\input texinfo @c -*- texinfo -*-
 
 @settitle Platform Specific information
 @titlepage
 @center @titlefont{Platform Specific information}
 @end titlepage
 
 @top
 
 @contents
 
 @chapter Unix-like
 

 Some parts of FFmpeg cannot be built with version 2.15 of the GNU

 assembler which is still provided by a few AMD64 distributions. To
 make sure your compiler really uses the required version of gas
 after a binutils upgrade, run:
 
 @example
 $(gcc -print-prog-name=as) --version
 @end example
 
 If not, then you should install a different compiler that has no
 hard-coded path to gas. In the worst case pass @code{--disable-asm}
 to configure.
 
 @section BSD
 

 BSD make will not build FFmpeg, you need to install and use GNU Make

 (@command{gmake}).

 
 @section (Open)Solaris
 

 GNU Make is required to build FFmpeg, so you have to invoke (@command{gmake}),

 standard Solaris Make will not work. When building with a non-c99 front-end
 (gcc, generic suncc) add either @code{--extra-libs=/usr/lib/values-xpg6.o}
 or @code{--extra-libs=/usr/lib/64/values-xpg6.o} to the configure options
 since the libc is not c99-compliant by default. The probes performed by
 configure may raise an exception leading to the death of configure itself
 due to a bug in the system shell. Simply invoke a different shell such as
 bash directly to work around this:
 
 @example
 bash ./configure
 @end example
 
 @anchor{Darwin}

 @section Darwin (Mac OS X, iPhone)

 
 The toolchain provided with Xcode is sufficient to build the basic
 unacelerated code.
 

 Mac OS X on PowerPC or ARM (iPhone) requires a preprocessor from

 @url{http://github.com/yuvi/gas-preprocessor} to build the optimized
 assembler functions. Just download the Perl script and put it somewhere

 in your PATH, FFmpeg's configure will pick it up automatically.

 Mac OS X on amd64 and x86 requires @command{yasm} to build most of the
 optimized assembler functions. @uref{http://www.finkproject.org/, Fink},
 @uref{http://www.gentoo.org/proj/en/gentoo-alt/prefix/bootstrap-macos.xml, Gentoo Prefix},
 @uref{http://mxcl.github.com/homebrew/, Homebrew}
 or @uref{http://www.macports.org, MacPorts} can easily provide it.

 
 
 @chapter DOS
 
 Using a cross-compiler is preferred for various reasons.
 @url{http://www.delorie.com/howto/djgpp/linux-x-djgpp.html}
 
 
 @chapter OS/2
 

 For information about compiling FFmpeg on OS/2 see

 @url{http://www.edm2.com/index.php/FFmpeg}.
 
 
 @chapter Windows
 

 To get help and instructions for building FFmpeg under Windows, check out
 the FFmpeg Windows Help Forum at
 @url{http://ffmpeg.arrozcru.org/}.
 

 @section Native Windows compilation
 

 FFmpeg can be built to run natively on Windows using the MinGW tools. Install

 the latest versions of MSYS and MinGW from @url{http://www.mingw.org/}.

 You can find detailed installation instructions in the download
 section and the FAQ.

 FFmpeg does not build out-of-the-box with the packages the automated MinGW

 installer provides. It also requires coreutils to be installed and many other

 packages updated to the latest version. The minimum versions for some packages

 are listed below:
 
 @itemize
 @item bash 3.1
 @item msys-make 3.81-2 (note: not mingw32-make)
 @item w32api 3.13
 @item mingw-runtime 3.15
 @end itemize
 

 FFmpeg automatically passes @code{-fno-common} to the compiler to work around

 a GCC bug (see @url{http://gcc.gnu.org/bugzilla/show_bug.cgi?id=37216}).
 
 Notes:
 
 @itemize
 
 @item Building natively using MSYS can be sped up by disabling implicit rules
 in the Makefile by calling @code{make -r} instead of plain @code{make}. This
 speed up is close to non-existent for normal one-off builds and is only

 noticeable when running make for a second time (for example during

 @code{make install}).
 

 @item In order to compile FFplay, you must have the MinGW development library

 of @uref{http://www.libsdl.org/, SDL} and @code{pkg-config} installed.

 @item By using @code{./configure --enable-shared} when configuring FFmpeg,
 you can build the FFmpeg libraries (e.g. libavutil, libavcodec,
 libavformat) as DLLs.

 
 @end itemize
 
 @section Microsoft Visual C++ compatibility
 

 As stated in the FAQ, FFmpeg will not compile under MSVC++. However, if you

 want to use the libav* libraries in your own applications, you can still
 compile those applications using MSVC++. But the libav* libraries you link
 to @emph{must} be built with MinGW. However, you will not be able to debug
 inside the libav* libraries, since MSVC++ does not recognize the debug
 symbols generated by GCC.
 We strongly recommend you to move over from MSVC++ to MinGW tools.
 

