for more formats. None of them are used by default, their use has to be
explicitly requested by passing the appropriate flags to @file{./configure}.
-@section AMR
+@section OpenCORE AMR
-AMR comes in two different flavors, wideband and narrowband. FFmpeg can make
-use of the AMR wideband (floating-point mode) and the AMR narrowband
-(floating-point mode) reference decoders and encoders (libamr) as well as
-the OpenCORE libraries for AMR-NB decoding/encoding and AMR-WB decoding.
+FFmpeg can make use of the OpenCORE libraries for AMR-NB
+decoding/encoding and AMR-WB decoding.
-@subsection OpenCORE
-
-Go to @url{http://gitorious.org/opencore-amr/} and follow the instructions for
+Go to @url{http://sourceforge.net/projects/opencore-amr/} and follow the instructions for
installing the libraries. Then pass @code{--enable-libopencore-amrnb} and/or
@code{--enable-libopencore-amrwb} to configure to enable the libraries.
upgrade FFmpeg's license to LGPL version 3 (or if you have enabled
GPL components, GPL version 3) to use it.
-@subsection libamr
-
-Go to @url{http://www.penguin.cz/~utx/amr} and follow the instructions for
-installing the libraries. Then pass @code{--enable-libamr-nb} and/or
-@code{--enable-libamr-wb} to configure to enable the libraries.
-
-Note that libamr is copyrighted without any sort of license grant. This means
-that you can use it if you legally obtained it but you are not allowed to
-redistribute it in any way. @strong{Any FFmpeg binaries with libamr support
-you create are non-free and unredistributable!}
-
@chapter Supported File Formats and Codecs
-You can use the @code{-formats} option to have an exhaustive list.
+You can use the @code{-formats} and @code{-codecs} options to have an exhaustive list.
@section File Formats
@item 4xm @tab @tab X
@tab 4X Technologies format, used in some games.
@item 8088flex TMV @tab @tab X
+@item Adobe Filmstrip @tab X @tab X
@item Audio IFF (AIFF) @tab X @tab X
@item American Laser Games MM @tab @tab X
@tab Multimedia format used in games like Mad Dog McCree.
@item 3GPP AMR @tab X @tab X
+@item Apple HTTP Live Streaming @tab @tab X
@item ASF @tab X @tab X
@item AVI @tab X @tab X
@item AVISynth @tab @tab X
@tab Audio and video format used in some games by Beam Software.
@item Bethesda Softworks VID @tab @tab X
@tab Used in some games from Bethesda Softworks.
+@item Bink @tab @tab X
+ @tab Multimedia format used by many games.
@item Brute Force & Ignorance @tab @tab X
@tab Used in the game Flash Traffic: City of Angels.
@item Interplay C93 @tab @tab X
@tab Used in the game Cyberia from Interplay.
@item Delphine Software International CIN @tab @tab X
@tab Multimedia format used by Delphine Software games.
+@item CD+G @tab @tab X
+ @tab Video format used by CD+G karaoke disks
+@item Core Audio Format @tab @tab X
+ @tab Apple Core Audio Format
@item CRC testing format @tab X @tab
@item Creative Voice @tab X @tab X
@tab Created for the Sound Blaster Pro.
@item CRYO APC @tab @tab X
@tab Audio format used in some games by CRYO Interactive Entertainment.
@item D-Cinema audio @tab X @tab X
+@item Deluxe Paint Animation @tab @tab X
@item DV video @tab X @tab X
@item DXA @tab @tab X
@tab This format is used in the non-Windows version of the Feeble Files
@item id Quake II CIN video @tab @tab X
@item id RoQ @tab X @tab X
@tab Used in Quake III, Jedi Knight 2, other computer games.
+@item IEC61937 encapsulation @tab X @tab X
@item IFF @tab @tab X
@tab Interchange File Format
@item Interplay MVE @tab @tab X
@tab Format used in various Interplay computer games.
+@item IV8 @tab @tab X
+ @tab A format generated by IndigoVision 8000 video server.
+@item IVF (On2) @tab @tab X
+ @tab A format used by libvpx
@item LMLM4 @tab @tab X
@tab Used by Linux Media Labs MPEG-4 PCI boards
+@item LXF @tab @tab X
+ @tab VR native stream format, used by Leitch/Harris' video servers.
@item Matroska @tab X @tab X
@item Matroska audio @tab X @tab
+@item FFmpeg metadata @tab X @tab X
+ @tab Metadata in text format.
@item MAXIS XA @tab @tab X
@tab Used in Sim City 3000; file extension .xa.
