commit bf51c644f7d29400d884e20def9a0bee74904308
Author: John Bowler <jbowler@acm.org>
Date: Tue Sep 22 09:05:13 2015 -0700
Updated contrib/testpngs/*.png
Corrected copyright/licensing information, corrected filtering.
Signed-off-by: John Bowler <jbowler@acm.org>
commit 05399c8c82d7b188357dc6fa05a8cdd89426b155
Author: John Bowler <jbowler@acm.org>
Date: Tue Sep 22 09:04:03 2015 -0700
makepng.c: correct the first row filter setting
It needs to include the "UP" filter so that libpng knows to retain the first
line for the UP filter on the next one. Without this libpng ended up using NONE
for the second line.
Signed-off-by: John Bowler <jbowler@acm.org>
commit 8fae6609c063c7e0a5eeb592f8eec15849617ae9
Author: John Bowler <jbowler@acm.org>
Date: Mon Sep 21 17:15:45 2015 -0700
makepng: spelling corrections, single test output
Corrections to some obvious mistakes, plus one output file.
Signed-off-by: John Bowler <jbowler@acm.org>
commit a2245a2c54a679d25f8f1609f85654d155936863
Author: John Bowler <jbowler@acm.org>
Date: Mon Sep 21 13:39:48 2015 -0700
Updated testpngs files with new Licensing tag
Signed-off-by: John Bowler <jbowler@acm.org>
commit 46d3f863cace5b7aa769c9b882fca49e2a821138
Author: John Bowler <jbowler@acm.org>
Date: Mon Sep 21 13:38:34 2015 -0700
Updated makepng.c
This supports more test cases and a reduced licence keyword (now licensing).
The extra text cases require more slack in pngstest.c
Signed-off-by: John Bowler <jbowler@acm.org>
commit 7c9a08b8bc5e2542184d4abb25c33c516bc0adc7
Author: John Bowler <jbowler@acm.org>
Date: Sun Sep 20 20:55:19 2015 -0700
Test PNG files
These files were generated by contrib/testpngs/makepngs.sh --small with MAKEPNG
set to the makepng compiled from the current contrib/libtests/makepngs.sh
Signed-off-by: John Bowler <jbowler@acm.org>
commit c2a8a01b2ac733b8029478d10f700f5ab8a713f2
Author: John Bowler <jbowler@acm.org>
Date: Sun Sep 20 20:51:06 2015 -0700
makepng --small
This patch adds code to 'makepng' to allow the generation of smaller images that
also give better test case coverage. It also adds copyright and licence to the
generated images, reflecting the fact that they are original works of the author
of the code. The licence used is the Creative Commons Public Domain one,
appropriate to a non-source-code work.
The resultant image were used to generate the updated pngstest-errors.h file in
a prior commit.
Signed-off-by: John Bowler <jbowler@acm.org>
commit 8c025bcf3fdfb68fb8b1e5fab4b7deb0f94453f6
Author: John Bowler <jbowler@acm.org>
Date: Sun Sep 20 20:40:52 2015 -0700
Simplified API sRGB gamma handling correction
If a gamma encoded file that has a gamma not matching that of sRGB is passed to
the simplified API the previous code simply interpreted it as a power law
encoding. However old Mac files had a power law correction of 1.45 built in to
the encoding, even though the display devices were consistent with sRGB.
Assuming a power law encoding results in substantial differences in the
interpretation of low 8-bit values; below 10. For example an Apple '5' which is
equivalent to an sRGB '17' ends up as the value '8'.
This patch provides some measure of correction for this by making the gamma
correction done within the simplified API assume that any encoded data is
encoded relative to an sRGB-like transfer function; the data is corrected back
to the PNG-nominal 2.2 value then decoded to linear (if required) using the sRGB
transfer function.
This reduces the errors reported by pngstest for such files (colormapped ones)
but still leaves the issue with files where the standard libpng code does the
gamma decoding. To cope with the latter cases the patch also includes a new
pngstest-errors which allows the result, however this is still a
work-in-progress; a better solution is possible.
Signed-off-by: John Bowler <jbowler@acm.org>
These should fix most of the reported Coverity issues. The remaining issues
should be the back_b etc assignments, which look like a Coverity bug, and
passing a pointer to a byte to a function that expects a pointer to one or more
bytes, which should (I believe) be fixed in one case and not the other
(next_filter) case; the latter case will probably go away as I am going to
rewrite that piece of code to avoid a spurious buffer allocation.
Signed-off-by: John Bowler <jbowler@acm.org>
because usleep() is deprecated (port from libpng16).
Fixed potential leak of png_pixels in contrib/pngminus/pnm2png.c
Fixed uninitialized variable in contrib/gregbook/rpng2-x.c
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.
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).
depend on READ_TRANSFORMS and moves all the transform gamma (READ_GAMMA)
code from elsewhere to png_tran.c. There are no code changes.
There is one remaining use of the gamma (16-bit) code in the simplified
API in pngread.c but that is because of a long-standing libpng bug,
namely that the gamma corrected palette is no produced by
png_read_update_info (John Bowler).
pngstest.c, and pngimage.c. Most seem harmless, but png-fix-itxt
would only work with iTXt chunks with length 255 or less.
Fixed cexcept.h in which GCC 5 reported that one of the auto
variables in the Try macro needs to be volatile to prevent value
being lost over the setjmp, and fixed g++ build breaks (John Bowler).
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.
internal struct (png_transform_control) to replace row_info and uses
that to implement affirms correctly. The change also adds checks on
the rowbytes calculation and additional checks on most transform
implementations.
Added png_uint_16 range checking, pngvalid tRNS, fixed png_uint_16:
review of previous checks, removal of some where SAFE. pngvalid: add
testing of tRNS for better code coverage pngvalid: correct rgb-to-gray
error calculations. Code coverage is still incomplete: see /*UNTESTED*/
in pngrtran.c
added RELEASE/!RELEASE convenience macros. png_muldiv_warn was used in
only one place, and the overflow condition is a genuine warning not
an internal error. Four macros allow code or function parameters to be
condition on RELEASE (or not) builds and tidy up the #ifdef handling of
functions.
where the code depended on the build base type and can be defined on
the command line, allowing testing in beta builds. Overflows previously
handled by png_warning in png.c have been changed to use new
macros/affirm functions so that beta builds will abort on overflow and
release builds will quietly ignore it. This avoids release builds
producing warnings that are of no use to end users.
Added 'assert' based overflow checking for debug builds for char
and short assignments. Simply ignore the error in release builds
(a truncated value will be used without warning). Controlled by
PNG_RANGE_CHECK_SUPPORTED.
