+Version 0.2
+ added reader into png.h
+ fixed small problems in stub file
+
+Version 0.3
+ added pull reader
+ split up pngwrite.c to several files
+ added pnglib.txt
+ added example.c
+ cleaned up writer, adding a few new transformations
+ fixed some bugs in writer
+ interfaced with zlib 0.5
+ added K&R support
+ added check for 64 KB blocks for 16-bit machines
+
+Version 0.4
+ cleaned up code and commented code
+ simplified time handling into png_time
+ created png_color_16 and png_color_8 to handle color needs
+ cleaned up color type defines
+ fixed various bugs
+ made various names more consistent
+ interfaced with zlib 0.71
+ cleaned up zTXt reader and writer (using zlib's Reset functions)
+ split transformations into pngrtran.c and pngwtran.c
+
+Version 0.5
+ interfaced with zlib 0.8
+ fixed many reading and writing bugs
+ saved using 3 spaces instead of tabs
+
+Version 0.6
+ added png_large_malloc() and png_large_free()
+ added png_size_t
+ cleaned up some compiler warnings
+ added png_start_read_image()
+
+Version 0.7
+ cleaned up lots of bugs
+ finished dithering and other stuff
+ added test program
+ changed name from pnglib to libpng
+
+Version 0.71 [June, 1995]
+ changed pngtest.png for zlib 0.93
+ fixed error in libpng.txt and example.c
+
+Version 0.8
+ cleaned up some bugs
+ added png_set_filler()
+ split up pngstub.c into pngmem.c, pngio.c, and pngerror.c
+ added #define's to remove unwanted code
+ moved png_info_init() to png.c
+ added old_size into png_realloc()
+ added functions to manually set filtering and compression info
+ changed compression parameters based on image type
+ optimized filter selection code
+ added version info
+ changed external functions passing floats to doubles (k&r problems?)
+ put all the configurable stuff in pngconf.h
+ enabled png_set_shift to work with paletted images on read
+ added png_read_update_info() - updates info structure with transformations
+
+Version 0.81 [August, 1995]
+ incorporated Tim Wegner's medium model code (thanks, Tim)
+
+Version 0.82 [September, 1995]
+ [unspecified changes]
+
+Version 0.85 [December, 1995]
+ added more medium model code (almost everything's a far)
+ added i/o, error, and memory callback functions
+ fixed some bugs (16-bit, 4-bit interlaced, etc.)
+ added first run progressive reader (barely tested)
+
+Version 0.86 [January, 1996]
+ fixed bugs
+ improved documentation
+
+Version 0.87 [January, 1996]
+ fixed medium model bugs
+ fixed other bugs introduced in 0.85 and 0.86
+ added some minor documentation
+
+Version 0.88 [January, 1996]
+ fixed progressive bugs
+ replaced tabs with spaces
+ cleaned up documentation
+ added callbacks for read/write and warning/error functions
+
+Version 0.89 [July, 1996]
+ Added new initialization API to make libpng work better with shared libs
+ we now have png_create_read_struct(), png_create_write_struct(),
+ png_create_info_struct(), png_destroy_read_struct(), and
+ png_destroy_write_struct() instead of the separate calls to
+ malloc and png_read_init(), png_info_init(), and png_write_init()
+ Changed warning/error callback functions to fix bug - this means you
+ should use the new initialization API if you were using the old
+ png_set_message_fn() calls, and that the old API no longer exists
+ so that people are aware that they need to change their code
+ Changed filter selection API to allow selection of multiple filters
+ since it didn't work in previous versions of libpng anyways
+ Optimized filter selection code
+ Fixed png_set_background() to allow using an arbitrary RGB color for
+ paletted images
+ Fixed gamma and background correction for paletted images, so
+ png_correct_palette is not needed unless you are correcting an
+ external palette (you will need to #define PNG_CORRECT_PALETTE_SUPPORTED
+ in pngconf.h) - if nobody uses this, it may disappear in the future.
+ Fixed bug with Borland 64K memory allocation (Alexander Lehmann)
+ Fixed bug in interlace handling (Smarasderagd, I think)
+ Added more error checking for writing and image to reduce invalid files
+ Separated read and write functions so that they won't both be linked
+ into a binary when only reading or writing functionality is used
+ New pngtest image also has interlacing and zTXt
+ Updated documentation to reflect new API
+
+Version 0.90 [January, 1997]
+ Made CRC errors/warnings on critical and ancillary chunks configurable
+ libpng will use the zlib CRC routines by (compile-time) default
+ Changed DOS small/medium model memory support - needs zlib 1.04 (Tim Wegner)
+ Added external C++ wrapper statements to png.h (Gilles Dauphin)
+ Allow PNG file to be read when some or all of file signature has already
+ been read from the beginning of the stream. ****This affects the size
+ of info_struct and invalidates all programs that use a shared libpng****
+ Fixed png_filler() declarations
+ Fixed? background color conversions
+ Fixed order of error function pointers to match documentation
+ Current chunk name is now available in png_struct to reduce the number
+ of nearly identical error messages (will simplify multi-lingual
+ support when available)
+ Try to get ready for unknown-chunk callback functions:
+ - previously read critical chunks are flagged, so the chunk handling
+ routines can determine if the chunk is in the right place
+ - all chunk handling routines have the same prototypes, so we will
+ be able to handle all chunks via a callback mechanism
+ Try to fix Linux "setjmp" buffer size problems
+ Removed png_large_malloc, png_large_free, and png_realloc functions.
+
+Version 0.95 [March, 1997]
+ Fixed bug in pngwutil.c allocating "up_row" twice and "avg_row" never
+ Fixed bug in PNG file signature compares when start != 0
+ Changed parameter type of png_set_filler(...filler...) from png_byte
+ to png_uint_32
+ Added test for MACOS to ensure that both math.h and fp.h are not #included
+ Added macros for libpng to be compiled as a Windows DLL (Andreas Kupries)
+ Added "packswap" transformation, which changes the endianness of
+ packed-pixel bytes (Kevin Bracey)
+ Added "strip_alpha" transformation, which removes the alpha channel of
+ input images without using it (not necessarily a good idea)
+ Added "swap_alpha" transformation, which puts the alpha channel in front
+ of the color bytes instead of after
+ Removed all implicit variable tests which assume NULL == 0 (I think)
+ Changed several variables to "png_size_t" to show 16/32-bit limitations
+ Added new pCAL chunk read/write support
+ Added experimental filter selection weighting (Greg Roelofs)
+ Removed old png_set_rgbx() and png_set_xrgb() functions that have been
+ obsolete for about 2 years now (use png_set_filler() instead)
+ Added macros to read 16- and 32-bit ints directly from buffer, to be
+ used only on those systems that support it (namely PowerPC and 680x0)
+ With some testing, this may become the default for MACOS/PPC systems.
+ Only calculate CRC on data if we are going to use it
+ Added macros for zTXt compression type PNG_zTXt_COMPRESSION_???
+ Added macros for simple libpng debugging output selectable at compile time
+ Removed PNG_READ_END_MODE in progressive reader (Smarasderagd)
+ More description of info_struct in libpng.txt and png.h
+ More instructions in example.c
+ More chunk types tested in pngtest.c
+ Renamed pngrcb.c to pngset.c, and all png_read_<chunk> functions to be
+ png_set_<chunk>. We now have corresponding png_get_<chunk>
+ functions in pngget.c to get information in info_ptr. This isolates
+ the application from the internal organization of png_info_struct
+ (good for shared library implementations).
+
+Version 0.96 [May, 1997]
+ Fixed serious bug with < 8bpp images introduced in 0.95
+ Fixed 256-color transparency bug (Greg Roelofs)
+ Fixed up documentation (Greg Roelofs, Laszlo Nyul)
+ Fixed "error" in pngconf.h for Linux setjmp() behavior
+ Fixed DOS medium model support (Tim Wegner)
+ Fixed png_check_keyword() for case with error in static string text
+ Added read of CRC after IEND chunk for embedded PNGs (Laszlo Nyul)
+ Added typecasts to quiet compiler errors
+ Added more debugging info
+
+Version 0.97 [January, 1998]
+ Removed PNG_USE_OWN_CRC capability
+ Relocated png_set_crc_action from pngrutil.c to pngrtran.c
+ Fixed typecasts of "new_key", etc. (Andreas Dilger)
+ Added RFC 1152 [sic] date support
+ Fixed bug in gamma handling of 4-bit grayscale
+ Added 2-bit grayscale gamma handling (Glenn R-P)
+ Added more typecasts. 65536L becomes (png_uint_32)65536L, etc. (Glenn R-P)
+ Minor corrections in libpng.txt
+ Added simple sRGB support (Glenn R-P)
+ Easier conditional compiling, e.g.,
+ define PNG_READ/WRITE_NOT_FULLY_SUPPORTED;
+ all configurable options can be selected from command-line instead
+ of having to edit pngconf.h (Glenn R-P)
+ Fixed memory leak in pngwrite.c (free info_ptr->text) (Glenn R-P)
+ Added more conditions for png_do_background, to avoid changing
+ black pixels to background when a background is supplied and
+ no pixels are transparent
+ Repaired PNG_NO_STDIO behavior
+ Tested NODIV support and made it default behavior (Greg Roelofs)
+ Added "-m" option and PNGTEST_DEBUG_MEMORY to pngtest (John Bowler)
+ Regularized version numbering scheme and bumped shared-library major
+ version number to 2 to avoid problems with libpng 0.89 apps
+ (Greg Roelofs)
+
+Version 0.98 [January, 1998]
+ Cleaned up some typos in libpng.txt and in code documentation
+ Fixed memory leaks in pCAL chunk processing (Glenn R-P and John Bowler)
+ Cosmetic change "display_gamma" to "screen_gamma" in pngrtran.c
+ Changed recommendation about file_gamma for PC images to .51 from .45,
+ in example.c and libpng.txt, added comments to distinguish between
+ screen_gamma, viewing_gamma, and display_gamma.
+ Changed all references to RFC1152 to read RFC1123 and changed the
+ PNG_TIME_RFC1152_SUPPORTED macro to PNG_TIME_RFC1123_SUPPORTED
+ Added png_invert_alpha capability (Glenn R-P -- suggestion by Jon Vincent)
+ Changed srgb_intent from png_byte to int to avoid compiler bugs
+
+Version 0.99 [January 30, 1998]
+ Free info_ptr->text instead of end_info_ptr->text in pngread.c (John Bowler)
+ Fixed a longstanding "packswap" bug in pngtrans.c
+ Fixed some inconsistencies in pngconf.h that prevented compiling with
+ PNG_READ_GAMMA_SUPPORTED and PNG_READ_hIST_SUPPORTED undefined
+ Fixed some typos and made other minor rearrangement of libpng.txt (Andreas)
+ Changed recommendation about file_gamma for PC images to .50 from .51 in
+ example.c and libpng.txt, and changed file_gamma for sRGB images to .45
+ Added a number of functions to access information from the png structure
+ png_get_image_height(), etc. (Glenn R-P, suggestion by Brad Pettit)
+ Added TARGET_MACOS similar to zlib-1.0.8
+ Define PNG_ALWAYS_EXTERN when __MWERKS__ && WIN32 are defined
+ Added type casting to all png_malloc() function calls
+
+Version 0.99a [January 31, 1998]
+ Added type casts and parentheses to all returns that return a value.(Tim W.)
+
+Version 0.99b [February 4, 1998]
+ Added type cast png_uint_32 on malloc function calls where needed.
+ Changed type of num_hist from png_uint_32 to int (same as num_palette).
+ Added checks for rowbytes overflow, in case png_size_t is less than 32 bits.
+ Renamed makefile.elf to makefile.lnx.
+
+Version 0.99c [February 7, 1998]
+ More type casting. Removed erroneous overflow test in pngmem.c.
+ Added png_buffered_memcpy() and png_buffered_memset(), apply them to rowbytes.
+ Added UNIX manual pages libpng.3 (incorporating libpng.txt) and png.5.
+
+Version 0.99d [February 11, 1998]
+ Renamed "far_to_near()" "png_far_to_near()"
+ Revised libpng.3
+ Version 99c "buffered" operations didn't work as intended. Replaced them
+ with png_memcpy_check() and png_memset_check().
+ Added many "if (png_ptr == NULL) return" to quell compiler warnings about
+ unused png_ptr, mostly in pngget.c and pngset.c.
+ Check for overlength tRNS chunk present when indexed-color PLTE is read.
+ Cleaned up spelling errors in libpng.3/libpng.txt
+ Corrected a problem with png_get_tRNS() which returned undefined trans array
+
+Version 0.99e [February 28, 1998]
+ Corrected png_get_tRNS() again.
+ Add parentheses for easier reading of pngget.c, fixed "||" should be "&&".
+ Touched up example.c to make more of it compileable, although the entire
+ file still can't be compiled (Willem van Schaik)
+ Fixed a bug in png_do_shift() (Bryan Tsai)
+ Added a space in png.h prototype for png_write_chunk_start()
+ Replaced pngtest.png with one created with zlib 1.1.1
+ Changed pngtest to report PASS even when file size is different (Jean-loup G.)
+ Corrected some logic errors in png_do_invert_alpha() (Chris Patterson)
+
+Version 0.99f [March 5, 1998]
+ Corrected a bug in pngpread() introduced in version 99c (Kevin Bracey)
+ Moved makefiles into a "scripts" directory, and added INSTALL instruction file
+ Added makefile.os2 and pngos2.def (A. Zabolotny) and makefile.s2x (W. Sebok)
+ Added pointers to "note on libpng versions" in makefile.lnx and README
+ Added row callback feature when reading and writing nonprogressive rows
+ and added a test of this feature in pngtest.c
+ Added user transform callbacks, with test of the feature in pngtest.c
+
+Version 0.99g [March 6, 1998, morning]
+ Minor changes to pngtest.c to suppress compiler warnings.
+ Removed "beta" language from documentation.
+
+Version 0.99h [March 6, 1998, evening]
+ Minor changes to previous minor changes to pngtest.c
+ Changed PNG_READ_NOT_FULLY_SUPPORTED to PNG_READ_TRANSFORMS_NOT_SUPPORTED
+ and added PNG_PROGRESSIVE_READ_NOT_SUPPORTED macro
+ Added user transform capability
+
+Version 1.00 [March 7, 1998]
+ Changed several typedefs in pngrutil.c
+ Added makefile.wat (Pawel Mrochen), updated makefile.tc3 (Willem van Schaik)
+ Replaced "while(1)" with "for(;;)"
+ Added PNGARG() to prototypes in pngtest.c and removed some prototypes
+ Updated some of the makefiles (Tom Lane)
+ Changed some typedefs (s_start, etc.) in pngrutil.c
+ Fixed dimensions of "short_months" array in pngwrite.c
+ Replaced ansi2knr.c with the one from jpeg-v6
+
+Version 1.0.0 [March 8, 1998]
+ Changed name from 1.00 to 1.0.0 (Adam Costello)
+ Added smakefile.ppc (with SCOPTIONS.ppc) for Amiga PPC (Andreas Kleinert)
+
+Version 1.0.0a [March 9, 1998]
+ Fixed three bugs in pngrtran.c to make gamma+background handling consistent
+ (Greg Roelofs)
+ Changed format of the PNG_LIBPNG_VER integer to xyyzz instead of xyz
+ for major, minor, and bugfix releases. This is 10001. (Adam Costello,
+ Tom Lane)
+ Make months range from 1-12 in png_convert_to_rfc1123
+
+Version 1.0.0b [March 13, 1998]
+ Quieted compiler complaints about two empty "for" loops in pngrutil.c
+ Minor changes to makefile.s2x
+ Removed #ifdef/#endif around a png_free() in pngread.c
+
+Version 1.0.1 [March 14, 1998]
+ Changed makefile.s2x to reduce security risk of using a relative pathname
+ Fixed some typos in the documentation (Greg).
+ Fixed a problem with value of "channels" returned by png_read_update_info()
+
+Version 1.0.1a [April 21, 1998]
+ Optimized Paeth calculations by replacing abs() function calls with intrinsics
+ plus other loop optimizations. Improves avg decoding speed by about 20%.
+ Commented out i386istic "align" compiler flags in makefile.lnx.
+ Reduced the default warning level in some makefiles, to make them consistent.
+ Removed references to IJG and JPEG in the ansi2knr.c copyright statement.
+ Fixed a bug in png_do_strip_filler with XXRRGGBB => RRGGBB transformation.
+ Added grayscale and 16-bit capability to png_do_read_filler().
+ Fixed a bug in pngset.c, introduced in version 0.99c, that sets rowbytes
+ too large when writing an image with bit_depth < 8 (Bob Dellaca).
+ Corrected some bugs in the experimental weighted filtering heuristics.
+ Moved a misplaced pngrutil code block that truncates tRNS if it has more
+ than num_palette entries -- test was done before num_palette was defined.
+ Fixed a png_convert_to_rfc1123() bug that converts day 31 to 0 (Steve Eddins).
+ Changed compiler flags in makefile.wat for better optimization
+ (Pawel Mrochen).
+
+Version 1.0.1b [May 2, 1998]
+ Relocated png_do_gray_to_rgb() within png_do_read_transformations() (Greg).
+ Relocated the png_composite macros from pngrtran.c to png.h (Greg).
+ Added makefile.sco (contributed by Mike Hopkirk).
+ Fixed two bugs (missing definitions of "istop") introduced in libpng-1.0.1a.
+ Fixed a bug in pngrtran.c that would set channels=5 under some circumstances.
+ More work on the Paeth-filtering, achieving imperceptible speedup
+ (A Kleinert).
+ More work on loop optimization which may help when compiled with C++
+ compilers.
+ Added warnings when people try to use transforms they've defined out.
+ Collapsed 4 "i" and "c" loops into single "i" loops in pngrtran and pngwtran.
+ Revised paragraph about png_set_expand() in libpng.txt and libpng.3 (Greg)
+
+Version 1.0.1c [May 11, 1998]
+ Fixed a bug in pngrtran.c (introduced in libpng-1.0.1a) where the masks for
+ filler bytes should have been 0xff instead of 0xf.
+ Added max_pixel_depth=32 in pngrutil.c when using FILLER with palette images.
+ Moved PNG_WRITE_WEIGHTED_FILTER_SUPPORTED and PNG_WRITE_FLUSH_SUPPORTED
+ out of the PNG_WRITE_TRANSFORMS_NOT_SUPPORTED block of pngconf.h
+ Added "PNG_NO_WRITE_TRANSFORMS" etc., as alternatives for *_NOT_SUPPORTED,
+ for consistency, in pngconf.h
+ Added individual "ifndef PNG_NO_[CAPABILITY]" in pngconf.h to make it easier
+ to remove unwanted capabilities via the compile line
+ Made some corrections to grammar (which, it's) in documentation (Greg).
+ Corrected example.c, use of row_pointers in png_write_image().
+
+Version 1.0.1d [May 24, 1998]
+ Corrected several statements that used side effects illegally in pngrutil.c
+ and pngtrans.c, that were introduced in version 1.0.1b
+ Revised png_read_rows() to avoid repeated if-testing for NULL (A Kleinert)
+ More corrections to example.c, use of row_pointers in png_write_image()
+ and png_read_rows().
+ Added pngdll.mak and pngdef.pas to scripts directory, contributed by
+ Bob Dellaca, to make a png32bd.dll with Borland C++ 4.5
+ Fixed error in example.c with png_set_text: num_text is 3, not 2 (Guido V.)
+ Changed several loops from count-down to count-up, for consistency.
+
+Version 1.0.1e [June 6, 1998]
+ Revised libpng.txt and libpng.3 description of png_set_read|write_fn(), and
+ added warnings when people try to set png_read_fn and png_write_fn in
+ the same structure.
+ Added a test such that png_do_gamma will be done when num_trans==0
+ for truecolor images that have defined a background. This corrects an
+ error that was introduced in libpng-0.90 that can cause gamma processing
+ to be skipped.
+ Added tests in png.h to include "trans" and "trans_values" in structures
+ when PNG_READ_BACKGROUND_SUPPORTED or PNG_READ_EXPAND_SUPPORTED is defined.
+ Add png_free(png_ptr->time_buffer) in png_destroy_read_struct()
+ Moved png_convert_to_rfc_1123() from pngwrite.c to png.c
+ Added capability for user-provided malloc_fn() and free_fn() functions,
+ and revised pngtest.c to demonstrate their use, replacing the
+ PNGTEST_DEBUG_MEM feature.
+ Added makefile.w32, for Microsoft C++ 4.0 and later (Tim Wegner).
+
+Version 1.0.2 [June 14, 1998]
+ Fixed two bugs in makefile.bor .
+
+Version 1.0.2a [December 30, 1998]
+ Replaced and extended code that was removed from png_set_filler() in 1.0.1a.
+ Fixed a bug in png_do_filler() that made it fail to write filler bytes in
+ the left-most pixel of each row (Kevin Bracey).
+ Changed "static pngcharp tIME_string" to "static char tIME_string[30]"
+ in pngtest.c (Duncan Simpson).
+ Fixed a bug in pngtest.c that caused pngtest to try to write a tIME chunk
+ even when no tIME chunk was present in the source file.
+ Fixed a problem in pngrutil.c: gray_to_rgb didn't always work with 16-bit.
+ Fixed a problem in png_read_push_finish_row(), which would not skip some
+ passes that it should skip, for images that are less than 3 pixels high.
+ Interchanged the order of calls to png_do_swap() and png_do_shift()
+ in pngwtran.c (John Cromer).
+ Added #ifdef PNG_DEBUG/#endif surrounding use of PNG_DEBUG in png.h .
+ Changed "bad adaptive filter type" from error to warning in pngrutil.c .
+ Fixed a documentation error about default filtering with 8-bit indexed-color.
+ Separated the PNG_NO_STDIO macro into PNG_NO_STDIO and PNG_NO_CONSOLE_IO
+ (L. Peter Deutsch).
+ Added png_set_rgb_to_gray() and png_get_rgb_to_gray_status() functions.
+ Added png_get_copyright() and png_get_header_version() functions.
+ Revised comments on png_set_progressive_read_fn() in libpng.txt and example.c
+ Added information about debugging in libpng.txt and libpng.3 .
+ Changed "ln -sf" to "ln -s -f" in makefile.s2x, makefile.lnx, and
+ makefile.sco.
+ Removed lines after Dynamic Dependencies" in makefile.aco .
+ Revised makefile.dec to make a shared library (Jeremie Petit).
+ Removed trailing blanks from all files.
+
+Version 1.0.2a [January 6, 1999]
+ Removed misplaced #endif and #ifdef PNG_NO_EXTERN near the end of png.h
+ Added "if" tests to silence complaints about unused png_ptr in png.h and png.c
+ Changed "check_if_png" function in example.c to return true (nonzero) if PNG.
+ Changed libpng.txt to demonstrate png_sig_cmp() instead of png_check_sig()
+ which is obsolete.
+
+Version 1.0.3 [January 14, 1999]
+ Added makefile.hux, for Hewlett Packard HPUX 10.20 and 11.00 (Jim Rice)
+ Added a statement of Y2K compliance in png.h, libpng.3, and Y2KINFO.
+
+Version 1.0.3a [August 12, 1999]
+ Added check for PNG_READ_INTERLACE_SUPPORTED in pngread.c; issue a warning
+ if an attempt is made to read an interlaced image when it's not supported.
+ Added check if png_ptr->trans is defined before freeing it in pngread.c
+ Modified the Y2K statement to include versions back to version 0.71
+ Fixed a bug in the check for valid IHDR bit_depth/color_types in pngrutil.c
+ Modified makefile.wat (added -zp8 flag, ".symbolic", changed some comments)
+ Replaced leading blanks with tab characters in makefile.hux
+ Changed "dworkin.wustl.edu" to "ccrc.wustl.edu" in various documents.
+ Changed (float)red and (float)green to (double)red, (double)green
+ in png_set_rgb_to_gray() to avoid "promotion" problems in AIX.
+ Fixed a bug in pngconf.h that omitted <stdio.h> when PNG_DEBUG==0 (K Bracey).
+ Reformatted libpng.3 and libpngpf.3 with proper fonts (script by J. vanZandt).
+ Updated documentation to refer to the PNG-1.2 specification.
+ Removed ansi2knr.c and left pointers to the latest source for ansi2knr.c
+ in makefile.knr, INSTALL, and README (L. Peter Deutsch)
+ Fixed bugs in calculation of the length of rowbytes when adding alpha
+ channels to 16-bit images, in pngrtran.c (Chris Nokleberg)
+ Added function png_set_user_transform_info() to store user_transform_ptr,
+ user_depth, and user_channels into the png_struct, and a function
+ png_get_user_transform_ptr() to retrieve the pointer (Chris Nokleberg)
+ Added function png_set_empty_plte_permitted() to make libpng useable
+ in MNG applications.
