misc/winutils/include/png.h
changeset 7889 57b117d441b9
parent 7812 00696c1450da
--- a/misc/winutils/include/png.h	Mon Oct 29 17:38:54 2012 -0400
+++ b/misc/winutils/include/png.h	Mon Oct 29 18:20:08 2012 -0400
@@ -1,2674 +1,2674 @@
-
-/* png.h - header file for PNG reference library
- *
- * libpng version 1.5.13 - September 27, 2012
- * Copyright (c) 1998-2012 Glenn Randers-Pehrson
- * (Version 0.96 Copyright (c) 1996, 1997 Andreas Dilger)
- * (Version 0.88 Copyright (c) 1995, 1996 Guy Eric Schalnat, Group 42, Inc.)
- *
- * This code is released under the libpng license (See LICENSE, below)
- *
- * Authors and maintainers:
- *   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
- *   libpng versions 0.97, January 1998, through 1.5.13 - September 27, 2012: Glenn
- *   See also "Contributing Authors", below.
- *
- * Note about libpng version numbers:
- *
- *   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:
- *
- *    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)
- *    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
- *    1.0.9                    1    10009  2.1.0.9
- *    1.0.10beta1              1    10010  2.1.0.10beta1
- *    1.0.10rc1                1    10010  2.1.0.10rc1
- *    1.0.10                   1    10010  2.1.0.10
- *    1.0.11beta1-3            1    10011  2.1.0.11beta1-3
- *    1.0.11rc1                1    10011  2.1.0.11rc1
- *    1.0.11                   1    10011  2.1.0.11
- *    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)
- *    1.2.0beta1-2             2    10200  2.1.2.0beta1-2
- *    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
- *    1.2.1beta1-4             3    10201  3.1.2.1beta1-4
- *    1.2.1rc1-2               3    10201  3.1.2.1rc1-2
- *    1.2.1                    3    10201  3.1.2.1
- *    1.2.2beta1-6            12    10202  12.so.0.1.2.2beta1-6
- *    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
- *    1.0.13                  10    10013  10.so.0.1.0.13
- *    1.2.2                   12    10202  12.so.0.1.2.2
- *    1.2.3rc1-6              12    10203  12.so.0.1.2.3rc1-6
- *    1.2.3                   12    10203  12.so.0.1.2.3
- *    1.2.4beta1-3            13    10204  12.so.0.1.2.4beta1-3
- *    1.0.14rc1               13    10014  10.so.0.1.0.14rc1
- *    1.2.4rc1                13    10204  12.so.0.1.2.4rc1
- *    1.0.14                  10    10014  10.so.0.1.0.14
- *    1.2.4                   13    10204  12.so.0.1.2.4
- *    1.2.5beta1-2            13    10205  12.so.0.1.2.5beta1-2
- *    1.0.15rc1-3             10    10015  10.so.0.1.0.15rc1-3
- *    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
- *    1.2.6beta1-4            13    10206  12.so.0.1.2.6beta1-4
- *    1.0.16                  10    10016  10.so.0.1.0.16
- *    1.2.6                   13    10206  12.so.0.1.2.6
- *    1.2.7beta1-2            13    10207  12.so.0.1.2.7beta1-2
- *    1.0.17rc1               10    10017  12.so.0.1.0.17rc1
- *    1.2.7rc1                13    10207  12.so.0.1.2.7rc1
- *    1.0.17                  10    10017  12.so.0.1.0.17
- *    1.2.7                   13    10207  12.so.0.1.2.7
- *    1.2.8beta1-5            13    10208  12.so.0.1.2.8beta1-5
- *    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
- *    1.0.18                  10    10018  12.so.0.1.0.18
- *    1.2.8                   13    10208  12.so.0.1.2.8
- *    1.2.9beta1-3            13    10209  12.so.0.1.2.9beta1-3
- *    1.2.9beta4-11           13    10209  12.so.0.9[.0]
- *    1.2.9rc1                13    10209  12.so.0.9[.0]
- *    1.2.9                   13    10209  12.so.0.9[.0]
- *    1.2.10beta1-7           13    10210  12.so.0.10[.0]
- *    1.2.10rc1-2             13    10210  12.so.0.10[.0]
- *    1.2.10                  13    10210  12.so.0.10[.0]
- *    1.4.0beta1-5            14    10400  14.so.0.0[.0]
- *    1.2.11beta1-4           13    10211  12.so.0.11[.0]
- *    1.4.0beta7-8            14    10400  14.so.0.0[.0]
- *    1.2.11                  13    10211  12.so.0.11[.0]
- *    1.2.12                  13    10212  12.so.0.12[.0]
- *    1.4.0beta9-14           14    10400  14.so.0.0[.0]
- *    1.2.13                  13    10213  12.so.0.13[.0]
- *    1.4.0beta15-36          14    10400  14.so.0.0[.0]
- *    1.4.0beta37-87          14    10400  14.so.14.0[.0]
- *    1.4.0rc01               14    10400  14.so.14.0[.0]
- *    1.4.0beta88-109         14    10400  14.so.14.0[.0]
- *    1.4.0rc02-08            14    10400  14.so.14.0[.0]
- *    1.4.0                   14    10400  14.so.14.0[.0]
- *    1.4.1beta01-03          14    10401  14.so.14.1[.0]
- *    1.4.1rc01               14    10401  14.so.14.1[.0]
- *    1.4.1beta04-12          14    10401  14.so.14.1[.0]
- *    1.4.1                   14    10401  14.so.14.1[.0]
- *    1.4.2                   14    10402  14.so.14.2[.0]
- *    1.4.3                   14    10403  14.so.14.3[.0]
- *    1.4.4                   14    10404  14.so.14.4[.0]
- *    1.5.0beta01-58          15    10500  15.so.15.0[.0]
- *    1.5.0rc01-07            15    10500  15.so.15.0[.0]
- *    1.5.0                   15    10500  15.so.15.0[.0]
- *    1.5.1beta01-11          15    10501  15.so.15.1[.0]
- *    1.5.1rc01-02            15    10501  15.so.15.1[.0]
- *    1.5.1                   15    10501  15.so.15.1[.0]
- *    1.5.2beta01-03          15    10502  15.so.15.2[.0]
- *    1.5.2rc01-03            15    10502  15.so.15.2[.0]
- *    1.5.2                   15    10502  15.so.15.2[.0]
- *    1.5.3beta01-10          15    10503  15.so.15.3[.0]
- *    1.5.3rc01-02            15    10503  15.so.15.3[.0]
- *    1.5.3beta11             15    10503  15.so.15.3[.0]
- *    1.5.3 [omitted]
- *    1.5.4beta01-08          15    10504  15.so.15.4[.0]
- *    1.5.4rc01               15    10504  15.so.15.4[.0]
- *    1.5.4                   15    10504  15.so.15.4[.0]
- *    1.5.5beta01-08          15    10505  15.so.15.5[.0]
- *    1.5.5rc01               15    10505  15.so.15.5[.0]
- *    1.5.5                   15    10505  15.so.15.5[.0]
- *    1.5.6beta01-07          15    10506  15.so.15.6[.0]
- *    1.5.6rc01-03            15    10506  15.so.15.6[.0]
- *    1.5.6                   15    10506  15.so.15.6[.0]
- *    1.5.7beta01-05          15    10507  15.so.15.7[.0]
- *    1.5.7rc01-03            15    10507  15.so.15.7[.0]
- *    1.5.7                   15    10507  15.so.15.7[.0]
- *    1.5.8beta01             15    10508  15.so.15.8[.0]
- *    1.5.8rc01               15    10508  15.so.15.8[.0]
- *    1.5.8                   15    10508  15.so.15.8[.0]
- *    1.5.9beta01-02          15    10509  15.so.15.9[.0]
- *    1.5.9rc01               15    10509  15.so.15.9[.0]
- *    1.5.9                   15    10509  15.so.15.9[.0]
- *    1.5.10beta01-05         15    10510  15.so.15.10[.0]
- *    1.5.10                  15    10510  15.so.15.10[.0]
- *    1.5.11beta01            15    10511  15.so.15.11[.0]
- *    1.5.11rc01-05           15    10511  15.so.15.11[.0]
- *    1.5.11                  15    10511  15.so.15.11[.0]
- *    1.5.12                  15    10512  15.so.15.12[.0]
- *    1.5.13beta01-02         15    10513  15.so.15.13[.0]
- *    1.5.13rc01              15    10513  15.so.15.13[.0]
- *    1.5.13                  15    10513  15.so.15.13[.0]
- *
- *   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 "rcNN".
- *
- *   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.
- *
- *   DLLNUM will change each time there are forward or backward changes
- *   in binary compatibility (e.g., when a new feature is added).
- *
- * 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/
- */
-
-/*
- * COPYRIGHT NOTICE, DISCLAIMER, and LICENSE:
- *
- * If you modify libpng you may insert additional notices immediately following
- * this sentence.
- *
- * This code is released under the libpng license.
- *
- * libpng versions 1.2.6, August 15, 2004, through 1.5.13, September 27, 2012, are
- * Copyright (c) 2004, 2006-2012 Glenn Randers-Pehrson, and are
- * distributed according to the same disclaimer and license as libpng-1.2.5
- * with the following individual added to the list of Contributing Authors:
- *
- *    Cosmin Truta
- *
- * libpng versions 1.0.7, July 1, 2000, through 1.2.5, October 3, 2002, are
- * Copyright (c) 2000-2002 Glenn Randers-Pehrson, and are
- * distributed according to the same disclaimer and license as libpng-1.0.6
- * with the following individuals added to the list of Contributing Authors:
- *
- *    Simon-Pierre Cadieux
- *    Eric S. Raymond
- *    Gilles Vollant
- *
- * 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
- * Copyright (c) 1998, 1999, 2000 Glenn Randers-Pehrson, and are
- * distributed according to the same disclaimer and license as libpng-0.96,
- * 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:
- *
- *    John Bowler
- *    Kevin Bracey
- *    Sam Bushell
- *    Magnus Holmgren
- *    Greg Roelofs
- *    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
- *    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:
- *
- *   1. The origin of this source code must not be misrepresented.
- *
- *   2. Altered versions must be plainly marked as such and must not
- *      be misrepresented as being the original source.
- *
- *   3. This Copyright notice may not be removed or altered from
- *      any source or altered source distribution.
- *
- * 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.
- */
-
-/*
- * A "png_get_copyright" function is available, for convenient use in "about"
- * boxes and the like:
- *
- *     printf("%s", png_get_copyright(NULL));
- *
- * Also, the PNG logo (in PNG format, of course) is supplied in the
- * files "pngbar.png" and "pngbar.jpg (88x31) and "pngnow.png" (98x31).
- */
-
-/*
- * 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.
- */
-
-/*
- * Y2K compliance in libpng:
- * =========================
- *
- *    September 27, 2012
- *
- *    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
- *    upward through 1.5.13 are Y2K compliant.  It is my belief that
- *    earlier versions were also Y2K compliant.
- *
- *    Libpng only has two year fields.  One is a 2-byte unsigned integer
- *    that will hold years up to 65535.  The other holds the date in text
- *    format, and will hold years up to 9999.
- *
- *    The integer is
- *        "png_uint_16 year" in png_time_struct.
- *
- *    The string is
- *        "char time_buffer[29]" in png_struct.  This will be no
- *    longer used in libpng-1.6.0 and will be removed from libpng-1.7.0.
- *
- *    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
- */
-
-#ifndef PNG_H
-#define PNG_H
-
-/* This is not the place to learn how to use libpng. The file libpng-manual.txt
- * 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.
- *
- * If you just need to read a PNG file and don't want to read the documentation
- * skip to the end of this file and read the section entitled 'simplified API'.
- */
-
-/* Version information for png.h - this should match the version in png.c */
-#define PNG_LIBPNG_VER_STRING "1.5.13"
-#define PNG_HEADER_VERSION_STRING \
-     " libpng version 1.5.13 - September 27, 2012\n"
-
-#define PNG_LIBPNG_VER_SONUM   15
-#define PNG_LIBPNG_VER_DLLNUM  15
-
-/* These should match the first 3 components of PNG_LIBPNG_VER_STRING: */
-#define PNG_LIBPNG_VER_MAJOR   1
-#define PNG_LIBPNG_VER_MINOR   5
-#define PNG_LIBPNG_VER_RELEASE 13
-
-/* This should match the numeric part of the final component of
- * PNG_LIBPNG_VER_STRING, omitting any leading zero:
- */
-
-#define PNG_LIBPNG_VER_BUILD  0
-
-/* Release Status */
-#define PNG_LIBPNG_BUILD_ALPHA    1
-#define PNG_LIBPNG_BUILD_BETA     2
-#define PNG_LIBPNG_BUILD_RC       3
-#define PNG_LIBPNG_BUILD_STABLE   4
-#define PNG_LIBPNG_BUILD_RELEASE_STATUS_MASK 7
-
-/* 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 */
-
-#define PNG_LIBPNG_BUILD_BASE_TYPE PNG_LIBPNG_BUILD_STABLE
-
-/* 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
- * version 1.0.1 it's    xxyyzz, where x=major, y=minor, z=release
- */
-#define PNG_LIBPNG_VER 10513 /* 1.5.13 */
-
-/* Library configuration: these options cannot be changed after
- * the library has been built.
- */
-#ifndef PNGLCONF_H
-    /* If pnglibconf.h is missing, you can
-     * copy scripts/pnglibconf.h.prebuilt to pnglibconf.h
-     */
-#   include "pnglibconf.h"
-#endif
-
-#ifndef PNG_VERSION_INFO_ONLY
-#  ifndef PNG_BUILDING_SYMBOL_TABLE
-  /*
-   *   Standard header files (not needed for the version info or while
-   *   building symbol table -- see scripts/pnglibconf.dfa)
-   */
-#    ifdef PNG_SETJMP_SUPPORTED
-#      include <setjmp.h>
-#    endif
-
-    /* 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
-#  endif
-
-/* Machine specific configuration. */
-#  include "pngconf.h"
-#endif
-
-/*
- * Added at libpng-1.2.8
- *
- * Ref MSDN: Private as priority over Special
- * VS_FF_PRIVATEBUILD File *was not* built using standard release
- * procedures. If this value is given, the StringFileInfo block must
- * contain a PrivateBuild string.
- *
- * 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
- * StringFileInfo block must contain a SpecialBuild string.
- */
-
-#ifdef PNG_USER_PRIVATEBUILD /* From pnglibconf.h */
-#  define PNG_LIBPNG_BUILD_TYPE \
-       (PNG_LIBPNG_BUILD_BASE_TYPE | PNG_LIBPNG_BUILD_PRIVATE)
-#else
-#  ifdef PNG_LIBPNG_SPECIALBUILD
-#    define PNG_LIBPNG_BUILD_TYPE \
-         (PNG_LIBPNG_BUILD_BASE_TYPE | PNG_LIBPNG_BUILD_SPECIAL)
-#  else
-#    define PNG_LIBPNG_BUILD_TYPE (PNG_LIBPNG_BUILD_BASE_TYPE)
-#  endif
-#endif
-
-#ifndef PNG_VERSION_INFO_ONLY
-
-/* Inhibit C++ name-mangling for libpng functions but not for system calls. */
-#ifdef __cplusplus
-extern "C" {
-#endif /* __cplusplus */
-
-/* Version information for C files, stored in png.c.  This had better match
- * the version above.
- */
-#define png_libpng_ver png_get_header_ver(NULL)
-
-/* This file is arranged in several sections:
- *
- * 1. Any configuration options that can be specified by for the application
- *    code when it is built.  (Build time configuration is in pnglibconf.h)
- * 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
- * See pnglibconf.h for build time configuration
- *
- * Run time configuration allows the application to choose between
- * implementations of certain arithmetic APIs.  The default is set
- * at build time and recorded in pnglibconf.h, but it is safe to
- * 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
- */
-
-/* This triggers a compiler error in png.c, if png.c and png.h
- * do not agree upon the version number.
- */
-typedef char* png_libpng_version_1_5_13;
-
-/* 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).
- */
-typedef struct png_color_struct
-{
-   png_byte red;
-   png_byte green;
-   png_byte blue;
-} png_color;
-typedef png_color FAR * png_colorp;
-typedef PNG_CONST png_color FAR * png_const_colorp;
-typedef png_color FAR * FAR * png_colorpp;
-
-typedef struct png_color_16_struct
-{
-   png_byte index;    /* used for palette files */
-   png_uint_16 red;   /* for use in red green blue files */
-   png_uint_16 green;
-   png_uint_16 blue;
-   png_uint_16 gray;  /* for use in grayscale files */
-} png_color_16;
-typedef png_color_16 FAR * png_color_16p;
-typedef PNG_CONST png_color_16 FAR * png_const_color_16p;
-typedef png_color_16 FAR * FAR * png_color_16pp;
-
-typedef struct png_color_8_struct
-{
-   png_byte red;   /* for use in red green blue files */
-   png_byte green;
-   png_byte blue;
-   png_byte gray;  /* for use in grayscale files */
-   png_byte alpha; /* for alpha channel files */
-} png_color_8;
-typedef png_color_8 FAR * png_color_8p;
-typedef PNG_CONST png_color_8 FAR * png_const_color_8p;
-typedef png_color_8 FAR * FAR * png_color_8pp;
-
-/*
- * The following two structures are used for the in-core representation
- * of sPLT chunks.
- */
-typedef struct png_sPLT_entry_struct
-{
-   png_uint_16 red;
-   png_uint_16 green;
-   png_uint_16 blue;
-   png_uint_16 alpha;
-   png_uint_16 frequency;
-} png_sPLT_entry;
-typedef png_sPLT_entry FAR * png_sPLT_entryp;
-typedef PNG_CONST png_sPLT_entry FAR * png_const_sPLT_entryp;
-typedef png_sPLT_entry FAR * FAR * png_sPLT_entrypp;
-
-/*  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.
- */
-
-typedef struct png_sPLT_struct
-{
-   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 */
-} png_sPLT_t;
-typedef png_sPLT_t FAR * png_sPLT_tp;
-typedef PNG_CONST png_sPLT_t FAR * png_const_sPLT_tp;
-typedef png_sPLT_t FAR * FAR * png_sPLT_tpp;
-
-#ifdef PNG_TEXT_SUPPORTED
-/* 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
- * points to a regular zero-terminated C string.  The "text" fields can be a
- * regular C string, an empty string, or a NULL pointer.
- * However, the structure returned by png_get_text() will always contain
- * the "text" field as a regular zero-terminated C string (possibly
- * empty), never a NULL pointer, so it can be safely used in printf() and
- * other string-handling functions.  Note that the "itxt_length", "lang", and
- * "lang_key" members of the structure only exist when the library is built
- * with iTXt chunk support.  Prior to libpng-1.4.0 the library was built by
- * default without iTXt support. Also note that when iTXt *is* supported,
- * the "lang" and "lang_key" fields contain NULL pointers when the
- * "compression" field contains * PNG_TEXT_COMPRESSION_NONE or
- * PNG_TEXT_COMPRESSION_zTXt. Note that the "compression value" is not the
- * same as what appears in the PNG tEXt/zTXt/iTXt chunk's "compression flag"
- * which is always 0 or 1, or its "compression method" which is always 0.
- */
-typedef struct png_text_struct
-{
-   int  compression;       /* compression value:
-                             -1: tEXt, none
-                              0: zTXt, deflate
-                              1: iTXt, none
-                              2: iTXt, deflate  */
-   png_charp key;          /* keyword, 1-79 character description of "text" */
-   png_charp text;         /* comment, may be an empty string (ie "")
-                              or a NULL pointer */
-   png_size_t text_length; /* length of the text string */
-   png_size_t itxt_length; /* length of the itxt string */
-   png_charp lang;         /* language code, 0-79 characters
-                              or a NULL pointer */
-   png_charp lang_key;     /* keyword translated UTF-8 string, 0 or more
-                              chars or a NULL pointer */
-} png_text;
-typedef png_text FAR * png_textp;
-typedef PNG_CONST png_text FAR * png_const_textp;
-typedef png_text FAR * FAR * png_textpp;
-#endif
-
-/* 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
-#define PNG_ITXT_COMPRESSION_NONE     1
-#define PNG_ITXT_COMPRESSION_zTXt     2
-#define PNG_TEXT_COMPRESSION_LAST     3  /* Not a valid value */
-
-/* png_time is a way to hold the time in an machine independent way.
- * 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
- * note - PNG has always been Year 2000 compliant!
- */
-typedef struct png_time_struct
-{
-   png_uint_16 year; /* full year, as in, 1995 */
-   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) */
-} png_time;
-typedef png_time FAR * png_timep;
-typedef PNG_CONST png_time FAR * png_const_timep;
-typedef png_time FAR * FAR * png_timepp;
-
-#if defined(PNG_UNKNOWN_CHUNKS_SUPPORTED) || \
-    defined(PNG_HANDLE_AS_UNKNOWN_SUPPORTED)
-/* 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;
-
-    /* libpng-using applications should NOT directly modify this byte. */
-    png_byte location; /* mode of operation at read time */
-}
-
-
-png_unknown_chunk;
-typedef png_unknown_chunk FAR * png_unknown_chunkp;
-typedef PNG_CONST png_unknown_chunk FAR * png_const_unknown_chunkp;
-typedef png_unknown_chunk FAR * FAR * png_unknown_chunkpp;
-#endif
-
-/* Values for the unknown chunk location byte */
-
-#define PNG_HAVE_IHDR  0x01
-#define PNG_HAVE_PLTE  0x02
-#define PNG_AFTER_IDAT 0x08
-
-/* The complete definition of png_info has, as of libpng-1.5.0,
- * been moved into a separate header file that is not accessible to
- * applications.  Read libpng-manual.txt or libpng.3 for more info.
- */
-typedef struct png_info_def png_info;
-typedef png_info FAR * png_infop;
-typedef PNG_CONST png_info FAR * png_const_infop;
-typedef png_info FAR * FAR * png_infopp;
-
-/* Maximum positive integer used in PNG is (2^31)-1 */
-#define PNG_UINT_31_MAX ((png_uint_32)0x7fffffffL)
-#define PNG_UINT_32_MAX ((png_uint_32)(-1))
-#define PNG_SIZE_MAX ((png_size_t)(-1))
-
-/* These are constants for fixed point values encoded in the
- * PNG specification manner (x100000)
- */
-#define PNG_FP_1    100000
-#define PNG_FP_HALF  50000
-#define PNG_FP_MAX  ((png_fixed_point)0x7fffffffL)
-#define PNG_FP_MIN  (-PNG_FP_MAX)
-
-/* These describe the color_type field in png_info. */
-/* color type masks */
-#define PNG_COLOR_MASK_PALETTE    1
-#define PNG_COLOR_MASK_COLOR      2
-#define PNG_COLOR_MASK_ALPHA      4
-
-/* color types.  Note that not all combinations are legal */
-#define PNG_COLOR_TYPE_GRAY 0
-#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)
-#define PNG_COLOR_TYPE_GRAY_ALPHA (PNG_COLOR_MASK_ALPHA)
-/* aliases */
-#define PNG_COLOR_TYPE_RGBA  PNG_COLOR_TYPE_RGB_ALPHA
-#define PNG_COLOR_TYPE_GA  PNG_COLOR_TYPE_GRAY_ALPHA
-
-/* This is for compression type. PNG 1.0-1.2 only define the single type. */
-#define PNG_COMPRESSION_TYPE_BASE 0 /* Deflate method 8, 32K window */
-#define PNG_COMPRESSION_TYPE_DEFAULT PNG_COMPRESSION_TYPE_BASE
-
-/* This is for filter type. PNG 1.0-1.2 only define the single type. */
-#define PNG_FILTER_TYPE_BASE      0 /* Single row per-byte filtering */
-#define PNG_INTRAPIXEL_DIFFERENCING 64 /* Used only in MNG datastreams */
-#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 */
-
-/* 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 */
-
-/* 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 */
-
-/* These are for the sRGB chunk.  These values should NOT be changed. */
-#define PNG_sRGB_INTENT_PERCEPTUAL 0
-#define PNG_sRGB_INTENT_RELATIVE   1
-#define PNG_sRGB_INTENT_SATURATION 2
-#define PNG_sRGB_INTENT_ABSOLUTE   3
-#define PNG_sRGB_INTENT_LAST       4 /* Not a valid value */
-
-/* This is for text chunks */
-#define PNG_KEYWORD_MAX_LENGTH     79
-
-/* Maximum number of entries in PLTE/sPLT/tRNS arrays */
-#define PNG_MAX_PALETTE_LENGTH    256
-
-/* 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.
- */
-#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
-#define PNG_INFO_pCAL 0x0400
-#define PNG_INFO_sRGB 0x0800   /* GR-P, 0.96a */
-#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 */
-#define PNG_INFO_IDAT 0x8000   /* ESR, 1.0.6 */
-
-/* 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.
- */
-typedef struct png_row_info_struct
-{
-   png_uint_32 width;    /* width of row */
-   png_size_t rowbytes;  /* number of bytes in row */
-   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) */
-} png_row_info;
-
-typedef png_row_info FAR * png_row_infop;
-typedef png_row_info FAR * FAR * png_row_infopp;
-
-/* The complete definition of png_struct has, as of libpng-1.5.0,
- * been moved into a separate header file that is not accessible to
- * applications.  Read libpng-manual.txt or libpng.3 for more info.
- */
-typedef struct png_struct_def png_struct;
-typedef PNG_CONST png_struct FAR * png_const_structp;
-typedef png_struct FAR * png_structp;
-
-/* These are the function types for the I/O functions and for the functions
- * that allow the user to override the default I/O functions with his or her
- * own.  The png_error_ptr type should match that of user-supplied warning
- * and error functions, while the png_rw_ptr type should match that of the
- * user read/write data functions.  Note that the 'write' function must not
- * modify the buffer it is passed. The 'read' function, on the other hand, is
- * expected to return the read data in the buffer.
