diff options
| author | Kirill Volinsky <mataes2007@gmail.com> | 2013-01-03 14:34:48 +0000 |
|---|---|---|
| committer | Kirill Volinsky <mataes2007@gmail.com> | 2013-01-03 14:34:48 +0000 |
| commit | eb680766d56e815086397361b286fd8055fb5377 (patch) | |
| tree | 7994cdb0d9077f645ba7fd06bdd2cde32cf599d4 /plugins/AdvaImg/src/LibPNG | |
| parent | ec61686c3d96f49eb7f40a4208690a0781d63e29 (diff) | |
FreeImage updated to 3.15.4
removed not used formats
git-svn-id: http://svn.miranda-ng.org/main/trunk@2926 1316c22d-e87f-b044-9b9b-93d7a3e3ba9c
Diffstat (limited to 'plugins/AdvaImg/src/LibPNG')
29 files changed, 3321 insertions, 1329 deletions
diff --git a/plugins/AdvaImg/src/LibPNG/ANNOUNCE b/plugins/AdvaImg/src/LibPNG/ANNOUNCE index e8498a379c..346383d7b9 100644 --- a/plugins/AdvaImg/src/LibPNG/ANNOUNCE +++ b/plugins/AdvaImg/src/LibPNG/ANNOUNCE @@ -1,5 +1,5 @@ -Libpng 1.5.9 - February 18, 2012
+Libpng 1.5.13 - September 27, 2012
This is a public release of libpng, intended for use in production codes.
@@ -8,30 +8,35 @@ Files available for download: Source files with LF line endings (for Unix/Linux) and with a
"configure" script
- libpng-1.5.9.tar.xz (LZMA-compressed, recommended)
- libpng-1.5.9.tar.gz
- libpng-1.5.9.tar.bz2
+ libpng-1.5.13.tar.xz (LZMA-compressed, recommended)
+ libpng-1.5.13.tar.gz
+ libpng-1.5.13.tar.bz2
Source files with CRLF line endings (for Windows), without the
"configure" script
- lpng159.7z (LZMA-compressed, recommended)
- lpng159.zip
+ lpng1513.7z (LZMA-compressed, recommended)
+ lpng1513.zip
Other information:
- libpng-1.5.9-README.txt
- libpng-1.5.9-LICENSE.txt
-
-Changes since the last public release (1.5.8):
-
- Rebuilt configure scripts in the tar distributions.
- Removed two unused definitions from scripts/pnglibconf.h.prebuilt
- Removed some unused arrays (with #ifdef) from png_read_push_finish_row().
- Removed tests for no-longer-used *_EMPTY_PLTE_SUPPORTED from pngstruct.h
- Fixed CVE-2011-3026 buffer overrun bug. Deal more correctly with the test
- on iCCP chunk length. Also removed spurious casts that may hide problems
- on 16-bit systems.
+ libpng-1.5.13-README.txt
+ libpng-1.5.13-LICENSE.txt
+
+Changes since the last public release (1.5.12):
+ Do not compile PNG_DEPRECATED, PNG_ALLOC and PNG_PRIVATE when __GNUC__ < 3.
+ Removed references to png_zalloc() and png_zfree() from the manual.
+ Revised PNG_FP_EXPORT and PNG_FIXED_EXPORT macros to avoid generating
+ lone semicolons (patch ported from libpng-1.6.0beta11).
+ Corrected handling of the image array and the row_pointers array in example.c
+ When png_set_filler is used to strip a filler channel during write, the
+ code prior to 1.5 would ignore the case where the output required an
+ alpha channel or when the output was a palettized PNG. In libpng-1.5 the
+ ignorance was lost and libpng proceeded to strip the channel resulting
+ in a bad (potential memory overwrite) failure later. This reverts
+ the behavior to the pre-1.5 state but issues a warning. libpng-1.6 is
+ expected to issue an error on the erroneous png_set_filler call.
+ Use png_memset() consistently (pngmem.c contained some bare "memset" calls).
Send comments/corrections/commendations to png-mng-implement at lists.sf.net
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diff --git a/plugins/AdvaImg/src/LibPNG/CHANGES b/plugins/AdvaImg/src/LibPNG/CHANGES index fb3a90be8c..d3c0cccc1c 100644 --- a/plugins/AdvaImg/src/LibPNG/CHANGES +++ b/plugins/AdvaImg/src/LibPNG/CHANGES @@ -3803,13 +3803,122 @@ Version 1.5.9beta02 [February 16, 2012] Removed tests for no-longer-used *_EMPTY_PLTE_SUPPORTED from pngstruct.h
Version 1.5.9rc01 [February 17, 2012]
- Fixed CVE-2011-3026 buffer overrun bug. Deal more correctly with the test
- on iCCP chunk length. Also removed spurious casts that may hide problems
- on 16-bit systems.
+ Fixed CVE-2011-3026 buffer overrun bug. This bug was introduced when
+ iCCP chunk support was added at libpng-1.0.6. Deal more correctly with the
+ test on iCCP chunk length. Also removed spurious casts that may hide
+ problems on 16-bit systems.
Version 1.5.9 [February 18, 2012]
No changes.
+Version 1.5.10beta01 [February 24, 2012]
+ Removed two useless #ifdef directives from pngread.c and one from pngrutil.c
+ Always put the CMAKE_LIBRARY in "lib" (removed special WIN32 case).
+ Removed empty vstudio/pngstest directory (Clifford Yapp).
+ Eliminated redundant png_push_read_tEXt|zTXt|iTXt|unknown code from
+ pngpread.c and use the sequential png_handle_tEXt, etc., in pngrutil.c;
+ now that png_ptr->buffer is inaccessible to applications, the special
+ handling is no longer useful.
+ Fixed bug with png_handle_hIST with odd chunk length (Frank Busse).
+ Added PNG_SAFE_LIMITS feature to pnglibconf.dfa and code in pngconf.h
+ to reset the user limits to safe ones if PNG_SAFE_LIMITS is defined.
+ To enable, use "CPPFLAGS=-DPNG_SAFE_LIMITS_SUPPORTED" on the configure
+ command or put "#define PNG_SAFE_LIMITS_SUPPORTED" in pnglibconf.h.
+ Revised the SAFE_LIMITS feature to be the same as the feature in libpng16.
+ Added information about the new limits in the manual.
+
+Version 1.5.10beta02 [February 27, 2012]
+ Updated Makefile.in
+
+Version 1.5.10beta03 [March 6, 2012]
+ Removed unused "current_text" members of png_struct and the png_free()
+ of png_ptr->current_text from pngread.c
+ Added palette-index checking. Issue a png_warning() if an invalid index is
+ found.
+
+Version 1.5.10beta04 [March 10, 2012]
+ Fixed PNG_LIBPNG_BUILD_BASE_TYPE definition.
+ Fixed CMF optimization of non-IDAT compressed chunks, which was added at
+ libpng-1.5.4. It sometimes produced too small of a window.
+
+Version 1.5.10beta05 [March 10, 2012]
+ Reject all iCCP chunks after the first, even if the first one is invalid.
+ Issue a png_benign_error() instead of png_warning() about bad palette index.
+ Fixed an off-by-one error in the palette index checking function.
+ Revised example.c to put text strings in a temporary character array
+ instead of directly assigning string constants to png_textp members.
+ This avoids compiler warnings when -Wwrite-strings is enabled.
+
+Version 1.5.10 [March 29, 2012]
+ Prevent PNG_EXPAND+PNG_SHIFT doing the shift twice.
+ Revised png_set_text_2() to avoid potential memory corruption (fixes
+ CVE-2011-3048, also known as CVE-2012-3425).
+
+Version 1.5.11beta01 [April 28, 2012]
+ Revised scripts/makefile.darwin: use system zlib; remove quotes around
+ architecture list; add missing ppc architecture; add architecture options
+ to shared library link; don't try to create a shared lib based on missing
+ RELEASE variable.
+ Enable png_set_check_for_invalid_index() for both read and write.
+ Removed #ifdef PNG_HANDLE_AS_UNKNOWN_SUPPORTED/#endif in pngpriv.h around
+ declaration of png_handle_unknown().
+ Added -lssp_nonshared in a comment in scripts/makefile.freebsd
+ and changed deprecated NOOBJ and NOPROFILE to NO_OBJ and NO_PROFILE.
+
+Version 1.5.11rc01 [May 23, 2012]
+ No changes.
+
+Version 1.5.11rc02 [May 29, 2012]
+ Fixed some typos in comments.
+ Revised CMakeLists.txt to not attempt to make a symlink under mingw.
+ Added two images to contrib/pngsuite (1-bit and 2-bit transparent grayscale),
+ and renamed three whose names were inconsistent with those in
+ pngsuite/README.txt.
+
+Version 1.5.11rc03 [June 4, 2012]
+ Do not depend upon a GCC feature macro being available for use in generating
+ the linker mapfile symbol prefix.
+ Made fixes for new optimization warnings from gcc 4.7.0. The compiler
+ performed an optimization which is safe but then warned about it.
+ Changing the type of 'palette_number' in pngvalid.c removes the warning.
+
+Version 1.5.11rc04 [June 6, 2012]
+ Improved performance of new do_check_palette_indexes() function.
+
+Version 1.5.11rc05 [June 7, 2012]
+ Don't check palette indexes if num_palette is 0 (as it can be in MNG files).
+
+Version 1.5.11 [June 14, 2012]
+ Include zlib.h in contrib/gregbook and contrib/visupng examples.
+
+Version 1.5.12 [July 11, 2012]
+ Removed scripts/makefile.cegcc from the *.zip and *.7z distributions; it
+ depends on configure, which is not included in those archives.
+ Changed "a+w" to "u+w" in Makefile.in to fix CVE-2012-3386.
+
+Version 1.5.13beta01 [August 8, 2012]
+ Do not compile PNG_DEPRECATED, PNG_ALLOC and PNG_PRIVATE when __GNUC__ < 3.
+ Removed references to png_zalloc() and png_zfree() from the manual.
+ Revised PNG_FP_EXPORT and PNG_FIXED_EXPORT macros to avoid generating
+ lone semicolons (patch ported from libpng-1.6.0beta11).
+
+Version 1.5.13beta02 [September 10, 2012]
+ Corrected handling of the image array and the row_pointers array in example.c
+ When png_set_filler is used to strip a filler channel during write, the
+ code prior to 1.5 would ignore the case where the output required an
+ alpha channel or when the output was a palettized PNG. In libpng-1.5 the
+ ignorance was lost and libpng proceeded to strip the channel resulting
+ in a bad (potential memory overwrite) failure later. This reverts
+ the behavior to the pre-1.5 state but issues a warning. libpng-1.6 is
+ expected to issue an error on the erroneous png_set_filler call.
+ Use png_memset() consistently (pngmem.c contained some bare "memset" calls).
+
+Version 1.5.13rc01 [September 17, 2012]
+ No changes.
+
+Version 1.5.13 [September 27, 2012]
+ No changes.
+
Send comments/corrections/commendations to png-mng-implement at lists.sf.net
(subscription required; visit
https://lists.sourceforge.net/lists/listinfo/png-mng-implement
diff --git a/plugins/AdvaImg/src/LibPNG/KNOWNBUG b/plugins/AdvaImg/src/LibPNG/KNOWNBUG deleted file mode 100644 index f3ddc5245f..0000000000 --- a/plugins/AdvaImg/src/LibPNG/KNOWNBUG +++ /dev/null @@ -1,29 +0,0 @@ -
-Known bugs in libpng version 1.2.43
-
-1. December 4, 2009: The PNG_NO_ERROR_NUMBERS macro was inadvertently
- defined in libpng-1.2.41/pngconf.h, which may cause a problem with
- building a binary-compatible library.
-
- STATUS: This will be fixed in libpng-1.2.42. In the meantime, simply
- delete the definition from line :
-
-2. February 23, 2006: The custom makefiles don't build libpng with -lz.
-
- STATUS: This is a subject of debate. The change will probably be made
- as a part of a major overhaul of the makefiles in libpng version 1.4.0.
-
-3. February 24, 2006: The Makefile generated by the "configure" script
- fails to install symbolic links
- libpng12.so => libpng12.so.0.1.2.9betaN
- that are generated by the custom makefiles.
-
-4. September 4, 2007: There is a report that pngtest crashes on MacOS 10.
-
- STATUS: workarounds are
- 1) Compile without optimization (crashes are observed with
- -arch i386 and -O2 or -O3, using gcc-4.0.1).
- 2) Compile pngtest.c with PNG_DEBUG defined (the bug goes away if
- you try to look at it).
- 3) Ignore the crash. The library itself seems to be OK.
-
diff --git a/plugins/AdvaImg/src/LibPNG/LICENSE b/plugins/AdvaImg/src/LibPNG/LICENSE index 0c927409ac..853fb2cc24 100644 --- a/plugins/AdvaImg/src/LibPNG/LICENSE +++ b/plugins/AdvaImg/src/LibPNG/LICENSE @@ -10,8 +10,8 @@ this sentence. This code is released under the libpng license.
-libpng versions 1.2.6, August 15, 2004, through 1.5.9, February 18, 2012, are
-Copyright (c) 2004, 2006-2011 Glenn Randers-Pehrson, and are
+libpng versions 1.2.6, August 15, 2004, through 1.5.13, September 27, 2012, are
+Copyright (c) 2004, 2006-2012 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
-February 18, 2012
+September 27, 2012
diff --git a/plugins/AdvaImg/src/LibPNG/README b/plugins/AdvaImg/src/LibPNG/README index c648a5ad78..5afeae8c45 100644 --- a/plugins/AdvaImg/src/LibPNG/README +++ b/plugins/AdvaImg/src/LibPNG/README @@ -1,4 +1,4 @@ -README for libpng version 1.5.9 - February 18, 2012 (shared library 15.0)
+README for libpng version 1.5.13 - September 27, 2012 (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.
diff --git a/plugins/AdvaImg/src/LibPNG/Y2KINFO b/plugins/AdvaImg/src/LibPNG/Y2KINFO deleted file mode 100644 index 7776d83732..0000000000 --- a/plugins/AdvaImg/src/LibPNG/Y2KINFO +++ /dev/null @@ -1,55 +0,0 @@ - Y2K compliance in libpng:
- =========================
-
- February 25, 2010
-
- Since the PNG Development group is an ad-hoc body, we can't make
- an official declaration.
-
- This is your unofficial assurance that libpng from version 0.71 and
- upward through 1.2.43 are Y2K compliant. It is my belief that earlier
- versions were also Y2K compliant.
-
- Libpng only has three year fields. One is a 2-byte unsigned integer
- that will hold years up to 65535. The other two hold the date in text
- format, and will hold years up to 9999.
-
- The integer is
- "png_uint_16 year" in png_time_struct.
-
- The strings are
- "png_charp time_buffer" in png_struct and
- "near_time_buffer", which is a local character string in png.c.
-
- There are seven time-related functions:
-
- png_convert_to_rfc_1123() in png.c
- (formerly png_convert_to_rfc_1152() in error)
- png_convert_from_struct_tm() in pngwrite.c, called in pngwrite.c
- png_convert_from_time_t() in pngwrite.c
- png_get_tIME() in pngget.c
- png_handle_tIME() in pngrutil.c, called in pngread.c
- png_set_tIME() in pngset.c
- png_write_tIME() in pngwutil.c, called in pngwrite.c
-
- All appear to handle dates properly in a Y2K environment. The
- png_convert_from_time_t() function calls gmtime() to convert from system
- clock time, which returns (year - 1900), which we properly convert to
- the full 4-digit year. There is a possibility that applications using
- libpng are not passing 4-digit years into the png_convert_to_rfc_1123()
- function, or that they are incorrectly passing only a 2-digit year
- instead of "year - 1900" into the png_convert_from_struct_tm() function,
- but this is not under our control. The libpng documentation has always
- stated that it works with 4-digit years, and the APIs have been
- documented as such.
-
- The tIME chunk itself is also Y2K compliant. It uses a 2-byte unsigned
- integer to hold the year, and can hold years as large as 65535.
-
- zlib, upon which libpng depends, is also Y2K compliant. It contains
- no date-related code.
-
-
- Glenn Randers-Pehrson
- libpng maintainer
- PNG Development Group
diff --git a/plugins/AdvaImg/src/LibPNG/configure b/plugins/AdvaImg/src/LibPNG/configure index 9da0f74eca..218dddd913 100644 --- a/plugins/AdvaImg/src/LibPNG/configure +++ b/plugins/AdvaImg/src/LibPNG/configure @@ -1,19 +1,19 @@ echo "
- There is no \"configure\" script in this distribution of
- libpng-1.5.9.
+ There is no \"configure\" script in this distribution (*.zip or *.7z) of
+ libpng-1.5.13.
Instead, please copy the appropriate makefile for your system from the
\"scripts\" directory. Read the INSTALL file for more details.
Update, July 2004: you can get a \"configure\" based distribution
from the libpng distribution sites. Download the file
- libpng-1.5.9.tar.gz, libpng-1.5.9.tar.xz, or libpng-1.5.9.tar.bz2
+ libpng-1.5.13.tar.gz, libpng-1.5.13.tar.xz, or libpng-1.5.13.tar.bz2
If the line endings in the files look funny, which is likely to be the
case if you were trying to run \"configure\" on a Linux machine, you may
wish to get the other distribution of libpng. It is available in both
- tar.gz/tar.xz (UNIX style line endings) and .7z/.zip (DOS style line
- endings) formats.
+ tar.gz/tar.xz (UNIX style line endings, with \"configure\") and .7z/.zip
+ (DOS style line endings, without \"configure\") formats.
"
diff --git a/plugins/AdvaImg/src/LibPNG/example.c b/plugins/AdvaImg/src/LibPNG/example.c new file mode 100644 index 0000000000..04241ef416 --- /dev/null +++ b/plugins/AdvaImg/src/LibPNG/example.c @@ -0,0 +1,879 @@ +
+#if 0 /* in case someone actually tries to compile this */
+
+/* example.c - an example of using libpng
+ * Last changed in libpng 1.5.10 [March 8, 2012]
+ * Maintained 1998-2012 Glenn Randers-Pehrson
+ * Maintained 1996, 1997 Andreas Dilger
+ * Written 1995, 1996 Guy Eric Schalnat, Group 42, Inc.
+ */
+
+/* This is an example of how to use libpng to read and write PNG files.
+ * The file libpng-manual.txt is much more verbose then this. If you have not
+ * read it, do so first. This was designed to be a starting point of an
+ * implementation. This is not officially part of libpng, is hereby placed
+ * in the public domain, and therefore does not require a copyright notice.
+ * To the extent possible under law, the authors have waived all copyright and
+ * related or neighboring rights to this file.
+ *
+ * This file does not currently compile, because it is missing certain
+ * parts, like allocating memory to hold an image. You will have to
+ * supply these parts to get it to compile. For an example of a minimal
+ * working PNG reader/writer, see pngtest.c, included in this distribution;
+ * see also the programs in the contrib directory.
+ */
+
+#define _POSIX_SOURCE 1 /* libpng and zlib are POSIX-compliant. You may
+ * change this if your application uses non-POSIX
+ * extensions. */
+
+#include "png.h"
+
+ /* The png_jmpbuf() macro, used in error handling, became available in
+ * libpng version 1.0.6. If you want to be able to run your code with older
+ * versions of libpng, you must define the macro yourself (but only if it
+ * is not already defined by libpng!).
+ */
+
+#ifndef png_jmpbuf
+# define png_jmpbuf(png_ptr) ((png_ptr)->png_jmpbuf)
+#endif
+
+/* Check to see if a file is a PNG file using png_sig_cmp(). png_sig_cmp()
+ * returns zero if the image is a PNG and nonzero if it isn't a PNG.
+ *
+ * The function check_if_png() shown here, but not used, returns nonzero (true)
+ * if the file can be opened and is a PNG, 0 (false) otherwise.
+ *
+ * If this call is successful, and you are going to keep the file open,
+ * you should call png_set_sig_bytes(png_ptr, PNG_BYTES_TO_CHECK); once
+ * you have created the png_ptr, so that libpng knows your application
+ * has read that many bytes from the start of the file. Make sure you
+ * don't call png_set_sig_bytes() with more than 8 bytes read or give it
+ * an incorrect number of bytes read, or you will either have read too
+ * many bytes (your fault), or you are telling libpng to read the wrong
+ * number of magic bytes (also your fault).
+ *
+ * Many applications already read the first 2 or 4 bytes from the start
+ * of the image to determine the file type, so it would be easiest just
+ * to pass the bytes to png_sig_cmp() or even skip that if you know
+ * you have a PNG file, and call png_set_sig_bytes().
+ */
+#define PNG_BYTES_TO_CHECK 4
+int check_if_png(char *file_name, FILE **fp)
+{
+ char buf[PNG_BYTES_TO_CHECK];
+
+ /* Open the prospective PNG file. */
+ if ((*fp = fopen(file_name, "rb")) == NULL)
+ return 0;
+
+ /* Read in some of the signature bytes */
+ if (fread(buf, 1, PNG_BYTES_TO_CHECK, *fp) != PNG_BYTES_TO_CHECK)
+ return 0;
+
+ /* Compare the first PNG_BYTES_TO_CHECK bytes of the signature.
+ Return nonzero (true) if they match */
+
+ return(!png_sig_cmp(buf, (png_size_t)0, PNG_BYTES_TO_CHECK));
+}
+
+/* Read a PNG file. You may want to return an error code if the read
+ * fails (depending upon the failure). There are two "prototypes" given
+ * here - one where we are given the filename, and we need to open the
+ * file, and the other where we are given an open file (possibly with
+ * some or all of the magic bytes read - see comments above).
+ */
+#ifdef open_file /* prototype 1 */
+void read_png(char *file_name) /* We need to open the file */
+{
+ png_structp png_ptr;
+ png_infop info_ptr;
+ unsigned int sig_read = 0;
+ png_uint_32 width, height;
+ int bit_depth, color_type, interlace_type;
+ FILE *fp;
+
+ if ((fp = fopen(file_name, "rb")) == NULL)
+ return (ERROR);
+
+#else no_open_file /* prototype 2 */
+void read_png(FILE *fp, unsigned int sig_read) /* File is already open */
+{
+ png_structp png_ptr;
+ png_infop info_ptr;
+ png_uint_32 width, height;
+ int bit_depth, color_type, interlace_type;
+#endif no_open_file /* Only use one prototype! */
+
+ /* Create and initialize the png_struct with the desired error handler
+ * functions. If you want to use the default stderr and longjump method,
+ * you can supply NULL for the last three parameters. We also supply the
+ * the compiler header file version, so that we know if the application
+ * was compiled with a compatible version of the library. REQUIRED
+ */
+ png_ptr = png_create_read_struct(PNG_LIBPNG_VER_STRING,
+ png_voidp user_error_ptr, user_error_fn, user_warning_fn);
+
+ if (png_ptr == NULL)
+ {
+ fclose(fp);
+ return (ERROR);
+ }
+
+ /* Allocate/initialize the memory for image information. REQUIRED. */
+ info_ptr = png_create_info_struct(png_ptr);
+ if (info_ptr == NULL)
+ {
+ fclose(fp);
+ png_destroy_read_struct(&png_ptr, NULL, NULL);
+ return (ERROR);
+ }
+
+ /* Set error handling if you are using the setjmp/longjmp method (this is
+ * the normal method of doing things with libpng). REQUIRED unless you
+ * set up your own error handlers in the png_create_read_struct() earlier.
+ */
+
+ if (setjmp(png_jmpbuf(png_ptr)))
+ {
+ /* Free all of the memory associated with the png_ptr and info_ptr */
+ png_destroy_read_struct(&png_ptr, &info_ptr, NULL);
+ fclose(fp);
+ /* If we get here, we had a problem reading the file */
+ return (ERROR);
+ }
+
+ /* One of the following I/O initialization methods is REQUIRED */
+#ifdef streams /* PNG file I/O method 1 */
+ /* Set up the input control if you are using standard C streams */
+ png_init_io(png_ptr, fp);
+
+#else no_streams /* PNG file I/O method 2 */
+ /* If you are using replacement read functions, instead of calling
+ * png_init_io() here you would call:
+ */
+ png_set_read_fn(png_ptr, (void *)user_io_ptr, user_read_fn);
+ /* where user_io_ptr is a structure you want available to the callbacks */
+#endif no_streams /* Use only one I/O method! */
+
+ /* If we have already read some of the signature */
+ png_set_sig_bytes(png_ptr, sig_read);
+
+#ifdef hilevel
+ /*
+ * If you have enough memory to read in the entire image at once,
+ * and you need to specify only transforms that can be controlled
+ * with one of the PNG_TRANSFORM_* bits (this presently excludes
+ * quantizing, filling, setting background, and doing gamma
+ * adjustment), then you can read the entire image (including
+ * pixels) into the info structure with this call:
+ */
+ png_read_png(png_ptr, info_ptr, png_transforms, NULL);
+
+#else
+ /* OK, you're doing it the hard way, with the lower-level functions */
+
+ /* The call to png_read_info() gives us all of the information from the
+ * PNG file before the first IDAT (image data chunk). REQUIRED
+ */
+ png_read_info(png_ptr, info_ptr);
+
+ png_get_IHDR(png_ptr, info_ptr, &width, &height, &bit_depth, &color_type,
+ &interlace_type, NULL, NULL);
+
+ /* Set up the data transformations you want. Note that these are all
+ * optional. Only call them if you want/need them. Many of the
+ * transformations only work on specific types of images, and many
+ * are mutually exclusive.
+ */
+
+ /* Tell libpng to strip 16 bit/color files down to 8 bits/color.
+ * Use accurate scaling if it's available, otherwise just chop off the
+ * low byte.
+ */
+#ifdef PNG_READ_SCALE_16_TO_8_SUPPORTED
+ png_set_scale_16(png_ptr);
+#else
+ png_set_strip_16(png_ptr);
+#endif
+
+ /* Strip alpha bytes from the input data without combining with the
+ * background (not recommended).
+ */
+ png_set_strip_alpha(png_ptr);
+
+ /* Extract multiple pixels with bit depths of 1, 2, and 4 from a single
+ * byte into separate bytes (useful for paletted and grayscale images).
+ */
+ png_set_packing(png_ptr);
+
+ /* Change the order of packed pixels to least significant bit first
+ * (not useful if you are using png_set_packing). */
+ png_set_packswap(png_ptr);
+
+ /* Expand paletted colors into true RGB triplets */
+ if (color_type == PNG_COLOR_TYPE_PALETTE)
+ png_set_palette_to_rgb(png_ptr);
+
+ /* Expand grayscale images to the full 8 bits from 1, 2, or 4 bits/pixel */
+ if (color_type == PNG_COLOR_TYPE_GRAY && bit_depth < 8)
+ png_set_expand_gray_1_2_4_to_8(png_ptr);
+
+ /* Expand paletted or RGB images with transparency to full alpha channels
+ * so the data will be available as RGBA quartets.
+ */
+ if (png_get_valid(png_ptr, info_ptr, PNG_INFO_tRNS))
+ png_set_tRNS_to_alpha(png_ptr);
+
+ /* Set the background color to draw transparent and alpha images over.
+ * It is possible to set the red, green, and blue components directly
+ * for paletted images instead of supplying a palette index. Note that
+ * even if the PNG file supplies a background, you are not required to
+ * use it - you should use the (solid) application background if it has one.
+ */
+
+ png_color_16 my_background, *image_background;
+
+ if (png_get_bKGD(png_ptr, info_ptr, &image_background))
+ png_set_background(png_ptr, image_background,
+ PNG_BACKGROUND_GAMMA_FILE, 1, 1.0);
+ else
+ png_set_background(png_ptr, &my_background,
+ PNG_BACKGROUND_GAMMA_SCREEN, 0, 1.0);
+
+ /* Some suggestions as to how to get a screen gamma value
+ *
+ * Note that screen gamma is the display_exponent, which includes
+ * the CRT_exponent and any correction for viewing conditions
+ */
+ if (/* We have a user-defined screen gamma value */)
+ {
+ screen_gamma = user-defined screen_gamma;
+ }
+ /* This is one way that applications share the same screen gamma value */
+ else if ((gamma_str = getenv("SCREEN_GAMMA")) != NULL)
+ {
+ screen_gamma = atof(gamma_str);
+ }
+ /* If we don't have another value */
+ else
+ {
+ screen_gamma = 2.2; /* A good guess for a PC monitor in a dimly
+ lit room */
+ screen_gamma = 1.7 or 1.0; /* A good guess for Mac systems */
+ }
+
+ /* Tell libpng to handle the gamma conversion for you. The final call
+ * is a good guess for PC generated images, but it should be configurable
+ * by the user at run time by the user. It is strongly suggested that
+ * your application support gamma correction.
+ */
+
+ int intent;
+
+ if (png_get_sRGB(png_ptr, info_ptr, &intent))
+ png_set_gamma(png_ptr, screen_gamma, 0.45455);
+ else
+ {
+ double image_gamma;
+ if (png_get_gAMA(png_ptr, info_ptr, &image_gamma))
+ png_set_gamma(png_ptr, screen_gamma, image_gamma);
+ else
+ png_set_gamma(png_ptr, screen_gamma, 0.45455);
+ }
+
+#ifdef PNG_READ_QUANTIZE_SUPPORTED
+ /* Quantize RGB files down to 8 bit palette or reduce palettes
+ * to the number of colors available on your screen.
+ */
+ if (color_type & PNG_COLOR_MASK_COLOR)
+ {
+ int num_palette;
+ png_colorp palette;
+
+ /* This reduces the image to the application supplied palette */
+ if (/* We have our own palette */)
+ {
+ /* An array of colors to which the image should be quantized */
+ png_color std_color_cube[MAX_SCREEN_COLORS];
+
+ png_set_quantize(png_ptr, std_color_cube, MAX_SCREEN_COLORS,
+ MAX_SCREEN_COLORS, NULL, 0);
+ }
+ /* This reduces the image to the palette supplied in the file */
+ else if (png_get_PLTE(png_ptr, info_ptr, &palette, &num_palette))
+ {
+ png_uint_16p histogram = NULL;
+
+ png_get_hIST(png_ptr, info_ptr, &histogram);
+
+ png_set_quantize(png_ptr, palette, num_palette,
+ max_screen_colors, histogram, 0);
+ }
+ }
+#endif /* PNG_READ_QUANTIZE_SUPPORTED */
+
+ /* Invert monochrome files to have 0 as white and 1 as black */
+ png_set_invert_mono(png_ptr);
+
+ /* If you want to shift the pixel values from the range [0,255] or
+ * [0,65535] to the original [0,7] or [0,31], or whatever range the
+ * colors were originally in:
+ */
+ if (png_get_valid(png_ptr, info_ptr, PNG_INFO_sBIT))
+ {
+ png_color_8p sig_bit_p;
+
+ png_get_sBIT(png_ptr, info_ptr, &sig_bit_p);
+ png_set_shift(png_ptr, sig_bit_p);
+ }
+
+ /* Flip the RGB pixels to BGR (or RGBA to BGRA) */
+ if (color_type & PNG_COLOR_MASK_COLOR)
+ png_set_bgr(png_ptr);
+
+ /* Swap the RGBA or GA data to ARGB or AG (or BGRA to ABGR) */
+ png_set_swap_alpha(png_ptr);
+
+ /* Swap bytes of 16 bit files to least significant byte first */
+ png_set_swap(png_ptr);
+
+ /* Add filler (or alpha) byte (before/after each RGB triplet) */
+ png_set_filler(png_ptr, 0xff, PNG_FILLER_AFTER);
+
+#ifdef PNG_READ_INTERLACING_SUPPORTED
+ /* Turn on interlace handling. REQUIRED if you are not using
+ * png_read_image(). To see how to handle interlacing passes,
+ * see the png_read_row() method below:
+ */
+ number_passes = png_set_interlace_handling(png_ptr);
+#else
+ number_passes = 1;
+#endif /* PNG_READ_INTERLACING_SUPPORTED */
+
+
+ /* 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 (ie you selected such a transform above).
+ */
+ png_read_update_info(png_ptr, info_ptr);
+
+ /* Allocate the memory to hold the image using the fields of info_ptr. */
+
+ /* The easiest way to read the image: */
+ png_bytep row_pointers[height];
+
+ /* Clear the pointer array */
+ for (row = 0; row < height; row++)
+ row_pointers[row] = NULL;
+
+ for (row = 0; row < height; row++)
+ row_pointers[row] = png_malloc(png_ptr, png_get_rowbytes(png_ptr,
+ info_ptr));
+
+ /* Now it's time to read the image. One of these methods is REQUIRED */
+#ifdef entire /* Read the entire image in one go */
+ png_read_image(png_ptr, row_pointers);
+
+#else no_entire /* Read the image one or more scanlines at a time */
+ /* The other way to read images - deal with interlacing: */
+
+ for (pass = 0; pass < number_passes; pass++)
+ {
+#ifdef single /* Read the image a single row at a time */
+ for (y = 0; y < height; y++)
+ {
+ png_read_rows(png_ptr, &row_pointers[y], NULL, 1);
+ }
+
+#else no_single /* Read the image several rows at a time */
+ for (y = 0; y < height; y += number_of_rows)
+ {
+#ifdef sparkle /* Read the image using the "sparkle" effect. */
+ png_read_rows(png_ptr, &row_pointers[y], NULL,
+ number_of_rows);
+#else no_sparkle /* Read the image using the "rectangle" effect */
+ png_read_rows(png_ptr, NULL, &row_pointers[y],
+ number_of_rows);
+#endif no_sparkle /* Use only one of these two methods */
+ }
+
+ /* If you want to display the image after every pass, do so here */
+#endif no_single /* Use only one of these two methods */
+ }
+#endif no_entire /* Use only one of these two methods */
+
+ /* Read rest of file, and get additional chunks in info_ptr - REQUIRED */
+ png_read_end(png_ptr, info_ptr);
+#endif hilevel
+
+ /* At this point you have read the entire image */
+
+ /* Clean up after the read, and free any memory allocated - REQUIRED */
+ png_destroy_read_struct(&png_ptr, &info_ptr, NULL);
+
+ /* Close the file */
+ fclose(fp);
+
+ /* That's it */
+ return (OK);
+}
+
+/* Progressively read a file */
+
+int
+initialize_png_reader(png_structp *png_ptr, png_infop *info_ptr)
+{
+ /* Create and initialize the png_struct with the desired error handler
+ * functions. If you want to use the default stderr and longjump method,
+ * you can supply NULL for the last three parameters. We also check that
+ * the library version is compatible in case we are using dynamically
+ * linked libraries.
+ */
+ *png_ptr = png_create_read_struct(PNG_LIBPNG_VER_STRING,
+ png_voidp user_error_ptr, user_error_fn, user_warning_fn);
+
+ if (*png_ptr == NULL)
+ {
+ *info_ptr = NULL;
+ return (ERROR);
+ }
+
+ *info_ptr = png_create_info_struct(png_ptr);
+
+ if (*info_ptr == NULL)
+ {
+ png_destroy_read_struct(png_ptr, info_ptr, NULL);
+ return (ERROR);
+ }
+
+ if (setjmp(png_jmpbuf((*png_ptr))))
+ {
+ png_destroy_read_struct(png_ptr, info_ptr, NULL);
+ return (ERROR);
+ }
+
+ /* This one's new. You will need to provide all three
+ * function callbacks, even if you aren't using them all.
+ * If you aren't using all functions, you can specify NULL
+ * parameters. Even when all three functions are NULL,
+ * you need to call png_set_progressive_read_fn().
+ * These functions shouldn't be dependent on global or
+ * static variables if you are decoding several images
+ * simultaneously. You should store stream specific data
+ * in a separate struct, given as the second parameter,
+ * and retrieve the pointer from inside the callbacks using
+ * the function png_get_progressive_ptr(png_ptr).
+ */
+ png_set_progressive_read_fn(*png_ptr, (void *)stream_data,
+ info_callback, row_callback, end_callback);
+
+ return (OK);
+}
+
+int
+process_data(png_structp *png_ptr, png_infop *info_ptr,
+ png_bytep buffer, png_uint_32 length)
+{
+ if (setjmp(png_jmpbuf((*png_ptr))))
+ {
+ /* Free the png_ptr and info_ptr memory on error */
+ png_destroy_read_struct(png_ptr, info_ptr, NULL);
+ return (ERROR);
+ }
+
+ /* This one's new also. Simply give it chunks of data as
+ * they arrive from the data stream (in order, of course).
+ * On segmented machines, don't give it any more than 64K.
+ * The library seems to run fine with sizes of 4K, although
+ * you can give it much less if necessary (I assume you can
+ * give it chunks of 1 byte, but I haven't tried with less
+ * than 256 bytes yet). When this function returns, you may
+ * want to display any rows that were generated in the row
+ * callback, if you aren't already displaying them there.
+ */
+ png_process_data(*png_ptr, *info_ptr, buffer, length);
+ return (OK);
+}
+
+info_callback(png_structp png_ptr, png_infop info)
+{
+ /* Do any setup here, including setting any of the transformations
+ * mentioned in the Reading PNG files section. For now, you _must_
+ * call either png_start_read_image() or png_read_update_info()
+ * after all the transformations are set (even if you don't set
+ * any). You may start getting rows before png_process_data()
+ * returns, so this is your last chance to prepare for that.
+ */
+}
+
+row_callback(png_structp png_ptr, png_bytep new_row,
+ png_uint_32 row_num, int pass)
+{
+ /*
+ * This function is called for every row in the image. If the
+ * image is interlaced, and you turned on the interlace handler,
+ * this function will be called for every row in every pass.
+ *
+ * In this function you will receive a pointer to new row data from
+ * libpng called new_row that is to replace a corresponding row (of
+ * the same data format) in a buffer allocated by your application.
+ *
+ * The new row data pointer "new_row" may be NULL, indicating there is
+ * no new data to be replaced (in cases of interlace loading).
+ *
+ * If new_row is not NULL then you need to call
+ * png_progressive_combine_row() to replace the corresponding row as
+ * shown below:
+ */
+
+ /* Get pointer to corresponding row in our
+ * PNG read buffer.
+ */
+ png_bytep old_row = ((png_bytep *)our_data)[row_num];
+
+#ifdef PNG_READ_INTERLACING_SUPPORTED
+ /* If both rows are allocated then copy the new row
+ * data to the corresponding row data.
+ */
+ if ((old_row != NULL) && (new_row != NULL))
+ png_progressive_combine_row(png_ptr, old_row, new_row);
+
+ /*
+ * The rows and passes are called in order, so you don't really
+ * need the row_num and pass, but I'm supplying them because it
+ * may make your life easier.
