the #ifdef PNG_SET_UNKNOWN_CHUNKS_SUPPORTED/#endif block.
Removed recently-added #ifdef from pngpread.c; moving the prototype
in pngpriv.h fixed the compiler warning that the #ifdef was trying
to solve.
or intrinsics to be turned on during the build by defining
PNG_ARM_NEON_IMPLEMENTATION to the correct value (2 or 1). The
default is "undefined" and the build type is selected in pngpriv.h.
off. Also fixed the pngminim makefiles to work when $(MAKEFLAGS) contains stuff
which terminates the make options (as by default in recent versions of Gentoo).
png_chunk_unknown_handling() function, and restored the unknown-chunk
handling code from libpng-1.6.6.
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strip option. pngfix relied on undefined behavior and even a simple change from
gcc to g++ caused it to fail. The new strip option 'unsafe' has been
implemented and is the default if --max is given. Option names have
been clarified, with --strip=transform now stripping the bKGD chunk,
which was stripped previously with --strip=unused.
Added all documented chunk types to pngpriv.h
Previous iOS/Xcode fixes for the ARM NEON optimizations moved the test
on __ARM_NEON__ from configure time to compile time. This breaks symbol
prefixing because the definition of the special png_init_filter_functions
call was hidden at configure time if the relevant compiler arguments are
passed in CFLAGS as opposed to CC. This change attempts to avoid all
the confusion that would result by declaring the init function even when
it is not used, so that it will always get prefixed.
pnglibconf.h, allowing more of the decisions to be made internally
(pngpriv.h) during the compile. Without this, symbol prefixing is broken
under certain circumstances on ARM platforms. Now only the API parts of
the optimizations ('check' vs 'api') are exposed in the public header files
except that the new setting PNG_ARM_NEON_OPT documents how libpng makes the
decision about whether or not to use the optimizations.
management system (CMS). In practice it is not possible to obtain cHRM
information reliably using just the end-point tags because they do not exist
in the vast majority of profiles. Instead it is necessary to run the endpoints
through the ICC colorimetric intent transform (as described in the v4
spec). Since this is likely to be too much code inside libpng for too
little gain (it implies a fairly complete CMS implementation) the code
has been changed to allow an external CMS to be used. This code is
temporarily disabled until a suitable set of test cases using one or more
external CMS implementations have been implemented.
fixed Cygwin+MSVC build errors. The ICC profile handling now includes more
checking. Several errors that caused rejection of the profile are now
handled with a warning in such a way that the invalid profiles will be
read by default in release (but not pre-RC) builds but will not be
written by default. The easy part of handling a cHRM chunk is written,
where the ICC profile contains the required data. The more difficult
part plus guessing a gAMA value requires code to pass selected RGB values
through the profile.
contrib/libtests/makepng: corrected 'rgb' and 'gray' cases. profile_error
messages could be truncated; made a correct buffer size calculation and
adjusted pngerror.c appropriately. png_icc_check_* checking improved;
changed the functions to receive the correct color type of the PNG on read
or write and check that it matches the color space of the profile (despite
what the comments said before, there is danger in assuming the app will
cope correctly with an RGB profile on a grayscale image and, since it
violates the PNG spec, allowing it is certain to produce inconsistent
app behavior and might even cause app crashes.) Check that profiles
contain the tags needed to process the PNG (tags all required by the ICC
spec). Removed unused PNG_STATIC from pngpriv.h.
control of the unknown handling, corrects the pre-existing bug where
the per-chunk 'keep' setting is ignored and makes it possible to skip
IDAT chunks in the sequential reader (broken in earlier 1.6 versions).
There is a new test program, test-unknown.c, which is a work in progress
(not currently part of the test suite). Comments in the header files now
explain how the unknown handling works.
on read and write. In libpng 1.6 the two cases can be distinguished and
considerable code cleanup, and extra error checking, is possible. This
makes calls on the write side that have no effect be ignored with a
png_app_error(), which can be disabled in the app using
png_set_benign_errors(), and removes the spurious use of usr_channels
on the read side.
Because of the changes to support symbol prefixing PNG_INTERNAL_FUNCTION
declares floating point APIs during libpng builds even if they are completely
disabled. This requires the png floating point types (png_double*) to be
declared even though the functions are never actually defined. This
change provides a dummy definition so that the declarations work, yet any
implementation will fail to compile because of an incomplete type.
on alignment increasing pointer casts when -Wcast-align is passed. This
fixes the cases clang warns about either (pngread.c) by eliminating the
casts from png_bytep to png_uint_16p or, for pngrutil.c where the cast
is previously verified or pngstest.c where it is OK by introducing new
png_aligncast macros to do the cast in a way that clang accepts.
