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\input texinfo @c -*- texinfo -*-
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@settitle FFmpeg Documentation
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@titlepage
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@sp 7
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@center @titlefont{FFmpeg Documentation}
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@sp 3
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@end titlepage
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@chapter Introduction
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FFmpeg is a very fast video and audio converter. It can also grab from
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a live audio/video source.
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The command line interface is designed to be intuitive, in the sense
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that FFmpeg tries to figure out all parameters that can possibly be
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derived automatically. You usually only have to specify the target
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bitrate you want.
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FFmpeg can also convert from any sample rate to any other, and resize
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video on the fly with a high quality polyphase filter.
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@chapter Quick Start
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@c man begin EXAMPLES
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@section Video and Audio grabbing
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FFmpeg can grab video and audio from devices given that you specify the input
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format and device.
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@example
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ffmpeg -f audio_device -i /dev/dsp -f video4linux2 -i /dev/video0 /tmp/out.mpg
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@end example
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Note that you must activate the right video source and channel before
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launching FFmpeg with any TV viewer such as xawtv
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(@url{http://bytesex.org/xawtv/}) by Gerd Knorr. You also
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have to set the audio recording levels correctly with a
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standard mixer.
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@section X11 grabbing
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FFmpeg can grab the X11 display.
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@example
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ffmpeg -f x11grab -i :0.0 /tmp/out.mpg
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@end example
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0.0 is display.screen number of your X11 server, same as
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the DISPLAY environment variable.
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@example
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ffmpeg -f x11grab -i :0.0+10,20 /tmp/out.mpg
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@end example
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0.0 is display.screen number of your X11 server, same as the DISPLAY environment
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variable. 10 is the x-offset and 20 the y-offset for the grabbing.
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@section Video and Audio file format conversion
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* FFmpeg can use any supported file format and protocol as input:
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Examples:
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* You can use YUV files as input:
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@example
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ffmpeg -i /tmp/test%d.Y /tmp/out.mpg
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@end example
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It will use the files:
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@example
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/tmp/test0.Y, /tmp/test0.U, /tmp/test0.V,
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/tmp/test1.Y, /tmp/test1.U, /tmp/test1.V, etc...
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@end example
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The Y files use twice the resolution of the U and V files. They are
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raw files, without header. They can be generated by all decent video
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decoders. You must specify the size of the image with the @option{-s} option
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if FFmpeg cannot guess it.
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* You can input from a raw YUV420P file:
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@example
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ffmpeg -i /tmp/test.yuv /tmp/out.avi
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@end example
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test.yuv is a file containing raw YUV planar data. Each frame is composed
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of the Y plane followed by the U and V planes at half vertical and
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horizontal resolution.
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* You can output to a raw YUV420P file:
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@example
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ffmpeg -i mydivx.avi hugefile.yuv
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@end example
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* You can set several input files and output files:
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@example
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ffmpeg -i /tmp/a.wav -s 640x480 -i /tmp/a.yuv /tmp/a.mpg
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@end example
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Converts the audio file a.wav and the raw YUV video file a.yuv
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to MPEG file a.mpg.
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* You can also do audio and video conversions at the same time:
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@example
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ffmpeg -i /tmp/a.wav -ar 22050 /tmp/a.mp2
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@end example
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Converts a.wav to MPEG audio at 22050Hz sample rate.
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* You can encode to several formats at the same time and define a
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mapping from input stream to output streams:
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@example
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ffmpeg -i /tmp/a.wav -ab 64k /tmp/a.mp2 -ab 128k /tmp/b.mp2 -map 0:0 -map 0:0
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@end example
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Converts a.wav to a.mp2 at 64 kbits and to b.mp2 at 128 kbits. '-map
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file:index' specifies which input stream is used for each output
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stream, in the order of the definition of output streams.
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* You can transcode decrypted VOBs
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@example
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ffmpeg -i snatch_1.vob -f avi -vcodec mpeg4 -b 800k -g 300 -bf 2 -acodec mp3 -ab 128k snatch.avi
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@end example
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This is a typical DVD ripping example; the input is a VOB file, the
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output an AVI file with MPEG-4 video and MP3 audio. Note that in this
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command we use B-frames so the MPEG-4 stream is DivX5 compatible, and
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GOP size is 300 which means one intra frame every 10 seconds for 29.97fps
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input video. Furthermore, the audio stream is MP3-encoded so you need
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to enable LAME support by passing @code{--enable-mp3lame} to configure.
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The mapping is particularly useful for DVD transcoding
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to get the desired audio language.
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NOTE: To see the supported input formats, use @code{ffmpeg -formats}.
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@c man end
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@chapter Invocation
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@section Syntax
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The generic syntax is:
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@example
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@c man begin SYNOPSIS
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ffmpeg [[infile options][@option{-i} @var{infile}]]... @{[outfile options] @var{outfile}@}...
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@c man end
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@end example
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@c man begin DESCRIPTION
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As a general rule, options are applied to the next specified
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file. Therefore, order is important, and you can have the same
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option on the command line multiple times. Each occurrence is
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then applied to the next input or output file.
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* To set the video bitrate of the output file to 64kbit/s:
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@example
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ffmpeg -i input.avi -b 64k output.avi
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@end example
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* To force the frame rate of the input and output file to 24 fps:
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@example
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ffmpeg -r 24 -i input.avi output.avi
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@end example
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* To force the frame rate of the output file to 24 fps:
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@example
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ffmpeg -i input.avi -r 24 output.avi
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@end example
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* To force the frame rate of input file to 1 fps and the output file to 24 fps:
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@example
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ffmpeg -r 1 -i input.avi -r 24 output.avi
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@end example
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The format option may be needed for raw input files.
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By default, FFmpeg tries to convert as losslessly as possible: It
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uses the same audio and video parameters for the outputs as the one
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specified for the inputs.
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@c man end
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@c man begin OPTIONS
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@section Main options
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@table @option
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@item -L
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Show license.
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@item -h
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Show help.
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@item -version
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Show version.
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@item -formats
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Show available formats, codecs, protocols, ...
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@item -f fmt
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Force format.
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@item -i filename
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input filename
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@item -y
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Overwrite output files.
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@item -t duration
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Set the recording time in seconds.
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@code{hh:mm:ss[.xxx]} syntax is also supported.
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@item -fs limit_size
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Set the file size limit.
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@item -ss position
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Seek to given time position in seconds.
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@code{hh:mm:ss[.xxx]} syntax is also supported.
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@item -itsoffset offset
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Set the input time offset in seconds.
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@code{[-]hh:mm:ss[.xxx]} syntax is also supported.
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This option affects all the input files that follow it.
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The offset is added to the timestamps of the input files.
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Specifying a positive offset means that the corresponding
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streams are delayed by 'offset' seconds.
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@item -title string
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Set the title.
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@item -timestamp time
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Set the timestamp.
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@item -author string
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Set the author.
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@item -copyright string
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Set the copyright.
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@item -comment string
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Set the comment.
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@item -album string
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Set the album.
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@item -track number
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Set the track.
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@item -year number
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Set the year.
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@item -v verbose
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Control amount of logging.
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@item -target type
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Specify target file type ("vcd", "svcd", "dvd", "dv", "dv50", "pal-vcd",
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"ntsc-svcd", ... ). All the format options (bitrate, codecs,
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buffer sizes) are then set automatically. You can just type:
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@example
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ffmpeg -i myfile.avi -target vcd /tmp/vcd.mpg
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@end example
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Nevertheless you can specify additional options as long as you know
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they do not conflict with the standard, as in:
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@example
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ffmpeg -i myfile.avi -target vcd -bf 2 /tmp/vcd.mpg
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@end example
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@item -dframes number
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Set the number of data frames to record.
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@item -scodec codec
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Force subtitle codec ('copy' to copy stream).
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@item -newsubtitle
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Add a new subtitle stream to the current output stream.
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@item -slang code
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Set the ISO 639 language code (3 letters) of the current subtitle stream.
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@end table
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@section Video Options
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@table @option
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@item -b bitrate
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Set the video bitrate in bit/s (default = 200 kb/s).
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@item -vframes number
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Set the number of video frames to record.
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@item -r fps
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Set frame rate (Hz value, fraction or abbreviation), (default = 25).
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@item -s size
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Set frame size. The format is @samp{wxh} (ffserver default = 160x128, ffmpeg default = same as source).
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The following abbreviations are recognized:
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@table @samp
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@item sqcif
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128x96
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@item qcif
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176x144
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@item cif
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352x288
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@item 4cif
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704x576
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@end table
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@item -aspect aspect
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Set aspect ratio (4:3, 16:9 or 1.3333, 1.7777).
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@item -croptop size
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Set top crop band size (in pixels).
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@item -cropbottom size
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Set bottom crop band size (in pixels).
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@item -cropleft size
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Set left crop band size (in pixels).
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@item -cropright size
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Set right crop band size (in pixels).
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@item -padtop size
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Set top pad band size (in pixels).
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@item -padbottom size
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Set bottom pad band size (in pixels).
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@item -padleft size
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Set left pad band size (in pixels).
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@item -padright size
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Set right pad band size (in pixels).
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@item -padcolor (hex color)
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Set color of padded bands. The value for padcolor is expressed
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as a six digit hexadecimal number where the first two digits
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represent red, the middle two digits green and last two digits
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blue (default = 000000 (black)).
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@item -vn
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Disable video recording.
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@item -bt tolerance
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Set video bitrate tolerance (in bit/s).
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@item -maxrate bitrate
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Set max video bitrate tolerance (in bit/s).
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@item -minrate bitrate
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Set min video bitrate tolerance (in bit/s).
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@item -bufsize size
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Set rate control buffer size (in bits).
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@item -vcodec codec
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Force video codec to @var{codec}. Use the @code{copy} special value to
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tell that the raw codec data must be copied as is.
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@item -sameq
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Use same video quality as source (implies VBR).