+ *
+ * For the non-NULL rows of interlaced images, you must call
+ * png_progressive_combine_row() passing in the new row and the
+ * old row, as demonstrated above. You can call this function for
+ * NULL rows (it will just return) and for non-interlaced images
+ * (it just does the png_memcpy for you) if it will make the code
+ * easier. Thus, you can just do this for all cases:
+ */
+
+ png_progressive_combine_row(png_ptr, old_row, new_row);
+
+ /* where old_row is what was displayed for previous rows. Note
+ * that the first pass (pass == 0 really) will completely cover
+ * the old row, so the rows do not have to be initialized. After
+ * the first pass (and only for interlaced images), you will have
+ * to pass the current row as new_row, and the function will combine
+ * the old row and the new row.
+ */
+#endif /* PNG_READ_INTERLACING_SUPPORTED */
+}
+
+end_callback(png_structp png_ptr, png_infop info)
+{
+ /* This function is called when the whole image has been read,
+ * including any chunks after the image (up to and including
+ * the IEND). You will usually have the same info chunk as you
+ * had in the header, although some data may have been added
+ * to the comments and time fields.
+ *
+ * Most people won't do much here, perhaps setting a flag that
+ * marks the image as finished.
+ */
+}
+
+/* Write a png file */
+void write_png(char *file_name /* , ... other image information ... */)
+{
+ FILE *fp;
+ png_structp png_ptr;
+ png_infop info_ptr;
+ png_colorp palette;
+
+ /* Open the file */
+ fp = fopen(file_name, "wb");
+ if (fp == NULL)
+ return (ERROR);
+
+ /* Create and initialize the png_struct with the desired error handler
+ * functions. If you want to use the default stderr and longjump method,
+ * you can supply NULL for the last three parameters. We also check that
+ * the library version is compatible with the one used at compile time,
+ * in case we are using dynamically linked libraries. REQUIRED.
+ */
+ png_ptr = png_create_write_struct(PNG_LIBPNG_VER_STRING,
+ png_voidp user_error_ptr, user_error_fn, user_warning_fn);
+
+ if (png_ptr == NULL)
+ {
+ fclose(fp);
+ return (ERROR);
+ }
+
+ /* Allocate/initialize the image information data. REQUIRED */
+ info_ptr = png_create_info_struct(png_ptr);
+ if (info_ptr == NULL)
+ {
+ fclose(fp);
+ png_destroy_write_struct(&png_ptr, NULL);
+ return (ERROR);
+ }
+
+ /* Set error handling. REQUIRED if you aren't supplying your own
+ * error handling functions in the png_create_write_struct() call.
+ */
+ if (setjmp(png_jmpbuf(png_ptr)))
+ {
+ /* If we get here, we had a problem writing the file */
+ fclose(fp);
+ png_destroy_write_struct(&png_ptr, &info_ptr);
+ return (ERROR);
+ }
+
+ /* One of the following I/O initialization functions is REQUIRED */
+
+#ifdef streams /* I/O initialization method 1 */
+ /* Set up the output control if you are using standard C streams */
+ png_init_io(png_ptr, fp);
+
+#else no_streams /* I/O initialization method 2 */
+ /* If you are using replacement write functions, instead of calling
+ * png_init_io() here you would call
+ */
+ png_set_write_fn(png_ptr, (void *)user_io_ptr, user_write_fn,
+ user_IO_flush_function);
+ /* where user_io_ptr is a structure you want available to the callbacks */
+#endif no_streams /* Only use one initialization method */
+
+#ifdef hilevel
+ /* This is the easy way. Use it if you already have all the
+ * image info living in the structure. You could "|" many
+ * PNG_TRANSFORM flags into the png_transforms integer here.
+ */
+ png_write_png(png_ptr, info_ptr, png_transforms, NULL);
+
+#else
+ /* This is the hard way */
+
+ /* Set the image information here. Width and height are up to 2^31,
+ * bit_depth is one of 1, 2, 4, 8, or 16, but valid values also depend on
+ * the color_type selected. color_type is one of PNG_COLOR_TYPE_GRAY,
+ * PNG_COLOR_TYPE_GRAY_ALPHA, PNG_COLOR_TYPE_PALETTE, PNG_COLOR_TYPE_RGB,
+ * or PNG_COLOR_TYPE_RGB_ALPHA. interlace is either PNG_INTERLACE_NONE or
+ * PNG_INTERLACE_ADAM7, and the compression_type and filter_type MUST
+ * currently be PNG_COMPRESSION_TYPE_BASE and PNG_FILTER_TYPE_BASE. REQUIRED
+ */
+ png_set_IHDR(png_ptr, info_ptr, width, height, bit_depth, PNG_COLOR_TYPE_???,
+ PNG_INTERLACE_????, PNG_COMPRESSION_TYPE_BASE, PNG_FILTER_TYPE_BASE);
+
+ /* Set the palette if there is one. REQUIRED for indexed-color images */
+ palette = (png_colorp)png_malloc(png_ptr, PNG_MAX_PALETTE_LENGTH
+ * png_sizeof(png_color));
+ /* ... Set palette colors ... */
+ png_set_PLTE(png_ptr, info_ptr, palette, PNG_MAX_PALETTE_LENGTH);
+ /* You must not free palette here, because png_set_PLTE only makes a link to
+ * the palette that you malloced. Wait until you are about to destroy
+ * the png structure.
+ */
+
+ /* Optional significant bit (sBIT) chunk */
+ png_color_8 sig_bit;
+
+ /* If we are dealing with a grayscale image then */
+ sig_bit.gray = true_bit_depth;
+
+ /* Otherwise, if we are dealing with a color image then */
+ sig_bit.red = true_red_bit_depth;
+ sig_bit.green = true_green_bit_depth;
+ sig_bit.blue = true_blue_bit_depth;
+
+ /* If the image has an alpha channel then */
+ sig_bit.alpha = true_alpha_bit_depth;
+
+ png_set_sBIT(png_ptr, info_ptr, &sig_bit);
+
+
+ /* Optional gamma chunk is strongly suggested if you have any guess
+ * as to the correct gamma of the image.
+ */
+ png_set_gAMA(png_ptr, info_ptr, gamma);
+
+ /* Optionally write comments into the image */
+ {
+ png_text text_ptr[3];
+
+ char key0[]="Title";
+ char text0[]="Mona Lisa";
+ text_ptr[0].key = key0;
+ text_ptr[0].text = text0;
+ text_ptr[0].compression = PNG_TEXT_COMPRESSION_NONE;
+ text_ptr[0].itxt_length = 0;
+ text_ptr[0].lang = NULL;
+ text_ptr[0].lang_key = NULL;
+
+ char key1[]="Author";
+ char text1[]="Leonardo DaVinci";
+ text_ptr[1].key = key1;
+ text_ptr[1].text = text1;
+ text_ptr[1].compression = PNG_TEXT_COMPRESSION_NONE;
+ text_ptr[1].itxt_length = 0;
+ text_ptr[1].lang = NULL;
+ text_ptr[1].lang_key = NULL;
+
+ char key2[]="Description";
+ char text2[]="<long text>";
+ text_ptr[2].key = key2;
+ text_ptr[2].text = text2;
+ text_ptr[2].compression = PNG_TEXT_COMPRESSION_zTXt;
+ text_ptr[2].itxt_length = 0;
+ text_ptr[2].lang = NULL;
+ text_ptr[2].lang_key = NULL;
+
+ png_set_text(write_ptr, write_info_ptr, text_ptr, 3);
+ }
+
+ /* Other optional chunks like cHRM, bKGD, tRNS, tIME, oFFs, pHYs */
+
+ /* Note that if sRGB is present the gAMA and cHRM chunks must be ignored
+ * on read and, if your application chooses to write them, they must
+ * be written in accordance with the sRGB profile
+ */
+
+ /* Write the file header information. REQUIRED */
+ png_write_info(png_ptr, info_ptr);
+
+ /* If you want, you can write the info in two steps, in case you need to
+ * write your private chunk ahead of PLTE:
+ *
+ * png_write_info_before_PLTE(write_ptr, write_info_ptr);
+ * write_my_chunk();
+ * png_write_info(png_ptr, info_ptr);
+ *
+ * However, given the level of known- and unknown-chunk support in 1.2.0
+ * and up, this should no longer be necessary.
+ */
+
+ /* Once we write out the header, the compression type on the text
+ * chunks gets changed to PNG_TEXT_COMPRESSION_NONE_WR or
+ * PNG_TEXT_COMPRESSION_zTXt_WR, so it doesn't get written out again
+ * at the end.
+ */
+
+ /* Set up the transformations you want. Note that these are
+ * all optional. Only call them if you want them.
+ */
+
+ /* Invert monochrome pixels */
+ png_set_invert_mono(png_ptr);
+
+ /* Shift the pixels up to a legal bit depth and fill in
+ * as appropriate to correctly scale the image.
+ */
+ png_set_shift(png_ptr, &sig_bit);
+
+ /* Pack pixels into bytes */
+ png_set_packing(png_ptr);
+
+ /* Swap location of alpha bytes from ARGB to RGBA */
+ png_set_swap_alpha(png_ptr);
+
+ /* Get rid of filler (OR ALPHA) bytes, pack XRGB/RGBX/ARGB/RGBA into
+ * RGB (4 channels -> 3 channels). The second parameter is not used.
+ */
+ png_set_filler(png_ptr, 0, PNG_FILLER_BEFORE);
+
+ /* Flip BGR pixels to RGB */
+ png_set_bgr(png_ptr);
+
+ /* Swap bytes of 16-bit files to most significant byte first */
+ png_set_swap(png_ptr);
+
+ /* Swap bits of 1, 2, 4 bit packed pixel formats */
+ png_set_packswap(png_ptr);
+
+ /* Turn on interlace handling if you are not using png_write_image() */
+ if (interlacing)
+ number_passes = png_set_interlace_handling(png_ptr);
+
+ else
+ number_passes = 1;
+
+ /* The easiest way to write the image (you may have a different memory
+ * layout, however, so choose what fits your needs best). You need to
+ * use the first method if you aren't handling interlacing yourself.
+ */
+ png_uint_32 k, height, width;
+
+ /* In this example, "image" is a one-dimensional array of bytes */
+ png_byte image[height*width*bytes_per_pixel];
+
+ png_bytep row_pointers[height];
+
+ if (height > PNG_UINT_32_MAX/png_sizeof(png_bytep))
+ png_error (png_ptr, "Image is too tall to process in memory");
+
+ /* Set up pointers into your "image" byte array */
+ for (k = 0; k < height; k++)
+ row_pointers[k] = image + k*width*bytes_per_pixel;
+
+ /* One of the following output methods is REQUIRED */
+
+#ifdef entire /* Write out the entire image data in one call */
+ png_write_image(png_ptr, row_pointers);
+
+ /* The other way to write the image - deal with interlacing */
+
+#else no_entire /* Write out the image data by one or more scanlines */
+
+ /* The number of passes is either 1 for non-interlaced images,
+ * or 7 for interlaced images.
+ */
+ for (pass = 0; pass < number_passes; pass++)
+ {
+ /* Write a few rows at a time. */
+ png_write_rows(png_ptr, &row_pointers[first_row], number_of_rows);
+
+ /* If you are only writing one row at a time, this works */
+ for (y = 0; y < height; y++)
+ png_write_rows(png_ptr, &row_pointers[y], 1);
+ }
+#endif no_entire /* Use only one output method */
+
+ /* You can write optional chunks like tEXt, zTXt, and tIME at the end
+ * as well. Shouldn't be necessary in 1.2.0 and up as all the public
+ * chunks are supported and you can use png_set_unknown_chunks() to
+ * register unknown chunks into the info structure to be written out.
+ */
+
+ /* It is REQUIRED to call this to finish writing the rest of the file */
+ png_write_end(png_ptr, info_ptr);
+#endif hilevel
+
+ /* If you png_malloced a palette, free it here (don't free info_ptr->palette,
+ * as recommended in versions 1.0.5m and earlier of this example; if
+ * libpng mallocs info_ptr->palette, libpng will free it). If you
+ * allocated it with malloc() instead of png_malloc(), use free() instead
+ * of png_free().
+ */
+ png_free(png_ptr, palette);
+ palette = NULL;
+
+ /* Similarly, if you png_malloced any data that you passed in with
+ * png_set_something(), such as a hist or trans array, free it here,
+ * when you can be sure that libpng is through with it.
+ */
+ png_free(png_ptr, trans);
+ trans = NULL;
+ /* Whenever you use png_free() it is a good idea to set the pointer to
+ * NULL in case your application inadvertently tries to png_free() it
+ * again. When png_free() sees a NULL it returns without action, thus
+ * avoiding the double-free security problem.
+ */
+
+ /* Clean up after the write, and free any memory allocated */
+ png_destroy_write_struct(&png_ptr, &info_ptr);
+
+ /* Close the file */
+ fclose(fp);
+
+ /* That's it */
+ return (OK);
+}
+
+#endif /* if 0 */
diff --git a/plugins/AdvaImg/src/LibPNG/libpng.txt b/plugins/AdvaImg/src/LibPNG/libpng-manual.txt index f1eefbbb37..82afe70641 100644 --- a/plugins/AdvaImg/src/LibPNG/libpng.txt +++ b/plugins/AdvaImg/src/LibPNG/libpng-manual.txt @@ -1,9 +1,9 @@ -libpng.txt - A description on how to use and modify libpng
+Libpng-manual.txt - A description on how to use and modify libpng
- libpng version 1.4.3 - June 26, 2010
+ libpng version 1.5.13 - September 27, 2012
Updated and distributed by Glenn Randers-Pehrson
<glennrp at users.sourceforge.net>
- Copyright (c) 1998-2009 Glenn Randers-Pehrson
+ Copyright (c) 1998-2012 Glenn Randers-Pehrson
This document is released under the libpng license.
For conditions of distribution and use, see the disclaimer
@@ -11,9 +11,9 @@ libpng.txt - A description on how to use and modify libpng Based on:
- libpng versions 0.97, January 1998, through 1.4.3 - June 26, 2010
+ libpng versions 0.97, January 1998, through 1.5.13 - September 27, 2012
Updated and distributed by Glenn Randers-Pehrson
- Copyright (c) 1998-2009 Glenn Randers-Pehrson
+ Copyright (c) 1998-2012 Glenn Randers-Pehrson
libpng 1.0 beta 6 version 0.96 May 28, 1997
Updated and distributed by Andreas Dilger
@@ -99,34 +99,203 @@ same instance of a structure. II. Structures
There are two main structures that are important to libpng, png_struct
-and png_info. The first, png_struct, is an internal structure that
-will not, for the most part, be used by a user except as the first
-variable passed to every libpng function call.
+and png_info. Both are internal structures that are no longer exposed
+in the libpng interface (as of libpng 1.5.0).
The png_info structure is designed to provide information about the
PNG file. At one time, the fields of png_info were intended to be
directly accessible to the user. However, this tended to cause problems
with applications using dynamically loaded libraries, and as a result
a set of interface functions for png_info (the png_get_*() and png_set_*()
-functions) was developed. The fields of png_info are still available for
-older applications, but it is suggested that applications use the new
-interfaces if at all possible.
-
-Applications that do make direct access to the members of png_struct (except
-for png_ptr->jmpbuf) must be recompiled whenever the library is updated,
-and applications that make direct access to the members of png_info must
-be recompiled if they were compiled or loaded with libpng version 1.0.6,
-in which the members were in a different order. In version 1.0.7, the
-members of the png_info structure reverted to the old order, as they were
-in versions 0.97c through 1.0.5. Starting with version 2.0.0, both
-structures are going to be hidden, and the contents of the structures will
-only be accessible through the png_get/png_set functions.
+functions) was developed, and direct access to the png_info fields was
+deprecated..
+
+The png_struct structure is the object used by the library to decode a
+single image. As of 1.5.0 this structure is also not exposed.
+
+Almost all libpng APIs require a pointer to a png_struct as the first argument.
+Many (in particular the png_set and png_get APIs) also require a pointer
+to png_info as the second argument. Some application visible macros
+defined in png.h designed for basic data access (reading and writing
+integers in the PNG format) don't take a png_info pointer, but it's almost
+always safe to assume that a (png_struct*) has to be passed to call an API
+function.
+
+You can have more than one png_info structure associated with an image,
+as illustrated in pngtest.c, one for information valid prior to the
+IDAT chunks and another (called "end_info" below) for things after them.
The png.h header file is an invaluable reference for programming with libpng.
And while I'm on the topic, make sure you include the libpng header file:
#include <png.h>
+and also (as of libpng-1.5.0) the zlib header file, if you need it:
+
+#include <zlib.h>
+
+Types
+
+The png.h header file defines a number of integral types used by the
+APIs. Most of these are fairly obvious; for example types corresponding
+to integers of particular sizes and types for passing color values.
+
+One exception is how non-integral numbers are handled. For application
+convenience most APIs that take such numbers have C (double) arguments;
+however, internally PNG, and libpng, use 32 bit signed integers and encode
+the value by multiplying by 100,000. As of libpng 1.5.0 a convenience
+macro PNG_FP_1 is defined in png.h along with a type (png_fixed_point)
+which is simply (png_int_32).
+
+All APIs that take (double) arguments also have a matching API that
+takes the corresponding fixed point integer arguments. The fixed point
+API has the same name as the floating point one with "_fixed" appended.
+The actual range of values permitted in the APIs is frequently less than
+the full range of (png_fixed_point) (-21474 to +21474). When APIs require
+a non-negative argument the type is recorded as png_uint_32 above. Consult
+the header file and the text below for more information.
+
+Special care must be take with sCAL chunk handling because the chunk itself
+uses non-integral values encoded as strings containing decimal floating point
+numbers. See the comments in the header file.
+
+Configuration
+
+The main header file function declarations are frequently protected by C
+preprocessing directives of the form:
+
+ #ifdef PNG_feature_SUPPORTED
+ declare-function
+ #endif
+ ...
+ #ifdef PNG_feature_SUPPORTED
+ use-function
+ #endif
+
+The library can be built without support for these APIs, although a
+standard build will have all implemented APIs. Application programs
+should check the feature macros before using an API for maximum
+portability. From libpng 1.5.0 the feature macros set during the build
+of libpng are recorded in the header file "pnglibconf.h" and this file
+is always included by png.h.
+
+If you don't need to change the library configuration from the default, skip to
+the next section ("Reading").
+
+Notice that some of the makefiles in the 'scripts' directory and (in 1.5.0) all
+of the build project files in the 'projects' directory simply copy
+scripts/pnglibconf.h.prebuilt to pnglibconf.h. This means that these build
+systems do not permit easy auto-configuration of the library - they only
+support the default configuration.
+
+The easiest way to make minor changes to the libpng configuration when
+auto-configuration is supported is to add definitions to the command line
+using (typically) CPPFLAGS. For example:
+
+CPPFLAGS=-DPNG_NO_FLOATING_ARITHMETIC
+
+will change the internal libpng math implementation for gamma correction and
+other arithmetic calculations to fixed point, avoiding the need for fast
+floating point support. The result can be seen in the generated pnglibconf.h -
+make sure it contains the changed feature macro setting.
+
+If you need to make more extensive configuration changes - more than one or two
+feature macro settings - you can either add -DPNG_USER_CONFIG to the build
+command line and put a list of feature macro settings in pngusr.h or you can set
+DFA_XTRA (a makefile variable) to a file containing the same information in the
+form of 'option' settings.
+
+A. Changing pnglibconf.h
+
+A variety of methods exist to build libpng. Not all of these support
+reconfiguration of pnglibconf.h. To reconfigure pnglibconf.h it must either be
+rebuilt from scripts/pnglibconf.dfa using awk or it must be edited by hand.
+
+Hand editing is achieved by copying scripts/pnglibconf.h.prebuilt to
+pnglibconf.h and changing the lines defining the supported features, paying
+very close attention to the 'option' information in scripts/pnglibconf.dfa
+that describes those features and their requirements. This is easy to get
+wrong.
+
+B. Configuration using DFA_XTRA
+
+Rebuilding from pnglibconf.dfa is easy if a functioning 'awk', or a later
+variant such as 'nawk' or 'gawk', is available. The configure build will
+automatically find an appropriate awk and build pnglibconf.h.
+The scripts/pnglibconf.mak file contains a set of make rules for doing the
+same thing if configure is not used, and many of the makefiles in the scripts
+directory use this approach.
+
+When rebuilding simply write a new file containing changed options and set
+DFA_XTRA to the name of this file. This causes the build to append the new file
+to the end of scripts/pnglibconf.dfa. The pngusr.dfa file should contain lines
+of the following forms:
+
+everything = off
+
+This turns all optional features off. Include it at the start of pngusr.dfa to
+make it easier to build a minimal configuration. You will need to turn at least
+some features on afterward to enable either reading or writing code, or both.
+
+option feature on
+option feature off
+
+Enable or disable a single feature. This will automatically enable other
+features required by a feature that is turned on or disable other features that
+require a feature which is turned off. Conflicting settings will cause an error
+message to be emitted by awk.
+
+setting feature default value
+
+Changes the default value of setting 'feature' to 'value'. There are a small
+number of settings listed at the top of pnglibconf.h, they are documented in the
+source code. Most of these values have performance implications for the library
+but most of them have no visible effect on the API. Some can also be overridden
+from the API.
+
+This method of building a customized pnglibconf.h is illustrated in
+contrib/pngminim/*. See the "$(PNGCONF):" target in the makefile and
+pngusr.dfa in these directories.
+
+C. Configuration using PNG_USR_CONFIG
+
+If -DPNG_USR_CONFIG is added to the CFLAGS when pnglibconf.h is built the file
+pngusr.h will automatically be included before the options in
+scripts/pnglibconf.dfa are processed. Your pngusr.h file should contain only
+macro definitions turning features on or off or setting settings.
+
+Apart from the global setting "everything = off" all the options listed above
+can be set using macros in pngusr.h:
+
+#define PNG_feature_SUPPORTED
+
+is equivalent to:
+
+option feature on
+
+#define PNG_NO_feature
+
+is equivalent to:
+
+option feature off
+
+#define PNG_feature value
+
+is equivalent to:
+
+setting feature default value
+
+Notice that in both cases, pngusr.dfa and pngusr.h, the contents of the
+pngusr file you supply override the contents of scripts/pnglibconf.dfa
+
+If confusing or incomprehensible behavior results it is possible to
+examine the intermediate file pnglibconf.dfn to find the full set of
+dependency information for each setting and option. Simply locate the
+feature in the file and read the C comments that precede it.
+
+This method is also illustrated in the contrib/pngminim/* makefiles and
+pngusr.h.
+
III. Reading
We'll now walk you through the possible functions to call when reading
@@ -162,13 +331,15 @@ Customizing libpng. FILE *fp = fopen(file_name, "rb");
if (!fp)
{
- return (ERROR);
+ return (ERROR);
}
+
fread(header, 1, number, fp);
is_png = !png_sig_cmp(header, 0, number);
+
if (!is_png)
{
- return (NOT_PNG);
+ return (NOT_PNG);
}
@@ -184,33 +355,27 @@ The structure allocation functions quietly return NULL if they fail to create the structure, so your application should check for that.
png_structp png_ptr = png_create_read_struct
- (PNG_LIBPNG_VER_STRING, (png_voidp)user_error_ptr,
+ (PNG_LIBPNG_VER_STRING, (png_voidp)user_error_ptr,
user_error_fn, user_warning_fn);
+
if (!png_ptr)
- return (ERROR);
+ return (ERROR);
png_infop info_ptr = png_create_info_struct(png_ptr);
+
if (!info_ptr)
{
- png_destroy_read_struct(&png_ptr,
+ png_destroy_read_struct(&png_ptr,
(png_infopp)NULL, (png_infopp)NULL);
- return (ERROR);
- }
-
- png_infop end_info = png_create_info_struct(png_ptr);
- if (!end_info)
- {
- png_destroy_read_struct(&png_ptr, &info_ptr,
- (png_infopp)NULL);
- return (ERROR);
+ return (ERROR);
}
If you want to use your own memory allocation routines,
-define PNG_USER_MEM_SUPPORTED and use
+use a libpng that was built with PNG_USER_MEM_SUPPORTED defined, and use
png_create_read_struct_2() instead of png_create_read_struct():
png_structp png_ptr = png_create_read_struct_2
- (PNG_LIBPNG_VER_STRING, (png_voidp)user_error_ptr,
+ (PNG_LIBPNG_VER_STRING, (png_voidp)user_error_ptr,
user_error_fn, user_warning_fn, (png_voidp)
user_mem_ptr, user_malloc_fn, user_free_fn);
@@ -222,7 +387,7 @@ handling and memory alloc/free functions. When libpng encounters an error, it expects to longjmp back
to your routine. Therefore, you will need to call setjmp and pass
your png_jmpbuf(png_ptr). If you read the file from different
-routines, you will need to update the jmpbuf field every time you enter
+routines, you will need to update the longjmp buffer every time you enter
a new routine that will call a png_*() function.
See your documentation of setjmp/longjmp for your compiler for more
@@ -234,12 +399,15 @@ free any memory. if (setjmp(png_jmpbuf(png_ptr)))
{
- png_destroy_read_struct(&png_ptr, &info_ptr,
+ png_destroy_read_struct(&png_ptr, &info_ptr,
&end_info);
- fclose(fp);
- return (ERROR);
+ fclose(fp);
+ return (ERROR);
}
+Pass (png_infopp)NULL instead of &end_info if you didn't create
+an end_info structure.
+
If you would rather avoid the complexity of setjmp/longjmp issues,
you can compile libpng with PNG_NO_SETJMP, in which case
errors will result in a call to PNG_ABORT() which defaults to abort().
@@ -273,12 +441,37 @@ where the default size is 8192 bytes. Note that the buffer size is changed immediately and the buffer is reallocated immediately,
instead of setting a flag to be acted upon later.
+If you want CRC errors to be handled in a different manner than
+the default, use
+
+ png_set_crc_action(png_ptr, crit_action, ancil_action);
+
+The values for png_set_crc_action() say how libpng is to handle CRC errors in
+ancillary and critical chunks, and whether to use the data contained
+therein. Note that it is impossible to "discard" data in a critical
+chunk.
+
+Choices for (int) crit_action are
+ PNG_CRC_DEFAULT 0 error/quit
+ PNG_CRC_ERROR_QUIT 1 error/quit
+ PNG_CRC_WARN_USE 3 warn/use data
+ PNG_CRC_QUIET_USE 4 quiet/use data
+ PNG_CRC_NO_CHANGE 5 use the current value
+
+Choices for (int) ancil_action are
+ PNG_CRC_DEFAULT 0 error/quit
+ PNG_CRC_ERROR_QUIT 1 error/quit
+ PNG_CRC_WARN_DISCARD 2 warn/discard data
+ PNG_CRC_WARN_USE 3 warn/use data
+ PNG_CRC_QUIET_USE 4 quiet/use data
+ PNG_CRC_NO_CHANGE 5 use the current value
+
Setting up callback code
You can set up a callback function to handle any unknown chunks in the
input stream. You must supply the function
- read_chunk_callback(png_ptr ptr,
+ read_chunk_callback(png_structp png_ptr,
png_unknown_chunkp chunk);
{
/* The unknown chunk structure contains your
@@ -324,8 +517,8 @@ called after each row has been read, which you can use to control a progress meter or the like. It's demonstrated in pngtest.c.
You must supply a function
- void read_row_callback(png_ptr ptr, png_uint_32 row,
- int pass);
+ void read_row_callback(png_structp png_ptr,
+ png_uint_32 row, int pass);
{
/* put your code here */
}
@@ -336,6 +529,19 @@ To inform libpng about your function, use png_set_read_status_fn(png_ptr, read_row_callback);
+When this function is called the row has already been completely processed and
+the 'row' and 'pass' refer to the next row to be handled. For the
+non-interlaced case the row that was just handled is simply one less than the
+passed in row number, and pass will always be 0. For the interlaced case the
+same applies unless the row value is 0, in which case the row just handled was
+the last one from one of the preceding passes. Because interlacing may skip a
+pass you cannot be sure that the preceding pass is just 'pass-1', if you really
+need to know what the last pass is record (row,pass) from the callback and use
+the last recorded value each time.
+
+As with the user transform you can find the output row using the
+PNG_ROW_FROM_PASS_ROW macro.
+
Unknown-chunk handling
Now you get to set the way the library processes unknown chunks in the
@@ -351,14 +557,17 @@ chunk types. To change this, you can call: 1: ignore; do not keep
2: keep only if safe-to-copy
3: keep even if unsafe-to-copy
+
You can use these definitions:
PNG_HANDLE_CHUNK_AS_DEFAULT 0
PNG_HANDLE_CHUNK_NEVER 1
PNG_HANDLE_CHUNK_IF_SAFE 2
PNG_HANDLE_CHUNK_ALWAYS 3
+
chunk_list - list of chunks affected (a byte string,
five bytes per chunk, NULL or '\0' if
num_chunks is 0)
+
num_chunks - number of chunks affected; if 0, all
unknown chunks are affected. If nonzero,
only the chunks in the list are affected
@@ -370,6 +579,8 @@ according to the "keep" directive. If a chunk is named in successive instances of png_set_keep_unknown_chunks(), the final instance will
take precedence. The IHDR and IEND chunks should not be named in
chunk_list; if they are, libpng will process them normally anyway.
+If you know that your application will never make use of some particular
+chunks, use PNG_HANDLE_CHUNK_NEVER (or 1) as demonstrated below.
Here is an example of the usage of png_set_keep_unknown_chunks(),
where the private "vpAg" chunk will later be processed by a user chunk
@@ -394,8 +605,10 @@ callback function: #if defined(PNG_UNKNOWN_CHUNKS_SUPPORTED)
/* ignore all unknown chunks: */
png_set_keep_unknown_chunks(read_ptr, 1, NULL, 0);
+
/* except for vpAg: */
png_set_keep_unknown_chunks(read_ptr, 2, vpAg, 1);
+
/* also ignore unused known chunks: */
png_set_keep_unknown_chunks(read_ptr, 1, unused_chunks,
(int)sizeof(unused_chunks)/5);
@@ -408,7 +621,7 @@ large as 2^31-1 (0x7fffffff), or about 2.147 billion rows and columns. Since very few applications really need to process such large images,
we have imposed an arbitrary 1-million limit on rows and columns.
Larger images will be rejected immediately with a png_error() call. If
-you wish to override this limit, you can use
+you wish to change this limit, you can use
png_set_user_limits(png_ptr, width_max, height_max);
@@ -418,6 +631,10 @@ anyway because of potential buffer overflow conditions). You should put this statement after you create the PNG structure and
before calling png_read_info(), png_read_png(), or png_process_data().
+
+When writing a PNG datastream, put this statement before calling
+png_write_info() or png_write_png().
+
If you need to retrieve the limits that are being applied, use
width_max = png_get_user_width_max(png_ptr);
@@ -448,6 +665,242 @@ and you can retrieve the limit with Any chunks that would cause either of these limits to be exceeded will
be ignored.
+Information about your system
+
+If you intend to display the PNG or to incorporate it in other image data you
+need to tell libpng information about your display or drawing surface so that
+libpng can convert the values in the image to match the display.
+
+From libpng-1.5.4 this information can be set before reading the PNG file
+header. In earlier versions png_set_gamma() existed but behaved incorrectly if
+called before the PNG file header had been read and png_set_alpha_mode() did not
+exist.
+
+If you need to support versions prior to libpng-1.5.4 test the version number
+as illustrated below using "PNG_LIBPNG_VER >= 10504" and follow the procedures
+described in the appropriate manual page.
+
+You give libpng the encoding expected by your system expressed as a 'gamma'
+value. You can also specify a default encoding for the PNG file in
+case the required information is missing from the file. By default libpng
+assumes that the PNG data matches your system, to keep this default call:
+
+ png_set_gamma(png_ptr, screen_gamma, 1/screen_gamma/*file gamma*/);
+
+or you can use the fixed point equivalent:
+
+ png_set_gamma_fixed(png_ptr, PNG_FP_1*screen_gamma, PNG_FP_1/screen_gamma);
+
+If you don't know the gamma for your system it is probably 2.2 - a good
+approximation to the IEC standard for display systems (sRGB). If images are
+too contrasty or washed out you got the value wrong - check your system
+documentation!
+
+Many systems permit the system gamma to be changed via a lookup table in the
+display driver, a few systems, including older Macs, change the response by
+default. As of 1.5.4 three special values are available to handle common
+situations:
+
+ PNG_DEFAULT_sRGB: Indicates that the system conforms to the IEC 61966-2-1
+ standard. This matches almost all systems.
+ PNG_GAMMA_MAC_18: Indicates that the system is an older (pre Mac OS 10.6)
+ Apple Macintosh system with the default settings.
+ PNG_GAMMA_LINEAR: Just the fixed point value for 1.0 - indicates that the
+ system expects data with no gamma encoding.
+
+You would use the linear (unencoded) value if you need to process the pixel
+values further because this avoids the need to decode and reencode each
+component value whenever arithmetic is performed. A lot of graphics software
+uses linear values for this reason, often with higher precision component values
+to preserve overall accuracy.
+
+The second thing you may need to tell libpng about is how your system handles
+alpha channel information. Some, but not all, PNG files contain an alpha
+channel. To display these files correctly you need to compose the data onto a
+suitable background, as described in the PNG specification.
+
+Libpng only supports composing onto a single color (using png_set_background;
+see below). Otherwise you must do the composition yourself and, in this case,
+you may need to call png_set_alpha_mode:
+
+ #if PNG_LIBPNG_VER >= 10504
+ png_set_alpha_mode(png_ptr, mode, screen_gamma);
+ #else
+ png_set_gamma(png_ptr, screen_gamma, 1.0/screen_gamma);
+ #endif
+
+The screen_gamma value is the same as the argument to png_set_gamma; however,
+how it affects the output depends on the mode. png_set_alpha_mode() sets the
+file gamma default to 1/screen_gamma, so normally you don't need to call
+png_set_gamma. If you need different defaults call png_set_gamma() before
+png_set_alpha_mode() - if you call it after it will override the settings made
+by png_set_alpha_mode().
+
+The mode is as follows:
+
+ PNG_ALPHA_PNG: The data is encoded according to the PNG specification. Red,
+green and blue, or gray, components are gamma encoded color
+values and are not premultiplied by the alpha value. The
+alpha value is a linear measure of the contribution of the
+pixel to the corresponding final output pixel.
+
+You should normally use this format if you intend to perform
+color correction on the color values; most, maybe all, color
+correction software has no handling for the alpha channel and,
+anyway, the math to handle pre-multiplied component values is
+unnecessarily complex.
+
+Before you do any arithmetic on the component values you need
+to remove the gamma encoding and multiply out the alpha
+channel. See the PNG specification for more detail. It is
+important to note that when an image with an alpha channel is
+scaled, linear encoded, pre-multiplied component values must
+be used!
+
+The remaining modes assume you don't need to do any further color correction or
+that if you do, your color correction software knows all about alpha (it
+probably doesn't!)
+
+ PNG_ALPHA_STANDARD: The data libpng produces
+is encoded in the standard way
+assumed by most correctly written graphics software.
+The gamma encoding will be removed by libpng and the
+linear component values will be pre-multiplied by the
+alpha channel.
+
+With this format the final image must be re-encoded to
+match the display gamma before the image is displayed.
+If your system doesn't do that, yet still seems to
+perform arithmetic on the pixels without decoding them,
+it is broken - check out the modes below.
+
+With PNG_ALPHA_STANDARD libpng always produces linear
+component values, whatever screen_gamma you supply. The
+screen_gamma value is, however, used as a default for
+the file gamma if the PNG file has no gamma information.
+
+If you call png_set_gamma() after png_set_alpha_mode() you
+will override the linear encoding. Instead the
+pre-multiplied pixel values will be gamma encoded but
+the alpha channel will still be linear. This may
+actually match the requirements of some broken software,
+but it is unlikely.
+
+While linear 8-bit data is often used it has
+insufficient precision for any image with a reasonable
+dynamic range. To avoid problems, and if your software
+supports it, use png_set_expand_16() to force all
+components to 16 bits.
+
+ PNG_ALPHA_OPTIMIZED: This mode is the same
+as PNG_ALPHA_STANDARD except that
+completely opaque pixels are gamma encoded according to
+the screen_gamma value. Pixels with alpha less than 1.0
+will still have linear components.
+
+Use this format if you have control over your
+compositing software and so don't do other arithmetic
+(such as scaling) on the data you get from libpng. Your
+compositing software can simply copy opaque pixels to
+the output but still has linear values for the
+non-opaque pixels.
+
+In normal compositing, where the alpha channel encodes
+partial pixel coverage (as opposed to broad area
+translucency), the inaccuracies of the 8-bit
+representation of non-opaque pixels are irrelevant.
+
+You can also try this format if your software is broken;
+it might look better.
+
+ PNG_ALPHA_BROKEN: This is PNG_ALPHA_STANDARD;
+however, all component values,
+including the alpha channel are gamma encoded. This is
+an appropriate format to try if your software, or more
+likely hardware, is totally broken, i.e., if it performs
+linear arithmetic directly on gamma encoded values.
+
+In most cases of broken software or hardware the bug in the final display
+manifests as a subtle halo around composited parts of the image. You may not
+even perceive this as a halo; the composited part of the image may simply appear
+separate from the background, as though it had been cut out of paper and pasted
+on afterward.
+
+If you don't have to deal with bugs in software or hardware, or if you can fix
+them, there are three recommended ways of using png_set_alpha_mode():
+
+ png_set_alpha_mode(png_ptr, PNG_ALPHA_PNG,
+ screen_gamma);
+
+You can do color correction on the result (libpng does not currently
+support color correction internally). When you handle the alpha channel
+you need to undo the gamma encoding and multiply out the alpha.
+
+ png_set_alpha_mode(png_ptr, PNG_ALPHA_STANDARD,
+ screen_gamma);
+ png_set_expand_16(png_ptr);
+
+If you are using the high level interface, don't call png_set_expand_16();
+instead pass PNG_TRANSFORM_EXPAND_16 to the interface.
+
+With this mode you can't do color correction, but you can do arithmetic,
+including composition and scaling, on the data without further processing.
+
+ png_set_alpha_mode(png_ptr, PNG_ALPHA_OPTIMIZED,
+ screen_gamma);
+
+You can avoid the expansion to 16-bit components with this mode, but you
+lose the ability to scale the image or perform other linear arithmetic.
+All you can do is compose the result onto a matching output. Since this
+mode is libpng-specific you also need to write your own composition
+software.
+
+If you don't need, or can't handle, the alpha channel you can call
+png_set_background() to remove it by compositing against a fixed color. Don't
+call png_set_strip_alpha() to do this - it will leave spurious pixel values in
+transparent parts of this image.
