[devel] Imported from libpng-1.5.2rc01.tar

[devel] Define remaining attributes to blank when MSC_VER<1300.
[devel] Bump to version libpng-1.5.2beta04
2025-07-10 18:04:09 +02:00 · 2011-03-18 22:03:48 -05:00 · 2011-03-06 16:49:10 -06:00 · 2011-03-03 06:41:16 -06:00 · 2011-03-03 06:37:45 -06:00 · 2011-03-03 06:24:32 -06:00
92 changed files with 12110 additions and 6255 deletions
--- a/466
+++ b/466
@@ -1,5 +1,5 @@

-Libpng 1.5.0beta55 - November 21, 2010
+Libpng 1.5.2rc01 - March 19, 2011

 This is not intended to be a public release.  It will be replaced
 within a few weeks by a public version or by another test version.
@@ -9,448 +9,52 @@ Files available for download:
 Source files with LF line endings (for Unix/Linux) and with a
 "configure" script

-   1.5.0beta55.tar.xz (LZMA-compressed, recommended)
-   1.5.0beta55.tar.gz
-   1.5.0beta55.tar.bz2
+   1.5.2rc01.tar.xz (LZMA-compressed, recommended)
+   1.5.2rc01.tar.gz
+   1.5.2rc01.tar.bz2

 Source files with CRLF line endings (for Windows), without the
 "configure" script

-   lp150b55.zip
-   lp150b55.7z
+   lp152r01.7z  (LZMA-compressed, recommended)
+   lp152r01.zip

 Other information:

-   1.5.0beta55-README.txt
-   1.5.0beta55-LICENSE.txt
+   1.5.2rc01-README.txt
+   1.5.2rc01-LICENSE.txt

-Changes since the last public release (1.4.1):
+Changes since the last public release (1.5.1):

-version 1.5.0beta01 [February 7, 2010]
-  Moved declaration of png_struct into private pngstruct.h and png_info
-    into pnginfo.h
+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 1.5.0beta02 [February 7, 2010]
-  Reverted to original png_push_save_buffer() code.
+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 1.5.0beta03 [February 8, 2010]
-  Return allocated "old_buffer" in png_push_save_buffer() before
-    calling png_error().
-  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]
-  Made 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]
-  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.
-
-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 [November 21, 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 19, 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, 2010]
-  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.
-
-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 1.5.2beta03 [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.

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 (subscription required; visit
--- a/182
+++ b/182
@@ -3089,6 +3089,188 @@ Version 1.5.0beta55 [November 21, 2010]
    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.
+  Fixed a failure to handle palette mapped images correctly.
+
+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.  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.

 Send comments/corrections/commendations to png-mng-implement at lists.sf.net
 (subscription required; visit
--- a/CMakeLists.txt
+++ b/CMakeLists.txt
@@ -25,7 +25,7 @@ endif()
 project(libpng C)
 enable_testing()

-# Copyright (C) 2007-2010 Glenn Randers-Pehrson
+# Copyright (C) 2007-2011 Glenn Randers-Pehrson

 # This code is released under the libpng license.
 # For conditions of distribution and use, see the disclaimer
@@ -33,7 +33,7 @@ enable_testing()

 set(PNGLIB_MAJOR 1)
 set(PNGLIB_MINOR 5)
-set(PNGLIB_RELEASE 0)
+set(PNGLIB_RELEASE 2)
 set(PNGLIB_NAME libpng${PNGLIB_MAJOR}${PNGLIB_MINOR})
 set(PNGLIB_VERSION ${PNGLIB_MAJOR}.${PNGLIB_MINOR}.${PNGLIB_RELEASE})

@@ -240,28 +240,31 @@ endmacro()
 # CREATE PKGCONFIG FILES
 # we use the same files like ./configure, so we have to set its vars
 if(NOT DEFINED CMAKE_INSTALL_LIBDIR)
-  set(CMAKE_INSTALL_LIBDIR ${CMAKE_INSTALL_PREFIX}/lib)
+  set(CMAKE_INSTALL_LIBDIR lib)
 endif(NOT DEFINED CMAKE_INSTALL_LIBDIR)
 set(prefix      ${CMAKE_INSTALL_PREFIX})
 set(exec_prefix ${CMAKE_INSTALL_PREFIX})
-set(libdir      ${CMAKE_INSTALL_LIBDIR})
+set(libdir      ${CMAKE_INSTALL_PREFIX}/${CMAKE_INSTALL_LIBDIR})
 set(includedir  ${CMAKE_INSTALL_PREFIX}/include)
 set(LIBS        "-lz -lm")
 configure_file(${CMAKE_CURRENT_SOURCE_DIR}/libpng.pc.in
  ${CMAKE_CURRENT_BINARY_DIR}/${PNGLIB_NAME}.pc @ONLY)
-_png_generate_symlink_code(PNG_PC_INSTALL_CODE ${PNGLIB_NAME}.pc libpng.pc)
+_png_generate_symlink_code(PNG_PC_INSTALL_CODE
+  ${CMAKE_CURRENT_BINARY_DIR}/${PNGLIB_NAME}.pc
+  ${CMAKE_CURRENT_BINARY_DIR}/libpng.pc)
 install(CODE ${PNG_PC_INSTALL_CODE})

 configure_file(${CMAKE_CURRENT_SOURCE_DIR}/libpng-config.in
  ${CMAKE_CURRENT_BINARY_DIR}/${PNGLIB_NAME}-config @ONLY)
-_png_generate_symlink_code(PNG_CONFIG_INSTALL_CODE ${PNGLIB_NAME}-config
-  libpng-config)
+_png_generate_symlink_code(PNG_CONFIG_INSTALL_CODE
+  ${CMAKE_CURRENT_BINARY_DIR}/${PNGLIB_NAME}-config
+  ${CMAKE_CURRENT_BINARY_DIR}/libpng-config)
 install(CODE ${PNG_CONFIG_INSTALL_CODE})

 # SET UP LINKS
 if(PNG_SHARED)
  set_target_properties(${PNG_LIB_NAME} PROPERTIES
-#   VERSION 15.${PNGLIB_RELEASE}.1.5.0beta55
+#   VERSION 15.${PNGLIB_RELEASE}.1.5.2rc01
    VERSION 15.${PNGLIB_RELEASE}.0
    SOVERSION 15
    CLEAN_DIRECT_OUTPUT 1)
@@ -295,7 +298,7 @@ if(NOT SKIP_INSTALL_LIBRARIES AND NOT SKIP_INSTALL_ALL )
        LIBRARY DESTINATION ${CMAKE_INSTALL_LIBDIR}
        ARCHIVE DESTINATION ${CMAKE_INSTALL_LIBDIR})

-    # Create a symlink for libpng.dll.a => libpng14.dll.a on Cygwin
+    # Create a symlink for libpng.dll.a => libpng15.dll.a on Cygwin
    if(CYGWIN)
      _png_generate_symlink_code(PNG_SHARED_IMPLIB_INSTALL_CODE
        ${PNGLIB_NAME}${CMAKE_IMPORT_LIBRARY_SUFFIX}
@@ -307,13 +310,23 @@ if(NOT SKIP_INSTALL_LIBRARIES AND NOT SKIP_INSTALL_ALL )
    endif()

    if(NOT WIN32)
-      _png_generate_symlink_code(PNG_SHARED_INSTALL_CODE
-            ${PNGLIB_NAME}${CMAKE_SHARED_LIBRARY_SUFFIX}
-            libpng${CMAKE_SHARED_LIBRARY_SUFFIX})
-      install(CODE ${PNG_SHARED_INSTALL_CODE})
-      install(FILES
-        ${CMAKE_CURRENT_BINARY_DIR}/libpng${CMAKE_SHARED_LIBRARY_SUFFIX}
-        DESTINATION ${CMAKE_INSTALL_LIBDIR})
+      IF(CMAKE_LIBRARY_OUTPUT_DIRECTORY)
+        _png_generate_symlink_code(PNG_SHARED_INSTALL_CODE
+ ${CMAKE_LIBRARY_OUTPUT_DIRECTORY}/${PNGLIB_NAME}${CMAKE_SHARED_LIBRARY_SUFFIX}
+ ${CMAKE_LIBRARY_OUTPUT_DIRECTORY}/libpng${CMAKE_SHARED_LIBRARY_SUFFIX})
+                install(CODE ${PNG_SHARED_INSTALL_CODE})
+                install(FILES
+ ${CMAKE_LIBRARY_OUTPUT_DIRECTORY}/libpng${CMAKE_SHARED_LIBRARY_SUFFIX}
+                DESTINATION ${CMAKE_INSTALL_LIBDIR})
+      ELSE(CMAKE_LIBRARY_OUTPUT_DIRECTORY)
+        _png_generate_symlink_code(PNG_SHARED_INSTALL_CODE
+           ${PNGLIB_NAME}${CMAKE_SHARED_LIBRARY_SUFFIX}
+           libpng${CMAKE_SHARED_LIBRARY_SUFFIX})
+        install(CODE ${PNG_SHARED_INSTALL_CODE})
+        install(FILES
+           ${CMAKE_CURRENT_BINARY_DIR}/libpng${CMAKE_SHARED_LIBRARY_SUFFIX}
+                DESTINATION ${CMAKE_INSTALL_LIBDIR})
+      ENDIF(CMAKE_LIBRARY_OUTPUT_DIRECTORY)
    endif()
  endif()

@@ -323,13 +336,23 @@ if(NOT SKIP_INSTALL_LIBRARIES AND NOT SKIP_INSTALL_ALL )
            LIBRARY DESTINATION ${CMAKE_INSTALL_LIBDIR}
            ARCHIVE DESTINATION ${CMAKE_INSTALL_LIBDIR})
    if(NOT WIN32 OR CYGWIN)
-      _png_generate_symlink_code(PNG_STATIC_INSTALL_CODE
-            ${PNGLIB_NAME}${CMAKE_STATIC_LIBRARY_SUFFIX}
-            libpng${CMAKE_STATIC_LIBRARY_SUFFIX})
-      install(CODE ${PNG_STATIC_INSTALL_CODE})
-      install(FILES
-        ${CMAKE_CURRENT_BINARY_DIR}/libpng${CMAKE_STATIC_LIBRARY_SUFFIX}
-        DESTINATION ${CMAKE_INSTALL_LIBDIR})
+      IF(CMAKE_ARCHIVE_OUTPUT_DIRECTORY)
+         _png_generate_symlink_code(PNG_STATIC_INSTALL_CODE
+${CMAKE_ARCHIVE_OUTPUT_DIRECTORY}/${PNGLIB_NAME}${CMAKE_STATIC_LIBRARY_SUFFIX}
+        ${CMAKE_ARCHIVE_OUTPUT_DIRECTORY}/libpng${CMAKE_STATIC_LIBRARY_SUFFIX})
+        install(CODE ${PNG_STATIC_INSTALL_CODE})
+        install(FILES
+          ${CMAKE_ARCHIVE_OUTPUT_DIRECTORY}/libpng${CMAKE_STATIC_LIBRARY_SUFFIX}
+             DESTINATION ${CMAKE_INSTALL_LIBDIR})
+      ELSE(CMAKE_ARCHIVE_OUTPUT_DIRECTORY)
+        _png_generate_symlink_code(PNG_STATIC_INSTALL_CODE
+           ${PNGLIB_NAME}${CMAKE_STATIC_LIBRARY_SUFFIX}
+           libpng${CMAKE_STATIC_LIBRARY_SUFFIX})
+        install(CODE ${PNG_STATIC_INSTALL_CODE})
+        install(FILES
+          ${CMAKE_CURRENT_BINARY_DIR}/libpng${CMAKE_STATIC_LIBRARY_SUFFIX}
+                     DESTINATION ${CMAKE_INSTALL_LIBDIR})
+      ENDIF(CMAKE_ARCHIVE_OUTPUT_DIRECTORY)
    endif()
  endif()
 endif()
@@ -367,7 +390,7 @@ if(PNG_EXPORT_RULE AND NOT SKIP_INSTALL_EXPORT AND NOT SKIP_INSTALL_ALL )
  install(EXPORT libpng DESTINATION lib/libpng FILE lib${PNG_LIB_NAME}.cmake)
 endif()

-# what's with libpng-manual.txt and all the extra files?
+# what's with libpng-$VER%.txt and all the extra files?


 # UNINSTALL
--- a/6
+++ b/6
@@ -10,8 +10,8 @@ this sentence.

 This code is released under the libpng license.

-libpng versions 1.2.6, August 15, 2004, through 1.5.0beta55, November 21, 2010, are
-Copyright (c) 2004, 2006-2010 Glenn Randers-Pehrson, and are
+libpng versions 1.2.6, August 15, 2004, through 1.5.2rc01, March 19, 2011, are
+Copyright (c) 2004, 2006-2011 Glenn Randers-Pehrson, and are
 distributed according to the same disclaimer and license as libpng-1.2.5
 with the following individual added to the list of Contributing Authors

@@ -108,4 +108,4 @@ certification mark of the Open Source Initiative.

 Glenn Randers-Pehrson
 glennrp at users.sourceforge.net
-November 21, 2010
+March 19, 2011
--- a/Makefile.am
+++ b/Makefile.am
@@ -17,7 +17,7 @@ pngtest_SOURCES = pngtest.c
 pngtest_LDADD = libpng@PNGLIB_MAJOR@@PNGLIB_MINOR@.la
 pngvalid_SOURCES = pngvalid.c
 pngvalid_LDADD = libpng@PNGLIB_MAJOR@@PNGLIB_MINOR@.la
-TESTS = test-pngtest.sh pngvalid
+TESTS = test-pngtest.sh test-pngvalid-simple.sh test-pngvalid-full.sh
 TESTS_ENVIRONMENT= srcdir=$(srcdir) 

 # man pages
@@ -75,12 +75,19 @@ SCRIPT_CLEANFILES=scripts/*.out scripts/*.chk scripts/pnglibconf.dfn

 CLEANFILES= dfn.c dfn?.out pngout.png libpng@PNGLIB_MAJOR@@PNGLIB_MINOR@.pc \
 	libpng@PNGLIB_MAJOR@@PNGLIB_MINOR@-config libpng.vers libpng.sym \
-	pngwin.def check.new pnglibconf.* symbols.new \
+	check.new pnglibconf.* symbols.new pngtest-log.txt \
 	$(SCRIPT_CLEANFILES)

 MAINTAINERCLEANFILES = Makefile.in aclocal.m4 config.guess config.h.in \
 config.sub configure depcomp install-sh ltmain.sh missing

+# DFNCPP is normally just CPP - the C preprocessor - but on Solaris and maybe
+# other operating systems (NeXT?) the C preprocessor selected by configure
+# checks input tokens for validity - effectively it performs part of the ANSI-C
+# parsing - and therefore fails with the .df files.  configure.ac has special
+# checks for this and sets DFNCPP appropriately.
+DFNCPP = @DFNCPP@
+
 SUFFIXES = .chk .dfn .out

 $(PNGLIB_BASENAME).pc: libpng.pc
@@ -90,7 +97,7 @@ $(PNGLIB_BASENAME)-config: libpng-config
 	cp libpng-config $@

 scripts/sym.out scripts/vers.out: png.h pngconf.h pnglibconf.h
-scripts/symbols.out scripts/pngwin.out: png.h pngconf.h scripts/pnglibconf.h.prebuilt
+scripts/symbols.out: png.h pngconf.h scripts/pnglibconf.h.prebuilt

 libpng.sym: scripts/sym.out
 	rm -f $@
@@ -98,9 +105,6 @@ libpng.sym: scripts/sym.out
 libpng.vers: scripts/vers.out
 	rm -f $@
 	cp $? $@
-pngwin.def: scripts/pngwin.out
-	rm -f $@
-	cp $? $@
 pnglibconf.h: pnglibconf.out
 	rm -f $@
 	cp $? $@
@@ -114,15 +118,19 @@ scripts/pnglibconf.h.prebuilt:
 # 'make test' is the first thing the user does.)
 pngvalid.o pngtest.o: pnglibconf.h

+# We must use -DPNG_NO_USE_READ_MACROS here even when the library may actually
+# be built with PNG_USE_READ_MACROS; this stops the read macros interfering
+# with the symbol file format.
 SYMBOL_CFLAGS = -DPNGLIB_LIBNAME='PNG@PNGLIB_MAJOR@@PNGLIB_MINOR@_0'\
 		-DPNGLIB_VERSION='@PNGLIB_VERSION@'\
-		-DSYMBOL_PREFIX='$(SYMBOL_PREFIX)'
+		-DSYMBOL_PREFIX='$(SYMBOL_PREFIX)'\
+		-DPNG_NO_USE_READ_MACROS

 .dfn.out:
 	rm -f $@ dfn.c dfn?.out
 	test -d scripts || mkdir scripts
 	echo '#include "$<"' >dfn.c
-	$(CPP) $(DEFS) $(DEFAULT_INCLUDES) $(INCLUDES) @LIBPNG_DEFINES@\
+	$(DFNCPP) $(DEFS) $(DEFAULT_INCLUDES) $(INCLUDES) @LIBPNG_DEFINES@\
 	    $(CPPFLAGS) $(SYMBOL_CFLAGS) dfn.c > dfn1.out
 	$(SED) -n -e 's|^.*PNG_DEFN_MAGIC-\(.*\)-PNG_DEFN_END.*$$|\1|p'\
 	    dfn1.out >dfn2.out
@@ -140,7 +148,6 @@ pnglibconf.dfn: scripts/pnglibconf.dfa scripts/options.awk
 	mv dfn2.out $@

 # Symbol checks (.def and .out files should match)
-scripts/pngwin.chk: scripts/checksym.awk scripts/pngwin.def scripts/pngwin.out
 scripts/symbols.chk: scripts/checksym.awk scripts/symbols.def scripts/symbols.out
 .out.chk:
 	rm -f $@ symbols.new
@@ -155,7 +162,7 @@ scripts/pnglibconf.dfn: scripts/pnglibconf.dfa scripts/options.awk
 	test -z "$(CPPFLAGS)" 
 	echo "com @PNGLIB_VERSION@ STANDARD API DEFINITION" |\
 	$(AWK) -f ${srcdir}/scripts/options.awk out=dfn1.out\
-	    logunsupported=1 - ${srcdir}/scripts/pnglibconf.dfa 1>&2
+	    logunsupported=2 - ${srcdir}/scripts/pnglibconf.dfa 1>&2
 	$(AWK) -f ${srcdir}/scripts/options.awk out=dfn2.out dfn1.out 1>&2
 	rm dfn1.out
 	mv dfn2.out $@
@@ -166,7 +173,7 @@ $(libpng@PNGLIB_MAJOR@@PNGLIB_MINOR@_la_OBJECTS): png.h pngconf.h \
 test: check-am

 # Extra checks
-check: scripts/symbols.chk scripts/pngwin.chk
+check: scripts/symbols.chk

 # Don't distribute the generated script files
 dist-hook:
--- a/Makefile.in
+++ b/Makefile.in
@@ -41,7 +41,6 @@ POST_UNINSTALL = :
 build_triplet = @build@
 host_triplet = @host@
 check_PROGRAMS = pngtest$(EXEEXT) pngvalid$(EXEEXT)
-TESTS = test-pngtest.sh pngvalid$(EXEEXT)
@HAVE_LD_VERSION_SCRIPT_TRUE@am__append_1 = -Wl,--version-script=libpng.vers
@HAVE_LD_VERSION_SCRIPT_FALSE@am__append_2 = -export-symbols libpng.sym
 subdir = .
@@ -146,21 +145,8 @@ DATA = $(pkgconfig_DATA)
 HEADERS = $(nodist_pkginclude_HEADERS) $(pkginclude_HEADERS)
 ETAGS = etags
 CTAGS = ctags
-# If stdout is a non-dumb tty, use colors.  If test -t is not supported,
-# then this fails; a conservative approach.  Of course do not redirect
-# stdout here, just stderr.
 am__tty_colors = \
-red=; grn=; lgn=; blu=; std=; \
-test "X$(AM_COLOR_TESTS)" != Xno \
-&& test "X$$TERM" != Xdumb \
-&& { test "X$(AM_COLOR_TESTS)" = Xalways || test -t 1 2>/dev/null; } \
-&& { \
-  red='[0;31m'; \
-  grn='[0;32m'; \
-  lgn='[1;32m'; \
-  blu='[1;34m'; \
-  std='[m'; \
-}
+red=; grn=; lgn=; blu=; std=
 DISTFILES = $(DIST_COMMON) $(DIST_SOURCES) $(TEXINFOS) $(EXTRA_DIST)
 distdir = $(PACKAGE)-$(VERSION)
 top_distdir = $(distdir)
@@ -191,6 +177,13 @@ CPPFLAGS = @CPPFLAGS@
 CYGPATH_W = @CYGPATH_W@
 DEFS = @DEFS@
 DEPDIR = @DEPDIR@
+
+# DFNCPP is normally just CPP - the C preprocessor - but on Solaris and maybe
+# other operating systems (NeXT?) the C preprocessor selected by configure
+# checks input tokens for validity - effectively it performs part of the ANSI-C
+# parsing - and therefore fails with the .df files.  configure.ac has special
+# checks for this and sets DFNCPP appropriately.
+DFNCPP = @DFNCPP@
 DLLTOOL = @DLLTOOL@
 DSYMUTIL = @DSYMUTIL@
 DUMPBIN = @DUMPBIN@
@@ -217,6 +210,7 @@ LN_S = @LN_S@
 LTLIBOBJS = @LTLIBOBJS@
 MAINT = @MAINT@
 MAKEINFO = @MAKEINFO@
+MANIFEST_TOOL = @MANIFEST_TOOL@
 MKDIR_P = @MKDIR_P@
 NM = @NM@
 NMEDIT = @NMEDIT@
@@ -248,6 +242,7 @@ abs_builddir = @abs_builddir@
 abs_srcdir = @abs_srcdir@
 abs_top_builddir = @abs_top_builddir@
 abs_top_srcdir = @abs_top_srcdir@
+ac_ct_AR = @ac_ct_AR@
 ac_ct_CC = @ac_ct_CC@
 ac_ct_DUMPBIN = @ac_ct_DUMPBIN@
 am__include = @am__include@
@@ -283,7 +278,6 @@ libdir = @libdir@
 libexecdir = @libexecdir@
 localedir = @localedir@
 localstatedir = @localstatedir@
-lt_ECHO = @lt_ECHO@
 mandir = @mandir@
 mkdir_p = @mkdir_p@
 oldincludedir = @oldincludedir@
@@ -306,11 +300,16 @@ top_srcdir = @top_srcdir@
 PNGLIB_BASENAME = libpng@PNGLIB_MAJOR@@PNGLIB_MINOR@

 # libpng does not follow GNU file name conventions
-AUTOMAKE_OPTIONS = foreign color-tests
+
+# "color-tests" requires automake 1.11.1 or later.  Enable it if you like,
+# to get red "FAIL" and green "PASS" notations during tests.
+# AUTOMAKE_OPTIONS = foreign color-tests
+AUTOMAKE_OPTIONS = foreign
 pngtest_SOURCES = pngtest.c
 pngtest_LDADD = libpng@PNGLIB_MAJOR@@PNGLIB_MINOR@.la
 pngvalid_SOURCES = pngvalid.c
 pngvalid_LDADD = libpng@PNGLIB_MAJOR@@PNGLIB_MINOR@.la
+TESTS = test-pngtest.sh test-pngvalid-simple.sh test-pngvalid-full.sh
 TESTS_ENVIRONMENT = srcdir=$(srcdir) 

 # man pages
@@ -349,16 +348,21 @@ EXTRA_DIST = \
 SCRIPT_CLEANFILES = scripts/*.out scripts/*.chk scripts/pnglibconf.dfn
 CLEANFILES = dfn.c dfn?.out pngout.png libpng@PNGLIB_MAJOR@@PNGLIB_MINOR@.pc \
 	libpng@PNGLIB_MAJOR@@PNGLIB_MINOR@-config libpng.vers libpng.sym \
-	pngwin.def check.new pnglibconf.* symbols.new \
+	check.new pnglibconf.* symbols.new pngtest-log.txt \
 	$(SCRIPT_CLEANFILES)

 MAINTAINERCLEANFILES = Makefile.in aclocal.m4 config.guess config.h.in \
 config.sub configure depcomp install-sh ltmain.sh missing

 SUFFIXES = .chk .dfn .out
+
+# We must use -DPNG_NO_USE_READ_MACROS here even when the library may actually
+# be built with PNG_USE_READ_MACROS; this stops the read macros interfering
+# with the symbol file format.
 SYMBOL_CFLAGS = -DPNGLIB_LIBNAME='PNG@PNGLIB_MAJOR@@PNGLIB_MINOR@_0'\
 		-DPNGLIB_VERSION='@PNGLIB_VERSION@'\
-		-DSYMBOL_PREFIX='$(SYMBOL_PREFIX)'
+		-DSYMBOL_PREFIX='$(SYMBOL_PREFIX)'\
+		-DPNG_NO_USE_READ_MACROS

 all: config.h
 	$(MAKE) $(AM_MAKEFLAGS) all-am
@@ -1261,7 +1265,7 @@ $(PNGLIB_BASENAME)-config: libpng-config
 	cp libpng-config $@

 scripts/sym.out scripts/vers.out: png.h pngconf.h pnglibconf.h
-scripts/symbols.out scripts/pngwin.out: png.h pngconf.h scripts/pnglibconf.h.prebuilt
+scripts/symbols.out: png.h pngconf.h scripts/pnglibconf.h.prebuilt

 libpng.sym: scripts/sym.out
 	rm -f $@
@@ -1269,9 +1273,6 @@ libpng.sym: scripts/sym.out
 libpng.vers: scripts/vers.out
 	rm -f $@
 	cp $? $@
-pngwin.def: scripts/pngwin.out
-	rm -f $@
-	cp $? $@
 pnglibconf.h: pnglibconf.out
 	rm -f $@
 	cp $? $@
@@ -1289,7 +1290,7 @@ pngvalid.o pngtest.o: pnglibconf.h
 	rm -f $@ dfn.c dfn?.out
 	test -d scripts || mkdir scripts
 	echo '#include "$<"' >dfn.c
-	$(CPP) $(DEFS) $(DEFAULT_INCLUDES) $(INCLUDES) @LIBPNG_DEFINES@\
+	$(DFNCPP) $(DEFS) $(DEFAULT_INCLUDES) $(INCLUDES) @LIBPNG_DEFINES@\
 	    $(CPPFLAGS) $(SYMBOL_CFLAGS) dfn.c > dfn1.out
 	$(SED) -n -e 's|^.*PNG_DEFN_MAGIC-\(.*\)-PNG_DEFN_END.*$$|\1|p'\
 	    dfn1.out >dfn2.out
@@ -1307,7 +1308,6 @@ pnglibconf.dfn: scripts/pnglibconf.dfa scripts/options.awk
 	mv dfn2.out $@

 # Symbol checks (.def and .out files should match)
-scripts/pngwin.chk: scripts/checksym.awk scripts/pngwin.def scripts/pngwin.out
 scripts/symbols.chk: scripts/checksym.awk scripts/symbols.def scripts/symbols.out
 .out.chk:
 	rm -f $@ symbols.new
@@ -1333,7 +1333,7 @@ $(libpng@PNGLIB_MAJOR@@PNGLIB_MINOR@_la_OBJECTS): png.h pngconf.h \
 test: check-am

 # Extra checks
-check: scripts/symbols.chk scripts/pngwin.chk
+check: scripts/symbols.chk

 # Don't distribute the generated script files
 dist-hook:
--- a/2
+++ b/2
@@ -1,4 +1,4 @@
-README for libpng version 1.5.0beta55 - November 21, 2010 (shared library 15.0)
+README for libpng version 1.5.2rc01 - March 19, 2011 (shared library 15.0)
 See the note about version numbers near the top of png.h

 See INSTALL for instructions on how to install libpng.
--- a/aclocal.m4
+++ b/aclocal.m4
--- a/config.guess
+++ b/config.guess
@@ -1,10 +1,10 @@
 #! /bin/sh
 # Attempt to guess a canonical system name.
 #   Copyright (C) 1992, 1993, 1994, 1995, 1996, 1997, 1998, 1999,
-#   2000, 2001, 2002, 2003, 2004, 2005, 2006, 2007, 2008
+#   2000, 2001, 2002, 2003, 2004, 2005, 2006, 2007, 2008, 2009
 #   Free Software Foundation, Inc.

-timestamp='2009-04-27'
+timestamp='2009-11-20'

 # This file is free software; you can redistribute it and/or modify it
 # under the terms of the GNU General Public License as published by
@@ -27,16 +27,16 @@ timestamp='2009-04-27'
 # the same distribution terms that you use for the rest of that program.


-# Originally written by Per Bothner <per@bothner.com>.
-# Please send patches to <config-patches@gnu.org>.  Submit a context
-# diff and a properly formatted ChangeLog entry.
+# Originally written by Per Bothner.  Please send patches (context
+# diff format) to <config-patches@gnu.org> and include a ChangeLog
+# entry.
 #
 # This script attempts to guess a canonical system name similar to
 # config.sub.  If it succeeds, it prints the system name on stdout, and
 # exits with 0.  Otherwise, it exits with 1.
 #
-# The plan is that this can be called by configure scripts if you
-# don't specify an explicit build system type.
+# You can get the latest version of this script from:
+# http://git.savannah.gnu.org/gitweb/?p=config.git;a=blob_plain;f=config.guess;hb=HEAD

 me=`echo "$0" | sed -e 's,.*/,,'`

@@ -170,7 +170,7 @@ case "${UNAME_MACHINE}:${UNAME_SYSTEM}:${UNAME_RELEASE}:${UNAME_VERSION}" in
 	    arm*|i386|m68k|ns32k|sh3*|sparc|vax)
 		eval $set_cc_for_build
 		if echo __ELF__ | $CC_FOR_BUILD -E - 2>/dev/null \
-			| grep __ELF__ >/dev/null
+			| grep -q __ELF__
 		then
 		    # Once all utilities can be ECOFF (netbsdecoff) or a.out (netbsdaout).
 		    # Return netbsd for either.  FIX?
@@ -333,6 +333,9 @@ case "${UNAME_MACHINE}:${UNAME_SYSTEM}:${UNAME_RELEASE}:${UNAME_VERSION}" in
    sun4*:SunOS:5.*:* | tadpole*:SunOS:5.*:*)
 	echo sparc-sun-solaris2`echo ${UNAME_RELEASE}|sed -e 's/[^.]*//'`
 	exit ;;
+    i86pc:AuroraUX:5.*:* | i86xen:AuroraUX:5.*:*)
+	echo i386-pc-auroraux${UNAME_RELEASE}
+	exit ;;
    i86pc:SunOS:5.*:* | i86xen:SunOS:5.*:*)
 	eval $set_cc_for_build
 	SUN_ARCH="i386"
@@ -656,7 +659,7 @@ EOF
 	    # => hppa64-hp-hpux11.23

