[libpng16] Imported from libpng-1.6.3beta06.tar

with the right zlib headers.

ANNOUNCE

@@ -1,5 +1,5 @@
 
-Libpng 1.7.0alpha09 - January 21, 2013
+Libpng 1.6.3beta06 - May 12, 2013
 
 This is not intended to be a public release.  It will be replaced
 within a few weeks by a public version or by another test version.
@@ -9,118 +9,73 @@ Files available for download:
 Source files with LF line endings (for Unix/Linux) and with a
 "configure" script
 
-   1.7.0alpha09.tar.xz (LZMA-compressed, recommended)
-   1.7.0alpha09.tar.gz
+   1.6.3beta06.tar.xz (LZMA-compressed, recommended)
+   1.6.3beta06.tar.gz
 
 Source files with CRLF line endings (for Windows), without the
 "configure" script
 
-   lp170a09.7z  (LZMA-compressed, recommended)
-   lp170a09.zip
+   lp163b06.7z  (LZMA-compressed, recommended)
+   lp163b06.zip
 
 Other information:
 
-   1.7.0alpha09-README.txt
-   1.7.0alpha09-LICENSE.txt
+   1.6.3beta06-README.txt
+   1.6.3beta06-LICENSE.txt
 
-Changes since the last public release (1.6.0):
+Changes since the last public release (1.6.2):
 
-Version 1.7.0alpha01 [December 15, 2012]
-  Started 1.7.0 branch from libpng-1.6.0beta33.
-  Made 8-bit compose and rgb_to_grayscale accuracy improvements.  These
-    changes cause 16-bit arithmetic to be used for 8-bit data in the gamma
-    corrected compose and grayscale operations.  The arithmetic errors have
-    three sources all of which are fixed in this commit:
-    1) 8-bit linear calculations produce massive errors for lower intensity
-       values.
-    2) The old 16-bit "16 to 8" gamma table code erroneously wrote the lowest
-       output value into a table entry which corresponded to multiple output
-       values (so where the value written should have been the closest to the
-       transformed input value.)
-    3) In a number of cases the code to access the 16-bit table did not round;
-       it did a simple shift, which was wrong and made the side effects of (2)
-       even worse.
-  The new gamma code does not have the 16-to-8 problem at the cost of slightly
-    more calculations and the algorithm used to minimize the number of
-    calculations has been extended to all the 16-bit tables; it has advantages
-    for any significant gamma correction.
-  Rearranged png_struct, remove unused members, change png_set_filter handling
-    png_struct members rearranged - partly to reorder to avoid packing, partly
-    to put frequently accessed members at the start and partly to make
-    the grouping more clear. png_set_filter code has been rewritten and the
-    code shared with png_write_start_row moved to a common function.  Comments
-    in png.h have been made more clear. Minor fixes to
-    contrib/libtests/timepng.c and some of the png_*_tRNS logic, including
-    more error detection in png_set_tRNS.
-  Cleaned up USER_LIMITS feature, removing members from png_struct when not
-    required.
-  Rearranged ARM-NEON optimizations to isolate the machine specific code to
-    the hardware subdirectory, and add comments to pngrutil.c so that
-    implementors of other optimizations will know what to do.
-  Fixed cases of unquoted DESTDIR in Makefile.am.
-  Rebuilt Makefile.in, configure, etc., with autoconf-2.69 and automake-1.12.5.
+Version 1.6.3beta01 [April 25, 2013]
+  Revised stack marking in arm/filter_neon.S and configure.ac.
+  Ensure that NEON filter stuff is completely disabled when switched 'off'.
+    Previously the ARM NEON specific files were still built if the option
+    was switched 'off' as opposed to being explicitly disabled.
 
-Version 1.7.0alpha02 [December 17, 2012]
-  Removed functions that were deprecated in libpng-1.6.0:
-    png_reset_zstream(), png_info_init_3(), and png_data_freer() and its
-    associated flags.
-  Removed some duplicated lines from contrib/tools/scale.c and png.c.
-  Changed some instances of png_warning() to png_app_error().
-  Updated some left over "1.6.0beta32" in code sources.
-  Fixed a "png_structp" prototype (should be png_structrp) in arm_init.c
-  Updated the version-number hack in pngvalid.c
+Version 1.6.3beta02 [April 26, 2013]
+  Test for 'arm*' not just 'arm' in the host_cpu configure variable.
+  Rebuilt the configure scripts.
 
-Version 1.7.0alpha03 [December 19, 2012]
-  Cleaned up and enhanced the configure option; libpng now correctly
-    links and tests against zlib with a prefix; tests have been clarified; and
-    irrelevant or obsolete things (as defined by the autotools man page) have
-    been removed.
-  Documented new PNG_ABORT behavior in the manual and commentary in pngerror.c
-  Cleaned up whitespace in the synopsis portion of the manpage "libpng.3"
-  Fixed previous support for Z_PREFIX in configure builds, corrected sCAL APIs;
-    some of these use floating point arithmetic so they need to be disabled if
-    floating point arithmetic is switched off.  This is a quiet API change -
-    previously it appeared that the APIs were supported if fixed point
-    arithmetic was used internally, however they required certain APIs (floor,
-    modf, frexp, atof) that are part of C floating point support. Changed
-    png_fixed and the gamma code specific version of the same to avoid floor(),
-    which may be a library function (not an intrinsic). Removed unused #if 0
-    code.
-  Disassembled the version number in scripts/options.awk (necessary for
-    building on SunOs).
+Version 1.6.3beta03 [April 30, 2013]
+  Expanded manual paragraph about writing private chunks, particularly
+    the need to call png_set_keep_unknown_chunks() when writing them.
+  Avoid dereferencing NULL pointer possibly returned from
+     png_create_write_struct() (Andrew Church).
 
-Version 1.7.0alpha04 [December 23, 2012]
-  Added scripts/makefile.msys contributed by Christopher M. Wheeler
-  Made default Zlib compression settings be configurable. This adds #defines to
-    pnglibconf.h to control the defaults.
-  Fixed Windows build issues, enabled ARM compilation. Various warnings issued
-    by earlier versions of GCC fixed for Cygwin and Min/GW (which both use old
-    GCCs.) ARM support is enabled by default in zlib.props (unsupported by
-    Microsoft) and ARM compilation is made possible by deleting the check for
-    x86. The test programs cannot be run because they are not signed.
+Version 1.6.3beta05 [May 9, 2013]
+  Calculate our own zlib windowBits when decoding rather than trusting the
+    CMF bytes in the PNG datastream.
+  Added an option to force maximum window size for inflating, which was
+    the behavior of libpng15 and earlier.
+  Added png-fix-itxt and png-fix-too-far-back to the built programs and
+    removed warnings from the source code and timepng that are revealed as
+    a result.
+  Detect wrong libpng versions linked to png-fix-too-far-back, which currently
+    only works with libpng versions that can be made to reliably fail when
+    the deflate data contains an out-of-window reference.  This means only
+    1.6 and later.
+  Fixed gnu issues: g++ needs a static_cast, gcc 4.4.7 has a broken warning
+    message which it is easier to work round than ignore.
+  Updated contrib/pngminus/pnm2png.c (Paul Stewart):
+    Check for EOF
+    Ignore "#" delimited comments in input file to pnm2png.c.
+    Fixed whitespace handling
+    Added a call to png_set_packing()
+    Initialize dimension values so if sscanf fails at least we have known
+      invalid values.
+  Attempt to detect configuration issues with png-fix-too-far-back, which
+    requires both the correct libpng and the correct zlib to function
+    correctly.
+  Check ZLIB_VERNUM for mismatches, enclose #error in quotes
+  Added information in the documentation about problems with and fixes for
+    the bad CRC and bad iTXt chunk situations.
 
-Version 1.7.0alpha05 [December 24, 2012]
-  Discontinued distributing libpng-1.x.x.tar.bz2.
-  Discontinued distributing libpng-1.7.0-1.6.0-diff.txt and similar.
-
-Version 1.7.0alpha06 [January 1, 2013]
-  Fixed 'make distcheck' on SUN OS - libpng.so was not being removed
-
-Version 1.7.0alpha07 [January 10, 2013]
-  Fixed conceivable but difficult to repro overflow. Also added two test
-    programs to generate and test a PNG which should have the problem.
-
-Version 1.7.0alpha08 [January 17, 2013]
-  Corrected previous attempt at overflow detection in png_set_unknown_chunks().
-
-Version 1.7.0alpha09 [January 21, 2013]
-  Pulled changes to multi-chunk handling from libpng-1.6.0beta40.
-
-  ===========================================================================
-                       NOTICE November 17, 2012:
-     The location of the git repository at SourceForge has changed.
-               Visit http://libpng.sf.net/ for details.
-  ===========================================================================
+Version 1.6.3beta06 [May 12, 2013]
+  Allow contrib/pngminus/pnm2png.c to compile without WRITE_INVERT and
+    WRITE_PACK supported (writes error message that it can't read P1 or
+  Improved png-fix-too-far-back usage message, added --suffix option.
+  Revised contrib/pngminim/*/makefile to generate pnglibconf.h with the
+    right zlib header files.
+  Separated CPPFLAGS and CFLAGS in contrib/pngminim/*/makefile
 
 Send comments/corrections/commendations to png-mng-implement at lists.sf.net
 (subscription required; visit

CHANGES

@@ -3672,7 +3672,8 @@ Version 1.5.6 [November 3, 2011]
   No changes.
 
 Version 1.5.7beta01 [November 4, 2011]
-  Added support for ARM processor (Mans Rullgard)
+  Added support for ARM processor, when decoding all PNG up-filtered rows
+    and any other-filtered rows with 3 or 4 bytes per pixel (Mans Rullgard).
   Fixed bug in pngvalid on early allocation failure; fixed type cast in
     pngmem.c; pngvalid would attempt to call png_error() if the allocation
     of a png_struct or png_info failed. This would probably have led to a
@@ -3779,7 +3780,8 @@ Version 1.5.7 [December 15, 2011]
 
 Version 1.6.0beta01 [December 15, 2011]
   Removed machine-generated configure files from the GIT repository (they will
-    continue to appear in the tarball distributions).
+    continue to appear in the tarball distributions and in the libpng15 and
+    earlier GIT branches).
   Restored the new 'simplified' API, which was started in libpng-1.5.7beta02
     but later deleted from libpng-1.5.7beta05.
   Added example programs for the new 'simplified' API.
@@ -4304,79 +4306,24 @@ Version 1.6.0beta32 [November 25, 2012]
   Fixed error checking in the simplified write API (Olaf van der Spek)
   Made png_user_version_check() ok to use with libpng version 1.10.x and later.
 
-Version 1.6.0beta33 [December 10, 2012]
+Version 1.6.0beta33 [December 15, 2012]
   Fixed typo in png.c (PNG_SET_CHUNK_MALLOC_MAX should be PNG_CHUNK_MALLOC_MAX)
     that causes the MALLOC_MAX limit not to work (John Bowler)
   Change png_warning() to png_app_error() in pngwrite.c and comment the
     fall-through condition.
   Change png_warning() to png_app_warning() in png_write_tRNS().
+  Rearranged the ARM-NEON optimizations: Isolated the machine specific code
+    to the hardware subdirectory and added comments to pngrutil.c so that
+    implementors of other optimizations know what to do.
+  Fixed cases of unquoted DESTDIR in Makefile.am
+  Rebuilt Makefile.in, etc., with autoconf-2.69 and automake-1.12.5.
 
-Version 1.7.0alpha01 [December 15, 2012]
-  Started 1.7.0 branch from libpng-1.6.0beta33.
-  Made 8-bit compose and rgb_to_grayscale accuracy improvements.  These
-    changes cause 16-bit arithmetic to be used for 8-bit data in the gamma
-    corrected compose and grayscale operations.  The arithmetic errors have
-    three sources all of which are fixed in this commit:
-    1) 8-bit linear calculations produce massive errors for lower intensity
-       values.
-    2) The old 16-bit "16 to 8" gamma table code erroneously wrote the lowest
-       output value into a table entry which corresponded to multiple output
-       values (so where the value written should have been the closest to the
-       transformed input value.)
-    3) In a number of cases the code to access the 16-bit table did not round;
-       it did a simple shift, which was wrong and made the side effects of (2)
-       even worse.
-  The new gamma code does not have the 16-to-8 problem at the cost of slightly
-    more calculations and the algorithm used to minimize the number of
-    calculations has been extended to all the 16-bit tables; it has advantages
-    for any significant gamma correction.
-  Rearranged png_struct, remove unused members, change png_set_filter handling
-    png_struct members rearranged - partly to reorder to avoid packing, partly
-    to put frequently accessed members at the start and partly to make
-    the grouping more clear. png_set_filter code has been rewritten and the
-    code shared with png_write_start_row moved to a common function.  Comments
-    in png.h have been made more clear. Minor fixes to
-    contrib/libtests/timepng.c and some of the png_*_tRNS logic, including
-    more error detection in png_set_tRNS.
-  Cleaned up USER_LIMITS feature, removing members from png_struct when not
-    required.
-  Rearranged ARM-NEON optimizations to isolate the machine specific code to
-    the hardware subdirectory, and add comments to pngrutil.c so that
-    implementors of other optimizations will know what to do.
-  Fixed cases of unquoted DESTDIR in Makefile.am.
-  Rebuilt Makefile.in, configure, etc., with autoconf-2.69 and automake-1.12.5.
-
-Version 1.7.0alpha02 [December 17, 2012]
-  Removed functions that were deprecated in libpng-1.6.0:
-    png_reset_zstream(), png_info_init_3(), png_data_freer() and its
-    associated flags, png_malloc_default, and png_free_default.
-  Removed some duplicated lines from contrib/tools/scale.c and png.c.
-  Changed some instances of png_warning() to png_app_error().
-  Updated some left over "1.6.0beta32" in code sources.
-  Fixed a "png_structp" prototype (should be png_structrp) in arm_init.c
-  Updated the version-number hack in pngvalid.c
-  
-Version 1.7.0alpha03 [December 19, 2012]
-  Cleaned up and enhanced the configure option; libpng now correctly
-    links and tests against zlib with a prefix; tests have been clarified; and
-    irrelevant or obsolete things (as defined by the autotools man page) have
-    been removed.
-  Documented new PNG_ABORT behavior in the manual and commentary in pngerror.c
+Version 1.6.0beta34 [December 19, 2012]
   Cleaned up whitespace in the synopsis portion of the manpage "libpng.3"
-  Fixed previous support for Z_PREFIX in configure builds, corrected sCAL APIs;
-    some of these use floating point arithmetic so they need to be disabled if
-    floating point arithmetic is switched off.  This is a quiet API change -
-    previously it appeared that the APIs were supported if fixed point
-    arithmetic was used internally, however they required certain APIs (floor,
-    modf, frexp, atof) that are part of C floating point support. Changed
-    png_fixed and the gamma code specific version of the same to avoid floor(),
-    which may be a library function (not an intrinsic). Removed unused #if 0
-    code.
   Disassembled the version number in scripts/options.awk (necessary for
     building on SunOs).
 
-Version 1.7.0alpha04 [December 23, 2012]
-  Added scripts/makefile.msys contributed by Christopher M. Wheeler
+Version 1.6.0beta35 [December 23, 2012]
   Made default Zlib compression settings be configurable. This adds #defines to
     pnglibconf.h to control the defaults.
   Fixed Windows build issues, enabled ARM compilation. Various warnings issued
@@ -4385,28 +4332,234 @@ Version 1.7.0alpha04 [December 23, 2012]
     Microsoft) and ARM compilation is made possible by deleting the check for
     x86. The test programs cannot be run because they are not signed.
 
-Version 1.7.0alpha05 [December 24, 2012]
+Version 1.6.0beta36 [January 2, 2013]
   Discontinued distributing libpng-1.x.x.tar.bz2.
   Discontinued distributing libpng-1.7.0-1.6.0-diff.txt and similar.
-
-Version 1.7.0alpha06 [January 1, 2013]
+  Rebuilt configure with autoconf-2.69 (inadvertently not done in beta33)
   Fixed 'make distcheck' on SUN OS - libpng.so was not being removed
 
-Version 1.7.0alpha07 [January 10, 2013]
+Version 1.6.0beta37 [January 10, 2013]
   Fixed conceivable but difficult to repro overflow. Also added two test
     programs to generate and test a PNG which should have the problem.
 
-Version 1.7.0alpha08 [January 17, 2013]
-  Corrected previous attempt at overflow detection in png_set_unknown_chunks().
+Version 1.6.0beta39 [January 19, 2013]
+  Again corrected attempt at overflow detection in png_set_unknown_chunks().
+  Added overflow detection in png_set_sPLT() and png_set_text_2().
 
-Version 1.7.0alpha09 [January 21, 2013]
-  Pulled changes to multi-chunk handling from libpng-1.6.0beta40.
+Version 1.6.0beta40 [January 20, 2013]
+  Use consistent handling of overflows in text, sPLT and unknown png_set_* APIs
 
-  ===========================================================================
-                       NOTICE November 17, 2012:
-     The location of the git repository at SourceForge has changed.
-               Visit http://libpng.sf.net/ for details.
-  ===========================================================================
+Version 1.6.0rc01 [January 26, 2013]
+  No changes.
+
+Version 1.6.0rc02 [February 4, 2013]
+  Added png_get_palette_max() function.
+
+Version 1.6.0rc03 [February 5, 2013]
+  Fixed the png_get_palette_max API.
+
+Version 1.6.0rc04 [February 7, 2013]
+  Turn serial tests back on (recently turned off by autotools upgrade).
+
+Version 1.6.0rc05 [February 8, 2013]
+  Update manual about png_get_palette_max().
+
+Version 1.6.0rc06 [February 9, 2013]
+  Fixed missing dependency in --prefix builds The intermediate
+    internal 'prefix.h' file can only be generated correctly after
+    pnglibconf.h, however the dependency was not in Makefile.am.  The
+    symptoms are unpredictable depending on the order make chooses to
+    build pngprefix.h and pnglibconf.h, often the error goes unnoticed
+    because there is a system pnglibconf.h to use instead.
+
+Version 1.6.0rc07 [February 10, 2013]
+  Enclosed the new png_get_palette_max in #ifdef PNG_GET_PALETTE_MAX_SUPPORTED
+    block, and revised pnglibconf.h and pnglibconf.h.prebuilt accordingly.
+
+Version 1.6.0rc08 [February 10, 2013]
+  Fix typo in png.h #ifdef
+
+Version 1.6.0 [February 14, 2013]
+  No changes.
+
+Version 1.6.1beta01 [February 16, 2013]
+  Made symbol prefixing work with the ARM neon optimizations. Also allow
+    pngpriv.h to be included for preprocessor definitions only, so it can
+    be used in non-C/C++ files. Back ported from libpng 1.7.
+  Made sRGB check numbers consistent.
+  Ported libpng 1.5 options.awk/dfn file handling to 1.6, fixed one bug.
+  Removed cc -E workround, corrected png_get_palette_max API Tested on
+    SUN OS cc 5.9, which demonstrates the tokenization problem previously
+    avoided by using /lib/cpp.  Since all .dfn output is now protected in
+    double quotes unless it is to be macro substituted the fix should
+    work everywhere.
+  Enabled parallel tests - back ported from libpng-1.7.
+  scripts/pnglibconf.dfa formatting improvements back ported from libpng17.
+  Fixed a race condition in the creation of the build 'scripts' directory
+    while building with a parallel make.
+  Use approved/supported Android method to check for NEON, use Linux/POSIX
+    1003.1 API to check /proc/self/auxv avoiding buffer allocation and other
+    library calls (ported from libpng15).
+
+Version 1.6.1beta02 [February 19, 2013]
+  Use parentheses more consistently in "#if defined(MACRO)" tests.
+  Folded long lines.
+  Reenabled code to allow zero length PLTE chunks for MNG.
+
+Version 1.6.1beta03 [February 22, 2013]
+  Fixed ALIGNED_MEMORY support.
+  Allow run-time ARM NEON checking to be disabled. A new configure option:
+    --enable-arm-neon=always will stop the run-time checks. New checks
+    within arm/arm_init.c will cause the code not to be compiled unless
+    __ARM_NEON__ is set. This should make it fail safe (if someone asks
+    for it on then the build will fail if it can't be done.)
+  Updated the INSTALL document.
+
+Version 1.6.1beta04 [February 27, 2013]
+  Revised INSTALL to recommend using CPPFLAGS instead of INCLUDES.
+  Revised scripts/makefile.freebsd to respect ZLIBLIB and ZLIBINC.
+  Revised scripts/dfn.awk to work with the buggy MSYS awk that has trouble
+    with CRLF line endings.
+
+Version 1.6.1beta05 [March 1, 2013]
+  Avoid a possible memory leak in contrib/gregbook/readpng.c
+
+Version 1.6.1beta06 [March 4, 2013]
+  Better documentation of unknown handling API interactions.
+  Corrected Android builds and corrected libpng.vers with symbol
+    prefixing This adds an API to set optimization options externally,
+    providing an alternative and general solution for the non-portable
+    run-time tests used by the ARM Neon code.  It also makes those tests
+    compile and link on Android.
+  The order of settings vs options in pnglibconf.h is reversed to allow
+    settings to depend on options and options can now set (or override) the
+    defaults for settings.
+
+Version 1.6.1beta07 [March 7, 2013]
+  Corrected simplified API default gamma for color-mapped output, added
+    a flag to change default. In 1.6.0 when the simplified API was used
+    to produce color-mapped output from an input image with no gamma
+    information the gamma assumed for the input could be different from
+    that assumed for non-color-mapped output.  In particular 16-bit depth
+    input files were assumed to be sRGB encoded, whereas in the 'direct'
+    case they were assumed to have linear data.  This was an error.  The
+    fix makes the simplified API treat all input files the same way and
+    adds a new flag to the png_image::flags member to allow the
+    application/user to specify that 16-bit files contain sRGB data
+    rather than the default linear.
+  Fixed bugs in the pngpixel and makepng test programs.
+
+Version 1.6.1beta08 [March 7, 2013]
+  Fixed CMakelists.txt to allow building a single variant of the library
+    (Claudio Bley):
+  Introduced a PNG_LIB_TARGETS variable that lists all activated library
+    targets.  It is an error if this variable ends up empty, ie. you have
+    to build at least one library variant.
+  Made the *_COPY targets only depend on library targets actually being build.
+  Use PNG_LIB_TARGETS to unify a code path.
+  Changed the CREATE_SYMLINK macro to expect the full path to a file as the
+    first argument. When symlinking the filename component of that path is
+    determined and used as the link target.
+  Use copy_if_different in the CREATE_SYMLINK macro.
+
+Version 1.6.1beta09 [March 13, 2013]
+  Eliminated two warnings from the Intel C compiler. The warnings are
+    technically valid, although a reasonable treatment of division would
+    show it to be incorrect.
+
+Version 1.6.1rc01 [March 21, 2013]
+  No changes.
+
+Version 1.6.1 [March 28, 2013]
+  No changes.
+
+Version 1.6.2beta01 [April 14, 2013]
+  Updated documentation of 1.5.x to 1.6.x changes in iCCP chunk handling.
+  Fixed incorrect warning of excess deflate data. End condition - the
+    warning would be produced if the end of the deflate stream wasn't read
+    in the last row.  The warning is harmless.
+  Corrected the test on user transform changes on read. It was in the
+    png_set of the transform function, but that doesn't matter unless the
+    transform function changes the rowbuf size, and that is only valid if
+    transform_info is called.
+  Corrected a misplaced closing bracket in contrib/libtests/pngvalid.c
+    (Flavio Medeiros).
+  Corrected length written to uncompressed iTXt chunks (Samuli Suominen).
+    Bug was introduced in libpng-1.6.0.
+
+Version 1.6.2rc01 [April 18, 2013]
+  Added contrib/tools/fixitxt.c, to repair the erroneous iTXt chunk length
+    written by libpng-1.6.0 and 1.6.1.
+  Disallow storing sRGB information when the sRGB is not supported.
+
+Version 1.6.2rc02 [April 18, 2013]
+  Merge pngtest.c with libpng-1.7.0
+
+Version 1.6.2rc03 [April 22, 2013]
+  Trivial spelling cleanup.
+
+Version 1.6.2rc04 and 1.6.2rc05 [omitted]
+
+Version 1.6.2rc06 [April 24, 2013]
+  Reverted to version 1.6.2rc03.  Recent changes to arm/neon support
+    have been ported to libpng-1.7.0beta09 and will reappear in version
+    1.6.3beta01.
+
+Version 1.6.2 [April 25, 2013]
+  No changes.
+
+Version 1.6.3beta01 [April 25, 2013]
+  Revised stack marking in arm/filter_neon.S and configure.ac.
+  Ensure that NEON filter stuff is completely disabled when switched 'off'.
+    Previously the ARM NEON specific files were still built if the option
+    was switched 'off' as opposed to being explicitly disabled.
+
+Version 1.6.3beta02 [April 26, 2013]
+  Test for 'arm*' not just 'arm' in the host_cpu configure variable.
+  Rebuilt the configure scripts.
+
+Version 1.6.3beta03 [April 30, 2013]
+  Expanded manual paragraph about writing private chunks, particularly
+    the need to call png_set_keep_unknown_chunks() when writing them.
+  Avoid dereferencing NULL pointer possibly returned from
+     png_create_write_struct() (Andrew Church).
+
+Version 1.6.3beta05 [May 9, 2013]
+  Calculate our own zlib windowBits when decoding rather than trusting the
+    CMF bytes in the PNG datastream.
+  Added an option to force maximum window size for inflating, which was
+    the behavior of libpng15 and earlier.
+  Added png-fix-itxt and png-fix-too-far-back to the built programs and
+    removed warnings from the source code and timepng that are revealed as
+    a result.
+  Detect wrong libpng versions linked to png-fix-too-far-back, which currently
+    only works with libpng versions that can be made to reliably fail when
+    the deflate data contains an out-of-window reference.  This means only
+    1.6 and later.
+  Fixed gnu issues: g++ needs a static_cast, gcc 4.4.7 has a broken warning
+    message which it is easier to work round than ignore.
+  Updated contrib/pngminus/pnm2png.c (Paul Stewart):
+    Check for EOF
+    Ignore "#" delimited comments in input file to pnm2png.c.
+    Fixed whitespace handling
+    Added a call to png_set_packing()
+    Initialize dimension values so if sscanf fails at least we have known
+      invalid values.
+  Attempt to detect configuration issues with png-fix-too-far-back, which
+    requires both the correct libpng and the correct zlib to function
+    correctly.
+  Check ZLIB_VERNUM for mismatches, enclose #error in quotes
+  Added information in the documentation about problems with and fixes for
+    the bad CRC and bad iTXt chunk situations.
+
+Version 1.6.3beta06 [May 12, 2013]
+  Allow contrib/pngminus/pnm2png.c to compile without WRITE_INVERT and
+    WRITE_PACK supported (writes error message that it can't read P1 or
+    P4 PBM files).
+  Improved png-fix-too-far-back usage message, added --suffix option.
+  Revised contrib/pngminim/*/makefile to generate pnglibconf.h with the
+    right zlib header files.
+  Separated CPPFLAGS and CFLAGS in contrib/pngminim/*/makefile
 
 Send comments/corrections/commendations to png-mng-implement at lists.sf.net
 (subscription required; visit

CMakeLists.txt

@@ -34,8 +34,8 @@ project(libpng C)
 enable_testing()
 
 set(PNGLIB_MAJOR 1)
-set(PNGLIB_MINOR 7)
-set(PNGLIB_RELEASE 0)
+set(PNGLIB_MINOR 6)
+set(PNGLIB_RELEASE 3)
 set(PNGLIB_NAME libpng${PNGLIB_MAJOR}${PNGLIB_MINOR})
 set(PNGLIB_VERSION ${PNGLIB_MAJOR}.${PNGLIB_MINOR}.${PNGLIB_RELEASE})
 
@@ -139,8 +139,11 @@ endif()
 # NOW BUILD OUR TARGET
 include_directories(${CMAKE_CURRENT_SOURCE_DIR} ${ZLIB_INCLUDE_DIR})
 
+unset(PNG_LIB_TARGETS)
+
 if(PNG_SHARED)
   add_library(${PNG_LIB_NAME} SHARED ${libpng_sources})
+  set(PNG_LIB_TARGETS ${PNG_LIB_NAME})
   if(MSVC)
     # msvc does not append 'lib' - do it here to have consistent name
     set_target_properties(${PNG_LIB_NAME} PROPERTIES PREFIX "lib")
@@ -153,6 +156,7 @@ if(PNG_STATIC)
 # does not work without changing name
   set(PNG_LIB_NAME_STATIC ${PNG_LIB_NAME}_static)
   add_library(${PNG_LIB_NAME_STATIC} STATIC ${libpng_sources})
+  list(APPEND PNG_LIB_TARGETS ${PNG_LIB_NAME_STATIC})
   if(MSVC)
     # msvc does not append 'lib' - do it here to have consistent name
     set_target_properties(${PNG_LIB_NAME_STATIC} PROPERTIES PREFIX "lib")
@@ -160,6 +164,12 @@ if(PNG_STATIC)
   target_link_libraries(${PNG_LIB_NAME_STATIC} ${ZLIB_LIBRARY} ${M_LIBRARY})
 endif()
 
+if(NOT PNG_LIB_TARGETS)
+  message(SEND_ERROR
+    "No library variant selected to build. "
+    "Please enable at least one of the following options: PNG_STATIC, PNG_SHARED")
+endif()
+
 if(PNG_SHARED AND WIN32)
   set_target_properties(${PNG_LIB_NAME} PROPERTIES DEFINE_SYMBOL PNG_BUILD_DLL)
 endif()
@@ -222,14 +232,15 @@ macro(CREATE_SYMLINK SRC_FILE DEST_FILE)
   if(WIN32 AND NOT CYGWIN AND NOT MSYS)
     ADD_CUSTOM_COMMAND(
         OUTPUT ${CMAKE_LIBRARY_OUTPUT_DIRECTORY}/${DEST_FILE}   ${CMAKE_CURRENT_BINARY_DIR}/${DEST_FILE}
-        COMMAND ${CMAKE_COMMAND} -E copy        ${CMAKE_CURRENT_BINARY_DIR}/${SRC_FILE} ${CMAKE_LIBRARY_OUTPUT_DIRECTORY}/${DEST_FILE}
-        COMMAND ${CMAKE_COMMAND} -E copy        ${CMAKE_CURRENT_BINARY_DIR}/${SRC_FILE} ${CMAKE_CURRENT_BINARY_DIR}/${DEST_FILE}
-        DEPENDS ${PNG_LIB_NAME} ${PNG_LIB_NAME_STATIC}
+        COMMAND ${CMAKE_COMMAND} -E copy_if_different  "${SRC_FILE}" ${CMAKE_LIBRARY_OUTPUT_DIRECTORY}/${DEST_FILE}
+        COMMAND ${CMAKE_COMMAND} -E copy_if_different  "${SRC_FILE}" ${CMAKE_CURRENT_BINARY_DIR}/${DEST_FILE}
+        DEPENDS ${PNG_LIB_TARGETS}
         )
     ADD_CUSTOM_TARGET(${DEST_FILE}_COPY ALL DEPENDS ${CMAKE_LIBRARY_OUTPUT_DIRECTORY}/${DEST_FILE})
   else(WIN32 AND NOT CYGWIN AND NOT MSYS)
-    execute_process(COMMAND ${CMAKE_COMMAND} -E create_symlink ${SRC_FILE} ${CMAKE_LIBRARY_OUTPUT_DIRECTORY}/${DEST_FILE} WORKING_DIRECTORY ${CMAKE_CURRENT_BINARY_DIR})
-    execute_process(COMMAND ${CMAKE_COMMAND} -E create_symlink ${SRC_FILE} ${DEST_FILE} WORKING_DIRECTORY ${CMAKE_CURRENT_BINARY_DIR})
+    get_filename_component(LINK_TARGET "${SRC_FILE}" NAME)
+    execute_process(COMMAND ${CMAKE_COMMAND} -E create_symlink "${LINK_TARGET}" ${CMAKE_LIBRARY_OUTPUT_DIRECTORY}/${DEST_FILE} WORKING_DIRECTORY ${CMAKE_CURRENT_BINARY_DIR})
+    execute_process(COMMAND ${CMAKE_COMMAND} -E create_symlink "${LINK_TARGET}" ${DEST_FILE} WORKING_DIRECTORY ${CMAKE_CURRENT_BINARY_DIR})
   endif(WIN32 AND NOT CYGWIN AND NOT MSYS)
 endmacro()
 
@@ -260,9 +271,9 @@ endif(NOT WIN32 OR CYGWIN OR MINGW)
 # SET UP LINKS
 if(PNG_SHARED)
   set_target_properties(${PNG_LIB_NAME} PROPERTIES
-#   VERSION 17.${PNGLIB_RELEASE}.1.7.0alpha09
-    VERSION 17.${PNGLIB_RELEASE}.0
-    SOVERSION 17
+#   VERSION 16.${PNGLIB_RELEASE}.1.6.3beta06
+    VERSION 16.${PNGLIB_RELEASE}.0
+    SOVERSION 16
     CLEAN_DIRECT_OUTPUT 1)
 endif()
 if(PNG_STATIC)
@@ -287,40 +298,33 @@ endif()
 
 # INSTALL
 if(NOT SKIP_INSTALL_LIBRARIES AND NOT SKIP_INSTALL_ALL )
-  if(PNG_SHARED)
-    install(TARGETS ${PNG_LIB_NAME}
-        ${PNG_EXPORT_RULE}
-        RUNTIME DESTINATION bin
-        LIBRARY DESTINATION ${CMAKE_INSTALL_LIBDIR}
-        ARCHIVE DESTINATION ${CMAKE_INSTALL_LIBDIR})
+  install(TARGETS ${PNG_LIB_TARGETS}
+      ${PNG_EXPORT_RULE}
+      RUNTIME DESTINATION bin
+      LIBRARY DESTINATION ${CMAKE_INSTALL_LIBDIR}
+      ARCHIVE DESTINATION ${CMAKE_INSTALL_LIBDIR})
 
-    # Create a symlink for libpng.dll.a => libpng17.dll.a on Cygwin
+  if(PNG_SHARED)
+    # Create a symlink for libpng.dll.a => libpng16.dll.a on Cygwin
     if(CYGWIN OR MINGW)
        get_target_property(BUILD_TARGET_LOCATION ${PNG_LIB_NAME} LOCATION_${CMAKE_BUILD_TYPE})
-       get_filename_component(BUILD_TARGET_FILE ${BUILD_TARGET_LOCATION} NAME)
-       CREATE_SYMLINK(${BUILD_TARGET_FILE} libpng${CMAKE_IMPORT_LIBRARY_SUFFIX})
+       CREATE_SYMLINK(${BUILD_TARGET_LOCATION} libpng${CMAKE_IMPORT_LIBRARY_SUFFIX})
        install(FILES ${CMAKE_CURRENT_BINARY_DIR}/libpng${CMAKE_IMPORT_LIBRARY_SUFFIX}
          DESTINATION ${CMAKE_INSTALL_LIBDIR})
     endif(CYGWIN OR MINGW)
 
     if(NOT WIN32)
       get_target_property(BUILD_TARGET_LOCATION ${PNG_LIB_NAME} LOCATION_${CMAKE_BUILD_TYPE})
-      get_filename_component(BUILD_TARGET_FILE ${BUILD_TARGET_LOCATION} NAME)
-      CREATE_SYMLINK(${BUILD_TARGET_FILE} libpng${CMAKE_SHARED_LIBRARY_SUFFIX})
+      CREATE_SYMLINK(${BUILD_TARGET_LOCATION} libpng${CMAKE_SHARED_LIBRARY_SUFFIX})
       install(FILES ${CMAKE_CURRENT_BINARY_DIR}/libpng${CMAKE_SHARED_LIBRARY_SUFFIX}
          DESTINATION ${CMAKE_INSTALL_LIBDIR})
     endif(NOT WIN32)
   endif(PNG_SHARED)
 
   if(PNG_STATIC)
-    install(TARGETS ${PNG_LIB_NAME_STATIC}
-        ${PNG_EXPORT_RULE}
-        LIBRARY DESTINATION ${CMAKE_INSTALL_LIBDIR}
-        ARCHIVE DESTINATION ${CMAKE_INSTALL_LIBDIR})
     if(NOT WIN32 OR CYGWIN OR MINGW)
       get_target_property(BUILD_TARGET_LOCATION ${PNG_LIB_NAME_STATIC} LOCATION_${CMAKE_BUILD_TYPE})
-      get_filename_component(BUILD_TARGET_FILE ${BUILD_TARGET_LOCATION} NAME)
-      CREATE_SYMLINK(${BUILD_TARGET_FILE} libpng${CMAKE_STATIC_LIBRARY_SUFFIX})
+      CREATE_SYMLINK(${BUILD_TARGET_LOCATION} libpng${CMAKE_STATIC_LIBRARY_SUFFIX})
       install(FILES ${CMAKE_CURRENT_BINARY_DIR}/libpng${CMAKE_STATIC_LIBRARY_SUFFIX}
          DESTINATION ${CMAKE_INSTALL_LIBDIR})
     endif(NOT WIN32 OR CYGWIN OR MINGW)

INSTALL

@@ -41,19 +41,33 @@ is not already on your system.  zlib can usually be found
 wherever you got libpng.  zlib can be placed in another directory,
 at the same level as libpng.
 
+If your system already has a preinstalled zlib you will still need
+to have access to the zlib.h and zconf.h include files that
+correspond to the version of zlib that's installed.
+
+If you wish to test with a particular zlib that is not first in the
+standard library search path, put ZLIBLIB, ZLIBINC, CPPFLAGS, LDFLAGS,
+and LD_LIBRARY_PATH in your environment before running "make test"
+or "make distcheck":
+
+ZLIBLIB=/path/to/lib export ZLIBLIB
+ZLIBINC=/path/to/include export ZLIBINC
+CPPFLAGS="-I$ZLIBINC" export CPPFLAGS
+LDFLAGS="-L$ZLIBLIB" export LDFLAGS
+LD_LIBRARY_PATH="$ZLIBLIB:$LD_LIBRARY_PATH" export LD_LIBRARY_PATH
+
+If you are using one of the makefile scripts, put ZLIBLIB and ZLIBINC
+in your environment and type "make ZLIBLIB=$ZLIBLIB ZLIBINC=$ZLIBINC test".
+
 If you want to use "cmake" (see www.cmake.org), type
 
    cmake . -DCMAKE_INSTALL_PREFIX=/path
    make
    make install
 
-If your system already has a preinstalled zlib you will still need
-to have access to the zlib.h and zconf.h include files that
-correspond to the version of zlib that's installed.
-
 You can rename the directories that you downloaded (they
-might be called "libpng-x.y.z" or "libpngNN" and "zlib-1.2.5"
-or "zlib125") so that you have directories called "zlib" and "libpng".
+might be called "libpng-x.y.z" or "libpngNN" and "zlib-1.2.7"
+or "zlib127") so that you have directories called "zlib" and "libpng".
 
 Your directory structure should look like this:
 
@@ -71,6 +85,7 @@ Your directory structure should look like this:
              depcomp, install-sh, mkinstalldirs, test-pngtest.sh
           contrib
              gregbook
+             libtests
              pngminim
              pngminus
              pngsuite

LICENSE

@@ -10,8 +10,8 @@ this sentence.
 
 This code is released under the libpng license.
 
-libpng versions 1.2.6, August 15, 2004, through 1.7.0alpha09, January 21, 2013, are
-Copyright (c) 2004, 2006-2013 Glenn Randers-Pehrson, and are
+libpng versions 1.2.6, August 15, 2004, through 1.6.3beta06, May 12, 2013, 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
 
@@ -108,4 +108,4 @@ certification mark of the Open Source Initiative.
 
 Glenn Randers-Pehrson
 glennrp at users.sourceforge.net
-January 21, 2013
+May 12, 2013

Makefile.am

@@ -7,24 +7,52 @@ PNGLIB_BASENAME= libpng@PNGLIB_MAJOR@@PNGLIB_MINOR@
 ACLOCAL_AMFLAGS = -I scripts
 
 # test programs - run on make check, make distcheck
-TESTS_ENVIRONMENT= srcdir=$(srcdir)
-check_PROGRAMS= pngtest
+check_PROGRAMS= pngtest pngunknown pngstest pngvalid
+
+# Utilities - installed
+bin_PROGRAMS= png-fix-too-far-back png-fix-itxt
+
 pngtest_SOURCES = pngtest.c
 pngtest_LDADD = libpng@PNGLIB_MAJOR@@PNGLIB_MINOR@.la
-TESTS = test-pngtest.sh
 
-# Only do the following if the contrib directory is present.
-check_PROGRAMS+= pngvalid pngstest pngunknown
 pngvalid_SOURCES = contrib/libtests/pngvalid.c
-pngstest_SOURCES = contrib/libtests/pngstest.c
-pngunknown_SOURCES = contrib/libtests/pngunknown.c
 pngvalid_LDADD = libpng@PNGLIB_MAJOR@@PNGLIB_MINOR@.la
+
+pngstest_SOURCES = contrib/libtests/pngstest.c
 pngstest_LDADD = libpng@PNGLIB_MAJOR@@PNGLIB_MINOR@.la
+
+pngunknown_SOURCES = contrib/libtests/pngunknown.c
 pngunknown_LDADD = libpng@PNGLIB_MAJOR@@PNGLIB_MINOR@.la
-TESTS += contrib/libtests/test-pngunknown.sh\
-	 contrib/libtests/test-pngvalid-simple.sh\
-	 contrib/libtests/test-pngvalid-full.sh\
-	 contrib/libtests/test-pngstest.sh
+
+png_fix_too_far_back_SOURCES = contrib/tools/png-fix-too-far-back.c
+png_fix_too_far_back_LDADD = libpng@PNGLIB_MAJOR@@PNGLIB_MINOR@.la
+
+png_fix_itxt_SOURCES = contrib/tools/png-fix-itxt.c
+
+# Generally these are single line shell scripts to run a test with a particular
+# set of parameters:
+TESTS =\
+   tests/pngtest\
+   tests/pngvalid-gamma-16-to-8 tests/pngvalid-gamma-alpha-mode\
+   tests/pngvalid-gamma-background tests/pngvalid-gamma-expand16-alpha-mode\
+   tests/pngvalid-gamma-expand16-background\
+   tests/pngvalid-gamma-expand16-transform tests/pngvalid-gamma-sbit\
+   tests/pngvalid-gamma-threshold tests/pngvalid-gamma-transform\
+   tests/pngvalid-progressive-interlace-size\
+   tests/pngvalid-progressive-interlace-standard\
+   tests/pngvalid-progressive-interlace-transform\
+   tests/pngvalid-progressive-standard tests/pngvalid-standard\
+   tests/pngstest-0g01 tests/pngstest-0g02 tests/pngstest-0g04\
+   tests/pngstest-0g08 tests/pngstest-0g16 tests/pngstest-2c08\
+   tests/pngstest-2c16 tests/pngstest-3p01 tests/pngstest-3p02\
+   tests/pngstest-3p04 tests/pngstest-3p08 tests/pngstest-4a08\
+   tests/pngstest-4a16 tests/pngstest-6a08 tests/pngstest-6a16\
+   tests/pngstest-error tests/pngunknown-IDAT\
+   tests/pngunknown-discard tests/pngunknown-if-safe tests/pngunknown-sAPI\
+   tests/pngunknown-sTER tests/pngunknown-save tests/pngunknown-vpAg
+
+# These tests are expected, and required, to fail:
+XFAIL_TESTS = tests/pngstest-error
 
 # man pages
 dist_man_MANS= libpng.3 libpngpf.3 png.5
@@ -77,12 +105,14 @@ nodist_pkginclude_HEADERS= pnglibconf.h
 pkgconfigdir = @pkgconfigdir@
 pkgconfig_DATA = libpng@PNGLIB_MAJOR@@PNGLIB_MINOR@.pc
 
-#extra source distribution files.
+# Extra source distribution files, '${srcdir}' is used below to stop build files
+# from those directories being included.  This only works if the configure is
+# not done in the source directory!
 EXTRA_DIST= \
 	ANNOUNCE CHANGES INSTALL LICENSE README TODO \
 	pngtest.png pngbar.png pngnow.png pngbar.jpg autogen.sh \
 	${srcdir}/contrib ${srcdir}/projects ${srcdir}/scripts \
-	$(TESTS) \
+	$(TESTS) $(XFAIL_TESTS) tests/pngstest \
 	CMakeLists.txt example.c libpng-manual.txt
 
 SCRIPT_CLEANFILES=scripts/*.out scripts/*.chk scripts/pnglibconf.dfn
@@ -119,8 +149,7 @@ $(PNGLIB_BASENAME)-config: libpng-config
 scripts/sym.out scripts/vers.out: png.h pngconf.h pnglibconf.h
 scripts/prefix.out: png.h pngconf.h pnglibconf.out
 scripts/symbols.out: png.h pngconf.h $(srcdir)/scripts/pnglibconf.h.prebuilt
-
-pnglibconf.out: config.h
+scripts/intprefix.out: pnglibconf.h
 
 libpng.sym: scripts/sym.out
 	rm -f $@
@@ -133,7 +162,7 @@ if DO_PNG_PREFIX
 # Rename functions in scripts/prefix.out with a PNG_PREFIX prefix.
 # Rename macros in scripts/macro.lst from PNG_PREFIXpng_ to PNG_ (the actual
 # implementation of the macro).
-pnglibconf.h: pnglibconf.out scripts/prefix.out scripts/macro.lst config.h
+pnglibconf.h: pnglibconf.out scripts/prefix.out scripts/macro.lst
 	rm -f $@
 	$(AWK) 's==0 && NR>1{print prev}\
 	   s==0{prev=$$0}\
@@ -159,14 +188,15 @@ endif
 $(srcdir)/scripts/pnglibconf.h.prebuilt:
 	@echo "Attempting to build $@" >&2
 	@echo "This is a machine generated file, but if you want to make" >&2
-	@echo "a new one simply make 'scripts/pnglibconf.out' and copy that" >&2
+	@echo "a new one simply make 'scripts/pnglibconf.out', copy that" >&2
+	@echo "AND set PNG_ZLIB_VERNUM to 0 (you MUST do this)" >&2
 	@exit 1
 
 # The following is necessary to ensure that the local pnglibconf.h is used, not
 # an installed one (this can happen immediately after on a clean system if
 # 'make test' is the first thing the user does.)
-contrib/libtests/pngstest.o contrib/libtests/pngvalid.o pngtest.o: pnglibconf.h
-contrib/libtests/pngunknown.o: pnglibconf.h
+pngstest.o pngvalid.o pngtest.o pngunknown.o timepng.o: pnglibconf.h
+png-fix-too-far-back.o png-fix-itxt.o: pnglibconf.h
 
 # We must use -DPNG_NO_USE_READ_MACROS here even when the library may actually
 # be built with PNG_USE_READ_MACROS; this prevents the read macros from
@@ -181,16 +211,14 @@ SYMBOL_CFLAGS += -DPNG_PREFIX='@PNG_PREFIX@'
 endif
 
 .dfn.out:
-	rm -f $@ $*.c $*.tf[123]
-	test -d scripts || mkdir scripts
+	rm -f $@ $*.c $*.tf[12]
+	test -d scripts || mkdir scripts || test -d scripts
 	echo '#include "$<"' >$*.c
 	$(DFNCPP) $(DEFS) $(DEFAULT_INCLUDES) $(INCLUDES)\
 	    $(CPPFLAGS) $(SYMBOL_CFLAGS) $*.c > $*.tf1
-	$(SED) -n -e 's|^.*PNG_DEFN_MAGIC *-\(.*\)- *PNG_DEFN_END.*$$|\1|p'\
-	    $*.tf1 >$*.tf2
-	$(SED) -e 's| *PNG_JOIN *||g' -e 's| *$$||' $*.tf2 >$*.tf3
-	rm -f $*.c $*.tf[12]
-	mv $*.tf3 $@
+	$(AWK) -f "${srcdir}/scripts/dfn.awk" out="$*.tf2" $*.tf1 1>&2
+	rm -f $*.c $*.tf1
+	mv $*.tf2 $@
 
 # The .dfn file for pnglibconf.h is machine generated
 pnglibconf.dfn: scripts/pnglibconf.dfa scripts/options.awk pngconf.h pngusr.dfa $(DFA_XTRA)

README

@@ -1,4 +1,4 @@
-README for libpng version 1.7.0alpha09 - January 21, 2013 (shared library 17.0)
+README for libpng version 1.6.3beta06 - May 12, 2013 (shared library 16.0)
 See the note about version numbers near the top of png.h
 
 See INSTALL for instructions on how to install libpng.

arm/arm_init.c

@@ -1,54 +1,190 @@
 
 /* arm_init.c - NEON optimised filter functions
  *
- * Copyright (c) 2012 Glenn Randers-Pehrson
+ * Copyright (c) 2013 Glenn Randers-Pehrson
  * Written by Mans Rullgard, 2011.
- * Last changed in libpng 1.6.0 [(PENDING RELEASE)]
+ * Last changed in libpng 1.5.16 [(PENDING RELEASE)]
  *
  * This code is released under the libpng license.
  * For conditions of distribution and use, see the disclaimer
  * and license in png.h
  */
+/* Below, after checking __linux__, various non-C90 POSIX 1003.1 functions are
+ * called.
+ */
+#define _POSIX_SOURCE 1
+
 #include "../pngpriv.h"
 
-/* __arm__ is defined by GCC, MSVC defines _M_ARM to the ARM version number */
-#if defined __linux__ && defined __arm__
-#include <stdio.h>
+#ifdef PNG_ARM_NEON_SUPPORTED
+#ifdef PNG_ARM_NEON_CHECK_SUPPORTED /* Do run-time checks */
+#include <signal.h> /* for sig_atomic_t */
+
+#ifdef __ANDROID__
+/* Linux provides access to information about CPU capabilites via
+ * /proc/self/auxv, however Android blocks this while still claiming to be
+ * Linux.  The Andoid NDK, however, provides appropriate support.
+ *
+ * Documentation: http://www.kandroid.org/ndk/docs/CPU-ARM-NEON.html
+ */
+#include <cpu-features.h>
+
+static int
+png_have_neon(png_structp png_ptr)
+{
+   /* This is a whole lot easier than the mess below, however it is probably
+    * implemented as below, therefore it is better to cache the result (these
+    * function calls may be slow!)
+    */
+   PNG_UNUSED(png_ptr)
+   return android_getCpuFamily() == ANDROID_CPU_FAMILY_ARM &&
+      (android_getCpuFeatures() & ANDROID_CPU_ARM_FEATURE_NEON) != 0;
+}
+#elif defined(__linux__)
+/* The generic __linux__ implementation requires reading /proc/self/auxv and
+ * looking at each element for one that records NEON capabilities.
+ */
+#include <unistd.h> /* for POSIX 1003.1 */
+#include <errno.h>  /* for EINTR */
+
+#include <sys/types.h>
+#include <sys/stat.h>
+#include <fcntl.h>
 #include <elf.h>
 #include <asm/hwcap.h>
 
-static int png_have_hwcap(unsigned cap)
+/* A read call may be interrupted, in which case it returns -1 and sets errno to
+ * EINTR if nothing was done, otherwise (if something was done) a partial read
+ * may result.
+ */
+static size_t
+safe_read(png_structp png_ptr, int fd, void *buffer_in, size_t nbytes)
 {
-   FILE *f = fopen("/proc/self/auxv", "r");
-   Elf32_auxv_t aux;
-   int have_cap = 0;
+   size_t ntotal = 0;
+   char *buffer = png_voidcast(char*, buffer_in);
 