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@item -pass n
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Select the pass number (1 or 2). It is useful to do two pass
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encoding. The statistics of the video are recorded in the first
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pass and the video is generated at the exact requested bitrate
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in the second pass.
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@item -passlogfile file
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Set two pass logfile name to @var{file}.
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@item -newvideo
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Add a new video stream to the current output stream.
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@end table
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@section Advanced Video Options
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@table @option
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@item -pix_fmt format
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Set pixel format.
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@item -g gop_size
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Set the group of pictures size.
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@item -intra
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Use only intra frames.
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@item -vdt n
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Discard threshold.
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@item -qscale q
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Use fixed video quantizer scale (VBR).
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@item -qmin q
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minimum video quantizer scale (VBR)
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@item -qmax q
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maximum video quantizer scale (VBR)
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@item -qdiff q
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maximum difference between the quantizer scales (VBR)
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@item -qblur blur
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video quantizer scale blur (VBR)
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@item -qcomp compression
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video quantizer scale compression (VBR)
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@item -lmin lambda
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minimum video lagrange factor (VBR)
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@item -lmax lambda
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max video lagrange factor (VBR)
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@item -mblmin lambda
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minimum macroblock quantizer scale (VBR)
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@item -mblmax lambda
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maximum macroblock quantizer scale (VBR)
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These four options (lmin, lmax, mblmin, mblmax) use 'lambda' units,
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but you may use the QP2LAMBDA constant to easily convert from 'q' units:
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@example
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ffmpeg -i src.ext -lmax 21*QP2LAMBDA dst.ext
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@end example
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@item -rc_init_cplx complexity
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initial complexity for single pass encoding
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@item -b_qfactor factor
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qp factor between P- and B-frames
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@item -i_qfactor factor
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qp factor between P- and I-frames
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@item -b_qoffset offset
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qp offset between P- and B-frames
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@item -i_qoffset offset
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qp offset between P- and I-frames
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@item -rc_eq equation
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Set rate control equation (@pxref{FFmpeg formula
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evaluator}) (default = @code{tex^qComp}).
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@item -rc_override override
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rate control override for specific intervals
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@item -me method
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Set motion estimation method to @var{method}.
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Available methods are (from lowest to best quality):
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@table @samp
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@item zero
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Try just the (0, 0) vector.
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@item phods
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@item log
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@item x1
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@item epzs
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(default method)
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@item full
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exhaustive search (slow and marginally better than epzs)
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@end table
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@item -dct_algo algo
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Set DCT algorithm to @var{algo}. Available values are:
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@table @samp
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@item 0
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FF_DCT_AUTO (default)
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@item 1
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FF_DCT_FASTINT
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@item 2
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FF_DCT_INT
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@item 3
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FF_DCT_MMX
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@item 4
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FF_DCT_MLIB
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@item 5
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FF_DCT_ALTIVEC
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@end table
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@item -idct_algo algo
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Set IDCT algorithm to @var{algo}. Available values are:
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@table @samp
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@item 0
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FF_IDCT_AUTO (default)
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@item 1
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FF_IDCT_INT
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@item 2
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FF_IDCT_SIMPLE
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@item 3
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FF_IDCT_SIMPLEMMX
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@item 4
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FF_IDCT_LIBMPEG2MMX
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@item 5
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FF_IDCT_PS2
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@item 6
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FF_IDCT_MLIB
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@item 7
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FF_IDCT_ARM
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@item 8
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FF_IDCT_ALTIVEC
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@item 9
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FF_IDCT_SH4
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@item 10
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FF_IDCT_SIMPLEARM
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@end table
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@item -er n
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Set error resilience to @var{n}.
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@table @samp
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@item 1
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FF_ER_CAREFUL (default)
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@item 2
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FF_ER_COMPLIANT
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@item 3
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FF_ER_AGGRESSIVE
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@item 4
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FF_ER_VERY_AGGRESSIVE
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@end table
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@item -ec bit_mask
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Set error concealment to @var{bit_mask}. @var{bit_mask} is a bit mask of
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the following values:
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@table @samp
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@item 1
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FF_EC_GUESS_MVS (default = enabled)
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@item 2
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FF_EC_DEBLOCK (default = enabled)
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@end table
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@item -bf frames
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Use 'frames' B-frames (supported for MPEG-1, MPEG-2 and MPEG-4).
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@item -mbd mode
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macroblock decision
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@table @samp
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@item 0
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FF_MB_DECISION_SIMPLE: Use mb_cmp (cannot change it yet in FFmpeg).
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@item 1
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FF_MB_DECISION_BITS: Choose the one which needs the fewest bits.
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@item 2
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FF_MB_DECISION_RD: rate distortion
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@end table
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@item -4mv
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Use four motion vector by macroblock (MPEG-4 only).
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@item -part
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Use data partitioning (MPEG-4 only).
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@item -bug param
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Work around encoder bugs that are not auto-detected.
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@item -strict strictness
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How strictly to follow the standards.
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@item -aic
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Enable Advanced intra coding (h263+).
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@item -umv
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Enable Unlimited Motion Vector (h263+)
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@item -deinterlace
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Deinterlace pictures.
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@item -ilme
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Force interlacing support in encoder (MPEG-2 and MPEG-4 only).
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Use this option if your input file is interlaced and you want
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to keep the interlaced format for minimum losses.
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The alternative is to deinterlace the input stream with
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@option{-deinterlace}, but deinterlacing introduces losses.
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@item -psnr
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Calculate PSNR of compressed frames.
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@item -vstats
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Dump video coding statistics to @file{vstats_HHMMSS.log}.
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@item -vhook module
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Insert video processing @var{module}. @var{module} contains the module
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name and its parameters separated by spaces.
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@item -top n
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top=1/bottom=0/auto=-1 field first
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@item -dc precision
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Intra_dc_precision.
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@item -vtag fourcc/tag
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Force video tag/fourcc.
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@item -qphist
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Show QP histogram.
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@item -vbsf bitstream filter
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Bitstream filters available are "dump_extra", "remove_extra", "noise".
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@end table
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@section Audio Options
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@table @option
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@item -aframes number
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Set the number of audio frames to record.
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@item -ar freq
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Set the audio sampling frequency (default = 44100 Hz).
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@item -ab bitrate
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Set the audio bitrate in bit/s (default = 64k).
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@item -ac channels
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Set the number of audio channels (default = 1).
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@item -an
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Disable audio recording.
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@item -acodec codec
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Force audio codec to @var{codec}. Use the @code{copy} special value to
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specify that the raw codec data must be copied as is.
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@item -newaudio
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Add a new audio track to the output file. If you want to specify parameters,
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do so before @code{-newaudio} (@code{-acodec}, @code{-ab}, etc..).
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Mapping will be done automatically, if the number of output streams is equal to
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the number of input streams, else it will pick the first one that matches. You
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can override the mapping using @code{-map} as usual.
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Example:
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@example
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ffmpeg -i file.mpg -vcodec copy -acodec ac3 -ab 384k test.mpg -acodec mp2 -ab 192k -newaudio
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@end example
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@item -alang code
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Set the ISO 639 language code (3 letters) of the current audio stream.
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@end table
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@section Advanced Audio options:
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@table @option
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@item -atag fourcc/tag
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Force audio tag/fourcc.
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@item -absf bitstream filter
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Bitstream filters available are "dump_extra", "remove_extra", "noise", "mp3comp", "mp3decomp".
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@end table
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@section Subtitle options:
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@table @option
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@item -scodec codec
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Force subtitle codec ('copy' to copy stream).
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@item -newsubtitle
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Add a new subtitle stream to the current output stream.
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@item -slang code
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Set the ISO 639 language code (3 letters) of the current subtitle stream.
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@end table
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@section Audio/Video grab options
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@table @option
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@item -vc channel
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Set video grab channel (DV1394 only).
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@item -tvstd standard
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Set television standard (NTSC, PAL (SECAM)).
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@item -isync
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Synchronize read on input.
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@end table
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@section Advanced options
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@table @option
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@item -map input stream id[:input stream id]
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Set stream mapping from input streams to output streams.
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Just enumerate the input streams in the order you want them in the output.
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[input stream id] sets the (input) stream to sync against.
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@item -map_meta_data outfile:infile
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Set meta data information of outfile from infile.
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@item -debug
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Print specific debug info.
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@item -benchmark
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Add timings for benchmarking.
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@item -dump
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Dump each input packet.
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@item -hex
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When dumping packets, also dump the payload.
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@item -bitexact
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Only use bit exact algorithms (for codec testing).
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@item -ps size
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Set packet size in bits.
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@item -re
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Read input at native frame rate. Mainly used to simulate a grab device.
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@item -loop_input
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Loop over the input stream. Currently it works only for image
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streams. This option is used for automatic FFserver testing.
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@item -loop_output number_of_times
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Repeatedly loop output for formats that support looping such as animated GIF
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(0 will loop the output infinitely).
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@item -threads count
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Thread count.
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@item -vsync parameter
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Video sync method. Video will be stretched/squeezed to match the timestamps,
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it is done by duplicating and dropping frames. With -map you can select from
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which stream the timestamps should be taken. You can leave either video or
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audio unchanged and sync the remaining stream(s) to the unchanged one.
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@item -async samples_per_second
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Audio sync method. "Stretches/squeezes" the audio stream to match the timestamps,
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the parameter is the maximum samples per second by which the audio is changed.
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-async 1 is a special case where only the start of the audio stream is corrected
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without any later correction.
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@end table
660