 	    if echo __LP64__ | (CCOPTS= $CC_FOR_BUILD -E - 2>/dev/null) |
-		grep __LP64__ >/dev/null
+		grep -q __LP64__
 	    then
 		HP_ARCH="hppa2.0w"
 	    else
@@ -807,12 +810,12 @@ EOF
    i*:PW*:*)
 	echo ${UNAME_MACHINE}-pc-pw32
 	exit ;;
-    *:Interix*:[3456]*)
+    *:Interix*:*)
    	case ${UNAME_MACHINE} in
 	    x86)
 		echo i586-pc-interix${UNAME_RELEASE}
 		exit ;;
-	    EM64T | authenticamd | genuineintel)
+	    authenticamd | genuineintel | EM64T)
 		echo x86_64-unknown-interix${UNAME_RELEASE}
 		exit ;;
 	    IA64)
@@ -822,6 +825,9 @@ EOF
    [345]86:Windows_95:* | [345]86:Windows_98:* | [345]86:Windows_NT:*)
 	echo i${UNAME_MACHINE}-pc-mks
 	exit ;;
+    8664:Windows_NT:*)
+	echo x86_64-pc-mks
+	exit ;;
    i*:Windows_NT*:* | Pentium*:Windows_NT*:*)
 	# How do we know it's Interix rather than the generic POSIX subsystem?
 	# It also conflicts with pre-2.0 versions of AT&T UWIN. Should we
@@ -851,6 +857,20 @@ EOF
    i*86:Minix:*:*)
 	echo ${UNAME_MACHINE}-pc-minix
 	exit ;;
+    alpha:Linux:*:*)
+	case `sed -n '/^cpu model/s/^.*: \(.*\)/\1/p' < /proc/cpuinfo` in
+	  EV5)   UNAME_MACHINE=alphaev5 ;;
+	  EV56)  UNAME_MACHINE=alphaev56 ;;
+	  PCA56) UNAME_MACHINE=alphapca56 ;;
+	  PCA57) UNAME_MACHINE=alphapca56 ;;
+	  EV6)   UNAME_MACHINE=alphaev6 ;;
+	  EV67)  UNAME_MACHINE=alphaev67 ;;
+	  EV68*) UNAME_MACHINE=alphaev68 ;;
+        esac
+	objdump --private-headers /bin/sh | grep -q ld.so.1
+	if test "$?" = 0 ; then LIBC="libc1" ; else LIBC="" ; fi
+	echo ${UNAME_MACHINE}-unknown-linux-gnu${LIBC}
+	exit ;;
    arm*:Linux:*:*)
 	eval $set_cc_for_build
 	if echo __ARM_EABI__ | $CC_FOR_BUILD -E - 2>/dev/null \
@@ -873,6 +893,17 @@ EOF
    frv:Linux:*:*)
    	echo frv-unknown-linux-gnu
 	exit ;;
+    i*86:Linux:*:*)
+	LIBC=gnu
+	eval $set_cc_for_build
+	sed 's/^	//' << EOF >$dummy.c
+	#ifdef __dietlibc__
+	LIBC=dietlibc
+	#endif
+EOF
+	eval `$CC_FOR_BUILD -E $dummy.c 2>/dev/null | grep '^LIBC'`
+	echo "${UNAME_MACHINE}-pc-linux-${LIBC}"
+	exit ;;
    ia64:Linux:*:*)
 	echo ${UNAME_MACHINE}-unknown-linux-gnu
 	exit ;;
@@ -882,78 +913,34 @@ EOF
    m68*:Linux:*:*)
 	echo ${UNAME_MACHINE}-unknown-linux-gnu
 	exit ;;
-    mips:Linux:*:*)
+    mips:Linux:*:* | mips64:Linux:*:*)
 	eval $set_cc_for_build
 	sed 's/^	//' << EOF >$dummy.c
 	#undef CPU
-	#undef mips
-	#undef mipsel
+	#undef ${UNAME_MACHINE}
+	#undef ${UNAME_MACHINE}el
 	#if defined(__MIPSEL__) || defined(__MIPSEL) || defined(_MIPSEL) || defined(MIPSEL)
-	CPU=mipsel
+	CPU=${UNAME_MACHINE}el
 	#else
 	#if defined(__MIPSEB__) || defined(__MIPSEB) || defined(_MIPSEB) || defined(MIPSEB)
-	CPU=mips
+	CPU=${UNAME_MACHINE}
 	#else
 	CPU=
 	#endif
 	#endif
 EOF
-	eval "`$CC_FOR_BUILD -E $dummy.c 2>/dev/null | sed -n '
-	    /^CPU/{
-		s: ::g
-		p
-	    }'`"
-	test x"${CPU}" != x && { echo "${CPU}-unknown-linux-gnu"; exit; }
-	;;
-    mips64:Linux:*:*)
-	eval $set_cc_for_build
-	sed 's/^	//' << EOF >$dummy.c
-	#undef CPU
-	#undef mips64
-	#undef mips64el
-	#if defined(__MIPSEL__) || defined(__MIPSEL) || defined(_MIPSEL) || defined(MIPSEL)
-	CPU=mips64el
-	#else
-	#if defined(__MIPSEB__) || defined(__MIPSEB) || defined(_MIPSEB) || defined(MIPSEB)
-	CPU=mips64
-	#else
-	CPU=
-	#endif
-	#endif
-EOF
-	eval "`$CC_FOR_BUILD -E $dummy.c 2>/dev/null | sed -n '
-	    /^CPU/{
-		s: ::g
-		p
-	    }'`"
+	eval `$CC_FOR_BUILD -E $dummy.c 2>/dev/null | grep '^CPU'`
 	test x"${CPU}" != x && { echo "${CPU}-unknown-linux-gnu"; exit; }
 	;;
    or32:Linux:*:*)
 	echo or32-unknown-linux-gnu
 	exit ;;
-    ppc:Linux:*:*)
-	echo powerpc-unknown-linux-gnu
-	exit ;;
-    ppc64:Linux:*:*)
-	echo powerpc64-unknown-linux-gnu
-	exit ;;
-    alpha:Linux:*:*)
-	case `sed -n '/^cpu model/s/^.*: \(.*\)/\1/p' < /proc/cpuinfo` in
-	  EV5)   UNAME_MACHINE=alphaev5 ;;
-	  EV56)  UNAME_MACHINE=alphaev56 ;;
-	  PCA56) UNAME_MACHINE=alphapca56 ;;
-	  PCA57) UNAME_MACHINE=alphapca56 ;;
-	  EV6)   UNAME_MACHINE=alphaev6 ;;
-	  EV67)  UNAME_MACHINE=alphaev67 ;;
-	  EV68*) UNAME_MACHINE=alphaev68 ;;
-        esac
-	objdump --private-headers /bin/sh | grep ld.so.1 >/dev/null
-	if test "$?" = 0 ; then LIBC="libc1" ; else LIBC="" ; fi
-	echo ${UNAME_MACHINE}-unknown-linux-gnu${LIBC}
-	exit ;;
    padre:Linux:*:*)
 	echo sparc-unknown-linux-gnu
 	exit ;;
+    parisc64:Linux:*:* | hppa64:Linux:*:*)
+	echo hppa64-unknown-linux-gnu
+	exit ;;
    parisc:Linux:*:* | hppa:Linux:*:*)
 	# Look for CPU level
 	case `grep '^cpu[^a-z]*:' /proc/cpuinfo 2>/dev/null | cut -d' ' -f2` in
@@ -962,8 +949,11 @@ EOF
 	  *)    echo hppa-unknown-linux-gnu ;;
 	esac
 	exit ;;
-    parisc64:Linux:*:* | hppa64:Linux:*:*)
-	echo hppa64-unknown-linux-gnu
+    ppc64:Linux:*:*)
+	echo powerpc64-unknown-linux-gnu
+	exit ;;
+    ppc:Linux:*:*)
+	echo powerpc-unknown-linux-gnu
 	exit ;;
    s390:Linux:*:* | s390x:Linux:*:*)
 	echo ${UNAME_MACHINE}-ibm-linux
@@ -986,66 +976,6 @@ EOF
    xtensa*:Linux:*:*)
    	echo ${UNAME_MACHINE}-unknown-linux-gnu
 	exit ;;
-    i*86:Linux:*:*)
-	# The BFD linker knows what the default object file format is, so
-	# first see if it will tell us. cd to the root directory to prevent
-	# problems with other programs or directories called `ld' in the path.
-	# Set LC_ALL=C to ensure ld outputs messages in English.
-	ld_supported_targets=`cd /; LC_ALL=C ld --help 2>&1 \
-			 | sed -ne '/supported targets:/!d
-				    s/[ 	][ 	]*/ /g
-				    s/.*supported targets: *//
-				    s/ .*//
-				    p'`
-        case "$ld_supported_targets" in
-	  elf32-i386)
-		TENTATIVE="${UNAME_MACHINE}-pc-linux-gnu"
-		;;
-	  a.out-i386-linux)
-		echo "${UNAME_MACHINE}-pc-linux-gnuaout"
-		exit ;;
-	  "")
-		# Either a pre-BFD a.out linker (linux-gnuoldld) or
-		# one that does not give us useful --help.
-		echo "${UNAME_MACHINE}-pc-linux-gnuoldld"
-		exit ;;
-	esac
-	# Determine whether the default compiler is a.out or elf
-	eval $set_cc_for_build
-	sed 's/^	//' << EOF >$dummy.c
-	#include <features.h>
-	#ifdef __ELF__
-	# ifdef __GLIBC__
-	#  if __GLIBC__ >= 2
-	LIBC=gnu
-	#  else
-	LIBC=gnulibc1
-	#  endif
-	# else
-	LIBC=gnulibc1
-	# endif
-	#else
-	#if defined(__INTEL_COMPILER) || defined(__PGI) || defined(__SUNPRO_C) || defined(__SUNPRO_CC)
-	LIBC=gnu
-	#else
-	LIBC=gnuaout
-	#endif
-	#endif
-	#ifdef __dietlibc__
-	LIBC=dietlibc
-	#endif
-EOF
-	eval "`$CC_FOR_BUILD -E $dummy.c 2>/dev/null | sed -n '
-	    /^LIBC/{
-		s: ::g
-		p
-	    }'`"
-	test x"${LIBC}" != x && {
-		echo "${UNAME_MACHINE}-pc-linux-${LIBC}"
-		exit
-	}
-	test x"${TENTATIVE}" != x && { echo "${TENTATIVE}"; exit; }
-	;;
    i*86:DYNIX/ptx:4*:*)
 	# ptx 4.0 does uname -s correctly, with DYNIX/ptx in there.
 	# earlier versions are messed up and put the nodename in both
@@ -1074,7 +1004,7 @@ EOF
    i*86:syllable:*:*)
 	echo ${UNAME_MACHINE}-pc-syllable
 	exit ;;
-    i*86:LynxOS:2.*:* | i*86:LynxOS:3.[01]*:* | i*86:LynxOS:4.0*:*)
+    i*86:LynxOS:2.*:* | i*86:LynxOS:3.[01]*:* | i*86:LynxOS:4.[02]*:*)
 	echo i386-unknown-lynxos${UNAME_RELEASE}
 	exit ;;
    i*86:*DOS:*:*)
@@ -1182,7 +1112,7 @@ EOF
    rs6000:LynxOS:2.*:*)
 	echo rs6000-unknown-lynxos${UNAME_RELEASE}
 	exit ;;
-    PowerPC:LynxOS:2.*:* | PowerPC:LynxOS:3.[01]*:* | PowerPC:LynxOS:4.0*:*)
+    PowerPC:LynxOS:2.*:* | PowerPC:LynxOS:3.[01]*:* | PowerPC:LynxOS:4.[02]*:*)
 	echo powerpc-unknown-lynxos${UNAME_RELEASE}
 	exit ;;
    SM[BE]S:UNIX_SV:*:*)
@@ -1275,6 +1205,16 @@ EOF
    *:Darwin:*:*)
 	UNAME_PROCESSOR=`uname -p` || UNAME_PROCESSOR=unknown
 	case $UNAME_PROCESSOR in
+	    i386)
+		eval $set_cc_for_build
+		if [ "$CC_FOR_BUILD" != 'no_compiler_found' ]; then
+		  if (echo '#ifdef __LP64__'; echo IS_64BIT_ARCH; echo '#endif') | \
+		      (CCOPTS= $CC_FOR_BUILD -E - 2>/dev/null) | \
+		      grep IS_64BIT_ARCH >/dev/null
+		  then
+		      UNAME_PROCESSOR="x86_64"
+		  fi
+		fi ;;
 	    unknown) UNAME_PROCESSOR=powerpc ;;
 	esac
 	echo ${UNAME_PROCESSOR}-apple-darwin${UNAME_RELEASE}
--- a/config.sub
+++ b/config.sub
@@ -1,10 +1,10 @@
 #! /bin/sh
 # Configuration validation subroutine script.
 #   Copyright (C) 1992, 1993, 1994, 1995, 1996, 1997, 1998, 1999,
-#   2000, 2001, 2002, 2003, 2004, 2005, 2006, 2007, 2008
+#   2000, 2001, 2002, 2003, 2004, 2005, 2006, 2007, 2008, 2009
 #   Free Software Foundation, Inc.

-timestamp='2009-04-17'
+timestamp='2009-11-20'

 # This file is (in principle) common to ALL GNU software.
 # The presence of a machine in this file suggests that SOME GNU software
@@ -32,13 +32,16 @@ timestamp='2009-04-17'


 # Please send patches to <config-patches@gnu.org>.  Submit a context
-# diff and a properly formatted ChangeLog entry.
+# diff and a properly formatted GNU ChangeLog entry.
 #
 # Configuration subroutine to validate and canonicalize a configuration type.
 # Supply the specified configuration type as an argument.
 # If it is invalid, we print an error message on stderr and exit with code 1.
 # Otherwise, we print the canonical config type on stdout and succeed.

+# You can get the latest version of this script from:
+# http://git.savannah.gnu.org/gitweb/?p=config.git;a=blob_plain;f=config.sub;hb=HEAD
+
 # This file is supposed to be the same for all GNU packages
 # and recognize all the CPU types, system types and aliases
 # that are meaningful with *any* GNU software.
@@ -149,10 +152,13 @@ case $os in
 	-convergent* | -ncr* | -news | -32* | -3600* | -3100* | -hitachi* |\
 	-c[123]* | -convex* | -sun | -crds | -omron* | -dg | -ultra | -tti* | \
 	-harris | -dolphin | -highlevel | -gould | -cbm | -ns | -masscomp | \
-	-apple | -axis | -knuth | -cray)
+	-apple | -axis | -knuth | -cray | -microblaze)
 		os=
 		basic_machine=$1
 		;;
+        -bluegene*)
+	        os=-cnk
+		;;
 	-sim | -cisco | -oki | -wec | -winbond)
 		os=
 		basic_machine=$1
@@ -281,6 +287,7 @@ case $basic_machine in
 	| pdp10 | pdp11 | pj | pjl \
 	| powerpc | powerpc64 | powerpc64le | powerpcle | ppcbe \
 	| pyramid \
+	| rx \
 	| score \
 	| sh | sh[1234] | sh[24]a | sh[24]aeb | sh[23]e | sh[34]eb | sheb | shbe | shle | sh[1234]le | sh3ele \
 	| sh64 | sh64le \
@@ -288,13 +295,14 @@ case $basic_machine in
 	| sparcv8 | sparcv9 | sparcv9b | sparcv9v \
 	| spu | strongarm \
 	| tahoe | thumb | tic4x | tic80 | tron \
+	| ubicom32 \
 	| v850 | v850e \
 	| we32k \
 	| x86 | xc16x | xscale | xscalee[bl] | xstormy16 | xtensa \
 	| z8k | z80)
 		basic_machine=$basic_machine-unknown
 		;;
-	m6811 | m68hc11 | m6812 | m68hc12)
+	m6811 | m68hc11 | m6812 | m68hc12 | picochip)
 		# Motorola 68HC11/12.
 		basic_machine=$basic_machine-unknown
 		os=-none
@@ -337,7 +345,7 @@ case $basic_machine in
 	| lm32-* \
 	| m32c-* | m32r-* | m32rle-* \
 	| m68000-* | m680[012346]0-* | m68360-* | m683?2-* | m68k-* \
-	| m88110-* | m88k-* | maxq-* | mcore-* | metag-* \
+	| m88110-* | m88k-* | maxq-* | mcore-* | metag-* | microblaze-* \
 	| mips-* | mipsbe-* | mipseb-* | mipsel-* | mipsle-* \
 	| mips16-* \
 	| mips64-* | mips64el-* \
@@ -365,7 +373,7 @@ case $basic_machine in
 	| pdp10-* | pdp11-* | pj-* | pjl-* | pn-* | power-* \
 	| powerpc-* | powerpc64-* | powerpc64le-* | powerpcle-* | ppcbe-* \
 	| pyramid-* \
-	| romp-* | rs6000-* \
+	| romp-* | rs6000-* | rx-* \
 	| sh-* | sh[1234]-* | sh[24]a-* | sh[24]aeb-* | sh[23]e-* | sh[34]eb-* | sheb-* | shbe-* \
 	| shle-* | sh[1234]le-* | sh3ele-* | sh64-* | sh64le-* \
 	| sparc-* | sparc64-* | sparc64b-* | sparc64v-* | sparc86x-* | sparclet-* \
@@ -374,6 +382,7 @@ case $basic_machine in
 	| tahoe-* | thumb-* \
 	| tic30-* | tic4x-* | tic54x-* | tic55x-* | tic6x-* | tic80-* | tile-* \
 	| tron-* \
+	| ubicom32-* \
 	| v850-* | v850e-* | vax-* \
 	| we32k-* \
 	| x86-* | x86_64-* | xc16x-* | xps100-* | xscale-* | xscalee[bl]-* \
@@ -467,6 +476,10 @@ case $basic_machine in
 		basic_machine=bfin-`echo $basic_machine | sed 's/^[^-]*-//'`
 		os=-linux
 		;;
+	bluegene*)
+		basic_machine=powerpc-ibm
+		os=-cnk
+		;;
 	c90)
 		basic_machine=c90-cray
 		os=-unicos
@@ -719,6 +732,9 @@ case $basic_machine in
 		basic_machine=ns32k-utek
 		os=-sysv
 		;;
+        microblaze)
+		basic_machine=microblaze-xilinx
+		;;
 	mingw32)
 		basic_machine=i386-pc
 		os=-mingw32
@@ -1240,6 +1256,9 @@ case $os in
        # First match some system type aliases
        # that might get confused with valid system types.
 	# -solaris* is a basic system type, with this one exception.
+        -auroraux)
+	        os=-auroraux
+		;;
 	-solaris1 | -solaris1.*)
 		os=`echo $os | sed -e 's|solaris1|sunos4|'`
 		;;
@@ -1260,9 +1279,9 @@ case $os in
 	# Each alternative MUST END IN A *, to match a version number.
 	# -sysv* is not here because it comes later, after sysvr4.
 	-gnu* | -bsd* | -mach* | -minix* | -genix* | -ultrix* | -irix* \
-	      | -*vms* | -sco* | -esix* | -isc* | -aix* | -sunos | -sunos[34]*\
-	      | -hpux* | -unos* | -osf* | -luna* | -dgux* | -solaris* | -sym* \
-	      | -kopensolaris* \
+	      | -*vms* | -sco* | -esix* | -isc* | -aix* | -cnk* | -sunos | -sunos[34]*\
+	      | -hpux* | -unos* | -osf* | -luna* | -dgux* | -auroraux* | -solaris* \
+	      | -sym* | -kopensolaris* \
 	      | -amigaos* | -amigados* | -msdos* | -newsos* | -unicos* | -aof* \
 	      | -aos* | -aros* \
 	      | -nindy* | -vxsim* | -vxworks* | -ebmon* | -hms* | -mvs* \
@@ -1283,7 +1302,7 @@ case $os in
 	      | -os2* | -vos* | -palmos* | -uclinux* | -nucleus* \
 	      | -morphos* | -superux* | -rtmk* | -rtmk-nova* | -windiss* \
 	      | -powermax* | -dnix* | -nx6 | -nx7 | -sei* | -dragonfly* \
-	      | -skyos* | -haiku* | -rdos* | -toppers* | -drops*)
+	      | -skyos* | -haiku* | -rdos* | -toppers* | -drops* | -es*)
 	# Remember, each alternative MUST END IN *, to match a version number.
 		;;
 	-qnx*)
@@ -1613,7 +1632,7 @@ case $basic_machine in
 			-sunos*)
 				vendor=sun
 				;;
-			-aix*)
+			-cnk*|-aix*)
 				vendor=ibm
 				;;
 			-beos*)
--- a/2070
+++ b/2070
--- a/configure.ac
+++ b/configure.ac
@@ -18,15 +18,15 @@ AC_PREREQ(2.59)

 dnl Version number stuff here:

-AC_INIT([libpng], [1.5.0beta55], [png-mng-implement@lists.sourceforge.net])
+AC_INIT([libpng], [1.5.2rc01], [png-mng-implement@lists.sourceforge.net])
 AM_INIT_AUTOMAKE
 dnl stop configure from automagically running automake
 AM_MAINTAINER_MODE

-PNGLIB_VERSION=1.5.0beta55
+PNGLIB_VERSION=1.5.2rc01
 PNGLIB_MAJOR=1
 PNGLIB_MINOR=5
-PNGLIB_RELEASE=0
+PNGLIB_RELEASE=2

 dnl End of version number stuff

@@ -34,6 +34,7 @@ AC_CONFIG_SRCDIR([pngget.c])
 AM_CONFIG_HEADER(config.h)

 # Checks for programs.
+AC_LANG([C])
 AC_PROG_CC
 AC_PROG_LD
 AC_PROG_CPP
@@ -44,6 +45,28 @@ AC_PROG_LN_S
 AC_PROG_MAKE_SET
 LT_INIT([win32-dll])

+# On Solaris 10 and 12 CPP gets set to cc -E, however this still
+# does some input parsing.  We need strict ANSI-C style tokenization,
+# check this:
+AC_REQUIRE_CPP
+AC_MSG_CHECKING([for a C preprocessor that does not parse its input])
+AC_TRY_CPP([1.5.0 16BIT],
+   [DFNCPP="$CPP"],
+   [DFNCPP=""
+   sav_CPP="$CPP"
+   for CPP in "${CC-cc} -E" "${CC-cc} -E -traditional-cpp" "/lib/cpp" "cpp"; do
+      AC_TRY_CPP([1.5.0 16BIT],
+         [DFNCPP="$CPP"]
+         [break],,)
+   done
+   CPP="$sav_CPP"])
+if test -n "$DFNCPP"; then
+   AC_MSG_RESULT([$DFNCPP])
+   AC_SUBST(DFNCPP)
+else
+   AC_MSG_FAILURE([not found], 1)
+fi
+
 # Checks for header files.
 AC_HEADER_STDC
 AC_CHECK_HEADERS([malloc.h stdlib.h string.h strings.h])
@@ -57,7 +80,15 @@ AC_STRUCT_TM
 AC_FUNC_STRTOD
 AC_CHECK_FUNCS([memset], , AC_ERROR([memset not found in libc]))
 AC_CHECK_FUNCS([pow], , AC_CHECK_LIB(m, pow, , AC_ERROR([cannot find pow])) )
-AC_CHECK_LIB(z, zlibVersion, , AC_ERROR([zlib not installed]))
+AC_ARG_WITH(zlib-prefix,
+   AC_HELP_STRING([--with-zlib-prefix],
+                  [prefix that may have been used in installed zlib]),
+                  [ZPREFIX=${withval}],
+                  [ZPREFIX='z_'])
+AC_CHECK_LIB(z, zlibVersion, ,
+    AC_CHECK_LIB(z, ${ZPREFIX}zlibVersion, ,
+                 AC_ERROR([zlib not installed])))
+

 LIBPNG_DEFINES=-DPNG_CONFIGURE_LIBPNG
 LIBPNG_DEFINES=$LIBPNG_DEFINES
@@ -68,7 +99,7 @@ AC_MSG_CHECKING([if libraries can be versioned])
 # support for version-script, but doesn't actually
 # DO anything with it.
 case $host in
-*cygwin* | *mingw32* )
+*cygwin* | *mingw32* | *interix* )
    have_ld_version_script=no
    AC_MSG_RESULT(no)
 ;;
--- a/contrib/pngminim/decoder/pngusr.dfa
+++ b/contrib/pngminim/decoder/pngusr.dfa
@@ -1,6 +1,6 @@
 # pngminim/decoder/pngusr.dfa
 #
-# Copyright (c) 2010 Glenn Randers-Pehrson
+# Copyright (c) 2010-2011 Glenn Randers-Pehrson
 #
 # This code is released under the libpng license.
 # For conditions of distribution and use, see the disclaimer
--- a/contrib/pngminim/decoder/pngusr.h
+++ b/contrib/pngminim/decoder/pngusr.h
@@ -1,6 +1,6 @@
 /* minrdpngconf.h: headers to make a minimal png-read-only library
 *
- * Copyright (c) 2007, 2010 Glenn Randers-Pehrson
+ * Copyright (c) 2007, 2010-2011 Glenn Randers-Pehrson
 *
 * This code is released under the libpng license.
 * For conditions of distribution and use, see the disclaimer
--- a/contrib/pngminim/encoder/pngusr.dfa
+++ b/contrib/pngminim/encoder/pngusr.dfa
@@ -1,6 +1,6 @@
 # pngminim/encoder/pngusr.dfa
 #
-# Copyright (c) 2010 Glenn Randers-Pehrson
+# Copyright (c) 2010-2011 Glenn Randers-Pehrson
 #
 # This code is released under the libpng license.
 # For conditions of distribution and use, see the disclaimer
--- a/contrib/pngminim/encoder/pngusr.h
+++ b/contrib/pngminim/encoder/pngusr.h
@@ -1,6 +1,6 @@
 /* minwrpngconf.h: headers to make a minimal png-write-only library
 *
- * Copyright (c) 2007, 2010 Glenn Randers-Pehrson
+ * Copyright (c) 2007, 2010-2011 Glenn Randers-Pehrson
 *
 * This code is released under the libpng license.
 * For conditions of distribution and use, see the disclaimer
--- a/contrib/pngminim/preader/pngusr.dfa
+++ b/contrib/pngminim/preader/pngusr.dfa
@@ -1,6 +1,6 @@
 # pngminim/preader/pngusr.dfa
 #
-# Copyright (c) 2010 Glenn Randers-Pehrson
+# Copyright (c) 2010-2011 Glenn Randers-Pehrson
 #
 # This code is released under the libpng license.
 # For conditions of distribution and use, see the disclaimer
--- a/contrib/pngminim/preader/pngusr.h
+++ b/contrib/pngminim/preader/pngusr.h
@@ -1,6 +1,6 @@
 /* minrdpngconf.h: headers to make a minimal png-read-only library
 *
- * Copyright (c) 2009, 2010 Glenn Randers-Pehrson
+ * Copyright (c) 2009, 2010-2011 Glenn Randers-Pehrson
 *
 * This code is released under the libpng license.
 * For conditions of distribution and use, see the disclaimer
--- a/contrib/pngsuite/README
+++ b/contrib/pngsuite/README
@@ -1,10 +1,10 @@

 pngsuite
 --------
-(c) Willem van Schaik, 1999
+(c) Willem van Schaik, 1999, 2011

-Permission to use, copy, and distribute these images for any purpose and
-without fee is hereby granted.
+Permission to use, copy, modify, and distribute these images for any
+purpose and without fee is hereby granted.

 The 15 "bas*.png" images are part of the much larger PngSuite test-set of 
 images, available for developers of PNG supporting software. The 
@@ -52,7 +52,7 @@ can use them to test the proper functioning of PNG software.
    ftp0n3p08.png  8-bit paletted, opaque
    ftp1n3p08.png  8-bit paletted, no bKGD

-Here is the correct result of typing "pngtest -m *.png" in
+Here is the correct result of typing "pngtest -m bas*.png" in
 this directory:

 Testing basn0g01.png: PASS (524 zero samples)
--- a/example.c
+++ b/example.c
@@ -2,9 +2,9 @@
 #if 0 /* in case someone actually tries to compile this */

 /* example.c - an example of using libpng
- * Last changed in libpng 1.5.0 [(PENDING RELEASE)]
+ * Last changed in libpng 1.5.0 [January 6, 2011]
 * This file has been placed in the public domain by the authors.
- * Maintained 1998-2010 Glenn Randers-Pehrson
+ * Maintained 1998-2011 Glenn Randers-Pehrson
 * Maintained 1996, 1997 Andreas Dilger)
 * Written 1995, 1996 Guy Eric Schalnat, Group 42, Inc.)
 */
--- a/libpng-manual.txt
+++ b/libpng-manual.txt
--- a/libpng.3
+++ b/libpng.3
--- a/libpngpf.3
+++ b/libpngpf.3
@@ -1,908 +1,24 @@
-.TH LIBPNGPF 3 "November 21, 2010"
+.TH LIBPNGPF 3 "March 19, 2011"
 .SH NAME
-libpng \- Portable Network Graphics (PNG) Reference Library 1.5.0beta55
+libpng \- Portable Network Graphics (PNG) Reference Library 1.5.2rc01
 (private functions)
 .SH SYNOPSIS
 \fB#include \fI"pngpriv.h"

 \fI\fB

-\fBvoid png_64bit_product (long \fP\fIv1\fP\fB, long \fP\fIv2\fP\fB, unsigned long \fP\fI*hi_product\fP\fB, unsigned long \fI*lo_product\fP\fB);\fP
+\fBAs of libpng version \fP\fI1.5.1\fP\fB, this section is no longer \fP\fImaintained\fP\fB, now \fIthat

-\fI\fB
+\fBthe private function prototypes are hidden in pngpriv.h and not \fIaccessible

-\fI\fB
+\fBto applications. Look in pngpriv.h for the prototypes and a short \fIdescription