-   if (!f)
-      return 0;
-
-   while (fread(&aux, sizeof(aux), 1, f) > 0)
+   while (nbytes > 0)
    {
-      if (aux.a_type == AT_HWCAP &&
-          aux.a_un.a_val & cap)
+      unsigned int nread;
+      int iread;
+
+      /* Passing nread > INT_MAX to read is implementation defined in POSIX
+       * 1003.1, therefore despite the unsigned argument portable code must
+       * limit the value to INT_MAX!
+       */
+      if (nbytes > INT_MAX)
+         nread = INT_MAX;
+
+      else
+         nread = (unsigned int)/*SAFE*/nbytes;
+
+      iread = read(fd, buffer, nread);
+
+      if (iread == -1)
       {
-         have_cap = 1;
-         break;
+         /* This is the devil in the details, a read can terminate early with 0
+          * bytes read because of EINTR, yet it still returns -1 otherwise end
+          * of file cannot be distinguished.
+          */
+         if (errno != EINTR)
+         {
+            png_warning(png_ptr, "/proc read failed");
+            return 0; /* I.e. a permanent failure */
+         }
+      }
+
+      else if (iread < 0)
+      {
+         /* Not a valid 'read' result: */
+         png_warning(png_ptr, "OS /proc read bug");
+         return 0;
+      }
+
+      else if (iread > 0)
+      {
+         /* Continue reading until a permanent failure, or EOF */
+         buffer += iread;
+         nbytes -= (unsigned int)/*SAFE*/iread;
+         ntotal += (unsigned int)/*SAFE*/iread;
+      }
+
+      else
+         return ntotal;
+   }
+
+   return ntotal; /* nbytes == 0 */
+}
+
+static int
+png_have_neon(png_structp png_ptr)
+{
+   int fd = open("/proc/self/auxv", O_RDONLY);
+   Elf32_auxv_t aux;
+
+   /* Failsafe: failure to open means no NEON */
+   if (fd == -1)
+   {
+      png_warning(png_ptr, "/proc/self/auxv open failed");
+      return 0;
+   }
+
+   while (safe_read(png_ptr, fd, &aux, sizeof aux) == sizeof aux)
+   {
+      if (aux.a_type == AT_HWCAP && (aux.a_un.a_val & HWCAP_NEON) != 0)
+      {
+         close(fd);
+         return 1;
       }
    }
 
-   fclose(f);
-
-   return have_cap;
+   close(fd);
+   return 0;
 }
-#endif /* __linux__ && __arm__ */
+#else
+   /* We don't know how to do a run-time check on this system */
+#  error "no support for run-time ARM NEON checks"
+#endif /* OS checks */
+#endif /* PNG_ARM_NEON_CHECK_SUPPORTED */
+
+#ifndef PNG_ALIGNED_MEMORY_SUPPORTED
+#  error "ALIGNED_MEMORY is required; set: -DPNG_ALIGNED_MEMORY_SUPPORTED"
+#endif
 
 void
-png_init_filter_functions_neon(png_structrp pp, unsigned int bpp)
+png_init_filter_functions_neon(png_structp pp, unsigned int bpp)
 {
-#ifdef __arm__
-#ifdef __linux__
-   if (!png_have_hwcap(HWCAP_NEON))
-      return;
+#ifdef PNG_ARM_NEON_API_SUPPORTED
+   switch ((pp->options >> PNG_ARM_NEON) & 3)
+   {
+      case PNG_OPTION_UNSET:
+         /* Allow the run-time check to execute if it has been enabled -
+          * thus both API and CHECK can be turned on.  If it isn't supported
+          * this case will fall through to the 'default' below, which just
+          * returns.
+          */
+#endif /* PNG_ARM_NEON_API_SUPPORTED */
+#ifdef PNG_ARM_NEON_CHECK_SUPPORTED
+         {
+            static volatile sig_atomic_t no_neon = -1; /* not checked */
+
+            if (no_neon < 0)
+               no_neon = !png_have_neon(pp);
+
+            if (no_neon)
+               return;
+         }
+#ifdef PNG_ARM_NEON_API_SUPPORTED
+         break;
+#endif
+#endif /* PNG_ARM_NEON_CHECK_SUPPORTED */
+#ifdef PNG_ARM_NEON_API_SUPPORTED
+      case PNG_OPTION_ON:
+         /* Option turned on */
+         break;
+
+      default: /* OFF or INVALID */
+         return;
+   }
 #endif
 
    /* IMPORTANT: any new external functions used here must be declared using
@@ -79,8 +215,5 @@ png_init_filter_functions_neon(png_structrp pp, unsigned int bpp)
       pp->read_filter[PNG_FILTER_VALUE_PAETH-1] =
           png_read_filter_row_paeth4_neon;
    }
-#else
-   PNG_UNUSED(pp)
-   PNG_UNUSED(bpp)
-#endif
 }
+#endif /* PNG_ARM_NEON_SUPPORTED */

arm/filter_neon.S

@@ -1,20 +1,27 @@
 
 /* filter_neon.S - NEON optimised filter functions
  *
- * Copyright (c) 2011 Glenn Randers-Pehrson
+ * Copyright (c) 2013 Glenn Randers-Pehrson
  * Written by Mans Rullgard, 2011.
- * Last changed in libpng 1.5.7 [December 15, 2011]
+ * Last changed in libpng 1.5.16 [(PENDING RELEASE)]
  *
  * This code is released under the libpng license.
  * For conditions of distribution and use, see the disclaimer
  * and license in png.h
  */
 
-#ifdef __arm__
+/* This is required to get the symbol renames, which are #defines, and also
+ * includes the definition (or not) of PNG_ARM_NEON_SUPPORTED.
+ */
+#define PNG_VERSION_INFO_ONLY
+#include "../pngpriv.h"
+
 #if defined(__linux__) && defined(__ELF__)
 .section .note.GNU-stack,"",%progbits /* mark stack as non-executable */
 #endif
 
+#ifdef PNG_ARM_NEON_SUPPORTED
+
 #ifdef __ELF__
 #   define ELF
 #else
@@ -225,4 +232,4 @@ func    png_read_filter_row_paeth3_neon, export=1
 
         pop             {r4,pc}
 endfunc
-#endif
+#endif /* PNG_ARM_NEON_SUPPORTED */

autogen.sh

@@ -74,7 +74,7 @@ done
 #
 # The autotools generated files:
 libpng_autotools_files="Makefile.in aclocal.m4 config.guess config.h.in\
-   config.sub configure depcomp install-sh ltmain.sh missing"
+   config.sub configure depcomp install-sh ltmain.sh missing test-driver"
 #
 # These are separate because 'maintainer-clean' does not remove them.
 libpng_libtool_files="scripts/libtool.m4 scripts/ltoptions.m4\

configure.ac

@@ -18,7 +18,7 @@ AC_PREREQ([2.68])
 
 dnl Version number stuff here:
 
-AC_INIT([libpng],[1.7.0alpha09],[png-mng-implement@lists.sourceforge.net])
+AC_INIT([libpng],[1.6.3beta06],[png-mng-implement@lists.sourceforge.net])
 AC_CONFIG_MACRO_DIR([scripts])
 
 # libpng does not follow GNU file name conventions (hence 'foreign')
@@ -26,9 +26,11 @@ AC_CONFIG_MACRO_DIR([scripts])
 # silent-rules requires automake 1.11 or later
 # dist-xz requires automake 1.11 or later
 # 1.12.2 fixes a security issue in 1.11.2 and 1.12.1
-AM_INIT_AUTOMAKE([1.12.2 foreign dist-xz color-tests silent-rules])
-# was:
-# AM_INIT_AUTOMAKE
+# 1.13 is required for parallel tests
+AM_INIT_AUTOMAKE([1.13 foreign dist-xz color-tests silent-rules])
+# The following line causes --disable-maintainer-mode to be the default to
+# configure, this is necessary because libpng distributions cannot rely on the
+# time stamps of the autotools generated files being correct
 AM_MAINTAINER_MODE
 
 dnl configure.ac and Makefile.am expect automake 1.11.2 or a compatible later
@@ -37,10 +39,10 @@ dnl automake, so the following is not necessary (and is not defined anyway):
 dnl AM_PREREQ([1.11.2])
 dnl stop configure from automagically running automake
 
-PNGLIB_VERSION=1.7.0alpha09
+PNGLIB_VERSION=1.6.3beta06
 PNGLIB_MAJOR=1
-PNGLIB_MINOR=7
-PNGLIB_RELEASE=0
+PNGLIB_MINOR=6
+PNGLIB_RELEASE=3
 
 dnl End of version number stuff
 
@@ -53,8 +55,7 @@ AC_PROG_CC
 AM_PROG_AS
 LT_PATH_LD
 AC_PROG_CPP
-AC_CHECK_TOOL(SED, sed, :)
-AC_CHECK_TOOL(AWK, awk, :)
+AC_PROG_AWK
 AC_PROG_INSTALL
 AC_PROG_LN_S
 AC_PROG_MAKE_SET
@@ -64,30 +65,23 @@ dnl compatible later version may be used
 LT_INIT([win32-dll])
 LT_PREREQ([2.4.2])
 
-# On Solaris 10 and 12 CPP gets set to cc -E, however this still
-# does some input parsing.  We need strict ANSI-C style tokenization,
-# check this:
-AC_REQUIRE_CPP
-AC_MSG_CHECKING([for a C preprocessor that does not parse its input])
-AC_PREPROC_IFELSE([AC_LANG_SOURCE([[1.1.1 16BIT]])],
-   [DFNCPP="$CPP"],
-   [  DFNCPP=""
-      sav_CPP="$CPP"
-      for CPP in "${CC-cc} -E" "${CC-cc} -E -traditional-cpp" "/lib/cpp" "cpp"
-      do
-         AC_PREPROC_IFELSE([AC_LANG_SOURCE([[1.1.1 16BIT]])],
-            [DFNCPP="$CPP"]
-            [break],,)
-      done
-      CPP="$sav_CPP"
-   ])
-if test -n "$DFNCPP"; then
-   AC_MSG_RESULT([$DFNCPP])
-   AC_SUBST(DFNCPP)
+# Some awks crash when confronted with pnglibconf.dfa, do a test run now
+# to make sure this doesn't happen
+AC_MSG_CHECKING([that AWK works])
+if ${AWK} -f ${srcdir}/scripts/options.awk out="/dev/null" version=search\
+   ${srcdir}/pngconf.h ${srcdir}/scripts/pnglibconf.dfa\
+   ${srcdir}/pngusr.dfa 1>&2
+then
+   AC_MSG_RESULT([ok])
 else
-   AC_MSG_FAILURE([not found], 1)
+   AC_MSG_FAILURE([failed], 1)
 fi
 
+# This is a remnant of the old cc -E validation, where it may have been
+# necessary to use a different preprocessor for .dfn files
+DFNCPP="$CPP"
+AC_SUBST(DFNCPP)
+
 # -Werror cannot be passed to GCC in CFLAGS because configure will fail (it
 # checks the compiler with a program that generates a warning), add the
 # following option to deal with this
@@ -115,140 +109,30 @@ AC_ARG_ENABLE(werror,
 
 # Checks for header files.
 AC_HEADER_STDC
-# Headers used in pngpriv.h:
-AC_CHECK_HEADERS([stdlib.h string.h float.h fp.h math.h m68881.h])
-# Additional headers used in pngconf.h:
-AC_CHECK_HEADERS([limits.h stddef.h stdio.h setjmp.h time.h])
-# Used by pngread.c (for the simplified API):
-AC_CHECK_HEADERS([errno.h])
-# The following are not required for the standard 'make' build of libpng:
-# Additional requirements of contrib/libtests/makepng.c:
-AC_CHECK_HEADERS([ctype.h])
-# Additional requirements of contrib/libtests/pngvalid.c:
-AC_CHECK_HEADERS([fenv.h])
-# Additional requirements of contrib/libtests/tarith.c:
-AC_CHECK_HEADERS([assert.h])
 
 # Checks for typedefs, structures, and compiler characteristics.
-# Most of these have been removed from 1.7.0 because they checked for non-ANSI-C
-# behaviors and the result were, anyway, not used by earlier versions of libpng.
+AC_C_CONST
+AC_TYPE_SIZE_T
+AC_STRUCT_TM
 AC_C_RESTRICT
 
-# Checks for library functions; these need to be in order, least demanding to
-# most because the -l directives are added to the head of the list at each
-# check.
-# ANSI-C functions: all are required but they don't have to be implemented in
-# libc, it is perfectly ok to configure with an extra, wrapper, library preset
-# in LIBS.  NOTE: this list may not be complete
-AC_CHECK_FUNCS([memset memcpy strncpy],,
-               AC_MSG_FAILURE([missing ANSI-C functions]))
-
-# floor and ceil are required for FLOATING_POINT, but they can be turned off on
-# the configure command line (and they are independent.)  Default is to 'on'
-AC_ARG_ENABLE([floating-point],[Enable floating point APIs],,
-              [enable_floating_point=yes])
-AC_ARG_ENABLE([fixed-point],[Enable fixed point APIs],,
-              [enable_fixed_point=yes])
-AC_ARG_ENABLE([floating-arithmetic],[Use floating point arithmetic internally],,
-              [enable_floating_arithmetic=yes])
-
-# Check for a requirement for math library support
-if test "$enable_floating_arithmetic" = yes
-then
-   AC_SEARCH_LIBS([floor],[m],,
-                  [AC_MSG_WARN([not found])
-                   enable_floating_arithmetic=no])
-   AC_SEARCH_LIBS([frexp],[m],,
-                  [AC_MSG_WARN([not found])
-                   enable_floating_arithmetic=no])
-   AC_SEARCH_LIBS([modf],[m],,
-                  [AC_MSG_WARN([not found])
-                   enable_floating_arithmetic=no])
-   AC_SEARCH_LIBS([atof],[m],,
-                  [AC_MSG_WARN([not found])
-                   enable_floating_arithmetic=no])
-   AC_SEARCH_LIBS([pow],[m],,
-                  [AC_MSG_WARN([not found])
-                   enable_floating_arithmetic=no])
-fi
-
-# Set the relevant defines if required (only if required), this will override
-# anything on the command line.
-if test "$enable_floating_point" != yes
-then
-   AC_MSG_NOTICE([Floating point APIs disabled])
-   AC_DEFINE([PNG_NO_FLOATING_POINT],[1],
-             [No support for floating point APIs])
-fi
-if test "$enable_fixed_point" != yes
-then
-   AC_MSG_NOTICE([Fixed point APIs disabled])
-   AC_DEFINE([PNG_NO_FIXED_POINT],[1],
-             [No support for fixed point APIs])
-fi
-if test "$enable_floating_arithmetic" != yes
-then
-   AC_MSG_NOTICE([Fixed point arithmetic will be used])
-   AC_DEFINE([PNG_NO_FLOATING_ARITHMETIC],[1],
-             [No support for floating point arithmetic])
-fi
+# Checks for library functions.
+AC_FUNC_STRTOD
+AC_CHECK_FUNCS([memset], , AC_MSG_ERROR(memset not found in libc))
+AC_CHECK_FUNCS([pow], , AC_CHECK_LIB(m, pow, , AC_MSG_ERROR(cannot find pow)) )
+AC_ARG_WITH(zlib-prefix,
+   AS_HELP_STRING([[[--with-zlib-prefix]]],
+      [prefix that may have been used in installed zlib]),
+      [ZPREFIX=${withval}],
+      [ZPREFIX='z_'])
+AC_CHECK_LIB(z, zlibVersion, ,
+    AC_CHECK_LIB(z, ${ZPREFIX}zlibVersion, , AC_MSG_ERROR(zlib not installed)))
 
 # The following is for pngvalid, to ensure it catches FP errors even on
 # platforms that don't enable FP exceptions, the function appears in the math
 # library (typically), it's not an error if it is not found.
-AC_SEARCH_LIBS([feenableexcept],[m],AC_DEFINE([HAVE_FEENABLEEXCEPT],[1],
-      [Define to 1 if the feenableexcept function is available]))
-# Required by pngvalid:
-AC_SEARCH_LIBS([ceil],[m])
-
-# zlib checks and arguments;
-#  package zlib: argument is the name of the library
-#  zlib-header: the name of the header file
-#  zlib-prefix: the prefix for library functions, if any
-AC_ARG_WITH([zlib],
-   AS_HELP_STRING([[[--with-zlib=<name>]]],
-                  [base name of the zlib implementation (e.g. 'z')]),,
-   [with_zlib='z'])
-
-z_prefix=
-AC_ARG_WITH([zlib-prefix],
-   AS_HELP_STRING([[[--with-zlib-prefix=<prefix>]]],
-                  [prefix for zlib API functions]),
-   [if test "$withval" = "" -o "$withval" = yes; then
-      with_zlib_prefix='z_'
-      AC_DEFINE([PNG_ZLIB_PREFIX],[z_],[Standard zlib prefix])
-   elif test "${withval}" != "no"; then
-      AC_DEFINE_UNQUOTED([PNG_ZLIB_PREFIX],[${withval}],
-         [User defined zlib prefix])
-   else
-      with_zlib_prefix=
-   fi
-   if test "$with_zlib_prefix" != ""; then
-      AC_DEFINE([Z_PREFIX],[1],[Tell zlib.h to prefix function names])
-      z_prefix="#define Z_PREFIX 1"
-   fi])
-
-AC_ARG_WITH([zlib-header],
-   AS_HELP_STRING([[[--with-zlib-header='<file>' or '"file"']]],
-      [C include argument to locate zlib header file, e.g. <zlib.h>, take
-       care to put single quotes round this on the command line]),
-   [AC_DEFINE_UNQUOTED([PNG_ZLIB_HEADER],[${withval}],[Zlib header file])],
-   with_zlib_header='<zlib.h>')
-
-# AC_CHECK_LIB isn't quite enough for this because we need the special header
-# file too.
-LIBS="-l${with_zlib} $LIBS"
-AC_MSG_CHECKING(
-   [[Library '${with_zlib}' and #include ${with_zlib_header} for symbol '${with_zlib_prefix}zlibVersion']])
-AC_LINK_IFELSE(
-   [AC_LANG_PROGRAM(
-      [[
-${z_prefix}
-#include ${with_zlib_header}
-      ]],
-      [[(void)${with_zlib_prefix}zlibVersion();]])],
-   AC_MSG_RESULT([ok]),
-   AC_MSG_FAILURE([not found]))
+AC_CHECK_LIB([m], [feenableexcept])
+AC_CHECK_FUNCS([feenableexcept])
 
 AC_MSG_CHECKING([if using Solaris linker])
 SLD=`$LD --version 2>&1 | grep Solaris`
@@ -342,26 +226,56 @@ AC_ARG_WITH(libpng-prefix,
     fi])
 AM_CONDITIONAL([DO_PNG_PREFIX], [test "${with_libpng_prefix:-no}" != "no"])
 
-# Because GCC by default assembles code with an executable stack, even though it
-# compiles C code with a non-executable stack, it is necessary to do a fixup
-# here (this may by GCC specific)
-AC_SUBST([AM_CCASFLAGS], [-Wa,--noexecstack])
+# HOST SPECIFIC OPTIONS
+# =====================
+#
+# ARM
+# ===
+#
+# ARM NEON (SIMD) support.
 
 AC_ARG_ENABLE([arm-neon],
-   AS_HELP_STRING([[[--enable-arm-neon]]], [Enable ARM NEON optimizations]),
-   [if test "${enableval}" = "yes"; then
-      AC_DEFINE([PNG_FILTER_OPTIMIZATIONS],
-                [png_init_filter_functions_neon],
-                [ARM NEON filter initialization function])
-      AC_DEFINE([PNG_ALIGNED_MEMORY_SUPPORTED], [1],
-                [Align row buffers])
-    fi])
-AM_CONDITIONAL([PNG_ARM_NEON], [test "${enable_arm_neon:-no}" = yes])
+   AS_HELP_STRING([[[--enable-arm-neon]]],
+      [Enable ARM NEON optimizations: =no/off, check, api, yes/on:]
+      [no/off: disable the optimizations; check: use internal checking code]
+      [(deprecated and poorly supported); api: disable by default, enable by]
+      [a call to png_set_option; yes/on: turn on unconditionally.]),
+   [case "$enableval" in
+      no|off)
+         # disable the default enabling on __ARM_NEON__ systems:
+         AC_DEFINE([PNG_NO_ARM_NEON], [],
+                   [Disable ARM Neon optimizations])
+         # Prevent inclusion of the assembler files below:
+         enable_arm_neon=no;;
+      check)
+         AC_DEFINE([PNG_ARM_NEON_CHECK_SUPPORTED], [],
+                   [Check for ARM Neon support at run-time]);;
+      api)
+         AC_DEFINE([PNG_ARM_NEON_API_SUPPORTED], [],
+                   [Turn on ARM Neon optimizations at run-time]);;
+      yes|on)
+         AC_DEFINE([PNG_ARM_NEON_SUPPORTED], [],
+                   [Enable ARM Neon optimizations]);;
+      *)
+         AC_MSG_ERROR([--enable-arm-neon=${enable_arm_neon}: invalid value])
+   esac])
+
+# Add ARM specific files to all builds where the host_cpu is arm ('arm*') or
+# where ARM optimizations were explicitly requested (this allows a fallback if a
+# future host CPU does not match 'arm*')
+
+AM_CONDITIONAL([PNG_ARM_NEON],
+   [test "$enable_arm_neon" != 'no' &&
+    case "$host_cpu" in
+      arm*) :;;
+      *)    test "$enable_arm_neon" != '';;
+    esac])
 
 AC_MSG_NOTICE([[Extra options for compiler: $PNG_COPTS]])
 
 # Config files, substituting as above
-AC_CONFIG_FILES([Makefile libpng.pc])
-AC_CONFIG_FILES([libpng-config], [chmod +x libpng-config])
+AC_CONFIG_FILES([Makefile libpng.pc:libpng.pc.in])
+AC_CONFIG_FILES([libpng-config:libpng-config.in],
+   [chmod +x libpng-config])
 
 AC_OUTPUT

contrib/examples/pngpixel.c

@@ -37,7 +37,7 @@ component(png_const_bytep row, png_uint_32 x, unsigned int c,
     * bytes wide.  Since the row fitted into memory, however, the following must
     * work:
     */
-   png_uint_32 bit_offset_hi = bit_depth * ((x >> 6) * channels + c);
+   png_uint_32 bit_offset_hi = bit_depth * ((x >> 6) * channels);
    png_uint_32 bit_offset_lo = bit_depth * ((x & 0x3f) * channels + c);
 
    row = (png_const_bytep)(((PNG_CONST png_byte (*)[8])row) + bit_offset_hi);

contrib/gregbook/Makefile.sgi

@@ -23,9 +23,9 @@
 
 # macros --------------------------------------------------------------------
 
-PNGINC = -I/usr/local/include/libpng17
-PNGLIB = -L/usr/local/lib -lpng17	  # dynamically linked against libpng
-#PNGLIB = /usr/local/lib/libpng17.a # statically linked against libpng
+PNGINC = -I/usr/local/include/libpng16
+PNGLIB = -L/usr/local/lib -lpng16	  # dynamically linked against libpng
+#PNGLIB = /usr/local/lib/libpng16.a # statically linked against libpng
 # or:
 #PNGINC = -I../..
 #PNGLIB = -L../.. -lpng

contrib/gregbook/Makefile.unx

@@ -26,14 +26,14 @@
 # macros --------------------------------------------------------------------
 
 #PNGDIR = /usr/local/lib
-#PNGINC = -I/usr/local/include/libpng17
-#PNGLIBd = -L$(PNGDIR) -lpng17 # dynamically linked, installed libpng
-#PNGLIBs = $(PNGDIR)/libpng17.a # statically linked, installed libpng
+#PNGINC = -I/usr/local/include/libpng16
+#PNGLIBd = -L$(PNGDIR) -lpng16 # dynamically linked, installed libpng
+#PNGLIBs = $(PNGDIR)/libpng16.a # statically linked, installed libpng
 # or:
 PNGDIR = ../..#	this one is for libpng-x.y.z/contrib/gregbook builds
 #PNGDIR = ../libpng
 PNGINC = -I$(PNGDIR)
-PNGLIBd = -Wl,-rpath,$(PNGDIR) -L$(PNGDIR) -lpng17	# dynamically linked
+PNGLIBd = -Wl,-rpath,$(PNGDIR) -L$(PNGDIR) -lpng16	# dynamically linked
 PNGLIBs = $(PNGDIR)/libpng.a		# statically linked, local libpng
 
 ZDIR = /usr/local/lib

contrib/gregbook/readpng.c

@@ -215,6 +215,10 @@ uch *readpng_get_image(double display_exponent, int *pChannels, ulg *pRowbytes)
      * libpng function */
 
     if (setjmp(png_jmpbuf(png_ptr))) {
+        free(image_data);
+        image_data = NULL;
+        free(row_pointers);
+        row_pointers = NULL;
         png_destroy_read_struct(&png_ptr, &info_ptr, NULL);
         return NULL;
     }

contrib/libtests/gentests.sh

@@ -1,8 +1,8 @@
 #!/bin/sh
 #
-# Copyright (c) 2012 John Cunningham Bowler
+# Copyright (c) 2013 John Cunningham Bowler
 #
-# Last changed in libpng 1.6.0 [(PENDING RELEASE)]
+# Last changed in libpng 1.6.0 [February 14, 2013]
 #
 # This code is released under the libpng license.
 # For conditions of distribution and use, see the disclaimer

contrib/libtests/makepng.c

@@ -1,8 +1,8 @@
 /* makepng.c
  *
- * Copyright (c) 2012 John Cunningham Bowler
+ * Copyright (c) 2013 John Cunningham Bowler
  *
- * Last changed in libpng 1.6.0 [(PENDING RELEASE)]
+ * Last changed in libpng 1.6.1 [March 28, 2013]
  *
  * This code is released under the libpng license.
  * For conditions of distribution and use, see the disclaimer
@@ -83,7 +83,7 @@
 #include <math.h>
 #include <errno.h>
 
-#if (defined HAVE_CONFIG_H) && !(defined PNG_NO_CONFIG_H)
+#if defined(HAVE_CONFIG_H) && !defined(PNG_NO_CONFIG_H)
 #  include <config.h>
 #endif
 
@@ -440,7 +440,7 @@ generate_row(png_bytep row, size_t rowbytes, unsigned int y, int color_type,
       /* Palette with fixed color: the image rows are all 0 and the image width
        * is 16.
        */
-      memset(row, rowbytes, 0);
+      memset(row, 0, rowbytes);
    }
 
    else if (colors[0] == channels_of_type(color_type))
@@ -624,8 +624,8 @@ write_png(const char **name, FILE *fp, int color_type, int bit_depth,
 
             gamma_table[0] = 0;
 
-            for (i=0; i<255; ++i)
-               gamma_table[i] = (png_byte)floor(pow(i/255.,conv) * 255 + 127.5);
+            for (i=1; i<255; ++i)
+               gamma_table[i] = (png_byte)floor(pow(i/255.,conv) * 255 + .5);
 
             gamma_table[255] = 255;
          }

contrib/libtests/pngstest.c

@@ -1,9 +1,9 @@
 /*-
  * pngstest.c
  *
- * Copyright (c) 2012 John Cunningham Bowler
+ * Copyright (c) 2013 John Cunningham Bowler
  *
- * Last changed in libpng 1.6.0 [(PENDING RELEASE)]
+ * Last changed in libpng 1.6.1 [March 28, 2013]
  *
  * This code is released under the libpng license.
  * For conditions of distribution and use, see the disclaimer
@@ -22,7 +22,7 @@
 #include <ctype.h>
 #include <math.h>
 
-#if (defined HAVE_CONFIG_H) && !(defined PNG_NO_CONFIG_H)
+#if defined(HAVE_CONFIG_H) && !defined(PNG_NO_CONFIG_H)
 #  include <config.h>
 #endif
 
@@ -62,6 +62,12 @@
 #  define aligncastconst(type, value) ((const void*)(value))
 #endif /* __cplusplus */
 
+/* During parallel runs of pngstest each temporary file needs a unique name,
+ * this is used to permit uniqueness using a command line argument which can be
+ * up to 22 characters long.
+ */
+static char tmpf[23] = "TMP";
+
 /* Generate random bytes.  This uses a boring repeatable algorithm and it
  * is implemented here so that it gives the same set of numbers on every
  * architecture.  It's a linear congruential generator (Knuth or Sedgewick
@@ -309,6 +315,7 @@ compare_16bit(int v1, int v2, int error_limit, int multiple_algorithms)
 #define KEEP_GOING 32
 #define ACCUMULATE 64
 #define FAST_WRITE 128
+#define sRGB_16BIT 256
 
 static void
 print_opts(png_uint_32 opts)
@@ -329,6 +336,8 @@ print_opts(png_uint_32 opts)
       printf(" --accumulate");
    if (!(opts & FAST_WRITE)) /* --fast is currently the default */
       printf(" --slow");
+   if (opts & sRGB_16BIT)
+      printf(" --sRGB-16bit");
 }
 
 #define FORMAT_NO_CHANGE 0x80000000 /* additional flag */
@@ -3020,6 +3029,10 @@ read_file(Image *image, png_uint_32 format, png_const_colorp background)
          return logerror(image, "file init: ", image->file_name, "");
    }
 
+   /* This must be set after the begin_read call: */
+   if (image->opts & sRGB_16BIT)
+      image->image.flags |= PNG_IMAGE_FLAG_16BIT_sRGB;
+
    /* Have an initialized image with all the data we need plus, maybe, an
     * allocated file (myfile) or buffer (mybuffer) that need to be freed.
     */
@@ -3198,7 +3211,7 @@ write_one_file(Image *output, Image *image, int convert_to_8bit)
       static int counter = 0;
       char name[32];
 
-      sprintf(name, "TMP%d.png", ++counter);
+      sprintf(name, "%s%d.png", tmpf, ++counter);
 
       if (png_image_write_to_file(&image->image, name, convert_to_8bit,
          image->buffer+16, (png_int_32)image->stride, image->colormap))
@@ -3482,6 +3495,34 @@ main(int argc, char **argv)
          opts &= ~KEEP_GOING;
       else if (strcmp(arg, "--strict") == 0)
          opts |= STRICT;
+      else if (strcmp(arg, "--sRGB-16bit") == 0)
+         opts |= sRGB_16BIT;
+      else if (strcmp(arg, "--linear-16bit") == 0)
+         opts &= ~sRGB_16BIT;
+      else if (strcmp(arg, "--tmpfile") == 0)
+      {
+         if (c+1 < argc)
+         {
+            if (strlen(argv[++c]) >= sizeof tmpf)
+            {
+               fflush(stdout);
+               fprintf(stderr, "%s: %s is too long for a temp file prefix\n",
+                  argv[0], argv[c]);
+               exit(99);
+            }
+
+            /* Safe: checked above */
+            strcpy(tmpf, argv[c]);
+         }
+
+         else
+         {
+            fflush(stdout);
+            fprintf(stderr, "%s: %s requires a temporary file prefix\n",
+               argv[0], arg);
+            exit(99);
+         }
+      }
       else if (strcmp(arg, "--touch") == 0)
       {
          if (c+1 < argc)
@@ -3492,7 +3533,7 @@ main(int argc, char **argv)
             fflush(stdout);
             fprintf(stderr, "%s: %s requires a file name argument\n",
                argv[0], arg);
-            exit(1);
+            exit(99);
          }
       }
       else if (arg[0] == '+')
@@ -3500,7 +3541,7 @@ main(int argc, char **argv)
          png_uint_32 format = formatof(arg+1);
 
          if (format > FORMAT_COUNT)
-            exit(1);
+            exit(99);
 
          format_set(&formats, format);
       }
@@ -3508,7 +3549,7 @@ main(int argc, char **argv)
       {
          fflush(stdout);
          fprintf(stderr, "%s: unknown option: %s\n", argv[0], arg);
-         exit(1);
+         exit(99);
       }
       else
       {
@@ -3557,7 +3598,7 @@ main(int argc, char **argv)
                buffer[4095] = 0;
                fprintf(stderr, "%s...%s: file name too long\n", buffer,
                   buffer+(4096-32));
-               exit(1);
+               exit(99);
             }
          }
 
@@ -3676,7 +3717,7 @@ main(int argc, char **argv)
          {
             fflush(stdout);
             fprintf(stderr, "%s: write failed\n", touch);
-            exit(1);
+            exit(99);
          }
       }
 
@@ -3684,7 +3725,7 @@ main(int argc, char **argv)
       {
          fflush(stdout);
          fprintf(stderr, "%s: open failed\n", touch);
-         exit(1);
+         exit(99);
       }
    }
 
@@ -3695,6 +3736,7 @@ main(int argc, char **argv)
 int main(void)
 {
    fprintf(stderr, "pngstest: no read support in libpng, test skipped\n");
-   return 0;
+   /* So the test is skipped: */
+   return 77;
 }
 #endif /* PNG_SIMPLIFIED_READ_SUPPORTED */

contrib/libtests/pngunknown.c

@@ -1,8 +1,8 @@
 
 /* pngunknown.c - test the read side unknown chunk handling
  *
- * Last changed in libpng 1.6.0 [(PENDING RELEASE)]
- * Copyright (c) 2012 Glenn Randers-Pehrson
+ * Last changed in libpng 1.6.0 [February 14, 2013]
+ * Copyright (c) 2013 Glenn Randers-Pehrson
  * Written by John Cunningham Bowler
  *
  * This code is released under the libpng license.
@@ -139,23 +139,128 @@ static struct
    { "PLTE", PNG_INFO_PLTE, png_PLTE, 0, 0, ABSENT, 0 },
 
    /* Non-critical chunks that libpng handles */
-   { "bKGD", PNG_INFO_bKGD, png_bKGD, 0, 1,  START, 0 },
-   { "cHRM", PNG_INFO_cHRM, png_cHRM, 0, 1,  START, 0 },
-   { "gAMA", PNG_INFO_gAMA, png_gAMA, 0, 1,  START, 0 },
-   { "hIST", PNG_INFO_hIST, png_hIST, 0, 1, ABSENT, 0 },
-   { "iCCP", PNG_INFO_iCCP, png_iCCP, 0, 1, ABSENT, 0 },
-   { "iTXt", PNG_INFO_iTXt, png_iTXt, 0, 1, ABSENT, 0 },
-   { "oFFs", PNG_INFO_oFFs, png_oFFs, 0, 1,  START, 0 },
-   { "pCAL", PNG_INFO_pCAL, png_pCAL, 0, 1,  START, 0 },
-   { "pHYs", PNG_INFO_pHYs, png_pHYs, 0, 1,  START, 0 },
-   { "sBIT", PNG_INFO_sBIT, png_sBIT, 0, 1,  START, 0 },
-   { "sCAL", PNG_INFO_sCAL, png_sCAL, 0, 1,  START, 0 },
-   { "sPLT", PNG_INFO_sPLT, png_sPLT, 0, 1, ABSENT, 0 },
-   { "sRGB", PNG_INFO_sRGB, png_sRGB, 0, 1,  START, 0 },
-   { "tEXt", PNG_INFO_tEXt, png_tEXt, 0, 1,  START, 0 },
-   { "tIME", PNG_INFO_tIME, png_tIME, 0, 1,  START, 0 },
-   { "tRNS", PNG_INFO_tRNS, png_tRNS, 0, 0, ABSENT, 0 },
-   { "zTXt", PNG_INFO_zTXt, png_zTXt, 0, 1,    END, 0 },
+   /* This is a mess but it seems to be the only way to do it - there is no way to
+    * check for definition outside a #if.
+    */
+   { "bKGD", PNG_INFO_bKGD, png_bKGD,
+#     ifdef PNG_READ_bKGD_SUPPORTED
+         0,
+#     else
+         1,
+#     endif
+      1,  START, 0 },
+   { "cHRM", PNG_INFO_cHRM, png_cHRM,
+#     ifdef PNG_READ_cHRM_SUPPORTED
+         0,
+#     else
+         1,
+#     endif
+      1,  START, 0 },
+   { "gAMA", PNG_INFO_gAMA, png_gAMA,
+#     ifdef PNG_READ_gAMA_SUPPORTED
+         0,
+#     else
+         1,
+#     endif
+      1,  START, 0 },
+   { "hIST", PNG_INFO_hIST, png_hIST,
+#     ifdef PNG_READ_hIST_SUPPORTED
+         0,
+#     else
+         1,
+#     endif
+      1, ABSENT, 0 },
+   { "iCCP", PNG_INFO_iCCP, png_iCCP,
+#     ifdef PNG_READ_iCCP_SUPPORTED
+         0,
+#     else
+         1,
+#     endif
+      1, ABSENT, 0 },
+   { "iTXt", PNG_INFO_iTXt, png_iTXt,
+#     ifdef PNG_READ_iTXt_SUPPORTED
+         0,
+#     else
+         1,
+#     endif
+      1, ABSENT, 0 },
+   { "oFFs", PNG_INFO_oFFs, png_oFFs,
+#     ifdef PNG_READ_oFFs_SUPPORTED
+         0,
+#     else
+         1,
+#     endif
+      1,  START, 0 },
+   { "pCAL", PNG_INFO_pCAL, png_pCAL,
+#     ifdef PNG_READ_pCAL_SUPPORTED
+         0,
+#     else
+         1,
+#     endif
+      1,  START, 0 },
+   { "pHYs", PNG_INFO_pHYs, png_pHYs,
+#     ifdef PNG_READ_pHYs_SUPPORTED
+         0,
+#     else
+         1,
+#     endif
+      1,  START, 0 },
+   { "sBIT", PNG_INFO_sBIT, png_sBIT,
+#     ifdef PNG_READ_sBIT_SUPPORTED
+         0,
+#     else
+         1,
+#     endif
+      1,  START, 0 },
+   { "sCAL", PNG_INFO_sCAL, png_sCAL,
+#     ifdef PNG_READ_sCAL_SUPPORTED
+         0,
+#     else
+         1,
+#     endif
+      1,  START, 0 },
+   { "sPLT", PNG_INFO_sPLT, png_sPLT,
+#     ifdef PNG_READ_sPLT_SUPPORTED
+         0,
+#     else
+         1,
+#     endif
+      1, ABSENT, 0 },
+   { "sRGB", PNG_INFO_sRGB, png_sRGB,
+#     ifdef PNG_READ_sRGB_SUPPORTED
+         0,
+#     else
+         1,
+#     endif
+      1,  START, 0 },
+   { "tEXt", PNG_INFO_tEXt, png_tEXt,
+#     ifdef PNG_READ_tEXt_SUPPORTED
+         0,
+#     else
+         1,
+#     endif
+      1,  START, 0 },
+   { "tIME", PNG_INFO_tIME, png_tIME,
+#     ifdef PNG_READ_tIME_SUPPORTED
+         0,
+#     else
+         1,
+#     endif
+      1,  START, 0 },
+   { "tRNS", PNG_INFO_tRNS, png_tRNS,
+#     ifdef PNG_READ_tRNS_SUPPORTED
+         0,
+#     else
+         1,
+#     endif
+      0, ABSENT, 0 },
+   { "zTXt", PNG_INFO_zTXt, png_zTXt,
+#     ifdef PNG_READ_zTXt_SUPPORTED
+         0,
+#     else
+         1,
+#     endif
+      1,    END, 0 },
 
    /* No libpng handling */
    { "sTER", PNG_INFO_sTER, png_sTER, 1, 1,  START, 0 },
@@ -955,6 +1060,7 @@ main(void)
 {
    fprintf(stderr,
    " test ignored because libpng was not built with unknown chunk support\n");
-   return 0;
+   /* So the test is skipped: */
+   return 77;
 }
 #endif

contrib/libtests/pngvalid.c

@@ -1,8 +1,8 @@
 
 /* pngvalid.c - validate libpng by constructing then reading png files.
  *
- * Last changed in libpng 1.6.0 [(PENDING RELEASE)]
- * Copyright (c) 2012 Glenn Randers-Pehrson
+ * Last changed in libpng 1.6.1 [March 28, 2013]
+ * Copyright (c) 2013 Glenn Randers-Pehrson
  * Written by John Cunningham Bowler
  *
  * This code is released under the libpng license.
@@ -26,7 +26,7 @@
 #include <signal.h>
 #include <stdio.h>
 
-#if (defined HAVE_CONFIG_H) && !(defined PNG_NO_CONFIG_H)
+#if defined(HAVE_CONFIG_H) && !defined(PNG_NO_CONFIG_H)
 #  include <config.h>
 #endif
 
@@ -39,10 +39,8 @@
  */
 #ifdef PNG_FREESTANDING_TESTS
 #  include <png.h>
-#  include <zlib.h>   /* For crc32 */
 #else
 #  include "../../png.h"
-#  include PNG_ZLIB_HEADER
 #endif
 
 #ifdef PNG_WRITE_SUPPORTED /* else pngvalid can do nothing */
@@ -90,6 +88,8 @@ typedef png_byte *png_const_bytep;
 #  define png_const_structp png_structp
 #endif
 
+#include <zlib.h>   /* For crc32 */
+
 #include <float.h>  /* For floating point constants */
 #include <stdlib.h> /* For malloc */
 #include <string.h> /* For memcpy, memset */
@@ -344,16 +344,11 @@ standard_name_from_id(char *buffer, size_t bufsize, size_t pos, png_uint_32 id)
 
 static int
 next_format(png_bytep colour_type, png_bytep bit_depth,
-   unsigned int* palette_number, int no_low_depth_gray)
+   unsigned int* palette_number)
 {
    if (*bit_depth == 0)
    {
-      *colour_type = 0;
-      if (no_low_depth_gray)
-         *bit_depth = 8;
-      else
-         *bit_depth = 1;
-      *palette_number = 0;
+      *colour_type = 0, *bit_depth = 1, *palette_number = 0;
       return 1;
    }
 
@@ -1833,7 +1828,6 @@ typedef struct png_modifier
    double                   maxout16; /* Maximum output value error */
    double                   maxabs16; /* Absolute sample error 0..1 */
    double                   maxcalc16;/* Absolute sample error 0..1 */
-   double                   maxcalcG; /* Absolute sample error 0..1 */
    double                   maxpc16;  /* Percentage sample error 0..100% */
 
    /* This is set by transforms that need to allow a higher limit, it is an
@@ -1873,15 +1867,10 @@ typedef struct png_modifier
    /* Run the odd-sized image and interlace read/write tests? */
    unsigned int             test_size :1;
 
-   /* Run tests on reading with a combination of transforms, */
+   /* Run tests on reading with a combiniation of transforms, */
    unsigned int             test_transform :1;
 
-   /* When to use the use_input_precision option, this controls the gamma
-    * validation code checks.  If set any value that is within the transformed
-    * range input-.5 to input+.5 will be accepted, otherwise the value must be
-    * within the normal limits.  It should not be necessary to set this; the
-    * result should always be exact within the permitted error limits.
-    */
+   /* When to use the use_input_precision option: */
    unsigned int             use_input_precision :1;
    unsigned int             use_input_precision_sbit :1;
    unsigned int             use_input_precision_16to8 :1;
@@ -1891,8 +1880,8 @@ typedef struct png_modifier
     */
    unsigned int             calculations_use_input_precision :1;
 
-   /* If set assume that the calculations are done in 16 bits even if the sample
-    * depth is 8 bits.
+   /* If set assume that the calculations are done in 16 bits even if both input
+    * and output are 8 bit or less.
     */
    unsigned int             assume_16_bit_calculations :1;
 
@@ -1947,7 +1936,6 @@ modifier_init(png_modifier *pm)
    pm->test_uses_encoding = 0;
    pm->maxout8 = pm->maxpc8 = pm->maxabs8 = pm->maxcalc8 = 0;
    pm->maxout16 = pm->maxpc16 = pm->maxabs16 = pm->maxcalc16 = 0;
-   pm->maxcalcG = 0;
    pm->limit = 4E-3;
    pm->log8 = pm->log16 = 0; /* Means 'off' */
    pm->error_gray_2 = pm->error_gray_4 = pm->error_gray_8 = 0;
@@ -1962,7 +1950,6 @@ modifier_init(png_modifier *pm)
    pm->use_input_precision_sbit = 0;
    pm->use_input_precision_16to8 = 0;
    pm->calculations_use_input_precision = 0;
-   pm->assume_16_bit_calculations = 0;
    pm->test_gamma_threshold = 0;
    pm->test_gamma_transform = 0;
    pm->test_gamma_sbit = 0;
@@ -1977,16 +1964,8 @@ modifier_init(png_modifier *pm)
 }
 
 #ifdef PNG_READ_TRANSFORMS_SUPPORTED
-
-/* This controls use of checks that explicitly know how libpng digitizes the
- * samples in calculations; setting this circumvents simple error limit checking
- * in the rgb_to_gray check, replacing it with an exact copy of the libpng 1.5
- * algorithm.
- */
-#define DIGITIZE PNG_LIBPNG_VER < 10700
-
 /* If pm->calculations_use_input_precision is set then operations will happen
- * with the precision of the input, not the precision of the output depth.
+ * with only 8 bit precision unless both the input and output bit depth are 16.
  *
  * If pm->assume_16_bit_calculations is set then even 8 bit calculations use 16
  * bit precision.  This only affects those of the following limits that pertain
@@ -1994,8 +1973,8 @@ modifier_init(png_modifier *pm)
  * called directly.
  */
 #ifdef PNG_READ_RGB_TO_GRAY_SUPPORTED
-#if DIGITIZE
-static double digitize(double value, int depth, int do_round)
+static double digitize(PNG_CONST png_modifier *pm, double value,
+   int sample_depth, int do_round)
 {
    /* 'value' is in the range 0 to 1, the result is the same value rounded to a
     * multiple of the digitization factor - 8 or 16 bits depending on both the
@@ -2003,14 +1982,14 @@ static double digitize(double value, int depth, int do_round)
     * rounding and 'do_round' should be 1, if it is 0 the digitized value will
     * be truncated.
     */
-   PNG_CONST unsigned int digitization_factor = (1U << depth) -1;
+   PNG_CONST unsigned int digitization_factor =
+      (pm->assume_16_bit_calculations || sample_depth == 16) ? 65535 : 255;
 
    /* Limiting the range is done as a convenience to the caller - it's easier to
     * do it once here than every time at the call site.
     */
    if (value <= 0)
       value = 0;
-
    else if (value >= 1)
       value = 1;
 
@@ -2019,30 +1998,31 @@ static double digitize(double value, int depth, int do_round)
    return floor(value)/digitization_factor;
 }
 #endif
-#endif /* RGB_TO_GRAY */
 
-#ifdef PNG_READ_GAMMA_SUPPORTED
+#if defined(PNG_READ_GAMMA_SUPPORTED) ||\
+   defined(PNG_READ_RGB_TO_GRAY_SUPPORTED)
 static double abserr(PNG_CONST png_modifier *pm, int in_depth, int out_depth)
 {
    /* Absolute error permitted in linear values - affected by the bit depth of
     * the calculations.
     */
-   if (pm->assume_16_bit_calculations ||
-      (pm->calculations_use_input_precision ? in_depth : out_depth) == 16)
+   if (pm->assume_16_bit_calculations || (out_depth == 16 && (in_depth == 16 ||
+      !pm->calculations_use_input_precision)))
       return pm->maxabs16;
    else
       return pm->maxabs8;
 }
+#endif
 
+#ifdef PNG_READ_GAMMA_SUPPORTED
 static double calcerr(PNG_CONST png_modifier *pm, int in_depth, int out_depth)
 {
    /* Error in the linear composition arithmetic - only relevant when
     * composition actually happens (0 < alpha < 1).
     */
-   if ((pm->calculations_use_input_precision ? in_depth : out_depth) == 16)
+   if (pm->assume_16_bit_calculations || (out_depth == 16 && (in_depth == 16 ||
+      !pm->calculations_use_input_precision)))
       return pm->maxcalc16;
-   else if (pm->assume_16_bit_calculations)
-      return pm->maxcalcG;
    else
       return pm->maxcalc8;
 }
@@ -2052,8 +2032,8 @@ static double pcerr(PNG_CONST png_modifier *pm, int in_depth, int out_depth)
    /* Percentage error permitted in the linear values.  Note that the specified
     * value is a percentage but this routine returns a simple number.
     */
-   if (pm->assume_16_bit_calculations ||
-      (pm->calculations_use_input_precision ? in_depth : out_depth) == 16)
+   if (pm->assume_16_bit_calculations || (out_depth == 16 && (in_depth == 16 ||
+      !pm->calculations_use_input_precision)))
       return pm->maxpc16 * .01;
    else
       return pm->maxpc8 * .01;
@@ -2085,7 +2065,8 @@ static double outerr(PNG_CONST png_modifier *pm, int in_depth, int out_depth)
    if (out_depth == 4)
       return .90644-.5;
 
-   if ((pm->calculations_use_input_precision ? in_depth : out_depth) == 16)
+   if (out_depth == 16 && (in_depth == 16 ||
+      !pm->calculations_use_input_precision))
       return pm->maxout16;
 
    /* This is the case where the value was calculated at 8-bit precision then
@@ -2118,7 +2099,8 @@ static double outlog(PNG_CONST png_modifier *pm, int in_depth, int out_depth)
       return pm->log8;
    }
 
-   if ((pm->calculations_use_input_precision ? in_depth : out_depth) == 16)
+   if (out_depth == 16 && (in_depth == 16 ||
+      !pm->calculations_use_input_precision))
    {
       if (pm->log16 == 0)
          return 65536;
@@ -2143,8 +2125,8 @@ static double outlog(PNG_CONST png_modifier *pm, int in_depth, int out_depth)
 static int output_quantization_factor(PNG_CONST png_modifier *pm, int in_depth,
    int out_depth)
 {
-   if (out_depth == 16 && in_depth != 16 &&
-      pm->calculations_use_input_precision)
+   if (out_depth == 16 && in_depth != 16
+      && pm->calculations_use_input_precision)
       return 257;
    else
       return 1;
@@ -3375,7 +3357,7 @@ make_transform_image(png_store* PNG_CONST ps, png_byte PNG_CONST colour_type,
          PNG_COMPRESSION_TYPE_BASE, PNG_FILTER_TYPE_BASE);
 
 #ifdef PNG_TEXT_SUPPORTED
-#  if (defined PNG_READ_zTXt_SUPPORTED) && (defined PNG_WRITE_zTXt_SUPPORTED)
+#  if defined(PNG_READ_zTXt_SUPPORTED) && defined(PNG_WRITE_zTXt_SUPPORTED)
 #     define TEXT_COMPRESSION PNG_TEXT_COMPRESSION_zTXt
 #  else
 #     define TEXT_COMPRESSION PNG_TEXT_COMPRESSION_NONE
@@ -3491,7 +3473,7 @@ make_transform_images(png_store *ps)
    /* Use next_format to enumerate all the combinations we test, including
     * generating multiple low bit depth palette images.
     */
-   while (next_format(&colour_type, &bit_depth, &palette_number, 0))
+   while (next_format(&colour_type, &bit_depth, &palette_number))
    {
       int interlace_type;
 
@@ -4617,9 +4599,13 @@ progressive_row(png_structp ppIn, png_bytep new_row, png_uint_32 y, int pass)
       }
       else
          png_progressive_combine_row(pp, row, new_row);
-   } else if (dp->interlace_type == PNG_INTERLACE_ADAM7 &&
-      PNG_ROW_IN_INTERLACE_PASS(y, pass) &&
-      PNG_PASS_COLS(dp->w, pass) > 0)
+#endif /* PNG_READ_INTERLACING_SUPPORTED */
+   }
+
+#ifdef PNG_READ_INTERLACING_SUPPORTED
+   else if (dp->interlace_type == PNG_INTERLACE_ADAM7 &&
+       PNG_ROW_IN_INTERLACE_PASS(y, pass) &&
+       PNG_PASS_COLS(dp->w, pass) > 0)
       png_error(pp, "missing row in progressive de-interlacing");
 #endif /* PNG_READ_INTERLACING_SUPPORTED */
 }
@@ -5802,9 +5788,12 @@ transform_image_validate(transform_display *dp, png_const_structp pp,
 
       memset(out_palette, 0x5e, sizeof out_palette);
 
-      /* use-input-precision means assume that if the input has 8 bit (or less)
-       * samples and the output has 16 bit samples the calculations will be done
-       * with 8 bit precision, not 16.
+      /* assume-8-bit-calculations means assume that if the input has 8 bit
+       * (or less) samples and the output has 16 bit samples the calculations
+       * will be done with 8 bit precision, not 16.
+       *
+       * TODO: fix this in libpng; png_set_expand_16 should cause 16 bit
+       * calculations to be used throughout.
        */
       if (in_ct == PNG_COLOR_TYPE_PALETTE || in_bd < 16)
          in_sample_depth = 8;
@@ -5815,8 +5804,7 @@ transform_image_validate(transform_display *dp, png_const_structp pp,
          !dp->pm->calculations_use_input_precision)
          digitization_error = .5;
 
