[master] Imported from libpng-1.6.18.tar

[master] Imported from libpng-1.6.17.tar
[master] Imported from libpng-1.6.16.tar
2025-07-10 18:04:09 +02:00 · 2015-07-22 22:41:05 -05:00 · 2015-03-26 08:11:22 -05:00 · 2015-01-15 12:47:40 -05:00 · 2014-11-20 10:23:30 -06:00 · 2014-10-22 19:33:27 -05:00
243 changed files with 2542 additions and 6553 deletions
--- a/85
+++ b/85
@@ -1,38 +1,85 @@
-Libpng 1.6.23beta01 - May 29, 2016
+Libpng 1.6.18 - July 23, 2015

-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.
+This is a public release of libpng, intended for use in production codes.

 Files available for download:

 Source files with LF line endings (for Unix/Linux) and with a
 "configure" script

-   1.6.23beta01.tar.xz (LZMA-compressed, recommended)
-   1.6.23beta01.tar.gz
+   libpng-1.6.18.tar.xz (LZMA-compressed, recommended)
+   libpng-1.6.18.tar.gz

 Source files with CRLF line endings (for Windows), without the
 "configure" script

-   lp1623b01.7z  (LZMA-compressed, recommended)
-   lp1623b01.zip
+   lpng1618.7z  (LZMA-compressed, recommended)
+   lpng1618.zip

 Other information:

-   1.6.23beta01-README.txt
-   1.6.23beta01-LICENSE.txt
-   libpng-1.6.23beta01-*.asc (armored detached GPG signatures)
+   libpng-1.6.18-README.txt
+   libpng-1.6.18-LICENSE.txt
+   libpng-1.6.18-*.asc (armored detached GPG signatures)

-Changes since the last public release (1.6.22):
-
-Version 1.6.23beta01 [May 29, 2016]
-  Stop a potential memory leak in png_set_tRNS() (Bug report by Ted Ying).
-  Fixed the progressive reader to handle empty first IDAT chunk properly
-    (patch by Timothy Nikkel).  This bug was introduced in libpng-1.6.0 and
-    only affected the libpng16 branch.
-  Added tests in pngvalid.c to check zero-length IDAT chunks in various
-    positions.  Fixed the sequential reader to handle these more robustly
+Changes since the last public release (1.6.17):
+  Removed PNG_SET_CHUNK_[CACHE|MALLOC]_LIMIT_SUPPORTED macros.  They
+    have been combined with PNG_SET_USER_LIMITS_SUPPORTED (resolves
+    bug report by Andrew Church).
+  Fixed rgb_to_gray checks and added tRNS checks to pngvalid.c.  This
+    fixes some arithmetic errors that caused some tests to fail on
+    some 32-bit platforms (Bug reports by Peter Breitenlohner [i686]
+    and Petr Gajdos [i586]).
+  Suppressed some warnings from the Borland C++ 5.5.1/5.82 compiler
+    (Bug report by Viktor Szaka'ts).
+  Replaced "unexpected" with an integer (0xabadca11) in pngset.c
+    where a long was expected, to avoid a compiler warning when PNG_DEBUG > 1.
+  Added contrib/examples/simpleover.c, to demonstrate how to handle
+    alpha compositing of multiple images, using the "simplified API"
+    and an example PNG generation tool, contrib/examples/genpng.c
    (John Bowler).
+  PNG_RELEASE_BUILD replaces tests where the code depended on the build base
+    type and can be defined on the command line, allowing testing in beta
+    builds (John Bowler).
+  Avoid Coverity issue 80858 (REVERSE NULL) in pngtest.c
+  Avoid a harmless potential integer overflow in png_XYZ_from_xy() (Bug
+    report from Christopher Ferris).
+  Backport filter selection code from libpng-1.7.0beta51, to combine
+    sub_row, up_row, avg_row, and paeth_row into try_row and tst_row.
+  Changed png_voidcast(), etc., to voidcast(), etc., in contrib/tools/pngfix.c
+    to avoid confusion with the libpng private macros.
+  Fixed old cut&paste bug in the weighted filter selection code in
+    pngwutil.c, introduced in libpng-0.95, March 1997.
+  Removed WRITE_WEIGHTED_FILTERED code, to save a few kbytes of the
+    compiled library size. It never worked properly and as far as we can
+    tell, no one uses it. The png_set_filter_heuristics() and
+    png_set_filter_heuristics_fixed() APIs are retained but deprecated
+    and do nothing.
+  Quieted some Coverity issues in pngfix.c, png-fix-itxt.c, pngvalid.c,
+    pngstest.c, and pngimage.c. Most seem harmless, but png-fix-itxt
+    would only work with iTXt chunks with length 255 or less.
+  Removed non-working progressive reader 'skip' function. This
+    function has apparently never been used. It was implemented
+    to support back-door modification of png_struct in libpng-1.4.x
+    but (because it does nothing and cannot do anything) was apparently
+    never tested (John Bowler).
+  Fixed cexcept.h in which GCC 5 now reports that one of the auto
+    variables in the Try macro needs to be volatile to prevent value
+    being lost over the setjmp (John Bowler).
+  Added #ifdef's to contrib/examples programs so people don't try
+    to compile them without the minimum required support enabled
+    (suggested by Flavio Medeiros).
+  Eliminated the final two Coverity defects (insecure temporary file
+    handling in contrib/libtests/pngstest.c; possible overflow of
+    unsigned char in contrib/tools/png-fix-itxt.c). To use the "secure"
+    file handling, define PNG_USE_MKSTEMP, otherwise "tmpfile()" will
+    be used.
+  Removed some unused WEIGHTED_FILTER macros from pngstruct.h
+  Replaced arbitrary use of 'extern' with #define PNG_LINKAGE_*.  To
+    preserve API compatibility, the new defines all default to "extern"
+    (requested by Jan Nijtmans).
+  Belatedly added Mans Rullgard and James Yu to the list of Contributing
+    Authors.

 Send comments/corrections/commendations to png-mng-implement at lists.sf.net
 (subscription required; visit
--- a/309
+++ b/309
@@ -3756,9 +3756,8 @@ Version 1.5.7beta04 [November 17, 2011]

 Version 1.5.7beta05 [November 25, 2011]
  Removed "zTXt" from warning in generic chunk decompression function.
-  Validate time settings passed to png_set_tIME() and png_convert_to_rfc1123()
-    (Frank Busse). Note: This prevented CVE-2015-7981 from affecting
-    libpng-1.5.7 and later.
+  Validate time settings passed to pngset() and png_convert_to_rfc1123()
+    (Frank Busse).
  Added MINGW support to CMakeLists.txt
  Reject invalid compression flag or method when reading the iTXt chunk.
  Backed out 'simplified' API changes. The API seems too complex and there
@@ -3804,13 +3803,12 @@ Version 1.6.0beta01 [December 15, 2011]
    (the other two required headers aren't used).  Non-ANSI systems that don't
    have stddef.h or limits.h will have to provide an appropriate fake
    containing the relevant types and #defines.
-  Dropped support for 16-bit platforms. The use of FAR/far has been eliminated
-    and the definition of png_alloc_size_t is now controlled by a flag so
-    that 'small size_t' systems can select it if necessary.  Libpng 1.6 may
-    not currently work on such systems -- it seems likely that it will
-    ask 'malloc' for more than 65535 bytes with any image that has a
-    sufficiently large row size (rather than simply failing to read such
-    images).
+  The use of FAR/far has been eliminated and the definition of png_alloc_size_t
+    is now controlled by a flag so that 'small size_t' systems can select it
+    if necessary.  Libpng 1.6 may not currently work on such systems -- it
+    seems likely that it will ask 'malloc' for more than 65535 bytes with any
+    image that has a sufficiently large row size (rather than simply failing
+    to read such images).
  New tools directory containing tools used to generate libpng code.
  Fixed race conditions in parallel make builds. With higher degrees of
    parallelism during 'make' the use of the same temporary file names such
@@ -4422,7 +4420,7 @@ Version 1.6.1beta02 [February 19, 2013]

 Version 1.6.1beta03 [February 22, 2013]
  Fixed ALIGNED_MEMORY support.
-  Added a new configure option:
+  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
@@ -4441,10 +4439,10 @@ Version 1.6.1beta05 [March 1, 2013]
 Version 1.6.1beta06 [March 4, 2013]
  Better documentation of unknown handling API interactions.
  Corrected Android builds and corrected libpng.vers with symbol
-    prefixing.  It also makes those tests compile and link on Android.
-  Added an API png_set_option() to set optimization options externally,
+    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, using the PNG_ARM_NEON option.
+    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.
@@ -4542,8 +4540,7 @@ 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, via a new PNG_MAXIMUM_INFLATE_WINDOW
-    option for png_set_options().
+    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.
@@ -5063,8 +5060,7 @@ Version 1.6.15beta04 [November 4, 2014]
 Version 1.6.15beta05 [November 5, 2014]
  Use png_get_libpng_ver(NULL) instead of PNG_LIBPNG_VER_STRING in
    example.c, pngtest.c, and applications in the contrib directory.
-  Fixed an out-of-range read in png_user_version_check() (Bug report from
-    Qixue Xiao, CVE-2015-8540).
+  Avoid out-of-bounds memory access in png_user_version_check().
  Simplified and future-proofed png_user_version_check().
  Fixed GCC unsigned int->float warnings. Various versions of GCC
    seem to generate warnings when an unsigned value is implicitly
@@ -5147,9 +5143,7 @@ Version 1.6.17beta01 [January 29, 2015]
  Added testing of png_set_packing() to pngvalid.c
  Regenerated configure scripts in the *.tar distributions with libtool-2.4.4
  Implement previously untested cases of libpng transforms in pngvalid.c
-  Fixed byte order in png_do_read_filler() with 16-bit input. Previously
-    the high and low bytes of the filler, from png_set_filler() or from
-    png_set_add_alpha(), were read in the wrong order.
+  Fixed byte order in 2-byte filler, in png_do_read_filler().
  Made the check for out-of-range values in png_set_tRNS() detect
    values that are exactly 2^bit_depth, and work on 16-bit platforms.
  Merged some parts of libpng-1.6.17beta01 and libpng-1.7.0beta47.
@@ -5231,7 +5225,7 @@ Version 1.6.18beta01 [April 1, 2015]

 Version 1.6.18beta02 [April 26, 2015]
  Suppressed some warnings from the Borland C++ 5.5.1/5.82 compiler
-    (Bug report by Viktor Szakats).
+    (Bug report by Viktor Szaka'ts).

 Version 1.6.18beta03 [May 6, 2015]
  Replaced "unexpected" with an integer (0xabadca11) in pngset.c
@@ -5311,277 +5305,6 @@ Version 1.6.18rc03 [July 15, 2015]
 Version 1.6.18 [July 23, 2015]
  No changes.

-Version 1.6.19beta01 [July 30, 2015]
-  Updated obsolete information about the simplified API macros in the
-    manual pages (Bug report by Arc Riley).
-  Avoid potentially dereferencing NULL info_ptr in png_info_init_3().
-  Rearranged png.h to put the major sections in the same order as
-    in libpng17.
-  Eliminated unused PNG_COST_SHIFT, PNG_WEIGHT_SHIFT, PNG_COST_FACTOR, and
-    PNG_WEIGHT_FACTOR macros.
-  Suppressed some warnings from the Borland C++ 5.5.1/5.82 compiler
-    (Bug report by Viktor Szakats).  Several warnings remain and are
-    unavoidable, where we test for overflow.
-  Fixed potential leak of png_pixels in contrib/pngminus/pnm2png.c
-  Fixed uninitialized variable in contrib/gregbook/rpng2-x.c
-
-Version 1.6.19beta02 [August 19, 2015]
-  Moved config.h.in~ from the "libpng_autotools_files" list to the
-    "libpng_autotools_extra" list in autogen.sh because it was causing a
-    false positive for missing files (bug report by Robert C. Seacord).
-  Removed unreachable "break" statements in png.c, pngread.c, and pngrtran.c
-    to suppress clang warnings (Bug report by Viktor Szakats).
-  Fixed some bad links in the man page.
-  Changed "n bit" to "n-bit" in comments.
-  Added signed/unsigned 16-bit safety net. This removes the dubious
-    0x8000 flag definitions on 16-bit systems. They aren't supported
-    yet the defs *probably* work, however it seems much safer to do this
-    and be advised if anyone, contrary to advice, is building libpng 1.6
-    on a 16-bit system. It also adds back various switch default clauses
-    for GCC; GCC errors out if they are not present (with an appropriately
-    high level of warnings).
-  Safely convert num_bytes to a png_byte in png_set_sig_bytes() (Robert
-    Seacord).
-  Fixed the recently reported 1's complement security issue by replacing
-    the value that is illegal in the PNG spec, in both signed and unsigned
-    values, with 0. Illegal unsigned values (anything greater than or equal
-    to  0x80000000) can still pass through, but since these are not illegal
-    in ANSI-C (unlike 0x80000000 in the signed case) the checking that
-    occurs later can catch them (John Bowler).
-
-Version 1.6.19beta03 [September 26, 2015]
-  Fixed png_save_int_32 when int is not 2's complement (John Bowler).
-  Updated libpng16 with all the recent test changes from libpng17,
-    including changes to pngvalid.c to ensure that the original,
-    distributed, version of contrib/visupng/cexcept.h can be used
-    (John Bowler).
-  pngvalid contains the correction to the use of SAVE/STORE_
-    UNKNOWN_CHUNKS; a bug revealed by changes in libpng 1.7. More
-    tests contain the --strict option to detect warnings and the
-    pngvalid-standard test has been corrected so that it does not
-    turn on progressive-read. There is a separate test which does
-    that. (John Bowler)
-  Also made some signed/unsigned fixes.
-  Make pngstest error limits version specific. Splitting the machine
-    generated error structs out to a file allows the values to be updated
-    without changing pngstest.c itself. Since libpng 1.6 and 1.7 have
-    slightly different error limits this simplifies maintenance. The
-    makepngs.sh script has also been updated to more accurately reflect
-    current problems in libpng 1.7 (John Bowler).
-  Incorporated new test PNG files into make check.  tests/pngstest-*
-    are changed so that the new test files are divided into 8 groups by
-    gamma and alpha channel.  These tests have considerably better code
-    and pixel-value coverage than contrib/pngsuite; however,coverage is
-    still incomplete (John Bowler).
-  Removed the '--strict' in 1.6 because of the double-gamma-correction
-    warning, updated pngstest-errors.h for the errors detected with the
-    new contrib/testspngs PNG test files (John Bowler).
-
-Version 1.6.19beta04 [October 15, 2015]
-  Worked around rgb-to-gray issues in libpng 1.6.  The previous
-    attempts to ignore the errors in the code aren't quite enough to
-    deal with the 'channel selection' encoding added to libpng 1.7; abort.
-    pngvalid.c is changed to drop this encoding in prior versions.
-  Fixed 'pow' macros in pngvalid.c. It is legal for 'pow' to be a
-    macro, therefore the argument list cannot contain preprocessing
-    directives.  Make sure pow is a function where this happens. This is
-    a minimal safe fix, the issue only arises in non-performance-critical
-    code (bug report by Curtis Leach, fix by John Bowler).
-  Added sPLT support to pngtest.c
-
-Version 1.6.19rc01 [October 23, 2015]
-  No changes.
-
-Version 1.6.19rc02 [October 31, 2015]
-  Prevent setting or writing over-length PLTE chunk (Cosmin Truta).
-  Silently truncate over-length PLTE chunk while reading.
-  Libpng incorrectly calculated the output rowbytes when the application
-    decreased either the number of channels or the bit depth (or both) in
-    a user transform.  This was safe; libpng overallocated buffer space
-   (potentially by quite a lot; up to 4 times the amount required) but,
-   from 1.5.4 on, resulted in a png_error (John Bowler).
-
-Version 1.6.19rc03 [November 3, 2015]
-  Fixed some inconsequential cut-and-paste typos in png_set_cHRM_XYZ_fixed().
-  Clarified COPYRIGHT information to state explicitly that versions
-    are derived from previous versions.
-  Removed much of the long list of previous versions from png.h and
-    libpng.3.
-
-Version 1.6.19rc04 [November 5, 2015]
-  Fixed new bug with CRC error after reading an over-length palette
-    (bug report by Cosmin Truta) (CVE-2015-8126).
-
-Version 1.6.19 [November 12, 2015]
-  Cleaned up coding style in png_handle_PLTE().
-
-Version 1.6.20beta01 [November 20, 2015]
-  Avoid potential pointer overflow/underflow in png_handle_sPLT() and
-    png_handle_pCAL() (Bug report by John Regehr).
-
-Version 1.6.20beta02 [November 23, 2015]
-  Fixed incorrect implementation of png_set_PLTE() that uses png_ptr
-    not info_ptr, that left png_set_PLTE() open to the CVE-2015-8126
-    vulnerability.  Fixes CVE-2015-8472.
-
-Version 1.6.20beta03 [November 24, 2015]
-  Backported tests from libpng-1.7.0beta69.
-
-Version 1.6.20rc01 [November 26, 2015]
-  Fixed an error in handling of bad zlib CMINFO field in pngfix, found by
-    American Fuzzy Lop, reported by Brian Carpenter.  inflate() doesn't
-    immediately fault a bad CMINFO field; instead a 'too far back' error
-    happens later (at least some times).  pngfix failed to limit CMINFO to
-    the allowed values but then assumed that window_bits was in range,
-    triggering an assert. The bug is mostly harmless; the PNG file cannot
-    be fixed.
-
-Version 1.6.20rc02 [November 29, 2015]
-  In libpng 1.6 zlib initialization was changed to use the window size
-    in the zlib stream, not a fixed value. This causes some invalid images,
-    where CINFO is too large, to display 'correctly' if the rest of the
-    data is valid.  This provides a workaround for zlib versions where the
-    error arises (ones that support the API change to use the window size
-    in the stream).
-
-Version 1.6.20 [December 3, 2015]
-  No changes.
-
-Version 1.6.21beta01 [December 11, 2015]
-  Fixed syntax "$(command)" in tests/pngstest that some shells other than
-    bash could not parse (Bug report by Nelson Beebe). Use `command` instead.
-
-Version 1.6.21beta02 [December 14, 2015]
-  Moved png_check_keyword() from pngwutil.c to pngset.c
-  Removed LE/BE dependencies in pngvalid, to 'fix' the current problem
-    in the BigEndian tests by not testing it, making the BE code the same 
-    as the LE version.
-  Fixes to pngvalid for various reduced build configurations (eliminate unused
-    statics) and a fix for the case in rgb_to_gray when the digitize option
-    reduces graylo to 0, producing a large error.
-
-Version 1.6.21beta03 [December 18, 2015]
-  Widened the 'limit' check on the internally calculated error limits in
-    the 'DIGITIZE' case (the code used prior to 1.7 for rgb_to_gray error
-    checks) and changed the check to only operate in non-release builds
-    (base build type not RC or RELEASE.)
-  Fixed undefined behavior in pngvalid.c, undefined because
-    (png_byte) << shift is undefined if it changes the signed bit
-    (because png_byte is promoted to int). The libpng exported functions
-    png_get_uint_32 and png_get_uint_16 handle this. (Bug reported by
-    David Drysdale as a result of reports from UBSAN in clang 3.8).
-  This changes pngvalid to use BE random numbers; this used to produce
-    errors but these should not be fixed as a result of the previous changes.
-
-Version 1.6.21rc01 [January 4, 2016]
-  In projects/vstudio, combined readme.txt and WARNING into README.txt
-
-Version 1.6.21rc02 [January 7, 2016]
-  Relocated assert() in contrib/tools/pngfix.c, bug found by American
-    Fuzzy Lop, reported by Brian Carpenter.
-  Marked 'limit' UNUSED in transform_range_check().  This only affects
-    release builds.
-
-Version 1.6.21 [January 15, 2016]
-  Worked around a false-positive Coverity issue in pngvalid.c.
-
-Version 1.6.22beta01 [January 23, 2016]
-  Changed PNG_USE_MKSTEMP to __COVERITY__ to select alternate
-    "tmpfile()" implementation in contrib/libtests/pngstest.c
-  Fixed NO_STDIO build of pngunknown.c to skip calling png_init_io()
-    if there is no stdio.h support.
-  Added a png_image_write_to_memory() API and a number of assist macros
-    to allow an application that uses the simplified API write to bypass
-    stdio and write directly to memory.
-  Added some warnings (png.h) and some check code to detect *possible*
-    overflow in the ROW_STRIDE and simplified image SIZE macros.  This
-    disallows image width/height/format that *might* overflow.  This is
-    a quiet API change that limits in-memory image size (uncompressed) to
-    less than 4GByte and image row size (stride) to less than 2GByte.
-  Revised workaround for false-positive Coverity issue in pngvalid.c.
-
-Version 1.6.22beta02 [February 8, 2016]
-  Only use exit(77) in configure builds.
-  Corrected error in PNG_IMAGE_PNG_SIZE_MAX. This new macro underreported
-    the palette size because it failed to take into account that the memory
-    palette has to be expanded to full RGB when it is written to PNG.
-  Updated CMakeLists.txt, added supporting scripts/gen*.cmake.in
-    and test.cmake.in (Roger Leigh).
-  Relaxed limit checks on gamma values in pngrtran.c. As suggested in
-    the comments gamma values outside the range currently permitted
-    by png_set_alpha_mode are useful for HDR data encoding.  These values
-    are already permitted by png_set_gamma so it is reasonable caution to
-    extend the png_set_alpha_mode range as HDR imaging systems are starting
-    to emerge.
-
-Version 1.6.22beta03 [March 9, 2016]
-  Added a common-law trademark notice and export control information
-    to the LICENSE file, png.h, and the man page.
-  Restored "& 0xff" in png_save_uint_16() and png_save_uint_32() that
-    were accidentally removed from libpng-1.6.17. 
-  Changed PNG_INFO_cHNK and PNG_FREE_cHNK from 0xnnnn to 0xnnnnU in png.h
-    (Robert C. Seacord).
-  Removed dubious "#if INT_MAX" test from png.h that was added to
-    libpng-1.6.19beta02 (John Bowler).
-  Add ${INCLUDES} in scripts/genout.cmake.in (Bug report by Nixon Kwok).
-  Updated LICENSE to say files in the contrib directory are not
-    necessarily under the libpng license, and that some makefiles have
-    other copyright owners.
-  Added INTEL-SSE2 support (Mike Klein and Matt Sarett, Google, Inc.).
-  Made contrib/libtests/timepng more robust.  The code no longer gives
-    up/fails on invalid PNG data, it just skips it (with error messages).
-    The code no longer fails on PNG files with data beyond IEND.  Options
-    exist to use png_read_png (reading the whole image, not by row) and, in
-    that case, to apply any of the supported transforms.  This makes for
-    more realistic testing; the decoded data actually gets used in a
-    meaningful fashion (John Bowler).
-  Fixed some misleading indentation (Krishnaraj Bhat).
-
-Version 1.6.22beta04 [April 5, 2016]
-  Force GCC compilation to C89 if needed (Dagobert Michelsen).
-  SSE filter speed improvements for bpp=3:
-    memcpy-free implementations of load3() / store3().
-    call load3() only when needed at the end of a scanline.
-
-Version 1.6.22beta05 [April 27, 2016]
-  Added PNG_FAST_FILTERS macro (defined as
-    PNG_FILTER_NONE|PNG_FILTER_SUB|PNG_FILTER_UP).
-  Various fixes for contrib/libtests/timepng.c
-  Moved INTEL-SSE code from pngpriv.h into contrib/intel/intel_sse.patch.
-  Fixed typo (missing underscore) in #define PNG_READ_16_TO_8_SUPPORTED
-    (Bug report by Y.Ohashik).
-
-Version 1.6.22beta06 [May 5, 2016]
-  Rebased contrib/intel_sse.patch.
-  Quieted two Coverity issues in contrib/libtests/timepng.c.
-  Fixed issues with scripts/genout.cmake.in (David Capello, Nixon Kwok):
-    Added support to use multiple directories in ZLIBINCDIR variable,
-    Fixed CMAKE_C_FLAGS with multiple values when genout is compiled on MSVC,
-    Fixed pnglibconf.c compilation on OS X including the sysroot path.
-
-Version 1.6.22rc01 [May 14, 2016]
-  No changes.
-
-Version 1.6.22rc02 [May 16, 2016]
-  Removed contrib/timepng from default build; it does not build on platforms
-    that don't supply clock_gettime().
-
-Version 1.6.22rc03 [May 17, 2016]
-  Restored contrib/timepng to default build but check for the presence
-    of clock_gettime() in configure.ac and Makefile.am.
-
-Version 1.6.22 [May 26, 2016]
-  No changes.
-
-Version 1.6.23beta01 [May 29, 2016]
-  Stop a potential memory leak in png_set_tRNS() (Bug report by Ted Ying).
-  Fixed the progressive reader to handle empty first IDAT chunk properly
-    (patch by Timothy Nikkel).  This bug was introduced in libpng-1.6.0 and
-    only affected the libpng16 branch.
-  Added tests in pngvalid.c to check zero-length IDAT chunks in various
-    positions.  Fixed the sequential reader to handle these more robustly
-    (John Bowler).
-
 Send comments/corrections/commendations to png-mng-implement at lists.sf.net
 (subscription required; visit
 https://lists.sourceforge.net/lists/listinfo/png-mng-implement
--- a/CMakeLists.txt
+++ b/CMakeLists.txt
@@ -1,32 +1,13 @@
 # CMakeLists.txt

-# Copyright (C) 2007,2009-2016 Glenn Randers-Pehrson
-# Written by Christian Ehrlicher, 2007
-# Revised by Roger Lowman, 2009-2010
-# Revised by Clifford Yapp, 2011-2012
-# Revised by Roger Leigh, 2016
+# Copyright (C) 2007-2015 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

-cmake_minimum_required(VERSION 2.8.3)
-cmake_policy(VERSION 2.8.3)
-
-# Set MacOSX @rpath usage globally.
-if (POLICY CMP0020)
-  cmake_policy(SET CMP0020 NEW)
-endif(POLICY CMP0020)
-if (POLICY CMP0042)
-  cmake_policy(SET CMP0042 NEW)
-endif(POLICY CMP0042)
-# Use new variable expansion policy.
-if (POLICY CMP0053)
-  cmake_policy(SET CMP0053 NEW)
-endif(POLICY CMP0053)
-if (POLICY CMP0054)
-  cmake_policy(SET CMP0054 NEW)
-endif(POLICY CMP0054)
+cmake_minimum_required(VERSION 2.4.4)
+set(CMAKE_ALLOW_LOOSE_LOOP_CONSTRUCTS true)

 set(CMAKE_CONFIGURATION_TYPES "Release;Debug;MinSizeRel;RelWithDebInfo")

@@ -35,7 +16,7 @@ enable_testing()

 set(PNGLIB_MAJOR 1)
 set(PNGLIB_MINOR 6)
-set(PNGLIB_RELEASE 23)
+set(PNGLIB_RELEASE 18)
 set(PNGLIB_NAME libpng${PNGLIB_MAJOR}${PNGLIB_MINOR})
 set(PNGLIB_VERSION ${PNGLIB_MAJOR}.${PNGLIB_MINOR}.${PNGLIB_RELEASE})

@@ -66,284 +47,32 @@ option(PNG_FRAMEWORK "Build OS X framework" OFF)
 option(PNG_DEBUG     "Build with debug output" OFF)
 option(PNGARG        "Disable ANSI-C prototypes" OFF)

-set(PNG_PREFIX "" CACHE STRING "Prefix to add to the API function names")
-set(DFA_XTRA "" CACHE FILEPATH "File containing extra configuration settings")
-
 # SET LIBNAME
 set(PNG_LIB_NAME png${PNGLIB_MAJOR}${PNGLIB_MINOR})

 # to distinguish between debug and release lib
 set(CMAKE_DEBUG_POSTFIX "d")

-include(CheckCSourceCompiles)
-option(ld-version-script "Enable linker version script" ON)
-if(ld-version-script AND NOT APPLE)
-  # Check if LD supports linker scripts.
-  file(WRITE "${CMAKE_CURRENT_BINARY_DIR}/conftest.map" "VERS_1 {
-        global: sym;
-        local: *;
-};
-
-VERS_2 {
-        global: sym2;
-                main;
-} VERS_1;
-")
-  set(CMAKE_REQUIRED_FLAGS_SAVE ${CMAKE_REQUIRED_FLAGS})
-  set(CMAKE_REQUIRED_FLAGS ${CMAKE_REQUIRED_FLAGS} "-Wl,--version-script='${CMAKE_CURRENT_BINARY_DIR}/conftest.map'")
-  check_c_source_compiles("void sym(void) {}
-void sym2(void) {}
-int main(void) {return 0;}
-" HAVE_LD_VERSION_SCRIPT)
-  if(NOT HAVE_LD_VERSION_SCRIPT)
-    set(CMAKE_REQUIRED_FLAGS ${CMAKE_REQUIRED_FLAGS_SAVE} "-Wl,-M -Wl,${CMAKE_CURRENT_BINARY_DIR}/conftest.map")
-  check_c_source_compiles("void sym(void) {}
-void sym2(void) {}
-int main(void) {return 0;}
-" HAVE_SOLARIS_LD_VERSION_SCRIPT)
-  endif()
-  set(CMAKE_REQUIRED_FLAGS ${CMAKE_REQUIRED_FLAGS_SAVE})
-  file(REMOVE "${CMAKE_CURRENT_BINARY_DIR}/conftest.map")
-endif()
-
-# Find symbol prefix.  Likely obsolete and unnecessary with recent
-# toolchains (it's not done in many other projects).
-function(symbol_prefix)
-  set(SYMBOL_PREFIX)
-
-  execute_process(COMMAND "${CMAKE_C_COMPILER}" "-E" "-"
-                  INPUT_FILE /dev/null
-                  OUTPUT_VARIABLE OUT
-                  RESULT_VARIABLE STATUS)
-
-  if(CPP_FAIL)
-    message(WARNING "Failed to run the C preprocessor")
-  endif()
-
-  string(REPLACE "\n" ";" OUT "${OUT}")
-  foreach(line ${OUT})
-    string(REGEX MATCH "^PREFIX=" found_match "${line}")
-    if(found_match)
-      STRING(REGEX REPLACE "^PREFIX=(.*\)" "\\1" prefix "${line}")
-      string(REGEX MATCH "__USER_LABEL_PREFIX__" found_match "${prefix}")
-      if(found_match)
-        STRING(REGEX REPLACE "(.*)__USER_LABEL_PREFIX__(.*)" "\\1\\2" prefix "${prefix}")
-      endif()
-      set(SYMBOL_PREFIX "${prefix}")
-    endif()
-  endforeach()
-
-    message(STATUS "Symbol prefix: ${SYMBOL_PREFIX}")
-    set(SYMBOL_PREFIX "${SYMBOL_PREFIX}" PARENT_SCOPE)
-endfunction()
-
-if(UNIX)
-  symbol_prefix()
-endif()
-
-find_program(AWK NAMES gawk awk)
-
+# Use the prebuilt pnglibconf.h file from the scripts folder
+# TODO: fix this by building with awk; without this no cmake build can be
+# configured directly (to do so indirectly use your local awk to build a
+# pnglibconf.h in the build directory.)
+configure_file(${CMAKE_CURRENT_SOURCE_DIR}/scripts/pnglibconf.h.prebuilt
+               ${CMAKE_CURRENT_BINARY_DIR}/pnglibconf.h)
 include_directories(${CMAKE_CURRENT_BINARY_DIR})