+ Corrected the typedef for png_free_ptr in png.h (Jesse Jones).
+ Correct gamma with srgb is 45455 instead of 45000 in pngrutil.c, to be
+ consistent with PNG-1.2, and allow variance of 500 before complaining.
+ Added assembler code contributed by Intel in file pngvcrd.c and modified
+ makefile.w32 to use it (Nirav Chhatrapati, INTEL Corporation,
+ Gilles Vollant)
+ Changed "ln -s -f" to "ln -f -s" in the makefiles to make Solaris happy.
+ Added some aliases for png_set_expand() in pngrtran.c, namely
+ png_set_expand_PLTE(), png_set_expand_depth(), and png_set_expand_tRNS()
+ (Greg Roelofs, in "PNG: The Definitive Guide").
+ Added makefile.beo for BEOS on X86, contributed by Sander Stok.
+
+Version 1.0.3b [August 26, 1999]
+ Replaced 2147483647L several places with PNG_MAX_UINT macro, defined in png.h
+ Changed leading blanks to tabs in all makefiles.
+ Define PNG_USE_PNGVCRD in makefile.w32, to get MMX assembler code.
+ Made alternate versions of png_set_expand() in pngrtran.c, namely
+ png_set_gray_1_2_4_to_8, png_set_palette_to_rgb, and png_set_tRNS_to_alpha
+ (Greg Roelofs, in "PNG: The Definitive Guide"). Deleted the 1.0.3a aliases.
+ Relocated start of 'extern "C"' block in png.h so it doesn't include pngconf.h
+ Revised calculation of num_blocks in pngmem.c to avoid a potentially
+ negative shift distance, whose results are undefined in the C language.
+ Added a check in pngset.c to prevent writing multiple tIME chunks.
+ Added a check in pngwrite.c to detect invalid small window_bits sizes.
+
+Version 1.0.3d [September 4, 1999]
+ Fixed type casting of igamma in pngrutil.c
+ Added new png_expand functions to scripts/pngdef.pas and pngos2.def
+ Added a demo read_user_transform_fn that examines the row filters in pngtest.c
+
+Version 1.0.4 [September 24, 1999]
+ Define PNG_ALWAYS_EXTERN in pngconf.h if __STDC__ is defined
+ Delete #define PNG_INTERNAL and include "png.h" from pngasmrd.h
+ Made several minor corrections to pngtest.c
+ Renamed the makefiles with longer but more user friendly extensions.
+ Copied the PNG copyright and license to a separate LICENSE file.
+ Revised documentation, png.h, and example.c to remove reference to
+ "viewing_gamma" which no longer appears in the PNG specification.
+ Revised pngvcrd.c to use MMX code for interlacing only on the final pass.
+ Updated pngvcrd.c to use the faster C filter algorithms from libpng-1.0.1a
+ Split makefile.win32vc into two versions, makefile.vcawin32 (uses MMX
+ assembler code) and makefile.vcwin32 (doesn't).
+ Added a CPU timing report to pngtest.c (enabled by defining PNGTEST_TIMING)
+ Added a copy of pngnow.png to the distribution.
+
+Version 1.0.4a [September 25, 1999]
+ Increase max_pixel_depth in pngrutil.c if a user transform needs it.
+ Changed several division operations to right-shifts in pngvcrd.c
+
+Version 1.0.4b [September 30, 1999]
+ Added parentheses in line 3732 of pngvcrd.c
+ Added a comment in makefile.linux warning about buggy -O3 in pgcc 2.95.1
+
+Version 1.0.4c [October 1, 1999]
+ Added a "png_check_version" function in png.c and pngtest.c that will generate
+ a helpful compiler error if an old png.h is found in the search path.
+ Changed type of png_user_transform_depth|channels from int to png_byte.
+
+Version 1.0.4d [October 6, 1999]
+ Changed 0.45 to 0.45455 in png_set_sRGB()
+ Removed unused PLTE entries from pngnow.png
+ Re-enabled some parts of pngvcrd.c (png_combine_row) that work properly.
+
+Version 1.0.4e [October 10, 1999]
+ Fixed sign error in pngvcrd.c (Greg Roelofs)
+ Replaced some instances of memcpy with simple assignments in pngvcrd (GR-P)
+
+Version 1.0.4f [October 15, 1999]
+ Surrounded example.c code with #if 0 .. #endif to prevent people from
+ inadvertently trying to compile it.
+ Changed png_get_header_version() from a function to a macro in png.h
+ Added type casting mostly in pngrtran.c and pngwtran.c
+ Removed some pointless "ptr = NULL" in pngmem.c
+ Added a "contrib" directory containing the source code from Greg's book.
+
+Version 1.0.5 [October 15, 1999]
+ Minor editing of the INSTALL and README files.
+
+Version 1.0.5a [October 23, 1999]
+ Added contrib/pngsuite and contrib/pngminus (Willem van Schaik)
+ Fixed a typo in the png_set_sRGB() function call in example.c (Jan Nijtmans)
+ Further optimization and bugfix of pngvcrd.c
+ Revised pngset.c so that it does not allocate or free memory in the user's
+ text_ptr structure. Instead, it makes its own copy.
+ Created separate write_end_info_struct in pngtest.c for a more severe test.
+ Added code in pngwrite.c to free info_ptr->text[i].key to stop a memory leak.
+
+Version 1.0.5b [November 23, 1999]
+ Moved PNG_FLAG_HAVE_CHUNK_HEADER, PNG_FLAG_BACKGROUND_IS_GRAY and
+ PNG_FLAG_WROTE_tIME from flags to mode.
+ Added png_write_info_before_PLTE() function.
+ Fixed some typecasting in contrib/gregbook/*.c
+ Updated scripts/makevms.com and added makevms.com to contrib/gregbook
+ and contrib/pngminus (Martin Zinser)
+
+Version 1.0.5c [November 26, 1999]
+ Moved png_get_header_version from png.h to png.c, to accommodate ansi2knr.
+ Removed all global arrays (according to PNG_NO_GLOBAL_ARRAYS macro), to
+ accommodate making DLL's: Moved usr_png_ver from global variable to function
+ png_get_header_ver() in png.c. Moved png_sig to png_sig_bytes in png.c and
+ eliminated use of png_sig in pngwutil.c. Moved the various png_CHNK arrays
+ into pngtypes.h. Eliminated use of global png_pass arrays. Declared the
+ png_CHNK and png_pass arrays to be "const". Made the global arrays
+ available to applications (although none are used in libpng itself) when
+ PNG_NO_GLOBAL_ARRAYS is not defined or when PNG_GLOBAL_ARRAYS is defined.
+ Removed some extraneous "-I" from contrib/pngminus/makefile.std
+ Changed the PNG_sRGB_INTENT macros in png.h to be consistent with PNG-1.2.
+ Change PNG_SRGB_INTENT to PNG_sRGB_INTENT in libpng.txt and libpng.3
+
+Version 1.0.5d [November 29, 1999]
+ Add type cast (png_const_charp) two places in png.c
+ Eliminated pngtypes.h; use macros instead to declare PNG_CHNK arrays.
+ Renamed "PNG_GLOBAL_ARRAYS" to "PNG_USE_GLOBAL_ARRAYS" and made available
+ to applications a macro "PNG_USE_LOCAL_ARRAYS".
+ comment out (with #ifdef) all the new declarations when
+ PNG_USE_GLOBAL_ARRAYS is defined.
+ Added PNG_EXPORT_VAR macro to accommodate making DLL's.
+
+Version 1.0.5e [November 30, 1999]
+ Added iCCP, iTXt, and sPLT support; added "lang" member to the png_text
+ structure; refactored the inflate/deflate support to make adding new chunks
+ with trailing compressed parts easier in the future, and added new functions
+ png_free_iCCP, png_free_pCAL, png_free_sPLT, png_free_text, png_get_iCCP,
+ png_get_spalettes, png_set_iCCP, png_set_spalettes (Eric S. Raymond).
+ NOTE: Applications that write text chunks MUST define png_text->lang
+ before calling png_set_text(). It must be set to NULL if you want to
+ write tEXt or zTXt chunks. If you want your application to be able to
+ run with older versions of libpng, use
+
+ #ifdef PNG_iTXt_SUPPORTED
+ png_text[i].lang = NULL;
+ #endif
+
+ Changed png_get_oFFs() and png_set_oFFs() to use signed rather than unsigned
+ offsets (Eric S. Raymond).
+ Combined PNG_READ_cHNK_SUPPORTED and PNG_WRITE_cHNK_SUPPORTED macros into
+ PNG_cHNK_SUPPORTED and combined the three types of PNG_text_SUPPORTED
+ macros, leaving the separate macros also available.
+ Removed comments on #endifs at the end of many short, non-nested #if-blocks.
+
+Version 1.0.5f [December 6, 1999]
+ Changed makefile.solaris to issue a warning about potential problems when
+ the ucb "ld" is in the path ahead of the ccs "ld".
+ Removed "- [date]" from the "synopsis" line in libpng.3 and libpngpf.3.
+ Added sCAL chunk support (Eric S. Raymond).
+
+Version 1.0.5g [December 7, 1999]
+ Fixed "png_free_spallettes" typo in png.h
+ Added code to handle new chunks in pngpread.c
+ Moved PNG_CHNK string macro definitions outside of PNG_NO_EXTERN block
+ Added "translated_key" to png_text structure and png_write_iTXt().
+ Added code in pngwrite.c to work around a newly discovered zlib bug.
+
+Version 1.0.5h [December 10, 1999]
+ NOTE: regarding the note for version 1.0.5e, the following must also
+ be included in your code:
+ png_text[i].translated_key = NULL;
+ Unknown chunk handling is now supported.
+ Option to eliminate all floating point support was added. Some new
+ fixed-point functions such as png_set_gAMA_fixed() were added.
+ Expanded tabs and removed trailing blanks in source files.
+
+Version 1.0.5i [December 13, 1999]
+ Added some type casts to silence compiler warnings.
+ Renamed "png_free_spalette" to "png_free_spalettes" for consistency.
+ Removed leading blanks from a #define in pngvcrd.c
+ Added some parameters to the new png_set_keep_unknown_chunks() function.
+ Added a test for up->location != 0 in the first instance of writing
+ unknown chunks in pngwrite.c
+ Changed "num" to "i" in png_free_spalettes() and png_free_unknowns() to
+ prevent recursion.
+ Added png_free_hIST() function.
+ Various patches to fix bugs in the sCAL and integer cHRM processing,
+ and to add some convenience macros for use with sCAL.
+
+Version 1.0.5j [December 21, 1999]
+ Changed "unit" parameter of png_write_sCAL from png_byte to int, to work
+ around buggy compilers.
+ Added new type "png_fixed_point" for integers that hold float*100000 values
+ Restored backward compatibility of tEXt/zTXt chunk processing:
+ Restored the first four members of png_text to the same order as v.1.0.5d.
+ Added members "lang_key" and "itxt_length" to png_text struct. Set
+ text_length=0 when "text" contains iTXt data. Use the "compression"
+ member to distinguish among tEXt/zTXt/iTXt types. Added
+ PNG_ITXT_COMPRESSION_NONE (1) and PNG_ITXT_COMPRESSION_zTXt(2) macros.
+ The "Note" above, about backward incompatibility of libpng-1.0.5e, no
+ longer applies.
+ Fixed png_read|write_iTXt() to read|write parameters in the right order,
+ and to write the iTXt chunk after IDAT if it appears in the end_ptr.
+ Added pnggccrd.c, version of pngvcrd.c Intel assembler for gcc (Greg Roelofs)
+ Reversed the order of trying to write floating-point and fixed-point gAMA.
+
+Version 1.0.5k [December 27, 1999]
+ Added many parentheses, e.g., "if (a && b & c)" becomes "if (a && (b & c))"
+ Added png_handle_as_unknown() function (Glenn)
+ Added png_free_chunk_list() function and chunk_list and num_chunk_list members
+ of png_ptr.
+ Eliminated erroneous warnings about multiple sPLT chunks and sPLT-after-PLTE.
+ Fixed a libpng-1.0.5h bug in pngrutil.c that was issuing erroneous warnings
+ about ignoring incorrect gAMA with sRGB (gAMA was in fact not ignored)
+ Added png_free_tRNS(); png_set_tRNS() now malloc's its own trans array (ESR).
+ Define png_get_int_32 when oFFs chunk is supported as well as when pCAL is.
+ Changed type of proflen from png_int_32 to png_uint_32 in png_get_iCCP().
+
+Version 1.0.5l [January 1, 2000]
+ Added functions png_set_read_user_chunk_fn() and png_get_user_chunk_ptr()
+ for setting a callback function to handle unknown chunks and for
+ retrieving the associated user pointer (Glenn).
+
+Version 1.0.5m [January 7, 2000]
+ Added high-level functions png_read_png(), png_write_png(), png_free_pixels().
+
+Version 1.0.5n [January 9, 2000]
+ Added png_free_PLTE() function, and modified png_set_PLTE() to malloc its
+ own memory for info_ptr->palette. This makes it safe for the calling
+ application to free its copy of the palette any time after it calls
+ png_set_PLTE().
+
+Version 1.0.5o [January 20, 2000]
+ Cosmetic changes only (removed some trailing blanks and TABs)
+
+Version 1.0.5p [January 31, 2000]
+ Renamed pngdll.mak to makefile.bd32
+ Cosmetic changes in pngtest.c
+
+Version 1.0.5q [February 5, 2000]
+ Relocated the makefile.solaris warning about PATH problems.
+ Fixed pngvcrd.c bug by pushing/popping registers in mmxsupport (Bruce Oberg)
+ Revised makefile.gcmmx
+ Added PNG_SETJMP_SUPPORTED, PNG_SETJMP_NOT_SUPPORTED, and PNG_ABORT() macros
+
+Version 1.0.5r [February 7, 2000]
+ Removed superfluous prototype for png_get_itxt from png.h
+ Fixed a bug in pngrtran.c that improperly expanded the background color.
+ Return *num_text=0 from png_get_text() when appropriate, and fix documentation
+ of png_get_text() in libpng.txt/libpng.3.
+
+Version 1.0.5s [February 18, 2000]
+ Added "png_jmp_env()" macro to pngconf.h, to help people migrate to the
+ new error handler that's planned for the next libpng release, and changed
+ example.c, pngtest.c, and contrib programs to use this macro.
+ Revised some of the DLL-export macros in pngconf.h (Greg Roelofs)
+ Fixed a bug in png_read_png() that caused it to fail to expand some images
+ that it should have expanded.
+ Fixed some mistakes in the unused and undocumented INCH_CONVERSIONS functions
+ in pngget.c
+ Changed the allocation of palette, history, and trans arrays back to
+ the version 1.0.5 method (linking instead of copying) which restores
+ backward compatibility with version 1.0.5. Added some remarks about
+ that in example.c. Added "free_me" member to info_ptr and png_ptr
+ and added png_free_data() function.
+ Updated makefile.linux and makefile.gccmmx to make directories conditionally.
+ Made cosmetic changes to pngasmrd.h
+ Added png_set_rows() and png_get_rows(), for use with png_read|write_png().
+ Modified png_read_png() to allocate info_ptr->row_pointers only if it
+ hasn't already been allocated.
+
+Version 1.0.5t [March 4, 2000]
+ Changed png_jmp_env() migration aiding macro to png_jmpbuf().
+ Fixed "interlace" typo (should be "interlaced") in contrib/gregbook/read2-x.c
+ Fixed bug with use of PNG_BEFORE_IHDR bit in png_ptr->mode, introduced when
+ PNG_FLAG_HAVE_CHUNK_HEADER was moved into png_ptr->mode in version 1.0.5b
+ Files in contrib/gregbook were revised to use png_jmpbuf() and to select
+ a 24-bit visual if one is available, and to allow abbreviated options.
+ Files in contrib/pngminus were revised to use the png_jmpbuf() macro.
+ Removed spaces in makefile.linux and makefile.gcmmx, introduced in 1.0.5s
+
+Version 1.0.5u [March 5, 2000]
+ Simplified the code that detects old png.h in png.c and pngtest.c
+ Renamed png_spalette (_p, _pp) to png_sPLT_t (_tp, _tpp)
+ Increased precision of rgb_to_gray calculations from 8 to 15 bits and
+ added png_set_rgb_to_gray_fixed() function.
+ Added makefile.bc32 (32-bit Borland C++, C mode)
+
+Version 1.0.5v [March 11, 2000]
+ Added some parentheses to the png_jmpbuf macro definition.
+ Updated references to the zlib home page, which has moved to freesoftware.com.
+ Corrected bugs in documentation regarding png_read_row() and png_write_row().
+ Updated documentation of png_rgb_to_gray calculations in libpng.3/libpng.txt.
+ Renamed makefile.borland,turboc3 back to makefile.bor,tc3 as in version 1.0.3,
+ revised borland makefiles; added makefile.ibmvac3 and makefile.gcc (Cosmin)
+
+Version 1.0.6 [March 20, 2000]
+ Minor revisions of makefile.bor, libpng.txt, and gregbook/rpng2-win.c
+ Added makefile.sggcc (SGI IRIX with gcc)
+
+Version 1.0.6d [April 7, 2000]
+ Changed sprintf() to strcpy() in png_write_sCAL_s() to work without STDIO
+ Added data_length parameter to png_decompress_chunk() function
+ Revised documentation to remove reference to abandoned png_free_chnk functions
+ Fixed an error in png_rgb_to_gray_fixed()
+ Revised example.c, usage of png_destroy_write_struct().
+ Renamed makefile.ibmvac3 to makefile.ibmc, added libpng.icc IBM project file
+ Added a check for info_ptr->free_me&PNG_FREE_TEXT when freeing text in png.c
+ Simplify png_sig_bytes() function to remove use of non-ISO-C strdup().
+
+Version 1.0.6e [April 9, 2000]
+ Added png_data_freer() function.
+ In the code that checks for over-length tRNS chunks, added check of
+ info_ptr->num_trans as well as png_ptr->num_trans (Matthias Benckmann)
+ Minor revisions of libpng.txt/libpng.3.
+ Check for existing data and free it if the free_me flag is set, in png_set_*()
+ and png_handle_*().
+ Only define PNG_WEIGHTED_FILTERS_SUPPORTED when PNG_FLOATING_POINT_SUPPORTED
+ is defined.
+ Changed several instances of PNG_NO_CONSOLE_ID to PNG_NO_STDIO in pngrutil.c
+ and mentioned the purposes of the two macros in libpng.txt/libpng.3.
+
+Version 1.0.6f [April 14, 2000]
+ Revised png_set_iCCP() and png_set_rows() to avoid prematurely freeing data.
+ Add checks in png_set_text() for NULL members of the input text structure.
+ Revised libpng.txt/libpng.3.
+ Removed superfluous prototype for png_set_iTXt from png.h
+ Removed "else" from pngread.c, after png_error(), and changed "0" to "length".
+ Changed several png_errors about malformed ancillary chunks to png_warnings.
+
+Version 1.0.6g [April 24, 2000]
+ Added png_pass-* arrays to pnggccrd.c when PNG_USE_LOCAL_ARRAYS is defined.
+ Relocated paragraph about png_set_background() in libpng.3/libpng.txt
+ and other revisions (Matthias Benckmann)
+ Relocated info_ptr->free_me, png_ptr->free_me, and other info_ptr and
+ png_ptr members to restore binary compatibility with libpng-1.0.5
+ (breaks compatibility with libpng-1.0.6).
+
+Version 1.0.6h [April 24, 2000]
+ Changed shared library so-number pattern from 2.x.y.z to xy.z (this builds
+ libpng.so.10 & libpng.so.10.6h instead of libpng.so.2 & libpng.so.2.1.0.6h)
+ This is a temporary change for test purposes.
+
+Version 1.0.6i [May 2, 2000]
+ Rearranged some members at the end of png_info and png_struct, to put
+ unknown_chunks_num and free_me within the original size of the png_structs
+ and free_me, png_read_user_fn, and png_free_fn within the original png_info,
+ because some old applications allocate the structs directly instead of
+ using png_create_*().
+ Added documentation of user memory functions in libpng.txt/libpng.3
+ Modified png_read_png so that it will use user_allocated row_pointers
+ if present, unless free_me directs that it be freed, and added description
+ of the use of png_set_rows() and png_get_rows() in libpng.txt/libpng.3.
+ Added PNG_LEGACY_SUPPORTED macro, and #ifdef out all new (since version
+ 1.00) members of png_struct and png_info, to regain binary compatibility
+ when you define this macro. Capabilities lost in this event
+ are user transforms (new in version 1.0.0),the user transform pointer
+ (new in version 1.0.2), rgb_to_gray (new in 1.0.5), iCCP, sCAL, sPLT,
+ the high-level interface, and unknown chunks support (all new in 1.0.6).
+ This was necessary because of old applications that allocate the structs
+ directly as authors were instructed to do in libpng-0.88 and earlier,
+ instead of using png_create_*().
+ Added modes PNG_CREATED_READ_STRUCT and PNG_CREATED_WRITE_STRUCT which
+ can be used to detect codes that directly allocate the structs, and
+ code to check these modes in png_read_init() and png_write_init() and
+ generate a libpng error if the modes aren't set and PNG_LEGACY_SUPPORTED
+ was not defined.
+ Added makefile.intel and updated makefile.watcom (Pawel Mrochen)
+
+Version 1.0.6j [May 3, 2000]
+ Overloaded png_read_init() and png_write_init() with macros that convert
+ calls to png_read_init_2() or png_write_init_2() that check the version
+ and structure sizes.
+
+Version 1.0.7beta11 [May 7, 2000]
+ Removed the new PNG_CREATED_READ_STRUCT and PNG_CREATED_WRITE_STRUCT modes
+ which are no longer used.
+ Eliminated the three new members of png_text when PNG_LEGACY_SUPPORTED is
+ defined or when neither PNG_READ_iTXt_SUPPORTED nor PNG_WRITE_iTXT_SUPPORTED
+ is defined.
+ Made PNG_NO_READ|WRITE_iTXt the default setting, to avoid memory
+ overrun when old applications fill the info_ptr->text structure directly.
+ Added PNGAPI macro, and added it to the definitions of all exported functions.
+ Relocated version macro definitions ahead of the includes of zlib.h and
+ pngconf.h in png.h.
+
+Version 1.0.7beta12 [May 12, 2000]
+ Revised pngset.c to avoid a problem with expanding the png_debug macro.
+ Deleted some extraneous defines from pngconf.h
+ Made PNG_NO_CONSOLE_IO the default condition when PNG_BUILD_DLL is defined.
+ Use MSC _RPTn debugging instead of fprintf if _MSC_VER is defined.
+ Added png_access_version_number() function.
+ Check for mask&PNG_FREE_CHNK (for TEXT, SCAL, PCAL) in png_free_data().
+ Expanded libpng.3/libpng.txt information about png_data_freer().
+
+Version 1.0.7beta14 [May 17, 2000] (beta13 was not published)
+ Changed pnggccrd.c and pngvcrd.c to handle bad adaptive filter types as
+ warnings instead of errors, as pngrutil.c does.
+ Set the PNG_INFO_IDAT valid flag in png_set_rows() so png_write_png()
+ will actually write IDATs.
+ Made the default PNG_USE_LOCAL_ARRAYS depend on PNG_DLL instead of WIN32.
+ Make png_free_data() ignore its final parameter except when freeing data
+ that can have multiple instances (text, sPLT, unknowns).
+ Fixed a new bug in png_set_rows().
+ Removed info_ptr->valid tests from png_free_data(), as in version 1.0.5.
+ Added png_set_invalid() function.
+ Fixed incorrect illustrations of png_destroy_write_struct() in example.c.
+
+Version 1.0.7beta15 [May 30, 2000]
+ Revised the deliberately erroneous Linux setjmp code in pngconf.h to produce
+ fewer error messages.
+ Rearranged checks for Z_OK to check the most likely path first in pngpread.c
+ and pngwutil.c.
+ Added checks in pngtest.c for png_create_*() returning NULL, and mentioned
+ in libpng.txt/libpng.3 the need for applications to check this.
+ Changed names of png_default_*() functions in pngtest to pngtest_*().
+ Changed return type of png_get_x|y_offset_*() from png_uint_32 to png_int_32.
+ Fixed some bugs in the unused PNG_INCH_CONVERSIONS functions in pngget.c
+ Set each pointer to NULL after freeing it in png_free_data().
+ Worked around a problem in pngconf.h; AIX's strings.h defines an "index"
+ macro that conflicts with libpng's png_color_16.index. (Dimitri
+ Papadapoulos)
+ Added "msvc" directory with MSVC++ project files (Simon-Pierre Cadieux).
+
+Version 1.0.7beta16 [June 4, 2000]
+ Revised the workaround of AIX string.h "index" bug.
