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\input texinfo @c -*- texinfo -*-
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@settitle General Documentation
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@titlepage
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@sp 7
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@center @titlefont{General Documentation}
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@sp 3
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@end titlepage
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@chapter external libraries
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FFmpeg can be hooked up with a number of external libraries to add support
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for more formats. None of them are used by default, their use has to be
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explicitly requested by passing the appropriate flags to @file{./configure}.
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@section AMR
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AMR comes in two different flavors, wideband and narrowband. FFmpeg can make
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use of the AMR wideband (floating-point mode) and the AMR narrowband
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(floating-point mode) reference decoders and encoders.
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Go to @url{http://www.penguin.cz/~utx/amr} and follow the instructions for
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installing the libraries. Then pass @code{--enable-libamr-nb} and/or
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@code{--enable-libamr-wb} to configure to enable the libraries.
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Note that libamr is copyrighted without any sort of license grant. This means
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that you can use it if you legally obtained it but you are not allowed to
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redistribute it in any way. @strong{Any FFmpeg binaries with libamr support
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you create are non-free and unredistributable!}
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@chapter Supported File Formats and Codecs
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You can use the @code{-formats} option to have an exhaustive list.
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@section File Formats
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FFmpeg supports the following file formats through the @code{libavformat}
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library:
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@multitable @columnfractions .4 .1 .1 .4
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@item Name @tab Encoding @tab Decoding @tab Comments
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@item 4xm                       @tab   @tab X
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    @tab 4X Technologies format, used in some games.
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@item Audio IFF (AIFF)          @tab X @tab X
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@item American Laser Games MM   @tab   @tab X
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    @tab Multimedia format used in games like Mad Dog McCree.
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@item 3GPP AMR                  @tab X @tab X
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@item ASF                       @tab X @tab X
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@item AVI                       @tab X @tab X
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@item AVISynth                  @tab   @tab X
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@item AVS                       @tab   @tab X
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    @tab Multimedia format used by the Creature Shock game.
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@item Beam Software SIFF        @tab   @tab X
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    @tab Audio and video format used in some games by Beam Software.
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@item Bethesda Softworks VID    @tab   @tab X
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    @tab Used in some games from Bethesda Softworks.
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@item Brute Force & Ignorance   @tab   @tab X
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    @tab Used in the game Flash Traffic: City of Angels.
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@item Interplay C93             @tab   @tab X
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    @tab Used in the game Cyberia from Interplay.
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@item Delphine Software International CIN @tab   @tab X
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    @tab Multimedia format used by Delphine Software games.
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@item CRC testing format        @tab X @tab
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@item Creative Voice            @tab X @tab X
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    @tab Created for the Sound Blaster Pro.
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@item CRYO APC                  @tab   @tab X
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    @tab Audio format used in some games by CRYO Interactive Entertainment.
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@item D-Cinema audio            @tab X @tab X
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@item DV video                  @tab X @tab X
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@item DXA                       @tab   @tab X
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    @tab This format is used in the non-Windows version of the Feeble Files
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         game and different game cutscenes repacked for use with ScummVM.
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@item Electronic Arts cdata  @tab    @tab X
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@item Electronic Arts Multimedia  @tab    @tab X
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    @tab Used in various EA games; files have extensions like WVE and UV2.
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@item FFM (FFserver live feed)  @tab X @tab X
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@item Flash (SWF)               @tab X @tab X
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@item Flash 9 (AVM2)            @tab X @tab X
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    @tab Only embedded audio is decoded.
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@item FLI/FLC/FLX animation     @tab   @tab X
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    @tab .fli/.flc files
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@item FLV                       @tab X @tab X
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    @tab Macromedia Flash video files
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@item framecrc testing format   @tab X @tab
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@item FunCom ISS                @tab   @tab X
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    @tab Audio format used in various games from FunCom like The Longest Journey.
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@item GIF Animation             @tab X @tab
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@item GXF                       @tab X @tab X
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    @tab General eXchange Format SMPTE 360M, used by Thomson Grass Valley
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         playout servers.
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@item id Cinematic              @tab   @tab X
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    @tab Used in Quake II.
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@item id RoQ                    @tab X @tab X
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    @tab Used in Quake III, Jedi Knight 2, other computer games.
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@item IFF                       @tab   @tab X
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    @tab Interchange File Format
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@item Interplay MVE             @tab   @tab X
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    @tab Format used in various Interplay computer games.
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@item LMLM4                     @tab   @tab X
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    @tab Used by Linux Media Labs MPEG-4 PCI boards
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@item Matroska                  @tab X @tab X
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@item Matroska audio            @tab X @tab
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@item MAXIS XA                  @tab   @tab X
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    @tab Used in Sim City 3000; file extension .xa.
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@item Monkey's Audio            @tab   @tab X
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@item Motion Pixels MVI         @tab   @tab X
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@item MOV/QuickTime/MP4         @tab X @tab X
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    @tab 3GP, 3GP2, PSP, iPod variants supported
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@item MP2                       @tab X @tab
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@item MP3                       @tab X @tab
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@item MPEG audio                @tab X @tab X
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@item MPEG-1 System             @tab X @tab X
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    @tab muxed audio and video, VCD format supported
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@item MPEG-PS (program stream)  @tab X @tab X
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    @tab also known as @code{VOB} file, SVCD and DVD format supported
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@item MPEG-TS (transport stream) @tab X @tab X
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    @tab also known as DVB Transport Stream
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@item MPEG-4                    @tab X @tab X
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    @tab MPEG-4 is a variant of QuickTime.
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@item MIME multipart JPEG       @tab X @tab
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@item MSN TCP webcam            @tab   @tab X
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    @tab Used by MSN Messenger webcam streams.
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@item MTV                       @tab   @tab X
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@item Musepack                  @tab   @tab X
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@item Musepack SV8              @tab   @tab X
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@item Material eXchange Format (MXF) @tab X @tab X
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    @tab SMPTE 377M, used by D-Cinema, broadcast industry.
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@item Material eXchange Format (MXF), D-10 Mapping @tab X @tab X
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    @tab SMPTE 386M, D-10/IMX Mapping.
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@item NC camera feed            @tab   @tab X
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    @tab NC (AVIP NC4600) camera streams
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@item Nullsoft Streaming Video  @tab   @tab X
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@item NuppelVideo               @tab   @tab X
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@item NUT                       @tab X @tab X
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    @tab NUT Open Container Format
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@item Ogg                       @tab X @tab X
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@item TechnoTrend PVA           @tab   @tab X
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    @tab Used by TechnoTrend DVB PCI boards.
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@item raw ADTS (AAC)            @tab X @tab X
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@item raw AC-3                  @tab X @tab X
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@item raw Chinese AVS video     @tab   @tab X
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@item raw CRI ADX               @tab X @tab X
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@item raw Dirac                 @tab X @tab X
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@item raw DNxHD                 @tab X @tab X
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@item raw DTS                   @tab X @tab X
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@item raw E-AC-3                @tab X @tab X
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@item raw FLAC                  @tab X @tab X
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@item raw GSM                   @tab   @tab X
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@item raw H.261                 @tab X @tab X
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@item raw H.263                 @tab X @tab X
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@item raw H.264                 @tab X @tab X
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@item raw Ingenient MJPEG       @tab   @tab X
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@item raw MJPEG                 @tab X @tab X
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@item raw MLP                   @tab   @tab X
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@item raw MPEG                  @tab   @tab X
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@item raw MPEG-1                @tab   @tab X
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@item raw MPEG-2                @tab   @tab X
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@item raw MPEG-4                @tab X @tab X
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@item raw NULL                  @tab X @tab
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@item raw video                 @tab X @tab X
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@item raw id RoQ                @tab X @tab
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@item raw Shorten               @tab   @tab X
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@item raw VC-1                  @tab   @tab X
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@item raw PCM A-law             @tab X @tab X
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@item raw PCM mu-law            @tab X @tab X
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@item raw PCM signed 8 bit      @tab X @tab X
