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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 ADTS AAC audio            @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 ASF                       @tab X @tab X
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@item AVI                       @tab X @tab X
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@item AVM2 (Flash 9)            @tab X @tab X
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    @tab Only embedded audio is decoded.
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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 Bethsoft VID              @tab   @tab X
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    @tab Used in some games from Bethesda Softworks.
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@item BFI                       @tab   @tab X
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    @tab Brute Force & Ignorance, used in Flash Traffic: City of Angels.
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@item C93                       @tab   @tab X
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    @tab Used in the game Cyberia from Interplay.
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@item CIN                       @tab   @tab X
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    @tab Multimedia format used by Delphine Software games.
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@item Creative VOC              @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 DV                        @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 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 FLIC                      @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 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 MAXIS EA 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             @tab X @tab X
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@item MPEG audio                @tab X @tab X
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@item MPEG-1 systems            @tab X @tab X
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    @tab muxed audio and video
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@item MPEG-2 PS                 @tab X @tab X
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    @tab also known as @code{VOB} file
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@item MPEG-2 TS                 @tab   @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 MSN TCP webcam            @tab   @tab X
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    @tab Used by MSN Messenger webcam streams.
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@item MXF                       @tab X @tab X
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    @tab Material eXchange Format SMPTE 377M, used by D-Cinema, broadcast industry.
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@item Nullsoft Video            @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 OMA                       @tab   @tab X
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    @tab Audio format used in Sony Sonic Stage and Sony Vegas.
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@item PlayStation STR           @tab   @tab X
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@item PVA                       @tab   @tab X
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    @tab Used by TechnoTrend DVB PCI boards.
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@item raw AC-3                  @tab X @tab X
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@item raw CRI ADX audio         @tab X @tab X
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@item raw MJPEG                 @tab X @tab X
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@item raw MPEG video            @tab X @tab X
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@item raw MPEG-4 video          @tab X @tab X
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@item raw PCM 8/16/32 bits, 32/64-bit floating point, mu-law/A-law @tab X  @tab  X
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@item raw Shorten audio         @tab    @tab  X
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@item RealMedia                 @tab X @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 Sega FILM/CPK             @tab   @tab X
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    @tab Used in many Sega Saturn console games.
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@item 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 Sierra Online             @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 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 Smacker                   @tab   @tab X
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    @tab Multimedia format used by many games.
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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 WAV                       @tab X @tab X
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@item WC3 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 VQA/AUD  @tab   @tab X
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    @tab Multimedia formats used in Westwood Studios games.
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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 @tab one raw file per component
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@item animated GIF @tab X @tab X @tab Only uncompressed GIFs are generated.
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@item JPEG         @tab X @tab X @tab Progressive JPEG is not supported.
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@item PAM          @tab X @tab X @tab PAM is a PNM extension with alpha support.
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@item PCX          @tab   @tab X @tab PC Paintbrush
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@item PGM, PPM     @tab X @tab X
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@item PGMYUV       @tab X @tab X @tab PGM with U and V components in YUV 4:2:0
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@item PNG          @tab X @tab X @tab 2/4 bpp not supported yet
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@item PTX          @tab   @tab X @tab V.Flash PTX format
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@item RAS          @tab   @tab X @tab Sun Rasterfile
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@item SGI          @tab X @tab X @tab SGI RGB image format
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@item Targa        @tab   @tab X @tab Targa (.TGA) image format
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@item TIFF         @tab X @tab X @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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@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 Video  @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 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 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 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
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@item Duck DK3 IMA ADPCM     @tab     @tab  X
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    @tab Used in some Sega Saturn console games.
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@item Duck DK4 IMA ADPCM     @tab     @tab  X
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    @tab Used in some Sega Saturn console games.
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@item DV audio               @tab     @tab  X
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@item Electronic Arts ADPCM  @tab     @tab  X
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    @tab Used in various EA titles.
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@item Enhanced AC-3          @tab     @tab  X
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@item FLAC lossless audio    @tab IX  @tab  X
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@item G.726  ADPCM           @tab  X  @tab  X