-if(NOT AWK)
-  # No awk available to generate sources; use pre-built pnglibconf.h
-  configure_file(${CMAKE_CURRENT_SOURCE_DIR}/scripts/pnglibconf.h.prebuilt
-                 ${CMAKE_CURRENT_BINARY_DIR}/pnglibconf.h)
-  add_custom_target(genfiles) # Dummy
-else()
-  include(CMakeParseArguments)
-  # Generate .chk from .out with awk
-  # generate_chk(INPUT inputfile OUTPUT outputfile [DEPENDS dep1 [dep2...]])
-  function(generate_chk)
-    set(options)
-    set(oneValueArgs INPUT OUTPUT)
-    set(multiValueArgs DEPENDS)
-    cmake_parse_arguments(_GC "${options}" "${oneValueArgs}" "${multiValueArgs}" ${ARGN})
-    if (NOT _GC_INPUT)
-      message(FATAL_ERROR "Invalid arguments.  generate_out requires input.")
-    endif()
-    if (NOT _GC_OUTPUT)
-      message(FATAL_ERROR "Invalid arguments.  generate_out requires output.")
-    endif()
-
-    add_custom_command(OUTPUT "${_GC_OUTPUT}"
-                       COMMAND "${CMAKE_COMMAND}"
-                               "-DINPUT=${_GC_INPUT}"
-                               "-DOUTPUT=${_GC_OUTPUT}"
-                               -P "${CMAKE_CURRENT_BINARY_DIR}/scripts/genchk.cmake"
-                       DEPENDS "${_GC_INPUT}" ${_GC_DEPENDS}
-                       WORKING_DIRECTORY "${CMAKE_CURRENT_BINARY_DIR}")
-  endfunction()
-
-  # Generate .out from .c with awk
-  # generate_out(INPUT inputfile OUTPUT outputfile [DEPENDS dep1 [dep2...]])
-  function(generate_out)
-    set(options)
-    set(oneValueArgs INPUT OUTPUT)
-    set(multiValueArgs DEPENDS)
-    cmake_parse_arguments(_GO "${options}" "${oneValueArgs}" "${multiValueArgs}" ${ARGN})
-    if (NOT _GO_INPUT)
-      message(FATAL_ERROR "Invalid arguments.  generate_out requires input.")
-    endif()
-    if (NOT _GO_OUTPUT)
-      message(FATAL_ERROR "Invalid arguments.  generate_out requires output.")
-    endif()
-
-    add_custom_command(OUTPUT "${_GO_OUTPUT}"
-                       COMMAND "${CMAKE_COMMAND}"
-                               "-DINPUT=${_GO_INPUT}"
-                               "-DOUTPUT=${_GO_OUTPUT}"
-                               -P "${CMAKE_CURRENT_BINARY_DIR}/scripts/genout.cmake"
-                       DEPENDS "${_GO_INPUT}" ${_GO_DEPENDS}
-                       WORKING_DIRECTORY "${CMAKE_CURRENT_BINARY_DIR}")
-  endfunction()
-
-  # Generate specific source file with awk
-  # generate_source(OUTPUT outputfile [DEPENDS dep1 [dep2...]])
-  function(generate_source)
-    set(options)
-    set(oneValueArgs OUTPUT)
-    set(multiValueArgs DEPENDS)
-    cmake_parse_arguments(_GSO "${options}" "${oneValueArgs}" "${multiValueArgs}" ${ARGN})
-    if (NOT _GSO_OUTPUT)
-      message(FATAL_ERROR "Invalid arguments.  generate_source requires output.")
-    endif()
-
-    add_custom_command(OUTPUT "${CMAKE_CURRENT_BINARY_DIR}/${_GSO_OUTPUT}"
-                       COMMAND "${CMAKE_COMMAND}"
-                               "-DOUTPUT=${_GSO_OUTPUT}"
-                               -P "${CMAKE_CURRENT_BINARY_DIR}/scripts/gensrc.cmake"
-                       DEPENDS ${_GSO_DEPENDS}
-                       WORKING_DIRECTORY "${CMAKE_CURRENT_BINARY_DIR}")
-  endfunction()
-
-  # Copy file
-  function(generate_copy source destination)
-    add_custom_command(OUTPUT "${destination}"
-                       COMMAND "${CMAKE_COMMAND}" -E remove "${destination}"
-                       COMMAND "${CMAKE_COMMAND}" -E copy "${source}"
-                                                          "${destination}"
-                       DEPENDS "${source}")
-  endfunction()
-
-  # Generate scripts/pnglibconf.h
-  generate_source(OUTPUT "scripts/pnglibconf.c"
-                  DEPENDS "${CMAKE_CURRENT_SOURCE_DIR}/scripts/pnglibconf.dfa"
-                          "${CMAKE_CURRENT_SOURCE_DIR}/scripts/options.awk"
-                          "${CMAKE_CURRENT_SOURCE_DIR}/pngconf.h")
-
-  # Generate pnglibconf.c
-  generate_source(OUTPUT "pnglibconf.c"
-                  DEPENDS "${CMAKE_CURRENT_SOURCE_DIR}/scripts/pnglibconf.dfa"
-                          "${CMAKE_CURRENT_SOURCE_DIR}/scripts/options.awk"
-                          "${CMAKE_CURRENT_SOURCE_DIR}/pngconf.h")
-
-  if(PNG_PREFIX)
-    set(PNGLIBCONF_H_EXTRA_DEPENDS
-        "${CMAKE_CURRENT_BINARY_DIR}/scripts/prefix.out"
-        "${CMAKE_CURRENT_SOURCE_DIR}/scripts/macro.lst")
-    set(PNGPREFIX_H_EXTRA_DEPENDS
-        "${CMAKE_CURRENT_BINARY_DIR}/scripts/intprefix.out")
-  endif()
-
-  generate_out(INPUT "${CMAKE_CURRENT_BINARY_DIR}/pnglibconf.c"
-               OUTPUT "${CMAKE_CURRENT_BINARY_DIR}/pnglibconf.out")
-
-  # Generate pnglibconf.h
-  generate_source(OUTPUT "pnglibconf.h"
-                  DEPENDS "${CMAKE_CURRENT_BINARY_DIR}/pnglibconf.out"
-                          ${PNGLIBCONF_H_EXTRA_DEPENDS})
-
-  generate_out(INPUT "${CMAKE_CURRENT_SOURCE_DIR}/scripts/intprefix.c"
-               OUTPUT "${CMAKE_CURRENT_BINARY_DIR}/scripts/intprefix.out"
-               DEPENDS "${CMAKE_CURRENT_BINARY_DIR}/pnglibconf.h")
-
-  generate_out(INPUT "${CMAKE_CURRENT_SOURCE_DIR}/scripts/prefix.c"
-               OUTPUT "${CMAKE_CURRENT_BINARY_DIR}/scripts/prefix.out"
-               DEPENDS "${CMAKE_CURRENT_SOURCE_DIR}/png.h"
-                       "${CMAKE_CURRENT_SOURCE_DIR}/pngconf.h"
-                       "${CMAKE_CURRENT_BINARY_DIR}/pnglibconf.out")
-
-  # Generate pngprefix.h
-  generate_source(OUTPUT "pngprefix.h"
-                  DEPENDS ${PNGPREFIX_H_EXTRA_DEPENDS})
-
-  generate_out(INPUT "${CMAKE_CURRENT_SOURCE_DIR}/scripts/sym.c"
-               OUTPUT "${CMAKE_CURRENT_BINARY_DIR}/scripts/sym.out"
-               DEPENDS "${CMAKE_CURRENT_BINARY_DIR}/pnglibconf.h")
-
-  generate_out(INPUT "${CMAKE_CURRENT_SOURCE_DIR}/scripts/symbols.c"
-               OUTPUT "${CMAKE_CURRENT_BINARY_DIR}/scripts/symbols.out"
-               DEPENDS "${CMAKE_CURRENT_SOURCE_DIR}/png.h"
-                       "${CMAKE_CURRENT_SOURCE_DIR}/pngconf.h"
-                       "${CMAKE_CURRENT_SOURCE_DIR}/scripts/pnglibconf.h.prebuilt")
-
-  generate_out(INPUT "${CMAKE_CURRENT_SOURCE_DIR}/scripts/vers.c"
-               OUTPUT "${CMAKE_CURRENT_BINARY_DIR}/scripts/vers.out"
-               DEPENDS "${CMAKE_CURRENT_SOURCE_DIR}/png.h"
-                       "${CMAKE_CURRENT_SOURCE_DIR}/pngconf.h"
-                       "${CMAKE_CURRENT_BINARY_DIR}/pnglibconf.h")
-
-  generate_chk(INPUT "${CMAKE_CURRENT_BINARY_DIR}/scripts/symbols.out"
-               OUTPUT "${CMAKE_CURRENT_BINARY_DIR}/scripts/symbols.chk"
-               DEPENDS "${CMAKE_CURRENT_SOURCE_DIR}/scripts/checksym.awk"
-                       "${CMAKE_CURRENT_SOURCE_DIR}/scripts/symbols.def")
-
-  add_custom_target(symbol-check DEPENDS
-                    "${CMAKE_CURRENT_BINARY_DIR}/scripts/symbols.chk")
-
-  generate_copy("${CMAKE_CURRENT_BINARY_DIR}/scripts/sym.out"
-                "${CMAKE_CURRENT_BINARY_DIR}/libpng.sym")
-  generate_copy("${CMAKE_CURRENT_BINARY_DIR}/scripts/vers.out"
-                "${CMAKE_CURRENT_BINARY_DIR}/libpng.vers")
-
-  add_custom_target(genvers DEPENDS "${CMAKE_CURRENT_BINARY_DIR}/libpng.vers")
-  add_custom_target(gensym DEPENDS "${CMAKE_CURRENT_BINARY_DIR}/libpng.sym")
-
-  add_custom_target("genprebuilt"
-                    COMMAND "${CMAKE_COMMAND}"
-                            "-DOUTPUT=scripts/pnglibconf.h.prebuilt"
-                            -P "${CMAKE_CURRENT_BINARY_DIR}/scripts/gensrc.cmake"
-                    WORKING_DIRECTORY "${CMAKE_CURRENT_BINARY_DIR}")
-
-  # A single target handles generation of all generated files.  If
-  # they are dependend upon separately by multiple targets, this
-  # confuses parallel make (it would require a separate top-level
-  # target for each file to track the dependencies properly).
-  add_custom_target(genfiles DEPENDS
-    "${CMAKE_CURRENT_BINARY_DIR}/libpng.sym"
-    "${CMAKE_CURRENT_BINARY_DIR}/libpng.vers"
-    "${CMAKE_CURRENT_BINARY_DIR}/pnglibconf.c"
-    "${CMAKE_CURRENT_BINARY_DIR}/pnglibconf.h"
-    "${CMAKE_CURRENT_BINARY_DIR}/pnglibconf.out"
-    "${CMAKE_CURRENT_BINARY_DIR}/pngprefix.h"
-    "${CMAKE_CURRENT_BINARY_DIR}/scripts/intprefix.out"
-    "${CMAKE_CURRENT_BINARY_DIR}/scripts/pnglibconf.c"
-    "${CMAKE_CURRENT_BINARY_DIR}/scripts/prefix.out"
-    "${CMAKE_CURRENT_BINARY_DIR}/scripts/sym.out"
-    "${CMAKE_CURRENT_BINARY_DIR}/scripts/symbols.chk"
-    "${CMAKE_CURRENT_BINARY_DIR}/scripts/symbols.out"
-    "${CMAKE_CURRENT_BINARY_DIR}/scripts/vers.out")
-endif(NOT AWK)
-
 # OUR SOURCES
 set(libpng_public_hdrs
  png.h
  pngconf.h
-  "${CMAKE_CURRENT_BINARY_DIR}/pnglibconf.h"
+  ${CMAKE_CURRENT_BINARY_DIR}/pnglibconf.h
 )
-set(libpng_private_hdrs
-  pngpriv.h
-  pngdebug.h
-  pnginfo.h
-  pngstruct.h
-)
-if(AWK)
-  list(APPEND libpng_private_hdrs "${CMAKE_CURRENT_BINARY_DIR}/pngprefix.h")
-endif()
 set(libpng_sources
  ${libpng_public_hdrs}
-  ${libpng_private_hdrs}
+  pngdebug.h
+  pnginfo.h
+  pngpriv.h
+  pngstruct.h
  png.c
  pngerror.c
  pngget.c
@@ -369,18 +98,7 @@ set(pngvalid_sources
 set(pngstest_sources
  contrib/libtests/pngstest.c
 )
-set(pngunknown_sources
-  contrib/libtests/pngunknown.c
-)
-set(pngimage_sources
-  contrib/libtests/pngimage.c
-)
-set(pngfix_sources
-  contrib/tools/pngfix.c
-)
-set(png_fix_itxt_sources
-  contrib/tools/png-fix-itxt.c
-)
+# SOME NEEDED DEFINITIONS

 if(MSVC)
  add_definitions(-D_CRT_SECURE_NO_DEPRECATE)
@@ -396,59 +114,33 @@ include_directories(${CMAKE_CURRENT_SOURCE_DIR} ${ZLIB_INCLUDE_DIR})
 unset(PNG_LIB_TARGETS)

 if(PNG_SHARED)
-  add_library(png SHARED ${libpng_sources})
-  set(PNG_LIB_TARGETS png)
-  set_target_properties(png PROPERTIES OUTPUT_NAME ${PNG_LIB_NAME})
-  add_dependencies(png genfiles)
+  add_library(${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 PROPERTIES PREFIX "lib")
-    set_target_properties(png PROPERTIES IMPORT_PREFIX "lib")
-  endif()
-  target_link_libraries(png ${ZLIB_LIBRARY} ${M_LIBRARY})
-
-  if(UNIX AND AWK)
-    if(HAVE_LD_VERSION_SCRIPT)
-      set_target_properties(png PROPERTIES LINK_FLAGS
-        "-Wl,--version-script='${CMAKE_CURRENT_BINARY_DIR}/libpng.vers'")
-    elseif(HAVE_SOLARIS_LD_VERSION_SCRIPT)
-      set_target_properties(png PROPERTIES LINK_FLAGS
-        "-Wl,-M -Wl,'${CMAKE_CURRENT_BINARY_DIR}/libpng.vers'")
-    endif()
+    set_target_properties(${PNG_LIB_NAME} PROPERTIES PREFIX "lib")
+    set_target_properties(${PNG_LIB_NAME} PROPERTIES IMPORT_PREFIX "lib")
  endif()
+  target_link_libraries(${PNG_LIB_NAME} ${ZLIB_LIBRARY} ${M_LIBRARY})
 endif()

 if(PNG_STATIC)
  # does not work without changing name
-  set(PNG_LIB_NAME_STATIC png_static)
-  add_library(png_static STATIC ${libpng_sources})
-  add_dependencies(png_static genfiles)
-  # MSVC doesn't use a different file extension for shared vs. static
-  # libs.  We are able to change OUTPUT_NAME to remove the _static
-  # for all other platforms.
-  if(NOT MSVC)
-    set_target_properties(png_static PROPERTIES
-      OUTPUT_NAME "${PNG_LIB_NAME}"
-      CLEAN_DIRECT_OUTPUT 1)
-  else()
-    set_target_properties(png_static PROPERTIES
-      OUTPUT_NAME "${PNG_LIB_NAME}_static"
-      CLEAN_DIRECT_OUTPUT 1)
-  endif()
-  list(APPEND PNG_LIB_TARGETS png_static)
+  set(PNG_LIB_NAME_STATIC ${PNG_LIB_NAME}_static)
+  add_library(${PNG_LIB_NAME_STATIC} STATIC ${libpng_sources})
+  list(APPEND PNG_LIB_TARGETS ${PNG_LIB_NAME_STATIC})
  if(MSVC)
    # msvc does not append 'lib' - do it here to have consistent name
-    set_target_properties(png_static PROPERTIES PREFIX "lib")
+    set_target_properties(${PNG_LIB_NAME_STATIC} PROPERTIES PREFIX "lib")
  endif()
-  target_link_libraries(png_static ${ZLIB_LIBRARY} ${M_LIBRARY})
+  target_link_libraries(${PNG_LIB_NAME_STATIC} ${ZLIB_LIBRARY} ${M_LIBRARY})
 endif()

 if(PNG_FRAMEWORK)
-  set(PNG_LIB_NAME_FRAMEWORK png_framework)
-  add_library(png_framework SHARED ${libpng_sources})
-  add_dependencies(png_framework genfiles)
-  list(APPEND PNG_LIB_TARGETS png_framework)
-  set_target_properties(png_framework PROPERTIES
+  set(PNG_LIB_NAME_FRAMEWORK ${PNG_LIB_NAME}_framework)
+  add_library(${PNG_LIB_NAME_FRAMEWORK} SHARED ${libpng_sources})
+  list(APPEND PNG_LIB_TARGETS ${PNG_LIB_NAME_FRAMEWORK})
+  set_target_properties(${PNG_LIB_NAME_FRAMEWORK} PROPERTIES
    FRAMEWORK TRUE
    FRAMEWORK_VERSION ${PNGLIB_VERSION}
    MACOSX_FRAMEWORK_SHORT_VERSION_STRING ${PNGLIB_MAJOR}.${PNGLIB_MINOR}
@@ -457,7 +149,7 @@ if(PNG_FRAMEWORK)
    XCODE_ATTRIBUTE_INSTALL_PATH "@rpath"
    PUBLIC_HEADER "${libpng_public_hdrs}"
    OUTPUT_NAME png)
-  target_link_libraries(png_framework ${ZLIB_LIBRARY} ${M_LIBRARY})
+  target_link_libraries(${PNG_LIB_NAME_FRAMEWORK} ${ZLIB_LIBRARY} ${M_LIBRARY})
 endif()

 if(NOT PNG_LIB_TARGETS)
@@ -468,170 +160,52 @@ if(NOT PNG_LIB_TARGETS)
 endif()

 if(PNG_SHARED AND WIN32)
-  set_target_properties(png PROPERTIES DEFINE_SYMBOL PNG_BUILD_DLL)
+  set_target_properties(${PNG_LIB_NAME} PROPERTIES DEFINE_SYMBOL PNG_BUILD_DLL)
 endif()

-function(png_add_test)
-  set(options)
-  set(oneValueArgs NAME COMMAND)
-  set(multiValueArgs OPTIONS FILES)
-  cmake_parse_arguments(_PAT "${options}" "${oneValueArgs}" "${multiValueArgs}" ${ARGN})
-
-  if (NOT _PAT_NAME)
-    message(FATAL_ERROR "Invalid arguments.  png_add_test requires name.")
-  endif()
-  if (NOT _PAT_COMMAND)
-    message(FATAL_ERROR "Invalid arguments.  png_add_test requires command.")
-  endif()
-
-  set(TEST_OPTIONS "${_PAT_OPTIONS}")
-  set(TEST_FILES "${_PAT_FILES}")
-
-  configure_file("${CMAKE_CURRENT_SOURCE_DIR}/scripts/test.cmake.in"
-                 "${CMAKE_CURRENT_BINARY_DIR}/tests/${_PAT_NAME}.cmake" @ONLY)
-  if(CMAKE_MAJOR_VERSION GREATER 2) # have generator expressions
-    add_test(NAME "${_PAT_NAME}"
-             COMMAND "${CMAKE_COMMAND}"
-             "-DLIBPNG=$<TARGET_FILE:png>"
-             "-DTEST_COMMAND=$<TARGET_FILE:${_PAT_COMMAND}>"
-             -P "${CMAKE_CURRENT_BINARY_DIR}/tests/${_PAT_NAME}.cmake")
-  else() # old 2.x add_test; limited and won't work well on Windows
-    # Note LIBPNG is a dummy value as there are no generator expressions
-    add_test("${_PAT_NAME}" "${CMAKE_COMMAND}"
-             "-DLIBPNG=${CMAKE_CURRENT_BINARY_DIR}/libpng.so"
-             "-DTEST_COMMAND=./${_PAT_COMMAND}"
-             -P "${CMAKE_CURRENT_BINARY_DIR}/tests/${_PAT_NAME}.cmake")
-  endif()
-endfunction()
-
 if(PNG_TESTS AND PNG_SHARED)
-  # Find test PNG files by globbing, but sort lists to ensure
-  # consistency between different filesystems.
-  file(GLOB PNGSUITE_PNGS "${CMAKE_CURRENT_SOURCE_DIR}/contrib/pngsuite/*.png")
-  list(SORT PNGSUITE_PNGS)
-  file(GLOB TEST_PNGS "${CMAKE_CURRENT_SOURCE_DIR}/contrib/testpngs/*.png")
-  list(SORT TEST_PNGS)
-
-  set(PNGTEST_PNG "${CMAKE_CURRENT_SOURCE_DIR}/pngtest.png")
-
+  # does not work with msvc due to png_lib_ver issue
  add_executable(pngtest ${pngtest_sources})
-  target_link_libraries(pngtest png)
-
-  png_add_test(NAME pngtest COMMAND pngtest FILES "${PNGTEST_PNG}")
-
+  target_link_libraries(pngtest ${PNG_LIB_NAME})
+  add_test(pngtest ./pngtest ${CMAKE_CURRENT_SOURCE_DIR}/pngtest.png)
+  #
  add_executable(pngvalid ${pngvalid_sources})
-  target_link_libraries(pngvalid png)
-
-  png_add_test(NAME pngvalid-gamma-16-to-8
-               COMMAND pngvalid OPTIONS --gamma-16-to-8)
-  png_add_test(NAME pngvalid-gamma-alpha-mode
-               COMMAND pngvalid OPTIONS --gamma-alpha-mode)
-  png_add_test(NAME pngvalid-gamma-background
-               COMMAND pngvalid OPTIONS --gamma-background)
-  png_add_test(NAME pngvalid-gamma-expand16-alpha-mode
-               COMMAND pngvalid OPTIONS --gamma-alpha-mode --expand16)
-  png_add_test(NAME pngvalid-gamma-expand16-background
-               COMMAND pngvalid OPTIONS --gamma-background --expand16)
-  png_add_test(NAME pngvalid-gamma-expand16-transform
-               COMMAND pngvalid OPTIONS --gamma-transform --expand16)
-  png_add_test(NAME pngvalid-gamma-sbit
-               COMMAND pngvalid OPTIONS --gamma-sbit)
-  png_add_test(NAME pngvalid-gamma-threshold
-               COMMAND pngvalid OPTIONS --gamma-threshold)
-  png_add_test(NAME pngvalid-gamma-transform
-               COMMAND pngvalid OPTIONS --gamma-transform)
-  png_add_test(NAME pngvalid-progressive-interlace-standard
-               COMMAND pngvalid OPTIONS --standard --progressive-read --interlace)
-  png_add_test(NAME pngvalid-progressive-size
-               COMMAND pngvalid OPTIONS --size --progressive-read)
-  png_add_test(NAME pngvalid-progressive-standard
-               COMMAND pngvalid OPTIONS --standard --progressive-read)
-  png_add_test(NAME pngvalid-standard
-               COMMAND pngvalid OPTIONS --standard)
-  png_add_test(NAME pngvalid-transform
-               COMMAND pngvalid OPTIONS --transform)
-
+  target_link_libraries(pngvalid ${PNG_LIB_NAME})
+  add_test(pngvalid ./pngvalid)
  add_executable(pngstest ${pngstest_sources})
-  target_link_libraries(pngstest png)
-
-  foreach(gamma_type 1.8 linear none sRGB)
-    foreach(alpha_type none alpha)
-      set(PNGSTEST_FILES)
-      foreach(test_png ${TEST_PNGS})
-        string(REGEX MATCH ".*-linear[-.].*" TEST_PNG_LINEAR "${test_png}")
-        string(REGEX MATCH ".*-sRGB[-.].*" TEST_PNG_SRGB "${test_png}")
-        string(REGEX MATCH ".*-1.8[-.].*" TEST_PNG_G18 "${test_png}")
-        string(REGEX MATCH ".*-alpha-.*" TEST_PNG_ALPHA "${test_png}")
-
-        set(TEST_PNG_VALID TRUE)
-
-        if(TEST_PNG_ALPHA)
-          if (NOT "${alpha_type}" STREQUAL "alpha")
-            set(TEST_PNG_VALID FALSE)
-          endif()
-        else()
-          if ("${alpha_type}" STREQUAL "alpha")
-            set(TEST_PNG_VALID FALSE)
-          endif()
-        endif()
-
-        if(TEST_PNG_LINEAR)
-          if(NOT "${gamma_type}" STREQUAL "linear")
-            set(TEST_PNG_VALID FALSE)
-          endif()
-        elseif(TEST_PNG_SRGB)
-          if(NOT "${gamma_type}" STREQUAL "sRGB")
-            set(TEST_PNG_VALID FALSE)
-          endif()
-        elseif(TEST_PNG_G18)
-          if(NOT "${gamma_type}" STREQUAL "1.8")
-            set(TEST_PNG_VALID FALSE)
-          endif()
-        else()
-          if(NOT "${gamma_type}" STREQUAL "none")
-            set(TEST_PNG_VALID FALSE)
-          endif()
-        endif()
-
-        if(TEST_PNG_VALID)
-          list(APPEND PNGSTEST_FILES "${test_png}")
-        endif()
-      endforeach()
-      # Should already be sorted, but sort anyway to be certain.
-      list(SORT PNGSTEST_FILES)
-      png_add_test(NAME pngstest-${gamma_type}-${alpha_type}
-                   COMMAND pngstest
-                   OPTIONS --tmpfile "${gamma_type}-${alpha_type}-" --log
-                   FILES ${PNGSTEST_FILES})
-    endforeach()
-  endforeach()
-
-  add_executable(pngunknown ${pngunknown_sources})
-  target_link_libraries(pngunknown png)
-
-  png_add_test(NAME pngunknown-discard COMMAND pngunknown OPTIONS --strict default=discard FILES "${PNGTEST_PNG}")
-  png_add_test(NAME pngunknown-IDAT COMMAND pngunknown OPTIONS --strict default=discard IDAT=save FILES "${PNGTEST_PNG}")
-  png_add_test(NAME pngunknown-if-safe COMMAND pngunknown OPTIONS --strict default=if-safe FILES "${PNGTEST_PNG}")
-  png_add_test(NAME pngunknown-sAPI COMMAND pngunknown OPTIONS --strict bKGD=save cHRM=save gAMA=save all=discard iCCP=save sBIT=save sRGB=save FILES "${PNGTEST_PNG}")
-  png_add_test(NAME pngunknown-save COMMAND pngunknown OPTIONS --strict default=save FILES "${PNGTEST_PNG}")
-  png_add_test(NAME pngunknown-sTER COMMAND pngunknown OPTIONS --strict sTER=if-safe FILES "${PNGTEST_PNG}")
-  png_add_test(NAME pngunknown-vpAg COMMAND pngunknown OPTIONS --strict vpAg=if-safe FILES "${PNGTEST_PNG}")
-
-  add_executable(pngimage ${pngimage_sources})
-  target_link_libraries(pngimage png)
-
-  png_add_test(NAME pngimage-quick COMMAND pngimage OPTIONS --list-combos --log FILES ${PNGSUITE_PNGS})
-  png_add_test(NAME pngimage-full COMMAND pngimage OPTIONS --exhaustive --list-combos --log FILES ${PNGSUITE_PNGS})
-endif()
-
-if(PNG_SHARED)
-  add_executable(pngfix ${pngfix_sources})
-  target_link_libraries(pngfix png)
-  set(PNG_BIN_TARGETS pngfix)
-
-  add_executable(png-fix-itxt ${png_fix_itxt_sources})
-  target_link_libraries(png-fix-itxt ${ZLIB_LIBRARY} ${M_LIBRARY})
-  list(APPEND PNG_BIN_TARGETS png-fix-itxt)
+  target_link_libraries(pngstest ${PNG_LIB_NAME})
+  add_test(pngstest ./pngstest
+    ${CMAKE_CURRENT_SOURCE_DIR}/contrib/pngsuite/basn0g01.png
+    ${CMAKE_CURRENT_SOURCE_DIR}/contrib/pngsuite/basn0g02.png
+    ${CMAKE_CURRENT_SOURCE_DIR}/contrib/pngsuite/basn0g04.png
+    ${CMAKE_CURRENT_SOURCE_DIR}/contrib/pngsuite/basn0g08.png
+    ${CMAKE_CURRENT_SOURCE_DIR}/contrib/pngsuite/basn0g16.png
+    ${CMAKE_CURRENT_SOURCE_DIR}/contrib/pngsuite/basn2c08.png
+    ${CMAKE_CURRENT_SOURCE_DIR}/contrib/pngsuite/basn2c16.png
+    ${CMAKE_CURRENT_SOURCE_DIR}/contrib/pngsuite/basn3p01.png
+    ${CMAKE_CURRENT_SOURCE_DIR}/contrib/pngsuite/basn3p02.png
+    ${CMAKE_CURRENT_SOURCE_DIR}/contrib/pngsuite/basn3p04.png
+    ${CMAKE_CURRENT_SOURCE_DIR}/contrib/pngsuite/basn3p08.png
+    ${CMAKE_CURRENT_SOURCE_DIR}/contrib/pngsuite/basn4a08.png
+    ${CMAKE_CURRENT_SOURCE_DIR}/contrib/pngsuite/basn4a16.png
+    ${CMAKE_CURRENT_SOURCE_DIR}/contrib/pngsuite/basn6a08.png
+    ${CMAKE_CURRENT_SOURCE_DIR}/contrib/pngsuite/basn6a16.png
+    ${CMAKE_CURRENT_SOURCE_DIR}/contrib/pngsuite/ftbbn0g01.png
+    ${CMAKE_CURRENT_SOURCE_DIR}/contrib/pngsuite/ftbbn0g02.png
+    ${CMAKE_CURRENT_SOURCE_DIR}/contrib/pngsuite/ftbbn0g04.png
+    ${CMAKE_CURRENT_SOURCE_DIR}/contrib/pngsuite/ftbbn2c16.png
+    ${CMAKE_CURRENT_SOURCE_DIR}/contrib/pngsuite/ftbbn3p08.png
+    ${CMAKE_CURRENT_SOURCE_DIR}/contrib/pngsuite/ftbgn2c16.png
+    ${CMAKE_CURRENT_SOURCE_DIR}/contrib/pngsuite/ftbgn3p08.png
+    ${CMAKE_CURRENT_SOURCE_DIR}/contrib/pngsuite/ftbrn2c08.png
+    ${CMAKE_CURRENT_SOURCE_DIR}/contrib/pngsuite/ftbwn0g16.png
+    ${CMAKE_CURRENT_SOURCE_DIR}/contrib/pngsuite/ftbwn3p08.png
+    ${CMAKE_CURRENT_SOURCE_DIR}/contrib/pngsuite/ftbyn3p08.png
+    ${CMAKE_CURRENT_SOURCE_DIR}/contrib/pngsuite/ftp0n0g08.png
+    ${CMAKE_CURRENT_SOURCE_DIR}/contrib/pngsuite/ftp0n2c08.png
+    ${CMAKE_CURRENT_SOURCE_DIR}/contrib/pngsuite/ftp0n3p08.png
+    ${CMAKE_CURRENT_SOURCE_DIR}/contrib/pngsuite/ftp1n3p08.png
+  )
 endif()

 # Ensure the CMAKE_LIBRARY_OUTPUT_DIRECTORY is set
@@ -660,15 +234,6 @@ macro(CREATE_SYMLINK SRC_FILE DEST_FILE)
  endif(WIN32 AND NOT CYGWIN AND NOT MSYS)
 endmacro()

-# Create source generation scripts.
-configure_file(${CMAKE_CURRENT_SOURCE_DIR}/scripts/genchk.cmake.in
-               ${CMAKE_CURRENT_BINARY_DIR}/scripts/genchk.cmake @ONLY)
-configure_file(${CMAKE_CURRENT_SOURCE_DIR}/scripts/genout.cmake.in
-               ${CMAKE_CURRENT_BINARY_DIR}/scripts/genout.cmake @ONLY)
-configure_file(${CMAKE_CURRENT_SOURCE_DIR}/scripts/gensrc.cmake.in
-               ${CMAKE_CURRENT_BINARY_DIR}/scripts/gensrc.cmake @ONLY)
-
-
 # libpng is a library so default to 'lib'
 if(NOT DEFINED CMAKE_INSTALL_LIBDIR)
  set(CMAKE_INSTALL_LIBDIR lib)
@@ -695,12 +260,22 @@ endif(NOT WIN32 OR CYGWIN OR MINGW)

 # SET UP LINKS
 if(PNG_SHARED)
-  set_target_properties(png PROPERTIES
-#   VERSION 16.${PNGLIB_RELEASE}.1.6.23beta01
+  set_target_properties(${PNG_LIB_NAME} PROPERTIES
+#   VERSION 16.${PNGLIB_RELEASE}.1.6.18
    VERSION 16.${PNGLIB_RELEASE}.0
    SOVERSION 16
    CLEAN_DIRECT_OUTPUT 1)
 endif()
+if(PNG_STATIC)
+  # MSVC doesn't use a different file extension for shared vs. static
+  # libs.  We are able to change OUTPUT_NAME to remove the _static
+  # for all other platforms.
+  if(NOT MSVC)
+    set_target_properties(${PNG_LIB_NAME_STATIC} PROPERTIES
+      OUTPUT_NAME ${PNG_LIB_NAME}
+      CLEAN_DIRECT_OUTPUT 1)
+  endif()
+endif()

 # If CMake > 2.4.x, we set a variable used below to export
 # targets to an export file.
@@ -723,14 +298,14 @@ if(NOT SKIP_INSTALL_LIBRARIES AND NOT SKIP_INSTALL_ALL )
  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 LOCATION_${CMAKE_BUILD_TYPE})
+       get_target_property(BUILD_TARGET_LOCATION ${PNG_LIB_NAME} LOCATION_${CMAKE_BUILD_TYPE})
       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 LOCATION_${CMAKE_BUILD_TYPE})
+      get_target_property(BUILD_TARGET_LOCATION ${PNG_LIB_NAME} LOCATION_${CMAKE_BUILD_TYPE})
      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})
@@ -739,7 +314,7 @@ if(NOT SKIP_INSTALL_LIBRARIES AND NOT SKIP_INSTALL_ALL )

  if(PNG_STATIC)
    if(NOT WIN32 OR CYGWIN OR MINGW)
-      get_target_property(BUILD_TARGET_LOCATION png_static LOCATION_${CMAKE_BUILD_TYPE})
+      get_target_property(BUILD_TARGET_LOCATION ${PNG_LIB_NAME_STATIC} LOCATION_${CMAKE_BUILD_TYPE})
      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})
@@ -759,11 +334,6 @@ if(NOT SKIP_INSTALL_EXECUTABLES AND NOT SKIP_INSTALL_ALL )
  endif(NOT WIN32 OR CYGWIN OR MINGW)
 endif()

-if(NOT SKIP_INSTALL_PROGRAMS AND NOT SKIP_INSTALL_ALL )
-  install(TARGETS ${PNG_BIN_TARGETS}
-      RUNTIME DESTINATION bin)
-endif()
-
 if(NOT SKIP_INSTALL_FILES AND NOT SKIP_INSTALL_ALL )
  # Install man pages
  if(NOT PNG_MAN_DIR)
--- a/4
+++ b/4
@@ -47,9 +47,7 @@ If configure does not work on your system, or if you have a need to
 change configure.ac or Makefile.am, and you have a reasonably
 up-to-date set of tools, running ./autogen.sh in a git clone before
 running ./configure may fix the problem.  To be really sure that you
-aren't using any of the included pre-built scripts, especially if you
-are building from a tar distribution instead of a git distribution,
-do this:
+aren't using any of the included pre-built scripts, you can do this:

    ./configure --enable-maintainer-mode
    make maintainer-clean
--- a/55
+++ b/55
@@ -10,11 +10,10 @@ this sentence.

