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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 -s cif -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 -s cif -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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@item qqvga
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160x120
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@item qvga
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320x240
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@item vga
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640x480
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@item svga
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800x600
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@item xga
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1024x768
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@item uxga
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1600x1200
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@item qxga
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2048x1536
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@item sxga
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1280x1024
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@item qsxga
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2560x2048
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@item hsxga
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5120x4096
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@item wvga
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852x480
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@item wxga
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1366x768
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@item wsxga
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1600x1024
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@item wuxga
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1920x1200
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@item woxga
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2560x1600
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@item wqsxga
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3200x2048
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@item wquxga
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3840x2400
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@item whsxga
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6400x4096
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@item whuxga
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7680x4800
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@item cga
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320x200
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@item ega
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640x350
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@item hd480
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852x480
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@item hd720
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1280x720
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@item hd1080
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1920x1080
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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 -vstats_file file
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Dump video coding statistics to @var{file}.
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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.
677
@item -debug
678
Print specific debug info.
679
@item -benchmark
680
Add timings for benchmarking.
681
@item -dump
682
Dump each input packet.
683
@item -hex
684
When dumping packets, also dump the payload.
685
@item -bitexact
686
Only use bit exact algorithms (for codec testing).
687
@item -ps size
688
Set packet size in bits.
689
@item -re
690
Read input at native frame rate. Mainly used to simulate a grab device.
691
@item -loop_input
692
Loop over the input stream. Currently it works only for image
693
streams. This option is used for automatic FFserver testing.
694
@item -loop_output number_of_times
695
Repeatedly loop output for formats that support looping such as animated GIF
696
(0 will loop the output infinitely).
697
@item -threads count
698
Thread count.
699
@item -vsync parameter
700
Video sync method. Video will be stretched/squeezed to match the timestamps,
701
it is done by duplicating and dropping frames. With -map you can select from
702
which stream the timestamps should be taken. You can leave either video or
703
audio unchanged and sync the remaining stream(s) to the unchanged one.
704
@item -async samples_per_second
705
Audio sync method. "Stretches/squeezes" the audio stream to match the timestamps,
706
the parameter is the maximum samples per second by which the audio is changed.
707
-async 1 is a special case where only the start of the audio stream is corrected
708
without any later correction.
709
@end table
710

    
711
@node FFmpeg formula evaluator
712
@section FFmpeg formula evaluator
713

    
714
When evaluating a rate control string, FFmpeg uses an internal formula
715
evaluator.
716

    
717
The following binary operators are available: @code{+}, @code{-},
718
@code{*}, @code{/}, @code{^}.
719

    
720
The following unary operators are available: @code{+}, @code{-},
721
@code{(...)}.
722

    
723
The following functions are available:
724
@table @var
725
@item sinh(x)
726
@item cosh(x)
727
@item tanh(x)
728
@item sin(x)
729
@item cos(x)
730
@item tan(x)
731
@item exp(x)
732
@item log(x)
733
@item squish(x)
734
@item gauss(x)
735
@item abs(x)
736
@item max(x, y)
737
@item min(x, y)
738
@item gt(x, y)
739
@item lt(x, y)
740
@item eq(x, y)
741
@item bits2qp(bits)
742
@item qp2bits(qp)
743
@end table
744

    
745
The following constants are available:
746
@table @var
747
@item PI
748
@item E
749
@item iTex
750
@item pTex
751
@item tex
752
@item mv
753
@item fCode
754
@item iCount
755
@item mcVar
756
@item var
757
@item isI
758
@item isP
759
@item isB
760
@item avgQP
761
@item qComp
762
@item avgIITex
763
@item avgPITex
764
@item avgPPTex
765
@item avgBPTex
766
@item avgTex
767
@end table
768