+ Added a check for overlength PLTE chunk in pngrutil.c.
+ Added PNG_NO_POINTER_INDEXING macro to use array-indexing instead of pointer
+ indexing in pngrutil.c and pngwutil.c to accommodate a buggy compiler.
+ Added a warning in png_decompress_chunk() when it runs out of data, e.g.
+ when it tries to read an erroneous PhotoShop iCCP chunk.
+ Added PNG_USE_DLL macro.
+ Revised the copyright/disclaimer/license notice.
+ Added contrib/msvctest directory
+
+Version 1.0.7rc1 [June 9, 2000]
+ Corrected the definition of PNG_TRANSFORM_INVERT_ALPHA (0x0400 not 0x0200)
+ Added contrib/visupng directory (Willem van Schaik)
+
+Version 1.0.7beta18 [June 23, 2000]
+ Revised PNGAPI definition, and pngvcrd.c to work with __GCC__
+ and do not redefine PNGAPI if it is passed in via a compiler directive.
+ Revised visupng/PngFile.c to remove returns from within the Try block.
+ Removed leading underscores from "_PNG_H" and "_PNG_SAVE_BSD_SOURCE" macros.
+ Updated contrib/visupng/cexcept.h to version 1.0.0.
+ Fixed bugs in pngwrite.c and pngwutil.c that prevented writing iCCP chunks.
+
+Version 1.0.7rc2 [June 28, 2000]
+ Updated license to include disclaimers required by UCITA.
+ Fixed "DJBPP" typo in pnggccrd.c introduced in beta18.
+
+Version 1.0.7 [July 1, 2000]
+ Revised the definition of "trans_values" in libpng.3/libpng.txt
+
+Version 1.0.8beta1 [July 8, 2000]
+ Added png_free(png_ptr, key) two places in pngpread.c to stop memory leaks.
+ Changed PNG_NO_STDIO to PNG_NO_CONSOLE_IO, several places in pngrutil.c and
+ pngwutil.c.
+ Changed PNG_EXPORT_VAR to use PNG_IMPEXP, in pngconf.h.
+ Removed unused "#include <assert.h>" from png.c
+ Added WindowsCE support.
+ Revised pnggccrd.c to work with gcc-2.95.2 and in the Cygwin environment.
+
+Version 1.0.8beta2 [July 10, 2000]
+ Added project files to the wince directory and made further revisions
+ of pngtest.c, pngrio.c, and pngwio.c in support of WindowsCE.
+
+Version 1.0.8beta3 [July 11, 2000]
+ Only set the PNG_FLAG_FREE_TRNS or PNG_FREE_TRNS flag in png_handle_tRNS()
+ for indexed-color input files to avoid potential double-freeing trans array
+ under some unusual conditions; problem was introduced in version 1.0.6f.
+ Further revisions to pngtest.c and files in the wince subdirectory.
+
+Version 1.0.8beta4 [July 14, 2000]
+ Added the files pngbar.png and pngbar.jpg to the distribution.
+ Added makefile.cygwin, and cygwin support in pngconf.h
+ Added PNG_NO_ZALLOC_ZERO macro (makes png_zalloc skip zeroing memory)
+
+Version 1.0.8rc1 [July 16, 2000]
+ Revised png_debug() macros and statements to eliminate compiler warnings.
+
+Version 1.0.8 [July 24, 2000]
+ Added png_flush() in pngwrite.c, after png_write_IEND().
+ Updated makefile.hpux to build a shared library.
+
+Version 1.0.9beta1 [November 10, 2000]
+ Fixed typo in scripts/makefile.hpux
+ Updated makevms.com in scripts and contrib/* and contrib/* (Martin Zinser)
+ Fixed seqence-point bug in contrib/pngminus/png2pnm (Martin Zinser)
+ Changed "cdrom.com" in documentation to "libpng.org"
+ Revised pnggccrd.c to get it all working, and updated makefile.gcmmx (Greg).
+ Changed type of "params" from voidp to png_voidp in png_read|write_png().
+ Make sure PNGAPI and PNG_IMPEXP are defined in pngconf.h.
+ Revised the 3 instances of WRITEFILE in pngtest.c.
+ Relocated "msvc" and "wince" project subdirectories into "dll" subdirectory.
+ Updated png.rc in dll/msvc project
+ Revised makefile.dec to define and use LIBPATH and INCPATH
+ Increased size of global png_libpng_ver[] array from 12 to 18 chars.
+ Made global png_libpng_ver[], png_sig[] and png_pass_*[] arrays const.
+ Removed duplicate png_crc_finish() from png_handle_bKGD() function.
+ Added a warning when application calls png_read_update_info() multiple times.
+ Revised makefile.cygwin
+ Fixed bugs in iCCP support in pngrutil.c and pngwutil.c.
+ Replaced png_set_empty_plte_permitted() with png_permit_mng_features().
+
+Version 1.0.9beta2 [November 19, 2000]
+ Renamed the "dll" subdirectory "projects".
+ Added borland project files to "projects" subdirectory.
+ Set VS_FF_PRERELEASE and VS_FF_PATCHED flags in msvc/png.rc when appropriate.
+ Add error message in png_set_compression_buffer_size() when malloc fails.
+
+Version 1.0.9beta3 [November 23, 2000]
+ Revised PNG_LIBPNG_BUILD_TYPE macro in png.h, used in the msvc project.
+ Removed the png_flush() in pngwrite.c that crashes some applications
+ that don't set png_output_flush_fn.
+ Added makefile.macosx and makefile.aix to scripts directory.
+
+Version 1.0.9beta4 [December 1, 2000]
+ Change png_chunk_warning to png_warning in png_check_keyword().
+ Increased the first part of msg buffer from 16 to 18 in png_chunk_error().
+
+Version 1.0.9beta5 [December 15, 2000]
+ Added support for filter method 64 (for PNG datastreams embedded in MNG).
+
+Version 1.0.9beta6 [December 18, 2000]
+ Revised png_set_filter() to accept filter method 64 when appropriate.
+ Added new PNG_HAVE_PNG_SIGNATURE bit to png_ptr->mode and use it to
+ help prevent applications from using MNG features in PNG datastreams.
+ Added png_permit_mng_features() function.
+ Revised libpng.3/libpng.txt. Changed "filter type" to "filter method".
+
+Version 1.0.9rc1 [December 23, 2000]
+ Revised test for PNG_HAVE_PNG_SIGNATURE in pngrutil.c
+ Fixed error handling of unknown compression type in png_decompress_chunk().
+ In pngconf.h, define __cdecl when _MSC_VER is defined.
+
+Version 1.0.9beta7 [December 28, 2000]
+ Changed PNG_TEXT_COMPRESSION_zTXt to PNG_COMPRESSION_TYPE_BASE several places.
+ Revised memory management in png_set_hIST and png_handle_hIST in a backward
+ compatible manner. PLTE and tRNS were revised similarly.
+ Revised the iCCP chunk reader to ignore trailing garbage.
+
+Version 1.0.9beta8 [January 12, 2001]
+ Moved pngasmrd.h into pngconf.h.
+ Improved handling of out-of-spec garbage iCCP chunks generated by PhotoShop.
+
+Version 1.0.9beta9 [January 15, 2001]
+ Added png_set_invalid, png_permit_mng_features, and png_mmx_supported to
+ wince and msvc project module definition files.
+ Minor revision of makefile.cygwin.
+ Fixed bug with progressive reading of narrow interlaced images in pngpread.c
+
+Version 1.0.9beta10 [January 16, 2001]
+ Do not typedef png_FILE_p in pngconf.h when PNG_NO_STDIO is defined.
+ Fixed "png_mmx_supported" typo in project definition files.
+
+Version 1.0.9beta11 [January 19, 2001]
+ Updated makefile.sgi to make shared library.
+ Removed png_mmx_support() function and disabled PNG_MNG_FEATURES_SUPPORTED
+ by default, for the benefit of DLL forward compatibility. These will
+ be re-enabled in version 1.2.0.
+
+Version 1.0.9rc2 [January 22, 2001]
+ Revised cygwin support.
+
+Version 1.0.9 [January 31, 2001]
+ Added check of cygwin's ALL_STATIC in pngconf.h
+ Added "-nommx" parameter to contrib/gregbook/rpng2-win and rpng2-x demos.
+
+Version 1.0.10beta1 [March 14, 2001]
+ Revised makefile.dec, makefile.sgi, and makefile.sggcc; added makefile.hpgcc.
+ Reformatted libpng.3 to eliminate bad line breaks.
+ Added checks for _mmx_supported in the read_filter_row function of pnggccrd.c
+ Added prototype for png_mmx_support() near the top of pnggccrd.c
+ Moved some error checking from png_handle_IHDR to png_set_IHDR.
+ Added PNG_NO_READ_SUPPORTED and PNG_NO_WRITE_SUPPORTED macros.
+ Revised png_mmx_support() function in pnggccrd.c
+ Restored version 1.0.8 PNG_WRITE_EMPTY_PLTE_SUPPORTED behavior in pngwutil.c
+ Fixed memory leak in contrib/visupng/PngFile.c
+ Fixed bugs in png_combine_row() in pnggccrd.c and pngvcrd.c (C version)
+ Added warnings when retrieving or setting gamma=0.
+ Increased the first part of msg buffer from 16 to 18 in png_chunk_warning().
+
+Version 1.0.10rc1 [March 23, 2001]
+ Changed all instances of memcpy, strcpy, and strlen to png_memcpy, png_strcpy,
+ and png_strlen.
+ Revised png_mmx_supported() function in pnggccrd.c to return proper value.
+ Fixed bug in progressive reading (pngpread.c) with small images (height < 8).
+
+Version 1.0.10 [March 30, 2001]
+ Deleted extraneous space (introduced in 1.0.9) from line 42 of makefile.cygwin
+ Added beos project files (Chris Herborth)
+
+Version 1.0.11beta1 [April 3, 2001]
+ Added type casts on several png_malloc() calls (Dimitri Papadapoulos).
+ Removed a no-longer needed AIX work-around from pngconf.h
+ Changed several "//" single-line comments to C-style in pnggccrd.c
+
+Version 1.0.11beta2 [April 11, 2001]
+ Removed PNGAPI from several functions whose prototypes did not have PNGAPI.
+ Updated scripts/pngos2.def
+
+Version 1.0.11beta3 [April 14, 2001]
+ Added checking the results of many instances of png_malloc() for NULL
+
+Version 1.0.11beta4 [April 20, 2001]
+ Undid the changes from version 1.0.11beta3. Added a check for NULL return
+ from user's malloc_fn().
+ Removed some useless type casts of the NULL pointer.
+ Added makefile.netbsd
+
+Version 1.0.11 [April 27, 2001]
+ Revised makefile.netbsd
+
+Version 1.0.12beta1 [May 14, 2001]
+ Test for Windows platform in pngconf.h when including malloc.h (Emmanuel Blot)
+ Updated makefile.cygwin and handling of Cygwin's ALL_STATIC in pngconf.h
+ Added some never-to-be-executed code in pnggccrd.c to quiet compiler warnings.
+ Eliminated the png_error about apps using png_read|write_init(). Instead,
+ libpng will reallocate the png_struct and info_struct if they are too small.
+ This retains future binary compatibility for old applications written for
+ libpng-0.88 and earlier.
+
+Version 1.2.0beta1 [May 6, 2001]
+ Bumped DLLNUM to 2.
+ Re-enabled PNG_MNG_FEATURES_SUPPORTED and enabled PNG_ASSEMBLER_CODE_SUPPORTED
+ by default.
+ Added runtime selection of MMX features.
+ Added png_set_strip_error_numbers function and related macros.
+
+Version 1.2.0beta2 [May 7, 2001]
+ Finished merging 1.2.0beta1 with version 1.0.11
+ Added a check for attempts to read or write PLTE in grayscale PNG datastreams.
+
+Version 1.2.0beta3 [May 17, 2001]
+ Enabled user memory function by default.
+ Modified png_create_struct so it passes user mem_ptr to user memory allocator.
+ Increased png_mng_features flag from png_byte to png_uint_32.
+ Bumped shared-library (so-number) and dll-number to 3.
+
+Version 1.2.0beta4 [June 23, 2001]
+ Check for missing profile length field in iCCP chunk and free chunk_data
+ in case of truncated iCCP chunk.
+ Bumped shared-library number to 3 in makefile.sgi and makefile.sggcc
+ Bumped dll-number from 2 to 3 in makefile.cygwin
+ Revised contrib/gregbook/rpng*-x.c to avoid a memory leak and to exit cleanly
+ if user attempts to run it on an 8-bit display.
+ Updated contrib/gregbook
+ Use png_malloc instead of png_zalloc to allocate palette in pngset.c
+ Updated makefile.ibmc
+ Added some typecasts to eliminate gcc 3.0 warnings. Changed prototypes
+ of png_write_oFFS width and height from png_uint_32 to png_int_32.
+ Updated example.c
+ Revised prototypes for png_debug_malloc and png_debug_free in pngtest.c
+
+Version 1.2.0beta5 [August 8, 2001]
+ Revised contrib/gregbook
+ Revised makefile.gcmmx
+ Revised pnggccrd.c to conditionally compile some thread-unsafe code only
+ when PNG_THREAD_UNSAFE_OK is defined.
+ Added tests to prevent pngwutil.c from writing a bKGD or tRNS chunk with
+ value exceeding 2^bit_depth-1
+ Revised makefile.sgi and makefile.sggcc
+ Replaced calls to fprintf(stderr,...) with png_warning() in pnggccrd.c
+ Removed restriction that do_invert_mono only operate on 1-bit opaque files
+
+Version 1.2.0 [September 1, 2001]
+ Changed a png_warning() to png_debug() in pnggccrd.c
+ Fixed contrib/gregbook/rpng-x.c, rpng2-x.c to avoid crash with XFreeGC().
+
+Version 1.2.1beta1 [October 19, 2001]
+ Revised makefile.std in contrib/pngminus
+ Include background_1 in png_struct regardless of gamma support.
+ Revised makefile.netbsd and makefile.macosx, added makefile.darwin.
+ Revised example.c to provide more details about using row_callback().
+
+Version 1.2.1beta2 [October 25, 2001]
+ Added type cast to each NULL appearing in a function call, except for
+ WINCE functions.
+ Added makefile.so9.
+
+Version 1.2.1beta3 [October 27, 2001]
+ Removed type casts from all NULLs.
+ Simplified png_create_struct_2().
+
+Version 1.2.1beta4 [November 7, 2001]
+ Revised png_create_info_struct() and png_creat_struct_2().
+ Added error message if png_write_info() was omitted.
+ Type cast NULLs appearing in function calls when _NO_PROTO or
+ PNG_TYPECAST_NULL is defined.
+
+Version 1.2.1rc1 [November 24, 2001]
+ Type cast NULLs appearing in function calls except when PNG_NO_TYPECAST_NULL
+ is defined.
+ Changed typecast of "size" argument to png_size_t in pngmem.c calls to
+ the user malloc_fn, to agree with the prototype in png.h
+ Added a pop/push operation to pnggccrd.c, to preserve Eflag (Maxim Sobolev)
+ Updated makefile.sgi to recognize LIBPATH and INCPATH.
+ Updated various makefiles so "make clean" does not remove previous major
+ version of the shared library.
+
+Version 1.2.1rc2 [December 4, 2001]
+ Always allocate 256-entry internal palette, hist, and trans arrays, to
+ avoid out-of-bounds memory reference caused by invalid PNG datastreams.
+ Added a check for prefix_length > data_length in iCCP chunk handler.
+
+Version 1.2.1 [December 7, 2001]
+ None.
+
+Version 1.2.2beta1 [February 22, 2002]
+ Fixed a bug with reading the length of iCCP profiles (Larry Reeves).
+ Revised makefile.linux, makefile.gcmmx, and makefile.sgi to generate
+ libpng.a, libpng12.so (not libpng.so.3), and libpng12/png.h
+ Revised makefile.darwin to remove "-undefined suppress" option.
+ Added checks for gamma and chromaticity values over 21474.83, which exceed
+ the limit for PNG unsigned 32-bit integers when encoded.
+ Revised calls to png_create_read_struct() and png_create_write_struct()
+ for simpler debugging.
+ Revised png_zalloc() so zlib handles errors (uses PNG_FLAG_MALLOC_NULL_MEM_OK)
+
+Version 1.2.2beta2 [February 23, 2002]
+ Check chunk_length and idat_size for invalid (over PNG_MAX_UINT) lengths.
+ Check for invalid image dimensions in png_get_IHDR.
+ Added missing "fi;" in the install target of the SGI makefiles.
+ Added install-static to all makefiles that make shared libraries.
+ Always do gamma compensation when image is partially transparent.
+
+Version 1.2.2beta3 [March 7, 2002]
+ Compute background.gray and background_1.gray even when color_type is RGB
+ in case image gets reduced to gray later.
+ Modified shared-library makefiles to install pkgconfig/libpngNN.pc.
+ Export (with PNGAPI) png_zalloc, png_zfree, and png_handle_as_unknown
+ Removed unused png_write_destroy_info prototype from png.h
+ Eliminated incorrect use of width_mmx from pnggccrd.c in pixel_bytes == 8 case
+ Added install-shared target to all makefiles that make shared libraries.
+ Stopped a double free of palette, hist, and trans when not using free_me.
+ Added makefile.32sunu for Sun Ultra 32 and makefile.64sunu for Sun Ultra 64.
+
+Version 1.2.2beta4 [March 8, 2002]
+ Compute background.gray and background_1.gray even when color_type is RGB
+ in case image gets reduced to gray later (Jason Summers).
+ Relocated a misplaced /bin/rm in the "install-shared" makefile targets
+ Added PNG_1_0_X macro which can be used to build a 1.0.x-compatible library.
+
+Version 1.2.2beta5 [March 26, 2002]
+ Added missing PNGAPI to several function definitions.
+ Check for invalid bit_depth or color_type in png_get_IHDR(), and
+ check for missing PLTE or IHDR in png_push_read_chunk() (Matthias Clasen).
+ Revised iTXt support to accept NULL for lang and lang_key.
+ Compute gamma for color components of background even when color_type is gray.
+ Changed "()" to "{}" in scripts/libpng.pc.in.
+ Revised makefiles to put png.h and pngconf.h only in $prefix/include/libpngNN
+ Revised makefiles to make symlink to libpng.so.NN in addition to libpngNN.so
+
+Version 1.2.2beta6 [March 31, 2002]
+
+Version 1.0.13beta1 [March 31, 2002]
+ Prevent png_zalloc() from trying to memset memory that it failed to acquire.
+ Add typecasts of PNG_MAX_UINT in pngset_cHRM_fixed() (Matt Holgate).
+ Ensure that the right function (user or default) is used to free the
+ png_struct after an error in png_create_read_struct_2().
+
+Version 1.2.2rc1 [April 7, 2002]
+
+Version 1.0.13rc1 [April 7, 2002]
+ Save the ebx register in pnggccrd.c (Sami Farin)
+ Add "mem_ptr = png_ptr->mem_ptr" in png_destroy_write_struct() (Paul Gardner).
+ Updated makefiles to put headers in include/libpng and remove old include/*.h.
+
+Version 1.2.2 [April 15, 2002]
+
+Version 1.0.13 [April 15, 2002]
+ Revised description of png_set_filter() in libpng.3/libpng.txt.
+ Revised makefile.netbsd and added makefile.neNNbsd and makefile.freebsd
+
+Version 1.0.13patch01 [April 17, 2002]
+
+Version 1.2.2patch01 [April 17, 2002]
+ Changed ${PNGMAJ}.${PNGVER} bug to ${PNGVER} in makefile.sgi and
+ makefile.sggcc
+ Fixed VER -> PNGVER typo in makefile.macosx and added install-static to
+ install
+ Added install: target to makefile.32sunu and makefile.64sunu
+
+Version 1.0.13patch03 [April 18, 2002]
+
+Version 1.2.2patch03 [April 18, 2002]
+ Revised 15 makefiles to link libpng.a to libpngNN.a and the include libpng
+ subdirectory to libpngNN subdirectory without the full pathname.
+ Moved generation of libpng.pc from "install" to "all" in 15 makefiles.
+
+Version 1.2.3rc1 [April 28, 2002]
+ Added install-man target to 15 makefiles (Dimitri Papadopolous-Orfanos).
+ Added $(DESTDIR) feature to 24 makefiles (Tim Mooney)
+ Fixed bug with $prefix, should be $(prefix) in makefile.hpux.
+ Updated cygwin-specific portion of pngconf.h and revised makefile.cygwin
+ Added a link from libpngNN.pc to libpng.pc in 15 makefiles.
+ Added links from include/libpngNN/*.h to include/*.h in 24 makefiles.
+ Revised makefile.darwin to make relative links without full pathname.
+ Added setjmp() at the end of png_create_*_struct_2() in case user forgets
+ to put one in their application.
+ Restored png_zalloc() and png_zfree() prototypes to version 1.2.1 and
+ removed them from module definition files.
+
+Version 1.2.3rc2 [May 1, 2002]
+ Fixed bug in reporting number of channels in pngget.c and pngset.c,
+ that was introduced in version 1.2.2beta5.
+ Exported png_zalloc(), png_zfree(), png_default_read(), png_default_write(),
+ png_default_flush(), and png_push_fill_buffer() and included them in
+ module definition files.
+ Added "libpng.pc" dependency to the "install-shared" target in 15 makefiles.
+
+Version 1.2.3rc3 [May 1, 2002]
+ Revised prototype for png_default_flush()
+ Remove old libpng.pc and libpngNN.pc before installing new ones.
+
+Version 1.2.3rc4 [May 2, 2002]
+ Typos in *.def files (png_default_read|write -> png_default_read|write_data)
+ In makefiles, changed rm libpng.NN.pc to rm libpngNN.pc
+ Added libpng-config and libpngNN-config and modified makefiles to install
+ them.
+ Changed $(MANPATH) to $(DESTDIR)$(MANPATH) in makefiles
+ Added "Win32 DLL VB" configuration to projects/msvc/libpng.dsp
+
+Version 1.2.3rc5 [May 11, 2002]
+ Changed "error" and "message" in prototypes to "error_message" and
+ "warning_message" to avoid namespace conflict.
+ Revised 15 makefiles to build libpng-config from libpng-config-*.in
+ Once more restored png_zalloc and png_zfree to regular nonexported form.
+ Restored png_default_read|write_data, png_default_flush, png_read_fill_buffer
+ to nonexported form, but with PNGAPI, and removed them from module def
+ files.
+
+Version 1.2.3rc6 [May 14, 2002]
+ Removed "PNGAPI" from png_zalloc() and png_zfree() in png.c
+ Changed "Gz" to "Gd" in projects/msvc/libpng.dsp and zlib.dsp.
+ Removed leftover libpng-config "sed" script from four makefiles.
+ Revised libpng-config creating script in 16 makefiles.
+
+Version 1.2.3 [May 22, 2002]
+ Revised libpng-config target in makefile.cygwin.
+ Removed description of png_set_mem_fn() from documentation.
+ Revised makefile.freebsd.
+ Minor cosmetic changes to 15 makefiles, e.g., $(DI) = $(DESTDIR)/$(INCDIR).
+ Revised projects/msvc/README.txt
+ Changed -lpng to -lpngNN in LDFLAGS in several makefiles.
+
+Version 1.2.4beta1 [May 24, 2002]
+ Added libpng.pc and libpng-config to "all:" target in 16 makefiles.
+ Fixed bug in 16 makefiles: $(DESTDIR)/$(LIBPATH) to $(DESTDIR)$(LIBPATH)
+ Added missing "\" before closing double quote in makefile.gcmmx.
+ Plugged various memory leaks; added png_malloc_warn() and png_set_text_2()
+ functions.
+
+Version 1.2.4beta2 [June 25, 2002]
+ Plugged memory leak of png_ptr->current_text (Matt Holgate).
+ Check for buffer overflow before reading CRC in pngpread.c (Warwick Allison)
+ Added -soname to the loader flags in makefile.dec, makefile.sgi, and
+ makefile.sggcc.
+ Added "test-installed" target to makefile.linux, makefile.gcmmx,
+ makefile.sgi, and makefile.sggcc.
+
+Version 1.2.4beta3 [June 28, 2002]
+ Plugged memory leak of row_buf in pngtest.c when there is a png_error().
+ Detect buffer overflow in pngpread.c when IDAT is corrupted with extra data.
+ Added "test-installed" target to makefile.32sunu, makefile.64sunu,
+ makefile.beos, makefile.darwin, makefile.dec, makefile.macosx,
+ makefile.solaris, makefile.hpux, makefile.hpgcc, and makefile.so9.
+
+Version 1.2.4rc1 and 1.0.14rc1 [July 2, 2002]
+ Added "test-installed" target to makefile.cygwin and makefile.sco.
