1 Libpng 1.6.21 - January 15, 2016
3 This is a public release of libpng, intended for use in production codes.
5 Files available for download:
7 Source files with LF line endings (for Unix/Linux) and with a
10 libpng-1.6.21.tar.xz (LZMA-compressed, recommended)
13 Source files with CRLF line endings (for Windows), without the
16 /scratch/glennrp/Libpng16/lpng1621.7z (LZMA-compressed, recommended)
17 /scratch/glennrp/Libpng16/lpng1621.zip
21 libpng-1.6.21-README.txt
22 libpng-1.6.21-LICENSE.txt
23 libpng-1.6.21-*.asc (armored detached GPG signatures)
25 Changes since the last public release (1.6.20):
27 Fixed syntax "$(command)" in tests/pngstest that some shells other than
28 bash could not parse (Bug report by Nelson Beebe). Use `command` instead.
29 Moved png_check_keyword() from pngwutil.c to pngset.c
30 Removed LE/BE dependencies in pngvalid, to 'fix' the current problem
31 in the BigEndian tests by not testing it, making the BE code the same
33 Fixes to pngvalid for various reduced build configurations (eliminate unused
34 statics) and a fix for the case in rgb_to_gray when the digitize option
35 reduces graylo to 0, producing a large error.
36 Widened the 'limit' check on the internally calculated error limits in
37 the 'DIGITIZE' case (the code used prior to 1.7 for rgb_to_gray error
38 checks) and changed the check to only operate in non-release builds
39 (base build type not RC or RELEASE.)
40 Fixed undefined behavior in pngvalid.c, undefined because
41 (png_byte) << shift is undefined if it changes the signed bit
42 (because png_byte is promoted to int). The libpng exported functions
43 png_get_uint_32 and png_get_uint_16 handle this. (Bug reported by
44 David Drysdale as a result of reports from UBSAN in clang 3.8).
45 This changes pngvalid to use BE random numbers; this used to produce
46 errors but these should not be fixed as a result of the previous changes.
47 In projects/vstudio, combined readme.txt and WARNING into README.txt
48 Relocated assert() in contrib/tools/pngfix.c, bug found by American
49 Fuzzy Lop, reported by Brian Carpenter.
50 Marked 'limit' UNUSED in transform_range_check(). This only affects
52 Worked around a false-positive Coverity issue in pngvalid.c.
54 Send comments/corrections/commendations to png-mng-implement at lists.sf.net
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56 https://lists.sourceforge.net/lists/listinfo/png-mng-implement
58 or to glennrp at users.sourceforge.net