-\fBvoid png_ascii_from_fp (png_structp \fP\fIpng_ptr\fP\fB, png_charp \fP\fIascii\fP\fB, png_size_t \fP\fIsize\fP\fB, double \fP\fIfp\fP\fB, unsigned \fIprecision\fP\fB);\fP
-
-\fI\fB
-
-\fI\fB
-
-\fBvoid png_build_gamma_table (png_structp \fP\fIpng_ptr\fP\fB, png_byte \fIbit_depth\fP\fB);\fP
-
-\fI\fB
-
-\fI\fB
-
-\fBvoid png_build_grayscale_palette (int \fP\fIbit_depth\fP\fB, png_colorp \fIpalette\fP\fB);\fP
-
-\fI\fB
-
-\fI\fB
-
-\fBvoid png_calculate_crc (png_structp \fP\fIpng_ptr\fP\fB, png_bytep \fP\fIptr\fP\fB, png_size_t \fIlength\fP\fB);\fP
-
-\fI\fB
-
-\fI\fB
-
-\fBint png_check_cHRM_fixed (png_structp \fP\fIpng_ptr\fP\fB, png_fixed_point \fP\fIint_white_x\fP\fB, png_fixed_point \fP\fIint_white_y\fP\fB, png_fixed_point \fP\fIint_red_x\fP\fB, png_fixed_point \fP\fIint_red_y\fP\fB, png_fixed_point \fP\fIint_green_x\fP\fB, png_fixed_point \fP\fIint_green_y\fP\fB, png_fixed_point \fP\fIint_blue_x\fP\fB, png_fixed_point \fIint_blue_y\fP\fB);\fP
-
-\fI\fB
-
-\fI\fB
-
-\fBvoid png_check_chunk_name (png_structp \fP\fIpng_ptr\fP\fB, png_bytep \fIchunk_name\fP\fB);\fP
-
-\fI\fB
-
-\fI\fB
-
-\fBint png_check_fp_number (png_charp \fP\fIstring\fP\fB, png_size_t \fP\fIsize\fP\fB, int* \fP\fIstatep\fP\fB, png_size_tp \fIwhereami\fP\fB);\fP
-
-\fI\fB
-
-\fI\fB
-
-\fI\fB
-
-\fI\fB
-
-\fI\fB
-
-\fBint png_check_fp_string (png_charp \fP\fIstring\fP\fB, png_size_t \fIsize\fP\fB);\fP
-
-\fI\fB
-
-\fI\fB
-
-\fI\fB
-
-\fI\fB
-
-\fI\fB
-
-\fBpng_size_t png_check_keyword (png_structp \fP\fIpng_ptr\fP\fB, png_charp \fP\fIkey\fP\fB, png_charpp \fInew_key\fP\fB);\fP
-
-\fI\fB
-
-\fI\fB
-
-\fBvoid png_check_IHDR (png_structp \fP\fIpng_ptr\fP\fB, png_uint_32 \fP\fIwidth\fP\fB, png_uint_32 \fP\fIheight\fP\fB, int \fP\fIbit_depth\fP\fB, int \fP\fIcolor_type\fP\fB, int \fP\fIinterlace_type\fP\fB, int \fP\fIcompression_type\fP\fB, int \fIfilter_type\fP\fB);\fP
-
-\fI\fB
-
-\fI\fB
-
-\fBvoid png_combine_row (png_structp \fP\fIpng_ptr\fP\fB, png_bytep \fP\fIrow\fP\fB, int \fImask\fP\fB);\fP
-
-\fI\fB
-
-\fI\fB
-
-\fBvoid png_correct_palette (png_structp \fP\fIpng_ptr\fP\fB, png_colorp \fP\fIpalette\fP\fB, int \fInum_palette\fP\fB);\fP
-
-\fI\fB
-
-\fI\fB
-
-\fBint png_crc_error (png_structp \fIpng_ptr\fP\fB);\fP
-
-\fI\fB
-
-\fI\fB
-
-\fBint png_crc_finish (png_structp \fP\fIpng_ptr\fP\fB, png_uint_32 \fIskip\fP\fB);\fP
-
-\fI\fB
-
-\fI\fB
-
-\fBvoid png_crc_read (png_structp \fP\fIpng_ptr\fP\fB, png_bytep \fP\fIbuf\fP\fB, png_size_t \fIlength\fP\fB);\fP
-
-\fI\fB
-
-\fI\fB
-
-\fBpng_voidp png_create_struct (int \fItype\fP\fB);\fP
-
-\fI\fB
-
-\fI\fB
-
-\fBpng_voidp png_create_struct_2 (int \fP\fItype\fP\fB, png_malloc_ptr \fP\fImalloc_fn\fP\fB, png_voidp \fImem_ptr\fP\fB);\fP
-
-\fI\fB
-
-\fI\fB
-
-\fBint png_debug(int \fP\fIlevel\fP\fB, png_const_charp \fImessage\fP\fB);\fP
-
-\fI\fB
-
-\fBint png_debug1(int \fP\fIlevel\fP\fB, png_const_charp \fP\fImessage\fP\fB, \fIp1\fP\fB);\fP
-
-\fI\fB
-
-\fBint png_debug2(int \fP\fIlevel\fP\fB, png_const_charp \fP\fImessage\fP\fB, \fP\fIp1\fP\fB, \fIp2\fP\fB);\fP
-
-\fI\fB
-
-\fBvoid png_decompress_chunk (png_structp \fP\fIpng_ptr\fP\fB, int \fP\fIcomp_type\fP\fB, png_size_t \fP\fIchunklength\fP\fB, png_size_t \fP\fIprefix_length\fP\fB, png_size_t \fI*data_length\fP\fB);\fP
-
-\fI\fB
-
-\fI\fB
-
-\fBvoid png_destroy_struct (png_voidp \fIstruct_ptr\fP\fB);\fP
-
-\fI\fB
-
-\fI\fB
-
-\fBvoid png_destroy_struct_2 (png_voidp \fP\fIstruct_ptr\fP\fB, png_free_ptr \fP\fIfree_fn\fP\fB, png_voidp \fImem_ptr\fP\fB);\fP
-
-\fI\fB
-
-\fI\fB
-
-\fBvoid png_do_background (png_row_infop \fP\fIrow_info\fP\fB, png_bytep \fP\fIrow\fP\fB, png_color_16p \fP\fItrans_color\fP\fB, png_color_16p \fP\fIbackground\fP\fB, png_color_16p \fP\fIbackground_1\fP\fB, png_bytep \fP\fIgamma_table\fP\fB, png_bytep \fP\fIgamma_from_1\fP\fB, png_bytep \fP\fIgamma_to_1\fP\fB, png_uint_16pp \fP\fIgamma_16\fP\fB, png_uint_16pp \fP\fIgamma_16_from_1\fP\fB, png_uint_16pp \fP\fIgamma_16_to_1\fP\fB, int \fIgamma_shift\fP\fB);\fP
-
-\fI\fB
-
-\fI\fB
-
-\fBvoid png_do_bgr (png_row_infop \fP\fIrow_info\fP\fB, png_bytep \fIrow\fP\fB);\fP
-
-\fI\fB
-
-\fI\fB
-
-\fBvoid png_do_chop (png_row_infop \fP\fIrow_info\fP\fB, png_bytep \fIrow\fP\fB);\fP
-
-\fI\fB
-
-\fBvoid png_do_expand (png_row_infop \fP\fIrow_info\fP\fB, png_bytep \fP\fIrow\fP\fB, png_color_16p \fItrans_value\fP\fB);\fP
-
-\fI\fB
-
-\fI\fB
-
-\fBvoid png_do_expand_palette (png_row_infop \fP\fIrow_info\fP\fB, png_bytep \fP\fIrow\fP\fB, png_colorp \fP\fIpalette\fP\fB, png_bytep \fP\fItrans\fP\fB, int \fInum_trans\fP\fB);\fP
-
-\fI\fB
-
-\fI\fB
-
-\fBvoid png_do_gamma (png_row_infop \fP\fIrow_info\fP\fB, png_bytep \fP\fIrow\fP\fB, png_bytep \fP\fIgamma_table\fP\fB, png_uint_16pp \fP\fIgamma_16_table\fP\fB, int \fIgamma_shift\fP\fB);\fP
-
-\fI\fB
-
-\fI\fB
-
-\fBvoid png_do_gray_to_rgb (png_row_infop \fP\fIrow_info\fP\fB, png_bytep \fIrow\fP\fB);\fP
-
-\fI\fB
-
-\fI\fB
-
-\fBvoid png_do_invert (png_row_infop \fP\fIrow_info\fP\fB, png_bytep \fIrow\fP\fB);\fP
-
-\fI\fB
-
-\fI\fB
-
-\fBvoid png_do_pack (png_row_infop \fP\fIrow_info\fP\fB, png_bytep \fP\fIrow\fP\fB, png_uint_32 \fIbit_depth\fP\fB);\fP
-
-\fI\fB
-
-\fI\fB
-
-\fBvoid png_do_packswap (png_row_infop \fP\fIrow_info\fP\fB, png_bytep \fIrow\fP\fB);\fP
-
-\fI\fB
-
-\fI\fB
-
-\fBvoid png_do_quantize (png_row_infop \fP\fIrow_info\fP\fB, png_bytep \fP\fIrow\fP\fB, png_bytep \fP\fIpalette_lookup\fP\fB, png_bytep \fIquantize_lookup\fP\fB);\fP
-
-\fI\fB
-
-\fI\fB
-
-\fI\fB
-
-\fBvoid png_do_read_filler (png_row_infop \fP\fIrow_info\fP\fB, png_bytep \fP\fIrow\fP\fB, png_uint_32 \fP\fIfiller\fP\fB, png_uint_32 \fIflags\fP\fB);\fP
-
-\fI\fB
-
-\fI\fB
-
-\fBvoid png_do_read_interlace (png_row_infop \fP\fIrow_info\fP\fB, png_bytep \fP\fIrow\fP\fB, int \fP\fIpass\fP\fB, png_uint_32 \fItransformations\fP\fB);\fP
-
-\fI\fB
-
-\fI\fB
-
-\fBvoid png_do_read_invert_alpha (png_row_infop \fP\fIrow_info\fP\fB, png_bytep \fIrow\fP\fB);\fP
-
-\fI\fB
-
-\fBvoid png_do_read_swap_alpha (png_row_infop \fP\fIrow_info\fP\fB, png_bytep \fIrow\fP\fB);\fP
-
-\fI\fB
-
-\fI\fB
-
-\fBvoid png_do_read_transformations (png_structp \fIpng_ptr\fP\fB);\fP
-
-\fI\fB
-
-\fI\fB
-
-\fBint png_do_rgb_to_gray (png_row_infop \fP\fIrow_info\fP\fB, png_bytep \fIrow\fP\fB);\fP
-
-\fI\fB
-
-\fI\fB
-
-\fBvoid png_do_shift (png_row_infop \fP\fIrow_info\fP\fB, png_bytep \fP\fIrow\fP\fB, png_color_8p \fIbit_depth\fP\fB);\fP
-
-\fI\fB
-
-\fI\fB
-
-\fBvoid png_do_strip_filler (png_row_infop \fP\fIrow_info\fP\fB, png_bytep \fP\fIrow\fP\fB, png_uint_32 \fIflags\fP\fB);\fP
-
-\fI\fB
-
-\fI\fB
-
-\fBvoid png_do_swap (png_row_infop \fP\fIrow_info\fP\fB, png_bytep \fIrow\fP\fB);\fP
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-\fBvoid png_do_unpack (png_row_infop \fP\fIrow_info\fP\fB, png_bytep \fIrow\fP\fB);\fP
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-\fBvoid png_do_unshift (png_row_infop \fP\fIrow_info\fP\fB, png_bytep \fP\fIrow\fP\fB, png_color_8p \fIsig_bits\fP\fB);\fP
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-\fBvoid png_do_write_interlace (png_row_infop \fP\fIrow_info\fP\fB, png_bytep \fP\fIrow\fP\fB, int \fIpass\fP\fB);\fP
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-\fBvoid png_do_write_invert_alpha (png_row_infop \fP\fIrow_info\fP\fB, png_bytep \fIrow\fP\fB);\fP
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-\fBvoid png_do_write_swap_alpha (png_row_infop \fP\fIrow_info\fP\fB, png_bytep \fIrow\fP\fB);\fP
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-\fBvoid png_do_write_transformations (png_structp \fIpng_ptr\fP\fB);\fP
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-\fBvoid *png_far_to_near (png_structp \fP\fIpng_ptr\fP\fB, png_voidp \fP\fIptr\fP\fB, int \fIcheck\fP\fB);\fP
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-\fBvoid png_fixed_error (png_structp \fP\fIpng_ptr\fP\fB, \fIpng_const_charp
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-\fBname, double \fIvalue\fP\fB);\fP
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-\fBvoid png_flush (png_structp \fIpng_ptr\fP\fB);\fP
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-\fBint png_gamma_significant (png_fixed_point \fIgamma\fP\fB);\fP
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-\fBpng_uint_16 png_gamma_16bit_correct (png_structp \fP\fIpng_ptr\fP\fB, unsigned \fP\fIvalue\fP\fB, png_fixed_point \fIgamma\fP\fB);\fP
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-\fBpng_byte png_gamma_8bit_correct (png_structp \fP\fIpng_ptr\fP\fB, unsigned \fP\fIvalue\fP\fB, png_fixed_point \fIgamma\fP\fB);\fP
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-\fBvoid png_handle_bKGD (png_structp \fP\fIpng_ptr\fP\fB, png_infop \fP\fIinfo_ptr\fP\fB, png_uint_32 \fIlength\fP\fB);\fP
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-\fBvoid png_handle_cHRM (png_structp \fP\fIpng_ptr\fP\fB, png_infop \fP\fIinfo_ptr\fP\fB, png_uint_32 \fIlength\fP\fB);\fP
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-\fI\fB
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-\fBvoid png_handle_gAMA (png_structp \fP\fIpng_ptr\fP\fB, png_infop \fP\fIinfo_ptr\fP\fB, png_uint_32 \fIlength\fP\fB);\fP
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-\fI\fB
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-\fBvoid png_handle_hIST (png_structp \fP\fIpng_ptr\fP\fB, png_infop \fP\fIinfo_ptr\fP\fB, png_uint_32 \fIlength\fP\fB);\fP
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-\fI\fB
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-\fI\fB
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-\fBvoid png_handle_IEND (png_structp \fP\fIpng_ptr\fP\fB, png_infop \fP\fIinfo_ptr\fP\fB, png_uint_32 \fIlength\fP\fB);\fP
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-\fI\fB
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-\fI\fB
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-\fBvoid png_handle_IHDR (png_structp \fP\fIpng_ptr\fP\fB, png_infop \fP\fIinfo_ptr\fP\fB, png_uint_32 \fIlength\fP\fB);\fP
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-\fI\fB
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-\fI\fB
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-\fBvoid png_handle_iCCP (png_structp \fP\fIpng_ptr\fP\fB, png_infop \fP\fIinfo_ptr\fP\fB, png_uint_32 \fIlength\fP\fB);\fP
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-\fI\fB
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-\fI\fB
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-\fBvoid png_handle_iTXt (png_structp \fP\fIpng_ptr\fP\fB, png_infop \fP\fIinfo_ptr\fP\fB, png_uint_32 \fIlength\fP\fB);\fP
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-\fBvoid png_handle_oFFs (png_structp \fP\fIpng_ptr\fP\fB, png_infop \fP\fIinfo_ptr\fP\fB, png_uint_32 \fIlength\fP\fB);\fP
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-\fI\fB
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-\fBvoid png_handle_pCAL (png_structp \fP\fIpng_ptr\fP\fB, png_infop \fP\fIinfo_ptr\fP\fB, png_uint_32 \fIlength\fP\fB);\fP
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-\fI\fB
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-\fBvoid png_handle_pHYs (png_structp \fP\fIpng_ptr\fP\fB, png_infop \fP\fIinfo_ptr\fP\fB, png_uint_32 \fIlength\fP\fB);\fP
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-\fBvoid png_handle_PLTE (png_structp \fP\fIpng_ptr\fP\fB, png_infop \fP\fIinfo_ptr\fP\fB, png_uint_32 \fIlength\fP\fB);\fP
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-\fI\fB
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-\fBvoid png_handle_sBIT (png_structp \fP\fIpng_ptr\fP\fB, png_infop \fP\fIinfo_ptr\fP\fB, png_uint_32 \fIlength\fP\fB);\fP
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-\fI\fB
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-\fBvoid png_handle_sCAL (png_structp \fP\fIpng_ptr\fP\fB, png_infop \fP\fIinfo_ptr\fP\fB, png_uint_32 \fIlength\fP\fB);\fP
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-\fI\fB
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-\fI\fB
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-\fBvoid png_handle_sPLT (png_structp \fP\fIpng_ptr\fP\fB, png_infop \fP\fIinfo_ptr\fP\fB, png_uint_32 \fIlength\fP\fB);\fP
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-\fI\fB
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-\fI\fB
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-\fBvoid png_handle_sRGB (png_structp \fP\fIpng_ptr\fP\fB, png_infop \fP\fIinfo_ptr\fP\fB, png_uint_32 \fIlength\fP\fB);\fP
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-\fI\fB
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-\fI\fB
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-\fBvoid png_handle_tEXt (png_structp \fP\fIpng_ptr\fP\fB, png_infop \fP\fIinfo_ptr\fP\fB, png_uint_32 \fIlength\fP\fB);\fP
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-\fI\fB
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-\fI\fB
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-\fBvoid png_handle_tIME (png_structp \fP\fIpng_ptr\fP\fB, png_infop \fP\fIinfo_ptr\fP\fB, png_uint_32 \fIlength\fP\fB);\fP
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-\fI\fB
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-\fI\fB
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-\fBvoid png_handle_tRNS (png_structp \fP\fIpng_ptr\fP\fB, png_infop \fP\fIinfo_ptr\fP\fB, png_uint_32 \fIlength\fP\fB);\fP
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-\fI\fB
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-\fI\fB
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-\fBvoid png_handle_unknown (png_structp \fP\fIpng_ptr\fP\fB, png_infop \fP\fIinfo_ptr\fP\fB, png_uint_32 \fIlength\fP\fB);\fP
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-\fI\fB
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-\fI\fB
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-\fBvoid png_handle_zTXt (png_structp \fP\fIpng_ptr\fP\fB, png_infop \fP\fIinfo_ptr\fP\fB, png_uint_32 \fIlength\fP\fB);\fP
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-\fI\fB
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-\fBvoid png_info_destroy (png_structp \fP\fIpng_ptr\fP\fB, png_infop \fIinfo_ptr\fP\fB);\fP
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-\fI\fB
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-\fBvoid png_init_mmx_flags (png_structp \fIpng_ptr\fP\fB);\fP
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-\fI\fB
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-\fBvoid png_init_read_transformations (png_structp \fIpng_ptr\fP\fB);\fP
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-\fI\fB
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-\fBint png_muldiv (png_fixed_point_p \fP\fIres\fP\fB, png_fixed_point \fP\fIa\fP\fB, png_int_32 \fP\fItimes\fP\fB, png_int_32 \fIdiv\fP\fB);\fP
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-\fI\fB
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-\fI\fB
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-\fI\fB
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-\fBpng_fixed_point png_muldiv_warn (png_structp \fP\fIpng_ptr\fP\fB, png_fixed_point \fP\fIa\fP\fB, png_int_32 \fP\fItimes\fP\fB, png_int_32 \fIdiv\fP\fB);\fP
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-\fI\fB
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-\fBvoid png_process_IDAT_data (png_structp \fP\fIpng_ptr\fP\fB, png_bytep \fP\fIbuffer\fP\fB, png_size_t \fIbuffer_length\fP\fB);\fP
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-\fI\fB
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-\fI\fB
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-\fBvoid png_process_some_data (png_structp \fP\fIpng_ptr\fP\fB, png_infop \fIinfo_ptr\fP\fB);\fP
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-\fI\fB
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-\fBvoid png_push_check_crc (png_structp \fIpng_ptr\fP\fB);\fP
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-\fI\fB
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-\fBvoid png_push_crc_finish (png_structp \fIpng_ptr\fP\fB);\fP
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-\fI\fB
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-\fBvoid png_push_crc_skip (png_structp \fP\fIpng_ptr\fP\fB, png_uint_32 \fIlength\fP\fB);\fP
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-\fI\fB
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-\fI\fB
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-\fBvoid png_push_fill_buffer (png_structp \fP\fIpng_ptr\fP\fB, png_bytep \fP\fIbuffer\fP\fB, png_size_t \fIlength\fP\fB);\fP
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-\fI\fB
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-\fI\fB
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-\fBvoid png_push_handle_tEXt (png_structp \fP\fIpng_ptr\fP\fB, png_infop \fP\fIinfo_ptr\fP\fB, png_uint_32 \fIlength\fP\fB);\fP
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-\fI\fB
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-\fI\fB
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-\fBvoid png_push_handle_unknown (png_structp \fP\fIpng_ptr\fP\fB, png_infop \fP\fIinfo_ptr\fP\fB, png_uint_32 \fIlength\fP\fB);\fP
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-\fI\fB
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-\fI\fB
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-\fBvoid png_push_handle_zTXt (png_structp \fP\fIpng_ptr\fP\fB, png_infop \fP\fIinfo_ptr\fP\fB, png_uint_32 \fIlength\fP\fB);\fP
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-\fI\fB
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-\fI\fB
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-\fBvoid png_push_have_end (png_structp \fP\fIpng_ptr\fP\fB, png_infop \fIinfo_ptr\fP\fB);\fP
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-\fI\fB
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-\fI\fB
-
-\fBvoid png_push_have_info (png_structp \fP\fIpng_ptr\fP\fB, png_infop \fIinfo_ptr\fP\fB);\fP
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-\fI\fB
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-\fI\fB
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-\fBvoid png_push_have_row (png_structp \fP\fIpng_ptr\fP\fB, png_bytep \fIrow\fP\fB);\fP
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-\fI\fB
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-\fI\fB
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-\fBvoid png_push_process_row (png_structp \fIpng_ptr\fP\fB);\fP
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-\fI\fB
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-\fBvoid png_push_read_chunk (png_structp \fP\fIpng_ptr\fP\fB, png_infop \fIinfo_ptr\fP\fB);\fP
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-\fI\fB
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-\fI\fB
-
-\fBvoid png_push_read_end (png_structp \fP\fIpng_ptr\fP\fB, png_infop \fIinfo_ptr\fP\fB);\fP
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-\fI\fB
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-\fI\fB
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-\fBvoid png_push_read_IDAT (png_structp \fIpng_ptr\fP\fB);\fP
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-\fI\fB
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-\fBvoid png_push_read_sig (png_structp \fP\fIpng_ptr\fP\fB, png_infop \fIinfo_ptr\fP\fB);\fP
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-\fI\fB
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-\fI\fB
-
-\fBvoid png_push_read_tEXt (png_structp \fP\fIpng_ptr\fP\fB, png_infop \fIinfo_ptr\fP\fB);\fP
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-\fI\fB
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-\fI\fB
-
-\fBvoid png_push_read_zTXt (png_structp \fP\fIpng_ptr\fP\fB, png_infop \fIinfo_ptr\fP\fB);\fP
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-\fI\fB
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-\fI\fB
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-\fBvoid png_push_restore_buffer (png_structp \fP\fIpng_ptr\fP\fB, png_bytep \fP\fIbuffer\fP\fB, png_size_t \fIbuffer_length\fP\fB);\fP
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-\fI\fB
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-\fBvoid png_push_save_buffer (png_structp \fIpng_ptr\fP\fB);\fP
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-\fI\fB
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-\fBvoid png_read_data (png_structp \fP\fIpng_ptr\fP\fB, png_bytep \fP\fIdata\fP\fB, png_size_t \fIlength\fP\fB);\fP
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-\fI\fB
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-\fBvoid png_read_destroy (png_structp \fP\fIpng_ptr\fP\fB, png_infop \fP\fIinfo_ptr\fP\fB, png_infop \fIend_info_ptr\fP\fB);\fP
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-\fI\fB
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-\fBvoid png_read_filter_row (png_structp \fP\fIpng_ptr\fP\fB, png_row_infop \fP\fIrow_info\fP\fB, png_bytep \fP\fIrow\fP\fB, png_bytep \fP\fIprev_row\fP\fB, int \fIfilter\fP\fB);\fP
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-\fI\fB
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-\fI\fB
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-\fBvoid png_read_finish_row (png_structp \fIpng_ptr\fP\fB);\fP
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-\fI\fB
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-\fBvoid png_read_push_finish_row (png_structp \fIpng_ptr\fP\fB);\fP
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-\fI\fB
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-\fBvoid png_read_start_row (png_structp \fIpng_ptr\fP\fB);\fP
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-\fI\fB
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-\fBvoid png_read_sig (png_structp \fP\fIpng_ptr\fP\fB, png_infop \fIinfo_ptr\fP\fB);\fP
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-\fI\fB
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-\fBvoid png_read_transform_info (png_structp \fP\fIpng_ptr\fP\fB, png_infop \fIinfo_ptr\fP\fB);\fP
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-\fI\fB
-
-\fBpng_fixed_point png_reciprocal (png_fixed_point \fIa\fP\fB);\fP
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-\fI\fB
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-\fBpng_fixed_point png_reciprocal2 (png_fixed_point \fP\fIa\fP\fB, png_fixed_point \fIb\fP\fB);\fP
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-\fI\fB
-
-\fBvoid png_reset_crc (png_structp \fIpng_ptr\fP\fB);\fP
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-\fI\fB
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-\fBint png_set_text_2 (png_structp \fP\fIpng_ptr\fP\fB, png_infop \fP\fIinfo_ptr\fP\fB, png_textp \fP\fItext_ptr\fP\fB, int \fInum_text\fP\fB);\fP
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-\fI\fB
-
-\fBvoid png_write_cHRM (png_structp \fP\fIpng_ptr\fP\fB, double \fP\fIwhite_x\fP\fB, double \fP\fIwhite_y\fP\fB, double \fP\fIred_x\fP\fB, double \fP\fIred_y\fP\fB, double \fP\fIgreen_x\fP\fB, double \fP\fIgreen_y\fP\fB, double \fP\fIblue_x\fP\fB, double \fIblue_y\fP\fB);\fP
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-\fI\fB
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-\fI\fB
-
-\fBvoid png_write_cHRM_fixed (png_structp \fP\fIpng_ptr\fP\fB, png_uint_32 \fP\fIwhite_x\fP\fB, png_uint_32 \fP\fIwhite_y\fP\fB, png_uint_32 \fP\fIred_x\fP\fB, png_uint_32 \fP\fIred_y\fP\fB, png_uint_32 \fP\fIgreen_x\fP\fB, png_uint_32 \fP\fIgreen_y\fP\fB, png_uint_32 \fP\fIblue_x\fP\fB, png_uint_32 \fIblue_y\fP\fB);\fP
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-\fI\fB
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-\fI\fB
-
-\fBvoid png_write_data (png_structp \fP\fIpng_ptr\fP\fB, png_bytep \fP\fIdata\fP\fB, png_size_t \fIlength\fP\fB);\fP
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-\fI\fB
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-\fBvoid png_write_destroy (png_structp \fIpng_ptr\fP\fB);\fP
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-\fI\fB
-
-\fBvoid png_write_filtered_row (png_structp \fP\fIpng_ptr\fP\fB, png_bytep \fIfiltered_row\fP\fB);\fP
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-\fI\fB
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-\fI\fB
-
-\fBvoid png_write_find_filter (png_structp \fP\fIpng_ptr\fP\fB, png_row_infop \fIrow_info\fP\fB);\fP
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-\fI\fB
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-\fI\fB
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-\fBvoid png_write_finish_row (png_structp \fIpng_ptr\fP\fB);\fP
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-\fI\fB
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-\fI\fB
-
-\fBvoid png_write_gAMA (png_structp \fP\fIpng_ptr\fP\fB, double \fIfile_gamma\fP\fB);\fP
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-\fI\fB
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-\fI\fB
-
-\fBvoid png_write_gAMA_fixed (png_structp \fP\fIpng_ptr\fP\fB, png_uint_32 \fIint_file_gamma\fP\fB);\fP
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-\fI\fB
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-\fI\fB
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-\fBvoid png_write_hIST (png_structp \fP\fIpng_ptr\fP\fB, png_uint_16p \fP\fIhist\fP\fB, int \fInum_hist\fP\fB);\fP
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-\fI\fB
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-\fI\fB
-
-\fBvoid png_write_iCCP (png_structp \fP\fIpng_ptr\fP\fB, png_charp \fP\fIname\fP\fB, int \fP\fIcompression_type\fP\fB, png_charp \fP\fIprofile\fP\fB, int \fIproflen\fP\fB);\fP
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-\fI\fB
-
-\fI\fB
-
-\fBvoid png_write_IDAT (png_structp \fP\fIpng_ptr\fP\fB, png_bytep \fP\fIdata\fP\fB, png_size_t \fIlength\fP\fB);\fP
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-\fI\fB
-
-\fI\fB
-
-\fBvoid png_write_IEND (png_structp \fIpng_ptr\fP\fB);\fP
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-\fI\fB
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-\fI\fB
-
-\fBvoid png_write_IHDR (png_structp \fP\fIpng_ptr\fP\fB, png_uint_32 \fP\fIwidth\fP\fB, png_uint_32 \fP\fIheight\fP\fB, int \fP\fIbit_depth\fP\fB, int \fP\fIcolor_type\fP\fB, int \fP\fIcompression_type\fP\fB, int \fP\fIfilter_type\fP\fB, int \fIinterlace_type\fP\fB);\fP
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-\fI\fB
-
-\fI\fB
-
-\fBvoid png_write_iTXt (png_structp \fP\fIpng_ptr\fP\fB, int \fP\fIcompression\fP\fB, png_charp \fP\fIkey\fP\fB, png_charp \fP\fIlang\fP\fB, png_charp \fP\fItranslated_key\fP\fB, png_charp \fItext\fP\fB);\fP
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-\fI\fB
-
-\fI\fB
-
-\fBvoid png_write_oFFs (png_structp \fP\fIpng_ptr\fP\fB, png_uint_32 \fP\fIx_offset\fP\fB, png_uint_32 \fP\fIy_offset\fP\fB, int \fIunit_type\fP\fB);\fP
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-\fI\fB
-
-\fI\fB
-
-\fBvoid png_write_pCAL (png_structp \fP\fIpng_ptr\fP\fB, png_charp \fP\fIpurpose\fP\fB, png_int_32 \fP\fIX0\fP\fB, png_int_32 \fP\fIX1\fP\fB, int \fP\fItype\fP\fB, int \fP\fInparams\fP\fB, png_charp \fP\fIunits\fP\fB, png_charpp \fIparams\fP\fB);\fP
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-\fI\fB
-
-\fI\fB
-
-\fBvoid png_write_pHYs (png_structp \fP\fIpng_ptr\fP\fB, png_uint_32 \fP\fIx_pixels_per_unit\fP\fB, png_uint_32 \fP\fIy_pixels_per_unit\fP\fB, int \fIunit_type\fP\fB);\fP
-
-\fI\fB
-
-\fI\fB
-
-\fBvoid png_write_PLTE (png_structp \fP\fIpng_ptr\fP\fB, png_colorp \fP\fIpalette\fP\fB, png_uint_32 \fInum_pal\fP\fB);\fP
-
-\fI\fB
-
-\fI\fB
-
-\fBvoid png_write_sBIT (png_structp \fP\fIpng_ptr\fP\fB, png_color_8p \fP\fIsbit\fP\fB, int \fIcolor_type\fP\fB);\fP
-
-\fI\fB
-
-\fI\fB
-
-\fBvoid png_write_sCAL (png_structp \fP\fIpng_ptr\fP\fB, png_charp \fP\fIunit\fP\fB, double \fP\fIwidth\fP\fB, double \fIheight\fP\fB);\fP
-
-\fI\fB
-
-\fI\fB
-
-\fBvoid png_write_sCAL_s (png_structp \fP\fIpng_ptr\fP\fB, png_charp \fP\fIunit\fP\fB, png_charp \fP\fIwidth\fP\fB, png_charp \fIheight\fP\fB);\fP
-
-\fI\fB
-
-\fI\fB
-
-\fBvoid png_write_sRGB (png_structp \fP\fIpng_ptr\fP\fB, int \fIintent\fP\fB);\fP
-
-\fI\fB
-
-\fI\fB
-
-\fBvoid png_write_sPLT (png_structp \fP\fIpng_ptr\fP\fB, png_spalette_p \fIpalette\fP\fB);\fP
-
-\fI\fB
-
-\fI\fB
-
-\fBvoid png_write_start_row (png_structp \fIpng_ptr\fP\fB);\fP
-
-\fI\fB
-
-\fI\fB
-
-\fBvoid png_write_tEXt (png_structp \fP\fIpng_ptr\fP\fB, png_charp \fP\fIkey\fP\fB, png_charp \fP\fItext\fP\fB, png_size_t \fItext_len\fP\fB);\fP
-
-\fI\fB
-
-\fI\fB
-
-\fBvoid png_write_tIME (png_structp \fP\fIpng_ptr\fP\fB, png_timep \fImod_time\fP\fB);\fP
-
-\fI\fB
-
-\fI\fB
-
-\fBvoid png_write_tRNS (png_structp \fP\fIpng_ptr\fP\fB, png_bytep \fP\fItrans\fP\fB, png_color_16p \fP\fIvalues\fP\fB, int \fP\fInumber\fP\fB, int \fIcolor_type\fP\fB);\fP
-
-\fI\fB
-
-\fI\fB
-
-\fBvoid png_write_zTXt (png_structp \fP\fIpng_ptr\fP\fB, png_charp \fP\fIkey\fP\fB, png_charp \fP\fItext\fP\fB, png_size_t \fP\fItext_len\fP\fB, int \fIcompression\fP\fB);\fP
-
-\fI\fB
-
-\fI\fB
-
-\fBvoidpf png_zalloc (voidpf \fP\fIpng_ptr\fP\fB, uInt \fP\fIitems\fP\fB, uInt \fIsize\fP\fB);\fP
-
-\fI\fB
-
-\fI\fB
-
-\fBvoid png_zfree (voidpf \fP\fIpng_ptr\fP\fB, voidpf \fIptr\fP\fB);\fP
-
-\fI\fB
-
-\fBvoid png_fixed_error (png_structp \fP\fIpng_ptr\fP\fB, png_const_charp \fP\fIname\fP\fB, double \fIvalue\fP\fB);\fP
+\fBof each \fIfunction.

 \fI\fB

 .SH DESCRIPTION
-The functions listed above are used privately by libpng
+The functions previously listed here are  used privately by libpng
 and are not recommended for use by applications.  They are
 not "exported" to applications using shared libraries.  They
 are listed alphabetically here as an aid to libpng maintainers.
--- a/ltmain.sh
+++ b/ltmain.sh
--- a/png.5
+++ b/png.5
@@ -1,4 +1,4 @@
-.TH PNG 5 "November 21, 2010"
+.TH PNG 5 "March 19, 2011"
 .SH NAME
 png \- Portable Network Graphics (PNG) format
 .SH DESCRIPTION
--- a/png.c
+++ b/png.c
@@ -1,8 +1,8 @@

 /* png.c - location for general purpose libpng functions
 *
- * Last changed in libpng 1.5.0 [(PENDING RELEASE)]
- * Copyright (c) 1998-2010 Glenn Randers-Pehrson
+ * Last changed in libpng 1.5.1 [February 3, 2011]
+ * Copyright (c) 1998-2011 Glenn Randers-Pehrson
 * (Version 0.96 Copyright (c) 1996, 1997 Andreas Dilger)
 * (Version 0.88 Copyright (c) 1995, 1996 Guy Eric Schalnat, Group 42, Inc.)
 *
@@ -14,7 +14,7 @@
 #include "pngpriv.h"

 /* Generate a compiler error if there is an old png.h in the search path. */
-typedef png_libpng_version_1_5_0beta55 Your_png_h_is_not_version_1_5_0beta55;
+typedef png_libpng_version_1_5_2rc01 Your_png_h_is_not_version_1_5_2rc01;

 /* Tells libpng that we have already handled the first "num_bytes" bytes
 * of the PNG file signature.  If the PNG data is embedded into another
@@ -441,11 +441,10 @@ png_free_data(png_structp png_ptr, png_infop info_ptr, png_uint_32 mask,
   }
 #endif

-   if (num == -1)
-      info_ptr->free_me &= ~mask;
+   if (num != -1)
+      mask &= ~PNG_FREE_MUL;

-   else
-      info_ptr->free_me &= ~(mask & ~PNG_FREE_MUL);
+   info_ptr->free_me &= ~mask;
 }

 /* This is an internal routine to free any memory that the info struct is
@@ -548,22 +547,22 @@ png_convert_to_rfc1123(png_structp png_ptr, png_const_timep ptime)
 #endif /* defined(PNG_READ_SUPPORTED) || defined(PNG_WRITE_SUPPORTED) */

 png_const_charp PNGAPI
-png_get_copyright(png_structp png_ptr)
+png_get_copyright(png_const_structp png_ptr)
 {
-   png_ptr = png_ptr;  /* Silence compiler warning about unused png_ptr */
+   PNG_UNUSED(png_ptr)  /* Silence compiler warning about unused png_ptr */
 #ifdef PNG_STRING_COPYRIGHT
-      return PNG_STRING_COPYRIGHT
+   return PNG_STRING_COPYRIGHT
 #else
 #  ifdef __STDC__
   return PNG_STRING_NEWLINE \
-     "libpng version 1.5.0beta55 - November 21, 2010" PNG_STRING_NEWLINE \
-     "Copyright (c) 1998-2010 Glenn Randers-Pehrson" PNG_STRING_NEWLINE \
+     "libpng version 1.5.2rc01 - March 19, 2011" PNG_STRING_NEWLINE \
+     "Copyright (c) 1998-2011 Glenn Randers-Pehrson" PNG_STRING_NEWLINE \
     "Copyright (c) 1996-1997 Andreas Dilger" PNG_STRING_NEWLINE \
     "Copyright (c) 1995-1996 Guy Eric Schalnat, Group 42, Inc." \
     PNG_STRING_NEWLINE;
 #  else
-      return "libpng version 1.5.0beta55 - November 21, 2010\
-      Copyright (c) 1998-2010 Glenn Randers-Pehrson\
+      return "libpng version 1.5.2rc01 - March 19, 2011\
+      Copyright (c) 1998-2011 Glenn Randers-Pehrson\
      Copyright (c) 1996-1997 Andreas Dilger\
      Copyright (c) 1995-1996 Guy Eric Schalnat, Group 42, Inc.";
 #  endif
@@ -579,25 +578,25 @@ png_get_copyright(png_structp png_ptr)
 * it is guaranteed that png.c uses the correct version of png.h.
 */
 png_const_charp PNGAPI
-png_get_libpng_ver(png_structp png_ptr)
+png_get_libpng_ver(png_const_structp png_ptr)
 {
   /* Version of *.c files used when building libpng */
   return png_get_header_ver(png_ptr);
 }

 png_const_charp PNGAPI
-png_get_header_ver(png_structp png_ptr)
+png_get_header_ver(png_const_structp png_ptr)
 {
   /* Version of *.h files used when building libpng */
-   png_ptr = png_ptr;  /* Silence compiler warning about unused png_ptr */
+   PNG_UNUSED(png_ptr)  /* Silence compiler warning about unused png_ptr */
   return PNG_LIBPNG_VER_STRING;
 }

 png_const_charp PNGAPI
-png_get_header_version(png_structp png_ptr)
+png_get_header_version(png_const_structp png_ptr)
 {
   /* Returns longer string containing both version and date */
-   png_ptr = png_ptr;  /* Silence compiler warning about unused png_ptr */
+   PNG_UNUSED(png_ptr)  /* Silence compiler warning about unused png_ptr */
 #ifdef __STDC__
   return PNG_HEADER_VERSION_STRING
 #  ifndef PNG_READ_SUPPORTED
@@ -1032,10 +1031,10 @@ int
 png_check_fp_string(png_const_charp string, png_size_t size)
 {
   int        state=0;
-   png_size_t index=0;
+   png_size_t char_index=0;

-   return png_check_fp_number(string, size, &state, &index) &&
-      (index == size || string[index] == 0);
+   return png_check_fp_number(string, size, &state, &char_index) &&
+      (char_index == size || string[char_index] == 0);
 }
 #endif /* pCAL or sCAL */

@@ -1109,46 +1108,46 @@ png_ascii_from_fp(png_structp png_ptr, png_charp ascii, png_size_t size,

      if (fp >= DBL_MIN && fp <= DBL_MAX)
      {
-         int exp;       /* A base 10 exponent */
-         double base;   /* 10^exp */
+         int exp_b10;       /* A base 10 exponent */
+         double base;   /* 10^exp_b10 */

         /* First extract a base 10 exponent of the number,
          * the calculation below rounds down when converting
          * from base 2 to base 10 (multiply by log10(2) -
-          * 0.3010, but 77/256 is 0.3008, so exp needs to
+          * 0.3010, but 77/256 is 0.3008, so exp_b10 needs to
          * be increased.  Note that the arithmetic shift
          * performs a floor() unlike C arithmetic - using a
          * C multiply would break the following for negative
          * exponents.
          */
-         (void)frexp(fp, &exp); /* exponent to base 2 */
+         (void)frexp(fp, &exp_b10); /* exponent to base 2 */

-         exp = (exp * 77) >> 8; /* <= exponent to base 10 */
+         exp_b10 = (exp_b10 * 77) >> 8; /* <= exponent to base 10 */

         /* Avoid underflow here. */
-         base = png_pow10(exp); /* May underflow */
+         base = png_pow10(exp_b10); /* May underflow */

         while (base < DBL_MIN || base < fp)
         {
            /* And this may overflow. */
-            double test = png_pow10(exp+1);
+            double test = png_pow10(exp_b10+1);

            if (test <= DBL_MAX)
-               ++exp, base = test;
+               ++exp_b10, base = test;

            else
               break;
         }

-         /* Normalize fp and correct exp, after this fp is in the
-          * range [.1,1) and exp is both the exponent and the digit
+         /* Normalize fp and correct exp_b10, after this fp is in the
+          * range [.1,1) and exp_b10 is both the exponent and the digit
          * *before* which the decimal point should be inserted
          * (starting with 0 for the first digit).  Note that this
-          * works even if 10^exp is out of range because of the
+          * works even if 10^exp_b10 is out of range because of the
          * test on DBL_MAX above.
          */
         fp /= base;
-         while (fp >= 1) fp /= 10, ++exp;
+         while (fp >= 1) fp /= 10, ++exp_b10;

         /* Because of the code above fp may, at this point, be
          * less than .1, this is ok because the code below can
@@ -1163,10 +1162,10 @@ png_ascii_from_fp(png_structp png_ptr, png_charp ascii, png_size_t size,
            /* Allow up to two leading zeros - this will not lengthen
             * the number compared to using E-n.
             */
-            if (exp < 0 && exp > -3) /* PLUS 3 TOTAL 4 */
+            if (exp_b10 < 0 && exp_b10 > -3) /* PLUS 3 TOTAL 4 */
            {
-               czero = -exp; /* PLUS 2 digits: TOTAL 3 */
-               exp = 0;      /* Dot added below before first output. */
+               czero = -exp_b10; /* PLUS 2 digits: TOTAL 3 */
+               exp_b10 = 0;      /* Dot added below before first output. */
            }
            else
               czero = 0;    /* No zeros to add */
@@ -1208,17 +1207,17 @@ png_ascii_from_fp(png_structp png_ptr, png_charp ascii, png_size_t size,
                        {
                           int ch = *--ascii;

-                           if (exp != (-1))
-                              ++exp;
+                           if (exp_b10 != (-1))
+                              ++exp_b10;

                           else if (ch == 46)
                           {
                              ch = *--ascii, ++size;
-                              /* Advance exp to '1', so that the
+                              /* Advance exp_b10 to '1', so that the
                               * decimal point happens after the
                               * previous digit.
                               */
-                              exp = 1;
+                              exp_b10 = 1;
                           }

                           --cdigits;
@@ -1231,7 +1230,7 @@ png_ascii_from_fp(png_structp png_ptr, png_charp ascii, png_size_t size,
                         */
                        if (d > 9)  /* cdigits == 0 */
                        {
-                           if (exp == (-1))
+                           if (exp_b10 == (-1))
                           {
                              /* Leading decimal point (plus zeros?), if
                               * we lose the decimal point here it must
@@ -1240,14 +1239,14 @@ png_ascii_from_fp(png_structp png_ptr, png_charp ascii, png_size_t size,
                              int ch = *--ascii;

                              if (ch == 46)
-                                 ++size, exp = 1;
+                                 ++size, exp_b10 = 1;

-                              /* Else lost a leading zero, so 'exp' is
+                              /* Else lost a leading zero, so 'exp_b10' is
                               * still ok at (-1)
                               */
                           }
                           else
-                              ++exp;
+                              ++exp_b10;

                           /* In all cases we output a '1' */
                           d = 1;
@@ -1270,23 +1269,24 @@ png_ascii_from_fp(png_structp png_ptr, png_charp ascii, png_size_t size,

                  while (czero > 0)
                  {
-                     /* exp == (-1) means we just output the decimal
-                      * place - after the DP don't adjust 'exp' any
+                     /* exp_b10 == (-1) means we just output the decimal
+                      * place - after the DP don't adjust 'exp_b10' any
                      * more!
                      */
-                     if (exp != (-1))
+                     if (exp_b10 != (-1))
                     {
-                        if (exp == 0) *ascii++ = 46, --size;
+                        if (exp_b10 == 0) *ascii++ = 46, --size;
                        /* PLUS 1: TOTAL 4 */
-                        --exp;
+                        --exp_b10;
                     }
                     *ascii++ = 48, --czero;
                  }

-                  if (exp != (-1))
+                  if (exp_b10 != (-1))
                  {
-                     if (exp == 0) *ascii++ = 46, --size; /* counted above */
-                     --exp;
+                     if (exp_b10 == 0) *ascii++ = 46, --size; /* counted
+                                                                 above */
+                     --exp_b10;
                  }
                  *ascii++ = (char)(48 + (int)d), ++cdigits;
               }
@@ -1297,12 +1297,12 @@ png_ascii_from_fp(png_structp png_ptr, png_charp ascii, png_size_t size,

            /* Check for an exponent, if we don't need one we are
             * done and just need to terminate the string.  At
-             * this point exp==(-1) is effectively if flag - it got
+             * this point exp_b10==(-1) is effectively if flag - it got
             * to '-1' because of the decrement after outputing
             * the decimal point above (the exponent required is
             * *not* -1!)
             */
-            if (exp >= (-1) && exp <= 2)
+            if (exp_b10 >= (-1) && exp_b10 <= 2)
            {
               /* The following only happens if we didn't output the
                * leading zeros above for negative exponent, so this
@@ -1311,7 +1311,7 @@ png_ascii_from_fp(png_structp png_ptr, png_charp ascii, png_size_t size,
                * zeros were *not* output, so this doesn't increase
                * the output count.
                */
-               while (--exp >= 0) *ascii++ = 48;
+               while (--exp_b10 >= 0) *ascii++ = 48;

               *ascii = 0;

@@ -1330,18 +1330,18 @@ png_ascii_from_fp(png_structp png_ptr, png_charp ascii, png_size_t size,
            size -= cdigits;

            *ascii++ = 69, --size;    /* 'E': PLUS 1 TOTAL 2+precision*/
-            if (exp < 0)
+            if (exp_b10 < 0)
            {
               *ascii++ = 45, --size; /* '-': PLUS 1 TOTAL 3+precision */
-               exp = -exp;
+               exp_b10 = -exp_b10;
            }

            cdigits = 0;

-            while (exp > 0)
+            while (exp_b10 > 0)
            {
-               exponent[cdigits++] = (char)(48 + exp % 10);
-               exp /= 10;
+               exponent[cdigits++] = (char)(48 + exp_b10 % 10);
+               exp_b10 /= 10;
            }

            /* Need another size check here for the exponent digits, so
@@ -1460,11 +1460,10 @@ png_fixed(png_structp png_ptr, double fp, png_const_charp text)
 {
   double r = floor(100000 * fp + .5);

-   if (r <= 2147483647. && r >= -2147483648.)
-      return (png_fixed_point)r;
+   if (r > 2147483647. || r < -2147483648.)
+      png_fixed_error(png_ptr, text);

-   png_fixed_error(png_ptr, text);
-   /*NOT REACHED*/
+   return (png_fixed_point)r;
 }
 #endif

@@ -1478,10 +1477,10 @@ png_fixed(png_structp png_ptr, double fp, png_const_charp text)
 */
 int
 png_muldiv(png_fixed_point_p res, png_fixed_point a, png_int_32 times,
-    png_int_32 div)
+    png_int_32 divisor)
 {
-   /* Return a * times / div, rounded. */
-   if (div != 0)
+   /* Return a * times / divisor, rounded. */
+   if (divisor != 0)
   {
      if (a == 0 || times == 0)
      {
@@ -1493,7 +1492,7 @@ png_muldiv(png_fixed_point_p res, png_fixed_point a, png_int_32 times,
 #ifdef PNG_FLOATING_ARITHMETIC_SUPPORTED
         double r = a;
         r *= times;
-         r /= div;
+         r /= divisor;
         r = floor(r+.5);