    
769
@c man end
770

    
771
@ignore
772

    
773
@setfilename ffmpeg
774
@settitle FFmpeg video converter
775

    
776
@c man begin SEEALSO
777
ffserver(1), ffplay(1) and the HTML documentation of @file{ffmpeg}.
778
@c man end
779

    
780
@c man begin AUTHOR
781
Fabrice Bellard
782
@c man end
783

    
784
@end ignore
785

    
786
@section Protocols
787

    
788
The filename can be @file{-} to read from standard input or to write
789
to standard output.
790

    
791
FFmpeg also handles many protocols specified with an URL syntax.
792

    
793
Use 'ffmpeg -formats' to see a list of the supported protocols.
794

    
795
The protocol @code{http:} is currently used only to communicate with
796
FFserver (see the FFserver documentation). When FFmpeg will be a
797
video player it will also be used for streaming :-)
798

    
799
@chapter Tips
800

    
801
@itemize
802
@item For streaming at very low bitrate application, use a low frame rate
803
and a small GOP size. This is especially true for RealVideo where
804
the Linux player does not seem to be very fast, so it can miss
805
frames. An example is:
806

    
807
@example
808
ffmpeg -g 3 -r 3 -t 10 -b 50k -s qcif -f rv10 /tmp/b.rm
809
@end example
810

    
811
@item  The parameter 'q' which is displayed while encoding is the current
812
quantizer. The value 1 indicates that a very good quality could
813
be achieved. The value 31 indicates the worst quality. If q=31 appears
814
too often, it means that the encoder cannot compress enough to meet
815
your bitrate. You must either increase the bitrate, decrease the
816
frame rate or decrease the frame size.
817

    
818
@item If your computer is not fast enough, you can speed up the
819
compression at the expense of the compression ratio. You can use
820
'-me zero' to speed up motion estimation, and '-intra' to disable
821
motion estimation completely (you have only I-frames, which means it
822
is about as good as JPEG compression).
823

    
824
@item To have very low audio bitrates, reduce the sampling frequency
825
(down to 22050 kHz for MPEG audio, 22050 or 11025 for AC3).
826

    
827
@item To have a constant quality (but a variable bitrate), use the option
828
'-qscale n' when 'n' is between 1 (excellent quality) and 31 (worst
829
quality).
830

    
831
@item When converting video files, you can use the '-sameq' option which
832
uses the same quality factor in the encoder as in the decoder.
833
It allows almost lossless encoding.
834

    
835
@end itemize
836

    
837

    
838
@chapter external libraries
839

    
840
FFmpeg can be hooked up with a number of external libraries to add support
841
for more formats. None of them are used by default, their use has to be
842
explicitly requested by passing the appropriate flags to @file{./configure}.
843

    
844
@section AMR
845

    
846
AMR comes in two different flavors, WB and NB. FFmpeg can make use of the
847
AMR WB (floating-point mode) and the AMR NB (floating-point mode) reference
848
decoders and encoders.
849

    
850
Go to @url{http://www.penguin.cz/~utx/amr} and follow the instructions for
851
installing the libraries. Then pass @code{--enable-amr-nb} and/or
852
@code{--enable-amr-wb} to configure to enable the libraries.
853