 This code is released under the libpng license.

-libpng versions 1.0.7, July 1, 2000 through 1.6.23beta01, May 29, 2016 are
-Copyright (c) 2000-2002, 2004, 2006-2016 Glenn Randers-Pehrson, are
-derived from libpng-1.0.6, and are distributed according to the same
-disclaimer and license as libpng-1.0.6 with the following individuals
-added to the list of Contributing Authors:
+libpng versions 1.0.7, July 1, 2000, through 1.6.18, July 23, 2015, are
+Copyright (c) 2000-2002, 2004, 2006-2015 Glenn Randers-Pehrson, and are
+distributed according to the same disclaimer and license as libpng-1.0.6
+with the following individuals added to the list of Contributing Authors:

   Simon-Pierre Cadieux
   Eric S. Raymond
@@ -32,25 +31,19 @@ and with the following additions to the disclaimer:
   risk of satisfactory quality, performance, accuracy, and effort is with
   the user.

-Some files in the "contrib" directory and some configure-generated
-files that are distributed with libpng have other copyright owners and
-are released under other open source licenses.
-
 libpng versions 0.97, January 1998, through 1.0.6, March 20, 2000, are
-Copyright (c) 1998-2000 Glenn Randers-Pehrson, are derived from
-libpng-0.96, and are distributed according to the same disclaimer and
-license as libpng-0.96, with the following individuals added to the list
-of Contributing Authors:
+Copyright (c) 1998-2000 Glenn Randers-Pehrson, and are distributed according
+to the same disclaimer and license as libpng-0.96, with the following
+individuals added to the list of Contributing Authors:

   Tom Lane
   Glenn Randers-Pehrson
   Willem van Schaik

 libpng versions 0.89, June 1996, through 0.96, May 1997, are
-Copyright (c) 1996-1997 Andreas Dilger, are derived from libpng-0.88,
-and are distributed according to the same disclaimer and license as
-libpng-0.88, with the following individuals added to the list of
-Contributing Authors:
+Copyright (c) 1996-1997 Andreas Dilger, and are
+distributed according to the same disclaimer and license as libpng-0.88,
+with the following individuals added to the list of Contributing Authors:

   John Bowler
   Kevin Bracey
@@ -59,9 +52,6 @@ Contributing Authors:
   Greg Roelofs
   Tom Tanner

-Some files in the "scripts" directory have other copyright owners
-but are released under this license.
-
 libpng versions 0.5, May 1995, through 0.88, January 1996, are
 Copyright (c) 1995-1996 Guy Eric Schalnat, Group 42, Inc.

@@ -100,31 +90,18 @@ supporting the PNG file format in commercial products.  If you use this
 source code in a product, acknowledgment is not required but would be
 appreciated.

-END OF COPYRIGHT NOTICE, DISCLAIMER, and LICENSE.
+A "png_get_copyright" function is available, for convenient use in "about"
+boxes and the like:

-TRADEMARK:
+   printf("%s", png_get_copyright(NULL));

-The name "libpng" has not been registered by the Copyright owner
-as a trademark in any jurisdiction.  However, because libpng has
-been distributed and maintained world-wide, continually since 1995,
-the Copyright owner claims "common-law trademark protection" in any
-jurisdiction where common-law trademark is recognized.
-
-OSI CERTIFICATION:
+Also, the PNG logo (in PNG format, of course) is supplied in the
+files "pngbar.png" and "pngbar.jpg (88x31) and "pngnow.png" (98x31).

 Libpng is OSI Certified Open Source Software.  OSI Certified Open Source is
 a certification mark of the Open Source Initiative. OSI has not addressed
 the additional disclaimers inserted at version 1.0.7.

-EXPORT CONTROL:
-
-The Copyright owner believes that the Export Control Classification
-Number (ECCN) for libpng is EAR99, which means not subject to export
-controls or International Traffic in Arms Regulations (ITAR) because
-it is open source, publicly available software, that does not contain
-any encryption software.  See the EAR, paragraphs 734.3(b)(3) and
-734.7(b).
-
 Glenn Randers-Pehrson
 glennrp at users.sourceforge.net
-May 29, 2016
+July 23, 2015
--- a/Makefile.am
+++ b/Makefile.am
@@ -1,11 +1,6 @@
-# Makefile.am, the source file for Makefile.in (and hence Makefile), is
+# Makefile.am:
+#   Source file for Makefile.in (and hence Makefile)
 #
-# Copyright (c) 2004-2016 Glenn Randers-Pehrson
-# Last changed in libpng 1.6.22 [(PENDING RELEASE)]
-#
-# This code is released under the libpng license.
-# For conditions of distribution and use, see the disclaimer
-# and license in png.h

 PNGLIB_BASENAME= libpng@PNGLIB_MAJOR@@PNGLIB_MINOR@

@@ -13,9 +8,6 @@ ACLOCAL_AMFLAGS = -I scripts

 # test programs - run on make check, make distcheck
 check_PROGRAMS= pngtest pngunknown pngstest pngvalid pngimage
-if HAVE_CLOCK_GETTIME
-check_PROGRAMS += timepng
-endif

 # Utilities - installed
 bin_PROGRAMS= pngfix png-fix-itxt
@@ -45,9 +37,6 @@ pngunknown_LDADD = libpng@PNGLIB_MAJOR@@PNGLIB_MINOR@.la
 pngimage_SOURCES = contrib/libtests/pngimage.c
 pngimage_LDADD = libpng@PNGLIB_MAJOR@@PNGLIB_MINOR@.la

-timepng_SOURCES = contrib/libtests/timepng.c
-timepng_LDADD = libpng@PNGLIB_MAJOR@@PNGLIB_MINOR@.la
-
 pngfix_SOURCES = contrib/tools/pngfix.c
 pngfix_LDADD = libpng@PNGLIB_MAJOR@@PNGLIB_MINOR@.la

@@ -62,17 +51,23 @@ TESTS =\
   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-size\
+   tests/pngvalid-progressive-interlace-size\
   tests/pngvalid-progressive-interlace-standard\
-   tests/pngvalid-transform\
+   tests/pngvalid-progressive-interlace-transform\
   tests/pngvalid-progressive-standard tests/pngvalid-standard\
-   tests/pngstest-1.8 tests/pngstest-1.8-alpha tests/pngstest-linear\
-   tests/pngstest-linear-alpha tests/pngstest-none tests/pngstest-none-alpha\
-   tests/pngstest-sRGB tests/pngstest-sRGB-alpha tests/pngunknown-IDAT\
+   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\
   tests/pngimage-quick tests/pngimage-full

+# These tests are expected, and required, to fail:
+XFAIL_TESTS = tests/pngstest-error
+
 # man pages
 dist_man_MANS= libpng.3 libpngpf.3 png.5

--- a/2
+++ b/2
@@ -1,4 +1,4 @@
-README for libpng version 1.6.23beta01 - May 29, 2016 (shared library 16.0)
+README for libpng version 1.6.18 - July 23, 2015 (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.
--- a/arm/arm_init.c
+++ b/arm/arm_init.c
@@ -1,9 +1,9 @@

 /* arm_init.c - NEON optimised filter functions
 *
- * Copyright (c) 2014,2016 Glenn Randers-Pehrson
+ * Copyright (c) 2014 Glenn Randers-Pehrson
 * Written by Mans Rullgard, 2011.
- * Last changed in libpng 1.6.22 [(PENDING RELEASE)]
+ * Last changed in libpng 1.6.16 [December 22, 2014]
 *
 * This code is released under the libpng license.
 * For conditions of distribution and use, see the disclaimer
@@ -66,7 +66,6 @@ png_init_filter_functions_neon(png_structp pp, unsigned int bpp)
    * wrong order of the 'ON' and 'default' cases.  UNSET now defaults to OFF,
    * as documented in png.h
    */
-   png_debug(1, "in png_init_filter_functions_neon");
 #ifdef PNG_ARM_NEON_API_SUPPORTED
   switch ((pp->options >> PNG_ARM_NEON) & 3)
   {
--- a/arm/filter_neon_intrinsics.c
+++ b/arm/filter_neon_intrinsics.c
@@ -1,11 +1,11 @@

 /* filter_neon_intrinsics.c - NEON optimised filter functions
 *
- * Copyright (c) 2014,2016 Glenn Randers-Pehrson
+ * Copyright (c) 2014 Glenn Randers-Pehrson
 * Written by James Yu <james.yu at linaro.org>, October 2013.
 * Based on filter_neon.S, written by Mans Rullgard, 2011.
 *
- * Last changed in libpng 1.6.22 [(PENDING RELEASE)]
+ * Last changed in libpng 1.6.16 [December 22, 2014]
 *
 * This code is released under the libpng license.
 * For conditions of distribution and use, see the disclaimer
@@ -47,8 +47,6 @@ png_read_filter_row_up_neon(png_row_infop row_info, png_bytep row,
   png_bytep rp_stop = row + row_info->rowbytes;
   png_const_bytep pp = prev_row;

-   png_debug(1, "in png_read_filter_row_up_neon");
-
   for (; rp < rp_stop; rp += 16, pp += 16)
   {
      uint8x16_t qrp, qpp;
@@ -74,8 +72,6 @@ png_read_filter_row_sub3_neon(png_row_infop row_info, png_bytep row,
   uint8x8x4_t vdest;
   vdest.val[3] = vdup_n_u8(0);

-   png_debug(1, "in png_read_filter_row_sub3_neon");
-
   for (; rp < rp_stop;)
   {
      uint8x8_t vtmp1, vtmp2;
@@ -117,8 +113,6 @@ png_read_filter_row_sub4_neon(png_row_infop row_info, png_bytep row,
   uint8x8x4_t vdest;
   vdest.val[3] = vdup_n_u8(0);

-   png_debug(1, "in png_read_filter_row_sub4_neon");
-
   for (; rp < rp_stop; rp += 16)
   {
      uint32x2x4_t vtmp = vld4_u32(png_ptr(uint32_t,rp));
@@ -154,8 +148,6 @@ png_read_filter_row_avg3_neon(png_row_infop row_info, png_bytep row,
   vrpt = png_ptr(uint8x8x2_t,&vtmp);
   vrp = *vrpt;

-   png_debug(1, "in png_read_filter_row_avg3_neon");
-
   for (; rp < rp_stop; pp += 12)
   {
      uint8x8_t vtmp1, vtmp2, vtmp3;
@@ -215,8 +207,6 @@ png_read_filter_row_avg4_neon(png_row_infop row_info, png_bytep row,
   uint8x8x4_t vdest;
   vdest.val[3] = vdup_n_u8(0);

-   png_debug(1, "in png_read_filter_row_avg4_neon");
-
   for (; rp < rp_stop; rp += 16, pp += 16)
   {
      uint32x2x4_t vtmp;
@@ -290,8 +280,6 @@ png_read_filter_row_paeth3_neon(png_row_infop row_info, png_bytep row,
   vrpt = png_ptr(uint8x8x2_t,&vtmp);
   vrp = *vrpt;

-   png_debug(1, "in png_read_filter_row_paeth3_neon");
-
   for (; rp < rp_stop; pp += 12)
   {
      uint8x8x2_t *vppt;
@@ -351,8 +339,6 @@ png_read_filter_row_paeth4_neon(png_row_infop row_info, png_bytep row,
   uint8x8x4_t vdest;
   vdest.val[3] = vdup_n_u8(0);

-   png_debug(1, "in png_read_filter_row_paeth4_neon");
-
   for (; rp < rp_stop; rp += 16, pp += 16)
   {
      uint32x2x4_t vtmp;
--- a/autogen.sh
+++ b/autogen.sh
@@ -74,12 +74,12 @@ 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.h.in~ config.sub configure depcomp install-sh ltmain.sh missing\
   test-driver"
 #
 # Files generated by versions of configue >2.68 or automake >1.13 (i.e. later
 # versions than those required by configure.ac):
-libpng_autotools_extra="compile config.h.in~"
+libpng_autotools_extra="compile"
 #
 # These are separate because 'maintainer-clean' does not remove them.
 libpng_libtool_files="scripts/libtool.m4 scripts/ltoptions.m4\
--- a/configure.ac
+++ b/configure.ac
@@ -1,12 +1,5 @@
 # configure.ac

-# Copyright (c) 2004-2015 Glenn Randers-Pehrson
-# Last changed in libpng 1.6.22 [(PENDING RELEASE)]
-
-# This code is released under the libpng license.
-# For conditions of distribution and use, see the disclaimer
-# and license in png.h
-
 dnl Process this file with autoconf to produce a configure script.
 dnl
 dnl Minor upgrades (compatible ABI): increment the package version
@@ -25,7 +18,7 @@ AC_PREREQ([2.68])

 dnl Version number stuff here:

-AC_INIT([libpng],[1.6.23beta01],[png-mng-implement@lists.sourceforge.net])
+AC_INIT([libpng],[1.6.18],[png-mng-implement@lists.sourceforge.net])
 AC_CONFIG_MACRO_DIR([scripts])

 # libpng does not follow GNU file name conventions (hence 'foreign')
@@ -46,10 +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=1.6.23beta01
+PNGLIB_VERSION=1.6.18
 PNGLIB_MAJOR=1
 PNGLIB_MINOR=6
-PNGLIB_RELEASE=23
+PNGLIB_RELEASE=18

 dnl End of version number stuff

@@ -114,25 +107,6 @@ AC_ARG_ENABLE(werror,
      CFLAGS="$sav_CFLAGS"
    fi],)

-# For GCC 5 the default mode for C is -std=gnu11 instead of -std=gnu89
-# In pngpriv.h we request just the POSIX 1003.1 and C89 APIs by defining _POSIX_SOURCE to 1
-# This is incompatible with the new default mode, so we test for that and force the 
-# "-std=c89" compiler option:
-AC_MSG_CHECKING([if we need to force back C standard to C89])
-AC_COMPILE_IFELSE(
-   [AC_LANG_PROGRAM([
-      [#define _POSIX_SOURCE 1]
-      [#include <stdio.h>]
-   ])],
-   AC_MSG_RESULT(no),[
-      if test "x$GCC" != "xyes"; then
-         AC_MSG_ERROR(
-            [Forcing back to C89 is required but the flags are only known for GCC])
-      fi
-   AC_MSG_RESULT(yes)
-   CFLAGS="$CFLAGS -std=c89"
-])
-
 # Checks for header files.
 AC_HEADER_STDC

@@ -146,12 +120,6 @@ AC_C_RESTRICT
 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)) )
-
-# Some later POSIX 1003.1 functions are required for test programs, failure here
-# is soft (the corresponding test program is not built).
-AC_CHECK_FUNC([clock_gettime],,[AC_MSG_WARN([not building timepng])])
-AM_CONDITIONAL([HAVE_CLOCK_GETTIME], [test "$ac_cv_func_clock_gettime" = "yes"])
-
 AC_ARG_WITH(zlib-prefix,
   AS_HELP_STRING([[[--with-zlib-prefix]]],
      [prefix that may have been used in installed zlib]),
--- a/contrib/README.txt
+++ b/contrib/README.txt
@@ -1,5 +1,4 @@

 This "contrib" directory contains contributions which are not necessarily under
 the libpng license, although all are open source.  They are not part of
-libpng proper and are not used for building the library, although some are used
-for testing the library via "make check".
+libpng proper and are not used for building the library.
--- a/contrib/arm-neon/linux-auxv.c
+++ b/contrib/arm-neon/linux-auxv.c
@@ -7,7 +7,7 @@
 * This code is released under the libpng license.
 * For conditions of distribution and use, see the disclaimer
 * and license in png.h
- *
+ * 
 * SEE contrib/arm-neon/README before reporting bugs
 *
 * STATUS: COMPILED, TESTED
--- a/contrib/arm-neon/linux.c
+++ b/contrib/arm-neon/linux.c
@@ -72,7 +72,7 @@ png_have_neon(png_structp png_ptr)
                     state = Colon;
                  break;
               }
-
+               
               /* did not match 'feature' */
               state = SkipLine;
               /* FALL THROUGH */
--- a/contrib/examples/pngpixel.c
+++ b/contrib/examples/pngpixel.c
@@ -87,7 +87,7 @@ print_pixel(png_structp png_ptr, png_infop info_ptr, png_const_bytep row,
       */
      case PNG_COLOR_TYPE_PALETTE:
         {
-            PNG_CONST int index = component(row, x, 0, bit_depth, 1);
+            PNG_CONST unsigned int index = component(row, x, 0, bit_depth, 1);
            png_colorp palette = NULL;
            int num_palette = 0;

--- a/contrib/examples/simpleover.c
+++ b/contrib/examples/simpleover.c
@@ -136,7 +136,7 @@ sprite_op(const struct sprite *sprite, int x_offset, int y_offset,
            /* This is the optimized Porter-Duff 'Over' operation, when the
             * input alpha is 0 the output is not changed.
             */
-            if (in_alpha > 0)
+            if (in_alpha > 0) 
            {
               png_uint_16 *out_pixel = sprite->buffer +
                  ((y+y_offset) * sprite->width + (x+x_offset))*4;
@@ -184,7 +184,7 @@ sprite_op(const struct sprite *sprite, int x_offset, int y_offset,
   }
 }

-static int
+static int 
 create_sprite(struct sprite *sprite, int *argc, const char ***argv)
 {
   /* Read the arguments and create this sprite. The sprite buffer has already
@@ -415,7 +415,7 @@ simpleover_process(png_imagep output, png_bytep out_buf, int argc,
            n = sscanf(argv[0], "--sprite=%u,%u,%" str(sprite_name_chars) "s%c",
                &sprites[nsprites].width, &sprites[nsprites].height,
                sprites[nsprites].name, &tombstone);
-
+            
            if ((n == 2 || n == 3) &&
                sprites[nsprites].width > 0 && sprites[nsprites].height > 0)
            {
@@ -492,7 +492,7 @@ simpleover_process(png_imagep output, png_bytep out_buf, int argc,
               if (!add_sprite(output, out_buf, sprites+isprite, &argc, &argv))
                  goto out; /* error in add_sprite */

-               break;
+               break; 
            }
         }

--- a/contrib/gregbook/readpng2.c
+++ b/contrib/gregbook/readpng2.c
@@ -4,7 +4,7 @@

  ---------------------------------------------------------------------------

-      Copyright (c) 1998-2015 Greg Roelofs.  All rights reserved.
+      Copyright (c) 1998-2007 Greg Roelofs.  All rights reserved.

      This software is provided "as is," without warranty of any kind,
      express or implied.  In no event shall the author or contributors
@@ -51,11 +51,6 @@
      along with this program; if not, write to the Free Software Foundation,
      Inc., 59 Temple Place, Suite 330, Boston, MA  02111-1307  USA

-  ---------------------------------------------------------------------------
-
-   Changelog:
-     2015-11-12 - Check return value of png_get_bKGD() (Glenn R-P)
-
  ---------------------------------------------------------------------------*/


@@ -266,38 +261,36 @@ static void readpng2_info_callback(png_structp png_ptr, png_infop info_ptr)
    /* since we know we've read all of the PNG file's "header" (i.e., up
     * to IDAT), we can check for a background color here */

-    if (mainprog_ptr->need_bgcolor)
+    if (mainprog_ptr->need_bgcolor &&
+        png_get_valid(png_ptr, info_ptr, PNG_INFO_bKGD))
    {
        png_color_16p pBackground;

        /* it is not obvious from the libpng documentation, but this function
         * takes a pointer to a pointer, and it always returns valid red,
         * green and blue values, regardless of color_type: */
-        if (png_get_bKGD(png_ptr, info_ptr, &pBackground))
-        {
+        png_get_bKGD(png_ptr, info_ptr, &pBackground);

-           /* however, it always returns the raw bKGD data, regardless of any
-            * bit-depth transformations, so check depth and adjust if necessary
-            */
-           if (bit_depth == 16) {
-               mainprog_ptr->bg_red   = pBackground->red   >> 8;
-               mainprog_ptr->bg_green = pBackground->green >> 8;
-               mainprog_ptr->bg_blue  = pBackground->blue  >> 8;
-           } else if (color_type == PNG_COLOR_TYPE_GRAY && bit_depth < 8) {
-               if (bit_depth == 1)
-                   mainprog_ptr->bg_red = mainprog_ptr->bg_green =
-                     mainprog_ptr->bg_blue = pBackground->gray? 255 : 0;
-               else if (bit_depth == 2)
-                   mainprog_ptr->bg_red = mainprog_ptr->bg_green =
-                     mainprog_ptr->bg_blue = (255/3) * pBackground->gray;
-               else /* bit_depth == 4 */
-                   mainprog_ptr->bg_red = mainprog_ptr->bg_green =
-                     mainprog_ptr->bg_blue = (255/15) * pBackground->gray;
-           } else {
-               mainprog_ptr->bg_red   = (uch)pBackground->red;
-               mainprog_ptr->bg_green = (uch)pBackground->green;
-               mainprog_ptr->bg_blue  = (uch)pBackground->blue;
-           }
+        /* however, it always returns the raw bKGD data, regardless of any
+         * bit-depth transformations, so check depth and adjust if necessary */
+        if (bit_depth == 16) {
+            mainprog_ptr->bg_red   = pBackground->red   >> 8;
+            mainprog_ptr->bg_green = pBackground->green >> 8;
+            mainprog_ptr->bg_blue  = pBackground->blue  >> 8;
+        } else if (color_type == PNG_COLOR_TYPE_GRAY && bit_depth < 8) {
+            if (bit_depth == 1)
+                mainprog_ptr->bg_red = mainprog_ptr->bg_green =
+                  mainprog_ptr->bg_blue = pBackground->gray? 255 : 0;
+            else if (bit_depth == 2)
+                mainprog_ptr->bg_red = mainprog_ptr->bg_green =
+                  mainprog_ptr->bg_blue = (255/3) * pBackground->gray;
+            else /* bit_depth == 4 */
+                mainprog_ptr->bg_red = mainprog_ptr->bg_green =
+                  mainprog_ptr->bg_blue = (255/15) * pBackground->gray;
+        } else {
+            mainprog_ptr->bg_red   = (uch)pBackground->red;
+            mainprog_ptr->bg_green = (uch)pBackground->green;
+            mainprog_ptr->bg_blue  = (uch)pBackground->blue;
        }
    }

--- a/contrib/gregbook/rpng2-win.c
+++ b/contrib/gregbook/rpng2-win.c
@@ -33,7 +33,7 @@
    - 2.02:  fixed improper display of usage screen on PNG error(s); fixed
              unexpected-EOF and file-read-error cases
    - 2.03:  removed runtime MMX-enabling/disabling and obsolete -mmx* options
-    - 2.04:
+    - 2.04:  
             (GR-P)

  ---------------------------------------------------------------------------
--- a/contrib/gregbook/rpng2-x.c
+++ b/contrib/gregbook/rpng2-x.c
@@ -43,10 +43,12 @@
    - 2.03:  deleted runtime MMX-enabling/disabling and obsolete -mmx* options
    - 2.04:  Added "void(foo);" statements to quiet pedantic compiler warnings
             about unused variables (GR-P)
-    - 2.05:  Use nanosleep() instead of usleep(), which is deprecated (GR-P).
+
+  TO DO:
+             use nanosleep() instead of usleep(), which is obsolete/deprecated.
  ---------------------------------------------------------------------------

-      Copyright (c) 1998-2010, 2014-2015 Greg Roelofs.  All rights reserved.
+      Copyright (c) 1998-2008 Greg Roelofs.  All rights reserved.