         /* A png_fixed_point is a 32 bit integer. */
@@ -1517,10 +1516,10 @@ png_muldiv(png_fixed_point_p res, png_fixed_point a, png_int_32 times,
         else
            T = times;

-         if (div < 0)
-            negative = !negative, D = -div;
+         if (divisor < 0)
+            negative = !negative, D = -divisor;
         else
-            D = div;
+            D = divisor;

         /* Following can't overflow because the arguments only
          * have 31 bits each, however the result may be 32 bits.
@@ -1597,11 +1596,11 @@ png_muldiv(png_fixed_point_p res, png_fixed_point a, png_int_32 times,
 */
 png_fixed_point
 png_muldiv_warn(png_structp png_ptr, png_fixed_point a, png_int_32 times,
-    png_int_32 div)
+    png_int_32 divisor)
 {
   png_fixed_point result;

-   if (png_muldiv(&result, a, times, div))
+   if (png_muldiv(&result, a, times, divisor))
      return result;

   png_warning(png_ptr, "fixed point overflow ignored");
@@ -1792,7 +1791,7 @@ png_8bit_l2[128] =
 static png_int_32
 png_log8bit(unsigned int x)
 {
-   unsigned int log = 0;
+   unsigned int lg2 = 0;
   /* Each time 'x' is multiplied by 2, 1 must be subtracted off the final log,
    * because the log is actually negate that means adding 1.  The final
    * returned value thus has the range 0 (for 255 input) to 7.994 (for 1
@@ -1803,16 +1802,16 @@ png_log8bit(unsigned int x)
      return 0xffffffff;

   if ((x & 0xf0) == 0)
-      log  = 4, x <<= 4;
+      lg2  = 4, x <<= 4;

   if ((x & 0xc0) == 0)
-      log += 2, x <<= 2;
+      lg2 += 2, x <<= 2;

   if ((x & 0x80) == 0)
-      log += 1, x <<= 1;
+      lg2 += 1, x <<= 1;

   /* result is at most 19 bits, so this cast is safe: */
-   return (png_int_32)((log << 16) + ((png_8bit_l2[x-128]+32768)>>16));
+   return (png_int_32)((lg2 << 16) + ((png_8bit_l2[x-128]+32768)>>16));
 }

 /* The above gives exact (to 16 binary places) log2 values for 8 bit images,
@@ -1848,29 +1847,29 @@ png_log8bit(unsigned int x)
 static png_int_32
 png_log16bit(png_uint_32 x)
 {
-   unsigned int log = 0;
+   unsigned int lg2 = 0;

   /* As above, but now the input has 16 bits. */
   if ((x &= 0xffff) == 0)
      return 0xffffffff;

   if ((x & 0xff00) == 0)
-      log  = 8, x <<= 8;
+      lg2  = 8, x <<= 8;

   if ((x & 0xf000) == 0)
-      log += 4, x <<= 4;
+      lg2 += 4, x <<= 4;

   if ((x & 0xc000) == 0)
-      log += 2, x <<= 2;
+      lg2 += 2, x <<= 2;

   if ((x & 0x8000) == 0)
-      log += 1, x <<= 1;
+      lg2 += 1, x <<= 1;

   /* Calculate the base logarithm from the top 8 bits as a 28 bit fractional
    * value.
    */
-   log <<= 28;
-   log += (png_8bit_l2[(x>>8)-128]+8) >> 4;
+   lg2 <<= 28;
+   lg2 += (png_8bit_l2[(x>>8)-128]+8) >> 4;

   /* Now we need to interpolate the factor, this requires a division by the top
    * 8 bits.  Do this with maximum precision.
@@ -1881,19 +1880,19 @@ png_log16bit(png_uint_32 x)
    * the value at 1<<16 (ignoring this) will be 0 or 1; this gives us exactly
    * 16 bits to interpolate to get the low bits of the result.  Round the
    * answer.  Note that the end point values are scaled by 64 to retain overall
-    * precision and that 'log' is current scaled by an extra 12 bits, so adjust
+    * precision and that 'lg2' is current scaled by an extra 12 bits, so adjust
    * the overall scaling by 6-12.  Round at every step.
    */
   x -= 1U << 24;

   if (x <= 65536U) /* <= '257' */
-      log += ((23591U * (65536U-x)) + (1U << (16+6-12-1))) >> (16+6-12);
+      lg2 += ((23591U * (65536U-x)) + (1U << (16+6-12-1))) >> (16+6-12);

   else
-      log -= ((23499U * (x-65536U)) + (1U << (16+6-12-1))) >> (16+6-12);
+      lg2 -= ((23499U * (x-65536U)) + (1U << (16+6-12-1))) >> (16+6-12);

   /* Safe, because the result can't have more than 20 bits: */
-   return (png_int_32)((log + 2048) >> 12);
+   return (png_int_32)((lg2 + 2048) >> 12);
 }

 /* The 'exp()' case must invert the above, taking a 20 bit fixed point
@@ -1988,10 +1987,10 @@ png_exp(png_fixed_point x)
 }

 static png_byte
-png_exp8bit(png_fixed_point log)
+png_exp8bit(png_fixed_point lg2)
 {
   /* Get a 32 bit value: */
-   png_uint_32 x = png_exp(log);
+   png_uint_32 x = png_exp(lg2);

   /* Convert the 32 bit value to 0..255 by multiplying by 256-1, note that the
    * second, rounding, step can't overflow because of the first, subtraction,
@@ -2002,10 +2001,10 @@ png_exp8bit(png_fixed_point log)
 }

 static png_uint_16
-png_exp16bit(png_fixed_point log)
+png_exp16bit(png_fixed_point lg2)
 {
   /* Get a 32 bit value: */
-   png_uint_32 x = png_exp(log);
+   png_uint_32 x = png_exp(lg2);

   /* Convert the 32 bit value to 0..65535 by multiplying by 65536-1: */
   x -= x >> 16;
@@ -2014,18 +2013,18 @@ png_exp16bit(png_fixed_point log)
 #endif /* FLOATING_ARITHMETIC */

 png_byte
-png_gamma_8bit_correct(unsigned int value, png_fixed_point gamma)
+png_gamma_8bit_correct(unsigned int value, png_fixed_point gamma_val)
 {
   if (value > 0 && value < 255)
   {
 #     ifdef PNG_FLOATING_ARITHMETIC_SUPPORTED
-         double r = floor(255*pow(value/255.,gamma*.00001)+.5);
+         double r = floor(255*pow(value/255.,gamma_val*.00001)+.5);
         return (png_byte)r;
 #     else
-         png_int_32 log = png_log8bit(value);
+         png_int_32 lg2 = png_log8bit(value);
         png_fixed_point res;

-         if (png_muldiv(&res, gamma, log, PNG_FP_1))
+         if (png_muldiv(&res, gamma_val, lg2, PNG_FP_1))
            return png_exp8bit(res);

         /* Overflow. */
@@ -2037,18 +2036,18 @@ png_gamma_8bit_correct(unsigned int value, png_fixed_point gamma)
 }

 png_uint_16
-png_gamma_16bit_correct(unsigned int value, png_fixed_point gamma)
+png_gamma_16bit_correct(unsigned int value, png_fixed_point gamma_val)
 {
   if (value > 0 && value < 65535)
   {
 #     ifdef PNG_FLOATING_ARITHMETIC_SUPPORTED
-         double r = floor(65535*pow(value/65535.,gamma*.00001)+.5);
+         double r = floor(65535*pow(value/65535.,gamma_val*.00001)+.5);
         return (png_uint_16)r;
 #     else
-         png_int_32 log = png_log16bit(value);
+         png_int_32 lg2 = png_log16bit(value);
         png_fixed_point res;

-         if (png_muldiv(&res, gamma, log, PNG_FP_1))
+         if (png_muldiv(&res, gamma_val, lg2, PNG_FP_1))
            return png_exp16bit(res);

         /* Overflow. */
@@ -2066,23 +2065,23 @@ png_gamma_16bit_correct(unsigned int value, png_fixed_point gamma)
 */
 png_uint_16 /* PRIVATE */
 png_gamma_correct(png_structp png_ptr, unsigned int value,
-    png_fixed_point gamma)
+    png_fixed_point gamma_val)
 {
   if (png_ptr->bit_depth == 8)
-      return png_gamma_8bit_correct(value, gamma);
+      return png_gamma_8bit_correct(value, gamma_val);

   else
-      return png_gamma_16bit_correct(value, gamma);
+      return png_gamma_16bit_correct(value, gamma_val);
 }

 /* This is the shared test on whether a gamma value is 'significant' - whether
 * it is worth doing gamma correction.
 */
 int /* PRIVATE */
-png_gamma_significant(png_fixed_point gamma)
+png_gamma_significant(png_fixed_point gamma_val)
 {
-   return gamma < PNG_FP_1 - PNG_GAMMA_THRESHOLD_FIXED ||
-       gamma > PNG_FP_1 + PNG_GAMMA_THRESHOLD_FIXED;
+   return gamma_val < PNG_FP_1 - PNG_GAMMA_THRESHOLD_FIXED ||
+       gamma_val > PNG_FP_1 + PNG_GAMMA_THRESHOLD_FIXED;
 }

 /* Internal function to build a single 16 bit table - the table consists of
@@ -2095,7 +2094,7 @@ png_gamma_significant(png_fixed_point gamma)
 */
 static void
 png_build_16bit_table(png_structp png_ptr, png_uint_16pp *ptable,
-   PNG_CONST unsigned int shift, PNG_CONST png_fixed_point gamma)
+   PNG_CONST unsigned int shift, PNG_CONST png_fixed_point gamma_val)
 {
   /* Various values derived from 'shift': */
   PNG_CONST unsigned int num = 1U << (8U - shift);
@@ -2114,7 +2113,7 @@ png_build_16bit_table(png_structp png_ptr, png_uint_16pp *ptable,
      /* The 'threshold' test is repeated here because it can arise for one of
       * the 16 bit tables even if the others don't hit it.
       */
-      if (png_gamma_significant(gamma))
+      if (png_gamma_significant(gamma_val))
      {
         /* The old code would overflow at the end and this would cause the
          * 'pow' function to return a result >1, resulting in an
@@ -2130,13 +2129,13 @@ png_build_16bit_table(png_structp png_ptr, png_uint_16pp *ptable,
            png_uint_32 ig = (j << (8-shift)) + i;
 #           ifdef PNG_FLOATING_ARITHMETIC_SUPPORTED
               /* Inline the 'max' scaling operation: */
-               double d = floor(65535*pow(ig/(double)max, gamma*.00001)+.5);
+               double d = floor(65535*pow(ig/(double)max, gamma_val*.00001)+.5);
               sub_table[j] = (png_uint_16)d;
 #           else
               if (shift)
                  ig = (ig * 65535U + max_by_2)/max;

-               sub_table[j] = png_gamma_16bit_correct(ig, gamma);
+               sub_table[j] = png_gamma_16bit_correct(ig, gamma_val);
 #           endif
         }
      }
@@ -2163,7 +2162,7 @@ png_build_16bit_table(png_structp png_ptr, png_uint_16pp *ptable,
 */
 static void
 png_build_16to8_table(png_structp png_ptr, png_uint_16pp *ptable,
-   PNG_CONST unsigned int shift, PNG_CONST png_fixed_point gamma)
+   PNG_CONST unsigned int shift, PNG_CONST png_fixed_point gamma_val)
 {
   PNG_CONST unsigned int num = 1U << (8U - shift);
   PNG_CONST unsigned int max = (1U << (16U - shift))-1U;
@@ -2181,7 +2180,7 @@ png_build_16to8_table(png_structp png_ptr, png_uint_16pp *ptable,
      table[i] = (png_uint_16p)png_malloc(png_ptr,
          256 * png_sizeof(png_uint_16));

-   /* 'gamma' is set to the reciprocal of the value calculated above, so
+   /* 'gamma_val' is set to the reciprocal of the value calculated above, so
    * pow(out,g) is an *input* value.  'last' is the last input value set.
    *
    * In the loop 'i' is used to find output values.  Since the output is 8
@@ -2204,7 +2203,7 @@ png_build_16to8_table(png_structp png_ptr, png_uint_16pp *ptable,
      png_uint_16 out = (png_uint_16)(i * 257U); /* 16 bit output value */

      /* Find the boundary value in 16 bits: */
-      png_uint_32 bound = png_gamma_16bit_correct(out+128U, gamma);
+      png_uint_32 bound = png_gamma_16bit_correct(out+128U, gamma_val);

      /* Adjust (round) to (16-shift) bits: */
      bound = (bound * max + 32768U)/65535U + 1U;
@@ -2230,13 +2229,13 @@ png_build_16to8_table(png_structp png_ptr, png_uint_16pp *ptable,
 */
 static void
 png_build_8bit_table(png_structp png_ptr, png_bytepp ptable,
-   PNG_CONST png_fixed_point gamma)
+   PNG_CONST png_fixed_point gamma_val)
 {
   unsigned int i;
   png_bytep table = *ptable = (png_bytep)png_malloc(png_ptr, 256);

-   if (png_gamma_significant(gamma)) for (i=0; i<256; i++)
-      table[i] = png_gamma_8bit_correct(i, gamma);
+   if (png_gamma_significant(gamma_val)) for (i=0; i<256; i++)
+      table[i] = png_gamma_8bit_correct(i, gamma_val);

   else for (i=0; i<256; ++i)
      table[i] = (png_byte)i;
--- a/png.h
+++ b/png.h
--- a/pngconf.h
+++ b/pngconf.h
@@ -1,9 +1,9 @@

 /* pngconf.h - machine configurable file for libpng
 *
- * libpng version 1.5.0beta55 - (PENDING RELEASE)
+ * libpng version 1.5.2rc01 - (PENDING RELEASE)
 *
- * Copyright (c) 1998-2010 Glenn Randers-Pehrson
+ * Copyright (c) 1998-2011 Glenn Randers-Pehrson
 * (Version 0.96 Copyright (c) 1996, 1997 Andreas Dilger)
 * (Version 0.88 Copyright (c) 1995, 1996 Guy Eric Schalnat, Group 42, Inc.)
 *
@@ -69,7 +69,8 @@
 * below) but still have compiler specific implementations, others
 * may be changed on a per-file basis when compiling against libpng.
 */
-/* This macro protects us against machines that don't have function
+
+/* The PNGARG macro protects us against machines that don't have function
 * prototypes (ie K&R style headers).  If your compiler does not handle
 * function prototypes, define this macro and use the included ansi2knr.
 * I've always been able to use _NO_PROTO as the indicator, but you may
@@ -281,46 +282,47 @@
 #  endif
 #endif

-/* THe following complexity is concerned with getting the 'attributes' of the
- * declared function in the correct place.  This potentially requires a separate
- * PNG_EXPORT function for every compiler.
+/* In 1.5.2 the definition of PNG_FUNCTION has been changed to always treat
+ * 'attributes' as a storage class - the attributes go at the start of the
+ * function definition, and attributes are always appended regardless of the
+ * compiler.  This considerably simplifies these macros but may cause problems
+ * if any compilers both need function attributes and fail to handle them as
+ * a storage class (this is unlikely.)
 */
 #ifndef PNG_FUNCTION
-#  ifdef __GNUC__
-#     define PNG_FUNCTION(type, name, args, attributes)\
-         attributes type name args
-#  else /* !GNUC */
-#     ifdef _MSC_VER
-#        define PNG_FUNCTION(type, name, args, attributes)\
-         attributes type name args
-#     else /* !MSC */
-#        define PNG_FUNCTION(type, name, args, attributes)\
-            type name args
-#     endif
-#  endif
+#  define PNG_FUNCTION(type, name, args, attributes) attributes type name args
 #endif

 #ifndef PNG_EXPORT_TYPE
 #  define PNG_EXPORT_TYPE(type) PNG_IMPEXP type
 #endif

-#ifndef PNG_EXPORT
   /* The ordinal value is only relevant when preprocessing png.h for symbol
-    * table entries.
+    * table entries, so we discard it here.  See the .dfn files in the
+    * scripts directory.
    */
-#  define PNG_EXPORT(type, name, args, attributes, ordinal)\
-      extern PNG_FUNCTION(PNG_EXPORT_TYPE(type),(PNGAPI name),PNGARG(args),\
-         attributes)
+#ifndef PNG_EXPORTA
+
+#  define PNG_EXPORTA(ordinal, type, name, args, attributes)\
+      PNG_FUNCTION(PNG_EXPORT_TYPE(type),(PNGAPI name),PNGARG(args), \
+        extern attributes)
 #endif

+/* ANSI-C (C90) does not permit a macro to be invoked with an empty argument,
+ * so make something non-empty to satisfy the requirement:
+ */
+#define PNG_EMPTY /*empty list*/
+
+#define PNG_EXPORT(ordinal, type, name, args)\
+   PNG_EXPORTA(ordinal, type, name, args, PNG_EMPTY)
+
 /* Use PNG_REMOVED to comment out a removed interface. */
 #ifndef PNG_REMOVED
-#  define PNG_REMOVED(type, name, args, attributes, ordinal)
+#  define PNG_REMOVED(ordinal, type, name, args, attributes)
 #endif

 #ifndef PNG_CALLBACK
-#  define PNG_CALLBACK(type, name, args, attributes)\
-   type (PNGCBAPI name) PNGARG(args) attributes
+#  define PNG_CALLBACK(type, name, args) type (PNGCBAPI name) PNGARG(args)
 #endif

 /* Support for compiler specific function attributes.  These are used
@@ -342,7 +344,7 @@
   * functions in png.h will generate compiler warnings.  Added at libpng
   * version 1.2.41.
   */
-#  ifdef __GNUC__
+#  if defined(__GNUC__)
 #    ifndef PNG_USE_RESULT
 #      define PNG_USE_RESULT __attribute__((__warn_unused_result__))
 #    endif
@@ -350,7 +352,21 @@
 #      define PNG_NORETURN   __attribute__((__noreturn__))
 #    endif
 #    ifndef PNG_PTR_NORETURN
-#      define PNG_PTR_NORETURN   __attribute__((__noreturn__))
+       /* It's not enough to have the compiler be the correct compiler at
+        * this point - it's necessary for the library (which defines
+        * the type of the library longjmp) to also be the GNU library.
+        * This is because many systems use the GNU compiler with a
+        * non-GNU libc implementation.  Min/GW headers are also compatible
+        * with GCC as well as uclibc, so it seems best to exclude known
+        * problem libcs here rather than just including known libcs.
+        *
+        * NOTE: this relies on the only use of PNG_PTR_NORETURN being with
+        * the system longjmp.  If the same type is used elsewhere then this
+        * will need to be changed.
+        */
+#      if !defined(__CYGWIN__)
+#         define PNG_PTR_NORETURN   __attribute__((__noreturn__))
+#      endif
 #    endif
 #    ifndef PNG_ALLOCATED
 #      define PNG_ALLOCATED  __attribute__((__malloc__))
@@ -375,18 +391,19 @@
 #          define PNG_PRIVATE \
            __attribute__((__deprecated__))
 #        endif
-#      endif /* PNG_PRIVATE */
+#      endif
 #    endif /* PNGLIB_BUILD */
 #  endif /* __GNUC__ */
-#  ifdef _MSC_VER /* may need to check value */
+
+#  if defined(_MSC_VER)  && (_MSC_VER >= 1300)
 #    ifndef PNG_USE_RESULT
-#      define PNG_USE_RESULT /*not supported*/
+#      define PNG_USE_RESULT /* not supported */
 #    endif
 #    ifndef PNG_NORETURN
 #      define PNG_NORETURN   __declspec(noreturn)
 #    endif
 #    ifndef PNG_PTR_NORETURN
-#      define PNG_PTR_NORETURN /*not supported*/
+#      define PNG_PTR_NORETURN /* not supported */
 #    endif
 #    ifndef PNG_ALLOCATED
 #      define PNG_ALLOCATED __declspec(restrict)
@@ -405,9 +422,9 @@
 #      endif
 #      ifndef PNG_PRIVATE
 #        define PNG_PRIVATE __declspec(deprecated)
-#      endif /* PNG_PRIVATE */
+#      endif
 #    endif /* PNGLIB_BUILD */
-#  endif /* __GNUC__ */
+#  endif /* _MSC_VER */
 #endif /* PNG_PEDANTIC_WARNINGS */

 #ifndef PNG_DEPRECATED
@@ -419,6 +436,9 @@
 #ifndef PNG_NORETURN
 #  define PNG_NORETURN    /* This function does not return */
 #endif
+#ifndef PNG_PTR_NORETURN
+#  define PNG_PTR_NORETURN /* This function does not return */
+#endif
 #ifndef PNG_ALLOCATED
 #  define PNG_ALLOCATED   /* The result of the function is new memory */
 #endif
@@ -430,18 +450,18 @@
 #endif
 #ifndef PNG_FP_EXPORT     /* A floating point API. */
 #  ifdef PNG_FLOATING_POINT_SUPPORTED
-#     define PNG_FP_EXPORT(type, name, args, attributes, ordinal)\
-         PNG_EXPORT(type, name, args, attributes, ordinal)
+#     define PNG_FP_EXPORT(ordinal, type, name, args)\
+         PNG_EXPORT(ordinal, type, name, args)
 #  else                   /* No floating point APIs */
-#     define PNG_FP_EXPORT(type, name, args, attributes, ordinal)
+#     define PNG_FP_EXPORT(ordinal, type, name, args)
 #  endif
 #endif
 #ifndef PNG_FIXED_EXPORT  /* A fixed point API. */
 #  ifdef PNG_FIXED_POINT_SUPPORTED
-#     define PNG_FIXED_EXPORT(type, name, args, attributes, ordinal)\
-         PNG_EXPORT(type, name, args, attributes, ordinal)
+#     define PNG_FIXED_EXPORT(ordinal, type, name, args)\
+         PNG_EXPORT(ordinal, type, name, args)
 #  else                   /* No fixed point APIs */
-#     define PNG_FIXED_EXPORT(type, name, args, attributes, ordinal)
+#     define PNG_FIXED_EXPORT(ordinal, type, name, args)
 #  endif
 #endif

--- a/pngdebug.h
+++ b/pngdebug.h
@@ -1,11 +1,11 @@

 /* pngdebug.h - Debugging macros for libpng, also used in pngtest.c
 *
- * Copyright (c) 1998-2010 Glenn Randers-Pehrson
+ * Copyright (c) 1998-2011 Glenn Randers-Pehrson
 * (Version 0.96 Copyright (c) 1996, 1997 Andreas Dilger)
 * (Version 0.88 Copyright (c) 1995, 1996 Guy Eric Schalnat, Group 42, Inc.)
 *
- * Last changed in libpng version 1.5.0 - (PENDING RELEASE)
+ * Last changed in libpng 1.5.0 [January 6, 2011]
 *
 * This code is released under the libpng license.
 * For conditions of distribution and use, see the disclaimer
--- a/pngerror.c
+++ b/pngerror.c
@@ -1,8 +1,8 @@

 /* pngerror.c - stub functions for i/o and memory allocation
 *
- * Last changed in libpng 1.5.0 [(PENDING RELEASE)]
- * Copyright (c) 1998-2010 Glenn Randers-Pehrson
+ * Last changed in libpng 1.5.1 [February 3, 2011]
+ * Copyright (c) 1998-2011 Glenn Randers-Pehrson
 * (Version 0.96 Copyright (c) 1996, 1997 Andreas Dilger)
 * (Version 0.88 Copyright (c) 1995, 1996 Guy Eric Schalnat, Group 42, Inc.)
 *
@@ -322,7 +322,7 @@ png_default_error,(png_structp png_ptr, png_const_charp error_message),
   }
 #endif
 #ifndef PNG_CONSOLE_IO_SUPPORTED
-   error_message = error_message; /* Make compiler happy */
+   PNG_UNUSED(error_message) /* Make compiler happy */
 #endif
   png_longjmp(png_ptr, 1);
 }
@@ -394,9 +394,9 @@ png_default_warning(png_structp png_ptr, png_const_charp warning_message)
      fprintf(stderr, PNG_STRING_NEWLINE);
   }
 #else
-   warning_message = warning_message; /* Make compiler happy */
+   PNG_UNUSED(warning_message) /* Make compiler happy */
 #endif
-   png_ptr = png_ptr; /* Make compiler happy */
+   PNG_UNUSED(png_ptr) /* Make compiler happy */
 }
 #endif /* PNG_WARNINGS_SUPPORTED */

@@ -423,7 +423,7 @@ png_set_error_fn(png_structp png_ptr, png_voidp error_ptr,
 * pointer before png_write_destroy and png_read_destroy are called.
 */
 png_voidp PNGAPI
-png_get_error_ptr(png_structp png_ptr)
+png_get_error_ptr(png_const_structp png_ptr)
 {
   if (png_ptr == NULL)
      return NULL;
--- a/pngget.c
+++ b/pngget.c
@@ -1,8 +1,8 @@

 /* pngget.c - retrieval of values from info struct
 *
- * Last changed in libpng 1.5.0 [(PENDING RELEASE)]
- * Copyright (c) 1998-2010 Glenn Randers-Pehrson
+ * Last changed in libpng 1.5.1 [February 3, 2011]
+ * Copyright (c) 1998-2011 Glenn Randers-Pehrson
 * (Version 0.96 Copyright (c) 1996, 1997 Andreas Dilger)
 * (Version 0.88 Copyright (c) 1995, 1996 Guy Eric Schalnat, Group 42, Inc.)
 *
@@ -17,7 +17,8 @@
 #if defined(PNG_READ_SUPPORTED) || defined(PNG_WRITE_SUPPORTED)

 png_uint_32 PNGAPI
-png_get_valid(png_structp png_ptr, png_infop info_ptr, png_uint_32 flag)
+png_get_valid(png_const_structp png_ptr, png_const_infop info_ptr,
+    png_uint_32 flag)
 {
   if (png_ptr != NULL && info_ptr != NULL)
      return(info_ptr->valid & flag);
@@ -26,7 +27,7 @@ png_get_valid(png_structp png_ptr, png_infop info_ptr, png_uint_32 flag)
 }

 png_size_t PNGAPI
-png_get_rowbytes(png_structp png_ptr, png_infop info_ptr)
+png_get_rowbytes(png_const_structp png_ptr, png_const_infop info_ptr)
 {
   if (png_ptr != NULL && info_ptr != NULL)
      return(info_ptr->rowbytes);
@@ -36,7 +37,7 @@ png_get_rowbytes(png_structp png_ptr, png_infop info_ptr)

 #ifdef PNG_INFO_IMAGE_SUPPORTED
 png_bytepp PNGAPI
-png_get_rows(png_structp png_ptr, png_infop info_ptr)
+png_get_rows(png_const_structp png_ptr, png_const_infop info_ptr)
 {
   if (png_ptr != NULL && info_ptr != NULL)
      return(info_ptr->row_pointers);
@@ -48,7 +49,7 @@ png_get_rows(png_structp png_ptr, png_infop info_ptr)
 #ifdef PNG_EASY_ACCESS_SUPPORTED
 /* Easy access to info, added in libpng-0.99 */
 png_uint_32 PNGAPI
-png_get_image_width(png_structp png_ptr, png_infop info_ptr)
+png_get_image_width(png_const_structp png_ptr, png_const_infop info_ptr)
 {
   if (png_ptr != NULL && info_ptr != NULL)
      return info_ptr->width;
@@ -57,7 +58,7 @@ png_get_image_width(png_structp png_ptr, png_infop info_ptr)
 }

 png_uint_32 PNGAPI
-png_get_image_height(png_structp png_ptr, png_infop info_ptr)
+png_get_image_height(png_const_structp png_ptr, png_const_infop info_ptr)
 {
   if (png_ptr != NULL && info_ptr != NULL)
      return info_ptr->height;
@@ -66,7 +67,7 @@ png_get_image_height(png_structp png_ptr, png_infop info_ptr)
 }

 png_byte PNGAPI
-png_get_bit_depth(png_structp png_ptr, png_infop info_ptr)
+png_get_bit_depth(png_const_structp png_ptr, png_const_infop info_ptr)
 {
   if (png_ptr != NULL && info_ptr != NULL)
      return info_ptr->bit_depth;
@@ -75,7 +76,7 @@ png_get_bit_depth(png_structp png_ptr, png_infop info_ptr)
 }

 png_byte PNGAPI
-png_get_color_type(png_structp png_ptr, png_infop info_ptr)
+png_get_color_type(png_const_structp png_ptr, png_const_infop info_ptr)
 {
   if (png_ptr != NULL && info_ptr != NULL)
      return info_ptr->color_type;
@@ -84,7 +85,7 @@ png_get_color_type(png_structp png_ptr, png_infop info_ptr)
 }

 png_byte PNGAPI
-png_get_filter_type(png_structp png_ptr, png_infop info_ptr)
+png_get_filter_type(png_const_structp png_ptr, png_const_infop info_ptr)
 {
   if (png_ptr != NULL && info_ptr != NULL)
      return info_ptr->filter_type;
@@ -93,7 +94,7 @@ png_get_filter_type(png_structp png_ptr, png_infop info_ptr)
 }

 png_byte PNGAPI
-png_get_interlace_type(png_structp png_ptr, png_infop info_ptr)
+png_get_interlace_type(png_const_structp png_ptr, png_const_infop info_ptr)
 {
   if (png_ptr != NULL && info_ptr != NULL)
      return info_ptr->interlace_type;
@@ -102,7 +103,7 @@ png_get_interlace_type(png_structp png_ptr, png_infop info_ptr)
 }

 png_byte PNGAPI
-png_get_compression_type(png_structp png_ptr, png_infop info_ptr)
+png_get_compression_type(png_const_structp png_ptr, png_const_infop info_ptr)
 {
   if (png_ptr != NULL && info_ptr != NULL)
      return info_ptr->compression_type;
@@ -111,7 +112,7 @@ png_get_compression_type(png_structp png_ptr, png_infop info_ptr)
 }

 png_uint_32 PNGAPI
-png_get_x_pixels_per_meter(png_structp png_ptr, png_infop info_ptr)
+png_get_x_pixels_per_meter(png_const_structp png_ptr, png_const_infop info_ptr)
 {
 #ifdef PNG_pHYs_SUPPORTED
   if (png_ptr != NULL && info_ptr != NULL && (info_ptr->valid & PNG_INFO_pHYs))
@@ -128,7 +129,7 @@ png_get_x_pixels_per_meter(png_structp png_ptr, png_infop info_ptr)
 }

 png_uint_32 PNGAPI
-png_get_y_pixels_per_meter(png_structp png_ptr, png_infop info_ptr)
+png_get_y_pixels_per_meter(png_const_structp png_ptr, png_const_infop info_ptr)
 {
 #ifdef PNG_pHYs_SUPPORTED
   if (png_ptr != NULL && info_ptr != NULL && (info_ptr->valid & PNG_INFO_pHYs))
@@ -145,7 +146,7 @@ png_get_y_pixels_per_meter(png_structp png_ptr, png_infop info_ptr)
 }

 png_uint_32 PNGAPI
-png_get_pixels_per_meter(png_structp png_ptr, png_infop info_ptr)
+png_get_pixels_per_meter(png_const_structp png_ptr, png_const_infop info_ptr)
 {
 #ifdef PNG_pHYs_SUPPORTED
   if (png_ptr != NULL && info_ptr != NULL && (info_ptr->valid & PNG_INFO_pHYs))
@@ -163,7 +164,7 @@ png_get_pixels_per_meter(png_structp png_ptr, png_infop info_ptr)

 #ifdef PNG_FLOATING_POINT_SUPPORTED
 float PNGAPI
-png_get_pixel_aspect_ratio(png_structp png_ptr, png_infop info_ptr)
+png_get_pixel_aspect_ratio(png_const_structp png_ptr, png_const_infop info_ptr)
 {
 #ifdef PNG_READ_pHYs_SUPPORTED
   if (png_ptr != NULL && info_ptr != NULL && (info_ptr->valid & PNG_INFO_pHYs))
@@ -182,7 +183,8 @@ png_get_pixel_aspect_ratio(png_structp png_ptr, png_infop info_ptr)

 #ifdef PNG_FIXED_POINT_SUPPORTED
 png_fixed_point PNGAPI
-png_get_pixel_aspect_ratio_fixed(png_structp png_ptr, png_infop info_ptr)
+png_get_pixel_aspect_ratio_fixed(png_const_structp png_ptr,
+    png_const_infop info_ptr)
 {
 #ifdef PNG_READ_pHYs_SUPPORTED
   if (png_ptr != NULL && info_ptr != NULL && (info_ptr->valid & PNG_INFO_pHYs)
@@ -208,7 +210,7 @@ png_get_pixel_aspect_ratio_fixed(png_structp png_ptr, png_infop info_ptr)
 #endif

 png_int_32 PNGAPI
-png_get_x_offset_microns(png_structp png_ptr, png_infop info_ptr)
+png_get_x_offset_microns(png_const_structp png_ptr, png_const_infop info_ptr)
 {
 #ifdef PNG_oFFs_SUPPORTED
   if (png_ptr != NULL && info_ptr != NULL && (info_ptr->valid & PNG_INFO_oFFs))
@@ -224,7 +226,7 @@ png_get_x_offset_microns(png_structp png_ptr, png_infop info_ptr)
 }

 png_int_32 PNGAPI
-png_get_y_offset_microns(png_structp png_ptr, png_infop info_ptr)
+png_get_y_offset_microns(png_const_structp png_ptr, png_const_infop info_ptr)
 {
 #ifdef PNG_oFFs_SUPPORTED
   if (png_ptr != NULL && info_ptr != NULL && (info_ptr->valid & PNG_INFO_oFFs))
@@ -240,7 +242,7 @@ png_get_y_offset_microns(png_structp png_ptr, png_infop info_ptr)
 }

 png_int_32 PNGAPI
-png_get_x_offset_pixels(png_structp png_ptr, png_infop info_ptr)
+png_get_x_offset_pixels(png_const_structp png_ptr, png_const_infop info_ptr)
 {
 #ifdef PNG_oFFs_SUPPORTED
   if (png_ptr != NULL && info_ptr != NULL && (info_ptr->valid & PNG_INFO_oFFs))
@@ -256,7 +258,7 @@ png_get_x_offset_pixels(png_structp png_ptr, png_infop info_ptr)
 }

 png_int_32 PNGAPI
-png_get_y_offset_pixels(png_structp png_ptr, png_infop info_ptr)
+png_get_y_offset_pixels(png_const_structp png_ptr, png_const_infop info_ptr)
 {
 #ifdef PNG_oFFs_SUPPORTED
   if (png_ptr != NULL && info_ptr != NULL && (info_ptr->valid & PNG_INFO_oFFs))
@@ -305,19 +307,19 @@ ppi_from_ppm(png_uint_32 ppm)
 }

 png_uint_32 PNGAPI
-png_get_pixels_per_inch(png_structp png_ptr, png_infop info_ptr)
+png_get_pixels_per_inch(png_const_structp png_ptr, png_const_infop info_ptr)
 {
   return ppi_from_ppm(png_get_pixels_per_meter(png_ptr, info_ptr));
 }

 png_uint_32 PNGAPI
-png_get_x_pixels_per_inch(png_structp png_ptr, png_infop info_ptr)
+png_get_x_pixels_per_inch(png_const_structp png_ptr, png_const_infop info_ptr)
 {
   return ppi_from_ppm(png_get_x_pixels_per_meter(png_ptr, info_ptr));
 }

 png_uint_32 PNGAPI
-png_get_y_pixels_per_inch(png_structp png_ptr, png_infop info_ptr)
+png_get_y_pixels_per_inch(png_const_structp png_ptr, png_const_infop info_ptr)
 {
   return ppi_from_ppm(png_get_y_pixels_per_meter(png_ptr, info_ptr));
 }
@@ -335,7 +337,8 @@ png_fixed_inches_from_microns(png_structp png_ptr, png_int_32 microns)
 }

 png_fixed_point PNGAPI
-png_get_x_offset_inches_fixed(png_structp png_ptr, png_infop info_ptr)
+png_get_x_offset_inches_fixed(png_structp png_ptr,
+    png_const_infop info_ptr)
 {
   return png_fixed_inches_from_microns(png_ptr,
       png_get_x_offset_microns(png_ptr, info_ptr));
@@ -344,7 +347,8 @@ png_get_x_offset_inches_fixed(png_structp png_ptr, png_infop info_ptr)