    
661
@node FFmpeg formula evaluator
662
@section FFmpeg formula evaluator
663

    
664
When evaluating a rate control string, FFmpeg uses an internal formula
665
evaluator.
666

    
667
The following binary operators are available: @code{+}, @code{-},
668
@code{*}, @code{/}, @code{^}.
669

    
670
The following unary operators are available: @code{+}, @code{-},
671
@code{(...)}.
672

    
673
The following functions are available:
674
@table @var
675
@item sinh(x)
676
@item cosh(x)
677
@item tanh(x)
678
@item sin(x)
679
@item cos(x)
680
@item tan(x)
681
@item exp(x)
682
@item log(x)
683
@item squish(x)
684
@item gauss(x)
685
@item abs(x)
686
@item max(x, y)
687
@item min(x, y)
688
@item gt(x, y)
689
@item lt(x, y)
690
@item eq(x, y)
691
@item bits2qp(bits)
692
@item qp2bits(qp)
693
@end table
694

    
695
The following constants are available:
696
@table @var
697
@item PI
698
@item E
699
@item iTex
700
@item pTex
701
@item tex
702
@item mv
703
@item fCode
704
@item iCount
705
@item mcVar
706
@item var
707
@item isI
708
@item isP
709
@item isB
710
@item avgQP
711
@item qComp
712
@item avgIITex
713
@item avgPITex
714
@item avgPPTex
715
@item avgBPTex
716
@item avgTex
717
@end table
718

    
719
@c man end
720

    
721
@ignore
722

    
723
@setfilename ffmpeg
724
@settitle FFmpeg video converter
725

    
726
@c man begin SEEALSO
727
ffserver(1), ffplay(1) and the HTML documentation of @file{ffmpeg}.
728
@c man end
729

    
730
@c man begin AUTHOR
731
Fabrice Bellard
732
@c man end
733

    
734
@end ignore
735

    
736
@section Protocols
737

    
738
The filename can be @file{-} to read from standard input or to write
739
to standard output.
740

    
741
FFmpeg also handles many protocols specified with an URL syntax.
742

    
743
Use 'ffmpeg -formats' to see a list of the supported protocols.
744

    
745
The protocol @code{http:} is currently used only to communicate with
746
FFserver (see the FFserver documentation). When FFmpeg will be a
747
video player it will also be used for streaming :-)
748

    
749
@chapter Tips
750

    
751
@itemize
752
@item For streaming at very low bitrate application, use a low frame rate
753
and a small GOP size. This is especially true for RealVideo where
754
the Linux player does not seem to be very fast, so it can miss
755
frames. An example is:
756

    
757
@example
758
ffmpeg -g 3 -r 3 -t 10 -b 50k -s qcif -f rv10 /tmp/b.rm
759
@end example
760

    
761
@item  The parameter 'q' which is displayed while encoding is the current
762
quantizer. The value 1 indicates that a very good quality could
763
be achieved. The value 31 indicates the worst quality. If q=31 appears
764
too often, it means that the encoder cannot compress enough to meet
765
your bitrate. You must either increase the bitrate, decrease the
766
frame rate or decrease the frame size.
767

    
768
@item If your computer is not fast enough, you can speed up the
769
compression at the expense of the compression ratio. You can use
770
'-me zero' to speed up motion estimation, and '-intra' to disable
771
motion estimation completely (you have only I-frames, which means it
772
is about as good as JPEG compression).
773

    
774
@item To have very low audio bitrates, reduce the sampling frequency
775
(down to 22050 kHz for MPEG audio, 22050 or 11025 for AC3).
776

    
777
@item To have a constant quality (but a variable bitrate), use the option
778
'-qscale n' when 'n' is between 1 (excellent quality) and 31 (worst
779
quality).
780

    
781
@item When converting video files, you can use the '-sameq' option which
782
uses the same quality factor in the encoder as in the decoder.
783
It allows almost lossless encoding.
784

    
785
@end itemize
786

    
787

    
788
@chapter external libraries
789

    
790
FFmpeg can be hooked up with a number of external libraries to add support
791
for more formats. None of them are used by default, their use has to be
792
explicitly requested by passing the appropriate flags to @file{./configure}.
793

    
794
@section AMR
795

    
796
AMR comes in two different flavors, WB and NB. FFmpeg can make use of the
797
AMR WB (floating-point mode) and the AMR NB (both floating-point and
798
fixed-point mode) reference decoders and encoders.
799

    
800
@itemize
801

    
802
@item For AMR WB floating-point and AMR NB floating point support, go to
803
@url{http://www.penguin.cz/~utx/amr} and follow the instructions for building
804
the libraries. Pass @code{--enable-amr-nb} and/or @code{--enable-amr-wb} to
805
configure to enable the libraries.
806

    
807
@item For AMR NB fixed-point download TS26.073 REL-6 V6.0.0 from
808
@url{http://www.3gpp.org/ftp/Specs/archive/26_series/26.073/26073-600.zip}
809
and extract the source to the directory @file{libavcodec/amr}.
810
You must also add @code{-DMMS_IO} to @code{CFLAGS} in
811
@file{libavcodec/amr/makefile}, i.e.
812
``@code{CFLAGS = -Wall -pedantic-errors -I. $(CFLAGS_$(MODE)) -D$(VAD) -DMMS_IO}''.
813
Pass @code{--enable-amr-nb-fixed} to configure to enable it.
814