+
+ png_set_background(png_ptr, &background_color,
+ PNG_BACKGROUND_GAMMA_SCREEN, 0, 1);
+
+The background_color is an RGB or grayscale value according to the data format
+libpng will produce for you. Because you don't yet know the format of the PNG
+file, if you call png_set_background at this point you must arrange for the
+format produced by libpng to always have 8-bit or 16-bit components and then
+store the color as an 8-bit or 16-bit color as appropriate. The color contains
+separate gray and RGB component values, so you can let libpng produce gray or
+RGB output according to the input format, but low bit depth grayscale images
+must always be converted to at least 8-bit format. (Even though low bit depth
+grayscale images can't have an alpha channel they can have a transparent
+color!)
+
+You set the transforms you need later, either as flags to the high level
+interface or libpng API calls for the low level interface. For reference the
+settings and API calls required are:
+
+8-bit values:
+ PNG_TRANSFORM_SCALE_16 | PNG_EXPAND
+ png_set_expand(png_ptr); png_set_scale_16(png_ptr);
+
+ If you must get exactly the same inaccurate results
+ produced by default in versions prior to libpng-1.5.4,
+ use PNG_TRANSFORM_STRIP_16 and png_set_strip_16(png_ptr)
+ instead.
+
+16-bit values:
+ PNG_TRANSFORM_EXPAND_16
+ png_set_expand_16(png_ptr);
+
+In either case palette image data will be expanded to RGB. If you just want
+color data you can add PNG_TRANSFORM_GRAY_TO_RGB or png_set_gray_to_rgb(png_ptr)
+to the list.
+
+Calling png_set_background before the PNG file header is read will not work
+prior to libpng-1.5.4. Because the failure may result in unexpected warnings or
+errors it is therefore much safer to call png_set_background after the head has
+been read. Unfortunately this means that prior to libpng-1.5.4 it cannot be
+used with the high level interface.
+
The high-level read interface
At this point there are two ways to proceed; through the high-level
@@ -457,8 +910,10 @@ the entire image into memory, and (b) the input transformations you want to do are limited to the following set:
PNG_TRANSFORM_IDENTITY No transformation
- PNG_TRANSFORM_STRIP_16 Strip 16-bit samples to
- 8 bits
+ PNG_TRANSFORM_SCALE_16 Strip 16-bit samples to
+ 8-bit accurately
+ PNG_TRANSFORM_STRIP_16 Chop 16-bit samples to
+ 8-bit less accurately
PNG_TRANSFORM_STRIP_ALPHA Discard the alpha channel
PNG_TRANSFORM_PACKING Expand 1, 2 and 4-bit
samples to bytes
@@ -477,6 +932,7 @@ you want to do are limited to the following set: PNG_TRANSFORM_SWAP_ENDIAN Byte-swap 16-bit samples
PNG_TRANSFORM_GRAY_TO_RGB Expand grayscale samples
to RGB (or GA to RGBA)
+ PNG_TRANSFORM_EXPAND_16 Expand samples to 16 bits
(This excludes setting a background color, doing gamma transformation,
quantizing, and setting filler.) If this is the case, simply do this:
@@ -508,17 +964,22 @@ row_pointers prior to calling png_read_png() with if (height > PNG_UINT_32_MAX/png_sizeof(png_byte))
png_error (png_ptr,
- "Image is too tall to process in memory");
+ "Image is too tall to process in memory");
+
if (width > PNG_UINT_32_MAX/pixel_size)
png_error (png_ptr,
- "Image is too wide to process in memory");
+ "Image is too wide to process in memory");
+
row_pointers = png_malloc(png_ptr,
- height*png_sizeof(png_bytep));
+ height*png_sizeof(png_bytep));
+
for (int i=0; i<height, i++)
row_pointers[i]=NULL; /* security precaution */
+
for (int i=0; i<height, i++)
row_pointers[i]=png_malloc(png_ptr,
- width*pixel_size);
+ width*pixel_size);
+
png_set_rows(png_ptr, info_ptr, &row_pointers);
Alternatively you could allocate your image in one big block and define
@@ -528,7 +989,7 @@ If you use png_set_rows(), the application is responsible for freeing row_pointers (and row_pointers[i], if they were separately allocated).
If you don't allocate row_pointers ahead of time, png_read_png() will
-do it, and it'll be free'ed when you call png_destroy_*().
+do it, and it'll be free'ed by libpng when you call png_destroy_*().
The low-level read interface
@@ -540,6 +1001,22 @@ call to png_read_info(). This will process all chunks up to but not including the image data.
+This also copies some of the data from the PNG file into the decode structure
+for use in later transformations. Important information copied in is:
+
+1) The PNG file gamma from the gAMA chunk. This overwrites the default value
+provided by an earlier call to png_set_gamma or png_set_alpha_mode.
+
+2) Prior to libpng-1.5.4 the background color from a bKGd chunk. This
+damages the information provided by an earlier call to png_set_background
+resulting in unexpected behavior. Libpng-1.5.4 no longer does this.
+
+3) The number of significant bits in each component value. Libpng uses this to
+optimize gamma handling by reducing the internal lookup table sizes.
+
+4) The transparent color information from a tRNS chunk. This can be modified by
+a later call to png_set_tRNS.
+
Querying the info structure
Functions are used to get the information from the info_ptr once it
@@ -552,13 +1029,16 @@ in until png_read_end() has read the chunk data following the image. width - holds the width of the image
in pixels (up to 2^31).
+
height - holds the height of the image
in pixels (up to 2^31).
+
bit_depth - holds the bit depth of one of the
image channels. (valid values are
1, 2, 4, 8, 16 and depend also on
the color_type. See also
significant bits (sBIT) below).
+
color_type - describes which color/alpha channels
are present.
PNG_COLOR_TYPE_GRAY
@@ -576,15 +1056,17 @@ in until png_read_end() has read the chunk data following the image. PNG_COLOR_MASK_COLOR
PNG_COLOR_MASK_ALPHA
+ interlace_type - (PNG_INTERLACE_NONE or
+ PNG_INTERLACE_ADAM7)
+
+ compression_type - (must be PNG_COMPRESSION_TYPE_BASE
+ for PNG 1.0)
+
filter_method - (must be PNG_FILTER_TYPE_BASE
for PNG 1.0, and can also be
PNG_INTRAPIXEL_DIFFERENCING if
the PNG datastream is embedded in
a MNG-1.0 datastream)
- compression_type - (must be PNG_COMPRESSION_TYPE_BASE
- for PNG 1.0)
- interlace_type - (PNG_INTERLACE_NONE or
- PNG_INTERLACE_ADAM7)
Any or all of interlace_type, compression_type, or
filter_method can be NULL if you are
@@ -599,28 +1081,38 @@ in until png_read_end() has read the chunk data following the image. width = png_get_image_width(png_ptr,
info_ptr);
+
height = png_get_image_height(png_ptr,
info_ptr);
+
bit_depth = png_get_bit_depth(png_ptr,
info_ptr);
+
color_type = png_get_color_type(png_ptr,
info_ptr);
- filter_method = png_get_filter_type(png_ptr,
+
+ interlace_type = png_get_interlace_type(png_ptr,
info_ptr);
+
compression_type = png_get_compression_type(png_ptr,
info_ptr);
- interlace_type = png_get_interlace_type(png_ptr,
+
+ filter_method = png_get_filter_type(png_ptr,
info_ptr);
channels = png_get_channels(png_ptr, info_ptr);
+
channels - number of channels of info for the
color type (valid values are 1 (GRAY,
PALETTE), 2 (GRAY_ALPHA), 3 (RGB),
4 (RGB_ALPHA or RGB + filler byte))
+
rowbytes = png_get_rowbytes(png_ptr, info_ptr);
+
rowbytes - number of bytes needed to hold a row
signature = png_get_signature(png_ptr, info_ptr);
+
signature - holds the signature read from the
file (if any). The data is kept in
the same offset it would be if the
@@ -638,18 +1130,54 @@ data has been read, or zero if it is missing. The parameters to the png_get_<chunk> are set directly if they are simple data types, or a
pointer into the info_ptr is returned for any complex types.
+The colorspace data from gAMA, cHRM, sRGB, iCCP, and sBIT chunks
+is simply returned to give the application information about how the
+image was encoded. Libpng itself only does transformations using the file
+gamma when combining semitransparent pixels with the background color.
+
png_get_PLTE(png_ptr, info_ptr, &palette,
&num_palette);
+
palette - the palette for the file
(array of png_color)
+
num_palette - number of entries in the palette
- png_get_gAMA(png_ptr, info_ptr, &gamma);
- gamma - the gamma the file is written
- at (PNG_INFO_gAMA)
+ png_get_gAMA(png_ptr, info_ptr, &file_gamma);
+ png_get_gAMA_fixed(png_ptr, info_ptr, &int_file_gamma);
+
+ file_gamma - the gamma at which the file was
+ written (PNG_INFO_gAMA)
+
+ int_file_gamma - 100,000 times the gamma at which the
+ file is written
+
+ png_get_cHRM(png_ptr, info_ptr, &white_x, &white_y, &red_x,
+ &red_y, &green_x, &green_y, &blue_x, &blue_y)
+ png_get_cHRM_XYZ(png_ptr, info_ptr, &red_X, &red_Y, &red_Z, &green_X,
+ &green_Y, &green_Z, &blue_X, &blue_Y, &blue_Z)
+ png_get_cHRM_fixed(png_ptr, info_ptr, &int_white_x, &int_white_y,
+ &int_red_x, &int_red_y, &int_green_x, &int_green_y,
+ &int_blue_x, &int_blue_y)
+ png_get_cHRM_XYZ_fixed(png_ptr, info_ptr, &int_red_X, &int_red_Y,
+ &int_red_Z, &int_green_X, &int_green_Y, &int_green_Z,
+ &int_blue_X, &int_blue_Y, &int_blue_Z)
+
+ {white,red,green,blue}_{x,y}
+ A color space encoding specified using the
+ chromaticities of the end points and the
+ white point. (PNG_INFO_cHRM)
+
+ {red,green,blue}_{X,Y,Z}
+ A color space encoding specified using the encoding end
+ points - the CIE tristimulus specification of the intended
+ color of the red, green and blue channels in the PNG RGB
+ data. The white point is simply the sum of the three end
+ points. (PNG_INFO_cHRM)
png_get_sRGB(png_ptr, info_ptr, &srgb_intent);
- srgb_intent - the rendering intent (PNG_INFO_sRGB)
+
+ file_srgb_intent - the rendering intent (PNG_INFO_sRGB)
The presence of the sRGB chunk
means that the pixel data is in the
sRGB color space. This chunk also
@@ -658,16 +1186,21 @@ pointer into the info_ptr is returned for any complex types. png_get_iCCP(png_ptr, info_ptr, &name,
&compression_type, &profile, &proflen);
- name - The profile name.
- compression - The compression type; always
- PNG_COMPRESSION_TYPE_BASE for PNG 1.0.
- You may give NULL to this argument to
- ignore it.
- profile - International Color Consortium color
- profile data. May contain NULs.
- proflen - length of profile data in bytes.
+
+ name - The profile name.
+
+ compression_type - The compression type; always
+ PNG_COMPRESSION_TYPE_BASE for PNG 1.0.
+ You may give NULL to this argument to
+ ignore it.
+
+ profile - International Color Consortium color
+ profile data. May contain NULs.
+
+ proflen - length of profile data in bytes.
png_get_sBIT(png_ptr, info_ptr, &sig_bit);
+
sig_bit - the number of significant bits for
(PNG_INFO_sBIT) each of the gray,
red, green, and blue channels,
@@ -676,57 +1209,80 @@ pointer into the info_ptr is returned for any complex types. png_get_tRNS(png_ptr, info_ptr, &trans_alpha,
&num_trans, &trans_color);
+
trans_alpha - array of alpha (transparency)
entries for palette (PNG_INFO_tRNS)
+
+ num_trans - number of transparent entries
+ (PNG_INFO_tRNS)
+
trans_color - graylevel or color sample values of
the single transparent color for
non-paletted images (PNG_INFO_tRNS)
- num_trans - number of transparent entries
- (PNG_INFO_tRNS)
png_get_hIST(png_ptr, info_ptr, &hist);
(PNG_INFO_hIST)
+
hist - histogram of palette (array of
png_uint_16)
png_get_tIME(png_ptr, info_ptr, &mod_time);
+
mod_time - time image was last modified
(PNG_VALID_tIME)
png_get_bKGD(png_ptr, info_ptr, &background);
- background - background color (PNG_VALID_bKGD)
+
+ background - background color (of type
+ png_color_16p) (PNG_VALID_bKGD)
valid 16-bit red, green and blue
values, regardless of color_type
num_comments = png_get_text(png_ptr, info_ptr,
&text_ptr, &num_text);
+
num_comments - number of comments
+
text_ptr - array of png_text holding image
comments
+
text_ptr[i].compression - type of compression used
on "text" PNG_TEXT_COMPRESSION_NONE
PNG_TEXT_COMPRESSION_zTXt
PNG_ITXT_COMPRESSION_NONE
PNG_ITXT_COMPRESSION_zTXt
+
text_ptr[i].key - keyword for comment. Must contain
1-79 characters.
+
text_ptr[i].text - text comments for current
keyword. Can be empty.
+
text_ptr[i].text_length - length of text string,
after decompression, 0 for iTXt
+
text_ptr[i].itxt_length - length of itxt string,
after decompression, 0 for tEXt/zTXt
+
text_ptr[i].lang - language of comment (empty
string for unknown).
+
text_ptr[i].lang_key - keyword in UTF-8
(empty string for unknown).
+
Note that the itxt_length, lang, and lang_key
- members of the text_ptr structure only exist
- when the library is built with iTXt chunk support.
+ members of the text_ptr structure only exist when the
+ library is built with iTXt chunk support. Prior to
+ libpng-1.4.0 the library was built by default without
+ iTXt support. Also note that when iTXt is supported,
+ they contain NULL pointers when the "compression"
+ field contains PNG_TEXT_COMPRESSION_NONE or
+ PNG_TEXT_COMPRESSION_zTXt.
num_text - number of comments (same as
num_comments; you can put NULL here
to avoid the duplication)
+
Note while png_set_text() will accept text, language,
and translated keywords that can be NULL pointers, the
structure returned by png_get_text will always contain
@@ -735,90 +1291,137 @@ pointer into the info_ptr is returned for any complex types. num_spalettes = png_get_sPLT(png_ptr, info_ptr,
&palette_ptr);
+
+ num_spalettes - number of sPLT chunks read.
+
palette_ptr - array of palette structures holding
contents of one or more sPLT chunks
read.
- num_spalettes - number of sPLT chunks read.
png_get_oFFs(png_ptr, info_ptr, &offset_x, &offset_y,
&unit_type);
+
offset_x - positive offset from the left edge
- of the screen
+ of the screen (can be negative)
+
offset_y - positive offset from the top edge
- of the screen
+ of the screen (can be negative)
+
unit_type - PNG_OFFSET_PIXEL, PNG_OFFSET_MICROMETER
png_get_pHYs(png_ptr, info_ptr, &res_x, &res_y,
&unit_type);
+
res_x - pixels/unit physical resolution in
x direction
+
res_y - pixels/unit physical resolution in
x direction
+
unit_type - PNG_RESOLUTION_UNKNOWN,
PNG_RESOLUTION_METER
png_get_sCAL(png_ptr, info_ptr, &unit, &width,
&height)
+
unit - physical scale units (an integer)
+
width - width of a pixel in physical scale units
+
height - height of a pixel in physical scale units
(width and height are doubles)
png_get_sCAL_s(png_ptr, info_ptr, &unit, &width,
&height)
+
unit - physical scale units (an integer)
+
width - width of a pixel in physical scale units
+ (expressed as a string)
+
height - height of a pixel in physical scale units
(width and height are strings like "2.54")
num_unknown_chunks = png_get_unknown_chunks(png_ptr,
info_ptr, &unknowns)
+
unknowns - array of png_unknown_chunk
structures holding unknown chunks
+
unknowns[i].name - name of unknown chunk
+
unknowns[i].data - data of unknown chunk
+
unknowns[i].size - size of unknown chunk's data
+
unknowns[i].location - position of chunk in file
The value of "i" corresponds to the order in which the
chunks were read from the PNG file or inserted with the
png_set_unknown_chunks() function.
+ The value of "location" is a bitwise "or" of
+
+ PNG_HAVE_IHDR (0x01)
+ PNG_HAVE_PLTE (0x02)
+ PNG_AFTER_IDAT (0x08)
+
The data from the pHYs chunk can be retrieved in several convenient
forms:
res_x = png_get_x_pixels_per_meter(png_ptr,
info_ptr)
+
res_y = png_get_y_pixels_per_meter(png_ptr,
info_ptr)
+
res_x_and_y = png_get_pixels_per_meter(png_ptr,
info_ptr)
+
res_x = png_get_x_pixels_per_inch(png_ptr,
info_ptr)
+
res_y = png_get_y_pixels_per_inch(png_ptr,
info_ptr)
+
res_x_and_y = png_get_pixels_per_inch(png_ptr,
info_ptr)
+
aspect_ratio = png_get_pixel_aspect_ratio(png_ptr,
info_ptr)
- (Each of these returns 0 [signifying "unknown"] if
+ Each of these returns 0 [signifying "unknown"] if
the data is not present or if res_x is 0;
- res_x_and_y is 0 if res_x != res_y)
+ res_x_and_y is 0 if res_x != res_y
+
+ Note that because of the way the resolutions are
+ stored internally, the inch conversions won't
+ come out to exactly even number. For example,
+ 72 dpi is stored as 0.28346 pixels/meter, and
+ when this is retrieved it is 71.9988 dpi, so
+ be sure to round the returned value appropriately
+ if you want to display a reasonable-looking result.
The data from the oFFs chunk can be retrieved in several convenient
forms:
x_offset = png_get_x_offset_microns(png_ptr, info_ptr);
+
y_offset = png_get_y_offset_microns(png_ptr, info_ptr);
+
x_offset = png_get_x_offset_inches(png_ptr, info_ptr);
+
y_offset = png_get_y_offset_inches(png_ptr, info_ptr);
- (Each of these returns 0 [signifying "unknown" if both
+ Each of these returns 0 [signifying "unknown" if both
x and y are 0] if the data is not present or if the
- chunk is present but the unit is the pixel)
+ chunk is present but the unit is the pixel. The
+ remark about inexact inch conversions applies here
+ as well, because a value in inches can't always be
+ converted to microns and back without some loss
+ of precision.
-For more information, see the png_info definition in png.h and the
+For more information, see the
PNG specification for chunk contents. Be careful with trusting
rowbytes, as some of the transformations could increase the space
needed to hold a row (expand, filler, gray_to_rgb, etc.).
@@ -853,17 +1456,20 @@ to handle any special transformations of the image data. The various ways to transform the data will be described in the order that they
should occur. This is important, as some of these change the color
type and/or bit depth of the data, and some others only work on
-certain color types and bit depths. Even though each transformation
-checks to see if it has data that it can do something with, you should
-make sure to only enable a transformation if it will be valid for the
-data. For example, don't swap red and blue on grayscale data.
+certain color types and bit depths.
+
+Transformations you request are ignored if they don't have any meaning for a
+particular input data format. However some transformations can have an effect
+as a result of a previous transformation. If you specify a contradictory set of
+transformations, for example both adding and removing the alpha channel, you
+cannot predict the final result.
-The colors used for the background and transparency values should be
-supplied in the same format/depth as the current image data. They
-are stored in the same format/depth as the image data in a bKGD or tRNS
-chunk, so this is what libpng expects for this data. The colors are
-transformed to keep in sync with the image data when an application
-calls the png_read_update_info() routine (see below).
+The color used for the transparency values should be supplied in the same
+format/depth as the current image data. It is stored in the same format/depth
+as the image data in a tRNS chunk, so this is what libpng expects for this data.
+
+The color used for the background value depends on the need_expand argument as
+described below.
Data will be decoded into the supplied row buffers packed into bytes
unless the library has been told to transform it into another format.
@@ -873,12 +1479,12 @@ byte, unless png_set_packing() is called. 8-bit RGB data will be stored in RGB RGB RGB format unless png_set_filler() or png_set_add_alpha()
is called to insert filler bytes, either before or after each RGB triplet.
16-bit RGB data will be returned RRGGBB RRGGBB, with the most significant
-byte of the color value first, unless png_set_strip_16() is called to
+byte of the color value first, unless png_set_scale_16() is called to
transform it to regular RGB RGB triplets, or png_set_filler() or
png_set_add alpha() is called to insert filler bytes, either before or
after each RRGGBB triplet. Similarly, 8-bit or 16-bit grayscale data can
-be modified with
-png_set_filler(), png_set_add_alpha(), or png_set_strip_16().
+be modified with png_set_filler(), png_set_add_alpha(), png_set_strip_16(),
+or png_set_scale_16().
The following code transforms grayscale images of less than 8 to 8 bits,
changes paletted images to RGB, and adds a full alpha channel if there is
@@ -889,13 +1495,13 @@ viewing application that wishes to treat all images in the same way. if (color_type == PNG_COLOR_TYPE_PALETTE)
png_set_palette_to_rgb(png_ptr);
- if (color_type == PNG_COLOR_TYPE_GRAY &&
- bit_depth < 8) png_set_expand_gray_1_2_4_to_8(png_ptr);
-
if (png_get_valid(png_ptr, info_ptr,
PNG_INFO_tRNS)) png_set_tRNS_to_alpha(png_ptr);
-These three functions are actually aliases for png_set_expand(), added
+ if (color_type == PNG_COLOR_TYPE_GRAY &&
+ bit_depth < 8) png_set_expand_gray_1_2_4_to_8(png_ptr);
+
+The first two functions are actually aliases for png_set_expand(), added
in libpng version 1.0.4, with the function names expanded to improve code
readability. In some future version they may actually do different
things.
@@ -903,56 +1509,93 @@ things. As of libpng version 1.2.9, png_set_expand_gray_1_2_4_to_8() was
added. It expands the sample depth without changing tRNS to alpha.
-As of libpng version 1.4.3, not all possible expansions are supported.
+As of libpng version 1.5.2, png_set_expand_16() was added. It behaves as
+png_set_expand(); however, the resultant channels have 16 bits rather than 8.
+Use this when the output color or gray channels are made linear to avoid fairly
+severe accuracy loss.
+
+ if (bit_depth < 16)
+ png_set_expand_16(png_ptr);
+
+PNG can have files with 16 bits per channel. If you only can handle
+8 bits per channel, this will strip the pixels down to 8-bit.
+
+ if (bit_depth == 16)
+#if PNG_LIBPNG_VER >= 10504
+ png_set_scale_16(png_ptr);
+#else
+ png_set_strip_16(png_ptr);
+#endif
+
+(The more accurate "png_set_scale_16()" API became available in libpng version
+1.5.4).
+
+If you need to process the alpha channel on the image separately from the image
+data (for example if you convert it to a bitmap mask) it is possible to have
+libpng strip the channel leaving just RGB or gray data:
+
+ if (color_type & PNG_COLOR_MASK_ALPHA)
+ png_set_strip_alpha(png_ptr);
+
+If you strip the alpha channel you need to find some other way of dealing with
+the information. If, instead, you want to convert the image to an opaque
+version with no alpha channel use png_set_background; see below.
+
+As of libpng version 1.5.2, almost all useful expansions are supported, the
+major ommissions are conversion of grayscale to indexed images (which can be
+done trivially in the application) and conversion of indexed to grayscale (which
+can be done by a trivial manipulation of the palette.)
In the following table, the 01 means grayscale with depth<8, 31 means
indexed with depth<8, other numerals represent the color type, "T" means
the tRNS chunk is present, A means an alpha channel is present, and O
means tRNS or alpha is present but all pixels in the image are opaque.
- FROM 01 31 0 0T 0O 2 2T 2O 3 3T 3O 4A 4O 6A 6O
+ FROM 01 31 0 0T 0O 2 2T 2O 3 3T 3O 4A 4O 6A 6O
TO
- 01 -
- 31 -
- 0 1 -
- 0T -
- 0O -
- 2 GX -
- 2T -
- 2O -
- 3 1 -
- 3T -
- 3O -
- 4A T -
- 4O -
- 6A GX TX TX -
- 6O GX TX -
+ 01 - [G] - - - - - - - - - - - - -
+ 31 [Q] Q [Q] [Q] [Q] Q Q Q Q Q Q [Q] [Q] Q Q
+ 0 1 G + . . G G G G G G B B GB GB
+ 0T lt Gt t + . Gt G G Gt G G Bt Bt GBt GBt
+ 0O lt Gt t . + Gt Gt G Gt Gt G Bt Bt GBt GBt
+ 2 C P C C C + . . C - - CB CB B B
+ 2T Ct - Ct C C t + t - - - CBt CBt Bt Bt
+ 2O Ct - Ct C C t t + - - - CBt CBt Bt Bt
+ 3 [Q] p [Q] [Q] [Q] Q Q Q + . . [Q] [Q] Q Q
+ 3T [Qt] p [Qt][Q] [Q] Qt Qt Qt t + t [Qt][Qt] Qt Qt
+ 3O [Qt] p [Qt][Q] [Q] Qt Qt Qt t t + [Qt][Qt] Qt Qt
+ 4A lA G A T T GA GT GT GA GT GT + BA G GBA
+ 4O lA GBA A T T GA GT GT GA GT GT BA + GBA G
+ 6A CA PA CA C C A T tT PA P P C CBA + BA
+ 6O CA PBA CA C C A tT T PA P P CBA C BA +
Within the matrix,
+ "+" identifies entries where 'from' and 'to' are the same.
"-" means the transformation is not supported.
+ "." means nothing is necessary (a tRNS chunk can just be ignored).
+ "t" means the transformation is obtained by png_set_tRNS.
+ "A" means the transformation is obtained by png_set_add_alpha().
"X" means the transformation is obtained by png_set_expand().
"1" means the transformation is obtained by
- png_set_expand_gray_1_2_4_to_8
- "G" means the transformation is obtained by
- png_set_gray_to_rgb().
+ png_set_expand_gray_1_2_4_to_8() (and by png_set_expand()
+ if there is no transparency in the original or the final
+ format).
+ "C" means the transformation is obtained by png_set_gray_to_rgb().
+ "G" means the transformation is obtained by png_set_rgb_to_gray().
"P" means the transformation is obtained by
png_set_expand_palette_to_rgb().
+ "p" means the transformation is obtained by png_set_packing().
+ "Q" means the transformation is obtained by png_set_quantize().
"T" means the transformation is obtained by
png_set_tRNS_to_alpha().
+ "B" means the transformation is obtained by
+ png_set_background(), or png_strip_alpha().
-PNG can have files with 16 bits per channel. If you only can handle
-8 bits per channel, this will strip the pixels down to 8 bit.
-
- if (bit_depth == 16)
- png_set_strip_16(png_ptr);
-
-If, for some reason, you don't need the alpha channel on an image,
-and you want to remove it rather than combining it with the background
-(but the image author certainly had in mind that you *would* combine
-it with the background, so that's what you should probably do):
-
- if (color_type & PNG_COLOR_MASK_ALPHA)
- png_set_strip_alpha(png_ptr);
+When an entry has multiple transforms listed all are required to cause the
+right overall transformation. When two transforms are separated by a comma
+either will do the job. When transforms are enclosed in [] the transform should
+do the job but this is currently unimplemented - a different format will result
+if the suggested transformations are used.
In PNG files, the alpha channel in an image
is the level of opacity. If you need the alpha channel in an image to
@@ -969,7 +1612,7 @@ files. This code expands to 1 pixel per byte without changing the values of the pixels:
if (bit_depth < 8)
- png_set_packing(png_ptr);
+ png_set_packing(png_ptr);
PNG files have possible bit depths of 1, 2, 4, 8, and 16. All pixels
stored in a PNG image have been "scaled" or "shifted" up to the next
@@ -981,20 +1624,20 @@ image. This call reduces the pixels back down to the original bit depth: png_color_8p sig_bit;
if (png_get_sBIT(png_ptr, info_ptr, &sig_bit))
- png_set_shift(png_ptr, sig_bit);
+ png_set_shift(png_ptr, sig_bit);
PNG files store 3-color pixels in red, green, blue order. This code
changes the storage of the pixels to blue, green, red:
if (color_type == PNG_COLOR_TYPE_RGB ||
color_type == PNG_COLOR_TYPE_RGB_ALPHA)
- png_set_bgr(png_ptr);
+ png_set_bgr(png_ptr);
PNG files store RGB pixels packed into 3 or 6 bytes. This code expands them
into 4 or 8 bytes for windowing systems that need them in this format:
if (color_type == PNG_COLOR_TYPE_RGB)
- png_set_filler(png_ptr, filler, PNG_FILLER_BEFORE);
+ png_set_filler(png_ptr, filler, PNG_FILLER_BEFORE);
where "filler" is the 8 or 16-bit number to fill with, and the location is
either PNG_FILLER_BEFORE or PNG_FILLER_AFTER, depending upon whether
@@ -1007,8 +1650,8 @@ Note that png_set_filler() does not change the color type. If you want to do that, you can add a true alpha channel with
if (color_type == PNG_COLOR_TYPE_RGB ||
- color_type == PNG_COLOR_TYPE_GRAY)
- png_set_add_alpha(png_ptr, filler, PNG_FILLER_AFTER);
+ color_type == PNG_COLOR_TYPE_GRAY)
+ png_set_add_alpha(png_ptr, filler, PNG_FILLER_AFTER);
where "filler" contains the alpha value to assign to each pixel.
This function was added in libpng-1.2.7.
@@ -1017,175 +1660,158 @@ If you are reading an image with an alpha channel, and you need the data as ARGB instead of the normal PNG format RGBA:
if (color_type == PNG_COLOR_TYPE_RGB_ALPHA)
- png_set_swap_alpha(png_ptr);
+ png_set_swap_alpha(png_ptr);
For some uses, you may want a grayscale image to be represented as
RGB. This code will do that conversion:
if (color_type == PNG_COLOR_TYPE_GRAY ||
color_type == PNG_COLOR_TYPE_GRAY_ALPHA)
- png_set_gray_to_rgb(png_ptr);
+ png_set_gray_to_rgb(png_ptr);
Conversely, you can convert an RGB or RGBA image to grayscale or grayscale
with alpha.
if (color_type == PNG_COLOR_TYPE_RGB ||
color_type == PNG_COLOR_TYPE_RGB_ALPHA)
- png_set_rgb_to_gray_fixed(png_ptr, error_action,
- int red_weight, int green_weight);
+ png_set_rgb_to_gray(png_ptr, error_action,
+ double red_weight, double green_weight);
error_action = 1: silently do the conversion
+
error_action = 2: issue a warning if the original
image has any pixel where
red != green or red != blue
+
error_action = 3: issue an error and abort the
conversion if the original
image has any pixel where
red != green or red != blue
- red_weight: weight of red component times 100000
- green_weight: weight of green component times 100000
+ red_weight: weight of red component
+
+ green_weight: weight of green component
If either weight is negative, default
- weights (21268, 71514) are used.
+ weights are used.
+
+In the corresponding fixed point API the red_weight and green_weight values are
+simply scaled by 100,000:
+
+ png_set_rgb_to_gray(png_ptr, error_action,
+ png_fixed_point red_weight,
+ png_fixed_point green_weight);
If you have set error_action = 1 or 2, you can
later check whether the image really was gray, after processing
the image rows, with the png_get_rgb_to_gray_status(png_ptr) function.
It will return a png_byte that is zero if the image was gray or
-1 if there were any non-gray pixels. bKGD and sBIT data
+1 if there were any non-gray pixels. Background and sBIT data
will be silently converted to grayscale, using the green channel
-data, regardless of the error_action setting.
+data for sBIT, regardless of the error_action setting.
-With red_weight+green_weight<=100000,
-the normalized graylevel is computed:
+The default values come from the PNG file cHRM chunk if present; otherwise, the
+defaults correspond to the ITU-R recommendation 709, and also the sRGB color
+space, as recommended in the Charles Poynton's Colour FAQ,
+<http://www.poynton.com/>, in section 9:
- int rw = red_weight * 65536;
- int gw = green_weight * 65536;
- int bw = 65536 - (rw + gw);
- gray = (rw*red + gw*green + bw*blue)/65536;
+ <http://www.poynton.com/notes/colour_and_gamma/ColorFAQ.html#RTFToC9>
-The default values approximate those recommended in the Charles
-Poynton's Color FAQ, <http://www.inforamp.net/~poynton/>
-Copyright (c) 1998-01-04 Charles Poynton <poynton at inforamp.net>
-
- Y = 0.212671 * R + 0.715160 * G + 0.072169 * B
+ Y = 0.2126 * R + 0.7152 * G + 0.0722 * B
-Libpng approximates this with
+Previous versions of this document, 1998 through 2002, recommended a slightly
+different formula:
- Y = 0.21268 * R + 0.7151 * G + 0.07217 * B
+ Y = 0.212671 * R + 0.715160 * G + 0.072169 * B
-which can be expressed with integers as
+Libpng uses an integer approximation:
- Y = (6969 * R + 23434 * G + 2365 * B)/32768
+ Y = (6968 * R + 23434 * G + 2366 * B)/32768
The calculation is done in a linear colorspace, if the image gamma
-is known.
+can be determined.
-If you have a grayscale and you are using png_set_expand_depth(),
-png_set_expand(), or png_set_gray_to_rgb to change to truecolor or to
-a higher bit-depth, you must either supply the background color as a gray
-value at the original file bit-depth (need_expand = 1) or else supply the
-background color as an RGB triplet at the final, expanded bit depth
-(need_expand = 0). Similarly, if you are reading a paletted image, you
-must either supply the background color as a palette index (need_expand = 1)
-or as an RGB triplet that may or may not be in the palette (need_expand = 0).
+The png_set_background() function has been described already; it tells libpng to
+composite images with alpha or simple transparency against the supplied
+background color. For compatibility with versions of libpng earlier than
+libpng-1.5.4 it is recommended that you call the function after reading the file
+header, even if you don't want to use the color in a bKGD chunk, if one exists.
+
+If the PNG file contains a bKGD chunk (PNG_INFO_bKGD valid),
+you may use this color, or supply another color more suitable for
+the current display (e.g., the background color from a web page). You
+need to tell libpng how the color is represented, both the format of the
+component values in the color (the number of bits) and the gamma encoding of the
+color. The function takes two arguments, background_gamma_mode and need_expand
+to convey this information; however, only two combinations are likely to be
+useful:
png_color_16 my_background;
png_color_16p image_background;
if (png_get_bKGD(png_ptr, info_ptr, &image_background))
- png_set_background(png_ptr, image_background,
- PNG_BACKGROUND_GAMMA_FILE, 1, 1.0);
+ png_set_background(png_ptr, image_background,
+ PNG_BACKGROUND_GAMMA_FILE, 1/*needs to be expanded*/, 1);
else
- png_set_background(png_ptr, &my_background,
- PNG_BACKGROUND_GAMMA_SCREEN, 0, 1.0);
-
-The png_set_background() function tells libpng to composite images
-with alpha or simple transparency against the supplied background
-color. If the PNG file contains a bKGD chunk (PNG_INFO_bKGD valid),
-you may use this color, or supply another color more suitable for
-the current display (e.g., the background color from a web page). You
-need to tell libpng whether the color is in the gamma space of the
-display (PNG_BACKGROUND_GAMMA_SCREEN for colors you supply), the file
-(PNG_BACKGROUND_GAMMA_FILE for colors from the bKGD chunk), or one
-that is neither of these gammas (PNG_BACKGROUND_GAMMA_UNIQUE - I don't
-know why anyone would use this, but it's here).
-
-To properly display PNG images on any kind of system, the application needs
-to know what the display gamma is. Ideally, the user will know this, and
-the application will allow them to set it. One method of allowing the user
-to set the display gamma separately for each system is to check for a
-SCREEN_GAMMA or DISPLAY_GAMMA environment variable, which will hopefully be
-correctly set.
-
-Note that display_gamma is the overall gamma correction required to produce
-pleasing results, which depends on the lighting conditions in the surrounding
-environment. In a dim or brightly lit room, no compensation other than
-the physical gamma exponent of the monitor is needed, while in a dark room
-a slightly smaller exponent is better.
-
- double gamma, screen_gamma;
-
- if (/* We have a user-defined screen
- gamma value */)
- {
- screen_gamma = user_defined_screen_gamma;
- }
- /* One way that applications can share the same
- screen gamma value */
- else if ((gamma_str = getenv("SCREEN_GAMMA"))
- != NULL)
- {
- screen_gamma = (double)atof(gamma_str);
- }
- /* If we don't have another value */
- else
- {
- screen_gamma = 2.2; /* A good guess for a
- PC monitor in a bright office or a dim room */
- screen_gamma = 2.0; /* A good guess for a
- PC monitor in a dark room */
- screen_gamma = 1.7 or 1.0; /* A good
- guess for Mac systems */
- }
+ png_set_background(png_ptr, &my_background,
+ PNG_BACKGROUND_GAMMA_SCREEN, 0/*do not expand*/, 1);
+
+The second call was described above - my_background is in the format of the
+final, display, output produced by libpng. Because you now know the format of
+the PNG it is possible to avoid the need to choose either 8-bit or 16-bit
+output and to retain palette images (the palette colors will be modified
+appropriately and the tRNS chunk removed.) However, if you are doing this,
+take great care not to ask for transformations without checking first that
+they apply!
+
+In the first call the background color has the original bit depth and color type
+of the PNG file. So, for palette images the color is supplied as a palette
+index and for low bit greyscale images the color is a reduced bit value in
+image_background->gray.
+
+If you didn't call png_set_gamma() before reading the file header, for example
+if you need your code to remain compatible with older versions of libpng prior
+to libpng-1.5.4, this is the place to call it.
+
+Do not call it if you called png_set_alpha_mode(); doing so will damage the
+settings put in place by png_set_alpha_mode(). (If png_set_alpha_mode() is
+supported then you can certainly do png_set_gamma() before reading the PNG
+header.)
+
+This API unconditionally sets the screen and file gamma values, so it will
+override the value in the PNG file unless it is called before the PNG file
+reading starts. For this reason you must always call it with the PNG file
+value when you call it in this position:
+
+ if (png_get_gAMA(png_ptr, info_ptr, &file_gamma))
+ png_set_gamma(png_ptr, screen_gamma, file_gamma);
-The png_set_gamma() function handles gamma transformations of the data.
-Pass both the file gamma and the current screen_gamma. If the file does
-not have a gamma value, you can pass one anyway if you have an idea what
-it is (usually 0.45455 is a good guess for GIF images on PCs). Note
-that file gammas are inverted from screen gammas. See the discussions
-on gamma in the PNG specification for an excellent description of what
-gamma is, and why all applications should support it. It is strongly
-recommended that PNG viewers support gamma correction.