+@item MD Studio @tab @tab X
+@item Mobotix .mxg @tab @tab X
@item Monkey's Audio @tab @tab X
@item Motion Pixels MVI @tab @tab X
@item MOV/QuickTime/MP4 @tab X @tab X
@item QCP @tab @tab X
@item raw ADTS (AAC) @tab X @tab X
@item raw AC-3 @tab X @tab X
-@item raw Chinese AVS video @tab @tab X
+@item raw Chinese AVS video @tab X @tab X
@item raw CRI ADX @tab X @tab X
@item raw Dirac @tab X @tab X
@item raw DNxHD @tab X @tab X
@item RL2 @tab @tab X
@tab Audio and video format used in some games by Entertainment Software Partners.
@item RPL/ARMovie @tab @tab X
-@item RTP @tab @tab X
-@item RTSP @tab @tab X
+@item Lego Mindstorms RSO @tab X @tab X
+@item RTMP @tab X @tab X
+ @tab Output is performed by publishing stream to RTMP server
+@item RTP @tab X @tab X
+@item RTSP @tab X @tab X
+@item SAP @tab X @tab X
@item SDP @tab @tab X
@item Sega FILM/CPK @tab @tab X
@tab Used in many Sega Saturn console games.
@item Sony OpenMG (OMA) @tab @tab X
@tab Audio format used in Sony Sonic Stage and Sony Vegas.
@item Sony PlayStation STR @tab @tab X
+@item Sony Wave64 (W64) @tab @tab X
@item SoX native format @tab X @tab X
@item SUN AU format @tab X @tab X
+@item Text files @tab @tab X
@item THP @tab @tab X
@tab Used on the Nintendo GameCube.
@item Tiertex Limited SEQ @tab @tab X
@item VC-1 test bitstream @tab X @tab X
@item WAV @tab X @tab X
@item WavPack @tab @tab X
+@item WebM @tab X @tab X
+@item Windows Televison (WTV) @tab @tab X
@item Wing Commander III movie @tab @tab X
@tab Multimedia format used in Origin's Wing Commander III computer game.
@item Westwood Studios audio @tab @tab X
@item Westwood Studios VQA @tab @tab X
@tab Multimedia format used in Westwood Studios games.
@item YUV4MPEG pipe @tab X @tab X
+@item Psygnosis YOP @tab @tab X
@end multitable
@code{X} means that encoding (resp. decoding) is supported.
@tab Portable GrayMap image
@item PGMYUV @tab X @tab X
@tab PGM with U and V components in YUV 4:2:0
+@item PIC @tab @tab X
+ @tab Pictor/PC Paint
@item PNG @tab X @tab X
@tab 2/4 bpp not supported yet
@item PPM @tab X @tab X
@item 8088flex TMV @tab @tab X
@item 8SVX exponential @tab @tab X
@item 8SVX fibonacci @tab @tab X
+@item A64 multicolor @tab X @tab
+ @tab Creates video suitable to be played on a commodore 64 (multicolor mode).
@item American Laser Games MM @tab @tab X
@tab Used in games like Mad Dog McCree.
@item AMV Video @tab @tab X
@tab Used in Chinese MP3 players.
+@item ANSI/ASCII art @tab @tab X
@item Apple MJPEG-B @tab @tab X
@item Apple QuickDraw @tab @tab X
@tab fourcc: qdrw
@tab fourcc: VCR1
@item ATI VCR2 @tab @tab X
@tab fourcc: VCR2
+@item Auravision Aura @tab @tab X
+@item Auravision Aura 2 @tab @tab X
@item Autodesk Animator Flic video @tab @tab X
@item Autodesk RLE @tab @tab X
@tab fourcc: AASC
@item Beam Software VB @tab @tab X
@item Bethesda VID video @tab @tab X
@tab Used in some games from Bethesda Softworks.
+@item Bink Video @tab @tab X
+ @tab Support for version 'b' is missing.
@item Brute Force & Ignorance @tab @tab X
@tab Used in the game Flash Traffic: City of Angels.
@item C93 video @tab @tab X
@tab Codec used in Cyberia game.
@item CamStudio @tab @tab X
@tab fourcc: CSCD
-@item Chinese AVS video @tab @tab X
- @tab AVS1-P2, JiZhun profile
+@item CD+G @tab @tab X
+ @tab Video codec for CD+G karaoke disks
+@item Chinese AVS video @tab E @tab X
+ @tab AVS1-P2, JiZhun profile, encoding through external library libxavs
@item Delphine Software International CIN video @tab @tab X
@tab Codec used in Delphine Software International games.
@item Cinepak @tab @tab X
@item Creative YUV (CYUV) @tab @tab X
@item Dirac @tab E @tab E
@tab supported through external libdirac/libschroedinger libraries
+@item Deluxe Paint Animation @tab @tab X
@item DNxHD @tab X @tab X
@tab aka SMPTE VC3
@item Duck TrueMotion 1.0 @tab @tab X
@tab Codec originally used in Feeble Files game.
@item Electronic Arts CMV video @tab @tab X
@tab Used in NHL 95 game.