- */
-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));
-
-#ifdef PNG_PROGRESSIVE_READ_SUPPORTED
-typedef PNG_CALLBACK(void, *png_progressive_info_ptr, (png_structp, png_infop));
-typedef PNG_CALLBACK(void, *png_progressive_end_ptr, (png_structp, png_infop));
-
-/* The following callback receives png_uint_32 row_number, int pass for the
- * png_bytep data of the row.  When transforming an interlaced image the
- * row number is the row number within the sub-image of the interlace pass, so
- * the value will increase to the height of the sub-image (not the full image)
- * then reset to 0 for the next pass.
- *
- * Use PNG_ROW_FROM_PASS_ROW(row, pass) and PNG_COL_FROM_PASS_COL(col, pass) to
- * find the output pixel (x,y) given an interlaced sub-image pixel
- * (row,col,pass).  (See below for these macros.)
- */
-typedef PNG_CALLBACK(void, *png_progressive_row_ptr, (png_structp, png_bytep,
-    png_uint_32, int));
-#endif
-
-#if defined(PNG_READ_USER_TRANSFORM_SUPPORTED) || \
-    defined(PNG_WRITE_USER_TRANSFORM_SUPPORTED)
-typedef PNG_CALLBACK(void, *png_user_transform_ptr, (png_structp, png_row_infop,
-    png_bytep));
-#endif
-
-#ifdef PNG_USER_CHUNKS_SUPPORTED
-typedef PNG_CALLBACK(int, *png_user_chunk_ptr, (png_structp,
-    png_unknown_chunkp));
-#endif
-#ifdef PNG_UNKNOWN_CHUNKS_SUPPORTED
-typedef PNG_CALLBACK(void, *png_unknown_chunk_ptr, (png_structp));
-#endif
-
-#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 of jmp_buf.  The
- * function is required to be PNG_NORETURN, but this is not checked.  If the
- * function does return the application will crash via an abort() or similar
- * system level call.
- *
- * If you get a warning here while building the library you may 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!
- */
-PNG_FUNCTION(void, (PNGCAPI *png_longjmp_ptr), PNGARG((jmp_buf, int)), typedef);
-#endif
-
-/* Transform masks for the high-level interface */
-#define PNG_TRANSFORM_IDENTITY       0x0000    /* read and write */
-#define PNG_TRANSFORM_STRIP_16       0x0001    /* read only */
-#define PNG_TRANSFORM_STRIP_ALPHA    0x0002    /* read only */
-#define PNG_TRANSFORM_PACKING        0x0004    /* read and write */
-#define PNG_TRANSFORM_PACKSWAP       0x0008    /* read and write */
-#define PNG_TRANSFORM_EXPAND         0x0010    /* read only */
-#define PNG_TRANSFORM_INVERT_MONO    0x0020    /* read and write */
-#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 */
-#define PNG_TRANSFORM_SWAP_ENDIAN    0x0200    /* read and write */
-#define PNG_TRANSFORM_INVERT_ALPHA   0x0400    /* read and write */
-#define PNG_TRANSFORM_STRIP_FILLER   0x0800    /* write only */
-/* Added to libpng-1.2.34 */
-#define PNG_TRANSFORM_STRIP_FILLER_BEFORE PNG_TRANSFORM_STRIP_FILLER
-#define PNG_TRANSFORM_STRIP_FILLER_AFTER 0x1000 /* write only */
-/* Added to libpng-1.4.0 */
-#define PNG_TRANSFORM_GRAY_TO_RGB   0x2000      /* read only */
-/* Added to libpng-1.5.4 */
-#define PNG_TRANSFORM_EXPAND_16     0x4000      /* read only */
-#define PNG_TRANSFORM_SCALE_16      0x8000      /* read only */
-
-/* Flags for MNG supported features */
-#define PNG_FLAG_MNG_EMPTY_PLTE     0x01
-#define PNG_FLAG_MNG_FILTER_64      0x04
-#define PNG_ALL_MNG_FEATURES        0x05
-
-/* 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));
-
-typedef png_struct FAR * FAR * png_structpp;
-
-/* Section 3: exported functions
- * Here are the function definitions most commonly used.  This is not
- * the place to find out how to use libpng.  See libpng-manual.txt for the
- * full explanation, see example.c for the summary.  This just provides
- * a simple one line description of the use of each function.
- *
- * The PNG_EXPORT() and PNG_EXPORTA() macros used below are defined in
- * pngconf.h and in the *.dfn files in the scripts directory.
- *
- *   PNG_EXPORT(ordinal, type, name, (args));
- *
- *       ordinal:    ordinal that is used while building
- *                   *.def files. The ordinal value is only
- *                   relevant when preprocessing png.h with
- *                   the *.dfn files for building symbol table
- *                   entries, and are removed by pngconf.h.
- *       type:       return type of the function
- *       name:       function name
- *       args:       function arguments, with types
- *
- * When we wish to append attributes to a function prototype we use
- * the PNG_EXPORTA() macro instead.
- *
- *   PNG_EXPORTA(ordinal, type, name, (args), attributes);
- *
- *       ordinal, type, name, and args: same as in PNG_EXPORT().
- *       attributes: function attributes
- */
-
-/* Returns the version number of the library */
-PNG_EXPORT(1, png_uint_32, png_access_version_number, (void));
-
-/* Tell lib we have already handled the first <num_bytes> magic bytes.
- * Handling more than 8 bytes from the beginning of the file is an error.
- */
-PNG_EXPORT(2, void, png_set_sig_bytes, (png_structp png_ptr, int num_bytes));
-
-/* 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).
- */
-PNG_EXPORT(3, int, png_sig_cmp, (png_const_bytep sig, png_size_t start,
-    png_size_t num_to_check));
-
-/* 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))
-
-/* Allocate and initialize png_ptr struct for reading, and any other memory. */
-PNG_EXPORTA(4, 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);
-
-/* Allocate and initialize png_ptr struct for writing, and any other memory */
-PNG_EXPORTA(5, 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);
-
-PNG_EXPORT(6, png_size_t, png_get_compression_buffer_size,
-    (png_const_structp png_ptr));
-
-PNG_EXPORT(7, void, png_set_compression_buffer_size, (png_structp png_ptr,
-    png_size_t size));
-
-/* 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.
- */
-PNG_EXPORT(8, jmp_buf*, png_set_longjmp_fn, (png_structp png_ptr,
-    png_longjmp_ptr longjmp_fn, size_t jmp_buf_size));
-#  define png_jmpbuf(png_ptr) \
-      (*png_set_longjmp_fn((png_ptr), longjmp, sizeof (jmp_buf)))
-#else
-#  define png_jmpbuf(png_ptr) \
-      (LIBPNG_WAS_COMPILED_WITH__PNG_NO_SETJMP)
-#endif
-/* 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.
- */
-PNG_EXPORTA(9, void, png_longjmp, (png_structp png_ptr, int val),
-    PNG_NORETURN);
-
-#ifdef PNG_READ_SUPPORTED
-/* Reset the compression stream */
-PNG_EXPORT(10, int, png_reset_zstream, (png_structp png_ptr));
-#endif
-
-/* New functions added in libpng-1.0.2 (not enabled by default until 1.2.0) */
-#ifdef PNG_USER_MEM_SUPPORTED
-PNG_EXPORTA(11, 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);
-PNG_EXPORTA(12, 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);
-#endif
-
-/* Write the PNG file signature. */
-PNG_EXPORT(13, void, png_write_sig, (png_structp png_ptr));
-
-/* Write a PNG chunk - size, type, (optional) data, CRC. */
-PNG_EXPORT(14, void, png_write_chunk, (png_structp png_ptr, png_const_bytep
-    chunk_name, png_const_bytep data, png_size_t length));
-
-/* Write the start of a PNG chunk - length and chunk name. */
-PNG_EXPORT(15, void, png_write_chunk_start, (png_structp png_ptr,
-    png_const_bytep chunk_name, png_uint_32 length));
-
-/* Write the data of a PNG chunk started with png_write_chunk_start(). */
-PNG_EXPORT(16, void, png_write_chunk_data, (png_structp png_ptr,
-    png_const_bytep data, png_size_t length));
-
-/* Finish a chunk started with png_write_chunk_start() (includes CRC). */
-PNG_EXPORT(17, void, png_write_chunk_end, (png_structp png_ptr));
-
-/* Allocate and initialize the info structure */
-PNG_EXPORTA(18, png_infop, png_create_info_struct, (png_structp png_ptr),
-    PNG_ALLOCATED);
-
-PNG_EXPORT(19, void, png_info_init_3, (png_infopp info_ptr,
-    png_size_t png_info_struct_size));
-
-/* Writes all the PNG information before the image. */
-PNG_EXPORT(20, void, png_write_info_before_PLTE,
-    (png_structp png_ptr, png_infop info_ptr));
-PNG_EXPORT(21, void, png_write_info,
-    (png_structp png_ptr, png_infop info_ptr));
-
-#ifdef PNG_SEQUENTIAL_READ_SUPPORTED
-/* Read the information before the actual image data. */
-PNG_EXPORT(22, void, png_read_info,
-    (png_structp png_ptr, png_infop info_ptr));
-#endif
-
-#ifdef PNG_TIME_RFC1123_SUPPORTED
-PNG_EXPORT(23, png_const_charp, png_convert_to_rfc1123,
-    (png_structp png_ptr,
-    png_const_timep ptime));
-#endif
-
-#ifdef PNG_CONVERT_tIME_SUPPORTED
-/* Convert from a struct tm to png_time */
-PNG_EXPORT(24, void, png_convert_from_struct_tm, (png_timep ptime,
-    PNG_CONST struct tm FAR * ttime));
-
-/* Convert from time_t to png_time.  Uses gmtime() */
-PNG_EXPORT(25, void, png_convert_from_time_t,
-    (png_timep ptime, time_t ttime));
-#endif /* PNG_CONVERT_tIME_SUPPORTED */
-
-#ifdef PNG_READ_EXPAND_SUPPORTED
-/* Expand data to 24-bit RGB, or 8-bit grayscale, with alpha if available. */
-PNG_EXPORT(26, void, png_set_expand, (png_structp png_ptr));
-PNG_EXPORT(27, void, png_set_expand_gray_1_2_4_to_8, (png_structp png_ptr));
-PNG_EXPORT(28, void, png_set_palette_to_rgb, (png_structp png_ptr));
-PNG_EXPORT(29, void, png_set_tRNS_to_alpha, (png_structp png_ptr));
-#endif
-
-#ifdef PNG_READ_EXPAND_16_SUPPORTED
-/* Expand to 16-bit channels, forces conversion of palette to RGB and expansion
- * of a tRNS chunk if present.
- */
-PNG_EXPORT(221, void, png_set_expand_16, (png_structp png_ptr));
-#endif
-
-#if defined(PNG_READ_BGR_SUPPORTED) || defined(PNG_WRITE_BGR_SUPPORTED)
-/* Use blue, green, red order for pixels. */
-PNG_EXPORT(30, void, png_set_bgr, (png_structp png_ptr));
-#endif
-
-#ifdef PNG_READ_GRAY_TO_RGB_SUPPORTED
-/* Expand the grayscale to 24-bit RGB if necessary. */
-PNG_EXPORT(31, void, png_set_gray_to_rgb, (png_structp png_ptr));
-#endif
-
-#ifdef PNG_READ_RGB_TO_GRAY_SUPPORTED
-/* Reduce RGB to grayscale. */
-#define PNG_ERROR_ACTION_NONE  1
-#define PNG_ERROR_ACTION_WARN  2
-#define PNG_ERROR_ACTION_ERROR 3
-#define PNG_RGB_TO_GRAY_DEFAULT (-1)/*for red/green coefficients*/
-
-PNG_FP_EXPORT(32, void, png_set_rgb_to_gray, (png_structp png_ptr,
-    int error_action, double red, double green))
-PNG_FIXED_EXPORT(33, void, png_set_rgb_to_gray_fixed, (png_structp png_ptr,
-    int error_action, png_fixed_point red, png_fixed_point green))
-
-PNG_EXPORT(34, png_byte, png_get_rgb_to_gray_status, (png_const_structp
-    png_ptr));
-#endif
-
-#ifdef PNG_BUILD_GRAYSCALE_PALETTE_SUPPORTED
-PNG_EXPORT(35, void, png_build_grayscale_palette, (int bit_depth,
-    png_colorp palette));
-#endif
-
-#ifdef PNG_READ_ALPHA_MODE_SUPPORTED
-/* How the alpha channel is interpreted - this affects how the color channels of
- * a PNG file are returned when an alpha channel, or tRNS chunk in a palette
- * file, is present.
- *
- * This has no effect on the way pixels are written into a PNG output
- * datastream. The color samples in a PNG datastream are never premultiplied
- * with the alpha samples.
- *
- * The default is to return data according to the PNG specification: the alpha
- * channel is a linear measure of the contribution of the pixel to the
- * corresponding composited pixel.  The gamma encoded color channels must be
- * scaled according to the contribution and to do this it is necessary to undo
- * the encoding, scale the color values, perform the composition and reencode
- * the values.  This is the 'PNG' mode.
- *
- * The alternative is to 'associate' the alpha with the color information by
- * storing color channel values that have been scaled by the alpha.  The
- * advantage is that the color channels can be resampled (the image can be
- * scaled) in this form.  The disadvantage is that normal practice is to store
- * linear, not (gamma) encoded, values and this requires 16-bit channels for
- * still images rather than the 8-bit channels that are just about sufficient if
- * gamma encoding is used.  In addition all non-transparent pixel values,
- * including completely opaque ones, must be gamma encoded to produce the final
- * image.  This is the 'STANDARD', 'ASSOCIATED' or 'PREMULTIPLIED' mode (the
- * latter being the two common names for associated alpha color channels.)
- *
- * Since it is not necessary to perform arithmetic on opaque color values so
- * long as they are not to be resampled and are in the final color space it is
- * possible to optimize the handling of alpha by storing the opaque pixels in
- * the PNG format (adjusted for the output color space) while storing partially
- * opaque pixels in the standard, linear, format.  The accuracy required for
- * standard alpha composition is relatively low, because the pixels are
- * isolated, therefore typically the accuracy loss in storing 8-bit linear
- * values is acceptable.  (This is not true if the alpha channel is used to
- * simulate transparency over large areas - use 16 bits or the PNG mode in
- * this case!)  This is the 'OPTIMIZED' mode.  For this mode a pixel is
- * treated as opaque only if the alpha value is equal to the maximum value.
- *
- * The final choice is to gamma encode the alpha channel as well.  This is
- * broken because, in practice, no implementation that uses this choice
- * correctly undoes the encoding before handling alpha composition.  Use this
- * choice only if other serious errors in the software or hardware you use
- * mandate it; the typical serious error is for dark halos to appear around
- * opaque areas of the composited PNG image because of arithmetic overflow.
- *
- * The API function png_set_alpha_mode specifies which of these choices to use
- * with an enumerated 'mode' value and the gamma of the required output:
- */
-#define PNG_ALPHA_PNG           0 /* according to the PNG standard */
-#define PNG_ALPHA_STANDARD      1 /* according to Porter/Duff */
-#define PNG_ALPHA_ASSOCIATED    1 /* as above; this is the normal practice */
-#define PNG_ALPHA_PREMULTIPLIED 1 /* as above */
-#define PNG_ALPHA_OPTIMIZED     2 /* 'PNG' for opaque pixels, else 'STANDARD' */
-#define PNG_ALPHA_BROKEN        3 /* the alpha channel is gamma encoded */
-
-PNG_FP_EXPORT(227, void, png_set_alpha_mode, (png_structp png_ptr, int mode,
-    double output_gamma))
-PNG_FIXED_EXPORT(228, void, png_set_alpha_mode_fixed, (png_structp png_ptr,
-    int mode, png_fixed_point output_gamma))
-#endif
-
-#if defined(PNG_READ_GAMMA_SUPPORTED) || defined(PNG_READ_ALPHA_MODE_SUPPORTED)
-/* The output_gamma value is a screen gamma in libpng terminology: it expresses
- * how to decode the output values, not how they are encoded.  The values used
- * correspond to the normal numbers used to describe the overall gamma of a
- * computer display system; for example 2.2 for an sRGB conformant system.  The
- * values are scaled by 100000 in the _fixed version of the API (so 220000 for
- * sRGB.)
- *
- * The inverse of the value is always used to provide a default for the PNG file
- * encoding if it has no gAMA chunk and if png_set_gamma() has not been called
- * to override the PNG gamma information.
- *
- * When the ALPHA_OPTIMIZED mode is selected the output gamma is used to encode
- * opaque pixels however pixels with lower alpha values are not encoded,
- * regardless of the output gamma setting.
- *
- * When the standard Porter Duff handling is requested with mode 1 the output
- * encoding is set to be linear and the output_gamma value is only relevant
- * as a default for input data that has no gamma information.  The linear output
- * encoding will be overridden if png_set_gamma() is called - the results may be
- * highly unexpected!
- *
- * The following numbers are derived from the sRGB standard and the research
- * behind it.  sRGB is defined to be approximated by a PNG gAMA chunk value of
- * 0.45455 (1/2.2) for PNG.  The value implicitly includes any viewing
- * correction required to take account of any differences in the color
- * environment of the original scene and the intended display environment; the
- * value expresses how to *decode* the image for display, not how the original
- * data was *encoded*.
- *
- * sRGB provides a peg for the PNG standard by defining a viewing environment.
- * sRGB itself, and earlier TV standards, actually use a more complex transform
- * (a linear portion then a gamma 2.4 power law) than PNG can express.  (PNG is
- * limited to simple power laws.)  By saying that an image for direct display on
- * an sRGB conformant system should be stored with a gAMA chunk value of 45455
- * (11.3.3.2 and 11.3.3.5 of the ISO PNG specification) the PNG specification
- * makes it possible to derive values for other display systems and
- * environments.
- *
- * The Mac value is deduced from the sRGB based on an assumption that the actual
- * extra viewing correction used in early Mac display systems was implemented as
- * a power 1.45 lookup table.
- *
- * Any system where a programmable lookup table is used or where the behavior of
- * the final display device characteristics can be changed requires system
- * specific code to obtain the current characteristic.  However this can be
- * difficult and most PNG gamma correction only requires an approximate value.
- *
- * By default, if png_set_alpha_mode() is not called, libpng assumes that all
- * values are unencoded, linear, values and that the output device also has a
- * linear characteristic.  This is only very rarely correct - it is invariably
- * better to call png_set_alpha_mode() with PNG_DEFAULT_sRGB than rely on the
- * default if you don't know what the right answer is!
- *
- * The special value PNG_GAMMA_MAC_18 indicates an older Mac system (pre Mac OS
- * 10.6) which used a correction table to implement a somewhat lower gamma on an
- * otherwise sRGB system.
- *
- * Both these values are reserved (not simple gamma values) in order to allow
- * more precise correction internally in the future.
- *
- * NOTE: the following values can be passed to either the fixed or floating
- * point APIs, but the floating point API will also accept floating point
- * values.
- */
-#define PNG_DEFAULT_sRGB -1       /* sRGB gamma and color space */
-#define PNG_GAMMA_MAC_18 -2       /* Old Mac '1.8' gamma and color space */
-#define PNG_GAMMA_sRGB   220000   /* Television standards--matches sRGB gamma */
-#define PNG_GAMMA_LINEAR PNG_FP_1 /* Linear */
-#endif
-
-/* The following are examples of calls to png_set_alpha_mode to achieve the
- * required overall gamma correction and, where necessary, alpha
- * premultiplication.
- *
- * png_set_alpha_mode(pp, PNG_ALPHA_PNG, PNG_DEFAULT_sRGB);
- *    This is the default libpng handling of the alpha channel - it is not
- *    pre-multiplied into the color components.  In addition the call states
- *    that the output is for a sRGB system and causes all PNG files without gAMA
- *    chunks to be assumed to be encoded using sRGB.
- *
- * png_set_alpha_mode(pp, PNG_ALPHA_PNG, PNG_GAMMA_MAC);
- *    In this case the output is assumed to be something like an sRGB conformant
- *    display preceeded by a power-law lookup table of power 1.45.  This is how
- *    early Mac systems behaved.
- *
- * png_set_alpha_mode(pp, PNG_ALPHA_STANDARD, PNG_GAMMA_LINEAR);
- *    This is the classic Jim Blinn approach and will work in academic
- *    environments where everything is done by the book.  It has the shortcoming
- *    of assuming that input PNG data with no gamma information is linear - this
- *    is unlikely to be correct unless the PNG files where generated locally.
- *    Most of the time the output precision will be so low as to show
- *    significant banding in dark areas of the image.
- *
- * png_set_expand_16(pp);
- * png_set_alpha_mode(pp, PNG_ALPHA_STANDARD, PNG_DEFAULT_sRGB);
- *    This is a somewhat more realistic Jim Blinn inspired approach.  PNG files
- *    are assumed to have the sRGB encoding if not marked with a gamma value and
- *    the output is always 16 bits per component.  This permits accurate scaling
- *    and processing of the data.  If you know that your input PNG files were
- *    generated locally you might need to replace PNG_DEFAULT_sRGB with the
- *    correct value for your system.
- *
- * png_set_alpha_mode(pp, PNG_ALPHA_OPTIMIZED, PNG_DEFAULT_sRGB);
- *    If you just need to composite the PNG image onto an existing background
- *    and if you control the code that does this you can use the optimization
- *    setting.  In this case you just copy completely opaque pixels to the
- *    output.  For pixels that are not completely transparent (you just skip
- *    those) you do the composition math using png_composite or png_composite_16
- *    below then encode the resultant 8-bit or 16-bit values to match the output
- *    encoding.
- *
- * Other cases
- *    If neither the PNG nor the standard linear encoding work for you because
- *    of the software or hardware you use then you have a big problem.  The PNG
- *    case will probably result in halos around the image.  The linear encoding
- *    will probably result in a washed out, too bright, image (it's actually too
- *    contrasty.)  Try the ALPHA_OPTIMIZED mode above - this will probably
- *    substantially reduce the halos.  Alternatively try:
- *
- * png_set_alpha_mode(pp, PNG_ALPHA_BROKEN, PNG_DEFAULT_sRGB);
- *    This option will also reduce the halos, but there will be slight dark
- *    halos round the opaque parts of the image where the background is light.
- *    In the OPTIMIZED mode the halos will be light halos where the background
- *    is dark.  Take your pick - the halos are unavoidable unless you can get
- *    your hardware/software fixed!  (The OPTIMIZED approach is slightly
- *    faster.)
- *
- * When the default gamma of PNG files doesn't match the output gamma.
- *    If you have PNG files with no gamma information png_set_alpha_mode allows
- *    you to provide a default gamma, but it also sets the ouput gamma to the
- *    matching value.  If you know your PNG files have a gamma that doesn't
- *    match the output you can take advantage of the fact that
- *    png_set_alpha_mode always sets the output gamma but only sets the PNG
- *    default if it is not already set:
- *
- * png_set_alpha_mode(pp, PNG_ALPHA_PNG, PNG_DEFAULT_sRGB);
- * png_set_alpha_mode(pp, PNG_ALPHA_PNG, PNG_GAMMA_MAC);
- *    The first call sets both the default and the output gamma values, the
- *    second call overrides the output gamma without changing the default.  This
- *    is easier than achieving the same effect with png_set_gamma.  You must use
- *    PNG_ALPHA_PNG for the first call - internal checking in png_set_alpha will
- *    fire if more than one call to png_set_alpha_mode and png_set_background is
- *    made in the same read operation, however multiple calls with PNG_ALPHA_PNG
- *    are ignored.
- */
-
-#ifdef PNG_READ_STRIP_ALPHA_SUPPORTED
-PNG_EXPORT(36, void, png_set_strip_alpha, (png_structp png_ptr));
-#endif
-
-#if defined(PNG_READ_SWAP_ALPHA_SUPPORTED) || \
-    defined(PNG_WRITE_SWAP_ALPHA_SUPPORTED)
-PNG_EXPORT(37, void, png_set_swap_alpha, (png_structp png_ptr));
-#endif
-
-#if defined(PNG_READ_INVERT_ALPHA_SUPPORTED) || \
-    defined(PNG_WRITE_INVERT_ALPHA_SUPPORTED)
-PNG_EXPORT(38, void, png_set_invert_alpha, (png_structp png_ptr));
-#endif
-
-#if defined(PNG_READ_FILLER_SUPPORTED) || defined(PNG_WRITE_FILLER_SUPPORTED)
-/* Add a filler byte to 8-bit Gray or 24-bit RGB images. */
-PNG_EXPORT(39, void, png_set_filler, (png_structp png_ptr, png_uint_32 filler,
-    int flags));
-/* The values of the PNG_FILLER_ defines should NOT be changed */
-#  define PNG_FILLER_BEFORE 0
-#  define PNG_FILLER_AFTER 1
-/* Add an alpha byte to 8-bit Gray or 24-bit RGB images. */
-PNG_EXPORT(40, void, png_set_add_alpha,
-    (png_structp png_ptr, png_uint_32 filler,
-    int flags));
-#endif /* PNG_READ_FILLER_SUPPORTED || PNG_WRITE_FILLER_SUPPORTED */
-
-#if defined(PNG_READ_SWAP_SUPPORTED) || defined(PNG_WRITE_SWAP_SUPPORTED)
-/* Swap bytes in 16-bit depth files. */
-PNG_EXPORT(41, void, png_set_swap, (png_structp png_ptr));
-#endif
-
-#if defined(PNG_READ_PACK_SUPPORTED) || defined(PNG_WRITE_PACK_SUPPORTED)
-/* Use 1 byte per pixel in 1, 2, or 4-bit depth files. */
-PNG_EXPORT(42, void, png_set_packing, (png_structp png_ptr));
-#endif
-
-#if defined(PNG_READ_PACKSWAP_SUPPORTED) || \
-    defined(PNG_WRITE_PACKSWAP_SUPPORTED)
-/* Swap packing order of pixels in bytes. */
-PNG_EXPORT(43, void, png_set_packswap, (png_structp png_ptr));
-#endif
-
-#if defined(PNG_READ_SHIFT_SUPPORTED) || defined(PNG_WRITE_SHIFT_SUPPORTED)
-/* Converts files to legal bit depths. */
-PNG_EXPORT(44, void, png_set_shift, (png_structp png_ptr, png_const_color_8p
-    true_bits));
-#endif
-
-#if defined(PNG_READ_INTERLACING_SUPPORTED) || \
-    defined(PNG_WRITE_INTERLACING_SUPPORTED)
-/* 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.
