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diff --git a/png/README b/png/README deleted file mode 100755 index dc6c00b..0000000 --- a/png/README +++ /dev/null @@ -1,202 +0,0 @@ -README for libpng version 1.6.12 - June 12, 2014 (shared library 16.0) -See the note about version numbers near the top of png.h - -See INSTALL for instructions on how to install libpng. - -Libpng comes in several distribution formats. Get libpng-*.tar.gz or -libpng-*.tar.xz or if you want UNIX-style line endings in the text files, -or lpng*.7z or lpng*.zip if you want DOS-style line endings. - -Version 0.89 was the first official release of libpng. Don't let the -fact that it's the first release fool you. The libpng library has been in -extensive use and testing since mid-1995. By late 1997 it had -finally gotten to the stage where there hadn't been significant -changes to the API in some time, and people have a bad feeling about -libraries with versions < 1.0. Version 1.0.0 was released in -March 1998. - -**** -Note that some of the changes to the png_info structure render this -version of the library binary incompatible with libpng-0.89 or -earlier versions if you are using a shared library. The type of the -"filler" parameter for png_set_filler() has changed from png_byte to -png_uint_32, which will affect shared-library applications that use -this function. - -To avoid problems with changes to the internals of png_info_struct, -new APIs have been made available in 0.95 to avoid direct application -access to info_ptr. These functions are the png_set_<chunk> and -png_get_<chunk> functions. These functions should be used when -accessing/storing the info_struct data, rather than manipulating it -directly, to avoid such problems in the future. - -It is important to note that the APIs do not make current programs -that access the info struct directly incompatible with the new -library. However, it is strongly suggested that new programs use -the new APIs (as shown in example.c and pngtest.c), and older programs -be converted to the new format, to facilitate upgrades in the future. -**** - -Additions since 0.90 include the ability to compile libpng as a -Windows DLL, and new APIs for accessing data in the info struct. -Experimental functions include the ability to set weighting and cost -factors for row filter selection, direct reads of integers from buffers -on big-endian processors that support misaligned data access, faster -methods of doing alpha composition, and more accurate 16->8 bit color -conversion. - -The additions since 0.89 include the ability to read from a PNG stream -which has had some (or all) of the signature bytes read by the calling -application. This also allows the reading of embedded PNG streams that -do not have the PNG file signature. As well, it is now possible to set -the library action on the detection of chunk CRC errors. It is possible -to set different actions based on whether the CRC error occurred in a -critical or an ancillary chunk. - -The changes made to the library, and bugs fixed are based on discussions -on the PNG-implement mailing list and not on material submitted -privately to Guy, Andreas, or Glenn. They will forward any good -suggestions to the list. - -For a detailed description on using libpng, read libpng-manual.txt. For -examples of libpng in a program, see example.c and pngtest.c. For usage -information and restrictions (what little they are) on libpng, see -png.h. For a description on using zlib (the compression library used by -libpng) and zlib's restrictions, see zlib.h - -I have included a general makefile, as well as several machine and -compiler specific ones, but you may have to modify one for your own needs. - -You should use zlib 1.0.4 or later to run this, but it MAY work with -versions as old as zlib 0.95. Even so, there are bugs in older zlib -versions which can cause the output of invalid compression streams for -some images. You will definitely need zlib 1.0.4 or later if you are -taking advantage of the MS-DOS "far" structure allocation for the small -and medium memory models. You should also note that zlib is a -compression library that is useful for more things than just PNG files. -You can use zlib as a drop-in replacement for fread() and fwrite() if -you are so inclined. - -zlib should be available at the same place that libpng is, or at zlib.net. - -You may also want a copy of the PNG specification. It is available -as an RFC, a W3C Recommendation, and an ISO/IEC Standard. You can find -these at http://www.libpng.org/pub/png/documents/ - -This code is currently being archived at libpng.sf.net in the -[DOWNLOAD] area, and at ftp://ftp.simplesystems.org. If you can't find it -in any of those places, e-mail me, and I'll help you find it. - -If you have any code changes, requests, problems, etc., please e-mail -them to me. Also, I'd appreciate any make files or project files, -and any modifications you needed to make to get libpng to compile, -along with a #define variable to tell what