    
854

    
855
@chapter Supported File Formats and Codecs
856

    
857
You can use the @code{-formats} option to have an exhaustive list.
858

    
859
@section File Formats
860

    
861
FFmpeg supports the following file formats through the @code{libavformat}
862
library:
863

    
864
@multitable @columnfractions .4 .1 .1 .4
865
@item Supported File Format @tab Encoding @tab Decoding @tab Comments
866
@item MPEG audio @tab X @tab X
867
@item MPEG-1 systems @tab X  @tab  X
868
@tab muxed audio and video
869
@item MPEG-2 PS @tab X  @tab  X
870
@tab also known as @code{VOB} file
871
@item MPEG-2 TS @tab    @tab  X
872
@tab also known as DVB Transport Stream
873
@item ASF@tab X @tab X
874
@item AVI@tab X @tab X
875
@item WAV@tab X @tab X
876
@item Macromedia Flash@tab X @tab X
877
@tab Only embedded audio is decoded.
878
@item FLV              @tab  X @tab X
879
@tab Macromedia Flash video files
880
@item Real Audio and Video @tab X @tab X
881
@item Raw AC3 @tab X  @tab  X
882
@item Raw MJPEG @tab X  @tab  X
883
@item Raw MPEG video @tab X  @tab  X
884
@item Raw PCM8/16 bits, mulaw/Alaw@tab X  @tab  X
885
@item Raw CRI ADX audio @tab X  @tab  X
886
@item Raw Shorten audio @tab    @tab  X
887
@item SUN AU format @tab X  @tab  X
888
@item NUT @tab X @tab X @tab NUT Open Container Format
889
@item QuickTime        @tab X @tab  X
890
@item MPEG-4           @tab X @tab  X
891
@tab MPEG-4 is a variant of QuickTime.
892
@item Raw MPEG4 video  @tab  X @tab  X
893
@item DV               @tab  X @tab  X
894
@item 4xm              @tab    @tab X
895
@tab 4X Technologies format, used in some games.
896
@item Playstation STR  @tab    @tab X
897
@item Id RoQ           @tab    @tab X
898
@tab Used in Quake III, Jedi Knight 2, other computer games.
899
@item Interplay MVE    @tab    @tab X
900
@tab Format used in various Interplay computer games.
901
@item WC3 Movie        @tab    @tab X
902
@tab Multimedia format used in Origin's Wing Commander III computer game.
903
@item Sega FILM/CPK    @tab    @tab X
904
@tab Used in many Sega Saturn console games.
905
@item Westwood Studios VQA/AUD  @tab    @tab X
906
@tab Multimedia formats used in Westwood Studios games.
907
@item Id Cinematic (.cin) @tab    @tab X
908
@tab Used in Quake II.
909
@item FLIC format      @tab    @tab X
910
@tab .fli/.flc files
911
@item Sierra VMD       @tab    @tab X
912
@tab Used in Sierra CD-ROM games.
913
@item Sierra Online    @tab    @tab X
914
@tab .sol files used in Sierra Online games.
915
@item Matroska         @tab    @tab X
916
@item Electronic Arts Multimedia    @tab    @tab X
917
@tab Used in various EA games; files have extensions like WVE and UV2.
918
@item Nullsoft Video (NSV) format @tab    @tab X
919
@item ADTS AAC audio @tab X @tab X
920
@item Creative VOC @tab X @tab X @tab Created for the Sound Blaster Pro.
921
@item American Laser Games MM  @tab    @tab X
922
@tab Multimedia format used in games like Mad Dog McCree
923
@item AVS @tab    @tab X
924
@tab Multimedia format used by the Creature Shock game.
925
@item Smacker @tab    @tab X
926
@tab Multimedia format used by many games.
927
@item GXF @tab  X @tab X
928
@tab General eXchange Format SMPTE 360M, used by Thomson Grass Valley playout servers.
929
@item CIN @tab    @tab X
930
@tab Multimedia format used by Delphine Software games.
931
@item MXF @tab    @tab X
932
@tab Material eXchange Format SMPTE 377M, used by D-Cinema, broadcast industry.
933
@item SEQ @tab    @tab X
934
@tab Tiertex .seq files used in the DOS CDROM version of the game Flashback.
935
@item DXA @tab    @tab X
936
@tab This format is used in non-Windows version of Feeble Files game and
937
different game cutscenes repacked for use with ScummVM.
938
@item THP @tab    @tab X
939
@tab Used on the Nintendo GameCube.
940
@item C93 @tab    @tab X
941
@tab Used in the game Cyberia from Interplay.
942
@item Bethsoft VID @tab    @tab X
943
@tab Used in some games from Bethesda Softworks.
944
@item CRYO APC @tab    @tab X
945
@tab Audio format used in some games by CRYO Interactive Entertainment.
946
@end multitable
947