-*/
-PNG_EXPORT(45, int, png_set_interlace_handling, (png_structp png_ptr));
-#endif
-
-#if defined(PNG_READ_INVERT_SUPPORTED) || defined(PNG_WRITE_INVERT_SUPPORTED)
-/* Invert monochrome files */
-PNG_EXPORT(46, void, png_set_invert_mono, (png_structp png_ptr));
-#endif
-
-#ifdef PNG_READ_BACKGROUND_SUPPORTED
-/* Handle alpha and tRNS by replacing with a background color.  Prior to
- * libpng-1.5.4 this API must not be called before the PNG file header has been
- * read.  Doing so will result in unexpected behavior and possible warnings or
- * errors if the PNG file contains a bKGD chunk.
- */
-PNG_FP_EXPORT(47, void, png_set_background, (png_structp png_ptr,
-    png_const_color_16p background_color, int background_gamma_code,
-    int need_expand, double background_gamma))
-PNG_FIXED_EXPORT(215, void, png_set_background_fixed, (png_structp png_ptr,
-    png_const_color_16p background_color, int background_gamma_code,
-    int need_expand, png_fixed_point background_gamma))
-#endif
-#ifdef PNG_READ_BACKGROUND_SUPPORTED
-#  define PNG_BACKGROUND_GAMMA_UNKNOWN 0
-#  define PNG_BACKGROUND_GAMMA_SCREEN  1
-#  define PNG_BACKGROUND_GAMMA_FILE    2
-#  define PNG_BACKGROUND_GAMMA_UNIQUE  3
-#endif
-
-#ifdef PNG_READ_SCALE_16_TO_8_SUPPORTED
-/* Scale a 16-bit depth file down to 8-bit, accurately. */
-PNG_EXPORT(229, void, png_set_scale_16, (png_structp png_ptr));
-#endif
-
-#ifdef PNG_READ_STRIP_16_TO_8_SUPPORTED
-#define PNG_READ_16_TO_8 SUPPORTED /* Name prior to 1.5.4 */
-/* Strip the second byte of information from a 16-bit depth file. */
-PNG_EXPORT(48, void, png_set_strip_16, (png_structp png_ptr));
-#endif
-
-#ifdef PNG_READ_QUANTIZE_SUPPORTED
-/* Turn on quantizing, and reduce the palette to the number of colors
- * available.
- */
-PNG_EXPORT(49, void, png_set_quantize,
-    (png_structp png_ptr, png_colorp palette,
-    int num_palette, int maximum_colors, png_const_uint_16p histogram,
-    int full_quantize));
-#endif
-
-#ifdef PNG_READ_GAMMA_SUPPORTED
-/* 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)
-
-/* Handle gamma correction. Screen_gamma=(display_exponent).
- * NOTE: this API simply sets the screen and file gamma values. It will
- * therefore override the value for gamma in a PNG file if it is called after
- * the file header has been read - use with care  - call before reading the PNG
- * file for best results!
- *
- * These routines accept the same gamma values as png_set_alpha_mode (described
- * above).  The PNG_GAMMA_ defines and PNG_DEFAULT_sRGB can be passed to either
- * API (floating point or fixed.)  Notice, however, that the 'file_gamma' value
- * is the inverse of a 'screen gamma' value.
- */
-PNG_FP_EXPORT(50, void, png_set_gamma,
-    (png_structp png_ptr, double screen_gamma,
-    double override_file_gamma))
-PNG_FIXED_EXPORT(208, void, png_set_gamma_fixed, (png_structp png_ptr,
-    png_fixed_point screen_gamma, png_fixed_point override_file_gamma))
-#endif
-
-#ifdef PNG_WRITE_FLUSH_SUPPORTED
-/* Set how many lines between output flushes - 0 for no flushing */
-PNG_EXPORT(51, void, png_set_flush, (png_structp png_ptr, int nrows));
-/* Flush the current PNG output buffer */
-PNG_EXPORT(52, void, png_write_flush, (png_structp png_ptr));
-#endif
-
-/* Optional update palette with requested transformations */
-PNG_EXPORT(53, void, png_start_read_image, (png_structp png_ptr));
-
-/* Optional call to update the users info structure */
-PNG_EXPORT(54, void, png_read_update_info,
-    (png_structp png_ptr, png_infop info_ptr));
-
-#ifdef PNG_SEQUENTIAL_READ_SUPPORTED
-/* Read one or more rows of image data. */
-PNG_EXPORT(55, void, png_read_rows, (png_structp png_ptr, png_bytepp row,
-    png_bytepp display_row, png_uint_32 num_rows));
-#endif
-
-#ifdef PNG_SEQUENTIAL_READ_SUPPORTED
-/* Read a row of data. */
-PNG_EXPORT(56, void, png_read_row, (png_structp png_ptr, png_bytep row,
-    png_bytep display_row));
-#endif
-
-#ifdef PNG_SEQUENTIAL_READ_SUPPORTED
-/* Read the whole image into memory at once. */
-PNG_EXPORT(57, void, png_read_image, (png_structp png_ptr, png_bytepp image));
-#endif
-
-/* Write a row of image data */
-PNG_EXPORT(58, void, png_write_row,
-    (png_structp png_ptr, png_const_bytep row));
-
-/* Write a few rows of image data: (*row) is not written; however, the type
- * is 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.
- */
-PNG_EXPORT(59, void, png_write_rows, (png_structp png_ptr, png_bytepp row,
-    png_uint_32 num_rows));
-
-/* Write the image data */
-PNG_EXPORT(60, void, png_write_image,
-    (png_structp png_ptr, png_bytepp image));
-
-/* Write the end of the PNG file. */
-PNG_EXPORT(61, void, png_write_end,
-    (png_structp png_ptr, png_infop info_ptr));
-
-#ifdef PNG_SEQUENTIAL_READ_SUPPORTED
-/* Read the end of the PNG file. */
-PNG_EXPORT(62, void, png_read_end, (png_structp png_ptr, png_infop info_ptr));
-#endif
-
-/* Free any memory associated with the png_info_struct */
-PNG_EXPORT(63, void, png_destroy_info_struct, (png_structp png_ptr,
-    png_infopp info_ptr_ptr));
-
-/* Free any memory associated with the png_struct and the png_info_structs */
-PNG_EXPORT(64, void, png_destroy_read_struct, (png_structpp png_ptr_ptr,
-    png_infopp info_ptr_ptr, png_infopp end_info_ptr_ptr));
-
-/* Free any memory associated with the png_struct and the png_info_structs */
-PNG_EXPORT(65, void, png_destroy_write_struct, (png_structpp png_ptr_ptr,
-    png_infopp info_ptr_ptr));
-
-/* Set the libpng method of handling chunk CRC errors */
-PNG_EXPORT(66, void, png_set_crc_action,
-    (png_structp png_ptr, int crit_action, int ancil_action));
-
-/* Values for png_set_crc_action() say how to handle CRC errors in
- * 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
- */
-#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 */
-
-/* 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
- * header file (zlib.h) for an explination of the compression functions.
- */
-
-/* Set the filtering method(s) used by libpng.  Currently, the only valid
- * value for "method" is 0.
- */
-PNG_EXPORT(67, void, png_set_filter,
-    (png_structp png_ptr, int method, int filters));
-
-/* Flags for png_set_filter() to say which filters to use.  The flags
- * 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.
- */
-#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)
-
-/* 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
-
-#ifdef PNG_WRITE_WEIGHTED_FILTER_SUPPORTED /* EXPERIMENTAL */
-/* 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.
- */
-PNG_FP_EXPORT(68, void, png_set_filter_heuristics, (png_structp png_ptr,
-    int heuristic_method, int num_weights, png_const_doublep filter_weights,
-    png_const_doublep filter_costs))
-PNG_FIXED_EXPORT(209, void, png_set_filter_heuristics_fixed,
-    (png_structp png_ptr,
-    int heuristic_method, int num_weights, png_const_fixed_point_p
-    filter_weights, png_const_fixed_point_p filter_costs))
-#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 */
-
-#ifdef PNG_WRITE_SUPPORTED
-/* 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.
- */
-PNG_EXPORT(69, void, png_set_compression_level,
-    (png_structp png_ptr, int level));
-
-PNG_EXPORT(70, void, png_set_compression_mem_level, (png_structp png_ptr,
-    int mem_level));
-
-PNG_EXPORT(71, void, png_set_compression_strategy, (png_structp png_ptr,
-    int strategy));
-
-/* If PNG_WRITE_OPTIMIZE_CMF_SUPPORTED is defined, libpng will use a
- * smaller value of window_bits if it can do so safely.
- */
-PNG_EXPORT(72, void, png_set_compression_window_bits, (png_structp png_ptr,
-    int window_bits));
-
-PNG_EXPORT(73, void, png_set_compression_method, (png_structp png_ptr,
-    int method));
-#endif
-
-#ifdef PNG_WRITE_CUSTOMIZE_ZTXT_COMPRESSION_SUPPORTED
-/* Also set zlib parameters for compressing non-IDAT chunks */
-PNG_EXPORT(222, void, png_set_text_compression_level,
-    (png_structp png_ptr, int level));
-
-PNG_EXPORT(223, void, png_set_text_compression_mem_level, (png_structp png_ptr,
-    int mem_level));
-
-PNG_EXPORT(224, void, png_set_text_compression_strategy, (png_structp png_ptr,
-    int strategy));
-
-/* If PNG_WRITE_OPTIMIZE_CMF_SUPPORTED is defined, libpng will use a
- * smaller value of window_bits if it can do so safely.
- */
-PNG_EXPORT(225, void, png_set_text_compression_window_bits, (png_structp
-    png_ptr, int window_bits));
-
-PNG_EXPORT(226, void, png_set_text_compression_method, (png_structp png_ptr,
-    int method));
-#endif /* PNG_WRITE_CUSTOMIZE_ZTXT_COMPRESSION_SUPPORTED */
-
-/* These next functions are called for input/output, memory, and error
- * handling.  They are in the file pngrio.c, pngwio.c, and pngerror.c,
- * and call standard C I/O routines such as fread(), fwrite(), and
- * fprintf().  These functions can be made to use other I/O routines
- * at run time for those applications that need to handle I/O in a
- * different manner by calling png_set_???_fn().  See libpng-manual.txt for
- * more information.
- */
-
-#ifdef PNG_STDIO_SUPPORTED
-/* Initialize the input/output for the PNG file to the default functions. */
-PNG_EXPORT(74, void, png_init_io, (png_structp png_ptr, png_FILE_p fp));
-#endif
-
-/* Replace the (error and abort), and warning functions with user
- * 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.
- */
-
-PNG_EXPORT(75, void, png_set_error_fn,
-    (png_structp png_ptr, png_voidp error_ptr,
-    png_error_ptr error_fn, png_error_ptr warning_fn));
-
-/* Return the user pointer associated with the error functions */
-PNG_EXPORT(76, png_voidp, png_get_error_ptr, (png_const_structp png_ptr));
-
-/* Replace the default data output functions with a user supplied one(s).
- * 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).
- * 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.
- */
-PNG_EXPORT(77, 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));
-
-/* Replace the default data input function with a user supplied one. */
-PNG_EXPORT(78, void, png_set_read_fn, (png_structp png_ptr, png_voidp io_ptr,
-    png_rw_ptr read_data_fn));
-
-/* Return the user pointer associated with the I/O functions */
-PNG_EXPORT(79, png_voidp, png_get_io_ptr, (png_structp png_ptr));
-
-PNG_EXPORT(80, void, png_set_read_status_fn, (png_structp png_ptr,
-    png_read_status_ptr read_row_fn));
-
-PNG_EXPORT(81, void, png_set_write_status_fn, (png_structp png_ptr,
-    png_write_status_ptr write_row_fn));
-
-#ifdef PNG_USER_MEM_SUPPORTED
-/* Replace the default memory allocation functions with user supplied one(s). */
-PNG_EXPORT(82, void, png_set_mem_fn, (png_structp png_ptr, png_voidp mem_ptr,
-    png_malloc_ptr malloc_fn, png_free_ptr free_fn));
-/* Return the user pointer associated with the memory functions */
-PNG_EXPORT(83, png_voidp, png_get_mem_ptr, (png_const_structp png_ptr));
-#endif
-
-#ifdef PNG_READ_USER_TRANSFORM_SUPPORTED
-PNG_EXPORT(84, void, png_set_read_user_transform_fn, (png_structp png_ptr,
-    png_user_transform_ptr read_user_transform_fn));
-#endif
-
-#ifdef PNG_WRITE_USER_TRANSFORM_SUPPORTED
-PNG_EXPORT(85, void, png_set_write_user_transform_fn, (png_structp png_ptr,
-    png_user_transform_ptr write_user_transform_fn));
-#endif
-
-#ifdef PNG_USER_TRANSFORM_PTR_SUPPORTED
-PNG_EXPORT(86, void, png_set_user_transform_info, (png_structp png_ptr,
-    png_voidp user_transform_ptr, int user_transform_depth,
-    int user_transform_channels));
-/* Return the user pointer associated with the user transform functions */
-PNG_EXPORT(87, png_voidp, png_get_user_transform_ptr,
-    (png_const_structp png_ptr));
-#endif
-
-#ifdef PNG_USER_TRANSFORM_INFO_SUPPORTED
-/* Return information about the row currently being processed.  Note that these
- * APIs do not fail but will return unexpected results if called outside a user
- * transform callback.  Also note that when transforming an interlaced image the
- * row number is the row number within the sub-image of the interlace pass, so
- * the value will increase to the height of the sub-image (not the full image)
- * then reset to 0 for the next pass.
- *
- * Use PNG_ROW_FROM_PASS_ROW(row, pass) and PNG_COL_FROM_PASS_COL(col, pass) to
- * find the output pixel (x,y) given an interlaced sub-image pixel
- * (row,col,pass).  (See below for these macros.)
- */
-PNG_EXPORT(217, png_uint_32, png_get_current_row_number, (png_const_structp));
-PNG_EXPORT(218, png_byte, png_get_current_pass_number, (png_const_structp));
-#endif
-
-#ifdef PNG_USER_CHUNKS_SUPPORTED
-PNG_EXPORT(88, void, png_set_read_user_chunk_fn, (png_structp png_ptr,
-    png_voidp user_chunk_ptr, png_user_chunk_ptr read_user_chunk_fn));
-PNG_EXPORT(89, png_voidp, png_get_user_chunk_ptr, (png_const_structp png_ptr));
-#endif
-
-#ifdef PNG_PROGRESSIVE_READ_SUPPORTED
-/* Sets the function callbacks for the push reader, and a pointer to a
- * user-defined structure available to the callback functions.
- */
-PNG_EXPORT(90, void, png_set_progressive_read_fn, (png_structp png_ptr,
-    png_voidp progressive_ptr, png_progressive_info_ptr info_fn,
-    png_progressive_row_ptr row_fn, png_progressive_end_ptr end_fn));
-
-/* Returns the user pointer associated with the push read functions */
-PNG_EXPORT(91, png_voidp, png_get_progressive_ptr, (png_const_structp png_ptr));
-
-/* Function to be called when data becomes available */
-PNG_EXPORT(92, void, png_process_data,
-    (png_structp png_ptr, png_infop info_ptr,
-    png_bytep buffer, png_size_t buffer_size));
-
-/* A function which may be called *only* within png_process_data to stop the
- * processing of any more data.  The function returns the number of bytes
- * remaining, excluding any that libpng has cached internally.  A subsequent
- * call to png_process_data must supply these bytes again.  If the argument
- * 'save' is set to true the routine will first save all the pending data and
- * will always return 0.
- */
-PNG_EXPORT(219, png_size_t, png_process_data_pause, (png_structp, int save));
-
-/* A function which may be called *only* outside (after) a call to
- * png_process_data.  It returns the number of bytes of data to skip in the
- * input.  Normally it will return 0, but if it returns a non-zero value the
- * application must skip than number of bytes of input data and pass the
- * following data to the next call to png_process_data.
- */
-PNG_EXPORT(220, png_uint_32, png_process_data_skip, (png_structp));
-
-#ifdef PNG_READ_INTERLACING_SUPPORTED
-/* Function that combines rows.  'new_row' is a flag that should come from
- * the callback and be non-NULL if anything needs to be done; the library
- * stores its own version of the new data internally and ignores the passed
- * in value.
- */
-PNG_EXPORT(93, void, png_progressive_combine_row, (png_structp png_ptr,
-    png_bytep old_row, png_const_bytep new_row));
-#endif /* PNG_READ_INTERLACING_SUPPORTED */
-#endif /* PNG_PROGRESSIVE_READ_SUPPORTED */
-
-PNG_EXPORTA(94, png_voidp, png_malloc,
-    (png_structp png_ptr, png_alloc_size_t size),
-    PNG_ALLOCATED);
-/* Added at libpng version 1.4.0 */
-PNG_EXPORTA(95, png_voidp, png_calloc,
-    (png_structp png_ptr, png_alloc_size_t size),
-    PNG_ALLOCATED);
-
-/* Added at libpng version 1.2.4 */
-PNG_EXPORTA(96, png_voidp, png_malloc_warn, (png_structp png_ptr,
-    png_alloc_size_t size), PNG_ALLOCATED);
-
-/* Frees a pointer allocated by png_malloc() */
-PNG_EXPORT(97, void, png_free, (png_structp png_ptr, png_voidp ptr));
-
-/* Free data that was allocated internally */
-PNG_EXPORT(98, void, png_free_data,
-    (png_structp png_ptr, png_infop info_ptr, png_uint_32 free_me, int num));
-
-/* Reassign responsibility for freeing existing data, whether allocated
- * by libpng or by the application */
-PNG_EXPORT(99, void, png_data_freer,
-    (png_structp png_ptr, png_infop info_ptr, int freer, png_uint_32 mask));
-
-/* Assignments for png_data_freer */
-#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 */
-#define PNG_FREE_HIST 0x0008
-#define PNG_FREE_ICCP 0x0010
-#define PNG_FREE_SPLT 0x0020
-#define PNG_FREE_ROWS 0x0040
-#define PNG_FREE_PCAL 0x0080
-#define PNG_FREE_SCAL 0x0100
-#define PNG_FREE_UNKN 0x0200
-#define PNG_FREE_LIST 0x0400
-#define PNG_FREE_PLTE 0x1000
-#define PNG_FREE_TRNS 0x2000
-#define PNG_FREE_TEXT 0x4000
-#define PNG_FREE_ALL  0x7fff
-#define PNG_FREE_MUL  0x4220 /* PNG_FREE_SPLT|PNG_FREE_TEXT|PNG_FREE_UNKN */
-
-#ifdef PNG_USER_MEM_SUPPORTED
-PNG_EXPORTA(100, png_voidp, png_malloc_default, (png_structp png_ptr,
-    png_alloc_size_t size), PNG_ALLOCATED);
-PNG_EXPORT(101, void, png_free_default, (png_structp png_ptr, png_voidp ptr));
-#endif
-
-#ifdef PNG_ERROR_TEXT_SUPPORTED
-/* Fatal error in PNG image of libpng - can't continue */
-PNG_EXPORTA(102, void, png_error,
-    (png_structp png_ptr, png_const_charp error_message),
-    PNG_NORETURN);
-
-/* The same, but the chunk name is prepended to the error string. */
-PNG_EXPORTA(103, void, png_chunk_error, (png_structp png_ptr,
-    png_const_charp error_message), PNG_NORETURN);
-
-#else
-/* Fatal error in PNG image of libpng - can't continue */
-PNG_EXPORTA(104, void, png_err, (png_structp png_ptr), PNG_NORETURN);
-#endif
-
-#ifdef PNG_WARNINGS_SUPPORTED
-/* Non-fatal error in libpng.  Can continue, but may have a problem. */
-PNG_EXPORT(105, void, png_warning, (png_structp png_ptr,
-    png_const_charp warning_message));
-
-/* Non-fatal error in libpng, chunk name is prepended to message. */
-PNG_EXPORT(106, void, png_chunk_warning, (png_structp png_ptr,
-    png_const_charp warning_message));
-#endif
-
-#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. */
-#  undef png_benign_error
-PNG_EXPORT(107, void, png_benign_error, (png_structp png_ptr,
-    png_const_charp warning_message));
-
-/* Same, chunk name is prepended to message. */
-#  undef png_chunk_benign_error
-PNG_EXPORT(108, void, png_chunk_benign_error, (png_structp png_ptr,
-    png_const_charp warning_message));
-
-PNG_EXPORT(109, void, png_set_benign_errors,
-    (png_structp png_ptr, int allowed));
-#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
-#endif
-
-/* 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.
- */
-/* Returns "flag" if chunk data is valid in info_ptr. */
-PNG_EXPORT(110, png_uint_32, png_get_valid,
-    (png_const_structp png_ptr, png_const_infop info_ptr,
-    png_uint_32 flag));
-
-/* Returns number of bytes needed to hold a transformed row. */
-PNG_EXPORT(111, png_size_t, png_get_rowbytes, (png_const_structp png_ptr,
-    png_const_infop info_ptr));
-
-#ifdef PNG_INFO_IMAGE_SUPPORTED
-/* Returns row_pointers, which is an array of pointers to scanlines that was
- * returned from png_read_png().
- */
-PNG_EXPORT(112, png_bytepp, png_get_rows,
-    (png_const_structp png_ptr, png_const_infop info_ptr));
-/* Set row_pointers, which is an array of pointers to scanlines for use
- * by png_write_png().
