFORM_INVERT_ALPHA   0x0400    /* read and write */
855
#define PNG_TRANSFORM_STRIP_FILLER   0x0800    /* write only */
856
/* Added to libpng-1.2.34 */
857
#define PNG_TRANSFORM_STRIP_FILLER_BEFORE PNG_TRANSFORM_STRIP_FILLER
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#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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/* Flags for MNG supported features */
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#define PNG_FLAG_MNG_EMPTY_PLTE     0x01
#define PNG_FLAG_MNG_FILTER_64      0x04
865
#define PNG_ALL_MNG_FEATURES        0x05
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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),);
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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-manual.txt for the
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 * 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 */
887
PNG_EXPORT(png_uint_32,png_access_version_number,(void),,1);
888

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889
/* Tell lib we have already handled the first <num_bytes> magic bytes.
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890 891
 * Handling more than 8 bytes from the beginning of the file is an error.
 */
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PNG_EXPORT(void,png_set_sig_bytes,(png_structp png_ptr, int num_bytes),,2);
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893 894 895 896 897 898

/* 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).
 */
899
PNG_EXPORT(int,png_sig_cmp,(png_const_bytep sig, png_size_t start,
900
    png_size_t num_to_check),,3);
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902 903 904 905 906
/* 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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907
/* Allocate and initialize png_ptr struct for reading, and any other memory. */
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908 909 910
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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911

912
/* Allocate and initialize png_ptr struct for writing, and any other memory */
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913 914 915
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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917
PNG_EXPORT(png_size_t,png_get_compression_buffer_size,(png_structp png_ptr),,6);
918

919
PNG_EXPORT(void,png_set_compression_buffer_size,(png_structp png_ptr,
920
    png_size_t size),,7);
921

922 923 924 925 926 927 928 929 930 931 932
/* 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.
 */
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933
PNG_EXPORT(jmp_buf*,png_set_longjmp_fn,(png_structp png_ptr,
934
    png_longjmp_ptr longjmp_fn, size_t jmp_buf_size),,8);
935
#  define png_jmpbuf(png_ptr) \
936
      (*png_set_longjmp_fn((png_ptr), longjmp, sizeof (jmp_buf)))
937 938
#else
#  define png_jmpbuf(png_ptr) \
939
      (LIBPNG_WAS_COMPILED_WITH__PNG_NO_SETJMP)
940
#endif
941 942 943 944 945
/* 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.
 */
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946
PNG_EXPORT(void,png_longjmp,(png_structp png_ptr, int val),PNG_NORETURN,9);
947

948
#ifdef PNG_READ_SUPPORTED
949
/* Reset the compression stream */
950
PNG_EXPORT(int,png_reset_zstream,(png_structp png_ptr),,10);
951
#endif
952

953
/* New functions added in libpng-1.0.2 (not enabled by default until 1.2.0) */
954
#ifdef PNG_USER_MEM_SUPPORTED
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955 956 957 958 959 960 961 962
PNG_EXPORT(png_structp,png_create_read_struct_2,(png_const_charp user_png_ver,
    png_voidp error_ptr, png_error_ptr error_fn, png_error_ptr warn_fn,
    png_voidp mem_ptr, png_malloc_ptr malloc_fn, png_free_ptr free_fn),
    PNG_ALLOCATED,11);
PNG_EXPORT(png_structp,png_create_write_struct_2,(png_const_charp user_png_ver,
    png_voidp error_ptr, png_error_ptr error_fn, png_error_ptr warn_fn,
    png_voidp mem_ptr, png_malloc_ptr malloc_fn, png_free_ptr free_fn),
    PNG_ALLOCATED,12);
963 964
#endif

965
/* Write the PNG file signature. */
966
PNG_EXPORT(void,png_write_sig,(png_structp png_ptr),,13);
967

968
/* Write a PNG chunk - size, type, (optional) data, CRC. */
969 970
PNG_EXPORT(void,png_write_chunk,(png_structp png_ptr, png_const_bytep
    chunk_name, png_const_bytep data, png_size_t length),,14);
971 972

/* Write the start of a PNG chunk - length and chunk name. */
973
PNG_EXPORT(void,png_write_chunk_start,(png_structp png_ptr,
974
    png_const_bytep chunk_name, png_uint_32 length),,15);
975 976

/* Write the data of a PNG chunk started with png_write_chunk_start(). */
977
PNG_EXPORT(void,png_write_chunk_data,(png_structp png_ptr, png_const_bytep data,
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978
    png_size_t length),,16);
979 980

/* Finish a chunk started with png_write_chunk_start() (includes CRC). */
981
PNG_EXPORT(void,png_write_chunk_end,(png_structp png_ptr),,17);
982

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983
/* Allocate and initialize the info structure */
984
PNG_EXPORT(png_infop,png_create_info_struct,(png_structp png_ptr),
985
    PNG_ALLOCATED,18);
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986

987
PNG_EXPORT(void,png_info_init_3,(png_infopp info_ptr,
988
    png_size_t png_info_struct_size),,19);
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989

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990
/* Writes all the PNG information before the image. */
991
PNG_EXPORT(void,png_write_info_before_PLTE,(png_structp png_ptr,
992
    png_infop info_ptr),,20);
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993
PNG_EXPORT(void,png_write_info,(png_structp png_ptr, png_infop info_ptr),,21);
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994

995
#ifdef PNG_SEQUENTIAL_READ_SUPPORTED
996
/* Read the information before the actual image data. */
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997
PNG_EXPORT(void,png_read_info,(png_structp png_ptr, png_infop info_ptr),,22);
998
#endif
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999

1000
#ifdef PNG_TIME_RFC1123_SUPPORTED
1001 1002
PNG_EXPORT(png_const_charp,png_convert_to_rfc1123,(png_structp png_ptr,
    png_const_timep ptime),,23);
1003
#endif
1004

1005
#ifdef PNG_CONVERT_tIME_SUPPORTED
1006
/* Convert from a struct tm to png_time */
1007
PNG_EXPORT(void,png_convert_from_struct_tm,(png_timep ptime,
1008
    PNG_CONST struct tm FAR * ttime),,24);
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1009

1010
/* Convert from time_t to png_time.  Uses gmtime() */
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1011
PNG_EXPORT(void,png_convert_from_time_t,(png_timep ptime, time_t ttime),,25);
1012
#endif /* PNG_CONVERT_tIME_SUPPORTED */
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1013

1014
#ifdef PNG_READ_EXPAND_SUPPORTED
1015
/* Expand data to 24-bit RGB, or 8-bit grayscale, with alpha if available. */
1016
PNG_EXPORT(void,png_set_expand,(png_structp png_ptr),,26);
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1017
PNG_EXPORT(void,png_set_expand_gray_1_2_4_to_8,(png_structp png_ptr),,27);
1018 1019
PNG_EXPORT(void,png_set_palette_to_rgb,(png_structp png_ptr),,28);
PNG_EXPORT(void,png_set_tRNS_to_alpha,(png_structp png_ptr),,29);
1020
#endif
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1022
#if defined(PNG_READ_BGR_SUPPORTED) || defined(PNG_WRITE_BGR_SUPPORTED)
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1023
/* Use blue, green, red order for pixels. */
1024
PNG_EXPORT(void,png_set_bgr,(png_structp png_ptr),,30);
1025
#endif
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1026

1027
#ifdef PNG_READ_GRAY_TO_RGB_SUPPORTED
1028
/* Expand the grayscale to 24-bit RGB if necessary. */
1029
PNG_EXPORT(void,png_set_gray_to_rgb,(png_structp png_ptr),,31);
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1030

1031
/* Reduce RGB to grayscale. */
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1032 1033 1034
PNG_FP_EXPORT(void,png_set_rgb_to_gray,(png_structp png_ptr, int error_action,
    double red, double green ),,32);
PNG_FIXED_EXPORT(void,png_set_rgb_to_gray_fixed,(png_structp png_ptr,
1035
    int error_action, png_fixed_point red, png_fixed_point green),,33);
1036