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@item GSM                    @tab  E  @tab  E
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    @tab supported through external library libgsm
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@item GSM_MS                 @tab  E  @tab  E
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    @tab supported through external library libgsm
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@item id RoQ DPCM            @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 Music Coder      @tab     @tab  X
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@item Interplay MVE DPCM     @tab     @tab  X
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    @tab Used in various Interplay computer games.
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@item MAXIS EA ADPCM         @tab     @tab  X
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    @tab Used in Sim City 3000.
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@item Microsoft ADPCM        @tab  X  @tab  X
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@item MLP/TrueHD             @tab     @tab  X
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    @tab Used in DVD-Audio and Blu-Ray discs.
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@item Monkey's Audio         @tab     @tab  X
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    @tab Only versions 3.97-3.99 are supported.
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@item MPEG audio layer 3     @tab  E  @tab IX
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    @tab encoding supported through external library LAME
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@item MPEG audio layer 2     @tab IX  @tab IX
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@item MS IMA ADPCM           @tab  X  @tab  X
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@item Musepack               @tab     @tab  X
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    @tab SV7 and SV8 are supported.
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@item Nellymoser ASAO        @tab  X  @tab  X
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@item QCELP / PureVoice      @tab     @tab  X
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@item Qdesign QDM2           @tab     @tab  X
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    @tab There are still some distortions.
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@item QT IMA ADPCM           @tab  X  @tab  X
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@item RA144                  @tab     @tab  X
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    @tab Real 14400 bit/s codec
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@item RA288                  @tab     @tab  X
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    @tab Real 28800 bit/s codec
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@item RADnet                 @tab IX  @tab IX
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    @tab Real low bitrate AC-3 codec
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@item Real COOK              @tab     @tab  X
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    @tab All versions except 5.1 are supported.
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@item Shorten                @tab     @tab  X
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@item Sierra Online DPCM     @tab     @tab  X
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    @tab Used in Sierra Online game audio files.
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@item Smacker audio          @tab     @tab  X
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@item SMJPEG IMA ADPCM       @tab     @tab  X
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    @tab Used in certain Loki game ports.
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@item Sonic                  @tab  X  @tab  X
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    @tab experimental codec
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@item Sonic lossless         @tab  X  @tab  X
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    @tab experimental codec
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@item Speex                  @tab     @tab  E
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    @tab supported through external library libspeex
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@item THP ADPCM              @tab     @tab  X
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    @tab Used on the Nintendo GameCube.
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@item True Audio (TTA)       @tab     @tab  X
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@item Vorbis                 @tab  X  @tab  X
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@item WavPack                @tab     @tab  X
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@item Westwood Studios IMA ADPCM @tab     @tab  X
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    @tab Used in Westwood Studios games like Command and Conquer.
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@item WMA v1/v2              @tab  X  @tab  X
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@item Xan DPCM               @tab     @tab  X
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    @tab Used in Origin's Wing Commander IV AVI files.
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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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@code{I} means that an integer-only version is available, too (ensures high
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performance on systems without hardware floating point support).
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@section Subtitle Formats
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@multitable @columnfractions .4 .1 .1 .1 .1 .1
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@item Name @tab Muxing @tab Demuxing @tab Encoding @tab Decoding @tab Rendering
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@item ASS/SSA      @tab X @tab X
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@item DVB          @tab X @tab X @tab X @tab X @tab X
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@item DVD          @tab X @tab X @tab X @tab X @tab X
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@end multitable
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@code{X} means that the feature is supported.
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@chapter Platform Specific information
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@section BSD
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BSD make will not build FFmpeg, you need to install and use GNU Make
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(@file{gmake}).
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@section Windows
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To get help and instructions for building FFmpeg under Windows, check out
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the FFmpeg Windows Help Forum at
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@url{http://ffmpeg.arrozcru.org/}.
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@subsection Native Windows compilation
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FFmpeg can be built to run natively on Windows using the MinGW tools. Install
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the latest versions of MSYS and MinGW from @url{http://www.mingw.org/}.
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You can find detailed installation
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instructions in the download section and the FAQ.
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FFmpeg does not build out-of-the-box with the packages the automated MinGW
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installer provides. It also requires coreutils to be installed and many other
476
packages updated to the latest version. The minimum version for some packages
477
are listed below:
478