-
- if (png_get_gAMA(png_ptr, info_ptr, &gamma))
- png_set_gamma(png_ptr, screen_gamma, gamma);
else
png_set_gamma(png_ptr, screen_gamma, 0.45455);
If you need to reduce an RGB file to a paletted file, or if a paletted
file has more entries then will fit on your screen, png_set_quantize()
-will do that. Note that this is a simple match dither that merely
+will do that. Note that this is a simple match quantization that merely
finds the closest color available. This should work fairly well with
-optimized palettes, and fairly badly with linear color cubes. If you
-pass a palette that is larger then maximum_colors, the file will
+optimized palettes, but fairly badly with linear color cubes. If you
+pass a palette that is larger than maximum_colors, the file will
reduce the number of colors in the palette so it will fit into
-maximum_colors. If there is a histogram, it will use it to make
+maximum_colors. If there is a histogram, libpng will use it to make
more intelligent choices when reducing the palette. If there is no
histogram, it may not do as good a job.
if (color_type & PNG_COLOR_MASK_COLOR)
{
if (png_get_valid(png_ptr, info_ptr,
- PNG_INFO_PLTE))
+ PNG_INFO_PLTE))
{
png_uint_16p histogram = NULL;
png_get_hIST(png_ptr, info_ptr,
- &histogram);
+ &histogram);
png_set_quantize(png_ptr, palette, num_palette,
max_screen_colors, histogram, 1);
}
+
else
{
png_color std_color_cube[MAX_SCREEN_COLORS] =
@@ -1207,16 +1833,16 @@ zero): This function can also be used to invert grayscale and gray-alpha images:
if (color_type == PNG_COLOR_TYPE_GRAY ||
- color_type == PNG_COLOR_TYPE_GRAY_ALPHA)
+ color_type == PNG_COLOR_TYPE_GRAY_ALPHA)
png_set_invert_mono(png_ptr);
-PNG files store 16 bit pixels in network byte order (big-endian,
+PNG files store 16-bit pixels in network byte order (big-endian,
ie. most significant bits first). This code changes the storage to the
other way (little-endian, i.e. least significant bits first, the
way PCs store them):
if (bit_depth == 16)
- png_set_swap(png_ptr);
+ png_set_swap(png_ptr);
If you are using packed-pixel images (1, 2, or 4 bits/pixel), and you
need to change the order the pixels are packed into bytes, you can use:
@@ -1229,15 +1855,36 @@ the existing ones meets your needs. This is done by setting a callback with
png_set_read_user_transform_fn(png_ptr,
- read_transform_fn);
+ read_transform_fn);
You must supply the function
- void read_transform_fn(png_ptr ptr, row_info_ptr
- row_info, png_bytep data)
+ void read_transform_fn(png_structp png_ptr, png_row_infop
+ row_info, png_bytep data)
See pngtest.c for a working example. Your function will be called
-after all of the other transformations have been processed.
+after all of the other transformations have been processed. Take care with
+interlaced images if you do the interlace yourself - the width of the row is the
+width in 'row_info', not the overall image width.
+
+If supported, libpng provides two information routines that you can use to find
+where you are in processing the image:
+
+ png_get_current_pass_number(png_structp png_ptr);
+ png_get_current_row_number(png_structp png_ptr);
+
+Don't try using these outside a transform callback - firstly they are only
+supported if user transforms are supported, secondly they may well return
+unexpected results unless the row is actually being processed at the moment they
+are called.
+
+With interlaced
+images the value returned is the row in the input sub-image image. Use
+PNG_ROW_FROM_PASS_ROW(row, pass) and PNG_COL_FROM_PASS_COL(col, pass) to
+find the output pixel (x,y) given an interlaced sub-image pixel (row,col,pass).
+
+The discussion of interlace handling above contains more information on how to
+use these values.
You can also set up a pointer to a user structure for use by your
callback function, and you can inform libpng that your transform
@@ -1245,7 +1892,7 @@ function will change the number of channels or bit depth with the function
png_set_user_transform_info(png_ptr, user_ptr,
- user_depth, user_channels);
+ user_depth, user_channels);
The user's application, not libpng, is responsible for allocating and
freeing any memory required for the user structure.
@@ -1254,7 +1901,7 @@ You can retrieve the pointer via the function png_get_user_transform_ptr(). For example:
voidp read_user_transform_ptr =
- png_get_user_transform_ptr(png_ptr);
+ png_get_user_transform_ptr(png_ptr);
The last thing to handle is interlacing; this is covered in detail below,
but you must call the function here if you want libpng to handle expansion
@@ -1264,13 +1911,16 @@ of the interlaced image. After setting the transformations, libpng can update your png_info
structure to reflect any transformations you've requested with this
-call. This is most useful to update the info structure's rowbytes
-field so you can use it to allocate your image memory. This function
-will also update your palette with the correct screen_gamma and
-background if these have been given with the calls above.
+call.
png_read_update_info(png_ptr, info_ptr);
+This is most useful to update the info structure's rowbytes
+field so you can use it to allocate your image memory. This function
+will also update your palette with the correct screen_gamma and
+background if these have been given with the calls above. You may
+only call png_read_update_info() once with a particular info_ptr.
+
After you call png_read_update_info(), you can allocate any
memory you need to hold the image. The row data is simply
raw byte data for all forms of images. As the actual allocation
@@ -1279,6 +1929,15 @@ are allocating one large chunk, you will need to build an array of pointers to each row, as it will be needed for some
of the functions below.
+Remember: Before you call png_read_update_info(), the png_get_*()
+functions return the values corresponding to the original PNG image.
+After you call png_read_update_info the values refer to the image
+that libpng will output. Consequently you must call all the png_set_
+functions before you call png_read_update_info(). This is particularly
+important for png_set_interlace_handling() - if you are going to call
+png_read_update_info() you must call png_set_interlace_handling() before
+it unless you want to receive interlaced output.
+
Reading image data
After you've allocated memory, you can read the image data.
@@ -1288,9 +1947,10 @@ call png_read_image() and libpng will read in all the image data and put it in the memory area supplied. You will need to pass in
an array of pointers to each row.
-This function automatically handles interlacing, so you don't need
-to call png_set_interlace_handling() or call this function multiple
-times, or any of that other stuff necessary with png_read_rows().
+This function automatically handles interlacing, so you don't
+need to call png_set_interlace_handling() (unless you call
+png_read_update_info()) or call this function multiple times, or any
+of that other stuff necessary with png_read_rows().
png_read_image(png_ptr, row_pointers);
@@ -1305,7 +1965,7 @@ use png_read_rows() instead. If there is no interlacing (check interlace_type == PNG_INTERLACE_NONE), this is simple:
png_read_rows(png_ptr, row_pointers, NULL,
- number_of_rows);
+ number_of_rows);
where row_pointers is the same as in the png_read_image() call.
@@ -1317,13 +1977,15 @@ a single row_pointer instead of an array of row_pointers: If the file is interlaced (interlace_type != 0 in the IHDR chunk), things
get somewhat harder. The only current (PNG Specification version 1.2)
-interlacing type for PNG is (interlace_type == PNG_INTERLACE_ADAM7)
-is a somewhat complicated 2D interlace scheme, known as Adam7, that
+interlacing type for PNG is (interlace_type == PNG_INTERLACE_ADAM7);
+a somewhat complicated 2D interlace scheme, known as Adam7, that
breaks down an image into seven smaller images of varying size, based
-on an 8x8 grid.
+on an 8x8 grid. This number is defined (from libpng 1.5) as
+PNG_INTERLACE_ADAM7_PASSES in png.h
libpng can fill out those images or it can give them to you "as is".
-If you want them filled out, there are two ways to do that. The one
+It is almost always better to have libpng handle the interlacing for you.
+If you want the images filled out, there are two ways to do that. The one
mentioned in the PNG specification is to expand each pixel to cover
those pixels that have not been read yet (the "rectangle" method).
This results in a blocky image for the first pass, which gradually
@@ -1333,37 +1995,20 @@ rest of the image remaining whatever colors they were initialized to before the start of the read. The first method usually looks better,
but tends to be slower, as there are more pixels to put in the rows.
-If you don't want libpng to handle the interlacing details, just call
-png_read_rows() seven times to read in all seven images. Each of the
-images is a valid image by itself, or they can all be combined on an
-8x8 grid to form a single image (although if you intend to combine them
-you would be far better off using the libpng interlace handling).
-
-The first pass will return an image 1/8 as wide as the entire image
-(every 8th column starting in column 0) and 1/8 as high as the original
-(every 8th row starting in row 0), the second will be 1/8 as wide
-(starting in column 4) and 1/8 as high (also starting in row 0). The
-third pass will be 1/4 as wide (every 4th pixel starting in column 0) and
-1/8 as high (every 8th row starting in row 4), and the fourth pass will
-be 1/4 as wide and 1/4 as high (every 4th column starting in column 2,
-and every 4th row starting in row 0). The fifth pass will return an
-image 1/2 as wide, and 1/4 as high (starting at column 0 and row 2),
-while the sixth pass will be 1/2 as wide and 1/2 as high as the original
-(starting in column 1 and row 0). The seventh and final pass will be as
-wide as the original, and 1/2 as high, containing all of the odd
-numbered scanlines. Phew!
-
-If you want libpng to expand the images, call this before calling
-png_start_read_image() or png_read_update_info():
+If, as is likely, you want libpng to expand the images, call this before
+calling png_start_read_image() or png_read_update_info():
if (interlace_type == PNG_INTERLACE_ADAM7)
- number_of_passes
+ number_of_passes
= png_set_interlace_handling(png_ptr);
-This will return the number of passes needed. Currently, this
-is seven, but may change if another interlace type is added.
-This function can be called even if the file is not interlaced,
-where it will return one pass.
+This will return the number of passes needed. Currently, this is seven,
+but may change if another interlace type is added. This function can be
+called even if the file is not interlaced, where it will return one pass.
+You then need to read the whole image 'number_of_passes' times. Each time
+will distribute the pixels from the current pass to the correct place in
+the output image, so you need to supply the same rows to png_read_rows in
+each pass.
If you are not going to display the image after each pass, but are
going to wait until the entire image is read in, use the sparkle
@@ -1380,14 +2025,104 @@ not the data. Each pass only writes the pixels appropriate for that pass, and assumes the data from previous passes is still valid.
png_read_rows(png_ptr, row_pointers, NULL,
- number_of_rows);
+ number_of_rows);
If you only want the first effect (the rectangles), do the same as
before except pass the row buffer in the third parameter, and leave
the second parameter NULL.
png_read_rows(png_ptr, NULL, row_pointers,
- number_of_rows);
+ number_of_rows);
+
+If you don't want libpng to handle the interlacing details, just call
+png_read_rows() PNG_INTERLACE_ADAM7_PASSES times to read in all the images.
+Each of the images is a valid image by itself; however, you will almost
+certainly need to distribute the pixels from each sub-image to the
+correct place. This is where everything gets very tricky.
+
+If you want to retrieve the separate images you must pass the correct
+number of rows to each successive call of png_read_rows(). The calculation
+gets pretty complicated for small images, where some sub-images may
+not even exist because either their width or height ends up zero.
+libpng provides two macros to help you in 1.5 and later versions:
+
+ png_uint_32 width = PNG_PASS_COLS(image_width, pass_number);
+ png_uint_32 height = PNG_PASS_ROWS(image_height, pass_number);
+
+Respectively these tell you the width and height of the sub-image
+corresponding to the numbered pass. 'pass' is in in the range 0 to 6 -
+this can be confusing because the specification refers to the same passes
+as 1 to 7! Be careful, you must check both the width and height before
+calling png_read_rows() and not call it for that pass if either is zero.
+
+You can, of course, read each sub-image row by row. If you want to
+produce optimal code to make a pixel-by-pixel transformation of an
+interlaced image this is the best approach; read each row of each pass,
+transform it, and write it out to a new interlaced image.
+
+If you want to de-interlace the image yourself libpng provides further
+macros to help that tell you where to place the pixels in the output image.
+Because the interlacing scheme is rectangular - sub-image pixels are always
+arranged on a rectangular grid - all you need to know for each pass is the
+starting column and row in the output image of the first pixel plus the
+spacing between each pixel. As of libpng 1.5 there are four macros to
+retrieve this information:
+
+ png_uint_32 x = PNG_PASS_START_COL(pass);
+ png_uint_32 y = PNG_PASS_START_ROW(pass);
+ png_uint_32 xStep = 1U << PNG_PASS_COL_SHIFT(pass);
+ png_uint_32 yStep = 1U << PNG_PASS_ROW_SHIFT(pass);
+
+These allow you to write the obvious loop:
+
+ png_uint_32 input_y = 0;
+ png_uint_32 output_y = PNG_PASS_START_ROW(pass);
+
+ while (output_y < output_image_height)
+ {
+ png_uint_32 input_x = 0;
+ png_uint_32 output_x = PNG_PASS_START_COL(pass);
+
+ while (output_x < output_image_width)
+ {
+ image[output_y][output_x] =
+ subimage[pass][input_y][input_x++];
+
+ output_x += xStep;
+ }
+
+ ++input_y;
+ output_y += yStep;
+ }
+
+Notice that the steps between successive output rows and columns are
+returned as shifts. This is possible because the pixels in the subimages
+are always a power of 2 apart - 1, 2, 4 or 8 pixels - in the original
+image. In practice you may need to directly calculate the output coordinate
+given an input coordinate. libpng provides two further macros for this
+purpose:
+
+ png_uint_32 output_x = PNG_COL_FROM_PASS_COL(input_x, pass);
+ png_uint_32 output_y = PNG_ROW_FROM_PASS_ROW(input_y, pass);
+
+Finally a pair of macros are provided to tell you if a particular image
+row or column appears in a given pass:
+
+ int col_in_pass = PNG_COL_IN_INTERLACE_PASS(output_x, pass);
+ int row_in_pass = PNG_ROW_IN_INTERLACE_PASS(output_y, pass);
+
+Bear in mind that you will probably also need to check the width and height
+of the pass in addition to the above to be sure the pass even exists!
+
+With any luck you are convinced by now that you don't want to do your own
+interlace handling. In reality normally the only good reason for doing this
+is if you are processing PNG files on a pixel-by-pixel basis and don't want
+to load the whole file into memory when it is interlaced.
+
+libpng includes a test program, pngvalid, that illustrates reading and
+writing of interlaced images. If you can't get interlacing to work in your
+code and don't want to leave it to libpng (the recommended approach), see
+how pngvalid.c does it.
Finishing a sequential read
@@ -1396,19 +2131,44 @@ low-level interface, you can finish reading the file. If you are interested in comments or time, which may be stored either before or
after the image data, you should pass the separate png_info struct if
you want to keep the comments from before and after the image
-separate. If you are not interested, you can pass NULL.
+separate.
+
+ png_infop end_info = png_create_info_struct(png_ptr);
+
+ if (!end_info)
+ {
+ png_destroy_read_struct(&png_ptr, &info_ptr,
+ (png_infopp)NULL);
+ return (ERROR);
+ }
png_read_end(png_ptr, end_info);
+If you are not interested, you should still call png_read_end()
+but you can pass NULL, avoiding the need to create an end_info structure.
+
+ png_read_end(png_ptr, (png_infop)NULL);
+
+If you don't call png_read_end(), then your file pointer will be
+left pointing to the first chunk after the last IDAT, which is probably
+not what you want if you expect to read something beyond the end of
+the PNG datastream.
+
When you are done, you can free all memory allocated by libpng like this:
png_destroy_read_struct(&png_ptr, &info_ptr,
&end_info);
+or, if you didn't create an end_info structure,
+
+ png_destroy_read_struct(&png_ptr, &info_ptr,
+ (png_infopp)NULL);
+
It is also possible to individually free the info_ptr members that
point to libpng-allocated storage with the following function:
png_free_data(png_ptr, info_ptr, mask, seq)
+
mask - identifies data to be freed, a mask
containing the bitwise OR of one or
more of
@@ -1418,6 +2178,7 @@ point to libpng-allocated storage with the following function: PNG_FREE_SCAL, PNG_FREE_SPLT,
PNG_FREE_TEXT, PNG_FREE_UNKN,
or simply PNG_FREE_ALL
+
seq - sequence number of item to be freed
(-1 for all items)
@@ -1432,16 +2193,18 @@ sPLT, only the n'th item in the structure is freed, where n is "seq". The default behavior is only to free data that was allocated internally
by libpng. This can be changed, so that libpng will not free the data,
or so that it will free data that was allocated by the user with png_malloc()
-or png_zalloc() and passed in via a png_set_*() function, with
+or png_calloc() and passed in via a png_set_*() function, with
png_data_freer(png_ptr, info_ptr, freer, mask)
- mask - which data elements are affected
- same choices as in png_free_data()
+
freer - one of
PNG_DESTROY_WILL_FREE_DATA
PNG_SET_WILL_FREE_DATA
PNG_USER_WILL_FREE_DATA
+ mask - which data elements are affected
+ same choices as in png_free_data()
+
This function only affects data that has already been allocated.
You can call this function after reading the PNG data but before calling
any png_set_*() functions, to control whether the user or the png_set_*()
@@ -1451,7 +2214,7 @@ or png_destroy_*() is supposed to free the data. When the user assumes responsibility for libpng-allocated data, the application must use
png_free() to free it, and when the user transfers responsibility to libpng
for data that the user has allocated, the user must have used png_malloc()
-or png_zalloc() to allocate it.
+or png_calloc() to allocate it.
If you allocated your row_pointers in a single block, as suggested above in
the description of the high level read interface, you must not transfer
@@ -1470,6 +2233,7 @@ it frees. If you need to turn the flag off for a chunk that was freed by your application instead of by libpng, you can use
png_set_invalid(png_ptr, info_ptr, mask);
+
mask - identifies the chunks to be made invalid,
containing the bitwise OR of one or
more of
@@ -1509,21 +2273,24 @@ png_infop info_ptr; png_ptr = png_create_read_struct
(PNG_LIBPNG_VER_STRING, (png_voidp)user_error_ptr,
user_error_fn, user_warning_fn);
+
if (!png_ptr)
return (ERROR);
+
info_ptr = png_create_info_struct(png_ptr);
+
if (!info_ptr)
{
- png_destroy_read_struct(&png_ptr, (png_infopp)NULL,
- (png_infopp)NULL);
- return (ERROR);
+ png_destroy_read_struct(&png_ptr,
+ (png_infopp)NULL, (png_infopp)NULL);
+ return (ERROR);
}
if (setjmp(png_jmpbuf(png_ptr)))
{
- png_destroy_read_struct(&png_ptr, &info_ptr,
- (png_infopp)NULL);
- return (ERROR);
+ png_destroy_read_struct(&png_ptr, &info_ptr,
+ (png_infopp)NULL);
+ return (ERROR);
}
/* This one's new. You can provide functions
@@ -1555,9 +2322,9 @@ png_infop info_ptr; {
if (setjmp(png_jmpbuf(png_ptr)))
{
- png_destroy_read_struct(&png_ptr, &info_ptr,
+ png_destroy_read_struct(&png_ptr, &info_ptr,
(png_infopp)NULL);
- return (ERROR);
+ return (ERROR);
}
/* This one's new also. Simply give it a chunk
@@ -1574,6 +2341,12 @@ png_infop info_ptr; so there.
*/
png_process_data(png_ptr, info_ptr, buffer, length);
+
+ /* At this point you can call png_process_data_skip if
+ you want to handle data the library will skip yourself;
+ it simply returns the number of bytes to skip (and stops
+ libpng skipping that number of bytes on the next
+ png_process_data call).
return 0;
}
@@ -1594,6 +2367,19 @@ png_infop info_ptr; any). You may start getting rows before
png_process_data() returns, so this is your
last chance to prepare for that.
+
+ This is where you turn on interlace handling,
+ assuming you don't want to do it yourself.
+
+ If you need to you can stop the processing of
+ your original input data at this point by calling
+ png_process_data_pause. This returns the number
+ of unprocessed bytes from the last png_process_data
+ call - it is up to you to ensure that the next call
+ sees these bytes again. If you don't want to bother
+ with this you can get libpng to cache the unread
+ bytes by setting the 'save' parameter (see png.h) but
+ then libpng will have to copy the data internally.
*/
}
@@ -1614,14 +2400,22 @@ png_infop info_ptr; supplying them because it may make your life
easier.
- For the non-NULL rows of interlaced images,
+ If you did not turn on interlace handling then
+ the callback is called for each row of each
+ sub-image when the image is interlaced. In this
+ case 'row_num' is the row in the sub-image, not
+ the row in the output image as it is in all other
+ cases.
+
+ For the non-NULL rows of interlaced images when
+ you have switched on libpng interlace handling,
you must call png_progressive_combine_row()
passing in the row and the old row. You can
call this function for NULL rows (it will just
return) and for non-interlaced images (it just
does the memcpy for you) if it will make the
code easier. Thus, you can just do this for
- all cases:
+ all cases if you switch on interlace handling;
*/
png_progressive_combine_row(png_ptr, old_row,
@@ -1635,6 +2429,9 @@ png_infop info_ptr; for interlaced images), you will have to pass
the current row, and the function will combine
the old row and the new row.
+
+ You can also call png_process_data_pause in this
+ callback - see above.
*/
}
@@ -1669,10 +2466,9 @@ using the standard I/O functions, you will need to replace them with custom writing functions. See the discussion under Customizing libpng.
FILE *fp = fopen(file_name, "wb");
+
if (!fp)
- {
return (ERROR);
- }
Next, png_struct and png_info need to be allocated and initialized.
As these can be both relatively large, you may not want to store these
@@ -1685,6 +2481,7 @@ both "png_ptr"; you can call them anything you like, such as png_structp png_ptr = png_create_write_struct
(PNG_LIBPNG_VER_STRING, (png_voidp)user_error_ptr,
user_error_fn, user_warning_fn);
+
if (!png_ptr)
return (ERROR);
@@ -1692,7 +2489,7 @@ both "png_ptr"; you can call them anything you like, such as if (!info_ptr)
{
png_destroy_write_struct(&png_ptr,
- (png_infopp)NULL);
+ (png_infopp)NULL);
return (ERROR);
}
@@ -1718,7 +2515,7 @@ section below for more information on the libpng error handling. if (setjmp(png_jmpbuf(png_ptr)))
{
- png_destroy_write_struct(&png_ptr, &info_ptr);
+ png_destroy_write_struct(&png_ptr, &info_ptr);
fclose(fp);
return (ERROR);
}
@@ -1757,7 +2554,7 @@ called after each row has been written, which you can use to control a progress meter or the like. It's demonstrated in pngtest.c.
You must supply a function
- void write_row_callback(png_ptr, png_uint_32 row,
+ void write_row_callback(png_structp png_ptr, png_uint_32 row,
int pass);
{
/* put your code here */
@@ -1769,6 +2566,20 @@ To inform libpng about your function, use png_set_write_status_fn(png_ptr, write_row_callback);
+When this function is called the row has already been completely processed and
+it has also been written out. The 'row' and 'pass' refer to the next row to be
+handled. For the
+non-interlaced case the row that was just handled is simply one less than the
+passed in row number, and pass will always be 0. For the interlaced case the
+same applies unless the row value is 0, in which case the row just handled was
+the last one from one of the preceding passes. Because interlacing may skip a
+pass you cannot be sure that the preceding pass is just 'pass-1', if you really
+need to know what the last pass is record (row,pass) from the callback and use
+the last recorded value each time.
+
+As with the user transform you can find the output row using the
+PNG_ROW_FROM_PASS_ROW macro.
+
You now have the option of modifying how the compression library will
run. The following functions are mainly for testing, but may be useful
in some cases, like if you need to write PNG files extremely fast and
@@ -1788,7 +2599,8 @@ filter types. /* turn on or off filtering, and/or choose
specific filters. You can use either a single
PNG_FILTER_VALUE_NAME or the bitwise OR of one
- or more PNG_FILTER_NAME masks. */
+ or more PNG_FILTER_NAME masks.
+ */
png_set_filter(png_ptr, 0,
PNG_FILTER_NONE | PNG_FILTER_VALUE_NONE |
PNG_FILTER_SUB | PNG_FILTER_VALUE_SUB |
@@ -1797,11 +2609,10 @@ filter types. PNG_FILTER_PAETH | PNG_FILTER_VALUE_PAETH|
PNG_ALL_FILTERS);
-If an application
-wants to start and stop using particular filters during compression,
-it should start out with all of the filters (to ensure that the previous
-row of pixels will be stored in case it's needed later), and then add
-and remove them after the start of compression.
+If an application wants to start and stop using particular filters during
+compression, it should start out with all of the filters (to ensure that
+the previous row of pixels will be stored in case it's needed later),
+and then add and remove them after the start of compression.
If you are writing a PNG datastream that is to be embedded in a MNG
datastream, the second parameter can be either 0 or 64.
@@ -1813,11 +2624,13 @@ which changes how much time zlib spends on trying to compress the image data. See the Compression Library (zlib.h and algorithm.txt, distributed
with zlib) for details on the compression levels.
- /* set the zlib compression level */
+ #include zlib.h
+
+ /* Set the zlib compression level */
png_set_compression_level(png_ptr,
Z_BEST_COMPRESSION);
- /* set other zlib parameters */
+ /* Set other zlib parameters for compressing IDAT */
png_set_compression_mem_level(png_ptr, 8);
png_set_compression_strategy(png_ptr,
Z_DEFAULT_STRATEGY);
@@ -1825,7 +2638,15 @@ with zlib) for details on the compression levels. png_set_compression_method(png_ptr, 8);
png_set_compression_buffer_size(png_ptr, 8192)
-extern PNG_EXPORT(void,png_set_zbuf_size)
+ /* Set zlib parameters for text compression
+ * If you don't call these, the parameters
+ * fall back on those defined for IDAT chunks
+ */
+ png_set_text_compression_mem_level(png_ptr, 8);
+ png_set_text_compression_strategy(png_ptr,
+ Z_DEFAULT_STRATEGY);
+ png_set_text_compression_window_bits(png_ptr, 15);
+ png_set_text_compression_method(png_ptr, 8);
Setting the contents of info for output
@@ -1845,16 +2666,20 @@ Some of the more important parts of the png_info are: png_set_IHDR(png_ptr, info_ptr, width, height,
bit_depth, color_type, interlace_type,
compression_type, filter_method)
+
width - holds the width of the image
in pixels (up to 2^31).
+
height - holds the height of the image
in pixels (up to 2^31).
+
bit_depth - holds the bit depth of one of the
image channels.
(valid values are 1, 2, 4, 8, 16
and depend also on the
color_type. See also significant
bits (sBIT) below).
+
color_type - describes which color/alpha
channels are present.
PNG_COLOR_TYPE_GRAY
@@ -1874,8 +2699,10 @@ Some of the more important parts of the png_info are: interlace_type - PNG_INTERLACE_NONE or
PNG_INTERLACE_ADAM7
+
compression_type - (must be
PNG_COMPRESSION_TYPE_DEFAULT)
+
filter_method - (must be PNG_FILTER_TYPE_DEFAULT
or, if you are writing a PNG to
be embedded in a MNG datastream,
@@ -1893,15 +2720,44 @@ width, height, bit_depth, and color_type must be the same in each call. png_set_PLTE(png_ptr, info_ptr, palette,
num_palette);
+
palette - the palette for the file
(array of png_color)
num_palette - number of entries in the palette
- png_set_gAMA(png_ptr, info_ptr, gamma);
- gamma - the gamma the image was created
- at (PNG_INFO_gAMA)
+ png_set_gAMA(png_ptr, info_ptr, file_gamma);
+ png_set_gAMA_fixed(png_ptr, info_ptr, int_file_gamma);
+
+ file_gamma - the gamma at which the image was
+ created (PNG_INFO_gAMA)
+
+ int_file_gamma - 100,000 times the gamma at which
+ the image was created
+
+ png_set_cHRM(png_ptr, info_ptr, white_x, white_y, red_x, red_y,
+ green_x, green_y, blue_x, blue_y)
+ png_set_cHRM_XYZ(png_ptr, info_ptr, red_X, red_Y, red_Z, green_X,
+ green_Y, green_Z, blue_X, blue_Y, blue_Z)
+ png_set_cHRM_fixed(png_ptr, info_ptr, int_white_x, int_white_y,
+ int_red_x, int_red_y, int_green_x, int_green_y,
+ int_blue_x, int_blue_y)
+ png_set_cHRM_XYZ_fixed(png_ptr, info_ptr, int_red_X, int_red_Y,
+ int_red_Z, int_green_X, int_green_Y, int_green_Z,
+ int_blue_X, int_blue_Y, int_blue_Z)
+
+ {white,red,green,blue}_{x,y}
+ A color space encoding specified using the chromaticities
+ of the end points and the white point.
+
+ {red,green,blue}_{X,Y,Z}
+ A color space encoding specified using the encoding end
+ points - the CIE tristimulus specification of the intended
+ color of the red, green and blue channels in the PNG RGB
+ data. The white point is simply the sum of the three end
+ points.
png_set_sRGB(png_ptr, info_ptr, srgb_intent);
+
srgb_intent - the rendering intent
(PNG_INFO_sRGB) The presence of
the sRGB chunk means that the pixel
@@ -1921,6 +2777,7 @@ width, height, bit_depth, and color_type must be the same in each call. png_set_sRGB_gAMA_and_cHRM(png_ptr, info_ptr,
srgb_intent);
+
srgb_intent - the rendering intent
(PNG_INFO_sRGB) The presence of the
sRGB chunk means that the pixel
@@ -1931,17 +2788,22 @@ width, height, bit_depth, and color_type must be the same in each call. written.
png_set_iCCP(png_ptr, info_ptr, name, compression_type,
- profile, proflen);
- name - The profile name.
- compression - The compression type; always
- PNG_COMPRESSION_TYPE_BASE for PNG 1.0.
- You may give NULL to this argument to
- ignore it.
- profile - International Color Consortium color
- profile data. May contain NULs.
- proflen - length of profile data in bytes.
+ profile, proflen);
+
+ name - The profile name.
+
+ compression_type - The compression type; always
+ PNG_COMPRESSION_TYPE_BASE for PNG 1.0.
+ You may give NULL to this argument to
+ ignore it.
+
+ profile - International Color Consortium color
+ profile data. May contain NULs.
+
+ proflen - length of profile data in bytes.
png_set_sBIT(png_ptr, info_ptr, sig_bit);
+
sig_bit - the number of significant bits for
(PNG_INFO_sBIT) each of the gray, red,
green, and blue channels, whichever are
@@ -1950,30 +2812,38 @@ width, height, bit_depth, and color_type must be the same in each call. png_set_tRNS(png_ptr, info_ptr, trans_alpha,
num_trans, trans_color);
+
trans_alpha - array of alpha (transparency)
entries for palette (PNG_INFO_tRNS)
+
+ num_trans - number of transparent entries
+ (PNG_INFO_tRNS)
+
trans_color - graylevel or color sample values
(in order red, green, blue) of the
single transparent color for
non-paletted images (PNG_INFO_tRNS)
- num_trans - number of transparent entries
- (PNG_INFO_tRNS)
png_set_hIST(png_ptr, info_ptr, hist);
- (PNG_INFO_hIST)
+
hist - histogram of palette (array of
- png_uint_16)
+ png_uint_16) (PNG_INFO_hIST)
png_set_tIME(png_ptr, info_ptr, mod_time);
+
mod_time - time image was last modified
(PNG_VALID_tIME)
png_set_bKGD(png_ptr, info_ptr, background);
- background - background color (PNG_VALID_bKGD)
+
+ background - background color (of type
+ png_color_16p) (PNG_VALID_bKGD)
png_set_text(png_ptr, info_ptr, text_ptr, num_text);
+
text_ptr - array of png_text holding image
comments
+
text_ptr[i].compression - type of compression used
on "text" PNG_TEXT_COMPRESSION_NONE
PNG_TEXT_COMPRESSION_zTXt
@@ -1991,14 +2861,21 @@ width, height, bit_depth, and color_type must be the same in each call. empty for unknown).
text_ptr[i].translated_keyword - keyword in UTF-8 (NULL
or empty for unknown).
+
Note that the itxt_length, lang, and lang_key
- members of the text_ptr structure only exist
- when the library is built with iTXt chunk support.
+ members of the text_ptr structure only exist when the
+ library is built with iTXt chunk support. Prior to
+ libpng-1.4.0 the library was built by default without
+ iTXt support. Also note that when iTXt is supported,
+ they contain NULL pointers when the "compression"
+ field contains PNG_TEXT_COMPRESSION_NONE or
+ PNG_TEXT_COMPRESSION_zTXt.
num_text - number of comments
png_set_sPLT(png_ptr, info_ptr, &palette_ptr,
num_spalettes);
+
palette_ptr - array of png_sPLT_struct structures
to be added to the list of palettes
in the info structure.
@@ -2007,35 +2884,49 @@ width, height, bit_depth, and color_type must be the same in each call. png_set_oFFs(png_ptr, info_ptr, offset_x, offset_y,
unit_type);
+
offset_x - positive offset from the left
edge of the screen
+
offset_y - positive offset from the top
edge of the screen
+
unit_type - PNG_OFFSET_PIXEL, PNG_OFFSET_MICROMETER
png_set_pHYs(png_ptr, info_ptr, res_x, res_y,
unit_type);
+
res_x - pixels/unit physical resolution
in x direction
+
res_y - pixels/unit physical resolution
in y direction
+
unit_type - PNG_RESOLUTION_UNKNOWN,
PNG_RESOLUTION_METER
png_set_sCAL(png_ptr, info_ptr, unit, width, height)
+
unit - physical scale units (an integer)
+
width - width of a pixel in physical scale units
+
height - height of a pixel in physical scale units
(width and height are doubles)
png_set_sCAL_s(png_ptr, info_ptr, unit, width, height)
+
unit - physical scale units (an integer)
+
width - width of a pixel in physical scale units
+ expressed as a string
+
height - height of a pixel in physical scale units
(width and height are strings like "2.54")
png_set_unknown_chunks(png_ptr, info_ptr, &unknowns,
num_unknowns)
+
unknowns - array of png_unknown_chunk
structures holding unknown chunks
unknowns[i].name - name of unknown chunk
@@ -2070,25 +2961,34 @@ Because tEXt and zTXt chunks don't have a language field, if you specify PNG_TEXT_COMPRESSION_NONE or PNG_TEXT_COMPRESSION_zTXt
any language code or translated keyword will not be written out.
-Until text gets around 1000 bytes, it is not worth compressing it.
+Until text gets around a few hundred bytes, it is not worth compressing it.
After the text has been written out to the file, the compression type
is set to PNG_TEXT_COMPRESSION_NONE_WR or PNG_TEXT_COMPRESSION_zTXt_WR,
so that it isn't written out again at the end (in case you are calling
-png_write_end() with the same struct.
+png_write_end() with the same struct).
The keywords that are given in the PNG Specification are:
Title Short (one line) title or
caption for image
+
Author Name of image's creator
+
Description Description of image (possibly long)
+
Copyright Copyright notice
+
Creation Time Time of original image creation
(usually RFC 1123 format, see below)
+
Software Software used to create the image
+
Disclaimer Legal disclaimer
+
Warning Warning of nature of content
+
Source Device used to create the image
+
Comment Miscellaneous comment; conversion
from other image format
@@ -2132,8 +3032,8 @@ tEXt chunk use RFC 1123 format dates (e.g. "22 May 1997 18:07:10 GMT"), although this isn't a requirement. Unlike the tIME chunk, the
"Creation Time" tEXt chunk is not expected to be automatically changed
by the software. To facilitate the use of RFC 1123 dates, a function
-png_convert_to_rfc1123(png_timep) is provided to convert from PNG
-time to an RFC 1123 format string.
+png_convert_to_rfc1123(png_ptr, png_timep) is provided to convert
+from PNG time to an RFC 1123 format string.
Writing unknown chunks
@@ -2258,17 +3158,19 @@ file so that decoders can recover the original data if desired. /* Set the true bit depth of the image data */
if (color_type & PNG_COLOR_MASK_COLOR)
{
- sig_bit.red = true_bit_depth;
- sig_bit.green = true_bit_depth;
- sig_bit.blue = true_bit_depth;
+ sig_bit.red = true_bit_depth;
+ sig_bit.green = true_bit_depth;
+ sig_bit.blue = true_bit_depth;
}
+
else
{
- sig_bit.gray = true_bit_depth;
+ sig_bit.gray = true_bit_depth;
}
+
if (color_type & PNG_COLOR_MASK_ALPHA)
{
- sig_bit.alpha = true_bit_depth;
+ sig_bit.alpha = true_bit_depth;
}
png_set_sBIT(png_ptr, info_ptr, &sig_bit);
@@ -2280,7 +3182,7 @@ is required by PNG. png_set_shift(png_ptr, &sig_bit);
-PNG files store 16 bit pixels in network byte order (big-endian,
+PNG files store 16-bit pixels in network byte order (big-endian,
ie. most significant bits first). This code would be used if they are
supplied the other way (little-endian, i.e. least significant bits
first, the way PCs store them):
@@ -2314,11 +3216,24 @@ with You must supply the function
- void write_transform_fn(png_ptr ptr, row_info_ptr
+ void write_transform_fn(png_structp png_ptr, png_row_infop
row_info, png_bytep data)
See pngtest.c for a working example. Your function will be called
-before any of the other transformations are processed.
+before any of the other transformations are processed. If supported
+libpng also supplies an information routine that may be called from
+your callback:
+
+ png_get_current_row_number(png_ptr);
+ png_get_current_pass_number(png_ptr);
+
+This returns the current row passed to the transform. With interlaced
+images the value returned is the row in the input sub-image image. Use
+PNG_ROW_FROM_PASS_ROW(row, pass) and PNG_COL_FROM_PASS_COL(col, pass) to
+find the output pixel (x,y) given an interlaced sub-image pixel (row,col,pass).
+
+The discussion of interlace handling above contains more information on how to
+use these values.
You can also set up a pointer to a user structure for use by your
callback function.
@@ -2400,25 +3315,39 @@ for details of which pixels to write when. If you don't want libpng to handle the interlacing details, just
use png_set_interlace_handling() and call png_write_rows() the
-correct number of times to write all seven sub-images.
+correct number of times to write all the sub-images
+(png_set_interlace_handling() returns the number of sub-images.)
If you want libpng to build the sub-images, call this before you start
writing any rows:
- number_of_passes =
- png_set_interlace_handling(png_ptr);
+ number_of_passes = png_set_interlace_handling(png_ptr);
This will return the number of passes needed. Currently, this is seven,
but may change if another interlace type is added.
Then write the complete image number_of_passes times.