- */
-PNG_EXPORT(113, void, png_set_rows, (png_structp png_ptr,
-    png_infop info_ptr, png_bytepp row_pointers));
-#endif
-
-/* Returns number of color channels in image. */
-PNG_EXPORT(114, png_byte, png_get_channels,
-    (png_const_structp png_ptr, png_const_infop info_ptr));
-
-#ifdef PNG_EASY_ACCESS_SUPPORTED
-/* Returns image width in pixels. */
-PNG_EXPORT(115, png_uint_32, png_get_image_width, (png_const_structp png_ptr,
-    png_const_infop info_ptr));
-
-/* Returns image height in pixels. */
-PNG_EXPORT(116, png_uint_32, png_get_image_height, (png_const_structp png_ptr,
-    png_const_infop info_ptr));
-
-/* Returns image bit_depth. */
-PNG_EXPORT(117, png_byte, png_get_bit_depth,
-    (png_const_structp png_ptr, png_const_infop info_ptr));
-
-/* Returns image color_type. */
-PNG_EXPORT(118, png_byte, png_get_color_type, (png_const_structp png_ptr,
-    png_const_infop info_ptr));
-
-/* Returns image filter_type. */
-PNG_EXPORT(119, png_byte, png_get_filter_type, (png_const_structp png_ptr,
-    png_const_infop info_ptr));
-
-/* Returns image interlace_type. */
-PNG_EXPORT(120, png_byte, png_get_interlace_type, (png_const_structp png_ptr,
-    png_const_infop info_ptr));
-
-/* Returns image compression_type. */
-PNG_EXPORT(121, png_byte, png_get_compression_type, (png_const_structp png_ptr,
-    png_const_infop info_ptr));
-
-/* Returns image resolution in pixels per meter, from pHYs chunk data. */
-PNG_EXPORT(122, png_uint_32, png_get_pixels_per_meter,
-    (png_const_structp png_ptr, png_const_infop info_ptr));
-PNG_EXPORT(123, png_uint_32, png_get_x_pixels_per_meter,
-    (png_const_structp png_ptr, png_const_infop info_ptr));
-PNG_EXPORT(124, png_uint_32, png_get_y_pixels_per_meter,
-    (png_const_structp png_ptr, png_const_infop info_ptr));
-
-/* Returns pixel aspect ratio, computed from pHYs chunk data.  */
-PNG_FP_EXPORT(125, float, png_get_pixel_aspect_ratio,
-    (png_const_structp png_ptr, png_const_infop info_ptr))
-PNG_FIXED_EXPORT(210, png_fixed_point, png_get_pixel_aspect_ratio_fixed,
-    (png_const_structp png_ptr, png_const_infop info_ptr))
-
-/* Returns image x, y offset in pixels or microns, from oFFs chunk data. */
-PNG_EXPORT(126, png_int_32, png_get_x_offset_pixels,
-    (png_const_structp png_ptr, png_const_infop info_ptr));
-PNG_EXPORT(127, png_int_32, png_get_y_offset_pixels,
-    (png_const_structp png_ptr, png_const_infop info_ptr));
-PNG_EXPORT(128, png_int_32, png_get_x_offset_microns,
-    (png_const_structp png_ptr, png_const_infop info_ptr));
-PNG_EXPORT(129, png_int_32, png_get_y_offset_microns,
-    (png_const_structp png_ptr, png_const_infop info_ptr));
-
-#endif /* PNG_EASY_ACCESS_SUPPORTED */
-
-/* Returns pointer to signature string read from PNG header */
-PNG_EXPORT(130, png_const_bytep, png_get_signature,
-    (png_const_structp png_ptr, png_infop info_ptr));
-
-#ifdef PNG_bKGD_SUPPORTED
-PNG_EXPORT(131, png_uint_32, png_get_bKGD,
-    (png_const_structp png_ptr, png_infop info_ptr,
-    png_color_16p *background));
-#endif
-
-#ifdef PNG_bKGD_SUPPORTED
-PNG_EXPORT(132, void, png_set_bKGD, (png_structp png_ptr, png_infop info_ptr,
-    png_const_color_16p background));
-#endif
-
-#ifdef PNG_cHRM_SUPPORTED
-PNG_FP_EXPORT(133, png_uint_32, png_get_cHRM, (png_const_structp png_ptr,
-   png_const_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))
-PNG_FP_EXPORT(230, png_uint_32, png_get_cHRM_XYZ, (png_structp png_ptr,
-    png_const_infop info_ptr, double *red_X, double *red_Y, double *red_Z,
-    double *green_X, double *green_Y, double *green_Z, double *blue_X,
-    double *blue_Y, double *blue_Z))
-#ifdef PNG_FIXED_POINT_SUPPORTED /* Otherwise not implemented */
-PNG_FIXED_EXPORT(134, png_uint_32, png_get_cHRM_fixed,
-    (png_const_structp png_ptr,
-    png_const_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))
-#endif
-PNG_FIXED_EXPORT(231, png_uint_32, png_get_cHRM_XYZ_fixed,
-    (png_structp png_ptr, png_const_infop info_ptr,
-    png_fixed_point *int_red_X, png_fixed_point *int_red_Y,
-    png_fixed_point *int_red_Z, png_fixed_point *int_green_X,
-    png_fixed_point *int_green_Y, png_fixed_point *int_green_Z,
-    png_fixed_point *int_blue_X, png_fixed_point *int_blue_Y,
-    png_fixed_point *int_blue_Z))
-#endif
-
-#ifdef PNG_cHRM_SUPPORTED
-PNG_FP_EXPORT(135, 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))
-PNG_FP_EXPORT(232, void, png_set_cHRM_XYZ, (png_structp png_ptr,
-    png_infop info_ptr, double red_X, double red_Y, double red_Z,
-    double green_X, double green_Y, double green_Z, double blue_X,
-    double blue_Y, double blue_Z))
-PNG_FIXED_EXPORT(136, 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))
-PNG_FIXED_EXPORT(233, void, png_set_cHRM_XYZ_fixed, (png_structp png_ptr,
-    png_infop info_ptr, png_fixed_point int_red_X, png_fixed_point int_red_Y,
-    png_fixed_point int_red_Z, png_fixed_point int_green_X,
-    png_fixed_point int_green_Y, png_fixed_point int_green_Z,
-    png_fixed_point int_blue_X, png_fixed_point int_blue_Y,
-    png_fixed_point int_blue_Z))
-#endif
-
-#ifdef PNG_gAMA_SUPPORTED
-PNG_FP_EXPORT(137, png_uint_32, png_get_gAMA,
-    (png_const_structp png_ptr, png_const_infop info_ptr,
-    double *file_gamma))
-PNG_FIXED_EXPORT(138, png_uint_32, png_get_gAMA_fixed,
-    (png_const_structp png_ptr, png_const_infop info_ptr,
-    png_fixed_point *int_file_gamma))
-#endif
-
-#ifdef PNG_gAMA_SUPPORTED
-PNG_FP_EXPORT(139, void, png_set_gAMA, (png_structp png_ptr,
-    png_infop info_ptr, double file_gamma))
-PNG_FIXED_EXPORT(140, void, png_set_gAMA_fixed, (png_structp png_ptr,
-    png_infop info_ptr, png_fixed_point int_file_gamma))
-#endif
-
-#ifdef PNG_hIST_SUPPORTED
-PNG_EXPORT(141, png_uint_32, png_get_hIST,
-    (png_const_structp png_ptr, png_const_infop info_ptr,
-    png_uint_16p *hist));
-#endif
-
-#ifdef PNG_hIST_SUPPORTED
-PNG_EXPORT(142, void, png_set_hIST, (png_structp png_ptr,
-    png_infop info_ptr, png_const_uint_16p hist));
-#endif
-
-PNG_EXPORT(143, 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));
-
-PNG_EXPORT(144, 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));
-
-#ifdef PNG_oFFs_SUPPORTED
-PNG_EXPORT(145, png_uint_32, png_get_oFFs,
-    (png_const_structp png_ptr, png_const_infop info_ptr,
-    png_int_32 *offset_x, png_int_32 *offset_y, int *unit_type));
-#endif
-
-#ifdef PNG_oFFs_SUPPORTED
-PNG_EXPORT(146, 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));
-#endif
-
-#ifdef PNG_pCAL_SUPPORTED
-PNG_EXPORT(147, png_uint_32, png_get_pCAL,
-    (png_const_structp png_ptr, png_const_infop info_ptr,
-    png_charp *purpose, png_int_32 *X0, png_int_32 *X1, int *type,
-    int *nparams,
-    png_charp *units, png_charpp *params));
-#endif
-
-#ifdef PNG_pCAL_SUPPORTED
-PNG_EXPORT(148, void, png_set_pCAL, (png_structp png_ptr,
-    png_infop info_ptr,
-    png_const_charp purpose, png_int_32 X0, png_int_32 X1, int type,
-    int nparams, png_const_charp units, png_charpp params));
-#endif
-
-#ifdef PNG_pHYs_SUPPORTED
-PNG_EXPORT(149, png_uint_32, png_get_pHYs,
-    (png_const_structp png_ptr, png_const_infop info_ptr,
-    png_uint_32 *res_x, png_uint_32 *res_y, int *unit_type));
-#endif
-
-#ifdef PNG_pHYs_SUPPORTED
-PNG_EXPORT(150, 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));
-#endif
-
-PNG_EXPORT(151, png_uint_32, png_get_PLTE,
-    (png_const_structp png_ptr, png_const_infop info_ptr,
-    png_colorp *palette, int *num_palette));
-
-PNG_EXPORT(152, void, png_set_PLTE,
-    (png_structp png_ptr, png_infop info_ptr,
-    png_const_colorp palette, int num_palette));
-
-#ifdef PNG_sBIT_SUPPORTED
-PNG_EXPORT(153, png_uint_32, png_get_sBIT,
-    (png_const_structp png_ptr, png_infop info_ptr,
-    png_color_8p *sig_bit));
-#endif
-
-#ifdef PNG_sBIT_SUPPORTED
-PNG_EXPORT(154, void, png_set_sBIT,
-    (png_structp png_ptr, png_infop info_ptr, png_const_color_8p sig_bit));
-#endif
-
-#ifdef PNG_sRGB_SUPPORTED
-PNG_EXPORT(155, png_uint_32, png_get_sRGB, (png_const_structp png_ptr,
-    png_const_infop info_ptr, int *file_srgb_intent));
-#endif
-
-#ifdef PNG_sRGB_SUPPORTED
-PNG_EXPORT(156, void, png_set_sRGB,
-    (png_structp png_ptr, png_infop info_ptr, int srgb_intent));
-PNG_EXPORT(157, void, png_set_sRGB_gAMA_and_cHRM, (png_structp png_ptr,
-    png_infop info_ptr, int srgb_intent));
-#endif
-
-#ifdef PNG_iCCP_SUPPORTED
-PNG_EXPORT(158, png_uint_32, png_get_iCCP,
-    (png_const_structp png_ptr, png_const_infop info_ptr,
-    png_charpp name, int *compression_type, png_bytepp profile,
-    png_uint_32 *proflen));
-#endif
-
-#ifdef PNG_iCCP_SUPPORTED
-PNG_EXPORT(159, void, png_set_iCCP,
-    (png_structp png_ptr, png_infop info_ptr,
-    png_const_charp name, int compression_type, png_const_bytep profile,
-    png_uint_32 proflen));
-#endif
-
-#ifdef PNG_sPLT_SUPPORTED
-PNG_EXPORT(160, png_uint_32, png_get_sPLT,
-    (png_const_structp png_ptr, png_const_infop info_ptr,
-    png_sPLT_tpp entries));
-#endif
-
-#ifdef PNG_sPLT_SUPPORTED
-PNG_EXPORT(161, void, png_set_sPLT,
-    (png_structp png_ptr, png_infop info_ptr,
-    png_const_sPLT_tp entries, int nentries));
-#endif
-
-#ifdef PNG_TEXT_SUPPORTED
-/* png_get_text also returns the number of text chunks in *num_text */
-PNG_EXPORT(162, png_uint_32, png_get_text,
-    (png_const_structp png_ptr, png_const_infop info_ptr,
-    png_textp *text_ptr, int *num_text));
-#endif
-
-/* 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.
- */
-
-#ifdef PNG_TEXT_SUPPORTED
-PNG_EXPORT(163, void, png_set_text,
-    (png_structp png_ptr, png_infop info_ptr,
-    png_const_textp text_ptr, int num_text));
-#endif
-
-#ifdef PNG_tIME_SUPPORTED
-PNG_EXPORT(164, png_uint_32, png_get_tIME,
-    (png_const_structp png_ptr, png_infop info_ptr, png_timep *mod_time));
-#endif
-
-#ifdef PNG_tIME_SUPPORTED
-PNG_EXPORT(165, void, png_set_tIME,
-    (png_structp png_ptr, png_infop info_ptr, png_const_timep mod_time));
-#endif
-
-#ifdef PNG_tRNS_SUPPORTED
-PNG_EXPORT(166, png_uint_32, png_get_tRNS,
-    (png_const_structp png_ptr, png_infop info_ptr,
-    png_bytep *trans_alpha, int *num_trans, png_color_16p *trans_color));
-#endif
-
-#ifdef PNG_tRNS_SUPPORTED
-PNG_EXPORT(167, void, png_set_tRNS,
-    (png_structp png_ptr, png_infop info_ptr,
-    png_const_bytep trans_alpha, int num_trans,
-    png_const_color_16p trans_color));
-#endif
-
-#ifdef PNG_sCAL_SUPPORTED
-PNG_FP_EXPORT(168, png_uint_32, png_get_sCAL,
-    (png_const_structp png_ptr, png_const_infop info_ptr,
-    int *unit, double *width, double *height))
-#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.
- */
-PNG_FIXED_EXPORT(214, png_uint_32, png_get_sCAL_fixed,
-    (png_structp png_ptr, png_const_infop info_ptr, int *unit,
-    png_fixed_point *width,
-    png_fixed_point *height))
-#endif
-PNG_EXPORT(169, png_uint_32, png_get_sCAL_s,
-    (png_const_structp png_ptr, png_const_infop info_ptr,
-    int *unit, png_charpp swidth, png_charpp sheight));
-
-PNG_FP_EXPORT(170, void, png_set_sCAL,
-    (png_structp png_ptr, png_infop info_ptr,
-    int unit, double width, double height))
-PNG_FIXED_EXPORT(213, void, png_set_sCAL_fixed, (png_structp png_ptr,
-   png_infop info_ptr, int unit, png_fixed_point width,
-   png_fixed_point height))
-PNG_EXPORT(171, void, png_set_sCAL_s,
-    (png_structp png_ptr, png_infop info_ptr,
-    int unit, png_const_charp swidth, png_const_charp sheight));
-#endif /* PNG_sCAL_SUPPORTED */
-
-#ifdef PNG_HANDLE_AS_UNKNOWN_SUPPORTED
-/* Provide a list of chunks and how they are to be handled, if the built-in
-   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.  Because this turns off the default handling for chunks
-   that would otherwise be recognized the behavior of libpng transformations may
-   well become incorrect!
-      keep = 0: PNG_HANDLE_CHUNK_AS_DEFAULT: follow default behavior
-           = 1: PNG_HANDLE_CHUNK_NEVER:      do not keep
-           = 2: PNG_HANDLE_CHUNK_IF_SAFE:    keep only if safe-to-copy
-           = 3: PNG_HANDLE_CHUNK_ALWAYS:     keep even if unsafe-to-copy
-*/
-PNG_EXPORT(172, void, png_set_keep_unknown_chunks,
-    (png_structp png_ptr, int keep,
-    png_const_bytep chunk_list, int num_chunks));
-
-/* The handling code is returned; the result is therefore true (non-zero) if
- * special handling is required, false for the default handling.
- */
-PNG_EXPORT(173, int, png_handle_as_unknown, (png_structp png_ptr,
-    png_const_bytep chunk_name));
-#endif
-#ifdef PNG_UNKNOWN_CHUNKS_SUPPORTED
-PNG_EXPORT(174, void, png_set_unknown_chunks, (png_structp png_ptr,
-    png_infop info_ptr, png_const_unknown_chunkp unknowns,
-    int num_unknowns));
-PNG_EXPORT(175, void, png_set_unknown_chunk_location,
-    (png_structp png_ptr, png_infop info_ptr, int chunk, int location));
-PNG_EXPORT(176, int, png_get_unknown_chunks, (png_const_structp png_ptr,
-    png_const_infop info_ptr, png_unknown_chunkpp entries));
-#endif
-
-/* Png_free_data() will turn off the "valid" flag for anything it frees.
- * 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);
- */
-PNG_EXPORT(177, void, png_set_invalid,
-    (png_structp png_ptr, png_infop info_ptr, int mask));
-
-#ifdef PNG_INFO_IMAGE_SUPPORTED
-/* The "params" pointer is currently not used and is for future expansion. */
-PNG_EXPORT(178, void, png_read_png, (png_structp png_ptr, png_infop info_ptr,
-    int transforms, png_voidp params));
-PNG_EXPORT(179, void, png_write_png, (png_structp png_ptr, png_infop info_ptr,
-    int transforms, png_voidp params));
-#endif
-
-PNG_EXPORT(180, png_const_charp, png_get_copyright,
-    (png_const_structp png_ptr));
-PNG_EXPORT(181, png_const_charp, png_get_header_ver,
-    (png_const_structp png_ptr));
-PNG_EXPORT(182, png_const_charp, png_get_header_version,
-    (png_const_structp png_ptr));
-PNG_EXPORT(183, png_const_charp, png_get_libpng_ver,
-    (png_const_structp png_ptr));
-
-#ifdef PNG_MNG_FEATURES_SUPPORTED
-PNG_EXPORT(184, png_uint_32, png_permit_mng_features, (png_structp png_ptr,
-    png_uint_32 mng_features_permitted));
-#endif
-
-/* 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
-
-/* Strip the prepended error numbers ("#nnn ") from error and warning
- * messages before passing them to the error or warning handler.
- */
-#ifdef PNG_ERROR_NUMBERS_SUPPORTED
-PNG_EXPORT(185, void, png_set_strip_error_numbers,
-    (png_structp png_ptr,
-    png_uint_32 strip_mode));
-#endif
-
-/* Added in libpng-1.2.6 */
-#ifdef PNG_SET_USER_LIMITS_SUPPORTED
-PNG_EXPORT(186, void, png_set_user_limits, (png_structp png_ptr,
-    png_uint_32 user_width_max, png_uint_32 user_height_max));
-PNG_EXPORT(187, png_uint_32, png_get_user_width_max,
-    (png_const_structp png_ptr));
-PNG_EXPORT(188, png_uint_32, png_get_user_height_max,
-    (png_const_structp png_ptr));
-/* Added in libpng-1.4.0 */
-PNG_EXPORT(189, void, png_set_chunk_cache_max, (png_structp png_ptr,
-    png_uint_32 user_chunk_cache_max));
-PNG_EXPORT(190, png_uint_32, png_get_chunk_cache_max,
-    (png_const_structp png_ptr));
-/* Added in libpng-1.4.1 */
-PNG_EXPORT(191, void, png_set_chunk_malloc_max, (png_structp png_ptr,
-    png_alloc_size_t user_chunk_cache_max));
-PNG_EXPORT(192, png_alloc_size_t, png_get_chunk_malloc_max,
-    (png_const_structp png_ptr));
-#endif
-
-#if defined(PNG_INCH_CONVERSIONS_SUPPORTED)
-PNG_EXPORT(193, png_uint_32, png_get_pixels_per_inch,
-    (png_const_structp png_ptr, png_const_infop info_ptr));
-
-PNG_EXPORT(194, png_uint_32, png_get_x_pixels_per_inch,
-    (png_const_structp png_ptr, png_const_infop info_ptr));
-
-PNG_EXPORT(195, png_uint_32, png_get_y_pixels_per_inch,
-    (png_const_structp png_ptr, png_const_infop info_ptr));
-
-PNG_FP_EXPORT(196, float, png_get_x_offset_inches,
-    (png_const_structp png_ptr, png_const_infop info_ptr))
-#ifdef PNG_FIXED_POINT_SUPPORTED /* otherwise not implemented. */
-PNG_FIXED_EXPORT(211, png_fixed_point, png_get_x_offset_inches_fixed,
-    (png_structp png_ptr, png_const_infop info_ptr))
-#endif
-
-PNG_FP_EXPORT(197, float, png_get_y_offset_inches, (png_const_structp png_ptr,
-    png_const_infop info_ptr))
-#ifdef PNG_FIXED_POINT_SUPPORTED /* otherwise not implemented. */
-PNG_FIXED_EXPORT(212, png_fixed_point, png_get_y_offset_inches_fixed,
-    (png_structp png_ptr, png_const_infop info_ptr))
-#endif
-
-#  ifdef PNG_pHYs_SUPPORTED
-PNG_EXPORT(198, png_uint_32, png_get_pHYs_dpi, (png_const_structp png_ptr,
-    png_const_infop info_ptr, png_uint_32 *res_x, png_uint_32 *res_y,
-    int *unit_type));
-#  endif /* PNG_pHYs_SUPPORTED */
-#endif  /* PNG_INCH_CONVERSIONS_SUPPORTED */
-
-/* Added in libpng-1.4.0 */
-#ifdef PNG_IO_STATE_SUPPORTED
-PNG_EXPORT(199, png_uint_32, png_get_io_state, (png_structp png_ptr));
-
-PNG_EXPORTA(200, png_const_bytep, png_get_io_chunk_name,
-    (png_structp png_ptr), PNG_DEPRECATED);
-PNG_EXPORT(216, png_uint_32, png_get_io_chunk_type,
-    (png_const_structp png_ptr));
-
-/* The flags returned by png_get_io_state() are the following: */
-#  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 */
-#endif /* ?PNG_IO_STATE_SUPPORTED */
-
-/* Interlace support.  The following macros are always defined so that if
- * libpng interlace handling is turned off the macros may be used to handle
- * interlaced images within the application.
- */
-#define PNG_INTERLACE_ADAM7_PASSES 7
-
-/* Two macros to return the first row and first column of the original,
- * full, image which appears in a given pass.  'pass' is in the range 0
- * to 6 and the result is in the range 0 to 7.
- */
-#define PNG_PASS_START_ROW(pass) (((1&~(pass))<<(3-((pass)>>1)))&7)
-#define PNG_PASS_START_COL(pass) (((1& (pass))<<(3-(((pass)+1)>>1)))&7)
-
-/* A macro to return the offset between pixels in the output row for a pair of
- * pixels in the input - effectively the inverse of the 'COL_SHIFT' macro that
- * follows.  Note that ROW_OFFSET is the offset from one row to the next whereas
- * COL_OFFSET is from one column to the next, within a row.
- */
-#define PNG_PASS_ROW_OFFSET(pass) ((pass)>2?(8>>(((pass)-1)>>1)):8)
-#define PNG_PASS_COL_OFFSET(pass) (1<<((7-(pass))>>1))
-
-/* Two macros to help evaluate the number of rows or columns in each
- * pass.  This is expressed as a shift - effectively log2 of the number or
- * rows or columns in each 8x8 tile of the original image.
- */
-#define PNG_PASS_ROW_SHIFT(pass) ((pass)>2?(8-(pass))>>1:3)
-#define PNG_PASS_COL_SHIFT(pass) ((pass)>1?(7-(pass))>>1:3)
-
-/* Hence two macros to determine the number of rows or columns in a given
- * pass of an image given its height or width.  In fact these macros may
- * return non-zero even though the sub-image is empty, because the other
- * dimension may be empty for a small image.
- */
-#define PNG_PASS_ROWS(height, pass) (((height)+(((1<<PNG_PASS_ROW_SHIFT(pass))\
-   -1)-PNG_PASS_START_ROW(pass)))>>PNG_PASS_ROW_SHIFT(pass))
-#define PNG_PASS_COLS(width, pass) (((width)+(((1<<PNG_PASS_COL_SHIFT(pass))\
-   -1)-PNG_PASS_START_COL(pass)))>>PNG_PASS_COL_SHIFT(pass))
-
-/* For the reader row callbacks (both progressive and sequential) it is
- * necessary to find the row in the output image given a row in an interlaced
- * image, so two more macros:
- */
-#define PNG_ROW_FROM_PASS_ROW(yIn, pass) \
-   (((yIn)<<PNG_PASS_ROW_SHIFT(pass))+PNG_PASS_START_ROW(pass))
-#define PNG_COL_FROM_PASS_COL(xIn, pass) \
-   (((xIn)<<PNG_PASS_COL_SHIFT(pass))+PNG_PASS_START_COL(pass))
-
-/* Two macros which return a boolean (0 or 1) saying whether the given row
- * or column is in a particular pass.  These use a common utility macro that
- * returns a mask for a given pass - the offset 'off' selects the row or
- * column version.  The mask has the appropriate bit set for each column in
- * the tile.
- */
-#define PNG_PASS_MASK(pass,off) ( \
-   ((0x110145AF>>(((7-(off))-(pass))<<2)) & 0xF) | \
-   ((0x01145AF0>>(((7-(off))-(pass))<<2)) & 0xF0))
-
-#define PNG_ROW_IN_INTERLACE_PASS(y, pass) \
-   ((PNG_PASS_MASK(pass,0) >> ((y)&7)) & 1)
-#define PNG_COL_IN_INTERLACE_PASS(x, pass) \
-   ((PNG_PASS_MASK(pass,1) >> ((x)&7)) & 1)
-
-#ifdef PNG_READ_COMPOSITE_NODIV_SUPPORTED
-/* 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
- * 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. :-) ]
- */
-
- /* fg and bg should be in `gamma 1.0' space; alpha is the opacity */
-
-#  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)) + 128);                \
-       (composite) = (png_byte)((temp + (temp >> 8)) >> 8); }
-
-#  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)*(65535                      \
-           - (png_uint_32)(alpha)) + 32768);               \
-       (composite) = (png_uint_16)((temp + (temp >> 16)) >> 16); }
-
-#else  /* Standard method using integer division */
-
-#  define png_composite(composite, fg, alpha, bg)                          \
-     (composite) = (png_byte)(((png_uint_16)(fg) * (png_uint_16)(alpha) +  \
-     (png_uint_16)(bg) * (png_uint_16)(255 - (png_uint_16)(alpha)) +       \
-     127) / 255)
-
-#  define png_composite_16(composite, fg, alpha, bg)                         \
-     (composite) = (png_uint_16)(((png_uint_32)(fg) * (png_uint_32)(alpha) + \
-     (png_uint_32)(bg)*(png_uint_32)(65535 - (png_uint_32)(alpha)) +         \
-     32767) / 65535)
-#endif /* PNG_READ_COMPOSITE_NODIV_SUPPORTED */
-
-#ifdef PNG_READ_INT_FUNCTIONS_SUPPORTED
-PNG_EXPORT(201, png_uint_32, png_get_uint_32, (png_const_bytep buf));
-PNG_EXPORT(202, png_uint_16, png_get_uint_16, (png_const_bytep buf));
-PNG_EXPORT(203, png_int_32, png_get_int_32, (png_const_bytep buf));
-#endif
-
-PNG_EXPORT(204, png_uint_32, png_get_uint_31, (png_structp png_ptr,
-    png_const_bytep buf));
-/* No png_get_int_16 -- may be added if there's a real need for it. */
-
-/* Place a 32-bit number into a buffer in PNG byte order (big-endian). */
-#ifdef PNG_WRITE_INT_FUNCTIONS_SUPPORTED
-PNG_EXPORT(205, void, png_save_uint_32, (png_bytep buf, png_uint_32 i));
-#endif
-#ifdef PNG_SAVE_INT_32_SUPPORTED
-PNG_EXPORT(206, void, png_save_int_32, (png_bytep buf, png_int_32 i));
-#endif
-
-/* 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.
- */
-#ifdef PNG_WRITE_INT_FUNCTIONS_SUPPORTED
-PNG_EXPORT(207, void, png_save_uint_16, (png_bytep buf, unsigned int i));
-/* No png_save_int_16 -- may be added if there's a real need for it. */
-#endif
-
-#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.
- */
-#  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))))
-
-   /* From libpng-1.4.0 until 1.4.4, the png_get_uint_16 macro (but not the
-    * function) incorrectly returned a value of type png_uint_32.
-    */
-#  define png_get_uint_16(buf) \
-     ((png_uint_16) \
-      (((unsigned int)(*(buf)) << 8) + \
-       ((unsigned int)(*((buf) + 1)))))
-
-#  define png_get_int_32(buf) \
-     ((png_int_32)((*(buf) & 0x80) \
-      ? -((png_int_32)((png_get_uint_32(buf) ^ 0xffffffffL) + 1)) \
-      : (png_int_32)png_get_uint_32(buf)))
-#endif
-
-#if defined(PNG_READ_CHECK_FOR_INVALID_INDEX_SUPPORTED) || \
-    defined(PNG_WRITE_CHECK_FOR_INVALID_INDEX_SUPPORTED)
-PNG_EXPORT(234, void, png_set_check_for_invalid_index, (png_structp png_ptr,
-    int allowed));
-#endif
-
-/* Maintainer: Put new public prototypes here ^, in libpng.3, and project
- * defs
- */
-
-/* The last ordinal number (this is the *last* one already used; the next
- * one to use is one more than this.)  Maintainer, remember to add an entry to
- * scripts/symbols.def as well.
- */
-#ifdef PNG_EXPORT_LAST_ORDINAL
-  PNG_EXPORT_LAST_ORDINAL(234);
-#endif
-
-#ifdef __cplusplus
-}
-#endif
-
-#endif /* PNG_VERSION_INFO_ONLY */
-/* Do not put anything past this line */
-#endif /* PNG_H */
+
+/* png.h - header file for PNG reference library
+ *
+ * libpng version 1.5.13 - September 27, 2012
+ * Copyright (c) 1998-2012 Glenn Randers-Pehrson
+ * (Version 0.96 Copyright (c) 1996, 1997 Andreas Dilger)
+ * (Version 0.88 Copyright (c) 1995, 1996 Guy Eric Schalnat, Group 42, Inc.)
+ *
+ * This code is released under the libpng license (See LICENSE, below)
+ *
+ * Authors and maintainers:
+ *   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
+ *   libpng versions 0.97, January 1998, through 1.5.13 - September 27, 2012: Glenn
+ *   See also "Contributing Authors", below.
