+Version 1.5.7beta01 [November 4, 2011]
+ 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.
+
+Version 1.5.7beta02 [November 11, 2011]
+ 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.
+ Updated scripts/pnglibconf.mak and scripts/makefile.std to handle the
+ new PNG_JOIN macro.
+ Added versioning to pnglibconf.h comments.
+ Simplified read/write API initial version; basic read/write tested on
+ a variety of images, limited documentation (in the header file.)
+ 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.
+
+Version 1.5.7beta03 [November 17, 2011]
+ Removed PNG_CONST from the sRGB table declarations in pngpriv.h and png.c
+ Added run-time detection of NEON support.
+ Added contrib/libtests; includes simplified API test and timing test and
+ a color conversion utility for rapid checking of failed 'pngstest' results.
+ 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 the simplified APIs themselves and to some bugs in compose and rgb to
+ gray (on palette) itself.
+ 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)
+ Work around compilers that don't support declaration of const data. Some
+ compilers fault 'extern const' data declarations (because the data is
+ not initialized); this turns on const-ness only for compilers where
+ this is known to work.
+
+Version 1.5.7beta04 [November 17, 2011]
+ Since the gcc driver does not recognize the --noexecstack flag, we must
+ use the -Wa prefix to have it passed through to the assembler.
+ Also removed a duplicate setting of this flag.
+ Added files that were omitted from the libpng-1.5.7beta03 zip distribution.
+
+Version 1.5.7beta05 [November 25, 2011]
+ 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.
+ Backed out 'simplified' API changes. The API seems too complex and there
+ is a lack of consensus or enthusiasm for the proposals. The API also
+ reveals significant bugs inside libpng (double gamma correction and the
+ known bug of being unable to retrieve a corrected palette). It seems
+ better to wait until the bugs, at least, are corrected.
+ Moved pngvalid.c into contrib/libtests
+ Rebuilt Makefile.in, configure, etc., with autoconf-2.68
+
+Version 1.5.7rc01 [December 1, 2011]
+ Replaced an "#if" with "#ifdef" in pngrtran.c
+ Revised #if PNG_DO_BC block in png.c (use #ifdef and add #else)
+
+Version 1.5.7rc02 [December 5, 2011]
+ Revised project files and contrib/pngvalid/pngvalid.c to account for
+ the relocation of pngvalid into contrib/libtests.
+ 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.
+
+Version 1.5.7rc03 [December 7, 2011]
+ Updated CMakeLists.txt to account for the relocation of pngvalid.c
+
+Version 1.5.7 [December 15, 2011]
+ Minor fixes to pngvalid.c for gcc 4.6.2 compatibility to remove warnings
+ reported by earlier versions.
+