    
479
@itemize
480
@item bash 3.1
481
@item msys-make 3.81-2 (note: not mingw32-make)
482
@item w32api 3.13
483
@item mingw-runtime 3.15
484
@end itemize
485

    
486
You will also need to pass @code{-fno-common} to the compiler to work around
487
a GCC bug (see @url{http://gcc.gnu.org/bugzilla/show_bug.cgi?id=37216}).
488

    
489
Within the MSYS shell, configure and make with:
490

    
491
@example
492
./configure --enable-memalign-hack --extra-cflags=-fno-common
493
make
494
make install
495
@end example
496

    
497
This will install @file{ffmpeg.exe} along with many other development files
498
to @file{/usr/local}. You may specify another install path using the
499
@code{--prefix} option in @file{configure}.
500

    
501
Notes:
502

    
503
@itemize
504

    
505
@item In order to compile vhooks, you must have a POSIX-compliant libdl in
506
your MinGW system. Get dlfcn-win32 from
507
@url{http://code.google.com/p/dlfcn-win32}.
508

    
509
@item In order to compile FFplay, you must have the MinGW development library
510
of SDL. Get it from @url{http://www.libsdl.org}.
511
Edit the @file{bin/sdl-config} script so that it points to the correct prefix
512
where SDL was installed. Verify that @file{sdl-config} can be launched from
513
the MSYS command line.
514

    
515
@item By using @code{./configure --enable-shared} when configuring FFmpeg,
516
you can build libavutil, libavcodec and libavformat as DLLs.
517

    
518
@end itemize
519

    
520
@subsection Microsoft Visual C++ compatibility
521

    
522
As stated in the FAQ, FFmpeg will not compile under MSVC++. However, if you
523
want to use the libav* libraries in your own applications, you can still
524
compile those applications using MSVC++. But the libav* libraries you link
525
to @emph{must} be built with MinGW. However, you will not be able to debug
526
inside the libav* libraries, since MSVC++ does not recognize the debug
527
symbols generated by GCC.
528
We strongly recommend you to move over from MSVC++ to MinGW tools.
529

    
530
This description of how to use the FFmpeg libraries with MSVC++ is based on
531
Microsoft Visual C++ 2005 Express Edition. If you have a different version,
532
you might have to modify the procedures slightly.
533

    
534
@subsubsection Using static libraries
535

    
536
Assuming you have just built and installed FFmpeg in @file{/usr/local}.
537

    
538
@enumerate
539

    
540
@item Create a new console application ("File / New / Project") and then
541
select "Win32 Console Application". On the appropriate page of the
542
Application Wizard, uncheck the "Precompiled headers" option.
543

    
544
@item Write the source code for your application, or, for testing, just
545
copy the code from an existing sample application into the source file
546
that MSVC++ has already created for you. For example, you can copy
547
@file{output_example.c} from the FFmpeg distribution.
548

    
549
@item Open the "Project / Properties" dialog box. In the "Configuration"
550
combo box, select "All Configurations" so that the changes you make will
551
affect both debug and release builds. In the tree view on the left hand
552
side, select "C/C++ / General", then edit the "Additional Include
553
Directories" setting to contain the path where the FFmpeg includes were
554
installed (i.e. @file{c:\msys\1.0\local\include}).
555
Do not add MinGW's include directory here, or the include files will
556
conflict with MSVC's.
557

    
558
@item Still in the "Project / Properties" dialog box, select
559
"Linker / General" from the tree view and edit the
560
"Additional Library Directories" setting to contain the @file{lib}
561
directory where FFmpeg was installed (i.e. @file{c:\msys\1.0\local\lib}),
562
the directory where MinGW libs are installed (i.e. @file{c:\mingw\lib}),
563
and the directory where MinGW's GCC libs are installed
564
(i.e. @file{C:\mingw\lib\gcc\mingw32\4.2.1-sjlj}). Then select
565
"Linker / Input" from the tree view, and add the files @file{libavformat.a},
566
@file{libavcodec.a}, @file{libavutil.a}, @file{libmingwex.a},
567
@file{libgcc.a}, and any other libraries you used (i.e. @file{libz.a})
568
to the end of "Additional Dependencies".
569

    
570
@item Now, select "C/C++ / Code Generation" from the tree view. Select
571
"Debug" in the "Configuration" combo box. Make sure that "Runtime
572
Library" is set to "Multi-threaded Debug DLL". Then, select "Release" in
573
the "Configuration" combo box and make sure that "Runtime Library" is
574
set to "Multi-threaded DLL".
575

    
576
@item Click "OK" to close the "Project / Properties" dialog box.
577

    
578
@item MSVC++ lacks some C99 header files that are fundamental for FFmpeg.
579
Get msinttypes from @url{http://code.google.com/p/msinttypes/downloads/list}
580
and install it in MSVC++'s include directory
581
(i.e. @file{C:\Program Files\Microsoft Visual Studio 8\VC\include}).
582

    
583
@item MSVC++ also does not understand the @code{inline} keyword used by
584
FFmpeg, so you must add this line before @code{#include}ing libav*:
585
@example
586
#define inline _inline
587
@end example
588