    
948
@code{X} means that encoding (resp. decoding) is supported.
949

    
950
@section Image Formats
951

    
952
FFmpeg can read and write images for each frame of a video sequence. The
953
following image formats are supported:
954

    
955
@multitable @columnfractions .4 .1 .1 .4
956
@item Supported Image Format @tab Encoding @tab Decoding @tab Comments
957
@item PGM, PPM     @tab X @tab X
958
@item PAM          @tab X @tab X @tab PAM is a PNM extension with alpha support.
959
@item PGMYUV       @tab X @tab X @tab PGM with U and V components in YUV 4:2:0
960
@item JPEG         @tab X @tab X @tab Progressive JPEG is not supported.
961
@item .Y.U.V       @tab X @tab X @tab one raw file per component
962
@item animated GIF @tab X @tab X @tab Only uncompressed GIFs are generated.
963
@item PNG          @tab X @tab X @tab 2 bit and 4 bit/pixel not supported yet.
964
@item Targa        @tab   @tab X @tab Targa (.TGA) image format.
965
@item TIFF         @tab X @tab X @tab YUV, JPEG and some extension is not supported yet.
966
@item SGI          @tab X @tab X @tab SGI RGB image format
967
@end multitable
968

    
969
@code{X} means that encoding (resp. decoding) is supported.
970

    
971
@section Video Codecs
972

    
973
@multitable @columnfractions .4 .1 .1 .4
974
@item Supported Codec @tab Encoding @tab Decoding @tab Comments
975
@item MPEG-1 video           @tab  X  @tab  X
976
@item MPEG-2 video           @tab  X  @tab  X
977
@item MPEG-4                 @tab  X  @tab  X
978
@item MSMPEG4 V1             @tab  X  @tab  X
979
@item MSMPEG4 V2             @tab  X  @tab  X
980
@item MSMPEG4 V3             @tab  X  @tab  X
981
@item WMV7                   @tab  X  @tab  X
982
@item WMV8                   @tab  X  @tab  X @tab not completely working
983
@item WMV9                   @tab     @tab  X @tab not completely working
984
@item VC1                    @tab     @tab  X
985
@item H.261                  @tab  X  @tab  X
986
@item H.263(+)               @tab  X  @tab  X @tab also known as RealVideo 1.0
987
@item H.264                  @tab     @tab  X
988
@item RealVideo 1.0          @tab  X  @tab  X
989
@item RealVideo 2.0          @tab  X  @tab  X
990
@item MJPEG                  @tab  X  @tab  X
991
@item lossless MJPEG         @tab  X  @tab  X
992
@item JPEG-LS                @tab  X  @tab  X @tab fourcc: MJLS, lossless and near-lossless is supported
993
@item Apple MJPEG-B          @tab     @tab  X
994
@item Sunplus MJPEG          @tab     @tab  X @tab fourcc: SP5X
995
@item DV                     @tab  X  @tab  X
996
@item HuffYUV                @tab  X  @tab  X
997
@item FFmpeg Video 1         @tab  X  @tab  X @tab experimental lossless codec (fourcc: FFV1)
998
@item FFmpeg Snow            @tab  X  @tab  X @tab experimental wavelet codec (fourcc: SNOW)
999
@item Asus v1                @tab  X  @tab  X @tab fourcc: ASV1
1000
@item Asus v2                @tab  X  @tab  X @tab fourcc: ASV2
1001
@item Creative YUV           @tab     @tab  X @tab fourcc: CYUV
1002
@item Sorenson Video 1       @tab  X  @tab  X @tab fourcc: SVQ1
1003
@item Sorenson Video 3       @tab     @tab  X @tab fourcc: SVQ3
1004
@item On2 VP3                @tab     @tab  X @tab still experimental
1005
@item On2 VP5                @tab     @tab  X @tab fourcc: VP50
1006
@item On2 VP6                @tab     @tab  X @tab fourcc: VP60,VP61,VP62
1007
@item Theora                 @tab  X  @tab  X @tab still experimental
1008
@item Intel Indeo 3          @tab     @tab  X
1009
@item FLV                    @tab  X  @tab  X @tab Sorenson H.263 used in Flash
1010
@item Flash Screen Video     @tab  X  @tab  X @tab fourcc: FSV1