 This description of how to use the FFmpeg libraries with MSVC++ is based on

 Microsoft Visual C++ 2005 Express Edition. If you have a different version,
 you might have to modify the procedures slightly.
 
 @subsection Using static libraries
 

 Assuming you have just built and installed FFmpeg in @file{/usr/local}:

 
 @enumerate
 
 @item Create a new console application ("File / New / Project") and then
 select "Win32 Console Application". On the appropriate page of the
 Application Wizard, uncheck the "Precompiled headers" option.
 
 @item Write the source code for your application, or, for testing, just
 copy the code from an existing sample application into the source file
 that MSVC++ has already created for you. For example, you can copy

 @file{libavformat/output-example.c} from the FFmpeg distribution.

 
 @item Open the "Project / Properties" dialog box. In the "Configuration"
 combo box, select "All Configurations" so that the changes you make will
 affect both debug and release builds. In the tree view on the left hand
 side, select "C/C++ / General", then edit the "Additional Include

 Directories" setting to contain the path where the FFmpeg includes were

 installed (i.e. @file{c:\msys\1.0\local\include}).
 Do not add MinGW's include directory here, or the include files will
 conflict with MSVC's.
 
 @item Still in the "Project / Properties" dialog box, select
 "Linker / General" from the tree view and edit the
 "Additional Library Directories" setting to contain the @file{lib}

 directory where FFmpeg was installed (i.e. @file{c:\msys\1.0\local\lib}),

 the directory where MinGW libs are installed (i.e. @file{c:\mingw\lib}),
 and the directory where MinGW's GCC libs are installed
 (i.e. @file{C:\mingw\lib\gcc\mingw32\4.2.1-sjlj}). Then select
 "Linker / Input" from the tree view, and add the files @file{libavformat.a},
 @file{libavcodec.a}, @file{libavutil.a}, @file{libmingwex.a},
 @file{libgcc.a}, and any other libraries you used (i.e. @file{libz.a})
 to the end of "Additional Dependencies".
 
 @item Now, select "C/C++ / Code Generation" from the tree view. Select
 "Debug" in the "Configuration" combo box. Make sure that "Runtime
 Library" is set to "Multi-threaded Debug DLL". Then, select "Release" in
 the "Configuration" combo box and make sure that "Runtime Library" is
 set to "Multi-threaded DLL".
 
 @item Click "OK" to close the "Project / Properties" dialog box.
 

 @item MSVC++ lacks some C99 header files that are fundamental for FFmpeg.

 Get msinttypes from @url{http://code.google.com/p/msinttypes/downloads/list}
 and install it in MSVC++'s include directory
 (i.e. @file{C:\Program Files\Microsoft Visual Studio 8\VC\include}).
 
 @item MSVC++ also does not understand the @code{inline} keyword used by

 FFmpeg, so you must add this line before @code{#include}ing libav*:

 @example
 #define inline _inline
 @end example
 
 @item Build your application, everything should work.
 
 @end enumerate
 
 @subsection Using shared libraries
 
 This is how to create DLL and LIB files that are compatible with MSVC++:
 

 @enumerate
 
 @item Add a call to @file{vcvars32.bat} (which sets up the environment
 variables for the Visual C++ tools) as the first line of @file{msys.bat}.
 The standard location for @file{vcvars32.bat} is
 @file{C:\Program Files\Microsoft Visual Studio 8\VC\bin\vcvars32.bat},
 and the standard location for @file{msys.bat} is @file{C:\msys\1.0\msys.bat}.
 If this corresponds to your setup, add the following line as the first line
 of @file{msys.bat}:
 
 @example
 call "C:\Program Files\Microsoft Visual Studio 8\VC\bin\vcvars32.bat"
 @end example
 
 Alternatively, you may start the @file{Visual Studio 2005 Command Prompt},
 and run @file{c:\msys\1.0\msys.bat} from there.
 
 @item Within the MSYS shell, run @code{lib.exe}. If you get a help message
 from @file{Microsoft (R) Library Manager}, this means your environment
 variables are set up correctly, the @file{Microsoft (R) Library Manager}
 is on the path and will be used by FFmpeg to create
 MSVC++-compatible import libraries.
 
 @item Build FFmpeg with

 
 @example
 ./configure --enable-shared
 make
 make install
 @end example
 
 Your install path (@file{/usr/local/} by default) should now have the
 necessary DLL and LIB files under the @file{bin} directory.
 

 @end enumerate
 

 Alternatively, build the libraries with a cross compiler, according to
 the instructions below in @ref{Cross compilation for Windows with Linux}.
 