- png_write_rows(png_ptr, row_pointers,
- number_of_rows);
+ png_write_rows(png_ptr, row_pointers, number_of_rows);
-As some of these rows are not used, and thus return immediately, you may
-want to read about interlacing in the PNG specification, and only update
-the rows that are actually used.
+Think carefully before you write an interlaced image. Typically code that
+reads such images reads all the image data into memory, uncompressed, before
+doing any processing. Only code that can display an image on the fly can
+take advantage of the interlacing and even then the image has to be exactly
+the correct size for the output device, because scaling an image requires
+adjacent pixels and these are not available until all the passes have been
+read.
+
+If you do write an interlaced image you will hardly ever need to handle
+the interlacing yourself. Call png_set_interlace_handling() and use the
+approach described above.
+
+The only time it is conceivable that you will really need to write an
+interlaced image pass-by-pass is when you have read one pass by pass and
+made some pixel-by-pixel transformation to it, as described in the read
+code above. In this case use the PNG_PASS_ROWS and PNG_PASS_COLS macros
+to determine the size of each sub-image in turn and simply write the rows
+you obtained from the read code.
Finishing a sequential write
@@ -2437,6 +3366,7 @@ It is also possible to individually free the info_ptr members that point to libpng-allocated storage with the following function:
png_free_data(png_ptr, info_ptr, mask, seq)
+
mask - identifies data to be freed, a mask
containing the bitwise OR of one or
more of
@@ -2446,6 +3376,7 @@ point to libpng-allocated storage with the following function: PNG_FREE_SCAL, PNG_FREE_SPLT,
PNG_FREE_TEXT, PNG_FREE_UNKN,
or simply PNG_FREE_ALL
+
seq - sequence number of item to be freed
(-1 for all items)
@@ -2464,22 +3395,25 @@ png_destroy_write_struct(). The default behavior is only to free data that was allocated internally
by libpng. This can be changed, so that libpng will not free the data,
or so that it will free data that was allocated by the user with png_malloc()
-or png_zalloc() and passed in via a png_set_*() function, with
+or png_calloc() and passed in via a png_set_*() function, with
png_data_freer(png_ptr, info_ptr, freer, mask)
- mask - which data elements are affected
- same choices as in png_free_data()
+
freer - one of
PNG_DESTROY_WILL_FREE_DATA
PNG_SET_WILL_FREE_DATA
PNG_USER_WILL_FREE_DATA
+ mask - which data elements are affected
+ same choices as in png_free_data()
+
For example, to transfer responsibility for some data from a read structure
to a write structure, you could use
png_data_freer(read_ptr, read_info_ptr,
PNG_USER_WILL_FREE_DATA,
PNG_FREE_PLTE|PNG_FREE_tRNS|PNG_FREE_hIST)
+
png_data_freer(write_ptr, write_info_ptr,
PNG_DESTROY_WILL_FREE_DATA,
PNG_FREE_PLTE|PNG_FREE_tRNS|PNG_FREE_hIST)
@@ -2497,7 +3431,7 @@ When the user assumes responsibility for libpng-allocated data, the application must use
png_free() to free it, and when the user transfers responsibility to libpng
for data that the user has allocated, the user must have used png_malloc()
-or png_zalloc() to allocate it.
+or png_calloc() to allocate it.
If you allocated text_ptr.text, text_ptr.lang, and text_ptr.translated_keyword
separately, do not transfer responsibility for freeing text_ptr to libpng,
@@ -2525,10 +3459,13 @@ in pngmem.c, pngrio.c, pngwio.c, and pngerror.c, respectively. To change these functions, call the appropriate png_set_*_fn() function.
Memory allocation is done through the functions png_malloc(), png_calloc(),
-and png_free(). These currently just call the standard C functions.
-png_calloc() calls png_malloc() and then png_memset() to clear the newly
-allocated memory to zero. If your pointers can't access more then 64K
-at a time, you will want to set MAXSEG_64K in zlib.h. Since it is
+and png_free(). The png_malloc() and png_free() functions currently just
+call the standard C functions and png_calloc() calls png_malloc() and then
+clears the newly allocated memory to zero; note that png_calloc(png_ptr, size)
+is not the same as the calloc(number, size) function provided by stdlib.h.
+There is limited support for certain systems with segmented memory
+architectures and the types of pointers declared by png.h match this; you
+will have to use appropriate pointers in your application. Since it is
unlikely that the method of handling memory allocation on a platform
will change between applications, these functions must be modified in
the library at compile time. If you prefer to use a different method
@@ -2543,6 +3480,7 @@ Your replacement memory functions must have prototypes as follows: png_voidp malloc_fn(png_structp png_ptr,
png_alloc_size_t size);
+
void free_fn(png_structp png_ptr, png_voidp ptr);
Your malloc_fn() must return NULL in case of failure. The png_malloc()
@@ -2575,8 +3513,10 @@ The replacement I/O functions must have prototypes as follows: void user_read_data(png_structp png_ptr,
png_bytep data, png_size_t length);
+
void user_write_data(png_structp png_ptr,
png_bytep data, png_size_t length);
+
void user_flush_data(png_structp png_ptr);
The user_read_data() function is responsible for detecting and
@@ -2621,6 +3561,7 @@ parameters as follows: void user_error_fn(png_structp png_ptr,
png_const_charp error_msg);
+
void user_warning_fn(png_structp png_ptr,
png_const_charp warning_msg);
@@ -2631,7 +3572,8 @@ However, there are some uncertainties about the status of local variables after a longjmp, so the user may want to be careful about doing anything
after setjmp returns non-zero besides returning itself. Consult your
compiler documentation for more details. For an alternative approach, you
-may wish to use the "cexcept" facility (see http://cexcept.sourceforge.net).
+may wish to use the "cexcept" facility (see http://cexcept.sourceforge.net),
+which is illustrated in pngvalid.c and in contrib/visupng.
Custom chunks
@@ -2649,8 +3591,11 @@ and look at how other chunks were designed, so you can do things similarly. Second, check out the sections of libpng that read and
write chunks. Try to find a chunk that is similar to yours and use
it as a template. More details can be found in the comments inside
-the code. It is best to handle unknown chunks in a generic method,
-via callback functions, instead of by modifying libpng functions.
+the code. It is best to handle private or unknown chunks in a generic method,
+via callback functions, instead of by modifying libpng functions. This
+is illustrated in pngtest.c, which uses a callback function to handle a
+private "vpAg" chunk and the new "sTER" chunk, which are both unknown to
+libpng.
If you wish to write your own transformation for the data, look through
the part of the code that does the transformations, and check out some of
@@ -2658,7 +3603,7 @@ the simpler ones to get an idea of how they work. Try to find a similar transformation to the one you want to add and copy off of it. More details
can be found in the comments inside the code itself.
-Configuring for 16 bit platforms
+Configuring for 16-bit platforms
You will want to look into zconf.h to tell zlib (and thus libpng) that
it cannot allocate more then 64K at a time. Even if you can, the memory
@@ -2678,8 +3623,8 @@ defined, and FAR gets defined to far in pngconf.h, and you should be all set. Everything in the library (except for zlib's structure) is
expecting far data. You must use the typedefs with the p or pp on
the end for pointers (or at least look at them and be careful). Make
-note that the rows of data are defined as png_bytepp, which is an
-unsigned char far * far *.
+note that the rows of data are defined as png_bytepp, which is
+an "unsigned char far * far *".
Configuring for gui/windowing platforms:
@@ -2697,7 +3642,10 @@ or delete an include, this is the place to do it. The includes that are not needed outside libpng are placed in pngpriv.h,
which is only used by the routines inside libpng itself.
The files in libpng proper only include pngpriv.h and png.h, which
-in turn includes pngconf.h.
+in turn includes pngconf.h and, as of libpng-1.5.0, pnglibconf.h.
+As of libpng-1.5.0, pngpriv.h also includes three other private header
+files, pngstruct.h, pnginfo.h, and pngdebug.h, which contain material
+that previously appeared in the public headers.
Configuring zlib:
@@ -2713,6 +3661,7 @@ specify no compression (Z_NO_COMPRESSION = 0), but this would create files larger than just storing the raw bitmap. You can specify the
compression level by calling:
+ #include zlib.h
png_set_compression_level(png_ptr, level);
Another useful one is to reduce the memory level used by the library.
@@ -2723,19 +3672,43 @@ other things, lower levels will result in sections of incompressible data being emitted in smaller stored blocks, with a correspondingly
larger relative overhead of up to 15% in the worst case.
+ #include zlib.h
png_set_compression_mem_level(png_ptr, level);
The other functions are for configuring zlib. They are not recommended
for normal use and may result in writing an invalid PNG file. See
zlib.h for more information on what these mean.
+ #include zlib.h
png_set_compression_strategy(png_ptr,
strategy);
+
png_set_compression_window_bits(png_ptr,
window_bits);
+
png_set_compression_method(png_ptr, method);
+
png_set_compression_buffer_size(png_ptr, size);
+As of libpng version 1.5.4, additional APIs became
+available to set these separately for non-IDAT
+compressed chunks such as zTXt, iTXt, and iCCP:
+
+ #include zlib.h
+ #if PNG_LIBPNG_VER >= 10504
+ png_set_text_compression_level(png_ptr, level);
+
+ png_set_text_compression_mem_level(png_ptr, level);
+
+ png_set_text_compression_strategy(png_ptr,
+ strategy);
+
+ png_set_text_compression_window_bits(png_ptr,
+ window_bits);
+
+ png_set_text_compression_method(png_ptr, method);
+ #endif
+
Controlling row filtering
If you want to control whether libpng uses filtering or not, which
@@ -2822,6 +3795,8 @@ before recompiling libpng and save yourself code and data space, or you can turn off individual capabilities with defines that begin with
PNG_NO_.
+In libpng-1.5.0 and later, the #define's are in pnglibconf.h instead.
+
You can also turn all of the transforms and ancillary chunk capabilities
off en masse with compiler directives that define
PNG_NO_READ[or WRITE]_TRANSFORMS, or PNG_NO_READ[or WRITE]_ANCILLARY_CHUNKS,
@@ -2839,8 +3814,8 @@ capability, which you'll still have). All the reading and writing specific code are in separate files, so the
linker should only grab the files it needs. However, if you want to
make sure, or if you are building a stand alone library, all the
-reading files start with pngr and all the writing files start with
-pngw. The files that don't match either (like png.c, pngtrans.c, etc.)
+reading files start with "pngr" and all the writing files start with "pngw".
+The files that don't match either (like png.c, pngtrans.c, etc.)
are used for both reading and writing, and always need to be included.
The progressive reader is in pngpread.c
@@ -2874,8 +3849,8 @@ according to printf-style formatting directives. For example, is expanded to
- if(PNG_DEBUG > 2)
- fprintf(PNG_DEBUG_FILE, "foo=%d\n", foo);
+ if (PNG_DEBUG > 2)
+ fprintf(PNG_DEBUG_FILE, "foo=%d\n", foo);
When PNG_DEBUG is defined but is zero, the macros aren't defined, but you
can still use PNG_DEBUG to control your own debugging:
@@ -2896,11 +3871,13 @@ Libpng can support some of these extensions. To enable them, use the png_permit_mng_features() function:
feature_set = png_permit_mng_features(png_ptr, mask)
+
mask is a png_uint_32 containing the bitwise OR of the
features you want to enable. These include
PNG_FLAG_MNG_EMPTY_PLTE
PNG_FLAG_MNG_FILTER_64
PNG_ALL_MNG_FEATURES
+
feature_set is a png_uint_32 that is the bitwise AND of
your mask with the set of MNG features that is
supported by the version of libpng that you are using.
@@ -2925,7 +3902,7 @@ still alive and well, but they have moved on to other things. The old libpng functions png_read_init(), png_write_init(),
png_info_init(), png_read_destroy(), and png_write_destroy() have been
moved to PNG_INTERNAL in version 0.95 to discourage their use. These
-functions will be removed from libpng version 2.0.0.
+functions will be removed from libpng version 1.4.0.
The preferred method of creating and initializing the libpng structures is
via the png_create_read_struct(), png_create_write_struct(), and
@@ -2957,6 +3934,9 @@ The number libpng_vn is constructed from the major version, minor version with leading zero, and release number with leading zero,
(e.g., libpng_vn for version 1.0.7 is 10007).
+Note that this function does not take a png_ptr, so you can call it
+before you've created one.
+
You can also check which version of png.h you used when compiling your
application:
@@ -3120,7 +4100,13 @@ and png_memset(), respectively. The function png_set_gray_1_2_4_to_8() was removed. It has been
deprecated since libpng-1.0.18 and 1.2.9, when it was replaced with
png_set_expand_gray_1_2_4_to_8() because the former function also
-expanded palette images.
+expanded any tRNS chunk to an alpha channel.
+
+Macros for png_get_uint_16, png_get_uint_32, and png_get_int_32
+were added and are used by default instead of the corresponding
+functions. Unfortunately,
+from libpng-1.4.0 until 1.4.4, the png_get_uint_16 macro (but not the
+function) incorrectly returned a value of type png_uint_32.
We changed the prototype for png_malloc() from
png_malloc(png_structp png_ptr, png_uint_32 size)
@@ -3130,7 +4116,7 @@ to This also applies to the prototype for the user replacement malloc_fn().
The png_calloc() function was added and is used in place of
-of "png_malloc(); png_memset();" except in the case in png_read_png()
+of "png_malloc(); memset();" except in the case in png_read_png()
where the array consists of pointers; in this case a "for" loop is used
after the png_malloc() to set the pointers to NULL, to give robust.
behavior in case the application runs out of memory part-way through
@@ -3146,20 +4132,340 @@ png_set_strip_error_numbers() was removed from the library by default. The png_zalloc() and png_zfree() functions are no longer exported.
The png_zalloc() function no longer zeroes out the memory that it
-allocates.
+allocates. Applications that called png_zalloc(png_ptr, number, size)
+can call png_calloc(png_ptr, number*size) instead, and can call
+png_free() instead of png_zfree().
Support for dithering was disabled by default in libpng-1.4.0, because
-been well tested and doesn't actually "dither". The code was not
+it has not been well tested and doesn't actually "dither".
+The code was not
removed, however, and could be enabled by building libpng with
PNG_READ_DITHER_SUPPORTED defined. In libpng-1.4.2, this support
was reenabled, but the function was renamed png_set_quantize() to
reflect more accurately what it actually does. At the same time,
the PNG_DITHER_[RED,GREEN_BLUE]_BITS macros were also renamed to
-PNG_QUANTIZE_[RED,GREEN,BLUE]_BITS.
+PNG_QUANTIZE_[RED,GREEN,BLUE]_BITS, and PNG_READ_DITHER_SUPPORTED
+was renamed to PNG_READ_QUANTIZE_SUPPORTED.
We removed the trailing '.' from the warning and error messages.
-X. Detecting libpng
+X. Changes to Libpng from version 1.4.x to 1.5.x
+
+From libpng-1.4.0 until 1.4.4, the png_get_uint_16 macro (but not the
+function) incorrectly returned a value of type png_uint_32.
+
+Checking for invalid palette index on read or write was added at libpng
+1.5.10. When an invalid index is found, libpng issues a benign error.
+This is enabled by default but can be disabled in each png_ptr with
+
+ png_set_check_for_invalid_index(png_ptr, allowed);
+
+ allowed - one of
+ 0: disable
+ 1: enable
+
+A. Changes that affect users of libpng
+
+There are no substantial API changes between the non-deprecated parts of
+the 1.4.5 API and the 1.5.0 API; however, the ability to directly access
+members of the main libpng control structures, png_struct and png_info,
+deprecated in earlier versions of libpng, has been completely removed from
+libpng 1.5.
+
+We no longer include zlib.h in png.h. Applications that need access
+to information in zlib.h will need to add the '#include "zlib.h"'
+directive. It does not matter whether it is placed prior to or after
+the '"#include png.h"' directive.
+
+The png_sprintf(), png_strcpy(), and png_strncpy() macros are no longer used
+and were removed.
+
+We moved the png_strlen(), png_memcpy(), png_memset(), and png_memcmp()
+macros into a private header file (pngpriv.h) that is not accessible to
+applications.
+
+In png_get_iCCP, the type of "profile" was changed from png_charpp
+to png_bytepp, and in png_set_iCCP, from png_charp to png_const_bytep.
+
+There are changes of form in png.h, including new and changed macros to
+declare parts of the API. Some API functions with arguments that are
+pointers to data not modified within the function have been corrected to
+declare these arguments with PNG_CONST.
+
+Much of the internal use of C macros to control the library build has also
+changed and some of this is visible in the exported header files, in
+particular the use of macros to control data and API elements visible
+during application compilation may require significant revision to
+application code. (It is extremely rare for an application to do this.)
+
+Any program that compiled against libpng 1.4 and did not use deprecated
+features or access internal library structures should compile and work
+against libpng 1.5, except for the change in the prototype for
+png_get_iCCP() and png_set_iCCP() API functions mentioned above.
+
+libpng 1.5.0 adds PNG_ PASS macros to help in the reading and writing of
+interlaced images. The macros return the number of rows and columns in
+each pass and information that can be used to de-interlace and (if
+absolutely necessary) interlace an image.
+
+libpng 1.5.0 adds an API png_longjmp(png_ptr, value). This API calls
+the application-provided png_longjmp_ptr on the internal, but application
+initialized, longjmp buffer. It is provided as a convenience to avoid
+the need to use the png_jmpbuf macro, which had the unnecessary side
+effect of resetting the internal png_longjmp_ptr value.
+
+libpng 1.5.0 includes a complete fixed point API. By default this is
+present along with the corresponding floating point API. In general the
+fixed point API is faster and smaller than the floating point one because
+the PNG file format used fixed point, not floating point. This applies
+even if the library uses floating point in internal calculations. A new
+macro, PNG_FLOATING_ARITHMETIC_SUPPORTED, reveals whether the library
+uses floating point arithmetic (the default) or fixed point arithmetic
+internally for performance critical calculations such as gamma correction.
+In some cases, the gamma calculations may produce slightly different
+results. This has changed the results in png_rgb_to_gray and in alpha
+composition (png_set_background for example). This applies even if the
+original image was already linear (gamma == 1.0) and, therefore, it is
+not necessary to linearize the image. This is because libpng has *not*
+been changed to optimize that case correctly, yet.
+
+Fixed point support for the sCAL chunk comes with an important caveat;
+the sCAL specification uses a decimal encoding of floating point values
+and the accuracy of PNG fixed point values is insufficient for
+representation of these values. Consequently a "string" API
+(png_get_sCAL_s and png_set_sCAL_s) is the only reliable way of reading
+arbitrary sCAL chunks in the absence of either the floating point API or
+internal floating point calculations.
+
+Applications no longer need to include the optional distribution header
+file pngusr.h or define the corresponding macros during application
+build in order to see the correct variant of the libpng API. From 1.5.0
+application code can check for the corresponding _SUPPORTED macro:
+
+#ifdef PNG_INCH_CONVERSIONS_SUPPORTED
+ /* code that uses the inch conversion APIs. */
+#endif
+
+This macro will only be defined if the inch conversion functions have been
+compiled into libpng. The full set of macros, and whether or not support
+has been compiled in, are available in the header file pnglibconf.h.
+This header file is specific to the libpng build. Notice that prior to
+1.5.0 the _SUPPORTED macros would always have the default definition unless
+reset by pngusr.h or by explicit settings on the compiler command line.
+These settings may produce compiler warnings or errors in 1.5.0 because
+of macro redefinition.
+
+From libpng-1.4.0 until 1.4.4, the png_get_uint_16 macro (but not the
+function) incorrectly returned a value of type png_uint_32. libpng 1.5.0
+is consistent with the implementation in 1.4.5 and 1.2.x (where the macro
+did not exist.)
+
+Applications can now choose whether to use these macros or to call the
+corresponding function by defining PNG_USE_READ_MACROS or
+PNG_NO_USE_READ_MACROS before including png.h. Notice that this is
+only supported from 1.5.0 -defining PNG_NO_USE_READ_MACROS prior to 1.5.0
+will lead to a link failure.
+
+Prior to libpng-1.5.4, the zlib compressor used the same set of parameters
+when compressing the IDAT data and textual data such as zTXt and iCCP.
+In libpng-1.5.4 we reinitialized the zlib stream for each type of data.
+We added five png_set_text_*() functions for setting the parameters to
+use with textual data.
+
+Prior to libpng-1.5.4, the PNG_READ_16_TO_8_ACCURATE_SCALE_SUPPORTED
+option was off by default, and slightly inaccurate scaling occurred.
+This option can no longer be turned off, and the choice of accurate
+or inaccurate 16-to-8 scaling is by using the new png_set_scale_16_to_8()
+API for accurate scaling or the old png_set_strip_16_to_8() API for simple
+chopping.
+
+Prior to libpng-1.5.4, the png_set_user_limits() function could only be
+used to reduce the width and height limits from the value of
+PNG_USER_WIDTH_MAX and PNG_USER_HEIGHT_MAX, although this document said
+that it could be used to override them. Now this function will reduce or
+increase the limits.
+
+Starting in libpng-1.5.10, the user limits can be set en masse with the
+configuration option PNG_SAFE_LIMITS_SUPPORTED. If this option is enabled,
+a set of "safe" limits is applied in pngpriv.h. These can be overridden by
+application calls to png_set_user_limits(), png_set_user_chunk_cache_max(),
+and/or png_set_user_malloc_max() that increase or decrease the limits. Also,
+in libpng-1.5.10 the default width and height limits were increased
+from 1,000,000 to 0x7ffffff (i.e., made unlimited). Therefore, the
+limits are now
+ default safe
+ png_user_width_max 0x7fffffff 1,000,000
+ png_user_height_max 0x7fffffff 1,000,000
+ png_user_chunk_cache_max 0 (unlimited) 128
+ png_user_chunk_malloc_max 0 (unlimited) 8,000,000
+
+B. Changes to the build and configuration of libpng
+
+Details of internal changes to the library code can be found in the CHANGES
+file and in the GIT repository logs. These will be of no concern to the vast
+majority of library users or builders; however, the few who configure libpng
+to a non-default feature set may need to change how this is done.
+
+There should be no need for library builders to alter build scripts if
+these use the distributed build support - configure or the makefiles -
+however, users of the makefiles may care to update their build scripts
+to build pnglibconf.h where the corresponding makefile does not do so.
+
+Building libpng with a non-default configuration has changed completely.
+The old method using pngusr.h should still work correctly even though the
+way pngusr.h is used in the build has been changed; however, library
+builders will probably want to examine the changes to take advantage of
+new capabilities and to simplify their build system.
+
+B.1 Specific changes to library configuration capabilities
+
+The library now supports a complete fixed point implementation and can
+thus be used on systems that have no floating point support or very
+limited or slow support. Previously gamma correction, an essential part
+of complete PNG support, required reasonably fast floating point.
+
+As part of this the choice of internal implementation has been made
+independent of the choice of fixed versus floating point APIs and all the
+missing fixed point APIs have been implemented.
+
+The exact mechanism used to control attributes of API functions has
+changed. A single set of operating system independent macro definitions
+is used and operating system specific directives are defined in
+pnglibconf.h
+
+As part of this the mechanism used to choose procedure call standards on
+those systems that allow a choice has been changed. At present this only
+affects certain Microsoft (DOS, Windows) and IBM (OS/2) operating systems
+running on Intel processors. As before, PNGAPI is defined where required
+to control the exported API functions; however, two new macros, PNGCBAPI
+and PNGCAPI, are used instead for callback functions (PNGCBAPI) and
+(PNGCAPI) for functions that must match a C library prototype (currently
+only png_longjmp_ptr, which must match the C longjmp function.) The new
+approach is documented in pngconf.h
+
+Despite these changes, libpng 1.5.0 only supports the native C function
+calling standard on those platforms tested so far (__cdecl on Microsoft
+Windows). This is because the support requirements for alternative
+calling conventions seem to no longer exist. Developers who find it
+necessary to set PNG_API_RULE to 1 should advise the mailing list
+(png-mng-implement) of this and library builders who use Openwatcom and
+therefore set PNG_API_RULE to 2 should also contact the mailing list.
+
+A new test program, pngvalid, is provided in addition to pngtest.
+pngvalid validates the arithmetic accuracy of the gamma correction
+calculations and includes a number of validations of the file format.
+A subset of the full range of tests is run when "make check" is done
+(in the 'configure' build.) pngvalid also allows total allocated memory
+usage to be evaluated and performs additional memory overwrite validation.
+
+Many changes to individual feature macros have been made. The following
+are the changes most likely to be noticed by library builders who
+configure libpng:
+
+1) All feature macros now have consistent naming:
+
+#define PNG_NO_feature turns the feature off
+#define PNG_feature_SUPPORTED turns the feature on
+
+pnglibconf.h contains one line for each feature macro which is either:
+
+#define PNG_feature_SUPPORTED
+
+if the feature is supported or:
+
+/*#undef PNG_feature_SUPPORTED*/
+
+if it is not. Library code consistently checks for the 'SUPPORTED' macro.
+It does not, and libpng applications should not, check for the 'NO' macro
+which will not normally be defined even if the feature is not supported.
+The 'NO' macros are only used internally for setting or not setting the
+corresponding 'SUPPORTED' macros.
+
+Compatibility with the old names is provided as follows:
+
+PNG_INCH_CONVERSIONS turns on PNG_INCH_CONVERSIONS_SUPPORTED
+
+And the following definitions disable the corresponding feature:
+
+PNG_SETJMP_NOT_SUPPORTED disables SETJMP
+PNG_READ_TRANSFORMS_NOT_SUPPORTED disables READ_TRANSFORMS
+PNG_NO_READ_COMPOSITED_NODIV disables READ_COMPOSITE_NODIV
+PNG_WRITE_TRANSFORMS_NOT_SUPPORTED disables WRITE_TRANSFORMS
+PNG_READ_ANCILLARY_CHUNKS_NOT_SUPPORTED disables READ_ANCILLARY_CHUNKS
+PNG_WRITE_ANCILLARY_CHUNKS_NOT_SUPPORTED disables WRITE_ANCILLARY_CHUNKS
+
+Library builders should remove use of the above, inconsistent, names.
+
+2) Warning and error message formatting was previously conditional on
+the STDIO feature. The library has been changed to use the
+CONSOLE_IO feature instead. This means that if CONSOLE_IO is disabled
+the library no longer uses the printf(3) functions, even though the
+default read/write implementations use (FILE) style stdio.h functions.
+
+3) Three feature macros now control the fixed/floating point decisions:
+
+PNG_FLOATING_POINT_SUPPORTED enables the floating point APIs
+
+PNG_FIXED_POINT_SUPPORTED enables the fixed point APIs; however, in
+practice these are normally required internally anyway (because the PNG
+file format is fixed point), therefore in most cases PNG_NO_FIXED_POINT
+merely stops the function from being exported.
+
+PNG_FLOATING_ARITHMETIC_SUPPORTED chooses between the internal floating
+point implementation or the fixed point one. Typically the fixed point
+implementation is larger and slower than the floating point implementation
+on a system that supports floating point; however, it may be faster on a
+system which lacks floating point hardware and therefore uses a software
+emulation.
+
+4) 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 buildtime whether or not to use macros (previously
+impossible because the functions weren't in the default build.)
+
+B.2 Changes to the configuration mechanism
+
+Prior to libpng-1.5.0 library builders who needed to configure libpng
+had either to modify the exported pngconf.h header file to add system
+specific configuration or had to write feature selection macros into
+pngusr.h and cause this to be included into pngconf.h by defining
+PNG_USER_CONFIG. The latter mechanism had the disadvantage that an
+application built without PNG_USER_CONFIG defined would see the
+unmodified, default, libpng API and thus would probably fail to link.
+
+These mechanisms still work in the configure build and in any makefile
+build that builds pnglibconf.h, although the feature selection macros
+have changed somewhat as described above. In 1.5.0, however, pngusr.h is
+processed only once, when the exported header file pnglibconf.h is built.
+pngconf.h no longer includes pngusr.h, therefore pngusr.h is ignored after the
+build of pnglibconf.h and it is never included in an application build.
+
+The rarely used alternative of adding a list of feature macros to the
+CFLAGS setting in the build also still works; however, the macros will be
+copied to pnglibconf.h and this may produce macro redefinition warnings
+when the individual C files are compiled.
+
+All configuration now only works if pnglibconf.h is built from
+scripts/pnglibconf.dfa. This requires the program awk. Brian Kernighan
+(the original author of awk) maintains C source code of that awk and this
+and all known later implementations (often called by subtly different
+names - nawk and gawk for example) are adequate to build pnglibconf.h.
+The Sun Microsystems (now Oracle) program 'awk' is an earlier version
+and does not work; this may also apply to other systems that have a
+functioning awk called 'nawk'.
+
+Configuration options are now documented in scripts/pnglibconf.dfa. This
+file also includes dependency information that ensures a configuration is
+consistent; that is, if a feature is switched off dependent features are
+also removed. As a recommended alternative to using feature macros in
+pngusr.h a system builder may also define equivalent options in pngusr.dfa
+(or, indeed, any file) and add that to the configuration by setting
+DFA_XTRA to the file name. The makefiles in contrib/pngminim illustrate
+how to do this, and a case where pngusr.h is still required.
+
+XI. Detecting libpng
The png_get_io_ptr() function has been present since libpng-0.88, has never
changed, and is unaffected by conditional compilation macros. It is the
@@ -3168,7 +4474,7 @@ libpng version since 0.88. In an autoconf "configure.in" you could use AC_CHECK_LIB(png, png_get_io_ptr, ...
-XI. Source code repository
+XII. Source code repository
Since about February 2009, version 1.2.34, libpng has been under "git" source
control. The git repository was built from old libpng-x.y.z.tar.gz files
@@ -3187,7 +4493,12 @@ the libpng bug tracker at http://libpng.sourceforge.net
-XII. Coding style
+We also accept patches built from the tar or zip distributions, and
+simple verbal discriptions of bug fixes, reported either to the
+SourceForge bug tracker, to the png-mng-implement at lists.sf.net
+mailing list, or directly to glennrp.
+
+XIII. Coding style
Our coding style is similar to the "Allman" style, with curly
braces on separate lines:
@@ -3244,7 +4555,7 @@ Functions and their curly braces are not indented, and exported functions are marked with PNGAPI:
/* This is a public function that is visible to
- * application programers. It does thus-and-so.
+ * application programmers. It does thus-and-so.
*/
void PNGAPI
png_exported_function(png_ptr, png_info, foo)
@@ -3272,12 +4583,13 @@ above the comment that says /* Maintainer: Put new private prototypes here ^ and in libpngpf.3 */
-The names of all exported functions and variables begin
-with "png_", and all publicly visible C preprocessor
-macros begin with "PNG_".
+To avoid polluting the global namespace, the names of all exported
+functions and variables begin with "png_", and all publicly visible C
+preprocessor macros begin with "PNG". We request that applications that
+use libpng *not* begin any of their own symbols with either of these strings.
We put a space after each comma and after each semicolon
-in "for" statments, and we put spaces before and after each
+in "for" statements, and we put spaces before and after each
C binary operator and after "for" or "while", and before
"?". We don't put a space between a typecast and the expression
being cast, nor do we put one between a function name and the
@@ -3289,33 +4601,36 @@ left parenthesis that follows it: We prefer #ifdef and #ifndef to #if defined() and if !defined()
when there is only one macro being tested.
+We prefer to express integers that are used as bit masks in hex format,
+with an even number of lower-case hex digits (e.g., 0x00, 0xff, 0x0100).
+
We do not use the TAB character for indentation in the C sources.
Lines do not exceed 80 characters.
Other rules can be inferred by inspecting the libpng source.
-XIII. Y2K Compliance in libpng
+XIV. Y2K Compliance in libpng
-June 26, 2010
+September 27, 2012
Since the PNG Development group is an ad-hoc body, we can't make
an official declaration.
This is your unofficial assurance that libpng from version 0.71 and
-upward through 1.4.3 are Y2K compliant. It is my belief that earlier
+upward through 1.5.13 are Y2K compliant. It is my belief that earlier
versions were also Y2K compliant.
-Libpng only has three year fields. One is a 2-byte unsigned integer that
-will hold years up to 65535. The other two hold the date in text
+Libpng only has two year fields. One is a 2-byte unsigned integer that
+will hold years up to 65535. The other holds the date in text
format, and will hold years up to 9999.
The integer is
"png_uint_16 year" in png_time_struct.
-The strings are
- "png_charp time_buffer" in png_struct and
- "near_time_buffer", which is a local character string in png.c.
+The string is
+ "char time_buffer[29]" in png_struct. This will no
+longer be used in libpng-1.6.x and will be removed from libpng-1.7.0.
There are seven time-related functions:
diff --git a/plugins/AdvaImg/src/LibPNG/libpng.3 b/plugins/AdvaImg/src/LibPNG/libpng.3 index 1d72ab4cae..e0e0aec725 100644 --- a/plugins/AdvaImg/src/LibPNG/libpng.3 +++ b/plugins/AdvaImg/src/LibPNG/libpng.3 @@ -1,6 +1,6 @@ -.TH LIBPNG 3 "February 18, 2012"
+.TH LIBPNG 3 "September 27, 2012"
.SH NAME
-libpng \- Portable Network Graphics (PNG) Reference Library 1.5.9
+libpng \- Portable Network Graphics (PNG) Reference Library 1.5.13
.SH SYNOPSIS
\fI\fB
@@ -552,6 +552,10 @@ libpng \- Portable Network Graphics (PNG) Reference Library 1.5.9 \fI\fB
+\fBvoid png_set_check_for_invalid_index(png_structrp \fP\fIpng_ptr\fP\fB, int \fIallowed\fP\fB);\fP
+
+\fI\fB
+
\fBvoid png_set_cHRM (png_structp \fP\fIpng_ptr\fP\fB, png_infop \fP\fIinfo_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
\fI\fB
@@ -958,14 +962,6 @@ libpng \- Portable Network Graphics (PNG) Reference Library 1.5.9 \fI\fB
-\fBvoidpf png_zalloc (voidpf \fP\fIpng_ptr\fP\fB, uInt \fP\fIitems\fP\fB, uInt \fIsize\fP\fB);\fP
-
-\fI\fB
-
-\fBvoid png_zfree (voidpf \fP\fIpng_ptr\fP\fB, voidpf \fIptr\fP\fB);\fP
-
-\fI\fB
-
.SH DESCRIPTION
The
.I libpng
@@ -975,12 +971,12 @@ the Portable Network Graphics (PNG) format image files. It uses the compression library.
Following is a copy of the libpng-manual.txt file that accompanies libpng.
.SH LIBPNG.TXT
-libpng-manual.txt - A description on how to use and modify libpng
+Libpng-manual.txt - A description on how to use and modify libpng
- libpng version 1.5.9 - February 18, 2012
+ libpng version 1.5.13 - September 27, 2012
Updated and distributed by Glenn Randers-Pehrson
<glennrp at users.sourceforge.net>
- Copyright (c) 1998-2011 Glenn Randers-Pehrson
+ Copyright (c) 1998-2012 Glenn Randers-Pehrson
This document is released under the libpng license.
For conditions of distribution and use, see the disclaimer
@@ -988,9 +984,9 @@ libpng-manual.txt - A description on how to use and modify libpng Based on:
- libpng versions 0.97, January 1998, through 1.5.9 - February 18, 2012
+ libpng versions 0.97, January 1998, through 1.5.13 - September 27, 2012
Updated and distributed by Glenn Randers-Pehrson
- Copyright (c) 1998-2011 Glenn Randers-Pehrson
+ Copyright (c) 1998-2012 Glenn Randers-Pehrson
libpng 1.0 beta 6 version 0.96 May 28, 1997
Updated and distributed by Andreas Dilger
@@ -1118,8 +1114,8 @@ APIs. Most of these are fairly obvious; for example types corresponding to integers of particular sizes and types for passing color values.
One exception is how non-integral numbers are handled. For application
-convenience most APIs that take such numbers have C (double) arguments,
-however internally PNG, and libpng, use 32 bit signed integers and encode
+convenience most APIs that take such numbers have C (double) arguments;
+however, internally PNG, and libpng, use 32 bit signed integers and encode
the value by multiplying by 100,000. As of libpng 1.5.0 a convenience
macro PNG_FP_1 is defined in png.h along with a type (png_fixed_point)
which is simply (png_int_32).
@@ -1700,11 +1696,11 @@ Libpng only supports composing onto a single color (using png_set_background; see below). Otherwise you must do the composition yourself and, in this case,
you may need to call png_set_alpha_mode:
-#if PNG_LIBPNG_VER >= 10504
- png_set_alpha_mode(png_ptr, mode, screen_gamma);
-#else
- png_set_gamma(png_ptr, screen_gamma, 1.0/screen_gamma);
-#endif
+ #if PNG_LIBPNG_VER >= 10504
+ png_set_alpha_mode(png_ptr, mode, screen_gamma);
+ #else
+ png_set_gamma(png_ptr, screen_gamma, 1.0/screen_gamma);
+ #endif
The screen_gamma value is the same as the argument to png_set_gamma; however,
how it affects the output depends on the mode. png_set_alpha_mode() sets the
@@ -1776,7 +1772,7 @@ the screen_gamma value. Pixels with alpha less than 1.0 will still have linear components.
Use this format if you have control over your
-compositing software and do don't do other arithmetic
+compositing software and so don't do other arithmetic
(such as scaling) on the data you get from libpng. Your
compositing software can simply copy opaque pixels to
the output but still has linear values for the
@@ -2107,6 +2103,11 @@ data has been read, or zero if it is missing. The parameters to the png_get_<chunk> are set directly if they are simple data types, or a
pointer into the info_ptr is returned for any complex types.
+The colorspace data from gAMA, cHRM, sRGB, iCCP, and sBIT chunks
+is simply returned to give the application information about how the
+image was encoded. Libpng itself only does transformations using the file
+gamma when combining semitransparent pixels with the background color.