    
589
@item Build your application, everything should work.
590

    
591
@end enumerate
592

    
593
@subsubsection Using shared libraries
594

    
595
This is how to create DLL and LIB files that are compatible with MSVC++:
596

    
597
@enumerate
598

    
599
@item Add a call to @file{vcvars32.bat} (which sets up the environment
600
variables for the Visual C++ tools) as the first line of @file{msys.bat}.
601
The standard location for @file{vcvars32.bat} is
602
@file{C:\Program Files\Microsoft Visual Studio 8\VC\bin\vcvars32.bat},
603
and the standard location for @file{msys.bat} is @file{C:\msys\1.0\msys.bat}.
604
If this corresponds to your setup, add the following line as the first line
605
of @file{msys.bat}:
606

    
607
@example
608
call "C:\Program Files\Microsoft Visual Studio 8\VC\bin\vcvars32.bat"
609
@end example
610

    
611
Alternatively, you may start the @file{Visual Studio 2005 Command Prompt},
612
and run @file{c:\msys\1.0\msys.bat} from there.
613

    
614
@item Within the MSYS shell, run @code{lib.exe}. If you get a help message
615
from @file{Microsoft (R) Library Manager}, this means your environment
616
variables are set up correctly, the @file{Microsoft (R) Library Manager}
617
is on the path and will be used by FFmpeg to create
618
MSVC++-compatible import libraries.
619

    
620
@item Build FFmpeg with
621

    
622
@example
623
./configure --enable-shared --enable-memalign-hack
624
make
625
make install
626
@end example
627

    
628
Your install path (@file{/usr/local/} by default) should now have the
629
necessary DLL and LIB files under the @file{bin} directory.
630

    
631
@end enumerate
632

    
633
To use those files with MSVC++, do the same as you would do with
634
the static libraries, as described above. But in Step 4,
635
you should only need to add the directory where the LIB files are installed
636
(i.e. @file{c:\msys\usr\local\bin}). This is not a typo, the LIB files are
637
installed in the @file{bin} directory. And instead of adding @file{libxx.a}
638
files, you should add @file{avcodec.lib}, @file{avformat.lib}, and
639
@file{avutil.lib}. There should be no need for @file{libmingwex.a},
640
@file{libgcc.a}, and @file{wsock32.lib}, nor any other external library
641
statically linked into the DLLs. The @file{bin} directory contains a bunch
642
of DLL files, but the ones that are actually used to run your application
643
are the ones with a major version number in their filenames
644
(i.e. @file{avcodec-51.dll}).
645

    
646
@subsection Cross compilation for Windows with Linux
647

    
648
You must use the MinGW cross compilation tools available at
649
@url{http://www.mingw.org/}.
650

    
651
Then configure FFmpeg with the following options:
652
@example
653
./configure --target-os=mingw32 --cross-prefix=i386-mingw32msvc-
654
@end example
655
(you can change the cross-prefix according to the prefix chosen for the
656
MinGW tools).
657

    
658
Then you can easily test FFmpeg with Wine
659
(@url{http://www.winehq.com/}).
660

    
661
@subsection Compilation under Cygwin
662

    
663
The main issue with Cygwin is that newlib, its C library, does not
664
contain llrint().  However, it is possible to leverage the
665
implementation in MinGW.
666

    
667
Just install your Cygwin with all the "Base" packages, plus the
668
following "Devel" ones:
669
@example
670
binutils, gcc-core, make, subversion, mingw-runtime
671
@end example
672

    
673
Do not install binutils-20060709-1 (they are buggy on shared builds);
674
use binutils-20050610-1 instead.
675

    
676
Then create a small library that just contains llrint():
677

    
678
@example
679
ar x /usr/lib/mingw/libmingwex.a llrint.o
680
ar cq /usr/local/lib/libllrint.a llrint.o
681
@end example
682

    
683
Then run
684

    
685
@example
686
./configure --enable-static --disable-shared  --extra-ldflags='-L /usr/local/lib' --extra-libs='-l llrint'
687
@end example
688

    
689
to make a static build or
690

    
691
@example
692
./configure --enable-shared --disable-static  --extra-ldflags='-L /usr/local/lib' --extra-libs='-l llrint'
693
@end example
694

    
695
to build shared libraries.
696

    
697
If you want to build FFmpeg with additional libraries, download Cygwin
698
"Devel" packages for Ogg and Vorbis from any Cygwin packages repository
699
and/or SDL, xvid, faac, faad2 packages from Cygwin Ports,
700
(@url{http://cygwinports.dotsrc.org/}).
701