G
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1037
PNG_EXPORT(png_byte,png_get_rgb_to_gray_status,(png_structp png_ptr),,34);
1038
#endif
A
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1039

1040
PNG_EXPORT(void,png_build_grayscale_palette,(int bit_depth,
1041
    png_colorp palette),,35);
A
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1042

1043
#ifdef PNG_READ_STRIP_ALPHA_SUPPORTED
1044
PNG_EXPORT(void,png_set_strip_alpha,(png_structp png_ptr),,36);
1045
#endif
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1046

A
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1047 1048
#if defined(PNG_READ_SWAP_ALPHA_SUPPORTED) || \
    defined(PNG_WRITE_SWAP_ALPHA_SUPPORTED)
1049
PNG_EXPORT(void,png_set_swap_alpha,(png_structp png_ptr),,37);
1050
#endif
G
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1051

1052 1053
#if defined(PNG_READ_INVERT_ALPHA_SUPPORTED) || \
    defined(PNG_WRITE_INVERT_ALPHA_SUPPORTED)
1054
PNG_EXPORT(void,png_set_invert_alpha,(png_structp png_ptr),,38);
1055
#endif
1056

A
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1057
#if defined(PNG_READ_FILLER_SUPPORTED) || defined(PNG_WRITE_FILLER_SUPPORTED)
1058
/* Add a filler byte to 8-bit Gray or 24-bit RGB images. */
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1059 1060
PNG_EXPORT(void,png_set_filler,(png_structp png_ptr, png_uint_32 filler,
    int flags),,39);
A
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1061
/* The values of the PNG_FILLER_ defines should NOT be changed */
1062 1063
#  define PNG_FILLER_BEFORE 0
#  define PNG_FILLER_AFTER 1
1064
/* Add an alpha byte to 8-bit Gray or 24-bit RGB images. */
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1065 1066
PNG_EXPORT(void,png_set_add_alpha,(png_structp png_ptr, png_uint_32 filler,
    int flags),,40);
A
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1067
#endif /* PNG_READ_FILLER_SUPPORTED || PNG_WRITE_FILLER_SUPPORTED */
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1068

G
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1069
#if defined(PNG_READ_SWAP_SUPPORTED) || defined(PNG_WRITE_SWAP_SUPPORTED)
1070
/* Swap bytes in 16-bit depth files. */
1071
PNG_EXPORT(void,png_set_swap,(png_structp png_ptr),,41);
1072
#endif
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1073

G
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1074
#if defined(PNG_READ_PACK_SUPPORTED) || defined(PNG_WRITE_PACK_SUPPORTED)
1075
/* Use 1 byte per pixel in 1, 2, or 4-bit depth files. */
1076
PNG_EXPORT(void,png_set_packing,(png_structp png_ptr),,42);
1077
#endif
A
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1078

1079 1080
#if defined(PNG_READ_PACKSWAP_SUPPORTED) || \
    defined(PNG_WRITE_PACKSWAP_SUPPORTED)
A
Andreas Dilger 已提交
1081
/* Swap packing order of pixels in bytes. */
1082
PNG_EXPORT(void,png_set_packswap,(png_structp png_ptr),,43);
1083
#endif
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1084

G
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1085
#if defined(PNG_READ_SHIFT_SUPPORTED) || defined(PNG_WRITE_SHIFT_SUPPORTED)
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1086
/* Converts files to legal bit depths. */
1087 1088
PNG_EXPORT(void,png_set_shift,(png_structp png_ptr, png_const_color_8p
    true_bits),,44);
1089
#endif
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1090

G
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1091 1092
#if defined(PNG_READ_INTERLACING_SUPPORTED) || \
    defined(PNG_WRITE_INTERLACING_SUPPORTED)
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1093 1094 1095 1096 1097
/* Have the code handle the interlacing.  Returns the number of passes.
 * MUST be called before png_read_update_info or png_start_read_image, otherwise
 * it will not have the desired effect.  Note that it is still necessary to call
 * png_read_row or png_read_rows png_get_image_height times for each pass.
 */
1098
PNG_EXPORT(int,png_set_interlace_handling,(png_structp png_ptr),,45);
1099
#endif
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1100

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1101 1102 1103 1104 1105 1106 1107 1108 1109 1110 1111
#ifdef PNG_SEQUENTIAL_READ_SUPPORTED
/* Alternatively call this to get the number of rows in the current pass.  Call
 * this after png_read_update_info or png_start_read_image; if you call it
 * before it will just return the image height (which is also what it returns
 * for a non-interlaced image!).
 *
 * NOTE: you need to call these to find out how many times to call png_read_row
 * if you handle your own de-interlacing.
 */
PNG_EXPORT(int,png_get_num_passes,(png_structp png_ptr),,215);
PNG_EXPORT(png_uint_32,png_get_num_rows,(png_structp png_ptr),,216);
1112
PNG_EXPORT(png_uint_32,png_get_num_cols,(png_structp png_ptr),,218);
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1113 1114
#endif

G
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1115
#if defined(PNG_READ_INVERT_SUPPORTED) || defined(PNG_WRITE_INVERT_SUPPORTED)
1116
/* Invert monochrome files */
1117
PNG_EXPORT(void,png_set_invert_mono,(png_structp png_ptr),,46);
1118
#endif
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1119

1120
#ifdef PNG_READ_BACKGROUND_SUPPORTED
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1121
/* Handle alpha and tRNS by replacing with a background color. */
G
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1122
PNG_FP_EXPORT(void,png_set_background,(png_structp png_ptr,
1123 1124
    png_const_color_16p background_color, int background_gamma_code,
    int need_expand, double background_gamma),,47);
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1125
PNG_FIXED_EXPORT(void,png_set_background_fixed,(png_structp png_ptr,
1126 1127
    png_const_color_16p background_color, int background_gamma_code,
    int need_expand, png_fixed_point background_gamma),,217);
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1128 1129
#endif
#ifdef PNG_READ_BACKGROUND_SUPPORTED
1130 1131 1132 1133
#  define PNG_BACKGROUND_GAMMA_UNKNOWN 0
#  define PNG_BACKGROUND_GAMMA_SCREEN  1
#  define PNG_BACKGROUND_GAMMA_FILE    2
#  define PNG_BACKGROUND_GAMMA_UNIQUE  3
1134
#endif
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1135

1136
#ifdef PNG_READ_16_TO_8_SUPPORTED
1137
/* Strip the second byte of information from a 16-bit depth file. */
1138
PNG_EXPORT(void,png_set_strip_16,(png_structp png_ptr),,48);
1139
#endif
G
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1140

1141 1142
#ifdef PNG_READ_QUANTIZE_SUPPORTED
/* Turn on quantizing, and reduce the palette to the number of colors
1143 1144
 * available.
 */
G
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1145
PNG_EXPORT(void,png_set_quantize,(png_structp png_ptr, png_colorp palette,
1146
    int num_palette, int maximum_colors, png_const_uint_16p histogram,
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1147
    int full_quantize),,49);
1148
#endif
G
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1149

1150
#ifdef PNG_READ_GAMMA_SUPPORTED
G
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1151 1152 1153 1154 1155
/* The threshold on gamma processing is configurable but hard-wired into the
 * library.  The following is the floating point variant.
 */
#define PNG_GAMMA_THRESHOLD (PNG_GAMMA_THRESHOLD_FIXED*.00001)

1156
/* Handle gamma correction. Screen_gamma=(display_exponent) */
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1157 1158 1159 1160
PNG_FP_EXPORT(void,png_set_gamma,(png_structp png_ptr, double screen_gamma,
    double default_file_gamma),,50);
PNG_FIXED_EXPORT(void,png_set_gamma_fixed,(png_structp png_ptr,
    png_fixed_point screen_gamma, png_fixed_point default_file_gamma),,208);
1161
#endif
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1162