1011
@item ATI VCR1               @tab     @tab  X @tab fourcc: VCR1
1012
@item ATI VCR2               @tab     @tab  X @tab fourcc: VCR2
1013
@item Cirrus Logic AccuPak   @tab     @tab  X @tab fourcc: CLJR
1014
@item 4X Video               @tab     @tab  X @tab Used in certain computer games.
1015
@item Sony Playstation MDEC  @tab     @tab  X
1016
@item Id RoQ                 @tab     @tab  X @tab Used in Quake III, Jedi Knight 2, other computer games.
1017
@item Xan/WC3                @tab     @tab  X @tab Used in Wing Commander III .MVE files.
1018
@item Interplay Video        @tab     @tab  X @tab Used in Interplay .MVE files.
1019
@item Apple Animation        @tab     @tab  X @tab fourcc: 'rle '
1020
@item Apple Graphics         @tab     @tab  X @tab fourcc: 'smc '
1021
@item Apple Video            @tab     @tab  X @tab fourcc: rpza
1022
@item Apple QuickDraw        @tab     @tab  X @tab fourcc: qdrw
1023
@item Cinepak                @tab     @tab  X
1024
@item Microsoft RLE          @tab     @tab  X
1025
@item Microsoft Video-1      @tab     @tab  X
1026
@item Westwood VQA           @tab     @tab  X
1027
@item Id Cinematic Video     @tab     @tab  X @tab Used in Quake II.
1028
@item Planar RGB             @tab     @tab  X @tab fourcc: 8BPS
1029
@item FLIC video             @tab     @tab  X
1030
@item Duck TrueMotion v1     @tab     @tab  X @tab fourcc: DUCK
1031
@item Duck TrueMotion v2     @tab     @tab  X @tab fourcc: TM20
1032
@item VMD Video              @tab     @tab  X @tab Used in Sierra VMD files.
1033
@item MSZH                   @tab     @tab  X @tab Part of LCL
1034
@item ZLIB                   @tab  X  @tab  X @tab Part of LCL, encoder experimental
1035
@item TechSmith Camtasia     @tab     @tab  X @tab fourcc: TSCC
1036
@item IBM Ultimotion         @tab     @tab  X @tab fourcc: ULTI
1037
@item Miro VideoXL           @tab     @tab  X @tab fourcc: VIXL
1038
@item QPEG                   @tab     @tab  X @tab fourccs: QPEG, Q1.0, Q1.1
1039
@item LOCO                   @tab     @tab  X @tab
1040
@item Winnov WNV1            @tab     @tab  X @tab
1041
@item Autodesk Animator Studio Codec  @tab     @tab  X @tab fourcc: AASC
1042
@item Fraps FPS1             @tab     @tab  X @tab
1043
@item CamStudio              @tab     @tab  X @tab fourcc: CSCD
1044
@item American Laser Games Video  @tab    @tab X @tab Used in games like Mad Dog McCree
1045
@item ZMBV                   @tab   X @tab  X @tab Encoder works only on PAL8
1046
@item AVS Video              @tab     @tab  X @tab Video encoding used by the Creature Shock game.
1047
@item Smacker Video          @tab     @tab  X @tab Video encoding used in Smacker.
1048
@item RTjpeg                 @tab     @tab  X @tab Video encoding used in NuppelVideo files.
1049
@item KMVC                   @tab     @tab  X @tab Codec used in Worms games.
1050
@item VMware Video           @tab     @tab  X @tab Codec used in videos captured by VMware.
1051
@item Cin Video              @tab     @tab  X @tab Codec used in Delphine Software games.
1052
@item Tiertex Seq Video      @tab     @tab  X @tab Codec used in DOS CDROM FlashBack game.
1053
@item DXA Video              @tab     @tab  X @tab Codec originally used in Feeble Files game.
1054
@item AVID DNxHD             @tab     @tab  X @tab aka SMPTE VC3
1055
@item C93 Video              @tab     @tab  X @tab Codec used in Cyberia game.
1056
@item THP                    @tab     @tab  X @tab Used on the Nintendo GameCube.
1057
@item Bethsoft VID           @tab     @tab  X @tab Used in some games from Bethesda Softworks.
1058
@end multitable
1059