+ Revised pnggccrd.c to be able to back out version 1.0.x via PNG_1_0_X macro.
+
+Version 1.2.4 and 1.0.14 [July 8, 2002]
+ Changed png_warning() to png_error() when width is too large to process.
+
+Version 1.2.4patch01 [July 20, 2002]
+ Revised makefile.cygwin to use DLL number 12 instead of 13.
+
+Version 1.2.5beta1 [August 6, 2002]
+ Added code to contrib/gregbook/readpng2.c to ignore unused chunks.
+ Replaced toucan.png in contrib/gregbook (it has been corrupt since 1.0.11)
+ Removed some stray *.o files from contrib/gregbook.
+ Changed png_error() to png_warning() about "Too much data" in pngpread.c
+ and about "Extra compressed data" in pngrutil.c.
+ Prevent png_ptr->pass from exceeding 7 in png_push_finish_row().
+ Updated makefile.hpgcc
+ Updated png.c and pnggccrd.c handling of return from png_mmx_support()
+
+Version 1.2.5beta2 [August 15, 2002]
+ Only issue png_warning() about "Too much data" in pngpread.c when avail_in
+ is nonzero.
+ Updated makefiles to install a separate libpng.so.3 with its own rpath.
+
+Version 1.2.5rc1 and 1.0.15rc1 [August 24, 2002]
+ Revised makefiles to not remove previous minor versions of shared libraries.
+
+Version 1.2.5rc2 and 1.0.15rc2 [September 16, 2002]
+ Revised 13 makefiles to remove "-lz" and "-L$(ZLIBLIB)", etc., from shared
+ library loader directive.
+ Added missing "$OBJSDLL" line to makefile.gcmmx.
+ Added missing "; fi" to makefile.32sunu.
+
+Version 1.2.5rc3 and 1.0.15rc3 [September 18, 2002]
+ Revised libpng-config script.
+
+Version 1.2.5 and 1.0.15 [October 3, 2002]
+ Revised makefile.macosx, makefile.darwin, makefile.hpgcc, and makefile.hpux,
+ and makefile.aix.
+ Relocated two misplaced PNGAPI lines in pngtest.c
+
+Version 1.2.6beta1 [October 22, 2002]
+ Commented out warning about uninitialized mmx_support in pnggccrd.c.
+ Changed "IBMCPP__" flag to "__IBMCPP__" in pngconf.h.
+ Relocated two more misplaced PNGAPI lines in pngtest.c
+ Fixed memory overrun bug in png_do_read_filler() with 16-bit datastreams,
+ introduced in version 1.0.2.
+ Revised makefile.macosx, makefile.dec, makefile.aix, and makefile.32sunu.
+
+Version 1.2.6beta2 [November 1, 2002]
+ Added libpng-config "--ldopts" output.
+ Added "AR=ar" and "ARFLAGS=rc" and changed "ar rc" to "$(AR) $(ARFLAGS)"
+ in makefiles.
+
+Version 1.2.6beta3 [July 18, 2004]
+ Reverted makefile changes from version 1.2.6beta2 and some of the changes
+ from version 1.2.6beta1; these will be postponed until version 1.2.7.
+ Version 1.2.6 is going to be a simple bugfix release.
+ Changed the one instance of "ln -sf" to "ln -f -s" in each Sun makefile.
+ Fixed potential overrun in pngerror.c by using strncpy instead of memcpy.
+ Added "#!/bin/sh" at the top of configure, for recognition of the
+ 'x' flag under Cygwin (Cosmin).
+ Optimized vacuous tests that silence compiler warnings, in png.c (Cosmin).
+ Added support for PNG_USER_CONFIG, in pngconf.h (Cosmin).
+ Fixed the special memory handler for Borland C under DOS, in pngmem.c
+ (Cosmin).
+ Removed some spurious assignments in pngrutil.c (Cosmin).
+ Replaced 65536 with 65536L, and 0xffff with 0xffffL, to silence warnings
+ on 16-bit platforms (Cosmin).
+ Enclosed shift op expressions in parentheses, to silence warnings (Cosmin).
+ Used proper type png_fixed_point, to avoid problems on 16-bit platforms,
+ in png_handle_sRGB() (Cosmin).
+ Added compression_type to png_struct, and optimized the window size
+ inside the deflate stream (Cosmin).
+ Fixed definition of isnonalpha(), in pngerror.c and pngrutil.c (Cosmin).
+ Fixed handling of unknown chunks that come after IDAT (Cosmin).
+ Allowed png_error() and png_warning() to work even if png_ptr == NULL
+ (Cosmin).
+ Replaced row_info->rowbytes with row_bytes in png_write_find_filter()
+ (Cosmin).
+ Fixed definition of PNG_LIBPNG_VER_DLLNUM (Simon-Pierre).
+ Used PNG_LIBPNG_VER and PNG_LIBPNG_VER_STRING instead of the hardcoded
+ values in png.c (Simon-Pierre, Cosmin).
+ Initialized png_libpng_ver[] with PNG_LIBPNG_VER_STRING (Simon-Pierre).
+ Replaced PNG_LIBPNG_VER_MAJOR with PNG_LIBPNG_VER_DLLNUM in png.rc
+ (Simon-Pierre).
+ Moved the definition of PNG_HEADER_VERSION_STRING near the definitions
+ of the other PNG_LIBPNG_VER_... symbols in png.h (Cosmin).
+ Relocated #ifndef PNGAPI guards in pngconf.h (Simon-Pierre, Cosmin).
+ Updated scripts/makefile.vc(a)win32 (Cosmin).
+ Updated the MSVC project (Simon-Pierre, Cosmin).
+ Updated the Borland C++ Builder project (Cosmin).
+ Avoided access to asm_flags in pngvcrd.c, if PNG_1_0_X is defined (Cosmin).
+ Commented out warning about uninitialized mmx_support in pngvcrd.c (Cosmin).
+ Removed scripts/makefile.bd32 and scripts/pngdef.pas (Cosmin).
+ Added extra guard around inclusion of Turbo C memory headers, in pngconf.h
+ (Cosmin).
+ Renamed projects/msvc/ to projects/visualc6/, and projects/borland/ to
+ projects/cbuilder5/ (Cosmin).
+ Moved projects/visualc6/png32ms.def to scripts/pngw32.def,
+ and projects/visualc6/png.rc to scripts/pngw32.rc (Cosmin).
+ Added projects/visualc6/pngtest.dsp; removed contrib/msvctest/ (Cosmin).
+ Changed line endings to DOS style in cbuilder5 and visualc6 files, even
+ in the tar.* distributions (Cosmin).
+ Updated contrib/visupng/VisualPng.dsp (Cosmin).
+ Updated contrib/visupng/cexcept.h to version 2.0.0 (Cosmin).
+ Added a separate distribution with "configure" and supporting files (Junichi).
+
+Version 1.2.6beta4 [July 28, 2004]
+ Added user ability to change png_size_t via a PNG_SIZE_T macro.
+ Added png_sizeof() and png_convert_size() functions.
+ Added PNG_SIZE_MAX (maximum value of a png_size_t variable.
+ Added check in png_malloc_default() for (size_t)size != (png_uint_32)size
+ which would indicate an overflow.
+ Changed sPLT failure action from png_error to png_warning and abandon chunk.
+ Changed sCAL and iCCP failures from png_error to png_warning and abandon.
+ Added png_get_uint_31(png_ptr, buf) function.
+ Added PNG_UINT_32_MAX macro.
+ Renamed PNG_MAX_UINT to PNG_UINT_31_MAX.
+ Made png_zalloc() issue a png_warning and return NULL on potential
+ overflow.
+ Turn on PNG_NO_ZALLOC_ZERO by default in version 1.2.x
+ Revised "clobber list" in pnggccrd.c so it will compile under gcc-3.4.
+ Revised Borland portion of png_malloc() to return NULL or issue
+ png_error() according to setting of PNG_FLAG_MALLOC_NULL_MEM_OK.
+ Added PNG_NO_SEQUENTIAL_READ_SUPPORTED macro to conditionally remove
+ sequential read support.
+ Added some "#if PNG_WRITE_SUPPORTED" blocks.
+ Added #ifdef to remove some redundancy in png_malloc_default().
+ Use png_malloc instead of png_zalloc to allocate the pallete.
+
+Version 1.0.16rc1 and 1.2.6rc1 [August 4, 2004]
+ Fixed buffer overflow vulnerability in png_handle_tRNS()
+ Fixed integer arithmetic overflow vulnerability in png_read_png().
+ Fixed some harmless bugs in png_handle_sBIT, etc, that would cause
+ duplicate chunk types to go undetected.
+ Fixed some timestamps in the -config version
+ Rearranged order of processing of color types in png_handle_tRNS().
+ Added ROWBYTES macro to calculate rowbytes without integer overflow.
+ Updated makefile.darwin and removed makefile.macosx from scripts directory.
+ Imposed default one million column, one-million row limits on the image
+ dimensions, and added png_set_user_limits() function to override them.
+ Revised use of PNG_SET_USER_LIMITS_SUPPORTED macro.
+ Fixed wrong cast of returns from png_get_user_width|height_max().
+ Changed some "keep the compiler happy" from empty statements to returns,
+ Revised libpng.txt to remove 1.2.x stuff from the 1.0.x distribution
+
+Version 1.0.16rc2 and 1.2.6rc2 [August 7, 2004]
+ Revised makefile.darwin and makefile.solaris. Removed makefile.macosx.
+ Revised pngtest's png_debug_malloc() to use png_malloc() instead of
+ png_malloc_default() which is not supposed to be exported.
+ Fixed off-by-one error in one of the conversions to PNG_ROWBYTES() in
+ pngpread.c. Bug was introduced in 1.2.6rc1.
+ Fixed bug in RGB to RGBX transformation introduced in 1.2.6rc1.
+ Fixed old bug in RGB to Gray transformation.
+ Fixed problem with 64-bit compilers by casting arguments to abs()
+ to png_int_32.
+ Changed "ln -sf" to "ln -f -s" in three makefiles (solaris, sco, so9).
+ Changed "HANDLE_CHUNK_*" to "PNG_HANDLE_CHUNK_*" (Cosmin)
+ Added "-@/bin/rm -f $(DL)/$(LIBNAME).so.$(PNGMAJ)" to 15 *NIX makefiles.
+ Added code to update the row_info->colortype in png_do_read_filler() (MSB).
+
+Version 1.0.16rc3 and 1.2.6rc3 [August 9, 2004]
+ Eliminated use of "abs()" in testing cHRM and gAMA values, to avoid
+ trouble with some 64-bit compilers. Created PNG_OUT_OF_RANGE() macro.
+ Revised documentation of png_set_keep_unknown_chunks().
+ Check handle_as_unknown status in pngpread.c, as in pngread.c previously.
+ Moved "PNG_HANDLE_CHUNK_*" macros out of PNG_INTERNAL section of png.h
+ Added "rim" definitions for CONST4 and CONST6 in pnggccrd.c
+
+Version 1.0.16rc4 and 1.2.6rc4 [August 10, 2004]
+ Fixed mistake in pngtest.c introduced in 1.2.6rc2 (declaration of
+ "pinfo" was out of place).
+
+Version 1.0.16rc5 and 1.2.6rc5 [August 10, 2004]
+ Moved "PNG_HANDLE_CHUNK_*" macros out of PNG_ASSEMBLER_CODE_SUPPORTED
+ section of png.h where they were inadvertently placed in version rc3.
+
+Version 1.2.6 and 1.0.16 [August 15, 2004]
+ Revised pngtest so memory allocation testing is only done when PNG_DEBUG==1.
+
+Version 1.2.7beta1 [August 26, 2004]
+ Removed unused pngasmrd.h file.
+ Removed references to uu.net for archived files. Added references to
+ PNG Spec (second edition) and the PNG ISO/IEC Standard.
+ Added "test-dd" target in 15 makefiles, to run pngtest in DESTDIR.
+ Fixed bug with "optimized window size" in the IDAT datastream, that
+ causes libpng to write PNG files with incorrect zlib header bytes.
+
+Version 1.2.7beta2 [August 28, 2004]
+ Fixed bug with sCAL chunk and big-endian machines (David Munro).
+ Undid new code added in 1.2.6rc2 to update the color_type in
+ png_set_filler().
+ Added png_set_add_alpha() that updates color type.
+
+Version 1.0.17rc1 and 1.2.7rc1 [September 4, 2004]
+ Revised png_set_strip_filler() to not remove alpha if color_type has alpha.
+
+Version 1.2.7 and 1.0.17 [September 12, 2004]
+ Added makefile.hp64
+ Changed projects/msvc/png32ms.def to scripts/png32ms.def in makefile.cygwin
+
+Version 1.2.8beta1 [November 1, 2004]
+ Fixed bug in png_text_compress() that would fail to complete a large block.
+ Fixed bug, introduced in libpng-1.2.7, that overruns a buffer during
+ strip alpha operation in png_do_strip_filler().
+ Added PNG_1_2_X definition in pngconf.h
+ Use #ifdef to comment out png_info_init in png.c and png_read_init in
+ pngread.c (as of 1.3.0)
+
+Version 1.2.8beta2 [November 2, 2004]
+ Reduce color_type to a nonalpha type after strip alpha operation in
+ png_do_strip_filler().
+
+Version 1.2.8beta3 [November 3, 2004]
+ Revised definitions of PNG_MAX_UINT_32, PNG_MAX_SIZE, and PNG_MAXSUM
+
+Version 1.2.8beta4 [November 12, 2004]
+ Fixed (again) definition of PNG_LIBPNG_VER_DLLNUM in png.h (Cosmin).
+ Added PNG_LIBPNG_BUILD_PRIVATE in png.h (Cosmin).
+ Set png_ptr->zstream.data_type to Z_BINARY, to avoid unnecessary detection
+ of data type in deflate (Cosmin).
+ Deprecated but continue to support SPECIALBUILD and PRIVATEBUILD in favor of
+ PNG_LIBPNG_BUILD_SPECIAL_STRING and PNG_LIBPNG_BUILD_PRIVATE_STRING.
+
+Version 1.2.8beta5 [November 20, 2004]
+ Use png_ptr->flags instead of png_ptr->transformations to pass
+ PNG_STRIP_ALPHA info to png_do_strip_filler(), to preserve ABI
+ compatibility.
+ Revised handling of SPECIALBUILD, PRIVATEBUILD,
+ PNG_LIBPNG_BUILD_SPECIAL_STRING and PNG_LIBPNG_BUILD_PRIVATE_STRING.
+
+Version 1.2.8rc1 [November 24, 2004]
+ Moved handling of BUILD macros from pngconf.h to png.h
+ Added definition of PNG_LIBPNG_BASE_TYPE in png.h, inadvertently
+ omitted from beta5.
+ Revised scripts/pngw32.rc
+ Despammed mailing addresses by masking "@" with "at".
+ Inadvertently installed a supposedly faster test version of pngrutil.c
+
+Version 1.2.8rc2 [November 26, 2004]
+ Added two missing "\" in png.h
+ Change tests in pngread.c and pngpread.c to
+ if (png_ptr->transformations || (png_ptr->flags&PNG_FLAG_STRIP_ALPHA))
+ png_do_read_transformations(png_ptr);
+
+Version 1.2.8rc3 [November 28, 2004]
+ Reverted pngrutil.c to version libpng-1.2.8beta5.
+ Added scripts/makefile.elf with supporting code in pngconf.h for symbol
+ versioning (John Bowler).
+
+Version 1.2.8rc4 [November 29, 2004]
+ Added projects/visualc7 (Simon-pierre).
+
+Version 1.2.8rc5 [November 29, 2004]
+ Fixed new typo in scripts/pngw32.rc
+
+Version 1.2.8 [December 3, 2004]
+ Removed projects/visualc7, added projects/visualc71.
+
+Version 1.2.9beta1 [February 21, 2006]
+ Initialized some structure members in pngwutil.c to avoid gcc-4.0.0 complaints
+ Revised man page and libpng.txt to make it clear that one should not call
+ png_read_end or png_write_end after png_read_png or png_write_png.
+ Updated references to png-mng-implement mailing list.
+ Fixed an incorrect typecast in pngrutil.c
+ Added PNG_NO_READ_SUPPORTED conditional for making a write-only library.
+ Added PNG_NO_WRITE_INTERLACING_SUPPORTED conditional.
+ Optimized alpha-inversion loops in pngwtran.c
+ Moved test for nonzero gamma outside of png_build_gamma_table() in pngrtran.c
+ Make sure num_trans is <= 256 before copying data in png_set_tRNS().
+ Make sure num_palette is <= 256 before copying data in png_set_PLTE().
+ Interchanged order of write_swap_alpha and write_invert_alpha transforms.
+ Added parentheses in the definition of PNG_LIBPNG_BUILD_TYPE (Cosmin).
+ Optimized zlib window flag (CINFO) in contrib/pngsuite/*.png (Cosmin).
+ Updated scripts/makefile.bc32 for Borland C++ 5.6 (Cosmin).
+ Exported png_get_uint_32, png_save_uint_32, png_get_uint_16, png_save_uint_16,
+ png_get_int_32, png_save_int_32, png_get_uint_31 (Cosmin).
+ Added type cast (png_byte) in png_write_sCAL() (Cosmin).
+ Fixed scripts/makefile.cygwin (Christian Biesinger, Cosmin).
+ Default iTXt support was inadvertently enabled.
+
+Version 1.2.9beta2 [February 21, 2006]
+ Check for png_rgb_to_gray and png_gray_to_rgb read transformations before
+ checking for png_read_dither in pngrtran.c
+ Revised checking of chromaticity limits to accommodate extended RGB
+ colorspace (John Denker).
+ Changed line endings in some of the project files to CRLF, even in the
+ "Unix" tar distributions (Cosmin).
+ Made png_get_int_32 and png_save_int_32 always available (Cosmin).
+ Updated scripts/pngos2.def, scripts/pngw32.def and projects/wince/png32ce.def
+ with the newly exported functions.
+ Eliminated distributions without the "configure" script.
+ Updated INSTALL instructions.
+
+Version 1.2.9beta3 [February 24, 2006]
+ Fixed CRCRLF line endings in contrib/visupng/VisualPng.dsp
+ Made libpng.pc respect EXEC_PREFIX (D. P. Kreil, J. Bowler)
+ Removed reference to pngasmrd.h from Makefile.am
+ Renamed CHANGES to ChangeLog.
+ Renamed LICENSE to COPYING.
+ Renamed ANNOUNCE to NEWS.
+ Created AUTHORS file.
+
+Version 1.2.9beta4 [March 3, 2006]
+ Changed definition of PKGCONFIG from $prefix/lib to $libdir in configure.ac
+ Reverted to filenames LICENSE and ANNOUNCE; removed AUTHORS and COPYING.
+ Removed newline from the end of some error and warning messages.
+ Removed test for sqrt() from configure.ac and configure.
+ Made swap tables in pngtrans.c PNG_CONST (Carlo Bramix).
+ Disabled default iTXt support that was inadvertently enabled in
+ libpng-1.2.9beta1.
+ Added "OS2" to list of systems that don't need underscores, in pnggccrd.c
+ Removed libpng version and date from *.c files.
+
+Version 1.2.9beta5 [March 4, 2006]
+ Removed trailing blanks from source files.
+ Put version and date of latest change in each source file, and changed
+ copyright year accordingly.
+ More cleanup of configure.ac, Makefile.am, and associated scripts.
+ Restored scripts/makefile.elf which was inadvertently deleted.
+
+Version 1.2.9beta6 [March 6, 2006]
+ Fixed typo (RELEASE) in configuration files.
+
+Version 1.2.9beta7 [March 7, 2006]
+ Removed libpng.vers and libpng.sym from libpng12_la_SOURCES in Makefile.am
+ Fixed inconsistent #ifdef's around png_sig_bytes() and png_set_sCAL_s()
+ in png.h.
+ Updated makefile.elf as suggested by debian.
+ Made cosmetic changes to some makefiles, adding LN_SF and other macros.
+ Made some makefiles accept "exec_prefix".
+
+Version 1.2.9beta8 [March 9, 2006]
+ Fixed some "#if defined (..." which should be "#if defined(..."
+ Bug introduced in libpng-1.2.8.
+ Fixed inconsistency in definition of png_default_read_data()
+ Restored blank that was lost from makefile.sggcc "clean" target in beta7.
+ Revised calculation of "current" and "major" for irix in ltmain.sh
+ Changed "mkdir" to "MKDIR_P" in some makefiles.
+ Separated PNG_EXPAND and PNG_EXPAND_tRNS.
+ Added png_set_expand_gray_1_2_4_to_8() and deprecated
+ png_set_gray_1_2_4_to_8() which also expands tRNS to alpha.
+
+Version 1.2.9beta9 [March 10, 2006]
+ Include "config.h" in pngconf.h when available.
+ Added some checks for NULL png_ptr or NULL info_ptr (timeless)
+
+Version 1.2.9beta10 [March 20, 2006]
+ Removed extra CR from contrib/visualpng/VisualPng.dsw (Cosmin)
+ Made pnggccrd.c PIC-compliant (Christian Aichinger).
+ Added makefile.mingw (Wolfgang Glas).
+ Revised pngconf.h MMX checking.
+
+Version 1.2.9beta11 [March 22, 2006]
+ Fixed out-of-order declaration in pngwrite.c that was introduced in beta9
+ Simplified some makefiles by using LIBSO, LIBSOMAJ, and LIBSOVER macros.
+
+Version 1.2.9rc1 [March 31, 2006]
+ Defined PNG_USER_PRIVATEBUILD when including "pngusr.h" (Cosmin).
+ Removed nonsensical assertion check from pngtest.c (Cosmin).
+
+Version 1.2.9 [April 14, 2006]
+ Revised makefile.beos and added "none" selector in ltmain.sh
+
+Version 1.2.10beta1 [April 15, 2006]
+ Renamed "config.h" to "png_conf.h" and revised Makefile.am to add
+ -DPNG_BUILDING_LIBPNG to compile directive, and modified pngconf.h
+ to include png_conf.h only when PNG_BUILDING_LIBPNG is defined.
+
+Version 1.2.10beta2 [April 15, 2006]
+ Manually updated Makefile.in and configure. Changed png_conf.h.in
+ back to config.h.
+
+Version 1.2.10beta3 [April 15, 2006]
+ Change png_conf.h back to config.h in pngconf.h.
+
+Version 1.2.10beta4 [April 16, 2006]
+ Change PNG_BUILDING_LIBPNG to PNG_CONFIGURE_LIBPNG in config/Makefile*.
+
+Version 1.2.10beta5 [April 16, 2006]
+ Added a configure check for compiling assembler code in pnggccrd.c
+
+Version 1.2.10beta6 [April 17, 2006]
+ Revised the configure check for pnggccrd.c
+ Moved -DPNG_CONFIGURE_LIBPNG into @LIBPNG_DEFINES@
+ Added @LIBPNG_DEFINES@ to arguments when building libpng.sym
+
+Version 1.2.10beta7 [April 18, 2006]
+ Change "exec_prefix=$prefix" to "exec_prefix=$(prefix)" in makefiles.
+
+Version 1.2.10rc1 [April 19, 2006]
+ Ensure pngconf.h doesn't define both PNG_USE_PNGGCCRD and PNG_USE_PNGVCRD
+ Fixed "LN_FS" typo in makefile.sco and makefile.solaris.
+
+Version 1.2.10rc2 [April 20, 2006]
+ Added a backslash between -DPNG_CONFIGURE_LIBPNG and -DPNG_NO_ASSEMBLER_CODE
+ in configure.ac and configure
+ Made the configure warning about versioned symbols less arrogant.
+
+Version 1.2.10rc3 [April 21, 2006]
+ Added a note in libpng.txt that png_set_sig_bytes(8) can be used when
+ writing an embedded PNG without the 8-byte signature.
+ Revised makefiles and configure to avoid making links to libpng.so.*
+
+Version 1.2.10 [April 23, 2006]
+ Reverted configure to "rc2" state.
+
+Version 1.2.11beta1 [May 31, 2006]
+ scripts/libpng.pc.in contained "configure" style version info and would
+ not work with makefiles.
+ The shared-library makefiles were linking to libpng.so.0 instead of
+ libpng.so.3 compatibility as the library.
+
+Version 1.2.11beta2 [June 2, 2006]
+ Increased sprintf buffer from 50 to 52 chars in pngrutil.c to avoid
+ buffer overflow.
+ Fixed bug in example.c (png_set_palette_rgb -> png_set_palette_to_rgb)
+
+Version 1.2.11beta3 [June 5, 2006]
+ Prepended "#! /bin/sh" to ltmail.sh and contrib/pngminus/*.sh (Cosmin).
+ Removed the accidental leftover Makefile.in~ (Cosmin).