+ *
+ * Note about libpng version numbers:
+ *
+ *   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:
+ *
+ *    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)
+ *    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
+ *    1.0.9                    1    10009  2.1.0.9
+ *    1.0.10beta1              1    10010  2.1.0.10beta1
+ *    1.0.10rc1                1    10010  2.1.0.10rc1
+ *    1.0.10                   1    10010  2.1.0.10
+ *    1.0.11beta1-3            1    10011  2.1.0.11beta1-3
+ *    1.0.11rc1                1    10011  2.1.0.11rc1
+ *    1.0.11                   1    10011  2.1.0.11
+ *    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)
+ *    1.2.0beta1-2             2    10200  2.1.2.0beta1-2
+ *    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
+ *    1.2.1beta1-4             3    10201  3.1.2.1beta1-4
+ *    1.2.1rc1-2               3    10201  3.1.2.1rc1-2
+ *    1.2.1                    3    10201  3.1.2.1
+ *    1.2.2beta1-6            12    10202  12.so.0.1.2.2beta1-6
+ *    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
+ *    1.0.13                  10    10013  10.so.0.1.0.13
+ *    1.2.2                   12    10202  12.so.0.1.2.2
+ *    1.2.3rc1-6              12    10203  12.so.0.1.2.3rc1-6
+ *    1.2.3                   12    10203  12.so.0.1.2.3
+ *    1.2.4beta1-3            13    10204  12.so.0.1.2.4beta1-3
+ *    1.0.14rc1               13    10014  10.so.0.1.0.14rc1
+ *    1.2.4rc1                13    10204  12.so.0.1.2.4rc1
+ *    1.0.14                  10    10014  10.so.0.1.0.14
+ *    1.2.4                   13    10204  12.so.0.1.2.4
+ *    1.2.5beta1-2            13    10205  12.so.0.1.2.5beta1-2
+ *    1.0.15rc1-3             10    10015  10.so.0.1.0.15rc1-3
+ *    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
+ *    1.2.6beta1-4            13    10206  12.so.0.1.2.6beta1-4
+ *    1.0.16                  10    10016  10.so.0.1.0.16
+ *    1.2.6                   13    10206  12.so.0.1.2.6
+ *    1.2.7beta1-2            13    10207  12.so.0.1.2.7beta1-2
+ *    1.0.17rc1               10    10017  12.so.0.1.0.17rc1
+ *    1.2.7rc1                13    10207  12.so.0.1.2.7rc1
+ *    1.0.17                  10    10017  12.so.0.1.0.17
+ *    1.2.7                   13    10207  12.so.0.1.2.7
+ *    1.2.8beta1-5            13    10208  12.so.0.1.2.8beta1-5
+ *    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
+ *    1.0.18                  10    10018  12.so.0.1.0.18
+ *    1.2.8                   13    10208  12.so.0.1.2.8
+ *    1.2.9beta1-3            13    10209  12.so.0.1.2.9beta1-3
+ *    1.2.9beta4-11           13    10209  12.so.0.9[.0]
+ *    1.2.9rc1                13    10209  12.so.0.9[.0]
+ *    1.2.9                   13    10209  12.so.0.9[.0]
+ *    1.2.10beta1-7           13    10210  12.so.0.10[.0]
+ *    1.2.10rc1-2             13    10210  12.so.0.10[.0]
+ *    1.2.10                  13    10210  12.so.0.10[.0]
+ *    1.4.0beta1-5            14    10400  14.so.0.0[.0]
+ *    1.2.11beta1-4           13    10211  12.so.0.11[.0]
+ *    1.4.0beta7-8            14    10400  14.so.0.0[.0]
+ *    1.2.11                  13    10211  12.so.0.11[.0]
+ *    1.2.12                  13    10212  12.so.0.12[.0]
+ *    1.4.0beta9-14           14    10400  14.so.0.0[.0]
+ *    1.2.13                  13    10213  12.so.0.13[.0]
+ *    1.4.0beta15-36          14    10400  14.so.0.0[.0]
+ *    1.4.0beta37-87          14    10400  14.so.14.0[.0]
+ *    1.4.0rc01               14    10400  14.so.14.0[.0]
+ *    1.4.0beta88-109         14    10400  14.so.14.0[.0]
+ *    1.4.0rc02-08            14    10400  14.so.14.0[.0]
+ *    1.4.0                   14    10400  14.so.14.0[.0]
+ *    1.4.1beta01-03          14    10401  14.so.14.1[.0]
+ *    1.4.1rc01               14    10401  14.so.14.1[.0]
+ *    1.4.1beta04-12          14    10401  14.so.14.1[.0]
+ *    1.4.1                   14    10401  14.so.14.1[.0]
+ *    1.4.2                   14    10402  14.so.14.2[.0]
+ *    1.4.3                   14    10403  14.so.14.3[.0]
+ *    1.4.4                   14    10404  14.so.14.4[.0]
+ *    1.5.0beta01-58          15    10500  15.so.15.0[.0]
+ *    1.5.0rc01-07            15    10500  15.so.15.0[.0]
+ *    1.5.0                   15    10500  15.so.15.0[.0]
+ *    1.5.1beta01-11          15    10501  15.so.15.1[.0]
+ *    1.5.1rc01-02            15    10501  15.so.15.1[.0]
+ *    1.5.1                   15    10501  15.so.15.1[.0]
+ *    1.5.2beta01-03          15    10502  15.so.15.2[.0]
+ *    1.5.2rc01-03            15    10502  15.so.15.2[.0]
+ *    1.5.2                   15    10502  15.so.15.2[.0]
+ *    1.5.3beta01-10          15    10503  15.so.15.3[.0]
+ *    1.5.3rc01-02            15    10503  15.so.15.3[.0]
+ *    1.5.3beta11             15    10503  15.so.15.3[.0]
+ *    1.5.3 [omitted]
+ *    1.5.4beta01-08          15    10504  15.so.15.4[.0]
+ *    1.5.4rc01               15    10504  15.so.15.4[.0]
+ *    1.5.4                   15    10504  15.so.15.4[.0]
+ *    1.5.5beta01-08          15    10505  15.so.15.5[.0]
+ *    1.5.5rc01               15    10505  15.so.15.5[.0]
+ *    1.5.5                   15    10505  15.so.15.5[.0]
+ *    1.5.6beta01-07          15    10506  15.so.15.6[.0]
+ *    1.5.6rc01-03            15    10506  15.so.15.6[.0]
+ *    1.5.6                   15    10506  15.so.15.6[.0]
+ *    1.5.7beta01-05          15    10507  15.so.15.7[.0]
+ *    1.5.7rc01-03            15    10507  15.so.15.7[.0]
+ *    1.5.7                   15    10507  15.so.15.7[.0]
+ *    1.5.8beta01             15    10508  15.so.15.8[.0]
+ *    1.5.8rc01               15    10508  15.so.15.8[.0]
+ *    1.5.8                   15    10508  15.so.15.8[.0]
+ *    1.5.9beta01-02          15    10509  15.so.15.9[.0]
+ *    1.5.9rc01               15    10509  15.so.15.9[.0]
+ *    1.5.9                   15    10509  15.so.15.9[.0]
+ *    1.5.10beta01-05         15    10510  15.so.15.10[.0]
+ *    1.5.10                  15    10510  15.so.15.10[.0]
+ *    1.5.11beta01            15    10511  15.so.15.11[.0]
+ *    1.5.11rc01-05           15    10511  15.so.15.11[.0]
+ *    1.5.11                  15    10511  15.so.15.11[.0]
+ *    1.5.12                  15    10512  15.so.15.12[.0]
+ *    1.5.13beta01-02         15    10513  15.so.15.13[.0]
+ *    1.5.13rc01              15    10513  15.so.15.13[.0]
+ *    1.5.13                  15    10513  15.so.15.13[.0]
+ *
+ *   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 "rcNN".
+ *
+ *   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.
+ *
+ *   DLLNUM will change each time there are forward or backward changes
+ *   in binary compatibility (e.g., when a new feature is added).
+ *
+ * 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/
+ */
+
+/*
+ * COPYRIGHT NOTICE, DISCLAIMER, and LICENSE:
+ *
+ * If you modify libpng you may insert additional notices immediately following
+ * this sentence.
+ *
+ * This code is released under the libpng license.
+ *
+ * libpng versions 1.2.6, August 15, 2004, through 1.5.13, September 27, 2012, are
+ * Copyright (c) 2004, 2006-2012 Glenn Randers-Pehrson, and are
+ * distributed according to the same disclaimer and license as libpng-1.2.5
+ * with the following individual added to the list of Contributing Authors:
+ *
+ *    Cosmin Truta
+ *
+ * libpng versions 1.0.7, July 1, 2000, through 1.2.5, October 3, 2002, are
+ * Copyright (c) 2000-2002 Glenn Randers-Pehrson, and are
+ * distributed according to the same disclaimer and license as libpng-1.0.6
+ * with the following individuals added to the list of Contributing Authors:
+ *
+ *    Simon-Pierre Cadieux
+ *    Eric S. Raymond
+ *    Gilles Vollant
+ *
+ * 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
+ * Copyright (c) 1998, 1999, 2000 Glenn Randers-Pehrson, and are
+ * distributed according to the same disclaimer and license as libpng-0.96,
+ * 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:
+ *
+ *    John Bowler
+ *    Kevin Bracey
+ *    Sam Bushell
+ *    Magnus Holmgren
+ *    Greg Roelofs
+ *    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
+ *    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:
+ *
+ *   1. The origin of this source code must not be misrepresented.
+ *
+ *   2. Altered versions must be plainly marked as such and must not
+ *      be misrepresented as being the original source.
+ *
+ *   3. This Copyright notice may not be removed or altered from
+ *      any source or altered source distribution.
+ *
+ * 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.
+ */
+
+/*
+ * A "png_get_copyright" function is available, for convenient use in "about"
+ * boxes and the like:
+ *
+ *     printf("%s", png_get_copyright(NULL));
+ *
+ * Also, the PNG logo (in PNG format, of course) is supplied in the
+ * files "pngbar.png" and "pngbar.jpg (88x31) and "pngnow.png" (98x31).
+ */
+
+/*
+ * 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.
+ */
+
+/*
+ * Y2K compliance in libpng:
+ * =========================
+ *
+ *    September 27, 2012
+ *
+ *    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
+ *    upward through 1.5.13 are Y2K compliant.  It is my belief that
+ *    earlier versions were also Y2K compliant.
+ *
+ *    Libpng only has two year fields.  One is a 2-byte unsigned integer
+ *    that will hold years up to 65535.  The other holds the date in text
+ *    format, and will hold years up to 9999.
+ *
+ *    The integer is
+ *        "png_uint_16 year" in png_time_struct.
+ *
+ *    The string is
+ *        "char time_buffer[29]" in png_struct.  This will be no
+ *    longer used in libpng-1.6.0 and will be removed from libpng-1.7.0.
+ *
+ *    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
+ */
+
+#ifndef PNG_H
+#define PNG_H
+
+/* This is not the place to learn how to use libpng. The file libpng-manual.txt
+ * 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.
+ *
+ * If you just need to read a PNG file and don't want to read the documentation
+ * skip to the end of this file and read the section entitled 'simplified API'.
+ */
+
+/* Version information for png.h - this should match the version in png.c */
+#define PNG_LIBPNG_VER_STRING "1.5.13"
+#define PNG_HEADER_VERSION_STRING \
+     " libpng version 1.5.13 - September 27, 2012\n"
+
+#define PNG_LIBPNG_VER_SONUM   15
+#define PNG_LIBPNG_VER_DLLNUM  15
+
+/* These should match the first 3 components of PNG_LIBPNG_VER_STRING: */
+#define PNG_LIBPNG_VER_MAJOR   1
+#define PNG_LIBPNG_VER_MINOR   5
+#define PNG_LIBPNG_VER_RELEASE 13
+
+/* This should match the numeric part of the final component of
+ * PNG_LIBPNG_VER_STRING, omitting any leading zero:
+ */
+
+#define PNG_LIBPNG_VER_BUILD  0
+
+/* Release Status */
+#define PNG_LIBPNG_BUILD_ALPHA    1
+#define PNG_LIBPNG_BUILD_BETA     2
+#define PNG_LIBPNG_BUILD_RC       3
+#define PNG_LIBPNG_BUILD_STABLE   4
+#define PNG_LIBPNG_BUILD_RELEASE_STATUS_MASK 7
+
+/* 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 */
+
+#define PNG_LIBPNG_BUILD_BASE_TYPE PNG_LIBPNG_BUILD_STABLE
+
+/* 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
+ * version 1.0.1 it's    xxyyzz, where x=major, y=minor, z=release
+ */
+#define PNG_LIBPNG_VER 10513 /* 1.5.13 */
+
+/* Library configuration: these options cannot be changed after
+ * the library has been built.
+ */
+#ifndef PNGLCONF_H
+    /* If pnglibconf.h is missing, you can
+     * copy scripts/pnglibconf.h.prebuilt to pnglibconf.h
+     */
+#   include "pnglibconf.h"
+#endif
+
+#ifndef PNG_VERSION_INFO_ONLY
+#  ifndef PNG_BUILDING_SYMBOL_TABLE
+  /*
+   *   Standard header files (not needed for the version info or while
+   *   building symbol table -- see scripts/pnglibconf.dfa)
+   */
+#    ifdef PNG_SETJMP_SUPPORTED
+#      include <setjmp.h>
+#    endif
+
+    /* 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
+#  endif
+
+/* Machine specific configuration. */
+#  include "pngconf.h"
+#endif
+
+/*
+ * Added at libpng-1.2.8
+ *
+ * Ref MSDN: Private as priority over Special
+ * VS_FF_PRIVATEBUILD File *was not* built using standard release
+ * procedures. If this value is given, the StringFileInfo block must
+ * contain a PrivateBuild string.
+ *
+ * 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
+ * StringFileInfo block must contain a SpecialBuild string.
+ */
+
+#ifdef PNG_USER_PRIVATEBUILD /* From pnglibconf.h */
+#  define PNG_LIBPNG_BUILD_TYPE \
+       (PNG_LIBPNG_BUILD_BASE_TYPE | PNG_LIBPNG_BUILD_PRIVATE)
+#else
+#  ifdef PNG_LIBPNG_SPECIALBUILD
+#    define PNG_LIBPNG_BUILD_TYPE \
+         (PNG_LIBPNG_BUILD_BASE_TYPE | PNG_LIBPNG_BUILD_SPECIAL)
+#  else
+#    define PNG_LIBPNG_BUILD_TYPE (PNG_LIBPNG_BUILD_BASE_TYPE)
+#  endif
+#endif
+
+#ifndef PNG_VERSION_INFO_ONLY
+
+/* Inhibit C++ name-mangling for libpng functions but not for system calls. */
+#ifdef __cplusplus
+extern "C" {
+#endif /* __cplusplus */
+
+/* Version information for C files, stored in png.c.  This had better match
+ * the version above.
+ */
+#define png_libpng_ver png_get_header_ver(NULL)
+
+/* This file is arranged in several sections:
+ *
+ * 1. Any configuration options that can be specified by for the application
+ *    code when it is built.  (Build time configuration is in pnglibconf.h)
+ * 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
+ * See pnglibconf.h for build time configuration
+ *
+ * Run time configuration allows the application to choose between
+ * implementations of certain arithmetic APIs.  The default is set
+ * at build time and recorded in pnglibconf.h, but it is safe to
+ * 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
+ */
+
+/* This triggers a compiler error in png.c, if png.c and png.h
+ * do not agree upon the version number.
+ */
+typedef char* png_libpng_version_1_5_13;
+
+/* 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).
+ */
+typedef struct png_color_struct
+{
+   png_byte red;
+   png_byte green;
+   png_byte blue;
+} png_color;
+typedef png_color FAR * png_colorp;
+typedef PNG_CONST png_color FAR * png_const_colorp;
+typedef png_color FAR * FAR * png_colorpp;
+
+typedef struct png_color_16_struct
+{
+   png_byte index;    /* used for palette files */
+   png_uint_16 red;   /* for use in red green blue files */
+   png_uint_16 green;
+   png_uint_16 blue;
+   png_uint_16 gray;  /* for use in grayscale files */
+} png_color_16;
+typedef png_color_16 FAR * png_color_16p;
+typedef PNG_CONST png_color_16 FAR * png_const_color_16p;
+typedef png_color_16 FAR * FAR * png_color_16pp;
+
+typedef struct png_color_8_struct
+{
+   png_byte red;   /* for use in red green blue files */
+   png_byte green;
+   png_byte blue;
+   png_byte gray;  /* for use in grayscale files */
+   png_byte alpha; /* for alpha channel files */
+} png_color_8;
+typedef png_color_8 FAR * png_color_8p;
+typedef PNG_CONST png_color_8 FAR * png_const_color_8p;
+typedef png_color_8 FAR * FAR * png_color_8pp;
+
+/*
+ * The following two structures are used for the in-core representation
+ * of sPLT chunks.
+ */
+typedef struct png_sPLT_entry_struct
+{
+   png_uint_16 red;
+   png_uint_16 green;
+   png_uint_16 blue;
+   png_uint_16 alpha;
+   png_uint_16 frequency;
+} png_sPLT_entry;
+typedef png_sPLT_entry FAR * png_sPLT_entryp;
+typedef PNG_CONST png_sPLT_entry FAR * png_const_sPLT_entryp;
+typedef png_sPLT_entry FAR * FAR * png_sPLT_entrypp;
+
+/*  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.
+ */
+
+typedef struct png_sPLT_struct
+{
+   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 */
+} png_sPLT_t;
+typedef png_sPLT_t FAR * png_sPLT_tp;
+typedef PNG_CONST png_sPLT_t FAR * png_const_sPLT_tp;
+typedef png_sPLT_t FAR * FAR * png_sPLT_tpp;
+
+#ifdef PNG_TEXT_SUPPORTED
+/* 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
+ * points to a regular zero-terminated C string.  The "text" fields can be a
+ * regular C string, an empty string, or a NULL pointer.
+ * However, the structure returned by png_get_text() will always contain
+ * the "text" field as a regular zero-terminated C string (possibly
+ * empty), never a NULL pointer, so it can be safely used in printf() and
+ * other string-handling functions.  Note that the "itxt_length", "lang", and
+ * "lang_key" members of the structure only exist when the library is built
+ * with iTXt chunk support.  Prior to libpng-1.4.0 the library was built by
+ * default without iTXt support. Also note that when iTXt *is* supported,
+ * the "lang" and "lang_key" fields contain NULL pointers when the
+ * "compression" field contains * PNG_TEXT_COMPRESSION_NONE or
+ * PNG_TEXT_COMPRESSION_zTXt. Note that the "compression value" is not the
+ * same as what appears in the PNG tEXt/zTXt/iTXt chunk's "compression flag"
+ * which is always 0 or 1, or its "compression method" which is always 0.
+ */
+typedef struct png_text_struct
+{
+   int  compression;       /* compression value:
+                             -1: tEXt, none
+                              0: zTXt, deflate
+                              1: iTXt, none
+                              2: iTXt, deflate  */
+   png_charp key;          /* keyword, 1-79 character description of "text" */
+   png_charp text;         /* comment, may be an empty string (ie "")
+                              or a NULL pointer */
+   png_size_t text_length; /* length of the text string */
+   png_size_t itxt_length; /* length of the itxt string */
+   png_charp lang;         /* language code, 0-79 characters
+                              or a NULL pointer */
+   png_charp lang_key;     /* keyword translated UTF-8 string, 0 or more
+                              chars or a NULL pointer */
+} png_text;
+typedef png_text FAR * png_textp;
+typedef PNG_CONST png_text FAR * png_const_textp;
+typedef png_text FAR * FAR * png_textpp;
+#endif
+
+/* 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
+#define PNG_ITXT_COMPRESSION_NONE     1
+#define PNG_ITXT_COMPRESSION_zTXt     2
+#define PNG_TEXT_COMPRESSION_LAST     3  /* Not a valid value */
+
+/* png_time is a way to hold the time in an machine independent way.
+ * 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
+ * note - PNG has always been Year 2000 compliant!
+ */
+typedef struct png_time_struct
+{
+   png_uint_16 year; /* full year, as in, 1995 */
+   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) */
+} png_time;
+typedef png_time FAR * png_timep;
+typedef PNG_CONST png_time FAR * png_const_timep;
+typedef png_time FAR * FAR * png_timepp;
+
+#if defined(PNG_UNKNOWN_CHUNKS_SUPPORTED) || \
+    defined(PNG_HANDLE_AS_UNKNOWN_SUPPORTED)
+/* 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;
+
+    /* libpng-using applications should NOT directly modify this byte. */
+    png_byte location; /* mode of operation at read time */
+}
+
+
+png_unknown_chunk;
+typedef png_unknown_chunk FAR * png_unknown_chunkp;
+typedef PNG_CONST png_unknown_chunk FAR * png_const_unknown_chunkp;
+typedef png_unknown_chunk FAR * FAR * png_unknown_chunkpp;
+#endif
+
+/* Values for the unknown chunk location byte */
+
+#define PNG_HAVE_IHDR  0x01
+#define PNG_HAVE_PLTE  0x02
+#define PNG_AFTER_IDAT 0x08
+
+/* The complete definition of png_info has, as of libpng-1.5.0,
+ * been moved into a separate header file that is not accessible to
+ * applications.  Read libpng-manual.txt or libpng.3 for more info.
+ */
+typedef struct png_info_def png_info;
+typedef png_info FAR * png_infop;
+typedef PNG_CONST png_info FAR * png_const_infop;
+typedef png_info FAR * FAR * png_infopp;
+
+/* Maximum positive integer used in PNG is (2^31)-1 */
+#define PNG_UINT_31_MAX ((png_uint_32)0x7fffffffL)
+#define PNG_UINT_32_MAX ((png_uint_32)(-1))
+#define PNG_SIZE_MAX ((png_size_t)(-1))
+
+/* These are constants for fixed point values encoded in the
+ * PNG specification manner (x100000)
+ */
+#define PNG_FP_1    100000
+#define PNG_FP_HALF  50000
+#define PNG_FP_MAX  ((png_fixed_point)0x7fffffffL)
+#define PNG_FP_MIN  (-PNG_FP_MAX)
+
+/* These describe the color_type field in png_info. */
+/* color type masks */
+#define PNG_COLOR_MASK_PALETTE    1
+#define PNG_COLOR_MASK_COLOR      2
+#define PNG_COLOR_MASK_ALPHA      4
+
+/* color types.  Note that not all combinations are legal */
+#define PNG_COLOR_TYPE_GRAY 0
+#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)
+#define PNG_COLOR_TYPE_GRAY_ALPHA (PNG_COLOR_MASK_ALPHA)
+/* aliases */
+#define PNG_COLOR_TYPE_RGBA  PNG_COLOR_TYPE_RGB_ALPHA
+#define PNG_COLOR_TYPE_GA  PNG_COLOR_TYPE_GRAY_ALPHA
+
+/* This is for compression type. PNG 1.0-1.2 only define the single type. */
+#define PNG_COMPRESSION_TYPE_BASE 0 /* Deflate method 8, 32K window */
+#define PNG_COMPRESSION_TYPE_DEFAULT PNG_COMPRESSION_TYPE_BASE
+
+/* This is for filter type. PNG 1.0-1.2 only define the single type. */
+#define PNG_FILTER_TYPE_BASE      0 /* Single row per-byte filtering */
+#define PNG_INTRAPIXEL_DIFFERENCING 64 /* Used only in MNG datastreams */
+#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 */
+
+/* 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 */
+
+/* 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 */
+
+/* These are for the sRGB chunk.  These values should NOT be changed. */
+#define PNG_sRGB_INTENT_PERCEPTUAL 0
+#define PNG_sRGB_INTENT_RELATIVE   1
+#define PNG_sRGB_INTENT_SATURATION 2
+#define PNG_sRGB_INTENT_ABSOLUTE   3
+#define PNG_sRGB_INTENT_LAST       4 /* Not a valid value */
+
+/* This is for text chunks */
+#define PNG_KEYWORD_MAX_LENGTH     79
+
+/* Maximum number of entries in PLTE/sPLT/tRNS arrays */
+#define PNG_MAX_PALETTE_LENGTH    256
+
+/* 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.
+ */
+#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
+#define PNG_INFO_pCAL 0x0400
+#define PNG_INFO_sRGB 0x0800   /* GR-P, 0.96a */
+#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 */
+#define PNG_INFO_IDAT 0x8000   /* ESR, 1.0.6 */
+
+/* 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.
+ */
+typedef struct png_row_info_struct
+{
+   png_uint_32 width;    /* width of row */
+   png_size_t rowbytes;  /* number of bytes in row */
+   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) */
+} png_row_info;
+
+typedef png_row_info FAR * png_row_infop;
+typedef png_row_info FAR * FAR * png_row_infopp;
+
+/* The complete definition of png_struct has, as of libpng-1.5.0,
+ * been moved into a separate header file that is not accessible to
+ * applications.  Read libpng-manual.txt or libpng.3 for more info.
+ */
+typedef struct png_struct_def png_struct;
+typedef PNG_CONST png_struct FAR * png_const_structp;
+typedef png_struct FAR * png_structp;
+
+/* These are the function types for the I/O functions and for the functions
+ * that allow the user to override the default I/O functions with his or her
+ * own.  The png_error_ptr type should match that of user-supplied warning
+ * and error functions, while the png_rw_ptr type should match that of the
+ * user read/write data functions.  Note that the 'write' function must not
+ * modify the buffer it is passed. The 'read' function, on the other hand, is
+ * expected to return the read data in the buffer.
+ */
+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));
+
+#ifdef PNG_PROGRESSIVE_READ_SUPPORTED
+typedef PNG_CALLBACK(void, *png_progressive_info_ptr, (png_structp, png_infop));
+typedef PNG_CALLBACK(void, *png_progressive_end_ptr, (png_structp, png_infop));
+
+/* The following callback receives png_uint_32 row_number, int pass for the
+ * png_bytep data of the row.  When transforming an interlaced image the
+ * row number is the row number within the sub-image of the interlace pass, so
+ * the value will increase to the height of the sub-image (not the full image)
+ * then reset to 0 for the next pass.