1163

1164
#ifdef PNG_WRITE_FLUSH_SUPPORTED
G
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1165
/* Set how many lines between output flushes - 0 for no flushing */
1166
PNG_EXPORT(void,png_set_flush,(png_structp png_ptr, int nrows),,51);
G
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1167
/* Flush the current PNG output buffer */
1168
PNG_EXPORT(void,png_write_flush,(png_structp png_ptr),,52);
1169
#endif
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1170

1171
/* Optional update palette with requested transformations */
1172
PNG_EXPORT(void,png_start_read_image,(png_structp png_ptr),,53);
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1173

1174
/* Optional call to update the users info structure */
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1175 1176
PNG_EXPORT(void,png_read_update_info,(png_structp png_ptr, png_infop info_ptr),,
    54);
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1177

1178
#ifdef PNG_SEQUENTIAL_READ_SUPPORTED
1179
/* Read one or more rows of image data. */
1180
PNG_EXPORT(void,png_read_rows,(png_structp png_ptr, png_bytepp row,
1181
    png_bytepp display_row, png_uint_32 num_rows),,55);
1182
#endif
G
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1183

1184
#ifdef PNG_SEQUENTIAL_READ_SUPPORTED
1185
/* Read a row of data. */
1186
PNG_EXPORT(void,png_read_row,(png_structp png_ptr, png_bytep row,
1187
    png_bytep display_row),,56);
1188
#endif
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1189

1190
#ifdef PNG_SEQUENTIAL_READ_SUPPORTED
1191
/* Read the whole image into memory at once. */
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1192
PNG_EXPORT(void,png_read_image,(png_structp png_ptr, png_bytepp image),,57);
1193
#endif
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1194

1195
/* Write a row of image data */
1196
PNG_EXPORT(void,png_write_row,(png_structp png_ptr, png_const_bytep row),,58);
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1197

1198
/* Write a few rows of image data: (*row) is not written; however, the type is
1199 1200 1201 1202
 * declared as writeable to maintain compatibility with previous versions of
 * libpng and to allow the 'display_row' array from read_rows to be passed
 * unchanged to write_rows.
 */
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1203 1204
PNG_EXPORT(void,png_write_rows,(png_structp png_ptr, png_bytepp row,
    png_uint_32 num_rows),,59);
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1205

1206
/* Write the image data */
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1207
PNG_EXPORT(void,png_write_image,(png_structp png_ptr, png_bytepp image),,60);
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1208

1209
/* Write the end of the PNG file. */
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1210
PNG_EXPORT(void,png_write_end,(png_structp png_ptr, png_infop info_ptr),,61);
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1211

1212
#ifdef PNG_SEQUENTIAL_READ_SUPPORTED
1213
/* Read the end of the PNG file. */
G
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1214
PNG_EXPORT(void,png_read_end,(png_structp png_ptr, png_infop info_ptr),,62);
1215
#endif
G
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1216

1217
/* Free any memory associated with the png_info_struct */
1218
PNG_EXPORT(void,png_destroy_info_struct,(png_structp png_ptr,
1219
    png_infopp info_ptr_ptr),,63);
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1220

1221
/* Free any memory associated with the png_struct and the png_info_structs */
1222
PNG_EXPORT(void,png_destroy_read_struct,(png_structpp png_ptr_ptr,
1223
    png_infopp info_ptr_ptr, png_infopp end_info_ptr_ptr),,64);
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1224

1225
/* Free any memory associated with the png_struct and the png_info_structs */
1226
PNG_EXPORT(void,png_destroy_write_struct,(png_structpp png_ptr_ptr,
1227
    png_infopp info_ptr_ptr),,65);
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1228

1229
/* Set the libpng method of handling chunk CRC errors */
G
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1230 1231
PNG_EXPORT(void,png_set_crc_action,(png_structp png_ptr, int crit_action,
    int ancil_action),,66);
A
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1232 1233

/* Values for png_set_crc_action() to say how to handle CRC errors in
A
Andreas Dilger 已提交
1234 1235 1236 1237 1238 1239 1240
 * 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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/* 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
1254 1255
 * header file (zlib.h) for an explination of the compression functions.
 */
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1257
/* Set the filtering method(s) used by libpng.  Currently, the only valid
1258 1259
 * value for "method" is 0.
 */
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PNG_EXPORT(void,png_set_filter,(png_structp png_ptr, int method, int filters),,
    67);
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/* Flags for png_set_filter() to say which filters to use.  The flags
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 * 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

1287
#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.
 */
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PNG_FP_EXPORT(void,png_set_filter_heuristics,(png_structp png_ptr,
1317 1318
    int heuristic_method, int num_weights, png_const_doublep filter_weights,
    png_const_doublep filter_costs),,68);
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PNG_FIXED_EXPORT(void,png_set_filter_heuristics_fixed,(png_structp png_ptr,
1320 1321
    int heuristic_method, int num_weights, png_const_fixed_point_p
    filter_weights, png_const_fixed_point_p filter_costs),,209);
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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.
 */
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PNG_EXPORT(void,png_set_compression_level,(png_structp png_ptr, int level),,69);
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1341
PNG_EXPORT(void,png_set_compression_mem_level,(png_structp png_ptr,
1342
    int mem_level),,70);
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1343

1344
PNG_EXPORT(void,png_set_compression_strategy,(png_structp png_ptr,
1345
    int strategy),,71);
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1346

1347
PNG_EXPORT(void,png_set_compression_window_bits,(png_structp png_ptr,
1348
    int window_bits),,72);
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PNG_EXPORT(void,png_set_compression_method,(png_structp png_ptr, int method),,
    73);
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/* These next functions are called for input/output, memory, and error
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 * 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
1358
 * different manner by calling png_set_???_fn().  See libpng-manual.txt for
A
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 * more information.
 */
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1362
#ifdef PNG_STDIO_SUPPORTED
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/* Initialize the input/output for the PNG file to the default functions. */
1364
PNG_EXPORT(void,png_init_io,(png_structp png_ptr, png_FILE_p fp),,74);
1365
#endif
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A
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/* Replace the (error and abort), and warning functions with user
A
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 * 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.
 */
1374

G
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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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/* Return the user pointer associated with the error functions */
1379
PNG_EXPORT(png_voidp,png_get_error_ptr,(png_structp png_ptr),,76);
G
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1380 1381

/* Replace the default data output functions with a user supplied one(s).
A
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 * 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).
1385 1386 1387 1388 1389
 * 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.
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 */
G
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1391 1392
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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/* Replace the default data input function with a user supplied one. */
G
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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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/* Return the user pointer associated with the I/O functions */
1399
PNG_EXPORT(png_voidp,png_get_io_ptr,(png_structp png_ptr),,79);
G
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1400

1401
PNG_EXPORT(void,png_set_read_status_fn,(png_structp png_ptr,
1402
    png_read_status_ptr read_row_fn),,80);
1403

1404
PNG_EXPORT(void,png_set_write_status_fn,(png_structp png_ptr,
1405
    png_write_status_ptr write_row_fn),,81);
1406

1407 1408
#ifdef PNG_USER_MEM_SUPPORTED
/* Replace the default memory allocation functions with user supplied one(s). */
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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);
1411
/* Return the user pointer associated with the memory functions */
1412
PNG_EXPORT(png_voidp,png_get_mem_ptr,(png_structp png_ptr),,83);
1413
#endif
1414

1415
#ifdef PNG_READ_USER_TRANSFORM_SUPPORTED
1416
PNG_EXPORT(void,png_set_read_user_transform_fn,(png_structp png_ptr,
1417
    png_user_transform_ptr read_user_transform_fn),,84);
1418 1419
#endif