      This software is provided "as is," without warranty of any kind,
      express or implied.  In no event shall the author or contributors
@@ -117,7 +119,6 @@
 # undef usleep
 # define usleep(usec) {        \
   struct timespec ts;         \
-   ts.tv_sec = 0;              \
   ts.tv_nsec = (usec) * 1000; \
   nanosleep(&ts, NULL); }
 #  endif
@@ -496,12 +497,12 @@ int main(int argc, char **argv)
          "\t\t  transparent images; overrides -bgcolor\n",
          num_bgpat-1);
 #ifdef FEATURE_LOOP
-        fprintf(stderr,
+        fprintf(stderr, 
          "    -loop\tloops through background images after initial display\n"
          "\t\t  is complete (depends on -bgpat)\n"
          "    sec \tseconds to display each background image (default = 2)\n");
 #endif
-        fprintf(stderr,
+        fprintf(stderr, 
          "    dur \tduration in microseconds to wait after displaying each\n"
          "\t\t  row (for demo purposes)\n"
          "    -timing\tenables delay for every block read, to simulate modem\n"
--- a/contrib/intel/INSTALL
+++ b/contrib/intel/INSTALL
@@ -1,158 +0,0 @@
-Enabling SSE support
-
-Copyright (c) 2016 Google, Inc.
-Written by Mike Klein, Matt Sarett
-
-This INSTALL file written by Glenn Randers-Pehrson, 2016.
-
-If you have moved intel_init.c and filter_sse2_intrinsics.c to a different
-directory, be sure to update the '#include "../../pngpriv.h"' line in both
-files if necessary to point to the correct relative location of pngpriv.h
-with respect to the new location of those files.
-
-To enable SSE support in libpng, follow the instructions in I, II, or III,
-below:
-
-I. Using patched "configure" scripts:
-
-First, apply intel_sse.patch in your build directory.
-
-   patch -i contrib/intel/intel_sse.patch -p1
-
-Then, if you are not building in a new GIT clone, e.g., in a tar
-distribution, remove any existing pre-built configure scripts:
-
-   ./configure --enable-maintainer-mode
-   make maintainer-clean
-   ./autogen.sh --maintainer --clean
-
-Finally, configure libpng with -DPNG_INTEL_SSE in CPPFLAGS:
-
-   ./autogen.sh --maintainer
-   CPPFLAGS="-DPNG_INTEL_SSE" ./configure [options]
-   make CPPFLAGS="-DPNG_INTEL_SSE" [options]
-   make
-
-II. Using a custom makefile:
-
-If you are using a custom makefile makefile, you will have to update it
-manually to include contrib/intel/*.o in the dependencies, and to define
-PNG_INTEL_SSE.
-
-III. Using manually updated "configure" scripts:
-
-If you prefer, manually edit pngpriv.h, configure.ac, and Makefile.am,
-following the instructions below, then follow the instructions in
-section II of INSTALL in the main libpng directory, then configure libpng
-with -DPNG_INTEL_SSE in CPPFLAGS.
-
-1. Add the following code to configure.ac under HOST SPECIFIC OPTIONS
-directly beneath the section for ARM:
-
-----------------cut----------------
-# INTEL
-# =====
-#
-# INTEL SSE (SIMD) support.
-
-AC_ARG_ENABLE([intel-sse],
-   AS_HELP_STRING([[[--enable-intel-sse]]],
-      [Enable Intel SSE optimizations: =no/off, yes/on:]
-      [no/off: disable the optimizations;]
-      [yes/on: enable the optimizations.]
-      [If not specified: determined by the compiler.]),
-   [case "$enableval" in
-      no|off)
-         # disable the default enabling:
-         AC_DEFINE([PNG_INTEL_SSE_OPT], [0],
-                   [Disable Intel SSE optimizations])
-         # Prevent inclusion of the assembler files below:
-         enable_intel_sse=no;;
-      yes|on)
-         AC_DEFINE([PNG_INTEL_SSE_OPT], [1],
-                   [Enable Intel SSE optimizations]);;
-      *)
-         AC_MSG_ERROR([--enable-intel-sse=${enable_intel_sse}: invalid value])
-   esac])
-
-# Add Intel specific files to all builds where the host_cpu is Intel ('x86*')
-# or where Intel optimizations were explicitly requested (this allows a
-# fallback if a future host CPU does not match 'x86*')
-AM_CONDITIONAL([PNG_INTEL_SSE],
-   [test "$enable_intel_sse" != 'no' &&
-    case "$host_cpu" in
-      i?86|x86_64) :;;
-      *)    test "$enable_intel_sse" != '';;
-    esac])
-----------------cut----------------
-
-2. Add the following code to Makefile.am under HOST SPECIFIC OPTIONS
-directly beneath the "if PNG_ARM_NEON ... endif" statement:
-
-----------------cut----------------
-if PNG_INTEL_SSE
-libpng@PNGLIB_MAJOR@@PNGLIB_MINOR@_la_SOURCES += contrib/intel/intel_init.c\
-    contrib/intel/filter_sse2_intrinsics.c
-endif
-----------------cut----------------
-
-3. Add the following lines to pngpriv.h, following the PNG_ARM_NEON_OPT
-code:
-
-----------------cut----------------
-#ifndef PNG_INTEL_SSE_OPT
-#   ifdef PNG_INTEL_SSE
-      /* Only check for SSE if the build configuration has been modified to
-       * enable SSE optimizations.  This means that these optimizations will
-       * be off by default.  See contrib/intel for more details.
-       */
-#     if defined(__SSE4_1__) || defined(__AVX__) || defined(__SSSE3__) || \
-       defined(__SSE2__) || defined(_M_X64) || defined(_M_AMD64) || \
-       (defined(_M_IX86_FP) && _M_IX86_FP >= 2)
-#         define PNG_INTEL_SSE_OPT 1
-#      endif
-#   endif
-#endif
-
-#if PNG_INTEL_SSE_OPT > 0
-#   ifndef PNG_INTEL_SSE_IMPLEMENTATION
-#      if defined(__SSE4_1__) || defined(__AVX__)
-          /* We are not actually using AVX, but checking for AVX is the best
-             way we can detect SSE4.1 and SSSE3 on MSVC.
-          */
-#         define PNG_INTEL_SSE_IMPLEMENTATION 3
-#      elif defined(__SSSE3__)
-#         define PNG_INTEL_SSE_IMPLEMENTATION 2
-#      elif defined(__SSE2__) || defined(_M_X64) || defined(_M_AMD64) || \
-       (defined(_M_IX86_FP) && _M_IX86_FP >= 2)
-#         define PNG_INTEL_SSE_IMPLEMENTATION 1
-#      else
-#         define PNG_INTEL_SSE_IMPLEMENTATION 0
-#      endif
-#   endif
-
-#   if PNG_INTEL_SSE_IMPLEMENTATION > 0
-#      define PNG_FILTER_OPTIMIZATIONS png_init_filter_functions_sse2
-#   endif
-#endif
-
-----------------cut----------------
-
-4. Add the following lines to pngpriv.h, following the prototype for
-png_read_filter_row_paeth4_neon:
-
-----------------cut----------------
-PNG_INTERNAL_FUNCTION(void,png_read_filter_row_sub3_sse2,(png_row_infop
-    row_info, png_bytep row, png_const_bytep prev_row),PNG_EMPTY);
-PNG_INTERNAL_FUNCTION(void,png_read_filter_row_sub4_sse2,(png_row_infop
-    row_info, png_bytep row, png_const_bytep prev_row),PNG_EMPTY);
-PNG_INTERNAL_FUNCTION(void,png_read_filter_row_avg3_sse2,(png_row_infop
-    row_info, png_bytep row, png_const_bytep prev_row),PNG_EMPTY);
-PNG_INTERNAL_FUNCTION(void,png_read_filter_row_avg4_sse2,(png_row_infop
-    row_info, png_bytep row, png_const_bytep prev_row),PNG_EMPTY);
-PNG_INTERNAL_FUNCTION(void,png_read_filter_row_paeth3_sse2,(png_row_infop
-    row_info, png_bytep row, png_const_bytep prev_row),PNG_EMPTY);
-PNG_INTERNAL_FUNCTION(void,png_read_filter_row_paeth4_sse2,(png_row_infop
-    row_info, png_bytep row, png_const_bytep prev_row),PNG_EMPTY);
-
-----------------cut----------------
--- a/contrib/intel/filter_sse2_intrinsics.c
+++ b/contrib/intel/filter_sse2_intrinsics.c
@@ -1,379 +0,0 @@
-
-/* filter_sse2_intrinsics.c - SSE2 optimized filter functions
- *
- * Copyright (c) 2016 Google, Inc.
- * Written by Mike Klein and Matt Sarett
- * Derived from arm/filter_neon_intrinsics.c, which was
- * Copyright (c) 2014,2016 Glenn Randers-Pehrson
- *
- * Last changed in libpng 1.6.22 [May 26, 2016]
- *
- * This code is released under the libpng license.
- * For conditions of distribution and use, see the disclaimer
- * and license in png.h
- */
-
-#include "../../pngpriv.h"
-
-#ifdef PNG_READ_SUPPORTED
-
-#if PNG_INTEL_SSE_IMPLEMENTATION > 0
-
-#include <immintrin.h>
-
-/* Functions in this file look at most 3 pixels (a,b,c) to predict the 4th (d).
- * They're positioned like this:
- *    prev:  c b
- *    row:   a d
- * The Sub filter predicts d=a, Avg d=(a+b)/2, and Paeth predicts d to be
- * whichever of a, b, or c is closest to p=a+b-c.
- */
-
-static __m128i load4(const void* p) {
-   return _mm_cvtsi32_si128(*(const int*)p);
-}
-
-static void store4(void* p, __m128i v) {
-   *(int*)p = _mm_cvtsi128_si32(v);
-}
-
-static __m128i load3(const void* p) {
-   /* We'll load 2 bytes, then 1 byte,
-    * then mask them together, and finally load into SSE.
-    */
-   const png_uint_16* p01 = p;
-   const png_byte*    p2  = (const png_byte*)(p01+1);
-
-   png_uint_32 v012 = (png_uint_32)(*p01)
-                    | (png_uint_32)(*p2) << 16;
-   return load4(&v012);
-}
-
-static void store3(void* p, __m128i v) {
-   /* We'll pull from SSE as a 32-bit int, then write
-    * its bottom two bytes, then its third byte.
-    */
-   png_uint_32 v012;
-   store4(&v012, v);
-
-   png_uint_16* p01 = p;
-   png_byte*    p2  = (png_byte*)(p01+1);
-   *p01 = v012;
-   *p2  = v012 >> 16;
-}
-
-void png_read_filter_row_sub3_sse2(png_row_infop row_info, png_bytep row,
-   png_const_bytep prev)
-{
-   /* The Sub filter predicts each pixel as the previous pixel, a.
-    * There is no pixel to the left of the first pixel.  It's encoded directly.
-    * That works with our main loop if we just say that left pixel was zero.
-    */
-   png_debug(1, "in png_read_filter_row_sub3_sse2");
-   __m128i a, d = _mm_setzero_si128();
-
-   int rb = row_info->rowbytes;
-   while (rb >= 4) {
-      a = d; d = load4(row);
-      d = _mm_add_epi8(d, a);
-      store3(row, d);
-
-      row += 3;
-      rb  -= 3;
-   }
-   if (rb > 0) {
-      a = d; d = load3(row);
-      d = _mm_add_epi8(d, a);
-      store3(row, d);
-
-      row += 3;
-      rb  -= 3;
-   }
-}
-
-void png_read_filter_row_sub4_sse2(png_row_infop row_info, png_bytep row,
-   png_const_bytep prev)
-{
-   /* The Sub filter predicts each pixel as the previous pixel, a.
-    * There is no pixel to the left of the first pixel.  It's encoded directly.
-    * That works with our main loop if we just say that left pixel was zero.
-    */
-   png_debug(1, "in png_read_filter_row_sub4_sse2");
-   __m128i a, d = _mm_setzero_si128();
-
-   int rb = row_info->rowbytes;
-   while (rb > 0) {
-      a = d; d = load4(row);
-      d = _mm_add_epi8(d, a);
-      store4(row, d);
-
-      row += 4;
-      rb  -= 4;
-   }
-}
-
-void png_read_filter_row_avg3_sse2(png_row_infop row_info, png_bytep row,
-   png_const_bytep prev)
-{
-   /* The Avg filter predicts each pixel as the (truncated) average of a and b.
-    * There's no pixel to the left of the first pixel.  Luckily, it's
-    * predicted to be half of the pixel above it.  So again, this works
-    * perfectly with our loop if we make sure a starts at zero.
-    */
-   png_debug(1, "in png_read_filter_row_avg3_sse2");
-   const __m128i zero = _mm_setzero_si128();
-   __m128i    b;
-   __m128i a, d = zero;
-
-   int rb = row_info->rowbytes;
-   while (rb >= 4) {
-             b = load4(prev);
-      a = d; d = load4(row );
-
-      /* PNG requires a truncating average, so we can't just use _mm_avg_epu8 */
-      __m128i avg = _mm_avg_epu8(a,b);
-      /* ...but we can fix it up by subtracting off 1 if it rounded up. */
-      avg = _mm_sub_epi8(avg, _mm_and_si128(_mm_xor_si128(a,b),
-                                            _mm_set1_epi8(1)));
-      d = _mm_add_epi8(d, avg);
-      store3(row, d);
-
-      prev += 3;
-      row  += 3;
-      rb   -= 3;
-   }
-   if (rb > 0) {
-             b = load3(prev);
-      a = d; d = load3(row );
-
-      /* PNG requires a truncating average, so we can't just use _mm_avg_epu8 */
-      __m128i avg = _mm_avg_epu8(a,b);
-      /* ...but we can fix it up by subtracting off 1 if it rounded up. */
-      avg = _mm_sub_epi8(avg, _mm_and_si128(_mm_xor_si128(a,b),
-                                            _mm_set1_epi8(1)));
-
-      d = _mm_add_epi8(d, avg);
-      store3(row, d);
-
-      prev += 3;
-      row  += 3;
-      rb   -= 3;
-   }
-}
-
-void png_read_filter_row_avg4_sse2(png_row_infop row_info, png_bytep row,
-   png_const_bytep prev)
-{
-   /* The Avg filter predicts each pixel as the (truncated) average of a and b.
-    * There's no pixel to the left of the first pixel.  Luckily, it's
-    * predicted to be half of the pixel above it.  So again, this works
-    * perfectly with our loop if we make sure a starts at zero.
-    */
-   png_debug(1, "in png_read_filter_row_avg4_sse2");
-   const __m128i zero = _mm_setzero_si128();
-   __m128i    b;
-   __m128i a, d = zero;
-
-   int rb = row_info->rowbytes;
-   while (rb > 0) {
-             b = load4(prev);
-      a = d; d = load4(row );
-
-      /* PNG requires a truncating average, so we can't just use _mm_avg_epu8 */
-      __m128i avg = _mm_avg_epu8(a,b);
-      /* ...but we can fix it up by subtracting off 1 if it rounded up. */
-      avg = _mm_sub_epi8(avg, _mm_and_si128(_mm_xor_si128(a,b),
-                                            _mm_set1_epi8(1)));
-
-      d = _mm_add_epi8(d, avg);
-      store4(row, d);
-
-      prev += 4;
-      row  += 4;
-      rb   -= 4;
-   }
-}
-
-/* Returns |x| for 16-bit lanes. */
-static __m128i abs_i16(__m128i x) {
-#if PNG_INTEL_SSE_IMPLEMENTATION >= 2
-   return _mm_abs_epi16(x);
-#else
-   /* Read this all as, return x<0 ? -x : x.
-   * To negate two's complement, you flip all the bits then add 1.
-    */
-   __m128i is_negative = _mm_cmplt_epi16(x, _mm_setzero_si128());
-
-   /* Flip negative lanes. */
-   x = _mm_xor_si128(x, is_negative);
-
-   /* +1 to negative lanes, else +0. */
-   x = _mm_add_epi16(x, _mm_srli_epi16(is_negative, 15));
-   return x;
-#endif
-}
-
-/* Bytewise c ? t : e. */
-static __m128i if_then_else(__m128i c, __m128i t, __m128i e) {
-#if PNG_INTEL_SSE_IMPLEMENTATION >= 3
-   return _mm_blendv_epi8(e,t,c);
-#else
-   return _mm_or_si128(_mm_and_si128(c, t), _mm_andnot_si128(c, e));
-#endif
-}
-
-void png_read_filter_row_paeth3_sse2(png_row_infop row_info, png_bytep row,
-   png_const_bytep prev)
-{
-   /* Paeth tries to predict pixel d using the pixel to the left of it, a,
-    * and two pixels from the previous row, b and c:
-    *   prev: c b
-    *   row:  a d
-    * The Paeth function predicts d to be whichever of a, b, or c is nearest to
-    * p=a+b-c.
-    *
-    * The first pixel has no left context, and so uses an Up filter, p = b.
-    * This works naturally with our main loop's p = a+b-c if we force a and c
-    * to zero.
-    * Here we zero b and d, which become c and a respectively at the start of
-    * the loop.
-    */
-   png_debug(1, "in png_read_filter_row_paeth3_sse2");
-   const __m128i zero = _mm_setzero_si128();
-   __m128i c, b = zero,
-           a, d = zero;
-
-   int rb = row_info->rowbytes;
-   while (rb >= 4) {
-      /* It's easiest to do this math (particularly, deal with pc) with 16-bit
-       * intermediates.
-       */
-      c = b; b = _mm_unpacklo_epi8(load4(prev), zero);
-      a = d; d = _mm_unpacklo_epi8(load4(row ), zero);
-
-      /* (p-a) == (a+b-c - a) == (b-c) */
-      __m128i pa = _mm_sub_epi16(b,c);
-
-      /* (p-b) == (a+b-c - b) == (a-c) */
-      __m128i pb = _mm_sub_epi16(a,c);
-
-      /* (p-c) == (a+b-c - c) == (a+b-c-c) == (b-c)+(a-c) */
-      __m128i pc = _mm_add_epi16(pa,pb);
-
-      pa = abs_i16(pa);  /* |p-a| */
-      pb = abs_i16(pb);  /* |p-b| */
-      pc = abs_i16(pc);  /* |p-c| */
-
-      __m128i smallest = _mm_min_epi16(pc, _mm_min_epi16(pa, pb));
-
-      /* Paeth breaks ties favoring a over b over c. */
-      __m128i nearest  = if_then_else(_mm_cmpeq_epi16(smallest, pa), a,
-                         if_then_else(_mm_cmpeq_epi16(smallest, pb), b,
-                                                                     c));
-
-      /* Note `_epi8`: we need addition to wrap modulo 255. */
-      d = _mm_add_epi8(d, nearest);
-      store3(row, _mm_packus_epi16(d,d));
-
-      prev += 3;
-      row  += 3;
-      rb   -= 3;
-   }
-   if (rb > 0) {
-      /* It's easiest to do this math (particularly, deal with pc) with 16-bit
-       * intermediates.
-       */
-      c = b; b = _mm_unpacklo_epi8(load3(prev), zero);
-      a = d; d = _mm_unpacklo_epi8(load3(row ), zero);
-
-      /* (p-a) == (a+b-c - a) == (b-c) */
-      __m128i pa = _mm_sub_epi16(b,c);
-
-      /* (p-b) == (a+b-c - b) == (a-c) */
-      __m128i pb = _mm_sub_epi16(a,c);
-
-      /* (p-c) == (a+b-c - c) == (a+b-c-c) == (b-c)+(a-c) */
-      __m128i pc = _mm_add_epi16(pa,pb);
-
-      pa = abs_i16(pa);  /* |p-a| */
-      pb = abs_i16(pb);  /* |p-b| */
-      pc = abs_i16(pc);  /* |p-c| */
-
-      __m128i smallest = _mm_min_epi16(pc, _mm_min_epi16(pa, pb));
-
-      /* Paeth breaks ties favoring a over b over c. */
-      __m128i nearest  = if_then_else(_mm_cmpeq_epi16(smallest, pa), a,
-                         if_then_else(_mm_cmpeq_epi16(smallest, pb), b,
-                                                                     c));
-
-      /* Note `_epi8`: we need addition to wrap modulo 255. */
-      d = _mm_add_epi8(d, nearest);
-      store3(row, _mm_packus_epi16(d,d));
-
-      prev += 3;
-      row  += 3;
-      rb   -= 3;
-   }
-}
-
-void png_read_filter_row_paeth4_sse2(png_row_infop row_info, png_bytep row,
-   png_const_bytep prev)
-{
-   /* Paeth tries to predict pixel d using the pixel to the left of it, a,
-    * and two pixels from the previous row, b and c:
-    *   prev: c b
-    *   row:  a d
-    * The Paeth function predicts d to be whichever of a, b, or c is nearest to
-    * p=a+b-c.
-    *
-    * The first pixel has no left context, and so uses an Up filter, p = b.
-    * This works naturally with our main loop's p = a+b-c if we force a and c
-    * to zero.
-    * Here we zero b and d, which become c and a respectively at the start of
-    * the loop.
-    */
-   png_debug(1, "in png_read_filter_row_paeth4_sse2");
-   const __m128i zero = _mm_setzero_si128();
-   __m128i c, b = zero,
-           a, d = zero;
-
-   int rb = row_info->rowbytes;
-   while (rb > 0) {
-      /* It's easiest to do this math (particularly, deal with pc) with 16-bit
-       * intermediates.
-       */
-      c = b; b = _mm_unpacklo_epi8(load4(prev), zero);
-      a = d; d = _mm_unpacklo_epi8(load4(row ), zero);
-
-      /* (p-a) == (a+b-c - a) == (b-c) */
-      __m128i pa = _mm_sub_epi16(b,c);
-
-      /* (p-b) == (a+b-c - b) == (a-c) */
-      __m128i pb = _mm_sub_epi16(a,c);
-
-      /* (p-c) == (a+b-c - c) == (a+b-c-c) == (b-c)+(a-c) */
-      __m128i pc = _mm_add_epi16(pa,pb);
-
-      pa = abs_i16(pa);  /* |p-a| */
-      pb = abs_i16(pb);  /* |p-b| */
-      pc = abs_i16(pc);  /* |p-c| */
-
-      __m128i smallest = _mm_min_epi16(pc, _mm_min_epi16(pa, pb));
-
-      /* Paeth breaks ties favoring a over b over c. */
-      __m128i nearest  = if_then_else(_mm_cmpeq_epi16(smallest, pa), a,
-                         if_then_else(_mm_cmpeq_epi16(smallest, pb), b,
-                                                                     c));
-
-      /* Note `_epi8`: we need addition to wrap modulo 255. */
-      d = _mm_add_epi8(d, nearest);
-      store4(row, _mm_packus_epi16(d,d));
-
-      prev += 4;
-      row  += 4;
-      rb   -= 4;
-   }
-}
-
-#endif /* PNG_INTEL_SSE_IMPLEMENTATION > 0 */
-#endif /* READ */
--- a/contrib/intel/intel_init.c
+++ b/contrib/intel/intel_init.c
@@ -1,54 +0,0 @@
-
-/* intel_init.c - SSE2 optimized filter functions
- *
- * Copyright (c) 2016 Google, Inc.
- * Written by Mike Klein and Matt Sarett
- * Derived from arm/arm_init.c, which was
- * Copyright (c) 2014,2016 Glenn Randers-Pehrson
- *
- * Last changed in libpng 1.6.22 [May 26, 2016]
- *
- * This code is released under the libpng license.
- * For conditions of distribution and use, see the disclaimer
- * and license in png.h
- */
-
-#include "../../pngpriv.h"
-
-#ifdef PNG_READ_SUPPORTED
-#if PNG_INTEL_SSE_IMPLEMENTATION > 0
-
-void
-png_init_filter_functions_sse2(png_structp pp, unsigned int bpp)
-{
-   /* The techniques used to implement each of these filters in SSE operate on
-    * one pixel at a time.
-    * So they generally speed up 3bpp images about 3x, 4bpp images about 4x.
-    * They can scale up to 6 and 8 bpp images and down to 2 bpp images,
-    * but they'd not likely have any benefit for 1bpp images.
-    * Most of these can be implemented using only MMX and 64-bit registers,
-    * but they end up a bit slower than using the equally-ubiquitous SSE2.
-   */
-   png_debug(1, "in png_init_filter_functions_sse2");
-   if (bpp == 3)
-   {
-      pp->read_filter[PNG_FILTER_VALUE_SUB-1] = png_read_filter_row_sub3_sse2;
-      pp->read_filter[PNG_FILTER_VALUE_AVG-1] = png_read_filter_row_avg3_sse2;
-      pp->read_filter[PNG_FILTER_VALUE_PAETH-1] =
-         png_read_filter_row_paeth3_sse2;
-   }
-   else if (bpp == 4)
-   {
-      pp->read_filter[PNG_FILTER_VALUE_SUB-1] = png_read_filter_row_sub4_sse2;
-      pp->read_filter[PNG_FILTER_VALUE_AVG-1] = png_read_filter_row_avg4_sse2;
-      pp->read_filter[PNG_FILTER_VALUE_PAETH-1] =
-          png_read_filter_row_paeth4_sse2;
-   }
-
-   /* No need optimize PNG_FILTER_VALUE_UP.  The compiler should
-    * autovectorize.
-    */
-}
-
-#endif /* PNG_INTEL_SSE_IMPLEMENTATION > 0 */
-#endif /* PNG_READ_SUPPORTED */
--- a/contrib/intel/intel_sse.patch
+++ b/contrib/intel/intel_sse.patch
@@ -1,164 +0,0 @@
-diff --git libpng-1.6.22-orig/configure.ac libpng-1.6.22/configure.ac
--- libpng-1.6.22-orig/configure.ac	2016-05-25 18:59:10.000000000 -0400
-+++ libpng-1.6.22/configure.ac	2016-05-25 19:48:10.631751170 -0400
-@@ -341,16 +341,50 @@ AC_ARG_ENABLE([arm-neon],
- 
- AM_CONDITIONAL([PNG_ARM_NEON],
-    [test "$enable_arm_neon" != 'no' &&
-     case "$host_cpu" in
-       arm*|aarch64*) :;;
-       *)    test "$enable_arm_neon" != '';;
-     esac])
- 
-+# INTEL
-+# =====
-+#
-+# INTEL SSE (SIMD) support.
-+
-+AC_ARG_ENABLE([intel-sse],
-+   AS_HELP_STRING([[[--enable-intel-sse]]],
-+      [Enable Intel SSE optimizations: =no/off, yes/on:]
-+      [no/off: disable the optimizations;]
-+      [yes/on: enable the optimizations.]
-+      [If not specified: determined by the compiler.]),
-+   [case "$enableval" in
-+      no|off)
-+         # disable the default enabling:
-+         AC_DEFINE([PNG_INTEL_SSE_OPT], [0],
-+                   [Disable Intel SSE optimizations])
-+         # Prevent inclusion of the assembler files below:
-+         enable_intel_sse=no;;
-+      yes|on)
-+         AC_DEFINE([PNG_INTEL_SSE_OPT], [1],
-+                   [Enable Intel SSE optimizations]);;
-+      *)
-+         AC_MSG_ERROR([--enable-intel-sse=${enable_intel_sse}: invalid value])
-+   esac])
-+
-+# Add Intel specific files to all builds where the host_cpu is Intel ('x86*')
-+# or where Intel optimizations were explicitly requested (this allows a
-+# fallback if a future host CPU does not match 'x86*')
-+AM_CONDITIONAL([PNG_INTEL_SSE],
-+   [test "$enable_intel_sse" != 'no' &&
-+    case "$host_cpu" in
-+      i?86|x86_64) :;;
-+      *)    test "$enable_intel_sse" != '';;
-+    esac])
- AC_MSG_NOTICE([[Extra options for compiler: $PNG_COPTS]])
- 
- # Config files, substituting as above
- AC_CONFIG_FILES([Makefile libpng.pc:libpng.pc.in])
- AC_CONFIG_FILES([libpng-config:libpng-config.in],
-    [chmod +x libpng-config])
- 
- AC_OUTPUT
-diff --git libpng-1.6.22-orig/Makefile.am libpng-1.6.22/Makefile.am
--- libpng-1.6.22-orig/Makefile.am	2016-05-17 18:15:12.000000000 -0400
-+++ libpng-1.6.22/Makefile.am	2016-05-25 19:48:10.631751170 -0400
-@@ -89,16 +89,20 @@ libpng@PNGLIB_MAJOR@@PNGLIB_MINOR@_la_SO
- 	pngset.c pngtrans.c pngwio.c pngwrite.c pngwtran.c pngwutil.c\
- 	png.h pngconf.h pngdebug.h pnginfo.h pngpriv.h pngstruct.h pngusr.dfa
- 
- if PNG_ARM_NEON
- libpng@PNGLIB_MAJOR@@PNGLIB_MINOR@_la_SOURCES += arm/arm_init.c\
- 	arm/filter_neon.S arm/filter_neon_intrinsics.c
- endif
- 
-+if PNG_INTEL_SSE
-+libpng@PNGLIB_MAJOR@@PNGLIB_MINOR@_la_SOURCES += contrib/intel/intel_init.c\
-+    contrib/intel/filter_sse2_intrinsics.c
-+endif
- nodist_libpng@PNGLIB_MAJOR@@PNGLIB_MINOR@_la_SOURCES = pnglibconf.h
- 
- libpng@PNGLIB_MAJOR@@PNGLIB_MINOR@_la_LDFLAGS = -no-undefined -export-dynamic \
- 	-version-number @PNGLIB_MAJOR@@PNGLIB_MINOR@:@PNGLIB_RELEASE@:0
- 
- if HAVE_LD_VERSION_SCRIPT
- #   Versioned symbols and restricted exports
- if HAVE_SOLARIS_LD
-diff --git libpng-1.6.22-orig/pngpriv.h libpng-1.6.22/pngpriv.h
--- libpng-1.6.22-orig/pngpriv.h	2016-05-25 18:59:10.000000000 -0400
-+++ libpng-1.6.22/pngpriv.h	2016-05-25 19:48:10.635751171 -0400
-@@ -177,16 +177,52 @@
- #  endif /* !PNG_ARM_NEON_IMPLEMENTATION */
- 
- #  ifndef PNG_ARM_NEON_IMPLEMENTATION
-       /* Use the intrinsics code by default. */
- #     define PNG_ARM_NEON_IMPLEMENTATION 1
- #  endif
- #endif /* PNG_ARM_NEON_OPT > 0 */
- 
-+#ifndef PNG_INTEL_SSE_OPT
-+#   ifdef PNG_INTEL_SSE
-+      /* Only check for SSE if the build configuration has been modified to
-+       * enable SSE optimizations.  This means that these optimizations will
-+       * be off by default.  See contrib/intel for more details.
-+       */
-+#     if defined(__SSE4_1__) || defined(__AVX__) || defined(__SSSE3__) || \
-+       defined(__SSE2__) || defined(_M_X64) || defined(_M_AMD64) || \
-+       (defined(_M_IX86_FP) && _M_IX86_FP >= 2)
-+#         define PNG_INTEL_SSE_OPT 1
-+#      endif
-+#   endif
-+#endif
-+
-+#if PNG_INTEL_SSE_OPT > 0
-+#   ifndef PNG_INTEL_SSE_IMPLEMENTATION
-+#      if defined(__SSE4_1__) || defined(__AVX__)
-+          /* We are not actually using AVX, but checking for AVX is the best
-+             way we can detect SSE4.1 and SSSE3 on MSVC.
-+          */
-+#         define PNG_INTEL_SSE_IMPLEMENTATION 3
-+#      elif defined(__SSSE3__)
-+#         define PNG_INTEL_SSE_IMPLEMENTATION 2
-+#      elif defined(__SSE2__) || defined(_M_X64) || defined(_M_AMD64) || \
-+       (defined(_M_IX86_FP) && _M_IX86_FP >= 2)
-+#         define PNG_INTEL_SSE_IMPLEMENTATION 1
-+#      else
-+#         define PNG_INTEL_SSE_IMPLEMENTATION 0
-+#      endif
-+#   endif
-+
-+#   if PNG_INTEL_SSE_IMPLEMENTATION > 0
-+#      define PNG_FILTER_OPTIMIZATIONS png_init_filter_functions_sse2
-+#   endif
-+#endif
-+
- /* Is this a build of a DLL where compilation of the object modules requires
-  * different preprocessor settings to those required for a simple library?  If
-  * so PNG_BUILD_DLL must be set.
-  *
-  * If libpng is used inside a DLL but that DLL does not export the libpng APIs
-  * PNG_BUILD_DLL must not be set.  To avoid the code below kicking in build a
-  * static library of libpng then link the DLL against that.
-  */
-@@ -1184,16 +1220,29 @@ PNG_INTERNAL_FUNCTION(void,png_read_filt
-     row_info, png_bytep row, png_const_bytep prev_row),PNG_EMPTY);
- PNG_INTERNAL_FUNCTION(void,png_read_filter_row_avg4_neon,(png_row_infop
-     row_info, png_bytep row, png_const_bytep prev_row),PNG_EMPTY);
- PNG_INTERNAL_FUNCTION(void,png_read_filter_row_paeth3_neon,(png_row_infop
-     row_info, png_bytep row, png_const_bytep prev_row),PNG_EMPTY);
- PNG_INTERNAL_FUNCTION(void,png_read_filter_row_paeth4_neon,(png_row_infop
-     row_info, png_bytep row, png_const_bytep prev_row),PNG_EMPTY);
- 
-+PNG_INTERNAL_FUNCTION(void,png_read_filter_row_sub3_sse2,(png_row_infop
-+    row_info, png_bytep row, png_const_bytep prev_row),PNG_EMPTY);
-+PNG_INTERNAL_FUNCTION(void,png_read_filter_row_sub4_sse2,(png_row_infop
-+    row_info, png_bytep row, png_const_bytep prev_row),PNG_EMPTY);
-+PNG_INTERNAL_FUNCTION(void,png_read_filter_row_avg3_sse2,(png_row_infop
-+    row_info, png_bytep row, png_const_bytep prev_row),PNG_EMPTY);
-+PNG_INTERNAL_FUNCTION(void,png_read_filter_row_avg4_sse2,(png_row_infop
-+    row_info, png_bytep row, png_const_bytep prev_row),PNG_EMPTY);
-+PNG_INTERNAL_FUNCTION(void,png_read_filter_row_paeth3_sse2,(png_row_infop
-+    row_info, png_bytep row, png_const_bytep prev_row),PNG_EMPTY);
-+PNG_INTERNAL_FUNCTION(void,png_read_filter_row_paeth4_sse2,(png_row_infop
-+    row_info, png_bytep row, png_const_bytep prev_row),PNG_EMPTY);
-+
- /* Choose the best filter to use and filter the row data */
- PNG_INTERNAL_FUNCTION(void,png_write_find_filter,(png_structrp png_ptr,
-     png_row_infop row_info),PNG_EMPTY);
- 
- #ifdef PNG_SEQUENTIAL_READ_SUPPORTED
- PNG_INTERNAL_FUNCTION(void,png_read_IDAT_data,(png_structrp png_ptr,
-    png_bytep output, png_alloc_size_t avail_out),PNG_EMPTY);
-    /* Read 'avail_out' bytes of data from the IDAT stream.  If the output buffer
--- a/contrib/libtests/fakepng.c
+++ b/contrib/libtests/fakepng.c
@@ -1,12 +1,4 @@
-/* Fake a PNG - just write it out directly.
- *
- * COPYRIGHT: Written by John Cunningham Bowler, 2014.
- * 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.
- *
- */
-
+/* Fake a PNG - just write it out directly. */
 #include <stdio.h>
 #include <zlib.h> /* for crc32 */