+
png_get_PLTE(png_ptr, info_ptr, &palette,
&num_palette);
@@ -2118,14 +2119,14 @@ pointer into the info_ptr is returned for any complex types. png_get_gAMA(png_ptr, info_ptr, &file_gamma);
png_get_gAMA_fixed(png_ptr, info_ptr, &int_file_gamma);
- file_gamma - the gamma at which the file is
+ file_gamma - the gamma at which the file was
written (PNG_INFO_gAMA)
int_file_gamma - 100,000 times the gamma at which the
file is written
- png_get_cHRM(png_ptr, info_ptr, &white_x, &white_y, &red_x, &red_y,
- &green_x, &green_y, &blue_x, &blue_y)
+ png_get_cHRM(png_ptr, info_ptr, &white_x, &white_y, &red_x,
+ &red_y, &green_x, &green_y, &blue_x, &blue_y)
png_get_cHRM_XYZ(png_ptr, info_ptr, &red_X, &red_Y, &red_Z, &green_X,
&green_Y, &green_Z, &blue_X, &blue_Y, &blue_Z)
png_get_cHRM_fixed(png_ptr, info_ptr, &int_white_x, &int_white_y,
@@ -2136,8 +2137,9 @@ pointer into the info_ptr is returned for any complex types. &int_blue_X, &int_blue_Y, &int_blue_Z)
{white,red,green,blue}_{x,y}
- A color space encoding specified using the chromaticities
- of the end points and the white point. (PNG_INFO_cHRM)
+ A color space encoding specified using the
+ chromaticities of the end points and the
+ white point. (PNG_INFO_cHRM)
{red,green,blue}_{X,Y,Z}
A color space encoding specified using the encoding end
@@ -2548,17 +2550,19 @@ Within the matrix, "A" means the transformation is obtained by png_set_add_alpha().
"X" means the transformation is obtained by png_set_expand().
"1" means the transformation is obtained by
- png_set_expand_gray_1_2_4_to_8() (and by png_set_expand() if there
- is no transparency in the original or the final format).
+ png_set_expand_gray_1_2_4_to_8() (and by png_set_expand()
+ if there is no transparency in the original or the final
+ format).
"C" means the transformation is obtained by png_set_gray_to_rgb().
"G" means the transformation is obtained by png_set_rgb_to_gray().
"P" means the transformation is obtained by
png_set_expand_palette_to_rgb().
"p" means the transformation is obtained by png_set_packing().
"Q" means the transformation is obtained by png_set_quantize().
- "T" means the transformation is obtained by png_set_tRNS_to_alpha().
- "B" means the transformation is obtained by png_set_background(), or
- png_strip_alpha().
+ "T" means the transformation is obtained by
+ png_set_tRNS_to_alpha().
+ "B" means the transformation is obtained by
+ png_set_background(), or png_strip_alpha().
When an entry has multiple transforms listed all are required to cause the
right overall transformation. When two transforms are separated by a comma
@@ -2643,8 +2647,8 @@ with alpha. if (color_type == PNG_COLOR_TYPE_RGB ||
color_type == PNG_COLOR_TYPE_RGB_ALPHA)
- png_set_rgb_to_gray(png_ptr, error_action, double red_weight,
- double green_weight);
+ png_set_rgb_to_gray(png_ptr, error_action,
+ double red_weight, double green_weight);
error_action = 1: silently do the conversion
@@ -2666,7 +2670,8 @@ with alpha. In the corresponding fixed point API the red_weight and green_weight values are
simply scaled by 100,000:
- png_set_rgb_to_gray(png_ptr, error_action, png_fixed_point red_weight,
+ png_set_rgb_to_gray(png_ptr, error_action,
+ png_fixed_point red_weight,
png_fixed_point green_weight);
If you have set error_action = 1 or 2, you can
@@ -2710,7 +2715,7 @@ the current display (e.g., the background color from a web page). You need to tell libpng how the color is represented, both the format of the
component values in the color (the number of bits) and the gamma encoding of the
color. The function takes two arguments, background_gamma_mode and need_expand
-to convey this information, however only two combinations are likely to be
+to convey this information; however, only two combinations are likely to be
useful:
png_color_16 my_background;
@@ -3004,7 +3009,7 @@ the second parameter NULL. If you don't want libpng to handle the interlacing details, just call
png_read_rows() PNG_INTERLACE_ADAM7_PASSES times to read in all the images.
-Each of the images is a valid image by itself, however you will almost
+Each of the images is a valid image by itself; however, you will almost
certainly need to distribute the pixels from each sub-image to the
correct place. This is where everything gets very tricky.
@@ -3161,7 +3166,7 @@ sPLT, only the n'th item in the structure is freed, where n is "seq". The default behavior is only to free data that was allocated internally
by libpng. This can be changed, so that libpng will not free the data,
or so that it will free data that was allocated by the user with png_malloc()
-or png_zalloc() and passed in via a png_set_*() function, with
+or png_calloc() and passed in via a png_set_*() function, with
png_data_freer(png_ptr, info_ptr, freer, mask)
@@ -3182,7 +3187,7 @@ or png_destroy_*() is supposed to free the data. When the user assumes responsibility for libpng-allocated data, the application must use
png_free() to free it, and when the user transfers responsibility to libpng
for data that the user has allocated, the user must have used png_malloc()
-or png_zalloc() to allocate it.
+or png_calloc() to allocate it.
If you allocated your row_pointers in a single block, as suggested above in
the description of the high level read interface, you must not transfer
@@ -4000,8 +4005,8 @@ tEXt chunk use RFC 1123 format dates (e.g. "22 May 1997 18:07:10 GMT"), although this isn't a requirement. Unlike the tIME chunk, the
"Creation Time" tEXt chunk is not expected to be automatically changed
by the software. To facilitate the use of RFC 1123 dates, a function
-png_convert_to_rfc1123(png_timep) is provided to convert from PNG
-time to an RFC 1123 format string.
+png_convert_to_rfc1123(png_ptr, png_timep) is provided to convert
+from PNG time to an RFC 1123 format string.
.SS Writing unknown chunks
@@ -4363,7 +4368,7 @@ png_destroy_write_struct(). The default behavior is only to free data that was allocated internally
by libpng. This can be changed, so that libpng will not free the data,
or so that it will free data that was allocated by the user with png_malloc()
-or png_zalloc() and passed in via a png_set_*() function, with
+or png_calloc() and passed in via a png_set_*() function, with
png_data_freer(png_ptr, info_ptr, freer, mask)
@@ -4399,7 +4404,7 @@ When the user assumes responsibility for libpng-allocated data, the application must use
png_free() to free it, and when the user transfers responsibility to libpng
for data that the user has allocated, the user must have used png_malloc()
-or png_zalloc() to allocate it.
+or png_calloc() to allocate it.
If you allocated text_ptr.text, text_ptr.lang, and text_ptr.translated_keyword
separately, do not transfer responsibility for freeing text_ptr to libpng,
@@ -4427,12 +4432,13 @@ in pngmem.c, pngrio.c, pngwio.c, and pngerror.c, respectively. To change these functions, call the appropriate png_set_*_fn() function.
Memory allocation is done through the functions png_malloc(), png_calloc(),
-and png_free(). These currently just call the standard C functions.
-png_calloc() calls png_malloc() and then clears the newly
-allocated memory to zero. There is limited support for certain systems
-with segmented memory architectures and the types of pointers declared by
-png.h match this; you will have to use appropriate pointers in your
-application. Since it is
+and png_free(). The png_malloc() and png_free() functions currently just
+call the standard C functions and png_calloc() calls png_malloc() and then
+clears the newly allocated memory to zero; note that png_calloc(png_ptr, size)
+is not the same as the calloc(number, size) function provided by stdlib.h.
+There is limited support for certain systems with segmented memory
+architectures and the types of pointers declared by png.h match this; you
+will have to use appropriate pointers in your application. Since it is
unlikely that the method of handling memory allocation on a platform
will change between applications, these functions must be modified in
the library at compile time. If you prefer to use a different method
@@ -4663,7 +4669,7 @@ available to set these separately for non-IDAT compressed chunks such as zTXt, iTXt, and iCCP:
#include zlib.h
- #if PNG_LIBPNG_VER <= 10504
+ #if PNG_LIBPNG_VER >= 10504
png_set_text_compression_level(png_ptr, level);
png_set_text_compression_mem_level(png_ptr, level);
@@ -5062,8 +5068,8 @@ png_get_mmx_bitdepth_threshold(), png_get_mmx_rowbytes_threshold(), png_set_asm_flags(), and png_mmx_supported()
We removed the obsolete png_check_sig(), png_memcpy_check(), and
-png_memset_check() functions. Instead use !png_sig_cmp(), memcpy(),
-and memset(), respectively.
+png_memset_check() functions. Instead use !png_sig_cmp(), png_memcpy(),
+and png_memset(), respectively.
The function png_set_gray_1_2_4_to_8() was removed. It has been
deprecated since libpng-1.0.18 and 1.2.9, when it was replaced with
@@ -5100,7 +5106,9 @@ png_set_strip_error_numbers() was removed from the library by default. The png_zalloc() and png_zfree() functions are no longer exported.
The png_zalloc() function no longer zeroes out the memory that it
-allocates.
+allocates. Applications that called png_zalloc(png_ptr, number, size)
+can call png_calloc(png_ptr, number*size) instead, and can call
+png_free() instead of png_zfree().
Support for dithering was disabled by default in libpng-1.4.0, because
it has not been well tested and doesn't actually "dither".
@@ -5120,12 +5128,22 @@ We removed the trailing '.' from the warning and error messages. From libpng-1.4.0 until 1.4.4, the png_get_uint_16 macro (but not the
function) incorrectly returned a value of type png_uint_32.
+Checking for invalid palette index on read or write was added at libpng
+1.5.10. When an invalid index is found, libpng issues a benign error.
+This is enabled by default but can be disabled in each png_ptr with
+
+ png_set_check_for_invalid_index(png_ptr, allowed);
+
+ allowed - one of
+ 0: disable
+ 1: enable
+
A. Changes that affect users of libpng
There are no substantial API changes between the non-deprecated parts of
-the 1.4.5 API and the 1.5.0 API, however the ability to directly access
-the main libpng control structures, png_struct and png_info, deprecated
-in earlier versions of libpng, has been completely removed from
+the 1.4.5 API and the 1.5.0 API; however, the ability to directly access
+members of the main libpng control structures, png_struct and png_info,
+deprecated in earlier versions of libpng, has been completely removed from
libpng 1.5.
We no longer include zlib.h in png.h. Applications that need access
@@ -5133,9 +5151,12 @@ to information in zlib.h will need to add the '#include "zlib.h"' directive. It does not matter whether it is placed prior to or after
the '"#include png.h"' directive.
-We moved the png_strcpy(), png_strncpy(), png_strlen(), png_memcpy(),
-png_memcmp(), png_sprintf, and png_memcpy() macros into a private
-header file (pngpriv.h) that is not accessible to applications.
+The png_sprintf(), png_strcpy(), and png_strncpy() macros are no longer used
+and were removed.
+
+We moved the png_strlen(), png_memcpy(), png_memset(), and png_memcmp()
+macros into a private header file (pngpriv.h) that is not accessible to
+applications.
In png_get_iCCP, the type of "profile" was changed from png_charpp
to png_bytepp, and in png_set_iCCP, from png_charp to png_const_bytep.
@@ -5238,16 +5259,30 @@ PNG_USER_WIDTH_MAX and PNG_USER_HEIGHT_MAX, although this document said that it could be used to override them. Now this function will reduce or
increase the limits.
+Starting in libpng-1.5.10, the user limits can be set en masse with the
+configuration option PNG_SAFE_LIMITS_SUPPORTED. If this option is enabled,
+a set of "safe" limits is applied in pngpriv.h. These can be overridden by
+application calls to png_set_user_limits(), png_set_user_chunk_cache_max(),
+and/or png_set_user_malloc_max() that increase or decrease the limits. Also,
+in libpng-1.5.10 the default width and height limits were increased
+from 1,000,000 to 0x7ffffff (i.e., made unlimited). Therefore, the
+limits are now
+ default safe
+ png_user_width_max 0x7fffffff 1,000,000
+ png_user_height_max 0x7fffffff 1,000,000
+ png_user_chunk_cache_max 0 (unlimited) 128
+ png_user_chunk_malloc_max 0 (unlimited) 8,000,000
+
B. Changes to the build and configuration of libpng
Details of internal changes to the library code can be found in the CHANGES
file and in the GIT repository logs. These will be of no concern to the vast
-majority of library users or builders, however the few who configure libpng
+majority of library users or builders; however, the few who configure libpng
to a non-default feature set may need to change how this is done.
There should be no need for library builders to alter build scripts if
these use the distributed build support - configure or the makefiles -
-however users of the makefiles may care to update their build scripts
+however, users of the makefiles may care to update their build scripts
to build pnglibconf.h where the corresponding makefile does not do so.
Building libpng with a non-default configuration has changed completely.
@@ -5353,7 +5388,7 @@ merely stops the function from being exported. PNG_FLOATING_ARITHMETIC_SUPPORTED chooses between the internal floating
point implementation or the fixed point one. Typically the fixed point
implementation is larger and slower than the floating point implementation
-on a system that supports floating point, however it may be faster on a
+on a system that supports floating point; however, it may be faster on a
system which lacks floating point hardware and therefore uses a software
emulation.
@@ -5382,7 +5417,7 @@ pngconf.h no longer includes pngusr.h, therefore pngusr.h is ignored after the build of pnglibconf.h and it is never included in an application build.
The rarely used alternative of adding a list of feature macros to the
-CFLAGS setting in the build also still works, however the macros will be
+CFLAGS setting in the build also still works; however, the macros will be
copied to pnglibconf.h and this may produce macro redefinition warnings
when the individual C files are compiled.
@@ -5523,8 +5558,8 @@ above the comment that says /* Maintainer: Put new private prototypes here ^ and in libpngpf.3 */
To avoid polluting the global namespace, the names of all exported
-functions and variables begin with "png_", and all publicly visible C
-preprocessor macros begin with "PNG_". We request that applications that
+functions and variables begin with "png_", and all publicly visible C
+preprocessor macros begin with "PNG". We request that applications that
use libpng *not* begin any of their own symbols with either of these strings.
We put a space after each comma and after each semicolon
@@ -5551,25 +5586,25 @@ Other rules can be inferred by inspecting the libpng source. .SH XIV. Y2K Compliance in libpng
-February 18, 2012
+September 27, 2012
Since the PNG Development group is an ad-hoc body, we can't make
an official declaration.
This is your unofficial assurance that libpng from version 0.71 and
-upward through 1.5.9 are Y2K compliant. It is my belief that earlier
+upward through 1.5.13 are Y2K compliant. It is my belief that earlier
versions were also Y2K compliant.
-Libpng only has three year fields. One is a 2-byte unsigned integer that
-will hold years up to 65535. The other two hold the date in text
+Libpng only has two year fields. One is a 2-byte unsigned integer that
+will hold years up to 65535. The other holds the date in text
format, and will hold years up to 9999.
The integer is
"png_uint_16 year" in png_time_struct.
-The strings are
- "png_charp time_buffer" in png_struct and
- "near_time_buffer", which is a local character string in png.c.
+The string is
+ "char time_buffer[29]" in png_struct. This will no
+longer be used in libpng-1.6.x and will be removed from libpng-1.7.0.
There are seven time-related functions:
@@ -5768,6 +5803,15 @@ the first widely used release: 1.5.9beta01-02 15 10509 15.so.15.9[.0]
1.5.9rc01 15 10509 15.so.15.9[.0]
1.5.9 15 10509 15.so.15.9[.0]
+ 1.5.10beta01-05 15 10510 15.so.15.10[.0]
+ 1.5.10 15 10510 15.so.15.10[.0]
+ 1.5.11beta01 15 10511 15.so.15.11[.0]
+ 1.5.11rc01-05 15 10511 15.so.15.11[.0]
+ 1.5.11 15 10511 15.so.15.11[.0]
+ 1.5.12 15 10512 15.so.15.12[.0]
+ 1.5.13beta01-02 15 10513 15.so.15.13[.0]
+ 1.5.13rc01 15 10513 15.so.15.13[.0]
+ 1.5.13 15 10513 15.so.15.13[.0]
Henceforth the source version will match the shared-library minor
and patch numbers; the shared-library major version number will be
@@ -5824,7 +5868,7 @@ possible without all of you. Thanks to Frank J. T. Wojcik for helping with the documentation.
-Libpng version 1.5.9 - February 18, 2012:
+Libpng version 1.5.13 - September 27, 2012:
Initially created in 1995 by Guy Eric Schalnat, then of Group 42, Inc.
Currently maintained by Glenn Randers-Pehrson (glennrp at users.sourceforge.net).
@@ -5847,7 +5891,7 @@ this sentence. This code is released under the libpng license.
-libpng versions 1.2.6, August 15, 2004, through 1.5.9, February 18, 2012, are
+libpng versions 1.2.6, August 15, 2004, through 1.5.13, September 27, 2012, are
Copyright (c) 2004,2006-2007 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
@@ -5946,7 +5990,7 @@ certification mark of the Open Source Initiative. Glenn Randers-Pehrson
glennrp at users.sourceforge.net
-February 18, 2012
+September 27, 2012
.\" end of man page
diff --git a/plugins/AdvaImg/src/LibPNG/libpngpf.3 b/plugins/AdvaImg/src/LibPNG/libpngpf.3 index ef54f7b5b0..f6b62a0323 100644 --- a/plugins/AdvaImg/src/LibPNG/libpngpf.3 +++ b/plugins/AdvaImg/src/LibPNG/libpngpf.3 @@ -1,6 +1,6 @@ -.TH LIBPNGPF 3 "February 18, 2012"
+.TH LIBPNGPF 3 "September 27, 2012"
.SH NAME
-libpng \- Portable Network Graphics (PNG) Reference Library 1.5.9
+libpng \- Portable Network Graphics (PNG) Reference Library 1.5.13
(private functions)
.SH SYNOPSIS
\fB#include \fI"pngpriv.h"
diff --git a/plugins/AdvaImg/src/LibPNG/png.5 b/plugins/AdvaImg/src/LibPNG/png.5 index 6df917d4ae..cfd109f291 100644 --- a/plugins/AdvaImg/src/LibPNG/png.5 +++ b/plugins/AdvaImg/src/LibPNG/png.5 @@ -1,4 +1,4 @@ -.TH PNG 5 "February 18, 2012"
+.TH PNG 5 "September 27, 2012"
.SH NAME
png \- Portable Network Graphics (PNG) format
.SH DESCRIPTION
diff --git a/plugins/AdvaImg/src/LibPNG/png.c b/plugins/AdvaImg/src/LibPNG/png.c index 0df53a62af..55fbc8fcc1 100644 --- a/plugins/AdvaImg/src/LibPNG/png.c +++ b/plugins/AdvaImg/src/LibPNG/png.c @@ -1,8 +1,8 @@ /* png.c - location for general purpose libpng functions
*
- * Last changed in libpng 1.5.7 [December 15, 2011]
- * Copyright (c) 1998-2011 Glenn Randers-Pehrson
+ * Last changed in libpng 1.5.11 [June 14, 2012]
+ * Copyright (c) 1998-2012 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_9 Your_png_h_is_not_version_1_5_9;
+typedef png_libpng_version_1_5_13 Your_png_h_is_not_version_1_5_13;
/* 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
@@ -655,14 +655,14 @@ png_get_copyright(png_const_structp png_ptr) #else
# ifdef __STDC__
return PNG_STRING_NEWLINE \
- "libpng version 1.5.9 - February 18, 2012" PNG_STRING_NEWLINE \
- "Copyright (c) 1998-2011 Glenn Randers-Pehrson" PNG_STRING_NEWLINE \
+ "libpng version 1.5.13 - September 27, 2012" PNG_STRING_NEWLINE \
+ "Copyright (c) 1998-2012 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 1.5.9 - February 18, 2012\
- Copyright (c) 1998-2011 Glenn Randers-Pehrson\
+ return "libpng version 1.5.13 - September 27, 2012\
+ Copyright (c) 1998-2012 Glenn Randers-Pehrson\
Copyright (c) 1996-1997 Andreas Dilger\
Copyright (c) 1995-1996 Guy Eric Schalnat, Group 42, Inc.";
# endif
@@ -969,8 +969,8 @@ int png_XYZ_from_xy(png_XYZ *XYZ, png_xy xy) * and it is certain that it becomes unstable where the end points are close
* together.
*
- * So this code uses the perhaps slighly less optimal but more understandable
- * and totally obvious approach of calculating color-scale.
+ * So this code uses the perhaps slightly less optimal but more
+ * understandable and totally obvious approach of calculating color-scale.
*
* This algorithm depends on the precision in white-scale and that is
* (1/white-y), so we can immediately see that as white-y approaches 0 the
@@ -1035,13 +1035,13 @@ int png_XYZ_from_xy(png_XYZ *XYZ, png_xy xy) *
* red-scale =
* ( (green-x - blue-x) * (white-y - blue-y) -
- * (green-y - blue-y) * (white-x - blue-x)) / white-y
+ * (green-y - blue-y) * (white-x - blue-x) ) / white-y
* -------------------------------------------------------------------------
* (green-x - blue-x)*(red-y - blue-y)-(green-y - blue-y)*(red-x - blue-x)
*
* green-scale =
* ( (red-y - blue-y) * (white-x - blue-x) -
- * (red-x - blue-x) * (white-y - blue-y)) / white-y
+ * (red-x - blue-x) * (white-y - blue-y) ) / white-y
* -------------------------------------------------------------------------
* (green-x - blue-x)*(red-y - blue-y)-(green-y - blue-y)*(red-x - blue-x)
*
@@ -1467,7 +1467,7 @@ static double png_pow10(int power)
{
int recip = 0;
- double d = 1;
+ double d = 1.0;
/* Handle negative exponent with a reciprocal at the end because
* 10 is exact whereas .1 is inexact in base 2
@@ -1481,7 +1481,7 @@ png_pow10(int power) if (power > 0)
{
/* Decompose power bitwise. */
- double mult = 10;
+ double mult = 10.0;
do
{
if (power & 1) d *= mult;
@@ -1600,7 +1600,8 @@ png_ascii_from_fp(png_structp png_ptr, png_charp ascii, png_size_t size, {
double d;
- fp *= 10;
+ fp *= 10.0;
+
/* Use modf here, not floor and subtract, so that
* the separation is done in one step. At the end
* of the loop don't break the number into parts so
@@ -1613,7 +1614,7 @@ png_ascii_from_fp(png_structp png_ptr, png_charp ascii, png_size_t size, {
d = floor(fp + .5);
- if (d > 9)
+ if (d > 9.0)
{
/* Rounding up to 10, handle that here. */
if (czero > 0)
@@ -1621,9 +1622,10 @@ png_ascii_from_fp(png_structp png_ptr, png_charp ascii, png_size_t size, --czero, d = 1;
if (cdigits == 0) --clead;
}
+
else
{
- while (cdigits > 0 && d > 9)
+ while (cdigits > 0 && d > 9.0)
{
int ch = *--ascii;
@@ -1648,7 +1650,7 @@ png_ascii_from_fp(png_structp png_ptr, png_charp ascii, png_size_t size, * exponent but take into account the leading
* decimal point.
*/
- if (d > 9) /* cdigits == 0 */
+ if (d > 9.0) /* cdigits == 0 */
{
if (exp_b10 == (-1))
{
@@ -1669,18 +1671,19 @@ png_ascii_from_fp(png_structp png_ptr, png_charp ascii, png_size_t size, ++exp_b10;
/* In all cases we output a '1' */
- d = 1;
+ d = 1.0;
}
}
}
fp = 0; /* Guarantees termination below. */
}
- if (d == 0)
+ if (d == 0.0)
{
++czero;
if (cdigits == 0) ++clead;
}
+
else
{
/* Included embedded zeros in the digit count. */
@@ -1708,6 +1711,7 @@ png_ascii_from_fp(png_structp png_ptr, png_charp ascii, png_size_t size, above */
--exp_b10;
}
+
*ascii++ = (char)(48 + (int)d), ++cdigits;
}
}
@@ -2040,7 +2044,7 @@ png_muldiv_warn(png_structp png_ptr, png_fixed_point a, png_int_32 times, }
#endif
-#ifdef PNG_READ_GAMMA_SUPPORTED /* more fixed point functions for gammma */
+#ifdef PNG_READ_GAMMA_SUPPORTED /* more fixed point functions for gamma */
/* Calculate a reciprocal, return 0 on div-by-zero or overflow. */
png_fixed_point
png_reciprocal(png_fixed_point a)
diff --git a/plugins/AdvaImg/src/LibPNG/png.h b/plugins/AdvaImg/src/LibPNG/png.h index 81267675a5..6d762fca69 100644 --- a/plugins/AdvaImg/src/LibPNG/png.h +++ b/plugins/AdvaImg/src/LibPNG/png.h @@ -1,7 +1,7 @@ /* png.h - header file for PNG reference library
*
- * libpng version 1.5.9 - February 18, 2012
+ * libpng version 1.5.13 - September 27, 2012
* Copyright (c) 1998-2012 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.)
@@ -11,7 +11,7 @@ * Authors and maintainers:
* libpng versions 0.71, May 1995, through 0.88, January 1996: Guy Schalnat
* libpng versions 0.89c, June 1996, through 0.96, May 1997: Andreas Dilger
- * libpng versions 0.97, January 1998, through 1.5.9 - February 18, 2012: Glenn
+ * libpng versions 0.97, January 1998, through 1.5.13 - September 27, 2012: Glenn
* See also "Contributing Authors", below.
*
* Note about libpng version numbers:
@@ -172,6 +172,15 @@ * 1.5.9beta01-02 15 10509 15.so.15.9[.0]
* 1.5.9rc01 15 10509 15.so.15.9[.0]
* 1.5.9 15 10509 15.so.15.9[.0]
+ * 1.5.10beta01-05 15 10510 15.so.15.10[.0]
+ * 1.5.10 15 10510 15.so.15.10[.0]
+ * 1.5.11beta01 15 10511 15.so.15.11[.0]
+ * 1.5.11rc01-05 15 10511 15.so.15.11[.0]
+ * 1.5.11 15 10511 15.so.15.11[.0]
+ * 1.5.12 15 10512 15.so.15.12[.0]
+ * 1.5.13beta01-02 15 10513 15.so.15.13[.0]
+ * 1.5.13rc01 15 10513 15.so.15.13[.0]
+ * 1.5.13 15 10513 15.so.15.13[.0]
*
* Henceforth the source version will match the shared-library major
* and minor numbers; the shared-library major version number will be
@@ -181,7 +190,7 @@ * to the source version x.y.z (leading zeros in y and z). Beta versions
* were given the previous public release number plus a letter, until
* version 1.0.6j; from then on they were given the upcoming public
- * release number plus "betaNN" or "rcN".
+ * release number plus "betaNN" or "rcNN".
*
* Binary incompatibility exists only when applications make direct access
* to the info_ptr or png_ptr members through png.h, and the compiled
@@ -203,7 +212,7 @@ *
* This code is released under the libpng license.
*
- * libpng versions 1.2.6, August 15, 2004, through 1.5.9, February 18, 2012, are
+ * libpng versions 1.2.6, August 15, 2004, through 1.5.13, September 27, 2012, are
* Copyright (c) 2004, 2006-2012 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:
@@ -315,13 +324,13 @@ * Y2K compliance in libpng:
* =========================
*
- * February 18, 2012
+ * September 27, 2012
*
* Since the PNG Development group is an ad-hoc body, we can't make
* an official declaration.
*
* This is your unofficial assurance that libpng from version 0.71 and
- * upward through 1.5.9 are Y2K compliant. It is my belief that
+ * upward through 1.5.13 are Y2K compliant. It is my belief that
* earlier versions were also Y2K compliant.
*
* Libpng only has two year fields. One is a 2-byte unsigned integer
@@ -332,7 +341,8 @@ * "png_uint_16 year" in png_time_struct.
*
* The string is
- * "png_char time_buffer" in png_struct
+ * "char time_buffer[29]" in png_struct. This will be no
+ * longer used in libpng-1.6.0 and will be removed from libpng-1.7.0.
*
* There are seven time-related functions:
* png.c: png_convert_to_rfc_1123() in png.c
@@ -379,9 +389,9 @@ */
/* Version information for png.h - this should match the version in png.c */
-#define PNG_LIBPNG_VER_STRING "1.5.9"
+#define PNG_LIBPNG_VER_STRING "1.5.13"
#define PNG_HEADER_VERSION_STRING \
- " libpng version 1.5.9 - February 18, 2012\n"
+ " libpng version 1.5.13 - September 27, 2012\n"
#define PNG_LIBPNG_VER_SONUM 15
#define PNG_LIBPNG_VER_DLLNUM 15
@@ -389,7 +399,7 @@ /* These should match the first 3 components of PNG_LIBPNG_VER_STRING: */
#define PNG_LIBPNG_VER_MAJOR 1
#define PNG_LIBPNG_VER_MINOR 5
-#define PNG_LIBPNG_VER_RELEASE 9
+#define PNG_LIBPNG_VER_RELEASE 13
/* This should match the numeric part of the final component of
* PNG_LIBPNG_VER_STRING, omitting any leading zero:
@@ -412,7 +422,7 @@ #define PNG_LIBPNG_BUILD_SPECIAL 32 /* Cannot be OR'ed with
PNG_LIBPNG_BUILD_PRIVATE */
-#define PNG_LIBPNG_BUILD_BASE_TYPE PNG_LIBPNG_BUILD_BETA
+#define PNG_LIBPNG_BUILD_BASE_TYPE PNG_LIBPNG_BUILD_STABLE
/* Careful here. At one time, Guy wanted to use 082, but that would be octal.
* We must not include leading zeros.
@@ -420,7 +430,7 @@ * version 1.0.0 was mis-numbered 100 instead of 10000). From
* version 1.0.1 it's xxyyzz, where x=major, y=minor, z=release
*/
-#define PNG_LIBPNG_VER 10509 /* 1.5.9 */
+#define PNG_LIBPNG_VER 10513 /* 1.5.13 */
/* Library configuration: these options cannot be changed after
* the library has been built.
@@ -542,7 +552,7 @@ extern "C" { /* This triggers a compiler error in png.c, if png.c and png.h
* do not agree upon the version number.
*/
-typedef char* png_libpng_version_1_5_9;
+typedef char* png_libpng_version_1_5_13;
/* Three color definitions. The order of the red, green, and blue, (and the
* exact size) is not important, although the size of the fields need to
@@ -1151,9 +1161,9 @@ PNG_EXPORT(31, void, png_set_gray_to_rgb, (png_structp png_ptr)); #define PNG_RGB_TO_GRAY_DEFAULT (-1)/*for red/green coefficients*/
PNG_FP_EXPORT(32, void, png_set_rgb_to_gray, (png_structp png_ptr,
- int error_action, double red, double green));
+ int error_action, double red, double green))
PNG_FIXED_EXPORT(33, void, png_set_rgb_to_gray_fixed, (png_structp png_ptr,
- int error_action, png_fixed_point red, png_fixed_point green));
+ int error_action, png_fixed_point red, png_fixed_point green))
PNG_EXPORT(34, png_byte, png_get_rgb_to_gray_status, (png_const_structp
png_ptr));
@@ -1221,9 +1231,9 @@ PNG_EXPORT(35, void, png_build_grayscale_palette, (int bit_depth, #define PNG_ALPHA_BROKEN 3 /* the alpha channel is gamma encoded */
PNG_FP_EXPORT(227, void, png_set_alpha_mode, (png_structp png_ptr, int mode,
- double output_gamma));
+ double output_gamma))
PNG_FIXED_EXPORT(228, void, png_set_alpha_mode_fixed, (png_structp png_ptr,
- int mode, png_fixed_point output_gamma));
+ int mode, png_fixed_point output_gamma))
#endif
#if defined(PNG_READ_GAMMA_SUPPORTED) || defined(PNG_READ_ALPHA_MODE_SUPPORTED)
@@ -1446,10 +1456,10 @@ PNG_EXPORT(46, void, png_set_invert_mono, (png_structp png_ptr)); */
PNG_FP_EXPORT(47, void, png_set_background, (png_structp png_ptr,
png_const_color_16p background_color, int background_gamma_code,
- int need_expand, double background_gamma));
+ int need_expand, double background_gamma))
PNG_FIXED_EXPORT(215, void, png_set_background_fixed, (png_structp png_ptr,
png_const_color_16p background_color, int background_gamma_code,
- int need_expand, png_fixed_point background_gamma));
+ int need_expand, png_fixed_point background_gamma))
#endif
#ifdef PNG_READ_BACKGROUND_SUPPORTED
# define PNG_BACKGROUND_GAMMA_UNKNOWN 0
@@ -1498,9 +1508,9 @@ PNG_EXPORT(49, void, png_set_quantize, */
PNG_FP_EXPORT(50, void, png_set_gamma,
(png_structp png_ptr, double screen_gamma,
- double override_file_gamma));
+ double override_file_gamma))
PNG_FIXED_EXPORT(208, void, png_set_gamma_fixed, (png_structp png_ptr,
- png_fixed_point screen_gamma, png_fixed_point override_file_gamma));
+ png_fixed_point screen_gamma, png_fixed_point override_file_gamma))
#endif
#ifdef PNG_WRITE_FLUSH_SUPPORTED
@@ -1660,11 +1670,11 @@ PNG_EXPORT(67, void, png_set_filter, */
PNG_FP_EXPORT(68, void, png_set_filter_heuristics, (png_structp png_ptr,
int heuristic_method, int num_weights, png_const_doublep filter_weights,
- png_const_doublep filter_costs));
+ png_const_doublep filter_costs))
PNG_FIXED_EXPORT(209, void, png_set_filter_heuristics_fixed,
(png_structp png_ptr,
int heuristic_method, int num_weights, png_const_fixed_point_p
- filter_weights, png_const_fixed_point_p filter_costs));
+ filter_weights, png_const_fixed_point_p filter_costs))
#endif /* PNG_WRITE_WEIGHTED_FILTER_SUPPORTED */
/* Heuristic used for row filter selection. These defines should NOT be
@@ -2046,9 +2056,9 @@ PNG_EXPORT(124, png_uint_32, png_get_y_pixels_per_meter, /* Returns pixel aspect ratio, computed from pHYs chunk data. */
PNG_FP_EXPORT(125, float, png_get_pixel_aspect_ratio,
- (png_const_structp png_ptr, png_const_infop info_ptr));
+ (png_const_structp png_ptr, png_const_infop info_ptr))
PNG_FIXED_EXPORT(210, png_fixed_point, png_get_pixel_aspect_ratio_fixed,
- (png_const_structp png_ptr, png_const_infop info_ptr));
+ (png_const_structp png_ptr, png_const_infop info_ptr))
/* Returns image x, y offset in pixels or microns, from oFFs chunk data. */
PNG_EXPORT(126, png_int_32, png_get_x_offset_pixels,
@@ -2081,11 +2091,11 @@ PNG_EXPORT(132, void, png_set_bKGD, (png_structp png_ptr, png_infop info_ptr, PNG_FP_EXPORT(133, png_uint_32, 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));
+ double *blue_y))
PNG_FP_EXPORT(230, png_uint_32, png_get_cHRM_XYZ, (png_structp png_ptr,
png_const_infop info_ptr, double *red_X, double *red_Y, double *red_Z,
double *green_X, double *green_Y, double *green_Z, double *blue_X,
- double *blue_Y, double *blue_Z));
+ double *blue_Y, double *blue_Z))
#ifdef PNG_FIXED_POINT_SUPPORTED /* Otherwise not implemented */
PNG_FIXED_EXPORT(134, png_uint_32, png_get_cHRM_fixed,
(png_const_structp png_ptr,
@@ -2093,7 +2103,7 @@ PNG_FIXED_EXPORT(134, png_uint_32, png_get_cHRM_fixed, png_fixed_point *int_white_y, png_fixed_point *int_red_x,
png_fixed_point *int_red_y, png_fixed_point *int_green_x,
png_fixed_point *int_green_y, png_fixed_point *int_blue_x,
- png_fixed_point *int_blue_y));
+ png_fixed_point *int_blue_y))
#endif
PNG_FIXED_EXPORT(231, png_uint_32, png_get_cHRM_XYZ_fixed,
(png_structp png_ptr, png_const_infop info_ptr,
@@ -2101,46 +2111,46 @@ PNG_FIXED_EXPORT(231, png_uint_32, png_get_cHRM_XYZ_fixed, png_fixed_point *int_red_Z, png_fixed_point *int_green_X,
png_fixed_point *int_green_Y, png_fixed_point *int_green_Z,
png_fixed_point *int_blue_X, png_fixed_point *int_blue_Y,
- png_fixed_point *int_blue_Z));
+ png_fixed_point *int_blue_Z))
#endif
#ifdef PNG_cHRM_SUPPORTED
PNG_FP_EXPORT(135, void, png_set_cHRM,
(png_structp png_ptr, png_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));
+ double green_y, double blue_x, double blue_y))
PNG_FP_EXPORT(232, void, png_set_cHRM_XYZ, (png_structp png_ptr,
png_infop info_ptr, double red_X, double red_Y, double red_Z,
double green_X, double green_Y, double green_Z, double blue_X,
- double blue_Y, double blue_Z));
+ double blue_Y, double blue_Z))
PNG_FIXED_EXPORT(136, void, png_set_cHRM_fixed, (png_structp png_ptr,
png_infop info_ptr, png_fixed_point int_white_x,
png_fixed_point int_white_y, png_fixed_point int_red_x,
png_fixed_point int_red_y, png_fixed_point int_green_x,
png_fixed_point int_green_y, png_fixed_point int_blue_x,
- png_fixed_point int_blue_y));
+ png_fixed_point int_blue_y))
PNG_FIXED_EXPORT(233, void, png_set_cHRM_XYZ_fixed, (png_structp png_ptr,
png_infop info_ptr, png_fixed_point int_red_X, png_fixed_point int_red_Y,
png_fixed_point int_red_Z, png_fixed_point int_green_X,
png_fixed_point int_green_Y, png_fixed_point int_green_Z,
png_fixed_point int_blue_X, png_fixed_point int_blue_Y,
- png_fixed_point int_blue_Z));
+ png_fixed_point int_blue_Z))
#endif
#ifdef PNG_gAMA_SUPPORTED
PNG_FP_EXPORT(137, png_uint_32, png_get_gAMA,
(png_const_structp png_ptr, png_const_infop info_ptr,
- double *file_gamma));
+ double *file_gamma))
PNG_FIXED_EXPORT(138, png_uint_32, png_get_gAMA_fixed,
(png_const_structp png_ptr, png_const_infop info_ptr,
- png_fixed_point *int_file_gamma));
+ png_fixed_point *int_file_gamma))
#endif
#ifdef PNG_gAMA_SUPPORTED
PNG_FP_EXPORT(139, void, png_set_gAMA, (png_structp png_ptr,
- png_infop info_ptr, double file_gamma));
+ png_infop info_ptr, double file_gamma))
PNG_FIXED_EXPORT(140, void, png_set_gAMA_fixed, (png_structp png_ptr,
- png_infop info_ptr, png_fixed_point int_file_gamma));
+ png_infop info_ptr, png_fixed_point int_file_gamma))
#endif
#ifdef PNG_hIST_SUPPORTED
@@ -2306,7 +2316,7 @@ PNG_EXPORT(167, void, png_set_tRNS, #ifdef PNG_sCAL_SUPPORTED
PNG_FP_EXPORT(168, png_uint_32, png_get_sCAL,
(png_const_structp png_ptr, png_const_infop info_ptr,
- int *unit, double *width, double *height));
+ int *unit, double *width, double *height))
#ifdef PNG_FLOATING_ARITHMETIC_SUPPORTED
/* NOTE: this API is currently implemented using floating point arithmetic,
* consequently it can only be used on systems with floating point support.