compiler/system you are on. -If you needed to add transformations to libpng, or wish libpng would -provide the image in a different way, drop me a note (and code, if -possible), so I can consider supporting the transformation. -Finally, if you get any warning messages when compiling libpng -(note: not zlib), and they are easy to fix, I'd appreciate the -fix. Please mention "libpng" somewhere in the subject line. Thanks. - -This release was created and will be supported by myself (of course -based in a large way on Guy's and Andreas' earlier work), and the PNG -development group. - -Send comments/corrections/commendations to png-mng-implement at -lists.sourceforge.net (subscription required; visit -https://lists.sourceforge.net/lists/listinfo/png-mng-implement -to subscribe) or to glennrp at users.sourceforge.net - -You can't reach Guy, the original libpng author, at the addresses -given in previous versions of this document. He and Andreas will -read mail addressed to the png-implement list, however. - -Please do not send general questions about PNG. Send them to -png-mng-misc at lists.sf.net (subscription required; visit -https://lists.sourceforge.net/lists/listinfo/png-mng-misc to -subscribe). If you have a question about something -in the PNG specification that is related to using libpng, send it -to me. Send me any questions that start with "I was using libpng, -and ...". If in doubt, send questions to me. I'll bounce them -to others, if necessary. - -Please do not send suggestions on how to change PNG. We have -been discussing PNG for nineteen years now, and it is official and -finished. If you have suggestions for libpng, however, I'll -gladly listen. Even if your suggestion is not used immediately, -it may be used later. - -Files in this distribution: - - ANNOUNCE => Announcement of this version, with recent changes - CHANGES => Description of changes between libpng versions - KNOWNBUG => List of known bugs and deficiencies - LICENSE => License to use and redistribute libpng - README => This file - TODO => Things not implemented in the current library - Y2KINFO => Statement of Y2K compliance - example.c => Example code for using libpng functions - libpng.3 => manual page for libpng (includes libpng-manual.txt) - libpng-manual.txt => Description of libpng and its functions - libpngpf.3 => manual page for libpng's private functions - png.5 => manual page for the PNG format - png.c => Basic interface functions common to library - png.h => Library function and interface declarations (public) - pngpriv.h => Library function and interface declarations (private) - pngconf.h => System specific library configuration (public) - pngstruct.h => png_struct declaration (private) - pnginfo.h => png_info struct declaration (private) - pngdebug.h => debugging macros (private) - pngerror.c => Error/warning message I/O functions - pngget.c => Functions for retrieving info from struct - pngmem.c => Memory handling functions - pngbar.png => PNG logo, 88x31 - pngnow.png => PNG logo, 98x31 - pngpread.c => Progressive reading functions - pngread.c => Read data/helper high-level functions - pngrio.c => Lowest-level data read I/O functions - pngrtran.c => Read data transformation functions - pngrutil.c => Read data utility functions - pngset.c => Functions for storing data into the info_struct - pngtest.c => Library test program - pngtest.png => Library test sample image - pngtrans.c => Common data transformation functions - pngwio.c => Lowest-level write I/O functions - pngwrite.c => High-level write functions - pngwtran.c => Write data transformations - pngwutil.c => Write utility functions - arm => Contains optimized code for the ARM platform - contrib => Contributions - examples => Example programs - gregbook => source code for PNG reading and writing, from - Greg Roelofs' "PNG: The Definitive Guide", - O'Reilly, 1999 - libtests => Test programs - pngminim => Minimal decoder, encoder, and progressive decoder - programs demonstrating use of pngusr.dfa - pngminus => Simple pnm2png and png2pnm programs - pngsuite => Test images - tools => Various tools - visupng => Contains a MSVC workspace for VisualPng - projects => Contains project files and workspaces for - building a DLL - owatcom => Contains a WATCOM project for building libpng - visualc71 => Contains a Microsoft Visual C++ (MSVC) - workspace for building libpng and zlib - vstudio => Contains a Microsoft Visual C++ (MSVC) - workspace for building libpng and zlib - scripts => Directory containing scripts for building libpng: - (see scripts/README.txt for the list of scripts) - -Good luck, and happy coding. - --Glenn Randers-Pehrson (current maintainer, since 1998) - Internet: glennrp at users.sourceforge.net - --Andreas Eric Dilger (former maintainer, 1996-1997) - Internet: adilger at enel.ucalgary.ca - Web: http://www-mddsp.enel.ucalgary.ca/People/adilger/ - --Guy Eric Schalnat (original author and former maintainer, 1995-1996) - (formerly of Group 42, Inc) - Internet: gschal at infinet.com |