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@item raw PCM signed 16 bit big-endian  @tab X @tab X
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@item raw PCM signed 16 bit little-endian  @tab X @tab X
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@item raw PCM signed 24 bit big-endian  @tab X @tab X
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@item raw PCM signed 24 bit little-endian  @tab X @tab X
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@item raw PCM signed 32 bit big-endian  @tab X @tab X
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@item raw PCM signed 32 bit little-endian  @tab X @tab X
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@item raw PCM unsigned 8 bit    @tab X @tab X
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@item raw PCM unsigned 16 bit big-endian  @tab X @tab X
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@item raw PCM unsigned 16 bit little-endian  @tab X @tab X
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@item raw PCM unsigned 24 bit big-endian  @tab X @tab X
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@item raw PCM unsigned 24 bit little-endian  @tab X @tab X
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@item raw PCM unsigned 32 bit big-endian  @tab X @tab X
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@item raw PCM unsigned 32 bit little-endian  @tab X @tab X
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@item raw PCM floating-point 32 bit big-endian  @tab X @tab X
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@item raw PCM floating-point 32 bit little-endian  @tab X @tab X
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@item raw PCM floating-point 64 bit big-endian  @tab X @tab X
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@item raw PCM floating-point 64 bit little-endian  @tab X @tab X
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@item RDT                       @tab   @tab X
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@item REDCODE R3D               @tab   @tab X
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    @tab File format used by RED Digital cameras, contains JPEG 2000 frames and PCM audio.
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@item RealMedia                 @tab X @tab X
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@item Redirector                @tab   @tab X
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@item Renderware TeXture Dictionary @tab   @tab X
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@item RL2                       @tab   @tab X
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    @tab Audio and video format used in some games by Entertainment Software Partners.
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@item RPL/ARMovie               @tab   @tab X
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@item RTP                       @tab   @tab X
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@item RTSP                      @tab   @tab X
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@item SDP                       @tab   @tab X
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@item Sega FILM/CPK             @tab   @tab X
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    @tab Used in many Sega Saturn console games.
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@item Sierra SOL                @tab   @tab X
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    @tab .sol files used in Sierra Online games.
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@item Sierra VMD                @tab   @tab X
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    @tab Used in Sierra CD-ROM games.
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@item Smacker                   @tab   @tab X
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    @tab Multimedia format used by many games.
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@item Sony OpenMG (OMA)         @tab   @tab X
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    @tab Audio format used in Sony Sonic Stage and Sony Vegas.
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@item Sony PlayStation STR      @tab   @tab X
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@item SUN AU format             @tab X @tab X
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@item THP                       @tab   @tab X
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    @tab Used on the Nintendo GameCube.
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@item Tiertex Limited SEQ       @tab   @tab X
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    @tab Tiertex .seq files used in the DOS CD-ROM version of the game Flashback.
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@item True Audio                @tab   @tab X
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@item VC-1 test bitstream       @tab X @tab X
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@item WAV                       @tab X @tab X
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@item WavPack                   @tab   @tab X
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@item Wing Commander III movie  @tab   @tab X
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    @tab Multimedia format used in Origin's Wing Commander III computer game.
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@item Westwood Studios audio    @tab   @tab X
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    @tab Multimedia format used in Westwood Studios games.
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@item Westwood Studios VQA      @tab   @tab X
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    @tab Multimedia format used in Westwood Studios games.
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@item YUV4MPEG pipe             @tab X @tab X
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@end multitable
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@code{X} means that encoding (resp. decoding) is supported.
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@section Image Formats
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FFmpeg can read and write images for each frame of a video sequence. The
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following image formats are supported:
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@multitable @columnfractions .4 .1 .1 .4
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@item Name @tab Encoding @tab Decoding @tab Comments
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@item .Y.U.V       @tab X @tab X
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    @tab one raw file per component
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@item animated GIF @tab X @tab X
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    @tab Only uncompressed GIFs are generated.
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@item JPEG         @tab X @tab X
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    @tab Progressive JPEG is not supported.
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@item JPEG 2000    @tab   @tab E
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    @tab decoding supported through external library libopenjpeg
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@item PAM          @tab X @tab X
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    @tab PAM is a PNM extension with alpha support.
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@item PCX          @tab   @tab X
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    @tab PC Paintbrush
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@item PGM          @tab X @tab X
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    @tab Portable GrayMap image
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@item PGMYUV       @tab X @tab X
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    @tab PGM with U and V components in YUV 4:2:0
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@item PNG          @tab X @tab X
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    @tab 2/4 bpp not supported yet
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@item PPM          @tab X @tab X
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    @tab Portable PixelMap image
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@item PTX          @tab   @tab X
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    @tab V.Flash PTX format
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@item RAS          @tab   @tab X
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    @tab Sun Rasterfile
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@item SGI          @tab X @tab X
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    @tab SGI RGB image format
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@item Targa        @tab   @tab X
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    @tab Targa (.TGA) image format
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@item TIFF         @tab X @tab X
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    @tab YUV, JPEG and some extension is not supported yet.
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@end multitable
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@code{X} means that encoding (resp. decoding) is supported.
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@code{E} means that support is provided through an external library.
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@section Video Codecs
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@multitable @columnfractions .4 .1 .1 .4
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@item Name @tab Encoding @tab Decoding @tab Comments
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@item 4X Video               @tab     @tab  X
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    @tab Used in certain computer games.
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@item American Laser Games MM  @tab    @tab X
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    @tab Used in games like Mad Dog McCree.
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@item AMV                    @tab     @tab  X
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    @tab Used in Chinese MP3 players.
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@item Apple Animation        @tab  X  @tab  X
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    @tab fourcc: 'rle '
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@item Apple Graphics         @tab     @tab  X
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    @tab fourcc: 'smc '
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@item Apple MJPEG-B          @tab     @tab  X
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@item Apple QuickDraw        @tab     @tab  X
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    @tab fourcc: qdrw
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@item Apple Video            @tab     @tab  X
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    @tab fourcc: rpza
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@item Asus v1                @tab  X  @tab  X
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    @tab fourcc: ASV1
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@item Asus v2                @tab  X  @tab  X
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    @tab fourcc: ASV2
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@item ATI VCR1               @tab     @tab  X
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    @tab fourcc: VCR1
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@item ATI VCR2               @tab     @tab  X
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    @tab fourcc: VCR2
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@item Autodesk RLE           @tab     @tab  X
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    @tab fourcc: AASC
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@item AVID DNxHD             @tab   X @tab  X
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    @tab aka SMPTE VC3
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@item AVS video              @tab     @tab  X
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    @tab Video encoding used by the Creature Shock game.
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@item Bethsoft VID           @tab     @tab  X
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    @tab Used in some games from Bethesda Softworks.
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@item C93 video              @tab     @tab  X
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    @tab Codec used in Cyberia game.
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@item CamStudio              @tab     @tab  X
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    @tab fourcc: CSCD
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@item Cin video              @tab     @tab  X
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    @tab Codec used in Delphine Software games.
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@item Cinepak                @tab     @tab  X
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@item Cirrus Logic AccuPak   @tab     @tab  X
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    @tab fourcc: CLJR
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@item Creative YUV           @tab     @tab  X
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    @tab fourcc: CYUV
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@item Dirac                  @tab  E  @tab  E
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    @tab supported through external libdirac/libschroedinger libraries
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@item Duck TrueMotion v1     @tab     @tab  X
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    @tab fourcc: DUCK
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@item Duck TrueMotion v2     @tab     @tab  X
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    @tab fourcc: TM20
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@item DV                     @tab  X  @tab  X
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@item DXA Video              @tab     @tab  X
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    @tab Codec originally used in Feeble Files game.
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@item Electronic Arts CMV    @tab     @tab  X
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    @tab Used in NHL 95 game.
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@item Electronic Arts TGV    @tab     @tab  X
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@item Electronic Arts TGQ    @tab     @tab  X
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@item Electronic Arts TQI    @tab     @tab  X
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@item FFmpeg Video 1         @tab  X  @tab  X
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    @tab experimental lossless codec (fourcc: FFV1)
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@item Flash Screen Video     @tab  X  @tab  X
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    @tab fourcc: FSV1
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@item FLIC video             @tab     @tab  X
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@item FLV                    @tab  X  @tab  X