    
702
@subsection Crosscompilation for Windows under Cygwin
703

    
704
With Cygwin you can create Windows binaries that do not need the cygwin1.dll.
705

    
706
Just install your Cygwin as explained before, plus these additional
707
"Devel" packages:
708
@example
709
gcc-mingw-core, mingw-runtime, mingw-zlib
710
@end example
711

    
712
and add some special flags to your configure invocation.
713

    
714
For a static build run
715
@example
716
./configure --target-os=mingw32 --enable-memalign-hack --enable-static --disable-shared --extra-cflags=-mno-cygwin --extra-libs=-mno-cygwin
717
@end example
718

    
719
and for a build with shared libraries
720
@example
721
./configure --target-os=mingw32 --enable-memalign-hack --enable-shared --disable-static --extra-cflags=-mno-cygwin --extra-libs=-mno-cygwin
722
@end example
723

    
724
@section BeOS
725

    
726
BeOS support is broken in mysterious ways.
727

    
728
@section OS/2
729

    
730
For information about compiling FFmpeg on OS/2 see
731
@url{http://www.edm2.com/index.php/FFmpeg}.
732

    
733
@chapter Developers Guide
734

    
735
@section API
736
@itemize @bullet
737
@item libavcodec is the library containing the codecs (both encoding and
738
decoding). Look at @file{libavcodec/apiexample.c} to see how to use it.
739

    
740
@item libavformat is the library containing the file format handling (mux and
741
demux code for several formats). Look at @file{ffplay.c} to use it in a
742
player. See @file{output_example.c} to use it to generate audio or video
743
streams.
744

    
745
@end itemize
746

    
747
@section Integrating libavcodec or libavformat in your program
748

    
749
You can integrate all the source code of the libraries to link them
750
statically to avoid any version problem. All you need is to provide a
751
'config.mak' and a 'config.h' in the parent directory. See the defines
752
generated by ./configure to understand what is needed.
753

    
754
You can use libavcodec or libavformat in your commercial program, but
755
@emph{any patch you make must be published}. The best way to proceed is
756
to send your patches to the FFmpeg mailing list.
757

    
758
@node Coding Rules
759
@section Coding Rules
760

    
761
FFmpeg is programmed in the ISO C90 language with a few additional
762
features from ISO C99, namely:
763
@itemize @bullet
764
@item
765
the @samp{inline} keyword;
766
@item
767
@samp{//} comments;
768
@item
769
designated struct initializers (@samp{struct s x = @{ .i = 17 @};})
770
@item
771
compound literals (@samp{x = (struct s) @{ 17, 23 @};})
772
@end itemize
773

    
774
These features are supported by all compilers we care about, so we will not
775
accept patches to remove their use unless they absolutely do not impair
776
clarity and performance.
777

    
778
All code must compile with GCC 2.95 and GCC 3.3. Currently, FFmpeg also
779
compiles with several other compilers, such as the Compaq ccc compiler
780
or Sun Studio 9, and we would like to keep it that way unless it would
781
be exceedingly involved. To ensure compatibility, please do not use any
782
additional C99 features or GCC extensions. Especially watch out for:
783
@itemize @bullet
784
@item
785
mixing statements and declarations;
786
@item
787
@samp{long long} (use @samp{int64_t} instead);
788
@item
789
@samp{__attribute__} not protected by @samp{#ifdef __GNUC__} or similar;
790
@item
791
GCC statement expressions (@samp{(x = (@{ int y = 4; y; @})}).
792
@end itemize
793

    
794
Indent size is 4.
795
The presentation is the one specified by 'indent -i4 -kr -nut'.
796
The TAB character is forbidden outside of Makefiles as is any
797
form of trailing whitespace. Commits containing either will be
798
rejected by the Subversion repository.
799

    
800
The main priority in FFmpeg is simplicity and small code size in order to
801
minimize the bug count.
802

    
803
Comments: Use the JavaDoc/Doxygen
804
format (see examples below) so that code documentation
805
can be generated automatically. All nontrivial functions should have a comment
806
above them explaining what the function does, even if it is just one sentence.
807
All structures and their member variables should be documented, too.
808
@example
809
/**
810
 * @@file mpeg.c
811
 * MPEG codec.
812
 * @@author ...
813
 */
814

    
815
/**
816
 * Summary sentence.
817
 * more text ...
818
 * ...
819
 */
820
typedef struct Foobar@{
821
    int var1; /**< var1 description */
822
    int var2; ///< var2 description
823
    /** var3 description */
824
    int var3;
825
@} Foobar;
826