+ Avoided potential buffer overflow and optimized buffer in
+ png_write_sCAL(), png_write_sCAL_s() (Cosmin).
+ Removed the include directories and libraries from CFLAGS and LDFLAGS
+ in scripts/makefile.gcc (Nelson A. de Oliveira, Cosmin).
+
+Version 1.2.11beta4 [June 6, 2006]
+ Allow zero-length IDAT chunks after the entire zlib datastream, but not
+ after another intervening chunk type.
+
+Version 1.0.19rc1, 1.2.11rc1 [June 13, 2006]
+ Deleted extraneous square brackets from [config.h] in configure.ac
+
+Version 1.0.19rc2, 1.2.11rc2 [June 14, 2006]
+ Added prototypes for PNG_INCH_CONVERSIONS functions to png.h
+ Revised INSTALL and autogen.sh
+ Fixed typo in several makefiles (-W1 should be -Wl)
+ Added typedef for png_int_32 and png_uint_32 on 64-bit systems.
+
+Version 1.0.19rc3, 1.2.11rc3 [June 15, 2006]
+ Removed the new typedefs for 64-bit systems (delay until version 1.4.0)
+ Added one zero element to png_gamma_shift[] array in pngrtran.c to avoid
+ reading out of bounds.
+
+Version 1.0.19rc4, 1.2.11rc4 [June 15, 2006]
+ Really removed the new typedefs for 64-bit systems.
+
+Version 1.0.19rc5, 1.2.11rc5 [June 22, 2006]
+ Removed png_sig_bytes entry from scripts/pngw32.def
+
+Version 1.0.19, 1.2.11 [June 26, 2006]
+ None.
+
+Version 1.0.20, 1.2.12 [June 27, 2006]
+ Really increased sprintf buffer from 50 to 52 chars in pngrutil.c to avoid
+ buffer overflow.
+
+Version 1.2.13beta1 [October 2, 2006]
+ Removed AC_FUNC_MALLOC from configure.ac
+ Work around Intel-Mac compiler bug by setting PNG_NO_MMX_CODE in pngconf.h
+ Change "logical" to "bitwise" throughout documentation.
+ Detect and fix attempt to write wrong iCCP profile length (CVE-2006-7244)
+
+Version 1.0.21, 1.2.13 [November 14, 2006]
+ Fix potential buffer overflow in sPLT chunk handler.
+ Fix Makefile.am to not try to link to noexistent files.
+ Check all exported functions for NULL png_ptr.
+
+Version 1.2.14beta1 [November 17, 2006]
+ Relocated three misplaced tests for NULL png_ptr.
+ Built Makefile.in with automake-1.9.6 instead of 1.9.2.
+ Build configure with autoconf-2.60 instead of 2.59
+
+Version 1.2.14beta2 [November 17, 2006]
+ Added some typecasts in png_zalloc().
+
+Version 1.2.14rc1 [November 20, 2006]
+ Changed "strtod" to "png_strtod" in pngrutil.c
+
+Version 1.0.22, 1.2.14 [November 27, 2006]
+ Added missing "$(srcdir)" in Makefile.am and Makefile.in
+
+Version 1.2.15beta1 [December 3, 2006]
+ Generated configure with autoconf-2.61 instead of 2.60
+ Revised configure.ac to update libpng.pc and libpng-config.
+
+Version 1.2.15beta2 [December 3, 2006]
+ Always export MMX asm functions, just stubs if not building pnggccrd.c
+
+Version 1.2.15beta3 [December 4, 2006]
+ Add "png_bytep" typecast to profile while calculating length in pngwutil.c
+
+Version 1.2.15beta4 [December 7, 2006]
+ Added scripts/CMakeLists.txt
+ Changed PNG_NO_ASSEMBLER_CODE to PNG_NO_MMX_CODE in scripts, like 1.4.0beta
+
+Version 1.2.15beta5 [December 7, 2006]
+ Changed some instances of PNG_ASSEMBLER_* to PNG_MMX_* in pnggccrd.c
+ Revised scripts/CMakeLists.txt
+
+Version 1.2.15beta6 [December 13, 2006]
+ Revised scripts/CMakeLists.txt and configure.ac
+
+Version 1.2.15rc1 [December 18, 2006]
+ Revised scripts/CMakeLists.txt
+
+Version 1.2.15rc2 [December 21, 2006]
+ Added conditional #undef jmpbuf in pngtest.c to undo #define in AIX headers.
+ Added scripts/makefile.nommx
+
+Version 1.2.15rc3 [December 25, 2006]
+ Fixed shared library numbering error that was introduced in 1.2.15beta6.
+
+Version 1.2.15rc4 [December 27, 2006]
+ Fixed handling of rgb_to_gray when png_ptr->color.gray isn't set.
+
+Version 1.2.15rc5 [December 31, 2006]
+ Revised handling of rgb_to_gray.
+
+Version 1.2.15 [January 5, 2007]
+ Added some (unsigned long) typecasts in pngtest.c to avoid printing errors.
+
+Version 1.2.16beta1 [January 6, 2007]
+ Fix bugs in makefile.nommx
+
+Version 1.2.16beta2 [January 16, 2007]
+ Revised scripts/CMakeLists.txt
+
+Version 1.2.16 [January 31, 2007]
+ No changes.
+
+Version 1.2.17beta1 [March 6, 2007]
+ Revised scripts/CMakeLists.txt to install both shared and static libraries.
+ Deleted a redundant line from pngset.c.
+
+Version 1.2.17beta2 [April 26, 2007]
+ Relocated misplaced test for png_ptr == NULL in pngpread.c
+ Change "==" to "&" for testing PNG_RGB_TO_GRAY_ERR & PNG_RGB_TO_GRAY_WARN
+ flags.
+ Changed remaining instances of PNG_ASSEMBLER_* to PNG_MMX_*
+ Added pngerror() when write_IHDR fails in deflateInit2().
+ Added "const" to some array declarations.
+ Mention examples of libpng usage in the libpng*.txt and libpng.3 documents.
+
+Version 1.2.17rc1 [May 4, 2007]
+ No changes.
+
+Version 1.2.17rc2 [May 8, 2007]
+ Moved several PNG_HAVE_* macros out of PNG_INTERNAL because applications
+ calling set_unknown_chunk_location() need them.
+ Changed transformation flag from PNG_EXPAND_tRNS to PNG_EXPAND in
+ png_set_expand_gray_1_2_4_to_8().
+ Added png_ptr->unknown_chunk to hold working unknown chunk data, so it
+ can be free'ed in case of error. Revised unknown chunk handling in
+ pngrutil.c and pngpread.c to use this structure.
+
+Version 1.2.17rc3 [May 8, 2007]
+ Revised symbol-handling in configure script.
+
+Version 1.2.17rc4 [May 10, 2007]
+ Revised unknown chunk handling to avoid storing unknown critical chunks.
+
+Version 1.0.25 [May 15, 2007]
+Version 1.2.17 [May 15, 2007]
+ Added "png_ptr->num_trans=0" before error return in png_handle_tRNS,
+ to eliminate a vulnerability (CVE-2007-2445, CERT VU#684664)
+
+Version 1.0.26 [May 15, 2007]
+Version 1.2.18 [May 15, 2007]
+ Reverted the libpng-1.2.17rc3 change to symbol-handling in configure script
+
+Version 1.2.19beta1 [May 18, 2007]
+ Changed "const static" to "static PNG_CONST" everywhere, mostly undoing
+ change of libpng-1.2.17beta2. Changed other "const" to "PNG_CONST"
+ Changed some handling of unused parameters, to avoid compiler warnings.
+ "if (unused == NULL) return;" becomes "unused = unused".
+
+Version 1.2.19beta2 [May 18, 2007]
+ Only use the valid bits of tRNS value in png_do_expand() (Brian Cartier)
+
+Version 1.2.19beta3 [May 19, 2007]
+ Add some "png_byte" typecasts in png_check_keyword() and write new_key
+ instead of key in zTXt chunk (Kevin Ryde).
+
+Version 1.2.19beta4 [May 21, 2007]
+ Add png_snprintf() function and use it in place of sprint() for improved
+ defense against buffer overflows.
+
+Version 1.2.19beta5 [May 21, 2007]
+ Fixed png_handle_tRNS() to only use the valid bits of tRNS value.
+ Changed handling of more unused parameters, to avoid compiler warnings.
+ Removed some PNG_CONST in pngwutil.c to avoid compiler warnings.
+
+Version 1.2.19beta6 [May 22, 2007]
+ Added some #ifdef PNG_MMX_CODE_SUPPORTED where needed in pngvcrd.c
+ Added a special "_MSC_VER" case that defines png_snprintf to _snprintf
+
+Version 1.2.19beta7 [May 22, 2007]
+ Squelched png_squelch_warnings() in pnggccrd.c and added
+ an #ifdef PNG_MMX_CODE_SUPPORTED block around the declarations that caused
+ the warnings that png_squelch_warnings was squelching.
+
+Version 1.2.19beta8 [May 22, 2007]
+ Removed __MMX__ from test in pngconf.h.
+
+Version 1.2.19beta9 [May 23, 2007]
+ Made png_squelch_warnings() available via PNG_SQUELCH_WARNINGS macro.
+ Revised png_squelch_warnings() so it might work.
+ Updated makefile.sgcc and makefile.solaris; added makefile.solaris-x86.
+
+Version 1.2.19beta10 [May 24, 2007]
+ Resquelched png_squelch_warnings(), use "__attribute__((used))" instead.
+
+Version 1.4.0beta1 [April 20, 2006]
+ Enabled iTXt support (changes png_struct, thus requires so-number change).
+ Cleaned up PNG_ASSEMBLER_CODE_SUPPORTED vs PNG_MMX_CODE_SUPPORTED
+ Eliminated PNG_1_0_X and PNG_1_2_X macros.
+ Removed deprecated functions png_read_init, png_write_init, png_info_init,
+ png_permit_empty_plte, png_set_gray_1_2_4_to_8, png_check_sig, and
+ removed the deprecated macro PNG_MAX_UINT.
+ Moved "PNG_INTERNAL" parts of png.h and pngconf.h into pngintrn.h
+ Removed many WIN32_WCE #ifdefs (Cosmin).
+ Reduced dependency on C-runtime library when on Windows (Simon-Pierre)
+ Replaced sprintf() with png_sprintf() (Simon-Pierre)
+
+Version 1.4.0beta2 [April 20, 2006]
+ Revised makefiles and configure to avoid making links to libpng.so.*
+ Moved some leftover MMX-related defines from pngconf.h to pngintrn.h
+ Updated scripts/pngos2.def, pngw32.def, and projects/wince/png32ce.def
+
+Version 1.4.0beta3 [May 10, 2006]
+ Updated scripts/pngw32.def to comment out MMX functions.
+ Added PNG_NO_GET_INT_32 and PNG_NO_SAVE_INT_32 macros.
+ Scripts/libpng.pc.in contained "configure" style version info and would
+ not work with makefiles.
+ Revised pngconf.h and added pngconf.h.in, so makefiles and configure can
+ pass defines to libpng and applications.
+
+Version 1.4.0beta4 [May 11, 2006]
+ Revised configure.ac, Makefile.am, and many of the makefiles to write
+ their defines in pngconf.h.
+
+Version 1.4.0beta5 [May 15, 2006]
+ Added a missing semicolon in Makefile.am and Makefile.in
+ Deleted extraneous square brackets from configure.ac
+
+Version 1.4.0beta6 [June 2, 2006]
+ Increased sprintf buffer from 50 to 52 chars in pngrutil.c to avoid
+ buffer overflow.
+ Changed sonum from 0 to 1.
+ Removed unused prototype for png_check_sig() from png.h
+
+Version 1.4.0beta7 [June 16, 2006]
+ Exported png_write_sig (Cosmin).
+ Optimized buffer in png_handle_cHRM() (Cosmin).
+ Set pHYs = 2835 x 2835 pixels per meter, and added
+ sCAL = 0.352778e-3 x 0.352778e-3 meters, in pngtest.png (Cosmin).
+ Added png_set_benign_errors(), png_benign_error(), png_chunk_benign_error().
+ Added typedef for png_int_32 and png_uint_32 on 64-bit systems.
+ Added "(unsigned long)" typecast on png_uint_32 variables in printf lists.
+
+Version 1.4.0beta8 [June 22, 2006]
+ Added demonstration of user chunk support in pngtest.c, to support the
+ public sTER chunk and a private vpAg chunk.
+
+Version 1.4.0beta9 [July 3, 2006]
+ Removed ordinals from scripts/pngw32.def and removed png_info_int and
+ png_set_gray_1_2_4_to_8 entries.
+ Inline call of png_get_uint_32() in png_get_uint_31().
+ Use png_get_uint_31() to get vpAg width and height in pngtest.c
+ Removed WINCE and Netware projects.
+ Removed standalone Y2KINFO file.
+
+Version 1.4.0beta10 [July 12, 2006]
+ Eliminated automatic copy of pngconf.h to pngconf.h.in from configure and
+ some makefiles, because it was not working reliably. Instead, distribute
+ pngconf.h.in along with pngconf.h and cause configure and some of the
+ makefiles to update pngconf.h from pngconf.h.in.
+ Added pngconf.h to DEPENDENCIES in Makefile.am
+
+Version 1.4.0beta11 [August 19, 2006]
+ Removed AC_FUNC_MALLOC from configure.ac.
+ Added a warning when writing iCCP profile with mismatched profile length.
+ Patched pnggccrd.c to assemble on x86_64 platforms.
+ Moved chunk header reading into a separate function png_read_chunk_header()
+ in pngrutil.c. The chunk header (len+sig) is now serialized in a single
+ operation (Cosmin).
+ Implemented support for I/O states. Added png_ptr member io_state, and
+ functions png_get_io_chunk_name() and png_get_io_state() in pngget.c
+ (Cosmin).
+ Added png_get_io_chunk_name and png_get_io_state to scripts/*.def (Cosmin).
+ Renamed scripts/pngw32.* to scripts/pngwin.* (Cosmin).
+ Removed the include directories and libraries from CFLAGS and LDFLAGS
+ in scripts/makefile.gcc (Cosmin).
+ Used png_save_uint_32() to set vpAg width and height in pngtest.c (Cosmin).
+ Cast to proper type when getting/setting vpAg units in pngtest.c (Cosmin).
+ Added pngintrn.h to the Visual C++ projects (Cosmin).
+ Removed scripts/list (Cosmin).
+ Updated copyright year in scripts/pngwin.def (Cosmin).
+ Removed PNG_TYPECAST_NULL and used standard NULL consistently (Cosmin).
+ Disallowed the user to redefine png_size_t, and enforced a consistent use
+ of png_size_t across libpng (Cosmin).
+ Changed the type of png_ptr->rowbytes, PNG_ROWBYTES() and friends
+ to png_size_t (Cosmin).
+ Removed png_convert_size() and replaced png_sizeof with sizeof (Cosmin).
+ Removed some unnecessary type casts (Cosmin).
+ Changed prototype of png_get_compression_buffer_size() and
+ png_set_compression_buffer_size() to work with png_size_t instead of
+ png_uint_32 (Cosmin).
+ Removed png_memcpy_check() and png_memset_check() (Cosmin).
+ Fixed a typo (png_byte --> png_bytep) in libpng.3 and libpng.txt (Cosmin).
+ Clarified that png_zalloc() does not clear the allocated memory,
+ and png_zalloc() and png_zfree() cannot be PNGAPI (Cosmin).
+ Renamed png_mem_size_t to png_alloc_size_t, fixed its definition in
+ pngconf.h, and used it in all memory allocation functions (Cosmin).
+ Renamed pngintrn.h to pngpriv.h, added a comment at the top of the file
+ mentioning that the symbols declared in that file are private, and
+ updated the scripts and the Visual C++ projects accordingly (Cosmin).
+ Removed circular references between pngconf.h and pngconf.h.in in
+ scripts/makefile.vc*win32 (Cosmin).
+ Removing trailing '.' from the warning and error messages (Cosmin).
+ Added pngdefs.h that is built by makefile or configure, instead of
+ pngconf.h.in (Glenn).
+ Detect and fix attempt to write wrong iCCP profile length.
+
+Version 1.4.0beta12 [October 19, 2006]
+ Changed "logical" to "bitwise" in the documentation.
+ Work around Intel-Mac compiler bug by setting PNG_NO_MMX_CODE in pngconf.h
+ Add a typecast to stifle compiler warning in pngrutil.c
+
+Version 1.4.0beta13 [November 10, 2006]
+ Fix potential buffer overflow in sPLT chunk handler.
+ Fix Makefile.am to not try to link to noexistent files.
+
+Version 1.4.0beta14 [November 15, 2006]
+ Check all exported functions for NULL png_ptr.
+
+Version 1.4.0beta15 [November 17, 2006]
+ Relocated two misplaced tests for NULL png_ptr.
+ Built Makefile.in with automake-1.9.6 instead of 1.9.2.
+ Build configure with autoconf-2.60 instead of 2.59
+ Add "install: all" in Makefile.am so "configure; make install" will work.
+
+Version 1.4.0beta16 [November 17, 2006]
+ Added a typecast in png_zalloc().
+
+Version 1.4.0beta17 [December 4, 2006]
+ Changed "new_key[79] = '\0';" to "(*new_key)[79] = '\0';" in pngwutil.c
+ Add "png_bytep" typecast to profile while calculating length in pngwutil.c
+
+Version 1.4.0beta18 [December 7, 2006]
+ Added scripts/CMakeLists.txt
+
+Version 1.4.0beta19 [May 16, 2007]
+ Revised scripts/CMakeLists.txt
+ Rebuilt configure and Makefile.in with newer tools.
+ Added conditional #undef jmpbuf in pngtest.c to undo #define in AIX headers.
+ Added scripts/makefile.nommx
+
+Version 1.4.0beta20 [July 9, 2008]
+ Moved several PNG_HAVE_* macros from pngpriv.h to png.h because applications
+ calling set_unknown_chunk_location() need them.
+ Moved several macro definitions from pngpriv.h to pngconf.h
+ Merge with changes to the 1.2.X branch, as of 1.2.30beta04.
+ Deleted all use of the MMX assembler code and Intel-licensed optimizations.
+ Revised makefile.mingw
+
+Version 1.4.0beta21 [July 21, 2008]
+ Moved local array "chunkdata" from pngrutil.c to the png_struct, so
+ it will be freed by png_read_destroy() in case of a read error (Kurt
+ Christensen).
+
+Version 1.4.0beta22 [July 21, 2008]
+ Change "purpose" and "buffer" to png_ptr->chunkdata to avoid memory leaking.
+
+Version 1.4.0beta23 [July 22, 2008]
+ Change "chunkdata = NULL" to "png_ptr->chunkdata = NULL" several places in
+ png_decompress_chunk().
+
+Version 1.4.0beta24 [July 25, 2008]
+ Change all remaining "chunkdata" to "png_ptr->chunkdata" in
+ png_decompress_chunk(), and remove "chunkdata" from parameter list.
+ Put a call to png_check_chunk_name() in png_read_chunk_header().
+ Revised png_check_chunk_name() to reject a name with a lowercase 3rd byte.
+ Removed two calls to png_check_chunk_name() occuring later in the process.
+ Define PNG_NO_ERROR_NUMBERS by default in pngconf.h
+
+Version 1.4.0beta25 [July 30, 2008]
+ Added a call to png_check_chunk_name() in pngpread.c
+ Reverted png_check_chunk_name() to accept a name with a lowercase 3rd byte.
+ Added png_push_have_buffer() function to pngpread.c
+ Eliminated PNG_BIG_ENDIAN_SUPPORTED and associated png_get_* macros.
+ Made inline expansion of png_get_*() optional with PNG_USE_READ_MACROS.
+ Eliminated all PNG_USELESS_TESTS and PNG_CORRECT_PALETTE_SUPPORTED code.
+ Synced contrib directory and configure files with libpng-1.2.30beta06.
+ Eliminated no-longer-used pngdefs.h (but it's still built in the makefiles)
+ Relocated a misplaced "#endif /* PNG_NO_WRITE_FILTER */" in pngwutil.c
+
+Version 1.4.0beta26 [August 4, 2008]
+ Removed png_push_have_buffer() function in pngpread.c. It increased the
+ compiled library size slightly.
+ Changed "-Wall" to "-W -Wall" in the CFLAGS in all makefiles (Cosmin Truta)
+ Declared png_ptr "volatile" in pngread.c and pngwrite.c to avoid warnings.
+ Updated contrib/visupng/cexcept.h to version 2.0.1
+ Added PNG_LITERAL_CHARACTER macros for #, [, and ].
+
+Version 1.4.0beta27 [August 5, 2008]
+ Revised usage of PNG_LITERAL_SHARP in pngerror.c.
+ Moved newline character from individual png_debug messages into the
+ png_debug macros.
+ Allow user to #define their own png_debug, png_debug1, and png_debug2.
+
+Version 1.4.0beta28 [August 5, 2008]
+ Revised usage of PNG_LITERAL_SHARP in pngerror.c.
+ Added PNG_STRING_NEWLINE macro
+
+Version 1.4.0beta29 [August 9, 2008]
+ Revised usage of PNG_STRING_NEWLINE to work on non-ISO compilers.
+ Added PNG_STRING_COPYRIGHT macro.
+ Added non-ISO versions of png_debug macros.
+
+Version 1.4.0beta30 [August 14, 2008]
+ Added premultiplied alpha feature (Volker Wiendl).
+
+Version 1.4.0beta31 [August 18, 2008]
+ Moved png_set_premultiply_alpha from pngtrans.c to pngrtran.c
+ Removed extra crc check at the end of png_handle_cHRM(). Bug introduced
+ in libpng-1.4.0beta20.
+
+Version 1.4.0beta32 [August 19, 2008]
+ Added PNG_WRITE_FLUSH_SUPPORTED block around new png_flush() call.
+ Revised PNG_NO_STDIO version of png_write_flush()
+
+Version 1.4.0beta33 [August 20, 2008]
+ Added png_get|set_chunk_cache_max() to limit the total number of sPLT,
+ text, and unknown chunks that can be stored.
+
+Version 1.4.0beta34 [September 6, 2008]
+ Shortened tIME_string to 29 bytes in pngtest.c
+ Fixed off-by-one error introduced in png_push_read_zTXt() function in
+ libpng-1.2.30beta04/pngpread.c (Harald van Dijk)
+
+Version 1.4.0beta35 [October 6, 2008]
+ Changed "trans_values" to "trans_color".
+ Changed so-number from 0 to 14. Some OS do not like 0.
+ Revised makefile.darwin to fix shared library numbering.
+ Change png_set_gray_1_2_4_to_8() to png_set_expand_gray_1_2_4_to_8()
+ in example.c (debian bug report)
+
+Version 1.4.0beta36 [October 25, 2008]
+ Sync with tEXt vulnerability fix in libpng-1.2.33rc02.
+
+Version 1.4.0beta37 [November 13, 2008]
+ Added png_check_cHRM in png.c and moved checking from pngget.c, pngrutil.c,
+ and pngwrite.c
+
+Version 1.4.0beta38 [November 22, 2008]
+ Added check for zero-area RGB cHRM triangle in png_check_cHRM() and
+ png_check_cHRM_fixed().
+
+Version 1.4.0beta39 [November 23, 2008]
+ Revised png_warning() to write its message on standard output by default
+ when warning_fn is NULL.
+
+Version 1.4.0beta40 [November 24, 2008]
+ Eliminated png_check_cHRM(). Instead, always use png_check_cHRM_fixed().
+ In png_check_cHRM_fixed(), ensure white_y is > 0, and removed redundant
+ check for all-zero coordinates that is detected by the triangle check.
+
+Version 1.4.0beta41 [November 26, 2008]
+ Fixed string vs pointer-to-string error in png_check_keyword().
+ Rearranged test expressions in png_check_cHRM_fixed() to avoid internal
+ overflows.
+ Added PNG_NO_CHECK_cHRM conditional.
+
+Version 1.4.0beta42, 43 [December 1, 2008]
+ Merge png_debug with version 1.2.34beta04.
+
+Version 1.4.0beta44 [December 6, 2008]
+ Removed redundant check for key==NULL before calling png_check_keyword()
+ to ensure that new_key gets initialized and removed extra warning
+ (Merge with version 1.2.34beta05 -- Arvan Pritchard).
+
+Version 1.4.0beta45 [December 9, 2008]
+ In png_write_png(), respect the placement of the filler bytes in an earlier
+ call to png_set_filler() (Jim Barry).
+
+Version 1.4.0beta46 [December 10, 2008]
+ Undid previous change and added PNG_TRANSFORM_STRIP_FILLER_BEFORE and
+ PNG_TRANSFORM_STRIP_FILLER_AFTER conditionals and deprecated
+ PNG_TRANSFORM_STRIP_FILLER (Jim Barry).