-      /* Else calculations are at 8 bit precision, and the output actually
-       * consists of scaled 8-bit values, so scale .5 in 8 bits to the 16 bits:
+      /* Else errors are at 8 bit precision, scale .5 in 8 bits to the 16 bits:
        */
       else
          digitization_error = .5 * 257;
@@ -6632,23 +6620,10 @@ image_transform_png_set_rgb_to_gray_ini(PNG_CONST image_transform *this,
    {
       if (that->this.bit_depth == 16 || pm->assume_16_bit_calculations)
       {
-         /* The computations have the form:
-          *
-          *    r * rc + g * gc + b * bc
-          *
-          *  Each component of which is +/-1/65535 from the gamma_to_1 table
-          *  lookup, resulting in a base error of +/-6.  The gamma_from_1
-          *  conversion adds another +/-2 in the 16-bit case and
-          *  +/-(1<<(15-PNG_MAX_GAMMA_8)) in the 8-bit case.
+         /* The 16 bit case ends up producing a maximum error of about
+          * +/-5 in 65535, allow for +/-8 with the given gamma.
           */
-         that->pm->limit += pow(
-#           if PNG_MAX_GAMMA_8 < 14
-               (that->this.bit_depth == 16 ? 8. :
-                  6. + (1<<(15-PNG_MAX_GAMMA_8)))
-#           else
-               8.
-#           endif
-               /65535, data.gamma);
+         that->pm->limit += pow(8./65535, data.gamma);
       }
 
       else
@@ -6666,7 +6641,7 @@ image_transform_png_set_rgb_to_gray_ini(PNG_CONST image_transform *this,
       /* With no gamma correction a large error comes from the truncation of the
        * calculation in the 8 bit case, allow for that here.
        */
-      if (that->this.bit_depth != 16 && !pm->assume_16_bit_calculations)
+      if (that->this.bit_depth != 16)
          that->pm->limit += 4E-3;
    }
 }
@@ -6811,14 +6786,9 @@ image_transform_png_set_rgb_to_gray_mod(PNG_CONST image_transform *this,
          image_pixel_convert_PLTE(that);
 
       /* Image now has RGB channels... */
-#  if DIGITIZE
       {
          PNG_CONST png_modifier *pm = display->pm;
-         const unsigned int sample_depth = that->sample_depth;
-         const unsigned int calc_depth = (pm->assume_16_bit_calculations ? 16 :
-            sample_depth);
-         const unsigned int gamma_depth = (sample_depth == 16 ? 16 :
-            (pm->assume_16_bit_calculations ? PNG_MAX_GAMMA_8 : sample_depth));
+         PNG_CONST unsigned int sample_depth = that->sample_depth;
          int isgray;
          double r, g, b;
          double rlo, rhi, glo, ghi, blo, bhi, graylo, grayhi;
@@ -6834,28 +6804,28 @@ image_transform_png_set_rgb_to_gray_mod(PNG_CONST image_transform *this,
           */
          r = rlo = rhi = that->redf;
          rlo -= that->rede;
-         rlo = digitize(rlo, calc_depth, 1/*round*/);
+         rlo = digitize(pm, rlo, sample_depth, 1/*round*/);
          rhi += that->rede;
-         rhi = digitize(rhi, calc_depth, 1/*round*/);
+         rhi = digitize(pm, rhi, sample_depth, 1/*round*/);
 
          g = glo = ghi = that->greenf;
          glo -= that->greene;
-         glo = digitize(glo, calc_depth, 1/*round*/);
+         glo = digitize(pm, glo, sample_depth, 1/*round*/);
          ghi += that->greene;
-         ghi = digitize(ghi, calc_depth, 1/*round*/);
+         ghi = digitize(pm, ghi, sample_depth, 1/*round*/);
 
          b = blo = bhi = that->bluef;
          blo -= that->bluee;
-         blo = digitize(blo, calc_depth, 1/*round*/);
+         blo = digitize(pm, blo, sample_depth, 1/*round*/);
          bhi += that->greene;
-         bhi = digitize(bhi, calc_depth, 1/*round*/);
+         bhi = digitize(pm, bhi, sample_depth, 1/*round*/);
 
          isgray = r==g && g==b;
 
          if (data.gamma != 1)
          {
             PNG_CONST double power = 1/data.gamma;
-            PNG_CONST double abse = calc_depth == 16 ? .5/65535 : .5/255;
+            PNG_CONST double abse = abserr(pm, sample_depth, sample_depth);
 
             /* 'abse' is the absolute error permitted in linear calculations. It
              * is used here to capture the error permitted in the handling
@@ -6864,16 +6834,16 @@ image_transform_png_set_rgb_to_gray_mod(PNG_CONST image_transform *this,
              * where the real errors are introduced.
              */
             r = pow(r, power);
-            rlo = digitize(pow(rlo, power)-abse, calc_depth, 1);
-            rhi = digitize(pow(rhi, power)+abse, calc_depth, 1);
+            rlo = digitize(pm, pow(rlo, power)-abse, sample_depth, 1);
+            rhi = digitize(pm, pow(rhi, power)+abse, sample_depth, 1);
 
             g = pow(g, power);
-            glo = digitize(pow(glo, power)-abse, calc_depth, 1);
-            ghi = digitize(pow(ghi, power)+abse, calc_depth, 1);
+            glo = digitize(pm, pow(glo, power)-abse, sample_depth, 1);
+            ghi = digitize(pm, pow(ghi, power)+abse, sample_depth, 1);
 
             b = pow(b, power);
-            blo = digitize(pow(blo, power)-abse, calc_depth, 1);
-            bhi = digitize(pow(bhi, power)+abse, calc_depth, 1);
+            blo = digitize(pm, pow(blo, power)-abse, sample_depth, 1);
+            bhi = digitize(pm, pow(bhi, power)+abse, sample_depth, 1);
          }
 
          /* Now calculate the actual gray values.  Although the error in the
@@ -6890,18 +6860,18 @@ image_transform_png_set_rgb_to_gray_mod(PNG_CONST image_transform *this,
             b * data.blue_coefficient;
 
          {
-            PNG_CONST int do_round = data.gamma != 1 || calc_depth == 16;
+            PNG_CONST int do_round = data.gamma != 1 || sample_depth == 16;
             PNG_CONST double ce = 1. / 32768;
 
-            graylo = digitize(rlo * (data.red_coefficient-ce) +
+            graylo = digitize(pm, rlo * (data.red_coefficient-ce) +
                glo * (data.green_coefficient-ce) +
-               blo * (data.blue_coefficient-ce), gamma_depth, do_round);
+               blo * (data.blue_coefficient-ce), sample_depth, do_round);
             if (graylo <= 0)
                graylo = 0;
 
-            grayhi = digitize(rhi * (data.red_coefficient+ce) +
+            grayhi = digitize(pm, rhi * (data.red_coefficient+ce) +
                ghi * (data.green_coefficient+ce) +
-               bhi * (data.blue_coefficient+ce), gamma_depth, do_round);
+               bhi * (data.blue_coefficient+ce), sample_depth, do_round);
             if (grayhi >= 1)
                grayhi = 1;
          }
@@ -6912,8 +6882,8 @@ image_transform_png_set_rgb_to_gray_mod(PNG_CONST image_transform *this,
             PNG_CONST double power = data.gamma;
 
             gray = pow(gray, power);
-            graylo = digitize(pow(graylo, power), sample_depth, 1);
-            grayhi = digitize(pow(grayhi, power), sample_depth, 1);
+            graylo = digitize(pm, pow(graylo, power), sample_depth, 1);
+            grayhi = digitize(pm, pow(grayhi, power), sample_depth, 1);
          }
 
          /* Now the error can be calculated.
@@ -6931,7 +6901,7 @@ image_transform_png_set_rgb_to_gray_mod(PNG_CONST image_transform *this,
                err = fabs(graylo-gray);
 
             /* Check that this worked: */
-            if (err > pm->limit)
+            if (err > display->pm->limit)
             {
                size_t pos = 0;
                char buffer[128];
@@ -6939,120 +6909,12 @@ image_transform_png_set_rgb_to_gray_mod(PNG_CONST image_transform *this,
                pos = safecat(buffer, sizeof buffer, pos, "rgb_to_gray error ");
                pos = safecatd(buffer, sizeof buffer, pos, err, 6);
                pos = safecat(buffer, sizeof buffer, pos, " exceeds limit ");
-               pos = safecatd(buffer, sizeof buffer, pos, pm->limit, 6);
+               pos = safecatd(buffer, sizeof buffer, pos,
+                  display->pm->limit, 6);
                png_error(pp, buffer);
             }
          }
       }
-#  else  /* DIGITIZE */
-      {
-         double r = that->redf;
-         double re = that->rede;
-         double g = that->greenf;
-         double ge = that->greene;
-         double b = that->bluef;
-         double be = that->bluee;
-
-         /* The true gray case involves no math. */
-         if (r == g && r == b)
-         {
-            gray = r;
-            err = re;
-            if (err < ge) err = ge;
-            if (err < be) err = be;
-         }
-
-         else if (data.gamma == 1)
-         {
-            /* There is no need to do the conversions to and from linear space,
-             * so the calculation should be a lot more accurate.  There is a
-             * built in 1/32768 error in the coefficients because they only have
-             * 15 bits and are adjusted to make sure they add up to 32768, so
-             * the result may have an additional error up to 1/32768.  (Note
-             * that adding the 1/32768 here avoids needing to increase the
-             * global error limits to take this into account.)
-             */
-            gray = r * data.red_coefficient + g * data.green_coefficient +
-               b * data.blue_coefficient;
-            err = re * data.red_coefficient + ge * data.green_coefficient +
-               be * data.blue_coefficient + 1./32768 + gray * 5 * DBL_EPSILON;
-         }
-
-         else
-         {
-            /* The calculation happens in linear space, and this produces much
-             * wider errors in the encoded space.  These are handled here by
-             * factoring the errors in to the calculation.  There are two table
-             * lookups in the calculation and each introduces a quantization
-             * error defined by the table size.
-             */
-            PNG_CONST png_modifier *pm = display->pm;
-            double in_qe = (that->sample_depth > 8 ? .5/65535 : .5/255);
-            double out_qe = (that->sample_depth > 8 ? .5/65535 :
-               (pm->assume_16_bit_calculations ? .5/(1<<PNG_MAX_GAMMA_8) :
-               .5/255));
-            double rhi, ghi, bhi, grayhi;
-            double g1 = 1/data.gamma;
-
-            rhi = r + re + in_qe; if (rhi > 1) rhi = 1;
-            r -= re + in_qe; if (r < 0) r = 0;
-            ghi = g + ge + in_qe; if (ghi > 1) ghi = 1;
-            g -= ge + in_qe; if (g < 0) g = 0;
-            bhi = b + be + in_qe; if (bhi > 1) bhi = 1;
-            b -= be + in_qe; if (b < 0) b = 0;
-
-            r = pow(r, g1)*(1-DBL_EPSILON); rhi = pow(rhi, g1)*(1+DBL_EPSILON);
-            g = pow(g, g1)*(1-DBL_EPSILON); ghi = pow(ghi, g1)*(1+DBL_EPSILON);
-            b = pow(b, g1)*(1-DBL_EPSILON); bhi = pow(bhi, g1)*(1+DBL_EPSILON);
-
-            /* Work out the lower and upper bounds for the gray value in the
-             * encoded space, then work out an average and error.  Remove the
-             * previously added input quantization error at this point.
-             */
-            gray = r * data.red_coefficient + g * data.green_coefficient +
-               b * data.blue_coefficient - 1./32768 - out_qe;
-            if (gray <= 0)
-               gray = 0;
-            else
-            {
-               gray *= (1 - 6 * DBL_EPSILON);
-               gray = pow(gray, data.gamma) * (1-DBL_EPSILON);
-            }
-
-            grayhi = rhi * data.red_coefficient + ghi * data.green_coefficient +
-               bhi * data.blue_coefficient + 1./32768 + out_qe;
-            grayhi *= (1 + 6 * DBL_EPSILON);
-            if (grayhi >= 1)
-               grayhi = 1;
-            else
-               grayhi = pow(grayhi, data.gamma) * (1+DBL_EPSILON);
-
-            err = (grayhi - gray) / 2;
-            gray = (grayhi + gray) / 2;
-
-            if (err <= in_qe)
-               err = gray * DBL_EPSILON;
-
-            else
-               err -= in_qe;
-
-            /* Validate that the error is within limits (this has caused
-             * problems before, it's much easier to detect them here.)
-             */
-            if (err > pm->limit)
-            {
-               size_t pos = 0;
-               char buffer[128];
-
-               pos = safecat(buffer, sizeof buffer, pos, "rgb_to_gray error ");
-               pos = safecatd(buffer, sizeof buffer, pos, err, 6);
-               pos = safecat(buffer, sizeof buffer, pos, " exceeds limit ");
-               pos = safecatd(buffer, sizeof buffer, pos, pm->limit, 6);
-               png_error(pp, buffer);
-            }
-         }
-      }
-#  endif /* !DIGITIZE */
 
       that->bluef = that->greenf = that->redf = gray;
       that->bluee = that->greene = that->rede = err;
@@ -7101,7 +6963,7 @@ IT(rgb_to_gray);
  *    int background_gamma_code, int need_expand,
  *    png_fixed_point background_gamma)
  *
- * This ignores the gamma (at present.)
+ * As with rgb_to_gray this ignores the gamma (at present.)
 */
 #define data ITDATA(background)
 static image_pixel data;
@@ -7112,7 +6974,6 @@ image_transform_png_set_background_set(PNG_CONST image_transform *this,
 {
    png_byte colour_type, bit_depth;
    png_byte random_bytes[8]; /* 8 bytes - 64 bits - the biggest pixel */
-   int expand;
    png_color_16 back;
 
    /* We need a background colour, because we don't know exactly what transforms
@@ -7130,14 +6991,10 @@ image_transform_png_set_background_set(PNG_CONST image_transform *this,
    {
       colour_type = PNG_COLOR_TYPE_RGB;
       bit_depth = 8;
-      expand = 0; /* passing in an RGB not a pixel index */
    }
 
    else
-   {
       bit_depth = that->this.bit_depth;
-      expand = 1;
-   }
 
    image_pixel_init(&data, random_bytes, colour_type,
       bit_depth, 0/*x*/, 0/*unused: palette*/);
@@ -7158,9 +7015,11 @@ image_transform_png_set_background_set(PNG_CONST image_transform *this,
       back.gray = (png_uint_16)data.red;
 
 #  ifdef PNG_FLOATING_POINT_SUPPORTED
-      png_set_background(pp, &back, PNG_BACKGROUND_GAMMA_FILE, expand, 0);
+      png_set_background(pp, &back, PNG_BACKGROUND_GAMMA_FILE, 1/*need expand*/,
+         0);
 #  else
-      png_set_background_fixed(pp, &back, PNG_BACKGROUND_GAMMA_FILE, expand, 0);
+      png_set_background_fixed(pp, &back, PNG_BACKGROUND_GAMMA_FILE,
+         1/*need expand*/, 0);
 #  endif
 
    this->next->set(this->next, that, pp, pi);
@@ -7492,7 +7351,7 @@ perform_transform_test(png_modifier *pm)
    png_byte bit_depth = 0;
    unsigned int palette_number = 0;
 
-   while (next_format(&colour_type, &bit_depth, &palette_number, 0))
+   while (next_format(&colour_type, &bit_depth, &palette_number))
    {
       png_uint_32 counter = 0;
       size_t base_pos;
@@ -8177,25 +8036,14 @@ gamma_component_validate(PNG_CONST char *name, PNG_CONST validate_info *vi,
           * passed.  Don't do these additional tests here - just log the
           * original [es_lo..es_hi] values.
           */
-         if (pass == 0 && vi->use_input_precision && vi->dp->sbit)
+         if (pass == 0 && vi->use_input_precision)
          {
             /* Ok, something is wrong - this actually happens in current libpng
              * 16-to-8 processing.  Assume that the input value (id, adjusted
              * for sbit) can be anywhere between value-.5 and value+.5 - quite a
              * large range if sbit is low.
-             *
-             * NOTE: at present because the libpng gamma table stuff has been
-             * changed to use a rounding algorithm to correct errors in 8-bit
-             * calculations the precise sbit calculation (a shift) has been
-             * lost.  This can result in up to a +/-1 error in the presence of
-             * an sbit less than the bit depth.
              */
-#           if PNG_LIBPNG_VER < 10700
-#              define SBIT_ERROR .5
-#           else
-#              define SBIT_ERROR 1.
-#           endif
-            double tmp = (isbit - SBIT_ERROR)/sbit_max;
+            double tmp = (isbit - .5)/sbit_max;
 
             if (tmp <= 0)
                tmp = 0;
@@ -8214,10 +8062,10 @@ gamma_component_validate(PNG_CONST char *name, PNG_CONST validate_info *vi,
             if (is_lo < 0)
                is_lo = 0;
 
-            tmp = (isbit + SBIT_ERROR)/sbit_max;
+            tmp = (isbit + .5)/sbit_max;
 
-            if (tmp >= 1)
-               tmp = 1;
+            if (tmp <= 0)
+               tmp = 0;
 
             else if (alpha >= 0 && vi->file_inverse > 0 && tmp < 1)
                tmp = pow(tmp, vi->file_inverse);
@@ -8534,7 +8382,7 @@ gamma_image_validate(gamma_display *dp, png_const_structp pp,
     * Because there is limited precision in the input it is arguable that
     * an acceptable result is any valid result from input-.5 to input+.5.
     * The basic tests below do not do this, however if 'use_input_precision'
-    * is set a subsequent test is performed above.
+    * is set a subsequent test is performed below.
     */
    PNG_CONST unsigned int samples_per_pixel = (out_ct & 2U) ? 3U : 1U;
    int processing;
@@ -8876,7 +8724,7 @@ perform_gamma_threshold_tests(png_modifier *pm)
     * fact this test is somewhat excessive since libpng doesn't make this
     * decision based on colour type or bit depth!
     */
-   while (next_format(&colour_type, &bit_depth, &palette_number, 1/*gamma*/))
+   while (next_format(&colour_type, &bit_depth, &palette_number))
       if (palette_number == 0)
    {
       double test_gamma = 1.0;
@@ -8937,7 +8785,7 @@ static void perform_gamma_transform_tests(png_modifier *pm)
    png_byte bit_depth = 0;
    unsigned int palette_number = 0;
 
-   while (next_format(&colour_type, &bit_depth, &palette_number, 1/*gamma*/))
+   while (next_format(&colour_type, &bit_depth, &palette_number))
    {
       unsigned int i, j;
 
@@ -8967,7 +8815,7 @@ static void perform_gamma_sbit_tests(png_modifier *pm)
       png_byte colour_type = 0, bit_depth = 0;
       unsigned int npalette = 0;
 
-      while (next_format(&colour_type, &bit_depth, &npalette, 1/*gamma*/))
+      while (next_format(&colour_type, &bit_depth, &npalette))
          if ((colour_type & PNG_COLOR_MASK_ALPHA) == 0 &&
             ((colour_type == 3 && sbit < 8) ||
             (colour_type != 3 && sbit < bit_depth)))
@@ -9002,7 +8850,6 @@ static void perform_gamma_scale16_tests(png_modifier *pm)
 #  ifndef PNG_MAX_GAMMA_8
 #     define PNG_MAX_GAMMA_8 11
 #  endif
-#  define SBIT_16_TO_8 PNG_MAX_GAMMA_8
    /* Include the alpha cases here. Note that sbit matches the internal value
     * used by the library - otherwise we will get spurious errors from the
     * internal sbit style approximation.
@@ -9020,28 +8867,28 @@ static void perform_gamma_scale16_tests(png_modifier *pm)
              fabs(pm->gammas[j]/pm->gammas[i]-1) >= PNG_GAMMA_THRESHOLD)
          {
             gamma_transform_test(pm, 0, 16, 0, pm->interlace_type,
-               1/pm->gammas[i], pm->gammas[j], SBIT_16_TO_8,
+               1/pm->gammas[i], pm->gammas[j], PNG_MAX_GAMMA_8,
                pm->use_input_precision_16to8, 1 /*scale16*/);
 
             if (fail(pm))
                return;
 
             gamma_transform_test(pm, 2, 16, 0, pm->interlace_type,
-               1/pm->gammas[i], pm->gammas[j], SBIT_16_TO_8,
+               1/pm->gammas[i], pm->gammas[j], PNG_MAX_GAMMA_8,
                pm->use_input_precision_16to8, 1 /*scale16*/);
 
             if (fail(pm))
                return;
 
             gamma_transform_test(pm, 4, 16, 0, pm->interlace_type,
-               1/pm->gammas[i], pm->gammas[j], SBIT_16_TO_8,
+               1/pm->gammas[i], pm->gammas[j], PNG_MAX_GAMMA_8,
                pm->use_input_precision_16to8, 1 /*scale16*/);
 
             if (fail(pm))
                return;
 
             gamma_transform_test(pm, 6, 16, 0, pm->interlace_type,
-               1/pm->gammas[i], pm->gammas[j], SBIT_16_TO_8,
+               1/pm->gammas[i], pm->gammas[j], PNG_MAX_GAMMA_8,
                pm->use_input_precision_16to8, 1 /*scale16*/);
 
             if (fail(pm))
@@ -9052,8 +8899,8 @@ static void perform_gamma_scale16_tests(png_modifier *pm)
 }
 #endif /* 16 to 8 bit conversion */
 
-#if defined PNG_READ_BACKGROUND_SUPPORTED ||\
-   defined PNG_READ_ALPHA_MODE_SUPPORTED
+#if defined(PNG_READ_BACKGROUND_SUPPORTED) ||\
+   defined(PNG_READ_ALPHA_MODE_SUPPORTED)
 static void gamma_composition_test(png_modifier *pm,
    PNG_CONST png_byte colour_type, PNG_CONST png_byte bit_depth,
    PNG_CONST int palette_number,
@@ -9187,7 +9034,7 @@ perform_gamma_composition_tests(png_modifier *pm, int do_background,
    /* Skip the non-alpha cases - there is no setting of a transparency colour at
     * present.
     */
-   while (next_format(&colour_type, &bit_depth, &palette_number, 1/*gamma*/))
+   while (next_format(&colour_type, &bit_depth, &palette_number))
       if ((colour_type & PNG_COLOR_MASK_ALPHA) != 0)
    {
       unsigned int i, j;
@@ -9209,46 +9056,31 @@ perform_gamma_composition_tests(png_modifier *pm, int do_background,
 static void
 init_gamma_errors(png_modifier *pm)
 {
-   /* Use -1 to catch tests that were not actually run */
-   pm->error_gray_2 = pm->error_gray_4 = pm->error_gray_8 = -1.;
-   pm->error_color_8 = -1.;
-   pm->error_indexed = -1.;
-   pm->error_gray_16 = pm->error_color_16 = -1.;
+   pm->error_gray_2 = pm->error_gray_4 = pm->error_gray_8 = 0;
+   pm->error_color_8 = 0;
+   pm->error_indexed = 0;
+   pm->error_gray_16 = pm->error_color_16 = 0;
 }
 
 static void
-print_one(const char *leader, double err)
+summarize_gamma_errors(png_modifier *pm, png_const_charp who, int low_bit_depth)
 {
-   if (err != -1.)
-      printf(" %s %.5f\n", leader, err);
-}
-
-static void
-summarize_gamma_errors(png_modifier *pm, png_const_charp who, int low_bit_depth,
-   int indexed)
-{
-   fflush(stderr);
-
    if (who)
-      printf("\nGamma correction with %s:\n", who);
-
-   else
-      printf("\nBasic gamma correction:\n");
+      printf("Gamma correction with %s:\n", who);
 
    if (low_bit_depth)
    {
-      print_one(" 2 bit gray: ", pm->error_gray_2);
-      print_one(" 4 bit gray: ", pm->error_gray_4);
-      print_one(" 8 bit gray: ", pm->error_gray_8);
-      print_one(" 8 bit color:", pm->error_color_8);
-      if (indexed)
-         print_one(" indexed:    ", pm->error_indexed);
+      printf("  2 bit gray:  %.5f\n", pm->error_gray_2);
+      printf("  4 bit gray:  %.5f\n", pm->error_gray_4);
+      printf("  8 bit gray:  %.5f\n", pm->error_gray_8);
+      printf("  8 bit color: %.5f\n", pm->error_color_8);
+      printf("  indexed:     %.5f\n", pm->error_indexed);
    }
 
-   print_one("16 bit gray: ", pm->error_gray_16);
-   print_one("16 bit color:", pm->error_color_16);
-
-   fflush(stdout);
+#ifdef DO_16BIT
+   printf(" 16 bit gray:  %.5f\n", pm->error_gray_16);
+   printf(" 16 bit color: %.5f\n", pm->error_color_16);
+#endif
 }
 
 static void
@@ -9274,24 +9106,6 @@ perform_gamma_test(png_modifier *pm, int summary)
    /* Now some real transforms. */
    if (pm->test_gamma_transform)
    {
-      if (summary)
-      {
-         fflush(stderr);
-         printf("Gamma correction error summary\n\n");
-         printf("The printed value is the maximum error in the pixel values\n");
-         printf("calculated by the libpng gamma correction code.  The error\n");
-         printf("is calculated as the difference between the output pixel\n");
-         printf("value (always an integer) and the ideal value from the\n");
-         printf("libpng specification (typically not an integer).\n\n");
-
-         printf("Expect this value to be less than .5 for 8 bit formats,\n");
-         printf("less than 1 for formats with fewer than 8 bits and a small\n");
-         printf("number (typically less than 5) for the 16 bit formats.\n");
-         printf("For performance reasons the value for 16 bit formats\n");
-         printf("increases when the image file includes an sBIT chunk.\n");
-         fflush(stdout);
-      }
-
       init_gamma_errors(pm);
       /*TODO: remove this.  Necessary because the current libpng
        * implementation works in 8 bits:
@@ -9303,10 +9117,22 @@ perform_gamma_test(png_modifier *pm, int summary)
          pm->calculations_use_input_precision = 0;
 
       if (summary)
-         summarize_gamma_errors(pm, 0/*who*/, 1/*low bit depth*/, 1/*indexed*/);
+      {
+         printf("Gamma correction error summary\n\n");
+         printf("The printed value is the maximum error in the pixel values\n");
+         printf("calculated by the libpng gamma correction code.  The error\n");
+         printf("is calculated as the difference between the output pixel\n");
+         printf("value (always an integer) and the ideal value from the\n");
+         printf("libpng specification (typically not an integer).\n\n");
 
-      if (fail(pm))
-         return;
+         printf("Expect this value to be less than .5 for 8 bit formats,\n");
+         printf("less than 1 for formats with fewer than 8 bits and a small\n");
+         printf("number (typically less than 5) for the 16 bit formats.\n");
+         printf("For performance reasons the value for 16 bit formats\n");
+         printf("increases when the image file includes an sBIT chunk.\n\n");
+
+         summarize_gamma_errors(pm, 0/*who*/, 1);
+      }
    }
 
    /* The sbit tests produce much larger errors: */
@@ -9316,10 +9142,7 @@ perform_gamma_test(png_modifier *pm, int summary)
       perform_gamma_sbit_tests(pm);
 
       if (summary)
-         summarize_gamma_errors(pm, "sBIT", pm->sbitlow < 8U, 1/*indexed*/);
-
-      if (fail(pm))
-         return;
+         summarize_gamma_errors(pm, "sBIT", pm->sbitlow < 8U);
    }
 
 #ifdef DO_16BIT /* Should be READ_16BIT_SUPPORTED */
@@ -9331,15 +9154,10 @@ perform_gamma_test(png_modifier *pm, int summary)
 
       if (summary)
       {
-         fflush(stderr);
-         printf("\nGamma correction with 16 to 8 bit reduction:\n");
+         printf("Gamma correction with 16 to 8 bit reduction:\n");
          printf(" 16 bit gray:  %.5f\n", pm->error_gray_16);
          printf(" 16 bit color: %.5f\n", pm->error_color_16);
-         fflush(stdout);
       }
-
-      if (fail(pm))
-         return;
    }
 #endif
 
@@ -9363,10 +9181,7 @@ perform_gamma_test(png_modifier *pm, int summary)
       pm->maxout8 = maxout8;
 
       if (summary)
-         summarize_gamma_errors(pm, "background", 1, 0/*indexed*/);
-
-      if (fail(pm))
-         return;
+         summarize_gamma_errors(pm, "background", 1);
    }
 #endif
 
@@ -9391,10 +9206,7 @@ perform_gamma_test(png_modifier *pm, int summary)
          pm->calculations_use_input_precision = 0;
 
       if (summary)
-         summarize_gamma_errors(pm, "alpha mode", 1, 0/*indexed*/);
-
-      if (fail(pm))
-         return;
+         summarize_gamma_errors(pm, "alpha mode", 1);
    }
 #endif
 }
@@ -9902,19 +9714,6 @@ int main(int argc, char **argv)
    /* Default to error on warning: */
    pm.this.treat_warnings_as_errors = 1;
 
-   /* Default assume_16_bit_calculations appropriately; this tells the checking
-    * code that 16-bit arithmetic is used for 8-bit samples when it would make a
-    * difference.
-    */
-   pm.assume_16_bit_calculations = PNG_LIBPNG_VER >= 10700;
-
-   /* Currently 16 bit expansion happens at the end of the pipeline, so the
-    * calculations are done in the input bit depth not the output.
-    *
-    * TODO: fix this
-    */
-   pm.calculations_use_input_precision = 1U;
-
    /* Store the test gammas */
    pm.gammas = gammas;
    pm.ngammas = (sizeof gammas) / (sizeof gammas[0]);
@@ -9925,16 +9724,13 @@ int main(int argc, char **argv)
    pm.nencodings = (sizeof test_encodings) / (sizeof test_encodings[0]);
 
    pm.sbitlow = 8U; /* because libpng doesn't do sBIT below 8! */
-
    /* The following allows results to pass if they correspond to anything in the
     * transformed range [input-.5,input+.5]; this is is required because of the
-    * way libpng treates the 16_TO_8 flag when building the gamma tables in
-    * releases up to 1.6.0.
+    * way libpng treates the 16_TO_8 flag when building the gamma tables.
     *
     * TODO: review this
     */
    pm.use_input_precision_16to8 = 1U;
-   pm.use_input_precision_sbit = 1U; /* because libpng now rounds sBIT */
 
    /* Some default values (set the behavior for 'make check' here).
     * These values simply control the maximum error permitted in the gamma
@@ -9945,12 +9741,11 @@ int main(int argc, char **argv)
     */
    pm.maxout8 = .1;     /* Arithmetic error in *encoded* value */
    pm.maxabs8 = .00005; /* 1/20000 */
-   pm.maxcalc8 = 1./255;  /* +/-1 in 8 bits for compose errors */
+   pm.maxcalc8 = .004;  /* +/-1 in 8 bits for compose errors */
    pm.maxpc8 = .499;    /* I.e., .499% fractional error */
    pm.maxout16 = .499;  /* Error in *encoded* value */
    pm.maxabs16 = .00005;/* 1/20000 */
-   pm.maxcalc16 =1./65535;/* +/-1 in 16 bits for compose errors */
-   pm.maxcalcG = 1./((1<<PNG_MAX_GAMMA_8)-1);
+   pm.maxcalc16 =.000015;/* +/-1 in 16 bits for compose errors */
 
    /* NOTE: this is a reasonable perceptual limit. We assume that humans can
     * perceive light level differences of 1% over a 100:1 range, so we need to
@@ -10097,16 +9892,13 @@ int main(int argc, char **argv)
          pm.interlace_type = PNG_INTERLACE_ADAM7;
 
       else if (strcmp(*argv, "--use-input-precision") == 0)
-         pm.use_input_precision = 1U;
-
-      else if (strcmp(*argv, "--use-calculation-precision") == 0)
-         pm.use_input_precision = 0;
+         pm.use_input_precision = 1;
 
       else if (strcmp(*argv, "--calculations-use-input-precision") == 0)
-         pm.calculations_use_input_precision = 1U;
+         pm.calculations_use_input_precision = 1;
 
       else if (strcmp(*argv, "--assume-16-bit-calculations") == 0)
-         pm.assume_16_bit_calculations = 1U;
+         pm.assume_16_bit_calculations = 1;
 
       else if (strcmp(*argv, "--calculations-follow-bit-depth") == 0)
          pm.calculations_use_input_precision =
@@ -10347,6 +10139,7 @@ int main(int argc, char **argv)
 int main(void)
 {
    fprintf(stderr, "pngvalid: no write support in libpng, all tests skipped\n");
-   return 0;
+   /* So the test is skipped: */
+   return 77;
 }
 #endif

contrib/libtests/readpng.c

@@ -2,7 +2,7 @@
  *
  * Copyright (c) 2013 John Cunningham Bowler
  *
- * Last changed in libpng 1.6.0 [(PENDING RELEASE)]
+ * Last changed in libpng 1.6.1 [March 28, 2013]
  *
  * This code is released under the libpng license.
  * For conditions of distribution and use, see the disclaimer
@@ -18,7 +18,7 @@
 #include <stdio.h>
 #include <string.h>
 
-#if (defined HAVE_CONFIG_H) && !(defined PNG_NO_CONFIG_H)
+#if defined(HAVE_CONFIG_H) && !defined(PNG_NO_CONFIG_H)
 #  include <config.h>
 #endif
 

contrib/libtests/tarith.c

@@ -1,9 +1,9 @@
 
 /* tarith.c
  *
- * Copyright (c) 2011,2012 John Cunningham Bowler
+ * Copyright (c) 2011-2013 John Cunningham Bowler
  *
- * Last changed in libpng 1.6.0 [(PENDING RELEASE)]
+ * Last changed in libpng 1.6.0 [February 14, 2013]
  *
  * This code is released under the libpng license.
  * For conditions of distribution and use, see the disclaimer

contrib/libtests/test-pngstest.sh

@@ -1,24 +0,0 @@
-#!/bin/sh
-#
-# Run the simplified API tests
-err=0
-
-echo >> pngtest-log.txt
-echo "============ pngstest.sh ==============" >> pngtest-log.txt
-
-echo "Running test-pngstest.sh"
-for image in ${srcdir}/contrib/pngsuite/*.png
-do
-   for opts in ""
-   do
-      if ./pngstest --strict --log "$@" $opts $image >>pngtest-log.txt 2>&1
-      then
-         echo "  PASS: pngstest $opts $image"
-      else
-         echo "  FAIL: pngstest $opts $image"
-         err=1
-      fi
-   done
-done
-
-exit $err

contrib/libtests/test-pngunknown.sh

@@ -1,38 +0,0 @@
-#!/bin/sh
-#
-# Run the unknown API tests
-err=0
-image="${srcdir}/pngtest.png"
-#
-# stream 4 is used for the output of the shell, pngtest-log.txt gets all the
-# normal program output.
-exec 4>&1 1>>pngtest-log.txt 2>&1
-
-echo
-echo "============ test-pngunknown.sh =============="
-
-echo "Running test-pngunknown.sh" >&4
-
-for tests in \
- "discard default=discard"\
- "save default=save"\
- "if-safe default=if-safe"\
- "vpAg vpAg=if-safe"\
- "sTER sTER=if-safe"\
- "IDAT default=discard IDAT=save"\
- "sAPI bKGD=save cHRM=save gAMA=save all=discard iCCP=save sBIT=save sRGB=save"
-do
-   set $tests
-   test="$1"
-   shift
-
-   if ./pngunknown "$@" "$image" 4>&-
-   then
-      echo "  PASS: test-pngunknown $test" >&4
-   else
-      echo "  FAIL: test-pngunknown $test" >&4
-      err=1
-   fi
-done
-
-exit $err

contrib/libtests/test-pngvalid-full.sh

@@ -1,21 +0,0 @@
-#!/bin/sh
-#
-# Run a sequence of gamma tests quietly
-err=0
-
-echo >> pngtest-log.txt
-echo "============ pngvalid-full.sh ==============" >> pngtest-log.txt
-
-echo "Running test-pngvalid-full.sh"
-for gamma in threshold transform sbit 16-to-8 background alpha-mode "transform --expand16" "background --expand16" "alpha-mode --expand16"
-do
-   if ./pngvalid "$@" --gamma-$gamma >> pngtest-log.txt 2>&1
-   then
-      echo "  PASS: pngvalid" "$@" "--gamma-$gamma"
-   else
-      echo "  FAIL: pngvalid" "$@" "--gamma-$gamma"
-      err=1
-   fi
-done
-
-exit $err

contrib/libtests/test-pngvalid-simple.sh

@@ -1,30 +0,0 @@
-#!/bin/sh
-#
-# Run a sequence of tests quietly, without the slow
-# gamma tests
-err=0
-
-echo >> pngtest-log.txt
-echo "============ pngvalid-simple.sh ==============" >> pngtest-log.txt
-echo "Running test-pngvalid-simple.sh"
-# The options to test are:
-#
-# standard tests with and without progressive reading and interlace
-# size images with and without progressive reading
-# transform tests (standard, non-interlaced only)
-#
-for opts in "--standard" "--standard --progressive-read" \
-   "--standard --interlace" "--standard --progressive-read --interlace" \
-   "--size" "--size --progressive-read" \
-   "--transform"
-do
-   if ./pngvalid "$@" $opts >> pngtest-log.txt 2>&1
-   then
-      echo "  PASS: pngvalid" "$@" $opts
-   else
-      echo "  FAIL: pngvalid" "$@" $opts
-      err=1
-   fi
-done
-
-exit $err

contrib/libtests/timepng.c

@@ -1,8 +1,8 @@
 /* timepng.c
  *
- * Copyright (c) 2012 John Cunningham Bowler
+ * Copyright (c) 2013 John Cunningham Bowler
  *
- * Last changed in libpng 1.6.0 [(PENDING RELEASE)]
+ * Last changed in libpng 1.6.1 [March 28, 2013]
  *
  * This code is released under the libpng license.
  * For conditions of distribution and use, see the disclaimer
@@ -22,7 +22,7 @@
 
 #include <time.h>
 
-#if (defined HAVE_CONFIG_H) && !(defined PNG_NO_CONFIG_H)
+#if defined(HAVE_CONFIG_H) && !defined(PNG_NO_CONFIG_H)
 #  include <config.h>
 #endif
 

contrib/pngminim/decoder/makefile

@@ -14,7 +14,8 @@ LD=$(CC)
 RM=rm -f
 COPY=cp
 
-CFLAGS=-DPNG_USER_CONFIG -DNO_GZCOMPRESS -DZ_SOLO -DNO_GZIP -I. -O1
+CPPFLAGS=-I. -DPNG_USER_CONFIG -DNO_GZCOMPRESS -DZ_SOLO -DNO_GZIP
+CFLAGS=-O1
 
 C=.c
 O=.o
@@ -81,7 +82,7 @@ OBJS    = $(PROGOBJS) $(PNGOBJS) $(ZOBJS)
 
 # note: dependencies do not work on implicit rule lines
 .c$(O):
-	$(CC) -c $(CFLAGS) $<
+	$(CC) $(CPPFLAGS) -c $(CFLAGS) $<
 
 # dependencies
 
@@ -95,12 +96,12 @@ pngm2pnm$(E): $(OBJS)
 # The CPP_FLAGS setting causes pngusr.h to be included in
 # both the build of pnglibconf.h and, subsequently, when
 # building libpng itself.
-$(PNGCONF): $(PNGSRC)/scripts/pnglibconf.mak\
+$(PNGCONF): $(PNGSRC)/scripts/pnglibconf.mak $(ZH)\
 	$(PNGSRC)/scripts/pnglibconf.dfa \
 	$(PNGSRC)/scripts/options.awk pngusr.h pngusr.dfa
 	$(RM) pnglibconf.h pnglibconf.dfn
 	$(MAKE) $(MAKEFLAGS) -f $(PNGSRC)/scripts/pnglibconf.mak\
-	    srcdir=$(PNGSRC) CPPFLAGS="-DPNG_USER_CONFIG"\
+	    srcdir=$(PNGSRC) CPPFLAGS="-DPNG_USER_CONFIG -I."\
 	    DFA_XTRA="pngusr.dfa" $@
 
 clean:

contrib/pngminim/decoder/pngusr.dfa

@@ -1,6 +1,6 @@
 # pngminim/decoder/pngusr.dfa
 #
-# Copyright (c) 2010-2011 Glenn Randers-Pehrson
+# Copyright (c) 2010-2013 Glenn Randers-Pehrson
 #
 # This code is released under the libpng license.
 # For conditions of distribution and use, see the disclaimer

contrib/pngminim/decoder/pngusr.h

@@ -1,6 +1,6 @@
 /* minrdpngconf.h: headers to make a minimal png-read-only library
  *
- * Copyright (c) 2007, 2010-2011 Glenn Randers-Pehrson
+ * Copyright (c) 2007, 2010-2013 Glenn Randers-Pehrson
  *
  * This code is released under the libpng license.
  * For conditions of distribution and use, see the disclaimer

contrib/pngminim/encoder/makefile

@@ -14,7 +14,8 @@ LD=$(CC)
 RM=rm -f
 COPY=cp
 
-CFLAGS=-DPNG_USER_CONFIG -DZ_SOLO -DNO_GZIP -I. -O1
+CPPFLAGS=-I. -DPNG_USER_CONFIG -DNO_GZCOMPRESS -DZ_SOLO -DNO_GZIP
+CFLAGS=-O1
 
 C=.c
 O=.o
@@ -80,7 +81,7 @@ OBJS    = $(PROGOBJS) $(PNGOBJS) $(ZOBJS)
 # implicit make rules -------------------------------------------------------
 
 .c$(O):
-	$(CC) -c $(CFLAGS) $<
+	$(CC) $(CPPFLAGS) -c $(CFLAGS) $<
 
 # dependencies
 
@@ -94,12 +95,12 @@ pnm2pngm$(E): $(OBJS)
 # The CPP_FLAGS setting causes pngusr.h to be included in
 # both the build of pnglibconf.h and, subsequently, when
 # building libpng itself.
-$(PNGCONF): $(PNGSRC)/scripts/pnglibconf.mak\
+$(PNGCONF): $(PNGSRC)/scripts/pnglibconf.mak $(ZH)\
 	$(PNGSRC)/scripts/pnglibconf.dfa \
 	$(PNGSRC)/scripts/options.awk pngusr.h pngusr.dfa
 	$(RM) pnglibconf.h pnglibconf.dfn
 	$(MAKE) $(MAKEFLAGS) -f $(PNGSRC)/scripts/pnglibconf.mak\
-	    srcdir=$(PNGSRC) CPPFLAGS="-DPNG_USER_CONFIG"\
+	    srcdir=$(PNGSRC) CPPFLAGS="-DPNG_USER_CONFIG -I."\
 	    DFA_XTRA="pngusr.dfa" $@
 
 clean:

contrib/pngminim/encoder/pngusr.dfa

@@ -1,6 +1,6 @@
 # pngminim/encoder/pngusr.dfa
 #
-# Copyright (c) 2010-2011 Glenn Randers-Pehrson
+# Copyright (c) 2010-2013 Glenn Randers-Pehrson
 #
 # This code is released under the libpng license.
 # For conditions of distribution and use, see the disclaimer
@@ -13,6 +13,9 @@ everything = off
 # Switch on the write code - this makes a minimalist encoder
 
 option WRITE on
+# These 2 options are required if you need to read PGM (P1 or P4) PGM files.
+# option WRITE_INVERT on
+# option WRITE_PACK on
 
 # You must choose fixed or floating point arithmetic:
 # option FLOATING_POINT on

contrib/pngminim/encoder/pngusr.h

@@ -1,6 +1,6 @@
 /* minwrpngconf.h: headers to make a minimal png-write-only library
  *
- * Copyright (c) 2007, 2010-2011 Glenn Randers-Pehrson
+ * Copyright (c) 2007, 2010-2013 Glenn Randers-Pehrson
  *
  * This code is released under the libpng license.
  * For conditions of distribution and use, see the disclaimer

contrib/pngminim/preader/makefile

@@ -30,7 +30,8 @@ XLIB = -L/usr/X11R6/lib -lX11
 #LIBS = $(XLIB)
 LIBS = $(XLIB) -lm                      #platforms that need libm
 
-CFLAGS=-DPNG_USER_CONFIG -DNO_GZCOMPRESS -DZ_SOLO -DNO_GZIP -I. $(XINC) -O1
+CPPFLAGS=-I. $(XINC) -DPNG_USER_CONFIG -DNO_GZCOMPRESS -DZ_SOLO -DNO_GZIP
+CFLAGS=-O1
 
 C=.c
 O=.o
@@ -96,7 +97,7 @@ OBJS    = $(PROGOBJS) $(PNGOBJS) $(ZOBJS)
 # implicit make rules -------------------------------------------------------
 
 .c$(O):
-	$(CC) -c $(CFLAGS) $<
+	$(CC) $(CPPFLAGS) -c $(CFLAGS) $<
 
 # dependencies
 
@@ -110,12 +111,12 @@ rpng2-x$(E): $(OBJS)
 # The CPP_FLAGS setting causes pngusr.h to be included in
 # both the build of pnglibconf.h and, subsequently, when
 # building libpng itself.
-$(PNGCONF): $(PNGSRC)/scripts/pnglibconf.mak\
+$(PNGCONF): $(PNGSRC)/scripts/pnglibconf.mak $(ZH)\
 	$(PNGSRC)/scripts/pnglibconf.dfa \
 	$(PNGSRC)/scripts/options.awk pngusr.h pngusr.dfa
 	$(RM) pnglibconf.h pnglibconf.dfn
 	$(MAKE) $(MAKEFLAGS) -f $(PNGSRC)/scripts/pnglibconf.mak\
-	    srcdir=$(PNGSRC) CPPFLAGS="-DPNG_USER_CONFIG"\
+	    srcdir=$(PNGSRC) CPPFLAGS="-DPNG_USER_CONFIG -I."\
 	    DFA_XTRA="pngusr.dfa" $@
 
 clean:

contrib/pngminim/preader/pngusr.dfa

@@ -1,6 +1,6 @@
 # pngminim/preader/pngusr.dfa
 #
-# Copyright (c) 2010-2011 Glenn Randers-Pehrson
+# Copyright (c) 2010-2013 Glenn Randers-Pehrson
 #
 # This code is released under the libpng license.
 # For conditions of distribution and use, see the disclaimer

contrib/pngminim/preader/pngusr.h

@@ -1,6 +1,6 @@
 /* minrdpngconf.h: headers to make a minimal png-read-only library
  *
- * Copyright (c) 2009, 2010-2011 Glenn Randers-Pehrson
+ * Copyright (c) 2009, 2010-2013 Glenn Randers-Pehrson
  *
  * This code is released under the libpng license.
  * For conditions of distribution and use, see the disclaimer

contrib/pngminus/makefile.std

@@ -8,9 +8,9 @@ LD=$(CC)
 RM=rm -f
 
 #PNGPATH = /usr/local
-#PNGINC = -I$(PNGPATH)/include/libpng17
-#PNGLIB = -L$(PNGPATH)/lib -lpng17
-#PNGLIBS = $(PNGPATH)/lib/libpng17.a
+#PNGINC = -I$(PNGPATH)/include/libpng16
+#PNGLIB = -L$(PNGPATH)/lib -lpng16
+#PNGLIBS = $(PNGPATH)/lib/libpng16.a
 PNGINC = -I../..
 PNGLIB = -L../.. -lpng
 PNGLIBS = ../../libpng.a

contrib/pngminus/pnm2png.c

@@ -198,9 +198,9 @@ BOOL pnm2png (FILE *pnm_file, FILE *png_file, FILE *alpha_file, BOOL interlace,
   char          height_token[16];
   char          maxval_token[16];
   int           color_type;
-  unsigned long   ul_width, ul_alpha_width;
-  unsigned long   ul_height, ul_alpha_height;
-  unsigned long   ul_maxval;
+  unsigned long   ul_width=0, ul_alpha_width=0;
+  unsigned long   ul_height=0, ul_alpha_height=0;
+  unsigned long   ul_maxval=0;
   png_uint_32   width, alpha_width;
   png_uint_32   height, alpha_height;
   png_uint_32   maxval;
@@ -210,6 +210,9 @@ BOOL pnm2png (FILE *pnm_file, FILE *png_file, FILE *alpha_file, BOOL interlace,
   int           alpha_present;
   int           row, col;
   BOOL          raw, alpha_raw = FALSE;
+#if defined(PNG_WRITE_INVERT_SUPPORTED) || defined(PNG_WRITE_PACK_SUPPORTED)
+  BOOL          packed_bitmap = FALSE;
+#endif
   png_uint_32   tmp16;
   int           i;
 
@@ -222,9 +225,21 @@ BOOL pnm2png (FILE *pnm_file, FILE *png_file, FILE *alpha_file, BOOL interlace,
   }
   else if ((type_token[1] == '1') || (type_token[1] == '4'))
   {
+#if defined(PNG_WRITE_INVERT_SUPPORTED) || defined(PNG_WRITE_PACK_SUPPORTED)
     raw = (type_token[1] == '4');
     color_type = PNG_COLOR_TYPE_GRAY;
+    get_token(pnm_file, width_token);
+    sscanf (width_token, "%lu", &ul_width);
+    width = (png_uint_32) ul_width;
+    get_token(pnm_file, height_token);
+    sscanf (height_token, "%lu", &ul_height);
+    height = (png_uint_32) ul_height;
     bit_depth = 1;
+    packed_bitmap = TRUE;
+#else
+    fprintf (stderr, "PNM2PNG built without PNG_WRITE_INVERT_SUPPORTED and \n");
+    fprintf (stderr, "PNG_WRITE_PACK_SUPPORTED can't read PBM (P1,P4) files\n");
+#endif
   }
   else if ((type_token[1] == '2') || (type_token[1] == '5'))
   {
@@ -343,8 +358,14 @@ BOOL pnm2png (FILE *pnm_file, FILE *png_file, FILE *alpha_file, BOOL interlace,
 
   alpha_present = (channels - 1) % 2;
 
-  /* row_bytes is the width x number of channels x (bit-depth / 8) */
-  row_bytes = width * channels * ((bit_depth <= 8) ? 1 : 2);
+#if defined(PNG_WRITE_INVERT_SUPPORTED) || defined(PNG_WRITE_PACK_SUPPORTED)
+  if (packed_bitmap)
+    /* row data is as many bytes as can fit width x channels x bit_depth */
+    row_bytes = (width * channels * bit_depth + 7) / 8;
+  else
+#endif
+    /* row_bytes is the width x number of channels x (bit-depth / 8) */
+    row_bytes = width * channels * ((bit_depth <= 8) ? 1 : 2);
 
   if ((png_pixels = (png_byte *) malloc (row_bytes * height * sizeof (png_byte))) == NULL)
     return FALSE;
@@ -354,40 +375,48 @@ BOOL pnm2png (FILE *pnm_file, FILE *png_file, FILE *alpha_file, BOOL interlace,
 
   for (row = 0; row < height; row++)
   {
-    for (col = 0; col < width; col++)
+#if defined(PNG_WRITE_INVERT_SUPPORTED) || defined(PNG_WRITE_PACK_SUPPORTED)
+    if (packed_bitmap) {
+      for (i = 0; i < row_bytes; i++)
+        /* png supports this format natively so no conversion is needed */
+        *pix_ptr++ = get_data (pnm_file, 8);
+    } else
+#endif
     {
-      for (i = 0; i < (channels - alpha_present); i++)
+      for (col = 0; col < width; col++)
       {
-        if (raw)
-          *pix_ptr++ = get_data (pnm_file, bit_depth);
-        else
-          if (bit_depth <= 8)
-            *pix_ptr++ = get_value (pnm_file, bit_depth);
+        for (i = 0; i < (channels - alpha_present); i++)
+        {
+          if (raw)
+            *pix_ptr++ = get_data (pnm_file, bit_depth);
           else
-          {
-            tmp16 = get_value (pnm_file, bit_depth);
-            *pix_ptr = (png_byte) ((tmp16 >> 8) & 0xFF);
-            pix_ptr++;
-            *pix_ptr = (png_byte) (tmp16 & 0xFF);
-            pix_ptr++;
-          }
-      }
+            if (bit_depth <= 8)
+              *pix_ptr++ = get_value (pnm_file, bit_depth);
+            else
+            {
+              tmp16 = get_value (pnm_file, bit_depth);
+              *pix_ptr = (png_byte) ((tmp16 >> 8) & 0xFF);
+              pix_ptr++;
+              *pix_ptr = (png_byte) (tmp16 & 0xFF);
+              pix_ptr++;
+            }
+        }
 
-      if (alpha) /* read alpha-channel from pgm file */
-      {
-        if (alpha_raw)
-          *pix_ptr++ = get_data (alpha_file, alpha_depth);
-        else
-          if (alpha_depth <= 8)
-            *pix_ptr++ = get_value (alpha_file, bit_depth);
+        if (alpha) /* read alpha-channel from pgm file */
+        {
+          if (alpha_raw)
+            *pix_ptr++ = get_data (alpha_file, alpha_depth);
           else
-          {
-            tmp16 = get_value (alpha_file, bit_depth);
-            *pix_ptr++ = (png_byte) ((tmp16 >> 8) & 0xFF);
-            *pix_ptr++ = (png_byte) (tmp16 & 0xFF);
-          }
-      } /* if alpha */
-
+            if (alpha_depth <= 8)
+              *pix_ptr++ = get_value (alpha_file, bit_depth);
+            else
+            {
+              tmp16 = get_value (alpha_file, bit_depth);
+              *pix_ptr++ = (png_byte) ((tmp16 >> 8) & 0xFF);
+              *pix_ptr++ = (png_byte) (tmp16 & 0xFF);
+            }
+        } /* if alpha */
+      } /* if packed_bitmap */
     } /* end for col */
   } /* end for row */
 