    
815
@end itemize
816

    
817

    
818
@chapter Supported File Formats and Codecs
819

    
820
You can use the @code{-formats} option to have an exhaustive list.
821

    
822
@section File Formats
823

    
824
FFmpeg supports the following file formats through the @code{libavformat}
825
library:
826

    
827
@multitable @columnfractions .4 .1 .1 .4
828
@item Supported File Format @tab Encoding @tab Decoding @tab Comments
829
@item MPEG audio @tab X @tab X
830
@item MPEG-1 systems @tab X  @tab  X
831
@tab muxed audio and video
832
@item MPEG-2 PS @tab X  @tab  X
833
@tab also known as @code{VOB} file
834
@item MPEG-2 TS @tab    @tab  X
835
@tab also known as DVB Transport Stream
836
@item ASF@tab X @tab X
837
@item AVI@tab X @tab X
838
@item WAV@tab X @tab X
839
@item Macromedia Flash@tab X @tab X
840
@tab Only embedded audio is decoded.
841
@item FLV              @tab  X @tab X
842
@tab Macromedia Flash video files
843
@item Real Audio and Video @tab X @tab X
844
@item Raw AC3 @tab X  @tab  X
845
@item Raw MJPEG @tab X  @tab  X
846
@item Raw MPEG video @tab X  @tab  X
847
@item Raw PCM8/16 bits, mulaw/Alaw@tab X  @tab  X
848
@item Raw CRI ADX audio @tab X  @tab  X
849
@item Raw Shorten audio @tab    @tab  X
850
@item SUN AU format @tab X  @tab  X
851
@item NUT @tab X @tab X @tab NUT Open Container Format
852
@item QuickTime        @tab X @tab  X
853
@item MPEG-4           @tab X @tab  X
854
@tab MPEG-4 is a variant of QuickTime.
855
@item Raw MPEG4 video  @tab  X @tab  X
856
@item DV               @tab  X @tab  X
857
@item 4xm              @tab    @tab X
858
@tab 4X Technologies format, used in some games.
859
@item Playstation STR  @tab    @tab X
860
@item Id RoQ           @tab    @tab X
861
@tab Used in Quake III, Jedi Knight 2, other computer games.
862
@item Interplay MVE    @tab    @tab X
863
@tab Format used in various Interplay computer games.
864
@item WC3 Movie        @tab    @tab X
865
@tab Multimedia format used in Origin's Wing Commander III computer game.
866
@item Sega FILM/CPK    @tab    @tab X
867
@tab Used in many Sega Saturn console games.
868
@item Westwood Studios VQA/AUD  @tab    @tab X
869
@tab Multimedia formats used in Westwood Studios games.
870
@item Id Cinematic (.cin) @tab    @tab X
871
@tab Used in Quake II.
872
@item FLIC format      @tab    @tab X
873
@tab .fli/.flc files
874
@item Sierra VMD       @tab    @tab X
875
@tab Used in Sierra CD-ROM games.
876
@item Sierra Online    @tab    @tab X
877
@tab .sol files used in Sierra Online games.
878
@item Matroska         @tab    @tab X
879
@item Electronic Arts Multimedia    @tab    @tab X
880
@tab Used in various EA games; files have extensions like WVE and UV2.
881
@item Nullsoft Video (NSV) format @tab    @tab X
882
@item ADTS AAC audio @tab X @tab X
883
@item Creative VOC @tab X @tab X @tab Created for the Sound Blaster Pro.
884
@item American Laser Games MM  @tab    @tab X
885
@tab Multimedia format used in games like Mad Dog McCree
886
@item AVS @tab    @tab X
887
@tab Multimedia format used by the Creature Shock game.
888
@item Smacker @tab    @tab X
889
@tab Multimedia format used by many games.
890
@item GXF @tab  X @tab X
891
@tab General eXchange Format SMPTE 360M, used by Thomson Grass Valley playout servers.
892
@item CIN @tab    @tab X
893
@tab Multimedia format used by Delphine Software games.
894
@item MXF @tab    @tab X
895
@tab Material eXchange Format SMPTE 377M, used by D-Cinema, broadcast industry.
896
@item SEQ @tab    @tab X
897
@tab Tiertex .seq files used in the DOS CDROM version of the game Flashback.
898
@item DXA @tab    @tab X
899
@tab This format is used in non-Windows version of Feeble Files game and
900
different game cutscenes repacked for use with ScummVM.
901
@item THP @tab    @tab X
902
@tab Used on the Nintendo GameCube.
903
@item C93 @tab    @tab X
904
@tab Used in the game Cyberia from Interplay.
905
@item Bethsoft VID @tab    @tab X
906
@tab Used in some games from Bethesda Softworks.
907
@item CRYO APC @tab    @tab X
908
@tab Audio format used in some games by CRYO Interactive Entertainment.
909
@end multitable
910

    
911
@code{X} means that encoding (resp. decoding) is supported.
912

    
913
@section Image Formats
914

    
915
FFmpeg can read and write images for each frame of a video sequence. The
916
following image formats are supported:
917

    
918
@multitable @columnfractions .4 .1 .1 .4
919
@item Supported Image Format @tab Encoding @tab Decoding @tab Comments
920
@item PGM, PPM     @tab X @tab X
921
@item PAM          @tab X @tab X @tab PAM is a PNM extension with alpha support.
922
@item PGMYUV       @tab X @tab X @tab PGM with U and V components in YUV 4:2:0
923
@item JPEG         @tab X @tab X @tab Progressive JPEG is not supported.
924
@item .Y.U.V       @tab X @tab X @tab one raw file per component
925
@item animated GIF @tab X @tab X @tab Only uncompressed GIFs are generated.
926
@item PNG          @tab X @tab X @tab 2 bit and 4 bit/pixel not supported yet.
927
@item Targa        @tab   @tab X @tab Targa (.TGA) image format.
928
@item TIFF         @tab X @tab X @tab YUV, JPEG and some extension is not supported yet.
929
@item SGI          @tab X @tab X @tab SGI RGB image format
930
@end multitable
931

    
932
@code{X} means that encoding (resp. decoding) is supported.
933

    
934
@section Video Codecs
935

    
936
@multitable @columnfractions .4 .1 .1 .4
937
@item Supported Codec @tab Encoding @tab Decoding @tab Comments
938
@item MPEG-1 video           @tab  X  @tab  X
939
@item MPEG-2 video           @tab  X  @tab  X
940
@item MPEG-4                 @tab  X  @tab  X
941
@item MSMPEG4 V1             @tab  X  @tab  X
942
@item MSMPEG4 V2             @tab  X  @tab  X
943
@item MSMPEG4 V3             @tab  X  @tab  X
944
@item WMV7                   @tab  X  @tab  X
945
@item WMV8                   @tab  X  @tab  X @tab not completely working
946
@item WMV9                   @tab     @tab  X @tab not completely working
947
@item VC1                    @tab     @tab  X
948
@item H.261                  @tab  X  @tab  X
949
@item H.263(+)               @tab  X  @tab  X @tab also known as RealVideo 1.0
950
@item H.264                  @tab     @tab  X
951
@item RealVideo 1.0          @tab  X  @tab  X
952
@item RealVideo 2.0          @tab  X  @tab  X
953
@item MJPEG                  @tab  X  @tab  X
954
@item lossless MJPEG         @tab  X  @tab  X
955
@item JPEG-LS                @tab  X  @tab  X @tab fourcc: MJLS, lossless and near-lossless is supported
956
@item Apple MJPEG-B          @tab     @tab  X
957
@item Sunplus MJPEG          @tab     @tab  X @tab fourcc: SP5X
958
@item DV                     @tab  X  @tab  X
959
@item HuffYUV                @tab  X  @tab  X
960
@item FFmpeg Video 1         @tab  X  @tab  X @tab experimental lossless codec (fourcc: FFV1)
961
@item FFmpeg Snow            @tab  X  @tab  X @tab experimental wavelet codec (fourcc: SNOW)
962
@item Asus v1                @tab  X  @tab  X @tab fourcc: ASV1
963
@item Asus v2                @tab  X  @tab  X @tab fourcc: ASV2
964
@item Creative YUV           @tab     @tab  X @tab fourcc: CYUV
965
@item Sorenson Video 1       @tab  X  @tab  X @tab fourcc: SVQ1
966
@item Sorenson Video 3       @tab     @tab  X @tab fourcc: SVQ3
967
@item On2 VP3                @tab     @tab  X @tab still experimental
968
@item On2 VP5                @tab     @tab  X @tab fourcc: VP50
969
@item On2 VP6                @tab     @tab  X @tab fourcc: VP60,VP61,VP62
970
@item Theora                 @tab  X  @tab  X @tab still experimental
971
@item Intel Indeo 3          @tab     @tab  X
972
@item FLV                    @tab  X  @tab  X @tab Sorenson H.263 used in Flash
973
@item Flash Screen Video     @tab  X  @tab  X @tab fourcc: FSV1
974
@item ATI VCR1               @tab     @tab  X @tab fourcc: VCR1
975
@item ATI VCR2               @tab     @tab  X @tab fourcc: VCR2
976
@item Cirrus Logic AccuPak   @tab     @tab  X @tab fourcc: CLJR
977
@item 4X Video               @tab     @tab  X @tab Used in certain computer games.
978
@item Sony Playstation MDEC  @tab     @tab  X
979
@item Id RoQ                 @tab     @tab  X @tab Used in Quake III, Jedi Knight 2, other computer games.
980
@item Xan/WC3                @tab     @tab  X @tab Used in Wing Commander III .MVE files.
981
@item Interplay Video        @tab     @tab  X @tab Used in Interplay .MVE files.
982
@item Apple Animation        @tab     @tab  X @tab fourcc: 'rle '
983
@item Apple Graphics         @tab     @tab  X @tab fourcc: 'smc '
984
@item Apple Video            @tab     @tab  X @tab fourcc: rpza
985
@item Apple QuickDraw        @tab     @tab  X @tab fourcc: qdrw
986
@item Cinepak                @tab     @tab  X
987
@item Microsoft RLE          @tab     @tab  X
988
@item Microsoft Video-1      @tab     @tab  X
989
@item Westwood VQA           @tab     @tab  X
990
@item Id Cinematic Video     @tab     @tab  X @tab Used in Quake II.
991
@item Planar RGB             @tab     @tab  X @tab fourcc: 8BPS
992
@item FLIC video             @tab     @tab  X
993
@item Duck TrueMotion v1     @tab     @tab  X @tab fourcc: DUCK
994
@item Duck TrueMotion v2     @tab     @tab  X @tab fourcc: TM20
995
@item VMD Video              @tab     @tab  X @tab Used in Sierra VMD files.
996
@item MSZH                   @tab     @tab  X @tab Part of LCL
997
@item ZLIB                   @tab  X  @tab  X @tab Part of LCL, encoder experimental
998
@item TechSmith Camtasia     @tab     @tab  X @tab fourcc: TSCC
999
@item IBM Ultimotion         @tab     @tab  X @tab fourcc: ULTI
1000
@item Miro VideoXL           @tab     @tab  X @tab fourcc: VIXL
1001
@item QPEG                   @tab     @tab  X @tab fourccs: QPEG, Q1.0, Q1.1
1002
@item LOCO                   @tab     @tab  X @tab
1003
@item Winnov WNV1            @tab     @tab  X @tab
1004
@item Autodesk Animator Studio Codec  @tab     @tab  X @tab fourcc: AASC
1005
@item Fraps FPS1             @tab     @tab  X @tab
1006
@item CamStudio              @tab     @tab  X @tab fourcc: CSCD
1007
@item American Laser Games Video  @tab    @tab X @tab Used in games like Mad Dog McCree
1008
@item ZMBV                   @tab   X @tab  X @tab Encoder works only on PAL8
1009
@item AVS Video              @tab     @tab  X @tab Video encoding used by the Creature Shock game.
1010
@item Smacker Video          @tab     @tab  X @tab Video encoding used in Smacker.
1011
@item RTjpeg                 @tab     @tab  X @tab Video encoding used in NuppelVideo files.
1012
@item KMVC                   @tab     @tab  X @tab Codec used in Worms games.
1013
@item VMware Video           @tab     @tab  X @tab Codec used in videos captured by VMware.
1014
@item Cin Video              @tab     @tab  X @tab Codec used in Delphine Software games.
1015
@item Tiertex Seq Video      @tab     @tab  X @tab Codec used in DOS CDROM FlashBack game.
1016
@item DXA Video              @tab     @tab  X @tab Codec originally used in Feeble Files game.
1017
@item AVID DNxHD             @tab     @tab  X @tab aka SMPTE VC3
1018
@item C93 Video              @tab     @tab  X @tab Codec used in Cyberia game.
1019
@item THP                    @tab     @tab  X @tab Used on the Nintendo GameCube.
1020
@item Bethsoft VID           @tab     @tab  X @tab Used in some games from Bethesda Softworks.
1021
@end multitable
1022