--- a/contrib/libtests/makepng.c
+++ b/contrib/libtests/makepng.c
@@ -1,9 +1,8 @@
-/* makepng.c */
-#define _ISOC99_SOURCE
-/* Copyright: */
-#define COPYRIGHT "\251 2013,2015 John Cunningham Bowler"
-/*
- * Last changed in libpng 1.6.20 [November 24, 2015]
+/* makepng.c
+ *
+ * Copyright (c) 2013 John Cunningham Bowler
+ *
+ * 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
@@ -11,8 +10,8 @@
 *
 * Make a test PNG image.  The arguments are as follows:
 *
- *    makepng [--sRGB|--linear|--1.8] [--tRNS] [--nofilters] \
- *       color-type bit-depth [file-name]
+ *  makepng [--sRGB|--linear|--1.8] [--color=<color>] color-type bit-depth \
+ *      [file-name]
 *
 * The color-type may be numeric (and must match the numbers used by the PNG
 * specification) or one of the format names listed below.  The bit-depth is the
@@ -40,8 +39,8 @@
 * 4 channels: linear combinations of, from the top-left corner clockwise,
 *    transparent, red, green, blue.
 *
- * For color-mapped images a four channel color-map is used and if --tRNS is
- * given the PNG file has a tRNS chunk, as follows:
+ * For color-mapped images a four channel color-map is used and the PNG file has
+ * a tRNS chunk, as follows:
 *
 * 1-bit: entry 0 is transparent-red, entry 1 is opaque-white
 * 2-bit: entry 0: transparent-green
@@ -54,9 +53,6 @@
 * The palette always has 2^bit-depth entries and the tRNS chunk one fewer.  The
 * image is the 1-channel diamond, but using palette index, not luminosity.
 *
- * For formats other than color-mapped ones if --tRNS is specified a tRNS chunk
- * is generated with all channels equal to the low bits of 0x0101.
- *
 * Image size is determined by the final pixel depth in bits, i.e. channels x
 * bit-depth, as follows:
 *
@@ -64,64 +60,20 @@
 * 16 bits:           256x256
 * More than 16 bits: 1024x1024
 *
- * Row filtering is the libpng default but may be turned off (the 'none' filter
- * is used on every row) with the --nofilters option.
- *
- * The images are not interlaced.
- *
- * If file-name is given then the PNG is written to that file, else it is
- * written to stdout.  Notice that stdout is not supported on systems where, by
- * default, it assumes text output; this program makes no attempt to change the
- * text mode of stdout!
- *
- *    makepng --color=<color> ...
+ * Row filtering is turned off (the 'none' filter is used on every row) and the
+ * images are not interlaced.
 *
 * If --color is given then the whole image has that color, color-mapped images
 * will have exactly one palette entry and all image files with be 16x16 in
 * size.  The color value is 1 to 4 decimal numbers as appropriate for the color
 * type.
 *
- *    makepng --small ...
- *
- * If --small is given the images are no larger than required to include every
- * possible pixel value for the format.
- *
- * For formats with pixels 8 bits or fewer in size the images consist of a
- * single row with 2^pixel-depth pixels, one of every possible value.
- *
- * For formats with 16-bit pixels a 256x256 image is generated containing every
- * possible pixel value.
- *
- * For larger pixel sizes a 256x256 image is generated where the first row
- * consists of each pixel that has identical byte values throughout the pixel
- * followed by rows where the byte values differ within the pixel.
- *
- * In all cases the pixel values are arranged in such a way that the SUB and UP
- * filters give byte sequences for maximal zlib compression.  By default (if
- * --nofilters is not given) the SUB filter is used on the first row and the UP
- * filter on all following rows.
- *
- * The --small option is meant to provide good test-case coverage, however the
- * images are not easy to examine visually.  Without the --small option the
- * images contain identical color values; the pixel values are adjusted
- * according to the gamma encoding with no gamma encoding being interpreted as
- * sRGB.
- *
- * LICENSING
- * =========
- *
- * This code is copyright of the authors, see the COPYRIGHT define above.  The
- * code is licensed as above, using the libpng license.  The code generates
- * images which are solely the product of the code; the options choose which of
- * the many possibilities to generate.  The images that result (but not the code
- * which generates them) are licensed as defined here:
- *
- * IMPORTANT: the COPYRIGHT #define must contain ISO-Latin-1 characters, the
- * IMAGE_LICENSING #define must contain UTF-8 characters.  The 'copyright'
- * symbol 0xA9U (\251) in ISO-Latin-1 encoding and 0xC20xA9 (\302\251) in UTF-8.
+ * If file-name is given then the PNG is written to that file, else it is
+ * written to stdout.  Notice that stdout is not supported on systems where, by
+ * default, it assumes text output; this program makes no attempt to change the
+ * text mode of stdout!
 */
-#define IMAGE_LICENSING "Dedicated to the public domain per Creative Commons "\
-    "license \"CC0 1.0\"; https://creativecommons.org/publicdomain/zero/1.0/"
+#define _ISOC99_SOURCE /* for strtoull */

 #include <stddef.h> /* for offsetof */
 #include <stdlib.h>
@@ -130,8 +82,6 @@
 #include <ctype.h>
 #include <math.h>
 #include <errno.h>
-#include <assert.h>
-#include <stdint.h>

 #if defined(HAVE_CONFIG_H) && !defined(PNG_NO_CONFIG_H)
 #  include <config.h>
@@ -146,25 +96,6 @@
 #  include "../../png.h"
 #endif

-#include <zlib.h>
-
-/* Work round for GCC complaints about casting a (double) function result to
- * an unsigned:
- */
-static unsigned int
-flooru(double d)
-{
-   d = floor(d);
-   return (unsigned int)d;
-}
-
-static png_byte
-floorb(double d)
-{
-   d = floor(d);
-   return (png_byte)d;
-}
-
 /* This structure is used for inserting extra chunks (the --insert argument, not
 * documented above.)
 */
@@ -176,7 +107,7 @@ typedef struct chunk_insert
   png_charp            parameters[1];
 } chunk_insert;

-static unsigned int
+static int
 channels_of_type(int color_type)
 {
   if (color_type & PNG_COLOR_MASK_PALETTE)
@@ -197,15 +128,14 @@ channels_of_type(int color_type)
   }
 }

-static unsigned int
+static int
 pixel_depth_of_type(int color_type, int bit_depth)
 {
   return channels_of_type(color_type) * bit_depth;
 }

 static unsigned int
-image_size_of_type(int color_type, int bit_depth, unsigned int *colors,
-   int small)
+image_size_of_type(int color_type, int bit_depth, unsigned int *colors)
 {
   if (*colors)
      return 16;
@@ -214,16 +144,7 @@ image_size_of_type(int color_type, int bit_depth, unsigned int *colors,
   {
      int pixel_depth = pixel_depth_of_type(color_type, bit_depth);

-      if (small)
-      {
-         if (pixel_depth <= 8) /* there will be one row */
-            return 1 << pixel_depth;
-
-         else
-            return 256;
-      }
-
-      else if (pixel_depth < 8)
+      if (pixel_depth < 8)
         return 64;

      else if (pixel_depth > 16)
@@ -296,8 +217,7 @@ generate_palette(png_colorp palette, png_bytep trans, int bit_depth,
         else
         {
            unsigned int size = 1U << (bit_depth/2); /* 2, 4 or 16 */
-            unsigned int x, y;
-            volatile unsigned int ip = 0;
+            unsigned int x, y, ip;

            for (x=0; x<size; ++x) for (y=0; y<size; ++y)
            {
@@ -361,7 +281,7 @@ set_value(png_bytep row, size_t rowbytes, png_uint_32 x, unsigned int bit_depth,
               exit(1);

            case 16:
-               value = flooru(65535*pow(value/65535.,conv)+.5);
+               value = (unsigned int)floor(65535*pow(value/65535.,conv)+.5);
               *row++ = (png_byte)(value >> 8);
               *row = (png_byte)value;
               return;
@@ -386,148 +306,15 @@ set_value(png_bytep row, size_t rowbytes, png_uint_32 x, unsigned int bit_depth,
   }
 }

-static int /* filter mask for row */
+static void
 generate_row(png_bytep row, size_t rowbytes, unsigned int y, int color_type,
   int bit_depth, png_const_bytep gamma_table, double conv,
-   unsigned int *colors, int small)
+   unsigned int *colors)
 {
-   int filters = 0; /* file *MASK*, 0 means the default, not NONE */
-   png_uint_32 size_max =
-      image_size_of_type(color_type, bit_depth, colors, small)-1;
+   png_uint_32 size_max = image_size_of_type(color_type, bit_depth, colors)-1;
   png_uint_32 depth_max = (1U << bit_depth)-1; /* up to 65536 */

-   if (colors[0] == 0) if (small)
-   {
-      unsigned int pixel_depth = pixel_depth_of_type(color_type, bit_depth);
-
-      /* For pixel depths less than 16 generate a single row containing all the
-       * possible pixel values.  For 16 generate all 65536 byte pair
-       * combinations in a 256x256 pixel array.
-       */
-      switch (pixel_depth)
-      {
-         case 1:
-            assert(y == 0 && rowbytes == 1 && size_max == 1);
-            row[0] = 0x6CU; /* binary: 01101100, only top 2 bits used */
-            filters = PNG_FILTER_NONE;
-            break;
-
-         case 2:
-            assert(y == 0 && rowbytes == 1 && size_max == 3);
-            row[0] = 0x1BU; /* binary 00011011, all bits used */
-            filters = PNG_FILTER_NONE;
-            break;
-
-         case 4:
-            assert(y == 0 && rowbytes == 8 && size_max == 15);
-            row[0] = 0x01U;
-            row[1] = 0x23U; /* SUB gives 0x22U for all following bytes */
-            row[2] = 0x45U;
-            row[3] = 0x67U;
-            row[4] = 0x89U;
-            row[5] = 0xABU;
-            row[6] = 0xCDU;
-            row[7] = 0xEFU;
-            filters = PNG_FILTER_SUB;
-            break;
-
-         case 8:
-            /* The row will have all the pixel values in order starting with
-             * '1', the SUB filter will change every byte into '1' (including
-             * the last, which generates pixel value '0').  Since the SUB filter
-             * has value 1 this should result in maximum compression.
-             */
-            assert(y == 0 && rowbytes == 256 && size_max == 255);
-            for (;;)
-            {
-               row[size_max] = 0xFFU & (size_max+1);
-               if (size_max == 0)
-                  break;
-               --size_max;
-            }
-            filters = PNG_FILTER_SUB;
-            break;
-
-         case 16:
-            /* Rows are generated such that each row has a constant difference
-             * between the first and second byte of each pixel and so that the
-             * difference increases by 1 at each row.  The rows start with the
-             * first byte value of 0 and the value increases to 255 across the
-             * row.
-             *
-             * The difference starts at 1, so the first row is:
-             *
-             *     0 1 1 2 2 3 3 4 ... 254 255 255 0
-             *
-             * This means that running the SUB filter on the first row produces:
-             *
-             *   [SUB==1] 0 1 0 1 0 1...
-             *
-             * Then the difference is 2 on the next row, giving:
-             *
-             *    0 2 1 3 2 4 3 5 ... 254 0 255 1
-             *
-             * When the UP filter is run on this libpng produces:
-             *
-             *   [UP ==2] 0 1 0 1 0 1...
-             *
-             * And so on for all the remain rows to the final two * rows:
-             *
-             *    row 254: 0 255 1 0 2 1 3 2 4 3 ... 254 253 255 254
-             *    row 255: 0   0 1 1 2 2 3 3 4 4 ... 254 254 255 255
-             */
-            assert(rowbytes == 512 && size_max == 255);
-            for (;;)
-            {
-               row[2*size_max  ] = 0xFFU & size_max;
-               row[2*size_max+1] = 0xFFU & (size_max+y+1);
-               if (size_max == 0)
-                  break;
-               --size_max;
-            }
-            /* The first row must include PNG_FILTER_UP so that libpng knows we
-             * need to keep it for the following row:
-             */
-            filters = (y == 0 ? PNG_FILTER_SUB+PNG_FILTER_UP : PNG_FILTER_UP);
-            break;
-
-         case 24:
-         case 32:
-         case 48:
-         case 64:
-            /* The rows are filled by an alogorithm similar to the above, in the
-             * first row pixel bytes are all equal, increasing from 0 by 1 for
-             * each pixel.  In the second row the bytes within a pixel are
-             * incremented 1,3,5,7,... from the previous row byte.  Using an odd
-             * number ensures all the possible byte values are used.
-             */
-            assert(size_max == 255 && rowbytes == 256*(pixel_depth>>3));
-            pixel_depth >>= 3; /* now in bytes */
-            while (rowbytes > 0)
-            {
-               const size_t pixel_index = --rowbytes/pixel_depth;
-
-               if (y == 0)
-                  row[rowbytes] = 0xFFU & pixel_index;
-
-               else
-               {
-                  const size_t byte_offset =
-                     rowbytes - pixel_index * pixel_depth;
-
-                  row[rowbytes] =
-                     0xFFU & (pixel_index + (byte_offset * 2*y) + 1);
-               }
-            }
-            filters = (y == 0 ? PNG_FILTER_SUB+PNG_FILTER_UP : PNG_FILTER_UP);
-            break;
-
-         default:
-            assert(0/*NOT REACHED*/);
-      }
-   }
-
-   else switch (channels_of_type(color_type))
+   if (colors[0] == 0) switch (channels_of_type(color_type))
   {
   /* 1 channel: a square image with a diamond, the least luminous colors are on
    *    the edge of the image, the most luminous in the center.
@@ -739,8 +526,6 @@ generate_row(png_bytep row, size_t rowbytes, unsigned int y, int color_type,
         colors[0], channels_of_type(color_type));
      exit(1);
   }
-
-   return filters;
 }


@@ -769,7 +554,7 @@ makepng_error(png_structp png_ptr, png_const_charp message)
 static int /* 0 on success, else an error code */
 write_png(const char **name, FILE *fp, int color_type, int bit_depth,
   volatile png_fixed_point gamma, chunk_insert * volatile insert,
-   unsigned int filters, unsigned int *colors, int small, int tRNS)
+   unsigned int filters, unsigned int *colors)
 {
   png_structp png_ptr = png_create_write_struct(PNG_LIBPNG_VER_STRING,
      name, makepng_error, makepng_warning);
@@ -796,15 +581,6 @@ write_png(const char **name, FILE *fp, int color_type, int bit_depth,

   /* Allow benign errors so that we can write PNGs with errors */
   png_set_benign_errors(png_ptr, 1/*allowed*/);
-
-   /* Max out the text compression level in an attempt to make the license
-    * small.   If --small then do the same for the IDAT.
-    */
-   if (small)
-      png_set_compression_level(png_ptr, Z_BEST_COMPRESSION);
-
-   png_set_text_compression_level(png_ptr, Z_BEST_COMPRESSION);
-
   png_init_io(png_ptr, fp);

   info_ptr = png_create_info_struct(png_ptr);
@@ -812,37 +588,11 @@ write_png(const char **name, FILE *fp, int color_type, int bit_depth,
      png_error(png_ptr, "OOM allocating info structure");

   {
-      const unsigned int size =
-         image_size_of_type(color_type, bit_depth, colors, small);
-      unsigned int ysize;
+      unsigned int size = image_size_of_type(color_type, bit_depth, colors);
      png_fixed_point real_gamma = 45455; /* For sRGB */
      png_byte gamma_table[256];
      double conv;

-      /* Normally images are square, but with 'small' we want to simply generate
-       * all the pixel values, or all that we reasonably can:
-       */
-      if (small)
-      {
-         const unsigned int pixel_depth =
-            pixel_depth_of_type(color_type, bit_depth);
-
-         if (pixel_depth <= 8U)
-         {
-            assert(size == (1U<<pixel_depth));
-            ysize = 1U;
-         }
-
-         else
-         {
-            assert(size == 256U);
-            ysize = 256U;
-         }
-      }
-
-      else
-         ysize = size;
-
      /* This function uses the libpng values used on read to carry extra
       * information about the gamma:
       */
@@ -875,13 +625,13 @@ write_png(const char **name, FILE *fp, int color_type, int bit_depth,
            gamma_table[0] = 0;

            for (i=1; i<255; ++i)
-               gamma_table[i] = floorb(pow(i/255.,conv) * 255 + .5);
+               gamma_table[i] = (png_byte)floor(pow(i/255.,conv) * 255 + .5);

            gamma_table[255] = 255;
         }
      }

-      png_set_IHDR(png_ptr, info_ptr, size, ysize, bit_depth, color_type,
+      png_set_IHDR(png_ptr, info_ptr, size, size, bit_depth, color_type,
         PNG_INTERLACE_NONE, PNG_COMPRESSION_TYPE_BASE, PNG_FILTER_TYPE_BASE);

      if (color_type & PNG_COLOR_MASK_PALETTE)
@@ -893,26 +643,14 @@ write_png(const char **name, FILE *fp, int color_type, int bit_depth,
         npalette = generate_palette(palette, trans, bit_depth, gamma_table,
            colors);
         png_set_PLTE(png_ptr, info_ptr, palette, npalette);
-
-         if (tRNS)
-            png_set_tRNS(png_ptr, info_ptr, trans, npalette-1,
-               NULL/*transparent color*/);
+         png_set_tRNS(png_ptr, info_ptr, trans, npalette-1,
+            NULL/*transparent color*/);

         /* Reset gamma_table to prevent the image rows being changed */
         for (npalette=0; npalette<256; ++npalette)
            gamma_table[npalette] = (png_byte)npalette;
      }

-      else if (tRNS)
-      {
-         png_color_16 col;
-
-         col.red = col.green = col.blue = col.gray =
-            0x0101U & ((1U<<bit_depth)-1U);
-         col.index = 0U;
-         png_set_tRNS(png_ptr, info_ptr, NULL/*trans*/, 1U, &col);
-      }
-
      if (gamma == PNG_DEFAULT_sRGB)
         png_set_sRGB(png_ptr, info_ptr, PNG_sRGB_INTENT_ABSOLUTE);

@@ -944,11 +682,7 @@ write_png(const char **name, FILE *fp, int color_type, int bit_depth,
      png_set_filter(png_ptr, PNG_FILTER_TYPE_BASE, filters);

      {
-#        ifdef PNG_WRITE_INTERLACING_SUPPORTED
-            int passes = png_set_interlace_handling(png_ptr);
-#        else /* !WRITE_INTERLACING */
-            int passes = 1;
-#        endif /* !WRITE_INTERLACING */
+         int passes = png_set_interlace_handling(png_ptr);
         int pass;
         png_size_t rowbytes = png_get_rowbytes(png_ptr, info_ptr);

@@ -961,15 +695,10 @@ write_png(const char **name, FILE *fp, int color_type, int bit_depth,
         {
            unsigned int y;

-            for (y=0; y<ysize; ++y)
+            for (y=0; y<size; ++y)
            {
-               unsigned int row_filters =
-                  generate_row(row, rowbytes, y, color_type, bit_depth,
-                        gamma_table, conv, colors, small);
-
-               if (row_filters != 0 && filters == PNG_ALL_FILTERS)
-                  png_set_filter(png_ptr, PNG_FILTER_TYPE_BASE, row_filters);
-
+               generate_row(row, rowbytes, y, color_type, bit_depth,
+                  gamma_table, conv, colors);
               png_write_row(png_ptr, row);
            }
         }
@@ -1098,7 +827,7 @@ static png_size_t
 load_fake(png_charp param, png_bytepp profile)
 {
   char *endptr = NULL;
-   uint64_t size = strtoull(param, &endptr, 0/*base*/);
+   unsigned long long int size = strtoull(param, &endptr, 0/*base*/);

   /* The 'fake' format is <number>*[string] */
   if (endptr != NULL && *endptr == '*')
@@ -1333,8 +1062,7 @@ insert_iTXt(png_structp png_ptr, png_infop info_ptr, int nparams,
 }

 static void
-insert_hIST(png_structp png_ptr, png_infop info_ptr, int nparams,
-      png_charpp params)
+insert_hIST(png_structp png_ptr, png_infop info_ptr, int nparams, png_charpp params)
 {
   int i;
   png_uint_16 freq[256];
@@ -1361,56 +1089,6 @@ insert_hIST(png_structp png_ptr, png_infop info_ptr, int nparams,
   png_set_hIST(png_ptr, info_ptr, freq);
 }

-static png_byte
-bval(png_const_structrp png_ptr, png_charp param, unsigned int maxval)
-{
-   char *endptr = NULL;
-   unsigned long int l = strtoul(param, &endptr, 0/*base*/);
-
-   if (param[0] && *endptr == 0 && l <= maxval)
-      return (png_byte)l;
-
-   else
-      png_error(png_ptr, "sBIT: invalid sBIT value");
-}
-
-static void
-insert_sBIT(png_structp png_ptr, png_infop info_ptr, int nparams,
-      png_charpp params)
-{
-   const int ct = png_get_color_type(png_ptr, info_ptr);
-   const int c = (ct & PNG_COLOR_MASK_COLOR ? 3 : 1) +
-      (ct & PNG_COLOR_MASK_ALPHA ? 1 : 0);
-   const unsigned int maxval =
-      ct & PNG_COLOR_MASK_PALETTE ? 8U : png_get_bit_depth(png_ptr, info_ptr);
-   png_color_8 sBIT;
-
-   if (nparams != c)
-      png_error(png_ptr, "sBIT: incorrect parameter count");
-
-   if (ct & PNG_COLOR_MASK_COLOR)
-   {
-      sBIT.red = bval(png_ptr, params[0], maxval);
-      sBIT.green = bval(png_ptr, params[1], maxval);
-      sBIT.blue = bval(png_ptr, params[2], maxval);
-      sBIT.gray = 42;
-   }
-
-   else
-   {
-      sBIT.red = sBIT.green = sBIT.blue = 42;
-      sBIT.gray = bval(png_ptr, params[0], maxval);
-   }
-
-   if (ct & PNG_COLOR_MASK_ALPHA)
-      sBIT.alpha = bval(png_ptr, params[nparams-1], maxval);
-
-   else
-      sBIT.alpha = 42;
-
-   png_set_sBIT(png_ptr, info_ptr, &sBIT);
-}
-
 #if 0
 static void
 insert_sPLT(png_structp png_ptr, png_infop info_ptr, int nparams, png_charpp params)
@@ -1538,11 +1216,6 @@ find_insert(png_const_charp what, png_charp param)
            return make_insert(what, insert_hIST, nparams, parameter_list);
         break;

-      case CHUNK(115,66,73,84): /* sBIT */
-         if (nparams <= 4)
-            return make_insert(what, insert_sBIT, nparams, parameter_list);
-         break;
-
 #if 0
      case CHUNK(115,80,76,84):  /* sPLT */
         return make_insert(what, insert_sPLT, nparams, parameter_list);
@@ -1558,80 +1231,6 @@ find_insert(png_const_charp what, png_charp param)
   return NULL;
 }

-/* This is necessary because libpng expects writeable strings for things like
- * text chunks (maybe this should be fixed...)
- */
-static png_charp
-strstash(png_const_charp foo)
-{
-   /* The program indicates a memory allocation error by crashing, this is by
-    * design.
-    */
-   if (foo != NULL)
-   {
-      png_charp bar = malloc(strlen(foo)+1);
-      return strcpy(bar, foo);
-   }
-
-   return NULL;
-}
-
-static png_charp
-strstash_list(const png_const_charp *text)
-{
-   size_t foo = 0;
-   png_charp result, bar;
-   const png_const_charp *line = text;
-
-   while (*line != NULL)
-      foo += strlen(*line++);
-
-   result = bar = malloc(foo+1);
-
-   line = text;
-   while (*line != NULL)
-   {
-      foo = strlen(*line);
-      memcpy(bar, *line++, foo);
-      bar += foo;
-   }
-
-   *bar = 0;
-   return result;
-}
-
-/* These are used to insert Copyright and Licence fields, they allow the text to
- * have \n unlike the --insert option.
- */
-static chunk_insert *
-add_tEXt(const char *key, const png_const_charp *text)
-{
-   static char what[5] = { 116, 69, 88, 116, 0 };
-   png_charp parameter_list[3];
-
-   parameter_list[0] = strstash(key);
-   parameter_list[1] = strstash_list(text);
-   parameter_list[2] = NULL;
-
-   return make_insert(what, insert_tEXt, 2, parameter_list);
-}
-
-static chunk_insert *
-add_iTXt(const char *key, const char *language, const char *language_key,
-      const png_const_charp *text)
-{
-   static char what[5] = { 105, 84, 88, 116, 0 };
-   png_charp parameter_list[5];
-
-   parameter_list[0] = strstash(key);
-   parameter_list[1] = strstash(language);
-   parameter_list[2] = strstash(language_key);
-   parameter_list[3] = strstash_list(text);
-   parameter_list[4] = NULL;
-
-   return make_insert(what, insert_iTXt, 4, parameter_list);
-}
-
 /* This is a not-very-good parser for a sequence of numbers (including 0).  It
 * doesn't accept some apparently valid things, but it accepts all the sensible
 * combinations.
@@ -1681,8 +1280,6 @@ main(int argc, char **argv)
   const char *file_name = NULL;
   int color_type = 8; /* invalid */
   int bit_depth = 32; /* invalid */
-   int small = 0; /* make full size images */
-   int tRNS = 0; /* don't output a tRNS chunk */
   unsigned int colors[5];
   unsigned int filters = PNG_ALL_FILTERS;
   png_fixed_point gamma = 0; /* not set */
@@ -1695,18 +1292,6 @@ main(int argc, char **argv)
   {
      char *arg = *++argv;

-      if (strcmp(arg, "--small") == 0)
-      {
-         small = 1;
-         continue;
-      }
-
-      if (strcmp(arg, "--tRNS") == 0)
-      {
-         tRNS = 1;
-         continue;
-      }
-
      if (strcmp(arg, "--sRGB") == 0)
      {
         gamma = PNG_DEFAULT_sRGB;
@@ -1847,10 +1432,9 @@ main(int argc, char **argv)

   if (color_type == 8 || bit_depth == 32)
   {
-      fprintf(stderr, "usage: makepng [--small] [--sRGB|--linear|--1.8] "
+      fprintf(stderr, "usage: makepng [--sRGB|--linear|--1.8] "
         "[--color=...] color-type bit-depth [file-name]\n"
-         "  Make a test PNG file, by default writes to stdout.\n"
-         "  Other options are available, UTSL.\n");
+         "  Make a test PNG file, by default writes to stdout.\n");
      exit(1);
   }

@@ -1869,19 +1453,10 @@ main(int argc, char **argv)
         }
   }

-   /* small and colors are incomparible (will probably crash if both are used at
-    * the same time!)
-    */
-   if (small && colors[0] != 0)
-   {
-      fprintf(stderr, "makepng: --color --small: only one at a time!\n");
-      exit(1);
-   }
-
   /* Restrict the filters for more speed to those we know are used for the
    * generated images.
    */
-   if (filters == PNG_ALL_FILTERS && !small/*small provides defaults*/)
+   if (filters == PNG_ALL_FILTERS)
   {
      if ((color_type & PNG_COLOR_MASK_PALETTE) != 0 || bit_depth < 8)
         filters = PNG_FILTER_NONE;
@@ -1899,39 +1474,9 @@ main(int argc, char **argv)
         filters &= ~PNG_FILTER_NONE;
   }

-   /* Insert standard copyright and licence text. */
-   {
-      static png_const_charp copyright[] =
-      {
-         COPYRIGHT, /* ISO-Latin-1 */
-         NULL
-      };
-      static png_const_charp licensing[] =
-      {
-         IMAGE_LICENSING, /* UTF-8 */
-         NULL
-      };
-
-      chunk_insert *new_insert;
-
-      new_insert = add_tEXt("Copyright", copyright);
-      if (new_insert != NULL)
-      {
-         *insert_ptr = new_insert;
-         insert_ptr = &new_insert->next;
-      }
-
-      new_insert = add_iTXt("Licensing", "en", NULL, licensing);
-      if (new_insert != NULL)
-      {
-         *insert_ptr = new_insert;
-         insert_ptr = &new_insert->next;
-      }
-   }
-
   {
      int ret = write_png(&file_name, fp, color_type, bit_depth, gamma,
-         head_insert, filters, colors, small, tRNS);
+         head_insert, filters, colors);

      if (ret != 0 && file_name != NULL)
         remove(file_name);
--- a/contrib/libtests/pngimage.c
+++ b/contrib/libtests/pngimage.c
@@ -1,8 +1,8 @@
 /* pngimage.c
 *
- * Copyright (c) 2015,2016 John Cunningham Bowler
+ * Copyright (c) 2015 John Cunningham Bowler
 *
- * Last changed in libpng 1.6.22 [May 26, 2016]
+ * Last changed in libpng 1.6.18 [July 23, 2015]
 *
 * This code is released under the libpng license.
 * For conditions of distribution and use, see the disclaimer
@@ -36,17 +36,7 @@
 #  include <setjmp.h> /* because png.h did *not* include this */
 #endif

-/* 1.6.1 added support for the configure test harness, which uses 77 to indicate
- * a skipped test, in earlier versions we need to succeed on a skipped test, so:
- */
-#if PNG_LIBPNG_VER >= 10601 && defined(HAVE_CONFIG_H)
-#  define SKIP 77
-#else
-#  define SKIP 0
-#endif
-
-#if defined(PNG_INFO_IMAGE_SUPPORTED) && defined(PNG_SEQUENTIAL_READ_SUPPORTED)\
-    && (defined(PNG_READ_PNG_SUPPORTED) || PNG_LIBPNG_VER < 10700)
+#if defined(PNG_INFO_IMAGE_SUPPORTED) && defined(PNG_SEQUENTIAL_READ_SUPPORTED)
 /* If a transform is valid on both read and write this implies that if the
 * transform is applied to read it must also be applied on write to produce
 * meaningful data.  This is because these transforms when performed on read
@@ -246,12 +236,10 @@ static struct transform_info
       */
 #endif
 #ifdef PNG_READ_SCALE_16_TO_8_SUPPORTED
-   T(SCALE_16,            NONE, X,   X,   16,  R),
+   T(SCALE_16,            NONE, X,   X,   16,  R)
      /* scales 16-bit components to 8-bits. */
 #endif

-   { NULL /*name*/, 0, 0, 0, 0, 0, 0, 0/*!tested*/ }
-
 #undef T
 };

@@ -306,7 +294,7 @@ transform_name(int t)

   t &= -t; /* first set bit */

-   for (i=0; i<TTABLE_SIZE; ++i) if (transform_info[i].name != NULL)
+   for (i=0; i<TTABLE_SIZE; ++i)
   {
      if ((transform_info[i].transform & t) != 0)
         return transform_info[i].name;
@@ -327,7 +315,7 @@ validate_T(void)
 {
   unsigned int i;

-   for (i=0; i<TTABLE_SIZE; ++i) if (transform_info[i].name != NULL)
+   for (i=0; i<TTABLE_SIZE; ++i)
   {
      if (transform_info[i].when & TRANSFORM_R)
         read_transforms |= transform_info[i].transform;
@@ -517,7 +505,6 @@ typedef enum
 #define SKIP_BUGS       0x100 /* Skip over known bugs */
 #define LOG_SKIPPED     0x200 /* Log skipped bugs */
 #define FIND_BAD_COMBOS 0x400 /* Attempt to deduce bad combos */
-#define LIST_COMBOS     0x800 /* List combos by name */

 /* Result masks apply to the result bits in the 'results' field below; these
 * bits are simple 1U<<error_level.  A pass requires either nothing worse than
@@ -703,35 +690,7 @@ display_log(struct display *dp, error_level level, const char *fmt, ...)
         int tr = dp->transforms;

         if (is_combo(tr))
-         {
-            if (dp->options & LIST_COMBOS)
-            {
-               int trx = tr;
-
-               fprintf(stderr, "(");
-               if (trx)
-               {
-                  int start = 0;
-
-                  while (trx)
-                  {
-                     int trz = trx & -trx;
-
-                     if (start) fprintf(stderr, "+");
-                     fprintf(stderr, "%s", transform_name(trz));
-                     start = 1;
-                     trx &= ~trz;
-                  }
-               }
-
-               else
-                  fprintf(stderr, "-");
-               fprintf(stderr, ")");
-            }
-
-            else
-               fprintf(stderr, "(0x%x)", tr);
-         }
+            fprintf(stderr, "(0x%x)", tr);

         else
            fprintf(stderr, "(%s)", transform_name(tr));
@@ -951,13 +910,13 @@ update_display(struct display *dp)
      int bd = dp->bit_depth;
      unsigned int i;

-      for (i=0; i<TTABLE_SIZE; ++i) if (transform_info[i].name != NULL)
+      for (i=0; i<TTABLE_SIZE; ++i)
      {
         int transform = transform_info[i].transform;

         if ((transform_info[i].valid_chunks == 0 ||
               (transform_info[i].valid_chunks & chunks) != 0) &&
-            (transform_info[i].color_mask_required & ct) ==
+            (transform_info[i].color_mask_required & ct) == 
               transform_info[i].color_mask_required &&
            (transform_info[i].color_mask_absent & ct) == 0 &&
            (transform_info[i].bit_depths & bd) != 0 &&
@@ -976,6 +935,9 @@ update_display(struct display *dp)

      dp->active_transforms = active;
      dp->ignored_transforms = inactive; /* excluding write-only transforms */
+
+      if (active == 0)
+         display_log(dp, INTERNAL_ERROR, "bad transform table");
   }
 }

@@ -1015,7 +977,7 @@ compare_read(struct display *dp, int applied_transforms)
   {
      unsigned long chunks =
         png_get_valid(dp->read_pp, dp->read_ip, 0xffffffff);
-
+      
      if (chunks != dp->chunks)
         display_log(dp, APP_FAIL, "PNG chunks changed from 0x%lx to 0x%lx",
            (unsigned long)dp->chunks, chunks);
@@ -1626,12 +1588,6 @@ main(const int argc, const char * const * const argv)
      else if (strcmp(name, "--nofind-bad-combos") == 0)
         d.options &= ~FIND_BAD_COMBOS;