@@ -404,6 +433,14 @@ BOOL pnm2png (FILE *pnm_file, FILE *png_file, FILE *alpha_file, BOOL interlace,
     return FALSE;
   }
 
+#if defined(PNG_WRITE_INVERT_SUPPORTED) || defined(PNG_WRITE_PACK_SUPPORTED)
+  if (packed_bitmap == TRUE)
+  {
+    png_set_packing (png_ptr);
+    png_set_invert_mono (png_ptr);
+  }
+#endif
+
   /* setjmp() must be called in every function that calls a PNG-reading libpng function */
   if (setjmp (png_jmpbuf(png_ptr)))
   {
@@ -460,19 +497,32 @@ BOOL pnm2png (FILE *pnm_file, FILE *png_file, FILE *alpha_file, BOOL interlace,
 void get_token(FILE *pnm_file, char *token)
 {
   int i = 0;
+  int ret;
 
-  /* remove white-space */
+  /* remove white-space and comment lines */
   do
   {
-    token[i] = (unsigned char) fgetc (pnm_file);
+    ret = fgetc(pnm_file);
+    if (ret == '#') {
+      /* the rest of this line is a comment */
+      do
+      {
+        ret = fgetc(pnm_file);
+      }
+      while ((ret != '\n') && (ret != '\r') && (ret != EOF));
+    }
+    if (ret == EOF) break;
+    token[i] = (unsigned char) ret;
   }
   while ((token[i] == '\n') || (token[i] == '\r') || (token[i] == ' '));
 
   /* read string */
   do
   {
+    ret = fgetc(pnm_file);
+    if (ret == EOF) break;
     i++;
-    token[i] = (unsigned char) fgetc (pnm_file);
+    token[i] = (unsigned char) ret;
   }
   while ((token[i] != '\n') && (token[i] != '\r') && (token[i] != ' '));
 

contrib/tools/checksum-icc.c

@@ -1,8 +1,8 @@
 /* checksum-icc.c
  *
- * Copyright (c) 2012 John Cunningham Bowler
+ * Copyright (c) 2013 John Cunningham Bowler
  *
- * Last changed in libpng 1.6.0 [(PENDING RELEASE)]
+ * Last changed in libpng 1.6.0 [February 14, 2013]
  *
  * This code is released under the libpng license.
  * For conditions of distribution and use, see the disclaimer

contrib/tools/cvtcolor.c

@@ -1,9 +1,9 @@
 /*-
  * convert.c
  *
- * Last changed in libpng 1.6.0 [(PENDING RELEASE)]
+ * Last changed in libpng 1.6.0 [February 14, 2013]
  *
- * COPYRIGHT: Written by John Cunningham Bowler, 2012.
+ * COPYRIGHT: Written by John Cunningham Bowler, 2013.
  * To the extent possible under law, the author has waived all copyright and
  * related or neighboring rights to this work.  This work is published from:
  * United States.

contrib/tools/intgamma.sh

@@ -2,9 +2,9 @@
 #
 # intgamma.sh
 #
-# Last changed in libpng 1.6.0 [(PENDING RELEASE)]
+# Last changed in libpng 1.6.0 [February 14, 2013]
 #
-# COPYRIGHT: Written by John Cunningham Bowler, 2012.
+# COPYRIGHT: Written by John Cunningham Bowler, 2013.
 # To the extent possible under law, the author has waived all copyright and
 # related or neighboring rights to this work.  This work is published from:
 # United States.

contrib/tools/makesRGB.c

@@ -1,8 +1,8 @@
 /* makesRGB.c -- build sRGB-to-linear and linear-to-sRGB conversion tables
  *
- * Last changed in libpng 1.6.0 [(PENDING RELEASE)]
+ * Last changed in libpng 1.6.0 [February 14, 2013]
  *
- * COPYRIGHT: Written by John Cunningham Bowler, 2012.
+ * COPYRIGHT: Written by John Cunningham Bowler, 2013.
  * To the extent possible under law, the author has waived all copyright and
  * related or neighboring rights to this work.  This work is published from:
  * United States.

contrib/tools/png-fix-itxt.c

@@ -0,0 +1,153 @@
+
+/* png-fix-itxt version 1.0.0
+ *
+ * Copyright 2013 Glenn Randers-Pehrson
+ * Last changed in libpng 1.6.3 [(PENDING RELEASE)]
+ *
+ * This code is released under the libpng license.
+ * For conditions of distribution and use, see the disclaimer
+ * and license in png.h
+ *
+ * Usage:            
+ *
+ *     png-fix-itxt.exe < bad.png > good.png
+ *
+ * Fixes a PNG file written with libpng-1.6.0 or 1.6.1 that has one or more
+ * uncompressed iTXt chunks.  Assumes that the actual length is greater
+ * than or equal to the value in the length byte, and that the CRC is
+ * correct for the actual length.  This program hunts for the CRC and
+ * adjusts the length byte accordingly.  It is not an error to process a
+ * PNG file that has no iTXt chunks or one that has valid iTXt chunks;
+ * such files will simply be copied.
+ *
+ * Requires zlib (for crc32 and Z_NULL); build with
+ *
+ *     gcc -O -o png-fix-itxt png-fix-itxt.c -lz
+ *
+ * If you need to handle iTXt chunks larger than 500000 kbytes you must
+ * rebuild png-fix-itxt with a larger values of MAX_LENGTH (or a smaller value
+ * if you know you will never encounter such huge iTXt chunks).
+ */
+
+#include <stdio.h>
+#include <zlib.h>
+
+#define MAX_LENGTH 500000
+
+#define GETBREAK ((unsigned char)(inchar=getchar())); if (inchar == EOF) break
+
+int
+main(void)
+{
+   unsigned int i;
+   unsigned char buf[MAX_LENGTH];
+   unsigned long crc;
+   unsigned char c;
+   int inchar;
+
+/* Skip 8-byte signature */
+   for (i=8; i; i--)
+   {
+      c=GETBREAK;
+      putchar(c);
+   }
+
+if (inchar != EOF)
+for (;;)
+ {
+   /* Read the length */
+   unsigned long length; /* must be 32 bits! */
+   c=GETBREAK; buf[0] = c; length  = c; length <<= 8;
+   c=GETBREAK; buf[1] = c; length += c; length <<= 8;
+   c=GETBREAK; buf[2] = c; length += c; length <<= 8;
+   c=GETBREAK; buf[3] = c; length += c;
+
+   /* Read the chunkname */
+   c=GETBREAK; buf[4] = c;
+   c=GETBREAK; buf[5] = c;
+   c=GETBREAK; buf[6] = c;
+   c=GETBREAK; buf[7] = c;
+
+
+   /* The iTXt chunk type expressed as integers is (105, 84, 88, 116) */
+   if (buf[4] == 105 && buf[5] == 84 && buf[6] == 88 && buf[7] == 116)
+   {
+      if (length >= MAX_LENGTH-12)
+         break;  /* To do: handle this more gracefully */
+
+      /* Initialize the CRC */
+      crc = crc32(0, Z_NULL, 0);
+
+      /* Copy the data bytes */
+      for (i=8; i < length + 12; i++)
+      {
+         c=GETBREAK; buf[i] = c;
+      }
+
+      /* Calculate the CRC */
+      crc = crc32(crc, buf+4, (uInt)length+4);
+
+      for (;;)
+      {
+        /* Check the CRC */
+        if (((crc >> 24) & 0xff) == buf[length+8] &&
+            ((crc >> 16) & 0xff) == buf[length+9] &&
+            ((crc >>  8) & 0xff) == buf[length+10] &&
+            ((crc      ) & 0xff) == buf[length+11])
+           break;
+
+        length++;
+
+        if (length >= MAX_LENGTH-12)
+           break;
+
+        c=GETBREAK;
+        buf[length+11]=c;
+
+        /* Update the CRC */
+        crc = crc32(crc, buf+7+length, 1);
+      }
+
+      /* Update length bytes */
+        buf[0] = (length << 24) & 0xff;
+        buf[1] = (length << 16) & 0xff;
+        buf[2] = (length <<  8) & 0xff;
+        buf[3] = (length      ) & 0xff;
+
+      /* Write the fixed iTXt chunk (length, name, data, crc) */
+      for (i=0; i<length+12; i++)
+         putchar(buf[i]);
+   }
+
+   else
+   {
+      /* Copy bytes that were already read (length and chunk name) */
+      for (i=0; i<8; i++)
+         putchar(buf[i]);
+
+      /* Copy data bytes and CRC */
+      for (i=8; i< length+12; i++)
+      {
+         c=GETBREAK;
+         putchar(c);
+      }
+
+      if (inchar == EOF)
+      {
+         break;
+      }
+
+   /* The IEND chunk type expressed as integers is (73, 69, 78, 68) */
+      if (buf[4] == 73 && buf[5] == 69 && buf[6] == 78 && buf[7] == 68)
+         break;
+   }
+
+   if (inchar == EOF)
+      break;
+
+   if (buf[4] == 73 && buf[5] == 69 && buf[6] == 78 && buf[7] == 68)
+     break;
+ }
+
+ return 0;
+}

contrib/tools/sRGB.h

@@ -1,9 +1,9 @@
 /*-
  * sRGB.h
  *
- * Last changed in libpng 1.6.0 [(PENDING RELEASE)]
+ * Last changed in libpng 1.6.0 [February 14, 2013]
  *
- * COPYRIGHT: Written by John Cunningham Bowler, 2012.
+ * COPYRIGHT: Written by John Cunningham Bowler, 2013.
  * To the extent possible under law, the author has waived all copyright and
  * related or neighboring rights to this work.  This work is published from:
  * United States.

contrib/tools/scale.c

@@ -1,238 +0,0 @@
-/* Given a target range and a source range work out an expression to scale from
- * the source to the target of the form:
- *
- *    (number * mult + add)>>16
- *
- * The command arguments are:
- *
- *    scale target source
- *
- * and the program works out a pair of numbers, mult and add, that evaluate:
- *
- *          number * target
- *   round( --------------- )
- *              source
- *
- * exactly for number in the range 0..source
- */
-#define _ISOC99_SOURCE 1
-
-#include <stdlib.h>
-#include <string.h>
-#include <stdio.h>
-#include <math.h>
-
-static double minerr;
-static unsigned long minmult, minadd, minshift;
-static long mindelta;
-
-static int
-test(unsigned long target, unsigned long source, unsigned long mult,
-   long add, unsigned long shift, long delta)
-{
-   unsigned long i;
-   double maxerr = 0;
-   double rs = (double)target/source;
-
-   for (i=0; i<=source; ++i)
-   {
-      unsigned long t = i*mult+add;
-      double err = fabs((t >> shift) - i*rs);
-
-      if (err > minerr)
-         return 0;
-
-      if (err > maxerr)
-         maxerr = err;
-   }
-
-   if (maxerr < minerr)
-   {
-      minerr = maxerr;
-      minmult = mult;
-      minadd = add;
-      minshift = shift;
-      mindelta = delta;
-   }
-
-   return maxerr < .5;
-}
-
-static int
-dotest(unsigned long target, unsigned long source, unsigned long mult,
-   long add, unsigned long shift, long delta, int print)
-{
-   if (test(target, source, mult, add, shift, delta))
-   {
-      if (print & 4)
-         printf("      {%11lu,%6ld /* >>%lu */ }, /* %lu/%lu */\n",
-            mult, add, shift, target, source);
-
-      else if (print & 2)
-         printf("      {%11lu,%6ld,%3lu }, /* %lu/%lu */\n",
-            mult, add, shift, target, source);
-
-      else if (print)
-         printf("number * %lu/%lu = (number * %lu + %ld) >> %lu [delta %ld]\n",
-            target, source, mult, add, shift, delta);
-
-      return 1;
-   }
-
-   return 0;
-}
-
-static int
-find(unsigned long target, unsigned long source, int print, int fixshift)
-{
-   unsigned long shift = 0;
-   unsigned long shiftlim = 0;
-
-   /* In the final math the sum is at most (source*mult+add) >> shift, so:
-    *
-    *    source*mult+add < 1<<32
-    *    mult < (1<<32)/source
-    *
-    * but:
-    *
-    *    mult = (target<<shift)/source
-    *
-    * so:
-    *
-    *    (target<<shift) < (1<<32)
-    */
-   if (fixshift < 0)
-      while ((target<<shiftlim) < 0x80000000U) ++shiftlim;
-
-   else
-      shift = shiftlim = (unsigned long)fixshift;
-
-   minerr = 1E8;
-
-   for (; shift<=shiftlim; ++shift)
-   {
-      unsigned long mult = ((target<<shift) + (source>>1)) / source;
-      long delta;
-      long limit = 1; /* seems to be sufficient */
-      long add, start, end;
-
-      end = 1<<shift;
-      start = -end;
-
-      for (add=start; add<=end; ++add)
-         if (dotest(target,source,mult,add,shift,0,print))
-            return 1;
-
-      for (delta=1; delta<=limit; ++delta)
-      {
-#        if 0
-            fprintf(stderr, "%lu/%lu: shift %lu, delta %lu\n", target, source,
-               shift, delta);
-#        endif
-
-         for (add=start; add<=end; ++add)
-         {
-            if (dotest(target, source, mult-delta, add, shift, -delta, print))
-               return 1;
-
-            if (dotest(target, source, mult+delta, add, shift, delta, print))
-               return 1;
-         }
-      }
-   }
-
-   if (print & 4)
-      printf("      {%11lu,%6ld /* >>%lu */ }, /* %lu/%lu ERROR: .5+%g*/\n",
-         minmult, minadd, minshift, target, source, minerr-.5);
-
-   else if (print & 2)
-      printf("      {%11lu,%6ld,%3lu }, /* %lu/%lu ERROR: .5+%g*/\n",
-         minmult, minadd, minshift, target, source, minerr-.5);
-
-   else if (print)
-      printf(
-         "number * %lu/%lu ~= (number * %lu + %ld) >> %lu +/-.5+%g [delta %ld]\n",
-         target, source, minmult, minadd, minshift, minerr-.5, mindelta);
-
-   return 0;
-}
-
-static void
-usage(const char *prog)
-{
-   fprintf(stderr,
-      "usage: %s {--denominator|--maxshift|--code} target {source}\n"
-      " For each 'source' prints 'mult' and 'add' such that:\n\n"
-      "   (number * mult + add) >> 16 = round(number*target/source)\n\n"
-      " for all integer values of number in the range 0..source.\n\n"
-      " --denominator: swap target and source (specify a single source first\n"
-      "                and follow with multiple targets.)\n"
-      "    --maxshift: find the lowest shift value that works for all the\n"
-      "                repeated 'source' values\n"
-      "        --code: output C code for array/structure initialization\n",
-      prog);
-   exit(1);
-}
-
-int
-main(int argc, const char **argv)
-{
-   int i, err = 0, maxshift = 0, firstsrc = 1, code = 0, denominator = 0;
-   unsigned long target, shift = 0;
-
-   while (argc > 1)
-   {
-      if (strcmp(argv[firstsrc], "--maxshift") == 0)
-      {
-         maxshift = 1;
-         ++firstsrc;
-      }
-
-      else if (strcmp(argv[firstsrc], "--code") == 0)
-      {
-         code = 1;
-         ++firstsrc;
-      }
-
-      else if (strcmp(argv[firstsrc], "--denominator") == 0)
-      {
-         denominator = 1;
-         ++firstsrc;
-      }
-
-      else
-         break;
-   }
-
-
-   if (argc < 2+firstsrc)
-      usage(argv[0]);
-
-   target = strtoul(argv[firstsrc++], 0, 0);
-   if (target == 0) usage(argv[0]);
-
-   for (i=firstsrc; i<argc; ++i)
-   {
-      unsigned long source = strtoul(argv[i], 0, 0);
-
-      if (source == 0) usage(argv[0]);
-
-      if (!find(denominator ? source : target, denominator ? target : source,
-         maxshift ? 0 : 1+code, -1))
-         err = 1;
-
-      if (minshift > shift) shift = minshift;
-   }
-
-   if (maxshift) for (i=firstsrc; i<argc; ++i)
-   {
-      unsigned long source = strtoul(argv[i], 0, 0);
-
-      if (!find(denominator ? source : target, denominator ? target : source,
-         code ? 4 : 1, shift))
-         err = 1;
-   }
-
-   /* Just an exit code - the printout above lists the problem */
-   return err;
-}

example.c

@@ -2,7 +2,7 @@
 #if 0 /* in case someone actually tries to compile this */
 
 /* example.c - an example of using libpng
- * Last changed in libpng 1.6.0 [(PENDING RELEASE)]
+ * Last changed in libpng 1.6.0 [February 14, 2013]
  * Maintained 1998-2013 Glenn Randers-Pehrson
  * Maintained 1996, 1997 Andreas Dilger)
  * Written 1995, 1996 Guy Eric Schalnat, Group 42, Inc.)
@@ -39,7 +39,7 @@
 #include <string.h>
 #include <stdio.h>
 #include <png.h>
-#include PNG_ZLIB_HEADER /* this is the header libpng was built with */
+#include <zlib.h>
 
 int main(int argc, const char **argv)
 {

libpng-manual.txt

@@ -1,6 +1,6 @@
 libpng-manual.txt - A description on how to use and modify libpng
 
- libpng version 1.7.0alpha09 - January 21, 2013
+ libpng version 1.6.3beta06 - May 12, 2013
  Updated and distributed by Glenn Randers-Pehrson
  <glennrp at users.sourceforge.net>
  Copyright (c) 1998-2013 Glenn Randers-Pehrson
@@ -11,9 +11,9 @@ libpng-manual.txt - A description on how to use and modify libpng
 
  Based on:
 
- libpng versions 0.97, January 1998, through 1.7.0alpha09 - January 21, 2013
+ libpng versions 0.97, January 1998, through 1.6.3beta06 - May 12, 2013
  Updated and distributed by Glenn Randers-Pehrson
- Copyright (c) 1998-2011 Glenn Randers-Pehrson
+ Copyright (c) 1998-2013 Glenn Randers-Pehrson
 
  libpng 1.0 beta 6  version 0.96 May 28, 1997
  Updated and distributed by Andreas Dilger
@@ -42,18 +42,15 @@ libpng-manual.txt - A description on how to use and modify libpng
     X. Changes to Libpng from version 1.0.x/1.2.x to 1.4.x
    XI. Changes to Libpng from version 1.4.x to 1.5.x
   XII. Changes to Libpng from version 1.5.x to 1.6.x
- XIII. Changes to Libpng from version 1.6.x to 1.7.x
-  XIV. Detecting libpng
-   XV. Source code repository
-  XVI. Coding style
- XVII. Y2K Compliance in libpng
+ XIII. Detecting libpng
+  XIV. Source code repository
+   XV. Coding style
+  XVI. Y2K Compliance in libpng
 
 I. Introduction
 
 This file describes how to use and modify the PNG reference library
-(known as libpng) for your own use.  There are five sections to this
-file: introduction, structures, reading, writing, and modification and
-configuration notes for various special platforms.  In addition to this
+(known as libpng) for your own use.  In addition to this
 file, example.c is a good starting point for using the library, as
 it is heavily commented and should include everything most people
 will need.  We assume that libpng is already installed; see the
@@ -432,7 +429,7 @@ If you would rather avoid the complexity of setjmp/longjmp issues,
 you can compile libpng with PNG_NO_SETJMP, in which case
 errors will result in a call to PNG_ABORT() which defaults to abort().
 
-You can #define PNG_ABORT to a function or other C code that does something
+You can #define PNG_ABORT() to a function that does something
 more useful than abort(), as long as your function does not
 return.
 
@@ -528,9 +525,14 @@ you can retrieve with
     png_get_user_chunk_ptr(png_ptr);
 
 If you call the png_set_read_user_chunk_fn() function, then all unknown
-chunks will be saved when read, in case your callback function will need
-one or more of them.  This behavior can be changed with the
-png_set_keep_unknown_chunks() function, described below.
+chunks which the callback does not handle will be saved when read.  You can
+cause them to be discarded by returning '1' ("handled") instead of '0'.  This
+behavior will change in libpng 1.7 and the default handling set by the
+png_set_keep_unknown_chunks() function, described below, will be used when the
+callback returns 0.  If you want the existing behavior you should set the global
+default to PNG_HANDLE_CHUNK_IF_SAFE now; this is compatible with all current
+versions of libpng and with 1.7.  Libpng 1.6 issues a warning if you keep the
+default, or PNG_HANDLE_CHUNK_NEVER, and the callback returns 0.
 
 At this point, you can set up a callback function that will be
 called after each row has been read, which you can use to control
@@ -629,15 +631,17 @@ callback function:
     ...
 
     #if defined(PNG_UNKNOWN_CHUNKS_SUPPORTED)
-      /* ignore all unknown chunks: */
-      png_set_keep_unknown_chunks(read_ptr, 1, NULL, 0);
+      /* ignore all unknown chunks
+       * (use global setting "2" for libpng16 and earlier):
+       */
+      png_set_keep_unknown_chunks(read_ptr, 2, NULL, 0);
 
       /* except for vpAg: */
       png_set_keep_unknown_chunks(read_ptr, 2, vpAg, 1);
 
       /* also ignore unused known chunks: */
       png_set_keep_unknown_chunks(read_ptr, 1, unused_chunks,
-         (int)sizeof(unused_chunks)/5);
+         (int)(sizeof unused_chunks)/5);
     #endif
 
 User limits
@@ -676,9 +680,6 @@ where 0x7fffffffL means unlimited.  You can retrieve this limit with
 
    chunk_cache_max = png_get_chunk_cache_max(png_ptr);
 
-This limit also applies to the number of buffers that can be allocated
-by png_decompress_chunk() while decompressing iTXt, zTXt, and iCCP chunks.
-
 You can also set a limit on the amount of memory that a compressed chunk
 other than IDAT can occupy, with
 
@@ -992,7 +993,7 @@ where row_pointers is an array of pointers to the pixel data for each row:
 If you know your image size and pixel size ahead of time, you can allocate
 row_pointers prior to calling png_read_png() with
 
-   if (height > PNG_UINT_32_MAX/png_sizeof(png_byte))
+   if (height > PNG_UINT_32_MAX/(sizeof (png_byte)))
       png_error (png_ptr,
           "Image is too tall to process in memory");
 
@@ -1001,7 +1002,7 @@ row_pointers prior to calling png_read_png() with
           "Image is too wide to process in memory");
 
    row_pointers = png_malloc(png_ptr,
-       height*png_sizeof(png_bytep));
+       height*(sizeof (png_bytep)));
 
    for (int i=0; i<height, i++)
       row_pointers[i]=NULL;  /* security precaution */
@@ -2562,9 +2563,9 @@ section below for more information on the libpng error handling.
 
 If you would rather avoid the complexity of setjmp/longjmp issues,
 you can compile libpng with PNG_NO_SETJMP, in which case
-errors will result in a call to PNG_ABORT which defaults to abort().
+errors will result in a call to PNG_ABORT() which defaults to abort().
 
-You can #define PNG_ABORT to a function or other C code that does something
+You can #define PNG_ABORT() to a function that does something
 more useful than abort(), as long as your function does not
 return.
 
@@ -3090,13 +3091,47 @@ a writeable buffer of at least 29 bytes.
 
 Writing unknown chunks
 
-You can use the png_set_unknown_chunks function to queue up chunks
-for writing.  You give it a chunk name, raw data, and a size; that's
-all there is to it.  The chunks will be written by the next following
-png_write_info_before_PLTE, png_write_info, or png_write_end function.
-Any chunks previously read into the info structure's unknown-chunk
-list will also be written out in a sequence that satisfies the PNG
-specification's ordering rules.
+You can use the png_set_unknown_chunks function to queue up private chunks
+for writing.  You give it a chunk name, location, raw data, and a size.  You
+also must use png_set_keep_unknown_chunks() to ensure that libpng will
+handle them.  That's all there is to it.  The chunks will be written by the
+next following png_write_info_before_PLTE, png_write_info, or png_write_end
+function, depending upon the specified location.  Any chunks previously
+read into the info structure's unknown-chunk list will also be written out
+in a sequence that satisfies the PNG specification's ordering rules.
+
+Here is an example of writing two private chunks, prVt and miNE:
+
+    #ifdef PNG_WRITE_UNKNOWN_CHUNKS_SUPPORTED
+    /* Set unknown chunk data */
+    png_unknown_chunk unk_chunk[2];
+    strcpy((char *) unk_chunk[0].name, "prVt";
+    unk_chunk[0].data = (unsigned char *) "PRIVATE DATA";
+    unk_chunk[0].size = strlen(unk_chunk[0].data)+1;
+    unk_chunk[0].location = PNG_HAVE_IHDR;
+    strcpy((char *) unk_chunk[1].name, "miNE";
+    unk_chunk[1].data = (unsigned char *) "MY CHUNK DATA";
+    unk_chunk[1].size = strlen(unk_chunk[0].data)+1;
+    unk_chunk[1].location = PNG_AFTER_IDAT;
+    png_set_unknown_chunks(write_ptr, write_info_ptr,
+        unk_chunk, 2);
+    /* Needed because miNE is not safe-to-copy */
+    png_set_keep_unknown_chunks(png, PNG_HANDLE_CHUNK_ALWAYS,
+       (png_bytep) "miNE", 1);
+    # if PNG_LIBPNG_VER < 10600
+      /* Deal with unknown chunk location bug in 1.5.x and earlier */
+      png_set_unknown_chunk_location(png, info, 0, PNG_HAVE_IHDR);
+      png_set_unknown_chunk_location(png, info, 1, PNG_AFTER_IDAT);
+    # endif
+    # if PNG_LIBPNG_VER < 10500
+      /* PNG_AFTER_IDAT writes two copies of the chunk prior to libpng-1.5.0,
+       * one before IDAT and another after IDAT, so don't use it; only use
+       * PNG_HAVE_IHDR location.  This call resets the location previously
+       * set by assignment and png_set_unknown_chunk_location() for chunk 1.
+       */
+      png_set_unknown_chunk_location(png, info, 1, PNG_HAVE_IHDR);
+    # endif
+    #endif
 
 The high-level write interface
 
@@ -3943,7 +3978,7 @@ Error handling in libpng is done through png_error() and png_warning().
 Errors handled through png_error() are fatal, meaning that png_error()
 should never return to its caller.  Currently, this is handled via
 setjmp() and longjmp() (unless you have compiled libpng with
-PNG_NO_SETJMP, in which case it is handled via PNG_ABORT),
+PNG_NO_SETJMP, in which case it is handled via PNG_ABORT()),
 but you could change this to do things like exit() if you should wish,
 as long as your function does not return.
 
@@ -3985,6 +4020,15 @@ compiler documentation for more details.  For an alternative approach, you
 may wish to use the "cexcept" facility (see http://cexcept.sourceforge.net),
 which is illustrated in pngvalid.c and in contrib/visupng.
 
+Beginning in libpng-1.4.0, the png_set_benign_errors() API became available.
+You can use this to handle certain errors (normally handled as errors)
+as warnings.
+
+    png_set_benign_errors (png_ptr, int allowed);
+
+    allowed: 0: (default) treat png_benign_error() an error.
+             1: treat png_benign_error() as a warning.
+
 Custom chunks
 
 If you need to read or write custom chunks, you may need to get deeper
@@ -4594,6 +4638,18 @@ If the error is ignored, or if png_benign_error() treats it as a warning,
 any invalid pixels are decoded as opaque black by the decoder and written
 as-is by the encoder.
 
+Retrieving the maximum palette index found was added at libpng-1.5.15.
+This statement must appear after png_read_png() or png_read_image() while
+reading, and after png_write_png() or png_write_image() while writing.
+
+   int max_palette = png_get_palette_max(png_ptr, info_ptr);
+
+This will return the maximum palette index found in the image, or "-1" if
+the palette was not checked, or "0" if no palette was found.  Note that this
+does not account for any palette index used by ancillary chunks such as the
+bKGD chunk; you must check those separately to determine the maximum
+palette index actually used.
+
 A. Changes that affect users of libpng
 
 There are no substantial API changes between the non-deprecated parts of
@@ -4923,9 +4979,9 @@ symbols, using the PNG_PREFIX macro.
 
 We no longer include string.h in png.h.  The include statement has been moved
 to pngpriv.h, where it is not accessible by applications.  Applications that
-need access to information in string.h must add an '#include "string.h"'
+need access to information in string.h must add an '#include <string.h>'
 directive.  It does not matter whether this is placed prior to or after
-the '"#include png.h"' directive.
+the '#include "png.h"' directive.
 
 The following API are now DEPRECATED:
    png_info_init_3()
@@ -4954,7 +5010,14 @@ where "rp" indicates a "restricted pointer".
 Error detection in some chunks has improved; in particular the iCCP chunk
 reader now does pretty complete validation of the basic format.  Some bad
 profiles that were previously accepted are now rejected, in particular the
-very old broken Microsoft/HP sRGB profile.
+very old broken Microsoft/HP sRGB profile.  The PNG spec requirement that
+only grayscale profiles may appear in images with color type 0 or 4 and that
+even if the image only contains gray pixels, only RGB profiles may appear
+in images with color type 2, 3, or 6, is now enforced.  The sRGB chunk
+is allowed to appear in images with any color type.
+
+The library now issues an error if the application attempts to set a
+transform after it calls png_read_update_info().
 
 The library now issues a warning if both background processing and RGB to
 gray are used when gamma correction happens. As with previous versions of
@@ -4968,39 +5031,26 @@ This adds more correct option control of the unknown handling, corrects
 a pre-existing bug where the per-chunk 'keep' setting is ignored, and makes
 it possible to skip IDAT chunks in the sequential reader.
 
-XIII.  Changes to Libpng from version 1.6.x to 1.7.x
+The machine-generated configure files are no longer included in branches
+libpng16 and later of the GIT repository.  They continue to be included
+in the tarball releases, however.
 
-Some functions that were deprecated in libpng-1.6.0 were removed:
-    png_reset_zstream(),
-    png_info_init_3(),
-    png_data_freer() and its associated flags,
-    png_malloc_default(),
-    and png_free_default().
+Libpng-1.6.0 and later use the CMF bytes at the beginning of the IDAT stream
+to set the size of the sliding window for reading instead of using the default
+32-kbyte sliding window size.  It was discovered that there are hundreds of PNG
+files in the wild that have incorrect CMF bytes that cause libpng to now issue
+a "too far back" error and reject the file.  Libpng-1.6.3 provides a way to
+revert to the libpng-1.5.x behavior (ignoring the CMF bytes and using a
+32-kbyte sliding window), and provides a tool
+(contrib/tools/png-fix-too-far-back) for optimizing the CMF bytes
+correctly.
 
-The PNG_ABORT() macro was changed to PNG_ABORT, and the default is now
-"abort()" for all platforms (previously it was "ExitProcess(0)" on
-Windows platforms).  Starting with libpng-1.7.0 you have to define
-PNG_ABORT instead of PNG_ABORT(), e.g.,
+Libpng-1.6.0 and libpng-1.6.1 wrote uncompressed iTXt chunks with the wrong
+length, which resulted in PNG files that cannot be read beyond the bad iTXt
+chunk.  This error was fixed in libpng-1.6.3, and a tool (called
+contrib/tools/png-fix-itxt) has been added to the libpng distribution.
 
-    #if PNGCRUSH_LIBPNG_VER >= 10700
-    #  ifdef _WINDOWS_
-    #    define PNG_ABORT ExitProcess(0);
-    #  else
-    #    define PNG_ABORT abort();
-    #  endif
-    #else
-    #  ifdef _WINDOWS_
-    #    define PNG_ABORT() ExitProcess(0)
-    #  else
-    #    define PNG_ABORT() abort()
-    #  endif
-    #endif
-
-The 8-bit compose and rgb_to_grayscale operations were made more accurate.
-While these did not introduce API incompatibility, there may be differences
-in unit test results.
-
-XIV.  Detecting libpng
+XIII.  Detecting libpng
 
 The png_get_io_ptr() function has been present since libpng-0.88, has never
 changed, and is unaffected by conditional compilation macros.  It is the
@@ -5016,11 +5066,11 @@ control.  The git repository was built from old libpng-x.y.z.tar.gz files
 going back to version 0.70.  You can access the git repository (read only)
 at
 
-    git://libpng.git.sourceforge.net/gitroot/libpng
+    git://git.code.sf.net/p/libpng/code
 
-or you can browse it via "gitweb" at
+or you can browse it with a web browser by selecting the "code" button at
 
-    http://libpng.git.sourceforge.net/git/gitweb.cgi?p=libpng
+    https://sourceforge.net/projects/libpng
 
 Patches can be sent to glennrp at users.sourceforge.net or to
 png-mng-implement at lists.sourceforge.net or you can upload them to
@@ -5033,7 +5083,7 @@ simple verbal discriptions of bug fixes, reported either to the
 SourceForge bug tracker, to the png-mng-implement at lists.sf.net
 mailing list, or directly to glennrp.
 
-XVI. Coding style
+XV. Coding style
 
 Our coding style is similar to the "Allman" style, with curly
 braces on separate lines:
@@ -5145,7 +5195,8 @@ left parenthesis that follows it:
        y[i] = a(x) + (int)b;
 
 We prefer #ifdef and #ifndef to #if defined() and #if !defined()
-when there is only one macro being tested.
+when there is only one macro being tested.  We always use parentheses
+with "defined".
 
 We prefer to express integers that are used as bit masks in hex format,
 with an even number of lower-case hex digits (e.g., 0x00, 0xff, 0x0100).
@@ -5159,15 +5210,15 @@ Lines do not exceed 80 characters.
 
 Other rules can be inferred by inspecting the libpng source.
 
-XVII. Y2K Compliance in libpng
+XVI. Y2K Compliance in libpng
 
-January 21, 2013
+May 12, 2013
 
 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 1.7.0alpha09 are Y2K compliant.  It is my belief that earlier
+upward through 1.6.3beta06 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

libpng.3

@@ -1,6 +1,6 @@
-.TH LIBPNG 3 "January 21, 2013"
+.TH LIBPNG 3 "May 12, 2013"
 .SH NAME
-libpng \- Portable Network Graphics (PNG) Reference Library 1.7.0alpha09
+libpng \- Portable Network Graphics (PNG) Reference Library 1.6.3beta06
 .SH SYNOPSIS
 \fB
 #include <png.h>\fP
@@ -23,7 +23,7 @@ libpng \- Portable Network Graphics (PNG) Reference Library 1.7.0alpha09
 
 \fBvoid png_convert_from_time_t (png_timep \fP\fIptime\fP\fB, time_t \fIttime\fP\fB);\fP
 
-\fBpng_charp png_convert_to_rfc1123_buffer (png_structp \fP\fIpng_ptr\fP\fB, char \fP\fIout[29]\fP\fB, png_timep \fIptime\fP\fB);\fP
+\fBpng_charp png_convert_to_rfc1123 (png_structp \fP\fIpng_ptr\fP\fB, png_timep \fIptime\fP\fB);\fP
 
 \fBpng_infop png_create_info_struct (png_structp \fIpng_ptr\fP\fB);\fP
 
@@ -35,6 +35,8 @@ libpng \- Portable Network Graphics (PNG) Reference Library 1.7.0alpha09
 
 \fBpng_structp png_create_write_struct_2 (png_const_charp \fP\fIuser_png_ver\fP\fB, png_voidp \fP\fIerror_ptr\fP\fB, png_error_ptr \fP\fIerror_fn\fP\fB, png_error_ptr \fP\fIwarn_fn\fP\fB, png_voidp \fP\fImem_ptr\fP\fB, png_malloc_ptr \fP\fImalloc_fn\fP\fB, png_free_ptr \fIfree_fn\fP\fB);\fP
 
+\fBvoid png_data_freer (png_structp \fP\fIpng_ptr\fP\fB, png_infop \fP\fIinfo_ptr\fP\fB, int \fP\fIfreer\fP\fB, png_uint_32 \fImask)\fP\fB);\fP
+
 \fBvoid png_destroy_info_struct (png_structp \fP\fIpng_ptr\fP\fB, png_infopp \fIinfo_ptr_ptr\fP\fB);\fP
 
 \fBvoid png_destroy_read_struct (png_structpp \fP\fIpng_ptr_ptr\fP\fB, png_infopp \fP\fIinfo_ptr_ptr\fP\fB, png_infopp \fIend_info_ptr_ptr\fP\fB);\fP
@@ -49,6 +51,8 @@ libpng \- Portable Network Graphics (PNG) Reference Library 1.7.0alpha09
 
 \fBvoid png_free_chunk_list (png_structp \fIpng_ptr\fP\fB);\fP
 
+\fBvoid png_free_default (png_structp \fP\fIpng_ptr\fP\fB, png_voidp \fIptr\fP\fB);\fP
+
 \fBvoid png_free_data (png_structp \fP\fIpng_ptr\fP\fB, png_infop \fP\fIinfo_ptr\fP\fB, int \fInum\fP\fB);\fP
 
 \fBpng_byte png_get_bit_depth (png_const_structp \fP\fIpng_ptr\fP\fB, png_const_infop \fIinfo_ptr\fP\fB);\fP
@@ -225,12 +229,16 @@ libpng \- Portable Network Graphics (PNG) Reference Library 1.7.0alpha09
 
 \fBint png_image_write_to_stdio (png_imagep \fP\fIimage\fP\fB, FILE \fP\fI*file\fP\fB, int \fP\fIconvert_to_8_bit\fP\fB, const void \fP\fI*buffer\fP\fB, png_int_32 \fP\fIrow_stride\fP\fB, void \fI*colormap)\fP\fB);\fP
 
+\fBvoid png_info_init_3 (png_infopp \fP\fIinfo_ptr\fP\fB, png_size_t \fIpng_info_struct_size\fP\fB);\fP
+
 \fBvoid png_init_io (png_structp \fP\fIpng_ptr\fP\fB, FILE \fI*fp\fP\fB);\fP
 
 \fBvoid png_longjmp (png_structp \fP\fIpng_ptr\fP\fB, int \fIval\fP\fB);\fP
 
 \fBpng_voidp png_malloc (png_structp \fP\fIpng_ptr\fP\fB, png_alloc_size_t \fIsize\fP\fB);\fP
 
+\fBpng_voidp png_malloc_default (png_structp \fP\fIpng_ptr\fP\fB, png_alloc_size_t \fIsize\fP\fB);\fP
+
 \fBpng_voidp png_malloc_warn (png_structp \fP\fIpng_ptr\fP\fB, png_alloc_size_t \fIsize\fP\fB);\fP
 
 \fBpng_uint_32 png_permit_mng_features (png_structp \fP\fIpng_ptr\fP\fB, png_uint_32 \fImng_features_permitted\fP\fB);\fP
@@ -257,6 +265,8 @@ libpng \- Portable Network Graphics (PNG) Reference Library 1.7.0alpha09
 
 \fBvoid png_read_update_info (png_structp \fP\fIpng_ptr\fP\fB, png_infop \fIinfo_ptr\fP\fB);\fP
 
+\fBint png_reset_zstream (png_structp \fIpng_ptr\fP\fB);\fP
+
 \fBvoid png_save_int_32 (png_bytep \fP\fIbuf\fP\fB, png_int_32 \fIi\fP\fB);\fP
 
 \fBvoid png_save_uint_16 (png_bytep \fP\fIbuf\fP\fB, unsigned int \fIi\fP\fB);\fP
@@ -494,7 +504,7 @@ Following is a copy of the libpng-manual.txt file that accompanies libpng.
 .SH LIBPNG.TXT
 libpng-manual.txt - A description on how to use and modify libpng
 
- libpng version 1.7.0alpha09 - January 21, 2013
+ libpng version 1.6.3beta06 - May 12, 2013
  Updated and distributed by Glenn Randers-Pehrson
  <glennrp at users.sourceforge.net>
  Copyright (c) 1998-2013 Glenn Randers-Pehrson
@@ -505,9 +515,9 @@ libpng-manual.txt - A description on how to use and modify libpng
 
  Based on:
 
- libpng versions 0.97, January 1998, through 1.7.0alpha09 - January 21, 2013
+ libpng versions 0.97, January 1998, through 1.6.3beta06 - May 12, 2013
  Updated and distributed by Glenn Randers-Pehrson
- Copyright (c) 1998-2011 Glenn Randers-Pehrson
+ Copyright (c) 1998-2013 Glenn Randers-Pehrson
 
  libpng 1.0 beta 6  version 0.96 May 28, 1997
  Updated and distributed by Andreas Dilger
@@ -536,18 +546,15 @@ libpng-manual.txt - A description on how to use and modify libpng
     X. Changes to Libpng from version 1.0.x/1.2.x to 1.4.x
    XI. Changes to Libpng from version 1.4.x to 1.5.x
   XII. Changes to Libpng from version 1.5.x to 1.6.x
- XIII. Changes to Libpng from version 1.6.x to 1.7.x
-  XIV. Detecting libpng
-   XV. Source code repository
-  XVI. Coding style
- XVII. Y2K Compliance in libpng
+ XIII. Detecting libpng
+  XIV. Source code repository
+   XV. Coding style
+  XVI. Y2K Compliance in libpng
 
 .SH I. Introduction
 
 This file describes how to use and modify the PNG reference library
-(known as libpng) for your own use.  There are five sections to this
-file: introduction, structures, reading, writing, and modification and
-configuration notes for various special platforms.  In addition to this
+(known as libpng) for your own use.  In addition to this
 file, example.c is a good starting point for using the library, as
 it is heavily commented and should include everything most people
 will need.  We assume that libpng is already installed; see the
@@ -926,7 +933,7 @@ If you would rather avoid the complexity of setjmp/longjmp issues,
 you can compile libpng with PNG_NO_SETJMP, in which case
 errors will result in a call to PNG_ABORT() which defaults to abort().
 
-You can #define PNG_ABORT to a function or other C code that does something
+You can #define PNG_ABORT() to a function that does something
 more useful than abort(), as long as your function does not
 return.
 
@@ -1022,9 +1029,14 @@ you can retrieve with
     png_get_user_chunk_ptr(png_ptr);
 
 If you call the png_set_read_user_chunk_fn() function, then all unknown
-chunks will be saved when read, in case your callback function will need
-one or more of them.  This behavior can be changed with the
-png_set_keep_unknown_chunks() function, described below.
+chunks which the callback does not handle will be saved when read.  You can
+cause them to be discarded by returning '1' ("handled") instead of '0'.  This
+behavior will change in libpng 1.7 and the default handling set by the
+png_set_keep_unknown_chunks() function, described below, will be used when the
+callback returns 0.  If you want the existing behavior you should set the global
+default to PNG_HANDLE_CHUNK_IF_SAFE now; this is compatible with all current
+versions of libpng and with 1.7.  Libpng 1.6 issues a warning if you keep the
+default, or PNG_HANDLE_CHUNK_NEVER, and the callback returns 0.
 
 At this point, you can set up a callback function that will be
 called after each row has been read, which you can use to control
@@ -1123,15 +1135,17 @@ callback function:
     ...
 
     #if defined(PNG_UNKNOWN_CHUNKS_SUPPORTED)
-      /* ignore all unknown chunks: */
-      png_set_keep_unknown_chunks(read_ptr, 1, NULL, 0);
+      /* ignore all unknown chunks
+       * (use global setting "2" for libpng16 and earlier):
+       */
+      png_set_keep_unknown_chunks(read_ptr, 2, NULL, 0);
 
       /* except for vpAg: */
       png_set_keep_unknown_chunks(read_ptr, 2, vpAg, 1);
 
       /* also ignore unused known chunks: */
       png_set_keep_unknown_chunks(read_ptr, 1, unused_chunks,
-         (int)sizeof(unused_chunks)/5);
+         (int)(sizeof unused_chunks)/5);
     #endif
 
 .SS User limits
@@ -1170,9 +1184,6 @@ where 0x7fffffffL means unlimited.  You can retrieve this limit with
 
    chunk_cache_max = png_get_chunk_cache_max(png_ptr);
 
-This limit also applies to the number of buffers that can be allocated
-by png_decompress_chunk() while decompressing iTXt, zTXt, and iCCP chunks.
-
 You can also set a limit on the amount of memory that a compressed chunk
 other than IDAT can occupy, with
 
@@ -1486,7 +1497,7 @@ where row_pointers is an array of pointers to the pixel data for each row:
 If you know your image size and pixel size ahead of time, you can allocate
 row_pointers prior to calling png_read_png() with
 
-   if (height > PNG_UINT_32_MAX/png_sizeof(png_byte))
+   if (height > PNG_UINT_32_MAX/(sizeof (png_byte)))
       png_error (png_ptr,
           "Image is too tall to process in memory");
 
@@ -1495,7 +1506,7 @@ row_pointers prior to calling png_read_png() with
           "Image is too wide to process in memory");
 
    row_pointers = png_malloc(png_ptr,
-       height*png_sizeof(png_bytep));
+       height*(sizeof (png_bytep)));
 
    for (int i=0; i<height, i++)
       row_pointers[i]=NULL;  /* security precaution */
@@ -3056,9 +3067,9 @@ section below for more information on the libpng error handling.
 
 If you would rather avoid the complexity of setjmp/longjmp issues,
 you can compile libpng with PNG_NO_SETJMP, in which case
-errors will result in a call to PNG_ABORT which defaults to abort().
+errors will result in a call to PNG_ABORT() which defaults to abort().
 
-You can #define PNG_ABORT to a function or other C code that does something
+You can #define PNG_ABORT() to a function that does something
 more useful than abort(), as long as your function does not
 return.
 
@@ -3584,13 +3595,47 @@ a writeable buffer of at least 29 bytes.
 
 .SS Writing unknown chunks
 
-You can use the png_set_unknown_chunks function to queue up chunks
-for writing.  You give it a chunk name, raw data, and a size; that's
-all there is to it.  The chunks will be written by the next following
-png_write_info_before_PLTE, png_write_info, or png_write_end function.
-Any chunks previously read into the info structure's unknown-chunk
-list will also be written out in a sequence that satisfies the PNG
-specification's ordering rules.
+You can use the png_set_unknown_chunks function to queue up private chunks
+for writing.  You give it a chunk name, location, raw data, and a size.  You
+also must use png_set_keep_unknown_chunks() to ensure that libpng will
+handle them.  That's all there is to it.  The chunks will be written by the
+next following png_write_info_before_PLTE, png_write_info, or png_write_end
+function, depending upon the specified location.  Any chunks previously
+read into the info structure's unknown-chunk list will also be written out
+in a sequence that satisfies the PNG specification's ordering rules.
+
+Here is an example of writing two private chunks, prVt and miNE:
+
+    #ifdef PNG_WRITE_UNKNOWN_CHUNKS_SUPPORTED
+    /* Set unknown chunk data */
+    png_unknown_chunk unk_chunk[2];
+    strcpy((char *) unk_chunk[0].name, "prVt";
+    unk_chunk[0].data = (unsigned char *) "PRIVATE DATA";
+    unk_chunk[0].size = strlen(unk_chunk[0].data)+1;
+    unk_chunk[0].location = PNG_HAVE_IHDR;
+    strcpy((char *) unk_chunk[1].name, "miNE";
+    unk_chunk[1].data = (unsigned char *) "MY CHUNK DATA";
+    unk_chunk[1].size = strlen(unk_chunk[0].data)+1;
+    unk_chunk[1].location = PNG_AFTER_IDAT;
+    png_set_unknown_chunks(write_ptr, write_info_ptr,
+        unk_chunk, 2);
+    /* Needed because miNE is not safe-to-copy */
+    png_set_keep_unknown_chunks(png, PNG_HANDLE_CHUNK_ALWAYS,
+       (png_bytep) "miNE", 1);
+    # if PNG_LIBPNG_VER < 10600
+      /* Deal with unknown chunk location bug in 1.5.x and earlier */
+      png_set_unknown_chunk_location(png, info, 0, PNG_HAVE_IHDR);
+      png_set_unknown_chunk_location(png, info, 1, PNG_AFTER_IDAT);
+    # endif
+    # if PNG_LIBPNG_VER < 10500
+      /* PNG_AFTER_IDAT writes two copies of the chunk prior to libpng-1.5.0,
+       * one before IDAT and another after IDAT, so don't use it; only use
+       * PNG_HAVE_IHDR location.  This call resets the location previously
+       * set by assignment and png_set_unknown_chunk_location() for chunk 1.
+       */
+      png_set_unknown_chunk_location(png, info, 1, PNG_HAVE_IHDR);
+    # endif
+    #endif
 
 .SS The high-level write interface
 
@@ -4437,7 +4482,7 @@ Error handling in libpng is done through png_error() and png_warning().
 Errors handled through png_error() are fatal, meaning that png_error()
 should never return to its caller.  Currently, this is handled via
 setjmp() and longjmp() (unless you have compiled libpng with
-PNG_NO_SETJMP, in which case it is handled via PNG_ABORT),
+PNG_NO_SETJMP, in which case it is handled via PNG_ABORT()),
 but you could change this to do things like exit() if you should wish,
 as long as your function does not return.
 
@@ -4479,6 +4524,15 @@ compiler documentation for more details.  For an alternative approach, you
 may wish to use the "cexcept" facility (see http://cexcept.sourceforge.net),
 which is illustrated in pngvalid.c and in contrib/visupng.
 
+Beginning in libpng-1.4.0, the png_set_benign_errors() API became available.
+You can use this to handle certain errors (normally handled as errors)
+as warnings.
+
+    png_set_benign_errors (png_ptr, int allowed);
+
+    allowed: 0: (default) treat png_benign_error() an error.
+             1: treat png_benign_error() as a warning.
+
 .SS Custom chunks
 
 If you need to read or write custom chunks, you may need to get deeper
@@ -5089,6 +5143,18 @@ If the error is ignored, or if png_benign_error() treats it as a warning,
 any invalid pixels are decoded as opaque black by the decoder and written
 as-is by the encoder.
 
+Retrieving the maximum palette index found was added at libpng-1.5.15.
+This statement must appear after png_read_png() or png_read_image() while
+reading, and after png_write_png() or png_write_image() while writing.
+
+   int max_palette = png_get_palette_max(png_ptr, info_ptr);
+
+This will return the maximum palette index found in the image, or "-1" if
+the palette was not checked, or "0" if no palette was found.  Note that this
+does not account for any palette index used by ancillary chunks such as the
+bKGD chunk; you must check those separately to determine the maximum
+palette index actually used.
+
 A. Changes that affect users of libpng
 
 There are no substantial API changes between the non-deprecated parts of
@@ -5418,9 +5484,9 @@ symbols, using the PNG_PREFIX macro.
 
 We no longer include string.h in png.h.  The include statement has been moved
 to pngpriv.h, where it is not accessible by applications.  Applications that
-need access to information in string.h must add an '#include "string.h"'
+need access to information in string.h must add an '#include <string.h>'
 directive.  It does not matter whether this is placed prior to or after
-the '"#include png.h"' directive.
+the '#include "png.h"' directive.
 
 The following API are now DEPRECATED:
    png_info_init_3()
@@ -5449,7 +5515,14 @@ where "rp" indicates a "restricted pointer".
 Error detection in some chunks has improved; in particular the iCCP chunk
 reader now does pretty complete validation of the basic format.  Some bad
 profiles that were previously accepted are now rejected, in particular the
-very old broken Microsoft/HP sRGB profile.
+very old broken Microsoft/HP sRGB profile.  The PNG spec requirement that
+only grayscale profiles may appear in images with color type 0 or 4 and that
+even if the image only contains gray pixels, only RGB profiles may appear
+in images with color type 2, 3, or 6, is now enforced.  The sRGB chunk
+is allowed to appear in images with any color type.
+
+The library now issues an error if the application attempts to set a
+transform after it calls png_read_update_info().
 
 The library now issues a warning if both background processing and RGB to
 gray are used when gamma correction happens. As with previous versions of
@@ -5463,39 +5536,26 @@ This adds more correct option control of the unknown handling, corrects
 a pre-existing bug where the per-chunk 'keep' setting is ignored, and makes
 it possible to skip IDAT chunks in the sequential reader.
 
-.SH XIII.  Changes to Libpng from version 1.6.x to 1.7.x
+The machine-generated configure files are no longer included in branches
+libpng16 and later of the GIT repository.  They continue to be included
+in the tarball releases, however.
 
-Some functions that were deprecated in libpng-1.6.0 were removed:
-    png_reset_zstream(),
-    png_info_init_3(),
-    png_data_freer() and its associated flags,
-    png_malloc_default(),
-    and png_free_default().
+Libpng-1.6.0 and later use the CMF bytes at the beginning of the IDAT stream
+to set the size of the sliding window for reading instead of using the default
+32-kbyte sliding window size.  It was discovered that there are hundreds of PNG
+files in the wild that have incorrect CMF bytes that cause libpng to now issue
+a "too far back" error and reject the file.  Libpng-1.6.3 provides a way to
+revert to the libpng-1.5.x behavior (ignoring the CMF bytes and using a
+32-kbyte sliding window), and provides a tool
+(contrib/tools/png-fix-too-far-back) for optimizing the CMF bytes
+correctly.
 