    
1023
@code{X} means that encoding (resp. decoding) is supported.
1024

    
1025
@section Audio Codecs
1026

    
1027
@multitable @columnfractions .4 .1 .1 .1 .7
1028
@item Supported Codec @tab Encoding @tab Decoding @tab Comments
1029
@item MPEG audio layer 2     @tab  IX  @tab  IX
1030
@item MPEG audio layer 1/3   @tab IX   @tab  IX
1031
@tab MP3 encoding is supported through the external library LAME.
1032
@item AC3                    @tab  IX  @tab  IX
1033
@tab liba52 is used internally for decoding.
1034
@item Vorbis                 @tab  X   @tab  X
1035
@item WMA V1/V2              @tab X    @tab X
1036
@item AAC                    @tab X    @tab X
1037
@tab Supported through the external library libfaac/libfaad.
1038
@item Microsoft ADPCM        @tab X    @tab X
1039
@item MS IMA ADPCM           @tab X    @tab X
1040
@item QT IMA ADPCM           @tab      @tab X
1041
@item 4X IMA ADPCM           @tab      @tab X
1042
@item G.726  ADPCM           @tab X    @tab X
1043
@item Duck DK3 IMA ADPCM     @tab      @tab X
1044
@tab Used in some Sega Saturn console games.
1045
@item Duck DK4 IMA ADPCM     @tab      @tab X
1046
@tab Used in some Sega Saturn console games.
1047
@item Westwood Studios IMA ADPCM @tab      @tab X
1048
@tab Used in Westwood Studios games like Command and Conquer.
1049
@item SMJPEG IMA ADPCM       @tab      @tab X
1050
@tab Used in certain Loki game ports.
1051
@item CD-ROM XA ADPCM        @tab      @tab X
1052
@item CRI ADX ADPCM          @tab X    @tab X
1053
@tab Used in Sega Dreamcast games.
1054
@item Electronic Arts ADPCM  @tab      @tab X
1055
@tab Used in various EA titles.
1056
@item Creative ADPCM         @tab      @tab X
1057
@tab 16 -> 4, 8 -> 4, 8 -> 3, 8 -> 2
1058
@item THP ADPCM              @tab      @tab X
1059
@tab Used on the Nintendo GameCube.
1060
@item RA144                  @tab      @tab X
1061
@tab Real 14400 bit/s codec
1062
@item RA288                  @tab      @tab X
1063
@tab Real 28800 bit/s codec
1064
@item RADnet                 @tab X    @tab IX
1065
@tab Real low bitrate AC3 codec, liba52 is used for decoding.
1066
@item AMR-NB                 @tab X    @tab X
1067
@tab Supported through an external library.
1068
@item AMR-WB                 @tab X    @tab X
1069
@tab Supported through an external library.
1070
@item DV audio               @tab      @tab X
1071
@item Id RoQ DPCM            @tab      @tab X
1072
@tab Used in Quake III, Jedi Knight 2, other computer games.
1073
@item Interplay MVE DPCM     @tab      @tab X
1074
@tab Used in various Interplay computer games.
1075
@item Xan DPCM               @tab      @tab X
1076
@tab Used in Origin's Wing Commander IV AVI files.
1077
@item Sierra Online DPCM     @tab      @tab X
1078
@tab Used in Sierra Online game audio files.
1079
@item Apple MACE 3           @tab      @tab X
1080
@item Apple MACE 6           @tab      @tab X
1081
@item FLAC lossless audio    @tab X    @tab X
1082
@item Shorten lossless audio @tab      @tab X
1083
@item Apple lossless audio   @tab      @tab X
1084
@tab QuickTime fourcc 'alac'
1085
@item FFmpeg Sonic           @tab X    @tab X
1086
@tab experimental lossy/lossless codec
1087
@item Qdesign QDM2           @tab      @tab X
1088
@tab there are still some distortions
1089
@item Real COOK              @tab      @tab X
1090
@tab All versions except 5.1 are supported
1091
@item DSP Group TrueSpeech   @tab      @tab X
1092
@item True Audio (TTA)       @tab      @tab X
1093
@item Smacker Audio          @tab      @tab X
1094
@item WavPack Audio          @tab      @tab X
1095
@item Cin Audio              @tab      @tab X
1096
@tab Codec used in Delphine Software games.
1097
@item Intel Music Coder      @tab      @tab X
1098
@item Musepack               @tab      @tab X
1099
@tab Only SV7 is supported
1100
@item DT$ Coherent Audio     @tab      @tab X
1101
@item ATRAC 3                @tab      @tab X
1102
@end multitable
1103

    
1104
@code{X} means that encoding (resp. decoding) is supported.
1105

    
1106
@code{I} means that an integer-only version is available, too (ensures high
1107
performance on systems without hardware floating point support).
1108

    
1109
@chapter Platform Specific information
1110

    
1111
@section BSD
1112

    
1113
BSD make will not build FFmpeg, you need to install and use GNU Make
1114
(@file{gmake}).
1115

    
1116
@section Windows
1117

    
1118
To get help and instructions for using FFmpeg under Windows, check out
1119
the FFmpeg Windows Help Forum at
1120
@url{http://arrozcru.no-ip.org/ffmpeg/}.
1121

    
1122
@subsection Native Windows compilation
1123

    
1124
@itemize
1125
@item Install the current versions of MSYS and MinGW from
1126
@url{http://www.mingw.org/}. You can find detailed installation
1127
instructions in the download section and the FAQ.
1128

