Libpng 1.6.3 - July 18, 2013 This is a public release of libpng, intended for use in production codes. Files available for download: Source files with LF line endings (for Unix/Linux) and with a "configure" script libpng-1.6.3.tar.xz (LZMA-compressed, recommended) libpng-1.6.3.tar.gz Source files with CRLF line endings (for Windows), without the "configure" script lpng163.7z (LZMA-compressed, recommended) lpng163.zip Other information: libpng-1.6.3-README.txt libpng-1.6.3-LICENSE.txt Changes since the last public release (1.6.2): Revised stack marking in arm/filter_neon.S and configure.ac. Ensure that NEON filter stuff is completely disabled when switched 'off'. Previously the ARM NEON specific files were still built if the option was switched 'off' as opposed to being explicitly disabled. Test for 'arm*' not just 'arm' in the host_cpu configure variable. Rebuilt the configure scripts. Expanded manual paragraph about writing private chunks, particularly the need to call png_set_keep_unknown_chunks() when writing them. Avoid dereferencing NULL pointer possibly returned from png_create_write_struct() (Andrew Church). Calculate our own zlib windowBits when decoding rather than trusting the CMF bytes in the PNG datastream. Added an option to force maximum window size for inflating, which was the behavior of libpng15 and earlier. Added png-fix-itxt and png-fix-too-far-back to the built programs and removed warnings from the source code and timepng that are revealed as a result. Detect wrong libpng versions linked to png-fix-too-far-back, which currently only works with libpng versions that can be made to reliably fail when the deflate data contains an out-of-window reference. This means only 1.6 and later. Fixed gnu issues: g++ needs a static_cast, gcc 4.4.7 has a broken warning message which it is easier to work round than ignore. Updated contrib/pngminus/pnm2png.c (Paul Stewart): Check for EOF Ignore "#" delimited comments in input file to pnm2png.c. Fixed whitespace handling Added a call to png_set_packing() Initialize dimension values so if sscanf fails at least we have known invalid values. Attempt to detect configuration issues with png-fix-too-far-back, which requires both the correct libpng and the correct zlib to function correctly. Check ZLIB_VERNUM for mismatches, enclose #error in quotes Added information in the documentation about problems with and fixes for the bad CRC and bad iTXt chunk situations. Allow contrib/pngminus/pnm2png.c to compile without WRITE_INVERT and WRITE_PACK supported (writes error message that it can't read P1 or Improved png-fix-too-far-back usage message, added --suffix option. Revised contrib/pngminim/*/makefile to generate pnglibconf.h with the right zlib header files. Separated CPPFLAGS and CFLAGS in contrib/pngminim/*/makefile Removed a redundant test in png_set_IHDR(). Added set(CMAKE_CONFIGURATION_TYPES ...) to CMakeLists.txt (Andrew Hundt) Deleted set(CMAKE_BUILD_TYPE) block from CMakeLists.txt Enclose the prototypes for the simplified write API in #ifdef PNG_STDIO_SUPPORTED/#endif Make ARM NEON support work at compile time (not just configure time). This moves the test on __ARM_NEON__ into pngconf.h to avoid issues when using a compiler that compiles for multiple architectures at one time. Removed PNG_FILTER_OPTIMIZATIONS and PNG_ARM_NEON_SUPPORTED from 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. Protect symbol prefixing against CC/CPPFLAGS/CFLAGS useage. 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. Revised libpng.3 so that "doclifter" can process it. Revised example.c to illustrate use of PNG_DEFAULT_sRGB and PNG_GAMMA_MAC_18 as parameters for png_set_gamma(). These have been available since libpng-1.5.4. Renamed contrib/tools/png-fix-too-far-back.c to pngfix.c and revised it to check all compressed chunks known to libpng. Updated documentation to show default behavior of benign errors correctly. Only compile ARM code when PNG_READ_SUPPORTED is defined. Fixed undefined behavior in contrib/tools/pngfix.c and added new 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 Unified pngfix.c source with libpng17. Revised manual about changes in iTXt chunk handling made in libpng-1.6.0. Added "/* SAFE */" comments in pngrutil.c and pngrtran.c where warnings may be erroneously issued by code-checking applications. Send comments/corrections/commendations to png-mng-implement at lists.sf.net (subscription required; visit https://lists.sourceforge.net/lists/listinfo/png-mng-implement to subscribe) or to glennrp at users.sourceforge.net Glenn R-P