-The PNG_ABORT() macro was changed to PNG_ABORT, and the default is now
-"abort()" for all platforms (previously it was "ExitProcess(0)" on
-Windows platforms).  Starting with libpng-1.7.0 you have to define
-PNG_ABORT instead of PNG_ABORT(), e.g.,
+Libpng-1.6.0 and libpng-1.6.1 wrote uncompressed iTXt chunks with the wrong
+length, which resulted in PNG files that cannot be read beyond the bad iTXt
+chunk.  This error was fixed in libpng-1.6.3, and a tool (called
+contrib/tools/png-fix-itxt) has been added to the libpng distribution.
 
-    #if PNGCRUSH_LIBPNG_VER >= 10700
-    #  ifdef _WINDOWS_
-    #    define PNG_ABORT ExitProcess(0);
-    #  else
-    #    define PNG_ABORT abort();
-    #  endif
-    #else
-    #  ifdef _WINDOWS_
-    #    define PNG_ABORT() ExitProcess(0)
-    #  else
-    #    define PNG_ABORT() abort()
-    #  endif
-    #endif
-
-The 8-bit compose and rgb_to_grayscale operations were made more accurate.
-While these did not introduce API incompatibility, there may be differences
-in unit test results.
-
-.SH XIV.  Detecting libpng
+.SH XIII.  Detecting libpng
 
 The png_get_io_ptr() function has been present since libpng-0.88, has never
 changed, and is unaffected by conditional compilation macros.  It is the
@@ -5511,11 +5571,11 @@ control.  The git repository was built from old libpng-x.y.z.tar.gz files
 going back to version 0.70.  You can access the git repository (read only)
 at
 
-    git://libpng.git.sourceforge.net/gitroot/libpng
+    git://git.code.sf.net/p/libpng/code
 
-or you can browse it via "gitweb" at
+or you can browse it with a web browser by selecting the "code" button at
 
-    http://libpng.git.sourceforge.net/git/gitweb.cgi?p=libpng
+    https://sourceforge.net/projects/libpng
 
 Patches can be sent to glennrp at users.sourceforge.net or to
 png-mng-implement at lists.sourceforge.net or you can upload them to
@@ -5528,7 +5588,7 @@ simple verbal discriptions of bug fixes, reported either to the
 SourceForge bug tracker, to the png-mng-implement at lists.sf.net
 mailing list, or directly to glennrp.
 
-.SH XVI. Coding style
+.SH XV. Coding style
 
 Our coding style is similar to the "Allman" style, with curly
 braces on separate lines:
@@ -5640,7 +5700,8 @@ left parenthesis that follows it:
        y[i] = a(x) + (int)b;
 
 We prefer #ifdef and #ifndef to #if defined() and #if !defined()
-when there is only one macro being tested.
+when there is only one macro being tested.  We always use parentheses
+with "defined".
 
 We prefer to express integers that are used as bit masks in hex format,
 with an even number of lower-case hex digits (e.g., 0x00, 0xff, 0x0100).
@@ -5654,15 +5715,15 @@ Lines do not exceed 80 characters.
 
 Other rules can be inferred by inspecting the libpng source.
 
-.SH XVII. Y2K Compliance in libpng
+.SH XVI. Y2K Compliance in libpng
 
-January 21, 2013
+May 12, 2013
 
 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 1.7.0alpha09 are Y2K compliant.  It is my belief that earlier
+upward through 1.6.3beta06 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
@@ -5867,8 +5928,16 @@ the first widely used release:
  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]
- 1.6.0beta01-37      16    10600  16.so.16.0[.0]
- 1.7.0alpha01-09     17    10700  17.so.17.0[.0]
+ 1.6.0beta01-40      16    10600  16.so.16.0[.0]
+ 1.6.0rc01-08        16    10600  16.so.16.0[.0]
+ 1.6.0               16    10600  16.so.16.0[.0]
+ 1.6.1beta01-09      16    10601  16.so.16.1[.0]
+ 1.6.1rc01           16    10601  16.so.16.1[.0]
+ 1.6.1               16    10601  16.so.16.1[.0]
+ 1.6.2beta01         16    10602  16.so.16.2[.0]
+ 1.6.2rc01-06        16    10602  16.so.16.2[.0]
+ 1.6.2               16    10602  16.so.16.2[.0]
+ 1.6.3beta01-06      16    10603  16.so.16.3[.0]
 
 Henceforth the source version will match the shared-library minor
 and patch numbers; the shared-library major version number will be
@@ -5925,7 +5994,7 @@ possible without all of you.
 
 Thanks to Frank J. T. Wojcik for helping with the documentation.
 
-Libpng version 1.7.0alpha09 - January 21, 2013:
+Libpng version 1.6.3beta06 - May 12, 2013:
 Initially created in 1995 by Guy Eric Schalnat, then of Group 42, Inc.
 Currently maintained by Glenn Randers-Pehrson (glennrp at users.sourceforge.net).
 
@@ -5948,7 +6017,7 @@ this sentence.
 
 This code is released under the libpng license.
 
-libpng versions 1.2.6, August 15, 2004, through 1.7.0alpha09, January 21, 2013, are
+libpng versions 1.2.6, August 15, 2004, through 1.6.3beta06, May 12, 2013, are
 Copyright (c) 2004,2006-2007 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
@@ -6047,7 +6116,7 @@ certification mark of the Open Source Initiative.
 
 Glenn Randers-Pehrson
 glennrp at users.sourceforge.net
-January 21, 2013
+May 12, 2013
 
 .\" end of man page
 

libpngpf.3

@@ -1,6 +1,6 @@
-.TH LIBPNGPF 3 "January 21, 2013"
+.TH LIBPNGPF 3 "May 12, 2013"
 .SH NAME
-libpng \- Portable Network Graphics (PNG) Reference Library 1.7.0alpha09
+libpng \- Portable Network Graphics (PNG) Reference Library 1.6.3beta06
 (private functions)
 .SH SYNOPSIS
 \fB#include \fI"pngpriv.h"

png.5

@@ -1,4 +1,4 @@
-.TH PNG 5 "January 21, 2013"
+.TH PNG 5 "May 12, 2013"
 .SH NAME
 png \- Portable Network Graphics (PNG) format
 .SH DESCRIPTION
@@ -24,7 +24,6 @@ PNG specification (second edition), November 2003:
 .IP
 .br
   <http://www.w3.org/TR/2003/REC-PNG-20031110/
-.LP
 PNG 1.2 specification, July 1999:
 .IP
 .br
@@ -59,7 +58,7 @@ Thomas Boutell and others (png-list).
 
 .SH COPYRIGHT NOTICE
 .LP
-This man page is Copyright (c) 1998-2012 Glenn Randers-Pehrson.  See png.h
+This man page is Copyright (c) 1998-2006 Glenn Randers-Pehrson.  See png.h
 for conditions of use and distribution.
 .LP
 The PNG Specification (Second Edition) is

png.h

@@ -1,7 +1,7 @@
 
 /* png.h - header file for PNG reference library
  *
- * libpng version 1.7.0alpha09 - January 21, 2013
+ * libpng version 1.6.3beta06 - May 12, 2013
  * Copyright (c) 1998-2013 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.)
@@ -11,7 +11,7 @@
  * 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 1.7.0alpha09 - January 21, 2013: Glenn
+ *   libpng versions 0.97, January 1998, through 1.6.3beta06 - May 12, 2013: Glenn
  *   See also "Contributing Authors", below.
  *
  * Note about libpng version numbers:
@@ -166,8 +166,16 @@
  *    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]
- *    1.6.0beta01-37          16    10600  16.so.16.0[.0]
- *    1.7.0alpha01-09         17    10700  17.so.17.0[.0]
+ *    1.6.0beta01-40          16    10600  16.so.16.0[.0]
+ *    1.6.0rc01-08            16    10600  16.so.16.0[.0]
+ *    1.6.0                   16    10600  16.so.16.0[.0]
+ *    1.6.1beta01-09          16    10601  16.so.16.1[.0]
+ *    1.6.1rc01               16    10601  16.so.16.1[.0]
+ *    1.6.1                   16    10601  16.so.16.1[.0]
+ *    1.6.2beta01             16    10602  16.so.16.2[.0]
+ *    1.6.2rc01-06            16    10602  16.so.16.2[.0]
+ *    1.6.2                   16    10602  16.so.16.2[.0]
+ *    1.6.3beta01-06          16    10603  16.so.16.3[.0]
  *
  *   Henceforth the source version will match the shared-library major
  *   and minor numbers; the shared-library major version number will be
@@ -199,7 +207,7 @@
  *
  * This code is released under the libpng license.
  *
- * libpng versions 1.2.6, August 15, 2004, through 1.7.0alpha09, January 21, 2013, are
+ * libpng versions 1.2.6, August 15, 2004, through 1.6.3beta06, May 12, 2013, are
  * Copyright (c) 2004, 2006-2013 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:
@@ -311,13 +319,13 @@
  * Y2K compliance in libpng:
  * =========================
  *
- *    January 21, 2013
+ *    May 12, 2013
  *
  *    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 1.7.0alpha09 are Y2K compliant.  It is my belief that
+ *    upward through 1.6.3beta06 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
@@ -377,23 +385,23 @@
  */
 
 /* Version information for png.h - this should match the version in png.c */
-#define PNG_LIBPNG_VER_STRING "1.7.0alpha09"
+#define PNG_LIBPNG_VER_STRING "1.6.3beta06"
 #define PNG_HEADER_VERSION_STRING \
-     " libpng version 1.7.0alpha09 - January 21, 2013\n"
+     " libpng version 1.6.3beta06 - May 12, 2013\n"
 
-#define PNG_LIBPNG_VER_SONUM   17
-#define PNG_LIBPNG_VER_DLLNUM  17
+#define PNG_LIBPNG_VER_SONUM   16
+#define PNG_LIBPNG_VER_DLLNUM  16
 
 /* These should match the first 3 components of PNG_LIBPNG_VER_STRING: */
 #define PNG_LIBPNG_VER_MAJOR   1
-#define PNG_LIBPNG_VER_MINOR   7
-#define PNG_LIBPNG_VER_RELEASE 0
+#define PNG_LIBPNG_VER_MINOR   6
+#define PNG_LIBPNG_VER_RELEASE 3
 
 /* This should match the numeric part of the final component of
  * PNG_LIBPNG_VER_STRING, omitting any leading zero:
  */
 
-#define PNG_LIBPNG_VER_BUILD  09
+#define PNG_LIBPNG_VER_BUILD  06
 
 /* Release Status */
 #define PNG_LIBPNG_BUILD_ALPHA    1
@@ -410,7 +418,7 @@
 #define PNG_LIBPNG_BUILD_SPECIAL 32 /* Cannot be OR'ed with
                                        PNG_LIBPNG_BUILD_PRIVATE */
 
-#define PNG_LIBPNG_BUILD_BASE_TYPE PNG_LIBPNG_BUILD_ALPHA
+#define PNG_LIBPNG_BUILD_BASE_TYPE PNG_LIBPNG_BUILD_BETA
 
 /* Careful here.  At one time, Guy wanted to use 082, but that would be octal.
  * We must not include leading zeros.
@@ -418,7 +426,7 @@
  * 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 10700 /* 1.7.0 */
+#define PNG_LIBPNG_VER 10603 /* 1.6.3 */
 
 /* Library configuration: these options cannot be changed after
  * the library has been built.
@@ -523,7 +531,7 @@ extern "C" {
 /* 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_7_0alpha09;
+typedef char* png_libpng_version_1_6_3beta06;
 
 /* Basic control structions.  Read libpng-manual.txt or libpng.3 for more info.
  *
@@ -1055,8 +1063,8 @@ PNG_EXPORTA(9, void, png_longjmp, (png_const_structrp png_ptr, int val),
     PNG_NORETURN);
 
 #ifdef PNG_READ_SUPPORTED
-/* Reset the compression stream -- Removed from libpng-1.7.0 */
-PNG_REMOVED(10, int, png_reset_zstream, (png_structrp png_ptr), PNG_DEPRECATED)
+/* Reset the compression stream */
+PNG_EXPORTA(10, int, png_reset_zstream, (png_structrp png_ptr), PNG_DEPRECATED);
 #endif
 
 /* New functions added in libpng-1.0.2 (not enabled by default until 1.2.0) */
@@ -1095,9 +1103,12 @@ PNG_EXPORT(17, void, png_write_chunk_end, (png_structrp png_ptr));
 PNG_EXPORTA(18, png_infop, png_create_info_struct, (png_const_structrp png_ptr),
     PNG_ALLOCATED);
 
-/* Removed from libpng-1.7.0 */
-PNG_REMOVED(19, void, png_info_init_3, (png_infopp info_ptr,
-    png_size_t png_info_struct_size), PNG_DEPRECATED)
+/* DEPRECATED: this function allowed init structures to be created using the
+ * default allocation method (typically malloc).  Use is deprecated in 1.6.0 and
+ * the API will be removed in the future.
+ */
+PNG_EXPORTA(19, void, png_info_init_3, (png_infopp info_ptr,
+    png_size_t png_info_struct_size), PNG_DEPRECATED);
 
 /* Writes all the PNG information before the image. */
 PNG_EXPORT(20, void, png_write_info_before_PLTE,
@@ -1114,10 +1125,13 @@ PNG_EXPORT(22, void, png_read_info,
 #ifdef PNG_TIME_RFC1123_SUPPORTED
    /* Convert to a US string format: there is no localization support in this
     * routine.  The original implementation used a 29 character buffer in
-    * png_struct, this has been removed (in libpng 1.7.0).
+    * png_struct, this will be removed in future versions.
     */
-PNG_REMOVED(23, png_const_charp, png_convert_to_rfc1123, (png_structrp png_ptr,
-    png_const_timep ptime),PNG_DEPRECATED)
+#if PNG_LIBPNG_VER < 10700
+/* To do: remove this from libpng17 (and from libpng17/png.c and pngstruct.h) */
+PNG_EXPORTA(23, png_const_charp, png_convert_to_rfc1123, (png_structrp png_ptr,
+    png_const_timep ptime),PNG_DEPRECATED);
+#endif
 PNG_EXPORT(241, int, png_convert_to_rfc1123_buffer, (char out[29],
     png_const_timep ptime));
 #endif
@@ -1614,8 +1628,22 @@ PNG_EXPORT(66, void, png_set_crc_action, (png_structrp png_ptr, int crit_action,
 PNG_EXPORT(67, void, png_set_filter, (png_structrp 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 match the values in the PNG specification.
+ * These defines should NOT be changed.
  */
 #define PNG_FILTER_VALUE_NONE  0
 #define PNG_FILTER_VALUE_SUB   1
@@ -1624,26 +1652,6 @@ PNG_EXPORT(67, void, png_set_filter, (png_structrp png_ptr, int method,
 #define PNG_FILTER_VALUE_PAETH 4
 #define PNG_FILTER_VALUE_LAST  5
 
-/* The above values are valid arguments to png_set_filter() if only a single
- * filter is to be used.  If multiple filters are to be allowed (the default is
- * to allow any of them) then a combination of the following masks must be used
- * and the low three bits of the argument to png_set_filter must be 0.
- *
- * The resultant argument fits in a single byte.
- */
-#define PNG_FILTER_NONE    (0x08 << PNG_FILTER_VALUE_NONE)
-#define PNG_FILTER_SUB     (0x08 << PNG_FILTER_VALUE_SUB)
-#define PNG_FILTER_UP      (0x08 << PNG_FILTER_VALUE_UP)
-#define PNG_FILTER_AVG     (0x08 << PNG_FILTER_VALUE_AVG)
-#define PNG_FILTER_PAETH   (0x08 << PNG_FILTER_VALUE_PAETH)
-
-/* Then two convenience values.  PNG_NO_FILTERS is the same as
- * PNG_FILTER_VALUE_NONE, but this is harmless because they mean the same thing.
- */
-#define PNG_NO_FILTERS     0x00
-#define PNG_ALL_FILTERS    (PNG_FILTER_NONE | PNG_FILTER_SUB | PNG_FILTER_UP | \
-   PNG_FILTER_AVG | PNG_FILTER_PAETH)
-
 #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
@@ -1836,7 +1844,7 @@ PNG_EXPORT(218, png_byte, png_get_current_pass_number, (png_const_structrp));
 #endif
 
 #ifdef PNG_READ_USER_CHUNKS_SUPPORTED
-/* This callback is called only for *unknown* chunks, if
+/* This callback is called only for *unknown* chunks.  If
  * PNG_HANDLE_AS_UNKNOWN_SUPPORTED is set then it is possible to set known
  * chunks to be treated as unknown, however in this case the callback must do
  * any processing required by the chunk (e.g. by calling the appropriate
@@ -1848,12 +1856,12 @@ PNG_EXPORT(218, png_byte, png_get_current_pass_number, (png_const_structrp));
  * The integer return from the callback function is interpreted thus:
  *
  * negative: An error occured, png_chunk_error will be called.
- *     zero: The chunk was not handled, the chunk will be discarded unless
- *           png_set_keep_unknown_chunks has been used to set a 'keep' behavior
- *           for this particular chunk, in which case that will be used.  A
- *           critical chunk will cause an error at this point unless it is to be
- *           saved.
+ *     zero: The chunk was not handled, the chunk will be saved. A critical
+ *           chunk will cause an error at this point unless it is to be saved.
  * positive: The chunk was handled, libpng will ignore/discard it.
+ *
+ * See "INTERACTION WTIH USER CHUNK CALLBACKS" below for important notes about
+ * how this behavior will change in libpng 1.7
  */
 PNG_EXPORT(88, void, png_set_read_user_chunk_fn, (png_structrp png_ptr,
     png_voidp user_chunk_ptr, png_user_chunk_ptr read_user_chunk_fn));
@@ -1929,13 +1937,16 @@ PNG_EXPORT(98, void, png_free_data, (png_const_structrp png_ptr,
  * in, it does not change the state for other png_info structures.
  *
  * It is unlikely that this function works correctly as of 1.6.0 and using it
- * may result either in memory leaks or double free of allocated data. It was
- * removed in libpng 1.7.0.
+ * may result either in memory leaks or double free of allocated data.
  */
-PNG_REMOVED(99, void, png_data_freer, (png_const_structrp png_ptr,
-    png_inforp info_ptr, int freer, png_uint_32 mask), PNG_DEPRECATED)
+PNG_EXPORTA(99, void, png_data_freer, (png_const_structrp png_ptr,
+    png_inforp info_ptr, int freer, png_uint_32 mask), PNG_DEPRECATED);
 
-/* Flags for png_free_data */
+/* 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
@@ -1953,14 +1964,10 @@ PNG_REMOVED(99, void, png_data_freer, (png_const_structrp png_ptr,
 #define PNG_FREE_MUL  0x4220 /* PNG_FREE_SPLT|PNG_FREE_TEXT|PNG_FREE_UNKN */
 
 #ifdef PNG_USER_MEM_SUPPORTED
-   /* These were deprecated in libpng 1.6.0 and have been removed from libpng
-    * 1.7.0; the functionality should be accessed by calling malloc or free
-    * directly or, if png_error handling is required, calling png_malloc.
-    */
-PNG_REMOVED(100, png_voidp, png_malloc_default, (png_const_structrp png_ptr,
-    png_alloc_size_t size), PNG_ALLOCATED PNG_DEPRECATED)
-PNG_REMOVED(101, void, png_free_default, (png_const_structrp png_ptr,
-    png_voidp ptr), PNG_DEPRECATED)
+PNG_EXPORTA(100, png_voidp, png_malloc_default, (png_const_structrp png_ptr,
+    png_alloc_size_t size), PNG_ALLOCATED PNG_DEPRECATED);
+PNG_EXPORTA(101, void, png_free_default, (png_const_structrp png_ptr,
+    png_voidp ptr), PNG_DEPRECATED);
 #endif
 
 #ifdef PNG_ERROR_TEXT_SUPPORTED
@@ -2329,14 +2336,15 @@ PNG_EXPORT(167, void, png_set_tRNS, (png_structrp png_ptr,
 #endif
 
 #ifdef PNG_sCAL_SUPPORTED
-#ifdef PNG_FLOATING_ARITHMETIC_SUPPORTED
-/* NOTE: these API are currently implemented using floating point arithmetic,
- * consequently they can only be used on systems with floating point support.
+PNG_FP_EXPORT(168, png_uint_32, png_get_sCAL, (png_const_structrp png_ptr,
+    png_const_inforp info_ptr, int *unit, double *width, double *height))
+#if defined(PNG_FLOATING_ARITHMETIC_SUPPORTED) || \
+   defined(PNG_FLOATING_POINT_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_FP_EXPORT(168, png_uint_32, png_get_sCAL, (png_const_structrp png_ptr,
-    png_const_inforp info_ptr, int *unit, double *width, double *height))
 PNG_FIXED_EXPORT(214, png_uint_32, png_get_sCAL_fixed,
     (png_const_structrp png_ptr, png_const_inforp info_ptr, int *unit,
     png_fixed_point *width, png_fixed_point *height))
@@ -2345,13 +2353,8 @@ PNG_EXPORT(169, png_uint_32, png_get_sCAL_s,
     (png_const_structrp png_ptr, png_const_inforp info_ptr, int *unit,
     png_charpp swidth, png_charpp sheight));
 
-#ifdef PNG_FLOATING_ARITHMETIC_SUPPORTED
-/* This also requires internal floating point arithmetic support - i.e. it
- * requires a full math library, not just floating point handling.
- */
 PNG_FP_EXPORT(170, void, png_set_sCAL, (png_const_structrp png_ptr,
     png_inforp info_ptr, int unit, double width, double height))
-#endif
 PNG_FIXED_EXPORT(213, void, png_set_sCAL_fixed, (png_const_structrp png_ptr,
    png_inforp info_ptr, int unit, png_fixed_point width,
    png_fixed_point height))
@@ -2376,7 +2379,7 @@ PNG_EXPORT(171, void, png_set_sCAL_s, (png_const_structrp png_ptr,
  * READ:
  *    PNG_HANDLE_CHUNK_AS_DEFAULT:
  *       Known chunks: do normal libpng processing, do not keep the chunk (but
- *          set the comments below about PNG_HANDLE_AS_UNKNOWN_SUPPORTED)
+ *          see the comments below about PNG_HANDLE_AS_UNKNOWN_SUPPORTED)
  *       Unknown chunks: for a specific chunk use the global default, when used
  *          as the default discard the chunk data.
  *    PNG_HANDLE_CHUNK_NEVER:
@@ -2392,12 +2395,21 @@ PNG_EXPORT(171, void, png_set_sCAL_s, (png_const_structrp png_ptr,
  * to specifying "NEVER", however when "AS_DEFAULT" is used for specific chunks
  * it simply resets the behavior to the libpng default.
  *
+ * INTERACTION WTIH USER CHUNK CALLBACKS:
  * The per-chunk handling is always used when there is a png_user_chunk_ptr
  * callback and the callback returns 0; the chunk is then always stored *unless*
  * it is critical and the per-chunk setting is other than ALWAYS.  Notice that
  * the global default is *not* used in this case.  (In effect the per-chunk
  * value is incremented to at least IF_SAFE.)
  *
+ * IMPORTANT NOTE: this behavior will change in libpng 1.7 - the global and
+ * per-chunk defaults will be honored.  If you want to preserve the current
+ * behavior when your callback returns 0 you must set PNG_HANDLE_CHUNK_IF_SAFE
+ * as the default - if you don't do this libpng 1.6 will issue a warning.
+ *
+ * If you want unhandled unknown chunks to be discarded in libpng 1.6 and
+ * earlier simply return '1' (handled).
+ *
  * PNG_HANDLE_AS_UNKNOWN_SUPPORTED:
  *    If this is *not* set known chunks will always be handled by libpng and
  *    will never be stored in the unknown chunk list.  Known chunks listed to
@@ -3092,6 +3104,24 @@ typedef struct
     * slight speed gain.
     */
 
+#define PNG_IMAGE_FLAG_16BIT_sRGB 0x04
+   /* On read if the image is a 16-bit per component image and there is no gAMA
+    * or sRGB chunk assume that the components are sRGB encoded.  Notice that
+    * images output by the simplified API always have gamma information; setting
+    * this flag only affects the interpretation of 16-bit images from an
+    * external source.  It is recommended that the application expose this flag
+    * to the user; the user can normally easily recognize the difference between
+    * linear and sRGB encoding.  This flag has no effect on write - the data
+    * passed to the write APIs must have the correct encoding (as defined
+    * above.)
+    *
+    * If the flag is not set (the default) input 16-bit per component data is
+    * assumed to be linear.
+    *
+    * NOTE: the flag can only be set after the png_image_begin_read_ call,
+    * because that call initializes the 'flags' field.
+    */
+
 #ifdef PNG_SIMPLIFIED_READ_SUPPORTED
 /* READ APIs
  * ---------
@@ -3142,7 +3172,7 @@ PNG_EXPORT(237, int, png_image_finish_read, (png_imagep image,
     *    PNG_FORMAT_FLAG_LINEAR *not* set.
     *
     * For linear output removing the alpha channel is always done by compositing
-    * on black and background is ignored.:
+    * on black and background is ignored.
     *
     * colormap must be supplied when PNG_FORMAT_FLAG_COLORMAP is set.  It must
     * be at least the size (in bytes) returned by PNG_IMAGE_COLORMAP_SIZE.
@@ -3204,14 +3234,59 @@ PNG_EXPORT(240, int, png_image_write_to_stdio, (png_imagep image, FILE *file,
  *  END OF SIMPLIFIED API
  ******************************************************************************/
 
-#if defined(PNG_READ_CHECK_FOR_INVALID_INDEX_SUPPORTED) || \
-    defined(PNG_WRITE_CHECK_FOR_INVALID_INDEX_SUPPORTED)
+#ifdef PNG_CHECK_FOR_INVALID_INDEX_SUPPORTED
 PNG_EXPORT(242, void, png_set_check_for_invalid_index,
     (png_structrp png_ptr, int allowed));
+#  ifdef PNG_GET_PALETTE_MAX_SUPPORTED
+PNG_EXPORT(243, int, png_get_palette_max, (png_const_structp png_ptr,
+    png_const_infop info_ptr));
+#  endif
+#endif /* CHECK_FOR_INVALID_INDEX */
+
+/*******************************************************************************
+ *  IMPLEMENTATION OPTIONS
+ *******************************************************************************
+ *
+ * Support for arbitrary implementation-specific optimizations.  The API allows
+ * particular options to be turned on or off.  'Option' is the number of the
+ * option and 'onoff' is 0 (off) or non-0 (on).  The value returned is given
+ * by the PNG_OPTION_ defines below.
+ *
+ * HARDWARE: normally hardware capabilites, such as the Intel SSE instructions,
+ *           are detected at run time, however sometimes it may be impossible
+ *           to do this in user mode, in which case it is necessary to discover
+ *           the capabilities in an OS specific way.  Such capabilities are
+ *           listed here when libpng has support for them and must be turned
+ *           ON by the application if present.
+ *
+ * SOFTWARE: sometimes software optimizations actually result in performance
+ *           decrease on some architectures or systems, or with some sets of
+ *           PNG images.  'Software' options allow such optimizations to be
+ *           selected at run time.
+ */
+#ifdef PNG_SET_OPTION_SUPPORTED
+#ifdef PNG_ARM_NEON_API_SUPPORTED
+#  define PNG_ARM_NEON   0 /* HARDWARE: ARM Neon SIMD instructions supported */
+#endif
+#define PNG_MAXIMUM_INFLATE_WINDOW 2 /* SOFTWARE: force maximum window */
+#define PNG_OPTION_NEXT  4 /* Next option - numbers must be even */
+
+/* Return values: NOTE: there are four values and 'off' is *not* zero */
+#define PNG_OPTION_UNSET   0 /* Unset - defaults to off */
+#define PNG_OPTION_INVALID 1 /* Option number out of range */
+#define PNG_OPTION_OFF     2
+#define PNG_OPTION_ON      3
+
+PNG_EXPORT(244, int, png_set_option, (png_structrp png_ptr, int option,
+   int onoff));
 #endif
 
+/*******************************************************************************
+ *  END OF HARDWARE OPTIONS
+ ******************************************************************************/
+
 /* Maintainer: Put new public prototypes here ^, in libpng.3, and project
- * defs
+ * defs, scripts/pnglibconf.h, and scripts/pnglibconf.h.prebuilt
  */
 
 /* The last ordinal number (this is the *last* one already used; the next
@@ -3219,7 +3294,7 @@ PNG_EXPORT(242, void, png_set_check_for_invalid_index,
  * scripts/symbols.def as well.
  */
 #ifdef PNG_EXPORT_LAST_ORDINAL
-  PNG_EXPORT_LAST_ORDINAL(242);
+  PNG_EXPORT_LAST_ORDINAL(244);
 #endif
 
 #ifdef __cplusplus

pngconf.h

@@ -1,7 +1,7 @@
 
 /* pngconf.h - machine configurable file for libpng
  *
- * libpng version 1.7.0alpha09 - January 21, 2013
+ * libpng version 1.6.3beta06 - May 12, 2013
  *
  * Copyright (c) 1998-2013 Glenn Randers-Pehrson
  * (Version 0.96 Copyright (c) 1996, 1997 Andreas Dilger)
@@ -218,7 +218,7 @@
 #    define PNGCAPI __watcall
 #  endif
 
-#  if defined(__GNUC__) || (defined (_MSC_VER) && (_MSC_VER >= 800))
+#  if defined(__GNUC__) || (defined(_MSC_VER) && (_MSC_VER >= 800))
 #    define PNGCAPI __cdecl
 #    if PNG_API_RULE == 1
        /* If this line results in an error __stdcall is not understood and

pngerror.c

@@ -1,7 +1,7 @@
 
 /* pngerror.c - stub functions for i/o and memory allocation
  *
- * Last changed in libpng 1.7.0 [(PENDING RELEASE)]
+ * Last changed in libpng 1.6.1 [March 28, 2013]
  * Copyright (c) 1998-2013 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.)
@@ -163,7 +163,7 @@ png_format_number(png_const_charp start, png_charp end, int format,
          case PNG_NUMBER_FORMAT_02u:
             /* Expects at least 2 digits. */
             mincount = 2;
-            /* fall through */
+            /* FALL THROUGH */
 
          case PNG_NUMBER_FORMAT_u:
             *--end = digits[number % 10];
@@ -173,7 +173,7 @@ png_format_number(png_const_charp start, png_charp end, int format,
          case PNG_NUMBER_FORMAT_02x:
             /* This format expects at least two digits */
             mincount = 2;
-            /* fall through */
+            /* FALL THROUGH */
 
          case PNG_NUMBER_FORMAT_x:
             *--end = digits[number & 0xf];
@@ -516,7 +516,7 @@ png_chunk_report(png_const_structrp png_ptr, png_const_charp message, int error)
    /* This is always supported, but for just read or just write it
     * unconditionally does the right thing.
     */
-#  if (defined PNG_READ_SUPPORTED) && (defined PNG_WRITE_SUPPORTED)
+#  if defined(PNG_READ_SUPPORTED) && defined(PNG_WRITE_SUPPORTED)
       if (png_ptr->mode & PNG_IS_READ_STRUCT)
 #  endif
 
@@ -530,7 +530,7 @@ png_chunk_report(png_const_structrp png_ptr, png_const_charp message, int error)
       }
 #  endif
 
-#  if (defined PNG_READ_SUPPORTED) && (defined PNG_WRITE_SUPPORTED)
+#  if defined(PNG_READ_SUPPORTED) && defined(PNG_WRITE_SUPPORTED)
       else if (!(png_ptr->mode & PNG_IS_READ_STRUCT))
 #  endif
 
@@ -546,13 +546,7 @@ png_chunk_report(png_const_structrp png_ptr, png_const_charp message, int error)
 }
 
 #ifdef PNG_ERROR_TEXT_SUPPORTED
-
-#if defined(PNG_FLOATING_POINT_SUPPORTED) && \
-   (defined(PNG_gAMA_SUPPORTED) || defined(PNG_cHRM_SUPPORTED) || \
-   defined(PNG_sCAL_SUPPORTED) || defined(PNG_READ_BACKGROUND_SUPPORTED) || \
-   defined(PNG_READ_RGB_TO_GRAY_SUPPORTED)) || \
-   (defined(PNG_FLOATING_ARITHMETIC_SUPPORTED) &&\
-   defined(PNG_sCAL_SUPPORTED))
+#ifdef PNG_FLOATING_POINT_SUPPORTED
 PNG_FUNCTION(void,
 png_fixed_error,(png_const_structrp png_ptr, png_const_charp name),PNG_NORETURN)
 {
@@ -746,17 +740,8 @@ png_longjmp,(png_const_structrp png_ptr, int val),PNG_NORETURN)
       png_ptr->longjmp_fn(*png_ptr->jmp_buf_ptr, val);
 #endif
 
-   /* If control reaches this point, png_longjmp() must not return. The only
-    * choice is to terminate the whole process (or maybe the thread); to do
-    * this the ANSI-C abort() function is used unless a different method is 
-    * implemented by overriding the default configuration setting for
-    * PNG_ABORT (see scripts/pnglibconf.dfa).
-    *
-    * API change: prior to 1.7.0 PNG_ABORT was invoked as a function type macro
-    * with no arguments 'PNG_ABORT();', in 1.7.0 this is changed to a simple
-    * macro that is defined in the configuration.
-    */
-   PNG_ABORT
+   /* Here if not setjmp support or if png_ptr is null. */
+   PNG_ABORT();
 }
 
 #ifdef PNG_WARNINGS_SUPPORTED
@@ -859,8 +844,8 @@ png_set_strip_error_numbers(png_structrp png_ptr, png_uint_32 strip_mode)
 }
 #endif
 
-#if defined PNG_SIMPLIFIED_READ_SUPPORTED ||\
-   defined PNG_SIMPLIFIED_WRITE_SUPPORTED
+#if defined(PNG_SIMPLIFIED_READ_SUPPORTED) ||\
+   defined(PNG_SIMPLIFIED_WRITE_SUPPORTED)
    /* Currently the above both depend on SETJMP_SUPPORTED, however it would be
     * possible to implement without setjmp support just so long as there is some
     * way to handle the error return here:

pngget.c

@@ -1,7 +1,7 @@
 
 /* pngget.c - retrieval of values from info struct
  *
- * Last changed in libpng 1.7.0 [(PENDING RELEASE)]
+ * Last changed in libpng 1.6.1 [March 28, 2013]
  * Copyright (c) 1998-2013 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.)
@@ -552,14 +552,14 @@ png_get_cHRM_XYZ(png_const_structrp png_ptr, png_const_inforp info_ptr,
          *green_Z = png_float(png_ptr,
             info_ptr->colorspace.end_points_XYZ.green_Z, "cHRM green Z");
       if (blue_X != NULL)
-         *blue_X = png_float(png_ptr, info_ptr->colorspace.end_points_XYZ.blue_X,
-            "cHRM blue X");
+         *blue_X = png_float(png_ptr,
+            info_ptr->colorspace.end_points_XYZ.blue_X, "cHRM blue X");
       if (blue_Y != NULL)
-         *blue_Y = png_float(png_ptr, info_ptr->colorspace.end_points_XYZ.blue_Y,
-            "cHRM blue Y");
+         *blue_Y = png_float(png_ptr,
+            info_ptr->colorspace.end_points_XYZ.blue_Y, "cHRM blue Y");
       if (blue_Z != NULL)
-         *blue_Z = png_float(png_ptr, info_ptr->colorspace.end_points_XYZ.blue_Z,
-            "cHRM blue Z");
+         *blue_Z = png_float(png_ptr,
+            info_ptr->colorspace.end_points_XYZ.blue_Z, "cHRM blue Z");
       return (PNG_INFO_cHRM);
    }
 
@@ -843,8 +843,9 @@ png_get_pCAL(png_const_structrp png_ptr, png_inforp info_ptr,
 #endif
 
 #ifdef PNG_sCAL_SUPPORTED
-#  ifdef PNG_FLOATING_ARITHMETIC_SUPPORTED
-#     ifdef PNG_FIXED_POINT_SUPPORTED
+#  ifdef PNG_FIXED_POINT_SUPPORTED
+#    if defined(PNG_FLOATING_ARITHMETIC_SUPPORTED) || \
+         defined(PNG_FLOATING_POINT_SUPPORTED)
 png_uint_32 PNGAPI
 png_get_sCAL_fixed(png_const_structrp png_ptr, png_const_inforp info_ptr,
     int *unit, png_fixed_point *width, png_fixed_point *height)
@@ -865,8 +866,9 @@ png_get_sCAL_fixed(png_const_structrp png_ptr, png_const_inforp info_ptr,
 
    return(0);
 }
-#     endif /* FIXED_POINT */
-#     ifdef PNG_FLOATING_POINT_SUPPORTED
+#    endif /* FLOATING_ARITHMETIC */
+#  endif /* FIXED_POINT */
+#  ifdef PNG_FLOATING_POINT_SUPPORTED
 png_uint_32 PNGAPI
 png_get_sCAL(png_const_structrp png_ptr, png_const_inforp info_ptr,
     int *unit, double *width, double *height)
@@ -882,9 +884,7 @@ png_get_sCAL(png_const_structrp png_ptr, png_const_inforp info_ptr,
 
    return(0);
 }
-#     endif /* FLOATING POINT */
-#  endif /* FLOATING_ARITHMETIC */
-
+#  endif /* FLOATING POINT */
 png_uint_32 PNGAPI
 png_get_sCAL_s(png_const_structrp png_ptr, png_const_inforp info_ptr,
     int *unit, png_charpp width, png_charpp height)
@@ -1161,4 +1161,17 @@ png_get_io_chunk_type (png_const_structrp png_ptr)
 }
 #endif /* ?PNG_IO_STATE_SUPPORTED */
 
+#ifdef PNG_CHECK_FOR_INVALID_INDEX_SUPPORTED
+#  ifdef PNG_GET_PALETTE_MAX_SUPPORTED
+int PNGAPI
+png_get_palette_max(png_const_structp png_ptr, png_const_infop info_ptr)
+{
+   if (png_ptr != NULL && info_ptr != NULL)
+      return png_ptr->num_palette_max;
+
+   return (-1);
+}
+#  endif
+#endif
+
 #endif /* PNG_READ_SUPPORTED || PNG_WRITE_SUPPORTED */

pnginfo.h

@@ -1,11 +1,11 @@
 
 /* pnginfo.h - header file for PNG reference library
  *
- * Copyright (c) 1998-2011 Glenn Randers-Pehrson
+ * Copyright (c) 1998-2013 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.)
  *
- * Last changed in libpng 1.5.0 [January 6, 2011]
+ * Last changed in libpng 1.6.1 [March 28, 2013]
  *
  * This code is released under the libpng license.
  * For conditions of distribution and use, see the disclaimer
@@ -88,7 +88,7 @@ struct png_info_def
     * and initialize the appropriate fields below.
     */
 
-#if defined PNG_COLORSPACE_SUPPORTED || defined PNG_GAMMA_SUPPORTED
+#if defined(PNG_COLORSPACE_SUPPORTED) || defined(PNG_GAMMA_SUPPORTED)
    /* png_colorspace only contains 'flags' if neither GAMMA or COLORSPACE are
     * defined.  When COLORSPACE is switched on all the colorspace-defining
     * chunks should be enabled, when GAMMA is switched on all the gamma-defining
@@ -223,13 +223,17 @@ defined(PNG_READ_BACKGROUND_SUPPORTED)
 #ifdef PNG_STORE_UNKNOWN_CHUNKS_SUPPORTED
    /* Storage for unknown chunks that the library doesn't recognize. */
    png_unknown_chunkp unknown_chunks;
+
+   /* The type of this field is limited by the type of 
+    * png_struct::user_chunk_cache_max, else overflow can occur.
+    */
    int                unknown_chunks_num;
 #endif
 
 #ifdef PNG_sPLT_SUPPORTED
    /* Data on sPLT chunks (there may be more than one). */
    png_sPLT_tp splt_palettes;
-   int         splt_palettes_num;
+   int         splt_palettes_num; /* Match type returned by png_get API */
 #endif
 
 #ifdef PNG_sCAL_SUPPORTED

pngmem.c

@@ -1,7 +1,7 @@
 
 /* pngmem.c - stub functions for memory allocation
  *
- * Last changed in libpng 1.7.0 [(PENDING RELEASE)]
+ * Last changed in libpng 1.6.0 [February 14, 2013]
  * Copyright (c) 1998-2013 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.)
@@ -172,11 +172,31 @@ png_malloc,(png_const_structrp png_ptr, png_alloc_size_t size),PNG_ALLOCATED)
    ret = png_malloc_base(png_ptr, size);
 
    if (ret == NULL)
-       png_error(png_ptr, "Out of memory");
+       png_error(png_ptr, "Out of memory"); /* 'm' means png_malloc */
 
    return ret;
 }
 
+#ifdef PNG_USER_MEM_SUPPORTED
+PNG_FUNCTION(png_voidp,PNGAPI
+png_malloc_default,(png_const_structrp png_ptr, png_alloc_size_t size),
+   PNG_ALLOCATED PNG_DEPRECATED)
+{
+   png_voidp ret;
+
+   if (png_ptr == NULL)
+      return NULL;
+
+   /* Passing 'NULL' here bypasses the application provided memory handler. */
+   ret = png_malloc_base(NULL/*use malloc*/, size);
+
+   if (ret == NULL)
+      png_error(png_ptr, "Out of Memory"); /* 'M' means png_malloc_default */
+
+   return ret;
+}
+#endif /* PNG_USER_MEM_SUPPORTED */
+
 /* This function was added at libpng version 1.2.3.  The png_malloc_warn()
  * function will issue a png_warning and return NULL instead of issuing a
  * png_error, if it fails to allocate the requested memory.
@@ -212,8 +232,17 @@ png_free(png_const_structrp png_ptr, png_voidp ptr)
       png_ptr->free_fn(png_constcast(png_structrp,png_ptr), ptr);
 
    else
+      png_free_default(png_ptr, ptr);
+}
+
+PNG_FUNCTION(void,PNGAPI
+png_free_default,(png_const_structrp png_ptr, png_voidp ptr),PNG_DEPRECATED)
+{
+   if (png_ptr == NULL || ptr == NULL)
+      return;
 #endif /* PNG_USER_MEM_SUPPORTED */
-      free(ptr);
+
+   free(ptr);
 }
 
 #ifdef PNG_USER_MEM_SUPPORTED

pngpread.c

@@ -1,7 +1,7 @@
 
 /* pngpread.c - read a png file in push mode
  *
- * Last changed in libpng 1.7.0 [(PENDING RELEASE)]
+ * Last changed in libpng 1.6.0 [February 14, 2013]
  * Copyright (c) 1998-2013 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.)

pngpriv.h

@@ -6,7 +6,7 @@
  * (Version 0.96 Copyright (c) 1996, 1997 Andreas Dilger)
  * (Version 0.88 Copyright (c) 1995, 1996 Guy Eric Schalnat, Group 42, Inc.)
  *
- * Last changed in libpng 1.7.0 [(PENDING RELEASE)]
+ * Last changed in libpng 1.6.2 [April 25, 2013]
  *
  * This code is released under the libpng license.
  * For conditions of distribution and use, see the disclaimer
@@ -39,9 +39,11 @@
  */
 #define _POSIX_SOURCE 1 /* Just the POSIX 1003.1 and C89 APIs */
 
+#ifndef PNG_VERSION_INFO_ONLY
 /* Standard library headers not required by png.h: */
-#include <stdlib.h>
-#include <string.h>
+#  include <stdlib.h>
+#  include <string.h>
+#endif
 
 #define PNGLIB_BUILD /*libpng is being built, not used*/
 
@@ -54,7 +56,7 @@
  * configure generated config.h.  Libpng is expected to compile without *any*
  * special build system support on a reasonably ANSI-C compliant system.
  */
-#if (defined HAVE_CONFIG_H) && !(defined PNG_NO_CONFIG_H)
+#if defined(HAVE_CONFIG_H) && !defined(PNG_NO_CONFIG_H)
 #  include <config.h>
 
    /* Pick up the definition of 'restrict' from config.h if it was read: */
@@ -71,7 +73,7 @@
 #endif
 
 /* Local renames may change non-exported API functions from png.h */
-#if defined PNG_PREFIX && !defined PNGPREFIX_H
+#if defined(PNG_PREFIX) && !defined(PNGPREFIX_H)
 #  include "pngprefix.h"
 #endif
 
@@ -177,10 +179,12 @@
 #  ifndef PNG_FLOATING_POINT_SUPPORTED
 #     define PNG_FP_EXPORT(ordinal, type, name, args)\
          PNG_INTERNAL_FUNCTION(type, name, args, PNG_EMPTY);
-      typedef struct png_incomplete png_double;
-      typedef png_double*           png_doublep;
-      typedef const png_double*     png_const_doublep;
-      typedef png_double**          png_doublepp;
+#     ifndef PNG_VERSION_INFO_ONLY
+         typedef struct png_incomplete png_double;
+         typedef png_double*           png_doublep;
+         typedef const png_double*     png_const_doublep;
+         typedef png_double**          png_doublepp;
+#     endif
 #  endif
 #endif
 #ifndef PNG_FIXED_EXPORT
@@ -191,8 +195,6 @@
 #endif
 
 #include "png.h"
-#include "pngstruct.h"
-#include "pnginfo.h"
 
 /* pngconf.h does not set PNG_DLL_EXPORT unless it is required, so: */
 #ifndef PNG_DLL_EXPORT
@@ -238,11 +240,6 @@
 #  endif
 #endif
 
-/* This is used for 16 bit gamma tables -- only the top level pointers are
- * const; this could be changed:
- */
-typedef const png_uint_16p * png_const_uint_16pp;
-
 /* Moved to pngpriv.h at libpng-1.5.0 */
 /* NOTE: some of these may have been used in external applications as
  * these definitions were exposed in pngconf.h prior to 1.5.
@@ -331,28 +328,21 @@ typedef const png_uint_16p * png_const_uint_16pp;
 #  define PNGFAPI /* PRIVATE */
 #endif
 
+#ifndef PNG_VERSION_INFO_ONLY
 /* Other defines specific to compilers can go here.  Try to keep
  * them inside an appropriate ifdef/endif pair for portability.
  */
-#if defined PNG_sCAL_SUPPORTED && defined PNG_FLOATING_POINT_SUPPORTED
+#if defined(PNG_FLOATING_POINT_SUPPORTED) ||\
+    defined(PNG_FLOATING_ARITHMETIC_SUPPORTED)
    /* png.c requires the following ANSI-C constants if the conversion of
     * floating point to ASCII is implemented therein:
     *
-    *  DBL_MIN_10_EXP Minimum negative integer such that 10^integer is a
-    *                 normalized (double) value.
     *  DBL_DIG  Maximum number of decimal digits (can be set to any constant)
     *  DBL_MIN  Smallest normalized fp number (can be set to an arbitrary value)
     *  DBL_MAX  Maximum floating point number (can be set to an arbitrary value)
     */
 #  include <float.h>
-#endif /* sCAL && FLOATING_POINT */
 
-#if defined PNG_FLOATING_ARITHMETIC_SUPPORTED ||\
-   defined PNG_FLOATING_POINT_SUPPORTED
-   /* Certain floating point functions are used internally; only floor and ceil
-    * if FLOATING_POINT is supported, but if FLOATING_ARITHMETIC is used then
-    * pow and exp are needed too.
-    */
 #  if (defined(__MWERKS__) && defined(macintosh)) || defined(applec) || \
     defined(THINK_C) || defined(__SC__) || defined(TARGET_OS_MAC)
      /* We need to check that <math.h> hasn't already been included earlier
@@ -371,7 +361,33 @@ typedef const png_uint_16p * png_const_uint_16pp;
       */
 #    include <m68881.h>
 #  endif
-#endif /* FLOATING_ARITHMETIC || FLOATING_POINT */
+#endif
+
+/* This provides the non-ANSI (far) memory allocation routines. */
+#if defined(__TURBOC__) && defined(__MSDOS__)
+#  include <mem.h>
+#  include <alloc.h>
+#endif
+
+#if defined(WIN32) || defined(_Windows) || defined(_WINDOWS) || \
+    defined(_WIN32) || defined(__WIN32__)
+#  include <windows.h>  /* defines _WINDOWS_ macro */
+#endif
+#endif /* PNG_VERSION_INFO_ONLY */
+
+/* Moved here around 1.5.0beta36 from pngconf.h */
+/* Users may want to use these so they are not private.  Any library
+ * functions that are passed far data must be model-independent.
+ */
+
+/* Memory model/platform independent fns */
+#ifndef PNG_ABORT
+#  ifdef _WINDOWS_
+#    define PNG_ABORT() ExitProcess(0)
+#  else
+#    define PNG_ABORT() abort()
+#  endif
+#endif
 
 /* These macros may need to be architecture dependent. */
 #define PNG_ALIGN_NONE   0 /* do not use data alignment */
@@ -441,7 +457,7 @@ typedef const png_uint_16p * png_const_uint_16pp;
 #define PNG_HAVE_CHUNK_HEADER      0x100
 #define PNG_WROTE_tIME             0x200
 #define PNG_WROTE_INFO_BEFORE_PLTE 0x400
-                   /*              0x800 (unused) */
+#define PNG_BACKGROUND_IS_GRAY     0x800
 #define PNG_HAVE_PNG_SIGNATURE    0x1000
 #define PNG_HAVE_CHUNK_AFTER_IDAT 0x2000 /* Have another chunk after IDAT */
                    /*             0x4000 (unused) */
@@ -455,10 +471,10 @@ typedef const png_uint_16p * png_const_uint_16pp;
 #define PNG_SWAP_BYTES          0x0010
 #define PNG_INVERT_MONO         0x0020
 #define PNG_QUANTIZE            0x0040
-#define PNG_COMPOSE             0x0080 /* Was PNG_BACKGROUND */
-                       /*       0x0100 unused */
-#define PNG_EXPAND_16           0x0200 /* Added to libpng 1.5.2 */
-#define PNG_16_TO_8             0x0400 /* Becomes 'chop' in 1.5.4 */
+#define PNG_COMPOSE             0x0080     /* Was PNG_BACKGROUND */
+#define PNG_BACKGROUND_EXPAND   0x0100
+#define PNG_EXPAND_16           0x0200     /* Added to libpng 1.5.2 */
+#define PNG_16_TO_8             0x0400     /* Becomes 'chop' in 1.5.4 */
 #define PNG_RGBA                0x0800
 #define PNG_EXPAND              0x1000
 #define PNG_GAMMA               0x2000
@@ -473,13 +489,13 @@ typedef const png_uint_16p * png_const_uint_16pp;
 #define PNG_RGB_TO_GRAY_WARN  0x400000
 #define PNG_RGB_TO_GRAY       0x600000 /* two bits, RGB_TO_GRAY_ERR|WARN */
 #define PNG_ENCODE_ALPHA      0x800000 /* Added to libpng-1.5.4 */
-#define PNG_ADD_ALPHA        0x1000000 /* Added to libpng-1.2.7 */
-#define PNG_EXPAND_tRNS      0x2000000 /* Added to libpng-1.2.9 */
-#define PNG_SCALE_16_TO_8    0x4000000 /* Added to libpng-1.5.4 */
-                       /*    0x8000000 unused */
-                       /*   0x10000000 unused */
-                       /*   0x20000000 unused */
-                       /*   0x40000000 unused */
+#define PNG_ADD_ALPHA         0x1000000 /* Added to libpng-1.2.7 */
+#define PNG_EXPAND_tRNS       0x2000000 /* Added to libpng-1.2.9 */
+#define PNG_SCALE_16_TO_8     0x4000000 /* Added to libpng-1.5.4 */
+                       /*   0x8000000 unused */
+                       /*  0x10000000 unused */
+                       /*  0x20000000 unused */
+                       /*  0x40000000 unused */
 /* Flags for png_create_struct */
 #define PNG_STRUCT_PNG   0x0001
 #define PNG_STRUCT_INFO  0x0002
@@ -512,8 +528,8 @@ typedef const png_uint_16p * png_const_uint_16pp;
 #define PNG_FLAG_BENIGN_ERRORS_WARN     0x100000 /* Added to libpng-1.4.0 */
 #define PNG_FLAG_APP_WARNINGS_WARN      0x200000 /* Added to libpng-1.6.0 */
 #define PNG_FLAG_APP_ERRORS_WARN        0x400000 /* Added to libpng-1.6.0 */
-#define PNG_FLAG_BACKGROUND_IS_GRAY     0x800000
-#define PNG_FLAG_BACKGROUND_EXPAND     0x1000000
+                                  /*    0x800000    unused */
+                                  /*   0x1000000    unused */
                                   /*   0x2000000    unused */
                                   /*   0x4000000    unused */
                                   /*   0x8000000    unused */
@@ -536,26 +552,6 @@ typedef const png_uint_16p * png_const_uint_16pp;
    abs((int)((c1).green) - (int)((c2).green)) + \
    abs((int)((c1).blue) - (int)((c2).blue)))
 
