Libpng-1.5.5 is available from
Changes since the last public release (1.5.4):
Fixed some typos and made other minor changes in the manual.
Updated contrib/pngminus/makefile.std (Samuli Souminen)
Revised Makefile.am and Makefile.in to look in the right directory for
Enabled compilation with g++ compiler. This compiler does not recognize
the file extension, so it always compiles with C++ rules. Made minor
changes to pngrutil.c to cast results where C++ expects it but C does not.
Minor editing of libpng.3 and libpng-manual.txt.
Revised CMakeLists.txt (Clifford Yapp)
Updated commentary about the png_rgb_to_gray() default coefficients
in the manual and in pngrtran.c
Prevent unexpected API exports from non-libpng DLLs on Windows. The "_DLL"
is removed from the test of whether a DLL is being built (this erroneously
caused the libpng APIs to be marked as DLL exports in static builds under
Microsoft Visual Studio). Almost all of the libpng building configuration
is moved from pngconf.h to pngpriv.h, but PNG_DLL_EXPORT remains in
pngconf.h, though, so that it is colocated with the import definition (it
is no longer used anywhere in the installed headers). The VStudio project
definitions have been cleaned up: "_USRDLL" has been removed from the
static library builds (this was incorrect), and PNG_USE_DLL has been added
to pngvalid to test the functionality (pngtest does not supply it,
deliberately). The spurious "_EXPORTS" has been removed from the
libpng build (all these errors were a result of copy/paste between project
Added new types and internal functions for CIE RGB end point handling to
pngpriv.h (functions yet to be implemented).
Ensure the CMAKE_LIBRARY_OUTPUT_DIRECTORY is set in CMakeLists.txt
Fixes to rgb_to_gray and cHRM XYZ APIs (John Bowler):
The rgb_to_gray code had errors when combined with gamma correction.
Some pixels were treated as true grey when they weren't and such pixels
and true grey ones were not gamma corrected (the original value of the
red component was used instead). APIs to get and set cHRM using color
space end points have been added and the rgb_to_gray code that defaults
based on cHRM, and the divide-by-zero bug in png_handle_cHRM (CERT
VU#477046, CVE-2011-3328, introduced in 1.5.4) have been corrected.
A considerable number of tests has been added to pngvalid for the
Arithmetic errors in rgb_to_gray whereby the calculated gray value was
truncated to the bit depth rather than rounded have been fixed except in
the 8-bit non-gamma-corrected case (where consistency seems more important
than correctness.) The code still has considerable inaccuracies in the
8-bit case because 8-bit linear arithmetic is used.
Added "$(ARCH)" option to makefile.darwin
Added SunOS support to configure.ac and Makefile.am
Changed png_chunk_benign_error() to png_warning() in png.c, in
Fixed 64-bit compilation errors (gcc). The errors fixed relate
to conditions where types that are 32 bits in the GCC 32-bit
world (uLong and png_size_t) become 64 bits in the 64-bit
world. This produces potential truncation errors that the
compiler correctly flags.
Constant changes for 64-bit compatibility (removal of L suffixes). The
16-bit cases still use "L" as we don't have a 16-bit test system.