    
827
/**
828
 * Summary sentence.
829
 * more text ...
830
 * ...
831
 * @@param my_parameter description of my_parameter
832
 * @@return return value description
833
 */
834
int myfunc(int my_parameter)
835
...
836
@end example
837

    
838
fprintf and printf are forbidden in libavformat and libavcodec,
839
please use av_log() instead.
840

    
841
Casts should be used only when necessary. Unneeded parentheses
842
should also be avoided if they don't make the code easier to understand.
843

    
844
@section Development Policy
845

    
846
@enumerate
847
@item
848
   Contributions should be licensed under the LGPL 2.1, including an
849
   "or any later version" clause, or the MIT license.  GPL 2 including
850
   an "or any later version" clause is also acceptable, but LGPL is
851
   preferred.
852
@item
853
   You must not commit code which breaks FFmpeg! (Meaning unfinished but
854
   enabled code which breaks compilation or compiles but does not work or
855
   breaks the regression tests)
856
   You can commit unfinished stuff (for testing etc), but it must be disabled
857
   (#ifdef etc) by default so it does not interfere with other developers'
858
   work.
859
@item
860
   You do not have to over-test things. If it works for you, and you think it
861
   should work for others, then commit. If your code has problems
862
   (portability, triggers compiler bugs, unusual environment etc) they will be
863
   reported and eventually fixed.
864
@item
865
   Do not commit unrelated changes together, split them into self-contained
866
   pieces. Also do not forget that if part B depends on part A, but A does not
867
   depend on B, then A can and should be committed first and separate from B.
868
   Keeping changes well split into self-contained parts makes reviewing and
869
   understanding them on the commit log mailing list easier. This also helps
870
   in case of debugging later on.
871
   Also if you have doubts about splitting or not splitting, do not hesitate to
872
   ask/discuss it on the developer mailing list.
873
@item
874
   Do not change behavior of the program (renaming options etc) without
875
   first discussing it on the ffmpeg-devel mailing list. Do not remove
876
   functionality from the code. Just improve!
877

    
878
   Note: Redundant code can be removed.
879
@item
880
   Do not commit changes to the build system (Makefiles, configure script)
881
   which change behavior, defaults etc, without asking first. The same
882
   applies to compiler warning fixes, trivial looking fixes and to code
883
   maintained by other developers. We usually have a reason for doing things
884
   the way we do. Send your changes as patches to the ffmpeg-devel mailing
885
   list, and if the code maintainers say OK, you may commit. This does not
886
   apply to files you wrote and/or maintain.
887
@item
888
   We refuse source indentation and other cosmetic changes if they are mixed
889
   with functional changes, such commits will be rejected and removed. Every
890
   developer has his own indentation style, you should not change it. Of course
891
   if you (re)write something, you can use your own style, even though we would
892
   prefer if the indentation throughout FFmpeg was consistent (Many projects
893
   force a given indentation style - we do not.). If you really need to make
894
   indentation changes (try to avoid this), separate them strictly from real
895
   changes.
896

    
897
   NOTE: If you had to put if()@{ .. @} over a large (> 5 lines) chunk of code,
898
   then either do NOT change the indentation of the inner part within (do not
899
   move it to the right)! or do so in a separate commit
900
@item
901
   Always fill out the commit log message. Describe in a few lines what you
902
   changed and why. You can refer to mailing list postings if you fix a
903
   particular bug. Comments such as "fixed!" or "Changed it." are unacceptable.
904
@item
905
   If you apply a patch by someone else, include the name and email address in
906
   the log message. Since the ffmpeg-cvslog mailing list is publicly
907
   archived you should add some SPAM protection to the email address. Send an
908
   answer to ffmpeg-devel (or wherever you got the patch from) saying that
909
   you applied the patch.
910
@item
911
   When applying patches that have been discussed (at length) on the mailing
912
   list, reference the thread in the log message.
913
@item
914
    Do NOT commit to code actively maintained by others without permission.
915
    Send a patch to ffmpeg-devel instead. If no one answers within a reasonable
916
    timeframe (12h for build failures and security fixes, 3 days small changes,
917
    1 week for big patches) then commit your patch if you think it is OK.
918
    Also note, the maintainer can simply ask for more time to review!
919
@item
920
    Subscribe to the ffmpeg-cvslog mailing list. The diffs of all commits
921
    are sent there and reviewed by all the other developers. Bugs and possible
922
    improvements or general questions regarding commits are discussed there. We
923
    expect you to react if problems with your code are uncovered.
924
@item
925
    Update the documentation if you change behavior or add features. If you are
926
    unsure how best to do this, send a patch to ffmpeg-devel, the documentation
927
    maintainer(s) will review and commit your stuff.
928
@item
929
    Try to keep important discussions and requests (also) on the public
930
    developer mailing list, so that all developers can benefit from them.
931
@item
932
    Never write to unallocated memory, never write over the end of arrays,
933
    always check values read from some untrusted source before using them
934
    as array index or other risky things.
935
@item
936
    Remember to check if you need to bump versions for the specific libav
937
    parts (libavutil, libavcodec, libavformat) you are changing. You need
938
    to change the version integer.
939
    Incrementing the first component means no backward compatibility to
940
    previous versions (e.g. removal of a function from the public API).
941
    Incrementing the second component means backward compatible change
942
    (e.g. addition of a function to the public API or extension of an
943
    existing data structure).
944
    Incrementing the third component means a noteworthy binary compatible
945
    change (e.g. encoder bug fix that matters for the decoder).
946
@item
947
    Compiler warnings indicate potential bugs or code with bad style. If a type of
948
    warning always points to correct and clean code, that warning should
949
    be disabled, not the code changed.
950
    Thus the remaining warnings can either be bugs or correct code.
951
    If it is a bug, the bug has to be fixed. If it is not, the code should
952
    be changed to not generate a warning unless that causes a slowdown
953
    or obfuscates the code.
954
@item
955
    If you add a new file, give it a proper license header. Do not copy and
956
    paste it from a random place, use an existing file as template.
957
@end enumerate
958