 #ifdef PNG_FIXED_POINT_SUPPORTED
 png_fixed_point PNGAPI
-png_get_y_offset_inches_fixed(png_structp png_ptr, png_infop info_ptr)
+png_get_y_offset_inches_fixed(png_structp png_ptr,
+    png_const_infop info_ptr)
 {
   return png_fixed_inches_from_microns(png_ptr,
       png_get_y_offset_microns(png_ptr, info_ptr));
@@ -353,7 +357,7 @@ png_get_y_offset_inches_fixed(png_structp png_ptr, png_infop info_ptr)

 #ifdef PNG_FLOATING_POINT_SUPPORTED
 float PNGAPI
-png_get_x_offset_inches(png_structp png_ptr, png_infop info_ptr)
+png_get_x_offset_inches(png_const_structp png_ptr, png_const_infop info_ptr)
 {
   /* To avoid the overflow do the conversion directly in floating
    * point.
@@ -364,7 +368,7 @@ png_get_x_offset_inches(png_structp png_ptr, png_infop info_ptr)

 #ifdef PNG_FLOATING_POINT_SUPPORTED
 float PNGAPI
-png_get_y_offset_inches(png_structp png_ptr, png_infop info_ptr)
+png_get_y_offset_inches(png_const_structp png_ptr, png_const_infop info_ptr)
 {
   /* To avoid the overflow do the conversion directly in floating
    * point.
@@ -375,7 +379,7 @@ png_get_y_offset_inches(png_structp png_ptr, png_infop info_ptr)

 #ifdef PNG_pHYs_SUPPORTED
 png_uint_32 PNGAPI
-png_get_pHYs_dpi(png_structp png_ptr, png_infop info_ptr,
+png_get_pHYs_dpi(png_const_structp png_ptr, png_const_infop info_ptr,
    png_uint_32 *res_x, png_uint_32 *res_y, int *unit_type)
 {
   png_uint_32 retval = 0;
@@ -419,7 +423,7 @@ png_get_pHYs_dpi(png_structp png_ptr, png_infop info_ptr,
 #endif  /* PNG_EASY_ACCESS_SUPPORTED */

 png_byte PNGAPI
-png_get_channels(png_structp png_ptr, png_infop info_ptr)
+png_get_channels(png_const_structp png_ptr, png_const_infop info_ptr)
 {
   if (png_ptr != NULL && info_ptr != NULL)
      return(info_ptr->channels);
@@ -428,7 +432,7 @@ png_get_channels(png_structp png_ptr, png_infop info_ptr)
 }

 png_const_bytep PNGAPI
-png_get_signature(png_structp png_ptr, png_infop info_ptr)
+png_get_signature(png_const_structp png_ptr, png_infop info_ptr)
 {
   if (png_ptr != NULL && info_ptr != NULL)
      return(info_ptr->signature);
@@ -438,7 +442,7 @@ png_get_signature(png_structp png_ptr, png_infop info_ptr)

 #ifdef PNG_bKGD_SUPPORTED
 png_uint_32 PNGAPI
-png_get_bKGD(png_structp png_ptr, png_infop info_ptr,
+png_get_bKGD(png_const_structp png_ptr, png_infop info_ptr,
   png_color_16p *background)
 {
   if (png_ptr != NULL && info_ptr != NULL && (info_ptr->valid & PNG_INFO_bKGD)
@@ -457,7 +461,7 @@ png_get_bKGD(png_structp png_ptr, png_infop info_ptr,
 #ifdef PNG_cHRM_SUPPORTED
 #  ifdef PNG_FLOATING_POINT_SUPPORTED
 png_uint_32 PNGAPI
-png_get_cHRM(png_structp png_ptr, png_infop info_ptr,
+png_get_cHRM(png_const_structp png_ptr, png_const_infop info_ptr,
    double *white_x, double *white_y, double *red_x, double *red_y,
    double *green_x, double *green_y, double *blue_x, double *blue_y)
 {
@@ -490,7 +494,7 @@ png_get_cHRM(png_structp png_ptr, png_infop info_ptr,

 #  ifdef PNG_FIXED_POINT_SUPPORTED
 png_uint_32 PNGAPI
-png_get_cHRM_fixed(png_structp png_ptr, png_infop info_ptr,
+png_get_cHRM_fixed(png_const_structp png_ptr, png_const_infop info_ptr,
    png_fixed_point *white_x, png_fixed_point *white_y, png_fixed_point *red_x,
    png_fixed_point *red_y, png_fixed_point *green_x, png_fixed_point *green_y,
    png_fixed_point *blue_x, png_fixed_point *blue_y)
@@ -525,7 +529,7 @@ png_get_cHRM_fixed(png_structp png_ptr, png_infop info_ptr,

 #ifdef PNG_gAMA_SUPPORTED
 png_uint_32 PNGFAPI
-png_get_gAMA_fixed(png_structp png_ptr, png_infop info_ptr,
+png_get_gAMA_fixed(png_const_structp png_ptr, png_const_infop info_ptr,
    png_fixed_point *file_gamma)
 {
   png_debug1(1, "in %s retrieval function", "gAMA");
@@ -541,7 +545,8 @@ png_get_gAMA_fixed(png_structp png_ptr, png_infop info_ptr,
 }
 #  ifdef PNG_FLOATING_POINT_SUPPORTED
 png_uint_32 PNGAPI
-png_get_gAMA(png_structp png_ptr, png_infop info_ptr, double *file_gamma)
+png_get_gAMA(png_const_structp png_ptr, png_const_infop info_ptr,
+    double *file_gamma)
 {
   png_fixed_point igamma;
   png_uint_32 ok = png_get_gAMA_fixed(png_ptr, info_ptr, &igamma);
@@ -557,7 +562,8 @@ png_get_gAMA(png_structp png_ptr, png_infop info_ptr, double *file_gamma)

 #ifdef PNG_sRGB_SUPPORTED
 png_uint_32 PNGAPI
-png_get_sRGB(png_structp png_ptr, png_infop info_ptr, int *file_srgb_intent)
+png_get_sRGB(png_const_structp png_ptr, png_const_infop info_ptr,
+    int *file_srgb_intent)
 {
   png_debug1(1, "in %s retrieval function", "sRGB");

@@ -574,7 +580,7 @@ png_get_sRGB(png_structp png_ptr, png_infop info_ptr, int *file_srgb_intent)

 #ifdef PNG_iCCP_SUPPORTED
 png_uint_32 PNGAPI
-png_get_iCCP(png_structp png_ptr, png_infop info_ptr,
+png_get_iCCP(png_const_structp png_ptr, png_const_infop info_ptr,
    png_charpp name, int *compression_type,
    png_bytepp profile, png_uint_32 *proflen)
 {
@@ -599,7 +605,7 @@ png_get_iCCP(png_structp png_ptr, png_infop info_ptr,

 #ifdef PNG_sPLT_SUPPORTED
 png_uint_32 PNGAPI
-png_get_sPLT(png_structp png_ptr, png_infop info_ptr,
+png_get_sPLT(png_const_structp png_ptr, png_const_infop info_ptr,
    png_sPLT_tpp spalettes)
 {
   if (png_ptr != NULL && info_ptr != NULL && spalettes != NULL)
@@ -614,7 +620,8 @@ png_get_sPLT(png_structp png_ptr, png_infop info_ptr,

 #ifdef PNG_hIST_SUPPORTED
 png_uint_32 PNGAPI
-png_get_hIST(png_structp png_ptr, png_infop info_ptr, png_uint_16p *hist)
+png_get_hIST(png_const_structp png_ptr, png_const_infop info_ptr,
+    png_uint_16p *hist)
 {
   png_debug1(1, "in %s retrieval function", "hIST");

@@ -670,7 +677,7 @@ png_get_IHDR(png_structp png_ptr, png_infop info_ptr,

 #ifdef PNG_oFFs_SUPPORTED
 png_uint_32 PNGAPI
-png_get_oFFs(png_structp png_ptr, png_infop info_ptr,
+png_get_oFFs(png_const_structp png_ptr, png_const_infop info_ptr,
    png_int_32 *offset_x, png_int_32 *offset_y, int *unit_type)
 {
   png_debug1(1, "in %s retrieval function", "oFFs");
@@ -690,7 +697,7 @@ png_get_oFFs(png_structp png_ptr, png_infop info_ptr,

 #ifdef PNG_pCAL_SUPPORTED
 png_uint_32 PNGAPI
-png_get_pCAL(png_structp png_ptr, png_infop info_ptr,
+png_get_pCAL(png_const_structp png_ptr, png_const_infop info_ptr,
    png_charp *purpose, png_int_32 *X0, png_int_32 *X1, int *type, int *nparams,
    png_charp *units, png_charpp *params)
 {
@@ -718,7 +725,7 @@ png_get_pCAL(png_structp png_ptr, png_infop info_ptr,
 #  ifdef PNG_FIXED_POINT_SUPPORTED
 #    ifdef PNG_FLOATING_ARITHMETIC_SUPPORTED
 png_uint_32 PNGAPI
-png_get_sCAL_fixed(png_structp png_ptr, png_infop info_ptr,
+png_get_sCAL_fixed(png_structp png_ptr, png_const_infop info_ptr,
    int *unit, png_fixed_point *width, png_fixed_point *height)
 {
   if (png_ptr != NULL && info_ptr != NULL &&
@@ -738,7 +745,7 @@ png_get_sCAL_fixed(png_structp png_ptr, png_infop info_ptr,
 #  endif /* FIXED_POINT */
 #  ifdef PNG_FLOATING_POINT_SUPPORTED
 png_uint_32 PNGAPI
-png_get_sCAL(png_structp png_ptr, png_infop info_ptr,
+png_get_sCAL(png_const_structp png_ptr, png_const_infop info_ptr,
    int *unit, double *width, double *height)
 {
   if (png_ptr != NULL && info_ptr != NULL &&
@@ -754,7 +761,7 @@ png_get_sCAL(png_structp png_ptr, png_infop info_ptr,
 }
 #  endif /* FLOATING POINT */
 png_uint_32 PNGAPI
-png_get_sCAL_s(png_structp png_ptr, png_infop info_ptr,
+png_get_sCAL_s(png_const_structp png_ptr, png_const_infop info_ptr,
    int *unit, png_charpp width, png_charpp height)
 {
   if (png_ptr != NULL && info_ptr != NULL &&
@@ -772,7 +779,7 @@ png_get_sCAL_s(png_structp png_ptr, png_infop info_ptr,

 #ifdef PNG_pHYs_SUPPORTED
 png_uint_32 PNGAPI
-png_get_pHYs(png_structp png_ptr, png_infop info_ptr,
+png_get_pHYs(png_const_structp png_ptr, png_const_infop info_ptr,
    png_uint_32 *res_x, png_uint_32 *res_y, int *unit_type)
 {
   png_uint_32 retval = 0;
@@ -806,8 +813,8 @@ png_get_pHYs(png_structp png_ptr, png_infop info_ptr,
 #endif /* pHYs */

 png_uint_32 PNGAPI
-png_get_PLTE(png_structp png_ptr, png_infop info_ptr, png_colorp *palette,
-    int *num_palette)
+png_get_PLTE(png_const_structp png_ptr, png_const_infop info_ptr,
+    png_colorp *palette, int *num_palette)
 {
   png_debug1(1, "in %s retrieval function", "PLTE");

@@ -825,7 +832,8 @@ png_get_PLTE(png_structp png_ptr, png_infop info_ptr, png_colorp *palette,

 #ifdef PNG_sBIT_SUPPORTED
 png_uint_32 PNGAPI
-png_get_sBIT(png_structp png_ptr, png_infop info_ptr, png_color_8p *sig_bit)
+png_get_sBIT(png_const_structp png_ptr, png_infop info_ptr,
+    png_color_8p *sig_bit)
 {
   png_debug1(1, "in %s retrieval function", "sBIT");

@@ -842,8 +850,8 @@ png_get_sBIT(png_structp png_ptr, png_infop info_ptr, png_color_8p *sig_bit)

 #ifdef PNG_TEXT_SUPPORTED
 png_uint_32 PNGAPI
-png_get_text(png_structp png_ptr, png_infop info_ptr, png_textp *text_ptr,
-    int *num_text)
+png_get_text(png_const_structp png_ptr, png_const_infop info_ptr,
+    png_textp *text_ptr, int *num_text)
 {
   if (png_ptr != NULL && info_ptr != NULL && info_ptr->num_text > 0)
   {
@@ -869,7 +877,7 @@ png_get_text(png_structp png_ptr, png_infop info_ptr, png_textp *text_ptr,

 #ifdef PNG_tIME_SUPPORTED
 png_uint_32 PNGAPI
-png_get_tIME(png_structp png_ptr, png_infop info_ptr, png_timep *mod_time)
+png_get_tIME(png_const_structp png_ptr, png_infop info_ptr, png_timep *mod_time)
 {
   png_debug1(1, "in %s retrieval function", "tIME");

@@ -886,7 +894,7 @@ png_get_tIME(png_structp png_ptr, png_infop info_ptr, png_timep *mod_time)

 #ifdef PNG_tRNS_SUPPORTED
 png_uint_32 PNGAPI
-png_get_tRNS(png_structp png_ptr, png_infop info_ptr,
+png_get_tRNS(png_const_structp png_ptr, png_infop info_ptr,
    png_bytep *trans_alpha, int *num_trans, png_color_16p *trans_color)
 {
   png_uint_32 retval = 0;
@@ -931,7 +939,7 @@ png_get_tRNS(png_structp png_ptr, png_infop info_ptr,

 #ifdef PNG_UNKNOWN_CHUNKS_SUPPORTED
 int PNGAPI
-png_get_unknown_chunks(png_structp png_ptr, png_infop info_ptr,
+png_get_unknown_chunks(png_const_structp png_ptr, png_const_infop info_ptr,
    png_unknown_chunkpp unknowns)
 {
   if (png_ptr != NULL && info_ptr != NULL && unknowns != NULL)
@@ -946,7 +954,7 @@ png_get_unknown_chunks(png_structp png_ptr, png_infop info_ptr,

 #ifdef PNG_READ_RGB_TO_GRAY_SUPPORTED
 png_byte PNGAPI
-png_get_rgb_to_gray_status (png_structp png_ptr)
+png_get_rgb_to_gray_status (png_const_structp png_ptr)
 {
   return (png_byte)(png_ptr ? png_ptr->rgb_to_gray_status : 0);
 }
@@ -954,14 +962,14 @@ png_get_rgb_to_gray_status (png_structp png_ptr)

 #ifdef PNG_USER_CHUNKS_SUPPORTED
 png_voidp PNGAPI
-png_get_user_chunk_ptr(png_structp png_ptr)
+png_get_user_chunk_ptr(png_const_structp png_ptr)
 {
   return (png_ptr ? png_ptr->user_chunk_ptr : NULL);
 }
 #endif

 png_size_t PNGAPI
-png_get_compression_buffer_size(png_structp png_ptr)
+png_get_compression_buffer_size(png_const_structp png_ptr)
 {
   return (png_ptr ? png_ptr->zbuf_size : 0L);
 }
@@ -971,27 +979,27 @@ png_get_compression_buffer_size(png_structp png_ptr)
 /* These functions were added to libpng 1.2.6 and were enabled
 * by default in libpng-1.4.0 */
 png_uint_32 PNGAPI
-png_get_user_width_max (png_structp png_ptr)
+png_get_user_width_max (png_const_structp png_ptr)
 {
   return (png_ptr ? png_ptr->user_width_max : 0);
 }

 png_uint_32 PNGAPI
-png_get_user_height_max (png_structp png_ptr)
+png_get_user_height_max (png_const_structp png_ptr)
 {
   return (png_ptr ? png_ptr->user_height_max : 0);
 }

 /* This function was added to libpng 1.4.0 */
 png_uint_32 PNGAPI
-png_get_chunk_cache_max (png_structp png_ptr)
+png_get_chunk_cache_max (png_const_structp png_ptr)
 {
   return (png_ptr ? png_ptr->user_chunk_cache_max : 0);
 }

 /* This function was added to libpng 1.4.1 */
 png_alloc_size_t PNGAPI
-png_get_chunk_malloc_max (png_structp png_ptr)
+png_get_chunk_malloc_max (png_const_structp png_ptr)
 {
   return (png_ptr ? png_ptr->user_chunk_malloc_max : 0);
 }
@@ -1005,6 +1013,15 @@ png_get_io_state (png_structp png_ptr)
   return png_ptr->io_state;
 }

+png_uint_32 PNGAPI
+png_get_io_chunk_type (png_const_structp png_ptr)
+{
+   return ((png_ptr->chunk_name[0] << 24) +
+           (png_ptr->chunk_name[1] << 16) +
+           (png_ptr->chunk_name[2] <<  8) +
+           (png_ptr->chunk_name[3]));
+}
+
 png_const_bytep PNGAPI
 png_get_io_chunk_name (png_structp png_ptr)
 {
--- a/pnginfo.h
+++ b/pnginfo.h
@@ -1,11 +1,11 @@

 /* pnginfo.h - header file for PNG reference library
 *
- * Copyright (c) 1998-2010 Glenn Randers-Pehrson
+ * Copyright (c) 1998-2011 Glenn Randers-Pehrson
 * (Version 0.96 Copyright (c) 1996, 1997 Andreas Dilger)
 * (Version 0.88 Copyright (c) 1995, 1996 Guy Eric Schalnat, Group 42, Inc.)
 *
- * Last changed in libpng version 1.5.0 - (PENDING RELEASE)
+ * Last changed in libpng 1.5.0 [January 6, 2011]
 *
 * This code is released under the libpng license.
 * For conditions of distribution and use, see the disclaimer
--- a/pngmem.c
+++ b/pngmem.c
@@ -1,8 +1,8 @@

 /* pngmem.c - stub functions for memory allocation
 *
- * Last changed in libpng 1.5.0 [(PENDING RELEASE)]
- * Copyright (c) 1998-2010 Glenn Randers-Pehrson
+ * Last changed in libpng 1.5.1 [February 3, 2011]
+ * Copyright (c) 1998-2011 Glenn Randers-Pehrson
 * (Version 0.96 Copyright (c) 1996, 1997 Andreas Dilger)
 * (Version 0.88 Copyright (c) 1995, 1996 Guy Eric Schalnat, Group 42, Inc.)
 *
@@ -647,7 +647,7 @@ png_set_mem_fn(png_structp png_ptr, png_voidp mem_ptr, png_malloc_ptr
 * pointer before png_write_destroy and png_read_destroy are called.
 */
 png_voidp PNGAPI
-png_get_mem_ptr(png_structp png_ptr)
+png_get_mem_ptr(png_const_structp png_ptr)
 {
   if (png_ptr == NULL)
      return (NULL);
--- a/pngpread.c
+++ b/pngpread.c
@@ -1,8 +1,8 @@

 /* pngpread.c - read a png file in push mode
 *
- * Last changed in libpng 1.5.0 [(PENDING RELEASE)]
- * Copyright (c) 1998-2010 Glenn Randers-Pehrson
+ * Last changed in libpng 1.5.2 [(PENDING RELEASE)]
+ * Copyright (c) 1998-2011 Glenn Randers-Pehrson
 * (Version 0.96 Copyright (c) 1996, 1997 Andreas Dilger)
 * (Version 0.88 Copyright (c) 1995, 1996 Guy Eric Schalnat, Group 42, Inc.)
 *
@@ -41,6 +41,64 @@ png_process_data(png_structp png_ptr, png_infop info_ptr,
   }
 }

+png_size_t PNGAPI
+png_process_data_pause(png_structp png_ptr, int save)
+{
+   if (png_ptr != NULL)
+   {
+      /* It's easiest for the caller if we do the save, then the caller doesn't
+       * have to supply the same data again:
+       */
+      if (save)
+         png_push_save_buffer(png_ptr);
+      else
+      {
+         /* This includes any pending saved bytes: */
+         png_size_t remaining = png_ptr->buffer_size;
+         png_ptr->buffer_size = 0;
+
+         /* So subtract the saved buffer size, unless all the data
+          * is actually 'saved', in which case we just return 0
+          */
+         if (png_ptr->save_buffer_size < remaining)
+            return remaining - png_ptr->save_buffer_size;
+      }
+   }
+
+   return 0;
+}
+
+png_uint_32 PNGAPI
+png_process_data_skip(png_structp png_ptr)
+{
+   png_uint_32 remaining = 0;
+
+   if (png_ptr != NULL && png_ptr->process_mode == PNG_SKIP_MODE &&
+      png_ptr->skip_length > 0)
+   {
+      /* At the end of png_process_data the buffer size must be 0 (see the loop
+       * above) so we can detect a broken call here:
+       */
+      if (png_ptr->buffer_size != 0)
+         png_error(png_ptr,
+            "png_process_data_skip called inside png_process_data");
+
+      /* If is impossible for there to be a saved buffer at this point -
+       * otherwise we could not be in SKIP mode.  This will also happen if
+       * png_process_skip is called inside png_process_data (but only very
+       * rarely.)
+       */
+      if (png_ptr->save_buffer_size != 0)
+         png_error(png_ptr, "png_process_data_skip called with saved data");
+
+      remaining = png_ptr->skip_length;
+      png_ptr->skip_length = 0;
+      png_ptr->process_mode = PNG_READ_CHUNK_MODE;
+   }
+
+   return remaining;
+}
+
 /* What we do with the incoming data depends on what we were previously
 * doing before we ran out of data...
 */
@@ -582,10 +640,10 @@ png_push_crc_finish(png_structp png_ptr)
 {
   if (png_ptr->skip_length && png_ptr->save_buffer_size)
   {
-      png_size_t save_size = png_ptr->current_buffer_size;
+      png_size_t save_size = png_ptr->save_buffer_size;
      png_uint_32 skip_length = png_ptr->skip_length;

-      /* We want the smaller of 'skip_length' and 'current_buffer_size', but
+      /* We want the smaller of 'skip_length' and 'save_buffer_size', but
       * they are of different types and we don't know which variable has the
       * fewest bits.  Carefully select the smaller and cast it to the type of
       * the larger - this cannot overflow.  Do not cast in the following test
@@ -609,10 +667,8 @@ png_push_crc_finish(png_structp png_ptr)
      png_size_t save_size = png_ptr->current_buffer_size;
      png_uint_32 skip_length = png_ptr->skip_length;

-      /* We want the smaller of 'skip_length' and 'current_buffer_size', but
-       * they are of different types and we don't know which variable has the
-       * fewest bits.  Carefully select the smaller and cast it to the type of
-       * the larger - this cannot overflow.
+      /* We want the smaller of 'skip_length' and 'current_buffer_size', here,
+       * the same problem exists as above and the same solution.
       */
      if (skip_length < save_size)
         save_size = (png_size_t)skip_length;
@@ -970,7 +1026,7 @@ png_push_process_row(png_structp png_ptr)

   png_memcpy(png_ptr->prev_row, png_ptr->row_buf, png_ptr->rowbytes + 1);

-   if (png_ptr->transformations || (png_ptr->flags&PNG_FLAG_STRIP_ALPHA))
+   if (png_ptr->transformations)
      png_do_read_transformations(png_ptr);

 #ifdef PNG_READ_INTERLACING_SUPPORTED
@@ -1230,7 +1286,7 @@ png_push_handle_tEXt(png_structp png_ptr, png_infop info_ptr, png_uint_32
 {
   if (!(png_ptr->mode & PNG_HAVE_IHDR) || (png_ptr->mode & PNG_HAVE_IEND))
      {
-         info_ptr = info_ptr; /* To quiet some compiler warnings */
+         PNG_UNUSED(info_ptr) /* To quiet some compiler warnings */
         png_error(png_ptr, "Out of place tEXt");
         /*NOT REACHED*/
      }
@@ -1327,7 +1383,7 @@ png_push_handle_zTXt(png_structp png_ptr, png_infop info_ptr, png_uint_32
 {
   if (!(png_ptr->mode & PNG_HAVE_IHDR) || (png_ptr->mode & PNG_HAVE_IEND))
   {
-      info_ptr = info_ptr; /* To quiet some compiler warnings */
+      PNG_UNUSED(info_ptr) /* To quiet some compiler warnings */
      png_error(png_ptr, "Out of place zTXt");
      /*NOT REACHED*/
   }
@@ -1531,7 +1587,7 @@ png_push_handle_iTXt(png_structp png_ptr, png_infop info_ptr, png_uint_32
 {
   if (!(png_ptr->mode & PNG_HAVE_IHDR) || (png_ptr->mode & PNG_HAVE_IEND))
   {
-      info_ptr = info_ptr; /* To quiet some compiler warnings */
+      PNG_UNUSED(info_ptr) /* To quiet some compiler warnings */
      png_error(png_ptr, "Out of place iTXt");
      /*NOT REACHED*/
   }
@@ -1669,7 +1725,7 @@ png_push_handle_unknown(png_structp png_ptr, png_infop info_ptr, png_uint_32
 #endif
         png_chunk_error(png_ptr, "unknown critical chunk");

-      info_ptr = info_ptr; /* To quiet some compiler warnings */
+      PNG_UNUSED(info_ptr) /* To quiet some compiler warnings */
   }

 #ifdef PNG_READ_UNKNOWN_CHUNKS_SUPPORTED
@@ -1788,7 +1844,7 @@ png_set_progressive_read_fn(png_structp png_ptr, png_voidp progressive_ptr,
 }

 png_voidp PNGAPI
-png_get_progressive_ptr(png_structp png_ptr)
+png_get_progressive_ptr(png_const_structp png_ptr)
 {
   if (png_ptr == NULL)
      return (NULL);
--- a/pngpriv.h
+++ b/pngpriv.h
@@ -1,12 +1,13 @@

 /* pngpriv.h - private declarations for use inside libpng
 *
- * libpng version 1.5.0beta55 - (PENDING RELEASE)
 * For conditions of distribution and use, see copyright notice in png.h
- * Copyright (c) 1998-2010 Glenn Randers-Pehrson
+ * Copyright (c) 1998-2011 Glenn Randers-Pehrson
 * (Version 0.96 Copyright (c) 1996, 1997 Andreas Dilger)
 * (Version 0.88 Copyright (c) 1995, 1996 Guy Eric Schalnat, Group 42, Inc.)
 *
+ * Last changed in libpng 1.5.2 [(PENDING RELEASE)]
+ *
 * This code is released under the libpng license.
 * For conditions of distribution and use, see the disclaimer
 * and license in png.h
@@ -63,9 +64,10 @@ typedef PNG_CONST png_uint_16p FAR * png_const_uint_16pp;
 #endif

 /* Moved to pngpriv.h at libpng-1.5.0 */
-/* NOTE: some of these may be used in external applications as these definitions
- * were exposed in pngconf.h prior to 1.5.
+/* NOTE: some of these may have been used in external applications as
+ * these definitions were exposed in pngconf.h prior to 1.5.
 */
+
 /* If you are running on a machine where you cannot allocate more
 * than 64K of memory at once, uncomment this.  While libpng will not
 * normally need that much memory in a chunk (unless you load up a very
@@ -81,6 +83,16 @@ typedef PNG_CONST png_uint_16p FAR * png_const_uint_16pp;
 #  define PNG_MAX_MALLOC_64K
 #endif

+#ifndef PNG_UNUSED
+/* Unused formal parameter warnings are silenced using the following macro
+ * which is expected to have no bad effects on performance (optimizing
+ * compilers will probably remove it entirely).  Note that if you replace
+ * it with something other than whitespace, you must include the terminating
+ * semicolon.
+ */
+#  define PNG_UNUSED(param) (void)param;
+#endif
+
 /* Just a little check that someone hasn't tried to define something
 * contradictory.
 */
@@ -107,7 +119,7 @@ typedef PNG_CONST png_uint_16p FAR * png_const_uint_16pp;
 * aren't usually used outside the library (as far as I know), so it is
 * debatable if they should be exported at all.  In the future, when it
 * is possible to have run-time registry of chunk-handling functions,
- * some of these will be made available again.
+ * some of these might be made available again.
 #  define PNG_EXTERN extern
 */
 #  define PNG_EXTERN
@@ -130,7 +142,7 @@ typedef PNG_CONST png_uint_16p FAR * png_const_uint_16pp;
    defined(PNG_FLOATING_ARITHMETIC_SUPPORTED)
   /* png.c requires the following ANSI-C constants if the conversion of
    * floating point to ASCII is implemented therein:
-    * 
+    *
    *  DBL_DIG  Maximum number of decimal digits (can be set to any constant)
    *  DBL_MIN  Smallest normalized fp number (can be set to an arbitrary value)
    *  DBL_MAX  Maximum floating point number (can be set to an arbitrary value)
@@ -247,6 +259,7 @@ typedef PNG_CONST png_uint_16p FAR * png_const_uint_16pp;
 /* CONSTANTS and UTILITY MACROS
 * These are used internally by libpng and not exposed in the API
 */
+
 /* Various modes of operation.  Note that after an init, mode is set to
 * zero automatically when the structure is created.
 */
@@ -275,7 +288,7 @@ typedef PNG_CONST png_uint_16p FAR * png_const_uint_16pp;
 #define PNG_QUANTIZE            0x0040
 #define PNG_BACKGROUND          0x0080
 #define PNG_BACKGROUND_EXPAND   0x0100
-                          /*    0x0200 unused */
+#define PNG_EXPAND_16           0x0200     /* Added to libpng 1.5.2 */
 #define PNG_16_TO_8             0x0400
 #define PNG_RGBA                0x0800
 #define PNG_EXPAND              0x1000
@@ -329,8 +342,8 @@ typedef PNG_CONST png_uint_16p FAR * png_const_uint_16pp;
 #define PNG_FLAG_STRIP_ERROR_NUMBERS      0x40000L
 #define PNG_FLAG_STRIP_ERROR_TEXT         0x80000L
 #define PNG_FLAG_MALLOC_NULL_MEM_OK       0x100000L
-#define PNG_FLAG_ADD_ALPHA                0x200000L  /* Added to libpng-1.2.8 */
-#define PNG_FLAG_STRIP_ALPHA              0x400000L  /* Added to libpng-1.2.8 */
+                                  /*      0x200000L  unused */
+                                  /*      0x400000L  unused */
 #define PNG_FLAG_BENIGN_ERRORS_WARN       0x800000L  /* Added to libpng-1.4.0 */
                                  /*     0x1000000L  unused */
                                  /*     0x2000000L  unused */
@@ -399,8 +412,9 @@ typedef PNG_CONST png_uint_16p FAR * png_const_uint_16pp;
 * its argument multiple times, so must be used with care.  The
 * range checking uses the PNG specification values for a signed
 * 32 bit fixed point value except that the values are deliberately
- * rounded-to-zero to an integral value - 21474.  's' is a string
- * that describes the value being converted.
+ * rounded-to-zero to an integral value - 21474 (21474.83 is roughly
+ * (2^31-1) * 100000). 's' is a string that describes the value being
+ * converted.
 *
 * NOTE: this macro will raise a png_error if the range check fails,
 * therefore it is normally only appropriate to use this on values
@@ -760,8 +774,8 @@ PNG_EXTERN void png_do_write_invert_alpha PNGARG((png_row_infop row_info,

 #if defined(PNG_WRITE_FILLER_SUPPORTED) || \
    defined(PNG_READ_STRIP_ALPHA_SUPPORTED)
-PNG_EXTERN void png_do_strip_filler PNGARG((png_row_infop row_info,
-    png_bytep row, png_uint_32 flags));
+PNG_EXTERN void png_do_strip_channel PNGARG((png_row_infop row_info,
+    png_bytep row, int at_start));
 #endif

 #ifdef PNG_16BIT_SUPPORTED
@@ -863,6 +877,11 @@ PNG_EXTERN void png_do_expand PNGARG((png_row_infop row_info,
    png_bytep row, png_const_color_16p trans_color));
 #endif

+#ifdef PNG_READ_EXPAND_16_SUPPORTED
+PNG_EXTERN void png_do_expand_16 PNGARG((png_row_infop row_info,
+    png_bytep row));
+#endif
+
 /* The following decodes the appropriate chunks, and does error correction,
 * then calls the appropriate callback for the chunk if it is valid.
 */
@@ -1172,13 +1191,13 @@ PNG_EXTERN int png_check_fp_string PNGARG((png_const_charp string,
 * holds the result.
 */
 PNG_EXTERN int png_muldiv PNGARG((png_fixed_point_p res, png_fixed_point a,
-    png_int_32 times, png_int_32 div));
+    png_int_32 multiplied_by, png_int_32 divided_by));
 #endif

 #if defined(PNG_READ_GAMMA_SUPPORTED) || defined(PNG_INCH_CONVERSIONS_SUPPORTED)
 /* Same deal, but issue a warning on overflow and return 0. */
 PNG_EXTERN png_fixed_point png_muldiv_warn PNGARG((png_structp png_ptr,
-    png_fixed_point a, png_int_32 times, png_int_32 div));
+    png_fixed_point a, png_int_32 multiplied_by, png_int_32 divided_by));
 #endif

 #ifdef PNG_READ_GAMMA_SUPPORTED
@@ -1205,12 +1224,12 @@ PNG_EXTERN png_fixed_point png_reciprocal2 PNGARG((png_fixed_point a,
 * correct bit value - 0..255 or 0..65535 as required.
 */
 PNG_EXTERN png_uint_16 png_gamma_correct PNGARG((png_structp png_ptr,
-    unsigned int value, png_fixed_point gamma));
-PNG_EXTERN int png_gamma_significant PNGARG((png_fixed_point gamma));
+    unsigned int value, png_fixed_point gamma_value));
+PNG_EXTERN int png_gamma_significant PNGARG((png_fixed_point gamma_value));
 PNG_EXTERN png_uint_16 png_gamma_16bit_correct PNGARG((unsigned int value,
-    png_fixed_point gamma));
+    png_fixed_point gamma_value));
 PNG_EXTERN png_byte png_gamma_8bit_correct PNGARG((unsigned int value,
-    png_fixed_point gamma));
+    png_fixed_point gamma_value));
 PNG_EXTERN void png_build_gamma_table PNGARG((png_structp png_ptr,
    int bit_depth));
 #endif
--- a/pngread.c
+++ b/pngread.c
@@ -1,8 +1,8 @@

 /* pngread.c - read a PNG file
 *
- * Last changed in libpng 1.5.0 [(PENDING RELEASE)]
- * Copyright (c) 1998-2010 Glenn Randers-Pehrson
+ * Last changed in libpng 1.5.2 [(PENDING RELEASE)]
+ * Copyright (c) 1998-2011 Glenn Randers-Pehrson
 * (Version 0.96 Copyright (c) 1996, 1997 Andreas Dilger)
 * (Version 0.88 Copyright (c) 1995, 1996 Guy Eric Schalnat, Group 42, Inc.)
 *
@@ -488,9 +488,11 @@ void PNGAPI
 png_read_row(png_structp png_ptr, png_bytep row, png_bytep dsp_row)
 {
   PNG_IDAT;
+#ifdef PNG_READ_INTERLACING_SUPPORTED
   PNG_CONST int png_pass_dsp_mask[7] = {0xff, 0x0f, 0xff, 0x33, 0xff, 0x55,
       0xff};
   PNG_CONST int png_pass_mask[7] = {0x80, 0x08, 0x88, 0x22, 0xaa, 0x55, 0xff};
+#endif
   int ret;

   if (png_ptr == NULL)
@@ -702,7 +704,7 @@ png_read_row(png_structp png_ptr, png_bytep row, png_bytep dsp_row)
 #endif


-   if (png_ptr->transformations || (png_ptr->flags&PNG_FLAG_STRIP_ALPHA))
+   if (png_ptr->transformations)
      png_do_read_transformations(png_ptr);

 #ifdef PNG_READ_INTERLACING_SUPPORTED
@@ -841,7 +843,7 @@ png_read_image(png_structp png_ptr, png_bytepp image)
   }
   else
   {
-      if (!(png_ptr->transformations & PNG_INTERLACE))
+      if (png_ptr->interlaced && !(png_ptr->transformations & PNG_INTERLACE))
      {
         /* Caller called png_start_read_image or png_read_update_info without
          * first turning on the PNG_INTERLACE transform.  We can fix this here,
@@ -1311,7 +1313,7 @@ png_read_png(png_structp png_ptr, png_infop info_ptr,
 {
   int row;

-   if (png_ptr == NULL)
+   if (png_ptr == NULL || info_ptr == NULL)
      return;

   /* png_read_info() gives us all of the information from the
@@ -1426,6 +1428,11 @@ png_read_png(png_structp png_ptr, png_infop info_ptr,

   /* We don't handle adding filler bytes */

+   /* We use png_read_image and rely on that for interlace handling, but we also
+    * call png_read_update_info therefore must turn on interlace handling now:
+    */
+   (void)png_set_interlace_handling(png_ptr);
+
   /* Optional call to gamma correct and add the background to the palette
    * and update info structure.  REQUIRED if you are expecting libpng to
    * update the palette for you (i.e., you selected such a transform above).
@@ -1457,8 +1464,8 @@ png_read_png(png_structp png_ptr, png_infop info_ptr,
   /* Read rest of file, and get additional chunks in info_ptr - REQUIRED */
   png_read_end(png_ptr, info_ptr);

