Libpng 1.5.27 - May 26, 2016

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

   libpng-1.5.27.tar.xz (LZMA-compressed, recommended)
   libpng-1.5.27.tar.gz

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

   lpng1527.7z  (LZMA-compressed, recommended)
   lpng1527.zip

Other information:

   libpng-1.5.27-README.txt
   libpng-1.5.27-LICENSE.txt
   libpng-1.5.27-*.asc (armored detached GPG signatures)

Changes since the last public release (1.5.26):

  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.
  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.
  In projects/vstudio, combined readme.txt and WARNING into README.txt
  Worked around a false-positive Coverity issue in pngvalid.c.
  Only use exit(77) from pngvalid.c in configure builds.
  Updated CMakeLists.txt, added supporting scripts/gen*.cmake.in
    and test.cmake.in (Roger Leigh).
  Added a common-law trademark notice and export control information
    to the LICENSE file, png.h, and the man page.
  Changed PNG_INFO_cHNK and PNG_FREE_cHNK from 0xnnnn to 0xnnnnU in png.h
    (Robert C. Seacord).
  Fixed some misleading indentation in pngvalid.c (Krishnaraj Bhat).
  Fixed typo (missing underscore) in #define PNG_READ_16_TO_8_SUPPORTED
    Bug report by (Y.Ohashik).
  Added PNG_FAST_FILTERS macro (defined as
    PNG_FILTER_NONE|PNG_FILTER_SUB|PNG_FILTER_UP).

Send comments/corrections/commendations to png-mng-implement at lists.sf.net
(subscription required; visit
https://lists.sourceforge.net/lists/listinfo/png-mng-implement
to subscribe)
or to glennrp at users.sourceforge.net

Glenn R-P