+ *
+ * Use PNG_ROW_FROM_PASS_ROW(row, pass) and PNG_COL_FROM_PASS_COL(col, pass) to
+ * find the output pixel (x,y) given an interlaced sub-image pixel
+ * (row,col,pass).  (See below for these macros.)
+ */
+typedef PNG_CALLBACK(void, *png_progressive_row_ptr, (png_structp, png_bytep,
+    png_uint_32, int));
+#endif
+
+#if defined(PNG_READ_USER_TRANSFORM_SUPPORTED) || \
+    defined(PNG_WRITE_USER_TRANSFORM_SUPPORTED)
+typedef PNG_CALLBACK(void, *png_user_transform_ptr, (png_structp, png_row_infop,
+    png_bytep));
+#endif
+
+#ifdef PNG_USER_CHUNKS_SUPPORTED
+typedef PNG_CALLBACK(int, *png_user_chunk_ptr, (png_structp,
+    png_unknown_chunkp));
+#endif
+#ifdef PNG_UNKNOWN_CHUNKS_SUPPORTED
+typedef PNG_CALLBACK(void, *png_unknown_chunk_ptr, (png_structp));
+#endif
+
+#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 of jmp_buf.  The
+ * function is required to be PNG_NORETURN, but this is not checked.  If the
+ * function does return the application will crash via an abort() or similar
+ * system level call.
+ *
+ * If you get a warning here while building the library you may 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!
+ */
+PNG_FUNCTION(void, (PNGCAPI *png_longjmp_ptr), PNGARG((jmp_buf, int)), typedef);
+#endif
+
+/* Transform masks for the high-level interface */
+#define PNG_TRANSFORM_IDENTITY       0x0000    /* read and write */
+#define PNG_TRANSFORM_STRIP_16       0x0001    /* read only */
+#define PNG_TRANSFORM_STRIP_ALPHA    0x0002    /* read only */
+#define PNG_TRANSFORM_PACKING        0x0004    /* read and write */
+#define PNG_TRANSFORM_PACKSWAP       0x0008    /* read and write */
+#define PNG_TRANSFORM_EXPAND         0x0010    /* read only */
+#define PNG_TRANSFORM_INVERT_MONO    0x0020    /* read and write */
+#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 */
+#define PNG_TRANSFORM_SWAP_ENDIAN    0x0200    /* read and write */
+#define PNG_TRANSFORM_INVERT_ALPHA   0x0400    /* read and write */
+#define PNG_TRANSFORM_STRIP_FILLER   0x0800    /* write only */
+/* Added to libpng-1.2.34 */
+#define PNG_TRANSFORM_STRIP_FILLER_BEFORE PNG_TRANSFORM_STRIP_FILLER
+#define PNG_TRANSFORM_STRIP_FILLER_AFTER 0x1000 /* write only */
+/* Added to libpng-1.4.0 */
+#define PNG_TRANSFORM_GRAY_TO_RGB   0x2000      /* read only */
+/* Added to libpng-1.5.4 */
+#define PNG_TRANSFORM_EXPAND_16     0x4000      /* read only */
+#define PNG_TRANSFORM_SCALE_16      0x8000      /* read only */
+
+/* Flags for MNG supported features */
+#define PNG_FLAG_MNG_EMPTY_PLTE     0x01
+#define PNG_FLAG_MNG_FILTER_64      0x04
+#define PNG_ALL_MNG_FEATURES        0x05
+
+/* 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));
+
+typedef png_struct FAR * FAR * png_structpp;
+
+/* Section 3: exported functions
+ * Here are the function definitions most commonly used.  This is not
+ * the place to find out how to use libpng.  See libpng-manual.txt for the
+ * full explanation, see example.c for the summary.  This just provides
+ * a simple one line description of the use of each function.
+ *
+ * The PNG_EXPORT() and PNG_EXPORTA() macros used below are defined in
+ * pngconf.h and in the *.dfn files in the scripts directory.
+ *
+ *   PNG_EXPORT(ordinal, type, name, (args));
+ *
+ *       ordinal:    ordinal that is used while building
+ *                   *.def files. The ordinal value is only
+ *                   relevant when preprocessing png.h with
+ *                   the *.dfn files for building symbol table
+ *                   entries, and are removed by pngconf.h.
+ *       type:       return type of the function
+ *       name:       function name
+ *       args:       function arguments, with types
+ *
+ * When we wish to append attributes to a function prototype we use
+ * the PNG_EXPORTA() macro instead.
+ *
+ *   PNG_EXPORTA(ordinal, type, name, (args), attributes);
+ *
+ *       ordinal, type, name, and args: same as in PNG_EXPORT().
+ *       attributes: function attributes
+ */
+
+/* Returns the version number of the library */
+PNG_EXPORT(1, png_uint_32, png_access_version_number, (void));
+
+/* Tell lib we have already handled the first <num_bytes> magic bytes.
+ * Handling more than 8 bytes from the beginning of the file is an error.
+ */
+PNG_EXPORT(2, void, png_set_sig_bytes, (png_structp png_ptr, int num_bytes));
+
+/* 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).
+ */
+PNG_EXPORT(3, int, png_sig_cmp, (png_const_bytep sig, png_size_t start,
+    png_size_t num_to_check));
+
+/* 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))
+
+/* Allocate and initialize png_ptr struct for reading, and any other memory. */
+PNG_EXPORTA(4, 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);
+
+/* Allocate and initialize png_ptr struct for writing, and any other memory */
+PNG_EXPORTA(5, 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);
+
+PNG_EXPORT(6, png_size_t, png_get_compression_buffer_size,
+    (png_const_structp png_ptr));
+
+PNG_EXPORT(7, void, png_set_compression_buffer_size, (png_structp png_ptr,
+    png_size_t size));
+
+/* 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.
+ */
+PNG_EXPORT(8, jmp_buf*, png_set_longjmp_fn, (png_structp png_ptr,
+    png_longjmp_ptr longjmp_fn, size_t jmp_buf_size));
+#  define png_jmpbuf(png_ptr) \
+      (*png_set_longjmp_fn((png_ptr), longjmp, sizeof (jmp_buf)))
+#else
+#  define png_jmpbuf(png_ptr) \
+      (LIBPNG_WAS_COMPILED_WITH__PNG_NO_SETJMP)
+#endif
+/* 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.
+ */
+PNG_EXPORTA(9, void, png_longjmp, (png_structp png_ptr, int val),
+    PNG_NORETURN);
+
+#ifdef PNG_READ_SUPPORTED
+/* Reset the compression stream */
+PNG_EXPORT(10, int, png_reset_zstream, (png_structp png_ptr));
+#endif
+
+/* New functions added in libpng-1.0.2 (not enabled by default until 1.2.0) */
+#ifdef PNG_USER_MEM_SUPPORTED
+PNG_EXPORTA(11, 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);
+PNG_EXPORTA(12, 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);
+#endif
+
+/* Write the PNG file signature. */
+PNG_EXPORT(13, void, png_write_sig, (png_structp png_ptr));
+
+/* Write a PNG chunk - size, type, (optional) data, CRC. */
+PNG_EXPORT(14, void, png_write_chunk, (png_structp png_ptr, png_const_bytep
+    chunk_name, png_const_bytep data, png_size_t length));
+
+/* Write the start of a PNG chunk - length and chunk name. */
+PNG_EXPORT(15, void, png_write_chunk_start, (png_structp png_ptr,
+    png_const_bytep chunk_name, png_uint_32 length));
+
+/* Write the data of a PNG chunk started with png_write_chunk_start(). */
+PNG_EXPORT(16, void, png_write_chunk_data, (png_structp png_ptr,
+    png_const_bytep data, png_size_t length));
+
+/* Finish a chunk started with png_write_chunk_start() (includes CRC). */
+PNG_EXPORT(17, void, png_write_chunk_end, (png_structp png_ptr));
+
+/* Allocate and initialize the info structure */
+PNG_EXPORTA(18, png_infop, png_create_info_struct, (png_structp png_ptr),
+    PNG_ALLOCATED);
+
+PNG_EXPORT(19, void, png_info_init_3, (png_infopp info_ptr,
+    png_size_t png_info_struct_size));
+
+/* Writes all the PNG information before the image. */
+PNG_EXPORT(20, void, png_write_info_before_PLTE,
+    (png_structp png_ptr, png_infop info_ptr));
+PNG_EXPORT(21, void, png_write_info,
+    (png_structp png_ptr, png_infop info_ptr));
+
+#ifdef PNG_SEQUENTIAL_READ_SUPPORTED
+/* Read the information before the actual image data. */
+PNG_EXPORT(22, void, png_read_info,
+    (png_structp png_ptr, png_infop info_ptr));
+#endif
+
+#ifdef PNG_TIME_RFC1123_SUPPORTED
+PNG_EXPORT(23, png_const_charp, png_convert_to_rfc1123,
+    (png_structp png_ptr,
+    png_const_timep ptime));
+#endif
+
+#ifdef PNG_CONVERT_tIME_SUPPORTED
+/* Convert from a struct tm to png_time */
+PNG_EXPORT(24, void, png_convert_from_struct_tm, (png_timep ptime,
+    PNG_CONST struct tm FAR * ttime));
+
+/* Convert from time_t to png_time.  Uses gmtime() */
+PNG_EXPORT(25, void, png_convert_from_time_t,
+    (png_timep ptime, time_t ttime));
+#endif /* PNG_CONVERT_tIME_SUPPORTED */
+
+#ifdef PNG_READ_EXPAND_SUPPORTED
+/* Expand data to 24-bit RGB, or 8-bit grayscale, with alpha if available. */
+PNG_EXPORT(26, void, png_set_expand, (png_structp png_ptr));
+PNG_EXPORT(27, void, png_set_expand_gray_1_2_4_to_8, (png_structp png_ptr));
+PNG_EXPORT(28, void, png_set_palette_to_rgb, (png_structp png_ptr));
+PNG_EXPORT(29, void, png_set_tRNS_to_alpha, (png_structp png_ptr));
+#endif
+
+#ifdef PNG_READ_EXPAND_16_SUPPORTED
+/* Expand to 16-bit channels, forces conversion of palette to RGB and expansion
+ * of a tRNS chunk if present.
+ */
+PNG_EXPORT(221, void, png_set_expand_16, (png_structp png_ptr));
+#endif
+
+#if defined(PNG_READ_BGR_SUPPORTED) || defined(PNG_WRITE_BGR_SUPPORTED)
+/* Use blue, green, red order for pixels. */
+PNG_EXPORT(30, void, png_set_bgr, (png_structp png_ptr));
+#endif
+
+#ifdef PNG_READ_GRAY_TO_RGB_SUPPORTED
+/* Expand the grayscale to 24-bit RGB if necessary. */
+PNG_EXPORT(31, void, png_set_gray_to_rgb, (png_structp png_ptr));
+#endif
+
+#ifdef PNG_READ_RGB_TO_GRAY_SUPPORTED
+/* Reduce RGB to grayscale. */
+#define PNG_ERROR_ACTION_NONE  1
+#define PNG_ERROR_ACTION_WARN  2
+#define PNG_ERROR_ACTION_ERROR 3
+#define PNG_RGB_TO_GRAY_DEFAULT (-1)/*for red/green coefficients*/
+
+PNG_FP_EXPORT(32, void, png_set_rgb_to_gray, (png_structp png_ptr,
+    int error_action, double red, double green))
+PNG_FIXED_EXPORT(33, void, png_set_rgb_to_gray_fixed, (png_structp png_ptr,
+    int error_action, png_fixed_point red, png_fixed_point green))
+
+PNG_EXPORT(34, png_byte, png_get_rgb_to_gray_status, (png_const_structp
+    png_ptr));
+#endif
+
+#ifdef PNG_BUILD_GRAYSCALE_PALETTE_SUPPORTED
+PNG_EXPORT(35, void, png_build_grayscale_palette, (int bit_depth,
+    png_colorp palette));
+#endif
+
+#ifdef PNG_READ_ALPHA_MODE_SUPPORTED
+/* How the alpha channel is interpreted - this affects how the color channels of
+ * a PNG file are returned when an alpha channel, or tRNS chunk in a palette
+ * file, is present.
+ *
+ * This has no effect on the way pixels are written into a PNG output
+ * datastream. The color samples in a PNG datastream are never premultiplied
+ * with the alpha samples.
+ *
+ * The default is to return data according to the PNG specification: the alpha
+ * channel is a linear measure of the contribution of the pixel to the
+ * corresponding composited pixel.  The gamma encoded color channels must be
+ * scaled according to the contribution and to do this it is necessary to undo
+ * the encoding, scale the color values, perform the composition and reencode
+ * the values.  This is the 'PNG' mode.
+ *
+ * The alternative is to 'associate' the alpha with the color information by
+ * storing color channel values that have been scaled by the alpha.  The
+ * advantage is that the color channels can be resampled (the image can be
+ * scaled) in this form.  The disadvantage is that normal practice is to store
+ * linear, not (gamma) encoded, values and this requires 16-bit channels for
+ * still images rather than the 8-bit channels that are just about sufficient if
+ * gamma encoding is used.  In addition all non-transparent pixel values,
+ * including completely opaque ones, must be gamma encoded to produce the final
+ * image.  This is the 'STANDARD', 'ASSOCIATED' or 'PREMULTIPLIED' mode (the
+ * latter being the two common names for associated alpha color channels.)
+ *
+ * Since it is not necessary to perform arithmetic on opaque color values so
+ * long as they are not to be resampled and are in the final color space it is
+ * possible to optimize the handling of alpha by storing the opaque pixels in
+ * the PNG format (adjusted for the output color space) while storing partially
+ * opaque pixels in the standard, linear, format.  The accuracy required for
+ * standard alpha composition is relatively low, because the pixels are
+ * isolated, therefore typically the accuracy loss in storing 8-bit linear
+ * values is acceptable.  (This is not true if the alpha channel is used to
+ * simulate transparency over large areas - use 16 bits or the PNG mode in
+ * this case!)  This is the 'OPTIMIZED' mode.  For this mode a pixel is
+ * treated as opaque only if the alpha value is equal to the maximum value.
+ *
+ * The final choice is to gamma encode the alpha channel as well.  This is
+ * broken because, in practice, no implementation that uses this choice
+ * correctly undoes the encoding before handling alpha composition.  Use this
+ * choice only if other serious errors in the software or hardware you use
+ * mandate it; the typical serious error is for dark halos to appear around
+ * opaque areas of the composited PNG image because of arithmetic overflow.
+ *
+ * The API function png_set_alpha_mode specifies which of these choices to use
+ * with an enumerated 'mode' value and the gamma of the required output:
+ */
+#define PNG_ALPHA_PNG           0 /* according to the PNG standard */
+#define PNG_ALPHA_STANDARD      1 /* according to Porter/Duff */
+#define PNG_ALPHA_ASSOCIATED    1 /* as above; this is the normal practice */
+#define PNG_ALPHA_PREMULTIPLIED 1 /* as above */
+#define PNG_ALPHA_OPTIMIZED     2 /* 'PNG' for opaque pixels, else 'STANDARD' */
+#define PNG_ALPHA_BROKEN        3 /* the alpha channel is gamma encoded */
+
+PNG_FP_EXPORT(227, void, png_set_alpha_mode, (png_structp png_ptr, int mode,
+    double output_gamma))
+PNG_FIXED_EXPORT(228, void, png_set_alpha_mode_fixed, (png_structp png_ptr,
+    int mode, png_fixed_point output_gamma))
+#endif
+
+#if defined(PNG_READ_GAMMA_SUPPORTED) || defined(PNG_READ_ALPHA_MODE_SUPPORTED)
+/* The output_gamma value is a screen gamma in libpng terminology: it expresses
+ * how to decode the output values, not how they are encoded.  The values used
+ * correspond to the normal numbers used to describe the overall gamma of a
+ * computer display system; for example 2.2 for an sRGB conformant system.  The
+ * values are scaled by 100000 in the _fixed version of the API (so 220000 for
+ * sRGB.)
+ *
+ * The inverse of the value is always used to provide a default for the PNG file
+ * encoding if it has no gAMA chunk and if png_set_gamma() has not been called
+ * to override the PNG gamma information.
+ *
+ * When the ALPHA_OPTIMIZED mode is selected the output gamma is used to encode
+ * opaque pixels however pixels with lower alpha values are not encoded,
+ * regardless of the output gamma setting.
+ *
+ * When the standard Porter Duff handling is requested with mode 1 the output
+ * encoding is set to be linear and the output_gamma value is only relevant
+ * as a default for input data that has no gamma information.  The linear output
+ * encoding will be overridden if png_set_gamma() is called - the results may be
+ * highly unexpected!
+ *
+ * The following numbers are derived from the sRGB standard and the research
+ * behind it.  sRGB is defined to be approximated by a PNG gAMA chunk value of
+ * 0.45455 (1/2.2) for PNG.  The value implicitly includes any viewing
+ * correction required to take account of any differences in the color
+ * environment of the original scene and the intended display environment; the
+ * value expresses how to *decode* the image for display, not how the original
+ * data was *encoded*.
+ *
+ * sRGB provides a peg for the PNG standard by defining a viewing environment.
+ * sRGB itself, and earlier TV standards, actually use a more complex transform
+ * (a linear portion then a gamma 2.4 power law) than PNG can express.  (PNG is
+ * limited to simple power laws.)  By saying that an image for direct display on
+ * an sRGB conformant system should be stored with a gAMA chunk value of 45455
+ * (11.3.3.2 and 11.3.3.5 of the ISO PNG specification) the PNG specification
+ * makes it possible to derive values for other display systems and
+ * environments.
+ *
+ * The Mac value is deduced from the sRGB based on an assumption that the actual
+ * extra viewing correction used in early Mac display systems was implemented as
+ * a power 1.45 lookup table.
+ *
+ * Any system where a programmable lookup table is used or where the behavior of
+ * the final display device characteristics can be changed requires system
+ * specific code to obtain the current characteristic.  However this can be
+ * difficult and most PNG gamma correction only requires an approximate value.
+ *
+ * By default, if png_set_alpha_mode() is not called, libpng assumes that all
+ * values are unencoded, linear, values and that the output device also has a
+ * linear characteristic.  This is only very rarely correct - it is invariably
+ * better to call png_set_alpha_mode() with PNG_DEFAULT_sRGB than rely on the
+ * default if you don't know what the right answer is!
+ *
+ * The special value PNG_GAMMA_MAC_18 indicates an older Mac system (pre Mac OS
+ * 10.6) which used a correction table to implement a somewhat lower gamma on an
+ * otherwise sRGB system.
+ *
+ * Both these values are reserved (not simple gamma values) in order to allow
+ * more precise correction internally in the future.
+ *
+ * NOTE: the following values can be passed to either the fixed or floating
+ * point APIs, but the floating point API will also accept floating point
+ * values.
+ */
+#define PNG_DEFAULT_sRGB -1       /* sRGB gamma and color space */
+#define PNG_GAMMA_MAC_18 -2       /* Old Mac '1.8' gamma and color space */
+#define PNG_GAMMA_sRGB   220000   /* Television standards--matches sRGB gamma */
+#define PNG_GAMMA_LINEAR PNG_FP_1 /* Linear */
+#endif
+
+/* The following are examples of calls to png_set_alpha_mode to achieve the
+ * required overall gamma correction and, where necessary, alpha
+ * premultiplication.
+ *
+ * png_set_alpha_mode(pp, PNG_ALPHA_PNG, PNG_DEFAULT_sRGB);
+ *    This is the default libpng handling of the alpha channel - it is not
+ *    pre-multiplied into the color components.  In addition the call states
+ *    that the output is for a sRGB system and causes all PNG files without gAMA
+ *    chunks to be assumed to be encoded using sRGB.
+ *
+ * png_set_alpha_mode(pp, PNG_ALPHA_PNG, PNG_GAMMA_MAC);
+ *    In this case the output is assumed to be something like an sRGB conformant
+ *    display preceeded by a power-law lookup table of power 1.45.  This is how
+ *    early Mac systems behaved.
+ *
+ * png_set_alpha_mode(pp, PNG_ALPHA_STANDARD, PNG_GAMMA_LINEAR);
+ *    This is the classic Jim Blinn approach and will work in academic
+ *    environments where everything is done by the book.  It has the shortcoming
+ *    of assuming that input PNG data with no gamma information is linear - this
+ *    is unlikely to be correct unless the PNG files where generated locally.
+ *    Most of the time the output precision will be so low as to show
+ *    significant banding in dark areas of the image.
+ *
+ * png_set_expand_16(pp);
+ * png_set_alpha_mode(pp, PNG_ALPHA_STANDARD, PNG_DEFAULT_sRGB);
+ *    This is a somewhat more realistic Jim Blinn inspired approach.  PNG files
+ *    are assumed to have the sRGB encoding if not marked with a gamma value and
+ *    the output is always 16 bits per component.  This permits accurate scaling
+ *    and processing of the data.  If you know that your input PNG files were
+ *    generated locally you might need to replace PNG_DEFAULT_sRGB with the
+ *    correct value for your system.
+ *
+ * png_set_alpha_mode(pp, PNG_ALPHA_OPTIMIZED, PNG_DEFAULT_sRGB);
+ *    If you just need to composite the PNG image onto an existing background
+ *    and if you control the code that does this you can use the optimization
+ *    setting.  In this case you just copy completely opaque pixels to the
+ *    output.  For pixels that are not completely transparent (you just skip
+ *    those) you do the composition math using png_composite or png_composite_16
+ *    below then encode the resultant 8-bit or 16-bit values to match the output
+ *    encoding.
+ *
+ * Other cases
+ *    If neither the PNG nor the standard linear encoding work for you because
+ *    of the software or hardware you use then you have a big problem.  The PNG
+ *    case will probably result in halos around the image.  The linear encoding
+ *    will probably result in a washed out, too bright, image (it's actually too
+ *    contrasty.)  Try the ALPHA_OPTIMIZED mode above - this will probably
+ *    substantially reduce the halos.  Alternatively try:
+ *
+ * png_set_alpha_mode(pp, PNG_ALPHA_BROKEN, PNG_DEFAULT_sRGB);
+ *    This option will also reduce the halos, but there will be slight dark
+ *    halos round the opaque parts of the image where the background is light.
+ *    In the OPTIMIZED mode the halos will be light halos where the background
+ *    is dark.  Take your pick - the halos are unavoidable unless you can get
+ *    your hardware/software fixed!  (The OPTIMIZED approach is slightly
+ *    faster.)
+ *
+ * When the default gamma of PNG files doesn't match the output gamma.
+ *    If you have PNG files with no gamma information png_set_alpha_mode allows
+ *    you to provide a default gamma, but it also sets the ouput gamma to the
+ *    matching value.  If you know your PNG files have a gamma that doesn't
+ *    match the output you can take advantage of the fact that
+ *    png_set_alpha_mode always sets the output gamma but only sets the PNG
+ *    default if it is not already set:
+ *
+ * png_set_alpha_mode(pp, PNG_ALPHA_PNG, PNG_DEFAULT_sRGB);
+ * png_set_alpha_mode(pp, PNG_ALPHA_PNG, PNG_GAMMA_MAC);
+ *    The first call sets both the default and the output gamma values, the
+ *    second call overrides the output gamma without changing the default.  This
+ *    is easier than achieving the same effect with png_set_gamma.  You must use
+ *    PNG_ALPHA_PNG for the first call - internal checking in png_set_alpha will
+ *    fire if more than one call to png_set_alpha_mode and png_set_background is
+ *    made in the same read operation, however multiple calls with PNG_ALPHA_PNG
+ *    are ignored.
+ */
+
+#ifdef PNG_READ_STRIP_ALPHA_SUPPORTED
+PNG_EXPORT(36, void, png_set_strip_alpha, (png_structp png_ptr));
+#endif
+
+#if defined(PNG_READ_SWAP_ALPHA_SUPPORTED) || \
+    defined(PNG_WRITE_SWAP_ALPHA_SUPPORTED)
+PNG_EXPORT(37, void, png_set_swap_alpha, (png_structp png_ptr));
+#endif
+
+#if defined(PNG_READ_INVERT_ALPHA_SUPPORTED) || \
+    defined(PNG_WRITE_INVERT_ALPHA_SUPPORTED)
+PNG_EXPORT(38, void, png_set_invert_alpha, (png_structp png_ptr));
+#endif
+
+#if defined(PNG_READ_FILLER_SUPPORTED) || defined(PNG_WRITE_FILLER_SUPPORTED)
+/* Add a filler byte to 8-bit Gray or 24-bit RGB images. */
+PNG_EXPORT(39, void, png_set_filler, (png_structp png_ptr, png_uint_32 filler,
+    int flags));
+/* The values of the PNG_FILLER_ defines should NOT be changed */
+#  define PNG_FILLER_BEFORE 0
+#  define PNG_FILLER_AFTER 1
+/* Add an alpha byte to 8-bit Gray or 24-bit RGB images. */
+PNG_EXPORT(40, void, png_set_add_alpha,
+    (png_structp png_ptr, png_uint_32 filler,
+    int flags));
+#endif /* PNG_READ_FILLER_SUPPORTED || PNG_WRITE_FILLER_SUPPORTED */
+
+#if defined(PNG_READ_SWAP_SUPPORTED) || defined(PNG_WRITE_SWAP_SUPPORTED)
+/* Swap bytes in 16-bit depth files. */
+PNG_EXPORT(41, void, png_set_swap, (png_structp png_ptr));
+#endif
+
+#if defined(PNG_READ_PACK_SUPPORTED) || defined(PNG_WRITE_PACK_SUPPORTED)
+/* Use 1 byte per pixel in 1, 2, or 4-bit depth files. */
+PNG_EXPORT(42, void, png_set_packing, (png_structp png_ptr));
+#endif
+
+#if defined(PNG_READ_PACKSWAP_SUPPORTED) || \
+    defined(PNG_WRITE_PACKSWAP_SUPPORTED)
+/* Swap packing order of pixels in bytes. */
+PNG_EXPORT(43, void, png_set_packswap, (png_structp png_ptr));
+#endif
+
+#if defined(PNG_READ_SHIFT_SUPPORTED) || defined(PNG_WRITE_SHIFT_SUPPORTED)
+/* Converts files to legal bit depths. */
+PNG_EXPORT(44, void, png_set_shift, (png_structp png_ptr, png_const_color_8p
+    true_bits));
+#endif
+
+#if defined(PNG_READ_INTERLACING_SUPPORTED) || \
+    defined(PNG_WRITE_INTERLACING_SUPPORTED)
+/* 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.