    
959
We think our rules are not too hard. If you have comments, contact us.
960

    
961
Note, these rules are mostly borrowed from the MPlayer project.
962

    
963
@section Submitting patches
964

    
965
First, (@pxref{Coding Rules}) above if you did not yet.
966

    
967
When you submit your patch, try to send a unified diff (diff '-up'
968
option). We cannot read other diffs :-)
969

    
970
Also please do not submit a patch which contains several unrelated changes.
971
Split it into separate, self-contained pieces. This does not mean splitting
972
file by file. Instead, make the patch as small as possible while still
973
keeping it as a logical unit that contains an individual change, even
974
if it spans multiple files. This makes reviewing your patches much easier
975
for us and greatly increases your chances of getting your patch applied.
976

    
977
Run the regression tests before submitting a patch so that you can
978
verify that there are no big problems.
979

    
980
Patches should be posted as base64 encoded attachments (or any other
981
encoding which ensures that the patch will not be trashed during
982
transmission) to the ffmpeg-devel mailing list, see
983
@url{http://lists.mplayerhq.hu/mailman/listinfo/ffmpeg-devel}
984

    
985
It also helps quite a bit if you tell us what the patch does (for example
986
'replaces lrint by lrintf'), and why (for example '*BSD isn't C99 compliant
987
and has no lrint()')
988

    
989
Also please if you send several patches, send each patch as a separate mail,
990
do not attach several unrelated patches to the same mail.
991

    
992
@section New codecs or formats checklist
993

    
994
@enumerate
995
@item
996
    Did you use av_cold for codec initialization and close functions?
997
@item
998
    Did you add a long_name under NULL_IF_CONFIG_SMALL to the AVCodec or
999
    AVInputFormat/AVOutputFormat struct?
1000
@item
1001
    Did you bump the minor version number in @file{avcodec.h} or
1002
    @file{avformat.h}?
1003
@item
1004
    Did you register it in @file{allcodecs.c} or @file{allformats.c}?
1005
@item
1006
    Did you add the CodecID to @file{avcodec.h}?
1007
@item
1008
    If it has a fourcc, did you add it to @file{libavformat/riff.c},
1009
    even if it is only a decoder?
1010
@item
1011
    Did you add a rule to compile the appropriate files in the Makefile?
1012
    Remember to do this even if you're just adding a format to a file that is
1013
    already being compiled by some other rule, like a raw demuxer.
1014
@item
1015
    Did you add an entry to the table of supported formats or codecs in the
1016
    documentation?
1017
@item
1018
    Did you add an entry in the Changelog?
1019
@item
1020
    If it depends on a parser or a library, did you add that dependency in
1021
    configure?
1022
@item
1023
    Did you "svn add" the appropriate files before commiting?
1024
@end enumerate
1025