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    @tab Sorenson H.263 used in Flash
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@item Fraps FPS1             @tab     @tab  X
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@item H.261                  @tab  X  @tab  X
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@item H.263(+)               @tab  X  @tab  X
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    @tab also known as RealVideo 1.0
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@item H.264                  @tab  E  @tab  X
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    @tab encoding supported through external library libx264
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@item HuffYUV                @tab  X  @tab  X
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@item IBM Ultimotion         @tab     @tab  X
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    @tab fourcc: ULTI
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@item id Cinematic video     @tab     @tab  X
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    @tab Used in Quake II.
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@item id RoQ                 @tab  X  @tab  X
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    @tab Used in Quake III, Jedi Knight 2, other computer games.
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@item Intel Indeo 3          @tab     @tab  X
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@item Interplay Video        @tab     @tab  X
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    @tab Used in Interplay .MVE files.
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@item JPEG-LS                @tab  X  @tab  X
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    @tab fourcc: MJLS, lossless and near-lossless is supported.
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@item KMVC                   @tab     @tab  X
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    @tab Codec used in Worms games.
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@item LOCO                   @tab     @tab  X
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@item lossless MJPEG         @tab  X  @tab  X
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@item Microsoft RLE          @tab     @tab  X
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@item Microsoft Video-1      @tab     @tab  X
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@item Mimic                  @tab     @tab  X
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    @tab Used in MSN Messenger Webcam streams.
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@item Miro VideoXL           @tab     @tab  X
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    @tab fourcc: VIXL
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@item MJPEG                  @tab  X  @tab  X
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@item Motion Pixels Video    @tab     @tab  X
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@item MPEG-1                 @tab  X  @tab  X
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@item MPEG-2                 @tab  X  @tab  X
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@item MPEG-4                 @tab  X  @tab  X
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@item MSMPEG4 V1             @tab  X  @tab  X
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@item MSMPEG4 V2             @tab  X  @tab  X
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@item MSMPEG4 V3             @tab  X  @tab  X
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@item MSZH                   @tab     @tab  X
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    @tab Part of LCL
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@item On2 VP3                @tab     @tab  X
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    @tab still experimental
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@item On2 VP5                @tab     @tab  X
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    @tab fourcc: VP50
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@item On2 VP6                @tab     @tab  X
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    @tab fourcc: VP60,VP61,VP62
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@item planar RGB             @tab     @tab  X
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    @tab fourcc: 8BPS
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@item QPEG                   @tab     @tab  X
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    @tab fourccs: QPEG, Q1.0, Q1.1
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@item RealVideo 1.0          @tab  X  @tab  X
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@item RealVideo 2.0          @tab  X  @tab  X
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@item RealVideo 3.0          @tab     @tab  X
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    @tab still far from ideal
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@item RealVideo 4.0          @tab     @tab  X
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@item Renderware TXD         @tab     @tab  X
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    @tab Texture dictionaries used by the Renderware Engine.
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@item RTjpeg                 @tab     @tab  X
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    @tab Video encoding used in NuppelVideo files.
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@item Smacker video          @tab     @tab  X
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    @tab Video encoding used in Smacker.
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@item Snow                   @tab  X  @tab  X
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    @tab experimental wavelet codec (fourcc: SNOW)
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@item Sony PlayStation MDEC  @tab     @tab  X
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@item Sorenson Video 1       @tab  X  @tab  X
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    @tab fourcc: SVQ1
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@item Sorenson Video 3       @tab     @tab  X
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    @tab fourcc: SVQ3
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@item Sunplus MJPEG          @tab     @tab  X
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    @tab fourcc: SP5X
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@item TechSmith Camtasia     @tab     @tab  X
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    @tab fourcc: TSCC
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@item Theora                 @tab  E  @tab  X
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    @tab encoding supported through external library libtheora
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@item THP                    @tab     @tab  X
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    @tab Used on the Nintendo GameCube.
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@item Tiertex Seq video      @tab     @tab  X
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    @tab Codec used in DOS CD-ROM FlashBack game.
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@item VC-1                   @tab     @tab  X
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@item VMD Video              @tab     @tab  X
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    @tab Used in Sierra VMD files.
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@item VMware Video           @tab     @tab  X
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    @tab Codec used in videos captured by VMware.
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@item Westwood VQA           @tab     @tab  X
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@item Winnov WNV1            @tab     @tab  X
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@item WMV7                   @tab  X  @tab  X
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@item WMV8                   @tab  X  @tab  X
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@item WMV9                   @tab     @tab  X
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    @tab not completely working
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@item Xan/WC3                @tab     @tab  X
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    @tab Used in Wing Commander III .MVE files.
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@item YAMAHA SMAF            @tab  X  @tab  X
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@item ZLIB                   @tab  X  @tab  X
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    @tab part of LCL, encoder experimental
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@item ZMBV                   @tab   X @tab  X
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    @tab Encoder works only in PAL8.
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@end multitable
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@code{X} means that encoding (resp. decoding) is supported.
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@code{E} means that support is provided through an external library.
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@section Audio Codecs
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@multitable @columnfractions .4 .1 .1 .4
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@item Name @tab Encoding @tab Decoding @tab Comments
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@item 4X IMA ADPCM           @tab     @tab  X
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@item 8SVX audio             @tab     @tab  X
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@item AAC                    @tab  E  @tab  X
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    @tab encoding supported through external library libfaac
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@item AC-3                   @tab IX  @tab IX
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@item AMR-NB                 @tab  E  @tab  E
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    @tab supported through external library libamrnb
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@item AMR-WB                 @tab  E  @tab  E
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    @tab supported through external library libamrwb
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@item AMV IMA ADPCM          @tab     @tab  X
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    @tab Used in AMV files
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@item Apple lossless audio   @tab  X  @tab  X
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    @tab QuickTime fourcc 'alac'
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@item Apple MACE 3           @tab     @tab  X
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@item Apple MACE 6           @tab     @tab  X
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@item ATRAC 3                @tab     @tab  X
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@item CD-ROM XA ADPCM        @tab     @tab  X
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@item Cin audio              @tab     @tab  X
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    @tab Codec used in Delphine Software International games.
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@item Creative ADPCM         @tab     @tab  X
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    @tab 16 -> 4, 8 -> 4, 8 -> 3, 8 -> 2
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@item CRI ADX ADPCM          @tab  X  @tab  X
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    @tab Used in Sega Dreamcast games.
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@item DSP Group TrueSpeech   @tab     @tab  X
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@item DTS Coherent Audio     @tab     @tab  X
468
@item Duck DK3 IMA ADPCM     @tab     @tab  X
469
    @tab Used in some Sega Saturn console games.
470
@item Duck DK4 IMA ADPCM     @tab     @tab  X
471
    @tab Used in some Sega Saturn console games.
472
@item DV audio               @tab     @tab  X
473
@item Electronic Arts ADPCM  @tab     @tab  X
474
    @tab Used in various EA titles.
475
@item Enhanced AC-3          @tab     @tab  X
476
@item FLAC lossless audio    @tab IX  @tab  X
477
@item G.726  ADPCM           @tab  X  @tab  X
478
@item GSM                    @tab  E  @tab  E
479
    @tab supported through external library libgsm
480
@item GSM_MS                 @tab  E  @tab  E
481
    @tab supported through external library libgsm
482
@item id RoQ DPCM            @tab  X  @tab  X
483
    @tab Used in Quake III, Jedi Knight 2, other computer games.
484
@item Intel Music Coder      @tab     @tab  X
485
@item Interplay MVE DPCM     @tab     @tab  X
486
    @tab Used in various Interplay computer games.
487
@item ISS IMA ADPCM          @tab     @tab  X
488
    @tab Used in FunCom games.
489
@item MAXIS EA ADPCM         @tab     @tab  X
490
    @tab Used in Sim City 3000.
491
@item Microsoft ADPCM        @tab  X  @tab  X
492
@item MLP/TrueHD             @tab     @tab  X
493
    @tab Used in DVD-Audio and Blu-Ray discs.
494
@item Monkey's Audio         @tab     @tab  X
495
    @tab Only versions 3.97-3.99 are supported.
496
@item MPEG audio layer 3     @tab  E  @tab IX
497
    @tab encoding supported through external library LAME
498
@item MPEG audio layer 2     @tab IX  @tab IX
499
@item MS IMA ADPCM           @tab  X  @tab  X
500
@item Musepack               @tab     @tab  X
501
    @tab SV7 and SV8 are supported.
502
@item Nellymoser ASAO        @tab  X  @tab  X
503
@item QCELP / PureVoice      @tab     @tab  X
504
@item Qdesign QDM2           @tab     @tab  X
505
    @tab There are still some distortions.
506
@item QT IMA ADPCM           @tab  X  @tab  X
507
@item RA144                  @tab     @tab  X
508
    @tab Real 14400 bit/s codec
509
@item RA288                  @tab     @tab  X
510
    @tab Real 28800 bit/s codec
511
@item RADnet                 @tab IX  @tab IX
512
    @tab Real low bitrate AC-3 codec
513
@item Real COOK              @tab     @tab  X
514
    @tab All versions except 5.1 are supported.
515
@item Shorten                @tab     @tab  X
516
@item Sierra Online DPCM     @tab     @tab  X
517
    @tab Used in Sierra Online game audio files.
518
@item Smacker audio          @tab     @tab  X
519
@item SMJPEG IMA ADPCM       @tab     @tab  X
520
    @tab Used in certain Loki game ports.
521
@item Sonic                  @tab  X  @tab  X
522
    @tab experimental codec
523
@item Sonic lossless         @tab  X  @tab  X
524
    @tab experimental codec
525
@item Speex                  @tab     @tab  E
526
    @tab supported through external library libspeex
527
@item THP ADPCM              @tab     @tab  X
528
    @tab Used on the Nintendo GameCube.
529
@item True Audio (TTA)       @tab     @tab  X
530
@item Vorbis                 @tab  X  @tab  X
531
@item WavPack                @tab     @tab  X
532
@item Westwood Studios IMA ADPCM @tab     @tab  X
533
    @tab Used in Westwood Studios games like Command and Conquer.
534
@item WMA v1/v2              @tab  X  @tab  X
535
@item Xan DPCM               @tab     @tab  X
536
    @tab Used in Origin's Wing Commander IV AVI files.
537
@end multitable
538

