- Fixed some 64-bit type conversion warnings in pngrtran.c
- Moved row_info from png_struct to a local variable.
- The various interlace mask arrays have been made into arrays of
- bytes and made PNG_CONST and static (previously some arrays were
- marked PNG_CONST and some weren't).
- Additional checks have been added to the transform code to validate the
- pixel depths after the transforms on both read and write.
- Removed some redundant code from pngwrite.c, in png_desgtroy_write_struct().
- Changed chunk reading/writing code to use png_uint_32 instead of png_byte[4].
- This removes the need to allocate temporary strings for chunk names on
- the stack in the read/write code. Unknown chunk handling still uses the
- string form because this is exposed in the API.
- Added a note in the manual the png_read_update_info() must be called only
- once with a particular info_ptr.
- Revised test-pngtest.sh to report FAIL when pngtest fails.
- Added "--strict" option to pngtest, to report FAIL when the failure is
- only because the resulting valid files are different.
- Revised CMakeLists.txt to work with mingw and removed some material from
- CMakeLists.txt that is no longer useful in libpng-1.5.
- Fixed typo in Makefile.in and Makefile.am ("-M Wl" should be "-M -Wl")."
- Speed up png_combine_row() for interlaced images. This reduces the generality
- of the code, allowing it to be optimized for Adam7 interlace. The masks
- passed to png_combine_row() are now generated internally, avoiding
- some code duplication and localizing the interlace handling somewhat.
- Align png_struct::row_buf - previously it was always unaligned, caused by
- a bug in the code that attempted to align it; the code needs to subtract
- one from the pointer to take account of the filter byte prepended to
- each row.
- Optimized png_combine_row() when rows are aligned. This gains a small
- percentage for 16-bit and 32-bit pixels in the typical case where the
- output row buffers are appropriately aligned. The optimization was not
- previously possible because the png_struct buffer was always misaligned.
- Removed two redundant tests for unitialized row.
- Fixed a relatively harmless memory overwrite in compressed text writing
- with a 1 byte zlib buffer.
- Add ability to call png_read_update_info multiple times to pngvalid.c
- Fixes for multiple calls to png_read_update_info. These fixes attend to
- most of the errors revealed in pngvalid, however doing the gamma work
- twice results in inaccuracies that can't be easily fixed. There is now
- a warning in the code if this is going to happen.
- Turned on multiple png_read_update_info in pngvalid transform tests.
- Prevent libpng from overwriting unused bits at the end of the image when
- it is not byte aligned, while reading. Prior to libpng-1.5.6 libpng would
- overwrite the partial byte at the end of each row if the row width was not
- an exact multiple of 8 bits and the image is not interlaced.
- Made png_ptr->prev_row an aligned pointer into png_ptr->big_prev_row
- (Mans Rullgard).
- Changed misleading "Missing PLTE before cHRM" warning to "Out of place cHRM"
- Added PNG_LSR() and PNG_LSL() macros to defend against buggy compilers that
- evaluate non-taken code branches and complain about out-of-range shifts.
- Renamed the local variable 'byte' because it appears in a MSYS header
- file.
- Added #define PNG_ALIGN_TYPE PNG_ALIGN_NONE to contrib/pngminim/*/pngusr.h
+Changes since the last public release (1.5.6):
+ Added support for ARM processor (Mans Rullgard)
+ Fixed bug in pngvalid on early allocation failure; fixed type cast in
+ pngmem.c; pngvalid would attempt to call png_error() if the allocation
+ of a png_struct or png_info failed. This would probably have led to a
+ crash. The pngmem.c implementation of png_malloc() included a cast
+ to png_size_t which would fail on large allocations on 16-bit systems.
+ Fix for the preprocessor of the Intel C compiler. The preprocessor
+ splits adjacent @ signs with a space; this changes the concatentation
+ token from @-@-@ to PNG_JOIN; that should work with all compiler
+ preprocessors.
+ Paeth filter speed improvements from work by Siarhei Siamashka. This
+ changes the 'Paeth' reconstruction function to improve the GCC code
+ generation on x86. The changes are only part of the suggested ones;
+ just the changes that definitely improve speed and remain simple.
+ The changes also slightly increase the clarity of the code.
+ Check compression_type parameter in png_get_iCCP and remove spurious
+ casts. The compression_type parameter is always assigned to, so must
+ be non-NULL. The cast of the profile length potentially truncated the
+ value unnecessarily on a 16-bit int system, so the cast of the (byte)
+ compression type to (int) is specified by ANSI-C anyway.
+ Fixed FP division by zero in pngvalid.c; the 'test_pixel' code left
+ the sBIT fields in the test pixel as 0, which resulted in a floating
+ point division by zero which was irrelevant but causes systems where
+ FP exceptions cause a crash. Added code to pngvalid to turn on FP
+ exceptions if the appropriate glibc support is there to ensure this is
+ tested in the future.
+ Added versioning to pnglibconf.h comments.
+ Installed more accurate linear to sRGB conversion tables. The slightly
+ modified tables reduce the number of 16-bit values that
+ convert to an off-by-one 8-bit value. The "makesRGB.c" code that was used
+ to generate the tables is now in a contrib/sRGBtables sub-directory.
+ Added run-time detection of NEON support.
+ Multiple transform bug fixes plus a work-round for double gamma correction.
+ libpng does not support more than one transform that requires linear data
+ at once - if this is tried typically the results is double gamma
+ correction. Since the simplified APIs can need rgb to gray combined with
+ a compose operation it is necessary to do one of these outside the main
+ libpng transform code. This check-in also contains fixes to various bugs
+ in compose and rgb to gray (on palette).
+ Fixes for C++ compilation using g++ When libpng source is compiled
+ using g++. The compiler imposes C++ rules on the C source; thus it
+ is desireable to make the source work with either C or C++ rules
+ without throwing away useful error information. This change adds
+ png_voidcast to allow C semantic (void*) cases or the corresponding
+ C++ static_cast operation, as appropriate.
+ Added --noexecstack to assembler file compilation. GCC does not set
+ this on assembler compilation, even though it does on C compilation.
+ This creates security issues if assembler code is enabled; the
+ work-around is to set it by default in the flags for $(CCAS)
+ Removed "zTXt" from warning in generic chunk decompression function.
+ 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.
+ Moved pngvalid.c into contrib/libtests
+ Rebuilt Makefile.in, configure, etc., with autoconf-2.68
+ Replaced an "#if" with "#ifdef" in pngrtran.c
+ Revised #if PNG_DO_BC block in png.c (use #ifdef and add #else)
+ Revised pngconf.h to use " __declspec(restrict)" only when MSC_VER >= 1400,
+ as in libpng-1.5.4.
+ Put CRLF line endings in the owatcom project files.
+ Updated CMakeLists.txt to account for the relocation of pngvalid.c
+ Minor fixes to pngvalid.c for gcc 4.6.2 compatibility to remove warnings
+ reported by earlier versions.