-/* Added to libpng-1.5.7: sRGB conversion tables */
-#if defined PNG_SIMPLIFIED_READ_SUPPORTED ||\
-   defined PNG_SIMPLIFIED_WRITE_SUPPORTED
-#ifdef PNG_SIMPLIFIED_READ_SUPPORTED
-PNG_INTERNAL_DATA(const png_uint_16, png_sRGB_table, [256]);
-   /* Convert from an sRGB encoded value 0..255 to a 16-bit linear value,
-    * 0..65535.  This table gives the closest 16-bit answers (no errors).
-    */
-#endif
-
-PNG_INTERNAL_DATA(const png_uint_16, png_sRGB_base, [512]);
-PNG_INTERNAL_DATA(const png_byte, png_sRGB_delta, [512]);
-
-#define PNG_sRGB_FROM_LINEAR(linear) ((png_byte)((png_sRGB_base[(linear)>>15] +\
-   ((((linear)&0x7fff)*png_sRGB_delta[(linear)>>15])>>12)) >> 8))
-   /* Given a value 'linear' in the range 0..255*65535 calculate the 8-bit sRGB
-    * encoded value with maximum error 0.646365.  Note that the input is not a
-    * 16-bit value; it has been multiplied by 255! */
-#endif /* PNG_SIMPLIFIED_READ/WRITE */
-
 /* Added to libpng-1.6.0: scale a 16-bit value in the range 0..65535 to 0..255
  * by dividing by 257 *with rounding*.  This macro is exact for the given range.
  * See the discourse in pngrtran.c png_do_scale_16_to_8.  The values in the
@@ -679,8 +675,8 @@ PNG_INTERNAL_DATA(const png_byte, png_sRGB_delta, [512]);
    (void)(PNG_STRING_FROM_CHUNK(s,c), ((char*)(s))[4] = 0)
 
 /* Test on flag values as defined in the spec (section 5.4): */
-#define PNG_CHUNK_ANCILLIARY(c)   (1 & ((c) >> 29))
-#define PNG_CHUNK_CRITICAL(c)     (!PNG_CHUNK_ANCILLIARY(c))
+#define PNG_CHUNK_ANCILLARY(c)   (1 & ((c) >> 29))
+#define PNG_CHUNK_CRITICAL(c)     (!PNG_CHUNK_ANCILLARY(c))
 #define PNG_CHUNK_PRIVATE(c)      (1 & ((c) >> 21))
 #define PNG_CHUNK_RESERVED(c)     (1 & ((c) >> 13))
 #define PNG_CHUNK_SAFE_TO_COPY(c) (1 & ((c) >>  5))
@@ -690,6 +686,57 @@ PNG_INTERNAL_DATA(const png_byte, png_sRGB_delta, [512]);
 #define PNG_GAMMA_MAC_INVERSE 65909
 #define PNG_GAMMA_sRGB_INVERSE 45455
 
+/* Almost everything below is C specific; the #defines above can be used in
+ * non-C code (so long as it is C-preprocessed) the rest of this stuff cannot.
+ */
+#ifndef PNG_VERSION_INFO_ONLY
+
+#include "pngstruct.h"
+#include "pnginfo.h"
+
+/* Validate the include paths - the include path used to generate pnglibconf.h
+ * must match that used in the build, or we must be using pnglibconf.h.prebuilt:
+ */
+#if PNG_ZLIB_VERNUM != 0 && PNG_ZLIB_VERNUM != ZLIB_VERNUM
+#  error ZLIB_VERNUM != PNG_ZLIB_VERNUM \
+      "-I (include path) error: see the notes in pngpriv.h"
+   /* This means that when pnglibconf.h was built the copy of zlib.h that it
+    * used is not the same as the one being used here.  Because the build of
+    * libpng makes decisions to use inflateInit2 and inflateReset2 based on the
+    * zlib version number and because this affects handling of certain broken
+    * PNG files the -I directives must match.
+    *
+    * The most likely explanation is that you passed a -I in CFLAGS, this will
+    * not work; all the preprocessor directories and in particular all the -I
+    * directives must be in CPPFLAGS.
+    */
+#endif
+
+/* This is used for 16 bit gamma tables -- only the top level pointers are
+ * const; this could be changed:
+ */
+typedef const png_uint_16p * png_const_uint_16pp;
+
+/* Added to libpng-1.5.7: sRGB conversion tables */
+#if defined(PNG_SIMPLIFIED_READ_SUPPORTED) ||\
+   defined(PNG_SIMPLIFIED_WRITE_SUPPORTED)
+#ifdef PNG_SIMPLIFIED_READ_SUPPORTED
+PNG_INTERNAL_DATA(const png_uint_16, png_sRGB_table, [256]);
+   /* Convert from an sRGB encoded value 0..255 to a 16-bit linear value,
+    * 0..65535.  This table gives the closest 16-bit answers (no errors).
+    */
+#endif
+
+PNG_INTERNAL_DATA(const png_uint_16, png_sRGB_base, [512]);
+PNG_INTERNAL_DATA(const png_byte, png_sRGB_delta, [512]);
+
+#define PNG_sRGB_FROM_LINEAR(linear) ((png_byte)((png_sRGB_base[(linear)>>15] +\
+   ((((linear)&0x7fff)*png_sRGB_delta[(linear)>>15])>>12)) >> 8))
+   /* Given a value 'linear' in the range 0..255*65535 calculate the 8-bit sRGB
+    * encoded value with maximum error 0.646365.  Note that the input is not a
+    * 16-bit value; it has been multiplied by 255! */
+#endif /* PNG_SIMPLIFIED_READ/WRITE */
+
 
 /* Inhibit C++ name-mangling for libpng functions but not for system calls. */
 #ifdef __cplusplus
@@ -716,16 +763,6 @@ PNG_INTERNAL_FUNCTION(void,png_free_buffer_list,(png_structrp png_ptr,
    /* Free the buffer list used by the compressed write code. */
 #endif
 
-#ifdef PNG_WRITE_FILTER_SUPPORTED
-PNG_INTERNAL_FUNCTION(void,png_write_alloc_filter_row_buffers,
-   (png_structrp png_ptr, int filters),PNG_EMPTY);
-   /* Allocate pixel row buffers to cache filtered rows while testing candidate
-    * filters.
-    * TODO: avoid this, only one spare row buffer (at most) is required, this
-    * wastes a lot of memory for large images.
-    */
-#endif
-
 #if defined(PNG_FLOATING_POINT_SUPPORTED) && \
    !defined(PNG_FIXED_POINT_MACRO_SUPPORTED) && \
    (defined(PNG_gAMA_SUPPORTED) || defined(PNG_cHRM_SUPPORTED) || \
@@ -750,10 +787,10 @@ PNG_INTERNAL_FUNCTION(int,png_user_version_check,(png_structrp png_ptr,
 PNG_INTERNAL_FUNCTION(png_voidp,png_malloc_base,(png_const_structrp png_ptr,
    png_alloc_size_t size),PNG_ALLOCATED);
 
-#if defined PNG_TEXT_SUPPORTED || defined PNG_sPLT_SUPPORTED ||\
-   defined PNG_STORE_UNKNOWN_CHUNKS_SUPPORTED
+#if defined(PNG_TEXT_SUPPORTED) || defined(PNG_sPLT_SUPPORTED) ||\
+   defined(PNG_STORE_UNKNOWN_CHUNKS_SUPPORTED)
 /* Internal array allocator, outputs no error or warning messages on failure,
- * just returns NULL.
+ * just returns NULL.  
  */
 PNG_INTERNAL_FUNCTION(png_voidp,png_malloc_array,(png_const_structrp png_ptr,
    int nelements, size_t element_size),PNG_ALLOCATED);
@@ -1812,13 +1849,13 @@ PNG_INTERNAL_FUNCTION(png_byte,png_gamma_8bit_correct,(unsigned int value,
    png_fixed_point gamma_value),PNG_EMPTY);
 PNG_INTERNAL_FUNCTION(void,png_destroy_gamma_table,(png_structrp png_ptr),
    PNG_EMPTY);
-PNG_INTERNAL_FUNCTION(void,png_build_gamma_tables,(png_structrp png_ptr,
+PNG_INTERNAL_FUNCTION(void,png_build_gamma_table,(png_structrp png_ptr,
    int bit_depth),PNG_EMPTY);
 #endif
 
 /* SIMPLIFIED READ/WRITE SUPPORT */
-#if defined PNG_SIMPLIFIED_READ_SUPPORTED ||\
-   defined PNG_SIMPLIFIED_WRITE_SUPPORTED
+#if defined(PNG_SIMPLIFIED_READ_SUPPORTED) ||\
+   defined(PNG_SIMPLIFIED_WRITE_SUPPORTED)
 /* The internal structure that png_image::opaque points to. */
 typedef struct png_control
 {
@@ -1873,7 +1910,7 @@ PNG_INTERNAL_FUNCTION(void, png_image_free, (png_imagep image), PNG_EMPTY);
 #endif /* SIMPLIFIED READ/WRITE */
 
 #ifdef PNG_FILTER_OPTIMIZATIONS
-PNG_INTERNAL_FUNCTION(void, PNG_FILTER_OPTIMIZATIONS, (png_structrp png_ptr,
+PNG_INTERNAL_FUNCTION(void, PNG_FILTER_OPTIMIZATIONS, (png_structp png_ptr,
     unsigned int bpp), PNG_EMPTY);
    /* This is the initialization function for hardware specific optimizations,
     * one implementation (for ARM NEON machines) is contained in
@@ -1890,4 +1927,5 @@ PNG_INTERNAL_FUNCTION(void, PNG_FILTER_OPTIMIZATIONS, (png_structrp png_ptr,
 }
 #endif
 
+#endif /* PNG_VERSION_INFO_ONLY */
 #endif /* PNGPRIV_H */

pngread.c

@@ -1,7 +1,7 @@
 
 /* pngread.c - read a PNG file
  *
- * Last changed in libpng 1.7.0 [(PENDING RELEASE)]
+ * Last changed in libpng 1.6.1 [March 28, 2013]
  * Copyright (c) 1998-2013 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.)
@@ -15,7 +15,7 @@
  */
 
 #include "pngpriv.h"
-#if defined PNG_SIMPLIFIED_READ_SUPPORTED && defined PNG_STDIO_SUPPORTED
+#if defined(PNG_SIMPLIFIED_READ_SUPPORTED) && defined(PNG_STDIO_SUPPORTED)
 #  include <errno.h>
 #endif
 
@@ -877,8 +877,8 @@ png_read_destroy(png_structrp png_ptr)
    png_free(png_ptr, png_ptr->save_buffer);
 #endif
 
-#if (defined PNG_STORE_UNKNOWN_CHUNKS_SUPPORTED) &&\
-   (defined PNG_READ_UNKNOWN_CHUNKS_SUPPORTED)
+#if defined(PNG_STORE_UNKNOWN_CHUNKS_SUPPORTED) &&\
+   defined(PNG_READ_UNKNOWN_CHUNKS_SUPPORTED)
    png_free(png_ptr, png_ptr->unknown_chunk.data);
 #endif
 
@@ -2004,6 +2004,28 @@ png_image_read_colormap(png_voidp argument)
    else
       back_b = back_r = back_g = 255;
 
+   /* Default the input file gamma if required - this is necessary because
+    * libpng assumes that if no gamma information is present the data is in the
+    * output format, but the simplified API deduces the gamma from the input
+    * format.
+    */
+   if ((png_ptr->colorspace.flags & PNG_COLORSPACE_HAVE_GAMMA) == 0)
+   {
+      /* Do this directly, not using the png_colorspace functions, to ensure
+       * that it happens even if the colorspace is invalid (though probably if
+       * it is the setting will be ignored)  Note that the same thing can be
+       * achieved at the application interface with png_set_gAMA.
+       */
+      if (png_ptr->bit_depth == 16 &&
+         (image->flags & PNG_IMAGE_FLAG_16BIT_sRGB) == 0)
+         png_ptr->colorspace.gamma = PNG_GAMMA_LINEAR;
+
+      else
+         png_ptr->colorspace.gamma = PNG_GAMMA_sRGB_INVERSE;
+
+      png_ptr->colorspace.flags |= PNG_COLORSPACE_HAVE_GAMMA;
+   }
+
    /* Decide what to do based on the PNG color type of the input data.  The
     * utility function png_create_colormap_entry deals with most aspects of the
     * output transformations; this code works out how to produce bytes of
@@ -3547,7 +3569,8 @@ png_image_read_direct(png_voidp argument)
       {
          png_fixed_point input_gamma_default;
 
-         if (base_format & PNG_FORMAT_FLAG_LINEAR)
+         if ((base_format & PNG_FORMAT_FLAG_LINEAR) &&
+            (image->flags & PNG_IMAGE_FLAG_16BIT_sRGB) == 0)
             input_gamma_default = PNG_GAMMA_LINEAR;
          else
             input_gamma_default = PNG_DEFAULT_sRGB;

pngrio.c

@@ -1,7 +1,7 @@
 
 /* pngrio.c - functions for data input
  *
- * Last changed in libpng 1.7.0 [(PENDING RELEASE)]
+ * Last changed in libpng 1.6.0 [February 14, 2013]
  * Copyright (c) 1998-2013 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.)
@@ -102,7 +102,6 @@ png_set_read_fn(png_structrp png_ptr, png_voidp io_ptr,
    png_ptr->read_data_fn = read_data_fn;
 #endif
 
-#ifdef PNG_WRITE_SUPPORTED
    /* It is an error to write to a read device */
    if (png_ptr->write_data_fn != NULL)
    {
@@ -111,7 +110,6 @@ png_set_read_fn(png_structrp png_ptr, png_voidp io_ptr,
           "Can't set both read_data_fn and write_data_fn in the"
           " same structure");
    }
-#endif
 
 #ifdef PNG_WRITE_FLUSH_SUPPORTED
    png_ptr->output_flush_fn = NULL;

pngrutil.c

@@ -1,7 +1,7 @@
 
 /* pngrutil.c - utilities to read a PNG file
  *
- * Last changed in libpng 1.7.0 [(PENDING RELEASE)]
+ * Last changed in libpng 1.6.3 [(PENDING RELEASE)]
  * Copyright (c) 1998-2013 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.)
@@ -219,7 +219,7 @@ png_crc_finish(png_structrp png_ptr, png_uint_32 skip)
 
    if (png_crc_error(png_ptr))
    {
-      if (PNG_CHUNK_ANCILLIARY(png_ptr->chunk_name) ?
+      if (PNG_CHUNK_ANCILLARY(png_ptr->chunk_name) ?
           !(png_ptr->flags & PNG_FLAG_CRC_ANCILLARY_NOWARN) :
           (png_ptr->flags & PNG_FLAG_CRC_CRITICAL_USE))
       {
@@ -248,7 +248,7 @@ png_crc_error(png_structrp png_ptr)
    png_uint_32 crc;
    int need_crc = 1;
 
-   if (PNG_CHUNK_ANCILLIARY(png_ptr->chunk_name))
+   if (PNG_CHUNK_ANCILLARY(png_ptr->chunk_name))
    {
       if ((png_ptr->flags & PNG_FLAG_CRC_ANCILLARY_MASK) ==
           (PNG_FLAG_CRC_ANCILLARY_USE | PNG_FLAG_CRC_ANCILLARY_NOWARN))
@@ -332,7 +332,7 @@ png_read_buffer(png_structrp png_ptr, png_alloc_size_t new_size, int warn)
  * chunk apparently owns the stream.  Prior to release it does a png_error.
  */
 static int
-png_inflate_claim(png_structrp png_ptr, png_uint_32 owner, int window_bits)
+png_inflate_claim(png_structrp png_ptr, png_uint_32 owner)
 {
    if (png_ptr->zowner != 0)
    {
@@ -367,6 +367,22 @@ png_inflate_claim(png_structrp png_ptr, png_uint_32 owner, int window_bits)
     */
    {
       int ret; /* zlib return code */
+#     if PNG_ZLIB_VERNUM >= 0x1240
+
+#        if defined(PNG_SET_OPTION_SUPPORTED) && \
+            defined(PNG_MAXIMUM_INFLATE_WINDOW)
+            int window_bits;
+
+            if (((png_ptr->options >> PNG_MAXIMUM_INFLATE_WINDOW) & 3) ==
+               PNG_OPTION_ON)
+               window_bits = 15;
+
+            else
+               window_bits = 0;
+#        else
+#           define window_bits 0
+#        endif
+#     endif
 
       /* Set this for safety, just in case the previous owner left pointers to
        * memory allocations.
@@ -378,8 +394,7 @@ png_inflate_claim(png_structrp png_ptr, png_uint_32 owner, int window_bits)
 
       if (png_ptr->flags & PNG_FLAG_ZSTREAM_INITIALIZED)
       {
-#        if ZLIB_VERNUM < 0x1240
-            PNG_UNUSED(window_bits)
+#        if PNG_ZLIB_VERNUM < 0x1240
             ret = inflateReset(&png_ptr->zstream);
 #        else
             ret = inflateReset2(&png_ptr->zstream, window_bits);
@@ -388,7 +403,7 @@ png_inflate_claim(png_structrp png_ptr, png_uint_32 owner, int window_bits)
 
       else
       {
-#        if ZLIB_VERNUM < 0x1240
+#        if PNG_ZLIB_VERNUM < 0x1240
             ret = inflateInit(&png_ptr->zstream);
 #        else
             ret = inflateInit2(&png_ptr->zstream, window_bits);
@@ -406,6 +421,10 @@ png_inflate_claim(png_structrp png_ptr, png_uint_32 owner, int window_bits)
 
       return ret;
    }
+
+#  ifdef window_bits
+#     undef window_bits
+#  endif
 }
 
 #ifdef PNG_READ_COMPRESSED_TEXT_SUPPORTED
@@ -560,7 +579,7 @@ png_decompress_chunk(png_structrp png_ptr,
     */
    png_alloc_size_t limit = PNG_SIZE_MAX;
 
-#  ifdef PNG_SET_USER_LIMITS_SUPPOPRTED
+#  ifdef PNG_SET_CHUNK_MALLOC_LIMIT_SUPPORTED
       if (png_ptr->user_chunk_malloc_max > 0 &&
          png_ptr->user_chunk_malloc_max < limit)
          limit = png_ptr->user_chunk_malloc_max;
@@ -578,14 +597,8 @@ png_decompress_chunk(png_structrp png_ptr,
       if (limit < *newlength)
          *newlength = limit;
 
-      /* Now try to claim the stream; the 'warn' setting causes zlib to be told
-       * to use the maximum window size during inflate; this hides errors in the
-       * deflate header window bits value which is used if '0' is passed.  In
-       * fact this only has an effect with zlib versions 1.2.4 and later - see
-       * the comments in png_inflate_claim above.
-       */
-      ret = png_inflate_claim(png_ptr, png_ptr->chunk_name,
-         png_ptr->flags & PNG_FLAG_BENIGN_ERRORS_WARN ? 15 : 0);
+      /* Now try to claim the stream. */
+      ret = png_inflate_claim(png_ptr, png_ptr->chunk_name);
 
       if (ret == Z_OK)
       {
@@ -1355,8 +1368,7 @@ png_handle_iCCP(png_structrp png_ptr, png_inforp info_ptr, png_uint_32 length)
          {
             read_length -= keyword_length+2;
 
-            if (png_inflate_claim(png_ptr, png_iCCP,
-               png_ptr->flags & PNG_FLAG_BENIGN_ERRORS_WARN ? 15 : 0) == Z_OK)
+            if (png_inflate_claim(png_ptr, png_iCCP) == Z_OK)
             {
                Byte profile_header[132];
                Byte local_buffer[PNG_INFLATE_BUF_SIZE];
@@ -1580,8 +1592,7 @@ png_handle_sPLT(png_structrp png_ptr, png_inforp info_ptr, png_uint_32 length)
 
       if (--png_ptr->user_chunk_cache_max == 1)
       {
-         /* Warn the first time */
-         png_chunk_benign_error(png_ptr, "chunk cache full");
+         png_warning(png_ptr, "No space in chunk cache for sPLT");
          png_crc_finish(png_ptr, length);
          return;
       }
@@ -1831,8 +1842,6 @@ png_handle_tRNS(png_structrp png_ptr, png_inforp info_ptr, png_uint_32 length)
     */
    png_set_tRNS(png_ptr, info_ptr, readbuf, png_ptr->num_trans,
        &(png_ptr->trans_color));
-
-   png_ptr->trans_alpha = info_ptr->trans_alpha;
 }
 #endif
 
@@ -2371,7 +2380,7 @@ png_handle_tEXt(png_structrp png_ptr, png_inforp info_ptr, png_uint_32 length)
       if (--png_ptr->user_chunk_cache_max == 1)
       {
          png_crc_finish(png_ptr, length);
-         png_chunk_benign_error(png_ptr, "chunk cache full");
+         png_chunk_benign_error(png_ptr, "no space in chunk cache");
          return;
       }
    }
@@ -2450,7 +2459,7 @@ png_handle_zTXt(png_structrp png_ptr, png_inforp info_ptr, png_uint_32 length)
       if (--png_ptr->user_chunk_cache_max == 1)
       {
          png_crc_finish(png_ptr, length);
-         png_chunk_benign_error(png_ptr, "chunk cache full");
+         png_chunk_benign_error(png_ptr, "no space in chunk cache");
          return;
       }
    }
@@ -2559,7 +2568,7 @@ png_handle_iTXt(png_structrp png_ptr, png_inforp info_ptr, png_uint_32 length)
       if (--png_ptr->user_chunk_cache_max == 1)
       {
          png_crc_finish(png_ptr, length);
-         png_chunk_benign_error(png_ptr, "chunk cache full");
+         png_chunk_benign_error(png_ptr, "no space in chunk cache");
          return;
       }
    }
@@ -2699,7 +2708,7 @@ png_cache_unknown_chunk(png_structrp png_ptr, png_uint_32 length)
       png_ptr->unknown_chunk.data = NULL;
    }
 
-#  ifdef PNG_SET_USER_LIMITS_SUPPOPRTED
+#  ifdef PNG_SET_CHUNK_MALLOC_LIMIT_SUPPORTED
       if (png_ptr->user_chunk_malloc_max > 0 &&
          png_ptr->user_chunk_malloc_max < limit)
          limit = png_ptr->user_chunk_malloc_max;
@@ -2805,21 +2814,26 @@ png_handle_unknown(png_structrp png_ptr, png_inforp info_ptr,
             {
                /* If the keep value is 'default' or 'never' override it, but
                 * still error out on critical chunks unless the keep value is
-                * 'always'  While this is weird it is the behavior in 1.4.12.  A
-                * possible improvement would be to obey the value set for the
+                * 'always'  While this is weird it is the behavior in 1.4.12.
+                * A possible improvement would be to obey the value set for the
                 * chunk, but this would be an API change that would probably
                 * damage some applications.
                 *
                 * The png_app_warning below catches the case that matters, where
-                * the application has neither set specific save for this chunk
-                * or global save.
+                * the application has not set specific save or ignore for this
+                * chunk or global save or ignore.
                 */
                if (keep < PNG_HANDLE_CHUNK_IF_SAFE)
                {
 #                 ifdef PNG_SET_UNKNOWN_CHUNKS_SUPPORTED
                      if (png_ptr->unknown_default < PNG_HANDLE_CHUNK_IF_SAFE)
+                     {
+                        png_chunk_warning(png_ptr, "Saving unknown chunk:");
                         png_app_warning(png_ptr,
- "forcing save of an unhandled chunk; please call png_set_keep_unknown_chunks");
+                           "forcing save of an unhandled chunk;"
+                           " please call png_set_keep_unknown_chunks");
+                           /* with keep = PNG_HANDLE_CHUNK_IF_SAFE */
+                     }
 #                 endif
                   keep = PNG_HANDLE_CHUNK_IF_SAFE;
                }
@@ -2853,7 +2867,7 @@ png_handle_unknown(png_structrp png_ptr, png_inforp info_ptr,
 
          if (keep == PNG_HANDLE_CHUNK_ALWAYS ||
             (keep == PNG_HANDLE_CHUNK_IF_SAFE &&
-             PNG_CHUNK_ANCILLIARY(png_ptr->chunk_name)))
+             PNG_CHUNK_ANCILLARY(png_ptr->chunk_name)))
          {
             if (!png_cache_unknown_chunk(png_ptr, length))
                keep = PNG_HANDLE_CHUNK_NEVER;
@@ -2887,14 +2901,14 @@ png_handle_unknown(png_structrp png_ptr, png_inforp info_ptr,
        */
       if (keep == PNG_HANDLE_CHUNK_ALWAYS ||
          (keep == PNG_HANDLE_CHUNK_IF_SAFE &&
-          PNG_CHUNK_ANCILLIARY(png_ptr->chunk_name)))
+          PNG_CHUNK_ANCILLARY(png_ptr->chunk_name)))
       {
 #     ifdef PNG_USER_LIMITS_SUPPORTED
          switch (png_ptr->user_chunk_cache_max)
          {
             case 2:
                png_ptr->user_chunk_cache_max = 1;
-               png_chunk_benign_error(png_ptr, "chunk cache full");
+               png_chunk_benign_error(png_ptr, "no space in chunk cache");
                /* FALL THROUGH */
             case 1:
                /* NOTE: prior to 1.6.0 this case resulted in an unknown critical
@@ -3351,7 +3365,7 @@ png_combine_row(png_const_structrp png_ptr, png_bytep dp, int display)
                      png_uint_32p dp32 = png_aligncast(png_uint_32p,dp);
                      png_const_uint_32p sp32 = png_aligncastconst(
                         png_const_uint_32p, sp);
-                     unsigned int skip = (bytes_to_jump-bytes_to_copy) /
+                     size_t skip = (bytes_to_jump-bytes_to_copy) /
                         (sizeof (png_uint_32));
 
                      do
@@ -3393,7 +3407,7 @@ png_combine_row(png_const_structrp png_ptr, png_bytep dp, int display)
                      png_uint_16p dp16 = png_aligncast(png_uint_16p, dp);
                      png_const_uint_16p sp16 = png_aligncastconst(
                         png_const_uint_16p, sp);
-                     unsigned int skip = (bytes_to_jump-bytes_to_copy) /
+                     size_t skip = (bytes_to_jump-bytes_to_copy) /
                         (sizeof (png_uint_16));
 
                      do
@@ -3979,7 +3993,7 @@ png_read_IDAT_data(png_structrp png_ptr, png_bytep output,
          png_ptr->zstream.avail_out = out;
       }
 
-      else /* check for end */
+      else /* after last row, checking for end */
       {
          png_ptr->zstream.next_out = tmpbuf;
          png_ptr->zstream.avail_out = (sizeof tmpbuf);
@@ -3994,10 +4008,13 @@ png_read_IDAT_data(png_structrp png_ptr, png_bytep output,
        */
       ret = inflate(&png_ptr->zstream, Z_NO_FLUSH);
 
-      /* Take the unconsumed output back (so, in the 'check' case this just
-       * counts up).
-       */
-      avail_out += png_ptr->zstream.avail_out;
+      /* Take the unconsumed output back. */
+      if (output != NULL)
+         avail_out += png_ptr->zstream.avail_out;
+
+      else /* avail_out counts the extra bytes */
+         avail_out += (sizeof tmpbuf) - png_ptr->zstream.avail_out;
+
       png_ptr->zstream.avail_out = 0;
 
       if (ret == Z_STREAM_END)
@@ -4036,7 +4053,7 @@ png_read_IDAT_data(png_structrp png_ptr, png_bytep output,
       if (output != NULL)
          png_error(png_ptr, "Not enough image data");
 
-      else /* checking */
+      else /* the deflate stream contained extra data */
          png_chunk_benign_error(png_ptr, "Too much image data");
    }
 }
@@ -4371,7 +4388,7 @@ defined(PNG_USER_TRANSFORM_PTR_SUPPORTED)
       png_error(png_ptr, "This image requires a row greater than 64KB");
 #endif
 
-   if (row_bytes + 48 > png_ptr->big_row_buf_size)
+   if (row_bytes + 48 > png_ptr->old_big_row_buf_size)
    {
      png_free(png_ptr, png_ptr->big_row_buf);
      png_free(png_ptr, png_ptr->big_prev_row);
@@ -4408,7 +4425,7 @@ defined(PNG_USER_TRANSFORM_PTR_SUPPORTED)
      png_ptr->row_buf = png_ptr->big_row_buf + 31;
      png_ptr->prev_row = png_ptr->big_prev_row + 31;
 #endif
-     png_ptr->big_row_buf_size = row_bytes + 48;
+     png_ptr->old_big_row_buf_size = row_bytes + 48;
    }
 
 #ifdef PNG_MAX_MALLOC_64K
@@ -4447,9 +4464,10 @@ defined(PNG_USER_TRANSFORM_PTR_SUPPORTED)
     * IDAT stream has a bogus deflate header window_bits value, but this should
     * not be happening any longer!)
     */
-   if (png_inflate_claim(png_ptr, png_IDAT, 0) != Z_OK)
+   if (png_inflate_claim(png_ptr, png_IDAT) != Z_OK)
       png_error(png_ptr, png_ptr->zstream.msg);
 
    png_ptr->flags |= PNG_FLAG_ROW_INIT;
 }
+
 #endif /* PNG_READ_SUPPORTED */

pngset.c

@@ -1,7 +1,7 @@
 
 /* pngset.c - storage of image information into info struct
  *
- * Last changed in libpng 1.7.0 [(PENDING RELEASE)]
+ * Last changed in libpng 1.6.2 [April 25, 2013]
  * Copyright (c) 1998-2013 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.)
@@ -431,8 +431,7 @@ png_set_sCAL_s(png_const_structrp png_ptr, png_inforp info_ptr,
    info_ptr->free_me |= PNG_FREE_SCAL;
 }
 
-#  if defined PNG_FLOATING_POINT_SUPPORTED &&\
-      defined PNG_FLOATING_ARITHMETIC_SUPPORTED
+#  ifdef PNG_FLOATING_POINT_SUPPORTED
 void PNGAPI
 png_set_sCAL(png_const_structrp png_ptr, png_inforp info_ptr, int unit,
     double width, double height)
@@ -515,7 +514,7 @@ png_set_PLTE(png_structrp png_ptr, png_inforp info_ptr,
 
    png_debug1(1, "in %s storage function", "PLTE");
 
-   if (png_ptr == NULL || info_ptr == NULL || palette == NULL)
+   if (png_ptr == NULL || info_ptr == NULL)
       return;
 
    if (num_palette < 0 || num_palette > PNG_MAX_PALETTE_LENGTH)
@@ -530,6 +529,17 @@ png_set_PLTE(png_structrp png_ptr, png_inforp info_ptr,
       }
    }
 
+   if ((num_palette > 0 && palette == NULL) ||
+      (num_palette == 0
+#        ifdef PNG_MNG_FEATURES_SUPPORTED
+            && (png_ptr->mng_features_permitted & PNG_FLAG_MNG_EMPTY_PLTE) == 0
+#        endif
+      ))
+   {
+      png_chunk_report(png_ptr, "Invalid palette", PNG_CHUNK_ERROR);
+      return;
+   }
+
    /* It may not actually be necessary to set png_ptr->palette here;
     * we do it for backward compatibility with the way the png_handle_tRNS
     * function used to do the allocation.
@@ -546,7 +556,8 @@ png_set_PLTE(png_structrp png_ptr, png_inforp info_ptr,
    png_ptr->palette = png_voidcast(png_colorp, png_calloc(png_ptr,
        PNG_MAX_PALETTE_LENGTH * (sizeof (png_color))));
 
-   memcpy(png_ptr->palette, palette, num_palette * (sizeof (png_color)));
+   if (num_palette > 0)
+      memcpy(png_ptr->palette, palette, num_palette * (sizeof (png_color)));
    info_ptr->palette = png_ptr->palette;
    info_ptr->num_palette = png_ptr->num_palette = (png_uint_16)num_palette;
 
@@ -915,90 +926,52 @@ png_set_tRNS(png_structrp png_ptr, png_inforp info_ptr,
    if (png_ptr == NULL || info_ptr == NULL)
       return;
 
-   if (info_ptr->color_type & PNG_COLOR_MASK_ALPHA)
-      png_chunk_report(png_ptr,
-         "png_set_tRNS: invalid on PNG with alpha channel", PNG_CHUNK_ERROR);
-
-   else if (info_ptr->color_type & PNG_COLOR_MASK_PALETTE)
+   if (trans_alpha != NULL)
    {
-      int max_num;
+       /* It may not actually be necessary to set png_ptr->trans_alpha here;
+        * we do it for backward compatibility with the way the png_handle_tRNS
+        * function used to do the allocation.
+        *
+        * 1.6.0: The above statement is incorrect; png_handle_tRNS effectively
+        * relies on png_set_tRNS storing the information in png_struct
+        * (otherwise it won't be there for the code in pngrtran.c).
+        */
 
-      /* Free the old data; num_trans 0 can be used to kill the tRNS */
-      png_free_data(png_ptr, info_ptr, PNG_FREE_TRNS, 0);
+       png_free_data(png_ptr, info_ptr, PNG_FREE_TRNS, 0);
 
-      /* Do this just in case the old data was not owned by libpng: */
-      info_ptr->valid &= ~PNG_INFO_tRNS;
-      info_ptr->trans_alpha = NULL;
-      info_ptr->num_trans = 0;
+       /* Changed from num_trans to PNG_MAX_PALETTE_LENGTH in version 1.2.1 */
+       png_ptr->trans_alpha = info_ptr->trans_alpha = png_voidcast(png_bytep,
+         png_malloc(png_ptr, PNG_MAX_PALETTE_LENGTH));
 
-      /* Expect png_set_PLTE to happen before png_set_tRNS, so num_palette will
-       * be set, but this is not a requirement of the API.
-       */
-      if (png_ptr->num_palette)
-         max_num = png_ptr->num_palette;
-
-      else
-         max_num = 1 << png_ptr->bit_depth;
-
-      if (num_trans > max_num)
-      {
-         png_chunk_report(png_ptr, "png_set_tRNS: num_trans too large",
-            PNG_CHUNK_ERROR);
-         /* If control returns simply limit it; the behavior prior to 1.7 was to
-          * issue a warning and skip the palette in png_write_tRNS.
-          */
-         num_trans = max_num;
-      }
-
-      /* But only attempt a malloc if there is something to do; so the app can
-       * set a tRNS array then later delete it.
-       */
-      if (num_trans > 0 && trans_alpha != NULL)
-      {
-         /* Changed from num_trans to PNG_MAX_PALETTE_LENGTH in version 1.2.1,
-          * this avoids issues where a palette image contains out of range
-          * indices.
-          */
-         info_ptr->trans_alpha = png_voidcast(png_bytep, png_malloc(png_ptr,
-            PNG_MAX_PALETTE_LENGTH));
-         info_ptr->free_me |= PNG_FREE_TRNS;
-
-         memcpy(info_ptr->trans_alpha, trans_alpha,
-            (unsigned)/*SAFE*/num_trans);
-         info_ptr->valid |= PNG_INFO_tRNS;
-         info_ptr->num_trans = (png_uint_16)num_trans; /* SAFE */
-      }
+       if (num_trans > 0 && num_trans <= PNG_MAX_PALETTE_LENGTH)
+          memcpy(info_ptr->trans_alpha, trans_alpha, (png_size_t)num_trans);
    }
 
-   else /* not a PALETTE image */
+   if (trans_color != NULL)
    {
-      /* Invalidate any prior transparent color, set num_trans too, it is not
-       * used internally in this case but png_get_tRNS still returns it.
-       */
-      info_ptr->valid &= ~PNG_INFO_tRNS;
-      info_ptr->num_trans = 0; /* for png_get_tRNS */
+      int sample_max = (1 << info_ptr->bit_depth);
 
-      if (trans_color != NULL)
-      {
-         int sample_max = (1 << info_ptr->bit_depth);
+      if ((info_ptr->color_type == PNG_COLOR_TYPE_GRAY &&
+          trans_color->gray > sample_max) ||
+          (info_ptr->color_type == PNG_COLOR_TYPE_RGB &&
+          (trans_color->red > sample_max ||
+          trans_color->green > sample_max ||
+          trans_color->blue > sample_max)))
+         png_warning(png_ptr,
+            "tRNS chunk has out-of-range samples for bit_depth");
 
-         if ((info_ptr->color_type == PNG_COLOR_TYPE_GRAY &&
-             trans_color->gray <= sample_max) ||
-             (info_ptr->color_type == PNG_COLOR_TYPE_RGB &&
-             trans_color->red <= sample_max &&
-             trans_color->green <= sample_max &&
-             trans_color->blue <= sample_max))
-         {
-            info_ptr->trans_color = *trans_color;
-            info_ptr->valid |= PNG_INFO_tRNS;
-            info_ptr->num_trans = 1; /* for png_get_tRNS */
-         }
+      info_ptr->trans_color = *trans_color;
 
-         else
-            png_chunk_report(png_ptr,
-               "tRNS chunk has out-of-range samples for bit_depth",
-               PNG_CHUNK_ERROR);
-      }
+      if (num_trans == 0)
+         num_trans = 1;
+   }
+
+   info_ptr->num_trans = (png_uint_16)num_trans;
+
+   if (num_trans != 0)
+   {
+      info_ptr->valid |= PNG_INFO_tRNS;
+      info_ptr->free_me |= PNG_FREE_TRNS;
    }
 }
 #endif
@@ -1155,16 +1128,16 @@ png_set_unknown_chunks(png_const_structrp png_ptr,
     * code) but may be meaningless if the read or write handling of unknown
     * chunks is not compiled in.
     */
-#  if !(defined PNG_READ_UNKNOWN_CHUNKS_SUPPORTED) && \
-      (defined PNG_READ_SUPPORTED)
+#  if !defined(PNG_READ_UNKNOWN_CHUNKS_SUPPORTED) && \
+      defined(PNG_READ_SUPPORTED)
       if (png_ptr->mode & PNG_IS_READ_STRUCT)
       {
          png_app_error(png_ptr, "no unknown chunk support on read");
          return;
       }
 #  endif
-#  if !(defined PNG_WRITE_UNKNOWN_CHUNKS_SUPPORTED) && \
-      (defined PNG_WRITE_SUPPORTED)
+#  if !defined(PNG_WRITE_UNKNOWN_CHUNKS_SUPPORTED) && \
+      defined(PNG_WRITE_SUPPORTED)
       if (!(png_ptr->mode & PNG_IS_READ_STRUCT))
       {
          png_app_error(png_ptr, "no unknown chunk support on write");
@@ -1561,19 +1534,19 @@ png_set_user_limits (png_structrp png_ptr, png_uint_32 user_width_max,
     * rejected by png_set_IHDR().  To accept any PNG datastream
     * regardless of dimensions, set both limits to 0x7ffffffL.
     */
-   if (png_ptr != NULL)
-   {
-      png_ptr->user_width_max = user_width_max;
-      png_ptr->user_height_max = user_height_max;
-   }
+   if (png_ptr == NULL)
+      return;
+
+   png_ptr->user_width_max = user_width_max;
+   png_ptr->user_height_max = user_height_max;
 }
 
 /* This function was added to libpng 1.4.0 */
 void PNGAPI
 png_set_chunk_cache_max (png_structrp png_ptr, png_uint_32 user_chunk_cache_max)
 {
-   if (png_ptr != NULL)
-      png_ptr->user_chunk_cache_max = user_chunk_cache_max;
+    if (png_ptr)
+       png_ptr->user_chunk_cache_max = user_chunk_cache_max;
 }
 
 /* This function was added to libpng 1.4.1 */
@@ -1581,7 +1554,7 @@ void PNGAPI
 png_set_chunk_malloc_max (png_structrp png_ptr,
     png_alloc_size_t user_chunk_malloc_max)
 {
-   if (png_ptr != NULL)
+   if (png_ptr)
       png_ptr->user_chunk_malloc_max = user_chunk_malloc_max;
 }
 #endif /* ?PNG_SET_USER_LIMITS_SUPPORTED */

pngstruct.h

@@ -1,11 +1,11 @@
 
 /* pngstruct.h - header file for PNG reference library
  *
- * Copyright (c) 1998-2012 Glenn Randers-Pehrson
+ * Copyright (c) 1998-2013 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.)
  *
- * Last changed in libpng 1.6.0 [(PENDING RELEASE)]
+ * Last changed in libpng 1.6.1 [March 28, 2013]
  *
  * This code is released under the libpng license.
  * For conditions of distribution and use, see the disclaimer
@@ -28,7 +28,7 @@
    /* We must ensure that zlib uses 'const' in declarations. */
 #  define ZLIB_CONST
 #endif
-#include PNG_ZLIB_HEADER
+#include "zlib.h"
 #ifdef const
    /* zlib.h sometimes #defines const to nothing, undo this. */
 #  undef const
@@ -48,10 +48,10 @@
 /* zlib.h declares a magic type 'uInt' that limits the amount of data that zlib
  * can handle at once.  This type need be no larger than 16 bits (so maximum of
  * 65535), this define allows us to discover how big it is, but limited by the
- * maximum for size_t. The value can be overridden in a library build (pngusr.h,
- * or set it in CPPFLAGS) and it works to set it to a considerably lower value
- * (e.g. 255 works).  A lower value may help memory usage (slightly) and may
- * even improve performance on some systems (and degrade it on others.)
+ * maximuum for png_size_t.  The value can be overriden in a library build
+ * (pngusr.h, or set it in CPPFLAGS) and it works to set it to a considerably
+ * lower value (e.g. 255 works).  A lower value may help memory usage (slightly)
+ * and may even improve performance on some systems (and degrade it on others.)
  */
 #ifndef ZLIB_IO_MAX
 #  define ZLIB_IO_MAX ((uInt)-1)
@@ -100,7 +100,7 @@ typedef struct png_XYZ
 } png_XYZ;
 #endif /* COLORSPACE */
 
-#if defined PNG_COLORSPACE_SUPPORTED || defined PNG_GAMMA_SUPPORTED
+#if defined(PNG_COLORSPACE_SUPPORTED) || defined(PNG_GAMMA_SUPPORTED)
 /* A colorspace is all the above plus, potentially, profile information,
  * however at present libpng does not use the profile internally so it is only
  * stored in the png_info struct (if iCCP is supported.)  The rendering intent
@@ -137,239 +137,318 @@ typedef const png_colorspace * PNG_RESTRICT png_const_colorspacerp;
 #define PNG_COLORSPACE_FROM_sRGB            0x0020
 #define PNG_COLORSPACE_ENDPOINTS_MATCH_sRGB 0x0040
 #define PNG_COLORSPACE_MATCHES_sRGB         0x0080 /* exact match on profile */
-#define PNG_COLORSPACE_RGB_TO_GRAY_SET      0x0100 /* user specified coeffs */
 #define PNG_COLORSPACE_INVALID              0x8000
 #define PNG_COLORSPACE_CANCEL(flags)        (0xffff ^ (flags))
 #endif /* COLORSPACE || GAMMA */
 
 struct png_struct_def
 {
-   /* Rearranged in libpng 1.7 to attempt to lessen padding; in general
-    * (char), (short), (int) and pointer types are kept separate, however
-    * associated members under the control of the same #define are still
-    * together.
-    */
 #ifdef PNG_SETJMP_SUPPORTED
-   /* jmp_buf can have very high alignment requirements on some systems, so put
-    * it first (the other setjmp members are later as they are infrequently
-    * accesed.)
-    */
-   jmp_buf jmp_buf_local;
+   jmp_buf jmp_buf_local;     /* New name in 1.6.0 for jmp_buf in png_struct */
+   png_longjmp_ptr longjmp_fn;/* setjmp non-local goto function. */
+   jmp_buf *jmp_buf_ptr;      /* passed to longjmp_fn */
+   size_t jmp_buf_size;       /* size of the above, if allocated */
+#endif
+   png_error_ptr error_fn;    /* function for printing errors and aborting */
+#ifdef PNG_WARNINGS_SUPPORTED
+   png_error_ptr warning_fn;  /* function for printing warnings */
+#endif
+   png_voidp error_ptr;       /* user supplied struct for error functions */
+   png_rw_ptr write_data_fn;  /* function for writing output data */
+   png_rw_ptr read_data_fn;   /* function for reading input data */
+   png_voidp io_ptr;          /* ptr to application struct for I/O functions */
+
+#ifdef PNG_READ_USER_TRANSFORM_SUPPORTED
+   png_user_transform_ptr read_user_transform_fn; /* user read transform */
 #endif
 
-   /* Next the frequently accessed fields.  Many processors perform arithmetic
-    * in the address pipeline, but frequently the amount of addition or
-    * subtraction is limited.  By putting these fields at the head of png_struct
-    * the hope is that such processors will generate code that is both smaller
-    * and faster.
-    */
-   png_colorp  palette;        /* palette from the input file */
-   size_t      rowbytes;       /* size of row in bytes */
-   size_t      info_rowbytes;  /* cache of updated row bytes */
-   png_uint_32 width;          /* width of image in pixels */
-   png_uint_32 height;         /* height of image in pixels */
-   png_uint_32 num_rows;       /* number of rows in current pass */
-   png_uint_32 usr_width;      /* width of row at start of write */
-   png_uint_32 iwidth;         /* width of current interlaced row in pixels */
-   png_uint_32 row_number;     /* current row in interlace pass */
-   png_uint_32 chunk_name;     /* PNG_CHUNK() id of current chunk */
-   png_uint_32 crc;            /* current chunk CRC value */
-   png_uint_32 mode;           /* tells us where we are in the PNG file */
-   png_uint_32 flags;          /* flags indicating various things to libpng */
-   png_uint_32 transformations;/* which transformations to perform */
-   png_uint_32 zowner;         /* ID (chunk type) of zstream owner, 0 if none */
-   png_uint_32 free_me;        /* items libpng is responsible for freeing */
-
-   int         maximum_pixel_depth; /* pixel depth used for the row buffers */
-#ifdef PNG_CHECK_FOR_INVALID_INDEX_SUPPORTED
-   int         num_palette_max;     /* maximum palette index found in IDAT */
+#ifdef PNG_WRITE_USER_TRANSFORM_SUPPORTED
+   png_user_transform_ptr write_user_transform_fn; /* user write transform */
 #endif
 
+/* These were added in libpng-1.0.2 */
+#ifdef PNG_USER_TRANSFORM_PTR_SUPPORTED
+#if defined(PNG_READ_USER_TRANSFORM_SUPPORTED) || \
+    defined(PNG_WRITE_USER_TRANSFORM_SUPPORTED)
+   png_voidp user_transform_ptr; /* user supplied struct for user transform */
+   png_byte user_transform_depth;    /* bit depth of user transformed pixels */
+   png_byte user_transform_channels; /* channels in user transformed pixels */
+#endif
+#endif
+
+   png_uint_32 mode;          /* tells us where we are in the PNG file */
+   png_uint_32 flags;         /* flags indicating various things to libpng */
+   png_uint_32 transformations; /* which transformations to perform */
+
+   png_uint_32 zowner;        /* ID (chunk type) of zstream owner, 0 if none */
+   z_stream    zstream;       /* decompression structure */
+
+#ifdef PNG_WRITE_SUPPORTED
+   png_compression_bufferp zbuffer_list; /* Created on demand during write */
+   uInt                    zbuffer_size; /* size of the actual buffer */
+
+   int zlib_level;            /* holds zlib compression level */
+   int zlib_method;           /* holds zlib compression method */
+   int zlib_window_bits;      /* holds zlib compression window bits */
+   int zlib_mem_level;        /* holds zlib compression memory level */
+   int zlib_strategy;         /* holds zlib compression strategy */
+#endif
+/* Added at libpng 1.5.4 */
+#ifdef PNG_WRITE_CUSTOMIZE_ZTXT_COMPRESSION_SUPPORTED
+   int zlib_text_level;            /* holds zlib compression level */
+   int zlib_text_method;           /* holds zlib compression method */
+   int zlib_text_window_bits;      /* holds zlib compression window bits */
+   int zlib_text_mem_level;        /* holds zlib compression memory level */
+   int zlib_text_strategy;         /* holds zlib compression strategy */
+#endif
+/* End of material added at libpng 1.5.4 */
+/* Added at libpng 1.6.0 */
+#ifdef PNG_WRITE_SUPPORTED
+   int zlib_set_level;        /* Actual values set into the zstream on write */
+   int zlib_set_method;
+   int zlib_set_window_bits;
+   int zlib_set_mem_level;
+   int zlib_set_strategy;
+#endif
+
+   png_uint_32 width;         /* width of image in pixels */
+   png_uint_32 height;        /* height of image in pixels */
+   png_uint_32 num_rows;      /* number of rows in current pass */
+   png_uint_32 usr_width;     /* width of row at start of write */
+   png_size_t rowbytes;       /* size of row in bytes */
+   png_uint_32 iwidth;        /* width of current interlaced row in pixels */
+   png_uint_32 row_number;    /* current row in interlace pass */
+   png_uint_32 chunk_name;    /* PNG_CHUNK() id of current chunk */
+   png_bytep prev_row;        /* buffer to save previous (unfiltered) row.
+                               * This is a pointer into big_prev_row
+                               */
+   png_bytep row_buf;         /* buffer to save current (unfiltered) row.
+                               * This is a pointer into big_row_buf
+                               */
+#ifdef PNG_WRITE_SUPPORTED
+   png_bytep sub_row;         /* buffer to save "sub" row when filtering */
+   png_bytep up_row;          /* buffer to save "up" row when filtering */
+   png_bytep avg_row;         /* buffer to save "avg" row when filtering */
+   png_bytep paeth_row;       /* buffer to save "Paeth" row when filtering */
+#endif
+   png_size_t info_rowbytes;  /* Added in 1.5.4: cache of updated row bytes */
+
+   png_uint_32 idat_size;     /* current IDAT size for read */
+   png_uint_32 crc;           /* current chunk CRC value */
+   png_colorp palette;        /* palette from the input file */
    png_uint_16 num_palette;   /* number of color entries in palette */
-   png_uint_16 num_trans;     /* number of transparency values */
 
-   /* Single byte values, typically used either to save space or to hold 1-byte
-    * values from the PNG chunk specifications.
-    */
-   png_byte compression_type; /* file compression type (always 0) */
+/* Added at libpng-1.5.10 */
+#ifdef PNG_CHECK_FOR_INVALID_INDEX_SUPPORTED
+   int num_palette_max;       /* maximum palette index found in IDAT */
+#endif
+
+   png_uint_16 num_trans;     /* number of transparency values */
+   png_byte compression;      /* file compression type (always 0) */
    png_byte filter;           /* file filter type (always 0) */
    png_byte interlaced;       /* PNG_INTERLACE_NONE, PNG_INTERLACE_ADAM7 */
    png_byte pass;             /* current interlace pass (0 - 6) */
    png_byte do_filter;        /* row filter flags (see PNG_FILTER_ below ) */
    png_byte color_type;       /* color type of file */
    png_byte bit_depth;        /* bit depth of file */
+   png_byte usr_bit_depth;    /* bit depth of users row: write only */
    png_byte pixel_depth;      /* number of bits per pixel */
    png_byte channels;         /* number of channels in file */
+#ifdef PNG_WRITE_SUPPORTED
+   png_byte usr_channels;     /* channels at start of write: write only */
+#endif
    png_byte sig_bytes;        /* magic bytes read/written from start of file */
+   png_byte maximum_pixel_depth;
+                              /* pixel depth used for the row buffers */
    png_byte transformed_pixel_depth;
                               /* pixel depth after read/write transforms */
-
-   /* ERROR HANDLING */
-#ifdef PNG_SETJMP_SUPPORTED
-   jmp_buf        *jmp_buf_ptr;   /* passed to longjmp_fn */
-   png_longjmp_ptr longjmp_fn;    /* setjmp non-local goto function. */
-   size_t          jmp_buf_size;  /* size of *jmp_buf_ptr, if allocated */
+#if defined(PNG_READ_FILLER_SUPPORTED) || defined(PNG_WRITE_FILLER_SUPPORTED)
+   png_uint_16 filler;           /* filler bytes for pixel expansion */
 #endif
 