    
1129
NOTE: Use at least bash 3.1. Older versions are known to be failing on the
1130
configure script.
1131

    
1132
@item If you want to test the FFplay, also download
1133
the MinGW development library of SDL 1.2.x
1134
(@file{SDL-devel-1.2.x-mingw32.tar.gz}) from
1135
@url{http://www.libsdl.org}. Unpack it in a temporary directory, and
1136
unpack the archive @file{i386-mingw32msvc.tar.gz} in the MinGW tool
1137
directory. Edit the @file{sdl-config} script so that it gives the
1138
correct SDL directory when invoked.
1139

    
1140
@item Extract the current version of FFmpeg.
1141

    
1142
@item Start the MSYS shell (file @file{msys.bat}).
1143

    
1144
@item Change to the FFmpeg directory and follow
1145
 the instructions of how to compile FFmpeg (file
1146
@file{INSTALL}). Usually, launching @file{./configure} and @file{make}
1147
suffices. If you have problems using SDL, verify that
1148
@file{sdl-config} can be launched from the MSYS command line.
1149

    
1150
@item You can install FFmpeg in @file{Program Files/FFmpeg} by typing
1151
@file{make install}. Do not forget to copy @file{SDL.dll} to the place
1152
you launch @file{ffplay} from.
1153

    
1154
@end itemize
1155

    
1156
Notes:
1157
@itemize
1158

    
1159
@item The target @file{make wininstaller} can be used to create a
1160
Nullsoft based Windows installer for FFmpeg and FFplay. @file{SDL.dll}
1161
must be copied to the FFmpeg directory in order to build the
1162
installer.
1163

    
1164
@item By using @code{./configure --enable-shared} when configuring FFmpeg,
1165
you can build @file{avcodec.dll} and @file{avformat.dll}. With
1166
@code{make install} you install the FFmpeg DLLs and the associated
1167
headers in @file{Program Files/FFmpeg}.
1168

    
1169
@item Visual C++ compatibility: If you used @code{./configure --enable-shared}
1170
when configuring FFmpeg, FFmpeg tries to use the Microsoft Visual
1171
C++ @code{lib} tool to build @code{avcodec.lib} and
1172
@code{avformat.lib}. With these libraries you can link your Visual C++
1173
code directly with the FFmpeg DLLs (see below).
1174

    
1175
@end itemize
1176

    
1177
@subsection Visual C++ compatibility
1178

    
1179
FFmpeg will not compile under Visual C++ -- and it has too many
1180
dependencies on the GCC compiler to make a port viable. However,
1181
if you want to use the FFmpeg libraries in your own applications,
1182
you can still compile those applications using Visual C++. An
1183
important restriction to this is that you have to use the
1184
dynamically linked versions of the FFmpeg libraries (i.e. the
1185
DLLs), and you have to make sure that Visual-C++-compatible
1186
import libraries are created during the FFmpeg build process.
1187

    
1188
This description of how to use the FFmpeg libraries with Visual C++ is
1189
based on Visual C++ 2005 Express Edition Beta 2. If you have a different
1190
version, you might have to modify the procedures slightly.
1191

    
1192
Here are the step-by-step instructions for building the FFmpeg libraries
1193
so they can be used with Visual C++:
1194

    
1195
@enumerate
1196

    
1197
@item Install Visual C++ (if you have not done so already).
1198

    
1199
@item Install MinGW and MSYS as described above.
1200

    
1201
@item Add a call to @file{vcvars32.bat} (which sets up the environment
1202
variables for the Visual C++ tools) as the first line of
1203
@file{msys.bat}. The standard location for @file{vcvars32.bat} is
1204
@file{C:\Program Files\Microsoft Visual Studio 8\VC\bin\vcvars32.bat},
1205
and the standard location for @file{msys.bat} is
1206
@file{C:\msys\1.0\msys.bat}. If this corresponds to your setup, add the
1207
following line as the first line of @file{msys.bat}:
1208

    
1209
@code{call "C:\Program Files\Microsoft Visual Studio 8\VC\bin\vcvars32.bat"}
1210

    
1211
@item Start the MSYS shell (file @file{msys.bat}) and type @code{link.exe}.
1212
If you get a help message with the command line options of @code{link.exe},
1213
this means your environment variables are set up correctly, the
1214
Microsoft linker is on the path and will be used by FFmpeg to
1215
create Visual-C++-compatible import libraries.
1216

    
1217
@item Extract the current version of FFmpeg and change to the FFmpeg directory.
1218

    
1219
@item Type the command
1220
@code{./configure --enable-shared --disable-static --enable-memalign-hack}
1221
to configure and, if that did not produce any errors,
1222
type @code{make} to build FFmpeg.
1223

    
1224
@item The subdirectories @file{libavformat}, @file{libavcodec}, and
1225
@file{libavutil} should now contain the files @file{avformat.dll},
1226
@file{avformat.lib}, @file{avcodec.dll}, @file{avcodec.lib},
1227
@file{avutil.dll}, and @file{avutil.lib}, respectively. Copy the three
1228
DLLs to your System32 directory (typically @file{C:\Windows\System32}).
1229

    
1230
@end enumerate
1231

    
1232
And here is how to use these libraries with Visual C++:
1233

    
1234
@enumerate
1235

    
1236
@item Create a new console application ("File / New / Project") and then
1237
select "Win32 Console Application". On the appropriate page of the
1238
Application Wizard, uncheck the "Precompiled headers" option.
1239

    
1240
@item Write the source code for your application, or, for testing, just
1241
copy the code from an existing sample application into the source file
1242
that Visual C++ has already created for you. (Note that your source
1243
filehas to have a @code{.cpp} extension; otherwise, Visual C++ will not
1244
compile the FFmpeg headers correctly because in C mode, it does not
1245
recognize the @code{inline} keyword.)  For example, you can copy
1246
@file{output_example.c} from the FFmpeg distribution (but you will
1247
have to make minor modifications so the code will compile under
1248
C++, see below).
1249

    
1250
@item Open the "Project / Properties" dialog box. In the "Configuration"
1251
combo box, select "All Configurations" so that the changes you make will
1252
affect both debug and release builds. In the tree view on the left hand
1253
side, select "C/C++ / General", then edit the "Additional Include
1254
Directories" setting to contain the complete paths to the
1255
@file{libavformat}, @file{libavcodec}, and @file{libavutil}
1256
subdirectories of your FFmpeg directory. Note that the directories have
1257
to be separated using semicolons. Now select "Linker / General" from the
1258
tree view and edit the "Additional Library Directories" setting to
1259
contain the same three directories.
1260

    
1261
@item Still in the "Project / Properties" dialog box, select "Linker / Input"
1262
from the tree view, then add the files @file{avformat.lib},
1263
@file{avcodec.lib}, and @file{avutil.lib} to the end of the "Additional
1264
Dependencies". Note that the names of the libraries have to be separated
1265
using spaces.
1266

    
1267
@item Now, select "C/C++ / Code Generation" from the tree view. Select
1268
"Debug" in the "Configuration" combo box. Make sure that "Runtime
1269
Library" is set to "Multi-threaded Debug DLL". Then, select "Release" in
1270
the "Configuration" combo box and make sure that "Runtime Library" is
1271
set to "Multi-threaded DLL".
1272

    
1273
@item Click "OK" to close the "Project / Properties" dialog box and build
1274
the application. Hopefully, it should compile and run cleanly. If you
1275
used @file{output_example.c} as your sample application, you will get a
1276
few compiler errors, but they are easy to fix. The first type of error
1277
occurs because Visual C++ does not allow an @code{int} to be converted to
1278
an @code{enum} without a cast. To solve the problem, insert the required
1279
casts (this error occurs once for a @code{CodecID} and once for a
1280
@code{CodecType}).  The second type of error occurs because C++ requires
1281
the return value of @code{malloc} to be cast to the exact type of the
1282
pointer it is being assigned to. Visual C++ will complain that, for
1283
example, @code{(void *)} is being assigned to @code{(uint8_t *)} without
1284
an explicit cast. So insert an explicit cast in these places to silence
1285
the compiler. The third type of error occurs because the @code{snprintf}
1286
library function is called @code{_snprintf} under Visual C++.  So just
1287
add an underscore to fix the problem. With these changes,
1288
@file{output_example.c} should compile under Visual C++, and the
1289
resulting executable should produce valid video files.
1290