+
+Version 1.4.0beta47 [December 15, 2008]
+ Support for dithering was disabled by default, because it has never
+ been well tested and doesn't work very well. The code has not
+ been removed, however, and can be enabled by building libpng with
+ PNG_READ_DITHER_SUPPORTED defined.
+
+Version 1.4.0beta48 [February 14, 2009]
+ Added new exported function png_calloc().
+ Combined several instances of png_malloc(); png_memset() into png_calloc().
+ Removed prototype for png_freeptr() that was added in libpng-1.4.0beta24
+ but was never defined.
+
+Version 1.4.0beta49 [February 28, 2009]
+ Added png_fileno() macro to pngconf.h, used in pngwio.c
+ Corrected order of #ifdef's in png_debug definition in png.h
+ Fixed bug introduced in libpng-1.4.0beta48 with the memset arguments
+ for pcal_params.
+ Fixed order of #ifdef directives in the png_debug defines in png.h
+ (bug introduced in libpng-1.2.34/1.4.0beta29).
+ Revised comments in png_set_read_fn() and png_set_write_fn().
+
+Version 1.4.0beta50 [March 18, 2009]
+ Use png_calloc() instead of png_malloc() to allocate big_row_buf when
+ reading an interlaced file, to avoid a possible UMR.
+ Undid revision of PNG_NO_STDIO version of png_write_flush(). Users
+ having trouble with fflush() can build with PNG_NO_WRITE_FLUSH defined
+ or supply their own flush_fn() replacement.
+ Revised libpng*.txt and png.h documentation about use of png_write_flush()
+ and png_set_write_fn().
+ Removed fflush() from pngtest.c.
+ Added "#define PNG_NO_WRITE_FLUSH" to contrib/pngminim/encoder/pngusr.h
+
+Version 1.4.0beta51 [March 21, 2009]
+ Removed new png_fileno() macro from pngconf.h .
+
+Version 1.4.0beta52 [March 27, 2009]
+ Relocated png_do_chop() ahead of building gamma tables in pngrtran.c
+ This avoids building 16-bit gamma tables unnecessarily.
+ Removed fflush() from pngtest.c.
+ Added "#define PNG_NO_WRITE_FLUSH" to contrib/pngminim/encoder/pngusr.h
+ Added a section on differences between 1.0.x and 1.2.x to libpng.3/libpng.txt
+
+Version 1.4.0beta53 [April 1, 2009]
+ Removed some remaining MMX macros from pngpriv.h
+ Fixed potential memory leak of "new_name" in png_write_iCCP() (Ralph Giles)
+
+Version 1.4.0beta54 [April 13, 2009]
+ Added "ifndef PNG_SKIP_SETJMP_CHECK" block in pngconf.h to allow
+ application code writers to bypass the check for multiple inclusion
+ of setjmp.h when they know that it is safe to ignore the situation.
+ Eliminated internal use of setjmp() in pngread.c and pngwrite.c
+ Reordered ancillary chunks in pngtest.png to be the same as what
+ pngtest now produces, and made some cosmetic changes to pngtest output.
+ Eliminated deprecated png_read_init_3() and png_write_init_3() functions.
+
+Version 1.4.0beta55 [April 15, 2009]
+ Simplified error handling in pngread.c and pngwrite.c by putting
+ the new png_read_cleanup() and png_write_cleanup() functions inline.
+
+Version 1.4.0beta56 [April 25, 2009]
+ Renamed "user_chunk_data" to "my_user_chunk_data" in pngtest.c to suppress
+ "shadowed declaration" warning from gcc-4.3.3.
+ Renamed "gamma" to "png_gamma" in pngset.c to avoid "shadowed declaration"
+ warning about a global "gamma" variable in math.h on some platforms.
+
+Version 1.4.0beta57 [May 2, 2009]
+ Removed prototype for png_freeptr() that was added in libpng-1.4.0beta24
+ but was never defined (again).
+ Rebuilt configure scripts with autoconf-2.63 instead of 2.62
+ Removed pngprefs.h and MMX from makefiles
+
+Version 1.4.0beta58 [May 14, 2009]
+ Changed pngw32.def to pngwin.def in makefile.mingw (typo was introduced
+ in beta57).
+ Clarified usage of sig_bit versus sig_bit_p in example.c (Vincent Torri)
+
+Version 1.4.0beta59 [May 15, 2009]
+ Reformated sources in libpng style (3-space intentation, comment format)
+ Fixed typo in libpng docs (PNG_FILTER_AVE should be PNG_FILTER_AVG)
+ Added sections about the git repository and our coding style to the
+ documentation
+ Relocated misplaced #endif in pngwrite.c, sCAL chunk handler.
+
+Version 1.4.0beta60 [May 19, 2009]
+ Conditionally compile png_read_finish_row() which is not used by
+ progressive readers.
+ Added contrib/pngminim/preader to demonstrate building minimal progressive
+ decoder, based on contrib/gregbook with embedded libpng and zlib.
+
+Version 1.4.0beta61 [May 20, 2009]
+ In contrib/pngminim/*, renamed "makefile.std" to "makefile", since there
+ is only one makefile in those directories, and revised the README files
+ accordingly.
+ More reformatting of comments, mostly to capitalize sentences.
+
+Version 1.4.0beta62 [June 2, 2009]
+ Added "#define PNG_NO_WRITE_SWAP" to contrib/pngminim/encoder/pngusr.h
+ and "define PNG_NO_READ_SWAP" to decoder/pngusr.h and preader/pngusr.h
+ Reformatted several remaining "else statement" into two lines.
+ Added a section to the libpng documentation about using png_get_io_ptr()
+ in configure scripts to detect the presence of libpng.
+
+Version 1.4.0beta63 [June 15, 2009]
+ Revised libpng*.txt and libpng.3 to mention calling png_set_IHDR()
+ multiple times and to specify the sample order in the tRNS chunk,
+ because the ISO PNG specification has a typo in the tRNS table.
+ Changed several PNG_UNKNOWN_CHUNK_SUPPORTED to
+ PNG_HANDLE_AS_UNKNOWN_SUPPORTED, to make the png_set_keep mechanism
+ available for ignoring known chunks even when not saving unknown chunks.
+ Adopted preference for consistent use of "#ifdef" and "#ifndef" versus
+ "#if defined()" and "if !defined()" where possible.
+
+Version 1.4.0beta64 [June 24, 2009]
+ Eliminated PNG_LEGACY_SUPPORTED code.
+ Moved the various unknown chunk macro definitions outside of the
+ PNG_READ|WRITE_ANCILLARY_CHUNK_SUPPORTED blocks.
+
+Version 1.4.0beta65 [June 26, 2009]
+ Added a reference to the libpng license in each file.
+
+Version 1.4.0beta66 [June 27, 2009]
+ Refer to the libpng license instead of the libpng license in each file.
+
+Version 1.4.0beta67 [July 6, 2009]
+ Relocated INVERT_ALPHA within png_read_png() and png_write_png().
+ Added high-level API transform PNG_TRANSFORM_GRAY_TO_RGB.
+ Added an "xcode" project to the projects directory (Alam Arias).
+
+Version 1.4.0beta68 [July 19, 2009]
+ Avoid some tests in filter selection in pngwutil.c
+
+Version 1.4.0beta69 [July 25, 2009]
+ Simplified the new filter-selection test. This runs faster in the
+ common "PNG_ALL_FILTERS" and PNG_FILTER_NONE cases.
+ Removed extraneous declaration from the new call to png_read_gray_to_rgb()
+ (bug introduced in libpng-1.4.0beta67).
+ Fixed up xcode project (Alam Arias)
+ Added a prototype for png_64bit_product() in png.c
+
+Version 1.4.0beta70 [July 27, 2009]
+ Avoid a possible NULL dereference in debug build, in png_set_text_2().
+ (bug introduced in libpng-0.95, discovered by Evan Rouault)
+
+Version 1.4.0beta71 [July 29, 2009]
+ Rebuilt configure scripts with autoconf-2.64.
+
+Version 1.4.0beta72 [August 1, 2009]
+ Replaced *.tar.lzma with *.tar.xz in distribution. Get the xz codec
+ from <http://tukaani.org/xz>.
+
+Version 1.4.0beta73 [August 1, 2009]
+ Reject attempt to write iCCP chunk with negative embedded profile length
+ (JD Chen) (CVE-2009-5063).
+
+Version 1.4.0beta74 [August 8, 2009]
+ Changed png_ptr and info_ptr member "trans" to "trans_alpha".
+
+Version 1.4.0beta75 [August 21, 2009]
+ Removed an extra png_debug() recently added to png_write_find_filter().
+ Fixed incorrect #ifdef in pngset.c regarding unknown chunk support.
+
+Version 1.4.0beta76 [August 22, 2009]
+ Moved an incorrectly located test in png_read_row() in pngread.c
+
+Version 1.4.0beta77 [August 27, 2009]
+ Removed lpXYZ.tar.bz2 (with CRLF), KNOWNBUG, libpng-x.y.z-KNOWNBUG.txt,
+ and the "noconfig" files from the distribution.
+ Moved CMakeLists.txt from scripts into the main libpng directory.
+ Various bugfixes and improvements to CMakeLists.txt (Philip Lowman)
+
+Version 1.4.0beta78 [August 31, 2009]
+ Converted all PNG_NO_* tests to PNG_*_SUPPORTED everywhere except pngconf.h
+ Eliminated PNG_NO_FREE_ME and PNG_FREE_ME_SUPPORTED macros.
+ Use png_malloc plus a loop instead of png_calloc() to initialize
+ row_pointers in png_read_png().
+
+Version 1.4.0beta79 [September 1, 2009]
+ Eliminated PNG_GLOBAL_ARRAYS and PNG_LOCAL_ARRAYS; always use local arrays.
+ Eliminated PNG_CALLOC_SUPPORTED macro and always provide png_calloc().
+
+Version 1.4.0beta80 [September 17, 2009]
+ Removed scripts/libpng.icc
+ Changed typecast of filler from png_byte to png_uint_16 in png_set_filler().
+ (Dennis Gustafsson)
+ Fixed typo introduced in beta78 in pngtest.c ("#if def " should be "#ifdef ")
+
+Version 1.4.0beta81 [September 23, 2009]
+ Eliminated unused PNG_FLAG_FREE_* defines from pngpriv.h
+ Expanded TAB characters in pngrtran.c
+ Removed PNG_CONST from all "PNG_CONST PNG_CHNK" declarations to avoid
+ compiler complaints about doubly declaring things "const".
+ Changed all "#if [!]defined(X)" to "if[n]def X" where possible.
+ Eliminated unused png_ptr->row_buf_size
+
+Version 1.4.0beta82 [September 25, 2009]
+ Moved redundant IHDR checking into new png_check_IHDR() in png.c
+ and report all errors found in the IHDR data.
+ Eliminated useless call to png_check_cHRM() from pngset.c
+
+Version 1.4.0beta83 [September 25, 2009]
+ Revised png_check_IHDR() to eliminate bogus complaint about filter_type.
+
+Version 1.4.0beta84 [September 30, 2009]
+ Fixed some inconsistent indentation in pngconf.h
+ Revised png_check_IHDR() to add a test for width variable less than 32-bit.
+
+Version 1.4.0beta85 [October 1, 2009]
+ Revised png_check_IHDR() again, to check info_ptr members instead of
+ the contents of the returned parameters.
+
+Version 1.4.0beta86 [October 9, 2009]
+ Updated the "xcode" project (Alam Arias).
+ Eliminated a shadowed declaration of "pp" in png_handle_sPLT().
+
+Version 1.4.0rc01 [October 19, 2009]
+ Trivial cosmetic changes.
+
+Version 1.4.0beta87 [October 30, 2009]
+ Moved version 1.4.0 back into beta.
+
+Version 1.4.0beta88 [October 30, 2009]
+ Revised libpng*.txt section about differences between 1.2.x and 1.4.0
+ because most of the new features have now been ported back to 1.2.41
+
+Version 1.4.0beta89 [November 1, 2009]
+ More bugfixes and improvements to CMakeLists.txt (Philip Lowman)
+ Removed a harmless extra png_set_invert_alpha() from pngwrite.c
+ Apply png_user_chunk_cache_max within png_decompress_chunk().
+ Merged libpng-1.2.41.txt with libpng-1.4.0.txt where appropriate.
+
+Version 1.4.0beta90 [November 2, 2009]
+ Removed all remaining WIN32_WCE #ifdefs except those involving the
+ time.h "tm" structure
+
+Version 1.4.0beta91 [November 3, 2009]
+ Updated scripts/pngw32.def and projects/wince/png32ce.def
+ Copied projects/wince/png32ce.def to the scripts directory.
+ Added scripts/makefile.wce
+ Patched ltmain.sh for wince support.
+ Added PNG_CONVERT_tIME_SUPPORTED macro.
+
+Version 1.4.0beta92 [November 4, 2009]
+ Make inclusion of time.h in pngconf.h depend on PNG_CONVERT_tIME_SUPPORTED
+ Make #define PNG_CONVERT_tIME_SUPPORTED depend on PNG_WRITE_tIME_SUPPORTED
+ Revised libpng*.txt to describe differences from 1.2.40 to 1.4.0 (instead
+ of differences from 1.2.41 to 1.4.0)
+
+Version 1.4.0beta93 [November 7, 2009]
+ Added PNG_DEPSTRUCT, PNG_DEPRECATED, PNG_USE_RESULT, PNG_NORETURN, and
+ PNG_ALLOCATED macros to detect deprecated direct access to the
+ png_struct or info_struct members and other deprecated usage in
+ applications (John Bowler).
+ Updated scripts/makefile* to add "-DPNG_CONFIGURE_LIBPNG" to CFLAGS,
+ to prevent warnings about direct access to png structs by libpng
+ functions while building libpng. They need to be tested, especially
+ those using compilers other than gcc.
+ Updated projects/visualc6 and visualc71 with "/d PNG_CONFIGURE_LIBPNG".
+ They should work but still need to be updated to remove
+ references to pnggccrd.c or pngvcrd.c and ASM building.
+ Added README.txt to the beos, cbuilder5, netware, and xcode projects warning
+ that they need to be updated, to remove references to pnggccrd.c and
+ pngvcrd.c and to depend on pngpriv.h
+ Removed three direct references to read_info_ptr members in pngtest.c
+ that were detected by the new PNG_DEPSTRUCT macro.
+ Moved the png_debug macro definitions and the png_read_destroy(),
+ png_write_destroy() and png_far_to_near() prototypes from png.h
+ to pngpriv.h (John Bowler)
+ Moved the synopsis lines for png_read_destroy(), png_write_destroy()
+ png_debug(), png_debug1(), and png_debug2() from libpng.3 to libpngpf.3.
+
+Version 1.4.0beta94 [November 9, 2009]
+ Removed the obsolete, unused pnggccrd.c and pngvcrd.c files.
+ Updated CMakeLists.txt to add "-DPNG_CONFIGURE_LIBPNG" to the definitions.
+ Removed dependency of pngtest.o on pngpriv.h in the makefiles.
+ Only #define PNG_DEPSTRUCT, etc. in pngconf.h if not already defined.
+
+Version 1.4.0beta95 [November 10, 2009]
+ Changed png_check_sig() to !png_sig_cmp() in contrib programs.
+ Added -DPNG_CONFIGURE_LIBPNG to contrib/pngminm/*/makefile
+ Changed png_check_sig() to !png_sig_cmp() in contrib programs.
+ Corrected the png_get_IHDR() call in contrib/gregbook/readpng2.c
+ Changed pngminim/*/gather.sh to stop trying to remove pnggccrd.c and pngvcrd.c
+ Added dependency on pngpriv.h in contrib/pngminim/*/makefile
+
+Version 1.4.0beta96 [November 12, 2009]
+ Renamed scripts/makefile.wce to scripts/makefile.cegcc
+ Revised Makefile.am to use libpng.sys while building libpng.so
+ so that only PNG_EXPORT functions are exported.
+ Removed the deprecated png_check_sig() function/macro.
+ Removed recently removed function names from scripts/*.def
+ Revised pngtest.png to put chunks in the same order written by pngtest
+ (evidently the same change made in libpng-1.0beta54 was lost).
+ Added PNG_PRIVATE macro definition in pngconf.h for possible future use.
+
+Version 1.4.0beta97 [November 13, 2009]
+ Restored pngtest.png to the libpng-1.4.0beta7 version.
+ Removed projects/beos and netware.txt; no one seems to be supporting them.
+ Revised Makefile.in
+
+Version 1.4.0beta98 [November 13, 2009]
+ Added the "xcode" project to zip distributions,
+ Fixed a typo in scripts/pngwin.def introduced in beta97.
+
+Version 1.4.0beta99 [November 14, 2009]
+ Moved libpng-config.in and libpng.pc-configure.in out of the scripts
+ directory, to libpng-config.in and libpng-pc.in, respectively, and
+ modified Makefile.am and configure.ac accordingly. Now "configure"
+ needs nothing from the "scripts" directory.
+ Avoid redefining PNG_CONST in pngconf.h
+
+Version 1.4.0beta100 [November 14, 2009]
+ Removed ASM builds from projects/visualc6 and projects/visualc71
+ Removed scripts/makefile.nommx and makefile.vcawin32
+ Revised CMakeLists.txt to account for new location of libpng-config.in
+ and libpng-pc.in
+ Updated INSTALL to reflect removal and relocation of files.
+
+Version 1.4.0beta101 [November 14, 2009]
+ Restored the binary files (*.jpg, *.png, some project files) that were
+ accidentally deleted from the zip and 7z distributions when the xcode
+ project was added.
+
+Version 1.4.0beta102 [November 18, 2009]
+ Added libpng-config.in and libpng-pc.in to the zip and 7z distributions.
+ Fixed a typo in projects/visualc6/pngtest.dsp, introduced in beta100.
+ Moved descriptions of makefiles and other scripts out of INSTALL into
+ scripts/README.txt
+ Updated the copyright year in scripts/pngwin.rc from 2006 to 2009.
+
+Version 1.4.0beta103 [November 21, 2009]
+ Removed obsolete comments about ASM from projects/visualc71/README_zlib.txt
+ Align row_buf on 16-byte boundary in memory.
+ Restored the PNG_WRITE_FLUSH_AFTER_IEND_SUPPORTED guard around the call
+ to png_flush() after png_write_IEND(). See 1.4.0beta32, 1.4.0beta50
+ changes above and 1.2.30, 1.2.30rc01 and rc03 in 1.2.41 CHANGES. Someone
+ needs this feature.
+ Make the 'png_jmpbuf' macro expand to a call that records the correct
+ longjmp function as well as returning a pointer to the setjmp
+ jmp_buf buffer, and marked direct access to jmpbuf 'deprecated'.
+ (John Bowler)
+
+Version 1.4.0beta104 [November 22, 2009]
+ Removed png_longjmp_ptr from scripts/*.def and libpng.3
+ Rebuilt configure scripts with autoconf-2.65
+
+Version 1.4.0beta105 [November 25, 2009]
+ Use fast integer PNG_DIVIDE_BY_255() or PNG_DIVIDE_BY_65535()
+ to accomplish alpha premultiplication when
+ PNG_READ_COMPOSITE_NODIV_SUPPORTED is defined.
+ Changed "/255" to "/255.0" in background calculations to make it clear
+ that the 255 is used as a double.
+
+Version 1.4.0beta106 [November 27, 2009]
+ Removed premultiplied alpha feature.
+
+Version 1.4.0beta107 [December 4, 2009]
+ Updated README
+ Added "#define PNG_NO_PEDANTIC_WARNINGS" in the libpng source files.
+ Removed "-DPNG_CONFIGURE_LIBPNG" from the makefiles and projects.
+ Revised scripts/makefile.netbsd, makefile.openbsd, and makefile.sco
+ to put png.h and pngconf.h in $prefix/include, like the other scripts,
+ instead of in $prefix/include/libpng. Also revised makefile.sco
+ to put them in $prefix/include/libpng15 instead of in
+ $prefix/include/libpng/libpng15.
+
+Version 1.4.0beta108 [December 11, 2009]
+ Removed leftover "-DPNG_CONFIGURE_LIBPNG" from contrib/pngminim/*/makefile
+ Relocated png_do_chop() to its original position in pngrtran.c; the
+ change in version 1.2.41beta08 caused transparency to be handled wrong
+ in some 16-bit datastreams (Yusaku Sugai).
+
+Version 1.4.0beta109 [December 13, 2009]
+ Added "bit_depth" parameter to the private png_build_gamma_table() function.
+ Pass bit_depth=8 to png_build_gamma_table() when bit_depth is 16 but the
+ PNG_16_TO_8 transform has been set, to avoid unnecessary build of 16-bit
+ tables.
+
+Version 1.4.0rc02 [December 20, 2009]
+ Declared png_cleanup_needed "volatile" in pngread.c and pngwrite.c
+
+Version 1.4.0rc03 [December 22, 2009]
+ Renamed libpng-pc.in back to libpng.pc.in and revised CMakeLists.txt
+ (revising the change in 1.4.0beta99)
+
+Version 1.4.0rc04 [December 25, 2009]
+ Swapped PNG_UNKNOWN_CHUNKS_SUPPORTED and PNG_HANDLE_AS_UNKNOWN_SUPPORTED
+ in pngset.c to be consistent with other changes in version 1.2.38.
+
+Version 1.4.0rc05 [December 25, 2009]
+ Changed "libpng-pc.in" to "libpng.pc.in" in configure.ac, configure, and
+ Makefile.in to be consistent with changes in libpng-1.4.0rc03
+
+Version 1.4.0rc06 [December 29, 2009]
+ Reverted the gamma_table changes from libpng-1.4.0beta109.
+ Fixed some indentation errors.
+
+Version 1.4.0rc07 [January 1, 2010]
+ Revised libpng*.txt and libpng.3 about 1.2.x->1.4.x differences.
+ Use png_calloc() instead of png_malloc(); png_memset() in pngrutil.c
+ Update copyright year to 2010.
+
+Version 1.4.0rc08 [January 2, 2010]
+ Avoid deprecated references to png_ptr-io_ptr and png_ptr->error_ptr
+ in pngtest.c
+
+Version 1.4.0 [January 3, 2010]
+ No changes.
+
+Version 1.4.1beta01 [January 8, 2010]
+ Updated CMakeLists.txt for consistent indentation and to avoid an
+ unclosed if-statement warning (Philip Lowman).
+ Revised Makefile.am and Makefile.in to remove references to Y2KINFO,
+ KNOWNBUG, and libpng.la (Robert Schwebel).
+ Revised the makefiles to install the same files and symbolic
+ links as configure, except for libpng.la and libpng14.la.
+ Make png_set|get_compression_buffer_size() available even when
+ PNG_WRITE_SUPPORTED is not enabled.
+ Revised Makefile.am and Makefile.in to simplify their maintenance.
+ Revised scripts/makefile.linux to install a link to libpng14.so.14.1
+
+Version 1.4.1beta02 [January 9, 2010]
+ Revised the rest of the makefiles to install a link to libpng14.so.14.1
+
+Version 1.4.1beta03 [January 10, 2010]
+ Removed png_set_premultiply_alpha() from scripts/*.def
+
+Version 1.4.1rc01 [January 16, 2010]
+ No changes.
+
+Version 1.4.1beta04 [January 23, 2010]
+ Revised png_decompress_chunk() to improve speed and memory usage when
+ decoding large chunks.
+ Added png_set|get_chunk_malloc_max() functions.
+
+Version 1.4.1beta05 [January 26, 2010]
+ Relocated "int k" declaration in pngtest.c to minimize its scope.
+
+Version 1.4.1beta06 [January 28, 2010]
+ Revised png_decompress_chunk() to use a two-pass method suggested by
+ John Bowler.
+
+Version 1.4.1beta07 [February 6, 2010]
+ Folded some long lines in the source files.
+ Added defineable PNG_USER_CHUNK_CACHE_MAX, PNG_USER_CHUNK_MALLOC_MAX,
+ and a PNG_USER_LIMITS_SUPPORTED flag.
+ Eliminated use of png_ptr->irowbytes and reused the slot in png_ptr as
+ png_ptr->png_user_chunk_malloc_max.
+ Revised png_push_save_buffer() to do fewer but larger png_malloc() calls.
+
+Version 1.4.1beta08 [February 6, 2010]
+ Minor cleanup and updating of dates and copyright year.
+
+Version 1.5.0beta01 [February 7, 2010]
+ Moved declaration of png_struct into private pngstruct.h and png_info
+ into pnginfo.h
+
+Version 1.4.1beta09 and 1.5.0beta02 [February 7, 2010]
+ Reverted to original png_push_save_buffer() code.
+
+Version 1.4.1beta10 and 1.5.0beta03 [February 8, 2010]
+ Return allocated "old_buffer" in png_push_save_buffer() before
+ calling png_error(), to avoid a potential memory leak.