+@item Electronic Arts Madcow video @tab @tab X
@item Electronic Arts TGV video @tab @tab X
@item Electronic Arts TGQ video @tab @tab X
@item Electronic Arts TQI video @tab @tab X
@item Escape 124 @tab @tab X
-@item FFmpeg codec #1 @tab X @tab X
+@item FFmpeg video codec #1 @tab X @tab X
@tab experimental lossless codec (fourcc: FFV1)
@item Flash Screen Video v1 @tab X @tab X
@tab fourcc: FSV1
@tab Used in Quake II.
@item id RoQ video @tab X @tab X
@tab Used in Quake III, Jedi Knight 2, other computer games.
+@item IFF ILBM @tab @tab X
+ @tab IFF interlaved bitmap
+@item IFF ByteRun1 @tab @tab X
+ @tab IFF run length encoded bitmap
@item Intel H.263 @tab @tab X
@item Intel Indeo 2 @tab @tab X
@item Intel Indeo 3 @tab @tab X
+@item Intel Indeo 5 @tab @tab X
@item Interplay C93 @tab @tab X
@tab Used in the game Cyberia from Interplay.
@item Interplay MVE video @tab @tab X
@tab Used in Interplay .MVE files.
@item Karl Morton's video codec @tab @tab X
@tab Codec used in Worms games.
+@item Kega Game Video (KGV1) @tab @tab X
+ @tab Kega emulator screen capture codec.
+@item Lagarith @tab @tab X
@item LCL (LossLess Codec Library) MSZH @tab @tab X
@item LCL (LossLess Codec Library) ZLIB @tab E @tab E
@item LOCO @tab @tab X
@item MPEG-2 video @tab X @tab X
@item MPEG-4 part 2 @tab X @tab X
@ libxvidcore can be used alternatively for encoding.
-@item MPEG-4 part 2 Microsoft variant version 1 @tab X @tab X
+@item MPEG-4 part 2 Microsoft variant version 1 @tab @tab X
@item MPEG-4 part 2 Microsoft variant version 2 @tab X @tab X
@item MPEG-4 part 2 Microsoft variant version 3 @tab X @tab X
@item Nintendo Gamecube THP video @tab @tab X
@tab fourcc: VP50
@item On2 VP6 @tab @tab X
@tab fourcc: VP60,VP61,VP62
+@item VP8 @tab E @tab X
+ @tab fourcc: VP80, encoding supported through external library libvpx
@item planar RGB @tab @tab X
@tab fourcc: 8BPS
@item Q-team QPEG @tab @tab X
@tab fourcc: 'smc '
@item QuickTime video (RPZA) @tab @tab X
@tab fourcc: rpza
+@item R10K AJA Kona 10-bit RGB Codec @tab @tab X
+@item R210 Quicktime Uncompressed RGB 10-bit @tab @tab X
@item Raw Video @tab X @tab X
@item RealVideo 1.0 @tab X @tab X
@item RealVideo 2.0 @tab X @tab X
@item Winnov WNV1 @tab @tab X
@item WMV7 @tab X @tab X
@item YAMAHA SMAF @tab X @tab X
+@item Psygnosis YOP Video @tab @tab X
@item ZLIB @tab X @tab X
@tab part of LCL, encoder experimental
@item Zip Motion Blocks Video @tab X @tab X
@item ADPCM Electronic Arts R2 @tab @tab X
@item ADPCM Electronic Arts R3 @tab @tab X
@item ADPCM Electronic Arts XAS @tab @tab X
+@item ADPCM G.722 @tab X @tab X
@item ADPCM G.726 @tab X @tab X
@item ADPCM IMA AMV @tab @tab X
@tab Used in AMV files
@item ADPCM Westwood Studios IMA @tab @tab X
@tab Used in Westwood Studios games like Command and Conquer.
@item ADPCM Yamaha @tab X @tab X
-@item AMR-NB @tab E @tab E
- @tab supported through external libraries libamrnb and libopencore-amrnb
-@item AMR-WB @tab E @tab E
- @tab decoding supported through external libraries libamrwb and libopencore-amrwb,
- encoding supported through external library libamrwb
+@item AMR-NB @tab E @tab X
+ @tab encoding supported through external library libopencore-amrnb
+@item AMR-WB @tab @tab X
@item Apple lossless audio @tab X @tab X
@tab QuickTime fourcc 'alac'
+@item Atrac 1 @tab @tab X
@item Atrac 3 @tab @tab X
+@item Bink Audio @tab @tab X
+ @tab Used in Bink and Smacker files in many games.
@item Delphine Software International CIN audio @tab @tab X
@tab Codec used in Delphine Software International games.