-   transforms = transforms; /* Quiet compiler warnings */
-   params = params;
+   PNG_UNUSED(transforms)   /* Quiet compiler warnings */
+   PNG_UNUSED(params)

 }
 #endif /* PNG_INFO_IMAGE_SUPPORTED */
--- a/pngrio.c
+++ b/pngrio.c
@@ -1,8 +1,8 @@

 /* pngrio.c - functions for data input
 *
- * Last changed in libpng 1.5.0 [(PENDING RELEASE)]
- * Copyright (c) 1998-2010 Glenn Randers-Pehrson
+ * Last changed in libpng 1.5.0 [January 6, 2011]
+ * Copyright (c) 1998-2011 Glenn Randers-Pehrson
 * (Version 0.96 Copyright (c) 1996, 1997 Andreas Dilger)
 * (Version 0.88 Copyright (c) 1995, 1996 Guy Eric Schalnat, Group 42, Inc.)
 *
--- a/pngrtran.c
+++ b/pngrtran.c
@@ -1,8 +1,8 @@

 /* pngrtran.c - transforms the data in a row for PNG readers
 *
- * Last changed in libpng 1.5.0 [(PENDING RELEASE)]
- * Copyright (c) 1998-2010 Glenn Randers-Pehrson
+ * Last changed in libpng 1.5.2 [(PENDING RELEASE)]
+ * Copyright (c) 1998-2011 Glenn Randers-Pehrson
 * (Version 0.96 Copyright (c) 1996, 1997 Andreas Dilger)
 * (Version 0.88 Copyright (c) 1995, 1996 Guy Eric Schalnat, Group 42, Inc.)
 *
@@ -137,6 +137,7 @@ png_set_strip_16(png_structp png_ptr)
      return;

   png_ptr->transformations |= PNG_16_TO_8;
+   png_ptr->transformations &= ~PNG_EXPAND_16;
 }
 #endif

@@ -149,7 +150,7 @@ png_set_strip_alpha(png_structp png_ptr)
   if (png_ptr == NULL)
      return;

-   png_ptr->flags |= PNG_FLAG_STRIP_ALPHA;
+   png_ptr->transformations |= PNG_STRIP_ALPHA;
 }
 #endif

@@ -686,14 +687,38 @@ png_set_tRNS_to_alpha(png_structp png_ptr)
 }
 #endif /* defined(PNG_READ_EXPAND_SUPPORTED) */

+#ifdef PNG_READ_EXPAND_16_SUPPORTED
+/* Expand to 16 bit channels, expand the tRNS chunk too (because otherwise
+ * it may not work correctly.)
+ */
+void PNGAPI
+png_set_expand_16(png_structp png_ptr)
+{
+   png_debug(1, "in png_set_expand_16");
+
+   if (png_ptr == NULL)
+      return;
+
+   png_ptr->transformations |= (PNG_EXPAND_16 | PNG_EXPAND | PNG_EXPAND_tRNS);
+   png_ptr->transformations &= ~PNG_16_TO_8;
+
+   png_ptr->flags &= ~PNG_FLAG_ROW_INIT;
+}
+#endif
+
 #ifdef PNG_READ_GRAY_TO_RGB_SUPPORTED
 void PNGAPI
 png_set_gray_to_rgb(png_structp png_ptr)
 {
   png_debug(1, "in png_set_gray_to_rgb");

-   png_ptr->transformations |= PNG_GRAY_TO_RGB;
-   png_ptr->flags &= ~PNG_FLAG_ROW_INIT;
+   if (png_ptr != NULL)
+   {
+      /* Because rgb must be 8 bits or more: */
+      png_set_expand_gray_1_2_4_to_8(png_ptr);
+      png_ptr->transformations |= PNG_GRAY_TO_RGB;
+      png_ptr->flags &= ~PNG_FLAG_ROW_INIT;
+   }
 }
 #endif

@@ -1280,6 +1305,14 @@ png_read_transform_info(png_structp png_ptr, png_infop info_ptr)
   }
 #endif

+#ifdef PNG_READ_EXPAND_16_SUPPORTED
+   if (png_ptr->transformations & PNG_EXPAND_16 && info_ptr->bit_depth == 8 &&
+      info_ptr->color_type != PNG_COLOR_TYPE_PALETTE)
+   {
+      info_ptr->bit_depth = 16;
+   }
+#endif
+
 #ifdef PNG_READ_BACKGROUND_SUPPORTED
   if (png_ptr->transformations & PNG_BACKGROUND)
   {
@@ -1348,7 +1381,7 @@ png_read_transform_info(png_structp png_ptr, png_infop info_ptr)
      info_ptr->channels = 1;

 #ifdef PNG_READ_STRIP_ALPHA_SUPPORTED
-   if (png_ptr->flags & PNG_FLAG_STRIP_ALPHA)
+   if (png_ptr->transformations & PNG_STRIP_ALPHA)
      info_ptr->color_type &= ~PNG_COLOR_MASK_ALPHA;
 #endif

@@ -1434,24 +1467,31 @@ png_do_read_transformations(png_structp png_ptr)
         png_do_expand_palette(&(png_ptr->row_info), png_ptr->row_buf + 1,
             png_ptr->palette, png_ptr->trans_alpha, png_ptr->num_trans);
      }
+
      else
      {
         if (png_ptr->num_trans &&
             (png_ptr->transformations & PNG_EXPAND_tRNS))
            png_do_expand(&(png_ptr->row_info), png_ptr->row_buf + 1,
                &(png_ptr->trans_color));
-         else

+         else
            png_do_expand(&(png_ptr->row_info), png_ptr->row_buf + 1,
                NULL);
      }
   }
 #endif

+   /* Delay the 'expand 16' step until later for efficiency, so that the
+    * intermediate steps work with 8 bit data.
+    */
+
 #ifdef PNG_READ_STRIP_ALPHA_SUPPORTED
-   if (png_ptr->flags & PNG_FLAG_STRIP_ALPHA)
-      png_do_strip_filler(&(png_ptr->row_info), png_ptr->row_buf + 1,
-          PNG_FLAG_FILLER_AFTER | (png_ptr->flags & PNG_FLAG_STRIP_ALPHA));
+   if ((png_ptr->transformations & PNG_STRIP_ALPHA) &&
+      (png_ptr->row_info.color_type == PNG_COLOR_TYPE_RGB_ALPHA ||
+      png_ptr->row_info.color_type == PNG_COLOR_TYPE_GRAY_ALPHA))
+      png_do_strip_channel(&(png_ptr->row_info), png_ptr->row_buf + 1,
+         0/*!at_start, because SWAP_ALPHA happens later*/);
 #endif

 #ifdef PNG_READ_RGB_TO_GRAY_SUPPORTED
@@ -1560,6 +1600,16 @@ png_do_read_transformations(png_structp png_ptr)
   }
 #endif /* PNG_READ_QUANTIZE_SUPPORTED */

+#ifdef PNG_READ_EXPAND_16_SUPPORTED
+   /* Do the expansion now, after all the arithmetic has been done.  Notice
+    * that previous transformations can handle the PNG_EXPAND_16 flag if this
+    * is efficient (particularly true in the case of gamma correction, where
+    * better accuracy results faster!)
+    */
+   if (png_ptr->transformations & PNG_EXPAND_16)
+      png_do_expand_16(&png_ptr->row_info, png_ptr->row_buf + 1);
+#endif
+
 #ifdef PNG_READ_INVERT_SUPPORTED
   if (png_ptr->transformations & PNG_INVERT_MONO)
      png_do_invert(&(png_ptr->row_info), png_ptr->row_buf + 1);
@@ -1587,6 +1637,9 @@ png_do_read_transformations(png_structp png_ptr)
 #endif

 #ifdef PNG_READ_GRAY_TO_RGB_SUPPORTED
+   /*NOTE: this must be in the wrong place - what happens if BGR is set too?
+    * Need pngvalid to test this combo.
+    */
   /* If gray -> RGB, do so now only if we did not do so above */
   if ((png_ptr->transformations & PNG_GRAY_TO_RGB) &&
       (png_ptr->mode & PNG_BACKGROUND_IS_GRAY))
@@ -1799,7 +1852,7 @@ png_do_unshift(png_row_infop row_info, png_bytep row,
      switch (row_info->bit_depth)
      {
         default:
-            break; 
+            break;

         case 2:
         {
@@ -2427,7 +2480,7 @@ png_do_rgb_to_gray(png_structp png_ptr, png_row_infop row_info, png_bytep row)

   png_debug(1, "in png_do_rgb_to_gray");

-   if (
+   if (!(row_info->color_type & PNG_COLOR_MASK_PALETTE) &&
       (row_info->color_type & PNG_COLOR_MASK_COLOR))
   {
      png_uint_32 rc = png_ptr->rgb_to_gray_red_coeff;
@@ -3778,7 +3831,7 @@ png_do_expand_palette(png_row_infop row_info, png_bytep row,
         row_info->rowbytes = row_width;
      }

-      else if (row_info->bit_depth == 8)
+      if (row_info->bit_depth == 8)
      {
         {
            if (trans_alpha != NULL)
@@ -4059,6 +4112,37 @@ png_do_expand(png_row_infop row_info, png_bytep row,
 }
 #endif

+#ifdef PNG_READ_EXPAND_16_SUPPORTED
+/* If the bit depth is 8 and the colour type is not a palette type expand the
+ * whole row to 16 bits.  Has no effect otherwise.
+ */
+void /* PRIVATE */
+png_do_expand_16(png_row_infop row_info, png_bytep row)
+{
+   if (row_info->bit_depth == 8 &&
+      row_info->color_type != PNG_COLOR_TYPE_PALETTE)
+   {
+      /* The row have a sequence of bytes containing [0..255] and we need
+       * to turn it into another row containing [0..65535], to do this we
+       * calculate:
+       *
+       *  (input / 255) * 65535
+       *
+       *  Which happens to be exactly input * 257 and this can be achieved
+       *  simply by byte replication in place (copying backwards).
+       */
+      png_byte *sp = row + row_info->rowbytes; /* source, last byte + 1 */
+      png_byte *dp = sp + row_info->rowbytes;  /* destination, end + 1 */
+      while (dp > sp)
+         dp[-2] = dp[-1] = *--sp, dp -= 2;
+
+      row_info->rowbytes *= 2;
+      row_info->bit_depth = 16;
+      row_info->pixel_depth = (png_byte)(row_info->channels * 16);
+   }
+}
+#endif
+
 #ifdef PNG_READ_QUANTIZE_SUPPORTED
 void /* PRIVATE */
 png_do_quantize(png_row_infop row_info, png_bytep row,
--- a/pngrutil.c
+++ b/pngrutil.c
@@ -1,8 +1,8 @@

 /* pngrutil.c - utilities to read a PNG file
 *
- * Last changed in libpng 1.5.0 [(PENDING RELEASE)]
- * Copyright (c) 1998-2010 Glenn Randers-Pehrson
+ * Last changed in libpng 1.5.2 [(PENDING RELEASE)]
+ * Copyright (c) 1998-2011 Glenn Randers-Pehrson
 * (Version 0.96 Copyright (c) 1996, 1997 Andreas Dilger)
 * (Version 0.88 Copyright (c) 1995, 1996 Guy Eric Schalnat, Group 42, Inc.)
 *
@@ -608,7 +608,7 @@ png_handle_IHDR(png_structp png_ptr, png_infop info_ptr, png_uint_32 length)
   png_ptr->rowbytes = PNG_ROWBYTES(png_ptr->pixel_depth, png_ptr->width);
   png_debug1(3, "bit_depth = %d", png_ptr->bit_depth);
   png_debug1(3, "channels = %d", png_ptr->channels);
-   png_debug1(3, "rowbytes = %u", png_ptr->rowbytes);
+   png_debug1(3, "rowbytes = %lu", (unsigned long)png_ptr->rowbytes);
   png_set_IHDR(png_ptr, info_ptr, width, height, bit_depth,
       color_type, interlace_type, compression_type, filter_type);
 }
@@ -781,7 +781,7 @@ png_handle_IEND(png_structp png_ptr, png_infop info_ptr, png_uint_32 length)

   png_crc_finish(png_ptr, length);

-   info_ptr = info_ptr; /* Quiet compiler warnings about unused info_ptr */
+   PNG_UNUSED(info_ptr) /* Quiet compiler warnings about unused info_ptr */
 }

 #ifdef PNG_READ_gAMA_SUPPORTED
@@ -1248,7 +1248,9 @@ png_handle_iCCP(png_structp png_ptr, png_infop info_ptr, png_uint_32 length)

         png_snprintf2(umsg, 80,
             "Ignoring iCCP chunk with declared size = %u "
-              "and actual length = %u", profile_size, profile_length);
+              "and actual length = %u",
+              (unsigned int) profile_size,
+              (unsigned int) profile_length);
         png_warning(png_ptr, umsg);
      }
 #else
@@ -1960,7 +1962,7 @@ png_handle_pCAL(png_structp png_ptr, png_infop info_ptr, png_uint_32 length)
 void /* PRIVATE */
 png_handle_sCAL(png_structp png_ptr, png_infop info_ptr, png_uint_32 length)
 {
-   png_size_t slength, index;
+   png_size_t slength, i;
   int state;

   png_debug(1, "in png_handle_sCAL");
@@ -2017,21 +2019,21 @@ png_handle_sCAL(png_structp png_ptr, png_infop info_ptr, png_uint_32 length)
   /* Validate the ASCII numbers, need two ASCII numbers separated by
    * a '\0' and they need to fit exactly in the chunk data.
    */
-   index = 0;
+   i = 0;
   state = 0;

   if (png_ptr->chunkdata[1] == 45 /* negative width */ ||
-       !png_check_fp_number(png_ptr->chunkdata, slength, &state, &index) ||
-       index >= slength || png_ptr->chunkdata[index++] != 0)
+       !png_check_fp_number(png_ptr->chunkdata, slength, &state, &i) ||
+       i >= slength || png_ptr->chunkdata[i++] != 0)
      png_warning(png_ptr, "Invalid sCAL chunk ignored: bad width format");

   else
   {
-      png_size_t heighti = index;
+      png_size_t heighti = i;

-      if (png_ptr->chunkdata[index] == 45 /* negative height */ ||
-          !png_check_fp_number(png_ptr->chunkdata, slength, &state, &index) ||
-          index != slength)
+      if (png_ptr->chunkdata[i] == 45 /* negative height */ ||
+          !png_check_fp_number(png_ptr->chunkdata, slength, &state, &i) ||
+          i != slength)
         png_warning(png_ptr, "Invalid sCAL chunk ignored: bad height format");

      else
@@ -2619,7 +2621,7 @@ png_handle_unknown(png_structp png_ptr, png_infop info_ptr, png_uint_32 length)
   png_crc_finish(png_ptr, skip);

 #ifndef PNG_READ_USER_CHUNKS_SUPPORTED
-   info_ptr = info_ptr; /* Quiet compiler warnings about unused info_ptr */
+   PNG_UNUSED(info_ptr) /* Quiet compiler warnings about unused info_ptr */
 #endif
 }

@@ -3110,7 +3112,7 @@ png_do_read_interlace(png_structp png_ptr)
      row_info->rowbytes = PNG_ROWBYTES(row_info->pixel_depth, final_width);
   }
 #ifndef PNG_READ_PACKSWAP_SUPPORTED
-   transformations = transformations; /* Silence compiler warning */
+   PNG_UNUSED(transformations)  /* Silence compiler warning */
 #endif
 }
 #endif /* PNG_READ_INTERLACING_SUPPORTED */
@@ -3293,15 +3295,12 @@ png_read_finish_row(png_structp png_ptr)
                png_pass_yinc[png_ptr->pass] - 1 -
                png_pass_ystart[png_ptr->pass]) /
                png_pass_yinc[png_ptr->pass];
-
-            if (!(png_ptr->num_rows))
-               continue;
         }

         else  /* if (png_ptr->transformations & PNG_INTERLACE) */
-            break;
+            break; /* libpng deinterlacing sees every row */

-      } while (png_ptr->iwidth == 0);
+      } while (png_ptr->num_rows == 0 || png_ptr->iwidth == 0);

      if (png_ptr->pass < 7)
         return;
@@ -3464,6 +3463,24 @@ png_read_start_row(png_structp png_ptr)
   }
 #endif

+#ifdef PNG_READ_EXPAND_16_SUPPORTED
+   if (png_ptr->transformations & PNG_EXPAND_16)
+   {
+#     ifdef PNG_READ_EXPAND_SUPPORTED
+         /* In fact it is an error if it isn't supported, but checking is
+          * the safe way.
+          */
+         if (png_ptr->transformations & PNG_EXPAND)
+         {
+            if (png_ptr->bit_depth < 16)
+               max_pixel_depth *= 2;
+         }
+         else
+#     endif
+         png_ptr->transformations &= ~PNG_EXPAND_16;
+   }
+#endif
+
 #ifdef PNG_READ_FILLER_SUPPORTED
   if (png_ptr->transformations & (PNG_FILLER))
   {
@@ -3608,61 +3625,10 @@ defined(PNG_USER_TRANSFORM_PTR_SUPPORTED)
   png_debug1(3, "height = %u,", png_ptr->height);
   png_debug1(3, "iwidth = %u,", png_ptr->iwidth);
   png_debug1(3, "num_rows = %u,", png_ptr->num_rows);
-   png_debug1(3, "rowbytes = %u,", png_ptr->rowbytes);
-   png_debug1(3, "irowbytes = %u",
-       PNG_ROWBYTES(png_ptr->pixel_depth, png_ptr->iwidth) + 1);
+   png_debug1(3, "rowbytes = %lu,", (unsigned long)png_ptr->rowbytes);
+   png_debug1(3, "irowbytes = %lu",
+       (unsigned long)PNG_ROWBYTES(png_ptr->pixel_depth, png_ptr->iwidth) + 1);

   png_ptr->flags |= PNG_FLAG_ROW_INIT;
 }
-
-#ifdef PNG_SEQUENTIAL_READ_SUPPORTED
-int PNGAPI
-png_get_num_passes(png_structp png_ptr)
-{
-   if (png_ptr != NULL)
-   {
-      if (png_ptr->interlaced)
-         return 7;
-
-      else
-         return 1;
-   }
-
-   /* Here on error */
-   return 0;
-}
-
-png_uint_32 PNGAPI
-png_get_num_rows(png_structp png_ptr)
-{
-   if (png_ptr != NULL)
-   {
-      if (png_ptr->flags & PNG_FLAG_ROW_INIT)
-         return png_ptr->num_rows;
-
-      else
-         png_error(png_ptr, "Call png_start_read_image or png_read_update_info "
-            "before png_get_num_rows");
-   }
-
-   /* Here on error */
-   return 0;
-}
-
-png_uint_32 PNGAPI
-png_get_num_cols(png_structp png_ptr)
-{
-   if (png_ptr != NULL)
-   {
-      if (png_ptr->flags & PNG_FLAG_ROW_INIT)
-         return png_ptr->iwidth;
-      else
-         png_error(png_ptr, "Call png_start_read_image or png_read_update_info "
-            "before png_get_num_cols");
-   }
-
-   /* Here on error */
-   return 0;
-}
-#endif /* SEQUENTIAL READ */
 #endif /* PNG_READ_SUPPORTED */
--- a/pngset.c
+++ b/pngset.c
@@ -1,8 +1,8 @@

 /* pngset.c - storage of image information into info struct
 *
- * Last changed in libpng 1.5.0 [(PENDING RELEASE)]
- * Copyright (c) 1998-2010 Glenn Randers-Pehrson
+ * Last changed in libpng 1.5.1 [February 3, 2011]
+ * Copyright (c) 1998-2011 Glenn Randers-Pehrson
 * (Version 0.96 Copyright (c) 1996, 1997 Andreas Dilger)
 * (Version 0.88 Copyright (c) 1995, 1996 Guy Eric Schalnat, Group 42, Inc.)
 *
@@ -87,7 +87,7 @@ png_set_cHRM(png_structp png_ptr, png_infop info_ptr,
 #ifdef PNG_gAMA_SUPPORTED
 void PNGFAPI
 png_set_gAMA_fixed(png_structp png_ptr, png_infop info_ptr, png_fixed_point
-    gamma)
+    file_gamma)
 {
   png_debug1(1, "in %s storage function", "gAMA");

@@ -98,15 +98,15 @@ png_set_gAMA_fixed(png_structp png_ptr, png_infop info_ptr, png_fixed_point
    * wrong, therefore storing them (and setting PNG_INFO_gAMA)
    * must be wrong too.
    */
-   if (gamma > (png_fixed_point)PNG_UINT_31_MAX)
+   if (file_gamma > (png_fixed_point)PNG_UINT_31_MAX)
      png_warning(png_ptr, "Gamma too large, ignored");

-   else if (gamma <= 0)
+   else if (file_gamma <= 0)
      png_warning(png_ptr, "Negative or zero gamma ignored");

   else
   {
-      info_ptr->gamma = gamma;
+      info_ptr->gamma = file_gamma;
      info_ptr->valid |= PNG_INFO_gAMA;
   }
 }
@@ -352,7 +352,7 @@ png_set_sCAL_s(png_structp png_ptr, png_infop info_ptr,

   ++lengthw;

-   png_debug1(3, "allocating unit for info (%u bytes)", lengthw);
+   png_debug1(3, "allocating unit for info (%u bytes)", (unsigned int)lengthw);

   info_ptr->scal_s_width = (png_charp)png_malloc_warn(png_ptr, lengthw);

@@ -366,7 +366,7 @@ png_set_sCAL_s(png_structp png_ptr, png_infop info_ptr,

   ++lengthh;

-   png_debug1(3, "allocating unit for info (%u bytes)", lengthh);
+   png_debug1(3, "allocating unit for info (%u bytes)", (unsigned int)lengthh);

   info_ptr->scal_s_height = (png_charp)png_malloc_warn(png_ptr, lengthh);

@@ -522,27 +522,27 @@ png_set_sBIT(png_structp png_ptr, png_infop info_ptr,

 #ifdef PNG_sRGB_SUPPORTED
 void PNGAPI
-png_set_sRGB(png_structp png_ptr, png_infop info_ptr, int intent)
+png_set_sRGB(png_structp png_ptr, png_infop info_ptr, int srgb_intent)
 {
   png_debug1(1, "in %s storage function", "sRGB");

   if (png_ptr == NULL || info_ptr == NULL)
      return;

-   info_ptr->srgb_intent = (png_byte)intent;
+   info_ptr->srgb_intent = (png_byte)srgb_intent;
   info_ptr->valid |= PNG_INFO_sRGB;
 }

 void PNGAPI
 png_set_sRGB_gAMA_and_cHRM(png_structp png_ptr, png_infop info_ptr,
-    int intent)
+    int srgb_intent)
 {
   png_debug1(1, "in %s storage function", "sRGB_gAMA_and_cHRM");

   if (png_ptr == NULL || info_ptr == NULL)
      return;

-   png_set_sRGB(png_ptr, info_ptr, intent);
+   png_set_sRGB(png_ptr, info_ptr, srgb_intent);

 #  ifdef PNG_gAMA_SUPPORTED
   png_set_gAMA_fixed(png_ptr, info_ptr, 45455L);
@@ -751,10 +751,10 @@ png_set_text_2(png_structp png_ptr, png_infop info_ptr,
      if (textp->key == NULL)
         return(1);

-      png_debug2(2, "Allocated %lu bytes at %x in png_set_text",
+      png_debug2(2, "Allocated %lu bytes at %p in png_set_text",
          (unsigned long)(png_uint_32)
          (key_len + lang_len + lang_key_len + text_length + 4),
-          (int)textp->key);
+          textp->key);

      png_memcpy(textp->key, text_ptr[i].key,(png_size_t)(key_len));
      *(textp->key + key_len) = '\0';
--- a/pngstruct.h
+++ b/pngstruct.h
@@ -1,11 +1,11 @@

 /* pngstruct.h - header file for PNG reference library
 *
- * Copyright (c) 1998-2010 Glenn Randers-Pehrson
+ * Copyright (c) 1998-2011 Glenn Randers-Pehrson
 * (Version 0.96 Copyright (c) 1996, 1997 Andreas Dilger)
 * (Version 0.88 Copyright (c) 1995, 1996 Guy Eric Schalnat, Group 42, Inc.)
 *
- * Last changed in libpng version 1.5.0 - (PENDING RELEASE)
+ * Last changed in libpng 1.5.0 [January 6, 2011]
 *
 * This code is released under the libpng license.
 * For conditions of distribution and use, see the disclaimer
--- a/pngtest.c
+++ b/pngtest.c
@@ -1,8 +1,8 @@

 /* pngtest.c - a simple test program to test libpng
 *
- * Last changed in libpng 1.5.0 [(PENDING RELEASE)]
- * Copyright (c) 1998-2010 Glenn Randers-Pehrson
+ * Last changed in libpng 1.5.0 [January 6, 2011]
+ * Copyright (c) 1998-2011 Glenn Randers-Pehrson
 * (Version 0.96 Copyright (c) 1996, 1997 Andreas Dilger)
 * (Version 0.88 Copyright (c) 1995, 1996 Guy Eric Schalnat, Group 42, Inc.)
 *
@@ -425,7 +425,7 @@ static void PNGCBAPI
 pngtest_flush(png_structp png_ptr)
 {
   /* Do nothing; fflush() is said to be just a waste of energy. */
-   png_ptr = png_ptr;  /* Stifle compiler warning */
+   PNG_UNUSED(png_ptr)   /* Stifle compiler warning */
 }
 #endif

@@ -1784,4 +1784,4 @@ main(int argc, char *argv[])
 }

 /* Generate a compiler error if there is an old png.h in the search path. */
-typedef png_libpng_version_1_5_0beta55 Your_png_h_is_not_version_1_5_0beta55;
+typedef png_libpng_version_1_5_2rc01 Your_png_h_is_not_version_1_5_2rc01;
--- a/pngtrans.c
+++ b/pngtrans.c
@@ -1,8 +1,8 @@

 /* pngtrans.c - transforms the data in a row (used by both readers and writers)
 *
- * Last changed in libpng 1.5.0 [(PENDING RELEASE)]
- * Copyright (c) 1998-2010 Glenn Randers-Pehrson
+ * Last changed in libpng 1.5.2 [(PENDING RELEASE)]
+ * Copyright (c) 1998-2011 Glenn Randers-Pehrson
 * (Version 0.96 Copyright (c) 1996, 1997 Andreas Dilger)
 * (Version 0.88 Copyright (c) 1995, 1996 Guy Eric Schalnat, Group 42, Inc.)
 *
@@ -424,170 +424,115 @@ png_do_packswap(png_row_infop row_info, png_bytep row)

 #if defined(PNG_WRITE_FILLER_SUPPORTED) || \
    defined(PNG_READ_STRIP_ALPHA_SUPPORTED)
-/* Remove filler or alpha byte(s) */
+/* Remove a channel - this used to be 'png_do_strip_filler' but it used a
+ * somewhat weird combination of flags to determine what to do.  All the calls
+ * to png_do_strip_filler are changed in 1.5.2 to call this instead with the
+ * correct arguments.
+ *
+ * The routine isn't general - the channel must be the channel at the start or
+ * end (not in the middle) of each pixel.
+ */
 void /* PRIVATE */
-png_do_strip_filler(png_row_infop row_info, png_bytep row, png_uint_32 flags)
+png_do_strip_channel(png_row_infop row_info, png_bytep row, int at_start)
 {
-   png_debug(1, "in png_do_strip_filler");
+   png_bytep sp = row; /* source pointer */
+   png_bytep dp = row; /* destination pointer */
+   png_bytep ep = row + row_info->rowbytes; /* One beyond end of row */

+   /* At the start sp will point to the first byte to copy and dp to where
+    * it is copied to.  ep always points just beyond the end of the row, so
+    * the loop simply copies (channels-1) channels until sp reaches ep.
+    */
+   /* GA, GX, XG cases */
+   if (row_info->channels == 2)
   {
-      png_bytep sp = row;
-      png_bytep dp = row;
-      png_uint_32 row_width = row_info->width;
-      png_uint_32 i;
-
-      if ((row_info->color_type == PNG_COLOR_TYPE_RGB ||
-          (row_info->color_type == PNG_COLOR_TYPE_RGB_ALPHA &&
-          (flags & PNG_FLAG_STRIP_ALPHA))) &&
-          row_info->channels == 4)
+      if (row_info->bit_depth == 8)
      {
-         if (row_info->bit_depth == 8)
-         {
-            /* This converts from RGBX or RGBA to RGB */
-            if (flags & PNG_FLAG_FILLER_AFTER)
-            {
-               dp += 3; sp += 4;
-               for (i = 1; i < row_width; i++)
-               {
-                  *dp++ = *sp++;
-                  *dp++ = *sp++;
-                  *dp++ = *sp++;
-                  sp++;
-               }
-            }
+         if (at_start) /* Skip initial filler */
+            ++sp;
+         else          /* Skip initial channels and, for sp, the filler */
+            sp += 2, ++dp;

-            /* This converts from XRGB or ARGB to RGB */
-            else
-            {
-               for (i = 0; i < row_width; i++)
-               {
-                  sp++;
-                  *dp++ = *sp++;
-                  *dp++ = *sp++;
-                  *dp++ = *sp++;
-               }
-            }
-            row_info->pixel_depth = 24;
-            row_info->rowbytes = row_width * 3;
-         }
+         /* For a 1 pixel wide image there is nothing to do */
+         while (sp < ep)
+            *dp++ = *sp, sp += 2;

-         else /* if (row_info->bit_depth == 16) */
-         {
-            if (flags & PNG_FLAG_FILLER_AFTER)
-            {
-               /* This converts from RRGGBBXX or RRGGBBAA to RRGGBB */
-               sp += 8; dp += 6;
-               for (i = 1; i < row_width; i++)
-               {
-                  /* This could be (although png_memcpy is probably slower):
-                  png_memcpy(dp, sp, 6);
-                  sp += 8;
-                  dp += 6;
-                  */
-
-                  *dp++ = *sp++;
-                  *dp++ = *sp++;
-                  *dp++ = *sp++;
-                  *dp++ = *sp++;
-                  *dp++ = *sp++;
-                  *dp++ = *sp++;
-                  sp += 2;
-               }
-            }
-
-            else
-            {
-               /* This converts from XXRRGGBB or AARRGGBB to RRGGBB */
-               for (i = 0; i < row_width; i++)
-               {
-                  /* This could be (although png_memcpy is probably slower):
-                  png_memcpy(dp, sp, 6);
-                  sp += 8;
-                  dp += 6;
-                  */
-
-                  sp += 2;
-                  *dp++ = *sp++;
-                  *dp++ = *sp++;
-                  *dp++ = *sp++;
-                  *dp++ = *sp++;
-                  *dp++ = *sp++;
-                  *dp++ = *sp++;
-               }
-            }
-
-            row_info->pixel_depth = 48;
-            row_info->rowbytes = row_width * 6;
-         }
-         row_info->channels = 3;
+         row_info->pixel_depth = 8;
      }

-      else if ((row_info->color_type == PNG_COLOR_TYPE_GRAY ||
-         (row_info->color_type == PNG_COLOR_TYPE_GRAY_ALPHA &&
-         (flags & PNG_FLAG_STRIP_ALPHA))) &&
-          row_info->channels == 2)
+      else if (row_info->bit_depth == 16)
      {
-         if (row_info->bit_depth == 8)
-         {
-            if (flags & PNG_FLAG_FILLER_AFTER)
-            {
-               /* This converts from GX or GA to G */
-               for (i = 0; i < row_width; i++)
-               {
-                  *dp++ = *sp++;
-                  sp++;
-               }
-            }
+         if (at_start)
+            sp += 2;
+         else
+            sp += 4, dp += 2;

-            else
-            {
-               /* This converts from XG or AG to G */
-               for (i = 0; i < row_width; i++)
-               {
-                  sp++;
-                  *dp++ = *sp++;
-               }
-            }
+         while (sp < ep)
+            *dp++ = *sp++, *dp++ = *sp, sp += 3;

-            row_info->pixel_depth = 8;
-            row_info->rowbytes = row_width;
-         }
-
-         else /* if (row_info->bit_depth == 16) */
-         {
-            if (flags & PNG_FLAG_FILLER_AFTER)
-            {
-               /* This converts from GGXX or GGAA to GG */
-               sp += 4; dp += 2;
-               for (i = 1; i < row_width; i++)
-               {
-                  *dp++ = *sp++;
-                  *dp++ = *sp++;
-                  sp += 2;
-               }
-            }
-
-            else
-            {
-               /* This converts from XXGG or AAGG to GG */
-               for (i = 0; i < row_width; i++)
-               {
-                  sp += 2;
-                  *dp++ = *sp++;
-                  *dp++ = *sp++;
-               }
-            }
-
-            row_info->pixel_depth = 16;
-            row_info->rowbytes = row_width * 2;
-         }
-         row_info->channels = 1;
+         row_info->pixel_depth = 16;
      }

-      if (flags & PNG_FLAG_STRIP_ALPHA)
-        row_info->color_type = (png_byte)(row_info->color_type &
-            ~PNG_COLOR_MASK_ALPHA);
+      else
+         return; /* bad bit depth */
+
+      row_info->channels = 1;
+
+      /* Finally fix the color type if it records an alpha channel */
+      if (row_info->color_type == PNG_COLOR_TYPE_GRAY_ALPHA)
+         row_info->color_type = PNG_COLOR_TYPE_GRAY;
   }
+
+   /* RGBA, RGBX, XRGB cases */
+   else if (row_info->channels == 4)
+   {
+      if (row_info->bit_depth == 8)
+      {
+         if (at_start) /* Skip initial filler */
+            ++sp;
+         else          /* Skip initial channels and, for sp, the filler */
+            sp += 4, dp += 3;
+
+         /* Note that the loop adds 3 to dp and 4 to sp each time. */
+         while (sp < ep)
+            *dp++ = *sp++, *dp++ = *sp++, *dp++ = *sp, sp += 2;
+
+         row_info->pixel_depth = 24;
+      }
+
+      else if (row_info->bit_depth == 16)
+      {
+         if (at_start)
+            sp += 2;
+         else
+            sp += 8, dp += 6;
+
+         while (sp < ep)
+         {
+            /* Copy 6 bytes, skip 2 */
+            *dp++ = *sp++, *dp++ = *sp++;
+            *dp++ = *sp++, *dp++ = *sp++;
+            *dp++ = *sp++, *dp++ = *sp, sp += 3;
+         }
+
+         row_info->pixel_depth = 48;
+      }
+
+      else
+         return; /* bad bit depth */
+
+      row_info->channels = 3;
+
+      /* Finally fix the color type if it records an alpha channel */
+      if (row_info->color_type == PNG_COLOR_TYPE_RGB_ALPHA)
+         row_info->color_type = PNG_COLOR_TYPE_RGB;
+   }
+
+   else
+      return; /* The filler channel has gone already */
+
+   /* Fix the rowbytes value. */
+   row_info->rowbytes = dp-row;
 }
 #endif

@@ -672,6 +617,7 @@ png_do_bgr(png_row_infop row_info, png_bytep row)

 #if defined(PNG_READ_USER_TRANSFORM_SUPPORTED) || \
    defined(PNG_WRITE_USER_TRANSFORM_SUPPORTED)
+#ifdef PNG_USER_TRANSFORM_PTR_SUPPORTED
 void PNGAPI
 png_set_user_transform_info(png_structp png_ptr, png_voidp
   user_transform_ptr, int user_transform_depth, int user_transform_channels)
@@ -680,34 +626,49 @@ png_set_user_transform_info(png_structp png_ptr, png_voidp

   if (png_ptr == NULL)
      return;
-#ifdef PNG_USER_TRANSFORM_PTR_SUPPORTED
   png_ptr->user_transform_ptr = user_transform_ptr;
   png_ptr->user_transform_depth = (png_byte)user_transform_depth;
   png_ptr->user_transform_channels = (png_byte)user_transform_channels;
-#else
-   if (user_transform_ptr || user_transform_depth || user_transform_channels)
-      png_warning(png_ptr,
-        "This version of libpng does not support user transform info");
-#endif
 }
+#endif

 /* This function returns a pointer to the user_transform_ptr associated with
 * the user transform functions.  The application should free any memory
 * associated with this pointer before png_write_destroy and png_read_destroy
 * are called.
 */
+#ifdef PNG_USER_TRANSFORM_PTR_SUPPORTED
 png_voidp PNGAPI
-png_get_user_transform_ptr(png_structp png_ptr)
+png_get_user_transform_ptr(png_const_structp png_ptr)
 {
   if (png_ptr == NULL)
      return (NULL);