+ Updated configure script to use SO number 15.
+
+Version 1.5.0beta04 [February 9, 2010]
+ Removed malformed "incomplete struct declaration" of png_info from png.h
+
+Version 1.5.0beta05 [February 12, 2010]
+ Removed PNG_DEPSTRUCT markup in pngstruct.h and pnginfo.h, and undid the
+ linewrapping that it entailed.
+ Revised comments in pngstruct.h and pnginfo.h and added pointers to
+ the libpng license.
+ Changed PNG_INTERNAL to PNG_EXPOSE_INTERNAL_STRUCTURES
+ Removed the cbuilder5 project, which has not been updated to 1.4.0.
+
+Version 1.4.1beta12 and 1.5.0beta06 [February 14, 2010]
+ Fixed type declaration of png_get_chunk_malloc_max() in pngget.c (Daisuke
+ Nishikawa)
+
+Version 1.5.0beta07 [omitted]
+
+Version 1.5.0beta08 [February 19, 2010]
+ Changed #ifdef PNG_NO_STDIO_SUPPORTED to #ifdef PNG_NO_CONSOLE_IO_SUPPORTED
+ wherever png_snprintf() is used to construct error and warning messages.
+ Noted in scripts/makefile.mingw that it expects to be run under MSYS.
+ Removed obsolete unused MMX-querying support from contrib/gregbook
+ Added exported png_longjmp() function.
+ Removed the AIX redefinition of jmpbuf in png.h
+ Added -D_ALLSOURCE in configure.ac, makefile.aix, and CMakeLists.txt
+ when building on AIX.
+
+Version 1.5.0beta09 [February 19, 2010]
+ Removed -D_ALLSOURCE from configure.ac, makefile.aix, and CMakeLists.txt.
+ Changed the name of png_ptr->jmpbuf to png_ptr->png_jmpbuf in pngstruct.h
+
+Version 1.5.0beta10 [February 25, 2010]
+ Removed unused gzio.c from contrib/pngminim gather and makefile scripts
+ Removed replacement error handlers from contrib/gregbook. Because of
+ the new png_longjmp() function they are no longer needed.
+
+Version 1.5.0beta11 [March 6, 2010]
+ Removed checking for already-included setjmp.h from pngconf.h
+ Fixed inconsistent indentations and made numerous cosmetic changes.
+ Revised the "SEE ALSO" style of libpng.3, libpngpf.3, and png.5
+
+Version 1.5.0beta12 [March 9, 2010]
+ Moved "#include png.h" inside pngpriv.h and removed "#include png.h" from
+ the source files, along with "#define PNG_EXPOSE_INTERNAL_STRUCTURES"
+ and "#define PNG_NO_PEDANTIC_WARNINGS" (John Bowler).
+ Created new pngdebug.h and moved debug definitions there.
+
+Version 1.5.0beta13 [March 10, 2010]
+ Protect pngstruct.h, pnginfo.h, and pngdebug.h from being included twice.
+ Revise the "#ifdef" blocks in png_inflate() so it will compile when neither
+ PNG_USER_CHUNK_MALLOC_MAX nor PNG_SET_CHUNK_MALLOC_LIMIT_SUPPORTED
+ is defined.
+ Removed unused png_measure_compressed_chunk() from pngpriv.h and libpngpf.3
+ Moved the 'config.h' support from pngconf.h to pngpriv.h
+ Removed PNGAPI from the png_longjmp_ptr typedef.
+ Eliminated dependence of pngtest.c on the private pngdebug.h file.
+ Make all png_debug macros into *unterminated* statements or
+ expressions (i.e. a trailing ';' must always be added) and correct
+ the format statements in various png_debug messages.
+
+Version 1.5.0beta14 [March 14, 2010]
+ Removed direct access to png_ptr->io_ptr from the Windows code in pngtest.c
+ Revised Makefile.am to account for recent additions and replacements.
+ Corrected CE and OS/2 DEF files (scripts/png*def) for symbols removed and
+ added ordinal numbers to the Windows DEF file and corrected the duplicated
+ ordinal numbers on CE symbols that are commented out.
+ Added back in export symbols that can be present in the Windows build but
+ are disabled by default.
+ PNG_EXPORT changed to include an 'ordinal' field for DEF file generation.
+ PNG_CALLBACK added to make callback definitions uniform. PNGAPI split
+ into PNGCAPI (base C form), PNGAPI (exports) and PNGCBAPI (callbacks),
+ and appropriate changes made to all files. Cygwin builds re-hinged to
+ allow procedure call standard changes and to remove the need for the DEF
+ file (fixes build on Cygwin).
+ Enabled 'attribute' warnings that are relevant to library APIs and callbacks.
+ Changed rules for generation of the various symbol files and added a new
+ rule for a DEF file (which is also added to the distribution).
+ Updated the symbol file generation to stop it adding spurious spaces
+ to EOL (coming from preprocessor macro expansion). Added a facility
+ to join tokens in the output and rewrite *.dfn to use this.
+ Eliminated scripts/*.def in favor of libpng.def; updated projects/visualc71
+ and removed scripts/makefile.cygwin.
+ Made PNG_BUILD_DLL safe: it can be set whenever a DLL is being built.
+ Removed the include of sys/types.h - apparently unnecessary now on the
+ platforms on which it happened (all but Mac OS and RISC OS).
+ Moved the Mac OS test into pngpriv.h (the only place it is used.)
+
+Version 1.5.0beta15 [March 17, 2010]
+ Added symbols.chk target to Makefile.am to validate the symbols in png.h
+ against the new DEF file scripts/symbols.def.
+ Changed the default DEF file back to pngwin.def.
+ Removed makefile.mingw.
+ Eliminated PNG_NO_EXTERN and PNG_ALL_EXTERN
+
+Version 1.5.0beta16 [April 1, 2010]
+ Make png_text_struct independent of PNG_iTXt_SUPPORTED, so that
+ fields are initialized in all configurations. The READ/WRITE
+ macros (PNG_(READ|WRITE)_iTXt_SUPPORTED) still function as
+ before to disable code to actually read or write iTXt chunks
+ and iTXt_SUPPORTED can be used to detect presence of either
+ read or write support (but it is probably better to check for
+ the one actually required - read or write.)
+ Combined multiple png_warning() calls for a single error.
+ Restored the macro definition of png_check_sig().
+
+Version 1.5.0beta17 [April 17, 2010]
+ Added some "(long)" typecasts to printf calls in png_handle_cHRM().
+ Documented the fact that png_set_dither() was disabled since libpng-1.4.0.
+ Reenabled png_set_dither() but renamed it to png_set_quantize() to reflect
+ more accurately what it actually does. At the same time, renamed
+ the PNG_DITHER_[RED,GREEN_BLUE]_BITS macros to
+ PNG_QUANTIZE_[RED,GREEN,BLUE]_BITS.
+ Added some "(long)" typecasts to printf calls in png_handle_cHRM().
+ Freeze build-time only configuration in the build.
+ In all prior versions of libpng most configuration options
+ controlled by compiler #defines had to be repeated by the
+ application code that used libpng. This patch changes this
+ so that compilation options that can only be changed at build
+ time are frozen in the build. Options that are compiler
+ dependent (and those that are system dependent) are evaluated
+ each time - pngconf.h holds these. Options that can be changed
+ per-file in the application are in png.h. Frozen options are
+ in the new installed header file pnglibconf.h (John Bowler)
+ Removed the xcode project because it has not been updated to work
+ with libpng-1.5.0.
+ Removed the ability to include optional pngusr.h
+
+Version 1.5.0beta18 [April 17, 2010]
+ Restored the ability to include optional pngusr.h
+ Moved replacements for png_error() and png_warning() from the
+ contrib/pngminim project to pngerror.c, for use when warnings or
+ errors are disabled via PNG_NO_WARN or PNG_NO_ERROR_TEXT, to avoid
+ storing unneeded error/warning text.
+ Updated contrib/pngminim project to work with the new pnglibconf.h
+ Added some PNG_NO_* defines to contrib/pngminim/*/pngusr.h to save space.
+
+Version 1.5.0beta19 [April 24, 2010]
+ Added PNG_{READ,WRITE}_INT_FUNCTIONS_SUPPORTED. This allows the functions
+ to read and write ints to be disabled independently of PNG_USE_READ_MACROS,
+ which allows libpng to be built with the functions even though the default
+ is to use the macros - this allows applications to choose at app build
+ time whether or not to use macros (previously impossible because the
+ functions weren't in the default build.)
+ Changed Windows calling convention back to __cdecl for API functions.
+ For Windows/x86 platforms only:
+ __stdcall is no longer needed for Visual Basic, so libpng-1.5.0 uses
+ __cdecl throughout (both API functions and callbacks) on Windows/x86
+ platforms.
+ Replaced visualc6 and visualc71 projects with new vstudio project
+ Relaxed the overly-restrictive permissions of some files.
+
+Version 1.5.0beta20 [April 24, 2010]
+ Relaxed more overly-restrictive permissions of some files.
+
+Version 1.5.0beta21 [April 27, 2010]
+ Removed some unwanted binary bytes and changed CRLF to NEWLINE in the new
+ vstudio project files, and some trivial editing of some files in the
+ scripts directory.
+ Set PNG_NO_READ_BGR, PNG_NO_IO_STATE, and PNG_NO_TIME_RFC1123 in
+ contrib/pngminim/decoder/pngusr.h to make a smaller decoder application.
+
+Version 1.5.0beta22 [April 28, 2010]
+ Fixed dependencies of GET_INT_32 - it does not require READ_INT_FUNCTIONS
+ because it has a macro equivalent.
+ Improved the options.awk script; added an "everything off" option.
+ Revised contrib/pngminim to use the "everything off" option in pngusr.dfa.
+
+Version 1.5.0beta23 [April 29, 2010]
+ Corrected PNG_REMOVED macro to take five arguments.
+ The macro was documented with two arguments (name,ordinal), however
+ the symbol checking .dfn files assumed five arguments. The five
+ argument form seems more useful so it is changed to that.
+ Corrected PNG_UNKNOWN_CHUNKS_SUPPORTED to PNG_HANDLE_AS_UNKNOWN_SUPPORTED
+ in gregbook/readpng2.c
+ Corrected protection of png_get_user_transform_ptr. The API declaration in
+ png.h is removed if both READ and WRITE USER_TRANSFORM are turned off
+ but was left defined in pngtrans.c
+ Added logunsupported=1 to cause pnglibconf.h to document disabled options.
+ This makes the installed pnglibconf.h more readable but causes no
+ other change. The intention is that users of libpng will find it
+ easier to understand if an API they need is missing.
+ Include png_reset_zstream() in png.c only when PNG_READ_SUPPORTED is defined.
+ Removed dummy_inflate.c from contrib/pngminim/encoder
+ Removed contrib/pngminim/*/gather.sh; gathering is now done in the makefile.
+
+Version 1.5.0beta24 [May 7, 2010]
+ Use bitwise "&" instead of arithmetic mod in pngrutil.c calculation of the
+ offset of the png_ptr->rowbuf pointer into png_ptr->big_row_buf.
+ Added more blank lines for readability.
+
+Version 1.5.0beta25 [June 18, 2010]
+ In pngpread.c: png_push_have_row() add check for new_row > height
+ Removed the now-redundant check for out-of-bounds new_row from example.c
+
+Version 1.5.0beta26 [June 18, 2010]
+ In pngpread.c: png_push_process_row() add check for too many rows.
+
+Version 1.5.0beta27 [June 18, 2010]
+ Removed the check added in beta25 as it is now redundant.
+
+Version 1.5.0beta28 [June 20, 2010]
+ Rewrote png_process_IDAT_data to consistently treat extra data as warnings
+ and handle end conditions more cleanly.
+ Removed the new (beta26) check in png_push_process_row().
+
+Version 1.5.0beta29 [June 21, 2010]
+ Revised scripts/options.awk to work on Sunos (but still doesn't work)
+ Added comment to options.awk and contrib/pngminim/*/makefile to try nawk.
+
+Version 1.5.0beta30 [June 22, 2010]
+ Stop memory leak when reading a malformed sCAL chunk.
+
+Version 1.5.0beta31 [June 26, 2010]
+ Revised pngpread.c patch of beta28 to avoid an endless loop.
+ Removed some trailing blanks.
+
+Version 1.5.0beta32 [June 26, 2010]
+ Removed leftover scripts/options.patch and scripts/options.rej
+
+Version 1.5.0beta33 [July 6, 3010]
+ Made FIXED and FLOATING options consistent in the APIs they enable and
+ disable. Corrected scripts/options.awk to handle both command line
+ options and options specified in the .dfa files.
+ Changed char *msg to PNG_CONST char *msg in pngrutil.c
+ Make png_set_sRGB_gAMA_and_cHRM set values using either the fixed or
+ floating point APIs, but not both.
+ Reversed patch to remove error handler when the jmp_buf is stored in the
+ main program structure, not the png_struct.
+ The error handler is needed because the default handler in libpng will
+ always use the jmp_buf in the library control structure; this is never
+ set. The gregbook code is a useful example because, even though it
+ uses setjmp/longjmp, it shows how error handling can be implemented
+ using control mechanisms not directly supported by libpng. The
+ technique will work correctly with mechanisms such as Microsoft
+ Structure Exceptions or C++ exceptions (compiler willing - note that gcc
+ does not by default support interworking of C and C++ error handling.)
+ Reverted changes to call png_longjmp in contrib/gregbook where it is not
+ appropriate. If mainprog->jmpbuf is used by setjmp, then png_longjmp
+ cannot be used.
+ Changed "extern PNG_EXPORT" to "PNG_EXPORT" in png.h (Jan Nijtmans)
+ Changed "extern" to "PNG_EXTERN" in pngpriv.h (except for the 'extern "C" {')
+
+Version 1.5.0beta34 [July 12, 2010]
+ Put #ifndef PNG_EXTERN, #endif around the define PNG_EXTERN in pngpriv.h
+
+Version 1.5.0beta35 [July 24, 2010]
+ Removed some newly-added TAB characters.
+ Added -DNO_PNG_SNPRINTF to CFLAGS in scripts/makefile.dj2
+ Moved the definition of png_snprintf() outside of the enclosing
+ #ifdef blocks in pngconf.h
+
+Version 1.5.0beta36 [July 29, 2010]
+ Patches by John Bowler:
+ Fixed point APIs are now supported throughout (no missing APIs).
+ Internal fixed point arithmetic support exists for all internal floating
+ point operations.
+ sCAL validates the floating point strings it is passed.
+ Safe, albeit rudimentary, Watcom support is provided by PNG_API_RULE==2
+ Two new APIs exist to get the number of passes without turning on the
+ PNG_INTERLACE transform and to get the number of rows in the current
+ pass.
+ A new test program, pngvalid.c, validates the gamma code.
+ Errors in the 16-bit gamma correction (overflows) have been corrected.
+ cHRM chunk testing is done consistently (previously the floating point
+ API bypassed it, because the test really didn't work on FP, now the test
+ is performed on the actual values to be stored in the PNG file so it
+ works in the FP case too.)
+ Most floating point APIs now simply call the fixed point APIs after
+ converting the values to the fixed point form used in the PNG file.
+ The standard headers no longer include zlib.h, which is currently only
+ required for pngstruct.h and can therefore be internal.
+ Revised png_get_int_32 to undo the PNG two's complement representation of
+ negative numbers.
+
+Version 1.5.0beta37 [July 30, 2010]
+ Added a typecast in png_get_int_32() in png.h and pngrutil.h to avoid
+ a compiler warning.
+ Replaced oFFs 0,0 with oFFs -10,20 in pngtest.png
+
+Version 1.5.0beta38 [July 31, 2010]
+ Implemented remaining "_fixed" functions.
+ Corrected a number of recently introduced warnings mostly resulting from
+ safe but uncast assignments to shorter integers. Also added a zlib
+ VStudio release library project because the latest zlib Official Windows
+ build does not include such a thing.
+ Revised png_get_int_16() to be similar to png_get_int_32().
+ Restored projects/visualc71.
+
+Version 1.5.0beta39 [August 2, 2010]
+ VisualC/GCC warning fixes, VisualC build fixes
+ The changes include support for function attributes in VC in addition to
+ those already present in GCC - necessary because without these some
+ warnings are unavoidable. Fixes include signed/unsigned fixes in
+ pngvalid and checks with gcc -Wall -Wextra -Wunused.
+ VC requires function attributes on function definitions as well as
+ declarations, PNG_FUNCTION has been added to enable this and the
+ relevant function definitions changed.
+
+Version 1.5.0beta40 [August 6, 2010]
+ Correct use of _WINDOWS_ in pngconf.h
+ Removed png_mem_ #defines; they are no longer used.
+ Added the sRGB chunk to pngtest.png
+
+Version 1.5.0beta41 [August 11, 2010]
+ Added the cHRM chunk to pngtest.png
+ Don't try to use version-script with cygwin/mingw.
+ Revised contrib/gregbook to work under cygwin/mingw.
+
+Version 1.5.0beta42 [August 18, 2010]
+ Add .dll.a to the list of extensions to be symlinked by Makefile.am (Yaakov)
+ Made all API functions that have const arguments and constant string
+ literal pointers declare them (John Bowler).
+
+Version 1.5.0beta43 [August 20, 2010]
+ Removed spurious tabs, shorten long lines (no source change)
+ Also added scripts/chkfmt to validate the format of all the files that can
+ reasonably be validated (it is suggested to run "make distclean" before
+ checking, because some machine generated files have long lines.)
+ Reformatted the CHANGES file to be more consistent throughout.
+ Made changes to address various issues identified by GCC, mostly
+ signed/unsigned and shortening problems on assignment but also a few
+ difficult to optimize (for GCC) loops.
+ Fixed non-GCC fixed point builds. In png.c a declaration was misplaced
+ in an earlier update. Fixed to declare the auto variables at the head.
+ Use cexcept.h in pngvalid.c.
+
+Version 1.5.0beta44 [August 24, 2010]
+ Updated CMakeLists.txt to use CMAKE_INSTALL_LIBDIR variable; useful for
+ installing libpng in /usr/lib64 (Funda Wang).
+ Revised CMakeLists.txt to put the man pages in share/man/man* not man/man*
+ Revised CMakeLists.txt to make symlinks instead of copies when installing.
+ Changed PNG_LIB_NAME from pngNN to libpngNN in CMakeLists.txt (Philip Lowman)
+ Implemented memory checks within pngvalid
+ Reformatted/rearranged pngvalid.c to assist use of progressive reader.
+ Check interlaced images in pngvalid
+ Clarified pngusr.h comments in pnglibconf.dfa
+ Simplified the pngvalid error-handling code now that cexcept.h is in place.
+ Implemented progressive reader in pngvalid.c for standard tests
+ Implemented progressive read in pngvalid.c gamma tests
+ Turn on progressive reader in pngvalid.c by default and tidy code.
+
+Version 1.5.0beta45 [August 26, 2010]
+ Added an explicit make step to projects/vstudio for pnglibconf.h
+ Also corrected zlib.vcxproj into which Visual Studio had introduced
+ what it calls an "authoring error". The change to make pnglibconf.h
+ simply copies the file; in the future it may actually generate the
+ file from scripts/pnglibconf.dfa as the other build systems do.
+ Changed pngvalid to work when floating point APIs are disabled
+ Renamed the prebuilt scripts/pnglibconf.h to scripts/pnglibconf.h.prebuilt
+ Supply default values for PNG_USER_PRIVATEBUILD and PNG_USER_DLLFNAME_POSTFIX
+ in pngpriv.h in case the user neglected to define them in their pngusr.h
+
+Version 1.5.0beta46 [August 28, 2010]
+ Added new private header files to libpng_sources in CMakeLists.txt
+ Added PNG_READ_16BIT, PNG_WRITE_16BIT, and PNG_16BIT options.
+ Added reference to scripts/pnglibconf.h.prebuilt in the visualc71 project.
+
+Version 1.5.0beta47 [September 11, 2010]
+ Fixed a number of problems with 64-bit compilation reported by Visual
+ Studio 2010 (John Bowler).
+
+Version 1.5.0beta48 [October 4, 2010]
+ Updated CMakeLists.txt (Philip Lowman).
+ Revised autogen.sh to recognize and use $AUTOCONF, $AUTOMAKE, $AUTOHEADER,
+ $AUTOPOINT, $ACLOCAL and $LIBTOOLIZE
+ Fixed problem with symbols creation in Makefile.am which was assuming that
+ all versions of ccp write to standard output by default (Martin Banky). The
+ bug was introduced in libpng-1.2.9beta5.
+ Removed unused mkinstalldirs.
+
+Version 1.5.0beta49 [October 8, 2010]
+ Undid Makefile.am revision of 1.5.0beta48.
+
+Version 1.5.0beta50 [October 14, 2010]
+ Revised Makefile.in to account for mkinstalldirs being removed.
+ Added some "(unsigned long)" typecasts in printf statements in pngvalid.c.
+ Suppressed a compiler warning in png_handle_sPLT().
+ Check for out-of-range text compression mode in png_set_text().
+
+Version 1.5.0beta51 [October 15, 2010]
+ Changed embedded dates to "(PENDING RELEASE) in beta releases (and future
+ rc releases) to minimize the difference between releases.
+
+Version 1.5.0beta52 [October 16, 2010]
+ Restored some of the embedded dates (in png.h, png.c, documentation, etc.)
+
+Version 1.5.0beta53 [October 18, 2010]
+ Updated INSTALL to mention using "make maintainer-clean" and to remove
+ obsolete statement about a custom ltmain.sh
+ Disabled "color-tests" by default in Makefile.am so it will work with
+ automake versions earlier than 1.11.1
+ Use document name "libpng-manual.txt" instead of "libpng-<version>.txt"
+ to simplify version differences.
+ Removed obsolete remarks about setjmp handling from INSTALL.
+ Revised and renamed the typedef in png.h and png.c that was designed
+ to catch library and header mismatch.
+
+Version 1.5.0beta54 [November 10, 2010]
+ Require 48 bytes, not 64 bytes, for big_row_buf in overflow checks.
+ Used a consistent structure for the pngget.c functions.
+
+Version 1.5.0beta55 [November 21, 2010]
+ Revised png_get_uint_32, png_get_int_32, png_get_uint_16 (Cosmin)
+ Moved reading of file signature into png_read_sig (Cosmin)
+ Fixed atomicity of chunk header serialization (Cosmin)
+ Added test for io_state in pngtest.c (Cosmin)
+ Added "#!/bin/sh" at the top of contrib/pngminim/*/gather.sh scripts.
+ Changes to remove gcc warnings (John Bowler)
+ Certain optional gcc warning flags resulted in warnings in libpng code.
+ With these changes only -Wconversion and -Wcast-qual cannot be turned on.
+ Changes are trivial rearrangements of code. -Wconversion is not possible
+ for pngrutil.c (because of the widespread use of += et al on variables
+ smaller than (int) or (unsigned int)) and -Wcast-qual is not possible
+ with pngwio.c and pngwutil.c because the 'write' callback and zlib
+ compression both fail to declare their input buffers with 'const'.
+
+Version 1.5.0beta56 [December 7, 2010]
+ Added the private PNG_UNUSED() macro definition in pngpriv.h.
+ Added some commentary about PNG_EXPORT in png.h and pngconf.h
+ Revised PNG_EXPORT() macro and added PNG_EXPORTA() macro, with the
+ objective of simplifying and improving the cosmetic appearance of png.h.
+ Fixed some incorrect "=" macro names in pnglibconf.dfa
+ Included documentation of changes in 1.5.0 from 1.4.x in libpng-manual.txt
+
+Version 1.5.0beta57 [December 9, 2010]
+ Documented the pngvalid gamma error summary with additional comments and
+ print statements.
+ Improved missing symbol handling in checksym.awk; symbols missing in both
+ the old and new files can now be optionally ignored, treated as errors
+ or warnings.
+ Removed references to pngvcrd.c and pnggccrd.c from the vstudio project.
+ Updated "libpng14" to "libpng15" in the visualc71 project.
+ Enabled the strip16 tests in pngvalid.`
+ Don't display test results (except PASS/FAIL) when running "make test".
+ Instead put them in pngtest-log.txt
+ Added "--with-zprefix=<string>" to configure.ac
+ Updated the prebuilt configuration files to autoconf version 2.68
+
+Version 1.5.0beta58 [December 19, 2010]
+ Fixed interlace image handling and add test cases (John Bowler)
+ Fixed the clean rule in Makefile.am to remove pngtest-log.txt
+ Made minor changes to work around warnings in gcc 3.4
+
+Version 1.5.0rc01 [December 27, 2010]
+ No changes.
+
+Version 1.5.0rc02 [December 27, 2010]
+ Eliminated references to the scripts/*.def files in project/visualc71.