    
1026
@section patch submission checklist
1027

    
1028
@enumerate
1029
@item
1030
    Do the regression tests pass with the patch applied?
1031
@item
1032
    Does @code{make checkheaders} pass with the patch applied?
1033
@item
1034
    Is the patch a unified diff?
1035
@item
1036
    Is the patch against latest FFmpeg SVN?
1037
@item
1038
    Are you subscribed to ffmpeg-dev?
1039
    (the list is subscribers only due to spam)
1040
@item
1041
    Have you checked that the changes are minimal, so that the same cannot be
1042
    achieved with a smaller patch and/or simpler final code?
1043
@item
1044
    If the change is to speed critical code, did you benchmark it?
1045
@item
1046
    If you did any benchmarks, did you provide them in the mail?
1047
@item
1048
    Have you checked that the patch does not introduce buffer overflows or
1049
    other security issues?
1050
@item
1051
    Did you test your decoder or demuxer against damaged data? If no, see
1052
    tools/trasher and the noise bitstream filter. Your decoder or demuxer
1053
    should not crash or end in a (near) infinite loop when fed damaged data.
1054
@item
1055
    Is the patch created from the root of the source tree, so it can be
1056
    applied with @code{patch -p0}?
1057
@item
1058
    Does the patch not mix functional and cosmetic changes?
1059
@item
1060
    Did you add tabs or trailing whitespace to the code? Both are forbidden.
1061
@item
1062
    Is the patch attached to the email you send?
1063
@item
1064
    Is the mime type of the patch correct? It should be text/x-diff or
1065
    text/x-patch or at least text/plain and not application/octet-stream.
1066
@item
1067
    If the patch fixes a bug, did you provide a verbose analysis of the bug?
1068
@item
1069
    If the patch fixes a bug, did you provide enough information, including
1070
    a sample, so the bug can be reproduced and the fix can be verified?
1071
    Note please do not attach samples >100k to mails but rather provide a
1072
    URL, you can upload to ftp://upload.mplayerhq.hu
1073
@item
1074
    Did you provide a verbose summary about what the patch does change?
1075
@item
1076
    Did you provide a verbose explanation why it changes things like it does?
1077
@item
1078
    Did you provide a verbose summary of the user visible advantages and
1079
    disadvantages if the patch is applied?
1080
@item
1081
    Did you provide an example so we can verify the new feature added by the
1082
    patch easily?
1083
@item
1084
    If you added a new file, did you insert a license header? It should be
1085
    taken from FFmpeg, not randomly copied and pasted from somewhere else.
1086
@item
1087
    You should maintain alphabetical order in alphabetically ordered lists as
1088
    long as doing so does not break API/ABI compatibility.
1089
@item
1090
    Lines with similar content should be aligned vertically when doing so
1091
    improves readability.
1092
@item
1093
    Did you provide a suggestion for a clear commit log message?
1094
@end enumerate
1095

    
1096
@section Patch review process
1097

    
1098
All patches posted to ffmpeg-devel will be reviewed, unless they contain a
1099
clear note that the patch is not for SVN.
1100
Reviews and comments will be posted as replies to the patch on the
1101
mailing list. The patch submitter then has to take care of every comment,
1102
that can be by resubmitting a changed patch or by discussion. Resubmitted
1103
patches will themselves be reviewed like any other patch. If at some point
1104
a patch passes review with no comments then it is approved, that can for
1105
simple and small patches happen immediately while large patches will generally
1106
have to be changed and reviewed many times before they are approved.
1107
After a patch is approved it will be committed to the repository.
1108

    
1109
We will review all submitted patches, but sometimes we are quite busy so
1110
especially for large patches this can take several weeks.
1111

    
1112
When resubmitting patches, please do not make any significant changes
1113
not related to the comments received during review. Such patches will
1114
be rejected. Instead, submit  significant changes or new features as
1115
separate patches.
1116

    
1117
@section Regression tests
1118

    
1119
Before submitting a patch (or committing to the repository), you should at least
1120
test that you did not break anything.
1121

    
1122
The regression tests build a synthetic video stream and a synthetic
1123
audio stream. These are then encoded and decoded with all codecs or
1124
formats. The CRC (or MD5) of each generated file is recorded in a
1125
result file. A 'diff' is launched to compare the reference results and
1126
the result file.
1127

    
1128
The regression tests then go on to test the FFserver code with a
1129
limited set of streams. It is important that this step runs correctly
1130
as well.
1131

    
1132
Run 'make test' to test all the codecs and formats.
1133

    
1134
Run 'make fulltest' to test all the codecs, formats and FFserver.
1135

    
1136
[Of course, some patches may change the results of the regression tests. In
1137
this case, the reference results of the regression tests shall be modified
1138
accordingly].
1139

    
1140
@bye