-   /* Error/warning callbacks */
-   png_error_ptr error_fn;        /* print an error message and abort */
-#ifdef PNG_WARNINGS_SUPPORTED
-   png_error_ptr warning_fn;      /* print a warning and continue */
-#endif
-   png_voidp     error_ptr;       /* user supplied data for the above */
-
-   /* MEMORY ALLOCATION */
-#ifdef PNG_USER_MEM_SUPPORTED
-   png_malloc_ptr malloc_fn; /* allocate memory */
-   png_free_ptr   free_fn;   /* free memory */
-   png_voidp      mem_ptr;   /* user supplied data for the above */
-#endif
-
-   /* IO and BASIC READ/WRITE SUPPORT */
-   png_voidp            io_ptr;       /* user supplied data for IO callbacks */
-
-#ifdef PNG_READ_SUPPORTED
-   png_rw_ptr          read_data_fn;  /* read some bytes (must succeed) */
-   png_read_status_ptr read_row_fn;   /* called after each row is decoded */
-   png_bytep           read_buffer;   /* buffer for reading chunk data */
-
-   /* During read the following array is set up to point to the appropriate
-    * un-filter function, this allows per-image and per-processor optimization.
-    */
-   void (*read_filter[PNG_FILTER_VALUE_LAST-1])(png_row_infop row_info,
-      png_bytep row, png_const_bytep prev_row);
-
-#if (defined PNG_COLORSPACE_SUPPORTED || defined PNG_GAMMA_SUPPORTED)
-   /* The png_struct colorspace structure is only required on read - on write it
-    * is in (just) the info_struct.
-    */
-   png_colorspace   colorspace;
-#endif
-#endif /* PNG_READ_SUPPORTED */
-
-#ifdef PNG_SET_USER_LIMITS_SUPPORTED
-   png_uint_32 user_width_max;        /* Maximum width on read */
-   png_uint_32 user_height_max;       /* Maximum height on read */
-   /* Total memory that a single zTXt, sPLT, iTXt, iCCP, or unknown chunk
-    * can occupy when decompressed.  0 means unlimited.  This field is a counter
-    * - it is decremented as memory is allocated.
-    */
-   png_alloc_size_t user_chunk_malloc_max;
-#endif
-#ifdef PNG_USER_LIMITS_SUPPORTED
-   /* limit on total *number* of sPLT, text and unknown chunks that can be
-    * stored.  0 means unlimited.  This field is a counter - it is decremented
-    * as chunks are encountered.
-    */
-   png_uint_32 user_chunk_cache_max;
-#endif
-
-   /* The progressive reader gets passed data and calls application handling
-    * functions when appropriate.
-    */
-#ifdef PNG_PROGRESSIVE_READ_SUPPORTED
-   png_progressive_info_ptr info_fn; /* called after header data fully read */
-   png_progressive_row_ptr  row_fn;  /* called after a row is decoded */
-   png_progressive_end_ptr  end_fn;  /* called after image is complete */
-
-   /* Progressive read control data */
-   png_bytep   save_buffer_ptr;      /* current location in save_buffer */
-   png_bytep   save_buffer;          /* buffer for previously read data */
-   png_bytep   current_buffer_ptr;   /* current location in current_buffer */
-   png_bytep   current_buffer;       /* buffer for recently used data */
-
-   size_t      save_buffer_size;     /* amount of data now in save_buffer */
-   size_t      save_buffer_max;      /* total size of save_buffer */
-   size_t      buffer_size;          /* total amount of available input data */
-   size_t      current_buffer_size;  /* amount of data now in current_buffer */
-
-   png_uint_32 push_length;          /* size of current input chunk */
-   png_uint_32 skip_length;          /* bytes to skip in input data */
-
-   int         process_mode;         /* what push library is currently doing */
-   int         cur_palette;          /* current push library palette index */
-#endif
-
-#ifdef PNG_WRITE_SUPPORTED
-   png_rw_ptr              write_data_fn;/* write some bytes (must succeed) */
-   png_write_status_ptr    write_row_fn; /* called after each row is encoded */
+#if defined(PNG_bKGD_SUPPORTED) || defined(PNG_READ_BACKGROUND_SUPPORTED) ||\
+   defined(PNG_READ_ALPHA_MODE_SUPPORTED)
+   png_byte background_gamma_type;
+   png_fixed_point background_gamma;
+   png_color_16 background;   /* background color in screen gamma space */
+#ifdef PNG_READ_GAMMA_SUPPORTED
+   png_color_16 background_1; /* background normalized to gamma 1.0 */
 #endif
+#endif /* PNG_bKGD_SUPPORTED */
 
 #ifdef PNG_WRITE_FLUSH_SUPPORTED
    png_flush_ptr output_flush_fn; /* Function for flushing output */
-   png_uint_32   flush_dist; /* how many rows apart to flush, 0 - no flush */
-   png_uint_32   flush_rows; /* number of rows written since last flush */
+   png_uint_32 flush_dist;    /* how many rows apart to flush, 0 - no flush */
+   png_uint_32 flush_rows;    /* number of rows written since last flush */
+#endif
+
+#ifdef PNG_READ_GAMMA_SUPPORTED
+   int gamma_shift;      /* number of "insignificant" bits in 16-bit gamma */
+   png_fixed_point screen_gamma; /* screen gamma value (display_exponent) */
+
+   png_bytep gamma_table;     /* gamma table for 8-bit depth files */
+   png_uint_16pp gamma_16_table; /* gamma table for 16-bit depth files */
+#if defined(PNG_READ_BACKGROUND_SUPPORTED) || \
+   defined(PNG_READ_ALPHA_MODE_SUPPORTED) || \
+   defined(PNG_READ_RGB_TO_GRAY_SUPPORTED)
+   png_bytep gamma_from_1;    /* converts from 1.0 to screen */
+   png_bytep gamma_to_1;      /* converts from file to 1.0 */
+   png_uint_16pp gamma_16_from_1; /* converts from 1.0 to screen */
+   png_uint_16pp gamma_16_to_1; /* converts from file to 1.0 */
+#endif /* READ_BACKGROUND || READ_ALPHA_MODE || RGB_TO_GRAY */
+#endif
+
+#if defined(PNG_READ_GAMMA_SUPPORTED) || defined(PNG_sBIT_SUPPORTED)
+   png_color_8 sig_bit;       /* significant bits in each available channel */
+#endif
+
+#if defined(PNG_READ_SHIFT_SUPPORTED) || defined(PNG_WRITE_SHIFT_SUPPORTED)
+   png_color_8 shift;         /* shift for significant bit tranformation */
+#endif
+
+#if defined(PNG_tRNS_SUPPORTED) || defined(PNG_READ_BACKGROUND_SUPPORTED) \
+ || defined(PNG_READ_EXPAND_SUPPORTED) || defined(PNG_READ_BACKGROUND_SUPPORTED)
+   png_bytep trans_alpha;           /* alpha values for paletted files */
+   png_color_16 trans_color;  /* transparent color for non-paletted files */
+#endif
+
+   png_read_status_ptr read_row_fn;   /* called after each row is decoded */
+   png_write_status_ptr write_row_fn; /* called after each row is encoded */
+#ifdef PNG_PROGRESSIVE_READ_SUPPORTED
+   png_progressive_info_ptr info_fn; /* called after header data fully read */
+   png_progressive_row_ptr row_fn;   /* called after a prog. row is decoded */
+   png_progressive_end_ptr end_fn;   /* called after image is complete */
+   png_bytep save_buffer_ptr;        /* current location in save_buffer */
+   png_bytep save_buffer;            /* buffer for previously read data */
+   png_bytep current_buffer_ptr;     /* current location in current_buffer */
+   png_bytep current_buffer;         /* buffer for recently used data */
+   png_uint_32 push_length;          /* size of current input chunk */
+   png_uint_32 skip_length;          /* bytes to skip in input data */
+   png_size_t save_buffer_size;      /* amount of data now in save_buffer */
+   png_size_t save_buffer_max;       /* total size of save_buffer */
+   png_size_t buffer_size;           /* total amount of available input data */
+   png_size_t current_buffer_size;   /* amount of data now in current_buffer */
+   int process_mode;                 /* what push library is currently doing */
+   int cur_palette;                  /* current push library palette index */
+
+#endif /* PNG_PROGRESSIVE_READ_SUPPORTED */
+
+#if defined(__TURBOC__) && !defined(_Windows) && !defined(__FLAT__)
+/* For the Borland special 64K segment handler */
+   png_bytepp offset_table_ptr;
+   png_bytep offset_table;
+   png_uint_16 offset_table_number;
+   png_uint_16 offset_table_count;
+   png_uint_16 offset_table_count_free;
+#endif
+
+#ifdef PNG_READ_QUANTIZE_SUPPORTED
+   png_bytep palette_lookup; /* lookup table for quantizing */
+   png_bytep quantize_index; /* index translation for palette files */
 #endif
 
 #ifdef PNG_WRITE_WEIGHTED_FILTER_SUPPORTED
-   png_bytep    prev_filters;        /* filter type(s) of previous row(s) */
+   png_byte heuristic_method;        /* heuristic for row filter selection */
+   png_byte num_prev_filters;        /* number of weights for previous rows */
+   png_bytep prev_filters;           /* filter type(s) of previous row(s) */
    png_uint_16p filter_weights;      /* weight(s) for previous line(s) */
    png_uint_16p inv_filter_weights;  /* 1/weight(s) for previous line(s) */
    png_uint_16p filter_costs;        /* relative filter calculation cost */
    png_uint_16p inv_filter_costs;    /* 1/relative filter calculation cost */
-   png_byte     heuristic_method;    /* heuristic for row filter selection */
-   png_byte     num_prev_filters;    /* number of weights for previous rows */
 #endif
 
-#ifdef PNG_WRITE_SUPPORTED
-   png_byte     usr_bit_depth;       /* bit depth of users row */
-   png_byte     usr_channels;        /* channels at start of write */
+   /* Options */
+#ifdef PNG_SET_OPTION_SUPPORTED
+   png_byte options;           /* On/off state (up to 4 options) */
 #endif
 
-#ifdef PNG_IO_STATE_SUPPORTED
-   png_uint_32          io_state;     /* tells the app read/write progress */
+#if PNG_LIBPNG_VER < 10700
+/* To do: remove this from libpng-1.7 */
+#ifdef PNG_TIME_RFC1123_SUPPORTED
+   char time_buffer[29]; /* String to hold RFC 1123 time text */
+#endif
 #endif
 
-   /* ROW BUFFERS
-    *
-    * Members that hold pointers to the decompressed image rows.
-    */
-   png_bytep row_buf;  /* buffer for the current (unfiltered) row */
-#if (defined PNG_WRITE_FILTER_SUPPORTED) || (defined PNG_READ_SUPPORTED)
-   png_bytep prev_row; /* buffer to save the previous (unfiltered) row */
-#endif
+/* New members added in libpng-1.0.6 */
 
-#ifdef PNG_READ_SUPPORTED
-   /* The row_buf and prev_row pointers are misaligned so that the start of the
-    * row - after the filter byte - is aligned, the 'big_' pointers record the
-    * original allocated pointer.
-    */
-   png_bytep big_row_buf;
-   png_bytep big_prev_row;
-   size_t    big_row_buf_size; /* Actual size of both */
-#endif
+   png_uint_32 free_me;    /* flags items libpng is responsible for freeing */
 
-#ifdef PNG_WRITE_SUPPORTED
-   /* This is somewhat excessive, there is no obvious reason on write to
-    * allocate a buffer for each possible filtered row, only for the one being
-    * tested and the current best.
-    *
-    * TODO: fix this
-    */
-   png_bytep sub_row;         /* buffer to save "sub" row when filtering */
-   png_bytep up_row;          /* buffer to save "up" row when filtering */
-   png_bytep avg_row;         /* buffer to save "avg" row when filtering */
-   png_bytep paeth_row;       /* buffer to save "Paeth" row when filtering */
-#endif
-
-   /* UNKNOWN CHUNK HANDLING */
-   /* TODO: this is excessively complicated, there are multiple ways of doing
-    * the same thing.  It should be cleaned up, possibly by finding out which
-    * APIs applications really use.
-    */
 #ifdef PNG_USER_CHUNKS_SUPPORTED
-   /* General purpose pointer for all user/unknown chunk handling; points to
-    * application supplied data for use in the read_user_chunk_fn callback
-    * (currently there is no write side support - the write side must use the
-    * set_unknown_chunks interface.)
-    */
    png_voidp user_chunk_ptr;
+#ifdef PNG_READ_USER_CHUNKS_SUPPORTED
+   png_user_chunk_ptr read_user_chunk_fn; /* user read chunk handler */
+#endif
 #endif
 
-#ifdef PNG_READ_USER_CHUNKS_SUPPORTED
-   /* This is called back from the unknown chunk handling */
-   png_user_chunk_ptr     read_user_chunk_fn; /* user read chunk handler */
+#ifdef PNG_SET_UNKNOWN_CHUNKS_SUPPORTED
+   int          unknown_default; /* As PNG_HANDLE_* */
+   unsigned int num_chunk_list;  /* Number of entries in the list */
+   png_bytep    chunk_list;      /* List of png_byte[5]; the textual chunk name
+                                  * followed by a PNG_HANDLE_* byte */
 #endif
+
+/* New members added in libpng-1.0.3 */
+#ifdef PNG_READ_RGB_TO_GRAY_SUPPORTED
+   png_byte rgb_to_gray_status;
+   /* Added in libpng 1.5.5 to record setting of coefficients: */
+   png_byte rgb_to_gray_coefficients_set;
+   /* These were changed from png_byte in libpng-1.0.6 */
+   png_uint_16 rgb_to_gray_red_coeff;
+   png_uint_16 rgb_to_gray_green_coeff;
+   /* deleted in 1.5.5: rgb_to_gray_blue_coeff; */
+#endif
+
+/* New member added in libpng-1.0.4 (renamed in 1.0.9) */
+#if defined(PNG_MNG_FEATURES_SUPPORTED)
+/* Changed from png_byte to png_uint_32 at version 1.2.0 */
+   png_uint_32 mng_features_permitted;
+#endif
+
+/* New member added in libpng-1.0.9, ifdef'ed out in 1.0.12, enabled in 1.2.0 */
+#ifdef PNG_MNG_FEATURES_SUPPORTED
+   png_byte filter_type;
+#endif
+
+/* New members added in libpng-1.2.0 */
+
+/* New members added in libpng-1.0.2 but first enabled by default in 1.2.0 */
+#ifdef PNG_USER_MEM_SUPPORTED
+   png_voidp mem_ptr;             /* user supplied struct for mem functions */
+   png_malloc_ptr malloc_fn;      /* function for allocating memory */
+   png_free_ptr free_fn;          /* function for freeing memory */
+#endif
+
+/* New member added in libpng-1.0.13 and 1.2.0 */
+   png_bytep big_row_buf;         /* buffer to save current (unfiltered) row */
+
+#ifdef PNG_READ_QUANTIZE_SUPPORTED
+/* The following three members were added at version 1.0.14 and 1.2.4 */
+   png_bytep quantize_sort;          /* working sort array */
+   png_bytep index_to_palette;       /* where the original index currently is
+                                        in the palette */
+   png_bytep palette_to_index;       /* which original index points to this
+                                         palette color */
+#endif
+
+/* New members added in libpng-1.0.16 and 1.2.6 */
+   png_byte compression_type;
+
+#ifdef PNG_USER_LIMITS_SUPPORTED
+   png_uint_32 user_width_max;
+   png_uint_32 user_height_max;
+
+   /* Added in libpng-1.4.0: Total number of sPLT, text, and unknown
+    * chunks that can be stored (0 means unlimited).
+    */
+   png_uint_32 user_chunk_cache_max;
+
+   /* Total memory that a zTXt, sPLT, iTXt, iCCP, or unknown chunk
+    * can occupy when decompressed.  0 means unlimited.
+    */
+   png_alloc_size_t user_chunk_malloc_max;
+#endif
+
+/* New member added in libpng-1.0.25 and 1.2.17 */
 #ifdef PNG_READ_UNKNOWN_CHUNKS_SUPPORTED
    /* Temporary storage for unknown chunk that the library doesn't recognize,
     * used while reading the chunk.
@@ -377,175 +456,34 @@ struct png_struct_def
    png_unknown_chunk unknown_chunk;
 #endif
 
-#ifdef PNG_SET_UNKNOWN_CHUNKS_SUPPORTED
-   png_bytep    chunk_list;      /* List of png_byte[5]; the textual chunk name
-                                  * followed by a PNG_HANDLE_* byte */
-   int          unknown_default; /* As PNG_HANDLE_* */
-   unsigned int num_chunk_list;  /* Number of entries in the list */
-#endif
-
-   /* USER TRANSFORM SUPPORT */
-#ifdef PNG_READ_USER_TRANSFORM_SUPPORTED
-   png_user_transform_ptr read_user_transform_fn; /* user read transform */
-#endif
-#ifdef PNG_WRITE_USER_TRANSFORM_SUPPORTED
-   png_user_transform_ptr write_user_transform_fn; /* user write transform */
-#endif
-#ifdef PNG_USER_TRANSFORM_PTR_SUPPORTED
-   png_voidp user_transform_ptr;      /* user supplied data for the above */
-   png_byte  user_transform_depth;    /* bit depth of user transformed pixels */
-   png_byte  user_transform_channels; /* channels in user transformed pixels */
-#endif
-
-   /* READ TRANSFORM SUPPORT
-    *
-    * Quite a lot of things can be done to the original image data on read, and
-    * most of these are configurable.  The data required by the configurable
-    * read transforms should be stored here.  The png_color_16 and png_color_8
-    * structures have low alignment requirements and odd sizes, so may cause
-    * misalignment when present.  Member alignment is as follows:
-    *
-    *    png_color_16   png_uint_16
-    *    png_color_8    png_byte
-    */
-   /* GAMMA/BACKGROUND/ALPHA-MODE/RGB-TO-GRAY/tRNS/sBIT
-    *
-    * These things are all interrelated because they need some or all of the
-    * gamma tables.  Some attempt has been made below to order these members by
-    * size, so that as little padding as possible is required.
-    */
-#ifdef PNG_READ_GAMMA_SUPPORTED
-   png_bytep gamma_table;        /* gamma table for 8-bit depth files */
-   png_uint_16p gamma_16_table;  /* gamma table for 16-bit depth files */
-
-#if defined PNG_READ_BACKGROUND_SUPPORTED ||\
-   defined PNG_READ_ALPHA_MODE_SUPPORTED ||\
-   defined PNG_READ_RGB_TO_GRAY_SUPPORTED
-   png_bytep gamma_from_1;       /* converts from 1.0 to screen */
-   png_uint_16p gamma_to_1;      /* converts from file to 1.0 */
-   png_uint_16p gamma_16_from_1; /* converts from 1.0 to screen */
-   png_uint_16p gamma_16_to_1;   /* converts from file to 1.0 */
-#endif /* READ_BACKGROUND || READ_ALPHA_MODE || RGB_TO_GRAY */
-#endif /* PNG_READ_GAMMA_SUPPORTED */
-
-#if defined PNG_READ_tRNS_SUPPORTED || defined PNG_READ_BACKGROUND_SUPPORTED ||\
-   defined PNG_READ_EXPAND_SUPPORTED
-   png_bytep trans_alpha;           /* alpha values for paletted files */
-#endif
-
-   /* Integer values */
-#if defined PNG_READ_BACKGROUND_SUPPORTED ||\
-   defined PNG_READ_ALPHA_MODE_SUPPORTED
-   png_fixed_point background_gamma;
-#endif
-#ifdef PNG_READ_GAMMA_SUPPORTED
-   png_fixed_point screen_gamma; /* screen gamma value (display_exponent) */
-   int gamma_shift; /* number of "insignificant" bits in 16-bit gamma */
-#endif
-
-   /* png_color_16 */
-#if defined PNG_READ_BACKGROUND_SUPPORTED ||\
-   defined PNG_READ_ALPHA_MODE_SUPPORTED
-   png_color_16 background;   /* background color in screen gamma space */
-   png_color_16 background_1; /* background normalized to gamma 1.0 */
-#endif
-#if defined PNG_READ_tRNS_SUPPORTED || defined PNG_READ_BACKGROUND_SUPPORTED ||\
-   defined PNG_READ_EXPAND_SUPPORTED
-   png_color_16 trans_color;  /* transparent color for non-paletted files */
-#endif
-
-   /* png_uint_16 */
-#ifdef PNG_READ_RGB_TO_GRAY_SUPPORTED
-   png_uint_16 rgb_to_gray_red_coeff;
-   png_uint_16 rgb_to_gray_green_coeff;
-   /* The blue coefficient is calculated from the above */
-#endif
-
-   /* png_color_8 */
-#if defined PNG_READ_GAMMA_SUPPORTED || defined PNG_READ_sBIT_SUPPORTED
-   png_color_8 sig_bit;       /* significant bits in each available channel */
-#endif
-
-   /* png_byte */
-#if defined PNG_READ_BACKGROUND_SUPPORTED ||\
-   defined PNG_READ_ALPHA_MODE_SUPPORTED
-   png_byte background_gamma_type;
-#endif
-#ifdef PNG_READ_RGB_TO_GRAY_SUPPORTED
-   png_byte rgb_to_gray_status;
-#endif
-
-   /* SHIFT - both READ_SHIFT and WRITE_SHIFT */
-#if defined PNG_READ_SHIFT_SUPPORTED || defined PNG_WRITE_SHIFT_SUPPORTED
-   png_color_8 shift;         /* shift for significant bit tranformation */
-#endif
-
-   /* FILLER SUPPORT (pixel expansion or read, contraction on write) */
-#if defined PNG_READ_FILLER_SUPPORTED || defined PNG_WRITE_FILLER_SUPPORTED
-   png_uint_16 filler;              /* filler bytes for pixel expansion */
-#endif
-
-   /* QUANTIZE (convert to color-mapped) */
-#ifdef PNG_READ_QUANTIZE_SUPPORTED
-   png_bytep palette_lookup;   /* lookup table for quantizing */
-   png_bytep quantize_index;   /* index translation for palette files */
-   png_bytep quantize_sort;    /* working sort array */
-   png_bytep index_to_palette; /* where the original index currently is in the
-                                * palette
-                                */
-   png_bytep palette_to_index; /* which original index points to this palette
-                                * color
-                                */
-#endif
-
-   /* MNG SUPPORT */
-#ifdef PNG_MNG_FEATURES_SUPPORTED
-   png_uint_32 mng_features_permitted;
-   png_byte filter_type;
-#endif
-
-   /* COMPRESSION AND DECOMPRESSION SUPPORT.
-    *
-    * zlib expects a 'zstream' as the fundamental control structure, it allows
-    * all the parameters to be passed as one pointer.
-    */
-   z_stream    zstream;       /* decompression structure */
+/* New member added in libpng-1.2.26 */
+  png_size_t old_big_row_buf_size;
 
 #ifdef PNG_READ_SUPPORTED
-   /* These, and IDAT_read_size below, control how much input and output (at
-    * most) is available to zlib.
-    */
-   png_uint_32      idat_size;        /* current IDAT size for read */
-   png_alloc_size_t read_buffer_size; /* current size of the buffer */
+/* New member added in libpng-1.2.30 */
+  png_bytep        read_buffer;      /* buffer for reading chunk data */
+  png_alloc_size_t read_buffer_size; /* current size of the buffer */
 #endif
-
-#ifdef PNG_WRITE_CUSTOMIZE_ZTXT_COMPRESSION_SUPPORTED
-   int zlib_text_level;       /* holds zlib compression level */
-   int zlib_text_method;      /* holds zlib compression method */
-   int zlib_text_window_bits; /* holds zlib compression window bits */
-   int zlib_text_mem_level;   /* holds zlib compression memory level */
-   int zlib_text_strategy;    /* holds zlib compression strategy */
-#endif
-
-#ifdef PNG_WRITE_SUPPORTED
-   int zlib_level;            /* holds zlib compression level */
-   int zlib_method;           /* holds zlib compression method */
-   int zlib_window_bits;      /* holds zlib compression window bits */
-   int zlib_mem_level;        /* holds zlib compression memory level */
-   int zlib_strategy;         /* holds zlib compression strategy */
-
-   int zlib_set_level;        /* Actual values set into the zstream on write */
-   int zlib_set_method;
-   int zlib_set_window_bits;
-   int zlib_set_mem_level;
-   int zlib_set_strategy;
-
-   png_compression_bufferp zbuffer_list; /* Created on demand during write */
-   uInt                    zbuffer_size; /* size of the actual zlib buffer */
-#endif
-
 #ifdef PNG_SEQUENTIAL_READ_SUPPORTED
-   uInt IDAT_read_size;       /* limit on read buffer size for IDAT */
+  uInt             IDAT_read_size;   /* limit on read buffer size for IDAT */
+#endif
+
+#ifdef PNG_IO_STATE_SUPPORTED
+/* New member added in libpng-1.4.0 */
+   png_uint_32 io_state;
+#endif
+
+/* New member added in libpng-1.5.6 */
+   png_bytep big_prev_row;
+
+/* New member added in libpng-1.5.7 */
+   void (*read_filter[PNG_FILTER_VALUE_LAST-1])(png_row_infop row_info,
+      png_bytep row, png_const_bytep prev_row);
+
+#ifdef PNG_READ_SUPPORTED
+#if defined(PNG_COLORSPACE_SUPPORTED) || defined(PNG_GAMMA_SUPPORTED)
+   png_colorspace   colorspace;
+#endif
 #endif
 };
 #endif /* PNGSTRUCT_H */

pngtest.c

@@ -1,7 +1,7 @@
 
 /* pngtest.c - a simple test program to test libpng
  *
- * Last changed in libpng 1.7.0 [(PENDING RELEASE)]
+ * Last changed in libpng 1.6.2 [April 25, 2013]
  * Copyright (c) 1998-2013 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.)
@@ -43,8 +43,24 @@
 
 #include "png.h"
 
-#ifdef PNG_READ_SUPPORTED /* else nothing can be done */
-#include PNG_ZLIB_HEADER /* defined by pnglibconf.h */
+/* Known chunks that exist in pngtest.png must be supported or pngtest will fail
+ * simply as a result of re-ordering them.  This may be fixed in 1.7
+ */
+#if defined PNG_READ_SUPPORTED && /* else nothing can be done */\
+   defined PNG_READ_bKGD_SUPPORTED &&\
+   defined PNG_READ_cHRM_SUPPORTED &&\
+   defined PNG_READ_gAMA_SUPPORTED &&\
+   defined PNG_READ_oFFs_SUPPORTED &&\
+   defined PNG_READ_pCAL_SUPPORTED &&\
+   defined PNG_READ_pHYs_SUPPORTED &&\
+   defined PNG_READ_sBIT_SUPPORTED &&\
+   defined PNG_READ_sCAL_SUPPORTED &&\
+   defined PNG_READ_sRGB_SUPPORTED &&\
+   defined PNG_READ_tEXt_SUPPORTED &&\
+   defined PNG_READ_tIME_SUPPORTED &&\
+   defined PNG_READ_zTXt_SUPPORTED
+
+#include "zlib.h"
 /* Copied from pngpriv.h but only used in error messages below. */
 #ifndef PNG_ZBUF_SIZE
 #  define PNG_ZBUF_SIZE 8192
@@ -100,6 +116,10 @@ static int unsupported_chunks = 0; /* chunk unsupported by libpng in input */
 static int error_count = 0; /* count calls to png_error */
 static int warning_count = 0; /* count calls to png_warning */
 
+#ifdef __TURBOC__
+#include <mem.h>
+#endif
+
 /* Define png_jmpbuf() in case we are using a pre-1.0.6 version of libpng */
 #ifndef png_jmpbuf
 #  define png_jmpbuf(png_ptr) png_ptr->jmpbuf
@@ -1169,8 +1189,8 @@ test_one_file(PNG_CONST char *inname, PNG_CONST char *outname)
    }
 #endif
 #ifdef PNG_sCAL_SUPPORTED
-#if defined PNG_FLOATING_POINT_SUPPORTED && \
-   defined PNG_FLOATING_ARITHMETIC_SUPPORTED
+#if defined(PNG_FLOATING_POINT_SUPPORTED) && \
+   defined(PNG_FLOATING_ARITHMETIC_SUPPORTED)
    {
       int unit;
       double scal_width, scal_height;
@@ -1467,7 +1487,8 @@ test_one_file(PNG_CONST char *inname, PNG_CONST char *outname)
 
    /* When the unknown vpAg/sTER chunks are written by pngtest the only way to
     * do it is to write them *before* calling png_write_end.  When unknown
-    * chunks are written by libpng, however, they are written just before IEND.     * There seems to be no way round this, however vpAg/sTER are not expected
+    * chunks are written by libpng, however, they are written just before IEND.
+    * There seems to be no way round this, however vpAg/sTER are not expected
     * after IDAT.
     */
    write_chunks(write_ptr, after_IDAT);
@@ -1941,9 +1962,10 @@ main(void)
 {
    fprintf(STDERR,
       " test ignored because libpng was not built with read support\n");
-   return 0;
+   /* And skip this test */
+   return 77;
 }
 #endif
 
 /* Generate a compiler error if there is an old png.h in the search path. */
-typedef png_libpng_version_1_7_0alpha09 Your_png_h_is_not_version_1_7_0alpha09;
+typedef png_libpng_version_1_6_3beta06 Your_png_h_is_not_version_1_6_3beta06;

pngtrans.c

@@ -1,7 +1,7 @@
 
 /* pngtrans.c - transforms the data in a row (used by both readers and writers)
  *
- * Last changed in libpng 1.7.0 [(PENDING RELEASE)]
+ * Last changed in libpng 1.6.2 [April 25, 2013]
  * Copyright (c) 1998-2013 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.)
@@ -57,9 +57,7 @@ png_set_packing(png_structrp png_ptr)
    if (png_ptr->bit_depth < 8)
    {
       png_ptr->transformations |= PNG_PACK;
-#     ifdef PNG_WRITE_SUPPORTED
-         png_ptr->usr_bit_depth = 8;
-#     endif
+      png_ptr->usr_bit_depth = 8;
    }
 }
 #endif
@@ -784,6 +782,17 @@ png_set_user_transform_info(png_structrp png_ptr, png_voidp
 
    if (png_ptr == NULL)
       return;
+
+#ifdef PNG_READ_USER_TRANSFORM_SUPPORTED
+   if ((png_ptr->mode & PNG_IS_READ_STRUCT) != 0 &&
+      (png_ptr->flags & PNG_FLAG_ROW_INIT) != 0)
+   {
+      png_app_error(png_ptr,
+            "info change after png_start_read_image or png_read_update_info");
+      return;
+   }
+#endif
+
    png_ptr->user_transform_ptr = user_transform_ptr;
    png_ptr->user_transform_depth = (png_byte)user_transform_depth;
    png_ptr->user_transform_channels = (png_byte)user_transform_channels;

pngwio.c

@@ -1,7 +1,7 @@
 
 /* pngwio.c - functions for data output
  *
- * Last changed in libpng 1.7.0 [(PENDING RELEASE)]
+ * Last changed in libpng 1.6.0 [February 14, 2013]
  * Copyright (c) 1998-2013 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.)
@@ -151,7 +151,6 @@ png_set_write_fn(png_structrp png_ptr, png_voidp io_ptr,
 #  endif
 #endif /* PNG_WRITE_FLUSH_SUPPORTED */
 
-#ifdef PNG_READ_SUPPORTED
    /* It is an error to read while writing a png file */
    if (png_ptr->read_data_fn != NULL)
    {
@@ -161,6 +160,5 @@ png_set_write_fn(png_structrp png_ptr, png_voidp io_ptr,
           "Can't set both read_data_fn and write_data_fn in the"
           " same structure");
    }
-#endif
 }
 #endif /* PNG_WRITE_SUPPORTED */

pngwrite.c

@@ -1,7 +1,7 @@
 
 /* pngwrite.c - general routines to write a PNG file
  *
- * Last changed in libpng 1.7.0 [(PENDING RELEASE)]
+ * Last changed in libpng 1.6.2 [April 25, 2013]
  * Copyright (c) 1998-2013 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.)
@@ -12,7 +12,7 @@
  */
 
 #include "pngpriv.h"
-#if defined PNG_SIMPLIFIED_WRITE_SUPPORTED && defined PNG_STDIO_SUPPORTED
+#if defined(PNG_SIMPLIFIED_WRITE_SUPPORTED) && defined(PNG_STDIO_SUPPORTED)
 #  include <errno.h>
 #endif
 
@@ -216,13 +216,8 @@ png_write_info(png_structrp png_ptr, png_const_inforp info_ptr)
       if ((png_ptr->transformations & PNG_INVERT_ALPHA) &&
           info_ptr->color_type == PNG_COLOR_TYPE_PALETTE)
       {
-         int j, jend;
-
-         jend = info_ptr->num_trans;
-         if (jend > PNG_MAX_PALETTE_LENGTH)
-            jend = PNG_MAX_PALETTE_LENGTH;
-
-         for (j = 0; j<jend; ++j)
+         int j;
+         for (j = 0; j<(int)info_ptr->num_trans; j++)
             info_ptr->trans_alpha[j] =
                (png_byte)(255 - info_ptr->trans_alpha[j]);
       }
@@ -499,51 +494,50 @@ png_create_write_struct_2,(png_const_charp user_png_ver, png_voidp error_ptr,
    png_structrp png_ptr = png_create_png_struct(user_png_ver, error_ptr,
       error_fn, warn_fn, mem_ptr, malloc_fn, free_fn);
 #endif /* PNG_USER_MEM_SUPPORTED */
+   if (png_ptr != NULL)
+   {
+      /* Set the zlib control values to defaults; they can be overridden by the
+       * application after the struct has been created.
+       */
+      png_ptr->zbuffer_size = PNG_ZBUF_SIZE;
 
-   /* Set the zlib control values to defaults; they can be overridden by the
-    * application after the struct has been created.
-    */
-   png_ptr->zbuffer_size = PNG_ZBUF_SIZE;
-
-   /* The 'zlib_strategy' setting is irrelevant because png_default_claim in
-    * pngwutil.c defaults it according to whether or not filters will be used,
-    * and ignores this setting.
-    */
-   png_ptr->zlib_strategy = PNG_Z_DEFAULT_STRATEGY;
-   png_ptr->zlib_level = PNG_Z_DEFAULT_COMPRESSION;
-   png_ptr->zlib_mem_level = 8;
-   png_ptr->zlib_window_bits = 15;
-   png_ptr->zlib_method = 8;
+      /* The 'zlib_strategy' setting is irrelevant because png_default_claim in
+       * pngwutil.c defaults it according to whether or not filters will be
+       * used, and ignores this setting.
+       */
+      png_ptr->zlib_strategy = PNG_Z_DEFAULT_STRATEGY;
+      png_ptr->zlib_level = PNG_Z_DEFAULT_COMPRESSION;
+      png_ptr->zlib_mem_level = 8;
+      png_ptr->zlib_window_bits = 15;
+      png_ptr->zlib_method = 8;
 
 #ifdef PNG_WRITE_COMPRESSED_TEXT_SUPPORTED
-   png_ptr->zlib_text_strategy = PNG_TEXT_Z_DEFAULT_STRATEGY;
-   png_ptr->zlib_text_level = PNG_TEXT_Z_DEFAULT_COMPRESSION;
-   png_ptr->zlib_text_mem_level = 8;
-   png_ptr->zlib_text_window_bits = 15;
-   png_ptr->zlib_text_method = 8;
+      png_ptr->zlib_text_strategy = PNG_TEXT_Z_DEFAULT_STRATEGY;
+      png_ptr->zlib_text_level = PNG_TEXT_Z_DEFAULT_COMPRESSION;
+      png_ptr->zlib_text_mem_level = 8;
+      png_ptr->zlib_text_window_bits = 15;
+      png_ptr->zlib_text_method = 8;
 #endif /* PNG_WRITE_COMPRESSED_TEXT_SUPPORTED */
 
-   /* This is a highly dubious configuration option; by default it is off, but
-    * it may be appropriate for private builds that are testing extensions not
-    * conformant to the current specification, or of applications that must not
-    * fail to write at all costs!
-    */
-#  ifdef PNG_BENIGN_WRITE_ERRORS_SUPPORTED
+      /* This is a highly dubious configuration option; by default it is off,
+       * but it may be appropriate for private builds that are testing
+       * extensions not conformant to the current specification, or of
+       * applications that must not fail to write at all costs!
+       */
+#ifdef PNG_BENIGN_WRITE_ERRORS_SUPPORTED
       png_ptr->flags |= PNG_FLAG_BENIGN_ERRORS_WARN;
       /* In stable builds only warn if an application error can be completely
        * handled.
        */
-#  endif
+#endif
 
-   /* App warnings are warnings in release (or release candidate) builds but
-    * are errors during development.
-    */
-#  if PNG_LIBPNG_BUILD_BASE_TYPE >= PNG_LIBPNG_BUILD_RC
+      /* App warnings are warnings in release (or release candidate) builds but
+       * are errors during development.
+       */
+#if PNG_LIBPNG_BUILD_BASE_TYPE >= PNG_LIBPNG_BUILD_RC
       png_ptr->flags |= PNG_FLAG_APP_WARNINGS_WARN;
-#  endif
+#endif
 
-   if (png_ptr != NULL)
-   {
       /* TODO: delay this, it can be done in png_init_io() (if the app doesn't
        * do it itself) avoiding setting the default function if it is not
        * required.
@@ -935,52 +929,42 @@ png_set_filter(png_structrp png_ptr, int method, int filters)
    if ((png_ptr->mng_features_permitted & PNG_FLAG_MNG_FILTER_64) &&
        (method == PNG_INTRAPIXEL_DIFFERENCING))
       method = PNG_FILTER_TYPE_BASE;
+
 #endif
-
-   /* The only supported method, except for the check above, is
-    * PNG_FILTER_TYPE_BASE.  The code below does not use 'method' other than
-    * for the check, so just keep going if png_app_error returns.
-    */
-   if (method != PNG_FILTER_TYPE_BASE)
-      png_app_error(png_ptr, "Unknown custom filter method");
-
-   /* If filter writing is not supported the 'filters' value must be zero,
-    * otherwise the value must be a single, valid, filter value or a set of the
-    * mask values.  The defines in png.h are such that the filter masks used in
-    * this API and internally are 1<<(3+value), value is in the range 0..4, so
-    * this fits in a byte.
-    */
-#  ifdef PNG_WRITE_FILTER_SUPPORTED
-      /* Notice that PNG_NO_FILTERS is 0 and passes this test; this is OK
-       * because filters then gets set to PNG_FILTER_NONE, as is required.
-       */
-      if (filters < PNG_FILTER_VALUE_LAST)
-         filters = 0x08 << filters;
-
-      else if ((filters & ~PNG_ALL_FILTERS) != 0)
+   if (method == PNG_FILTER_TYPE_BASE)
+   {
+      switch (filters & (PNG_ALL_FILTERS | 0x07))
       {
-         png_app_error(png_ptr, "png_set_filter: invalid filters mask/value");
+#ifdef PNG_WRITE_FILTER_SUPPORTED
+         case 5:
+         case 6:
+         case 7: png_app_error(png_ptr, "Unknown row filter for method 0");
+            /* FALL THROUGH */
+#endif /* PNG_WRITE_FILTER_SUPPORTED */
+         case PNG_FILTER_VALUE_NONE:
+            png_ptr->do_filter = PNG_FILTER_NONE; break;
 
-         /* For compatibility with the previous behavior assume a mask value was
-          * passed and ignore the non-mask bits.
-          */
-         filters &= PNG_ALL_FILTERS;
+#ifdef PNG_WRITE_FILTER_SUPPORTED
+         case PNG_FILTER_VALUE_SUB:
+            png_ptr->do_filter = PNG_FILTER_SUB; break;
 
-         /* For a possibly foolish consistency (it shouldn't matter) set
-          * PNG_FILTER_NONE rather than 0.
-          */
-         if (filters == 0)
-            filters = PNG_FILTER_NONE;
+         case PNG_FILTER_VALUE_UP:
+            png_ptr->do_filter = PNG_FILTER_UP; break;
+
+         case PNG_FILTER_VALUE_AVG:
+            png_ptr->do_filter = PNG_FILTER_AVG; break;
+
+         case PNG_FILTER_VALUE_PAETH:
+            png_ptr->do_filter = PNG_FILTER_PAETH; break;
+
+         default:
+            png_ptr->do_filter = (png_byte)filters; break;
+#else
+         default:
+            png_app_error(png_ptr, "Unknown row filter for method 0");
+#endif /* PNG_WRITE_FILTER_SUPPORTED */
       }
-#  else
-      /* PNG_FILTER_VALUE_NONE and PNG_NO_FILTERS are both 0. */
-      if (filters != 0 && filters != PNG_FILTER_NONE)
-         png_app_error(png_ptr, "png_set_filter: no filters supported");
 
-      filters = PNG_FILTER_NONE;
-#  endif
-
-#  ifdef PNG_WRITE_FILTER_SUPPORTED
       /* If we have allocated the row_buf, this means we have already started
        * with the image and we should have allocated all of the filter buffers
        * that have been selected.  If prev_row isn't already allocated, then
@@ -989,45 +973,75 @@ png_set_filter(png_structrp png_ptr, int method, int filters)
        * wants to start and stop using particular filters during compression,
        * it should start out with all of the filters, and then add and
        * remove them after the start of compression.
-       *
-       * NOTE: this is a nasty constraint on the code, because it means that the
-       * prev_row buffer must be maintained even if there are currently no
-       * 'prev_row' requiring filters active.
        */
       if (png_ptr->row_buf != NULL)
       {
-         /* Repeat the checks in png_write_start_row; 1 pixel high or wide
-          * images cannot benefit from certain filters.  If this isn't done here
-          * the check below will fire on 1 pixel high images.
-          */
-         if (png_ptr->height == 1)
-            filters &= ~(PNG_FILTER_UP|PNG_FILTER_AVG|PNG_FILTER_PAETH);
-
-         if (png_ptr->width == 1)
-            filters &= ~(PNG_FILTER_SUB|PNG_FILTER_AVG|PNG_FILTER_PAETH);
-
-         if ((filters & (PNG_FILTER_UP|PNG_FILTER_AVG|PNG_FILTER_PAETH)) != 0
-            && png_ptr->prev_row == NULL)
+#ifdef PNG_WRITE_FILTER_SUPPORTED
+         if ((png_ptr->do_filter & PNG_FILTER_SUB) && png_ptr->sub_row == NULL)
          {
-            /* This is the error case, however it is benign - the previous row
-             * is not available so the filter can't be used.  Just warn here.
-             */
-            png_app_warning(png_ptr,
-               "png_set_filter: UP/AVG/PAETH cannot be added after start");
-            filters &= ~(PNG_FILTER_UP|PNG_FILTER_AVG|PNG_FILTER_PAETH);
+            png_ptr->sub_row = (png_bytep)png_malloc(png_ptr,
+                (png_ptr->rowbytes + 1));
+            png_ptr->sub_row[0] = PNG_FILTER_VALUE_SUB;
          }
 
-         /* Allocate any required buffers that have not already been allocated.
-          */
-         png_write_alloc_filter_row_buffers(png_ptr, filters);
-      }
-#  endif /* PNG_WRITE_FILTER_SUPPORTED */
+         if ((png_ptr->do_filter & PNG_FILTER_UP) && png_ptr->up_row == NULL)
+         {
+            if (png_ptr->prev_row == NULL)
+            {
+               png_warning(png_ptr, "Can't add Up filter after starting");
+               png_ptr->do_filter = (png_byte)(png_ptr->do_filter &
+                   ~PNG_FILTER_UP);
+            }
 
-   /* Finally store the value.
-    * TODO: this field could probably be removed if neither READ nor
-    * WRITE_FILTER are supported.
-    */
-   png_ptr->do_filter = (png_byte)filters; /* SAFE: checked above */
+            else
+            {
+               png_ptr->up_row = (png_bytep)png_malloc(png_ptr,
+                   (png_ptr->rowbytes + 1));
+               png_ptr->up_row[0] = PNG_FILTER_VALUE_UP;
+            }
+         }
+
+         if ((png_ptr->do_filter & PNG_FILTER_AVG) && png_ptr->avg_row == NULL)
+         {
+            if (png_ptr->prev_row == NULL)
+            {
+               png_warning(png_ptr, "Can't add Average filter after starting");
+               png_ptr->do_filter = (png_byte)(png_ptr->do_filter &
+                   ~PNG_FILTER_AVG);
+            }
+
+            else
+            {
+               png_ptr->avg_row = (png_bytep)png_malloc(png_ptr,
+                   (png_ptr->rowbytes + 1));
+               png_ptr->avg_row[0] = PNG_FILTER_VALUE_AVG;
+            }
+         }
+
+         if ((png_ptr->do_filter & PNG_FILTER_PAETH) &&
+             png_ptr->paeth_row == NULL)
+         {
+            if (png_ptr->prev_row == NULL)
+            {
+               png_warning(png_ptr, "Can't add Paeth filter after starting");
+               png_ptr->do_filter &= (png_byte)(~PNG_FILTER_PAETH);
+            }
+
+            else
+            {
+               png_ptr->paeth_row = (png_bytep)png_malloc(png_ptr,
+                   (png_ptr->rowbytes + 1));
+               png_ptr->paeth_row[0] = PNG_FILTER_VALUE_PAETH;
+            }
+         }
+
+         if (png_ptr->do_filter == PNG_NO_FILTERS)
+#endif /* PNG_WRITE_FILTER_SUPPORTED */
+            png_ptr->do_filter = PNG_FILTER_NONE;
+      }
+   }
+   else
+      png_error(png_ptr, "Unknown custom filter method");
 }
 
 /* This allows us to influence the way in which libpng chooses the "best"

pngwtran.c

@@ -1,7 +1,7 @@
 
 /* pngwtran.c - transforms the data in a row for PNG writers
  *
- * Last changed in libpng 1.7.0 [(PENDING RELEASE)]
+ * Last changed in libpng 1.6.0 [February 14, 2013]
  * Copyright (c) 1998-2013 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.)

pngwutil.c

@@ -1,7 +1,7 @@
 
 /* pngwutil.c - utilities to write a PNG file
  *
- * Last changed in libpng 1.7.0 [(PENDING RELEASE)]
+ * Last changed in libpng 1.6.2 [April 25, 2013]
  * Copyright (c) 1998-2013 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.)
@@ -1425,11 +1425,10 @@ png_write_tRNS(png_structrp png_ptr, png_const_bytep trans_alpha,
 
    if (color_type == PNG_COLOR_TYPE_PALETTE)
    {
-      if (num_trans <= 0 || num_trans > png_ptr->num_palette)
+      if (num_trans <= 0 || num_trans > (int)png_ptr->num_palette)
       {
-         /* This is an error which can only be reliably detected late. */
-         png_app_error(png_ptr,
-            "Invalid number of transparent colors specified");
+         png_app_warning(png_ptr,
+             "Invalid number of transparent colors specified");
          return;
       }
 
@@ -1443,8 +1442,7 @@ png_write_tRNS(png_structrp png_ptr, png_const_bytep trans_alpha,
       /* One 16 bit value */
       if (tran->gray >= (1 << png_ptr->bit_depth))
       {
-         /* This can no longer happen because it is checked in png_set_tRNS */
-         png_app_error(png_ptr,
+         png_app_warning(png_ptr,
              "Ignoring attempt to write tRNS chunk out-of-range for bit_depth");
 
          return;
@@ -1466,8 +1464,7 @@ png_write_tRNS(png_structrp png_ptr, png_const_bytep trans_alpha,
       if (buf[0] | buf[2] | buf[4])
 #endif
       {
-         /* Also checked in png_set_tRNS */
-         png_app_error(png_ptr,
+         png_app_warning(png_ptr,
            "Ignoring attempt to write 16-bit tRNS chunk when bit_depth is 8");
          return;
       }
@@ -1477,8 +1474,7 @@ png_write_tRNS(png_structrp png_ptr, png_const_bytep trans_alpha,
 
    else
    {
-      /* Checked in png_set_tRNS */
-      png_app_error(png_ptr, "Can't write tRNS with an alpha channel");
+      png_app_warning(png_ptr, "Can't write tRNS with an alpha channel");
    }
 }
 #endif
@@ -1748,6 +1744,9 @@ png_write_iTXt(png_structrp png_ptr, int compression, png_const_charp key,
    {
       if (comp.input_len > PNG_UINT_31_MAX-prefix_len)
          png_error(png_ptr, "iTXt: uncompressed text too long");
+
+      /* So the string will fit in a chunk: */
+      comp.output_len = (png_uint_32)/*SAFE*/comp.input_len;
    }
 
    png_write_chunk_header(png_ptr, png_iTXt, comp.output_len + prefix_len);
@@ -1935,47 +1934,6 @@ png_write_tIME(png_structrp png_ptr, png_const_timep mod_time)
 }
 #endif
 
-#ifdef PNG_WRITE_FILTER_SUPPORTED
-void /* PRIVATE */
-png_write_alloc_filter_row_buffers(png_structrp png_ptr, int filters)
-   /* Allocate row buffers for any filters that need them, this is also called
-    * from png_set_filter if the filters are changed during write to ensure that
-    * the required buffers exist.  png_set_filter ensures that up/avg/paeth are
-    * only set if png_ptr->prev_row is allocated.
-    */
-{
-   /* The buffer size is determined just by the output row size, not any
-    * processing requirements.
-    */
-   png_alloc_size_t buf_size = png_ptr->rowbytes + 1;
-
-   if ((filters & PNG_FILTER_SUB) != 0 && png_ptr->sub_row == NULL)
-   {
-      png_ptr->sub_row = png_voidcast(png_bytep, png_malloc(png_ptr, buf_size));
-      png_ptr->sub_row[0] = PNG_FILTER_VALUE_SUB;
-   }
-
-   if ((filters & PNG_FILTER_UP) != 0 && png_ptr->up_row == NULL)
-   {
-      png_ptr->up_row = png_voidcast(png_bytep, png_malloc(png_ptr, buf_size));
-      png_ptr->up_row[0] = PNG_FILTER_VALUE_UP;
-   }
-
-   if ((filters & PNG_FILTER_AVG) != 0 && png_ptr->avg_row == NULL)
-   {
-      png_ptr->avg_row = png_voidcast(png_bytep, png_malloc(png_ptr, buf_size));
-      png_ptr->avg_row[0] = PNG_FILTER_VALUE_AVG;
-   }
-
-   if ((filters & PNG_FILTER_PAETH) != 0 && png_ptr->paeth_row == NULL)
-   {
-      png_ptr->paeth_row = png_voidcast(png_bytep, png_malloc(png_ptr,
-         buf_size));
-      png_ptr->paeth_row[0] = PNG_FILTER_VALUE_PAETH;
-   }
-}
-#endif /* PNG_WRITE_FILTER_SUPPORTED */
-
 /* Initializes the row writing capability of libpng */
 void /* PRIVATE */
 png_write_start_row(png_structrp png_ptr)
@@ -1996,18 +1954,11 @@ png_write_start_row(png_structrp png_ptr)
    static PNG_CONST png_byte png_pass_yinc[7] = {8, 8, 8, 4, 4, 2, 2};
 #endif
 
-#ifdef PNG_WRITE_FILTER_SUPPORTED
-   int filters;
-#endif
-
    png_alloc_size_t buf_size;
    int usr_pixel_depth;
 
    png_debug(1, "in png_write_start_row");
 
-   if (png_ptr == NULL)
-      return;
-
    usr_pixel_depth = png_ptr->usr_channels * png_ptr->usr_bit_depth;
    buf_size = PNG_ROWBYTES(usr_pixel_depth, png_ptr->width) + 1;
 
@@ -2016,34 +1967,49 @@ png_write_start_row(png_structrp png_ptr)
    png_ptr->maximum_pixel_depth = (png_byte)usr_pixel_depth;
 
    /* Set up row buffer */
-   png_ptr->row_buf = png_voidcast(png_bytep, png_malloc(png_ptr, buf_size));
+   png_ptr->row_buf = (png_bytep)png_malloc(png_ptr, buf_size);
 
    png_ptr->row_buf[0] = PNG_FILTER_VALUE_NONE;
 
 #ifdef PNG_WRITE_FILTER_SUPPORTED
-   filters = png_ptr->do_filter;
+   /* Set up filtering buffer, if using this filter */
+   if (png_ptr->do_filter & PNG_FILTER_SUB)
+   {
+      png_ptr->sub_row = (png_bytep)png_malloc(png_ptr, png_ptr->rowbytes + 1);
 
-   if (png_ptr->height == 1)
-      filters &= ~(PNG_FILTER_UP|PNG_FILTER_AVG|PNG_FILTER_PAETH);
+      png_ptr->sub_row[0] = PNG_FILTER_VALUE_SUB;
+   }
 