1420
#ifdef PNG_WRITE_USER_TRANSFORM_SUPPORTED
1421
PNG_EXPORT(void,png_set_write_user_transform_fn,(png_structp png_ptr,
1422
    png_user_transform_ptr write_user_transform_fn),,85);
1423 1424
#endif

1425
#if defined(PNG_READ_USER_TRANSFORM_SUPPORTED) || \
1426
    defined(PNG_WRITE_USER_TRANSFORM_SUPPORTED)
1427
PNG_EXPORT(void,png_set_user_transform_info,(png_structp png_ptr,
1428 1429
    png_voidp user_transform_ptr, int user_transform_depth,
    int user_transform_channels),,86);
1430
/* Return the user pointer associated with the user transform functions */
G
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1431
PNG_EXPORT(png_voidp,png_get_user_transform_ptr,(png_structp png_ptr),,87);
1432 1433
#endif

1434
#ifdef PNG_USER_CHUNKS_SUPPORTED
1435
PNG_EXPORT(void,png_set_read_user_chunk_fn,(png_structp png_ptr,
1436
    png_voidp user_chunk_ptr, png_user_chunk_ptr read_user_chunk_fn),,88);
1437
PNG_EXPORT(png_voidp,png_get_user_chunk_ptr,(png_structp png_ptr),,89);
1438 1439
#endif

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#ifdef PNG_PROGRESSIVE_READ_SUPPORTED
A
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/* Sets the function callbacks for the push reader, and a pointer to a
 * user-defined structure available to the callback functions.
 */
1444
PNG_EXPORT(void,png_set_progressive_read_fn,(png_structp png_ptr,
1445 1446
    png_voidp progressive_ptr, png_progressive_info_ptr info_fn,
    png_progressive_row_ptr row_fn, png_progressive_end_ptr end_fn),,90);
G
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1447

1448
/* Returns the user pointer associated with the push read functions */
1449
PNG_EXPORT(png_voidp,png_get_progressive_ptr,(png_structp png_ptr),,91);
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1451
/* Function to be called when data becomes available */
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1452 1453
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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1455
/* Function that combines rows.  'new_row' is a flag that should come from the
1456
 * callback and be non-NULL if anything needs to be done; the library stores its
1457
 * own version of the new data internally and ignores the passed in value.
A
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1458
 */
1459
PNG_EXPORT(void,png_progressive_combine_row,(png_structp png_ptr,
1460
    png_bytep old_row, png_const_bytep new_row),,93);
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1461
#endif /* PNG_PROGRESSIVE_READ_SUPPORTED */
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1463 1464
PNG_EXPORT(png_voidp,png_malloc,(png_structp png_ptr, png_alloc_size_t size),
    PNG_ALLOCATED,94);
1465
/* Added at libpng version 1.4.0 */
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PNG_EXPORT(png_voidp,png_calloc,(png_structp png_ptr, png_alloc_size_t size),
    PNG_ALLOCATED,95);
G
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1468

1469
/* Added at libpng version 1.2.4 */
1470
PNG_EXPORT(png_voidp,png_malloc_warn,(png_structp png_ptr,
1471
    png_alloc_size_t size),PNG_ALLOCATED,96);
1472

1473
/* Frees a pointer allocated by png_malloc() */
1474
PNG_EXPORT(void,png_free,(png_structp png_ptr, png_voidp ptr),,97);
A
Andreas Dilger 已提交
1475

1476
/* Free data that was allocated internally */
1477
PNG_EXPORT(void,png_free_data,(png_structp png_ptr, png_infop info_ptr,
1478
    png_uint_32 free_me, int num),,98);
1479 1480
/* Reassign responsibility for freeing existing data, whether allocated
 * by libpng or by the application */
1481
PNG_EXPORT(void,png_data_freer,(png_structp png_ptr, png_infop info_ptr,
1482
    int freer, png_uint_32 mask),,99);
1483
/* Assignments for png_data_freer */
1484 1485 1486 1487
#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 */
1488 1489 1490 1491
#define PNG_FREE_HIST 0x0008
#define PNG_FREE_ICCP 0x0010
#define PNG_FREE_SPLT 0x0020
#define PNG_FREE_ROWS 0x0040
1492 1493
#define PNG_FREE_PCAL 0x0080
#define PNG_FREE_SCAL 0x0100
1494 1495
#define PNG_FREE_UNKN 0x0200
#define PNG_FREE_LIST 0x0400
1496 1497 1498
#define PNG_FREE_PLTE 0x1000
#define PNG_FREE_TRNS 0x2000
#define PNG_FREE_TEXT 0x4000
1499
#define PNG_FREE_ALL  0x7fff
1500
#define PNG_FREE_MUL  0x4220 /* PNG_FREE_SPLT|PNG_FREE_TEXT|PNG_FREE_UNKN */
1501

1502
#ifdef PNG_USER_MEM_SUPPORTED
1503
PNG_EXPORT(png_voidp,png_malloc_default,(png_structp png_ptr,
1504
    png_alloc_size_t size),PNG_ALLOCATED,100);
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1505
PNG_EXPORT(void,png_free_default,(png_structp png_ptr, png_voidp ptr),,101);
1506
#endif
1507

1508
#ifdef PNG_ERROR_TEXT_SUPPORTED
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1509
/* Fatal error in PNG image of libpng - can't continue */
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PNG_EXPORT(void,png_error,(png_structp png_ptr, png_const_charp error_message),
    PNG_NORETURN,102);
G
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1512

1513
/* The same, but the chunk name is prepended to the error string. */
1514
PNG_EXPORT(void,png_chunk_error,(png_structp png_ptr,
1515
    png_const_charp error_message),PNG_NORETURN,103);
1516

1517 1518
#else
/* Fatal error in PNG image of libpng - can't continue */
1519
PNG_EXPORT(void,png_err,(png_structp png_ptr),PNG_NORETURN,104);
1520 1521
#endif

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1522
/* Non-fatal error in libpng.  Can continue, but may have a problem. */
1523
PNG_EXPORT(void,png_warning,(png_structp png_ptr,
1524
    png_const_charp warning_message),,105);
A
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1525

1526
/* Non-fatal error in libpng, chunk name is prepended to message. */
1527
PNG_EXPORT(void,png_chunk_warning,(png_structp png_ptr,
1528
    png_const_charp warning_message),,106);
1529

1530 1531 1532
#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. */
1533
#  undef png_benign_error
1534
PNG_EXPORT(void,png_benign_error,(png_structp png_ptr,
1535
    png_const_charp warning_message),,107);
1536 1537

/* Same, chunk name is prepended to message. */
1538
#  undef png_chunk_benign_error
1539
PNG_EXPORT(void,png_chunk_benign_error,(png_structp png_ptr,
1540
    png_const_charp warning_message),,108);
1541

G
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1542
PNG_EXPORT(void,png_set_benign_errors,(png_structp png_ptr, int allowed),,109);
1543 1544 1545 1546 1547 1548 1549 1550
#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
1551 1552
#endif

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/* 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.
 */
1565
/* Returns "flag" if chunk data is valid in info_ptr. */
G
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1566 1567
PNG_EXPORT(png_uint_32,png_get_valid,(png_structp png_ptr, png_infop info_ptr,
    png_uint_32 flag),,110);
A
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1568

1569
/* Returns number of bytes needed to hold a transformed row. */
1570
PNG_EXPORT(png_size_t,png_get_rowbytes,(png_structp png_ptr,
1571
    png_infop info_ptr),,111);
A
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1572