+
+Version 1.5.0rc03 [December 28, 2010]
+ Eliminated scripts/*.def and revised Makefile.am accordingly
+
+Version 1.5.0rc04 [December 29, 2010]
+ Fixed bug in background transformation handling in pngrtran.c (it was
+ looking for the flag in png_ptr->transformations instead of in
+ png_ptr->flags) (David Raymond).
+
+Version 1.5.0rc05 [December 31, 2010]
+ Fixed typo in a comment in CMakeLists.txt (libpng14 => libpng15) (Cosmin)
+
+Version 1.5.0rc06 [January 4, 2011]
+ Changed the new configure option "zprefix=string" to "zlib-prefix=string"
+
+Version 1.5.0rc07 [January 4, 2011]
+ Updated copyright year.
+
+Version 1.5.0 [January 6, 2011]
+ No changes.
+
+version 1.5.1beta01 [January 8, 2011]
+ Added description of png_set_crc_action() to the manual.
+ Added a note in the manual that the type of the iCCP profile was changed
+ from png_charpp to png_bytepp in png_get_iCCP(). This change happened
+ in version 1.5.0beta36 but is not noted in the CHANGES. Similarly,
+ it was changed from png_charpp to png_const_bytepp in png_set_iCCP().
+ Ensure that png_rgb_to_gray ignores palette mapped images, if libpng
+ internally happens to call it with one, and fixed a failure to handle
+ palette mapped images correctly. This fixes CVE-2690.
+
+Version 1.5.1beta02 [January 14, 2011]
+ Fixed a bug in handling of interlaced images (bero at arklinux.org).
+ Updated CMakeLists.txt (Clifford Yapp)
+
+Version 1.5.1beta03 [January 14, 2011]
+ Fixed typecasting of some png_debug() statements (Cosmin)
+
+Version 1.5.1beta04 [January 16, 2011]
+ Updated documentation of png_set|get_tRNS() (Thomas Klausner).
+ Mentioned in the documentation that applications must #include "zlib.h"
+ if they need access to anything in zlib.h, and that a number of
+ macros such as png_memset() are no longer accessible by applications.
+ Corrected pngvalid gamma test "sample" function to access all of the color
+ samples of each pixel, instead of sampling the red channel three times.
+ Prefixed variable names index, div, exp, gamma with "png_" to avoid "shadow"
+ warnings, and (mistakenly) changed png_exp() to exp().
+
+Version 1.5.1beta05 [January 16, 2011]
+ Changed variable names png_index, png_div, png_exp, and png_gamma to
+ char_index, divisor, exp_b10, and gamma_val, respectively, and
+ changed exp() back to png_exp().
+
+Version 1.5.1beta06 [January 20, 2011]
+ Prevent png_push_crc_skip() from hanging while reading an unknown chunk
+ or an over-large compressed zTXt chunk with the progressive reader.
+ Eliminated more GCC "shadow" warnings.
+ Revised png_fixed() in png.c to avoid compiler warning about reaching the
+ end without returning anything.
+
+Version 1.5.1beta07 [January 22, 2011]
+ In the manual, describe the png_get_IHDR() arguments in the correct order.
+ Added const_png_structp and const_png_infop types, and used them in
+ prototypes for most png_get_*() functions.
+
+Version 1.5.1beta08 [January 23, 2011]
+ Added png_get_io_chunk_type() and deprecated png_get_io_chunk_name()
+ Added synopses for the IO_STATE functions and other missing synopses
+ to the manual. Removed the synopses from libpngpf.3 because they
+ were out of date and no longer useful. Better information can be
+ obtained by reading the prototypes and comments in pngpriv.h
+ Attempted to fix cpp on Solaris with S. Studio 12 cc, fix build
+ Added a make macro DFNCPP that is a CPP that will accept the tokens in
+ a .dfn file and adds configure stuff to test for such a CPP. ./configure
+ should fail if one is not available.
+ Corrected const_png_ in png.h to png_const_ to avoid polluting the namespace.
+ Added png_get_current_row_number and png_get_current_pass_number for the
+ benefit of the user transform callback.
+ Added png_process_data_pause and png_process_data_skip for the benefit of
+ progressive readers that need to stop data processing or want to optimize
+ skipping of unread data (e.g., if the reader marks a chunk to be skipped.)
+
+Version 1.5.1beta09 [January 24, 2011]
+ Enhanced pngvalid, corrected an error in gray_to_rgb, corrected doc error.
+ pngvalid contains tests of transforms, which tests are currently disabled
+ because they are incompletely tested. gray_to_rgb was failing to expand
+ the bit depth for smaller bit depth images; this seems to be a long
+ standing error and resulted, apparently, in invalid output
+ (CVE-2011-0408, CERT VU#643140). The documentation did not accurately
+ describe what libpng really does when converting RGB to gray.
+
+Version 1.5.1beta10 [January 27, 2010]
+ Fixed incorrect examples of callback prototypes in the manual, that were
+ introduced in libpng-1.0.0.
+ In addition the order of the png_get_uint macros with respect to the
+ relevant function definitions has been reversed. This helps the
+ preprocessing of the symbol files be more robust. Furthermore, the
+ symbol file preprocessing now uses -DPNG_NO_USE_READ_MACROS even when
+ the library may actually be built with PNG_USE_READ_MACROS; this stops
+ the read macros interfering with the symbol file format.
+ Made the manual, synopses, and function prototypes use the function
+ argument names file_gamma, int_file_gamma, and srgb_intent consistently.
+
+Version 1.5.1beta11 [January 28, 2011]
+ Changed PNG_UNUSED from "param=param;" to "{if(param){}}".
+ Corrected local variable type in new API png_process_data_skip()
+ The type was self-evidently incorrect but only causes problems on 64-bit
+ architectures.
+ Added transform tests to pngvalid and simplified the arguments.
+
+Version 1.5.1rc01 [January 29, 2011]
+ No changes.
+
+Version 1.5.1rc02 [January 31, 2011]
+ Added a request in the manual that applications do not use "png_" or
+ "PNG_" to begin any of their own symbols.
+ Changed PNG_UNUSED to "(void)param;" and updated the commentary in pngpriv.h
+
+Version 1.5.1 [February 3, 2011]
+ No changes.
+
+Version 1.5.2beta01 [February 13, 2011]
+ More -Wshadow fixes for older gcc compilers. Older gcc versions apparently
+ check formal parameters names in function declarations (as well as
+ definitions) to see if they match a name in the global namespace.
+ Revised PNG_EXPORTA macro to not use an empty parameter, to accommodate the
+ old VisualC++ preprocessor.
+ Turned on interlace handling in png_read_png().
+ Fixed gcc pendantic warnings.
+ Handle longjmp in Cygwin.
+ Fixed png_get_current_row_number() in the interlaced case.
+ Cleaned up ALPHA flags and transformations.
+ Implemented expansion to 16 bits.
+
+Version 1.5.2beta02 [February 19, 2011]
+ Fixed mistake in the descriptions of user read_transform and write_transform
+ function prototypes in the manual. The row_info struct is png_row_infop.
+ Reverted png_get_current_row_number() to previous (1.5.2beta01) behavior.
+ Corrected png_get_current_row_number documentation
+ Fixed the read/write row callback documentation.
+ This documents the current behavior, where the callback is called after
+ every row with information pertaining to the next row.
+
+Version 1.5.2beta03 [March 3, 2011]
+ Fixed scripts/makefile.vcwin32
+ Updated contrib/pngsuite/README to add the word "modify".
+ Define PNG_ALLOCATED to blank when _MSC_VER<1300.
+
+Version 1.5.2rc01 [March 19, 2011]
+ Define remaining attributes to blank when MSC_VER<1300.
+ ifdef out mask arrays in pngread.c when interlacing is not supported.
+
+Version 1.5.2rc02 [March 22, 2011]
+ Added a hint to try CPP=/bin/cpp if "cpp -E" fails in scripts/pnglibconf.mak
+ and in contrib/pngminim/*/makefile, eg., on SunOS 5.10, and removed "strip"
+ from the makefiles.
+ Fixed a bug (present since libpng-1.0.7) that makes png_handle_sPLT() fail
+ to compile when PNG_NO_POINTER_INDEXING is defined (Chubanov Kirill)
+
+Version 1.5.2rc03 [March 24, 2011]
+ Don't include standard header files in png.h while building the symbol table,
+ to avoid cpp failure on SunOS (introduced PNG_BUILDING_SYMBOL_TABLE macro).
+
+Version 1.5.2 [March 31, 2011]
+ No changes.
+
+Version 1.5.3beta01 [April 1, 2011]
+ Re-initialize the zlib compressor before compressing non-IDAT chunks.
+ Added API functions (png_set_text_compression_level() and four others) to
+ set parameters for zlib compression of non-IDAT chunks.
+
+Version 1.5.3beta02 [April 3, 2011]
+ Updated scripts/symbols.def with new API functions.
+ Only compile the new zlib re-initializing code when text or iCCP is
+ supported, using PNG_WRITE_COMPRESSED_TEXT_SUPPORTED macro.
+ Improved the optimization of the zlib CMF byte (see libpng-1.2.6beta03).
+ Optimize the zlib CMF byte in non-IDAT compressed chunks
+
+Version 1.5.3beta03 [April 16, 2011]
+ Fixed gcc -ansi -pedantic compile. A strict ANSI system does not have
+ snprintf, and the "__STRICT_ANSI__" detects that condition more reliably
+ than __STDC__ (John Bowler).
+ Removed the PNG_PTR_NORETURN attribute because it too dangerous. It tells
+ the compiler that a user supplied callback (the error handler) does not
+ return, yet there is no guarantee in practice that the application code
+ will correctly implement the error handler because the compiler only
+ issues a warning if there is a mistake (John Bowler).
+ Removed the no-longer-used PNG_DEPSTRUCT macro.
+ Updated the zlib version to 1.2.5 in the VStudio project.
+ Fixed 64-bit builds where png_uint_32 is smaller than png_size_t in
+ pngwutil.c (John Bowler).
+ Fixed bug with stripping the filler or alpha channel when writing, that
+ was introduced in libpng-1.5.2beta01 (bug report by Andrew Church).
+
+Version 1.5.3beta04 [April 27, 2011]
+ Updated pngtest.png with the new zlib CMF optimization.
+ Cleaned up conditional compilation code and of background/gamma handling
+ Internal changes only except a new option to avoid compiling the
+ png_build_grayscale_palette API (which is not used at all internally.)
+ The main change is to move the transform tests (READ_TRANSFORMS,
+ WRITE_TRANSFORMS) up one level to the caller of the APIs. This avoids
+ calls to spurious functions if all transforms are disabled and slightly
+ simplifies those functions. Pngvalid modified to handle this.
+ A minor change is to stop the strip_16 and expand_16 interfaces from
+ disabling each other; this allows the future alpha premultiplication
+ code to use 16-bit intermediate values while still producing 8-bit output.
+ png_do_background and png_do_gamma have been simplified to take a single
+ pointer to the png_struct rather than pointers to every item required
+ from the png_struct. This makes no practical difference to the internal
+ code.
+ A serious bug in the pngvalid internal routine 'standard_display_init' has
+ been fixed - this failed to initialize the red channel and accidentally
+ initialized the alpha channel twice.
+ Changed png_struct jmp_buf member name from png_jmpbuf to tmp_jmpbuf to
+ avoid a possible clash with the png_jmpbuf macro on some platforms.
+
+Version 1.5.3beta05 [May 6, 2011]
+ Added the "_POSIX_SOURCE" feature test macro to ensure libpng sees the
+ correct API. _POSIX_SOURCE is defined in pngpriv.h, pngtest.c and
+ pngvalid.c to ensure that POSIX conformant systems disable non-POSIX APIs.
+ Removed png_snprintf and added formatted warning messages. This change adds
+ internal APIs to allow png_warning messages to have parameters without
+ requiring the host OS to implement snprintf. As a side effect the
+ dependency of the tIME-supporting RFC1132 code on stdio is removed and
+ PNG_NO_WARNINGS does actually work now.
+ Pass "" instead of '\0' to png_default_error() in png_err(). This mistake
+ was introduced in libpng-1.2.20beta01. This fixes CVE-2011-2691.
+ Added PNG_WRITE_OPTIMIZE_CMF_SUPPORTED macro to make the zlib "CMF" byte
+ optimization configureable.
+ IDAT compression failed if preceded by a compressed text chunk (bug
+ introduced in libpng-1.5.3beta01-02). This was because the attempt to
+ reset the zlib stream in png_write_IDAT happened after the first IDAT
+ chunk had been deflated - much too late. In this change internal
+ functions were added to claim/release the z_stream and, hopefully, make
+ the code more robust. Also deflateEnd checking is added - previously
+ libpng would ignore an error at the end of the stream.
+
+Version 1.5.3beta06 [May 8, 2011]
+ Removed the -D_ALL_SOURCE from definitions for AIX in CMakeLists.txt
+ Implemented premultiplied alpha support: png_set_alpha_mode API
+
+Version 1.5.3beta07 [May 11, 2011]
+ Added expand_16 support to the high level interface.
+ Added named value and 'flag' gamma support to png_set_gamma. Made a minor
+ change from the previous (unreleased) ABI/API to hide the exact value used
+ for Macs - it's not a good idea to embed this in the ABI!
+ Moved macro definitions for PNG_HAVE_IHDR, PNG_HAVE_PLTE, and PNG_AFTER_IDAT
+ from pngpriv.h to png.h because they must be visible to applications
+ that call png_set_unknown_chunks().
+ Check for up->location !PNG_AFTER_IDAT when writing unknown chunks
+ before IDAT.
+
+Version 1.5.3beta08 [May 16, 2011]
+ Improved "pngvalid --speed" to exclude more of pngvalid from the time.
+ Documented png_set_alpha_mode(), other changes in libpng.3/libpng-manual.txt
+ The cHRM chunk now sets the defaults for png_set_rgb_to_gray() (when negative
+ parameters are supplied by the caller), while in the absence of cHRM
+ sRGB/Rec 709 values are still used. This introduced a divide-by-zero
+ bug in png_handle_cHRM().
+ The bKGD chunk no longer overwrites the background value set by
+ png_set_background(), allowing the latter to be used before the file
+ header is read. It never performed any useful function to override
+ the default anyway.
+ Added memory overwrite and palette image checks to pngvalid.c
+ Previously palette image code was poorly checked. Since the transformation
+ code has a special palette path in most cases this was a severe weakness.
+ Minor cleanup and some extra checking in pngrutil.c and pngrtran.c. When
+ expanding an indexed image, always expand to RGBA if transparency is
+ present.
+
+Version 1.5.3beta09 [May 17, 2011]
+ Reversed earlier 1.5.3 change of transformation order; move png_expand_16
+ back where it was. The change doesn't work because it requires 16-bit
+ gamma tables when the code only generates 8-bit ones. This fails
+ silently; the libpng code just doesn't do any gamma correction. Moving
+ the tests back leaves the old, inaccurate, 8-bit gamma calculations, but
+ these are clearly better than none!
+
+Version 1.5.3beta10 [May 20, 2011]
+
+ png_set_background() and png_expand_16() did not work together correctly.
+ This problem is present in 1.5.2; if png_set_background is called with
+ need_expand false and the matching 16 bit color libpng erroneously just
+ treats it as an 8-bit color because of where png_do_expand_16 is in the
+ transform list. This simple fix reduces the supplied colour to 8-bits,
+ so it gets smashed, but this is better than the current behavior.
+ Added tests for expand16, more fixes for palette image tests to pngvalid.
+ Corrects the code for palette image tests and disables attempts to
+ validate palette colors.
+
+Version 1.5.3rc01 [June 3, 2011]
+ No changes.
+
+Version 1.5.3rc02 [June 8, 2011]
+ Fixed uninitialized memory read in png_format_buffer() (Bug report by
+ Frank Busse, CVE-2011-2501, related to CVE-2004-0421).
+
+Version 1.5.3beta11 [June 11, 2011]
+ Fixed png_handle_sCAL which is broken in 1.5. This fixes CVE 2011-2692.
+ Added sCAL to pngtest.png
+ Revised documentation about png_set_user_limits() to say that it also affects
+ png writing.
+ Revised handling of png_set_user_limits() so that it can increase the
+ limit beyond the PNG_USER_WIDTH|HEIGHT_MAX; previously it could only
+ reduce it.
+ Make the 16-to-8 scaling accurate. Dividing by 256 with no rounding is
+ wrong (high by one) 25% of the time. Dividing by 257 with rounding is
+ wrong in 128 out of 65536 cases. Getting the right answer all the time
+ without division is easy.
+ Added "_SUPPORTED" to the PNG_WRITE_CUSTOMIZE_ZTXT_COMPRESSION macro.
+ Added projects/owatcom, an IDE project for OpenWatcom to replace
+ scripts/makefile.watcom. This project works with OpenWatcom 1.9. The
+ IDE autogenerates appropriate makefiles (libpng.mk) for batch processing.
+ The project is configurable, unlike the Visual Studio project, so long
+ as the developer has an awk.
+ Changed png_set_gAMA to limit the gamma value range so that the inverse
+ of the stored value cannot overflow the fixed point representation,
+ and changed other things OpenWatcom warns about.
+ Revised pngvalid.c to test PNG_ALPHA_MODE_SUPPORTED correctly. This allows
+ pngvalid to build when ALPHA_MODE is not supported, which is required if
+ it is to build on libpng 1.4.
+ Removed string/memory macros that are no longer used and are not
+ necessarily fully supportable, particularly png_strncpy and png_snprintf.
+ Added log option to pngvalid.c and attempted to improve gamma messages.
+
+Version 1.5.3 [omitted]
+ People found the presence of a beta release following an rc release
+ to be confusing; therefore we bump the version to libpng-1.5.4beta01
+ and there will be no libpng-1.5.3 release.
+
+Version 1.5.4beta01 [June 14, 2011]
+ Made it possible to undefine PNG_READ_16_TO_8_ACCURATE_SCALE_SUPPORTED
+ to get the same (inaccurate) output as libpng-1.5.2 and earlier.
+ Moved definitions of PNG_HAVE_IHDR, PNG_AFTER_IDAT, and PNG_HAVE_PLTE
+ outside of an unknown-chunk block in png.h because they are also
+ needed for other uses.
+
+Version 1.5.4beta02 [June 14, 2011]
+ Fixed and clarified LEGACY 16-to-8 scaling code.
+ Added png_set_chop_16() API, to match inaccurate results from previous
+ libpng versions.
+ Removed the ACCURATE and LEGACY options (they are no longer useable)
+ Use the old scaling method for background if png_set_chop_16() was
+ called.
+ Made png_set_chop_16() API removeable by disabling PNG_CHOP_16_TO_8_SUPPORTED
+
+Version 1.5.4beta03 [June 15, 2011]
+ Fixed a problem in png_do_expand_palette() exposed by optimization in
+ 1.5.3beta06
+ Also removed a spurious and confusing "trans" member ("trans") from png_info.
+ The palette expand optimization prevented expansion to an intermediate RGBA
+ form if tRNS was present but alpha was marked to be stripped; this exposed
+ a check for tRNS in png_do_expand_palette() which is inconsistent with the
+ code elsewhere in libpng.
+ Correction to the expand_16 code; removed extra instance of
+ png_set_scale_16_to_8 from pngpriv.h
+
+Version 1.5.4beta04 [June 16, 2011]
+ Added a missing "#ifdef PNG_READ_BACKGROUND_SUPPORTED/#endif" in pngrtran.c
+ Added PNG_TRANSFORM_CHOP_16 to the high-level read transforms.
+ Made PNG_READ_16_TO_8_ACCURATE_SCALE configurable again. If this is
+ not enabled, png_set_strip_16() and png_do_scale_16_to_8() aren't built.
+ Revised contrib/visupng, gregbook, and pngminim to demonstrate chop_16_to_8
+
+Version 1.5.4beta05 [June 16, 2011]
+ Renamed png_set_strip_16() to png_set_scale_16() and renamed
+ png_set_chop_16() to png_set_strip(16) in an attempt to minimize the
+ behavior changes between libpng14 and libpng15.
+
+Version 1.5.4beta06 [June 18, 2011]
+ Fixed new bug that was causing both strip_16 and scale_16 to be applied.
+
+Version 1.5.4beta07 [June 19, 2011]
+ Fixed pngvalid, simplified macros, added checking for 0 in sCAL.
+ The ACCURATE scale macro is no longer defined in 1.5 - call the
+ png_scale_16_to_8 API. Made sure that PNG_READ_16_TO_8 is still defined
+ if the png_strip_16_to_8 API is present. png_check_fp_number now
+ maintains some state so that positive, negative and zero values are
+ identified. sCAL uses these to be strictly spec conformant.
+
+Version 1.5.4beta08 [June 23, 2011]
+ Fixed pngvalid if ACCURATE_SCALE is defined.
+ Updated scripts/pnglibconf.h.prebuilt.
+
+Version 1.5.4rc01 [June 30, 2011]
+ Define PNG_ALLOCATED to "restrict" only if MSC_VER >= 1400.
+
+Version 1.5.4 [July 7, 2011]
+ No changes.
+
+Version 1.5.5beta01 [July 13, 2011]
+ Fixed some typos and made other minor changes in the manual.
+ Updated contrib/pngminus/makefile.std (Samuli Souminen)
+
+Version 1.5.5beta02 [July 14, 2011]
+ Revised Makefile.am and Makefile.in to look in the right directory for
+ pnglibconf.h.prebuilt
+
+Version 1.5.5beta03 [July 27, 2011]
+ 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.
+
+Version 1.5.5beta04 [July 29, 2011]
+ Revised CMakeLists.txt (Clifford Yapp)
+ Updated commentary about the png_rgb_to_gray() default coefficients
+ in the manual and in pngrtran.c
+
+Version 1.5.5beta05 [August 17, 2011]
+ 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
+ configurations.)
+ Added new types and internal functions for CIE RGB end point handling to
+ pngpriv.h (functions yet to be implemented).
+
+Version 1.5.5beta06 [August 26, 2011]
+ Ensure the CMAKE_LIBRARY_OUTPUT_DIRECTORY is set in CMakeLists.txt
+ (Clifford Yap)
+ 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
+ rgb_to_gray transform.
+ 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.
+
+Version 1.5.5beta07 [September 7, 2011]
+ 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
+ png_XYZ_from_xy_checked().
+
+Version 1.5.5beta08 [September 10, 2011]
+ 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 which the
+ compiler correctly flags.
+ Relocated new HAVE_SOLARIS_LD definition in configure.ac
+ 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.
+
+Version 1.5.5rc01 [September 15, 2011]
+ Removed "L" suffixes in pngpriv.h
+
+Version 1.5.5 [September 22, 2011]
+ No changes.
+
+Version 1.5.6beta01 [September 22, 2011]
+ 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_destroy_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.
+
+Version 1.5.6beta02 [September 26, 2011]
+ Added a note in the manual the png_read_update_info() must be called only
+ once with a particular info_ptr.
+ Fixed a typo in the definition of the new PNG_STRING_FROM_CHUNK(s,c) macro.
+
+Version 1.5.6beta03 [September 28, 2011]
+ 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.
+
+Version 1.5.6beta04 [October 5, 2011]
+ Fixed typo in Makefile.in and Makefile.am ("-M Wl" should be "-M -Wl")."
+
+Version 1.5.6beta05 [October 12, 2011]
+ 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.
+ Fixed bug in png_write_chunk_header() debug print, introduced in 1.5.6beta01.
+
+Version 1.5.6beta06 [October 17, 2011]
+ 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.
+
+Version 1.5.6beta07 [October 21, 2011]
+ Made png_ptr->prev_row an aligned pointer into png_ptr->big_prev_row
+ (Mans Rullgard).
+
+Version 1.5.6rc01 [October 26, 2011]
+ Changed misleading "Missing PLTE before cHRM" warning to "Out of place cHRM"
+
+Version 1.5.6rc02 [October 27, 2011]
+ Added LSR() macro to defend against buggy compilers that evaluate non-taken
+ code branches and complain about out-of-range shifts.
+
+Version 1.5.6rc03 [October 28, 2011]
+ Renamed the LSR() macro to PNG_LSR() and added PNG_LSL() macro.
+ Fixed compiler warnings with Intel and MSYS compilers. The logical shift
+ fix for Microsoft Visual C is required by other compilers, so this
+ enables that fix for all compilers when using compile-time constants.
+ Under MSYS 'byte' is a name declared in a system header file, so we
+ changed the name of a local variable to avoid the warnings that result.
+ Added #define PNG_ALIGN_TYPE PNG_ALIGN_NONE to contrib/pngminim/*/pngusr.h
+
+Version 1.5.6 [November 3, 2011]
+ No changes.
+
+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.
+
+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
+#endif