    
1060
@code{X} means that encoding (resp. decoding) is supported.
1061

    
1062
@section Audio Codecs
1063

    
1064
@multitable @columnfractions .4 .1 .1 .1 .7
1065
@item Supported Codec @tab Encoding @tab Decoding @tab Comments
1066
@item MPEG audio layer 2     @tab  IX  @tab  IX
1067
@item MPEG audio layer 1/3   @tab IX   @tab  IX
1068
@tab MP3 encoding is supported through the external library LAME.
1069
@item AC3                    @tab  IX  @tab  IX
1070
@tab liba52 is used internally for decoding.
1071
@item Vorbis                 @tab  X   @tab  X
1072
@item WMA V1/V2              @tab X    @tab X
1073
@item AAC                    @tab X    @tab X
1074
@tab Supported through the external library libfaac/libfaad.
1075
@item Microsoft ADPCM        @tab X    @tab X
1076
@item MS IMA ADPCM           @tab X    @tab X
1077
@item QT IMA ADPCM           @tab      @tab X
1078
@item 4X IMA ADPCM           @tab      @tab X
1079
@item G.726  ADPCM           @tab X    @tab X
1080
@item Duck DK3 IMA ADPCM     @tab      @tab X
1081
@tab Used in some Sega Saturn console games.
1082
@item Duck DK4 IMA ADPCM     @tab      @tab X
1083
@tab Used in some Sega Saturn console games.
1084
@item Westwood Studios IMA ADPCM @tab      @tab X
1085
@tab Used in Westwood Studios games like Command and Conquer.
1086
@item SMJPEG IMA ADPCM       @tab      @tab X
1087
@tab Used in certain Loki game ports.
1088
@item CD-ROM XA ADPCM        @tab      @tab X
1089
@item CRI ADX ADPCM          @tab X    @tab X
1090
@tab Used in Sega Dreamcast games.
1091
@item Electronic Arts ADPCM  @tab      @tab X
1092
@tab Used in various EA titles.
1093
@item Creative ADPCM         @tab      @tab X
1094
@tab 16 -> 4, 8 -> 4, 8 -> 3, 8 -> 2
1095
@item THP ADPCM              @tab      @tab X
1096
@tab Used on the Nintendo GameCube.
1097
@item RA144                  @tab      @tab X
1098
@tab Real 14400 bit/s codec
1099
@item RA288                  @tab      @tab X
1100
@tab Real 28800 bit/s codec
1101
@item RADnet                 @tab X    @tab IX
1102
@tab Real low bitrate AC3 codec, liba52 is used for decoding.
1103
@item AMR-NB                 @tab X    @tab X
1104
@tab Supported through an external library.
1105
@item AMR-WB                 @tab X    @tab X
1106
@tab Supported through an external library.
1107
@item DV audio               @tab      @tab X
1108
@item Id RoQ DPCM            @tab      @tab X
1109
@tab Used in Quake III, Jedi Knight 2, other computer games.
1110
@item Interplay MVE DPCM     @tab      @tab X
1111
@tab Used in various Interplay computer games.
1112
@item Xan DPCM               @tab      @tab X
1113
@tab Used in Origin's Wing Commander IV AVI files.
1114
@item Sierra Online DPCM     @tab      @tab X
1115
@tab Used in Sierra Online game audio files.
1116
@item Apple MACE 3           @tab      @tab X
1117
@item Apple MACE 6           @tab      @tab X
1118
@item FLAC lossless audio    @tab X    @tab X
1119
@item Shorten lossless audio @tab      @tab X
1120
@item Apple lossless audio   @tab      @tab X
1121
@tab QuickTime fourcc 'alac'
1122
@item FFmpeg Sonic           @tab X    @tab X
1123
@tab experimental lossy/lossless codec
1124
@item Qdesign QDM2           @tab      @tab X
1125
@tab there are still some distortions
1126
@item Real COOK              @tab      @tab X
1127
@tab All versions except 5.1 are supported
1128
@item DSP Group TrueSpeech   @tab      @tab X
1129
@item True Audio (TTA)       @tab      @tab X
1130
@item Smacker Audio          @tab      @tab X
1131
@item WavPack Audio          @tab      @tab X
1132
@item Cin Audio              @tab      @tab X
1133
@tab Codec used in Delphine Software games.
1134
@item Intel Music Coder      @tab      @tab X
1135
@item Musepack               @tab      @tab X
1136
@tab Only SV7 is supported
1137
@item DT$ Coherent Audio     @tab      @tab X
1138
@item ATRAC 3                @tab      @tab X
1139
@end multitable
1140