    
1291
@end enumerate
1292

    
1293
@subsection Cross compilation for Windows with Linux
1294

    
1295
You must use the MinGW cross compilation tools available at
1296
@url{http://www.mingw.org/}.
1297

    
1298
Then configure FFmpeg with the following options:
1299
@example
1300
./configure --target-os=mingw32 --cross-prefix=i386-mingw32msvc-
1301
@end example
1302
(you can change the cross-prefix according to the prefix chosen for the
1303
MinGW tools).
1304

    
1305
Then you can easily test FFmpeg with Wine
1306
(@url{http://www.winehq.com/}).
1307

    
1308
@subsection Compilation under Cygwin
1309

    
1310
Cygwin works very much like Unix.
1311

    
1312
Just install your Cygwin with all the "Base" packages, plus the
1313
following "Devel" ones:
1314
@example
1315
binutils, gcc-core, make, subversion
1316
@end example
1317

    
1318
Do not install binutils-20060709-1 (they are buggy on shared builds);
1319
use binutils-20050610-1 instead.
1320

    
1321
Then run
1322

    
1323
@example
1324
./configure --enable-static --disable-shared
1325
@end example
1326

    
1327
to make a static build or
1328

    
1329
@example
1330
./configure --enable-shared --disable-static
1331
@end example
1332

    
1333
to build shared libraries.
1334

    
1335
If you want to build FFmpeg with additional libraries, download Cygwin
1336
"Devel" packages for Ogg and Vorbis from any Cygwin packages repository
1337
and/or SDL, xvid, faac, faad2 packages from Cygwin Ports,
1338
(@url{http://cygwinports.dotsrc.org/}).
1339

    
1340
@subsection Crosscompilation for Windows under Cygwin
1341

    
1342
With Cygwin you can create Windows binaries that do not need the cygwin1.dll.
1343

    
1344
Just install your Cygwin as explained before, plus these additional
1345
"Devel" packages:
1346
@example
1347
gcc-mingw-core, mingw-runtime, mingw-zlib
1348
@end example
1349

    
1350
and add some special flags to your configure invocation.
1351

    
1352
For a static build run
1353
@example
1354
./configure --target-os=mingw32 --enable-memalign-hack --enable-static --disable-shared --extra-cflags=-mno-cygwin --extra-libs=-mno-cygwin
1355
@end example
1356

    
1357
and for a build with shared libraries
1358
@example
1359
./configure --target-os=mingw32 --enable-memalign-hack --enable-shared --disable-static --extra-cflags=-mno-cygwin --extra-libs=-mno-cygwin
1360
@end example
1361

    
1362
@section BeOS
1363

    
1364
The configure script should guess the configuration itself.
1365
Networking support is currently not finished.
1366
errno issues fixed by Andrew Bachmann.
1367

    
1368
Old stuff:
1369

    
1370
Fran├žois Revol - revol at free dot fr - April 2002
1371

    
1372
The configure script should guess the configuration itself,
1373
however I still did not test building on the net_server version of BeOS.
1374

    
1375
FFserver is broken (needs poll() implementation).
1376

    
1377
There are still issues with errno codes, which are negative in BeOS, and
1378
that FFmpeg negates when returning. This ends up turning errors into
1379
valid results, then crashes.
1380
(To be fixed)
1381

    
1382
@chapter Developers Guide
1383

    
1384
@section API
1385
@itemize @bullet
1386
@item libavcodec is the library containing the codecs (both encoding and
1387
decoding). Look at @file{libavcodec/apiexample.c} to see how to use it.
1388

    
1389
@item libavformat is the library containing the file format handling (mux and
1390
demux code for several formats). Look at @file{ffplay.c} to use it in a
1391
player. See @file{output_example.c} to use it to generate audio or video
1392
streams.
1393

    
1394
@end itemize
1395

    
1396
@section Integrating libavcodec or libavformat in your program
1397

    
1398
You can integrate all the source code of the libraries to link them
1399
statically to avoid any version problem. All you need is to provide a
1400
'config.mak' and a 'config.h' in the parent directory. See the defines
1401
generated by ./configure to understand what is needed.
1402

    
1403
You can use libavcodec or libavformat in your commercial program, but
1404
@emph{any patch you make must be published}. The best way to proceed is
1405
to send your patches to the FFmpeg mailing list.
1406

    
1407
@node Coding Rules
1408
@section Coding Rules
1409

    
1410
FFmpeg is programmed in the ISO C90 language with a few additional
1411
features from ISO C99, namely:
1412
@itemize @bullet
1413
@item
1414
the @samp{inline} keyword;
1415
@item
1416
@samp{//} comments;
1417
@item
1418
designated struct initializers (@samp{struct s x = @{ .i = 17 @};})
1419
@item
1420
compound literals (@samp{x = (struct s) @{ 17, 23 @};})
1421
@end itemize
1422

    
1423
These features are supported by all compilers we care about, so we will not
1424
accept patches to remove their use unless they absolutely do not impair
1425
clarity and performance.
1426

    
1427
All code must compile with GCC 2.95 and GCC 3.3. Currently, FFmpeg also
1428
compiles with several other compilers, such as the Compaq ccc compiler
1429
or Sun Studio 9, and we would like to keep it that way unless it would
1430
be exceedingly involved. To ensure compatibility, please do not use any
1431
additional C99 features or GCC extensions. Especially watch out for:
1432
@itemize @bullet
1433
@item
1434
mixing statements and declarations;
1435
@item
1436
@samp{long long} (use @samp{int64_t} instead);
1437
@item
1438
@samp{__attribute__} not protected by @samp{#ifdef __GNUC__} or similar;
1439
@item
1440
GCC statement expressions (@samp{(x = (@{ int y = 4; y; @})}).
1441
@end itemize
1442

    
1443
Indent size is 4.
1444
The presentation is the one specified by 'indent -i4 -kr -nut'.
1445
The TAB character is forbidden outside of Makefiles as is any
1446
form of trailing whitespace. Commits containing either will be
1447
rejected by the Subversion repository.
1448

    
1449
Main priority in FFmpeg is simplicity and small code size (=less
1450
bugs).
1451

    
1452
Comments: Use the JavaDoc/Doxygen
1453
format (see examples below) so that code documentation
1454
can be generated automatically. All nontrivial functions should have a comment
1455
above them explaining what the function does, even if it is just one sentence.
1456
All structures and their member variables should be documented, too.
1457
@example
1458
/**
1459
 * @@file mpeg.c
1460
 * MPEG codec.
1461
 * @@author ...
1462
 */
1463

    
1464
/**
1465
 * Summary sentence.
1466
 * more text ...
1467
 * ...
1468
 */
1469
typedef struct Foobar@{
1470
    int var1; /**< var1 description */
1471
    int var2; ///< var2 description
1472
    /** var3 description */
1473
    int var3;
1474
@} Foobar;
1475

    
1476
/**
1477
 * Summary sentence.
1478
 * more text ...
1479
 * ...
1480
 * @@param my_parameter description of my_parameter
1481
 * @@return return value description
1482
 */
1483
int myfunc(int my_parameter)
1484
...
1485
@end example
1486

    
1487
fprintf and printf are forbidden in libavformat and libavcodec,
1488
please use av_log() instead.
1489

    
1490
@section Development Policy
1491

    
1492
@enumerate
1493
@item
1494
   You must not commit code which breaks FFmpeg! (Meaning unfinished but
1495
   enabled code which breaks compilation or compiles but does not work or
1496
   breaks the regression tests)
1497
   You can commit unfinished stuff (for testing etc), but it must be disabled
1498
   (#ifdef etc) by default so it does not interfere with other developers'
1499
   work.
1500
@item
1501
   You do not have to over-test things. If it works for you, and you think it
1502
   should work for others, then commit. If your code has problems
1503
   (portability, triggers compiler bugs, unusual environment etc) they will be
1504
   reported and eventually fixed.
1505
@item
1506
   Do not commit unrelated changes together, split them into self-contained
1507
   pieces. Also do not forget that if part B depends on part A, but A does not
1508
   depend on B, then A can and should be committed first and separate from B.
1509
   Keeping changes well split into self-contained parts makes reviewing and
1510
   understanding them on the commit log mailing list easier. This also helps
1511
   in case of debugging later on.
1512
   Also if you have doubts about splitting or not splitting, do not hesitate to
1513
   ask/discuss it on the developer mailing list.
1514
@item
1515
   Do not change behavior of the program (renaming options etc) without
1516
   first discussing it on the ffmpeg-devel mailing list. Do not remove
1517
   functionality from the code. Just improve!
1518