-   if (png_ptr->width == 1)
-      filters &= ~(PNG_FILTER_SUB|PNG_FILTER_AVG|PNG_FILTER_PAETH);
+   /* We only need to keep the previous row if we are using one of these. */
+   if (png_ptr->do_filter & (PNG_FILTER_AVG | PNG_FILTER_UP | PNG_FILTER_PAETH))
+   {
+      /* Set up previous row buffer */
+      png_ptr->prev_row = (png_bytep)png_calloc(png_ptr, buf_size);
 
-   if (filters == 0)
-      filters = PNG_FILTER_NONE;
+      if (png_ptr->do_filter & PNG_FILTER_UP)
+      {
+         png_ptr->up_row = (png_bytep)png_malloc(png_ptr,
+            png_ptr->rowbytes + 1);
 
-   /* We only need to keep the previous row if we are using one of the following
-    * filters.
-    */
-   if (filters & (PNG_FILTER_AVG | PNG_FILTER_UP | PNG_FILTER_PAETH))
-      png_ptr->prev_row = png_voidcast(png_bytep, png_calloc(png_ptr,
-         buf_size));
+         png_ptr->up_row[0] = PNG_FILTER_VALUE_UP;
+      }
 
-   png_write_alloc_filter_row_buffers(png_ptr, filters);
+      if (png_ptr->do_filter & PNG_FILTER_AVG)
+      {
+         png_ptr->avg_row = (png_bytep)png_malloc(png_ptr,
+             png_ptr->rowbytes + 1);
 
-   png_ptr->do_filter = (png_byte)filters; /* in case it was changed above */
-#else
-   png_ptr->do_filter = PNG_FILTER_NONE;
+         png_ptr->avg_row[0] = PNG_FILTER_VALUE_AVG;
+      }
+
+      if (png_ptr->do_filter & PNG_FILTER_PAETH)
+      {
+         png_ptr->paeth_row = (png_bytep)png_malloc(png_ptr,
+             png_ptr->rowbytes + 1);
+
+         png_ptr->paeth_row[0] = PNG_FILTER_VALUE_PAETH;
+      }
+   }
 #endif /* PNG_WRITE_FILTER_SUPPORTED */
 
 #ifdef PNG_WRITE_INTERLACING_SUPPORTED
@@ -3031,7 +2997,6 @@ png_write_filtered_row(png_structrp png_ptr, png_bytep filtered_row,
 
    png_compress_IDAT(png_ptr, filtered_row, full_row_length, Z_NO_FLUSH);
 
-#ifdef PNG_WRITE_FILTER_SUPPORTED
    /* Swap the current and previous rows */
    if (png_ptr->prev_row != NULL)
    {
@@ -3041,7 +3006,6 @@ png_write_filtered_row(png_structrp png_ptr, png_bytep filtered_row,
       png_ptr->prev_row = png_ptr->row_buf;
       png_ptr->row_buf = tptr;
    }
-#endif /* PNG_WRITE_FILTER_SUPPORTED */
 
    /* Finish row - updates counters and flushes zlib if last row */
    png_write_finish_row(png_ptr);

projects/visualc71/libpng.vcproj

@@ -30,7 +30,7 @@
 				Name="VCCustomBuildTool"/>
 			<Tool
 				Name="VCLinkerTool"
-				OutputFile="$(OutDir)/libpng17.dll"
+				OutputFile="$(OutDir)/libpng16.dll"
 				LinkIncremental="1"/>
 			<Tool
 				Name="VCMIDLTool"/>
@@ -78,7 +78,7 @@
 				Name="VCCustomBuildTool"/>
 			<Tool
 				Name="VCLinkerTool"
-				OutputFile="$(OutDir)/libpng17d.dll"
+				OutputFile="$(OutDir)/libpng16d.dll"
 				GenerateDebugInformation="TRUE"/>
 			<Tool
 				Name="VCMIDLTool"/>
@@ -126,7 +126,7 @@
 				Name="VCCustomBuildTool"/>
 			<Tool
 				Name="VCLinkerTool"
-				OutputFile="$(OutDir)/libpng17vb.dll"
+				OutputFile="$(OutDir)/libpng16vb.dll"
 				LinkIncremental="1"/>
 			<Tool
 				Name="VCMIDLTool"/>

projects/visualc71/pngtest.vcproj

@@ -130,7 +130,7 @@ $(TargetPath) ..\..\pngtest.png $(IntDir)\pngout.png"
 				Name="VCLinkerTool"
 				OutputFile="$(OutDir)/pngtest.exe"
 				LinkIncremental="1"
-				IgnoreDefaultLibraryNames="$(IntDir)\libpng17b.lib"
+				IgnoreDefaultLibraryNames="$(IntDir)\libpng16b.lib"
 				SubSystem="1"
 				TargetMachine="1"/>
 			<Tool

projects/vstudio/libpng/libpng.vcxproj

@@ -63,23 +63,23 @@
     <LinkIncremental>false</LinkIncremental>
     <CustomBuildBeforeTargets>
     </CustomBuildBeforeTargets>
-    <TargetName>$(ProjectName)17</TargetName>
+    <TargetName>$(ProjectName)16</TargetName>
   </PropertyGroup>
   <PropertyGroup Condition="'$(Configuration)|$(Platform)'=='Debug Library|Win32'">
     <LinkIncremental>false</LinkIncremental>
     <CustomBuildBeforeTargets />
-    <TargetName>$(ProjectName)17</TargetName>
+    <TargetName>$(ProjectName)16</TargetName>
   </PropertyGroup>
   <PropertyGroup Condition="'$(Configuration)|$(Platform)'=='Release|Win32'">
     <LinkIncremental>false</LinkIncremental>
     <CustomBuildBeforeTargets>
     </CustomBuildBeforeTargets>
-    <TargetName>$(ProjectName)17</TargetName>
+    <TargetName>$(ProjectName)16</TargetName>
   </PropertyGroup>
   <PropertyGroup Condition="'$(Configuration)|$(Platform)'=='Release Library|Win32'">
     <LinkIncremental>false</LinkIncremental>
     <CustomBuildBeforeTargets />
-    <TargetName>$(ProjectName)17</TargetName>
+    <TargetName>$(ProjectName)16</TargetName>
   </PropertyGroup>
   <ItemDefinitionGroup Condition="'$(Configuration)|$(Platform)'=='Debug|Win32'">
     <ClCompile>
@@ -107,7 +107,7 @@
       <SubSystem>Windows</SubSystem>
       <GenerateDebugInformation>true</GenerateDebugInformation>
       <AdditionalDependencies>zlib.lib</AdditionalDependencies>
-      <Version>17</Version>
+      <Version>16</Version>
       <AdditionalLibraryDirectories>$(OutDir)</AdditionalLibraryDirectories>
     </Link>
   </ItemDefinitionGroup>
@@ -164,7 +164,7 @@
       <EnableCOMDATFolding>true</EnableCOMDATFolding>
       <OptimizeReferences>true</OptimizeReferences>
       <AdditionalDependencies>zlib.lib</AdditionalDependencies>
-      <Version>17</Version>
+      <Version>16</Version>
       <AdditionalLibraryDirectories>$(OutDir)</AdditionalLibraryDirectories>
     </Link>
   </ItemDefinitionGroup>

projects/vstudio/pngstest/pngstest.vcxproj

@@ -96,7 +96,7 @@
     <Link>
       <SubSystem>Console</SubSystem>
       <GenerateDebugInformation>true</GenerateDebugInformation>
-      <AdditionalDependencies>libpng17.lib</AdditionalDependencies>
+      <AdditionalDependencies>libpng16.lib</AdditionalDependencies>
       <AdditionalLibraryDirectories>$(OutDir)</AdditionalLibraryDirectories>
     </Link>
     <CustomBuildStep>
@@ -129,7 +129,7 @@
     <Link>
       <SubSystem>Console</SubSystem>
       <GenerateDebugInformation>true</GenerateDebugInformation>
-      <AdditionalDependencies>libpng17.lib;zlib.lib</AdditionalDependencies>
+      <AdditionalDependencies>libpng16.lib;zlib.lib</AdditionalDependencies>
       <AdditionalLibraryDirectories>$(OutDir)</AdditionalLibraryDirectories>
     </Link>
     <CustomBuildStep>
@@ -163,7 +163,7 @@
       <GenerateDebugInformation>true</GenerateDebugInformation>
       <EnableCOMDATFolding>true</EnableCOMDATFolding>
       <OptimizeReferences>true</OptimizeReferences>
-      <AdditionalDependencies>libpng17.lib</AdditionalDependencies>
+      <AdditionalDependencies>libpng16.lib</AdditionalDependencies>
       <AdditionalLibraryDirectories>$(OutDir)</AdditionalLibraryDirectories>
       <LinkTimeCodeGeneration>UseLinkTimeCodeGeneration</LinkTimeCodeGeneration>
     </Link>
@@ -199,7 +199,7 @@
       <GenerateDebugInformation>true</GenerateDebugInformation>
       <EnableCOMDATFolding>true</EnableCOMDATFolding>
       <OptimizeReferences>true</OptimizeReferences>
-      <AdditionalDependencies>libpng17.lib;zlib.lib</AdditionalDependencies>
+      <AdditionalDependencies>libpng16.lib;zlib.lib</AdditionalDependencies>
       <AdditionalLibraryDirectories>$(OutDir)</AdditionalLibraryDirectories>
       <LinkTimeCodeGeneration>UseLinkTimeCodeGeneration</LinkTimeCodeGeneration>
     </Link>

projects/vstudio/pngtest/pngtest.vcxproj

@@ -96,7 +96,7 @@
     <Link>
       <SubSystem>Console</SubSystem>
       <GenerateDebugInformation>true</GenerateDebugInformation>
-      <AdditionalDependencies>libpng17.lib</AdditionalDependencies>
+      <AdditionalDependencies>libpng16.lib</AdditionalDependencies>
       <AdditionalLibraryDirectories>$(OutDir)</AdditionalLibraryDirectories>
     </Link>
     <CustomBuildStep>
@@ -129,7 +129,7 @@
     <Link>
       <SubSystem>Console</SubSystem>
       <GenerateDebugInformation>true</GenerateDebugInformation>
-      <AdditionalDependencies>libpng17.lib;zlib.lib</AdditionalDependencies>
+      <AdditionalDependencies>libpng16.lib;zlib.lib</AdditionalDependencies>
       <AdditionalLibraryDirectories>$(OutDir)</AdditionalLibraryDirectories>
     </Link>
     <CustomBuildStep>
@@ -164,7 +164,7 @@
       <EnableCOMDATFolding>true</EnableCOMDATFolding>
       <OptimizeReferences>true</OptimizeReferences>
       <LinkTimeCodeGeneration>UseLinkTimeCodeGeneration</LinkTimeCodeGeneration>
-      <AdditionalDependencies>libpng17.lib</AdditionalDependencies>
+      <AdditionalDependencies>libpng16.lib</AdditionalDependencies>
       <AdditionalLibraryDirectories>$(OutDir)</AdditionalLibraryDirectories>
     </Link>
     <CustomBuildStep>
@@ -199,7 +199,7 @@
       <GenerateDebugInformation>true</GenerateDebugInformation>
       <EnableCOMDATFolding>true</EnableCOMDATFolding>
       <OptimizeReferences>true</OptimizeReferences>
-      <AdditionalDependencies>libpng17.lib;zlib.lib</AdditionalDependencies>
+      <AdditionalDependencies>libpng16.lib;zlib.lib</AdditionalDependencies>
       <LinkTimeCodeGeneration>UseLinkTimeCodeGeneration</LinkTimeCodeGeneration>
       <AdditionalLibraryDirectories>$(OutDir)</AdditionalLibraryDirectories>
     </Link>

projects/vstudio/pngunknown/pngunknown.vcxproj

@@ -96,7 +96,7 @@
     <Link>
       <SubSystem>Console</SubSystem>
       <GenerateDebugInformation>true</GenerateDebugInformation>
-      <AdditionalDependencies>libpng17.lib</AdditionalDependencies>
+      <AdditionalDependencies>libpng16.lib</AdditionalDependencies>
       <AdditionalLibraryDirectories>$(OutDir)</AdditionalLibraryDirectories>
     </Link>
     <CustomBuildStep>
@@ -129,7 +129,7 @@
     <Link>
       <SubSystem>Console</SubSystem>
       <GenerateDebugInformation>true</GenerateDebugInformation>
-      <AdditionalDependencies>libpng17.lib;zlib.lib</AdditionalDependencies>
+      <AdditionalDependencies>libpng16.lib;zlib.lib</AdditionalDependencies>
       <AdditionalLibraryDirectories>$(OutDir)</AdditionalLibraryDirectories>
     </Link>
     <CustomBuildStep>
@@ -163,7 +163,7 @@
       <GenerateDebugInformation>true</GenerateDebugInformation>
       <EnableCOMDATFolding>true</EnableCOMDATFolding>
       <OptimizeReferences>true</OptimizeReferences>
-      <AdditionalDependencies>libpng17.lib</AdditionalDependencies>
+      <AdditionalDependencies>libpng16.lib</AdditionalDependencies>
       <AdditionalLibraryDirectories>$(OutDir)</AdditionalLibraryDirectories>
       <LinkTimeCodeGeneration>UseLinkTimeCodeGeneration</LinkTimeCodeGeneration>
     </Link>
@@ -199,7 +199,7 @@
       <GenerateDebugInformation>true</GenerateDebugInformation>
       <EnableCOMDATFolding>true</EnableCOMDATFolding>
       <OptimizeReferences>true</OptimizeReferences>
-      <AdditionalDependencies>libpng17.lib;zlib.lib</AdditionalDependencies>
+      <AdditionalDependencies>libpng16.lib;zlib.lib</AdditionalDependencies>
       <AdditionalLibraryDirectories>$(OutDir)</AdditionalLibraryDirectories>
       <LinkTimeCodeGeneration>UseLinkTimeCodeGeneration</LinkTimeCodeGeneration>
     </Link>

projects/vstudio/pngvalid/pngvalid.vcxproj

@@ -96,7 +96,7 @@
     <Link>
       <SubSystem>Console</SubSystem>
       <GenerateDebugInformation>true</GenerateDebugInformation>
-      <AdditionalDependencies>libpng17.lib;zlib.lib</AdditionalDependencies>
+      <AdditionalDependencies>libpng16.lib;zlib.lib</AdditionalDependencies>
       <AdditionalLibraryDirectories>$(OutDir)</AdditionalLibraryDirectories>
     </Link>
     <CustomBuildStep>
@@ -129,7 +129,7 @@
     <Link>
       <SubSystem>Console</SubSystem>
       <GenerateDebugInformation>true</GenerateDebugInformation>
-      <AdditionalDependencies>libpng17.lib;zlib.lib</AdditionalDependencies>
+      <AdditionalDependencies>libpng16.lib;zlib.lib</AdditionalDependencies>
       <AdditionalLibraryDirectories>$(OutDir)</AdditionalLibraryDirectories>
     </Link>
     <CustomBuildStep>
@@ -163,7 +163,7 @@
       <GenerateDebugInformation>true</GenerateDebugInformation>
       <EnableCOMDATFolding>true</EnableCOMDATFolding>
       <OptimizeReferences>true</OptimizeReferences>
-      <AdditionalDependencies>libpng17.lib;zlib.lib</AdditionalDependencies>
+      <AdditionalDependencies>libpng16.lib;zlib.lib</AdditionalDependencies>
       <AdditionalLibraryDirectories>$(OutDir)</AdditionalLibraryDirectories>
       <LinkTimeCodeGeneration>UseLinkTimeCodeGeneration</LinkTimeCodeGeneration>
     </Link>
@@ -199,7 +199,7 @@
       <GenerateDebugInformation>true</GenerateDebugInformation>
       <EnableCOMDATFolding>true</EnableCOMDATFolding>
       <OptimizeReferences>true</OptimizeReferences>
-      <AdditionalDependencies>libpng17.lib;zlib.lib</AdditionalDependencies>
+      <AdditionalDependencies>libpng16.lib;zlib.lib</AdditionalDependencies>
       <AdditionalLibraryDirectories>$(OutDir)</AdditionalLibraryDirectories>
       <LinkTimeCodeGeneration>UseLinkTimeCodeGeneration</LinkTimeCodeGeneration>
     </Link>

projects/vstudio/readme.txt

@@ -1,7 +1,7 @@
 
 VisualStudio instructions
 
-libpng version 1.7.0alpha09 - January 21, 2013
+libpng version 1.6.3beta06 - May 12, 2013
 
 Copyright (c) 1998-2010 Glenn Randers-Pehrson
 
@@ -40,7 +40,7 @@ problems.
 
 If you don't use the Visual Studio defaults your application must still be built
 with the default runtime option (/MD).  If, for some reason, it is not then your
-application will crash inside libpng17.dll as soon as libpng tries to read
+application will crash inside libpng16.dll as soon as libpng tries to read
 from a file handle you pass in.
 
 If you do not want to use the DLL, for example for a very small application,

projects/vstudio/zlib.props

@@ -2,7 +2,7 @@
 <!--
  * zlib.props - location of zlib source
  *
- * libpng version 1.7.0alpha09 - January 21, 2013
+ * libpng version 1.6.3beta06 - May 12, 2013
  *
  * Copyright (c) 1998-2011 Glenn Randers-Pehrson
  *

scripts/README.txt

@@ -1,9 +1,9 @@
 
-Makefiles for  libpng version 1.7.0alpha09 - January 21, 2013
+Makefiles for  libpng version 1.6.3beta06 - May 12, 2013
 
 pnglibconf.h.prebuilt       =>  Stores configuration settings
  makefile.linux    =>  Linux/ELF makefile
-                       (gcc, creates libpng17.so.17.1.7.0alpha09)
+                       (gcc, creates libpng16.so.16.1.6.3beta06)
  makefile.gcc      =>  Generic makefile (gcc, creates static libpng.a)
  makefile.knr      =>  Archaic UNIX Makefile that converts files with
                        ansi2knr (Requires ansi2knr.c from
@@ -20,7 +20,7 @@ pnglibconf.h.prebuilt       =>  Stores configuration settings
  makefile.dec      =>  DEC Alpha UNIX makefile
  makefile.dj2      =>  DJGPP 2 makefile
  makefile.elf      =>  Linux/ELF makefile symbol versioning,
-                       (gcc, creates libpng17.so.17.1.7.0alpha09)
+                       (gcc, creates libpng16.so.16.1.6.3beta06)
  makefile.freebsd  =>  FreeBSD makefile
  makefile.gcc      =>  Generic gcc makefile
  makefile.hpgcc    =>  HPUX makefile using gcc
@@ -35,12 +35,12 @@ pnglibconf.h.prebuilt       =>  Stores configuration settings
  makefile.os2      =>  OS/2 Makefile (gcc and emx, requires libpng.def)
  makefile.sco      =>  For SCO OSr5  ELF and Unixware 7 with Native cc
  makefile.sggcc    =>  Silicon Graphics (gcc,
-                       creates libpng17.so.17.1.7.0alpha09)
+                       creates libpng16.so.16.1.6.3beta06)
  makefile.sgi      =>  Silicon Graphics IRIX makefile (cc, creates static lib)
  makefile.solaris  =>  Solaris 2.X makefile (gcc,
-                       creates libpng17.so.17.1.7.0alpha09)
+                       creates libpng16.so.16.1.6.3beta06)
  makefile.so9      =>  Solaris 9 makefile (gcc,
-                       creates libpng17.so.17.1.7.0alpha09)
+                       creates libpng16.so.16.1.6.3beta06)
  makefile.std      =>  Generic UNIX makefile (cc, creates static libpng.a)
  makefile.sunos    =>  Sun makefile
  makefile.32sunu   =>  Sun Ultra 32-bit makefile

scripts/checksym.awk

@@ -113,6 +113,16 @@ END{
       err = 1
    }
    unexported=0
+   # Add a standard header to symbols.new:
+   print ";Version INSERT-VERSION-HERE" >of
+   print ";--------------------------------------------------------------" >of
+   print "; LIBPNG symbol list as a Win32 DEF file" >of
+   print "; Contains all the symbols that can be exported from libpng" >of
+   print ";--------------------------------------------------------------" >of
+   print "LIBRARY" >of
+   print "" >of
+   print "EXPORTS" >of
+
    for (o=1; o<=lasto; ++o) {
       if (symbol[o] == "" && removed[o] == "") {
          if (unexported == 0) unexported = o

scripts/def.dfn

@@ -8,31 +8,22 @@
  * and license in png.h
  */
 
-/* These macros exist to make the header and trailer shorter below: */
-#define S PNG_DEFN_MAGIC
-#define E PNG_DEFN_END
-
 /* Write the export file header: */
-S-;---------------------------------------------------------------E
-S-; LIBPNG module definition file for OS/2-E
-S-;---------------------------------------------------------------E
-S--E
-S-; If you give the library an explicit name one or other files-E
-S-; may need modifying to support the new name on one or more-E
-S-; systems.-E
-S-LIBRARY-E
-S-OS2 DESCRIPTION "PNG image compression library"-E
-S-OS2 CODE PRELOAD MOVEABLE DISCARDABLE-E
-S--E
-S-EXPORTS-E
-S-;Version libpng 1. PNG_JOIN 7. PNG_JOIN 0-E
+PNG_DFN ";--------------------------------------------------------------"
+PNG_DFN "; LIBPNG module definition file for OS/2"
+PNG_DFN ";--------------------------------------------------------------"
+PNG_DFN ""
+PNG_DFN "; If you give the library an explicit name one or other files"
+PNG_DFN "; may need modifying to support the new name on one or more"
+PNG_DFN "; systems."
+PNG_DFN "LIBRARY"
+PNG_DFN "OS2 DESCRIPTION "PNG image compression library""
+PNG_DFN "OS2 CODE PRELOAD MOVEABLE DISCARDABLE"
+PNG_DFN ""
+PNG_DFN "EXPORTS"
+PNG_DFN ";Version 1.6.3beta06"
 
-/* NOTE: PNG_JOIN is interpreted by the calling script as a signal to
- * join the two things on either side, so we can do symbol
- * substitution within the name, regular C ## joins the pp-tokens,
- * not their final values.
- */
 #define PNG_EXPORTA(ordinal, type, name, args, attributes)\
-	PNG_DEFN_MAGIC- SYMBOL_PREFIX PNG_JOIN name-PNG_DEFN_END
+        PNG_DFN "@" SYMBOL_PREFIX "@@" name "@"
 
 #include "../png.h"

scripts/dfn.awk

@@ -0,0 +1,203 @@
+#!/bin/awk -f
+# scripts/dfn.awk - process a .dfn file
+#
+# last changed in libpng version 1.5.14 - February 4, 2013
+#
+# Copyright (c) 2013-2013 Glenn Randers-Pehrson
+#
+# This code is released under the libpng license.
+# For conditions of distribution and use, see the disclaimer
+# and license in png.h
+
+# The output of this script is written to the file given by
+# the variable 'out', which should be set on the command line.
+# Error messages are printed to stdout and if any are printed
+# the script will exit with error code 1.
+
+BEGIN{
+   out="/dev/null"       # as a flag
+   out_count=0           # count of output lines
+   err=0                 # set if an error occured
+   sort=0                # sort the output
+   array[""]=""
+}
+
+# The output file must be specified before any input:
+NR==1 && out == "/dev/null" {
+   print "out=output.file must be given on the command line"
+   # but continue without setting the error code, this allows the
+   # script to be checked easily
+}
+
+# Output can be sorted; two lines are recognized
+$1 == "PNG_DFN_START_SORT"{
+   sort=0+$2
+   next
+}
+
+$1 ~ /^PNG_DFN_END_SORT/{
+   # Do a very simple, slow, sort; notice that blank lines won't be
+   # output by this
+   for (entry in array) {
+      while (array[entry] != "") {
+         key = entry
+         value = array[key]
+         array[key] = ""
+
+         for (alt in array) {
+            if (array[alt] != "" && alt < key) {
+               array[key] = value
+               value = array[alt]
+               key = alt
+               array[alt] = ""
+            }
+         }
+
+         print value >out
+      }
+   }
+   sort=0
+   next
+}
+
+/^[^"]*PNG_DFN *".*"[^"]*$/{
+   # A definition line, apparently correctly formated, extract the
+   # definition then replace any doubled "" that remain with a single
+   # double quote.  Notice that the original doubled double quotes
+   # may have been split by tokenization
+   #
+   # Sometimes GCC splits the PNG_DFN lines, we know this has happened
+   # if the quotes aren't closed and must read another line.  In this
+   # case it is essential to reject lines that start '#' because those
+   # are introduced #line directives.
+   orig=$0
+   line=$0
+   lineno=FNR
+   if (lineno == "") lineno=NR
+
+   if (sub(/^[^"]*PNG_DFN *"/,"",line) != 1) {
+	print "line", lineno ": processing failed:"
+	print orig
+	err=1
+       next
+   } else {
+	++out_count
+   }
+
+   # Now examine quotes within the value:
+   #
+   #   @" - delete this and any following spaces
+   #   "@ - delete this and any preceding spaces
+   #   @' - replace this by a double quote
+   #
+   # This allows macro substitution by the C compiler thus:
+   #
+   #   #define first_name John
+   #   #define last_name Smith
+   #
+   #	PNG_DFN"#define name @'@" first_name "@ @" last_name "@@'"
+   #
+   # Might get C preprocessed to:
+   #
+   #   PNG_DFN "#define foo @'@" John "@ @" Smith "@@'"
+   #
+   # Which this script reduces to:
+   #
+   #	#define name "John Smith"
+   #
+   while (1) {
+      # While there is an @" remove it and the next "@
+      if (line ~ /@"/) {
+         if (line ~ /@".*"@/) {
+            # Do this special case first to avoid swallowing extra spaces
+            # before or after the @ stuff:
+            if (!sub(/@" *"@/, "", line)) {
+               # Ok, do it in pieces - there has to be a non-space between the
+               # two.  NOTE: really weird things happen if a leading @" is
+               # lost - the code will error out below (I believe).
+               if (!sub(/@" */, "", line) || !sub(/ *"@/, "", line)) {
+                  print "line", lineno, ": internal error:", orig
+                  exit 1
+               }
+            }
+         }
+
+         # There is no matching "@.  Assume a split line
+         else while (1) {
+            if (getline nextline) {
+               # If the line starts with '#' it is a preprocesor line directive
+               # from cc -E, skip it:
+               if (nextline !~ /^#/) {
+                  line = line " " nextline
+                  break
+               }
+            } else {
+               # This is end-of-input - probably a missig "@ on the first line:
+               print "line", lineno ": unbalanced @\" ... \"@ pair"
+               err=1
+               next
+            }
+         }
+
+         # Keep going until all the @" have gone
+         continue
+      }
+
+      # Attempt to remove a trailing " (not preceded by '@') - if this can
+      # be done stop now, if not assume a split line again
+      if (sub(/"[^"]*$/, "", line))
+         break
+
+      # Read another line
+      while (1) {
+         if (getline nextline) {
+            if (nextline !~ /^#/) {
+               line = line " " nextline
+               # Go back to stripping @" "@ pairs
+               break
+            }
+         } else {
+            print "line", lineno ": unterminated PNG_DFN string"
+            err=1
+            next
+         }
+      }
+   }
+
+   # Put any needed double quotes in (at the end, because these would otherwise
+   # interfere with the processing above.)
+   gsub(/@'/,"\"", line)
+
+   # Remove any trailing spaces (not really required, but for
+   # editorial consistency
+   sub(/ *$/, "", line)
+
+   # Remove trailing CR
+   sub(/
+$/, "", line)
+
+   if (sort) {
+      if (split(line, parts) < sort) {
+         print "line", lineno ": missing sort field:", line
+         err=1
+      } else
+         array[parts[sort]] = line
+   }
+
+   else
+      print line >out
+   next
+}
+
+/PNG_DFN/{
+   print "line", NR, "incorrectly formated PNG_DFN line:"
+   print $0
+   err = 1
+}
+
+END{
+   if (out_count > 0 || err > 0)
+	exit err
+
+   print "no definition lines found"
+   exit 1

scripts/intprefix.dfn

@@ -10,10 +10,10 @@
  */
 
 #define PNG_INTERNAL_DATA(type, name, array)\
-	PNG_DEFN_MAGIC-name-PNG_DEFN_END
+        PNG_DFN "@" name "@"
 
 #define PNG_INTERNAL_FUNCTION(type, name, args, attributes)\
-	PNG_DEFN_MAGIC-name-PNG_DEFN_END
+        PNG_DFN "@" name "@"
 
 #define PNGPREFIX_H /* self generation */
 #include "../pngpriv.h"

scripts/libpng-config-head.in

@@ -11,7 +11,7 @@
 
 # Modeled after libxml-config.
 
-version=1.7.0alpha09
+version=1.6.3beta06
 prefix=""
 libdir=""
 libs=""

scripts/libpng.pc.in

@@ -1,10 +1,10 @@
 prefix=@prefix@
 exec_prefix=@exec_prefix@
 libdir=@libdir@
-includedir=@includedir@/libpng17
+includedir=@includedir@/libpng16
 
 Name: libpng
 Description: Loads and saves PNG files
-Version: 1.7.0alpha09
-Libs: -L${libdir} -lpng17
+Version: 1.6.3beta06
+Libs: -L${libdir} -lpng16
 Cflags: -I${includedir}

scripts/makefile.32sunu

@@ -9,8 +9,8 @@
 # and license in png.h
 
 # Library name:
-LIBNAME=libpng17
-PNGMAJ = 17
+LIBNAME=libpng16
+PNGMAJ = 16
 
 # Shared library names:
 LIBSO=$(LIBNAME).so
@@ -29,7 +29,7 @@ RM_F=/bin/rm -f
 SUN_CC_FLAGS=-fast -xtarget=ultra
 SUN_LD_FLAGS=-fast -xtarget=ultra
 
-# where make install puts libpng.a, libpng17.so and libpng17/png.h
+# where make install puts libpng.a, libpng16.so and libpng16/png.h
 prefix=/a
 exec_prefix=$(prefix)
 
@@ -95,7 +95,7 @@ libpng.pc:
 	-e s!@exec_prefix@!$(exec_prefix)! \
 	-e s!@libdir@!$(LIBPATH)! \
 	-e s!@includedir@!$(INCPATH)! \
-	-e s!-lpng17!-lpng17\ -lz\ -lm! > libpng.pc
+	-e s!-lpng16!-lpng16\ -lz\ -lm! > libpng.pc
 
 libpng-config:
 	( cat scripts/libpng-config-head.in; \
@@ -106,7 +106,7 @@ libpng-config:
 	echo R_opts=\"-R$(LIBPATH)\"; \
 	echo ccopts=\"-xtarget=ultra\"; \
 	echo ldopts=\"-xtarget=ultra\"; \
-	echo libs=\"-lpng17 -lz -lm\"; \
+	echo libs=\"-lpng16 -lz -lm\"; \
 	cat scripts/libpng-config-body.in ) > libpng-config
 	chmod +x libpng-config
 

scripts/makefile.64sunu

@@ -9,8 +9,8 @@
 # and license in png.h
 
 # Library name:
-LIBNAME=libpng17
-PNGMAJ = 17
+LIBNAME=libpng16
+PNGMAJ = 16
 
 # Shared library names:
 LIBSO=$(LIBNAME).so
@@ -29,7 +29,7 @@ RM_F=/bin/rm -f
 SUN_CC_FLAGS=-fast -xtarget=ultra -xarch=v9
 SUN_LD_FLAGS=-fast -xtarget=ultra -xarch=v9
 
-# where make install puts libpng.a, libpng17.so and libpng17/png.h
+# where make install puts libpng.a, libpng16.so and libpng16/png.h
 prefix=/a
 exec_prefix=$(prefix)
 
@@ -47,7 +47,7 @@ WARNMORE=-Wwrite-strings -Wpointer-arith -Wshadow \
 	-Wstrict-prototypes -Wmissing-prototypes #-Wconversion
 CFLAGS=-I$(ZLIBINC) $(SUN_CC_FLAGS) \
 	# $(WARNMORE) -g -DPNG_DEBUG=5
-LDFLAGS=-L. -R. $(SUN_LD_FLAGS) -L$(ZLIBLIB) -R$(ZLIBLIB) -lpng17 -lz -lm
+LDFLAGS=-L. -R. $(SUN_LD_FLAGS) -L$(ZLIBLIB) -R$(ZLIBLIB) -lpng16 -lz -lm
 
 INCPATH=$(prefix)/include
 LIBPATH=$(exec_prefix)/lib
@@ -95,7 +95,7 @@ libpng.pc:
 	-e s!@exec_prefix@!$(exec_prefix)! \
 	-e s!@libdir@!$(LIBPATH)! \
 	-e s!@includedir@!$(INCPATH)! \
-	-e s!-lpng17!-lpng17\ -lz\ -lm! > libpng.pc
+	-e s!-lpng16!-lpng16\ -lz\ -lm! > libpng.pc
 
 libpng-config:
 	( cat scripts/libpng-config-head.in; \
@@ -106,7 +106,7 @@ libpng-config:
 	echo R_opts=\"-R$(LIBPATH)\"; \
 	echo ccopts=\"-xtarget=ultra -xarch=v9\"; \
 	echo ldopts=\"-xtarget=ultra -xarch=v9\"; \
-	echo libs=\"-lpng17 -lz -lm\"; \
+	echo libs=\"-lpng16 -lz -lm\"; \
 	cat scripts/libpng-config-body.in ) > libpng-config
 	chmod +x libpng-config
 

scripts/makefile.aix

@@ -21,8 +21,8 @@ RANLIB = ranlib
 RM_F = rm -f
 LN_SF = ln -f -s
 
-LIBNAME=libpng17
-PNGMAJ = 17
+LIBNAME=libpng16
+PNGMAJ = 16
 
 prefix=/usr/local
 INCPATH=$(prefix)/include
@@ -47,7 +47,7 @@ CRELEASE = -O2
 LDRELEASE = -s
 WARNMORE=-W -Wall
 CFLAGS = -I$(ZLIBINC) $(WARNMORE) $(CRELEASE)
-LDFLAGS = -L. -L$(ZLIBLIB) -lpng17 -lz -lm $(LDRELEASE)
+LDFLAGS = -L. -L$(ZLIBLIB) -lpng16 -lz -lm $(LDRELEASE)
 
 # File extensions
 O=.o

scripts/makefile.beos

@@ -9,8 +9,8 @@
 # and license in png.h
 
 # Library name:
-LIBNAME=libpng17
-PNGMAJ = 17
+LIBNAME=libpng16
+PNGMAJ = 16
 
 # Shared library names:
 LIBSO=$(LIBNAME).so
@@ -45,7 +45,7 @@ CFLAGS=-I$(ZLIBINC) -W -Wall -O1 -funroll-loops \
 # LDFLAGS=-L. -Wl,-rpath,. -L$(ZLIBLIB) -Wl,-rpath,$(ZLIBLIB) -lpng -lz
 LDFLAGS=-L. -Wl,-soname=$(LIBSOMAJ) -L$(ZLIBLIB) -lz
 
-# where make install puts libpng.a, libpng17.so*, and png.h
+# where make install puts libpng.a, libpng16.so*, and png.h
 prefix=/usr/local
 exec_prefix=$(prefix)
 INCPATH=$(prefix)/include
@@ -91,13 +91,13 @@ libpng.pc:
 	-e s!@exec_prefix@!$(exec_prefix)! \
 	-e s!@libdir@!$(LIBPATH)! \
 	-e s!@includedir@!$(INCPATH)! \
-	-e s!-lpng17!-lpng17\ -lz\ -lm! > libpng.pc
+	-e s!-lpng16!-lpng16\ -lz\ -lm! > libpng.pc
 
 libpng-config:
 	( cat scripts/libpng-config-head.in; \
 	echo prefix=\"$(prefix)\"; \
 	echo I_opts=\"-I$(INCPATH)/$(LIBNAME)\"; \
-	echo libs=\"-lpng17 -lz \"; \
+	echo libs=\"-lpng16 -lz \"; \
 	cat scripts/libpng-config-body.in ) > libpng-config
 	chmod +x libpng-config
 
@@ -110,7 +110,7 @@ $(LIBSOMAJ): $(OBJSDLL)
 	$(LIBSOMAJ) $(OBJSDLL) $(LDFLAGS)
 
 pngtest: pngtest.o $(LIBSO)
-	$(CC) -L$(ZLIBLIB) -L. -lz -lpng17 -o pngtest pngtest.o
+	$(CC) -L$(ZLIBLIB) -L. -lz -lpng16 -o pngtest pngtest.o
 
 test: pngtest
 	./pngtest

scripts/makefile.cegcc

@@ -22,16 +22,16 @@
 # make clean
 
 VERMAJ = 1
-VERMIN = 7
-VERMIC = 0
+VERMIN = 6
+VERMIC = 3
 VER = $(VERMAJ).$(VERMIN).$(VERMIC)
 NAME = libpng
 PACKAGE = $(NAME)-$(VER)
 
-BIN = libpng17-0.dll
-LIB = libpng17.a libpng17.dll.a libpng.a libpng.dll.a
+BIN = libpng16-0.dll
+LIB = libpng16.a libpng16.dll.a libpng.a libpng.dll.a
 INCLUDE = png.h pngconf.h pnglibconf.h pngpriv.h pngstruct.h             pnginfo.h pngdebug.h
-PC = libpng17.pc libpng.pc
+PC = libpng16.pc libpng.pc
 
 MANIFESTVERBIN = "Libpng-$(VER): Binary files"
 MANIFESTVERDEV = "Libpng-$(VER): Developer files"

scripts/makefile.darwin

@@ -9,7 +9,7 @@
 # For conditions of distribution and use, see the disclaimer
 # and license in png.h
 
-# where "make install" puts libpng.a, libpng17.dylib, png.h, pngconf.h,
+# where "make install" puts libpng.a, libpng16.dylib, png.h, pngconf.h,
 # and pnglibconf.h
 prefix=/usr/local
 exec_prefix=$(prefix)
@@ -19,8 +19,8 @@ ZLIBLIB=/usr/lib
 ZLIBINC=/usr/include
 
 # Library name:
-LIBNAME = libpng17
-PNGMAJ = 17
+LIBNAME = libpng16
+PNGMAJ = 16
 
 # Shared library names:
 LIBSO=$(LIBNAME).dylib
@@ -39,7 +39,7 @@ ARCH=-arch ppc -arch i386 -arch x86_64
 
 # CFLAGS=-I$(ZLIBINC) -W -Wall -O3 -funroll-loops
 CFLAGS=-I$(ZLIBINC) -W -Wall -O -funroll-loops $(ARCH)
-LDFLAGS=-L. -L$(ZLIBLIB) -lpng17 -lz $(ARCH)
+LDFLAGS=-L. -L$(ZLIBLIB) -lpng16 -lz $(ARCH)
 
 INCPATH=$(prefix)/include
 LIBPATH=$(exec_prefix)/lib
@@ -87,14 +87,14 @@ libpng.pc:
 	-e s!@exec_prefix@!$(exec_prefix)! \
 	-e s!@libdir@!$(LIBPATH)! \
 	-e s!@includedir@!$(INCPATH)! \
-	-e s!-lpng17!-lpng17\ -lz! > libpng.pc
+	-e s!-lpng16!-lpng16\ -lz! > libpng.pc
 
 libpng-config:
 	( cat scripts/libpng-config-head.in; \
 	echo prefix=\"$(prefix)\"; \
 	echo I_opts=\"-I$(INCPATH)/$(LIBNAME)\"; \
 	echo L_opts=\"-L$(LIBPATH)\"; \
-	echo libs=\"-lpng17 -lz\"; \
+	echo libs=\"-lpng16 -lz\"; \
 	cat scripts/libpng-config-body.in ) > libpng-config
 	chmod +x libpng-config
 
@@ -104,7 +104,7 @@ $(LIBSO): $(LIBSOMAJ)
 $(LIBSOMAJ): $(OBJSDLL)
 	$(CC) -dynamiclib \
 	 -install_name $(LIBPATH)/$(LIBSOMAJ) \
-	 -current_version 17 -compatibility_version 17 \
+	 -current_version 16 -compatibility_version 16 \
 	 $(ARCH) -o $(LIBSOMAJ) \
 	 $(OBJSDLL) -L$(ZLIBLIB) -lz
 

scripts/makefile.dec

@@ -7,8 +7,8 @@
 # and license in png.h
 
 # Library name:
-PNGMAJ = 17
-LIBNAME = libpng17
+PNGMAJ = 16
+LIBNAME = libpng16
 
 # Shared library names:
 LIBSO=$(LIBNAME).so
@@ -75,7 +75,7 @@ libpng.pc:
 	-e s!@exec_prefix@!$(exec_prefix)! \
 	-e s!@libdir@!$(LIBPATH)! \
 	-e s!@includedir@!$(INCPATH)! \
-	-e s!-lpng17!-lpng17\ -lz\ -lm! > libpng.pc
+	-e s!-lpng16!-lpng16\ -lz\ -lm! > libpng.pc
 
 libpng-config:
 	( cat scripts/libpng-config-head.in; \
@@ -83,7 +83,7 @@ libpng-config:
 	echo I_opts=\"-I$(INCPATH)/$(LIBNAME)\"; \
 	echo ccopts=\"-std\"; \
 	echo L_opts=\"-L$(LIBPATH)\"; \
-	echo libs=\"-lpng17 -lz -lm\"; \
+	echo libs=\"-lpng16 -lz -lm\"; \
 	cat scripts/libpng-config-body.in ) > libpng-config
 	chmod +x libpng-config
 

scripts/makefile.elf

@@ -1,4 +1,4 @@
-# makefile for libpng.a and libpng17.so on Linux ELF with gcc
+# makefile for libpng.a and libpng16.so on Linux ELF with gcc
 # Copyright (C) 1998, 1999, 2002, 2006, 2008, 2010-2011 Greg Roelofs
 # and Glenn Randers-Pehrson
 # Copyright (C) 1996, 1997 Andreas Dilger
@@ -10,19 +10,19 @@
 # Modified for Debian by Junichi Uekawa and Josselin Mouette
 # Major modifications are:
 #    * link libpng explicitly with libz and libm
-#    * $(OLDSO).17 is a symlink rather than a different library
+#    * $(OLDSO).16 is a symlink rather than a different library
 #    * versioned symbols
 
 # Library name:
-LIBNAME = libpng17
-PNGMAJ = 17
+LIBNAME = libpng16
+PNGMAJ = 16
 
 # Shared library names:
 LIBSO=$(LIBNAME).so
 LIBSOMAJ=$(LIBNAME).so.$(PNGMAJ)
 LIBSOREL=$(LIBSOMAJ).$(RELEASE)
 OLDSO=libpng.so
-OLDSOMAJ=libpng.so.17
+OLDSOMAJ=libpng.so.16
 
 # Utilities:
 AR_RC=ar rc
@@ -32,8 +32,8 @@ LN_SF=ln -sf
 RANLIB=ranlib
 RM_F=/bin/rm -f
 
-# where "make install" puts libpng17.a, libpng17.so*,
-# libpng17/png.h, libpng17/pngconf.h, and libpng17/pnglibconf.h
+# where "make install" puts libpng16.a, libpng16.so*,
+# libpng16/png.h, libpng16/pngconf.h, and libpng16/pnglibconf.h
 # Prefix must be a full pathname.
 prefix=/usr/local
 exec_prefix=$(prefix)
@@ -57,7 +57,7 @@ WARNMORE=-Wwrite-strings -Wpointer-arith -Wshadow \
 CFLAGS=-W -Wall -D_REENTRANT -O2 \
 	$(ALIGN) # $(WARNMORE) -g -DPNG_DEBUG=5
 
-LDFLAGS=-L. -lpng17
+LDFLAGS=-L. -lpng16
 LDFLAGS_A=libpng.a -lz -lm
 LIBADDFLAGS=-lz -lm
 
@@ -108,11 +108,11 @@ libpng.pc:
 	-e s!@exec_prefix@!$(exec_prefix)! \
 	-e s!@libdir@!$(LIBPATH)! \
 	-e s!@includedir@!$(INCPATH)! \
-	-e s!-lpng17!-lpng17\ -lz\ -lm! > libpng.pc
+	-e s!-lpng16!-lpng16\ -lz\ -lm! > libpng.pc
 
 libpng.syms: png.h pngconf.h pnglibconf.h
 	$(CC) $(CFLAGS) -E -DPNG_BUILDSYMS -DPNG_INTERNAL png.h |\
-	awk -F '[\t [\\]();]' -v PNGMAJ=$(PNGMAJ) 'BEGIN{printf("PNG17_%s {global:\n",PNGMAJ)}\
+	awk -F '[\t [\\]();]' -v PNGMAJ=$(PNGMAJ) 'BEGIN{printf("PNG16_%s {global:\n",PNGMAJ)}\
 	{ for (i=1;i+2<=NF;++i)\
 		if ($$(i)=="PNG_FUNCTION_EXPORT" && $$(i+2)=="END")\
 			print $$(i+1) ";";\
@@ -129,8 +129,8 @@ libpng-config:
 	echo I_opts=\"-I$(INCPATH)/$(LIBNAME)\"; \
 	echo L_opts=\"\"; \
 	echo R_opts=\"\"; \
-	echo libs=\"-lpng17\"; \
-	echo all_libs=\"-lpng17 $(LIBADDFLAGS)\"; \
+	echo libs=\"-lpng16\"; \
+	echo all_libs=\"-lpng16 $(LIBADDFLAGS)\"; \
 	cat scripts/libpng-config-body.in ) > libpng-config
 	chmod +x libpng-config
 

scripts/makefile.freebsd

@@ -6,7 +6,7 @@
 # and license in png.h
 
 PREFIX?=        /usr/local
-SHLIB_VER?=     17
+SHLIB_VER?=     16
 
 LIB=		png
 SHLIB_MAJOR=	${SHLIB_VER}
@@ -26,19 +26,24 @@ SYMLINKS=       libpng/png.h ${INCSDIR}/../png.h \
 		libpng/pngconf.h ${INCSDIR}/../pngconf.h \
 		libpng/pnglibconf.h ${INCSDIR}/../pnglibconf.h
 
-LDADD+=         -lm -lz
-#LDADD+=         -lm -lz -lssp_nonshared   # for OSVERSION < 800000 ?
+# where make install finds libz.a and zlib.h
+ZLIBLIB=	/usr/lib
+ZLIBINC=	/usr/include
+
+LDADD+=        -lm -lz
+#LDADD+=       -lm -lz -lssp_nonshared   # for OSVERSION < 800000 ?
 
 DPADD+=         ${LIBM} ${LIBZ}
 
-CFLAGS+= -I.
+CFLAGS+= -I. -I${ZLIBINC}
 
 SRCS=	png.c pngset.c pngget.c pngrutil.c pngtrans.c pngwutil.c \
 	pngread.c pngrio.c pngwio.c pngwrite.c pngrtran.c \
 	pngwtran.c pngmem.c pngerror.c pngpread.c
 
 pngtest: pngtest.o libpng.a
-	${CC} ${CFLAGS} -L. -static -o pngtest pngtest.o -lpng -lz -lm
+	${CC} ${CFLAGS} -L. -static -o pngtest pngtest.o -L${ZLIBLIB} \
+	-lpng ${LDADD}
 
 CLEANFILES= pngtest pngtest.o pngout.png
 

scripts/makefile.hp64

@@ -19,8 +19,8 @@ ZLIBINC=/opt/zlib/include
 #   SHAREDLIB=libz.sl
 
 # Library name:
-LIBNAME = libpng17
-PNGMAJ = 17
+LIBNAME = libpng16
+PNGMAJ = 16
 
 # Shared library names:
 LIBSO=$(LIBNAME).sl
@@ -44,7 +44,7 @@ CCFLAGS=-I$(ZLIBINC) -O -Ae -Wl,+vnocompatwarnings +DD64 \
 
 LDFLAGS=-L. -L$(ZLIBLIB) -lpng -lz -lm
 
-# where make install puts libpng.a, libpng17.sl, and png.h
+# where make install puts libpng.a, libpng16.sl, and png.h
 prefix=/opt/libpng
 exec_prefix=$(prefix)
 INCPATH=$(prefix)/include
@@ -93,7 +93,7 @@ libpng.pc:
 	-e s!@exec_prefix@!$(exec_prefix)! \
 	-e s!@libdir@!$(LIBPATH)! \
 	-e s!@includedir@!$(INCPATH)! \
-	-e s!-lpng17!-lpng17\ -lz\ -lm! > libpng.pc
+	-e s!-lpng16!-lpng16\ -lz\ -lm! > libpng.pc
 
 libpng-config:
 	( cat scripts/libpng-config-head.in; \
@@ -101,7 +101,7 @@ libpng-config:
 	echo I_opts=\"-I$(INCPATH)/$(LIBNAME)\"; \
 	echo ccopts=\"-Ae +DA1.1 +DS2.0\"; \
 	echo L_opts=\"-L$(LIBPATH)\"; \
-	echo libs=\"-lpng17 -lz -lm\"; \
+	echo libs=\"-lpng16 -lz -lm\"; \
 	cat scripts/libpng-config-body.in ) > libpng-config
 	chmod +x libpng-config
 

scripts/makefile.hpgcc

@@ -9,8 +9,8 @@
 # and license in png.h
 
 # Library name:
-LIBNAME = libpng17
-PNGMAJ = 17
+LIBNAME = libpng16
+PNGMAJ = 16
 
 # Shared library names:
 LIBSO=$(LIBNAME).sl
@@ -55,8 +55,8 @@ WARNMORE=-Wwrite-strings -Wpointer-arith -Wshadow \
 
 CFLAGS=-I$(ZLIBINC) -W -Wall -O3 -funroll-loops -DPNG_NO_MMX_CODE \
 	$(ALIGN) # $(WARNMORE) -g -DPNG_DEBUG=5
-#LDFLAGS=-L. -Wl,-rpath,. -L$(ZLIBLIB) -Wl,-rpath,$(ZLIBLIB) -lpng17 -lz -lm
-LDFLAGS=-L. -L$(ZLIBLIB) -lpng17 -lz -lm
+#LDFLAGS=-L. -Wl,-rpath,. -L$(ZLIBLIB) -Wl,-rpath,$(ZLIBLIB) -lpng16 -lz -lm
+LDFLAGS=-L. -L$(ZLIBLIB) -lpng16 -lz -lm
 
 INCPATH=$(prefix)/include
 LIBPATH=$(exec_prefix)/lib
@@ -100,13 +100,13 @@ libpng.pc:
 	-e s!@exec_prefix@!$(exec_prefix)! \
 	-e s!@libdir@!$(LIBPATH)! \
 	-e s!@includedir@!$(INCPATH)! \
-	-e s!-lpng17!-lpng17\ -lz\ -lm! > libpng.pc
+	-e s!-lpng16!-lpng16\ -lz\ -lm! > libpng.pc
 
 libpng-config:
 	( cat scripts/libpng-config-head.in; \
 	echo prefix=\"$(prefix)\"; \
 	echo I_opts=\"-I$(INCPATH)/$(LIBNAME)\"; \
-	echo libs=\"-lpng17 -lz -lm\"; \
+	echo libs=\"-lpng16 -lz -lm\"; \
 	cat scripts/libpng-config-body.in ) > libpng-config
 	chmod +x libpng-config
 

scripts/makefile.hpux

@@ -19,8 +19,8 @@ ZLIBINC=/opt/zlib/include
 #   SHAREDLIB=libz.sl
 
 # Library name:
-LIBNAME = libpng17
-PNGMAJ = 17
+LIBNAME = libpng16
+PNGMAJ = 16
 
 # Shared library names:
 LIBSO=$(LIBNAME).sl
@@ -36,7 +36,7 @@ LN_SF=ln -sf
 RANLIB=ranlib
 RM_F=/bin/rm -f
 
-# where make install puts libpng.a, libpng17.sl, and png.h
+# where make install puts libpng.a, libpng16.sl, and png.h
 prefix=/opt/libpng
 exec_prefix=$(prefix)
 INCPATH=$(prefix)/include
@@ -90,7 +90,7 @@ libpng.pc:
 	-e s!@exec_prefix@!$(exec_prefix)! \
 	-e s!@libdir@!$(LIBPATH)! \
 	-e s!@includedir@!$(INCPATH)! \
-	-e s!-lpng17!-lpng17\ -lz\ -lm! > libpng.pc
+	-e s!-lpng16!-lpng16\ -lz\ -lm! > libpng.pc
 
 libpng-config:
 	( cat scripts/libpng-config-head.in; \
@@ -98,7 +98,7 @@ libpng-config:
 	echo I_opts=\"-I$(INCPATH)/$(LIBNAME)\"; \
 	echo ccopts=\"-Ae +DA1.1 +DS2.0\"; \
 	echo L_opts=\"-L$(LIBPATH)\"; \
-	echo libs=\"-lpng17 -lz -lm\"; \
+	echo libs=\"-lpng16 -lz -lm\"; \
 	cat scripts/libpng-config-body.in ) > libpng-config
 	chmod +x libpng-config