@item COOK @tab @tab X
@item DV audio @tab @tab X
@item Enhanced AC-3 @tab @tab X
@item FLAC (Free Lossless Audio Codec) @tab X @tab IX
-@item G.729 @tab @tab X
-@item GSM @tab E @tab E
- @tab supported through external library libgsm
-@item GSM Microsoft variant @tab E @tab E
- @tab supported through external library libgsm
+@item GSM @tab E @tab X
+ @tab encoding supported through external library libgsm
+@item GSM Microsoft variant @tab E @tab X
+ @tab encoding supported through external library libgsm
@item IMC (Intel Music Coder) @tab @tab X
@item MACE (Macintosh Audio Compression/Expansion) 3:1 @tab @tab X
@item MACE (Macintosh Audio Compression/Expansion) 6:1 @tab @tab X
@item MP2 (MPEG audio layer 2) @tab IX @tab IX
@item MP3 (MPEG audio layer 3) @tab E @tab IX
@tab encoding supported through external library LAME, ADU MP3 and MP3onMP4 also supported
+@item MPEG-4 Audio Lossless Coding (ALS) @tab @tab X
@item Musepack SV7 @tab @tab X
@item Musepack SV8 @tab @tab X
@item Nellymoser Asao @tab X @tab X
@item PCM signed 24-bit little-endian @tab X @tab X
@item PCM signed 32-bit big-endian @tab X @tab X
@item PCM signed 32-bit little-endian @tab X @tab X
+@item PCM signed 16/20/24-bit big-endian in MPEG-TS @tab @tab X
@item PCM unsigned 8-bit @tab X @tab X
@item PCM unsigned 16-bit big-endian @tab X @tab X
@item PCM unsigned 16-bit little-endian @tab X @tab X
@item QCELP / PureVoice @tab @tab X
@item QDesign Music Codec 2 @tab @tab X
@tab There are still some distortions.
-@item RealAudio 1.0 (14.4K) @tab @tab X
+@item RealAudio 1.0 (14.4K) @tab X @tab X
@tab Real 14400 bit/s codec
@item RealAudio 2.0 (28.8K) @tab @tab X
@tab Real 28800 bit/s codec
@item RealAudio 3.0 (dnet) @tab IX @tab X
@tab Real low bitrate AC-3 codec
+@item RealAudio SIPR / ACELP.NET @tab @tab X
@item Shorten @tab @tab X
@item Sierra VMD audio @tab @tab X
@tab Used in Sierra VMD files.
@item True Audio (TTA) @tab @tab X
@item TrueHD @tab @tab X
@tab Used in HD-DVD and Blu-Ray discs.
+@item TwinVQ (VQF flavor) @tab @tab X
@item Vorbis @tab E @tab X
- @ A native but very primitive encoder exists.
+ @tab A native but very primitive encoder exists.
@item WavPack @tab @tab X
@item Westwood Audio (SND1) @tab @tab X
@item Windows Media Audio 1 @tab X @tab X
@item Windows Media Audio 2 @tab X @tab X
+@item Windows Media Audio Pro @tab @tab X
+@item Windows Media Audio Voice @tab @tab X
@end multitable
@code{X} means that encoding (resp. decoding) is supported.
@multitable @columnfractions .4 .1 .1 .1 .1
@item Name @tab Muxing @tab Demuxing @tab Encoding @tab Decoding
-@item SSA/ASS @tab X @tab X
+@item SSA/ASS @tab X @tab X @tab X @tab X
@item DVB @tab X @tab X @tab X @tab X
@item DVD @tab X @tab X @tab X @tab X
-@item XSUB @tab @tab @tab @tab X
+@item PGS @tab @tab @tab @tab X
+@item SubRip (SRT) @tab X @tab X @tab @tab X
+@item XSUB @tab @tab @tab X @tab X
@end multitable
@code{X} means that the feature is supported.
@item file @tab X
@item Gopher @tab X
@item HTTP @tab X
+@item MMS @tab X
@item pipe @tab X
@item RTP @tab X
@item TCP @tab X
@multitable @columnfractions .4 .1 .1
@item Name @tab Input @tab Output
@item ALSA @tab X @tab X
-@item BEOS audio @tab X @tab X
@item BKTR @tab X @tab
@item DV1394 @tab X @tab
@item JACK @tab X @tab
@chapter Platform Specific information
-@section BSD
+@section DOS
+
+Using a cross-compiler is preferred for various reasons.
+
+@subsection DJGPP
+
+FFmpeg cannot be compiled because of broken system headers, add
+@code{--extra-cflags=-U__STRICT_ANSI__} to the configure options as a
+workaround.
+
+@section OS/2
+
+For information about compiling FFmpeg on OS/2 see
+@url{http://www.edm2.com/index.php/FFmpeg}.
+
+@section 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.
+
+@subsection BSD
BSD make will not build FFmpeg, you need to install and use GNU Make
(@file{gmake}).
+@subsubsection FreeBSD
+
+FreeBSD will not compile out-of-the-box due to broken system headers.