 To use those files with MSVC++, do the same as you would do with
 the static libraries, as described above. But in Step 4,
 you should only need to add the directory where the LIB files are installed
 (i.e. @file{c:\msys\usr\local\bin}). This is not a typo, the LIB files are
 installed in the @file{bin} directory. And instead of adding the static
 libraries (@file{libxxx.a} files) you should add the MSVC import libraries
 (@file{avcodec.lib}, @file{avformat.lib}, and
 @file{avutil.lib}). Note that you should not use the GCC import
 libraries (@file{libxxx.dll.a} files), as these will give you undefined
 reference errors. There should be no need for @file{libmingwex.a},
 @file{libgcc.a}, and @file{wsock32.lib}, nor any other external library
 statically linked into the DLLs.
 

 FFmpeg headers do not declare global data for Windows DLLs through the usual

 dllexport/dllimport interface. Such data will be exported properly while
 building, but to use them in your MSVC++ code you will have to edit the
 appropriate headers and mark the data as dllimport. For example, in
 libavutil/pixdesc.h you should have:
 @example
 extern __declspec(dllimport) const AVPixFmtDescriptor av_pix_fmt_descriptors[];
 @end example
 
 Note that using import libraries created by dlltool requires
 the linker optimization option to be set to
 "References: Keep Unreferenced Data (@code{/OPT:NOREF})", otherwise
 the resulting binaries will fail during runtime. This isn't
 required when using import libraries generated by lib.exe.
 This issue is reported upstream at
 @url{http://sourceware.org/bugzilla/show_bug.cgi?id=12633}.
 
 To create import libraries that work with the @code{/OPT:REF} option
 (which is enabled by default in Release mode), follow these steps:
 
 @enumerate
 

 @item Open @emph{Visual Studio 2005 Command Prompt}.

 
 Alternatively, in a normal command line prompt, call @file{vcvars32.bat}
 which sets up the environment variables for the Visual C++ tools
 (the standard location for this file is
 @file{C:\Program Files\Microsoft Visual Studio 8\VC\bin\vcvars32.bat}).
 
 @item Enter the @file{bin} directory where the created LIB and DLL files
 are stored.
 

 @item Generate new import libraries with @command{lib.exe}:

 
 @example

 lib /machine:i386 /def:..\lib\foo-version.def  /out:foo.lib

 @end example
 

 Replace @code{foo-version} and @code{foo} with the respective library names.
 

 @end enumerate
 
 @anchor{Cross compilation for Windows with Linux}
 @section Cross compilation for Windows with Linux
 
 You must use the MinGW cross compilation tools available at
 @url{http://www.mingw.org/}.
 

 Then configure FFmpeg with the following options:

 @example
 ./configure --target-os=mingw32 --cross-prefix=i386-mingw32msvc-
 @end example
 (you can change the cross-prefix according to the prefix chosen for the
 MinGW tools).
 

 Then you can easily test FFmpeg with @uref{http://www.winehq.com/, Wine}.

 
 @section Compilation under Cygwin
 
 Please use Cygwin 1.7.x as the obsolete 1.5.x Cygwin versions lack
 llrint() in its C library.
 
 Install your Cygwin with all the "Base" packages, plus the
 following "Devel" ones:
 @example
 binutils, gcc4-core, make, git, mingw-runtime, texi2html
 @end example
 
 And the following "Utils" one:
 @example
 diffutils
 @end example
 
 Then run
 
 @example
 ./configure
 @end example
 
 to make a static build.
 

 To build shared libraries add a special compiler flag to work around current
 @code{gcc4-core} package bugs in addition to the normal configure flags:

 
 @example
 ./configure --enable-shared --disable-static --extra-cflags=-fno-reorder-functions
 @end example
 

 If you want to build FFmpeg with additional libraries, download Cygwin

 "Devel" packages for Ogg and Vorbis from any Cygwin packages repository:
 @example
 libogg-devel, libvorbis-devel
 @end example
 
 These library packages are only available from
 @uref{http://sourceware.org/cygwinports/, Cygwin Ports}:
 
 @example

 yasm, libSDL-devel, libfaac-devel, libaacplus-devel, libgsm-devel, libmp3lame-devel,

 libschroedinger1.0-devel, speex-devel, libtheora-devel, libxvidcore-devel

 @end example
 

 The recommendation for x264 is to build it from source, as it evolves too
 quickly for Cygwin Ports to be up to date.

 
 @section Crosscompilation for Windows under Cygwin
 
 With Cygwin you can create Windows binaries that do not need the cygwin1.dll.
 
 Just install your Cygwin as explained before, plus these additional
 "Devel" packages:
 @example
 gcc-mingw-core, mingw-runtime, mingw-zlib
 @end example
 
 and add some special flags to your configure invocation.
 
 For a static build run
 @example
 ./configure --target-os=mingw32 --extra-cflags=-mno-cygwin --extra-libs=-mno-cygwin
 @end example
 
 and for a build with shared libraries
 @example
 ./configure --target-os=mingw32 --enable-shared --disable-static --extra-cflags=-mno-cygwin --extra-libs=-mno-cygwin
 @end example
 
 @bye