    
539
@code{X} means that encoding (resp. decoding) is supported.
540

    
541
@code{E} means that support is provided through an external library.
542

    
543
@code{I} means that an integer-only version is available, too (ensures high
544
performance on systems without hardware floating point support).
545

    
546
@section Subtitle Formats
547

    
548
@multitable @columnfractions .4 .1 .1 .1 .1 .1
549
@item Name @tab Muxing @tab Demuxing @tab Encoding @tab Decoding
550
@item SSA/ASS      @tab X @tab X
551
@item DVB          @tab X @tab X @tab X @tab X
552
@item DVD          @tab X @tab X @tab X @tab X
553
@item XSUB         @tab   @tab   @tab   @tab X
554
@end multitable
555

    
556
@code{X} means that the feature is supported.
557

    
558
@section Network Protocols
559

    
560
@multitable @columnfractions .4 .1 .1 .1 .1 .1
561
@item Name         @tab Support
562
@item file         @tab X
563
@item Gopher       @tab X
564
@item HTTP         @tab X
565
@item pipe         @tab X
566
@item RTP          @tab X
567
@item TCP          @tab X
568
@item UDP          @tab X
569
@end multitable
570

    
571
@code{X} means that the protocol is supported.
572

    
573

    
574
@chapter Platform Specific information
575

    
576
@section BSD
577

    
578
BSD make will not build FFmpeg, you need to install and use GNU Make
579
(@file{gmake}).
580

    
581
@section Windows
582

    
583
To get help and instructions for building FFmpeg under Windows, check out
584
the FFmpeg Windows Help Forum at
585
@url{http://ffmpeg.arrozcru.org/}.
586

    
587
@subsection Native Windows compilation
588

    
589
FFmpeg can be built to run natively on Windows using the MinGW tools. Install
590
the latest versions of MSYS and MinGW from @url{http://www.mingw.org/}.
591
You can find detailed installation
592
instructions in the download section and the FAQ.
593

    
594
FFmpeg does not build out-of-the-box with the packages the automated MinGW
595
installer provides. It also requires coreutils to be installed and many other
596
packages updated to the latest version. The minimum version for some packages
597
are listed below:
598