+*/
+PNG_EXPORT(45, int, png_set_interlace_handling, (png_structp png_ptr));
+#endif
+
+#if defined(PNG_READ_INVERT_SUPPORTED) || defined(PNG_WRITE_INVERT_SUPPORTED)
+/* Invert monochrome files */
+PNG_EXPORT(46, void, png_set_invert_mono, (png_structp png_ptr));
+#endif
+
+#ifdef PNG_READ_BACKGROUND_SUPPORTED
+/* Handle alpha and tRNS by replacing with a background color.  Prior to
+ * libpng-1.5.4 this API must not be called before the PNG file header has been
+ * read.  Doing so will result in unexpected behavior and possible warnings or
+ * errors if the PNG file contains a bKGD chunk.
+ */
+PNG_FP_EXPORT(47, void, png_set_background, (png_structp png_ptr,
+    png_const_color_16p background_color, int background_gamma_code,
+    int need_expand, double background_gamma))
+PNG_FIXED_EXPORT(215, void, png_set_background_fixed, (png_structp png_ptr,
+    png_const_color_16p background_color, int background_gamma_code,
+    int need_expand, png_fixed_point background_gamma))
+#endif
+#ifdef PNG_READ_BACKGROUND_SUPPORTED
+#  define PNG_BACKGROUND_GAMMA_UNKNOWN 0
+#  define PNG_BACKGROUND_GAMMA_SCREEN  1
+#  define PNG_BACKGROUND_GAMMA_FILE    2
+#  define PNG_BACKGROUND_GAMMA_UNIQUE  3
+#endif
+
+#ifdef PNG_READ_SCALE_16_TO_8_SUPPORTED
+/* Scale a 16-bit depth file down to 8-bit, accurately. */
+PNG_EXPORT(229, void, png_set_scale_16, (png_structp png_ptr));
+#endif
+
+#ifdef PNG_READ_STRIP_16_TO_8_SUPPORTED
+#define PNG_READ_16_TO_8 SUPPORTED /* Name prior to 1.5.4 */
+/* Strip the second byte of information from a 16-bit depth file. */
+PNG_EXPORT(48, void, png_set_strip_16, (png_structp png_ptr));
+#endif
+
+#ifdef PNG_READ_QUANTIZE_SUPPORTED
+/* Turn on quantizing, and reduce the palette to the number of colors
+ * available.
+ */
+PNG_EXPORT(49, void, png_set_quantize,
+    (png_structp png_ptr, png_colorp palette,
+    int num_palette, int maximum_colors, png_const_uint_16p histogram,
+    int full_quantize));
+#endif
+
+#ifdef PNG_READ_GAMMA_SUPPORTED
+/* 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)
+
+/* Handle gamma correction. Screen_gamma=(display_exponent).
+ * NOTE: this API simply sets the screen and file gamma values. It will
+ * therefore override the value for gamma in a PNG file if it is called after
+ * the file header has been read - use with care  - call before reading the PNG
+ * file for best results!
+ *
+ * These routines accept the same gamma values as png_set_alpha_mode (described
+ * above).  The PNG_GAMMA_ defines and PNG_DEFAULT_sRGB can be passed to either
+ * API (floating point or fixed.)  Notice, however, that the 'file_gamma' value
+ * is the inverse of a 'screen gamma' value.
+ */
+PNG_FP_EXPORT(50, void, png_set_gamma,
+    (png_structp png_ptr, double screen_gamma,
+    double override_file_gamma))
+PNG_FIXED_EXPORT(208, void, png_set_gamma_fixed, (png_structp png_ptr,
+    png_fixed_point screen_gamma, png_fixed_point override_file_gamma))
+#endif
+
+#ifdef PNG_WRITE_FLUSH_SUPPORTED
+/* Set how many lines between output flushes - 0 for no flushing */
+PNG_EXPORT(51, void, png_set_flush, (png_structp png_ptr, int nrows));
+/* Flush the current PNG output buffer */
+PNG_EXPORT(52, void, png_write_flush, (png_structp png_ptr));
+#endif
+
+/* Optional update palette with requested transformations */
+PNG_EXPORT(53, void, png_start_read_image, (png_structp png_ptr));
+
+/* Optional call to update the users info structure */
+PNG_EXPORT(54, void, png_read_update_info,
+    (png_structp png_ptr, png_infop info_ptr));
+
+#ifdef PNG_SEQUENTIAL_READ_SUPPORTED
+/* Read one or more rows of image data. */
+PNG_EXPORT(55, void, png_read_rows, (png_structp png_ptr, png_bytepp row,
+    png_bytepp display_row, png_uint_32 num_rows));
+#endif
+
+#ifdef PNG_SEQUENTIAL_READ_SUPPORTED
+/* Read a row of data. */
+PNG_EXPORT(56, void, png_read_row, (png_structp png_ptr, png_bytep row,
+    png_bytep display_row));
+#endif
+
+#ifdef PNG_SEQUENTIAL_READ_SUPPORTED
+/* Read the whole image into memory at once. */
+PNG_EXPORT(57, void, png_read_image, (png_structp png_ptr, png_bytepp image));
+#endif
+
+/* Write a row of image data */
+PNG_EXPORT(58, void, png_write_row,
+    (png_structp png_ptr, png_const_bytep row));
+
+/* Write a few rows of image data: (*row) is not written; however, the type
+ * is 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.
+ */
+PNG_EXPORT(59, void, png_write_rows, (png_structp png_ptr, png_bytepp row,
+    png_uint_32 num_rows));
+
+/* Write the image data */
+PNG_EXPORT(60, void, png_write_image,
+    (png_structp png_ptr, png_bytepp image));
+
+/* Write the end of the PNG file. */
+PNG_EXPORT(61, void, png_write_end,
+    (png_structp png_ptr, png_infop info_ptr));
+
+#ifdef PNG_SEQUENTIAL_READ_SUPPORTED
+/* Read the end of the PNG file. */
+PNG_EXPORT(62, void, png_read_end, (png_structp png_ptr, png_infop info_ptr));
+#endif
+
+/* Free any memory associated with the png_info_struct */
+PNG_EXPORT(63, void, png_destroy_info_struct, (png_structp png_ptr,
+    png_infopp info_ptr_ptr));
+
+/* Free any memory associated with the png_struct and the png_info_structs */
+PNG_EXPORT(64, void, png_destroy_read_struct, (png_structpp png_ptr_ptr,
+    png_infopp info_ptr_ptr, png_infopp end_info_ptr_ptr));
+
+/* Free any memory associated with the png_struct and the png_info_structs */
+PNG_EXPORT(65, void, png_destroy_write_struct, (png_structpp png_ptr_ptr,
+    png_infopp info_ptr_ptr));
+
+/* Set the libpng method of handling chunk CRC errors */
+PNG_EXPORT(66, void, png_set_crc_action,
+    (png_structp png_ptr, int crit_action, int ancil_action));
+
+/* Values for png_set_crc_action() say how to handle CRC errors in
+ * 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
+ */
+#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 */
+
+/* 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
+ * header file (zlib.h) for an explination of the compression functions.
+ */
+
+/* Set the filtering method(s) used by libpng.  Currently, the only valid
+ * value for "method" is 0.
+ */
+PNG_EXPORT(67, void, png_set_filter,
+    (png_structp png_ptr, int method, int filters));
+
+/* Flags for png_set_filter() to say which filters to use.  The flags
+ * 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.
+ */
+#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)
+
+/* 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
+
+#ifdef PNG_WRITE_WEIGHTED_FILTER_SUPPORTED /* EXPERIMENTAL */
+/* 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.
+ */
+PNG_FP_EXPORT(68, void, png_set_filter_heuristics, (png_structp png_ptr,
+    int heuristic_method, int num_weights, png_const_doublep filter_weights,
+    png_const_doublep filter_costs))
+PNG_FIXED_EXPORT(209, void, png_set_filter_heuristics_fixed,
+    (png_structp png_ptr,
+    int heuristic_method, int num_weights, png_const_fixed_point_p
+    filter_weights, png_const_fixed_point_p filter_costs))
+#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 */
+
+#ifdef PNG_WRITE_SUPPORTED
+/* 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.
+ */
+PNG_EXPORT(69, void, png_set_compression_level,
+    (png_structp png_ptr, int level));
+
+PNG_EXPORT(70, void, png_set_compression_mem_level, (png_structp png_ptr,
+    int mem_level));
+
+PNG_EXPORT(71, void, png_set_compression_strategy, (png_structp png_ptr,
+    int strategy));
+
+/* If PNG_WRITE_OPTIMIZE_CMF_SUPPORTED is defined, libpng will use a
+ * smaller value of window_bits if it can do so safely.
+ */
+PNG_EXPORT(72, void, png_set_compression_window_bits, (png_structp png_ptr,
+    int window_bits));
+
+PNG_EXPORT(73, void, png_set_compression_method, (png_structp png_ptr,
+    int method));
+#endif
+
+#ifdef PNG_WRITE_CUSTOMIZE_ZTXT_COMPRESSION_SUPPORTED
+/* Also set zlib parameters for compressing non-IDAT chunks */
+PNG_EXPORT(222, void, png_set_text_compression_level,
+    (png_structp png_ptr, int level));
+
+PNG_EXPORT(223, void, png_set_text_compression_mem_level, (png_structp png_ptr,
+    int mem_level));
+
+PNG_EXPORT(224, void, png_set_text_compression_strategy, (png_structp png_ptr,
+    int strategy));
+
+/* If PNG_WRITE_OPTIMIZE_CMF_SUPPORTED is defined, libpng will use a
+ * smaller value of window_bits if it can do so safely.
+ */
+PNG_EXPORT(225, void, png_set_text_compression_window_bits, (png_structp
+    png_ptr, int window_bits));
+
+PNG_EXPORT(226, void, png_set_text_compression_method, (png_structp png_ptr,
+    int method));
+#endif /* PNG_WRITE_CUSTOMIZE_ZTXT_COMPRESSION_SUPPORTED */
+
+/* These next functions are called for input/output, memory, and error
+ * handling.  They are in the file pngrio.c, pngwio.c, and pngerror.c,
+ * and call standard C I/O routines such as fread(), fwrite(), and
+ * fprintf().  These functions can be made to use other I/O routines
+ * at run time for those applications that need to handle I/O in a
+ * different manner by calling png_set_???_fn().  See libpng-manual.txt for
+ * more information.
+ */
+
+#ifdef PNG_STDIO_SUPPORTED
+/* Initialize the input/output for the PNG file to the default functions. */
+PNG_EXPORT(74, void, png_init_io, (png_structp png_ptr, png_FILE_p fp));
+#endif
+
+/* Replace the (error and abort), and warning functions with user
+ * 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.
+ */
+
+PNG_EXPORT(75, void, png_set_error_fn,
+    (png_structp png_ptr, png_voidp error_ptr,
+    png_error_ptr error_fn, png_error_ptr warning_fn));
+
+/* Return the user pointer associated with the error functions */
+PNG_EXPORT(76, png_voidp, png_get_error_ptr, (png_const_structp png_ptr));
+
+/* Replace the default data output functions with a user supplied one(s).
+ * 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).
+ * 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.
+ */
+PNG_EXPORT(77, 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));
+
+/* Replace the default data input function with a user supplied one. */
+PNG_EXPORT(78, void, png_set_read_fn, (png_structp png_ptr, png_voidp io_ptr,
+    png_rw_ptr read_data_fn));
+
+/* Return the user pointer associated with the I/O functions */
+PNG_EXPORT(79, png_voidp, png_get_io_ptr, (png_structp png_ptr));
+
+PNG_EXPORT(80, void, png_set_read_status_fn, (png_structp png_ptr,
+    png_read_status_ptr read_row_fn));
+
+PNG_EXPORT(81, void, png_set_write_status_fn, (png_structp png_ptr,
+    png_write_status_ptr write_row_fn));
+
+#ifdef PNG_USER_MEM_SUPPORTED
+/* Replace the default memory allocation functions with user supplied one(s). */
+PNG_EXPORT(82, void, png_set_mem_fn, (png_structp png_ptr, png_voidp mem_ptr,
+    png_malloc_ptr malloc_fn, png_free_ptr free_fn));
+/* Return the user pointer associated with the memory functions */
+PNG_EXPORT(83, png_voidp, png_get_mem_ptr, (png_const_structp png_ptr));
+#endif
+
+#ifdef PNG_READ_USER_TRANSFORM_SUPPORTED
+PNG_EXPORT(84, void, png_set_read_user_transform_fn, (png_structp png_ptr,
+    png_user_transform_ptr read_user_transform_fn));
+#endif
+
+#ifdef PNG_WRITE_USER_TRANSFORM_SUPPORTED
+PNG_EXPORT(85, void, png_set_write_user_transform_fn, (png_structp png_ptr,
+    png_user_transform_ptr write_user_transform_fn));
+#endif
+
+#ifdef PNG_USER_TRANSFORM_PTR_SUPPORTED
+PNG_EXPORT(86, void, png_set_user_transform_info, (png_structp png_ptr,
+    png_voidp user_transform_ptr, int user_transform_depth,
+    int user_transform_channels));
+/* Return the user pointer associated with the user transform functions */
+PNG_EXPORT(87, png_voidp, png_get_user_transform_ptr,
+    (png_const_structp png_ptr));
+#endif
+
+#ifdef PNG_USER_TRANSFORM_INFO_SUPPORTED
+/* Return information about the row currently being processed.  Note that these
+ * APIs do not fail but will return unexpected results if called outside a user
+ * transform callback.  Also note that when transforming an interlaced image the
+ * row number is the row number within the sub-image of the interlace pass, so
+ * the value will increase to the height of the sub-image (not the full image)
+ * then reset to 0 for the next pass.
+ *
+ * Use PNG_ROW_FROM_PASS_ROW(row, pass) and PNG_COL_FROM_PASS_COL(col, pass) to
+ * find the output pixel (x,y) given an interlaced sub-image pixel
+ * (row,col,pass).  (See below for these macros.)
+ */
+PNG_EXPORT(217, png_uint_32, png_get_current_row_number, (png_const_structp));
+PNG_EXPORT(218, png_byte, png_get_current_pass_number, (png_const_structp));
+#endif
+
+#ifdef PNG_USER_CHUNKS_SUPPORTED
+PNG_EXPORT(88, void, png_set_read_user_chunk_fn, (png_structp png_ptr,
+    png_voidp user_chunk_ptr, png_user_chunk_ptr read_user_chunk_fn));
+PNG_EXPORT(89, png_voidp, png_get_user_chunk_ptr, (png_const_structp png_ptr));
+#endif
+
+#ifdef PNG_PROGRESSIVE_READ_SUPPORTED
+/* Sets the function callbacks for the push reader, and a pointer to a
+ * user-defined structure available to the callback functions.
+ */
+PNG_EXPORT(90, void, png_set_progressive_read_fn, (png_structp png_ptr,
+    png_voidp progressive_ptr, png_progressive_info_ptr info_fn,
+    png_progressive_row_ptr row_fn, png_progressive_end_ptr end_fn));
+
+/* Returns the user pointer associated with the push read functions */
+PNG_EXPORT(91, png_voidp, png_get_progressive_ptr, (png_const_structp png_ptr));
+
+/* Function to be called when data becomes available */
+PNG_EXPORT(92, void, png_process_data,
+    (png_structp png_ptr, png_infop info_ptr,
+    png_bytep buffer, png_size_t buffer_size));
+
+/* A function which may be called *only* within png_process_data to stop the
+ * processing of any more data.  The function returns the number of bytes
+ * remaining, excluding any that libpng has cached internally.  A subsequent
+ * call to png_process_data must supply these bytes again.  If the argument
+ * 'save' is set to true the routine will first save all the pending data and
+ * will always return 0.
+ */
+PNG_EXPORT(219, png_size_t, png_process_data_pause, (png_structp, int save));
+
+/* A function which may be called *only* outside (after) a call to
+ * png_process_data.  It returns the number of bytes of data to skip in the
+ * input.  Normally it will return 0, but if it returns a non-zero value the
+ * application must skip than number of bytes of input data and pass the
+ * following data to the next call to png_process_data.
+ */
+PNG_EXPORT(220, png_uint_32, png_process_data_skip, (png_structp));
+
+#ifdef PNG_READ_INTERLACING_SUPPORTED
+/* Function that combines rows.  'new_row' is a flag that should come from
+ * the callback and be non-NULL if anything needs to be done; the library
+ * stores its own version of the new data internally and ignores the passed
+ * in value.
+ */
+PNG_EXPORT(93, void, png_progressive_combine_row, (png_structp png_ptr,
+    png_bytep old_row, png_const_bytep new_row));
+#endif /* PNG_READ_INTERLACING_SUPPORTED */
+#endif /* PNG_PROGRESSIVE_READ_SUPPORTED */
+
+PNG_EXPORTA(94, png_voidp, png_malloc,
+    (png_structp png_ptr, png_alloc_size_t size),
+    PNG_ALLOCATED);
+/* Added at libpng version 1.4.0 */
+PNG_EXPORTA(95, png_voidp, png_calloc,
+    (png_structp png_ptr, png_alloc_size_t size),
+    PNG_ALLOCATED);
+
+/* Added at libpng version 1.2.4 */
+PNG_EXPORTA(96, png_voidp, png_malloc_warn, (png_structp png_ptr,
+    png_alloc_size_t size), PNG_ALLOCATED);
+
+/* Frees a pointer allocated by png_malloc() */
+PNG_EXPORT(97, void, png_free, (png_structp png_ptr, png_voidp ptr));
+
+/* Free data that was allocated internally */
+PNG_EXPORT(98, void, png_free_data,
+    (png_structp png_ptr, png_infop info_ptr, png_uint_32 free_me, int num));
+
+/* Reassign responsibility for freeing existing data, whether allocated
+ * by libpng or by the application */
+PNG_EXPORT(99, void, png_data_freer,
+    (png_structp png_ptr, png_infop info_ptr, int freer, png_uint_32 mask));
+
+/* Assignments for png_data_freer */
+#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 */
+#define PNG_FREE_HIST 0x0008
+#define PNG_FREE_ICCP 0x0010
+#define PNG_FREE_SPLT 0x0020
+#define PNG_FREE_ROWS 0x0040
+#define PNG_FREE_PCAL 0x0080
+#define PNG_FREE_SCAL 0x0100
+#define PNG_FREE_UNKN 0x0200
+#define PNG_FREE_LIST 0x0400
+#define PNG_FREE_PLTE 0x1000
+#define PNG_FREE_TRNS 0x2000
+#define PNG_FREE_TEXT 0x4000
+#define PNG_FREE_ALL  0x7fff
+#define PNG_FREE_MUL  0x4220 /* PNG_FREE_SPLT|PNG_FREE_TEXT|PNG_FREE_UNKN */
+
+#ifdef PNG_USER_MEM_SUPPORTED
+PNG_EXPORTA(100, png_voidp, png_malloc_default, (png_structp png_ptr,
+    png_alloc_size_t size), PNG_ALLOCATED);
+PNG_EXPORT(101, void, png_free_default, (png_structp png_ptr, png_voidp ptr));
+#endif
+
+#ifdef PNG_ERROR_TEXT_SUPPORTED
+/* Fatal error in PNG image of libpng - can't continue */
+PNG_EXPORTA(102, void, png_error,
+    (png_structp png_ptr, png_const_charp error_message),
+    PNG_NORETURN);
+
+/* The same, but the chunk name is prepended to the error string. */
+PNG_EXPORTA(103, void, png_chunk_error, (png_structp png_ptr,
+    png_const_charp error_message), PNG_NORETURN);
+
+#else
+/* Fatal error in PNG image of libpng - can't continue */
+PNG_EXPORTA(104, void, png_err, (png_structp png_ptr), PNG_NORETURN);
+#endif
+
+#ifdef PNG_WARNINGS_SUPPORTED
+/* Non-fatal error in libpng.  Can continue, but may have a problem. */
+PNG_EXPORT(105, void, png_warning, (png_structp png_ptr,
+    png_const_charp warning_message));
+
+/* Non-fatal error in libpng, chunk name is prepended to message. */
+PNG_EXPORT(106, void, png_chunk_warning, (png_structp png_ptr,
+    png_const_charp warning_message));
+#endif
+
+#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. */
+#  undef png_benign_error
+PNG_EXPORT(107, void, png_benign_error, (png_structp png_ptr,
+    png_const_charp warning_message));
+
+/* Same, chunk name is prepended to message. */
+#  undef png_chunk_benign_error
+PNG_EXPORT(108, void, png_chunk_benign_error, (png_structp png_ptr,
+    png_const_charp warning_message));
+
+PNG_EXPORT(109, void, png_set_benign_errors,
+    (png_structp png_ptr, int allowed));
+#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
+#endif
+
+/* 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.
+ */
+/* Returns "flag" if chunk data is valid in info_ptr. */
+PNG_EXPORT(110, png_uint_32, png_get_valid,
+    (png_const_structp png_ptr, png_const_infop info_ptr,
+    png_uint_32 flag));
+
+/* Returns number of bytes needed to hold a transformed row. */
+PNG_EXPORT(111, png_size_t, png_get_rowbytes, (png_const_structp png_ptr,
+    png_const_infop info_ptr));
+
+#ifdef PNG_INFO_IMAGE_SUPPORTED
+/* Returns row_pointers, which is an array of pointers to scanlines that was
+ * returned from png_read_png().
+ */
+PNG_EXPORT(112, png_bytepp, png_get_rows,
+    (png_const_structp png_ptr, png_const_infop info_ptr));
+/* Set row_pointers, which is an array of pointers to scanlines for use
+ * by png_write_png().