-      else if (strcmp(name, "--list-combos") == 0)
-         d.options |= LIST_COMBOS;
-
-      else if (strcmp(name, "--nolist-combos") == 0)
-         d.options &= ~LIST_COMBOS;
-
      else if (name[0] == '-' && name[1] == '-')
      {
         fprintf(stderr, "pngimage: %s: unknown option\n", name);
@@ -1686,11 +1642,11 @@ main(const int argc, const char * const * const argv)
      return errors != 0;
   }
 }
-#else /* !INFO_IMAGE || !SEQUENTIAL_READ || !READ_PNG*/
+#else /* !PNG_INFO_IMAGE_SUPPORTED || !PNG_READ_SUPPORTED */
 int
 main(void)
 {
   fprintf(stderr, "pngimage: no support for png_read/write_image\n");
-   return SKIP;
+   return 77;
 }
 #endif
--- a/contrib/libtests/pngstest-errors.h
+++ b/contrib/libtests/pngstest-errors.h
@@ -1,165 +0,0 @@
-/* contrib/libtests/pngstest-errors.h
- *
- * BUILT USING: libpng version 1.6.19beta03 - September 25, 2015
- *
- * This code is released under the libpng license.
- * For conditions of distribution and use, see the disclaimer
- * and license in png.h
- *
- * THIS IS A MACHINE GENERATED FILE: do not edit it directly!
- * Instead run:
- *
- *    pngstest --accumulate
- *
- * on as many PNG files as possible; at least PNGSuite and
- * contrib/libtests/testpngs.
- */
-static png_uint_16 gpc_error[16/*in*/][16/*out*/][4/*a*/] =
-{
- { /* input: sRGB-gray */
-  { 0, 0, 0, 0 }, { 0, 0, 0, 0 }, { 0, 0, 0, 0 }, { 0, 0, 0, 0 },
-  { 0, 0, 372, 0 }, { 0, 0, 372, 0 }, { 0, 0, 372, 0 }, { 0, 0, 372, 0 },
-  { 0, 0, 0, 0 }, { 0, 0, 0, 0 }, { 0, 0, 0, 0 }, { 0, 0, 0, 0 },
-  { 0, 0, 0, 0 }, { 0, 0, 0, 0 }, { 0, 0, 0, 0 }, { 0, 0, 0, 0 }
- }, { /* input: sRGB-gray+alpha */
-  { 0, 19, 0, 0 }, { 0, 0, 0, 0 }, { 0, 20, 0, 0 }, { 0, 0, 0, 0 },
-  { 0, 897, 788, 0 }, { 0, 897, 788, 0 }, { 0, 897, 788, 0 }, { 0, 897, 788, 0 },
-  { 0, 0, 0, 0 }, { 0, 0, 0, 0 }, { 0, 0, 0, 0 }, { 0, 0, 0, 0 },
-  { 0, 0, 0, 0 }, { 0, 0, 0, 0 }, { 0, 0, 0, 0 }, { 0, 0, 0, 0 }
- }, { /* input: sRGB-rgb */
-  { 0, 0, 19, 0 }, { 0, 0, 19, 0 }, { 0, 0, 0, 0 }, { 0, 0, 0, 0 },
-  { 0, 0, 893, 0 }, { 0, 0, 893, 0 }, { 0, 0, 811, 0 }, { 0, 0, 811, 0 },
-  { 0, 0, 0, 0 }, { 0, 0, 0, 0 }, { 0, 0, 0, 0 }, { 0, 0, 0, 0 },
-  { 0, 0, 0, 0 }, { 0, 0, 0, 0 }, { 0, 0, 0, 0 }, { 0, 0, 0, 0 }
- }, { /* input: sRGB-rgb+alpha */
-  { 0, 16, 17, 0 }, { 0, 17, 17, 0 }, { 0, 19, 0, 0 }, { 0, 0, 0, 0 },
-  { 0, 850, 875, 0 }, { 0, 850, 875, 0 }, { 0, 897, 788, 0 }, { 0, 897, 788, 0 },
-  { 0, 0, 0, 0 }, { 0, 0, 0, 0 }, { 0, 0, 0, 0 }, { 0, 0, 0, 0 },
-  { 0, 0, 0, 0 }, { 0, 0, 0, 0 }, { 0, 0, 0, 0 }, { 0, 0, 0, 0 }
- }, { /* input: linear-gray */
-  { 0, 0, 9, 0 }, { 0, 0, 9, 0 }, { 0, 0, 9, 0 }, { 0, 0, 9, 0 },
-  { 0, 0, 0, 0 }, { 0, 0, 0, 0 }, { 0, 0, 0, 0 }, { 0, 0, 0, 0 },
-  { 0, 0, 0, 0 }, { 0, 0, 0, 0 }, { 0, 0, 0, 0 }, { 0, 0, 0, 0 },
-  { 0, 0, 0, 0 }, { 0, 0, 0, 0 }, { 0, 0, 0, 0 }, { 0, 0, 0, 0 }
- }, { /* input: linear-gray+alpha */
-  { 0, 74, 9, 0 }, { 0, 20, 9, 0 }, { 0, 74, 9, 0 }, { 0, 20, 9, 0 },
-  { 0, 0, 0, 0 }, { 0, 1, 0, 0 }, { 0, 0, 0, 0 }, { 0, 1, 0, 0 },
-  { 0, 0, 0, 0 }, { 0, 0, 0, 0 }, { 0, 0, 0, 0 }, { 0, 0, 0, 0 },
-  { 0, 0, 0, 0 }, { 0, 0, 0, 0 }, { 0, 0, 0, 0 }, { 0, 0, 0, 0 }
- }, { /* input: linear-rgb */
-  { 0, 0, 9, 0 }, { 0, 0, 9, 0 }, { 0, 0, 9, 0 }, { 0, 0, 9, 0 },
-  { 0, 0, 4, 0 }, { 0, 0, 4, 0 }, { 0, 0, 0, 0 }, { 0, 0, 0, 0 },
-  { 0, 0, 0, 0 }, { 0, 0, 0, 0 }, { 0, 0, 0, 0 }, { 0, 0, 0, 0 },
-  { 0, 0, 0, 0 }, { 0, 0, 0, 0 }, { 0, 0, 0, 0 }, { 0, 0, 0, 0 }
- }, { /* input: linear-rgb+alpha */
-  { 0, 126, 143, 0 }, { 0, 11, 7, 0 }, { 0, 74, 9, 0 }, { 0, 17, 9, 0 },
-  { 0, 4, 4, 0 }, { 0, 5, 4, 0 }, { 0, 0, 0, 0 }, { 0, 1, 0, 0 },
-  { 0, 0, 0, 0 }, { 0, 0, 0, 0 }, { 0, 0, 0, 0 }, { 0, 0, 0, 0 },
-  { 0, 0, 0, 0 }, { 0, 0, 0, 0 }, { 0, 0, 0, 0 }, { 0, 0, 0, 0 }
- }, { /* input: color-mapped-sRGB-gray */
-  { 0, 0, 0, 0 }, { 0, 0, 0, 0 }, { 0, 0, 0, 0 }, { 0, 0, 0, 0 },
-  { 0, 0, 0, 0 }, { 0, 0, 0, 0 }, { 0, 0, 0, 0 }, { 0, 0, 0, 0 },
-  { 0, 0, 0, 0 }, { 0, 0, 0, 0 }, { 0, 0, 0, 0 }, { 0, 0, 0, 0 },
-  { 0, 0, 0, 0 }, { 0, 0, 0, 0 }, { 0, 0, 0, 0 }, { 0, 0, 0, 0 }
- }, { /* input: color-mapped-sRGB-gray+alpha */
-  { 0, 0, 0, 0 }, { 0, 0, 0, 0 }, { 0, 0, 0, 0 }, { 0, 0, 0, 0 },
-  { 0, 0, 0, 0 }, { 0, 0, 0, 0 }, { 0, 0, 0, 0 }, { 0, 0, 0, 0 },
-  { 0, 0, 0, 0 }, { 0, 0, 0, 0 }, { 0, 0, 0, 0 }, { 0, 0, 0, 0 },
-  { 0, 0, 0, 0 }, { 0, 0, 0, 0 }, { 0, 0, 0, 0 }, { 0, 0, 0, 0 }
- }, { /* input: color-mapped-sRGB-rgb */
-  { 0, 0, 13, 0 }, { 0, 0, 13, 0 }, { 0, 0, 9, 0 }, { 0, 0, 9, 0 },
-  { 0, 0, 673, 0 }, { 0, 0, 673, 0 }, { 0, 0, 674, 0 }, { 0, 0, 674, 0 },
-  { 0, 0, 1, 0 }, { 0, 0, 1, 0 }, { 0, 0, 0, 0 }, { 0, 0, 0, 0 },
-  { 0, 0, 460, 0 }, { 0, 0, 460, 0 }, { 0, 0, 263, 0 }, { 0, 0, 263, 0 }
- }, { /* input: color-mapped-sRGB-rgb+alpha */
-  { 0, 6, 8, 0 }, { 0, 7, 8, 0 }, { 0, 75, 9, 0 }, { 0, 9, 9, 0 },
-  { 0, 585, 427, 0 }, { 0, 585, 427, 0 }, { 0, 717, 514, 0 }, { 0, 717, 514, 0 },
-  { 0, 1, 1, 0 }, { 0, 1, 1, 0 }, { 0, 1, 0, 0 }, { 0, 0, 0, 0 },
-  { 0, 13323, 460, 0 }, { 0, 427, 460, 0 }, { 0, 16480, 263, 0 }, { 0, 243, 263, 0 }
- }, { /* input: color-mapped-linear-gray */
-  { 0, 0, 0, 0 }, { 0, 0, 0, 0 }, { 0, 0, 0, 0 }, { 0, 0, 0, 0 },
-  { 0, 0, 0, 0 }, { 0, 0, 0, 0 }, { 0, 0, 0, 0 }, { 0, 0, 0, 0 },
-  { 0, 0, 0, 0 }, { 0, 0, 0, 0 }, { 0, 0, 0, 0 }, { 0, 0, 0, 0 },
-  { 0, 0, 282, 0 }, { 0, 0, 0, 0 }, { 0, 0, 0, 0 }, { 0, 0, 0, 0 }
- }, { /* input: color-mapped-linear-gray+alpha */
-  { 0, 0, 0, 0 }, { 0, 0, 0, 0 }, { 0, 0, 0, 0 }, { 0, 0, 0, 0 },
-  { 0, 0, 0, 0 }, { 0, 0, 0, 0 }, { 0, 0, 0, 0 }, { 0, 0, 0, 0 },
-  { 0, 0, 0, 0 }, { 0, 0, 0, 0 }, { 0, 0, 0, 0 }, { 0, 0, 0, 0 },
-  { 0, 0, 0, 0 }, { 0, 253, 282, 0 }, { 0, 0, 0, 0 }, { 0, 0, 0, 0 }
- }, { /* input: color-mapped-linear-rgb */
-  { 0, 0, 0, 0 }, { 0, 0, 0, 0 }, { 0, 0, 0, 0 }, { 0, 0, 0, 0 },
-  { 0, 0, 0, 0 }, { 0, 0, 0, 0 }, { 0, 0, 0, 0 }, { 0, 0, 0, 0 },
-  { 0, 0, 0, 0 }, { 0, 0, 0, 0 }, { 0, 0, 0, 0 }, { 0, 0, 0, 0 },
-  { 0, 0, 0, 0 }, { 0, 0, 0, 0 }, { 0, 0, 265, 0 }, { 0, 0, 0, 0 }
- }, { /* input: color-mapped-linear-rgb+alpha */
-  { 0, 0, 0, 0 }, { 0, 0, 0, 0 }, { 0, 0, 0, 0 }, { 0, 0, 0, 0 },
-  { 0, 0, 0, 0 }, { 0, 0, 0, 0 }, { 0, 0, 0, 0 }, { 0, 0, 0, 0 },
-  { 0, 0, 0, 0 }, { 0, 0, 0, 0 }, { 0, 0, 0, 0 }, { 0, 0, 0, 0 },
-  { 0, 0, 0, 0 }, { 0, 0, 0, 0 }, { 0, 0, 0, 0 }, { 0, 243, 265, 0 }
- }
-};
-static png_uint_16 gpc_error_via_linear[16][4/*out*/][4] =
-{
- { /* input: sRGB-gray */
-  { 0, 0, 7, 0 }, { 0, 0, 7, 0 }, { 0, 0, 7, 0 }, { 0, 0, 7, 0 }
- }, { /* input: sRGB-gray+alpha */
-  { 0, 15, 15, 0 }, { 0, 186, 15, 0 }, { 0, 15, 15, 0 }, { 0, 186, 15, 0 }
- }, { /* input: sRGB-rgb */
-  { 0, 0, 20, 0 }, { 0, 0, 20, 0 }, { 0, 0, 15, 0 }, { 0, 0, 15, 0 }
- }, { /* input: sRGB-rgb+alpha */
-  { 0, 16, 17, 0 }, { 0, 187, 17, 0 }, { 0, 15, 15, 0 }, { 0, 186, 15, 0 }
- }, { /* input: linear-gray */
-  { 0, 0, 1, 0 }, { 0, 0, 1, 0 }, { 0, 0, 1, 0 }, { 0, 0, 1, 0 }
- }, { /* input: linear-gray+alpha */
-  { 0, 1, 1, 0 }, { 0, 1, 1, 0 }, { 0, 1, 1, 0 }, { 0, 1, 1, 0 }
- }, { /* input: linear-rgb */
-  { 0, 0, 1, 0 }, { 0, 0, 1, 0 }, { 0, 0, 1, 0 }, { 0, 0, 1, 0 }
- }, { /* input: linear-rgb+alpha */
-  { 0, 1, 1, 0 }, { 0, 9, 1, 0 }, { 0, 1, 1, 0 }, { 0, 1, 1, 0 }
- }, { /* input: color-mapped-sRGB-gray */
-  { 0, 0, 0, 0 }, { 0, 0, 0, 0 }, { 0, 0, 0, 0 }, { 0, 0, 0, 0 }
- }, { /* input: color-mapped-sRGB-gray+alpha */
-  { 0, 0, 0, 0 }, { 0, 0, 0, 0 }, { 0, 0, 0, 0 }, { 0, 0, 0, 0 }
- }, { /* input: color-mapped-sRGB-rgb */
-  { 0, 0, 13, 0 }, { 0, 0, 13, 0 }, { 0, 0, 14, 0 }, { 0, 0, 14, 0 }
- }, { /* input: color-mapped-sRGB-rgb+alpha */
-  { 0, 4, 8, 0 }, { 0, 9, 8, 0 }, { 0, 9, 5, 0 }, { 0, 32, 5, 0 }
- }, { /* input: color-mapped-linear-gray */
-  { 0, 0, 0, 0 }, { 0, 0, 0, 0 }, { 0, 0, 0, 0 }, { 0, 0, 0, 0 }
- }, { /* input: color-mapped-linear-gray+alpha */
-  { 0, 0, 0, 0 }, { 0, 0, 0, 0 }, { 0, 0, 0, 0 }, { 0, 0, 0, 0 }
- }, { /* input: color-mapped-linear-rgb */
-  { 0, 0, 0, 0 }, { 0, 0, 0, 0 }, { 0, 0, 0, 0 }, { 0, 0, 0, 0 }
- }, { /* input: color-mapped-linear-rgb+alpha */
-  { 0, 0, 0, 0 }, { 0, 0, 0, 0 }, { 0, 0, 0, 0 }, { 0, 0, 0, 0 }
- }
-};
-static png_uint_16 gpc_error_to_colormap[8/*i*/][8/*o*/][4] =
-{
- { /* input: sRGB-gray */
-  { 0, 0, 9, 0 }, { 0, 0, 9, 0 }, { 0, 0, 9, 0 }, { 0, 0, 9, 0 },
-  { 0, 0, 560, 0 }, { 0, 0, 560, 0 }, { 0, 0, 560, 0 }, { 0, 0, 560, 0 }
- }, { /* input: sRGB-gray+alpha */
-  { 0, 19, 9, 0 }, { 0, 255, 9, 25 }, { 0, 88, 9, 0 }, { 0, 255, 9, 25 },
-  { 0, 1012, 928, 0 }, { 0, 16026, 928, 6425 }, { 0, 1012, 928, 0 }, { 0, 16026, 928, 6425 }
- }, { /* input: sRGB-rgb */
-  { 0, 0, 19, 0 }, { 0, 0, 19, 0 }, { 0, 0, 25, 0 }, { 0, 0, 25, 0 },
-  { 0, 0, 962, 0 }, { 0, 0, 962, 0 }, { 0, 0, 13677, 0 }, { 0, 0, 13677, 0 }
- }, { /* input: sRGB-rgb+alpha */
-  { 0, 63, 77, 0 }, { 0, 255, 19, 25 }, { 0, 225, 25, 0 }, { 0, 255, 25, 67 },
-  { 0, 17534, 18491, 0 }, { 0, 15736, 2824, 6425 }, { 0, 14019, 13677, 0 }, { 0, 50115, 13677, 17219 }
- }, { /* input: linear-gray */
-  { 0, 0, 73, 0 }, { 0, 0, 73, 0 }, { 0, 0, 73, 0 }, { 0, 0, 73, 0 },
-  { 0, 0, 18817, 0 }, { 0, 0, 18817, 0 }, { 0, 0, 18817, 0 }, { 0, 0, 18817, 0 }
- }, { /* input: linear-gray+alpha */
-  { 0, 74, 74, 0 }, { 0, 255, 74, 25 }, { 0, 99, 74, 0 }, { 0, 255, 74, 25 },
-  { 0, 18919, 18907, 0 }, { 0, 24549, 18907, 6553 }, { 0, 18919, 18907, 0 }, { 0, 24549, 18907, 6553 }
- }, { /* input: linear-rgb */
-  { 0, 0, 73, 0 }, { 0, 0, 73, 0 }, { 0, 0, 98, 0 }, { 0, 0, 98, 0 },
-  { 0, 0, 18664, 0 }, { 0, 0, 18664, 0 }, { 0, 0, 24998, 0 }, { 0, 0, 24998, 0 }
- }, { /* input: linear-rgb+alpha */
-  { 0, 181, 196, 0 }, { 0, 255, 61, 25 }, { 206, 187, 98, 0 }, { 0, 255, 98, 67 },
-  { 0, 18141, 18137, 0 }, { 0, 17494, 17504, 6553 }, { 0, 24979, 24992, 0 }, { 0, 49172, 24992, 17347 }
- }
-};
-/* END MACHINE GENERATED */
--- a/contrib/libtests/pngstest.c
+++ b/contrib/libtests/pngstest.c
@@ -1,9 +1,9 @@
 /*-
 * pngstest.c
 *
- * Copyright (c) 2013-2016 John Cunningham Bowler
+ * Copyright (c) 2013-2015 John Cunningham Bowler
 *
- * Last changed in libpng 1.6.22 [May 26, 2016]
+ * Last changed in libpng 1.6.18 [July 23, 2015]
 *
 * This code is released under the libpng license.
 * For conditions of distribution and use, see the disclaimer
@@ -26,15 +26,6 @@
 #  include <config.h>
 #endif

-/* 1.6.1 added support for the configure test harness, which uses 77 to indicate
- * a skipped test, in earlier versions we need to succeed on a skipped test, so:
- */
-#if PNG_LIBPNG_VER >= 10601 && defined(HAVE_CONFIG_H)
-#  define SKIP 77
-#else
-#  define SKIP 0
-#endif
-
 /* Define the following to use this test against your installed libpng, rather
 * than the one being built here:
 */
@@ -108,18 +99,10 @@ make_random_bytes(png_uint_32* seed, void* pv, size_t size)
   seed[1] = u1;
 }

-static png_uint_32 color_seed[2];
-
-static void
-reseed(void)
-{
-   color_seed[0] = 0x12345678U;
-   color_seed[1] = 0x9abcdefU;
-}
-
 static void
 random_color(png_colorp color)
 {
+   static png_uint_32 color_seed[2] = { 0x12345678, 0x9abcdef };
   make_random_bytes(color_seed, color, sizeof *color);
 }

@@ -324,7 +307,7 @@ compare_16bit(int v1, int v2, int error_limit, int multiple_algorithms)
 }
 #endif /* unused */

-#define USE_FILE 1       /* else memory */
+#define READ_FILE 1      /* else memory */
 #define USE_STDIO 2      /* else use file name */
 #define STRICT 4         /* fail on warnings too */
 #define VERBOSE 8
@@ -333,19 +316,16 @@ compare_16bit(int v1, int v2, int error_limit, int multiple_algorithms)
 #define ACCUMULATE 64
 #define FAST_WRITE 128
 #define sRGB_16BIT 256
-#define NO_RESEED  512   /* do not reseed on each new file */
-#define GBG_ERROR 1024   /* do not ignore the gamma+background_rgb_to_gray
-                          * libpng warning. */

 static void
 print_opts(png_uint_32 opts)
 {
-   if (opts & USE_FILE)
+   if (opts & READ_FILE)
      printf(" --file");
   if (opts & USE_STDIO)
      printf(" --stdio");
-   if (!(opts & STRICT))
-      printf(" --nostrict");
+   if (opts & STRICT)
+      printf(" --strict");
   if (opts & VERBOSE)
      printf(" --verbose");
   if (opts & KEEP_TMPFILES)
@@ -358,12 +338,6 @@ print_opts(png_uint_32 opts)
      printf(" --slow");
   if (opts & sRGB_16BIT)
      printf(" --sRGB-16bit");
-   if (opts & NO_RESEED)
-      printf(" --noreseed");
-#if PNG_LIBPNG_VER < 10700 /* else on by default */
-   if (opts & GBG_ERROR)
-      printf(" --fault-gbg-warning");
-#endif
 }

 #define FORMAT_NO_CHANGE 0x80000000 /* additional flag */
@@ -767,15 +741,8 @@ checkopaque(Image *image)
      return logerror(image, image->file_name, ": opaque not NULL", "");
   }

-   /* Separate out the gamma+background_rgb_to_gray warning because it may
-    * produce opaque component errors:
-    */
-   else if (image->image.warning_or_error != 0 &&
-            (strcmp(image->image.message,
-               "libpng does not support gamma+background+rgb_to_gray") == 0 ?
-                  (image->opts & GBG_ERROR) != 0 : (image->opts & STRICT) != 0))
-      return logerror(image, image->file_name, (image->opts & GBG_ERROR) != 0 ?
-                      " --fault-gbg-warning" : " --strict", "");
+   else if (image->image.warning_or_error != 0 && (image->opts & STRICT) != 0)
+      return logerror(image, image->file_name, " --strict", "");

   else
      return 1;
@@ -2017,7 +1984,156 @@ static void (* const gpc_fn_colormapped[8/*in*/][8/*out*/])
 * gpc_error_to_colormap.
 */
 #if PNG_FORMAT_FLAG_COLORMAP == 8 /* extra check also required */
-#  include "pngstest-errors.h" /* machine generated */
+/* START MACHINE GENERATED */
+static png_uint_16 gpc_error[16/*in*/][16/*out*/][4/*a*/] =
+{
+ { /* input: sRGB-gray */
+  { 0, 0, 0, 0 }, { 0, 0, 0, 0 }, { 0, 0, 0, 0 }, { 0, 0, 0, 0 },
+  { 0, 0, 372, 0 }, { 0, 0, 372, 0 }, { 0, 0, 372, 0 }, { 0, 0, 372, 0 },
+  { 0, 0, 0, 0 }, { 0, 0, 0, 0 }, { 0, 0, 0, 0 }, { 0, 0, 0, 0 },
+  { 0, 0, 0, 0 }, { 0, 0, 0, 0 }, { 0, 0, 0, 0 }, { 0, 0, 0, 0 }
+ }, { /* input: sRGB-gray+alpha */
+  { 0, 18, 0, 0 }, { 0, 0, 0, 0 }, { 0, 20, 0, 0 }, { 0, 0, 0, 0 },
+  { 0, 897, 788, 0 }, { 0, 897, 788, 0 }, { 0, 897, 788, 0 }, { 0, 897, 788, 0 },
+  { 0, 0, 0, 0 }, { 0, 0, 0, 0 }, { 0, 0, 0, 0 }, { 0, 0, 0, 0 },
+  { 0, 0, 0, 0 }, { 0, 0, 0, 0 }, { 0, 0, 0, 0 }, { 0, 0, 0, 0 }
+ }, { /* input: sRGB-rgb */
+  { 0, 0, 19, 0 }, { 0, 0, 19, 0 }, { 0, 0, 0, 0 }, { 0, 0, 0, 0 },
+  { 0, 0, 893, 0 }, { 0, 0, 893, 0 }, { 0, 0, 811, 0 }, { 0, 0, 811, 0 },
+  { 0, 0, 0, 0 }, { 0, 0, 0, 0 }, { 0, 0, 0, 0 }, { 0, 0, 0, 0 },
+  { 0, 0, 0, 0 }, { 0, 0, 0, 0 }, { 0, 0, 0, 0 }, { 0, 0, 0, 0 }
+ }, { /* input: sRGB-rgb+alpha */
+  { 0, 4, 13, 0 }, { 0, 14, 13, 0 }, { 0, 19, 0, 0 }, { 0, 0, 0, 0 },
+  { 0, 832, 764, 0 }, { 0, 832, 764, 0 }, { 0, 897, 788, 0 }, { 0, 897, 788, 0 },
+  { 0, 0, 0, 0 }, { 0, 0, 0, 0 }, { 0, 0, 0, 0 }, { 0, 0, 0, 0 },
+  { 0, 0, 0, 0 }, { 0, 0, 0, 0 }, { 0, 0, 0, 0 }, { 0, 0, 0, 0 }
+ }, { /* input: linear-gray */
+  { 0, 0, 9, 0 }, { 0, 0, 9, 0 }, { 0, 0, 9, 0 }, { 0, 0, 9, 0 },
+  { 0, 0, 0, 0 }, { 0, 0, 0, 0 }, { 0, 0, 0, 0 }, { 0, 0, 0, 0 },
+  { 0, 0, 0, 0 }, { 0, 0, 0, 0 }, { 0, 0, 0, 0 }, { 0, 0, 0, 0 },
+  { 0, 0, 0, 0 }, { 0, 0, 0, 0 }, { 0, 0, 0, 0 }, { 0, 0, 0, 0 }
+ }, { /* input: linear-gray+alpha */
+  { 0, 74, 9, 0 }, { 0, 20, 9, 0 }, { 0, 74, 9, 0 }, { 0, 20, 9, 0 },
+  { 0, 0, 0, 0 }, { 0, 1, 0, 0 }, { 0, 0, 0, 0 }, { 0, 1, 0, 0 },
+  { 0, 0, 0, 0 }, { 0, 0, 0, 0 }, { 0, 0, 0, 0 }, { 0, 0, 0, 0 },
+  { 0, 0, 0, 0 }, { 0, 0, 0, 0 }, { 0, 0, 0, 0 }, { 0, 0, 0, 0 }
+ }, { /* input: linear-rgb */
+  { 0, 0, 9, 0 }, { 0, 0, 9, 0 }, { 0, 0, 9, 0 }, { 0, 0, 9, 0 },
+  { 0, 0, 4, 0 }, { 0, 0, 4, 0 }, { 0, 0, 0, 0 }, { 0, 0, 0, 0 },
+  { 0, 0, 0, 0 }, { 0, 0, 0, 0 }, { 0, 0, 0, 0 }, { 0, 0, 0, 0 },
+  { 0, 0, 0, 0 }, { 0, 0, 0, 0 }, { 0, 0, 0, 0 }, { 0, 0, 0, 0 }
+ }, { /* input: linear-rgb+alpha */
+  { 0, 126, 143, 0 }, { 0, 9, 7, 0 }, { 0, 74, 9, 0 }, { 0, 16, 9, 0 },
+  { 0, 4, 4, 0 }, { 0, 5, 4, 0 }, { 0, 0, 0, 0 }, { 0, 1, 0, 0 },
+  { 0, 0, 0, 0 }, { 0, 0, 0, 0 }, { 0, 0, 0, 0 }, { 0, 0, 0, 0 },
+  { 0, 0, 0, 0 }, { 0, 0, 0, 0 }, { 0, 0, 0, 0 }, { 0, 0, 0, 0 }
+ }, { /* input: color-mapped-sRGB-gray */
+  { 0, 0, 0, 0 }, { 0, 0, 0, 0 }, { 0, 0, 0, 0 }, { 0, 0, 0, 0 },
+  { 0, 0, 0, 0 }, { 0, 0, 0, 0 }, { 0, 0, 0, 0 }, { 0, 0, 0, 0 },
+  { 0, 0, 0, 0 }, { 0, 0, 0, 0 }, { 0, 0, 0, 0 }, { 0, 0, 0, 0 },
+  { 0, 0, 0, 0 }, { 0, 0, 0, 0 }, { 0, 0, 0, 0 }, { 0, 0, 0, 0 }
+ }, { /* input: color-mapped-sRGB-gray+alpha */
+  { 0, 0, 0, 0 }, { 0, 0, 0, 0 }, { 0, 0, 0, 0 }, { 0, 0, 0, 0 },
+  { 0, 0, 0, 0 }, { 0, 0, 0, 0 }, { 0, 0, 0, 0 }, { 0, 0, 0, 0 },
+  { 0, 0, 0, 0 }, { 0, 0, 0, 0 }, { 0, 0, 0, 0 }, { 0, 0, 0, 0 },
+  { 0, 0, 0, 0 }, { 0, 0, 0, 0 }, { 0, 0, 0, 0 }, { 0, 0, 0, 0 }
+ }, { /* input: color-mapped-sRGB-rgb */
+  { 0, 0, 13, 0 }, { 0, 0, 13, 0 }, { 0, 0, 8, 0 }, { 0, 0, 8, 0 },
+  { 0, 0, 673, 0 }, { 0, 0, 673, 0 }, { 0, 0, 674, 0 }, { 0, 0, 674, 0 },
+  { 0, 0, 1, 0 }, { 0, 0, 1, 0 }, { 0, 0, 0, 0 }, { 0, 0, 0, 0 },
+  { 0, 0, 460, 0 }, { 0, 0, 460, 0 }, { 0, 0, 263, 0 }, { 0, 0, 263, 0 }
+ }, { /* input: color-mapped-sRGB-rgb+alpha */
+  { 0, 6, 8, 0 }, { 0, 7, 8, 0 }, { 0, 75, 8, 0 }, { 0, 9, 8, 0 },
+  { 0, 585, 427, 0 }, { 0, 585, 427, 0 }, { 0, 717, 409, 0 }, { 0, 717, 409, 0 },
+  { 0, 1, 1, 0 }, { 0, 1, 1, 0 }, { 0, 1, 0, 0 }, { 0, 0, 0, 0 },
+  { 0, 13323, 460, 0 }, { 0, 334, 460, 0 }, { 0, 16480, 263, 0 }, { 0, 243, 263, 0 }
+ }, { /* input: color-mapped-linear-gray */
+  { 0, 0, 0, 0 }, { 0, 0, 0, 0 }, { 0, 0, 0, 0 }, { 0, 0, 0, 0 },
+  { 0, 0, 0, 0 }, { 0, 0, 0, 0 }, { 0, 0, 0, 0 }, { 0, 0, 0, 0 },
+  { 0, 0, 0, 0 }, { 0, 0, 0, 0 }, { 0, 0, 0, 0 }, { 0, 0, 0, 0 },
+  { 0, 0, 282, 0 }, { 0, 0, 0, 0 }, { 0, 0, 0, 0 }, { 0, 0, 0, 0 }
+ }, { /* input: color-mapped-linear-gray+alpha */
+  { 0, 0, 0, 0 }, { 0, 0, 0, 0 }, { 0, 0, 0, 0 }, { 0, 0, 0, 0 },
+  { 0, 0, 0, 0 }, { 0, 0, 0, 0 }, { 0, 0, 0, 0 }, { 0, 0, 0, 0 },
+  { 0, 0, 0, 0 }, { 0, 0, 0, 0 }, { 0, 0, 0, 0 }, { 0, 0, 0, 0 },
+  { 0, 0, 0, 0 }, { 0, 253, 282, 0 }, { 0, 0, 0, 0 }, { 0, 0, 0, 0 }
+ }, { /* input: color-mapped-linear-rgb */
+  { 0, 0, 0, 0 }, { 0, 0, 0, 0 }, { 0, 0, 0, 0 }, { 0, 0, 0, 0 },
+  { 0, 0, 0, 0 }, { 0, 0, 0, 0 }, { 0, 0, 0, 0 }, { 0, 0, 0, 0 },
+  { 0, 0, 0, 0 }, { 0, 0, 0, 0 }, { 0, 0, 0, 0 }, { 0, 0, 0, 0 },
+  { 0, 0, 0, 0 }, { 0, 0, 0, 0 }, { 0, 0, 265, 0 }, { 0, 0, 0, 0 }
+ }, { /* input: color-mapped-linear-rgb+alpha */
+  { 0, 0, 0, 0 }, { 0, 0, 0, 0 }, { 0, 0, 0, 0 }, { 0, 0, 0, 0 },
+  { 0, 0, 0, 0 }, { 0, 0, 0, 0 }, { 0, 0, 0, 0 }, { 0, 0, 0, 0 },
+  { 0, 0, 0, 0 }, { 0, 0, 0, 0 }, { 0, 0, 0, 0 }, { 0, 0, 0, 0 },
+  { 0, 0, 0, 0 }, { 0, 0, 0, 0 }, { 0, 0, 0, 0 }, { 0, 243, 265, 0 }
+ }
+};
+static png_uint_16 gpc_error_via_linear[16][4/*out*/][4] =
+{
+ { /* input: sRGB-gray */
+  { 0, 0, 7, 0 }, { 0, 0, 7, 0 }, { 0, 0, 7, 0 }, { 0, 0, 7, 0 }
+ }, { /* input: sRGB-gray+alpha */
+  { 0, 15, 15, 0 }, { 0, 186, 15, 0 }, { 0, 15, 15, 0 }, { 0, 186, 15, 0 }
+ }, { /* input: sRGB-rgb */
+  { 0, 0, 19, 0 }, { 0, 0, 19, 0 }, { 0, 0, 15, 0 }, { 0, 0, 15, 0 }
+ }, { /* input: sRGB-rgb+alpha */
+  { 0, 12, 14, 0 }, { 0, 180, 14, 0 }, { 0, 14, 15, 0 }, { 0, 186, 15, 0 }
+ }, { /* input: linear-gray */
+  { 0, 0, 1, 0 }, { 0, 0, 1, 0 }, { 0, 0, 1, 0 }, { 0, 0, 1, 0 }
+ }, { /* input: linear-gray+alpha */
+  { 0, 1, 1, 0 }, { 0, 1, 1, 0 }, { 0, 1, 1, 0 }, { 0, 1, 1, 0 }
+ }, { /* input: linear-rgb */
+  { 0, 0, 1, 0 }, { 0, 0, 1, 0 }, { 0, 0, 1, 0 }, { 0, 0, 1, 0 }
+ }, { /* input: linear-rgb+alpha */
+  { 0, 1, 1, 0 }, { 0, 8, 1, 0 }, { 0, 1, 1, 0 }, { 0, 1, 1, 0 }
+ }, { /* input: color-mapped-sRGB-gray */
+  { 0, 0, 0, 0 }, { 0, 0, 0, 0 }, { 0, 0, 0, 0 }, { 0, 0, 0, 0 }
+ }, { /* input: color-mapped-sRGB-gray+alpha */
+  { 0, 0, 0, 0 }, { 0, 0, 0, 0 }, { 0, 0, 0, 0 }, { 0, 0, 0, 0 }
+ }, { /* input: color-mapped-sRGB-rgb */
+  { 0, 0, 13, 0 }, { 0, 0, 13, 0 }, { 0, 0, 14, 0 }, { 0, 0, 14, 0 }
+ }, { /* input: color-mapped-sRGB-rgb+alpha */
+  { 0, 4, 8, 0 }, { 0, 9, 8, 0 }, { 0, 8, 3, 0 }, { 0, 32, 3, 0 }
+ }, { /* input: color-mapped-linear-gray */
+  { 0, 0, 0, 0 }, { 0, 0, 0, 0 }, { 0, 0, 0, 0 }, { 0, 0, 0, 0 }
+ }, { /* input: color-mapped-linear-gray+alpha */
+  { 0, 0, 0, 0 }, { 0, 0, 0, 0 }, { 0, 0, 0, 0 }, { 0, 0, 0, 0 }
+ }, { /* input: color-mapped-linear-rgb */
+  { 0, 0, 0, 0 }, { 0, 0, 0, 0 }, { 0, 0, 0, 0 }, { 0, 0, 0, 0 }
+ }, { /* input: color-mapped-linear-rgb+alpha */
+  { 0, 0, 0, 0 }, { 0, 0, 0, 0 }, { 0, 0, 0, 0 }, { 0, 0, 0, 0 }
+ }
+};
+static png_uint_16 gpc_error_to_colormap[8/*i*/][8/*o*/][4] =
+{
+ { /* input: sRGB-gray */
+  { 0, 0, 9, 0 }, { 0, 0, 9, 0 }, { 0, 0, 9, 0 }, { 0, 0, 9, 0 },
+  { 0, 0, 560, 0 }, { 0, 0, 560, 0 }, { 0, 0, 560, 0 }, { 0, 0, 560, 0 }
+ }, { /* input: sRGB-gray+alpha */
+  { 0, 19, 2, 0 }, { 0, 255, 2, 25 }, { 0, 88, 2, 0 }, { 0, 255, 2, 25 },
+  { 0, 1012, 745, 0 }, { 0, 16026, 745, 6425 }, { 0, 1012, 745, 0 }, { 0, 16026, 745, 6425 }
+ }, { /* input: sRGB-rgb */
+  { 0, 0, 19, 0 }, { 0, 0, 19, 0 }, { 0, 0, 25, 0 }, { 0, 0, 25, 0 },
+  { 0, 0, 937, 0 }, { 0, 0, 937, 0 }, { 0, 0, 13677, 0 }, { 0, 0, 13677, 0 }
+ }, { /* input: sRGB-rgb+alpha */
+  { 0, 63, 77, 0 }, { 0, 255, 19, 25 }, { 0, 220, 25, 0 }, { 0, 255, 25, 67 },
+  { 0, 17534, 18491, 0 }, { 0, 15614, 2824, 6425 }, { 0, 14019, 13677, 0 }, { 0, 48573, 13677, 17219 }
+ }, { /* input: linear-gray */
+  { 0, 0, 73, 0 }, { 0, 0, 73, 0 }, { 0, 0, 73, 0 }, { 0, 0, 73, 0 },
+  { 0, 0, 18817, 0 }, { 0, 0, 18817, 0 }, { 0, 0, 18817, 0 }, { 0, 0, 18817, 0 }
+ }, { /* input: linear-gray+alpha */
+  { 0, 74, 74, 0 }, { 0, 255, 74, 25 }, { 0, 97, 74, 0 }, { 0, 255, 74, 25 },
+  { 0, 18919, 18907, 0 }, { 0, 24549, 18907, 6552 }, { 0, 18919, 18907, 0 }, { 0, 24549, 18907, 6552 }
+ }, { /* input: linear-rgb */
+  { 0, 0, 73, 0 }, { 0, 0, 73, 0 }, { 0, 0, 98, 0 }, { 0, 0, 98, 0 },
+  { 0, 0, 18664, 0 }, { 0, 0, 18664, 0 }, { 0, 0, 24998, 0 }, { 0, 0, 24998, 0 }
+ }, { /* input: linear-rgb+alpha */
+  { 0, 181, 196, 0 }, { 0, 255, 61, 25 }, { 206, 187, 98, 0 }, { 0, 255, 98, 67 },
+  { 0, 18141, 18137, 0 }, { 0, 17494, 17504, 6553 }, { 0, 24979, 24992, 0 }, { 0, 46509, 24992, 17347 }
+ }
+};
+/* END MACHINE GENERATED */
 #endif /* COLORMAP flag check */
 #endif /* flag checks */