1573
#ifdef PNG_INFO_IMAGE_SUPPORTED
1574
/* Returns row_pointers, which is an array of pointers to scanlines that was
1575 1576
 * returned from png_read_png().
 */
G
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1577 1578
PNG_EXPORT(png_bytepp,png_get_rows,(png_structp png_ptr, png_infop info_ptr),,
    112);
1579
/* Set row_pointers, which is an array of pointers to scanlines for use
1580 1581
 * by png_write_png().
 */
1582
PNG_EXPORT(void,png_set_rows,(png_structp png_ptr, png_infop info_ptr,
1583
    png_bytepp row_pointers),,113);
1584 1585
#endif

1586
/* Returns number of color channels in image. */
G
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1587 1588
PNG_EXPORT(png_byte,png_get_channels,(png_structp png_ptr, png_infop info_ptr),,
    114);
A
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1589

1590 1591
#ifdef PNG_EASY_ACCESS_SUPPORTED
/* Returns image width in pixels. */
G
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1592
PNG_EXPORT(png_uint_32,png_get_image_width,(png_structp png_ptr,
1593
    png_infop info_ptr),,115);
1594 1595

/* Returns image height in pixels. */
G
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1596
PNG_EXPORT(png_uint_32,png_get_image_height,(png_structp png_ptr,
1597
    png_infop info_ptr),,116);
1598 1599

/* Returns image bit_depth. */
G
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1600 1601
PNG_EXPORT(png_byte,png_get_bit_depth,(png_structp png_ptr, png_infop info_ptr),
    ,117);
1602 1603

/* Returns image color_type. */
G
[devel]  
Glenn Randers-Pehrson 已提交
1604
PNG_EXPORT(png_byte,png_get_color_type,(png_structp png_ptr,
1605
    png_infop info_ptr),,118);
1606 1607

/* Returns image filter_type. */
G
[devel]  
Glenn Randers-Pehrson 已提交
1608
PNG_EXPORT(png_byte,png_get_filter_type,(png_structp png_ptr,
1609
    png_infop info_ptr),,119);
1610 1611

/* Returns image interlace_type. */
G
[devel]  
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1612
PNG_EXPORT(png_byte,png_get_interlace_type,(png_structp png_ptr,
1613
    png_infop info_ptr),,120);
1614 1615

/* Returns image compression_type. */
G
[devel]  
Glenn Randers-Pehrson 已提交
1616
PNG_EXPORT(png_byte,png_get_compression_type,(png_structp png_ptr,
1617
    png_infop info_ptr),,121);
1618 1619

/* Returns image resolution in pixels per meter, from pHYs chunk data. */
G
[devel]  
Glenn Randers-Pehrson 已提交
1620
PNG_EXPORT(png_uint_32,png_get_pixels_per_meter,(png_structp png_ptr,
1621
    png_infop info_ptr),,122);
G
[devel]  
Glenn Randers-Pehrson 已提交
1622 1623 1624 1625
PNG_EXPORT(png_uint_32,png_get_x_pixels_per_meter,(png_structp png_ptr,
    png_infop info_ptr),,123);
PNG_EXPORT(png_uint_32,png_get_y_pixels_per_meter,(png_structp png_ptr,
    png_infop info_ptr),,124);
1626 1627

/* Returns pixel aspect ratio, computed from pHYs chunk data.  */
G
[devel]  
Glenn Randers-Pehrson 已提交
1628 1629 1630 1631
PNG_FP_EXPORT(float,png_get_pixel_aspect_ratio,(png_structp png_ptr,
    png_infop info_ptr),,125);
PNG_FIXED_EXPORT(png_fixed_point,png_get_pixel_aspect_ratio_fixed,
    (png_structp png_ptr, png_infop info_ptr),,210);
1632 1633

/* Returns image x, y offset in pixels or microns, from oFFs chunk data. */
G
[devel]  
Glenn Randers-Pehrson 已提交
1634 1635 1636 1637 1638 1639 1640 1641
PNG_EXPORT(png_int_32,png_get_x_offset_pixels,(png_structp png_ptr,
    png_infop info_ptr),,126);
PNG_EXPORT(png_int_32,png_get_y_offset_pixels,(png_structp png_ptr,
    png_infop info_ptr),,127);
PNG_EXPORT(png_int_32,png_get_x_offset_microns,(png_structp png_ptr,
    png_infop info_ptr),,128);
PNG_EXPORT(png_int_32, png_get_y_offset_microns,(png_structp png_ptr,
    png_infop info_ptr),,129);
1642 1643 1644

#endif /* PNG_EASY_ACCESS_SUPPORTED */

A
Andreas Dilger 已提交
1645
/* Returns pointer to signature string read from PNG header */
1646
PNG_EXPORT(png_const_bytep,png_get_signature,(png_structp png_ptr,
1647
    png_infop info_ptr),,130);
A
Andreas Dilger 已提交
1648

1649
#ifdef PNG_bKGD_SUPPORTED
G
[devel]  
Glenn Randers-Pehrson 已提交
1650 1651
PNG_EXPORT(png_uint_32,png_get_bKGD,(png_structp png_ptr, png_infop info_ptr,
    png_color_16p *background),,131);
1652
#endif
A
Andreas Dilger 已提交
1653

1654
#ifdef PNG_bKGD_SUPPORTED
G
[devel]  
Glenn Randers-Pehrson 已提交
1655
PNG_EXPORT(void,png_set_bKGD,(png_structp png_ptr, png_infop info_ptr,
1656
    png_const_color_16p background),,132);
1657
#endif
A
Andreas Dilger 已提交
1658

1659
#ifdef PNG_cHRM_SUPPORTED
G
[devel]  
Glenn Randers-Pehrson 已提交
1660 1661 1662 1663 1664 1665 1666 1667 1668 1669 1670 1671
PNG_FP_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);
#ifdef PNG_FIXED_POINT_SUPPORTED /* Otherwise not implemented */
PNG_FIXED_EXPORT(png_uint_32,png_get_cHRM_fixed,(png_structp png_ptr,
    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, png_fixed_point *int_blue_x,
    png_fixed_point *int_blue_y),,134);
#endif
1672
#endif
A
Andreas Dilger 已提交
1673

1674
#ifdef PNG_cHRM_SUPPORTED
G
[devel]  
Glenn Randers-Pehrson 已提交
1675 1676 1677 1678 1679 1680 1681 1682 1683
PNG_FP_EXPORT(void,png_set_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),,135);
PNG_FIXED_EXPORT(void,png_set_cHRM_fixed,(png_structp png_ptr,
    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, png_fixed_point int_blue_x,
    png_fixed_point int_blue_y),,136);
1684
#endif
A
Andreas Dilger 已提交
1685

1686
#ifdef PNG_gAMA_SUPPORTED
G
[devel]  
Glenn Randers-Pehrson 已提交
1687 1688 1689
PNG_FP_EXPORT(png_uint_32,png_get_gAMA,(png_structp png_ptr, png_infop info_ptr,
    double *file_gamma),,137);
PNG_FIXED_EXPORT(png_uint_32,png_get_gAMA_fixed,(png_structp png_ptr,
1690
    png_infop info_ptr, png_fixed_point *int_file_gamma),,138);
1691
#endif
G
Guy Schalnat 已提交
1692

1693
#ifdef PNG_gAMA_SUPPORTED
G
[devel]  
Glenn Randers-Pehrson 已提交
1694 1695 1696
PNG_FP_EXPORT(void,png_set_gAMA,(png_structp png_ptr, png_infop info_ptr,
    double file_gamma),,139);
PNG_FIXED_EXPORT(void,png_set_gAMA_fixed,(png_structp png_ptr,
1697
    png_infop info_ptr, png_fixed_point int_file_gamma),,140);
1698
#endif
A
Andreas Dilger 已提交
1699

1700
#ifdef PNG_hIST_SUPPORTED
G
[devel]  
Glenn Randers-Pehrson 已提交
1701 1702
PNG_EXPORT(png_uint_32,png_get_hIST,(png_structp png_ptr, png_infop info_ptr,
    png_uint_16p *hist),,141);
1703
#endif
A
Andreas Dilger 已提交
1704