    
599
@itemize
600
@item bash 3.1
601
@item msys-make 3.81-2 (note: not mingw32-make)
602
@item w32api 3.13
603
@item mingw-runtime 3.15
604
@end itemize
605

    
606
You will also need to pass @code{-fno-common} to the compiler to work around
607
a GCC bug (see @url{http://gcc.gnu.org/bugzilla/show_bug.cgi?id=37216}).
608

    
609
Within the MSYS shell, configure and make with:
610

    
611
@example
612
./configure --enable-memalign-hack --extra-cflags=-fno-common
613
make
614
make install
615
@end example
616

    
617
This will install @file{ffmpeg.exe} along with many other development files
618
to @file{/usr/local}. You may specify another install path using the
619
@code{--prefix} option in @file{configure}.
620

    
621
Notes:
622

    
623
@itemize
624

    
625
@item In order to compile vhooks, you must have a POSIX-compliant libdl in
626
your MinGW system. Get dlfcn-win32 from
627
@url{http://code.google.com/p/dlfcn-win32}.
628

    
629
@item In order to compile FFplay, you must have the MinGW development library
630
of SDL. Get it from @url{http://www.libsdl.org}.
631
Edit the @file{bin/sdl-config} script so that it points to the correct prefix
632
where SDL was installed. Verify that @file{sdl-config} can be launched from
633
the MSYS command line.
634

    
635
@item By using @code{./configure --enable-shared} when configuring FFmpeg,
636
you can build libavutil, libavcodec and libavformat as DLLs.
637

    
638
@end itemize
639

    
640
@subsection Microsoft Visual C++ compatibility
641

    
642
As stated in the FAQ, FFmpeg will not compile under MSVC++. However, if you
643
want to use the libav* libraries in your own applications, you can still
644
compile those applications using MSVC++. But the libav* libraries you link
645
to @emph{must} be built with MinGW. However, you will not be able to debug
646
inside the libav* libraries, since MSVC++ does not recognize the debug
647
symbols generated by GCC.
648
We strongly recommend you to move over from MSVC++ to MinGW tools.
649

    
650
This description of how to use the FFmpeg libraries with MSVC++ is based on
651
Microsoft Visual C++ 2005 Express Edition. If you have a different version,
652
you might have to modify the procedures slightly.
653

    
654
@subsubsection Using static libraries
655

    
656
Assuming you have just built and installed FFmpeg in @file{/usr/local}.
657

    
658
@enumerate
659

    
660
@item Create a new console application ("File / New / Project") and then
661
select "Win32 Console Application". On the appropriate page of the
662
Application Wizard, uncheck the "Precompiled headers" option.
663

    
664
@item Write the source code for your application, or, for testing, just
665
copy the code from an existing sample application into the source file
666
that MSVC++ has already created for you. For example, you can copy
667
@file{output_example.c} from the FFmpeg distribution.
668

    
669
@item Open the "Project / Properties" dialog box. In the "Configuration"
670
combo box, select "All Configurations" so that the changes you make will
671
affect both debug and release builds. In the tree view on the left hand
672
side, select "C/C++ / General", then edit the "Additional Include
673
Directories" setting to contain the path where the FFmpeg includes were
674
installed (i.e. @file{c:\msys\1.0\local\include}).
675
Do not add MinGW's include directory here, or the include files will
676
conflict with MSVC's.
677

    
678
@item Still in the "Project / Properties" dialog box, select
679
"Linker / General" from the tree view and edit the
680
"Additional Library Directories" setting to contain the @file{lib}
681
directory where FFmpeg was installed (i.e. @file{c:\msys\1.0\local\lib}),
682
the directory where MinGW libs are installed (i.e. @file{c:\mingw\lib}),
683
and the directory where MinGW's GCC libs are installed
684
(i.e. @file{C:\mingw\lib\gcc\mingw32\4.2.1-sjlj}). Then select
685
"Linker / Input" from the tree view, and add the files @file{libavformat.a},
686
@file{libavcodec.a}, @file{libavutil.a}, @file{libmingwex.a},
687
@file{libgcc.a}, and any other libraries you used (i.e. @file{libz.a})
688
to the end of "Additional Dependencies".
689

    
690
@item Now, select "C/C++ / Code Generation" from the tree view. Select
691
"Debug" in the "Configuration" combo box. Make sure that "Runtime
692
Library" is set to "Multi-threaded Debug DLL". Then, select "Release" in
693
the "Configuration" combo box and make sure that "Runtime Library" is
694
set to "Multi-threaded DLL".
695

    
696
@item Click "OK" to close the "Project / Properties" dialog box.
697

    
698
@item MSVC++ lacks some C99 header files that are fundamental for FFmpeg.
699
Get msinttypes from @url{http://code.google.com/p/msinttypes/downloads/list}
700
and install it in MSVC++'s include directory
701
(i.e. @file{C:\Program Files\Microsoft Visual Studio 8\VC\include}).
702

    
703
@item MSVC++ also does not understand the @code{inline} keyword used by
704
FFmpeg, so you must add this line before @code{#include}ing libav*:
705
@example
706
#define inline _inline
707
@end example
708

    
709
@item Build your application, everything should work.
710

    
711
@end enumerate
712

    
713
@subsubsection Using shared libraries
714

    
715
This is how to create DLL and LIB files that are compatible with MSVC++:
716

    
717
@enumerate
718

    
719
@item Add a call to @file{vcvars32.bat} (which sets up the environment
720
variables for the Visual C++ tools) as the first line of @file{msys.bat}.
721
The standard location for @file{vcvars32.bat} is
722
@file{C:\Program Files\Microsoft Visual Studio 8\VC\bin\vcvars32.bat},
723
and the standard location for @file{msys.bat} is @file{C:\msys\1.0\msys.bat}.
724
If this corresponds to your setup, add the following line as the first line
725
of @file{msys.bat}:
726

    
727
@example
728
call "C:\Program Files\Microsoft Visual Studio 8\VC\bin\vcvars32.bat"
729
@end example
730

    
731
Alternatively, you may start the @file{Visual Studio 2005 Command Prompt},
732
and run @file{c:\msys\1.0\msys.bat} from there.
733

    
734
@item Within the MSYS shell, run @code{lib.exe}. If you get a help message
735
from @file{Microsoft (R) Library Manager}, this means your environment
736
variables are set up correctly, the @file{Microsoft (R) Library Manager}
737
is on the path and will be used by FFmpeg to create
738
MSVC++-compatible import libraries.
739

    
740
@item Build FFmpeg with
741

    
742
@example
743
./configure --enable-shared --enable-memalign-hack
744
make
745
make install
746
@end example
747

    
748
Your install path (@file{/usr/local/} by default) should now have the
749
necessary DLL and LIB files under the @file{bin} directory.
750

    
751
@end enumerate
752

    
753
To use those files with MSVC++, do the same as you would do with
754
the static libraries, as described above. But in Step 4,
755
you should only need to add the directory where the LIB files are installed
756
(i.e. @file{c:\msys\usr\local\bin}). This is not a typo, the LIB files are
757
installed in the @file{bin} directory. And instead of adding @file{libxx.a}
758
files, you should add @file{avcodec.lib}, @file{avformat.lib}, and
759
@file{avutil.lib}. There should be no need for @file{libmingwex.a},
760
@file{libgcc.a}, and @file{wsock32.lib}, nor any other external library
761
statically linked into the DLLs. The @file{bin} directory contains a bunch
762
of DLL files, but the ones that are actually used to run your application
763
are the ones with a major version number in their filenames
764
(i.e. @file{avcodec-51.dll}).
765