@@ -2038,7 +2154,7 @@ typedef struct
   int          in_opaque;   /* Value of input alpha that is opaque */
   int          is_palette;  /* Sample values come from the palette */
   int          accumulate;  /* Accumlate component errors (don't log) */
-   int          output_8bit; /* Output is 8-bit (else 16-bit) */
+   int          output_8bit; /* Output is 8 bit (else 16 bit) */

   void (*in_gp)(Pixel*, png_const_voidp);
   void (*out_gp)(Pixel*, png_const_voidp);
@@ -3041,14 +3157,14 @@ read_file(Image *image, png_uint_32 format, png_const_colorp background)
 static int
 read_one_file(Image *image)
 {
-   if (!(image->opts & USE_FILE) || (image->opts & USE_STDIO))
+   if (!(image->opts & READ_FILE) || (image->opts & USE_STDIO))
   {
      /* memory or stdio. */
      FILE *f = fopen(image->file_name, "rb");

      if (f != NULL)
      {
-         if (image->opts & USE_FILE)
+         if (image->opts & READ_FILE)
            image->input_file = f;

         else /* memory */
@@ -3129,8 +3245,7 @@ write_one_file(Image *output, Image *image, int convert_to_8bit)

   if (image->opts & USE_STDIO)
   {
-#ifdef PNG_SIMPLIFIED_WRITE_STDIO_SUPPORTED
-#ifndef __COVERITY__
+#ifndef PNG_USE_MKSTEMP
      FILE *f = tmpfile();
 #else
      /* Experimental. Coverity says tmpfile() is insecure because it
@@ -3164,7 +3279,7 @@ write_one_file(Image *output, Image *image, int convert_to_8bit)
        (void) unlink(tmpfile);
      }
 #endif
-
+      
      if (f != NULL)
      {
         if (png_image_write_to_stdio(&image->image, f, convert_to_8bit,
@@ -3192,14 +3307,10 @@ write_one_file(Image *output, Image *image, int convert_to_8bit)

      else
         return logerror(image, "tmpfile", ": open: ", strerror(errno));
-#else /* SIMPLIFIED_WRITE_STDIO */
-      return logerror(image, "tmpfile", ": open: unsupported", "");
-#endif /* SIMPLIFIED_WRITE_STDIO */
   }

-   else if (image->opts & USE_FILE)
+   else
   {
-#ifdef PNG_SIMPLIFIED_WRITE_STDIO_SUPPORTED
      static int counter = 0;
      char name[32];

@@ -3219,51 +3330,6 @@ write_one_file(Image *output, Image *image, int convert_to_8bit)

      else
         return logerror(image, name, ": write failed", "");
-#else /* SIMPLIFIED_WRITE_STDIO */
-      return logerror(image, "stdio", ": open: unsupported", "");
-#endif /* SIMPLIFIED_WRITE_STDIO */
-   }
-
-   else /* use memory */
-   {
-      png_alloc_size_t size;
-
-      if (png_image_write_get_memory_size(image->image, size, convert_to_8bit,
-               image->buffer+16, (png_int_32)image->stride, image->colormap))
-      {
-         /* This is non-fatal but ignoring it was causing serious problems in
-          * the macro to be ignored:
-          */
-         if (size > PNG_IMAGE_PNG_SIZE_MAX(image->image))
-            return logerror(image, "memory", ": PNG_IMAGE_SIZE_MAX wrong", "");
-
-         initimage(output, image->opts, "memory", image->stride_extra);
-         output->input_memory = malloc(size);
-
-         if (output->input_memory != NULL)
-         {
-            output->input_memory_size = size;
-
-            if (png_image_write_to_memory(&image->image, output->input_memory,
-                  &output->input_memory_size, convert_to_8bit, image->buffer+16,
-                  (png_int_32)image->stride, image->colormap))
-            {
-               /* This is also non-fatal but it safes safer to error out anyway:
-                */
-               if (size != output->input_memory_size)
-                  return logerror(image, "memory", ": memory size wrong", "");
-            }
-
-            else
-               return logerror(image, "memory", ": write failed", "");
-         }
-
-         else
-            return logerror(image, "memory", ": out of memory", "");
-      }
-
-      else
-         return logerror(image, "memory", ": get size:", "");
   }

   /* 'output' has an initialized temporary image, read this back in and compare
@@ -3439,8 +3505,6 @@ test_one_file(const char *file_name, format_list *formats, png_uint_32 opts,
   int result;
   Image image;

-   if (!(opts & NO_RESEED))
-      reseed(); /* ensure that the random numbers don't depend on file order */
   newimage(&image);
   initimage(&image, opts, file_name, stride_extra);
   result = read_one_file(&image);
@@ -3478,7 +3542,7 @@ test_one_file(const char *file_name, format_list *formats, png_uint_32 opts,
 int
 main(int argc, char **argv)
 {
-   png_uint_32 opts = FAST_WRITE | STRICT;
+   png_uint_32 opts = FAST_WRITE;
   format_list formats;
   const char *touch = NULL;
   int log_pass = 0;
@@ -3487,17 +3551,11 @@ main(int argc, char **argv)
   int retval = 0;
   int c;

-#if PNG_LIBPNG_VER >= 10700
-      /* This error should not exist in 1.7 or later: */
-      opts |= GBG_ERROR;
-#endif
-
   init_sRGB_to_d();
 #if 0
   init_error_via_linear();
 #endif
   format_init(&formats);
-   reseed(); /* initialize random number seeds */

   for (c=1; c<argc; ++c)
   {
@@ -3512,17 +3570,17 @@ main(int argc, char **argv)
      }
      else if (strcmp(arg, "--file") == 0)
 #        ifdef PNG_STDIO_SUPPORTED
-            opts |= USE_FILE;
+            opts |= READ_FILE;
 #        else
-            return SKIP; /* skipped: no support */
+            return 77; /* skipped: no support */
 #        endif
      else if (strcmp(arg, "--memory") == 0)
-         opts &= ~USE_FILE;
+         opts &= ~READ_FILE;
      else if (strcmp(arg, "--stdio") == 0)
 #        ifdef PNG_STDIO_SUPPORTED
            opts |= USE_STDIO;
 #        else
-            return SKIP; /* skipped: no support */
+            return 77; /* skipped: no support */
 #        endif
      else if (strcmp(arg, "--name") == 0)
         opts &= ~USE_STDIO;
@@ -3548,16 +3606,10 @@ main(int argc, char **argv)
         opts &= ~KEEP_GOING;
      else if (strcmp(arg, "--strict") == 0)
         opts |= STRICT;
-      else if (strcmp(arg, "--nostrict") == 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, "--noreseed") == 0)
-         opts |= NO_RESEED;
-      else if (strcmp(arg, "--fault-gbg-warning") == 0)
-         opts |= GBG_ERROR;
      else if (strcmp(arg, "--tmpfile") == 0)
      {
         if (c+1 < argc)
@@ -3670,23 +3722,6 @@ main(int argc, char **argv)
   {
      unsigned int in;

-      printf("/* contrib/libtests/pngstest-errors.h\n");
-      printf(" *\n");
-      printf(" * BUILT USING:" PNG_HEADER_VERSION_STRING);
-      printf(" *\n");
-      printf(" * This code is released under the libpng license.\n");
-      printf(" * For conditions of distribution and use, see the disclaimer\n");
-      printf(" * and license in png.h\n");
-      printf(" *\n");
-      printf(" * THIS IS A MACHINE GENERATED FILE: do not edit it directly!\n");
-      printf(" * Instead run:\n");
-      printf(" *\n");
-      printf(" *    pngstest --accumulate\n");
-      printf(" *\n");
-      printf(" * on as many PNG files as possible; at least PNGSuite and\n");
-      printf(" * contrib/libtests/testpngs.\n");
-      printf(" */\n");
-
      printf("static png_uint_16 gpc_error[16/*in*/][16/*out*/][4/*a*/] =\n");
      printf("{\n");
      for (in=0; in<16; ++in)
@@ -3776,7 +3811,6 @@ main(int argc, char **argv)
            putchar('\n');
      }
      printf("};\n");
-      printf("/* END MACHINE GENERATED */\n");
   }

   if (retval == 0 && touch != NULL)
@@ -3814,6 +3848,6 @@ int main(void)
 {
   fprintf(stderr, "pngstest: no read support in libpng, test skipped\n");
   /* So the test is skipped: */
-   return SKIP;
+   return 77;
 }
 #endif /* PNG_SIMPLIFIED_READ_SUPPORTED */
--- a/contrib/libtests/pngunknown.c
+++ b/contrib/libtests/pngunknown.c
@@ -1,8 +1,8 @@

 /* pngunknown.c - test the read side unknown chunk handling
 *
- * Last changed in libpng 1.6.22 [May 26, 2016]
- * Copyright (c) 2015,2016 Glenn Randers-Pehrson
+ * Last changed in libpng 1.6.10 [March 6, 2014]
+ * Copyright (c) 2014 Glenn Randers-Pehrson
 * Written by John Cunningham Bowler
 *
 * This code is released under the libpng license.
@@ -30,21 +30,10 @@
 #  include "../../png.h"
 #endif

-/* 1.6.1 added support for the configure test harness, which uses 77 to indicate
- * a skipped test, in earlier versions we need to succeed on a skipped test, so:
- */
-#if PNG_LIBPNG_VER >= 10601 && defined(HAVE_CONFIG_H)
-#  define SKIP 77
-#else
-#  define SKIP 0
-#endif
-
-
 /* Since this program tests the ability to change the unknown chunk handling
 * these must be defined:
 */
 #if defined(PNG_SET_UNKNOWN_CHUNKS_SUPPORTED) &&\
-   defined(PNG_STDIO_SUPPORTED) &&\
   defined(PNG_READ_SUPPORTED)

 /* One of these must be defined to allow us to find out what happened.  It is
@@ -374,7 +363,7 @@ ancillary(const char *name)
   return PNG_CHUNK_ANCILLARY(PNG_U32(name[0], name[1], name[2], name[3]));
 }

-#ifdef PNG_SAVE_UNKNOWN_CHUNKS_SUPPORTED
+#ifdef PNG_STORE_UNKNOWN_CHUNKS_SUPPORTED
 static int
 ancillaryb(const png_byte *name)
 {
@@ -565,7 +554,7 @@ read_callback(png_structp pp, png_unknown_chunkp pc)
   /* However if there is no support to store unknown chunks don't ask libpng to
    * do it; there will be an png_error.
    */
-#  ifdef PNG_SAVE_UNKNOWN_CHUNKS_SUPPORTED
+#  ifdef PNG_STORE_UNKNOWN_CHUNKS_SUPPORTED
      return discard;
 #  else
      return 1; /*handled; discard*/
@@ -573,7 +562,7 @@ read_callback(png_structp pp, png_unknown_chunkp pc)
 }
 #endif /* READ_USER_CHUNKS_SUPPORTED */

-#ifdef PNG_SAVE_UNKNOWN_CHUNKS_SUPPORTED
+#ifdef PNG_STORE_UNKNOWN_CHUNKS_SUPPORTED
 static png_uint_32
 get_unknown(display *d, png_infop info_ptr, int after_IDAT)
 {
@@ -626,7 +615,7 @@ get_unknown(display *d, png_infop info_ptr, int after_IDAT)

   return flags;
 }
-#else /* SAVE_UNKNOWN_CHUNKS */
+#else
 static png_uint_32
 get_unknown(display *d, png_infop info_ptr, int after_IDAT)
   /* Otherwise this will return the cached values set by any user callback */
@@ -645,8 +634,8 @@ get_unknown(display *d, png_infop info_ptr, int after_IDAT)
       * a check to ensure the logic is correct.
       */
 #     error No store support and no user chunk support, this will not work
-#  endif /* READ_USER_CHUNKS */
-#endif /* SAVE_UNKNOWN_CHUNKS */
+#  endif
+#endif

 static int
 check(FILE *fp, int argc, const char **argv, png_uint_32p flags/*out*/,
@@ -733,17 +722,11 @@ check(FILE *fp, int argc, const char **argv, png_uint_32p flags/*out*/,
                   * in this case, so we just check the arguments!  This could
                   * be improved in the future by using the read callback.
                   */
-#                 if PNG_LIBPNG_VER >= 10700 &&\
-                     !defined(PNG_SAVE_UNKNOWN_CHUNKS_SUPPORTED)
-                     if (option < PNG_HANDLE_CHUNK_IF_SAFE)
-#                 endif /* 1.7+ SAVE_UNKNOWN_CHUNKS */
-                  {
-                     png_byte name[5];
+                  png_byte name[5];

-                     memcpy(name, chunk_info[chunk].name, 5);
-                     png_set_keep_unknown_chunks(d->png_ptr, option, name, 1);
-                     chunk_info[chunk].keep = option;
-                  }
+                  memcpy(name, chunk_info[chunk].name, 5);
+                  png_set_keep_unknown_chunks(d->png_ptr, option, name, 1);
+                  chunk_info[chunk].keep = option;
                  continue;
               }

@@ -752,12 +735,7 @@ check(FILE *fp, int argc, const char **argv, png_uint_32p flags/*out*/,
            case 7: /* default */
               if (memcmp(argv[i], "default", 7) == 0)
               {
-#                 if PNG_LIBPNG_VER >= 10700 &&\
-                     !defined(PNG_SAVE_UNKNOWN_CHUNKS_SUPPORTED)
-                     if (option < PNG_HANDLE_CHUNK_IF_SAFE)
-#                 endif /* 1.7+ SAVE_UNKNOWN_CHUNKS */
-                     png_set_keep_unknown_chunks(d->png_ptr, option, NULL, 0);
-
+                  png_set_keep_unknown_chunks(d->png_ptr, option, NULL, 0);
                  d->keep = option;
                  continue;
               }
@@ -767,12 +745,7 @@ check(FILE *fp, int argc, const char **argv, png_uint_32p flags/*out*/,
            case 3: /* all */
               if (memcmp(argv[i], "all", 3) == 0)
               {
-#                 if PNG_LIBPNG_VER >= 10700 &&\
-                     !defined(PNG_SAVE_UNKNOWN_CHUNKS_SUPPORTED)
-                     if (option < PNG_HANDLE_CHUNK_IF_SAFE)
-#                 endif /* 1.7+ SAVE_UNKNOWN_CHUNKS */
-                     png_set_keep_unknown_chunks(d->png_ptr, option, NULL, -1);
-
+                  png_set_keep_unknown_chunks(d->png_ptr, option, NULL, -1);
                  d->keep = option;

                  for (chunk = 0; chunk < NINFO; ++chunk)
@@ -1012,20 +985,6 @@ perform_one_test(FILE *fp, int argc, const char **argv,

   def = check(fp, argc, argv, flags[1], d, set_callback);

-   /* If IDAT is being handled as unknown the image read is skipped and all the
-    * IDATs after the first end up in the end info struct, so in this case add
-    * IDAT to the list of unknowns.  (Do this after 'check' above sets the
-    * chunk_info 'keep' fields.)
-    *
-    * Note that the flag setting has to be in the 'known' field to avoid
-    * triggering the consistency check below and the flag must only be set if
-    * there are multiple IDATs, so if the check above did find an unknown IDAT
-    * after IDAT.
-    */
-   if (chunk_info[0/*IDAT*/].keep != PNG_HANDLE_CHUNK_AS_DEFAULT &&
-       (flags[1][3] & PNG_INFO_IDAT) != 0)
-      flags[0][2] |= PNG_INFO_IDAT;
-
   /* Chunks should either be known or unknown, never both and this should apply
    * whether the chunk is before or after the IDAT (actually, the app can
    * probably change this by swapping the handling after the image, but this
@@ -1270,7 +1229,7 @@ main(void)
   fprintf(stderr,
      " test ignored: no support to find out about unknown chunks\n");
   /* So the test is skipped: */
-   return SKIP;
+   return 77;
 }
 #endif /* READ_USER_CHUNKS || SAVE_UNKNOWN_CHUNKS */

@@ -1281,6 +1240,6 @@ main(void)
   fprintf(stderr,
      " test ignored: no support to modify unknown chunk handling\n");
   /* So the test is skipped: */
-   return SKIP;
+   return 77;
 }
-#endif /* SET_UNKNOWN_CHUNKS && READ*/
+#endif /* SET_UNKNOWN_CHUNKS && READ */
--- a/contrib/libtests/pngvalid.c
+++ b/contrib/libtests/pngvalid.c
--- a/contrib/libtests/readpng.c
+++ b/contrib/libtests/readpng.c
@@ -62,7 +62,6 @@ read_png(FILE *fp)
   {
      png_size_t rowbytes = png_get_rowbytes(png_ptr, info_ptr);

-      /* Failure to initialize these is harmless */
      row = malloc(rowbytes);
      display = malloc(rowbytes);

@@ -71,12 +70,7 @@ read_png(FILE *fp)

      {
         png_uint_32 height = png_get_image_height(png_ptr, info_ptr);
-#        ifdef PNG_READ_INTERLACING_SUPPORTED
-            int passes = png_set_interlace_handling(png_ptr);
-#        else /* !READ_INTERLACING */
-            int passes = png_get_interlace_type(png_ptr, info_ptr) ==
-               PNG_INTERLACE_ADAM7 ? PNG_INTERLACE_ADAM7_PASSES : 1;
-#        endif /* !READ_INTERLACING */
+         int passes = png_set_interlace_handling(png_ptr);
         int pass;

         png_start_read_image(png_ptr);
@@ -85,11 +79,6 @@ read_png(FILE *fp)
         {
            png_uint_32 y = height;

-#           ifndef PNG_READ_INTERLACING_SUPPORTED
-               if (passes == PNG_INTERLACE_ADAM7_PASSES)
-                  y = PNG_PASS_ROWS(y, pass);
-#           endif /* READ_INTERLACING */
-
            /* NOTE: this trashes the row each time; interlace handling won't
             * work, but this avoids memory thrashing for speed testing.
             */
--- a/contrib/libtests/tarith.c
+++ b/contrib/libtests/tarith.c
@@ -634,7 +634,7 @@ int validation_muldiv(int count, int argc, char **argv)
   {
      png_fixed_point result;
      /* NOTE: your mileage may vary, a type is required below that can
-       * hold 64 bits or more, if floating point is used a 64-bit or
+       * hold 64 bits or more, if floating point is used a 64 bit or
       * better mantissa is required.
       */
      long long int fp, fpround;
@@ -721,7 +721,7 @@ int validation_muldiv(int count, int argc, char **argv)
   }
   while (--count > 0);

-   printf("%d tests including %d overflows, %d passed, %d failed (%d 64-bit "
+   printf("%d tests including %d overflows, %d passed, %d failed (%d 64 bit "
      "errors)\n", tested, overflow, passed, error, error64);
   return 0;
 }
@@ -799,13 +799,13 @@ int validation_gamma(int argc, char **argv)
         if (i == 0 && png_log8bit(i) != 0xffffffff ||
             i != 0 && png_log8bit(i) != floor(correct+.5))
         {
-            fprintf(stderr, "8-bit log error: %d: got %u, expected %f\n",
+            fprintf(stderr, "8 bit log error: %d: got %u, expected %f\n",
               i, png_log8bit(i), correct);
         }
      }

      if (!silent)
-         printf("maximum 8-bit log error = %f\n", maxerr);
+         printf("maximum 8 bit log error = %f\n", maxerr);

      maxerr = 0;
      for (i=0; i<65536; ++i)
@@ -821,14 +821,14 @@ int validation_gamma(int argc, char **argv)
         {
            if (error > .68) /* By experiment error is less than .68 */
            {
-               fprintf(stderr, "16-bit log error: %d: got %u, expected %f"
+               fprintf(stderr, "16 bit log error: %d: got %u, expected %f"
                  " error: %f\n", i, png_log16bit(i), correct, error);
            }
         }
      }

      if (!silent)
-         printf("maximum 16-bit log error = %f\n", maxerr);
+         printf("maximum 16 bit log error = %f\n", maxerr);

      /* Now exponentiations. */
      maxerr = 0;
@@ -841,13 +841,13 @@ int validation_gamma(int argc, char **argv)
            maxerr = fabs(error);
         if (fabs(error) > 1883) /* By experiment. */
         {
-            fprintf(stderr, "32-bit exp error: %d: got %u, expected %f"
+            fprintf(stderr, "32 bit exp error: %d: got %u, expected %f"
                  " error: %f\n", i, png_exp(i), correct, error);
         }
      }

      if (!silent)
-         printf("maximum 32-bit exp error = %f\n", maxerr);
+         printf("maximum 32 bit exp error = %f\n", maxerr);

      maxerr = 0;
      for (i=0; i<=0xfffff; ++i)
@@ -859,13 +859,13 @@ int validation_gamma(int argc, char **argv)
            maxerr = fabs(error);
         if (fabs(error) > .50002) /* By experiment */
         {
-            fprintf(stderr, "8-bit exp error: %d: got %u, expected %f"
+            fprintf(stderr, "8 bit exp error: %d: got %u, expected %f"
                  " error: %f\n", i, png_exp8bit(i), correct, error);
         }
      }

      if (!silent)
-         printf("maximum 8-bit exp error = %f\n", maxerr);
+         printf("maximum 8 bit exp error = %f\n", maxerr);

      maxerr = 0;
      for (i=0; i<=0xfffff; ++i)
@@ -877,13 +877,13 @@ int validation_gamma(int argc, char **argv)
            maxerr = fabs(error);
         if (fabs(error) > .524) /* By experiment */
         {
-            fprintf(stderr, "16-bit exp error: %d: got %u, expected %f"
+            fprintf(stderr, "16 bit exp error: %d: got %u, expected %f"
                  " error: %f\n", i, png_exp16bit(i), correct, error);
         }
      }

      if (!silent)
-         printf("maximum 16-bit exp error = %f\n", maxerr);
+         printf("maximum 16 bit exp error = %f\n", maxerr);
   } /* !onlygamma */

   /* Test the overall gamma correction. */
@@ -913,7 +913,7 @@ int validation_gamma(int argc, char **argv)
      }

      if (!silent)
-         printf("gamma %f: maximum 8-bit error %f\n", g, maxerr);
+         printf("gamma %f: maximum 8 bit error %f\n", g, maxerr);

      maxerr = 0;
      for (j=0; j<65536; ++j)
@@ -932,7 +932,7 @@ int validation_gamma(int argc, char **argv)
      }

      if (!silent)
-         printf("gamma %f: maximum 16-bit error %f\n", g, maxerr);
+         printf("gamma %f: maximum 16 bit error %f\n", g, maxerr);
   }

   return 0;
--- a/contrib/libtests/timepng.c
+++ b/contrib/libtests/timepng.c
@@ -1,8 +1,8 @@
 /* timepng.c
 *
- * Copyright (c) 2013,2016 John Cunningham Bowler
+ * Copyright (c) 2013 John Cunningham Bowler
 *
- * Last changed in libpng 1.6.22 [May 26, 2016]
+ * 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
@@ -10,17 +10,15 @@
 *
 * Load an arbitrary number of PNG files (from the command line, or, if there
 * are no arguments on the command line, from stdin) then run a time test by
- * reading each file by row or by image (possibly with transforms in the latter
- * case).  The only output is a time as a floating point number of seconds with
- * 9 decimal digits.
+ * reading each file by row.  The test does nothing with the read result and
+ * does no transforms.  The only output is a time as a floating point number of
+ * seconds with 9 decimal digits.
 */
 #define _POSIX_C_SOURCE 199309L /* for clock_gettime */

 #include <stdlib.h>
 #include <stdio.h>
 #include <string.h>
-#include <errno.h>
-#include <limits.h>

 #include <time.h>

@@ -37,73 +35,36 @@
 #  include "../../png.h"
 #endif

-/* The following is to support direct compilation of this file as C++ */
-#ifdef __cplusplus
-#  define voidcast(type, value) static_cast<type>(value)
-#else
-#  define voidcast(type, value) (value)
-#endif /* __cplusplus */
-
-/* 'CLOCK_PROCESS_CPUTIME_ID' is one of the clock timers for clock_gettime.  It
- * need not be supported even when clock_gettime is available.  It returns the
- * 'CPU' time the process has consumed.  'CPU' time is assumed to include time
- * when the CPU is actually blocked by a pending cache fill but not time
- * waiting for page faults.  The attempt is to get a measure of the actual time
- * the implementation takes to read a PNG ignoring the potentially very large IO
- * overhead.
- */
-#if defined (CLOCK_PROCESS_CPUTIME_ID) && defined(PNG_STDIO_SUPPORTED) &&\
-    defined(PNG_EASY_ACCESS_SUPPORTED) &&\
-    (PNG_LIBPNG_VER >= 10700 ? defined(PNG_READ_PNG_SUPPORTED) :\
-     defined (PNG_SEQUENTIAL_READ_SUPPORTED) &&\
-     defined(PNG_INFO_IMAGE_SUPPORTED))
-
-typedef struct
+static int read_png(FILE *fp)
 {
-   FILE *input;
-   FILE *output;
-}  io_data;
-
-static PNG_CALLBACK(void, read_and_copy,
-      (png_structp png_ptr, png_bytep buffer, png_size_t cb))
-{
-   io_data *io = (io_data*)png_get_io_ptr(png_ptr);
-
-   if (fread(buffer, cb, 1, io->input) != 1)
-      png_error(png_ptr, strerror(errno));
-
-   if (fwrite(buffer, cb, 1, io->output) != 1)
-   {
-      perror("temporary file");
-      fprintf(stderr, "temporary file PNG write failed\n");
-      exit(1);
-   }
-}
-
-static void read_by_row(png_structp png_ptr, png_infop info_ptr,
-      FILE *write_ptr, FILE *read_ptr)
-{
-   /* These don't get freed on error, this is fine; the program immediately
-    * exits.
-    */
+   png_structp png_ptr = png_create_read_struct(PNG_LIBPNG_VER_STRING,0,0,0);
+   png_infop info_ptr = NULL;
   png_bytep row = NULL, display = NULL;
-   io_data io_copy;