+Passing @code{--extra-cflags=-D__BSD_VISIBLE} to configure will work
+around the problem. This may have unexpected sideeffects, so use it at
+your own risk. If you care about FreeBSD, please make an attempt at
+getting the system headers fixed.
+
+@subsection (Open)Solaris
+
+GNU Make is required to build FFmpeg, so you have to invoke (@file{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
+
+@subsection Darwin (MacOS X, iPhone)
+
+MacOS 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.
+
@section Windows
To get help and instructions for building FFmpeg under Windows, check out
Within the MSYS shell, configure and make with:
@example
-./configure --enable-memalign-hack --extra-cflags=-fno-common
+./configure --enable-memalign-hack
make
make install
@end example
@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 in
+@code{make install}).
+
@item In order to compile FFplay, you must have the MinGW development library
of SDL. Get it from @url{http://www.libsdl.org}.
Edit the @file{bin/sdl-config} script so that it points to the correct prefix
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 @file{libxx.a}
-files, you should add @file{avcodec.lib}, @file{avformat.lib}, and
-@file{avutil.lib}. There should be no need for @file{libmingwex.a},
+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}, @file{avcore.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. The @file{bin} directory contains a bunch
of DLL files, but the ones that are actually used to run your application
are the ones with a major version number in their filenames
(i.e. @file{avcodec-51.dll}).
+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
+
@subsection Cross compilation for Windows with Linux
You must use the MinGW cross compilation tools available at
@subsection Compilation under Cygwin
-The main issue with the 1.5.x Cygwin versions is that newlib, its C library,
-does not contain llrint(). You need to upgrade to the unstable 1.7.x versions,
-or leverage the implementation in MinGW (as explained below).
+Please use Cygwin 1.7.x as the obsolete 1.5.x Cygwin versions lack
+llrint() in its C library.
-Just install your Cygwin with all the "Base" packages, plus the
+Install your Cygwin with all the "Base" packages, plus the
following "Devel" ones:
@example
-binutils, gcc-core, make, subversion, mingw-runtime, diffutils
+binutils, gcc4-core, make, subversion, mingw-runtime, texi2html
@end example
-The experimental gcc4 package is still buggy, hence please
-use the official gcc 3.4.4 or a 4.2.x compiled from source by yourself.
-
-Install the current binutils-20080624-2 as they work fine (the old
-binutils-20060709-1 proved buggy on shared builds).
-
-Then create a small library that just contains llrint():
-
+And the following "Utils" one:
@example
-ar x /usr/lib/mingw/libmingwex.a llrint.o
-ar cq /usr/local/lib/libllrint.a llrint.o
+diffutils
@end example
Then run
@example
-./configure --enable-static --disable-shared --extra-ldflags='-L /usr/local/lib' --extra-libs='-l llrint'
+./configure --enable-static --disable-shared
@end example
-to make a static build or
+to make a static build.
+
+The current @code{gcc4-core} package is buggy and needs this flag to build
+shared libraries:
@example
-./configure --enable-shared --disable-static --extra-ldflags='-L /usr/local/lib' --extra-libs='-l llrint'
+./configure --enable-shared --disable-static --extra-cflags=-fno-reorder-functions
@end example
-to build shared libraries.
-
If you want to build FFmpeg with additional libraries, download Cygwin
"Devel" packages for Ogg and Vorbis from any Cygwin packages repository:
@example
(@url{http://sourceware.org/cygwinports/}) :
@example
-yasm, libSDL-devel, libdirac-devel, libfaac-devel, libfaad-devel, libgsm-devel,
+yasm, libSDL-devel, libdirac-devel, libfaac-devel, libgsm-devel,
libmp3lame-devel, libschroedinger1.0-devel, speex-devel, libtheora-devel,
libxvidcore-devel
@end example
./configure --target-os=mingw32 --enable-memalign-hack --enable-shared --disable-static --extra-cflags=-mno-cygwin --extra-libs=-mno-cygwin
@end example
-@section BeOS
-
-BeOS support is broken in mysterious ways.
-
-@section OS/2
-
-For information about compiling FFmpeg on OS/2 see
-@url{http://www.edm2.com/index.php/FFmpeg}.
-
-@chapter Developers Guide
-
-@section API
-@itemize @bullet
-@item libavcodec is the library containing the codecs (both encoding and
-decoding). Look at @file{libavcodec/apiexample.c} to see how to use it.
-
-@item libavformat is the library containing the file format handling (mux and
-demux code for several formats). Look at @file{ffplay.c} to use it in a
-player. See @file{libavformat/output-example.c} to use it to generate
-audio or video streams.
-
-@end itemize
-
-@section Integrating libavcodec or libavformat in your program
-
-You can integrate all the source code of the libraries to link them
-statically to avoid any version problem. All you need is to provide a
-'config.mak' and a 'config.h' in the parent directory. See the defines
-generated by ./configure to understand what is needed.