+ */
+PNG_EXPORT(113, void, png_set_rows, (png_structp png_ptr,
+    png_infop info_ptr, png_bytepp row_pointers));
+#endif
+
+/* Returns number of color channels in image. */
+PNG_EXPORT(114, png_byte, png_get_channels,
+    (png_const_structp png_ptr, png_const_infop info_ptr));
+
+#ifdef PNG_EASY_ACCESS_SUPPORTED
+/* Returns image width in pixels. */
+PNG_EXPORT(115, png_uint_32, png_get_image_width, (png_const_structp png_ptr,
+    png_const_infop info_ptr));
+
+/* Returns image height in pixels. */
+PNG_EXPORT(116, png_uint_32, png_get_image_height, (png_const_structp png_ptr,
+    png_const_infop info_ptr));
+
+/* Returns image bit_depth. */
+PNG_EXPORT(117, png_byte, png_get_bit_depth,
+    (png_const_structp png_ptr, png_const_infop info_ptr));
+
+/* Returns image color_type. */
+PNG_EXPORT(118, png_byte, png_get_color_type, (png_const_structp png_ptr,
+    png_const_infop info_ptr));
+
+/* Returns image filter_type. */
+PNG_EXPORT(119, png_byte, png_get_filter_type, (png_const_structp png_ptr,
+    png_const_infop info_ptr));
+
+/* Returns image interlace_type. */
+PNG_EXPORT(120, png_byte, png_get_interlace_type, (png_const_structp png_ptr,
+    png_const_infop info_ptr));
+
+/* Returns image compression_type. */
+PNG_EXPORT(121, png_byte, png_get_compression_type, (png_const_structp png_ptr,
+    png_const_infop info_ptr));
+
+/* Returns image resolution in pixels per meter, from pHYs chunk data. */
+PNG_EXPORT(122, png_uint_32, png_get_pixels_per_meter,
+    (png_const_structp png_ptr, png_const_infop info_ptr));
+PNG_EXPORT(123, png_uint_32, png_get_x_pixels_per_meter,
+    (png_const_structp png_ptr, png_const_infop info_ptr));
+PNG_EXPORT(124, png_uint_32, png_get_y_pixels_per_meter,
+    (png_const_structp png_ptr, png_const_infop info_ptr));
+
+/* Returns pixel aspect ratio, computed from pHYs chunk data.  */
+PNG_FP_EXPORT(125, float, png_get_pixel_aspect_ratio,
+    (png_const_structp png_ptr, png_const_infop info_ptr))
+PNG_FIXED_EXPORT(210, png_fixed_point, png_get_pixel_aspect_ratio_fixed,
+    (png_const_structp png_ptr, png_const_infop info_ptr))
+
+/* Returns image x, y offset in pixels or microns, from oFFs chunk data. */
+PNG_EXPORT(126, png_int_32, png_get_x_offset_pixels,
+    (png_const_structp png_ptr, png_const_infop info_ptr));
+PNG_EXPORT(127, png_int_32, png_get_y_offset_pixels,
+    (png_const_structp png_ptr, png_const_infop info_ptr));
+PNG_EXPORT(128, png_int_32, png_get_x_offset_microns,
+    (png_const_structp png_ptr, png_const_infop info_ptr));
+PNG_EXPORT(129, png_int_32, png_get_y_offset_microns,
+    (png_const_structp png_ptr, png_const_infop info_ptr));
+
+#endif /* PNG_EASY_ACCESS_SUPPORTED */
+
+/* Returns pointer to signature string read from PNG header */
+PNG_EXPORT(130, png_const_bytep, png_get_signature,
+    (png_const_structp png_ptr, png_infop info_ptr));
+
+#ifdef PNG_bKGD_SUPPORTED
+PNG_EXPORT(131, png_uint_32, png_get_bKGD,
+    (png_const_structp png_ptr, png_infop info_ptr,
+    png_color_16p *background));
+#endif
+
+#ifdef PNG_bKGD_SUPPORTED
+PNG_EXPORT(132, void, png_set_bKGD, (png_structp png_ptr, png_infop info_ptr,
+    png_const_color_16p background));
+#endif
+
+#ifdef PNG_cHRM_SUPPORTED
+PNG_FP_EXPORT(133, png_uint_32, png_get_cHRM, (png_const_structp png_ptr,
+   png_const_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))
+PNG_FP_EXPORT(230, png_uint_32, png_get_cHRM_XYZ, (png_structp png_ptr,
+    png_const_infop info_ptr, double *red_X, double *red_Y, double *red_Z,
+    double *green_X, double *green_Y, double *green_Z, double *blue_X,
+    double *blue_Y, double *blue_Z))
+#ifdef PNG_FIXED_POINT_SUPPORTED /* Otherwise not implemented */
+PNG_FIXED_EXPORT(134, png_uint_32, png_get_cHRM_fixed,
+    (png_const_structp png_ptr,
+    png_const_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))
+#endif
+PNG_FIXED_EXPORT(231, png_uint_32, png_get_cHRM_XYZ_fixed,
+    (png_structp png_ptr, png_const_infop info_ptr,
+    png_fixed_point *int_red_X, png_fixed_point *int_red_Y,
+    png_fixed_point *int_red_Z, png_fixed_point *int_green_X,
+    png_fixed_point *int_green_Y, png_fixed_point *int_green_Z,
+    png_fixed_point *int_blue_X, png_fixed_point *int_blue_Y,
+    png_fixed_point *int_blue_Z))
+#endif
+
+#ifdef PNG_cHRM_SUPPORTED
+PNG_FP_EXPORT(135, 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))
+PNG_FP_EXPORT(232, void, png_set_cHRM_XYZ, (png_structp png_ptr,
+    png_infop info_ptr, double red_X, double red_Y, double red_Z,
+    double green_X, double green_Y, double green_Z, double blue_X,
+    double blue_Y, double blue_Z))
+PNG_FIXED_EXPORT(136, 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))
+PNG_FIXED_EXPORT(233, void, png_set_cHRM_XYZ_fixed, (png_structp png_ptr,
+    png_infop info_ptr, png_fixed_point int_red_X, png_fixed_point int_red_Y,
+    png_fixed_point int_red_Z, png_fixed_point int_green_X,
+    png_fixed_point int_green_Y, png_fixed_point int_green_Z,
+    png_fixed_point int_blue_X, png_fixed_point int_blue_Y,
+    png_fixed_point int_blue_Z))
+#endif
+
+#ifdef PNG_gAMA_SUPPORTED
+PNG_FP_EXPORT(137, png_uint_32, png_get_gAMA,
+    (png_const_structp png_ptr, png_const_infop info_ptr,
+    double *file_gamma))
+PNG_FIXED_EXPORT(138, png_uint_32, png_get_gAMA_fixed,
+    (png_const_structp png_ptr, png_const_infop info_ptr,
+    png_fixed_point *int_file_gamma))
+#endif
+
+#ifdef PNG_gAMA_SUPPORTED
+PNG_FP_EXPORT(139, void, png_set_gAMA, (png_structp png_ptr,
+    png_infop info_ptr, double file_gamma))
+PNG_FIXED_EXPORT(140, void, png_set_gAMA_fixed, (png_structp png_ptr,
+    png_infop info_ptr, png_fixed_point int_file_gamma))
+#endif
+
+#ifdef PNG_hIST_SUPPORTED
+PNG_EXPORT(141, png_uint_32, png_get_hIST,
+    (png_const_structp png_ptr, png_const_infop info_ptr,
+    png_uint_16p *hist));
+#endif
+
+#ifdef PNG_hIST_SUPPORTED
+PNG_EXPORT(142, void, png_set_hIST, (png_structp png_ptr,
+    png_infop info_ptr, png_const_uint_16p hist));
+#endif
+
+PNG_EXPORT(143, 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));
+
+PNG_EXPORT(144, 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));
+
+#ifdef PNG_oFFs_SUPPORTED
+PNG_EXPORT(145, png_uint_32, png_get_oFFs,
+    (png_const_structp png_ptr, png_const_infop info_ptr,
+    png_int_32 *offset_x, png_int_32 *offset_y, int *unit_type));
+#endif
+
+#ifdef PNG_oFFs_SUPPORTED
+PNG_EXPORT(146, 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));
+#endif
+
+#ifdef PNG_pCAL_SUPPORTED
+PNG_EXPORT(147, png_uint_32, png_get_pCAL,
+    (png_const_structp png_ptr, png_const_infop info_ptr,
+    png_charp *purpose, png_int_32 *X0, png_int_32 *X1, int *type,
+    int *nparams,
+    png_charp *units, png_charpp *params));
+#endif
+
+#ifdef PNG_pCAL_SUPPORTED
+PNG_EXPORT(148, void, png_set_pCAL, (png_structp png_ptr,
+    png_infop info_ptr,
+    png_const_charp purpose, png_int_32 X0, png_int_32 X1, int type,
+    int nparams, png_const_charp units, png_charpp params));
+#endif
+
+#ifdef PNG_pHYs_SUPPORTED
+PNG_EXPORT(149, png_uint_32, png_get_pHYs,
+    (png_const_structp png_ptr, png_const_infop info_ptr,
+    png_uint_32 *res_x, png_uint_32 *res_y, int *unit_type));
+#endif
+
+#ifdef PNG_pHYs_SUPPORTED
+PNG_EXPORT(150, 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));
+#endif
+
+PNG_EXPORT(151, png_uint_32, png_get_PLTE,
+    (png_const_structp png_ptr, png_const_infop info_ptr,
+    png_colorp *palette, int *num_palette));
+
+PNG_EXPORT(152, void, png_set_PLTE,
+    (png_structp png_ptr, png_infop info_ptr,
+    png_const_colorp palette, int num_palette));
+
+#ifdef PNG_sBIT_SUPPORTED
+PNG_EXPORT(153, png_uint_32, png_get_sBIT,
+    (png_const_structp png_ptr, png_infop info_ptr,
+    png_color_8p *sig_bit));
+#endif
+
+#ifdef PNG_sBIT_SUPPORTED
+PNG_EXPORT(154, void, png_set_sBIT,
+    (png_structp png_ptr, png_infop info_ptr, png_const_color_8p sig_bit));
+#endif
+
+#ifdef PNG_sRGB_SUPPORTED
+PNG_EXPORT(155, png_uint_32, png_get_sRGB, (png_const_structp png_ptr,
+    png_const_infop info_ptr, int *file_srgb_intent));
+#endif
+
+#ifdef PNG_sRGB_SUPPORTED
+PNG_EXPORT(156, void, png_set_sRGB,
+    (png_structp png_ptr, png_infop info_ptr, int srgb_intent));
+PNG_EXPORT(157, void, png_set_sRGB_gAMA_and_cHRM, (png_structp png_ptr,
+    png_infop info_ptr, int srgb_intent));
+#endif
+
+#ifdef PNG_iCCP_SUPPORTED
+PNG_EXPORT(158, png_uint_32, png_get_iCCP,
+    (png_const_structp png_ptr, png_const_infop info_ptr,
+    png_charpp name, int *compression_type, png_bytepp profile,
+    png_uint_32 *proflen));
+#endif
+
+#ifdef PNG_iCCP_SUPPORTED
+PNG_EXPORT(159, void, png_set_iCCP,
+    (png_structp png_ptr, png_infop info_ptr,
+    png_const_charp name, int compression_type, png_const_bytep profile,
+    png_uint_32 proflen));
+#endif
+
+#ifdef PNG_sPLT_SUPPORTED
+PNG_EXPORT(160, png_uint_32, png_get_sPLT,
+    (png_const_structp png_ptr, png_const_infop info_ptr,
+    png_sPLT_tpp entries));
+#endif
+
+#ifdef PNG_sPLT_SUPPORTED
+PNG_EXPORT(161, void, png_set_sPLT,
+    (png_structp png_ptr, png_infop info_ptr,
+    png_const_sPLT_tp entries, int nentries));
+#endif
+
+#ifdef PNG_TEXT_SUPPORTED
+/* png_get_text also returns the number of text chunks in *num_text */
+PNG_EXPORT(162, png_uint_32, png_get_text,
+    (png_const_structp png_ptr, png_const_infop info_ptr,
+    png_textp *text_ptr, int *num_text));
+#endif
+
+/* 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.
+ */
+
+#ifdef PNG_TEXT_SUPPORTED
+PNG_EXPORT(163, void, png_set_text,
+    (png_structp png_ptr, png_infop info_ptr,
+    png_const_textp text_ptr, int num_text));
+#endif
+
+#ifdef PNG_tIME_SUPPORTED
+PNG_EXPORT(164, png_uint_32, png_get_tIME,
+    (png_const_structp png_ptr, png_infop info_ptr, png_timep *mod_time));
+#endif
+
+#ifdef PNG_tIME_SUPPORTED
+PNG_EXPORT(165, void, png_set_tIME,
+    (png_structp png_ptr, png_infop info_ptr, png_const_timep mod_time));
+#endif
+
+#ifdef PNG_tRNS_SUPPORTED
+PNG_EXPORT(166, png_uint_32, png_get_tRNS,
+    (png_const_structp png_ptr, png_infop info_ptr,
+    png_bytep *trans_alpha, int *num_trans, png_color_16p *trans_color));
+#endif
+
+#ifdef PNG_tRNS_SUPPORTED
+PNG_EXPORT(167, void, png_set_tRNS,
+    (png_structp png_ptr, png_infop info_ptr,
+    png_const_bytep trans_alpha, int num_trans,
+    png_const_color_16p trans_color));
+#endif
+
+#ifdef PNG_sCAL_SUPPORTED
+PNG_FP_EXPORT(168, png_uint_32, png_get_sCAL,
+    (png_const_structp png_ptr, png_const_infop info_ptr,
+    int *unit, double *width, double *height))
+#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.
+ */
+PNG_FIXED_EXPORT(214, png_uint_32, png_get_sCAL_fixed,
+    (png_structp png_ptr, png_const_infop info_ptr, int *unit,
+    png_fixed_point *width,
+    png_fixed_point *height))
+#endif
+PNG_EXPORT(169, png_uint_32, png_get_sCAL_s,
+    (png_const_structp png_ptr, png_const_infop info_ptr,
+    int *unit, png_charpp swidth, png_charpp sheight));
+
+PNG_FP_EXPORT(170, void, png_set_sCAL,
+    (png_structp png_ptr, png_infop info_ptr,
+    int unit, double width, double height))
+PNG_FIXED_EXPORT(213, void, png_set_sCAL_fixed, (png_structp png_ptr,
+   png_infop info_ptr, int unit, png_fixed_point width,
+   png_fixed_point height))
+PNG_EXPORT(171, void, png_set_sCAL_s,
+    (png_structp png_ptr, png_infop info_ptr,
+    int unit, png_const_charp swidth, png_const_charp sheight));
+#endif /* PNG_sCAL_SUPPORTED */
+
+#ifdef PNG_HANDLE_AS_UNKNOWN_SUPPORTED
+/* Provide a list of chunks and how they are to be handled, if the built-in
+   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.  Because this turns off the default handling for chunks
+   that would otherwise be recognized the behavior of libpng transformations may
+   well become incorrect!
+      keep = 0: PNG_HANDLE_CHUNK_AS_DEFAULT: follow default behavior
+           = 1: PNG_HANDLE_CHUNK_NEVER:      do not keep
+           = 2: PNG_HANDLE_CHUNK_IF_SAFE:    keep only if safe-to-copy
+           = 3: PNG_HANDLE_CHUNK_ALWAYS:     keep even if unsafe-to-copy
+*/
+PNG_EXPORT(172, void, png_set_keep_unknown_chunks,
+    (png_structp png_ptr, int keep,
+    png_const_bytep chunk_list, int num_chunks));
+
+/* The handling code is returned; the result is therefore true (non-zero) if
+ * special handling is required, false for the default handling.
+ */
+PNG_EXPORT(173, int, png_handle_as_unknown, (png_structp png_ptr,
+    png_const_bytep chunk_name));
+#endif
+#ifdef PNG_UNKNOWN_CHUNKS_SUPPORTED
+PNG_EXPORT(174, void, png_set_unknown_chunks, (png_structp png_ptr,
+    png_infop info_ptr, png_const_unknown_chunkp unknowns,
+    int num_unknowns));
+PNG_EXPORT(175, void, png_set_unknown_chunk_location,
+    (png_structp png_ptr, png_infop info_ptr, int chunk, int location));
+PNG_EXPORT(176, int, png_get_unknown_chunks, (png_const_structp png_ptr,
+    png_const_infop info_ptr, png_unknown_chunkpp entries));
+#endif
+
+/* Png_free_data() will turn off the "valid" flag for anything it frees.
+ * 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);
+ */
+PNG_EXPORT(177, void, png_set_invalid,
+    (png_structp png_ptr, png_infop info_ptr, int mask));
+
+#ifdef PNG_INFO_IMAGE_SUPPORTED
+/* The "params" pointer is currently not used and is for future expansion. */
+PNG_EXPORT(178, void, png_read_png, (png_structp png_ptr, png_infop info_ptr,
+    int transforms, png_voidp params));
+PNG_EXPORT(179, void, png_write_png, (png_structp png_ptr, png_infop info_ptr,
+    int transforms, png_voidp params));
+#endif
+
+PNG_EXPORT(180, png_const_charp, png_get_copyright,
+    (png_const_structp png_ptr));
+PNG_EXPORT(181, png_const_charp, png_get_header_ver,
+    (png_const_structp png_ptr));
+PNG_EXPORT(182, png_const_charp, png_get_header_version,
+    (png_const_structp png_ptr));
+PNG_EXPORT(183, png_const_charp, png_get_libpng_ver,
+    (png_const_structp png_ptr));
+
+#ifdef PNG_MNG_FEATURES_SUPPORTED
+PNG_EXPORT(184, png_uint_32, png_permit_mng_features, (png_structp png_ptr,
+    png_uint_32 mng_features_permitted));
+#endif
+
+/* 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
+
+/* Strip the prepended error numbers ("#nnn ") from error and warning
+ * messages before passing them to the error or warning handler.
+ */
+#ifdef PNG_ERROR_NUMBERS_SUPPORTED
+PNG_EXPORT(185, void, png_set_strip_error_numbers,
+    (png_structp png_ptr,
+    png_uint_32 strip_mode));
+#endif
+
+/* Added in libpng-1.2.6 */
+#ifdef PNG_SET_USER_LIMITS_SUPPORTED
+PNG_EXPORT(186, void, png_set_user_limits, (png_structp png_ptr,
+    png_uint_32 user_width_max, png_uint_32 user_height_max));
+PNG_EXPORT(187, png_uint_32, png_get_user_width_max,
+    (png_const_structp png_ptr));
+PNG_EXPORT(188, png_uint_32, png_get_user_height_max,
+    (png_const_structp png_ptr));
+/* Added in libpng-1.4.0 */
+PNG_EXPORT(189, void, png_set_chunk_cache_max, (png_structp png_ptr,
+    png_uint_32 user_chunk_cache_max));
+PNG_EXPORT(190, png_uint_32, png_get_chunk_cache_max,
+    (png_const_structp png_ptr));
+/* Added in libpng-1.4.1 */
+PNG_EXPORT(191, void, png_set_chunk_malloc_max, (png_structp png_ptr,
+    png_alloc_size_t user_chunk_cache_max));
+PNG_EXPORT(192, png_alloc_size_t, png_get_chunk_malloc_max,
+    (png_const_structp png_ptr));
+#endif
+
+#if defined(PNG_INCH_CONVERSIONS_SUPPORTED)
+PNG_EXPORT(193, png_uint_32, png_get_pixels_per_inch,
+    (png_const_structp png_ptr, png_const_infop info_ptr));
+
+PNG_EXPORT(194, png_uint_32, png_get_x_pixels_per_inch,
+    (png_const_structp png_ptr, png_const_infop info_ptr));
+
+PNG_EXPORT(195, png_uint_32, png_get_y_pixels_per_inch,
+    (png_const_structp png_ptr, png_const_infop info_ptr));
+
+PNG_FP_EXPORT(196, float, png_get_x_offset_inches,
+    (png_const_structp png_ptr, png_const_infop info_ptr))
+#ifdef PNG_FIXED_POINT_SUPPORTED /* otherwise not implemented. */
+PNG_FIXED_EXPORT(211, png_fixed_point, png_get_x_offset_inches_fixed,
+    (png_structp png_ptr, png_const_infop info_ptr))
+#endif
+
+PNG_FP_EXPORT(197, float, png_get_y_offset_inches, (png_const_structp png_ptr,
+    png_const_infop info_ptr))
+#ifdef PNG_FIXED_POINT_SUPPORTED /* otherwise not implemented. */
+PNG_FIXED_EXPORT(212, png_fixed_point, png_get_y_offset_inches_fixed,
+    (png_structp png_ptr, png_const_infop info_ptr))
+#endif
+
+#  ifdef PNG_pHYs_SUPPORTED
+PNG_EXPORT(198, png_uint_32, png_get_pHYs_dpi, (png_const_structp png_ptr,
+    png_const_infop info_ptr, png_uint_32 *res_x, png_uint_32 *res_y,
+    int *unit_type));
+#  endif /* PNG_pHYs_SUPPORTED */
+#endif  /* PNG_INCH_CONVERSIONS_SUPPORTED */
+
+/* Added in libpng-1.4.0 */
+#ifdef PNG_IO_STATE_SUPPORTED
+PNG_EXPORT(199, png_uint_32, png_get_io_state, (png_structp png_ptr));
+
+PNG_EXPORTA(200, png_const_bytep, png_get_io_chunk_name,
+    (png_structp png_ptr), PNG_DEPRECATED);
+PNG_EXPORT(216, png_uint_32, png_get_io_chunk_type,
+    (png_const_structp png_ptr));
+
+/* The flags returned by png_get_io_state() are the following: */
+#  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 */
+#endif /* ?PNG_IO_STATE_SUPPORTED */
+
+/* Interlace support.  The following macros are always defined so that if
+ * libpng interlace handling is turned off the macros may be used to handle
+ * interlaced images within the application.
+ */
+#define PNG_INTERLACE_ADAM7_PASSES 7
+
+/* Two macros to return the first row and first column of the original,
+ * full, image which appears in a given pass.  'pass' is in the range 0
+ * to 6 and the result is in the range 0 to 7.
+ */
+#define PNG_PASS_START_ROW(pass) (((1&~(pass))<<(3-((pass)>>1)))&7)
+#define PNG_PASS_START_COL(pass) (((1& (pass))<<(3-(((pass)+1)>>1)))&7)
+
+/* A macro to return the offset between pixels in the output row for a pair of
+ * pixels in the input - effectively the inverse of the 'COL_SHIFT' macro that
+ * follows.  Note that ROW_OFFSET is the offset from one row to the next whereas
+ * COL_OFFSET is from one column to the next, within a row.
+ */
+#define PNG_PASS_ROW_OFFSET(pass) ((pass)>2?(8>>(((pass)-1)>>1)):8)
+#define PNG_PASS_COL_OFFSET(pass) (1<<((7-(pass))>>1))
+
+/* Two macros to help evaluate the number of rows or columns in each
+ * pass.  This is expressed as a shift - effectively log2 of the number or
+ * rows or columns in each 8x8 tile of the original image.
+ */
+#define PNG_PASS_ROW_SHIFT(pass) ((pass)>2?(8-(pass))>>1:3)
+#define PNG_PASS_COL_SHIFT(pass) ((pass)>1?(7-(pass))>>1:3)
+
+/* Hence two macros to determine the number of rows or columns in a given
+ * pass of an image given its height or width.  In fact these macros may
+ * return non-zero even though the sub-image is empty, because the other
+ * dimension may be empty for a small image.
+ */
+#define PNG_PASS_ROWS(height, pass) (((height)+(((1<<PNG_PASS_ROW_SHIFT(pass))\
+   -1)-PNG_PASS_START_ROW(pass)))>>PNG_PASS_ROW_SHIFT(pass))
+#define PNG_PASS_COLS(width, pass) (((width)+(((1<<PNG_PASS_COL_SHIFT(pass))\
+   -1)-PNG_PASS_START_COL(pass)))>>PNG_PASS_COL_SHIFT(pass))
+
+/* For the reader row callbacks (both progressive and sequential) it is
+ * necessary to find the row in the output image given a row in an interlaced
+ * image, so two more macros:
+ */
+#define PNG_ROW_FROM_PASS_ROW(yIn, pass) \
+   (((yIn)<<PNG_PASS_ROW_SHIFT(pass))+PNG_PASS_START_ROW(pass))
+#define PNG_COL_FROM_PASS_COL(xIn, pass) \
+   (((xIn)<<PNG_PASS_COL_SHIFT(pass))+PNG_PASS_START_COL(pass))
+
+/* Two macros which return a boolean (0 or 1) saying whether the given row
+ * or column is in a particular pass.  These use a common utility macro that
+ * returns a mask for a given pass - the offset 'off' selects the row or
+ * column version.  The mask has the appropriate bit set for each column in
+ * the tile.
+ */
+#define PNG_PASS_MASK(pass,off) ( \
+   ((0x110145AF>>(((7-(off))-(pass))<<2)) & 0xF) | \
+   ((0x01145AF0>>(((7-(off))-(pass))<<2)) & 0xF0))
+
+#define PNG_ROW_IN_INTERLACE_PASS(y, pass) \
+   ((PNG_PASS_MASK(pass,0) >> ((y)&7)) & 1)
+#define PNG_COL_IN_INTERLACE_PASS(x, pass) \
+   ((PNG_PASS_MASK(pass,1) >> ((x)&7)) & 1)
+
+#ifdef PNG_READ_COMPOSITE_NODIV_SUPPORTED
+/* 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
+ * 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. :-) ]
+ */
+
+ /* fg and bg should be in `gamma 1.0' space; alpha is the opacity */
+
+#  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)) + 128);                \
+       (composite) = (png_byte)((temp + (temp >> 8)) >> 8); }
+
+#  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)*(65535                      \
+           - (png_uint_32)(alpha)) + 32768);               \
+       (composite) = (png_uint_16)((temp + (temp >> 16)) >> 16); }
+
+#else  /* Standard method using integer division */
+
+#  define png_composite(composite, fg, alpha, bg)                          \
+     (composite) = (png_byte)(((png_uint_16)(fg) * (png_uint_16)(alpha) +  \
+     (png_uint_16)(bg) * (png_uint_16)(255 - (png_uint_16)(alpha)) +       \
+     127) / 255)
+
+#  define png_composite_16(composite, fg, alpha, bg)                         \
+     (composite) = (png_uint_16)(((png_uint_32)(fg) * (png_uint_32)(alpha) + \
+     (png_uint_32)(bg)*(png_uint_32)(65535 - (png_uint_32)(alpha)) +         \
+     32767) / 65535)
+#endif /* PNG_READ_COMPOSITE_NODIV_SUPPORTED */
+
+#ifdef PNG_READ_INT_FUNCTIONS_SUPPORTED
+PNG_EXPORT(201, png_uint_32, png_get_uint_32, (png_const_bytep buf));
+PNG_EXPORT(202, png_uint_16, png_get_uint_16, (png_const_bytep buf));
+PNG_EXPORT(203, png_int_32, png_get_int_32, (png_const_bytep buf));
+#endif
+
+PNG_EXPORT(204, png_uint_32, png_get_uint_31, (png_structp png_ptr,
+    png_const_bytep buf));
+/* No png_get_int_16 -- may be added if there's a real need for it. */
+
+/* Place a 32-bit number into a buffer in PNG byte order (big-endian). */
+#ifdef PNG_WRITE_INT_FUNCTIONS_SUPPORTED
+PNG_EXPORT(205, void, png_save_uint_32, (png_bytep buf, png_uint_32 i));
+#endif
+#ifdef PNG_SAVE_INT_32_SUPPORTED
+PNG_EXPORT(206, void, png_save_int_32, (png_bytep buf, png_int_32 i));
+#endif
+
+/* 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.
+ */
+#ifdef PNG_WRITE_INT_FUNCTIONS_SUPPORTED
+PNG_EXPORT(207, void, png_save_uint_16, (png_bytep buf, unsigned int i));
+/* No png_save_int_16 -- may be added if there's a real need for it. */
+#endif
+
+#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.
+ */
+#  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))))
+
+   /* From libpng-1.4.0 until 1.4.4, the png_get_uint_16 macro (but not the
+    * function) incorrectly returned a value of type png_uint_32.
+    */
+#  define png_get_uint_16(buf) \
+     ((png_uint_16) \
+      (((unsigned int)(*(buf)) << 8) + \
+       ((unsigned int)(*((buf) + 1)))))
+
+#  define png_get_int_32(buf) \
+     ((png_int_32)((*(buf) & 0x80) \
+      ? -((png_int_32)((png_get_uint_32(buf) ^ 0xffffffffL) + 1)) \
+      : (png_int_32)png_get_uint_32(buf)))
+#endif
+
+#if defined(PNG_READ_CHECK_FOR_INVALID_INDEX_SUPPORTED) || \
+    defined(PNG_WRITE_CHECK_FOR_INVALID_INDEX_SUPPORTED)
+PNG_EXPORT(234, void, png_set_check_for_invalid_index, (png_structp png_ptr,
+    int allowed));
+#endif
+
+/* Maintainer: Put new public prototypes here ^, in libpng.3, and project
+ * defs
+ */
+
+/* The last ordinal number (this is the *last* one already used; the next
+ * one to use is one more than this.)  Maintainer, remember to add an entry to
+ * scripts/symbols.def as well.
+ */
+#ifdef PNG_EXPORT_LAST_ORDINAL
+  PNG_EXPORT_LAST_ORDINAL(234);
+#endif
+
+#ifdef __cplusplus
+}
+#endif
+
+#endif /* PNG_VERSION_INFO_ONLY */
+/* Do not put anything past this line */
+#endif /* PNG_H */