Installing libpng version 1.2.57 - December 29, 2016 On Unix/Linux and similar systems, you can simply type ./configure [--prefix=/path] make check make install and ignore the rest of this document. If configure does not work on your system and you have a reasonably up-to-date set of tools, running ./autogen.sh before running ./configure may fix the problem. You can also run the individual commands in autogen.sh with the --force option, if supported by your version of the tools. If you run 'libtoolize --force', though, this will replace the distributed, patched, version of ltmain.sh with an unpatched version and your shared library builds may fail to produce libraries with the correct version numbers. Instead, you can use one of the custom-built makefiles in the "scripts" directory cp scripts/makefile.system makefile make test make install The files that are presently available in the scripts directory are listed and described in scripts/README.txt. Or you can use one of the "projects" in the "projects" directory. Before installing libpng, you must first install zlib, if it is not already on your system. zlib can usually be found wherever you got libpng. zlib can be placed in another directory, at the same level as libpng. If you want to use "cmake" (see www.cmake.org), type cmake . -DCMAKE_INSTALL_PREFIX=/path make make install If your system already has a preinstalled zlib you will still need to have access to the zlib.h and zconf.h include files that correspond to the version of zlib that's installed. You can rename the directories that you downloaded (they might be called "libpng-1.2.57" or "libpng12" and "zlib-1.2.3" or "zlib123") so that you have directories called "zlib" and "libpng". Your directory structure should look like this: .. (the parent directory) libpng (this directory) INSTALL (this file) README *.h *.c CMakeLists.txt => "cmake" script configuration files: configure.ac, configure, Makefile.am, Makefile.in, autogen.sh, config.guess, ltmain.sh, missing, aclocal.m4, config.h.in, config.sub, depcomp, install-sh, mkinstalldirs, test-pngtest.sh contrib gregbook pngminim pngminus pngsuite visupng projects cbuilder5 (Borland) visualc6 (msvc) visualc71 xcode scripts makefile.* *.def (module definition files) pngtest.png etc. zlib README *.h *.c contrib etc. If the line endings in the files look funny, you may wish to get the other distribution of libpng. It is available in both tar.gz (UNIX style line endings) and zip (DOS style line endings) formats. If you are building libpng with MSVC, you can enter the libpng projects\visualc6 or visualc71 directory and follow the instructions in README.txt. Otherwise enter the zlib directory and follow the instructions in zlib/README, then come back here and run "configure" or choose the appropriate makefile.sys in the scripts directory. Copy the file (or files) that you need from the scripts directory into this directory, for example MSDOS example: copy scripts\makefile.msc makefile UNIX example: cp scripts/makefile.std makefile Read the makefile to see if you need to change any source or target directories to match your preferences. Then read pngconf.h to see if you want to make any configuration changes. Then just run "make" which will create the libpng library in this directory and "make test" which will run a quick test that reads the "pngtest.png" file and writes a "pngout.png" file that should be identical to it. Look for "9782 zero samples" in the output of the test. For more confidence, you can run another test by typing "pngtest pngnow.png" and looking for "289 zero samples" in the output. Also, you can run "pngtest -m contrib/pngsuite/*.png" and compare your output with the result shown in contrib/pngsuite/README. Most of the makefiles will allow you to run "make install" to put the library in its final resting place (if you want to do that, run "make install" in the zlib directory first if necessary). Some also allow you to run "make test-installed" after you have run "make install". If you encounter a compiler error message complaining about the lines __png.h__ already includes setjmp.h; __dont__ include it again.; this means you have compiled another module that includes setjmp.h, which is hazardous because the two modules might not include exactly the same setjmp.h. If you are sure that you know what you are doing and that they are exactly the same, then you can comment out or delete the two lines. Better yet, use the cexcept interface instead, as demonstrated in contrib/visupng of the libpng distribution. Further information can be found in the README and libpng.txt files, in the individual makefiles, in png.h, and the manual pages libpng.3 and png.5. Using the ./configure script -- 16 December 2002. ================================================= The ./configure script should work compatibly with what scripts/makefile.* did, however there are some options you need to add to configure explicitly, which previously was done semi-automatically (if you didn't edit scripts/makefile.* yourself, that is) CFLAGS="-Wall -O -funroll-loops \ -malign-loops=2 -malign-functions=2" ./configure --prefix=/usr/include \ --with-pkgconfigdir=/usr/lib/pkgconfig --includedir=/usr/include You can alternatively specify --includedir=/usr/include, /usr/local/include, /usr/include/png12, or whatever.