@@ -2316,7 +2326,7 @@ PNG_FP_EXPORT(168, png_uint_32, png_get_sCAL, PNG_FIXED_EXPORT(214, png_uint_32, png_get_sCAL_fixed,
(png_structp png_ptr, png_const_infop info_ptr, int *unit,
png_fixed_point *width,
- png_fixed_point *height));
+ png_fixed_point *height))
#endif
PNG_EXPORT(169, png_uint_32, png_get_sCAL_s,
(png_const_structp png_ptr, png_const_infop info_ptr,
@@ -2324,10 +2334,10 @@ PNG_EXPORT(169, png_uint_32, png_get_sCAL_s, PNG_FP_EXPORT(170, void, png_set_sCAL,
(png_structp png_ptr, png_infop info_ptr,
- int unit, double width, double height));
+ int unit, double width, double height))
PNG_FIXED_EXPORT(213, void, png_set_sCAL_fixed, (png_structp png_ptr,
png_infop info_ptr, int unit, png_fixed_point width,
- png_fixed_point height));
+ png_fixed_point height))
PNG_EXPORT(171, void, png_set_sCAL_s,
(png_structp png_ptr, png_infop info_ptr,
int unit, png_const_charp swidth, png_const_charp sheight));
@@ -2440,17 +2450,17 @@ PNG_EXPORT(195, png_uint_32, png_get_y_pixels_per_inch, (png_const_structp png_ptr, png_const_infop info_ptr));
PNG_FP_EXPORT(196, float, png_get_x_offset_inches,
- (png_const_structp png_ptr, png_const_infop info_ptr));
+ (png_const_structp png_ptr, png_const_infop info_ptr))
#ifdef PNG_FIXED_POINT_SUPPORTED /* otherwise not implemented. */
PNG_FIXED_EXPORT(211, png_fixed_point, png_get_x_offset_inches_fixed,
- (png_structp png_ptr, png_const_infop info_ptr));
+ (png_structp png_ptr, png_const_infop info_ptr))
#endif
PNG_FP_EXPORT(197, float, png_get_y_offset_inches, (png_const_structp png_ptr,
- png_const_infop info_ptr));
+ png_const_infop info_ptr))
#ifdef PNG_FIXED_POINT_SUPPORTED /* otherwise not implemented. */
PNG_FIXED_EXPORT(212, png_fixed_point, png_get_y_offset_inches_fixed,
- (png_structp png_ptr, png_const_infop info_ptr));
+ (png_structp png_ptr, png_const_infop info_ptr))
#endif
# ifdef PNG_pHYs_SUPPORTED
@@ -2637,6 +2647,12 @@ PNG_EXPORT(207, void, png_save_uint_16, (png_bytep buf, unsigned int i)); : (png_int_32)png_get_uint_32(buf)))
#endif
+#if defined(PNG_READ_CHECK_FOR_INVALID_INDEX_SUPPORTED) || \
+ defined(PNG_WRITE_CHECK_FOR_INVALID_INDEX_SUPPORTED)
+PNG_EXPORT(234, void, png_set_check_for_invalid_index, (png_structp png_ptr,
+ int allowed));
+#endif
+
/* Maintainer: Put new public prototypes here ^, in libpng.3, and project
* defs
*/
@@ -2646,7 +2662,7 @@ PNG_EXPORT(207, void, png_save_uint_16, (png_bytep buf, unsigned int i)); * scripts/symbols.def as well.
*/
#ifdef PNG_EXPORT_LAST_ORDINAL
- PNG_EXPORT_LAST_ORDINAL(233);
+ PNG_EXPORT_LAST_ORDINAL(234);
#endif
#ifdef __cplusplus
diff --git a/plugins/AdvaImg/src/LibPNG/pngconf.h b/plugins/AdvaImg/src/LibPNG/pngconf.h index 121d204ccd..5298e667a8 100644 --- a/plugins/AdvaImg/src/LibPNG/pngconf.h +++ b/plugins/AdvaImg/src/LibPNG/pngconf.h @@ -1,7 +1,7 @@ /* pngconf.h - machine configurable file for libpng
*
- * libpng version 1.5.9 - February 18, 2012
+ * libpng version 1.5.13 - September 27, 2012
*
* Copyright (c) 1998-2012 Glenn Randers-Pehrson
* (Version 0.96 Copyright (c) 1996, 1997 Andreas Dilger)
@@ -25,7 +25,7 @@ #ifndef PNG_BUILDING_SYMBOL_TABLE
/* PNG_NO_LIMITS_H may be used to turn off the use of the standard C
* definition file for machine specific limits, this may impact the
- * correctness of the definitons below (see uses of INT_MAX).
+ * correctness of the definitions below (see uses of INT_MAX).
*/
# ifndef PNG_NO_LIMITS_H
# include <limits.h>
@@ -51,8 +51,8 @@ /* This controls optimization of the reading of 16 and 32 bit values
* from PNG files. It can be set on a per-app-file basis - it
- * just changes whether a macro is used to the function is called.
- * The library builder sets the default, if read functions are not
+ * just changes whether a macro is used when the function is called.
+ * The library builder sets the default; if read functions are not
* built into the library the macro implementation is forced on.
*/
#ifndef PNG_READ_INT_FUNCTIONS_SUPPORTED
@@ -182,9 +182,9 @@ * conventions of the various functions.
*/
#if ( defined(_Windows) || defined(_WINDOWS) || defined(WIN32) ||\
- defined(_WIN32) || defined(__WIN32__) || defined(__CYGWIN__)) &&\
+ defined(_WIN32) || defined(__WIN32__) || defined(__CYGWIN__) ) &&\
( defined(_X86_) || defined(_X64_) || defined(_M_IX86) ||\
- defined(_M_X64) || defined(_M_IA64))
+ defined(_M_X64) || defined(_M_IA64) )
/* Windows system (DOS doesn't support DLLs) running on x86/x64. Includes
* builds under Cygwin or MinGW. Also includes Watcom builds but these need
* special treatment because they are not compatible with GCC or Visual C
@@ -344,21 +344,23 @@ # ifndef PNG_NORETURN
# define PNG_NORETURN __attribute__((__noreturn__))
# endif
-# ifndef PNG_ALLOCATED
-# define PNG_ALLOCATED __attribute__((__malloc__))
-# endif
-# ifndef PNG_DEPRECATED
-# define PNG_DEPRECATED __attribute__((__deprecated__))
-# endif
-# ifndef PNG_PRIVATE
-# if 0 /* Doesn't work so we use deprecated instead*/
-# define PNG_PRIVATE \
- __attribute__((warning("This function is not exported by libpng.")))
-# else
-# define PNG_PRIVATE \
- __attribute__((__deprecated__))
+# if __GNUC__ >= 3
+# ifndef PNG_ALLOCATED
+# define PNG_ALLOCATED __attribute__((__malloc__))
# endif
-# endif
+# ifndef PNG_DEPRECATED
+# define PNG_DEPRECATED __attribute__((__deprecated__))
+# endif
+# ifndef PNG_PRIVATE
+# if 0 /* Doesn't work so we use deprecated instead*/
+# define PNG_PRIVATE \
+ __attribute__((warning("This function is not exported by libpng.")))
+# else
+# define PNG_PRIVATE \
+ __attribute__((__deprecated__))
+# endif
+# endif
+# endif /* __GNUC__ >= 3 */
# endif /* __GNUC__ */
# if defined(_MSC_VER) && (_MSC_VER >= 1300)
@@ -400,7 +402,7 @@ #ifndef PNG_FP_EXPORT /* A floating point API. */
# ifdef PNG_FLOATING_POINT_SUPPORTED
# define PNG_FP_EXPORT(ordinal, type, name, args)\
- PNG_EXPORT(ordinal, type, name, args)
+ PNG_EXPORT(ordinal, type, name, args);
# else /* No floating point APIs */
# define PNG_FP_EXPORT(ordinal, type, name, args)
# endif
@@ -408,7 +410,7 @@ #ifndef PNG_FIXED_EXPORT /* A fixed point API. */
# ifdef PNG_FIXED_POINT_SUPPORTED
# define PNG_FIXED_EXPORT(ordinal, type, name, args)\
- PNG_EXPORT(ordinal, type, name, args)
+ PNG_EXPORT(ordinal, type, name, args);
# else /* No fixed point APIs */
# define PNG_FIXED_EXPORT(ordinal, type, name, args)
# endif
diff --git a/plugins/AdvaImg/src/LibPNG/pngerror.c b/plugins/AdvaImg/src/LibPNG/pngerror.c index 9df97f583c..ef60d553fd 100644 --- a/plugins/AdvaImg/src/LibPNG/pngerror.c +++ b/plugins/AdvaImg/src/LibPNG/pngerror.c @@ -2,7 +2,7 @@ /* pngerror.c - stub functions for i/o and memory allocation
*
* Last changed in libpng 1.5.8 [February 1, 2011]
- * Copyright (c) 1998-2012 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.)
*
diff --git a/plugins/AdvaImg/src/LibPNG/pngmem.c b/plugins/AdvaImg/src/LibPNG/pngmem.c index 25b5c73546..3099246cba 100644 --- a/plugins/AdvaImg/src/LibPNG/pngmem.c +++ b/plugins/AdvaImg/src/LibPNG/pngmem.c @@ -1,8 +1,8 @@ /* pngmem.c - stub functions for memory allocation
*
- * Last changed in libpng 1.5.7 [December 15, 2011]
- * Copyright (c) 1998-2011 Glenn Randers-Pehrson
+ * Last changed in libpng 1.5.13 [September 27, 2012]
+ * Copyright (c) 1998-2012 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.)
*
@@ -56,7 +56,7 @@ png_create_struct_2,(int type, png_malloc_ptr malloc_fn, png_voidp mem_ptr), if (malloc_fn != NULL)
{
png_struct dummy_struct;
- memset(&dummy_struct, 0, sizeof dummy_struct);
+ png_memset(&dummy_struct, 0, sizeof dummy_struct);
dummy_struct.mem_ptr=mem_ptr;
struct_ptr = (*(malloc_fn))(&dummy_struct, (png_alloc_size_t)size);
}
@@ -90,7 +90,7 @@ png_destroy_struct_2(png_voidp struct_ptr, png_free_ptr free_fn, if (free_fn != NULL)
{
png_struct dummy_struct;
- memset(&dummy_struct, 0, sizeof dummy_struct);
+ png_memset(&dummy_struct, 0, sizeof dummy_struct);
dummy_struct.mem_ptr=mem_ptr;
(*(free_fn))(&dummy_struct, struct_ptr);
return;
diff --git a/plugins/AdvaImg/src/LibPNG/pngpread.c b/plugins/AdvaImg/src/LibPNG/pngpread.c index eda5a6c80f..39f8f6fa9d 100644 --- a/plugins/AdvaImg/src/LibPNG/pngpread.c +++ b/plugins/AdvaImg/src/LibPNG/pngpread.c @@ -1,8 +1,8 @@ /* pngpread.c - read a png file in push mode
*
- * Last changed in libpng 1.5.9 [February 18, 2012]
- * Copyright (c) 1998-2011 Glenn Randers-Pehrson
+ * Last changed in libpng 1.5.11 [June 14, 2012]
+ * Copyright (c) 1998-2012 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.)
*
@@ -128,30 +128,6 @@ png_process_some_data(png_structp png_ptr, png_infop info_ptr) break;
}
-#ifdef PNG_READ_tEXt_SUPPORTED
- case PNG_READ_tEXt_MODE:
- {
- png_push_read_tEXt(png_ptr, info_ptr);
- break;
- }
-
-#endif
-#ifdef PNG_READ_zTXt_SUPPORTED
- case PNG_READ_zTXt_MODE:
- {
- png_push_read_zTXt(png_ptr, info_ptr);
- break;
- }
-
-#endif
-#ifdef PNG_READ_iTXt_SUPPORTED
- case PNG_READ_iTXt_MODE:
- {
- png_push_read_iTXt(png_ptr, info_ptr);
- break;
- }
-
-#endif
case PNG_SKIP_MODE:
{
png_push_crc_finish(png_ptr);
@@ -176,7 +152,7 @@ void /* PRIVATE */ png_push_read_sig(png_structp png_ptr, png_infop info_ptr)
{
png_size_t num_checked = png_ptr->sig_bytes,
- num_to_check = 8 - num_checked;
+ num_to_check = 8 - num_checked;
if (png_ptr->buffer_size < num_to_check)
{
@@ -196,6 +172,7 @@ png_push_read_sig(png_structp png_ptr, png_infop info_ptr) else
png_error(png_ptr, "PNG file corrupted by ASCII conversion");
}
+
else
{
if (png_ptr->sig_bytes >= 8)
@@ -305,8 +282,8 @@ png_push_read_chunk(png_structp png_ptr, png_infop info_ptr) png_error(png_ptr, "Missing PLTE before IDAT");
}
}
-
#endif
+
else if (chunk_name == png_PLTE)
{
if (png_ptr->push_length + 4 > png_ptr->buffer_size)
@@ -543,7 +520,7 @@ png_push_read_chunk(png_structp png_ptr, png_infop info_ptr) return;
}
- png_push_handle_tEXt(png_ptr, info_ptr, png_ptr->push_length);
+ png_handle_tEXt(png_ptr, info_ptr, png_ptr->push_length);
}
#endif
@@ -556,7 +533,7 @@ png_push_read_chunk(png_structp png_ptr, png_infop info_ptr) return;
}
- png_push_handle_zTXt(png_ptr, info_ptr, png_ptr->push_length);
+ png_handle_zTXt(png_ptr, info_ptr, png_ptr->push_length);
}
#endif
@@ -569,10 +546,11 @@ png_push_read_chunk(png_structp png_ptr, png_infop info_ptr) return;
}
- png_push_handle_iTXt(png_ptr, info_ptr, png_ptr->push_length);
+ png_handle_iTXt(png_ptr, info_ptr, png_ptr->push_length);
}
#endif
+
else
{
if (png_ptr->push_length + 4 > png_ptr->buffer_size)
@@ -580,7 +558,7 @@ png_push_read_chunk(png_structp png_ptr, png_infop info_ptr) png_push_save_buffer(png_ptr);
return;
}
- png_push_handle_unknown(png_ptr, info_ptr, png_ptr->push_length);
+ png_handle_unknown(png_ptr, info_ptr, png_ptr->push_length);
}
png_ptr->mode &= ~PNG_HAVE_CHUNK_HEADER;
@@ -620,6 +598,7 @@ png_push_crc_finish(png_structp png_ptr) png_ptr->save_buffer_size -= save_size;
png_ptr->save_buffer_ptr += save_size;
}
+
if (png_ptr->skip_length && png_ptr->current_buffer_size)
{
png_size_t save_size = png_ptr->current_buffer_size;
@@ -641,6 +620,7 @@ png_push_crc_finish(png_structp png_ptr) png_ptr->current_buffer_size -= save_size;
png_ptr->current_buffer_ptr += save_size;
}
+
if (!png_ptr->skip_length)
{
if (png_ptr->buffer_size < 4)
@@ -663,6 +643,7 @@ png_push_fill_buffer(png_structp png_ptr, png_bytep buffer, png_size_t length) return;
ptr = buffer;
+
if (png_ptr->save_buffer_size)
{
png_size_t save_size;
@@ -680,6 +661,7 @@ png_push_fill_buffer(png_structp png_ptr, png_bytep buffer, png_size_t length) png_ptr->save_buffer_size -= save_size;
png_ptr->save_buffer_ptr += save_size;
}
+
if (length && png_ptr->current_buffer_size)
{
png_size_t save_size;
@@ -709,6 +691,7 @@ png_push_save_buffer(png_structp png_ptr) png_bytep dp;
istop = png_ptr->save_buffer_size;
+
for (i = 0, sp = png_ptr->save_buffer_ptr, dp = png_ptr->save_buffer;
i < istop; i++, sp++, dp++)
{
@@ -716,6 +699,7 @@ png_push_save_buffer(png_structp png_ptr) }
}
}
+
if (png_ptr->save_buffer_size + png_ptr->current_buffer_size >
png_ptr->save_buffer_max)
{
@@ -742,6 +726,7 @@ png_push_save_buffer(png_structp png_ptr) png_free(png_ptr, old_buffer);
png_ptr->save_buffer_max = new_max;
}
+
if (png_ptr->current_buffer_size)
{
png_memcpy(png_ptr->save_buffer + png_ptr->save_buffer_size,
@@ -749,6 +734,7 @@ png_push_save_buffer(png_structp png_ptr) png_ptr->save_buffer_size += png_ptr->current_buffer_size;
png_ptr->current_buffer_size = 0;
}
+
png_ptr->save_buffer_ptr = png_ptr->save_buffer;
png_ptr->buffer_size = 0;
}
@@ -850,6 +836,7 @@ png_push_read_IDAT(png_structp png_ptr) png_ptr->current_buffer_size -= save_size;
png_ptr->current_buffer_ptr += save_size;
}
+
if (!png_ptr->idat_size)
{
if (png_ptr->buffer_size < 4)
@@ -1263,521 +1250,6 @@ png_read_push_finish_row(png_structp png_ptr) #endif /* PNG_READ_INTERLACING_SUPPORTED */
}
-#ifdef PNG_READ_tEXt_SUPPORTED
-void /* PRIVATE */
-png_push_handle_tEXt(png_structp png_ptr, png_infop info_ptr, png_uint_32
- length)
-{
- if (!(png_ptr->mode & PNG_HAVE_IHDR) || (png_ptr->mode & PNG_HAVE_IEND))
- {
- PNG_UNUSED(info_ptr) /* To quiet some compiler warnings */
- png_error(png_ptr, "Out of place tEXt");
- /* NOT REACHED */
- }
-
-#ifdef PNG_MAX_MALLOC_64K
- png_ptr->skip_length = 0; /* This may not be necessary */
-
- if (length > (png_uint_32)65535L) /* Can't hold entire string in memory */
- {
- png_warning(png_ptr, "tEXt chunk too large to fit in memory");
- png_ptr->skip_length = length - (png_uint_32)65535L;
- length = (png_uint_32)65535L;
- }
-#endif
-
- png_ptr->current_text = (png_charp)png_malloc(png_ptr, length + 1);
- png_ptr->current_text[length] = '\0';
- png_ptr->current_text_ptr = png_ptr->current_text;
- png_ptr->current_text_size = (png_size_t)length;
- png_ptr->current_text_left = (png_size_t)length;
- png_ptr->process_mode = PNG_READ_tEXt_MODE;
-}
-
-void /* PRIVATE */
-png_push_read_tEXt(png_structp png_ptr, png_infop info_ptr)
-{
- if (png_ptr->buffer_size && png_ptr->current_text_left)
- {
- png_size_t text_size;
-
- if (png_ptr->buffer_size < png_ptr->current_text_left)
- text_size = png_ptr->buffer_size;
-
- else
- text_size = png_ptr->current_text_left;
-
- png_crc_read(png_ptr, (png_bytep)png_ptr->current_text_ptr, text_size);
- png_ptr->current_text_left -= text_size;
- png_ptr->current_text_ptr += text_size;
- }
- if (!(png_ptr->current_text_left))
- {
- png_textp text_ptr;
- png_charp text;
- png_charp key;
- int ret;
-
- if (png_ptr->buffer_size < 4)
- {
- png_push_save_buffer(png_ptr);
- return;
- }
-
- png_push_crc_finish(png_ptr);
-
-#ifdef PNG_MAX_MALLOC_64K
- if (png_ptr->skip_length)
- return;
-#endif
-
- key = png_ptr->current_text;
-
- for (text = key; *text; text++)
- /* Empty loop */ ;
-
- if (text < key + png_ptr->current_text_size)
- text++;
-
- text_ptr = (png_textp)png_malloc(png_ptr, png_sizeof(png_text));
- text_ptr->compression = PNG_TEXT_COMPRESSION_NONE;
- text_ptr->key = key;
- text_ptr->itxt_length = 0;
- text_ptr->lang = NULL;
- text_ptr->lang_key = NULL;
- text_ptr->text = text;
-
- ret = png_set_text_2(png_ptr, info_ptr, text_ptr, 1);
-
- png_free(png_ptr, key);
- png_free(png_ptr, text_ptr);
- png_ptr->current_text = NULL;
-
- if (ret)
- png_warning(png_ptr, "Insufficient memory to store text chunk");
- }
-}
-#endif
-
-#ifdef PNG_READ_zTXt_SUPPORTED
-void /* PRIVATE */
-png_push_handle_zTXt(png_structp png_ptr, png_infop info_ptr, png_uint_32
- length)
-{
- if (!(png_ptr->mode & PNG_HAVE_IHDR) || (png_ptr->mode & PNG_HAVE_IEND))
- {
- PNG_UNUSED(info_ptr) /* To quiet some compiler warnings */
- png_error(png_ptr, "Out of place zTXt");
- /* NOT REACHED */
- }
-
-#ifdef PNG_MAX_MALLOC_64K
- /* We can't handle zTXt chunks > 64K, since we don't have enough space
- * to be able to store the uncompressed data. Actually, the threshold
- * is probably around 32K, but it isn't as definite as 64K is.
- */
- if (length > (png_uint_32)65535L)
- {
- png_warning(png_ptr, "zTXt chunk too large to fit in memory");
- png_push_crc_skip(png_ptr, length);
- return;
- }
-#endif
-
- png_ptr->current_text = (png_charp)png_malloc(png_ptr, length + 1);
- png_ptr->current_text[length] = '\0';
- png_ptr->current_text_ptr = png_ptr->current_text;
- png_ptr->current_text_size = (png_size_t)length;
- png_ptr->current_text_left = (png_size_t)length;
- png_ptr->process_mode = PNG_READ_zTXt_MODE;
-}
-
-void /* PRIVATE */
-png_push_read_zTXt(png_structp png_ptr, png_infop info_ptr)
-{
- if (png_ptr->buffer_size && png_ptr->current_text_left)
- {
- png_size_t text_size;
-
- if (png_ptr->buffer_size < (png_uint_32)png_ptr->current_text_left)
- text_size = png_ptr->buffer_size;
-
- else
- text_size = png_ptr->current_text_left;
-
- png_crc_read(png_ptr, (png_bytep)png_ptr->current_text_ptr, text_size);
- png_ptr->current_text_left -= text_size;
- png_ptr->current_text_ptr += text_size;
- }
- if (!(png_ptr->current_text_left))
- {
- png_textp text_ptr;
- png_charp text;
- png_charp key;
- int ret;
- png_size_t text_size, key_size;
-
- if (png_ptr->buffer_size < 4)
- {
- png_push_save_buffer(png_ptr);
- return;
- }
-
- png_push_crc_finish(png_ptr);
-
- key = png_ptr->current_text;
-
- for (text = key; *text; text++)
- /* Empty loop */ ;
-
- /* zTXt can't have zero text */
- if (text >= key + png_ptr->current_text_size)
- {
- png_ptr->current_text = NULL;
- png_free(png_ptr, key);
- return;
- }
-
- text++;
-
- if (*text != PNG_TEXT_COMPRESSION_zTXt) /* Check compression byte */
- {
- png_ptr->current_text = NULL;
- png_free(png_ptr, key);
- return;
- }
-
- text++;
-
- png_ptr->zstream.next_in = (png_bytep)text;
- png_ptr->zstream.avail_in = (uInt)(png_ptr->current_text_size -
- (text - key));
- png_ptr->zstream.next_out = png_ptr->zbuf;
- png_ptr->zstream.avail_out = (uInt)png_ptr->zbuf_size;
-
- key_size = text - key;
- text_size = 0;
- text = NULL;
- ret = Z_STREAM_END;
-
- while (png_ptr->zstream.avail_in)
- {
- ret = inflate(&png_ptr->zstream, Z_PARTIAL_FLUSH);
- if (ret != Z_OK && ret != Z_STREAM_END)
- {
- inflateReset(&png_ptr->zstream);
- png_ptr->zstream.avail_in = 0;
- png_ptr->current_text = NULL;
- png_free(png_ptr, key);
- png_free(png_ptr, text);
- return;
- }
-
- if (!(png_ptr->zstream.avail_out) || ret == Z_STREAM_END)
- {
- if (text == NULL)
- {
- text = (png_charp)png_malloc(png_ptr,
- (png_ptr->zbuf_size
- - png_ptr->zstream.avail_out + key_size + 1));
-
- png_memcpy(text + key_size, png_ptr->zbuf,
- png_ptr->zbuf_size - png_ptr->zstream.avail_out);
-
- png_memcpy(text, key, key_size);
-
- text_size = key_size + png_ptr->zbuf_size -
- png_ptr->zstream.avail_out;
-
- *(text + text_size) = '\0';
- }
-
- else
- {
- png_charp tmp;
-
- tmp = text;
- text = (png_charp)png_malloc(png_ptr, text_size +
- (png_ptr->zbuf_size
- - png_ptr->zstream.avail_out + 1));
-
- png_memcpy(text, tmp, text_size);
- png_free(png_ptr, tmp);
-
- png_memcpy(text + text_size, png_ptr->zbuf,
- png_ptr->zbuf_size - png_ptr->zstream.avail_out);
-
- text_size += png_ptr->zbuf_size - png_ptr->zstream.avail_out;
- *(text + text_size) = '\0';
- }
-
- if (ret != Z_STREAM_END)
- {
- png_ptr->zstream.next_out = png_ptr->zbuf;
- png_ptr->zstream.avail_out = (uInt)png_ptr->zbuf_size;
- }
- }
- else
- {
- break;
- }
-
- if (ret == Z_STREAM_END)
- break;
- }
-
- inflateReset(&png_ptr->zstream);
- png_ptr->zstream.avail_in = 0;
-
- if (ret != Z_STREAM_END)
- {
- png_ptr->current_text = NULL;
- png_free(png_ptr, key);
- png_free(png_ptr, text);
- return;
- }
-
- png_ptr->current_text = NULL;
- png_free(png_ptr, key);
- key = text;
- text += key_size;
-
- text_ptr = (png_textp)png_malloc(png_ptr,
- png_sizeof(png_text));
- text_ptr->compression = PNG_TEXT_COMPRESSION_zTXt;
- text_ptr->key = key;
- text_ptr->itxt_length = 0;
- text_ptr->lang = NULL;
- text_ptr->lang_key = NULL;
- text_ptr->text = text;
-
- ret = png_set_text_2(png_ptr, info_ptr, text_ptr, 1);
-
- png_free(png_ptr, key);
- png_free(png_ptr, text_ptr);
-
- if (ret)
- png_warning(png_ptr, "Insufficient memory to store text chunk");
- }
-}
-#endif
-
-#ifdef PNG_READ_iTXt_SUPPORTED
-void /* PRIVATE */
-png_push_handle_iTXt(png_structp png_ptr, png_infop info_ptr, png_uint_32
- length)
-{
- if (!(png_ptr->mode & PNG_HAVE_IHDR) || (png_ptr->mode & PNG_HAVE_IEND))
- {
- PNG_UNUSED(info_ptr) /* To quiet some compiler warnings */
- png_error(png_ptr, "Out of place iTXt");
- /* NOT REACHED */
- }
-
-#ifdef PNG_MAX_MALLOC_64K
- png_ptr->skip_length = 0; /* This may not be necessary */
-
- if (length > (png_uint_32)65535L) /* Can't hold entire string in memory */
- {
- png_warning(png_ptr, "iTXt chunk too large to fit in memory");
- png_ptr->skip_length = length - (png_uint_32)65535L;
- length = (png_uint_32)65535L;
- }
-#endif
-
- png_ptr->current_text = (png_charp)png_malloc(png_ptr, length + 1);
- png_ptr->current_text[length] = '\0';
- png_ptr->current_text_ptr = png_ptr->current_text;
- png_ptr->current_text_size = (png_size_t)length;
- png_ptr->current_text_left = (png_size_t)length;
- png_ptr->process_mode = PNG_READ_iTXt_MODE;
-}
-
-void /* PRIVATE */
-png_push_read_iTXt(png_structp png_ptr, png_infop info_ptr)
-{
-
- if (png_ptr->buffer_size && png_ptr->current_text_left)
- {
- png_size_t text_size;
-
- if (png_ptr->buffer_size < png_ptr->current_text_left)
- text_size = png_ptr->buffer_size;
-
- else
- text_size = png_ptr->current_text_left;
-
- png_crc_read(png_ptr, (png_bytep)png_ptr->current_text_ptr, text_size);
- png_ptr->current_text_left -= text_size;
- png_ptr->current_text_ptr += text_size;
- }
-
- if (!(png_ptr->current_text_left))
- {
- png_textp text_ptr;
- png_charp key;
- int comp_flag;
- png_charp lang;
- png_charp lang_key;
- png_charp text;
- int ret;
-
- if (png_ptr->buffer_size < 4)
- {
- png_push_save_buffer(png_ptr);
- return;
- }
-
- png_push_crc_finish(png_ptr);
-
-#ifdef PNG_MAX_MALLOC_64K
- if (png_ptr->skip_length)
- return;
-#endif
-
- key = png_ptr->current_text;
-
- for (lang = key; *lang; lang++)
- /* Empty loop */ ;
-
- if (lang < key + png_ptr->current_text_size - 3)
- lang++;
-
- comp_flag = *lang++;
- lang++; /* Skip comp_type, always zero */
-
- for (lang_key = lang; *lang_key; lang_key++)
- /* Empty loop */ ;
-
- lang_key++; /* Skip NUL separator */
-
- text=lang_key;
-
- if (lang_key < key + png_ptr->current_text_size - 1)
- {
- for (; *text; text++)
- /* Empty loop */ ;
- }
-
- if (text < key + png_ptr->current_text_size)
- text++;
-
- text_ptr = (png_textp)png_malloc(png_ptr,
- png_sizeof(png_text));
-
- text_ptr->compression = comp_flag + 2;
- text_ptr->key = key;
- text_ptr->lang = lang;
- text_ptr->lang_key = lang_key;
- text_ptr->text = text;
- text_ptr->text_length = 0;
- text_ptr->itxt_length = png_strlen(text);
-
- ret = png_set_text_2(png_ptr, info_ptr, text_ptr, 1);
-
- png_ptr->current_text = NULL;
-
- png_free(png_ptr, text_ptr);
- if (ret)
- png_warning(png_ptr, "Insufficient memory to store iTXt chunk");
- }
-}
-#endif
-
-/* This function is called when we haven't found a handler for this
- * chunk. If there isn't a problem with the chunk itself (ie a bad chunk
- * name or a critical chunk), the chunk is (currently) silently ignored.
- */
-void /* PRIVATE */
-png_push_handle_unknown(png_structp png_ptr, png_infop info_ptr, png_uint_32
- length)
-{
- png_uint_32 skip = 0;
- png_uint_32 chunk_name = png_ptr->chunk_name;
-
- if (PNG_CHUNK_CRITICAL(chunk_name))
- {
-#ifdef PNG_READ_UNKNOWN_CHUNKS_SUPPORTED
- if (png_chunk_unknown_handling(png_ptr, chunk_name) !=
- PNG_HANDLE_CHUNK_ALWAYS
-#ifdef PNG_READ_USER_CHUNKS_SUPPORTED
- && png_ptr->read_user_chunk_fn == NULL
-#endif
- )
-#endif
- png_chunk_error(png_ptr, "unknown critical chunk");
-
- PNG_UNUSED(info_ptr) /* To quiet some compiler warnings */
- }
-
-#ifdef PNG_READ_UNKNOWN_CHUNKS_SUPPORTED
- /* TODO: the code below is apparently just using the
- * png_struct::unknown_chunk member as a temporarily variable, it should be
- * possible to eliminate both it and the temporary buffer.
- */
- if (png_ptr->flags & PNG_FLAG_KEEP_UNKNOWN_CHUNKS)
- {
-#ifdef PNG_MAX_MALLOC_64K
- if (length > 65535)
- {
- png_warning(png_ptr, "unknown chunk too large to fit in memory");
- skip = length - 65535;
- length = 65535;
- }
-#endif
- /* This is just a record for the user; libpng doesn't use the character
- * form of the name.
- */
- PNG_CSTRING_FROM_CHUNK(png_ptr->unknown_chunk.name, png_ptr->chunk_name);
-
- png_ptr->unknown_chunk.size = length;
-
- if (length == 0)
- png_ptr->unknown_chunk.data = NULL;
-
- else
- {
- png_ptr->unknown_chunk.data = (png_bytep)png_malloc(png_ptr,
- png_ptr->unknown_chunk.size);
- png_crc_read(png_ptr, (png_bytep)png_ptr->unknown_chunk.data,
- png_ptr->unknown_chunk.size);
- }
-
-#ifdef PNG_READ_USER_CHUNKS_SUPPORTED
- if (png_ptr->read_user_chunk_fn != NULL)
- {
- /* Callback to user unknown chunk handler */
- int ret;
- ret = (*(png_ptr->read_user_chunk_fn))
- (png_ptr, &png_ptr->unknown_chunk);
-
- if (ret < 0)
- png_chunk_error(png_ptr, "error in user chunk");
-
- if (ret == 0)
- {
- if (PNG_CHUNK_CRITICAL(png_ptr->chunk_name))
- if (png_chunk_unknown_handling(png_ptr, chunk_name) !=
- PNG_HANDLE_CHUNK_ALWAYS)
- png_chunk_error(png_ptr, "unknown critical chunk");
- png_set_unknown_chunks(png_ptr, info_ptr,
- &png_ptr->unknown_chunk, 1);
- }
- }
-
- else
-#endif
- png_set_unknown_chunks(png_ptr, info_ptr, &png_ptr->unknown_chunk, 1);
- png_free(png_ptr, png_ptr->unknown_chunk.data);
- png_ptr->unknown_chunk.data = NULL;
- }
-
- else
-#endif
- skip=length;
- png_push_crc_skip(png_ptr, skip);
-}
-
void /* PRIVATE */
png_push_have_info(png_structp png_ptr, png_infop info_ptr)
{
diff --git a/plugins/AdvaImg/src/LibPNG/pngpriv.h b/plugins/AdvaImg/src/LibPNG/pngpriv.h index 02cc5d8c53..3863f1f5cf 100644 --- a/plugins/AdvaImg/src/LibPNG/pngpriv.h +++ b/plugins/AdvaImg/src/LibPNG/pngpriv.h @@ -2,11 +2,11 @@ /* pngpriv.h - private declarations for use inside libpng
*
* For conditions of distribution and use, see copyright notice in png.h
- * Copyright (c) 1998-2011 Glenn Randers-Pehrson
+ * Copyright (c) 1998-2012 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 1.5.7 [December 15, 2011]
+ * Last changed in libpng 1.5.10 [March 29, 2012]
*
* This code is released under the libpng license.
* For conditions of distribution and use, see the disclaimer
@@ -133,6 +133,46 @@ # define PNG_DLL_EXPORT
#endif
+/* SECURITY and SAFETY:
+ *
+ * By default libpng is built without any internal limits on image size,
+ * individual heap (png_malloc) allocations or the total amount of memory used.
+ * If PNG_SAFE_LIMITS_SUPPORTED is defined, however, the limits below are used
+ * (unless individually overridden). These limits are believed to be fairly
+ * safe, but builders of secure systems should verify the values against the
+ * real system capabilities.
+ */
+
+#ifdef PNG_SAFE_LIMITS_SUPPORTED
+ /* 'safe' limits */
+# ifndef PNG_USER_WIDTH_MAX
+# define PNG_USER_WIDTH_MAX 1000000
+# endif
+# ifndef PNG_USER_HEIGHT_MAX
+# define PNG_USER_HEIGHT_MAX 1000000
+# endif
+# ifndef PNG_USER_CHUNK_CACHE_MAX
+# define PNG_USER_CHUNK_CACHE_MAX 128
+# endif
+# ifndef PNG_USER_CHUNK_MALLOC_MAX
+# define PNG_USER_CHUNK_MALLOC_MAX 8000000
+# endif
+#else
+ /* values for no limits */
+# ifndef PNG_USER_WIDTH_MAX
+# define PNG_USER_WIDTH_MAX 0x7fffffff
+# endif
+# ifndef PNG_USER_HEIGHT_MAX
+# define PNG_USER_HEIGHT_MAX 0x7fffffff
+# endif
+# ifndef PNG_USER_CHUNK_CACHE_MAX
+# define PNG_USER_CHUNK_CACHE_MAX 0
+# endif
+# ifndef PNG_USER_CHUNK_MALLOC_MAX
+# define PNG_USER_CHUNK_MALLOC_MAX 0
+# endif
+#endif
+
/* This is used for 16 bit gamma tables - only the top level pointers are const,
* this could be changed:
*/
@@ -426,6 +466,7 @@ typedef PNG_CONST png_uint_16p FAR * png_const_uint_16pp; #define PNG_BACKGROUND_IS_GRAY 0x800
#define PNG_HAVE_PNG_SIGNATURE 0x1000
#define PNG_HAVE_CHUNK_AFTER_IDAT 0x2000 /* Have another chunk after IDAT */
+#define PNG_HAVE_iCCP 0x4000
/* Flags for the transformations the PNG library does on the image data */
#define PNG_BGR 0x0001
@@ -532,7 +573,7 @@ typedef PNG_CONST png_uint_16p FAR * png_const_uint_16pp; #define PNG_ROWBYTES(pixel_bits, width) \
((pixel_bits) >= 8 ? \
((png_size_t)(width) * (((png_size_t)(pixel_bits)) >> 3)) : \
- (( ((png_size_t)(width) * ((png_size_t)(pixel_bits))) + 7) >> 3))
+ (( ((png_size_t)(width) * ((png_size_t)(pixel_bits))) + 7) >> 3) )
/* PNG_OUT_OF_RANGE returns true if value is outside the range
* ideal-delta..ideal+delta. Each argument is evaluated twice.
@@ -540,7 +581,7 @@ typedef PNG_CONST png_uint_16p FAR * png_const_uint_16pp; * integers, "value" a variable. Added to libpng-1.2.6 JB
*/
#define PNG_OUT_OF_RANGE(value, ideal, delta) \
- ( (value) < (ideal)-(delta) || (value) > (ideal)+(delta))
+ ( (value) < (ideal)-(delta) || (value) > (ideal)+(delta) )
/* Conversions between fixed and floating point, only defined if
* required (to make sure the code doesn't accidentally use float
@@ -952,8 +993,8 @@ PNG_EXTERN void png_do_write_interlace PNGARG((png_row_infop row_info, /* Unfilter a row: check the filter value before calling this, there is no point
* calling it for PNG_FILTER_VALUE_NONE.