-
-You can use libavcodec or libavformat in your commercial program, but
-@emph{any patch you make must be published}. The best way to proceed is
-to send your patches to the FFmpeg mailing list.
-
-@node Coding Rules
-@section Coding Rules
-
-FFmpeg is programmed in the ISO C90 language with a few additional
-features from ISO C99, namely:
-@itemize @bullet
-@item
-the @samp{inline} keyword;
-@item
-@samp{//} comments;
-@item
-designated struct initializers (@samp{struct s x = @{ .i = 17 @};})
-@item
-compound literals (@samp{x = (struct s) @{ 17, 23 @};})
-@end itemize
-
-These features are supported by all compilers we care about, so we will not
-accept patches to remove their use unless they absolutely do not impair
-clarity and performance.
-
-All code must compile with GCC 2.95 and GCC 3.3. Currently, FFmpeg also
-compiles with several other compilers, such as the Compaq ccc compiler
-or Sun Studio 9, and we would like to keep it that way unless it would
-be exceedingly involved. To ensure compatibility, please do not use any
-additional C99 features or GCC extensions. Especially watch out for:
-@itemize @bullet
-@item
-mixing statements and declarations;
-@item
-@samp{long long} (use @samp{int64_t} instead);
-@item
-@samp{__attribute__} not protected by @samp{#ifdef __GNUC__} or similar;
-@item
-GCC statement expressions (@samp{(x = (@{ int y = 4; y; @})}).
-@end itemize
-
-Indent size is 4.
-The presentation is the one specified by 'indent -i4 -kr -nut'.
-The TAB character is forbidden outside of Makefiles as is any
-form of trailing whitespace. Commits containing either will be
-rejected by the Subversion repository.
-
-The main priority in FFmpeg is simplicity and small code size in order to
-minimize the bug count.
-
-Comments: Use the JavaDoc/Doxygen
-format (see examples below) so that code documentation
-can be generated automatically. All nontrivial functions should have a comment
-above them explaining what the function does, even if it is just one sentence.
-All structures and their member variables should be documented, too.
-@example
-/**
- * @@file mpeg.c
- * MPEG codec.
- * @@author ...
- */
-
-/**
- * Summary sentence.
- * more text ...
- * ...
- */
-typedef struct Foobar@{
- int var1; /**< var1 description */
- int var2; ///< var2 description
- /** var3 description */
- int var3;
-@} Foobar;
-
-/**
- * Summary sentence.
- * more text ...
- * ...
- * @@param my_parameter description of my_parameter
- * @@return return value description
- */
-int myfunc(int my_parameter)
-...
-@end example
-
-fprintf and printf are forbidden in libavformat and libavcodec,
-please use av_log() instead.
-
-Casts should be used only when necessary. Unneeded parentheses
-should also be avoided if they don't make the code easier to understand.
-
-@section Development Policy
-
-@enumerate
-@item
- Contributions should be licensed under the LGPL 2.1, including an
- "or any later version" clause, or the MIT license. GPL 2 including
- an "or any later version" clause is also acceptable, but LGPL is
- preferred.
-@item
- You must not commit code which breaks FFmpeg! (Meaning unfinished but
- enabled code which breaks compilation or compiles but does not work or
- breaks the regression tests)
- You can commit unfinished stuff (for testing etc), but it must be disabled
- (#ifdef etc) by default so it does not interfere with other developers'
- work.
-@item
- You do not have to over-test things. If it works for you, and you think it
- should work for others, then commit. If your code has problems
- (portability, triggers compiler bugs, unusual environment etc) they will be
- reported and eventually fixed.
-@item
- Do not commit unrelated changes together, split them into self-contained
- pieces. Also do not forget that if part B depends on part A, but A does not
- depend on B, then A can and should be committed first and separate from B.
- Keeping changes well split into self-contained parts makes reviewing and
- understanding them on the commit log mailing list easier. This also helps
- in case of debugging later on.
- Also if you have doubts about splitting or not splitting, do not hesitate to
- ask/discuss it on the developer mailing list.
-@item
- Do not change behavior of the program (renaming options etc) without
- first discussing it on the ffmpeg-devel mailing list. Do not remove
- functionality from the code. Just improve!
-
- Note: Redundant code can be removed.
-@item
- Do not commit changes to the build system (Makefiles, configure script)
- which change behavior, defaults etc, without asking first. The same
- applies to compiler warning fixes, trivial looking fixes and to code
- maintained by other developers. We usually have a reason for doing things
- the way we do. Send your changes as patches to the ffmpeg-devel mailing
- list, and if the code maintainers say OK, you may commit. This does not
- apply to files you wrote and/or maintain.