-#ifdef PNG_USER_TRANSFORM_PTR_SUPPORTED
   return ((png_voidp)png_ptr->user_transform_ptr);
-#else
-   return (NULL);
-#endif
 }
+#endif
+
+#ifdef PNG_USER_TRANSFORM_INFO_SUPPORTED
+png_uint_32 PNGAPI
+png_get_current_row_number(png_const_structp png_ptr)
+{
+   /* See the comments in png.h - this is the sub-image row when reading and
+    * interlaced image.
+    */
+   if (png_ptr != NULL)
+      return png_ptr->row_number;
+
+   return PNG_UINT_32_MAX; /* help the app not to fail silently */
+}
+
+png_byte PNGAPI
+png_get_current_pass_number(png_const_structp png_ptr)
+{
+   if (png_ptr != NULL)
+      return png_ptr->pass;
+   return 8; /* invalid */
+}
+#endif /* PNG_USER_TRANSFORM_INFO_SUPPORTED */
 #endif /* PNG_READ_USER_TRANSFORM_SUPPORTED ||
          PNG_WRITE_USER_TRANSFORM_SUPPORTED */
 #endif /* PNG_READ_SUPPORTED || PNG_WRITE_SUPPORTED */
--- a/pngvalid.c
+++ b/pngvalid.c
--- a/pngwio.c
+++ b/pngwio.c
@@ -1,8 +1,8 @@

 /* pngwio.c - functions for data output
 *
- * Last changed in libpng 1.5.0 [(PENDING RELEASE)]
- * Copyright (c) 1998-2010 Glenn Randers-Pehrson
+ * Last changed in libpng 1.5.0 [January 6, 2011]
+ * Copyright (c) 1998-2011 Glenn Randers-Pehrson
 * (Version 0.96 Copyright (c) 1996, 1997 Andreas Dilger)
 * (Version 0.88 Copyright (c) 1995, 1996 Guy Eric Schalnat, Group 42, Inc.)
 *
--- a/pngwrite.c
+++ b/pngwrite.c
@@ -1,8 +1,8 @@

 /* pngwrite.c - general routines to write a PNG file
 *
- * Last changed in libpng 1.5.0 [(PENDING RELEASE)]
- * Copyright (c) 1998-2010 Glenn Randers-Pehrson
+ * Last changed in libpng 1.5.1 [February 3, 2011]
+ * Copyright (c) 1998-2011 Glenn Randers-Pehrson
 * (Version 0.96 Copyright (c) 1996, 1997 Andreas Dilger)
 * (Version 0.88 Copyright (c) 1995, 1996 Guy Eric Schalnat, Group 42, Inc.)
 *
@@ -783,7 +783,8 @@ png_write_row(png_structp png_ptr, png_const_bytep row)
   png_debug1(3, "row_info->channels = %d", png_ptr->row_info.channels);
   png_debug1(3, "row_info->bit_depth = %d", png_ptr->row_info.bit_depth);
   png_debug1(3, "row_info->pixel_depth = %d", png_ptr->row_info.pixel_depth);
-   png_debug1(3, "row_info->rowbytes = %u", png_ptr->row_info.rowbytes);
+   png_debug1(3, "row_info->rowbytes = %lu",
+       (unsigned long)png_ptr->row_info.rowbytes);

   /* Copy user's row into buffer, leaving room for filter byte. */
   png_memcpy(png_ptr->row_buf + 1, row, png_ptr->row_info.rowbytes);
@@ -1597,8 +1598,8 @@ png_write_png(png_structp png_ptr, png_infop info_ptr,
   /* It is REQUIRED to call this to finish writing the rest of the file */
   png_write_end(png_ptr, info_ptr);

-   transforms = transforms; /* Quiet compiler warnings */
-   params = params;
+   PNG_UNUSED(transforms)   /* Quiet compiler warnings */
+   PNG_UNUSED(params)
 }
 #endif
 #endif /* PNG_WRITE_SUPPORTED */
--- a/pngwtran.c
+++ b/pngwtran.c
@@ -1,8 +1,8 @@

 /* pngwtran.c - transforms the data in a row for PNG writers
 *
- * Last changed in libpng 1.5.0 [(PENDING RELEASE)]
- * Copyright (c) 1998-2010 Glenn Randers-Pehrson
+ * Last changed in libpng 1.5.2 [(PENDING RELEASE)]
+ * Copyright (c) 1998-2011 Glenn Randers-Pehrson
 * (Version 0.96 Copyright (c) 1996, 1997 Andreas Dilger)
 * (Version 0.88 Copyright (c) 1995, 1996 Guy Eric Schalnat, Group 42, Inc.)
 *
@@ -44,8 +44,8 @@ png_do_write_transformations(png_structp png_ptr)

 #ifdef PNG_WRITE_FILLER_SUPPORTED
   if (png_ptr->transformations & PNG_FILLER)
-      png_do_strip_filler(&(png_ptr->row_info), png_ptr->row_buf + 1,
-          png_ptr->flags);
+      png_do_strip_channel(&(png_ptr->row_info), png_ptr->row_buf + 1,
+         !(png_ptr->flags & PNG_FILLER_AFTER));
 #endif

 #ifdef PNG_WRITE_PACKSWAP_SUPPORTED
--- a/pngwutil.c
+++ b/pngwutil.c
@@ -1,8 +1,8 @@

 /* pngwutil.c - utilities to write a PNG file
 *
- * Last changed in libpng 1.5.0 [(PENDING RELEASE)]
- * Copyright (c) 1998-2010 Glenn Randers-Pehrson
+ * Last changed in libpng 1.5.0 [January 6, 2011]
+ * Copyright (c) 1998-2011 Glenn Randers-Pehrson
 * (Version 0.96 Copyright (c) 1996, 1997 Andreas Dilger)
 * (Version 0.88 Copyright (c) 1995, 1996 Guy Eric Schalnat, Group 42, Inc.)
 *
--- a/projects/visualc71/libpng.vcproj
+++ b/projects/visualc71/libpng.vcproj
@@ -30,9 +30,8 @@
 				Name="VCCustomBuildTool"/>
 			<Tool
 				Name="VCLinkerTool"
-				OutputFile="$(OutDir)/libpng14.dll"
-				LinkIncremental="1"
-				ModuleDefinitionFile="..\..\scripts\pngwin.def"/>
+				OutputFile="$(OutDir)/libpng15.dll"
+				LinkIncremental="1"/>
 			<Tool
 				Name="VCMIDLTool"/>
 			<Tool
@@ -79,8 +78,7 @@
 				Name="VCCustomBuildTool"/>
 			<Tool
 				Name="VCLinkerTool"
-				OutputFile="$(OutDir)/libpng14d.dll"
-				ModuleDefinitionFile="..\..\scripts\pngwin.def"
+				OutputFile="$(OutDir)/libpng15d.dll"
 				GenerateDebugInformation="TRUE"/>
 			<Tool
 				Name="VCMIDLTool"/>
@@ -128,7 +126,7 @@
 				Name="VCCustomBuildTool"/>
 			<Tool
 				Name="VCLinkerTool"
-				OutputFile="$(OutDir)/libpng14vb.dll"
+				OutputFile="$(OutDir)/libpng15vb.dll"
 				LinkIncremental="1"/>
 			<Tool
 				Name="VCMIDLTool"/>
@@ -340,27 +338,6 @@
 			<File
 				RelativePath="..\..\pngtrans.c">
 			</File>
-			<File
-				RelativePath="..\..\scripts\pngwin.def">
-				<FileConfiguration
-					Name="DLL VB|Win32"
-					ExcludedFromBuild="TRUE">
-					<Tool
-						Name="VCCustomBuildTool"/>
-				</FileConfiguration>
-				<FileConfiguration
-					Name="LIB Release|Win32"
-					ExcludedFromBuild="TRUE">
-					<Tool
-						Name="VCCustomBuildTool"/>
-				</FileConfiguration>
-				<FileConfiguration
-					Name="LIB Debug|Win32"
-					ExcludedFromBuild="TRUE">
-					<Tool
-						Name="VCCustomBuildTool"/>
-				</FileConfiguration>
-			</File>
 			<File
 				RelativePath="..\..\pngwio.c">
 			</File>
--- a/projects/visualc71/pngtest.vcproj
+++ b/projects/visualc71/pngtest.vcproj
@@ -130,7 +130,7 @@ $(TargetPath) ..\..\pngtest.png $(IntDir)\pngout.png"
 				Name="VCLinkerTool"
 				OutputFile="$(OutDir)/pngtest.exe"
 				LinkIncremental="1"
-				IgnoreDefaultLibraryNames="$(IntDir)\libpng14b.lib"
+				IgnoreDefaultLibraryNames="$(IntDir)\libpng15b.lib"
 				SubSystem="1"
 				TargetMachine="1"/>
 			<Tool
--- a/projects/vstudio/readme.txt
+++ b/projects/vstudio/readme.txt
@@ -1,7 +1,7 @@

 VisualStudio instructions

-libpng version 1.5.0beta55 - November 21, 2010
+libpng version 1.5.2rc01 - March 19, 2011

 Copyright (c) 1998-2010 Glenn Randers-Pehrson

--- a/projects/vstudio/zlib.props
+++ b/projects/vstudio/zlib.props
@@ -2,7 +2,7 @@
 <!--
 * zlib.props - location of zlib source
 *
- * libpng version 1.5.0beta55 - November 21, 2010
+ * libpng version 1.5.2rc01 - March 19, 2011
 *
 * Copyright (c) 1998-2010 Glenn Randers-Pehrson
 *
--- a/scripts/README.txt
+++ b/scripts/README.txt
@@ -1,9 +1,9 @@

-Makefiles for  libpng version 1.5.0beta55 - November 21, 2010
+Makefiles for  libpng version 1.5.2rc01 - March 19, 2011

 pnglibconf.h.prebuilt       =>  Stores configuration settings
 makefile.linux    =>  Linux/ELF makefile
-                       (gcc, creates libpng15.so.15.1.5.0beta55)
+                       (gcc, creates libpng15.so.15.1.5.2rc01)
 makefile.gcc      =>  Generic makefile (gcc, creates static libpng.a)
 makefile.knr      =>  Archaic UNIX Makefile that converts files with
                       ansi2knr (Requires ansi2knr.c from
@@ -20,7 +20,7 @@ pnglibconf.h.prebuilt       =>  Stores configuration settings
 makefile.dec      =>  DEC Alpha UNIX makefile
 makefile.dj2      =>  DJGPP 2 makefile
 makefile.elf      =>  Linux/ELF makefile symbol versioning,
-                       (gcc, creates libpng15.so.15.1.5.0beta55)
+                       (gcc, creates libpng15.so.15.1.5.2rc01)
 makefile.freebsd  =>  FreeBSD makefile
 makefile.gcc      =>  Generic gcc makefile
 makefile.hpgcc    =>  HPUX makefile using gcc
@@ -35,12 +35,12 @@ pnglibconf.h.prebuilt       =>  Stores configuration settings
 makefile.os2      =>  OS/2 Makefile (gcc and emx, requires libpng.def)
 makefile.sco      =>  For SCO OSr5  ELF and Unixware 7 with Native cc
 makefile.sggcc    =>  Silicon Graphics (gcc,
-                       creates libpng15.so.15.1.5.0beta55)
+                       creates libpng15.so.15.1.5.2rc01)
 makefile.sgi      =>  Silicon Graphics IRIX makefile (cc, creates static lib)
 makefile.solaris  =>  Solaris 2.X makefile (gcc,
-                       creates libpng15.so.15.1.5.0beta55)
+                       creates libpng15.so.15.1.5.2rc01)
 makefile.so9      =>  Solaris 9 makefile (gcc,
-                       creates libpng15.so.15.1.5.0beta55)
+                       creates libpng15.so.15.1.5.2rc01)
 makefile.std      =>  Generic UNIX makefile (cc, creates static libpng.a)
 makefile.sunos    =>  Sun makefile
 makefile.32sunu   =>  Sun Ultra 32-bit makefile
--- a/scripts/checksym.awk
+++ b/scripts/checksym.awk
@@ -20,6 +20,7 @@ BEGIN{
   lasto = 0        # last ordinal value from png.h
   mastero = 0      # highest ordinal in master file
   symbolo = 0      # highest ordinal in png.h
+   missing = "error"# log an error on missing symbols
 }

 # Read existing definitions from the master file (the first
@@ -44,6 +45,13 @@ FILENAME==master && NF==2 && $2~/^@/ && $1!~/^;/ {
      print master ": bad export line format:", $0
   err = 1
 }
+FILENAME==master && $1==";missing" && NF==2{
+   # This allows the master file to control how missing symbols
+   # are handled; symbols that aren't in either the master or
+   # the new file.  Valid values are 'ignore', 'warning' and
+   # 'error'
+   missing = $2
+}
 FILENAME==master {
   next
 }
@@ -112,11 +120,19 @@ END{
         }
      }
      if (unexported != 0) {
-         # Symbols in the .def but not in the new file are errors
-         if (o-1 > unexported)
-            print "png.h: warning: unexported symbol definitions:", unexported "-" o-1
-         else
-            print "png.h: warning: unexported symbol definition:", unexported
+         # Symbols in the .def but not in the new file are errors, but
+         # the 'unexported' symbols aren't in either.  By default this
+         # is an error too (see the setting of 'missing' at the start),
+         # but this can be reset on the command line or by stuff in the
+         # file - see the comments above.
+         if (missing != "ignore") {
+            if (o-1 > unexported)
+               print "png.h:", missing ": missing symbols:", unexported "-" o-1
+            else
+               print "png.h:", missing ": missing symbol:", unexported
+            if (missing != "warning")
+               err = 1
+         }
         unexported = 0
      }
      if (symbol[o] != "" && removed[o] != "") {
--- a/scripts/def.dfn
+++ b/scripts/def.dfn
@@ -0,0 +1,38 @@
+/* def.dfn - define format of libpng.def
+ *
+ * Last changed in libpng version 1.5.0 [(PENDING RELEASE)]
+ * Copyright (c) 2010-2011 Glenn Randers-Pehrson
+ *
+ * This code is released under the libpng license.
+ * For conditions of distribution and use, see the disclaimer
+ * and license in png.h
+ */
+
+/* These macros exist to make the header and trailer shorter below: */
+#define S PNG_DEFN_MAGIC
+#define E PNG_DEFN_END
+
+/* Write the export file header: */
+S-;---------------------------------------------------------------E
+S-; LIBPNG module definition file for OS/2-E
+S-;---------------------------------------------------------------E
+S--E
+S-; If you give the library an explicit name one or other files-E
+S-; may need modifying to support the new name on one or more-E
+S-; systems.-E
+S-LIBRARY-E
+S-OS2 DESCRIPTION "PNG image compression library"-E
+S-OS2 CODE PRELOAD MOVEABLE DISCARDABLE-E
+S--E
+S-EXPORTS-E
+S-;Version 1.5.0beta58-E
+
+/* NOTE: @@@ is interpreted by the calling script as a signal to
+ * join the two things on either side, so we can do symbol
+ * substitution within the name, regular C ## joins the pp-tokens,
+ * not their final values.
+ */
+#define PNG_EXPORTA(ordinal, type, name, args, attributes)\
+	PNG_DEFN_MAGIC- SYMBOL_PREFIX @@@ name-PNG_DEFN_END
+
+#include "../png.h"
--- a/scripts/libpng-config-head.in
+++ b/scripts/libpng-config-head.in
@@ -11,7 +11,7 @@

 # Modeled after libxml-config.

-version=1.5.0beta55
+version=1.5.2rc01
 prefix=""
 libdir=""
 libs=""
--- a/scripts/libpng.pc.in
+++ b/scripts/libpng.pc.in
@@ -5,6 +5,6 @@ includedir=@includedir@/libpng15

 Name: libpng
 Description: Loads and saves PNG files
-Version: 1.5.0beta55
+Version: 1.5.2rc01
 Libs: -L${libdir} -lpng15
 Cflags: -I${includedir}
--- a/scripts/makefile.32sunu
+++ b/scripts/makefile.32sunu
@@ -1,6 +1,6 @@
 # makefile for libpng on Solaris 2.x with cc
 # Contributed by William L. Sebok, based on makefile.linux
-# Copyright (C) 2002, 2006, 2010 Glenn Randers-Pehrson
+# Copyright (C) 2002, 2006, 2010-2011 Glenn Randers-Pehrson
 # Copyright (C) 1998 Greg Roelofs
 # Copyright (C) 1996, 1997 Andreas Dilger

--- a/scripts/makefile.64sunu
+++ b/scripts/makefile.64sunu
@@ -1,6 +1,6 @@
 # makefile for libpng on Solaris 2.x with cc
 # Contributed by William L. Sebok, based on makefile.linux
-# Copyright (C) 2002, 2006, 2010 Glenn Randers-Pehrson
+# Copyright (C) 2002, 2006, 2010-2011 Glenn Randers-Pehrson
 # Copyright (C) 1998 Greg Roelofs
 # Copyright (C) 1996, 1997 Andreas Dilger

--- a/scripts/makefile.beos
+++ b/scripts/makefile.beos
@@ -1,6 +1,6 @@
 # makefile for libpng on BeOS x86 ELF with gcc
 # modified from makefile.linux by Sander Stoks
-# Copyright (C) 2002, 2006, 2008, 2010 Glenn Randers-Pehrson
+# Copyright (C) 2002, 2006, 2008, 2010-2011 Glenn Randers-Pehrson
 # Copyright (C) 1999 Greg Roelofs
 # Copyright (C) 1996, 1997 Andreas Dilger
 #
--- a/scripts/makefile.cegcc
+++ b/scripts/makefile.cegcc
@@ -23,7 +23,7 @@

 VERMAJ = 1
 VERMIN = 5
-VERMIC = 0
+VERMIC = 2
 VER = $(VERMAJ).$(VERMIN).$(VERMIC)
 NAME = libpng
 PACKAGE = $(NAME)-$(VER)
--- a/scripts/makefile.darwin
+++ b/scripts/makefile.darwin
@@ -1,5 +1,5 @@
 # makefile for libpng on Darwin / Mac OS X
-# Copyright (C) 2002, 2004, 2006, 2008, 2010 Glenn Randers-Pehrson
+# Copyright (C) 2002, 2004, 2006, 2008, 2010-2011 Glenn Randers-Pehrson
 # Copyright (C) 2001 Christoph Pfisterer
 # derived from makefile.linux:
 #  Copyright (C) 1998, 1999 Greg Roelofs
--- a/scripts/makefile.dec
+++ b/scripts/makefile.dec
@@ -1,5 +1,5 @@
 # makefile for libpng on DEC Alpha Unix
-# Copyright (C) 2000-2002, 2006, 2010 Glenn Randers-Pehrson
+# Copyright (C) 2000-2002, 2006, 2010-2011 Glenn Randers-Pehrson
 # Copyright (C) 1995 Guy Eric Schalnat, Group 42, Inc.
 #
 # This code is released under the libpng license.
--- a/scripts/makefile.dj2
+++ b/scripts/makefile.dj2
@@ -1,5 +1,5 @@
 # DJGPP (DOS gcc) makefile for libpng
-# Copyright (C) 2002, 2006, 2009-2010 Glenn Randers-Pehrson
+# Copyright (C) 2002, 2006, 2009-2010-2011 Glenn Randers-Pehrson
 # Copyright (C) 1995 Guy Eric Schalnat, Group 42, Inc.
 #
 # This code is released under the libpng license.
--- a/scripts/makefile.elf
+++ b/scripts/makefile.elf
@@ -1,5 +1,5 @@
 # makefile for libpng.a and libpng15.so on Linux ELF with gcc
-# Copyright (C) 1998, 1999, 2002, 2006, 2008, 2010 Greg Roelofs
+# Copyright (C) 1998, 1999, 2002, 2006, 2008, 2010-2011 Greg Roelofs
 # and Glenn Randers-Pehrson
 # Copyright (C) 1996, 1997 Andreas Dilger
 #
--- a/scripts/makefile.hp64
+++ b/scripts/makefile.hp64
@@ -1,5 +1,5 @@
 # makefile for libpng, HPUX (10.20 and 11.00) using the ANSI/C product.
-# Copyright (C) 1999-2002, 2006, 2009, 2010 Glenn Randers-Pehrson
+# Copyright (C) 1999-2002, 2006, 2009, 2010-2011 Glenn Randers-Pehrson
 # Copyright (C) 1995 Guy Eric Schalnat, Group 42
 # contributed by Jim Rice and updated by Chris Schleicher, Hewlett Packard
 #
--- a/scripts/makefile.hpgcc
+++ b/scripts/makefile.hpgcc
@@ -1,5 +1,5 @@
 # makefile for libpng on HP-UX using GCC with the HP ANSI/C linker.
-# Copyright (C) 2002, 2006-2008, 2010 Glenn Randers-Pehrson
+# Copyright (C) 2002, 2006-2008, 2010-2011 Glenn Randers-Pehrson
 # Copyright (C) 2001, Laurent faillie
 # Copyright (C) 1998, 1999 Greg Roelofs
 # Copyright (C) 1996, 1997 Andreas Dilger
--- a/scripts/makefile.hpux
+++ b/scripts/makefile.hpux
@@ -1,5 +1,5 @@
 # makefile for libpng, HPUX (10.20 and 11.00) using the ANSI/C product.
-# Copyright (C) 1999-2002, 2006, 2010 Glenn Randers-Pehrson
+# Copyright (C) 1999-2002, 2006, 2010-2011 Glenn Randers-Pehrson
 # Copyright (C) 1995 Guy Eric Schalnat, Group 42
 # contributed by Jim Rice and updated by Chris Schleicher, Hewlett Packard
 #
--- a/scripts/makefile.linux
+++ b/scripts/makefile.linux
@@ -1,5 +1,5 @@
 # makefile for libpng.a and libpng15.so on Linux ELF with gcc
-# Copyright (C) 1998, 1999, 2002, 2006, 2008, 2010 Greg Roelofs and
+# Copyright (C) 1998, 1999, 2002, 2006, 2008, 2010-2011 Greg Roelofs and
 # Glenn Randers-Pehrson
 # Copyright (C) 1996, 1997 Andreas Dilger
 #
@@ -10,7 +10,7 @@
 # Library name:
 LIBNAME = libpng15
 PNGMAJ = 15
-RELEASE = 0
+RELEASE = 2

 # Shared library names:
 LIBSO=$(LIBNAME).so
--- a/scripts/makefile.ne12bsd
+++ b/scripts/makefile.ne12bsd
@@ -17,7 +17,7 @@ INCSDIR=${LOCALBASE}/include/libpng15

 LIB=	png15
 SHLIB_MAJOR=	0
-SHLIB_MINOR=	1.5.0beta55
+SHLIB_MINOR=	1.5.2rc01
 SRCS=	png.c pngset.c pngget.c pngrutil.c pngtrans.c pngwutil.c \
 	pngread.c pngrio.c pngwio.c pngwrite.c pngrtran.c \
 	pngwtran.c pngmem.c pngerror.c pngpread.c
--- a/scripts/makefile.netbsd
+++ b/scripts/makefile.netbsd
@@ -16,8 +16,8 @@ MANDIR= ${LOCALBASE}/man
 INCSDIR=${LOCALBASE}/include

 LIB=	png
-SHLIB_MAJOR=	3
-SHLIB_MINOR=	1.5.0beta55
+SHLIB_MAJOR=	15
+SHLIB_MINOR=	1.5.2rc01
 SRCS=	png.c pngset.c pngget.c pngrutil.c pngtrans.c pngwutil.c \
 	pngread.c pngrio.c pngwio.c pngwrite.c pngrtran.c \
 	pngwtran.c pngmem.c pngerror.c pngpread.c
--- a/scripts/makefile.openbsd
+++ b/scripts/makefile.openbsd
@@ -10,8 +10,8 @@ PREFIX?= /usr/local
 LIBDIR=	${PREFIX}/lib
 MANDIR= ${PREFIX}/man/cat

-SHLIB_MAJOR=	0
-SHLIB_MINOR=	1.5.0beta55
+SHLIB_MAJOR=	15
+SHLIB_MINOR=	1.5.2rc01

 LIB=	png
 SRCS=	png.c pngerror.c pngget.c pngmem.c pngpread.c \
--- a/scripts/makefile.os2
+++ b/scripts/makefile.os2
@@ -1,77 +0,0 @@
-# makefile for libpng on OS/2 with gcc
-#
-# This code is released under the libpng license.
-# For conditions of distribution and use, see the disclaimer
-# and license in png.h
-
-# Related files: scripts/pngwin.def
-
-CC=gcc -Zomf -s
-
-# Where the zlib library and include files are located
-ZLIBLIB=../zlib
-ZLIBINC=../zlib
-
-WARNMORE=-Wwrite-strings -Wpointer-arith -Wshadow \
-	-Wmissing-declarations -Wtraditional -Wcast-align \
-	-Wstrict-prototypes -Wmissing-prototypes #-Wconversion
-CFLAGS=-I$(ZLIBINC) -W -Wall -O6 -funroll-loops -malign-loops=2 \
-	-malign-functions=2 #$(WARNMORE) -g -DPNG_DEBUG=5
-LDFLAGS=-L. -L$(ZLIBLIB) -lpng -lzdll -Zcrtdll
-AR=emxomfar
-
-PNGLIB=png.lib
-IMPLIB=emximp
-SHAREDLIB=png.dll
-SHAREDLIBIMP=pngdll.lib
-
-OBJS = png.o pngset.o pngget.o pngrutil.o pngtrans.o pngwutil.o \
-	pngread.o pngrio.o pngwio.o pngwrite.o pngrtran.o \
-	pngwtran.o pngmem.o pngerror.o pngpread.o
-
-.SUFFIXES:      .c .o
-
-all: $(PNGLIB) $(SHAREDLIB) $(SHAREDLIBIMP)
-
-# see scripts/pnglibconf.mak for more options
-pnglibconf.h: scripts/pnglibconf.h.prebuilt
-	cp scripts/pnglibconf.h.prebuilt $@
-
-$(PNGLIB): $(OBJS)
-	$(AR) rc $@ $(OBJS)
-
-$(SHAREDLIB): $(OBJS) scripts/pngwin.def
-	$(CC) $(LDFLAGS) -Zdll -o $@ $^
-
-$(SHAREDLIBIMP): scripts/pngwin.def
-	$(IMPLIB) -o $@ $^
-
-pngtest.exe: pngtest.o png.dll pngdll.lib
-	$(CC) -o $@ $(CFLAGS) $< $(LDFLAGS)
-
-test: pngtest.exe
-	./pngtest.exe
-
-clean:
-	rm -f *.o $(PNGLIB) png.dll pngdll.lib pngtest.exe pngout.png \
-	pnglibconf.h
-
-# DO NOT DELETE THIS LINE -- make depend depends on it.
-
-png.o png.pic.o: png.h pngconf.h pnglibconf.h pngpriv.h pngstruct.h pnginfo.h pngdebug.h
-pngerror.o pngerror.pic.o: png.h pngconf.h pnglibconf.h pngpriv.h pngstruct.h pnginfo.h pngdebug.h
-pngrio.o pngrio.pic.o: png.h pngconf.h pnglibconf.h pngpriv.h pngstruct.h pnginfo.h pngdebug.h
-pngwio.o pngwio.pic.o: png.h pngconf.h pnglibconf.h pngpriv.h pngstruct.h pnginfo.h pngdebug.h
-pngmem.o pngmem.pic.o: png.h pngconf.h pnglibconf.h pngpriv.h pngstruct.h pnginfo.h pngdebug.h
-pngset.o pngset.pic.o: png.h pngconf.h pnglibconf.h pngpriv.h pngstruct.h pnginfo.h pngdebug.h
-pngget.o pngget.pic.o: png.h pngconf.h pnglibconf.h pngpriv.h pngstruct.h pnginfo.h pngdebug.h
-pngread.o pngread.pic.o: png.h pngconf.h pnglibconf.h pngpriv.h pngstruct.h pnginfo.h pngdebug.h
-pngrtran.o pngrtran.pic.o: png.h pngconf.h pnglibconf.h pngpriv.h pngstruct.h pnginfo.h pngdebug.h
-pngrutil.o pngrutil.pic.o: png.h pngconf.h pnglibconf.h pngpriv.h pngstruct.h pnginfo.h pngdebug.h
-pngtrans.o pngtrans.pic.o: png.h pngconf.h pnglibconf.h pngpriv.h pngstruct.h pnginfo.h pngdebug.h
-pngwrite.o pngwrite.pic.o: png.h pngconf.h pnglibconf.h pngpriv.h pngstruct.h pnginfo.h pngdebug.h
-pngwtran.o pngwtran.pic.o: png.h pngconf.h pnglibconf.h pngpriv.h pngstruct.h pnginfo.h pngdebug.h
-pngwutil.o pngwutil.pic.o: png.h pngconf.h pnglibconf.h pngpriv.h pngstruct.h pnginfo.h pngdebug.h
-pngpread.o pngpread.pic.o: png.h pngconf.h pnglibconf.h pngpriv.h pngstruct.h pnginfo.h pngdebug.h
-
-pngtest.o: png.h pngconf.h pnglibconf.h
--- a/scripts/makefile.sco
+++ b/scripts/makefile.sco
@@ -1,7 +1,7 @@
 # makefile for SCO OSr5  ELF and Unixware 7 with Native cc
 # Contributed by Mike Hopkirk (hops@sco.com) modified from Makefile.lnx
 #   force ELF build dynamic linking, SONAME setting in lib and RPATH in app
-# Copyright (C) 2002, 2006, 2010 Glenn Randers-Pehrson
+# Copyright (C) 2002, 2006, 2010-2011 Glenn Randers-Pehrson
 # Copyright (C) 1998 Greg Roelofs
 # Copyright (C) 1996, 1997 Andreas Dilger
 #
--- a/scripts/makefile.sggcc
+++ b/scripts/makefile.sggcc
@@ -1,5 +1,5 @@
 # makefile for libpng.a and libpng15.so, SGI IRIX with 'cc'
-# Copyright (C) 2001-2002, 2006, 2010 Glenn Randers-Pehrson
+# Copyright (C) 2001-2002, 2006, 2010-2011 Glenn Randers-Pehrson
 # Copyright (C) 1995 Guy Eric Schalnat, Group 42, Inc.
 #
 # This code is released under the libpng license.
--- a/scripts/makefile.sgi
+++ b/scripts/makefile.sgi
@@ -1,5 +1,5 @@
 # makefile for libpng.a and libpng15.so, SGI IRIX with 'cc'
-# Copyright (C) 2001-2002, 2006, 2007, 2010 Glenn Randers-Pehrson
+# Copyright (C) 2001-2002, 2006, 2007, 2010-2011 Glenn Randers-Pehrson
 # Copyright (C) 1995 Guy Eric Schalnat, Group 42, Inc.
 #
 # This code is released under the libpng license.
--- a/scripts/makefile.so9
+++ b/scripts/makefile.so9
@@ -1,7 +1,7 @@
 # makefile for libpng on Solaris 9 (beta) with Forte cc
 # Updated by Chad Schrock for Solaris 9
 # Contributed by William L. Sebok, based on makefile.linux
-# Copyright (C) 2002, 2006, 2008, 2010 Glenn Randers-Pehrson
+# Copyright (C) 2002, 2006, 2008, 2010-2011 Glenn Randers-Pehrson
 # Copyright (C) 1998-2001 Greg Roelofs
 # Copyright (C) 1996-1997 Andreas Dilger
 #
--- a/scripts/makefile.solaris
+++ b/scripts/makefile.solaris
@@ -1,5 +1,5 @@
 # makefile for libpng on Solaris 2.x with gcc
-# Copyright (C) 2004, 2006-2008, 2010 Glenn Randers-Pehrson
+# Copyright (C) 2004, 2006-2008, 2010-2011 Glenn Randers-Pehrson
 # Contributed by William L. Sebok, based on makefile.linux
 # Copyright (C) 1998 Greg Roelofs
 # Copyright (C) 1996, 1997 Andreas Dilger
--- a/scripts/makefile.solaris-x86
+++ b/scripts/makefile.solaris-x86
@@ -1,5 +1,5 @@
 # makefile for libpng on Solaris 2.x with gcc
-# Copyright (C) 2004, 2006-2008, 2010 Glenn Randers-Pehrson
+# Copyright (C) 2004, 2006-2008, 2010-2011 Glenn Randers-Pehrson
 # Contributed by William L. Sebok, based on makefile.linux
 # Copyright (C) 1998 Greg Roelofs
 # Copyright (C) 1996, 1997 Andreas Dilger
--- a/scripts/makefile.vcwin32
+++ b/scripts/makefile.vcwin32
@@ -1,6 +1,6 @@
 # makefile for libpng
 # Copyright (C) 1998 Tim Wegner
-# Copyright (C) 2006,2009 Glenn Randers-Pehrson
+# Copyright (C) 2006,2009,2011 Glenn Randers-Pehrson
 #
 # This code is released under the libpng license.
 # For conditions of distribution and use, see the disclaimer
@@ -15,7 +15,7 @@
 CC = cl
 LD = link
 AR = lib
-CFLAGS  = -nologo -MD -O2 -W3 -I..\zlib
+CFLAGS  = -nologo -D_CRT_SECURE_NO_DEPRECATE -MD -O2 -W3 -I..\zlib
 LDFLAGS = -nologo
 ARFLAGS = -nologo
 RM = del
@@ -36,8 +36,8 @@ OBJS  = $(OBJS1) $(OBJS2) $(OBJS3)
 all: libpng.lib

 # see scripts/pnglibconf.mak for more options
-pnglibconf.h: scripts/pnglibconf.h.prebuilt
-	cp scripts/pnglibconf.h.prebuilt $@
+pnglibconf.h: scripts\pnglibconf.h.prebuilt
+       copy scripts\pnglibconf.h.prebuilt $@

 png$(O): png.h pngconf.h pnglibconf.h pngpriv.h pngstruct.h pnginfo.h pngdebug.h
 	$(CC) -c $(CFLAGS) $*.c $(ERRFILE)
--- a/scripts/options.awk
+++ b/scripts/options.awk
@@ -1,9 +1,9 @@
 #!/bin/awk -f
 # scripts/options.awk - library build configuration control
 #
-# last changed in libpng version 1.5.0 - (PENDING RELEASE)
+# last changed in libpng version 1.5.0 - January 6, 2011
 #
-# Copyright (c) 1998-2010 Glenn Randers-Pehrson
+# Copyright (c) 1998-2011 Glenn Randers-Pehrson
 #
 # This code is released under the libpng license.
 # For conditions of distribution and use, see the disclaimer
--- a/scripts/pnglibconf.dfa
+++ b/scripts/pnglibconf.dfa
@@ -6,9 +6,9 @@
 #
 com pnglibconf.h - library build configuration
 com
-com libpng version 1.5.0 - (PENDING RELEASE)
+com libpng version 1.5.0 - January 6, 2011
 com
-com Copyright (c) 1998-2010 Glenn Randers-Pehrson
+com Copyright (c) 1998-2011 Glenn Randers-Pehrson
 com
 com This code is released under the libpng license.
 com For conditions of distribution and use, see the disclaimer
@@ -301,9 +301,10 @@ option READ_16BIT requires READ enables 16BIT
 option READ_QUANTIZE requires READ

 option READ_TRANSFORMS requires READ
-= NO_READ_TRANSFORMS PNG_READ_TRANSFORMS_NOT_SUPPORTED
+= NO_READ_TRANSFORMS READ_TRANSFORMS_NOT_SUPPORTED

 option READ_EXPAND requires READ_TRANSFORMS
+option READ_EXPAND_16 requires READ_TRANSFORMS READ_16BIT enables READ_EXPAND
 option READ_SHIFT requires READ_TRANSFORMS
 option READ_PACK requires READ_TRANSFORMS
 option READ_BGR requires READ_TRANSFORMS
@@ -332,12 +333,12 @@ option SEQUENTIAL_READ requires READ
 #option READ_INTERLACING requires READ

 option READ_COMPOSITE_NODIV requires READ
-= NO_READ_COMPOSITE_NODIV PNG_NO_READ_COMPOSITED_NODIV
+= NO_READ_COMPOSITE_NODIV NO_READ_COMPOSITED_NODIV