    
766
@subsection Cross compilation for Windows with Linux
767

    
768
You must use the MinGW cross compilation tools available at
769
@url{http://www.mingw.org/}.
770

    
771
Then configure FFmpeg with the following options:
772
@example
773
./configure --target-os=mingw32 --cross-prefix=i386-mingw32msvc-
774
@end example
775
(you can change the cross-prefix according to the prefix chosen for the
776
MinGW tools).
777

    
778
Then you can easily test FFmpeg with Wine
779
(@url{http://www.winehq.com/}).
780

    
781
@subsection Compilation under Cygwin
782

    
783
The main issue with the 1.5.x Cygwin versions is that newlib, its C library,
784
does not contain llrint().  You need to upgrade to the unstable 1.7.x versions,
785
or leverage the implementation in MinGW (as explained below).
786

    
787
Just install your Cygwin with all the "Base" packages, plus the
788
following "Devel" ones:
789
@example
790
binutils, gcc-core, make, subversion, mingw-runtime, diffutils
791
@end example
792

    
793
The experimental gcc4 package is still buggy, hence please
794
use the official gcc 3.4.4 or a 4.2.x compiled from source by yourself.
795

    
796
Install the current binutils-20080624-2 as they work fine (the old
797
binutils-20060709-1 proved buggy on shared builds).
798

    
799
Then create a small library that just contains llrint():
800

    
801
@example
802
ar x /usr/lib/mingw/libmingwex.a llrint.o
803
ar cq /usr/local/lib/libllrint.a llrint.o
804
@end example
805

    
806
Then run
807

    
808
@example
809
./configure --enable-static --disable-shared  --extra-ldflags='-L /usr/local/lib' --extra-libs='-l llrint'
810
@end example
811

    
812
to make a static build or
813

    
814
@example
815
./configure --enable-shared --disable-static  --extra-ldflags='-L /usr/local/lib' --extra-libs='-l llrint'
816
@end example
817

    
818
to build shared libraries.
819

    
820
If you want to build FFmpeg with additional libraries, download Cygwin
821
"Devel" packages for Ogg and Vorbis from any Cygwin packages repository:
822
@example
823
libogg-devel, libvorbis-devel
824
@end example
825

    
826
These library packages are only available from Cygwin Ports
827
(@url{http://sourceware.org/cygwinports/}) :
828

    
829
@example
830
yasm, libSDL-devel, libdirac-devel, libfaac-devel, libfaad-devel, libgsm-devel,
831
libmp3lame-devel, libschroedinger1.0-devel, speex-devel, libtheora-devel,
832
libxvidcore-devel
833
@end example
834

    
835
The recommendation for libnut and x264 is to build them from source by
836
yourself, as they evolve too quickly for Cygwin Ports to be up to date.
837

    
838
Cygwin 1.7.x has IPv6 support. You can add IPv6 to Cygwin 1.5.x by means
839
of the @code{libgetaddrinfo-devel} package, available at Cygwin Ports.
840

    
841
@subsection Crosscompilation for Windows under Cygwin
842

    
843
With Cygwin you can create Windows binaries that do not need the cygwin1.dll.
844

    
845
Just install your Cygwin as explained before, plus these additional
846
"Devel" packages:
847
@example
848
gcc-mingw-core, mingw-runtime, mingw-zlib
849
@end example
850

    
851
and add some special flags to your configure invocation.
852

    
853
For a static build run
854
@example
855
./configure --target-os=mingw32 --enable-memalign-hack --enable-static --disable-shared --extra-cflags=-mno-cygwin --extra-libs=-mno-cygwin
856
@end example
857

    
858
and for a build with shared libraries
859
@example
860
./configure --target-os=mingw32 --enable-memalign-hack --enable-shared --disable-static --extra-cflags=-mno-cygwin --extra-libs=-mno-cygwin
861
@end example
862

    
863
@section BeOS
864

    
865
BeOS support is broken in mysterious ways.
866

    
867
@section OS/2
868

    
869
For information about compiling FFmpeg on OS/2 see
870
@url{http://www.edm2.com/index.php/FFmpeg}.
871

    
872
@chapter Developers Guide
873

    
874
@section API
875
@itemize @bullet
876
@item libavcodec is the library containing the codecs (both encoding and
877
decoding). Look at @file{libavcodec/apiexample.c} to see how to use it.
878

    
879
@item libavformat is the library containing the file format handling (mux and
880
demux code for several formats). Look at @file{ffplay.c} to use it in a
881
player. See @file{output_example.c} to use it to generate audio or video
882
streams.
883

    
884
@end itemize
885

    
886
@section Integrating libavcodec or libavformat in your program
887

    
888
You can integrate all the source code of the libraries to link them
889
statically to avoid any version problem. All you need is to provide a
890
'config.mak' and a 'config.h' in the parent directory. See the defines
891
generated by ./configure to understand what is needed.
892

    
893
You can use libavcodec or libavformat in your commercial program, but
894
@emph{any patch you make must be published}. The best way to proceed is
895
to send your patches to the FFmpeg mailing list.
896

    
897
@node Coding Rules
898
@section Coding Rules
899

    
900
FFmpeg is programmed in the ISO C90 language with a few additional
901
features from ISO C99, namely:
902
@itemize @bullet
903
@item
904
the @samp{inline} keyword;
905
@item
906
@samp{//} comments;
907
@item
908
designated struct initializers (@samp{struct s x = @{ .i = 17 @};})
909
@item
910
compound literals (@samp{x = (struct s) @{ 17, 23 @};})
911
@end itemize
912

    
913
These features are supported by all compilers we care about, so we will not
914
accept patches to remove their use unless they absolutely do not impair
915
clarity and performance.
916

    
917
All code must compile with GCC 2.95 and GCC 3.3. Currently, FFmpeg also
918
compiles with several other compilers, such as the Compaq ccc compiler
919
or Sun Studio 9, and we would like to keep it that way unless it would
920
be exceedingly involved. To ensure compatibility, please do not use any
921
additional C99 features or GCC extensions. Especially watch out for:
922
@itemize @bullet
923
@item
924
mixing statements and declarations;
925
@item
926
@samp{long long} (use @samp{int64_t} instead);
927
@item
928
@samp{__attribute__} not protected by @samp{#ifdef __GNUC__} or similar;
929
@item
930
GCC statement expressions (@samp{(x = (@{ int y = 4; y; @})}).
931
@end itemize
932

    
933
Indent size is 4.
934
The presentation is the one specified by 'indent -i4 -kr -nut'.
935
The TAB character is forbidden outside of Makefiles as is any
936
form of trailing whitespace. Commits containing either will be
937
rejected by the Subversion repository.
938