-@item
- We refuse source indentation and other cosmetic changes if they are mixed
- with functional changes, such commits will be rejected and removed. Every
- developer has his own indentation style, you should not change it. Of course
- if you (re)write something, you can use your own style, even though we would
- prefer if the indentation throughout FFmpeg was consistent (Many projects
- force a given indentation style - we do not.). If you really need to make
- indentation changes (try to avoid this), separate them strictly from real
- changes.
-
- NOTE: If you had to put if()@{ .. @} over a large (> 5 lines) chunk of code,
- then either do NOT change the indentation of the inner part within (do not
- move it to the right)! or do so in a separate commit
-@item
- Always fill out the commit log message. Describe in a few lines what you
- changed and why. You can refer to mailing list postings if you fix a
- particular bug. Comments such as "fixed!" or "Changed it." are unacceptable.
-@item
- If you apply a patch by someone else, include the name and email address in
- the log message. Since the ffmpeg-cvslog mailing list is publicly
- archived you should add some SPAM protection to the email address. Send an
- answer to ffmpeg-devel (or wherever you got the patch from) saying that
- you applied the patch.
-@item
- When applying patches that have been discussed (at length) on the mailing
- list, reference the thread in the log message.
-@item
- Do NOT commit to code actively maintained by others without permission.
- Send a patch to ffmpeg-devel instead. If no one answers within a reasonable
- timeframe (12h for build failures and security fixes, 3 days small changes,
- 1 week for big patches) then commit your patch if you think it is OK.
- Also note, the maintainer can simply ask for more time to review!
-@item
- Subscribe to the ffmpeg-cvslog mailing list. The diffs of all commits
- are sent there and reviewed by all the other developers. Bugs and possible
- improvements or general questions regarding commits are discussed there. We
- expect you to react if problems with your code are uncovered.
-@item
- Update the documentation if you change behavior or add features. If you are
- unsure how best to do this, send a patch to ffmpeg-devel, the documentation
- maintainer(s) will review and commit your stuff.
-@item
- Try to keep important discussions and requests (also) on the public
- developer mailing list, so that all developers can benefit from them.
-@item
- Never write to unallocated memory, never write over the end of arrays,
- always check values read from some untrusted source before using them
- as array index or other risky things.
-@item
- Remember to check if you need to bump versions for the specific libav
- parts (libavutil, libavcodec, libavformat) you are changing. You need
- to change the version integer.
- Incrementing the first component means no backward compatibility to
- previous versions (e.g. removal of a function from the public API).
- Incrementing the second component means backward compatible change
- (e.g. addition of a function to the public API or extension of an
- existing data structure).
- Incrementing the third component means a noteworthy binary compatible
- change (e.g. encoder bug fix that matters for the decoder).
-@item
- Compiler warnings indicate potential bugs or code with bad style. If a type of
- warning always points to correct and clean code, that warning should
- be disabled, not the code changed.
- Thus the remaining warnings can either be bugs or correct code.
- If it is a bug, the bug has to be fixed. If it is not, the code should
- be changed to not generate a warning unless that causes a slowdown
- or obfuscates the code.
-@item
- If you add a new file, give it a proper license header. Do not copy and
- paste it from a random place, use an existing file as template.
-@end enumerate
-
-We think our rules are not too hard. If you have comments, contact us.
-
-Note, these rules are mostly borrowed from the MPlayer project.
-
-@section Submitting patches
-
-First, (@pxref{Coding Rules}) above if you did not yet.
-
-When you submit your patch, try to send a unified diff (diff '-up'
-option). We cannot read other diffs :-)
-
-Also please do not submit a patch which contains several unrelated changes.
-Split it into separate, self-contained pieces. This does not mean splitting
-file by file. Instead, make the patch as small as possible while still
-keeping it as a logical unit that contains an individual change, even
-if it spans multiple files. This makes reviewing your patches much easier
-for us and greatly increases your chances of getting your patch applied.
-
-Run the regression tests before submitting a patch so that you can
-verify that there are no big problems.
-
-Patches should be posted as base64 encoded attachments (or any other
-encoding which ensures that the patch will not be trashed during
-transmission) to the ffmpeg-devel mailing list, see
-@url{http://lists.mplayerhq.hu/mailman/listinfo/ffmpeg-devel}
-
-It also helps quite a bit if you tell us what the patch does (for example
-'replaces lrint by lrintf'), and why (for example '*BSD isn't C99 compliant
-and has no lrint()')
-
-Also please if you send several patches, send each patch as a separate mail,
-do not attach several unrelated patches to the same mail.
-
-@section New codecs or formats checklist
-
-@enumerate
-@item
- Did you use av_cold for codec initialization and close functions?
-@item
- Did you add a long_name under NULL_IF_CONFIG_SMALL to the AVCodec or
- AVInputFormat/AVOutputFormat struct?
-@item
- Did you bump the minor version number in @file{avcodec.h} or
- @file{avformat.h}?