1705
#ifdef PNG_hIST_SUPPORTED
G
[devel]  
Glenn Randers-Pehrson 已提交
1706
PNG_EXPORT(void,png_set_hIST,(png_structp png_ptr, png_infop info_ptr,
1707
    png_const_uint_16p hist),,142);
1708
#endif
A
Andreas Dilger 已提交
1709

G
[devel]  
Glenn Randers-Pehrson 已提交
1710 1711 1712
PNG_EXPORT(png_uint_32,png_get_IHDR,(png_structp png_ptr, png_infop info_ptr,
    png_uint_32 *width, png_uint_32 *height, int *bit_depth, int *color_type,
    int *interlace_method, int *compression_method, int *filter_method),,143);
1713

G
[devel]  
Glenn Randers-Pehrson 已提交
1714 1715 1716
PNG_EXPORT(void,png_set_IHDR,(png_structp png_ptr, png_infop info_ptr,
    png_uint_32 width, png_uint_32 height, int bit_depth, int color_type,
    int interlace_method, int compression_method, int filter_method),,144);
A
Andreas Dilger 已提交
1717

1718
#ifdef PNG_oFFs_SUPPORTED
G
[devel]  
Glenn Randers-Pehrson 已提交
1719 1720
PNG_EXPORT(png_uint_32,png_get_oFFs,(png_structp png_ptr, png_infop info_ptr,
    png_int_32 *offset_x, png_int_32 *offset_y, int *unit_type),,145);
1721
#endif
A
Andreas Dilger 已提交
1722

1723
#ifdef PNG_oFFs_SUPPORTED
G
[devel]  
Glenn Randers-Pehrson 已提交
1724 1725
PNG_EXPORT(void,png_set_oFFs,(png_structp png_ptr, png_infop info_ptr,
    png_int_32 offset_x, png_int_32 offset_y, int unit_type),,146);
1726
#endif
A
Andreas Dilger 已提交
1727

1728
#ifdef PNG_pCAL_SUPPORTED
G
[devel]  
Glenn Randers-Pehrson 已提交
1729 1730 1731
PNG_EXPORT(png_uint_32,png_get_pCAL,(png_structp png_ptr, png_infop info_ptr,
    png_charp *purpose, png_int_32 *X0, png_int_32 *X1, int *type, int *nparams,
    png_charp *units, png_charpp *params),,147);
1732
#endif
A
Andreas Dilger 已提交
1733

1734
#ifdef PNG_pCAL_SUPPORTED
G
[devel]  
Glenn Randers-Pehrson 已提交
1735
PNG_EXPORT(void,png_set_pCAL,(png_structp png_ptr, png_infop info_ptr,
1736 1737
    png_const_charp purpose, png_int_32 X0, png_int_32 X1, int type,
    int nparams, png_const_charp units, png_charpp params),,148);
1738 1739
#endif

1740
#ifdef PNG_pHYs_SUPPORTED
G
[devel]  
Glenn Randers-Pehrson 已提交
1741 1742
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);
1743
#endif
A
Andreas Dilger 已提交
1744

1745
#ifdef PNG_pHYs_SUPPORTED
G
[devel]  
Glenn Randers-Pehrson 已提交
1746 1747
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);
1748
#endif
A
Andreas Dilger 已提交
1749

G
[devel]  
Glenn Randers-Pehrson 已提交
1750 1751
PNG_EXPORT(png_uint_32,png_get_PLTE,(png_structp png_ptr, png_infop info_ptr,
    png_colorp *palette, int *num_palette),,151);
A
Andreas Dilger 已提交
1752

G
[devel]  
Glenn Randers-Pehrson 已提交
1753
PNG_EXPORT(void,png_set_PLTE,(png_structp png_ptr, png_infop info_ptr,
1754
    png_const_colorp palette, int num_palette),,152);
A
Andreas Dilger 已提交
1755

1756
#ifdef PNG_sBIT_SUPPORTED
G
[devel]  
Glenn Randers-Pehrson 已提交
1757 1758
PNG_EXPORT(png_uint_32,png_get_sBIT,(png_structp png_ptr, png_infop info_ptr,
    png_color_8p *sig_bit),,153);
1759
#endif
A
Andreas Dilger 已提交
1760

1761
#ifdef PNG_sBIT_SUPPORTED
G
[devel]  
Glenn Randers-Pehrson 已提交
1762
PNG_EXPORT(void,png_set_sBIT,(png_structp png_ptr, png_infop info_ptr,
1763
    png_const_color_8p sig_bit),,154);
1764
#endif
A
Andreas Dilger 已提交
1765

1766
#ifdef PNG_sRGB_SUPPORTED
G
[devel]  
Glenn Randers-Pehrson 已提交
1767 1768
PNG_EXPORT(png_uint_32,png_get_sRGB,(png_structp png_ptr, png_infop info_ptr,
    int *intent),,155);
1769
#endif
1770

1771
#ifdef PNG_sRGB_SUPPORTED
G
[devel]  
Glenn Randers-Pehrson 已提交
1772 1773
PNG_EXPORT(void,png_set_sRGB,(png_structp png_ptr, png_infop info_ptr,
    int intent),,156);
1774
PNG_EXPORT(void,png_set_sRGB_gAMA_and_cHRM,(png_structp png_ptr,
1775
    png_infop info_ptr, int intent),,157);
1776 1777
#endif

1778
#ifdef PNG_iCCP_SUPPORTED
G
[devel]  
Glenn Randers-Pehrson 已提交
1779 1780 1781
PNG_EXPORT(png_uint_32,png_get_iCCP,(png_structp png_ptr, png_infop info_ptr,
    png_charpp name, int *compression_type, png_bytepp profile,
    png_uint_32 *proflen),,158);
1782 1783
#endif

1784
#ifdef PNG_iCCP_SUPPORTED
G
[devel]  
Glenn Randers-Pehrson 已提交
1785
PNG_EXPORT(void,png_set_iCCP,(png_structp png_ptr, png_infop info_ptr,
1786
    png_const_charp name, int compression_type, png_const_bytep profile,
G
[devel]  
Glenn Randers-Pehrson 已提交
1787
    png_uint_32 proflen),,159);
1788 1789
#endif

1790
#ifdef PNG_sPLT_SUPPORTED
G
[devel]  
Glenn Randers-Pehrson 已提交
1791 1792
PNG_EXPORT(png_uint_32,png_get_sPLT,(png_structp png_ptr, png_infop info_ptr,
    png_sPLT_tpp entries),,160);
1793 1794
#endif

1795
#ifdef PNG_sPLT_SUPPORTED
G
[devel]  
Glenn Randers-Pehrson 已提交
1796
PNG_EXPORT(void,png_set_sPLT,(png_structp png_ptr, png_infop info_ptr,
1797
    png_const_sPLT_tp entries, int nentries),,161);
1798 1799
#endif

1800
#ifdef PNG_TEXT_SUPPORTED
1801
/* png_get_text also returns the number of text chunks in *num_text */
G
[devel]  
Glenn Randers-Pehrson 已提交
1802 1803
PNG_EXPORT(png_uint_32,png_get_text,(png_structp png_ptr, png_infop info_ptr,
    png_textp *text_ptr, int *num_text),,162);
1804
#endif
A
Andreas Dilger 已提交
1805

1806 1807 1808 1809 1810
/* 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.
1811 1812
 */

1813
#ifdef PNG_TEXT_SUPPORTED
G
[devel]  
Glenn Randers-Pehrson 已提交
1814
PNG_EXPORT(void,png_set_text,(png_structp png_ptr, png_infop info_ptr,
1815
    png_const_textp text_ptr, int num_text),,163);
1816
#endif
A
Andreas Dilger 已提交
1817