 # Inch conversions

 option INCH_CONVERSIONS
-= INCH_CONVERSIONS PNG_INCH_CONVERSIONS
+= INCH_CONVERSIONS INCH_CONVERSIONS

 # IN DEVELOPMENT
 # These are currently experimental features, define them if you want
@@ -355,7 +356,7 @@ option WRITE
 option WRITE_16BIT requires WRITE enables 16BIT

 option WRITE_TRANSFORMS requires WRITE
-= NO_WRITE_TRANSFORMS PNG_WRITE_TRANSFORMS_NOT_SUPPORTED
+= NO_WRITE_TRANSFORMS WRITE_TRANSFORMS_NOT_SUPPORTED

 option WRITE_SHIFT requires WRITE_TRANSFORMS
 option WRITE_PACK requires WRITE_TRANSFORMS
@@ -380,8 +381,10 @@ option WRITE_WEIGHTED_FILTER requires WRITE

 option WRITE_FLUSH requires WRITE

-# Note: this can be turned off explicitly, is this correct?
+# Note: these can be turned off explicitly if not required by the
+# apps implementing the user transforms
 option USER_TRANSFORM_PTR if READ_USER_TRANSFORM WRITE_USER_TRANSFORM
+option USER_TRANSFORM_INFO if READ_USER_TRANSFORM WRITE_USER_TRANSFORM

 # Any chunks you are not interested in, you can undef here.  The
 # ones that allocate memory may be expecially important (hIST,
--- a/scripts/pnglibconf.h.prebuilt
+++ b/scripts/pnglibconf.h.prebuilt
@@ -3,173 +3,179 @@

 /* pnglibconf.h - library build configuration */

-/* libpng version 1.5.0 - last changed on (PENDING RELEASE) */
+/* libpng version 1.5.0 - last changed on February 11, 2011 */

-/* Copyright (c) 1998-2010 Glenn Randers-Pehrson */
+/* Copyright (c) 1998-2011 Glenn Randers-Pehrson */

 /* This code is released under the libpng license. */
 /* For conditions of distribution and use, see the disclaimer */
 /* and license in png.h */

 /* pnglibconf.h */
-/* Machine generated file: DO NOT EDIT */
 /* Derived from: scripts/pnglibconf.dfa */
+/* If you edit this file by hand you must obey the rules expressed in */
+/* pnglibconf.dfa with respect to the dependencies between the following */
+/* symbols.  It is much better to generate a new file using */
+/* scripts/libpngconf.mak */
+  
 #ifndef PNGLCONF_H
 #define PNGLCONF_H
 /* settings */
-#define PNG_MAX_GAMMA_8 11
-#define PNG_CALLOC_SUPPORTED
-#define PNG_QUANTIZE_RED_BITS 5
-#define PNG_USER_WIDTH_MAX 1000000L
-#define PNG_QUANTIZE_GREEN_BITS 5
 #define PNG_API_RULE 0
-#define PNG_QUANTIZE_BLUE_BITS 5
-#define PNG_USER_CHUNK_CACHE_MAX 0
-#define PNG_USER_HEIGHT_MAX 1000000L
-#define PNG_sCAL_PRECISION 5
+#define PNG_CALLOC_SUPPORTED
 #define PNG_COST_SHIFT 3
-#define PNG_WEIGHT_SHIFT 8
-#define PNG_USER_CHUNK_MALLOC_MAX 0
 #define PNG_DEFAULT_READ_MACROS 1
-#define PNG_ZBUF_SIZE 8192
 #define PNG_GAMMA_THRESHOLD_FIXED 5000
+#define PNG_MAX_GAMMA_8 11
+#define PNG_QUANTIZE_BLUE_BITS 5
+#define PNG_QUANTIZE_GREEN_BITS 5
+#define PNG_QUANTIZE_RED_BITS 5
+#define PNG_sCAL_PRECISION 5
+#define PNG_USER_CHUNK_CACHE_MAX 0
+#define PNG_USER_CHUNK_MALLOC_MAX 0
+#define PNG_USER_HEIGHT_MAX 1000000L
+#define PNG_USER_WIDTH_MAX 1000000L
+#define PNG_WEIGHT_SHIFT 8
+#define PNG_ZBUF_SIZE 8192
 /* end of settings */
 /* options */
-#define PNG_INFO_IMAGE_SUPPORTED
-#define PNG_HANDLE_AS_UNKNOWN_SUPPORTED
-#define PNG_POINTER_INDEXING_SUPPORTED
-#define PNG_WARNINGS_SUPPORTED
-#define PNG_FLOATING_ARITHMETIC_SUPPORTED
-#define PNG_WRITE_SUPPORTED
-#define PNG_WRITE_INTERLACING_SUPPORTED
-#define PNG_WRITE_16BIT_SUPPORTED
-#define PNG_EASY_ACCESS_SUPPORTED
-#define PNG_ALIGN_MEMORY_SUPPORTED
-#define PNG_WRITE_WEIGHTED_FILTER_SUPPORTED
-#define PNG_WRITE_UNKNOWN_CHUNKS_SUPPORTED
-#define PNG_USER_LIMITS_SUPPORTED
-#define PNG_FIXED_POINT_SUPPORTED
-/*#undef PNG_ERROR_NUMBERS_SUPPORTED*/
-#define PNG_ERROR_TEXT_SUPPORTED
-#define PNG_READ_SUPPORTED
-/*#undef PNG_READ_16_TO_8_ACCURATE_SCALE_SUPPORTED*/
-#define PNG_BENIGN_ERRORS_SUPPORTED
-#define PNG_SETJMP_SUPPORTED
-#define PNG_WRITE_FLUSH_SUPPORTED
-#define PNG_MNG_FEATURES_SUPPORTED
-#define PNG_FLOATING_POINT_SUPPORTED
-#define PNG_INCH_CONVERSIONS_SUPPORTED
-#define PNG_STDIO_SUPPORTED
-#define PNG_READ_UNKNOWN_CHUNKS_SUPPORTED
-#define PNG_USER_MEM_SUPPORTED
-#define PNG_IO_STATE_SUPPORTED
-#define PNG_SET_USER_LIMITS_SUPPORTED
-#define PNG_READ_ANCILLARY_CHUNKS_SUPPORTED
-#define PNG_WRITE_INT_FUNCTIONS_SUPPORTED
-#define PNG_WRITE_ANCILLARY_CHUNKS_SUPPORTED
-#define PNG_WRITE_FILTER_SUPPORTED
-#define PNG_SET_CHUNK_CACHE_LIMIT_SUPPORTED
-#define PNG_WRITE_iCCP_SUPPORTED
-#define PNG_READ_TRANSFORMS_SUPPORTED
-#define PNG_READ_GAMMA_SUPPORTED
-#define PNG_READ_bKGD_SUPPORTED
-#define PNG_UNKNOWN_CHUNKS_SUPPORTED
-#define PNG_READ_sCAL_SUPPORTED
-#define PNG_WRITE_hIST_SUPPORTED
-#define PNG_READ_OPT_PLTE_SUPPORTED
-#define PNG_SET_CHUNK_MALLOC_LIMIT_SUPPORTED
-#define PNG_WRITE_gAMA_SUPPORTED
-#define PNG_READ_GRAY_TO_RGB_SUPPORTED
-#define PNG_WRITE_pCAL_SUPPORTED
-#define PNG_READ_INVERT_ALPHA_SUPPORTED
-#define PNG_WRITE_TRANSFORMS_SUPPORTED
-#define PNG_READ_sBIT_SUPPORTED
-#define PNG_READ_PACK_SUPPORTED
-#define PNG_WRITE_SWAP_SUPPORTED
-#define PNG_READ_cHRM_SUPPORTED
-#define PNG_WRITE_tIME_SUPPORTED
-#define PNG_READ_INTERLACING_SUPPORTED
-#define PNG_READ_tRNS_SUPPORTED
-#define PNG_WRITE_pHYs_SUPPORTED
-#define PNG_WRITE_INVERT_SUPPORTED
-#define PNG_READ_RGB_TO_GRAY_SUPPORTED
-#define PNG_WRITE_sRGB_SUPPORTED
-#define PNG_READ_oFFs_SUPPORTED
-#define PNG_WRITE_FILLER_SUPPORTED
-#define PNG_WRITE_TEXT_SUPPORTED
-#define PNG_WRITE_SHIFT_SUPPORTED
-#define PNG_PROGRESSIVE_READ_SUPPORTED
-#define PNG_READ_SHIFT_SUPPORTED
-#define PNG_CONVERT_tIME_SUPPORTED
-#define PNG_READ_USER_TRANSFORM_SUPPORTED
-#define PNG_READ_INT_FUNCTIONS_SUPPORTED
-#define PNG_READ_USER_CHUNKS_SUPPORTED
-#define PNG_READ_hIST_SUPPORTED
-#define PNG_READ_16BIT_SUPPORTED
-#define PNG_READ_SWAP_ALPHA_SUPPORTED
-#define PNG_READ_COMPOSITE_NODIV_SUPPORTED
-#define PNG_SEQUENTIAL_READ_SUPPORTED
-#define PNG_READ_BACKGROUND_SUPPORTED
-#define PNG_READ_QUANTIZE_SUPPORTED
-#define PNG_READ_iCCP_SUPPORTED
-#define PNG_READ_STRIP_ALPHA_SUPPORTED
-#define PNG_READ_PACKSWAP_SUPPORTED
-#define PNG_READ_sRGB_SUPPORTED
-#define PNG_WRITE_tEXt_SUPPORTED
-#define PNG_READ_gAMA_SUPPORTED
-#define PNG_READ_pCAL_SUPPORTED
-#define PNG_READ_EXPAND_SUPPORTED
-#define PNG_WRITE_sPLT_SUPPORTED
-#define PNG_READ_SWAP_SUPPORTED
-#define PNG_READ_tIME_SUPPORTED
-#define PNG_READ_pHYs_SUPPORTED
-#define PNG_WRITE_SWAP_ALPHA_SUPPORTED
-#define PNG_TIME_RFC1123_SUPPORTED
-#define PNG_READ_TEXT_SUPPORTED
-#define PNG_WRITE_BGR_SUPPORTED
-#define PNG_USER_CHUNKS_SUPPORTED
-#define PNG_CONSOLE_IO_SUPPORTED
-#define PNG_WRITE_PACK_SUPPORTED
-#define PNG_READ_FILLER_SUPPORTED
-#define PNG_WRITE_bKGD_SUPPORTED
-#define PNG_WRITE_tRNS_SUPPORTED
-#define PNG_READ_sPLT_SUPPORTED
-#define PNG_WRITE_sCAL_SUPPORTED
-#define PNG_WRITE_oFFs_SUPPORTED
-#define PNG_READ_tEXt_SUPPORTED
-#define PNG_WRITE_sBIT_SUPPORTED
-#define PNG_READ_INVERT_SUPPORTED
-#define PNG_READ_16_TO_8_SUPPORTED
-#define PNG_WRITE_cHRM_SUPPORTED
 #define PNG_16BIT_SUPPORTED
-#define PNG_WRITE_USER_TRANSFORM_SUPPORTED
-#define PNG_READ_BGR_SUPPORTED
-#define PNG_WRITE_PACKSWAP_SUPPORTED
-#define PNG_WRITE_INVERT_ALPHA_SUPPORTED
-#define PNG_sCAL_SUPPORTED
-#define PNG_WRITE_zTXt_SUPPORTED
-#define PNG_sBIT_SUPPORTED
-#define PNG_cHRM_SUPPORTED
+#define PNG_ALIGN_MEMORY_SUPPORTED
+#define PNG_BENIGN_ERRORS_SUPPORTED
 #define PNG_bKGD_SUPPORTED
-#define PNG_tRNS_SUPPORTED
-#define PNG_WRITE_iTXt_SUPPORTED
-#define PNG_oFFs_SUPPORTED
-#define PNG_USER_TRANSFORM_PTR_SUPPORTED
+#define PNG_CHECK_cHRM_SUPPORTED
+#define PNG_cHRM_SUPPORTED
+#define PNG_CONSOLE_IO_SUPPORTED
+#define PNG_CONVERT_tIME_SUPPORTED
+#define PNG_EASY_ACCESS_SUPPORTED
+#define PNG_ERROR_TEXT_SUPPORTED
+#define PNG_FIXED_POINT_SUPPORTED
+#define PNG_FLOATING_ARITHMETIC_SUPPORTED
+#define PNG_FLOATING_POINT_SUPPORTED
+#define PNG_gAMA_SUPPORTED
+#define PNG_HANDLE_AS_UNKNOWN_SUPPORTED
 #define PNG_hIST_SUPPORTED
 #define PNG_iCCP_SUPPORTED
-#define PNG_sRGB_SUPPORTED
-#define PNG_READ_zTXt_SUPPORTED
-#define PNG_gAMA_SUPPORTED
-#define PNG_pCAL_SUPPORTED
-#define PNG_CHECK_cHRM_SUPPORTED
-#define PNG_tIME_SUPPORTED
-#define PNG_pHYs_SUPPORTED
-#define PNG_READ_iTXt_SUPPORTED
-#define PNG_TEXT_SUPPORTED
-#define PNG_SAVE_INT_32_SUPPORTED
-#define PNG_sPLT_SUPPORTED
-#define PNG_tEXt_SUPPORTED
-#define PNG_zTXt_SUPPORTED
+#define PNG_INCH_CONVERSIONS_SUPPORTED
+#define PNG_INFO_IMAGE_SUPPORTED
+#define PNG_IO_STATE_SUPPORTED
 #define PNG_iTXt_SUPPORTED
+#define PNG_MNG_FEATURES_SUPPORTED
+#define PNG_oFFs_SUPPORTED
+#define PNG_pCAL_SUPPORTED
+#define PNG_pHYs_SUPPORTED
+#define PNG_POINTER_INDEXING_SUPPORTED
+#define PNG_PROGRESSIVE_READ_SUPPORTED
+#define PNG_READ_16BIT_SUPPORTED
+#define PNG_READ_16_TO_8_SUPPORTED
+#define PNG_READ_ANCILLARY_CHUNKS_SUPPORTED
+#define PNG_READ_BACKGROUND_SUPPORTED
+#define PNG_READ_BGR_SUPPORTED
+#define PNG_READ_bKGD_SUPPORTED
+#define PNG_READ_cHRM_SUPPORTED
+#define PNG_READ_COMPOSITE_NODIV_SUPPORTED
+#define PNG_READ_EXPAND_16_SUPPORTED
+#define PNG_READ_EXPAND_SUPPORTED
+#define PNG_READ_FILLER_SUPPORTED
+#define PNG_READ_gAMA_SUPPORTED
+#define PNG_READ_GAMMA_SUPPORTED
+#define PNG_READ_GRAY_TO_RGB_SUPPORTED
+#define PNG_READ_hIST_SUPPORTED
+#define PNG_READ_iCCP_SUPPORTED
+#define PNG_READ_INTERLACING_SUPPORTED
+#define PNG_READ_INT_FUNCTIONS_SUPPORTED
+#define PNG_READ_INVERT_ALPHA_SUPPORTED
+#define PNG_READ_INVERT_SUPPORTED
+#define PNG_READ_iTXt_SUPPORTED
+#define PNG_READ_oFFs_SUPPORTED
+#define PNG_READ_OPT_PLTE_SUPPORTED
+#define PNG_READ_PACK_SUPPORTED
+#define PNG_READ_PACKSWAP_SUPPORTED
+#define PNG_READ_pCAL_SUPPORTED
+#define PNG_READ_pHYs_SUPPORTED
+#define PNG_READ_QUANTIZE_SUPPORTED
+#define PNG_READ_RGB_TO_GRAY_SUPPORTED
+#define PNG_READ_sBIT_SUPPORTED
+#define PNG_READ_sCAL_SUPPORTED
+#define PNG_READ_SHIFT_SUPPORTED
+#define PNG_READ_sPLT_SUPPORTED
+#define PNG_READ_sRGB_SUPPORTED
+#define PNG_READ_STRIP_ALPHA_SUPPORTED
+#define PNG_READ_SUPPORTED
+#define PNG_READ_SWAP_ALPHA_SUPPORTED
+#define PNG_READ_SWAP_SUPPORTED
+#define PNG_READ_tEXt_SUPPORTED
+#define PNG_READ_TEXT_SUPPORTED
+#define PNG_READ_tIME_SUPPORTED
+#define PNG_READ_TRANSFORMS_SUPPORTED
+#define PNG_READ_tRNS_SUPPORTED
+#define PNG_READ_UNKNOWN_CHUNKS_SUPPORTED
+#define PNG_READ_USER_CHUNKS_SUPPORTED
+#define PNG_READ_USER_TRANSFORM_SUPPORTED
+#define PNG_READ_zTXt_SUPPORTED
+#define PNG_SAVE_INT_32_SUPPORTED
+#define PNG_sBIT_SUPPORTED
+#define PNG_sCAL_SUPPORTED
+#define PNG_SEQUENTIAL_READ_SUPPORTED
+#define PNG_SET_CHUNK_CACHE_LIMIT_SUPPORTED
+#define PNG_SET_CHUNK_MALLOC_LIMIT_SUPPORTED
+#define PNG_SETJMP_SUPPORTED
+#define PNG_SET_USER_LIMITS_SUPPORTED
+#define PNG_sPLT_SUPPORTED
+#define PNG_sRGB_SUPPORTED
+#define PNG_STDIO_SUPPORTED
+#define PNG_tEXt_SUPPORTED
+#define PNG_TEXT_SUPPORTED
+#define PNG_TIME_RFC1123_SUPPORTED
+#define PNG_tIME_SUPPORTED
+#define PNG_tRNS_SUPPORTED
+#define PNG_UNKNOWN_CHUNKS_SUPPORTED
+#define PNG_USER_CHUNKS_SUPPORTED
+#define PNG_USER_LIMITS_SUPPORTED
+#define PNG_USER_MEM_SUPPORTED
+#define PNG_USER_TRANSFORM_INFO_SUPPORTED
+#define PNG_USER_TRANSFORM_PTR_SUPPORTED
+#define PNG_WARNINGS_SUPPORTED
+#define PNG_WRITE_16BIT_SUPPORTED
+#define PNG_WRITE_ANCILLARY_CHUNKS_SUPPORTED
+#define PNG_WRITE_BGR_SUPPORTED
+#define PNG_WRITE_bKGD_SUPPORTED
+#define PNG_WRITE_cHRM_SUPPORTED
+#define PNG_WRITE_FILLER_SUPPORTED
+#define PNG_WRITE_FILTER_SUPPORTED
+#define PNG_WRITE_FLUSH_SUPPORTED
+#define PNG_WRITE_gAMA_SUPPORTED
+#define PNG_WRITE_hIST_SUPPORTED
+#define PNG_WRITE_iCCP_SUPPORTED
+#define PNG_WRITE_INTERLACING_SUPPORTED
+#define PNG_WRITE_INT_FUNCTIONS_SUPPORTED
+#define PNG_WRITE_INVERT_ALPHA_SUPPORTED
+#define PNG_WRITE_INVERT_SUPPORTED
+#define PNG_WRITE_iTXt_SUPPORTED
+#define PNG_WRITE_oFFs_SUPPORTED
+#define PNG_WRITE_PACK_SUPPORTED
+#define PNG_WRITE_PACKSWAP_SUPPORTED
+#define PNG_WRITE_pCAL_SUPPORTED
+#define PNG_WRITE_pHYs_SUPPORTED
+#define PNG_WRITE_sBIT_SUPPORTED
+#define PNG_WRITE_sCAL_SUPPORTED
+#define PNG_WRITE_SHIFT_SUPPORTED
+#define PNG_WRITE_sPLT_SUPPORTED
+#define PNG_WRITE_sRGB_SUPPORTED
+#define PNG_WRITE_SUPPORTED
+#define PNG_WRITE_SWAP_ALPHA_SUPPORTED
+#define PNG_WRITE_SWAP_SUPPORTED
+#define PNG_WRITE_tEXt_SUPPORTED
+#define PNG_WRITE_TEXT_SUPPORTED
+#define PNG_WRITE_tIME_SUPPORTED
+#define PNG_WRITE_TRANSFORMS_SUPPORTED
+#define PNG_WRITE_tRNS_SUPPORTED
+#define PNG_WRITE_UNKNOWN_CHUNKS_SUPPORTED
+#define PNG_WRITE_USER_TRANSFORM_SUPPORTED
+#define PNG_WRITE_WEIGHTED_FILTER_SUPPORTED
+#define PNG_WRITE_zTXt_SUPPORTED
+#define PNG_zTXt_SUPPORTED
+/*#undef PNG_ERROR_NUMBERS_SUPPORTED*/
+/*#undef PNG_READ_16_TO_8_ACCURATE_SCALE_SUPPORTED*/
 /* end of options */
 #endif /* PNGLCONF_H */
--- a/scripts/pngwin.def
+++ b/scripts/pngwin.def
@@ -1,230 +0,0 @@
-;--------------------------------------------------------------
-; LIBPNG module definition file for Windows, WindowsCE and OS/2
-; On OS/2 uncomment lines preceded by ;0S2
-;--------------------------------------------------------------
-
-; If you give the library an explicit name one or other files
-; may need modifying to support the new name on one or more
-; systems.
-LIBRARY
-;OS2 DESCRIPTION "PNG image compression library"
-;OS2 CODE PRELOAD MOVEABLE DISCARDABLE
-
-EXPORTS
-;Version 1.5.0beta55
- png_access_version_number @1
- png_set_sig_bytes @2
- png_sig_cmp @3
- png_create_read_struct @4
- png_create_write_struct @5
- png_get_compression_buffer_size @6
- png_set_compression_buffer_size @7
- png_set_longjmp_fn @8
- png_longjmp @9
- png_reset_zstream @10
- png_create_read_struct_2 @11
- png_create_write_struct_2 @12
- png_write_sig @13
- png_write_chunk @14
- png_write_chunk_start @15
- png_write_chunk_data @16
- png_write_chunk_end @17
- png_create_info_struct @18
- png_info_init_3 @19
- png_write_info_before_PLTE @20
- png_write_info @21
- png_read_info @22
- png_convert_to_rfc1123 @23
- png_convert_from_struct_tm @24
- png_convert_from_time_t @25
- png_set_expand @26
- png_set_expand_gray_1_2_4_to_8 @27
- png_set_palette_to_rgb @28
- png_set_tRNS_to_alpha @29
- png_set_bgr @30
- png_set_gray_to_rgb @31
- png_set_rgb_to_gray @32
- png_set_rgb_to_gray_fixed @33
- png_get_rgb_to_gray_status @34
- png_build_grayscale_palette @35
- png_set_strip_alpha @36
- png_set_swap_alpha @37
- png_set_invert_alpha @38
- png_set_filler @39
- png_set_add_alpha @40
- png_set_swap @41
- png_set_packing @42
- png_set_packswap @43
- png_set_shift @44
- png_set_interlace_handling @45
- png_set_invert_mono @46
- png_set_background @47
- png_set_strip_16 @48
- png_set_quantize @49
- png_set_gamma @50
- png_set_flush @51
- png_write_flush @52
- png_start_read_image @53
- png_read_update_info @54
- png_read_rows @55
- png_read_row @56
- png_read_image @57
- png_write_row @58
- png_write_rows @59
- png_write_image @60
- png_write_end @61
- png_read_end @62
- png_destroy_info_struct @63
- png_destroy_read_struct @64
- png_destroy_write_struct @65
- png_set_crc_action @66
- png_set_filter @67
- png_set_filter_heuristics @68
- png_set_compression_level @69
- png_set_compression_mem_level @70
- png_set_compression_strategy @71
- png_set_compression_window_bits @72
- png_set_compression_method @73
- png_init_io @74
- png_set_error_fn @75
- png_get_error_ptr @76
- png_set_write_fn @77
- png_set_read_fn @78
- png_get_io_ptr @79
- png_set_read_status_fn @80
- png_set_write_status_fn @81
- png_set_mem_fn @82
- png_get_mem_ptr @83
- png_set_read_user_transform_fn @84
- png_set_write_user_transform_fn @85
- png_set_user_transform_info @86
- png_get_user_transform_ptr @87
- png_set_read_user_chunk_fn @88
- png_get_user_chunk_ptr @89
- png_set_progressive_read_fn @90
- png_get_progressive_ptr @91
- png_process_data @92
- png_progressive_combine_row @93
- png_malloc @94
- png_calloc @95
- png_malloc_warn @96
- png_free @97
- png_free_data @98
- png_data_freer @99
- png_malloc_default @100
- png_free_default @101
- png_error @102
- png_chunk_error @103
- png_warning @105
- png_chunk_warning @106
- png_benign_error @107
- png_chunk_benign_error @108
- png_set_benign_errors @109
- png_get_valid @110
- png_get_rowbytes @111
- png_get_rows @112
- png_set_rows @113
- png_get_channels @114
- png_get_image_width @115
- png_get_image_height @116
- png_get_bit_depth @117
- png_get_color_type @118
- png_get_filter_type @119
- png_get_interlace_type @120
- png_get_compression_type @121
- png_get_pixels_per_meter @122
- png_get_x_pixels_per_meter @123
- png_get_y_pixels_per_meter @124
- png_get_pixel_aspect_ratio @125
- png_get_x_offset_pixels @126
- png_get_y_offset_pixels @127
- png_get_x_offset_microns @128
- png_get_y_offset_microns @129
- png_get_signature @130
- png_get_bKGD @131
- png_set_bKGD @132
- png_get_cHRM @133
- png_get_cHRM_fixed @134
- png_set_cHRM @135
- png_set_cHRM_fixed @136
- png_get_gAMA @137
- png_get_gAMA_fixed @138
- png_set_gAMA @139
- png_set_gAMA_fixed @140
- png_get_hIST @141
- png_set_hIST @142
- png_get_IHDR @143
- png_set_IHDR @144
- png_get_oFFs @145
- png_set_oFFs @146
- png_get_pCAL @147
- png_set_pCAL @148
- png_get_pHYs @149
- png_set_pHYs @150
- png_get_PLTE @151
- png_set_PLTE @152
- png_get_sBIT @153
- png_set_sBIT @154
- png_get_sRGB @155
- png_set_sRGB @156
- png_set_sRGB_gAMA_and_cHRM @157
- png_get_iCCP @158
- png_set_iCCP @159
- png_get_sPLT @160
- png_set_sPLT @161
- png_get_text @162
- png_set_text @163
- png_get_tIME @164
- png_set_tIME @165
- png_get_tRNS @166
- png_set_tRNS @167
- png_get_sCAL @168
- png_get_sCAL_s @169
- png_set_sCAL @170
- png_set_sCAL_s @171
- png_set_keep_unknown_chunks @172
- png_handle_as_unknown @173
- png_set_unknown_chunks @174
- png_set_unknown_chunk_location @175
- png_get_unknown_chunks @176
- png_set_invalid @177
- png_read_png @178
- png_write_png @179
- png_get_copyright @180
- png_get_header_ver @181
- png_get_header_version @182
- png_get_libpng_ver @183
- png_permit_mng_features @184
- png_set_user_limits @186
- png_get_user_width_max @187
- png_get_user_height_max @188
- png_set_chunk_cache_max @189
- png_get_chunk_cache_max @190
- png_set_chunk_malloc_max @191
- png_get_chunk_malloc_max @192
- png_get_pixels_per_inch @193
- png_get_x_pixels_per_inch @194
- png_get_y_pixels_per_inch @195
- png_get_x_offset_inches @196
- png_get_y_offset_inches @197
- png_get_pHYs_dpi @198
- png_get_io_state @199
- png_get_io_chunk_name @200
- png_get_uint_32 @201
- png_get_uint_16 @202
- png_get_int_32 @203
- png_get_uint_31 @204
- png_save_uint_32 @205
- png_save_int_32 @206
- png_save_uint_16 @207
- png_set_gamma_fixed @208
- png_set_filter_heuristics_fixed @209
- png_get_pixel_aspect_ratio_fixed @210
- png_get_x_offset_inches_fixed @211
- png_get_y_offset_inches_fixed @212
- png_set_sCAL_fixed @213
- png_get_sCAL_fixed @214
- png_get_num_passes @215
- png_get_num_rows @216
- png_set_background_fixed @217
- png_get_num_cols @218
--- a/scripts/pngwin.dfn
+++ b/scripts/pngwin.dfn
@@ -1,38 +0,0 @@
-
-/* pngwin.dfn - define format of pngwin.def
- *
- * Last changed in libpng version 1.5.0 [(PENDING RELEASE)]
- * Copyright (c) 1998-2010 Glenn Randers-Pehrson
- *
- * This code is released under the libpng license.
- * For conditions of distribution and use, see the disclaimer
- * and license in png.h
- */
-
-#define PNG_EXPORT(type, name, args, attributes, ordinal)\
-	PNG_DEFN_MAGIC- name @ordinal-PNG_DEFN_END
-#define PNG_REMOVED(type, name, args, attributes, ordinal)\
-	PNG_DEFN_MAGIC-; name @ordinal-PNG_DEFN_END
-#define PNG_EXPORT_LAST_ORDINAL(ordinal)\
-	PNG_DEFN_MAGIC-; @ordinal-PNG_DEFN_END
-
-PNG_DEFN_MAGIC-;---------------------------------------------------------------PNG_DEFN_END
-PNG_DEFN_MAGIC-; LIBPNG module definition file for Windows, WindowsCE and OS/2-PNG_DEFN_END
-PNG_DEFN_MAGIC-; On OS/2 uncomment lines preceded by ;0S2-PNG_DEFN_END
-PNG_DEFN_MAGIC-;---------------------------------------------------------------PNG_DEFN_END
-PNG_DEFN_MAGIC--PNG_DEFN_END
-PNG_DEFN_MAGIC-; If you give the library an explicit name one or other files-PNG_DEFN_END
-PNG_DEFN_MAGIC-; may need modifying to support the new name on one or more-PNG_DEFN_END
-PNG_DEFN_MAGIC-; systems.-PNG_DEFN_END
-PNG_DEFN_MAGIC-LIBRARY-PNG_DEFN_END
-PNG_DEFN_MAGIC-;OS2 DESCRIPTION	"PNG image compression library"-PNG_DEFN_END
-PNG_DEFN_MAGIC-;OS2 CODE		PRELOAD MOVEABLE DISCARDABLE-PNG_DEFN_END
-PNG_DEFN_MAGIC--PNG_DEFN_END
-PNG_DEFN_MAGIC-EXPORTS-PNG_DEFN_END
-PNG_DEFN_MAGIC-;Version 1.5.0beta55-PNG_DEFN_END
-
-/* Read the defaults, but use scripts/pnglibconf.h.prebuilt; the 'standard'
- * header file.
- */
-#include "pnglibconf.h.prebuilt"
-#include "../png.h"
--- a/scripts/sym.dfn
+++ b/scripts/sym.dfn
@@ -1,15 +1,15 @@

 /* sym.dfn - define format of libpng.sym
 *
- * Last changed in libpng version 1.5.0 [(PENDING RELEASE)]
- * Copyright (c) 1998-2010 Glenn Randers-Pehrson
+ * Last changed in libpng version 1.5.0 [January 6, 2011]
+ * Copyright (c) 1998-2011 Glenn Randers-Pehrson
 *
 * This code is released under the libpng license.
 * For conditions of distribution and use, see the disclaimer
 * and license in png.h
 */

-#define PNG_EXPORT(type, name, args, attributes, ordinal)\
+#define PNG_EXPORTA(ordinal, type, name, args, attributes)\
 	PNG_DEFN_MAGIC-SYMBOL_PREFIX @@@ name-PNG_DEFN_END

 #include "../png.h"
--- a/scripts/symbols.def
+++ b/scripts/symbols.def
@@ -5,7 +5,7 @@
 LIBRARY

 EXPORTS
-;Version 1.5.0beta55
+;Version 1.5.2rc01
 png_access_version_number @1
 png_set_sig_bytes @2
 png_sig_cmp @3
@@ -220,7 +220,10 @@ EXPORTS
 png_get_y_offset_inches_fixed @212
 png_set_sCAL_fixed @213
 png_get_sCAL_fixed @214
- png_get_num_passes @215
- png_get_num_rows @216
- png_set_background_fixed @217
- png_get_num_cols @218
+ png_set_background_fixed @215
+ png_get_io_chunk_type @216
+ png_get_current_row_number @217
+ png_get_current_pass_number @218
+ png_process_data_pause @219
+ png_process_data_skip @220
+ png_set_expand_16 @221
--- a/scripts/symbols.dfn
+++ b/scripts/symbols.dfn
@@ -1,8 +1,8 @@

 /* symbols.dfn - find all exported symbols
 *
- * Last changed in libpng version 1.5.0 [(PENDING RELEASE)]
- * Copyright (c) 1998-2010 Glenn Randers-Pehrson
+ * Last changed in libpng version 1.5.0 [January 6, 2011]
+ * Copyright (c) 1998-2011 Glenn Randers-Pehrson
 *
 * This code is released under the libpng license.
 * For conditions of distribution and use, see the disclaimer
@@ -16,9 +16,9 @@
 * .dfa file too.
 */

-#define PNG_EXPORT(type, name, args, attributes, ordinal)\
+#define PNG_EXPORTA(ordinal, type, name, args, attributes)\
 	PNG_DEFN_MAGIC-name @ordinal-PNG_DEFN_END
-#define PNG_REMOVED(type, name, args, attributes, ordinal)\
+#define PNG_REMOVED(ordinal, type, name, args, attributes)\
 	PNG_DEFN_MAGIC-; name @ordinal-PNG_DEFN_END
 #define PNG_EXPORT_LAST_ORDINAL(ordinal)\
 	PNG_DEFN_MAGIC-; @ordinal-PNG_DEFN_END
--- a/scripts/vers.dfn
+++ b/scripts/vers.dfn
@@ -1,8 +1,8 @@

 /* vers.dfn - define format of libpng.vers
 *
- * Last changed in libpng version 1.5.0 [(PENDING RELEASE)]
- * Copyright (c) 1998-2010 Glenn Randers-Pehrson
+ * Last changed in libpng version 1.5.0 [January 6, 2011]
+ * Copyright (c) 1998-2011 Glenn Randers-Pehrson
 *
 * This code is released under the libpng license.
 * For conditions of distribution and use, see the disclaimer
@@ -16,7 +16,7 @@
 * substitution within the name, regular C ## joins the pp-tokens,
 * not their final values.
 */
-#define PNG_EXPORT(type, name, args, attributes, ordinal)\
+#define PNG_EXPORTA(ordinal, type, name, args, attributes)\
 	PNG_DEFN_MAGIC- SYMBOL_PREFIX @@@ name;-PNG_DEFN_END

 #define TRAILER PNG_DEFN_MAGIC-local: *; };-PNG_DEFN_END
--- a/test-pngtest.sh
+++ b/test-pngtest.sh
@@ -1,3 +1,8 @@
 #!/bin/sh

-./pngtest ${srcdir}/pngtest.png
+echo "Running tests.  For details see pngtest-log.txt"
+
+echo "============ pngtest pngtest.png ==============" > pngtest-log.txt
+
+echo "Running test-pngtest.sh"
+./pngtest ${srcdir}/pngtest.png >> pngtest-log.txt 2>&1
--- a/test-pngvalid-full.sh
+++ b/test-pngvalid-full.sh
@@ -0,0 +1,23 @@
+#!/bin/sh
+#
+# Run a sequence of gamma tests quietly
+err=0
+
+echo >> pngtest-log.txt
+echo "============ pngvalid-full.sh ==============" >> pngtest-log.txt
+
+echo "Running test-pngvalid-full.sh"
+for gamma in threshold transform sbit 16-to-8
+do
+   if ./pngvalid "--gamma-$gamma" >> pngtest-log.txt 2>&1
+   then
+      echo "  PASS:" pngvalid "--gamma-$gamma"
+   else
+      echo "  FAIL:" pngvalid "--gamma-$gamma"
+      err=1
+   fi
+done
+
+echo
+
+exit $err
--- a/test-pngvalid-simple.sh
+++ b/test-pngvalid-simple.sh
@@ -0,0 +1,30 @@
+#!/bin/sh
+#
+# Run a sequence of tests quietly, without the slow
+# gamma tests
+err=0
+
+echo >> pngtest-log.txt
+echo "============ pngvalid-simple.sh ==============" >> pngtest-log.txt
+echo "Running test-pngvalid-simple.sh"
+# The options to test are:
+#
+# standard tests with and without progressive reading and interlace
+# size images with and without progressive reading
+# transform tests (standard, non-interlaced only)
+#
+for opts in "--standard" "--standard --progressive-read" \
+   "--standard --interlace" "--standard --progressive-read --interlace" \
+   "--size" "--size --progressive-read" \
+   "--transform"
+do
+   if ./pngvalid  $opts >> pngtest-log.txt 2>&1
+   then
+      echo "  PASS:" pngvalid $opts
+   else
+      echo "  FAIL:" pngvalid $opts
+      err=1
+   fi
+done
+
+exit $err