-   if (write_ptr != NULL)
+   if (png_ptr == NULL)
+      return 0;
+
+   if (setjmp(png_jmpbuf(png_ptr)))
   {
-      /* Set up for a copy to the temporary file: */
-      io_copy.input = read_ptr;
-      io_copy.output = write_ptr;
-      png_set_read_fn(png_ptr, &io_copy, read_and_copy);
+      png_destroy_read_struct(&png_ptr, &info_ptr, NULL);
+      if (row != NULL) free(row);
+      if (display != NULL) free(display);
+      return 0;
   }

+   png_init_io(png_ptr, fp);
+
+   info_ptr = png_create_info_struct(png_ptr);
+   if (info_ptr == NULL)
+      png_error(png_ptr, "OOM allocating info structure");
+
   png_read_info(png_ptr, info_ptr);

   {
      png_size_t rowbytes = png_get_rowbytes(png_ptr, info_ptr);

-      row = voidcast(png_bytep,malloc(rowbytes));
-      display = voidcast(png_bytep,malloc(rowbytes));
+      row = malloc(rowbytes);
+      display = malloc(rowbytes);

      if (row == NULL || display == NULL)
         png_error(png_ptr, "OOM allocating row buffers");
@@ -120,8 +81,7 @@ static void read_by_row(png_structp png_ptr, png_infop info_ptr,
            png_uint_32 y = height;

            /* NOTE: this trashes the row each time; interlace handling won't
-             * work, but this avoids memory thrashing for speed testing and is
-             * somewhat representative of an application that works row-by-row.
+             * work, but this avoids memory thrashing for speed testing.
             */
            while (y-- > 0)
               png_read_row(png_ptr, row, display);
@@ -131,51 +91,9 @@ static void read_by_row(png_structp png_ptr, png_infop info_ptr,

   /* Make sure to read to the end of the file: */
   png_read_end(png_ptr, info_ptr);
-
-   /* Free this up: */
+   png_destroy_read_struct(&png_ptr, &info_ptr, NULL);
   free(row);
   free(display);
-}
-
-static PNG_CALLBACK(void, no_warnings, (png_structp png_ptr,
-         png_const_charp warning))
-{
-   (void)png_ptr;
-   (void)warning;
-}
-
-static int read_png(FILE *fp, png_int_32 transforms, FILE *write_file)
-{
-   png_structp png_ptr = png_create_read_struct(PNG_LIBPNG_VER_STRING,0,0,
-         no_warnings);
-   png_infop info_ptr = NULL;
-
-   if (png_ptr == NULL)
-      return 0;
-
-   if (setjmp(png_jmpbuf(png_ptr)))
-   {
-      png_destroy_read_struct(&png_ptr, &info_ptr, NULL);
-      return 0;
-   }
-
-#  ifdef PNG_BENIGN_ERRORS_SUPPORTED
-      png_set_benign_errors(png_ptr, 1/*allowed*/);
-#  endif
-   png_init_io(png_ptr, fp);
-
-   info_ptr = png_create_info_struct(png_ptr);
-
-   if (info_ptr == NULL)
-      png_error(png_ptr, "OOM allocating info structure");
-
-   if (transforms < 0)
-      read_by_row(png_ptr, info_ptr, write_file, fp);
-
-   else
-      png_read_png(png_ptr, info_ptr, transforms, NULL/*params*/);
-
-   png_destroy_read_struct(&png_ptr, &info_ptr, NULL);
   return 1;
 }

@@ -190,7 +108,7 @@ static int mytime(struct timespec *t)
   return 0;
 }

-static int perform_one_test(FILE *fp, int nfiles, png_int_32 transforms)
+static int perform_one_test(FILE *fp, int nfiles)
 {
   int i;
   struct timespec before, after;
@@ -202,7 +120,7 @@ static int perform_one_test(FILE *fp, int nfiles, png_int_32 transforms)
   {
      for (i=0; i<nfiles; ++i)
      {
-         if (read_png(fp, transforms, NULL/*write*/))
+         if (read_png(fp))
         {
            if (ferror(fp))
            {
@@ -266,343 +184,120 @@ static int add_one_file(FILE *fp, char *name)

   if (ip != NULL)
   {
-      /* Read the file using libpng; this detects errors and also deals with
-       * files which contain data beyond the end of the file.
-       */
-      int ok = 0;
-      fpos_t pos;
-
-      if (fgetpos(fp, &pos))
+      int ch;
+      for (;;)
      {
-         /* Fatal error reading the start: */
-         perror("temporary file");
-         fprintf(stderr, "temporary file fgetpos error\n");
-         exit(1);
+         ch = getc(ip);
+         if (ch == EOF) break;
+         putc(ch, fp);
      }

-      if (read_png(ip, -1/*by row*/, fp/*output*/))
+      if (ferror(ip))
      {
-         if (ferror(ip))
-         {
-            perror(name);
-            fprintf(stderr, "%s: read error\n", name);
-         }
-
-         else
-            ok = 1; /* read ok */
+         perror(name);
+         fprintf(stderr, "%s: read error\n", name);
+         return 0;
      }

-      else
-         fprintf(stderr, "%s: file not added\n", name);
-
      (void)fclose(ip);

-      /* An error in the output is fatal; exit immediately: */
      if (ferror(fp))
      {
         perror("temporary file");
         fprintf(stderr, "temporary file write error\n");
-         exit(1);
-      }
-
-      if (ok)
-         return 1;
-
-      /* Did not read the file successfully, simply rewind the temporary
-       * file.  This must happen after the ferror check above to avoid clearing
-       * the error.
-       */
-      if (fsetpos(fp, &pos))
-      {
-         perror("temporary file");
-         fprintf(stderr, "temporary file fsetpos error\n");
-         exit(1);
+         return 0;
      }
   }

   else
   {
-      /* file open error: */
      perror(name);
      fprintf(stderr, "%s: open failed\n", name);
+      return 0;
   }

-   return 0; /* file not added */
-}
-
-static void
-usage(FILE *fp)
-{
-   if (fp != NULL) fclose(fp);
-
-   fprintf(stderr,
-"Usage:\n"
-" timepng --assemble <assembly> {files}\n"
-"  Read the files into <assembly>, output the count.  Options are ignored.\n"
-" timepng --dissemble <assembly> <count> [options]\n"
-"  Time <count> files from <assembly>, additional files may not be given.\n"
-" Otherwise:\n"
-"  Read the files into a temporary file and time the decode\n"
-"Transforms:\n"
-"  --by-image: read by image with png_read_png\n"
-"  --<transform>: implies by-image, use PNG_TRANSFORM_<transform>\n"
-"  Otherwise: read by row using png_read_row (to a single row buffer)\n"
-   /* ISO C90 string length max 509 */);fprintf(stderr,
-"{files}:\n"
-"  PNG files to copy into the assembly and time.  Invalid files are skipped\n"
-"  with appropriate error messages.  If no files are given the list of files\n"
-"  is read from stdin with each file name terminated by a newline\n"
-"Output:\n"
-"  For --assemble the output is the name of the assembly file followed by the\n"
-"  count of the files it contains; the arguments for --dissemble.  Otherwise\n"
-"  the output is the total decode time in seconds.\n");
-
-   exit(99);
+   return 1;
 }

 int main(int argc, char **argv)
 {
   int ok = 0;
-   int err = 0;
-   int nfiles = 0;
-   int transforms = -1; /* by row */
-   const char *assembly = NULL;
-   FILE *fp;
+   FILE *fp = tmpfile();

-   if (argc > 2 && strcmp(argv[1], "--assemble") == 0)
+   if (fp != NULL)
   {
-      /* Just build the test file, argv[2] is the file name. */
-      assembly = argv[2];
-      fp = fopen(assembly, "wb");
-      if (fp == NULL)
+      int err = 0;
+      int nfiles = 0;
+
+      if (argc > 1)
      {
-         perror(assembly);
-         fprintf(stderr, "timepng --assemble %s: could not open for write\n",
-               assembly);
-         usage(NULL);
-      }
+         int i;

-      argv += 2;
-      argc -= 2;
-   }
-
-   else if (argc > 3 && strcmp(argv[1], "--dissemble") == 0)
-   {
-      fp = fopen(argv[2], "rb");
-
-      if (fp == NULL)
-      {
-         perror(argv[2]);
-         fprintf(stderr, "timepng --dissemble %s: could not open for read\n",
-               argv[2]);
-         usage(NULL);
-      }
-
-      nfiles = atoi(argv[3]);
-      if (nfiles <= 0)
-      {
-         fprintf(stderr,
-               "timepng --dissemble <file> <count>: %s is not a count\n",
-               argv[3]);
-         exit(99);
-      }
-#ifdef __COVERITY__
-      else
-      {
-         nfiles &= PNG_UINT_31_MAX;
-      }
-#endif
-
-      argv += 3;
-      argc -= 3;
-   }
-
-   else /* Else use a temporary file */
-   {
-#ifndef __COVERITY__
-      fp = tmpfile();
-#else
-      /* Experimental. Coverity says tmpfile() is insecure because it
-       * generates predictable names.
-       *
-       * It is possible to satisfy Coverity by using mkstemp(); however,
-       * any platform supporting mkstemp() undoubtedly has a secure tmpfile()
-       * implementation as well, and doesn't need the fix.  Note that
-       * the fix won't work on platforms that don't support mkstemp().
-       *
-       * https://www.securecoding.cert.org/confluence/display/c/
-       * FIO21-C.+Do+not+create+temporary+files+in+shared+directories
-       * says that most historic implementations of tmpfile() provide
-       * only a limited number of possible temporary file names
-       * (usually 26) before file names are recycled. That article also
-       * provides a secure solution that unfortunately depends upon mkstemp().
-       */
-      char tmpfile[] = "timepng-XXXXXX";
-      int filedes;
-      umask(0177);
-      filedes = mkstemp(tmpfile);
-      if (filedes < 0)
-        fp = NULL;
-      else
-      {
-        fp = fdopen(filedes,"w+");
-        /* Hide the filename immediately and ensure that the file does
-         * not exist after the program ends
-         */
-        (void) unlink(tmpfile);
-      }
-#endif
-
-      if (fp == NULL)
-      {
-         perror("tmpfile");
-         fprintf(stderr, "timepng: could not open the temporary file\n");
-         exit(1); /* not a user error */
-      }
-   }
-
-   /* Handle the transforms: */
-   while (argc > 1 && argv[1][0] == '-' && argv[1][1] == '-')
-   {
-      const char *opt = *++argv + 2;
-
-      --argc;
-
-      /* Transforms turn on the by-image processing and maybe set some
-       * transforms:
-       */
-      if (transforms == -1)
-         transforms = PNG_TRANSFORM_IDENTITY;
-
-      if (strcmp(opt, "by-image") == 0)
-      {
-         /* handled above */
-      }
-
-#        define OPT(name) else if (strcmp(opt, #name) == 0)\
-         transforms |= PNG_TRANSFORM_ ## name
-
-      OPT(STRIP_16);
-      OPT(STRIP_ALPHA);
-      OPT(PACKING);
-      OPT(PACKSWAP);
-      OPT(EXPAND);
-      OPT(INVERT_MONO);
-      OPT(SHIFT);
-      OPT(BGR);
-      OPT(SWAP_ALPHA);
-      OPT(SWAP_ENDIAN);
-      OPT(INVERT_ALPHA);
-      OPT(STRIP_FILLER);
-      OPT(STRIP_FILLER_BEFORE);
-      OPT(STRIP_FILLER_AFTER);
-      OPT(GRAY_TO_RGB);
-      OPT(EXPAND_16);
-      OPT(SCALE_16);
-
-      else
-      {
-         fprintf(stderr, "timepng %s: unrecognized transform\n", opt);
-         usage(fp);
-      }
-   }
-
-   /* Handle the files: */
-   if (argc > 1 && nfiles > 0)
-      usage(fp); /* Additional files not valid with --dissemble */
-
-   else if (argc > 1)
-   {
-      int i;
-
-      for (i=1; i<argc; ++i)
-      {
-         if (nfiles == INT_MAX)
+         for (i=1; i<argc; ++i)
         {
-            fprintf(stderr, "%s: skipped, too many files\n", argv[i]);
-            break;
-         }
+            if (add_one_file(fp, argv[i]))
+               ++nfiles;

-         else if (add_one_file(fp, argv[i]))
-            ++nfiles;
-      }
-   }
-
-   else if (nfiles == 0) /* Read from stdin withoout --dissemble */
-   {
-      char filename[FILENAME_MAX+1];
-
-      while (fgets(filename, FILENAME_MAX+1, stdin))
-      {
-         size_t len = strlen(filename);
-
-         if (filename[len-1] == '\n')
-         {
-            filename[len-1] = 0;
-            if (nfiles == INT_MAX)
+            else
            {
-               fprintf(stderr, "%s: skipped, too many files\n", filename);
+               err = 1;
               break;
            }
-
-            else if (add_one_file(fp, filename))
-               ++nfiles;
-         }
-
-         else
-         {
-            fprintf(stderr, "timepng: file name too long: ...%s\n",
-               filename+len-32);
-            err = 1;
-            break;
         }
      }

-      if (ferror(stdin))
+      else
      {
-         fprintf(stderr, "timepng: stdin: read error\n");
-         err = 1;
-      }
-   }
+         char filename[FILENAME_MAX+1];

-   /* Perform the test, or produce the --assemble output: */
-   if (!err)
-   {
-      if (nfiles > 0)
-      {
-         if (assembly != NULL)
+         while (fgets(filename, FILENAME_MAX+1, stdin))
         {
-            if (fflush(fp) && !ferror(fp) && fclose(fp))
+            size_t len = strlen(filename);
+
+            if (filename[len-1] == '\n')
            {
-               perror(assembly);
-               fprintf(stderr, "%s: close failed\n", assembly);
+               filename[len-1] = 0;
+               if (add_one_file(fp, filename))
+                  ++nfiles;
+
+               else
+               {
+                  err = 1;
+                  break;
+               }
            }

            else
            {
-               printf("%s %d\n", assembly, nfiles);
-               fflush(stdout);
-               ok = !ferror(stdout);
+               fprintf(stderr, "timepng: truncated file name ...%s\n",
+                  filename+len-32);
+               err = 1;
+               break;
            }
         }

-         else
+         if (ferror(stdin))
         {
-            ok = perform_one_test(fp, nfiles, transforms);
-            (void)fclose(fp);
+            fprintf(stderr, "timepng: stdin: read error\n");
+            err = 1;
         }
      }

-      else
-         usage(fp);
+      if (!err)
+      {
+         if (nfiles > 0)
+            ok = perform_one_test(fp, nfiles);
+
+         else
+            fprintf(stderr, "usage: timepng {files} or ls files | timepng\n");
+      }
+
+      (void)fclose(fp);
   }

   else
-      (void)fclose(fp);
+      fprintf(stderr, "timepng: could not open temporary file\n");

   /* Exit code 0 on success. */
   return ok == 0;
 }
-#else /* !sufficient support */
-int main(void) { return 77; }
-#endif /* !sufficient support */
--- a/contrib/pngminus/png2pnm.c
+++ b/contrib/pngminus/png2pnm.c
@@ -266,7 +266,7 @@ BOOL png2pnm (FILE *png_file, FILE *pnm_file, FILE *alpha_file,
    png_set_expand (png_ptr);

 #ifdef NJET
-  /* downgrade 16-bit images to 8-bit */
+  /* downgrade 16-bit images to 8 bit */
  if (bit_depth == 16)
    png_set_strip_16 (png_ptr);
  /* transform grayscale images into full-color */
--- a/contrib/pngminus/pnm2png.c
+++ b/contrib/pngminus/pnm2png.c
@@ -3,7 +3,6 @@
 *  copyright (C) 1999 by Willem van Schaik <willem@schaik.com>
 *
 *  version 1.0 - 1999.10.15 - First version.
- *  version 1.1 - 2015.07.29 - Fixed leaks (Glenn Randers-Pehrson)
 *
 *  Permission to use, copy, modify, and distribute this software and
 *  its documentation for any purpose and without fee is hereby granted,
@@ -201,17 +200,17 @@ BOOL pnm2png (FILE *pnm_file, FILE *png_file, FILE *alpha_file, BOOL interlace,
  char          width_token[16];
  char          height_token[16];
  char          maxval_token[16];
-  volatile int    color_type=1;
+  volatile int           color_type;
  unsigned long   ul_width=0, ul_alpha_width=0;
  unsigned long   ul_height=0, ul_alpha_height=0;
  unsigned long   ul_maxval=0;
-  volatile png_uint_32   width=0, height=0;
-  volatile png_uint_32   alpha_width=0, alpha_height=0;
+  volatile png_uint_32   width, height;
+  volatile png_uint_32   alpha_width, alpha_height;
  png_uint_32   maxval;
  volatile int           bit_depth = 0;
-  int           channels=0;
+  int           channels;
  int           alpha_depth = 0;
-  int           alpha_present=0;
+  int           alpha_present;
  int           row, col;
  BOOL          raw, alpha_raw = FALSE;
 #if defined(PNG_WRITE_INVERT_SUPPORTED) || defined(PNG_WRITE_PACK_SUPPORTED)
@@ -357,10 +356,8 @@ BOOL pnm2png (FILE *pnm_file, FILE *png_file, FILE *alpha_file, BOOL interlace,
    channels = 3;
  else if (color_type == PNG_COLOR_TYPE_RGB_ALPHA)
    channels = 4;
-#if 0
  else
-    channels = 0; /* cannot happen */
-#endif
+    channels = 0; /* should not happen */

  alpha_present = (channels - 1) % 2;

@@ -432,16 +429,12 @@ BOOL pnm2png (FILE *pnm_file, FILE *png_file, FILE *alpha_file, BOOL interlace,
      NULL);
  if (!png_ptr)
  {
-    free (png_pixels);
-    png_pixels = NULL;
    return FALSE;
  }
  info_ptr = png_create_info_struct (png_ptr);
  if (!info_ptr)
  {
    png_destroy_write_struct (&png_ptr, (png_infopp) NULL);
-    free (png_pixels);
-    png_pixels = NULL;
    return FALSE;
  }

@@ -456,9 +449,7 @@ BOOL pnm2png (FILE *pnm_file, FILE *png_file, FILE *alpha_file, BOOL interlace,
  /* setjmp() must be called in every function that calls a PNG-reading libpng function */
  if (setjmp (png_jmpbuf(png_ptr)))
  {
-    png_destroy_write_struct (&png_ptr, &info_ptr);
-    free (png_pixels);
-    png_pixels = NULL;
+    png_destroy_write_struct (&png_ptr, (png_infopp) NULL);
    return FALSE;
  }

@@ -479,9 +470,7 @@ BOOL pnm2png (FILE *pnm_file, FILE *png_file, FILE *alpha_file, BOOL interlace,
    if ((row_pointers = (png_byte **)
        malloc (height * sizeof (png_bytep))) == NULL)
    {
-      png_destroy_write_struct (&png_ptr, &info_ptr);
-      free (png_pixels);
-      png_pixels = NULL;
+      png_destroy_write_struct (&png_ptr, (png_infopp) NULL);
      return FALSE;
    }
  }
@@ -497,7 +486,7 @@ BOOL pnm2png (FILE *pnm_file, FILE *png_file, FILE *alpha_file, BOOL interlace,
  png_write_end (png_ptr, info_ptr);

  /* clean up after the write, and free any memory allocated */
-  png_destroy_write_struct (&png_ptr, &info_ptr);
+  png_destroy_write_struct (&png_ptr, (png_infopp) NULL);

  if (row_pointers != (unsigned char**) NULL)
    free (row_pointers);
--- a/contrib/pngsuite/README
+++ b/contrib/pngsuite/README
@@ -1,8 +1,8 @@

 pngsuite
 --------
-Copyright (c) Willem van Schaik, 1999, 2011, 2012
-Two images (ftbbn0g01.png and ftbbn0g02.png) are by Glenn Randers-Pehrson, 2012
+(c) Willem van Schaik, 1999, 2011, 2012
+Two images are by Glenn Randers-Pehrson, 2012

 Permission to use, copy, modify, and distribute these images for any
 purpose and without fee is hereby granted.
--- a/contrib/testpngs/gray-1-1.8-tRNS.png
+++ b/contrib/testpngs/gray-1-1.8-tRNS.png
--- a/contrib/testpngs/gray-1-1.8.png
+++ b/contrib/testpngs/gray-1-1.8.png
--- a/contrib/testpngs/gray-1-linear-tRNS.png
+++ b/contrib/testpngs/gray-1-linear-tRNS.png
--- a/contrib/testpngs/gray-1-linear.png
+++ b/contrib/testpngs/gray-1-linear.png
--- a/contrib/testpngs/gray-1-sRGB-tRNS.png
+++ b/contrib/testpngs/gray-1-sRGB-tRNS.png
--- a/contrib/testpngs/gray-1-sRGB.png
+++ b/contrib/testpngs/gray-1-sRGB.png
--- a/contrib/testpngs/gray-1-tRNS.png
+++ b/contrib/testpngs/gray-1-tRNS.png
--- a/contrib/testpngs/gray-1.png
+++ b/contrib/testpngs/gray-1.png
--- a/contrib/testpngs/gray-16-1.8-tRNS.png
+++ b/contrib/testpngs/gray-16-1.8-tRNS.png
--- a/contrib/testpngs/gray-16-1.8.png
+++ b/contrib/testpngs/gray-16-1.8.png
--- a/contrib/testpngs/gray-16-linear-tRNS.png
+++ b/contrib/testpngs/gray-16-linear-tRNS.png
--- a/contrib/testpngs/gray-16-linear.png
+++ b/contrib/testpngs/gray-16-linear.png
--- a/contrib/testpngs/gray-16-sRGB-tRNS.png
+++ b/contrib/testpngs/gray-16-sRGB-tRNS.png
--- a/contrib/testpngs/gray-16-sRGB.png
+++ b/contrib/testpngs/gray-16-sRGB.png
--- a/contrib/testpngs/gray-16-tRNS.png
+++ b/contrib/testpngs/gray-16-tRNS.png
--- a/contrib/testpngs/gray-16.png
+++ b/contrib/testpngs/gray-16.png
--- a/contrib/testpngs/gray-2-1.8-tRNS.png
+++ b/contrib/testpngs/gray-2-1.8-tRNS.png
--- a/contrib/testpngs/gray-2-1.8.png
+++ b/contrib/testpngs/gray-2-1.8.png
--- a/contrib/testpngs/gray-2-linear-tRNS.png
+++ b/contrib/testpngs/gray-2-linear-tRNS.png
--- a/contrib/testpngs/gray-2-linear.png
+++ b/contrib/testpngs/gray-2-linear.png
--- a/contrib/testpngs/gray-2-sRGB-tRNS.png
+++ b/contrib/testpngs/gray-2-sRGB-tRNS.png
--- a/contrib/testpngs/gray-2-sRGB.png
+++ b/contrib/testpngs/gray-2-sRGB.png
--- a/contrib/testpngs/gray-2-tRNS.png
+++ b/contrib/testpngs/gray-2-tRNS.png
--- a/contrib/testpngs/gray-2.png
+++ b/contrib/testpngs/gray-2.png
--- a/contrib/testpngs/gray-4-1.8-tRNS.png
+++ b/contrib/testpngs/gray-4-1.8-tRNS.png
--- a/contrib/testpngs/gray-4-1.8.png
+++ b/contrib/testpngs/gray-4-1.8.png
--- a/contrib/testpngs/gray-4-linear-tRNS.png
+++ b/contrib/testpngs/gray-4-linear-tRNS.png
--- a/contrib/testpngs/gray-4-linear.png
+++ b/contrib/testpngs/gray-4-linear.png
--- a/contrib/testpngs/gray-4-sRGB-tRNS.png
+++ b/contrib/testpngs/gray-4-sRGB-tRNS.png
--- a/contrib/testpngs/gray-4-sRGB.png
+++ b/contrib/testpngs/gray-4-sRGB.png
--- a/contrib/testpngs/gray-4-tRNS.png
+++ b/contrib/testpngs/gray-4-tRNS.png
--- a/contrib/testpngs/gray-4.png
+++ b/contrib/testpngs/gray-4.png
--- a/contrib/testpngs/gray-8-1.8-tRNS.png
+++ b/contrib/testpngs/gray-8-1.8-tRNS.png
--- a/contrib/testpngs/gray-8-1.8.png
+++ b/contrib/testpngs/gray-8-1.8.png
--- a/contrib/testpngs/gray-8-linear-tRNS.png
+++ b/contrib/testpngs/gray-8-linear-tRNS.png
--- a/contrib/testpngs/gray-8-linear.png
+++ b/contrib/testpngs/gray-8-linear.png
--- a/contrib/testpngs/gray-8-sRGB-tRNS.png
+++ b/contrib/testpngs/gray-8-sRGB-tRNS.png
--- a/contrib/testpngs/gray-8-sRGB.png
+++ b/contrib/testpngs/gray-8-sRGB.png
--- a/contrib/testpngs/gray-8-tRNS.png
+++ b/contrib/testpngs/gray-8-tRNS.png
--- a/contrib/testpngs/gray-8.png
+++ b/contrib/testpngs/gray-8.png
--- a/contrib/testpngs/gray-alpha-16-1.8.png
+++ b/contrib/testpngs/gray-alpha-16-1.8.png
--- a/contrib/testpngs/gray-alpha-16-linear.png
+++ b/contrib/testpngs/gray-alpha-16-linear.png
--- a/contrib/testpngs/gray-alpha-16-sRGB.png
+++ b/contrib/testpngs/gray-alpha-16-sRGB.png
--- a/contrib/testpngs/gray-alpha-16.png
+++ b/contrib/testpngs/gray-alpha-16.png
--- a/contrib/testpngs/gray-alpha-8-1.8.png
+++ b/contrib/testpngs/gray-alpha-8-1.8.png
--- a/contrib/testpngs/gray-alpha-8-linear.png
+++ b/contrib/testpngs/gray-alpha-8-linear.png
--- a/contrib/testpngs/gray-alpha-8-sRGB.png
+++ b/contrib/testpngs/gray-alpha-8-sRGB.png
--- a/contrib/testpngs/gray-alpha-8.png
+++ b/contrib/testpngs/gray-alpha-8.png
--- a/contrib/testpngs/makepngs.sh
+++ b/contrib/testpngs/makepngs.sh
@@ -1,94 +0,0 @@
-#!/bin/sh
-#
-# Make a set of test PNG files, MAKEPNG is the name of the makepng executable
-# built from contrib/libtests/makepng.c
-
-# Copyright (c) 2015 John Cunningham Bowler
-
-# Last changed in libpng 1.7.0 [(PENDING RELEASE)]
-
-# This code is released under the libpng license.
-# For conditions of distribution and use, see the disclaimer
-# and license in png.h
-
-# The arguments say whether to build all the files or whether just to build the
-# ones that extend the code-coverage of libpng from the existing test files in
-# contrib/pngsuite.
-test -n "$MAKEPNG" || MAKEPNG=./makepng
-opts=
-
-mp(){
-   ${MAKEPNG} $opts $1 "$3" "$4" "$3-$4$2.png"
-}
-
-mpg(){
-   if test "$1" = "none"
-   then
-      mp "" "" "$2" "$3"
-   else
-      mp "--$1" "-$1" "$2" "$3"
-   fi
-}
-
-mptrans(){
-   if test "$1" = "none"
-   then
-      mp "--tRNS" "-tRNS" "$2" "$3"
-   else
-      mp "--tRNS --$1" "-$1-tRNS" "$2" "$3"
-   fi
-}
-
-case "$1" in
-   --small)
-      opts="--small";;&
-
-   --all|--small)
-      for g in none sRGB linear 1.8
-      do
-         for c in gray palette
-         do
-            for b in 1 2 4
-            do
-               mpg "$g" "$c" "$b"
-               mptrans "$g" "$c" "$b"
-            done
-         done
-
-         mpg "$g" palette 8
-         mptrans "$g" palette 8
-
-         for b in 8 16
-         do
-            for c in gray gray-alpha rgb rgb-alpha
-            do
-               mpg "$g" "$c" "$b"
-            done
-            for c in gray rgb
-            do
-               mptrans "$g" "$c" "$b"
-            done
-         done
-      done;;
-
-   --coverage)
-      # Comments below indicate cases known to be required and not duplicated
-      # in other (required) cases; the aim is to get a minimal set that gives
-      # the maxium code coverage.
-      mpg none gray-alpha 8 # required: code coverage, sRGB opaque component
-      mpg none palette 8 # required: basic palette read
-      mpg 1.8 gray 2 # required: tests gamma threshold code
-      mpg 1.8 palette 2 # required: code coverage
-      mpg 1.8 palette 4 # required: code coverage
-      mpg 1.8 palette 8 # error limits only
-      mpg linear palette 8 # error limits only
-      mpg linear rgb-alpha 16 # error limits only
-      mpg sRGB palette 1 # required: code coverage
-      mpg sRGB rgb-alpha 16 # required: code coverage: pngread.c:2422 untested
-      :;;
-
-   *)
-      echo "$0 $1: unknown argument, usage:" >&2
-      echo "  $0 [--all|--coverage|--small]" >&2
-      exit 1
-esac
--- a/contrib/testpngs/palette-1-1.8-tRNS.png
+++ b/contrib/testpngs/palette-1-1.8-tRNS.png
--- a/contrib/testpngs/palette-1-1.8.png
+++ b/contrib/testpngs/palette-1-1.8.png
--- a/contrib/testpngs/palette-1-linear-tRNS.png
+++ b/contrib/testpngs/palette-1-linear-tRNS.png
--- a/contrib/testpngs/palette-1-linear.png
+++ b/contrib/testpngs/palette-1-linear.png
--- a/contrib/testpngs/palette-1-sRGB-tRNS.png
+++ b/contrib/testpngs/palette-1-sRGB-tRNS.png
--- a/contrib/testpngs/palette-1-sRGB.png
+++ b/contrib/testpngs/palette-1-sRGB.png
--- a/contrib/testpngs/palette-1-tRNS.png
+++ b/contrib/testpngs/palette-1-tRNS.png
--- a/contrib/testpngs/palette-1.png
+++ b/contrib/testpngs/palette-1.png
--- a/contrib/testpngs/palette-2-1.8-tRNS.png
+++ b/contrib/testpngs/palette-2-1.8-tRNS.png
--- a/contrib/testpngs/palette-2-1.8.png
+++ b/contrib/testpngs/palette-2-1.8.png
--- a/contrib/testpngs/palette-2-linear-tRNS.png
+++ b/contrib/testpngs/palette-2-linear-tRNS.png
--- a/contrib/testpngs/palette-2-linear.png
+++ b/contrib/testpngs/palette-2-linear.png
--- a/contrib/testpngs/palette-2-sRGB-tRNS.png
+++ b/contrib/testpngs/palette-2-sRGB-tRNS.png
--- a/contrib/testpngs/palette-2-sRGB.png
+++ b/contrib/testpngs/palette-2-sRGB.png
--- a/contrib/testpngs/palette-2-tRNS.png
+++ b/contrib/testpngs/palette-2-tRNS.png
--- a/Show More
+++ b/Show More