    
939
The main priority in FFmpeg is simplicity and small code size in order to
940
minimize the bug count.
941

    
942
Comments: Use the JavaDoc/Doxygen
943
format (see examples below) so that code documentation
944
can be generated automatically. All nontrivial functions should have a comment
945
above them explaining what the function does, even if it is just one sentence.
946
All structures and their member variables should be documented, too.
947
@example
948
/**
949
 * @@file mpeg.c
950
 * MPEG codec.
951
 * @@author ...
952
 */
953

    
954
/**
955
 * Summary sentence.
956
 * more text ...
957
 * ...
958
 */
959
typedef struct Foobar@{
960
    int var1; /**< var1 description */
961
    int var2; ///< var2 description
962
    /** var3 description */
963
    int var3;
964
@} Foobar;
965

    
966
/**
967
 * Summary sentence.
968
 * more text ...
969
 * ...
970
 * @@param my_parameter description of my_parameter
971
 * @@return return value description
972
 */
973
int myfunc(int my_parameter)
974
...
975
@end example
976

    
977
fprintf and printf are forbidden in libavformat and libavcodec,
978
please use av_log() instead.
979

    
980
Casts should be used only when necessary. Unneeded parentheses
981
should also be avoided if they don't make the code easier to understand.
982

    
983
@section Development Policy
984

    
985
@enumerate
986
@item
987
   Contributions should be licensed under the LGPL 2.1, including an
988
   "or any later version" clause, or the MIT license.  GPL 2 including
989
   an "or any later version" clause is also acceptable, but LGPL is
990
   preferred.
991
@item
992
   You must not commit code which breaks FFmpeg! (Meaning unfinished but
993
   enabled code which breaks compilation or compiles but does not work or
994
   breaks the regression tests)
995
   You can commit unfinished stuff (for testing etc), but it must be disabled
996
   (#ifdef etc) by default so it does not interfere with other developers'
997
   work.
998
@item
999
   You do not have to over-test things. If it works for you, and you think it
1000
   should work for others, then commit. If your code has problems
1001
   (portability, triggers compiler bugs, unusual environment etc) they will be
1002
   reported and eventually fixed.
1003
@item
1004
   Do not commit unrelated changes together, split them into self-contained
1005
   pieces. Also do not forget that if part B depends on part A, but A does not
1006
   depend on B, then A can and should be committed first and separate from B.
1007
   Keeping changes well split into self-contained parts makes reviewing and
1008
   understanding them on the commit log mailing list easier. This also helps
1009
   in case of debugging later on.
1010
   Also if you have doubts about splitting or not splitting, do not hesitate to
1011
   ask/discuss it on the developer mailing list.
1012
@item
1013
   Do not change behavior of the program (renaming options etc) without
1014
   first discussing it on the ffmpeg-devel mailing list. Do not remove
1015
   functionality from the code. Just improve!
1016

    
1017
   Note: Redundant code can be removed.
1018
@item
1019
   Do not commit changes to the build system (Makefiles, configure script)
1020
   which change behavior, defaults etc, without asking first. The same
1021
   applies to compiler warning fixes, trivial looking fixes and to code
1022
   maintained by other developers. We usually have a reason for doing things
1023
   the way we do. Send your changes as patches to the ffmpeg-devel mailing
1024
   list, and if the code maintainers say OK, you may commit. This does not
1025
   apply to files you wrote and/or maintain.
1026
@item
1027
   We refuse source indentation and other cosmetic changes if they are mixed
1028
   with functional changes, such commits will be rejected and removed. Every
1029
   developer has his own indentation style, you should not change it. Of course
1030
   if you (re)write something, you can use your own style, even though we would
1031
   prefer if the indentation throughout FFmpeg was consistent (Many projects
1032
   force a given indentation style - we do not.). If you really need to make
1033
   indentation changes (try to avoid this), separate them strictly from real
1034
   changes.
1035

    
1036
   NOTE: If you had to put if()@{ .. @} over a large (> 5 lines) chunk of code,
1037
   then either do NOT change the indentation of the inner part within (do not
1038
   move it to the right)! or do so in a separate commit
1039
@item
1040
   Always fill out the commit log message. Describe in a few lines what you
1041
   changed and why. You can refer to mailing list postings if you fix a
1042
   particular bug. Comments such as "fixed!" or "Changed it." are unacceptable.
1043
@item
1044
   If you apply a patch by someone else, include the name and email address in
1045
   the log message. Since the ffmpeg-cvslog mailing list is publicly
1046
   archived you should add some SPAM protection to the email address. Send an
1047
   answer to ffmpeg-devel (or wherever you got the patch from) saying that
1048
   you applied the patch.
1049
@item
1050
   When applying patches that have been discussed (at length) on the mailing
1051
   list, reference the thread in the log message.
1052
@item
1053
    Do NOT commit to code actively maintained by others without permission.
1054
    Send a patch to ffmpeg-devel instead. If no one answers within a reasonable
1055
    timeframe (12h for build failures and security fixes, 3 days small changes,
1056
    1 week for big patches) then commit your patch if you think it is OK.
1057
    Also note, the maintainer can simply ask for more time to review!
1058
@item
1059
    Subscribe to the ffmpeg-cvslog mailing list. The diffs of all commits
1060
    are sent there and reviewed by all the other developers. Bugs and possible
1061
    improvements or general questions regarding commits are discussed there. We
1062
    expect you to react if problems with your code are uncovered.
1063
@item
1064
    Update the documentation if you change behavior or add features. If you are
1065
    unsure how best to do this, send a patch to ffmpeg-devel, the documentation
1066
    maintainer(s) will review and commit your stuff.
1067
@item
1068
    Try to keep important discussions and requests (also) on the public
1069
    developer mailing list, so that all developers can benefit from them.
1070
@item
1071
    Never write to unallocated memory, never write over the end of arrays,
1072
    always check values read from some untrusted source before using them
1073
    as array index or other risky things.
1074
@item
1075
    Remember to check if you need to bump versions for the specific libav
1076
    parts (libavutil, libavcodec, libavformat) you are changing. You need
1077
    to change the version integer.
1078
    Incrementing the first component means no backward compatibility to
1079
    previous versions (e.g. removal of a function from the public API).
1080
    Incrementing the second component means backward compatible change
1081
    (e.g. addition of a function to the public API or extension of an
1082
    existing data structure).
1083
    Incrementing the third component means a noteworthy binary compatible
1084
    change (e.g. encoder bug fix that matters for the decoder).
1085
@item
1086
    Compiler warnings indicate potential bugs or code with bad style. If a type of
1087
    warning always points to correct and clean code, that warning should
1088
    be disabled, not the code changed.
1089
    Thus the remaining warnings can either be bugs or correct code.
1090
    If it is a bug, the bug has to be fixed. If it is not, the code should
1091
    be changed to not generate a warning unless that causes a slowdown
1092
    or obfuscates the code.
1093
@item
1094
    If you add a new file, give it a proper license header. Do not copy and
1095
    paste it from a random place, use an existing file as template.
1096
@end enumerate
1097

    
1098
We think our rules are not too hard. If you have comments, contact us.
1099

    
1100
Note, these rules are mostly borrowed from the MPlayer project.
1101

    
1102
@section Submitting patches
1103

    
1104
First, (@pxref{Coding Rules}) above if you did not yet.
1105

    
1106
When you submit your patch, try to send a unified diff (diff '-up'
1107
option). We cannot read other diffs :-)
1108