-@item
- Did you register it in @file{allcodecs.c} or @file{allformats.c}?
-@item
- Did you add the CodecID to @file{avcodec.h}?
-@item
- If it has a fourcc, did you add it to @file{libavformat/riff.c},
- even if it is only a decoder?
-@item
- Did you add a rule to compile the appropriate files in the Makefile?
- Remember to do this even if you're just adding a format to a file that is
- already being compiled by some other rule, like a raw demuxer.
-@item
- Did you add an entry to the table of supported formats or codecs in the
- documentation?
-@item
- Did you add an entry in the Changelog?
-@item
- If it depends on a parser or a library, did you add that dependency in
- configure?
-@item
- Did you "svn add" the appropriate files before commiting?
-@end enumerate
-
-@section patch submission checklist
-
-@enumerate
-@item
- Do the regression tests pass with the patch applied?
-@item
- Does @code{make checkheaders} pass with the patch applied?
-@item
- Is the patch a unified diff?
-@item
- Is the patch against latest FFmpeg SVN?
-@item
- Are you subscribed to ffmpeg-dev?
- (the list is subscribers only due to spam)
-@item
- Have you checked that the changes are minimal, so that the same cannot be
- achieved with a smaller patch and/or simpler final code?
-@item
- If the change is to speed critical code, did you benchmark it?
-@item
- If you did any benchmarks, did you provide them in the mail?
-@item
- Have you checked that the patch does not introduce buffer overflows or
- other security issues?
-@item
- Did you test your decoder or demuxer against damaged data? If no, see
- tools/trasher and the noise bitstream filter. Your decoder or demuxer
- should not crash or end in a (near) infinite loop when fed damaged data.
-@item
- Is the patch created from the root of the source tree, so it can be
- applied with @code{patch -p0}?
-@item
- Does the patch not mix functional and cosmetic changes?
-@item
- Did you add tabs or trailing whitespace to the code? Both are forbidden.
-@item
- Is the patch attached to the email you send?
-@item
- Is the mime type of the patch correct? It should be text/x-diff or
- text/x-patch or at least text/plain and not application/octet-stream.
-@item
- If the patch fixes a bug, did you provide a verbose analysis of the bug?
-@item
- If the patch fixes a bug, did you provide enough information, including
- a sample, so the bug can be reproduced and the fix can be verified?
- Note please do not attach samples >100k to mails but rather provide a
- URL, you can upload to ftp://upload.ffmpeg.org
-@item
- Did you provide a verbose summary about what the patch does change?
-@item
- Did you provide a verbose explanation why it changes things like it does?
-@item
- Did you provide a verbose summary of the user visible advantages and
- disadvantages if the patch is applied?
-@item
- Did you provide an example so we can verify the new feature added by the
- patch easily?
-@item
- If you added a new file, did you insert a license header? It should be
- taken from FFmpeg, not randomly copied and pasted from somewhere else.
-@item
- You should maintain alphabetical order in alphabetically ordered lists as
- long as doing so does not break API/ABI compatibility.
-@item
- Lines with similar content should be aligned vertically when doing so
- improves readability.
-@item
- Did you provide a suggestion for a clear commit log message?
-@end enumerate
-
-@section Patch review process
-
-All patches posted to ffmpeg-devel will be reviewed, unless they contain a
-clear note that the patch is not for SVN.
-Reviews and comments will be posted as replies to the patch on the
-mailing list. The patch submitter then has to take care of every comment,
-that can be by resubmitting a changed patch or by discussion. Resubmitted
-patches will themselves be reviewed like any other patch. If at some point
-a patch passes review with no comments then it is approved, that can for
-simple and small patches happen immediately while large patches will generally
-have to be changed and reviewed many times before they are approved.
-After a patch is approved it will be committed to the repository.
-
-We will review all submitted patches, but sometimes we are quite busy so
-especially for large patches this can take several weeks.
-
-When resubmitting patches, please do not make any significant changes
-not related to the comments received during review. Such patches will
-be rejected. Instead, submit significant changes or new features as
-separate patches.
-
-@section Regression tests
-
-Before submitting a patch (or committing to the repository), you should at least
-test that you did not break anything.
-
-The regression tests build a synthetic video stream and a synthetic
-audio stream. These are then encoded and decoded with all codecs or
-formats. The CRC (or MD5) of each generated file is recorded in a
-result file. A 'diff' is launched to compare the reference results and
-the result file.
-
-The regression tests then go on to test the FFserver code with a
-limited set of streams. It is important that this step runs correctly
-as well.
-
-Run 'make test' to test all the codecs and formats.
-
-Run 'make fulltest' to test all the codecs, formats and FFserver.
-
-[Of course, some patches may change the results of the regression tests. In
-this case, the reference results of the regression tests shall be modified
-accordingly].
-
@bye
projects / ffmpeg / blobdiff