1818
#ifdef PNG_tIME_SUPPORTED
G
[devel]  
Glenn Randers-Pehrson 已提交
1819 1820
PNG_EXPORT(png_uint_32,png_get_tIME,(png_structp png_ptr, png_infop info_ptr,
    png_timep *mod_time),,164);
1821
#endif
A
Andreas Dilger 已提交
1822

1823
#ifdef PNG_tIME_SUPPORTED
G
[devel]  
Glenn Randers-Pehrson 已提交
1824
PNG_EXPORT(void,png_set_tIME,(png_structp png_ptr, png_infop info_ptr,
1825
    png_const_timep mod_time),,165);
1826
#endif
A
Andreas Dilger 已提交
1827

1828
#ifdef PNG_tRNS_SUPPORTED
G
[devel]  
Glenn Randers-Pehrson 已提交
1829 1830
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);
1831 1832
#endif

1833
#ifdef PNG_tRNS_SUPPORTED
G
[devel]  
Glenn Randers-Pehrson 已提交
1834
PNG_EXPORT(void,png_set_tRNS,(png_structp png_ptr, png_infop info_ptr,
1835 1836
    png_const_bytep trans_alpha, int num_trans,
    png_const_color_16p trans_color),,167);
1837 1838
#endif

1839
#ifdef PNG_sCAL_SUPPORTED
G
[devel]  
Glenn Randers-Pehrson 已提交
1840 1841
PNG_FP_EXPORT(png_uint_32,png_get_sCAL,(png_structp png_ptr, png_infop info_ptr,
    int *unit, double *width, double *height),,168);
1842 1843 1844 1845 1846 1847
#ifdef PNG_FLOATING_ARITHMETIC_SUPPORTED
/* NOTE: this API is currently implemented using floating point arithmetic,
 * consequently it can only be used on systems with floating point support.
 * In any case the range of values supported by png_fixed_point is small and it
 * is highly recommended that png_get_sCAL_s be used instead.
 */
G
[devel]  
Glenn Randers-Pehrson 已提交
1848 1849 1850
PNG_FIXED_EXPORT(png_uint_32,png_get_sCAL_fixed,(png_structp png_ptr,
    png_infop info_ptr, int *unit, png_fixed_point *width,
    png_fixed_point *height),,214);
1851
#endif
1852
PNG_EXPORT(png_uint_32,png_get_sCAL_s,(png_structp png_ptr,
G
[devel]  
Glenn Randers-Pehrson 已提交
1853 1854 1855 1856 1857 1858
    png_infop info_ptr, int *unit, png_charpp swidth, png_charpp sheight),,169);

PNG_FP_EXPORT(void,png_set_sCAL,(png_structp png_ptr, png_infop info_ptr,
    int unit, double width, double height),,170);
PNG_FIXED_EXPORT(void,png_set_sCAL_fixed,(png_structp png_ptr,
   png_infop info_ptr, int unit, png_fixed_point width,
1859
   png_fixed_point height),,213);
G
[devel]  
Glenn Randers-Pehrson 已提交
1860
PNG_EXPORT(void,png_set_sCAL_s,(png_structp png_ptr, png_infop info_ptr,
1861
    int unit, png_const_charp swidth, png_const_charp sheight),,171);
1862
#endif /* PNG_sCAL_SUPPORTED */
1863

1864 1865
#ifdef PNG_HANDLE_AS_UNKNOWN_SUPPORTED
/* Provide a list of chunks and how they are to be handled, if the built-in
1866 1867 1868
   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.
1869
      keep = 0: follow default behaviour
1870 1871 1872 1873
           = 1: do not keep
           = 2: keep only if safe-to-copy
           = 3: keep even if unsafe-to-copy
*/
G
[devel]  
Glenn Randers-Pehrson 已提交
1874
PNG_EXPORT(void, png_set_keep_unknown_chunks,(png_structp png_ptr, int keep,
1875
    png_const_bytep chunk_list, int num_chunks),,172);
1876
PNG_EXPORT(int,png_handle_as_unknown,(png_structp png_ptr,
G
[devel]  
Glenn Randers-Pehrson 已提交
1877
    png_const_bytep chunk_name),,173);
1878
#endif
1879
#ifdef PNG_UNKNOWN_CHUNKS_SUPPORTED
1880
PNG_EXPORT(void, png_set_unknown_chunks,(png_structp png_ptr,
1881 1882
    png_infop info_ptr, png_const_unknown_chunkp unknowns, int num_unknowns),,
    174);
G
[devel]  
Glenn Randers-Pehrson 已提交
1883 1884
PNG_EXPORT(void, png_set_unknown_chunk_location, (png_structp png_ptr,
    png_infop info_ptr, int chunk, int location),,175);
1885
PNG_EXPORT(int,png_get_unknown_chunks,(png_structp png_ptr,
1886
    png_infop info_ptr, png_unknown_chunkpp entries),,176);
1887 1888
#endif

1889
/* Png_free_data() will turn off the "valid" flag for anything it frees.
1890 1891 1892
 * 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);
 */
G
[devel]  
Glenn Randers-Pehrson 已提交
1893 1894
PNG_EXPORT(void, png_set_invalid,(png_structp png_ptr, png_infop info_ptr,
    int mask),,177);
1895

1896
#ifdef PNG_INFO_IMAGE_SUPPORTED
1897
/* The "params" pointer is currently not used and is for future expansion. */
G
[devel]  
Glenn Randers-Pehrson 已提交
1898 1899 1900 1901
PNG_EXPORT(void, png_read_png,(png_structp png_ptr, png_infop info_ptr,
    int transforms, png_voidp params),,178);
PNG_EXPORT(void, png_write_png,(png_structp png_ptr, png_infop info_ptr,
    int transforms, png_voidp params),,179);
1902 1903
#endif

1904 1905 1906 1907
PNG_EXPORT(png_const_charp,png_get_copyright,(png_structp png_ptr),,180);
PNG_EXPORT(png_const_charp,png_get_header_ver,(png_structp png_ptr),,181);
PNG_EXPORT(png_const_charp,png_get_header_version,(png_structp png_ptr),,182);
PNG_EXPORT(png_const_charp,png_get_libpng_ver,(png_structp png_ptr),,183);
1908

1909
#ifdef PNG_MNG_FEATURES_SUPPORTED
1910
PNG_EXPORT(png_uint_32,png_permit_mng_features,(png_structp png_ptr,
1911
    png_uint_32 mng_features_permitted),,184);
1912 1913
#endif

1914 1915 1916 1917 1918 1919
/* 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

1920
/* Strip the prepended error numbers ("#nnn ") from error and warning
1921 1922
 * messages before passing them to the error or warning handler.
 */
1923
#ifdef PNG_ERROR_NUMBERS_SUPPORTED
1924
PNG_EXPORT(void,png_set_strip_error_numbers,(png_structp png_ptr,
1925
    png_uint_32 strip_mode),,185);
1926
#endif
1927

1928
/* Added in libpng-1.2.6 */
1929
#ifdef PNG_SET_USER_LIMITS_SUPPORTED
1930
PNG_EXPORT(void,png_set_user_limits,(png_structp png_ptr,
1931
    png_uint_32 user_width_max, png_uint_32 user_height_max),,186);
G
[devel]  
Glenn Randers-Pehrson 已提交
1932 1933
PNG_EXPORT(png_uint_32,png_get_user_width_max,(png_structp png_ptr),,187);
PNG_EXPORT(png_uint_32,png_get_user_height_max,(png_structp png_ptr),,188);
1934
/* Added in libpng-1.4.0 */
1935
PNG_EXPORT(void,png_set_chunk_cache_max,(png_structp png_ptr,
1936
    png_uint_32 user_chunk_cache_max),,189);
G
[devel]  
Glenn Randers-Pehrson 已提交
1937
PNG_EXPORT(png_uint_32,png_get_chunk_cache_max,(png_structp png_ptr),,190);
1938
/* Added in libpng-1.4.1 */
1939
PNG_EXPORT(void,png_set_chunk_malloc_max,(png_structp png_ptr,
1940
    png_alloc_size_t user_chunk_cache_max),,191);
G
[devel]  
Glenn Randers-Pehrson 已提交
1941 1942
PNG_EXPORT(png_alloc_size_t,png_get_chunk_malloc_max,(png_structp png_ptr),,
    192);
1943 1944
#endif