    
1519
   Note: Redundant code can be removed.
1520
@item
1521
   Do not commit changes to the build system (Makefiles, configure script)
1522
   which change behavior, defaults etc, without asking first. The same
1523
   applies to compiler warning fixes, trivial looking fixes and to code
1524
   maintained by other developers. We usually have a reason for doing things
1525
   the way we do. Send your changes as patches to the ffmpeg-devel mailing
1526
   list, and if the code maintainers say OK, you may commit. This does not
1527
   apply to files you wrote and/or maintain.
1528
@item
1529
   We refuse source indentation and other cosmetic changes if they are mixed
1530
   with functional changes, such commits will be rejected and removed. Every
1531
   developer has his own indentation style, you should not change it. Of course
1532
   if you (re)write something, you can use your own style, even though we would
1533
   prefer if the indentation throughout FFmpeg was consistent (Many projects
1534
   force a given indentation style - we do not.). If you really need to make
1535
   indentation changes (try to avoid this), separate them strictly from real
1536
   changes.
1537

    
1538
   NOTE: If you had to put if()@{ .. @} over a large (> 5 lines) chunk of code,
1539
   then either do NOT change the indentation of the inner part within (do not
1540
   move it to the right)! or do so in a separate commit
1541
@item
1542
   Always fill out the commit log message. Describe in a few lines what you
1543
   changed and why. You can refer to mailing list postings if you fix a
1544
   particular bug. Comments such as "fixed!" or "Changed it." are unacceptable.
1545
@item
1546
   If you apply a patch by someone else, include the name and email address in
1547
   the log message. Since the ffmpeg-cvslog mailing list is publicly
1548
   archived you should add some SPAM protection to the email address. Send an
1549
   answer to ffmpeg-devel (or wherever you got the patch from) saying that
1550
   you applied the patch.
1551
@item
1552
   When applying patches that have been discussed (at length) on the mailing
1553
   list, reference the thread in the log message.
1554
@item
1555
    Do NOT commit to code actively maintained by others without permission.
1556
    Send a patch to ffmpeg-devel instead. If noone answers within a reasonable
1557
    timeframe (12h for build failures and security fixes, 3 days small changes,
1558
    1 week for big patches) then commit your patch if you think it is OK.
1559
    Also note, the maintainer can simply ask for more time to review!
1560
@item
1561
    Subscribe to the ffmpeg-cvslog mailing list. The diffs of all commits
1562
    are sent there and reviewed by all the other developers. Bugs and possible
1563
    improvements or general questions regarding commits are discussed there. We
1564
    expect you to react if problems with your code are uncovered.
1565
@item
1566
    Update the documentation if you change behavior or add features. If you are
1567
    unsure how best to do this, send a patch to ffmpeg-devel, the documentation
1568
    maintainer(s) will review and commit your stuff.
1569
@item
1570
    Try to keep important discussions and requests (also) on the public
1571
    developer mailing list, so that all developers can benefit from them.
1572
@item
1573
    Never write to unallocated memory, never write over the end of arrays,
1574
    always check values read from some untrusted source before using them
1575
    as array index or other risky things.
1576
@item
1577
    Remember to check if you need to bump versions for the specific libav
1578
    parts (libavutil, libavcodec, libavformat) you are changing. You need
1579
    to change the version integer and the version string.
1580
    Incrementing the first component means no backward compatibility to
1581
    previous versions (e.g. removal of a function from the public API).
1582
    Incrementing the second component means backward compatible change
1583
    (e.g. addition of a function to the public API).
1584
    Incrementing the third component means a noteworthy binary compatible
1585
    change (e.g. encoder bug fix that matters for the decoder).
1586
@item
1587
    If you add a new codec, remember to update the changelog, add it to
1588
    the supported codecs table in the documentation and bump the second
1589
    component of the @file{libavcodec} version number appropriately. If
1590
    it has a fourcc, add it to @file{libavformat/avienc.c}, even if it
1591
    is only a decoder.
1592
@item
1593
    Do not change code to hide warnings without ensuring that the underlying
1594
    logic is correct and thus the warning was inappropriate.
1595
@end enumerate
1596

    
1597
We think our rules are not too hard. If you have comments, contact us.
1598

    
1599
Note, these rules are mostly borrowed from the MPlayer project.
1600

    
1601
@section Submitting patches
1602

    
1603
First, (@pxref{Coding Rules}) above if you did not yet.
1604

    
1605
When you submit your patch, try to send a unified diff (diff '-up'
1606
option). I cannot read other diffs :-)
1607

    
1608
Also please do not submit patches which contain several unrelated changes.
1609
Split them into individual self-contained patches; this makes reviewing
1610
them much easier.
1611

    
1612
Run the regression tests before submitting a patch so that you can
1613
verify that there are no big problems.
1614

    
1615
Patches should be posted as base64 encoded attachments (or any other
1616
encoding which ensures that the patch will not be trashed during
1617
transmission) to the ffmpeg-devel mailing list, see
1618
@url{http://lists.mplayerhq.hu/mailman/listinfo/ffmpeg-devel}
1619

    
1620
It also helps quite a bit if you tell us what the patch does (for example
1621
'replaces lrint by lrintf'), and why (for example '*BSD isn't C99 compliant
1622
and has no lrint()')
1623

    
1624
Also please if you send several patches, send each patch as separate mail,
1625
do not attach several unrelated patches to the same mail.
1626

    
1627
@section patch submission checklist
1628

    
1629
@enumerate
1630
@item
1631
    Do the regression tests pass with the patch applied?
1632
@item
1633
    Is the patch a unified diff?
1634
@item
1635
    Is the patch against latest ffmpeg SVN?
1636
@item
1637
    Are you subscribed to ffmpeg-dev?
1638
    (the list is subscribers only due to spam)
1639
@item
1640
    Have you checked that the changes are minimal, so that the same cannot be
1641
    achieved with a smaller patch and/or simpler final code?
1642
@item
1643
    If the change is to speed critical code did you benchmark it?
1644
@item
1645
    Have you checked that the patch does not introduce buffer overflows or
1646
    other security issues?
1647
@item
1648
    Is the patch made from the root of the source, so it can be applied with -p0?
1649
@item
1650
    Does the patch not mix functional and cosmetic changes?
1651
@item
1652
    Is the patch attached to the email you send?
1653
@item
1654
    Is the mime type of the patch correct? (not application/octet-stream)
1655
@item
1656
    If the patch fixes a bug did you provide a verbose analysis of the bug?
1657
@item
1658
    If the patch fixes a bug did you provide enough information, including
1659
    a sample, so the bug can be reproduced and the fix can be verified?
1660
@item
1661
    Did you provide a verbose summary about what the patch does change?
1662
@item
1663
    Did you provide a verbose explanation why it changes things like it does?
1664
@item
1665
    Did you provide a verbose summary of the user visible advantages and
1666
    disadvantages if the patch is applied?
1667
@item
1668
    Did you provide an example so we can verify the new feature added by the
1669
    patch easily?
1670
@item
1671
    If you did any benchmarks, did you provide them in the mail?
1672
@end enumerate
1673

    
1674
@section Patch review process
1675

    
1676
All patches posted to ffmpeg-devel will be reviewed, unless they contain a
1677
clear note that the patch is not for SVN.
1678
Reviews and comments will be posted as replies to the patch on the
1679
mailing list. The patch submitter then has to take care of every comment,
1680
that can be by resubmitting a changed patch or by discussion. Resubmitted
1681
patches will themselves be reviewed like any other patch. If at some point
1682
a patch passes review with no comments then it is approved, that can for
1683
simple and small patches happen immediately while large patches will generally
1684
have to be changed and reviewed many times before they are approved.
1685
After a patch is approved it will be committed to the repository.
1686

    
1687
We will review all submitted patches, but sometimes we are quite busy so
1688
especially for large patches this can take several weeks.
1689

    
1690
When resubmitting patches, please do not make any significant changes
1691
not related to the comments received during review. Such patches will
1692
be rejected. Instead, submit  significant changes or new features as
1693
separate patches.
1694

    
1695
@section Regression tests
1696

    
1697
Before submitting a patch (or committing to the repository), you should at least
1698
test that you did not break anything.
1699

    
1700
The regression tests build a synthetic video stream and a synthetic
1701
audio stream. These are then encoded and decoded with all codecs or
1702
formats. The CRC (or MD5) of each generated file is recorded in a
1703
result file. A 'diff' is launched to compare the reference results and
1704
the result file.
1705

    
1706
The regression tests then go on to test the FFserver code with a
1707
limited set of streams. It is important that this step runs correctly
1708
as well.
1709

    
1710
Run 'make test' to test all the codecs and formats.
1711

    
1712
Run 'make fulltest' to test all the codecs, formats and FFserver.
1713

    
1714
[Of course, some patches may change the results of the regression tests. In
1715
this case, the reference results of the regression tests shall be modified
1716
accordingly].
1717

    
1718
@bye