*/
-PNG_EXTERN void png_read_filter_row PNGARG((png_structp pp, png_row_infop row_info,
- png_bytep row, png_const_bytep prev_row, int filter));
+PNG_EXTERN void png_read_filter_row PNGARG((png_structp pp, png_row_infop
+ row_info, png_bytep row, png_const_bytep prev_row, int filter));
PNG_EXTERN void png_read_filter_row_up_neon PNGARG((png_row_infop row_info,
png_bytep row, png_const_bytep prev_row));
@@ -1218,10 +1259,8 @@ PNG_EXTERN void png_handle_zTXt PNGARG((png_structp png_ptr, png_infop info_ptr, png_uint_32 length));
#endif
-#ifdef PNG_HANDLE_AS_UNKNOWN_SUPPORTED
PNG_EXTERN void png_handle_unknown PNGARG((png_structp png_ptr,
png_infop info_ptr, png_uint_32 length));
-#endif
PNG_EXTERN void png_check_chunk_name PNGARG((png_structp png_ptr,
png_uint_32 chunk_name));
@@ -1355,6 +1394,13 @@ PNG_EXTERN void png_check_IHDR PNGARG((png_structp png_ptr, int color_type, int interlace_type, int compression_type,
int filter_type));
+/* Added at libpng version 1.5.10 */
+#if defined(PNG_READ_CHECK_FOR_INVALID_INDEX_SUPPORTED) || \
+ defined(PNG_WRITE_CHECK_FOR_INVALID_INDEX_SUPPORTED)
+PNG_EXTERN void png_do_check_palette_indexes PNGARG((png_structp png_ptr,
+ png_row_infop row_info));
+#endif
+
/* Free all memory used by the read (old method - NOT DLL EXPORTED) */
PNG_EXTERN void png_read_destroy PNGARG((png_structp png_ptr,
png_infop info_ptr, png_infop end_info_ptr));
@@ -1536,7 +1582,7 @@ PNG_EXTERN void png_ascii_from_fixed PNGARG((png_structp png_ptr, #define PNG_FP_IS_ZERO(state) (((state) & PNG_FP_Z_MASK) == PNG_FP_SAW_DIGIT)
#define PNG_FP_IS_POSITIVE(state) (((state) & PNG_FP_NZ_MASK) == PNG_FP_Z_MASK)
#define PNG_FP_IS_NEGATIVE(state) (((state) & PNG_FP_NZ_MASK) == PNG_FP_NZ_MASK)
-
+
/* The actual parser. This can be called repeatedly, it updates
* the index into the string and the state variable (which must
* be initialzed to 0). It returns a result code, as above. There
diff --git a/plugins/AdvaImg/src/LibPNG/pngread.c b/plugins/AdvaImg/src/LibPNG/pngread.c index e2641d540f..96a2a56673 100644 --- a/plugins/AdvaImg/src/LibPNG/pngread.c +++ b/plugins/AdvaImg/src/LibPNG/pngread.c @@ -1,8 +1,8 @@ /* pngread.c - read a PNG file
*
- * Last changed in libpng 1.5.7 [December 15, 2011]
- * Copyright (c) 1998-2011 Glenn Randers-Pehrson
+ * Last changed in libpng 1.5.10 [March 8, 2012]
+ * Copyright (c) 1998-2012 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.)
*
@@ -67,15 +67,11 @@ png_create_read_struct_2,(png_const_charp user_png_ver, png_voidp error_ptr, png_ptr->user_width_max = PNG_USER_WIDTH_MAX;
png_ptr->user_height_max = PNG_USER_HEIGHT_MAX;
-# ifdef PNG_USER_CHUNK_CACHE_MAX
/* Added at libpng-1.2.43 and 1.4.0 */
png_ptr->user_chunk_cache_max = PNG_USER_CHUNK_CACHE_MAX;
-# endif
-# ifdef PNG_SET_USER_CHUNK_MALLOC_MAX
/* Added at libpng-1.2.43 and 1.4.1 */
png_ptr->user_chunk_malloc_max = PNG_USER_CHUNK_MALLOC_MAX;
-# endif
#endif
#ifdef PNG_SETJMP_SUPPORTED
@@ -805,6 +801,13 @@ png_read_end(png_structp png_ptr, png_infop info_ptr) png_crc_finish(png_ptr, 0); /* Finish off CRC from last IDAT chunk */
+#ifdef PNG_READ_CHECK_FOR_INVALID_INDEX_SUPPORTED
+ /* Report invalid palette index; added at libng-1.5.10 */
+ if (png_ptr->color_type == PNG_COLOR_TYPE_PALETTE &&
+ png_ptr->num_palette_max > png_ptr->num_palette)
+ png_benign_error(png_ptr, "Read palette index exceeding num_palette");
+#endif
+
do
{
png_uint_32 length = png_read_chunk_header(png_ptr);
@@ -1070,12 +1073,6 @@ png_read_destroy(png_structp png_ptr, png_infop info_ptr, png_free(png_ptr, png_ptr->save_buffer);
#endif
-#ifdef PNG_PROGRESSIVE_READ_SUPPORTED
-#ifdef PNG_TEXT_SUPPORTED
- png_free(png_ptr, png_ptr->current_text);
-#endif /* PNG_TEXT_SUPPORTED */
-#endif /* PNG_PROGRESSIVE_READ_SUPPORTED */
-
/* Save the important info out of the png_struct, in case it is
* being used again.
*/
diff --git a/plugins/AdvaImg/src/LibPNG/pngrtran.c b/plugins/AdvaImg/src/LibPNG/pngrtran.c index bbee10ce56..4a4049597b 100644 --- a/plugins/AdvaImg/src/LibPNG/pngrtran.c +++ b/plugins/AdvaImg/src/LibPNG/pngrtran.c @@ -1,8 +1,8 @@ /* pngrtran.c - transforms the data in a row for PNG readers
*
- * Last changed in libpng 1.5.7 [December 15, 2011]
- * Copyright (c) 1998-2011 Glenn Randers-Pehrson
+ * Last changed in libpng 1.5.11 [June 14, 2012]
+ * Copyright (c) 1998-2012 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.)
*
@@ -1770,8 +1770,8 @@ png_init_read_transformations(png_structp png_ptr) int num_palette = png_ptr->num_palette;
int i;
- /*NOTE: there are other transformations that should probably be in here
- * too.
+ /* NOTE: there are other transformations that should probably be in
+ * here too.
*/
for (i = 0; i < num_palette; i++)
{
@@ -1830,12 +1830,15 @@ png_init_read_transformations(png_structp png_ptr) #ifdef PNG_READ_SHIFT_SUPPORTED
if ((png_ptr->transformations & PNG_SHIFT) &&
+ !(png_ptr->transformations & PNG_EXPAND) &&
(png_ptr->color_type == PNG_COLOR_TYPE_PALETTE))
{
int i;
int istop = png_ptr->num_palette;
int shift = 8 - png_ptr->sig_bit.red;
+ png_ptr->transformations &= ~PNG_SHIFT;
+
/* significant bits can be in the range 1 to 7 for a meaninful result, if
* the number of significant bits is 0 then no shift is done (this is an
* error condition which is silently ignored.)
@@ -2274,7 +2277,7 @@ png_do_read_transformations(png_structp png_ptr, png_row_infop row_info) #endif
#ifdef PNG_READ_GRAY_TO_RGB_SUPPORTED
- /*NOTE: moved here in 1.5.4 (from much later in this list.) */
+ /* NOTE: moved here in 1.5.4 (from much later in this list.) */
if ((png_ptr->transformations & PNG_GRAY_TO_RGB) &&
(png_ptr->mode & PNG_BACKGROUND_IS_GRAY))
png_do_gray_to_rgb(row_info, png_ptr->row_buf + 1);
@@ -2296,6 +2299,13 @@ png_do_read_transformations(png_structp png_ptr, png_row_infop row_info) png_do_unpack(row_info, png_ptr->row_buf + 1);
#endif
+#ifdef PNG_READ_CHECK_FOR_INVALID_INDEX_SUPPORTED
+ /* Added at libpng-1.5.10 */
+ if (row_info->color_type == PNG_COLOR_TYPE_PALETTE &&
+ png_ptr->num_palette_max >= 0)
+ png_do_check_palette_indexes(png_ptr, row_info);
+#endif
+
#ifdef PNG_READ_BGR_SUPPORTED
if (png_ptr->transformations & PNG_BGR)
png_do_bgr(row_info, png_ptr->row_buf + 1);
@@ -3293,7 +3303,7 @@ png_do_rgb_to_gray(png_structp png_ptr, png_row_infop row_info, png_bytep row) if (red != green || red != blue)
{
rgb_error |= 1;
- /*NOTE: this is the historical approach which simply
+ /* NOTE: this is the historical approach which simply
* truncates the results.
*/
*(dp++) = (png_byte)((rc*red + gc*green + bc*blue)>>15);
@@ -3695,8 +3705,10 @@ png_do_compose(png_row_infop row_info, png_bytep row, png_structp png_ptr) if (v == png_ptr->trans_color.gray)
{
/* Background is already in screen gamma */
- *sp = (png_byte)((png_ptr->background.gray >> 8) & 0xff);
- *(sp + 1) = (png_byte)(png_ptr->background.gray & 0xff);
+ *sp = (png_byte)((png_ptr->background.gray >> 8)
+ & 0xff);
+ *(sp + 1) = (png_byte)(png_ptr->background.gray
+ & 0xff);
}
else
@@ -3719,8 +3731,10 @@ png_do_compose(png_row_infop row_info, png_bytep row, png_structp png_ptr) if (v == png_ptr->trans_color.gray)
{
- *sp = (png_byte)((png_ptr->background.gray >> 8) & 0xff);
- *(sp + 1) = (png_byte)(png_ptr->background.gray & 0xff);
+ *sp = (png_byte)((png_ptr->background.gray >> 8)
+ & 0xff);
+ *(sp + 1) = (png_byte)(png_ptr->background.gray
+ & 0xff);
}
}
}
@@ -3800,9 +3814,12 @@ png_do_compose(png_row_infop row_info, png_bytep row, png_structp png_ptr) /* Background is already in screen gamma */
*sp = (png_byte)((png_ptr->background.red >> 8) & 0xff);
*(sp + 1) = (png_byte)(png_ptr->background.red & 0xff);
- *(sp + 2) = (png_byte)((png_ptr->background.green >> 8) & 0xff);
- *(sp + 3) = (png_byte)(png_ptr->background.green & 0xff);
- *(sp + 4) = (png_byte)((png_ptr->background.blue >> 8) & 0xff);
+ *(sp + 2) = (png_byte)((png_ptr->background.green >> 8)
+ & 0xff);
+ *(sp + 3) = (png_byte)(png_ptr->background.green
+ & 0xff);
+ *(sp + 4) = (png_byte)((png_ptr->background.blue >> 8)
+ & 0xff);
*(sp + 5) = (png_byte)(png_ptr->background.blue & 0xff);
}
@@ -3843,9 +3860,12 @@ png_do_compose(png_row_infop row_info, png_bytep row, png_structp png_ptr) {
*sp = (png_byte)((png_ptr->background.red >> 8) & 0xff);
*(sp + 1) = (png_byte)(png_ptr->background.red & 0xff);
- *(sp + 2) = (png_byte)((png_ptr->background.green >> 8) & 0xff);
- *(sp + 3) = (png_byte)(png_ptr->background.green & 0xff);
- *(sp + 4) = (png_byte)((png_ptr->background.blue >> 8) & 0xff);
+ *(sp + 2) = (png_byte)((png_ptr->background.green >> 8)
+ & 0xff);
+ *(sp + 3) = (png_byte)(png_ptr->background.green
+ & 0xff);
+ *(sp + 4) = (png_byte)((png_ptr->background.blue >> 8)
+ & 0xff);
*(sp + 5) = (png_byte)(png_ptr->background.blue & 0xff);
}
}
@@ -3928,7 +3948,8 @@ png_do_compose(png_row_infop row_info, png_bytep row, png_structp png_ptr) else if (a == 0)
{
/* Background is already in screen gamma */
- *sp = (png_byte)((png_ptr->background.gray >> 8) & 0xff);
+ *sp = (png_byte)((png_ptr->background.gray >> 8)
+ & 0xff);
*(sp + 1) = (png_byte)(png_ptr->background.gray & 0xff);
}
@@ -3958,7 +3979,8 @@ png_do_compose(png_row_infop row_info, png_bytep row, png_structp png_ptr) if (a == 0)
{
- *sp = (png_byte)((png_ptr->background.gray >> 8) & 0xff);
+ *sp = (png_byte)((png_ptr->background.gray >> 8)
+ & 0xff);
*(sp + 1) = (png_byte)(png_ptr->background.gray & 0xff);
}
@@ -4088,9 +4110,12 @@ png_do_compose(png_row_infop row_info, png_bytep row, png_structp png_ptr) /* Background is already in screen gamma */
*sp = (png_byte)((png_ptr->background.red >> 8) & 0xff);
*(sp + 1) = (png_byte)(png_ptr->background.red & 0xff);
- *(sp + 2) = (png_byte)((png_ptr->background.green >> 8) & 0xff);
- *(sp + 3) = (png_byte)(png_ptr->background.green & 0xff);
- *(sp + 4) = (png_byte)((png_ptr->background.blue >> 8) & 0xff);
+ *(sp + 2) = (png_byte)((png_ptr->background.green >> 8)
+ & 0xff);
+ *(sp + 3) = (png_byte)(png_ptr->background.green
+ & 0xff);
+ *(sp + 4) = (png_byte)((png_ptr->background.blue >> 8)
+ & 0xff);
*(sp + 5) = (png_byte)(png_ptr->background.blue & 0xff);
}
@@ -4101,14 +4126,16 @@ png_do_compose(png_row_infop row_info, png_bytep row, png_structp png_ptr) v = gamma_16_to_1[*(sp + 1) >> gamma_shift][*sp];
png_composite_16(w, v, a, png_ptr->background_1.red);
if (!optimize)
- w = gamma_16_from_1[((w&0xff) >> gamma_shift)][w >> 8];
+ w = gamma_16_from_1[((w&0xff) >> gamma_shift)]
+ [w >> 8];
*sp = (png_byte)((w >> 8) & 0xff);
*(sp + 1) = (png_byte)(w & 0xff);
v = gamma_16_to_1[*(sp + 3) >> gamma_shift][*(sp + 2)];
png_composite_16(w, v, a, png_ptr->background_1.green);
if (!optimize)
- w = gamma_16_from_1[((w&0xff) >> gamma_shift)][w >> 8];
+ w = gamma_16_from_1[((w&0xff) >> gamma_shift)]
+ [w >> 8];
*(sp + 2) = (png_byte)((w >> 8) & 0xff);
*(sp + 3) = (png_byte)(w & 0xff);
@@ -4116,7 +4143,8 @@ png_do_compose(png_row_infop row_info, png_bytep row, png_structp png_ptr) v = gamma_16_to_1[*(sp + 5) >> gamma_shift][*(sp + 4)];
png_composite_16(w, v, a, png_ptr->background_1.blue);
if (!optimize)
- w = gamma_16_from_1[((w&0xff) >> gamma_shift)][w >> 8];
+ w = gamma_16_from_1[((w&0xff) >> gamma_shift)]
+ [w >> 8];
*(sp + 4) = (png_byte)((w >> 8) & 0xff);
*(sp + 5) = (png_byte)(w & 0xff);
@@ -4137,9 +4165,12 @@ png_do_compose(png_row_infop row_info, png_bytep row, png_structp png_ptr) {
*sp = (png_byte)((png_ptr->background.red >> 8) & 0xff);
*(sp + 1) = (png_byte)(png_ptr->background.red & 0xff);
- *(sp + 2) = (png_byte)((png_ptr->background.green >> 8) & 0xff);
- *(sp + 3) = (png_byte)(png_ptr->background.green & 0xff);
- *(sp + 4) = (png_byte)((png_ptr->background.blue >> 8) & 0xff);
+ *(sp + 2) = (png_byte)((png_ptr->background.green >> 8)
+ & 0xff);
+ *(sp + 3) = (png_byte)(png_ptr->background.green
+ & 0xff);
+ *(sp + 4) = (png_byte)((png_ptr->background.blue >> 8)
+ & 0xff);
*(sp + 5) = (png_byte)(png_ptr->background.blue & 0xff);
}
@@ -4331,7 +4362,7 @@ png_do_gamma(png_row_infop row_info, png_bytep row, png_structp png_ptr) ((((int)gamma_table[a|(a>>2)|(a>>4)|(a>>6)]) ) & 0xc0)|
((((int)gamma_table[(b<<2)|b|(b>>2)|(b>>4)])>>2) & 0x30)|
((((int)gamma_table[(c<<4)|(c<<2)|c|(c>>2)])>>4) & 0x0c)|
- ((((int)gamma_table[(d<<6)|(d<<4)|(d<<2)|d])>>6)));
+ ((((int)gamma_table[(d<<6)|(d<<4)|(d<<2)|d])>>6) ));
sp++;
}
}
diff --git a/plugins/AdvaImg/src/LibPNG/pngrutil.c b/plugins/AdvaImg/src/LibPNG/pngrutil.c index 995896dbc5..b9c3905c79 100644 --- a/plugins/AdvaImg/src/LibPNG/pngrutil.c +++ b/plugins/AdvaImg/src/LibPNG/pngrutil.c @@ -1,7 +1,7 @@ /* pngrutil.c - utilities to read a PNG file
*
- * Last changed in libpng 1.5.9 [February 18, 2012]
+ * Last changed in libpng 1.5.10 [March 8, 2012]
* Copyright (c) 1998-2012 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.)
@@ -434,14 +434,12 @@ png_decompress_chunk(png_structp png_ptr, int comp_type, */
if (prefix_size >= (~(png_size_t)0) - 1 ||
expanded_size >= (~(png_size_t)0) - 1 - prefix_size
-#ifdef PNG_SET_CHUNK_MALLOC_LIMIT_SUPPORTED
+#ifdef PNG_USER_LIMITS_SUPPORTED
|| (png_ptr->user_chunk_malloc_max &&
(prefix_size + expanded_size >= png_ptr->user_chunk_malloc_max - 1))
#else
-# ifdef PNG_USER_CHUNK_MALLOC_MAX
|| ((PNG_USER_CHUNK_MALLOC_MAX > 0) &&
prefix_size + expanded_size >= PNG_USER_CHUNK_MALLOC_MAX - 1)
-# endif
#endif
)
png_warning(png_ptr, "Exceeded size limit while expanding chunk");
@@ -1259,13 +1257,16 @@ png_handle_iCCP(png_structp png_ptr, png_infop info_ptr, png_uint_32 length) /* Should be an error, but we can cope with it */
png_warning(png_ptr, "Out of place iCCP chunk");
- if (info_ptr != NULL && (info_ptr->valid & PNG_INFO_iCCP))
+ if ((png_ptr->mode & PNG_HAVE_iCCP) || (info_ptr != NULL &&
+ (info_ptr->valid & (PNG_INFO_iCCP|PNG_INFO_sRGB))))
{
png_warning(png_ptr, "Duplicate iCCP chunk");
png_crc_finish(png_ptr, length);
return;
}
+ png_ptr->mode |= PNG_HAVE_iCCP;
+
#ifdef PNG_MAX_MALLOC_64K
if (length > (png_uint_32)65535L)
{
@@ -1795,16 +1796,16 @@ png_handle_hIST(png_structp png_ptr, png_infop info_ptr, png_uint_32 length) return;
}
- num = length / 2 ;
-
- if (num != (unsigned int)png_ptr->num_palette || num >
- (unsigned int)PNG_MAX_PALETTE_LENGTH)
+ if (length > 2*PNG_MAX_PALETTE_LENGTH ||
+ length != (unsigned int) (2*png_ptr->num_palette))
{
png_warning(png_ptr, "Incorrect hIST chunk length");
png_crc_finish(png_ptr, length);
return;
}
+ num = length / 2 ;
+
for (i = 0; i < num; i++)
{
png_byte buf[2];
@@ -3115,7 +3116,7 @@ png_combine_row(png_structp png_ptr, png_bytep dp, int display) /* This can only be the RGB case, so each copy is exactly one
* pixel and it is not necessary to check for a partial copy.
*/
- for (;;)
+ for(;;)
{
dp[0] = sp[0], dp[1] = sp[1], dp[2] = sp[2];
@@ -3705,7 +3706,7 @@ png_init_filter_functions_neon(png_structp pp, unsigned int bpp) {
pp->read_filter[PNG_FILTER_VALUE_SUB-1] = png_read_filter_row_sub3_neon;
pp->read_filter[PNG_FILTER_VALUE_AVG-1] = png_read_filter_row_avg3_neon;
- pp->read_filter[PNG_FILTER_VALUE_PAETH-1] =
+ pp->read_filter[PNG_FILTER_VALUE_PAETH-1] =
png_read_filter_row_paeth3_neon;
}
diff --git a/plugins/AdvaImg/src/LibPNG/pngset.c b/plugins/AdvaImg/src/LibPNG/pngset.c index e753ca8867..fc99f5fdb6 100644 --- a/plugins/AdvaImg/src/LibPNG/pngset.c +++ b/plugins/AdvaImg/src/LibPNG/pngset.c @@ -1,8 +1,8 @@ /* pngset.c - storage of image information into info struct
*
- * Last changed in libpng 1.5.7 [December 15, 2011]
- * Copyright (c) 1998-2011 Glenn Randers-Pehrson
+ * Last changed in libpng 1.5.11 [June 14, 2012]
+ * Copyright (c) 1998-2012 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.)
*
@@ -149,7 +149,7 @@ png_set_gAMA_fixed(png_structp png_ptr, png_infop info_ptr, png_fixed_point * possible for 1/gamma to overflow the limit of 21474 and this means the
* gamma value must be at least 5/100000 and hence at most 20000.0. For
* safety the limits here are a little narrower. The values are 0.00016 to
- * 6250.0, which are truly ridiculous gammma values (and will produce
+ * 6250.0, which are truly ridiculous gamma values (and will produce
* displays that are all black or all white.)
*/
if (file_gamma < 16 || file_gamma > 625000000)
@@ -692,24 +692,28 @@ png_set_text_2(png_structp png_ptr, png_infop info_ptr, */
if (info_ptr->num_text + num_text > info_ptr->max_text)
{
+ int old_max_text = info_ptr->max_text;
+ int old_num_text = info_ptr->num_text;
+
if (info_ptr->text != NULL)
{
png_textp old_text;
- int old_max;
- old_max = info_ptr->max_text;
info_ptr->max_text = info_ptr->num_text + num_text + 8;
old_text = info_ptr->text;
+
info_ptr->text = (png_textp)png_malloc_warn(png_ptr,
(png_size_t)(info_ptr->max_text * png_sizeof(png_text)));
if (info_ptr->text == NULL)
{
- png_free(png_ptr, old_text);
+ /* Restore to previous condition */
+ info_ptr->max_text = old_max_text;
+ info_ptr->text = old_text;
return(1);
}
- png_memcpy(info_ptr->text, old_text, (png_size_t)(old_max *
+ png_memcpy(info_ptr->text, old_text, (png_size_t)(old_max_text *
png_sizeof(png_text)));
png_free(png_ptr, old_text);
}
@@ -721,7 +725,12 @@ png_set_text_2(png_structp png_ptr, png_infop info_ptr, info_ptr->text = (png_textp)png_malloc_warn(png_ptr,
(png_size_t)(info_ptr->max_text * png_sizeof(png_text)));
if (info_ptr->text == NULL)
+ {
+ /* Restore to previous condition */
+ info_ptr->num_text = old_num_text;
+ info_ptr->max_text = old_max_text;
return(1);
+ }
info_ptr->free_me |= PNG_FREE_TEXT;
}
@@ -1281,4 +1290,22 @@ png_set_benign_errors(png_structp png_ptr, int allowed) png_ptr->flags &= ~PNG_FLAG_BENIGN_ERRORS_WARN;
}
#endif /* PNG_BENIGN_ERRORS_SUPPORTED */
+
+#ifdef PNG_CHECK_FOR_INVALID_INDEX_SUPPORTED
+/* Whether to report invalid palette index; added at libng-1.5.10
+ * allowed - one of 0: disable; 1: enable
+ */
+void PNGAPI
+png_set_check_for_invalid_index(png_structp png_ptr, int allowed)
+{
+ png_debug(1, "in png_set_check_for_invalid_index");
+
+ if (allowed)
+ png_ptr->num_palette_max = 0;
+
+ else
+ png_ptr->num_palette_max = -1;
+}
+#endif
+
#endif /* PNG_READ_SUPPORTED || PNG_WRITE_SUPPORTED */
diff --git a/plugins/AdvaImg/src/LibPNG/pngstruct.h b/plugins/AdvaImg/src/LibPNG/pngstruct.h index 1824c49114..73d71149ee 100644 --- a/plugins/AdvaImg/src/LibPNG/pngstruct.h +++ b/plugins/AdvaImg/src/LibPNG/pngstruct.h @@ -1,7 +1,7 @@ /* pngstruct.h - header file for PNG reference library
*
- * Copyright (c) 1998-2011 Glenn Randers-Pehrson
+ * Copyright (c) 1998-2012 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.)
*
@@ -121,6 +121,12 @@ struct png_struct_def png_uint_32 crc; /* current chunk CRC value */
png_colorp palette; /* palette from the input file */
png_uint_16 num_palette; /* number of color entries in palette */
+
+/* Added at libpng-1.5.10 */
+#ifdef PNG_CHECK_FOR_INVALID_INDEX_SUPPORTED
+ int num_palette_max; /* maximum palette index found in IDAT */
+#endif
+
png_uint_16 num_trans; /* number of transparency values */
png_byte compression; /* file compression type (always 0) */
png_byte filter; /* file filter type (always 0) */
@@ -211,13 +217,6 @@ struct png_struct_def int process_mode; /* what push library is currently doing */
int cur_palette; /* current push library palette index */
-# ifdef PNG_TEXT_SUPPORTED
- png_size_t current_text_size; /* current size of text input data */
- png_size_t current_text_left; /* how much text left to read in input */
- png_charp current_text; /* current text chunk buffer */
- png_charp current_text_ptr; /* current location in current_text */
-# endif /* PNG_PROGRESSIVE_READ_SUPPORTED && PNG_TEXT_SUPPORTED */
-
#endif /* PNG_PROGRESSIVE_READ_SUPPORTED */
#if defined(__TURBOC__) && !defined(_Windows) && !defined(__FLAT__)
@@ -249,6 +248,7 @@ struct png_struct_def #endif
#ifdef PNG_TIME_RFC1123_SUPPORTED
+ /* This is going to be unused in libpng16 and removed from libpng17 */
char time_buffer[29]; /* String to hold RFC 1123 time text */
#endif
diff --git a/plugins/AdvaImg/src/LibPNG/pngtest.c b/plugins/AdvaImg/src/LibPNG/pngtest.c index 840517400b..5594333568 100644 --- a/plugins/AdvaImg/src/LibPNG/pngtest.c +++ b/plugins/AdvaImg/src/LibPNG/pngtest.c @@ -1817,4 +1817,4 @@ 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_9 Your_png_h_is_not_version_1_5_9;
+typedef png_libpng_version_1_5_13 Your_png_h_is_not_version_1_5_13;
diff --git a/plugins/AdvaImg/src/LibPNG/pngtrans.c b/plugins/AdvaImg/src/LibPNG/pngtrans.c index 53d9a25b95..d562eb061c 100644 --- a/plugins/AdvaImg/src/LibPNG/pngtrans.c +++ b/plugins/AdvaImg/src/LibPNG/pngtrans.c @@ -1,8 +1,8 @@ /* pngtrans.c - transforms the data in a row (used by both readers and writers)
*
- * Last changed in libpng 1.5.4 [July 7, 2011]
- * Copyright (c) 1998-2011 Glenn Randers-Pehrson
+ * Last changed in libpng 1.5.11 [June 14, 2012]
+ * Copyright (c) 1998-2012 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.)
*
@@ -619,6 +619,109 @@ png_do_bgr(png_row_infop row_info, png_bytep row) }
#endif /* PNG_READ_BGR_SUPPORTED or PNG_WRITE_BGR_SUPPORTED */
+#if defined(PNG_READ_CHECK_FOR_INVALID_INDEX_SUPPORTED) || \
+ defined(PNG_WRITE_CHECK_FOR_INVALID_INDEX_SUPPORTED)
+/* Added at libpng-1.5.10 */
+void /* PRIVATE */
+png_do_check_palette_indexes(png_structp png_ptr, png_row_infop row_info)
+{
+ if (png_ptr->num_palette < (1 << row_info->bit_depth) &&
+ png_ptr->num_palette > 0) /* num_palette can be 0 in MNG files */
+ {
+ /* Calculations moved outside switch in an attempt to stop different
+ * compiler warnings. 'padding' is in *bits* within the last byte, it is
+ * an 'int' because pixel_depth becomes an 'int' in the expression below,
+ * and this calculation is used because it avoids warnings that other
+ * forms produced on either GCC or MSVC.
+ */
+ int padding = (-row_info->pixel_depth * row_info->width) & 7;
+ png_bytep rp = png_ptr->row_buf + row_info->rowbytes;
+
+ switch (row_info->bit_depth)
+ {
+ case 1:
+ {
+ /* in this case, all bytes must be 0 so we don't need
+ * to unpack the pixels except for the rightmost one.
+ */
+ for (; rp > png_ptr->row_buf; rp--)
+ {
+ if (*rp >> padding != 0)
+ png_ptr->num_palette_max = 1;
+ padding = 0;
+ }
+
+ break;
+ }
+
+ case 2:
+ {
+ for (; rp > png_ptr->row_buf; rp--)
+ {
+ int i = ((*rp >> padding) & 0x03);
+
+ if (i > png_ptr->num_palette_max)
+ png_ptr->num_palette_max = i;
+
+ i = (((*rp >> padding) >> 2) & 0x03);
+
+ if (i > png_ptr->num_palette_max)
+ png_ptr->num_palette_max = i;
+
+ i = (((*rp >> padding) >> 4) & 0x03);
+
+ if (i > png_ptr->num_palette_max)
+ png_ptr->num_palette_max = i;
+
+ i = (((*rp >> padding) >> 6) & 0x03);
+
+ if (i > png_ptr->num_palette_max)
+ png_ptr->num_palette_max = i;
+
+ padding = 0;
+ }
+
+ break;
+ }
+
+ case 4:
+ {
+ for (; rp > png_ptr->row_buf; rp--)
+ {
+ int i = ((*rp >> padding) & 0x0f);
+
+ if (i > png_ptr->num_palette_max)
+ png_ptr->num_palette_max = i;
+
+ i = (((*rp >> padding) >> 4) & 0x0f);
+
+ if (i > png_ptr->num_palette_max)
+ png_ptr->num_palette_max = i;
+
+ padding = 0;
+ }
+
+ break;
+ }
+
+ case 8:
+ {
+ for (; rp > png_ptr->row_buf; rp--)
+ {
+ if (*rp > png_ptr->num_palette_max)
+ png_ptr->num_palette_max = (int) *rp;
+ }
+
+ break;
+ }
+
+ default:
+ break;
+ }
+ }
+}
+#endif /* PNG_CHECK_FOR_INVALID_INDEX_SUPPORTED */
+
#if defined(PNG_READ_USER_TRANSFORM_SUPPORTED) || \
defined(PNG_WRITE_USER_TRANSFORM_SUPPORTED)
#ifdef PNG_USER_TRANSFORM_PTR_SUPPORTED
diff --git a/plugins/AdvaImg/src/LibPNG/pngwrite.c b/plugins/AdvaImg/src/LibPNG/pngwrite.c index dc12a20481..c188439759 100644 --- a/plugins/AdvaImg/src/LibPNG/pngwrite.c +++ b/plugins/AdvaImg/src/LibPNG/pngwrite.c @@ -1,8 +1,8 @@ /* pngwrite.c - general routines to write a PNG file
*
- * Last changed in libpng 1.5.7 [December 15, 2011]
- * Copyright (c) 1998-2011 Glenn Randers-Pehrson
+ * Last changed in libpng 1.5.11 [June 14, 2012]
+ * Copyright (c) 1998-2012 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.)
*
@@ -305,6 +305,11 @@ png_write_end(png_structp png_ptr, png_infop info_ptr) if (!(png_ptr->mode & PNG_HAVE_IDAT))
png_error(png_ptr, "No IDATs written into file");
+#ifdef PNG_WRITE_CHECK_FOR_INVALID_INDEX_SUPPORTED
+ if (png_ptr->num_palette_max > png_ptr->num_palette)
+ png_benign_error(png_ptr, "Wrote palette index exceeding num_palette");
+#endif
+
/* See if user wants us to write information chunks */
if (info_ptr != NULL)
{
@@ -798,6 +803,14 @@ png_write_row(png_structp png_ptr, png_const_bytep row) }
#endif
+/* Added at libpng-1.5.10 */
+#ifdef PNG_WRITE_CHECK_FOR_INVALID_INDEX_SUPPORTED
+ /* Check for out-of-range palette index */
+ if (row_info.color_type == PNG_COLOR_TYPE_PALETTE &&
+ png_ptr->num_palette_max >= 0)
+ png_do_check_palette_indexes(png_ptr, &row_info);
+#endif
+
/* Find a filter if necessary, filter the row and write it out. */
png_write_find_filter(png_ptr, &row_info);
diff --git a/plugins/AdvaImg/src/LibPNG/pngwtran.c b/plugins/AdvaImg/src/LibPNG/pngwtran.c index b598149a96..e962b68353 100644 --- a/plugins/AdvaImg/src/LibPNG/pngwtran.c +++ b/plugins/AdvaImg/src/LibPNG/pngwtran.c @@ -1,8 +1,8 @@ /* pngwtran.c - transforms the data in a row for PNG writers
*
- * Last changed in libpng 1.5.6 [November 3, 2011]
- * Copyright (c) 1998-2011 Glenn Randers-Pehrson
+ * Last changed in libpng 1.5.13 [September 27, 2012]
+ * Copyright (c) 1998-2012 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.)
*
@@ -45,8 +45,20 @@ png_do_write_transformations(png_structp png_ptr, png_row_infop row_info) #ifdef PNG_WRITE_FILLER_SUPPORTED
if (png_ptr->transformations & PNG_FILLER)
- png_do_strip_channel(row_info, png_ptr->row_buf + 1,
- !(png_ptr->flags & PNG_FLAG_FILLER_AFTER));
+ {
+ if (png_ptr->color_type & (PNG_COLOR_MASK_ALPHA|PNG_COLOR_MASK_PALETTE))
+ {
+ /* GA, RGBA or palette; in any of these cases libpng will not do the
+ * the correct thing (whatever that might be).
+ */
+ png_warning(png_ptr, "incorrect png_set_filler call ignored");
+ png_ptr->transformations &= ~PNG_FILLER;
+ }
+
+ else
+ png_do_strip_channel(row_info, png_ptr->row_buf + 1,
+ !(png_ptr->flags & PNG_FLAG_FILLER_AFTER));
+ }
#endif
#ifdef PNG_WRITE_PACKSWAP_SUPPORTED
diff --git a/plugins/AdvaImg/src/LibPNG/pngwutil.c b/plugins/AdvaImg/src/LibPNG/pngwutil.c index 64888f7c6c..3cef5b295d 100644 --- a/plugins/AdvaImg/src/LibPNG/pngwutil.c +++ b/plugins/AdvaImg/src/LibPNG/pngwutil.c @@ -1,8 +1,8 @@ /* pngwutil.c - utilities to write a PNG file
*
- * Last changed in libpng 1.5.6 [November 3, 2011]
- * Copyright (c) 1998-2011 Glenn Randers-Pehrson
+ * Last changed in libpng 1.5.10 [March 8, 2012]
+ * Copyright (c) 1998-2012 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.)
*
@@ -569,14 +569,15 @@ png_text_compress(png_structp png_ptr, /* Ship the compressed text out via chunk writes */
static void /* PRIVATE */
-png_write_compressed_data_out(png_structp png_ptr, compression_state *comp)
+png_write_compressed_data_out(png_structp png_ptr, compression_state *comp,
+ png_size_t data_len)
{
int i;
/* Handle the no-compression case */
if (comp->input)
{
- png_write_chunk_data(png_ptr, comp->input, comp->input_len);
+ png_write_chunk_data(png_ptr, comp->input, data_len);
return;
}
@@ -585,7 +586,7 @@ png_write_compressed_data_out(png_structp png_ptr, compression_state *comp) /* The zbuf_size test is because the code below doesn't work if zbuf_size is
* '1'; simply skip it to avoid memory overwrite.
*/
- if (comp->input_len >= 2 && comp->input_len < 16384 && png_ptr->zbuf_size > 1)
+ if (data_len >= 2 && comp->input_len < 16384 && png_ptr->zbuf_size > 1)
{
unsigned int z_cmf; /* zlib compression method and flags */
@@ -1164,8 +1165,7 @@ png_write_iCCP(png_structp png_ptr, png_const_charp name, int compression_type, if (profile_len)
{
- comp.input_len = profile_len;
- png_write_compressed_data_out(png_ptr, &comp);
+ png_write_compressed_data_out(png_ptr, &comp, profile_len);
}
png_write_chunk_end(png_ptr);
@@ -1370,7 +1370,8 @@ png_write_tRNS(png_structp png_ptr, png_const_bytep trans_alpha, }
/* Write the chunk out as it is */
- png_write_complete_chunk(png_ptr, png_tRNS, trans_alpha, (png_size_t)num_trans);
+ png_write_complete_chunk(png_ptr, png_tRNS, trans_alpha,
+ (png_size_t)num_trans);
}
else if (color_type == PNG_COLOR_TYPE_GRAY)
@@ -1735,8 +1736,7 @@ png_write_zTXt(png_structp png_ptr, png_const_charp key, png_const_charp text, png_write_chunk_data(png_ptr, &buf, (png_size_t)1);
/* Write the compressed data */
- comp.input_len = text_len;
- png_write_compressed_data_out(png_ptr, &comp);
+ png_write_compressed_data_out(png_ptr, &comp, text_len);
/* Close the chunk */
png_write_chunk_end(png_ptr);
@@ -1827,7 +1827,7 @@ png_write_iTXt(png_structp png_ptr, int compression, png_const_charp key, png_write_chunk_data(png_ptr, (lang_key ? (png_const_bytep)lang_key : cbuf),
(png_size_t)(lang_key_len + 1));
- png_write_compressed_data_out(png_ptr, &comp);
+ png_write_compressed_data_out(png_ptr, &comp, text_len);
png_write_chunk_end(png_ptr);
|