G
[devel]  
Glenn Randers-Pehrson 已提交
1945
#if defined(PNG_INCH_CONVERSIONS_SUPPORTED)
1946 1947
PNG_EXPORT(png_uint_32,png_get_pixels_per_inch,(png_structp png_ptr,
    png_infop info_ptr),,193);
1948

1949 1950
PNG_EXPORT(png_uint_32,png_get_x_pixels_per_inch,(png_structp png_ptr,
    png_infop info_ptr),,194);
1951

1952 1953
PNG_EXPORT(png_uint_32,png_get_y_pixels_per_inch,(png_structp png_ptr,
    png_infop info_ptr),,195);
1954

G
[devel]  
Glenn Randers-Pehrson 已提交
1955
PNG_FP_EXPORT(float,png_get_x_offset_inches,(png_structp png_ptr,
1956
    png_infop info_ptr),,196);
G
[devel]  
Glenn Randers-Pehrson 已提交
1957 1958 1959 1960
#ifdef PNG_FIXED_POINT_SUPPORTED /* otherwise not implemented. */
PNG_FIXED_EXPORT(png_fixed_point,png_get_x_offset_inches_fixed,
    (png_structp png_ptr, png_infop info_ptr),,211);
#endif
1961

G
[devel]  
Glenn Randers-Pehrson 已提交
1962
PNG_FP_EXPORT(float,png_get_y_offset_inches,(png_structp png_ptr,
1963
    png_infop info_ptr),,197);
G
[devel]  
Glenn Randers-Pehrson 已提交
1964 1965 1966 1967
#ifdef PNG_FIXED_POINT_SUPPORTED /* otherwise not implemented. */
PNG_FIXED_EXPORT(png_fixed_point,png_get_y_offset_inches_fixed,
    (png_structp png_ptr, png_infop info_ptr),,212);
#endif
1968

1969
#  ifdef PNG_pHYs_SUPPORTED
1970
PNG_EXPORT(png_uint_32,png_get_pHYs_dpi,(png_structp png_ptr,
G
[devel]  
Glenn Randers-Pehrson 已提交
1971 1972
    png_infop info_ptr, png_uint_32 *res_x, png_uint_32 *res_y, int *unit_type),
    ,198);
1973
#  endif /* PNG_pHYs_SUPPORTED */
G
[devel]  
Glenn Randers-Pehrson 已提交
1974
#endif  /* PNG_INCH_CONVERSIONS_SUPPORTED */
1975

1976 1977
/* Added in libpng-1.4.0 */
#ifdef PNG_IO_STATE_SUPPORTED
1978
PNG_EXPORT(png_uint_32,png_get_io_state,(png_structp png_ptr),,199);
1979

1980
PNG_EXPORT(png_const_bytep,png_get_io_chunk_name,(png_structp png_ptr),,200);
1981 1982

/* The flags returned by png_get_io_state() are the following: */
1983 1984 1985 1986 1987 1988 1989 1990 1991
#  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 */
1992 1993
#endif /* ?PNG_IO_STATE_SUPPORTED */

1994
#ifdef PNG_READ_COMPOSITE_NODIV_SUPPORTED
1995 1996 1997
/* 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
1998 1999 2000 2001 2002 2003 2004 2005 2006
 * 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. :-) ]
 */

2007
 /* fg and bg should be in `gamma 1.0' space; alpha is the opacity */
2008

2009 2010 2011 2012 2013
#  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);   \
2014
       (composite) = (png_byte)((temp + (temp >> 8)) >> 8); }
2015

2016 2017 2018 2019 2020
#  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); \
2021 2022
       (composite) = (png_uint_16)((temp + (temp >> 16)) >> 16); }

2023
#else  /* Standard method using integer division */
2024

2025 2026
#  define png_composite(composite, fg, alpha, bg)                          \
     (composite) = (png_byte)(((png_uint_16)(fg) * (png_uint_16)(alpha) +  \
2027 2028
     (png_uint_16)(bg) * (png_uint_16)(255 - (png_uint_16)(alpha)) +       \
     (png_uint_16)127) / 255)
2029 2030

#  define png_composite_16(composite, fg, alpha, bg)                         \
2031
     (composite) = (png_uint_16)(((png_uint_32)(fg) * (png_uint_32)(alpha) + \
2032
     (png_uint_32)(bg)*(png_uint_32)(65535L - (png_uint_32)(alpha)) +        \
2033
     (png_uint_32)32767) / (png_uint_32)65535L)
2034 2035
#endif /* PNG_READ_COMPOSITE_NODIV_SUPPORTED */

2036 2037 2038 2039
#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.
2040
 */
2041 2042 2043 2044 2045 2046 2047 2048
#  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))))
G
[devel]  
Glenn Randers-Pehrson 已提交
2049 2050
#  define png_get_int_32(buf) \
     ((png_int_32)((*(buf) & 0x80) \
2051 2052
      ? -((png_int_32)((png_get_uint_32(buf) ^ 0xffffffff)+1)) \
      : (png_int_32)png_get_uint_32(buf)))
2053
#endif
2054 2055

#ifdef PNG_READ_INT_FUNCTIONS_SUPPORTED
2056 2057 2058
PNG_EXPORT(png_uint_32,png_get_uint_32,(png_const_bytep buf),,201);
PNG_EXPORT(png_uint_16,png_get_uint_16,(png_const_bytep buf),,202);
PNG_EXPORT(png_int_32,png_get_int_32,(png_const_bytep buf),,203);
2059 2060
#endif

2061 2062
PNG_EXPORT(png_uint_32,png_get_uint_31,(png_structp png_ptr,
    png_const_bytep buf),,204);
2063 2064
/* No png_get_int_16 -- may be added if there's a real need for it. */

2065
/* Place a 32-bit number into a buffer in PNG byte order (big-endian). */
2066
#ifdef PNG_WRITE_INT_FUNCTIONS_SUPPORTED
2067
PNG_EXPORT(void,png_save_uint_32,(png_bytep buf, png_uint_32 i),,205);
2068
#endif
2069
#ifdef PNG_SAVE_INT_32_SUPPORTED
2070
PNG_EXPORT(void,png_save_int_32,(png_bytep buf, png_int_32 i),,206);
2071
#endif
2072 2073 2074 2075 2076

/* 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.
 */
2077
#ifdef PNG_WRITE_INT_FUNCTIONS_SUPPORTED
2078
PNG_EXPORT(void,png_save_uint_16,(png_bytep buf, unsigned int i),,207);
2079
/* No png_save_int_16 -- may be added if there's a real need for it. */
2080
#endif
2081

G
[devel]  
Glenn Randers-Pehrson 已提交
2082 2083 2084 2085
/* Maintainer: Put new public prototypes here ^, in libpng.3, and project
 * defs
 */

2086 2087 2088 2089
/* The last ordinal number (this is the *last* one, the next one to
 * use is one more than this.)
 */
#ifdef PNG_EXPORT_LAST_ORDINAL
2090
  PNG_EXPORT_LAST_ORDINAL(218);
2091 2092
#endif

A
Andreas Dilger 已提交
2093 2094 2095 2096
#ifdef __cplusplus
}
#endif

2097
#endif /* PNG_VERSION_INFO_ONLY */
2098
/* Do not put anything past this line */
2099
#endif /* PNG_H */