    
1109
Also please do not submit a patch which contains several unrelated changes.
1110
Split it into separate, self-contained pieces. This does not mean splitting
1111
file by file. Instead, make the patch as small as possible while still
1112
keeping it as a logical unit that contains an individual change, even
1113
if it spans multiple files. This makes reviewing your patches much easier
1114
for us and greatly increases your chances of getting your patch applied.
1115

    
1116
Run the regression tests before submitting a patch so that you can
1117
verify that there are no big problems.
1118

    
1119
Patches should be posted as base64 encoded attachments (or any other
1120
encoding which ensures that the patch will not be trashed during
1121
transmission) to the ffmpeg-devel mailing list, see
1122
@url{http://lists.mplayerhq.hu/mailman/listinfo/ffmpeg-devel}
1123

    
1124
It also helps quite a bit if you tell us what the patch does (for example
1125
'replaces lrint by lrintf'), and why (for example '*BSD isn't C99 compliant
1126
and has no lrint()')
1127

    
1128
Also please if you send several patches, send each patch as a separate mail,
1129
do not attach several unrelated patches to the same mail.
1130

    
1131
@section New codecs or formats checklist
1132

    
1133
@enumerate
1134
@item
1135
    Did you use av_cold for codec initialization and close functions?
1136
@item
1137
    Did you add a long_name under NULL_IF_CONFIG_SMALL to the AVCodec or
1138
    AVInputFormat/AVOutputFormat struct?
1139
@item
1140
    Did you bump the minor version number in @file{avcodec.h} or
1141
    @file{avformat.h}?
1142
@item
1143
    Did you register it in @file{allcodecs.c} or @file{allformats.c}?
1144
@item
1145
    Did you add the CodecID to @file{avcodec.h}?
1146
@item
1147
    If it has a fourcc, did you add it to @file{libavformat/riff.c},
1148
    even if it is only a decoder?
1149
@item
1150
    Did you add a rule to compile the appropriate files in the Makefile?
1151
    Remember to do this even if you're just adding a format to a file that is
1152
    already being compiled by some other rule, like a raw demuxer.
1153
@item
1154
    Did you add an entry to the table of supported formats or codecs in the
1155
    documentation?
1156
@item
1157
    Did you add an entry in the Changelog?
1158
@item
1159
    If it depends on a parser or a library, did you add that dependency in
1160
    configure?
1161
@item
1162
    Did you "svn add" the appropriate files before commiting?
1163
@end enumerate
1164

    
1165
@section patch submission checklist
1166

    
1167
@enumerate
1168
@item
1169
    Do the regression tests pass with the patch applied?
1170
@item
1171
    Does @code{make checkheaders} pass with the patch applied?
1172
@item
1173
    Is the patch a unified diff?
1174
@item
1175
    Is the patch against latest FFmpeg SVN?
1176
@item
1177
    Are you subscribed to ffmpeg-dev?
1178
    (the list is subscribers only due to spam)
1179
@item
1180
    Have you checked that the changes are minimal, so that the same cannot be
1181
    achieved with a smaller patch and/or simpler final code?
1182
@item
1183
    If the change is to speed critical code, did you benchmark it?
1184
@item
1185
    If you did any benchmarks, did you provide them in the mail?
1186
@item
1187
    Have you checked that the patch does not introduce buffer overflows or
1188
    other security issues?
1189
@item
1190
    Did you test your decoder or demuxer against damaged data? If no, see
1191
    tools/trasher and the noise bitstream filter. Your decoder or demuxer
1192
    should not crash or end in a (near) infinite loop when fed damaged data.
1193
@item
1194
    Is the patch created from the root of the source tree, so it can be
1195
    applied with @code{patch -p0}?
1196
@item
1197
    Does the patch not mix functional and cosmetic changes?
1198
@item
1199
    Did you add tabs or trailing whitespace to the code? Both are forbidden.
1200
@item
1201
    Is the patch attached to the email you send?
1202
@item
1203
    Is the mime type of the patch correct? It should be text/x-diff or
1204
    text/x-patch or at least text/plain and not application/octet-stream.
1205
@item
1206
    If the patch fixes a bug, did you provide a verbose analysis of the bug?
1207
@item
1208
    If the patch fixes a bug, did you provide enough information, including
1209
    a sample, so the bug can be reproduced and the fix can be verified?
1210
    Note please do not attach samples >100k to mails but rather provide a
1211
    URL, you can upload to ftp://upload.ffmpeg.org
1212
@item
1213
    Did you provide a verbose summary about what the patch does change?
1214
@item
1215
    Did you provide a verbose explanation why it changes things like it does?
1216
@item
1217
    Did you provide a verbose summary of the user visible advantages and
1218
    disadvantages if the patch is applied?
1219
@item
1220
    Did you provide an example so we can verify the new feature added by the
1221
    patch easily?
1222
@item
1223
    If you added a new file, did you insert a license header? It should be
1224
    taken from FFmpeg, not randomly copied and pasted from somewhere else.
1225
@item
1226
    You should maintain alphabetical order in alphabetically ordered lists as
1227
    long as doing so does not break API/ABI compatibility.
1228
@item
1229
    Lines with similar content should be aligned vertically when doing so
1230
    improves readability.
1231
@item
1232
    Did you provide a suggestion for a clear commit log message?
1233
@end enumerate
1234

    
1235
@section Patch review process
1236

    
1237
All patches posted to ffmpeg-devel will be reviewed, unless they contain a
1238
clear note that the patch is not for SVN.
1239
Reviews and comments will be posted as replies to the patch on the
1240
mailing list. The patch submitter then has to take care of every comment,
1241
that can be by resubmitting a changed patch or by discussion. Resubmitted
1242
patches will themselves be reviewed like any other patch. If at some point
1243
a patch passes review with no comments then it is approved, that can for
1244
simple and small patches happen immediately while large patches will generally
1245
have to be changed and reviewed many times before they are approved.
1246
After a patch is approved it will be committed to the repository.
1247

    
1248
We will review all submitted patches, but sometimes we are quite busy so
1249
especially for large patches this can take several weeks.
1250

    
1251
When resubmitting patches, please do not make any significant changes
1252
not related to the comments received during review. Such patches will
1253
be rejected. Instead, submit  significant changes or new features as
1254
separate patches.
1255

    
1256
@section Regression tests
1257

    
1258
Before submitting a patch (or committing to the repository), you should at least
1259
test that you did not break anything.
1260

    
1261
The regression tests build a synthetic video stream and a synthetic
1262
audio stream. These are then encoded and decoded with all codecs or
1263
formats. The CRC (or MD5) of each generated file is recorded in a
1264
result file. A 'diff' is launched to compare the reference results and
1265
the result file.
1266

    
1267
The regression tests then go on to test the FFserver code with a
1268
limited set of streams. It is important that this step runs correctly
1269
as well.
1270

    
1271
Run 'make test' to test all the codecs and formats.
1272

    
1273
Run 'make fulltest' to test all the codecs, formats and FFserver.
1274

    
1275
[Of course, some patches may change the results of the regression tests. In
1276
this case, the reference results of the regression tests shall be modified
1277
accordingly].
1278

    
1279
@bye