    
1141
@code{X} means that encoding (resp. decoding) is supported.
1142

    
1143
@code{I} means that an integer-only version is available, too (ensures high
1144
performance on systems without hardware floating point support).
1145

    
1146
@chapter Platform Specific information
1147

    
1148
@section BSD
1149

    
1150
BSD make will not build FFmpeg, you need to install and use GNU Make
1151
(@file{gmake}).
1152

    
1153
@section Windows
1154

    
1155
To get help and instructions for using FFmpeg under Windows, check out
1156
the FFmpeg Windows Help Forum at
1157
@url{http://arrozcru.no-ip.org/ffmpeg/}.
1158

    
1159
@subsection Native Windows compilation
1160

    
1161
@itemize
1162
@item Install the current versions of MSYS and MinGW from
1163
@url{http://www.mingw.org/}. You can find detailed installation
1164
instructions in the download section and the FAQ.
1165

    
1166
NOTE: Use at least bash 3.1. Older versions are known to be failing on the
1167
configure script.
1168

    
1169
@item If you want to test the FFplay, also download
1170
the MinGW development library of SDL 1.2.x
1171
(@file{SDL-devel-1.2.x-mingw32.tar.gz}) from
1172
@url{http://www.libsdl.org}. Unpack it in a temporary directory, and
1173
unpack the archive @file{i386-mingw32msvc.tar.gz} in the MinGW tool
1174
directory. Edit the @file{sdl-config} script so that it gives the
1175
correct SDL directory when invoked.
1176

    
1177
@item Extract the current version of FFmpeg.
1178

    
1179
@item Start the MSYS shell (file @file{msys.bat}).
1180

    
1181
@item Change to the FFmpeg directory and follow
1182
 the instructions of how to compile FFmpeg (file
1183
@file{INSTALL}). Usually, launching @file{./configure} and @file{make}
1184
suffices. If you have problems using SDL, verify that
1185
@file{sdl-config} can be launched from the MSYS command line.
1186

    
1187
@item You can install FFmpeg in @file{Program Files/FFmpeg} by typing
1188
@file{make install}. Do not forget to copy @file{SDL.dll} to the place
1189
you launch @file{ffplay} from.
1190

    
1191
@end itemize
1192

    
1193
Notes:
1194
@itemize
1195

    
1196
@item The target @file{make wininstaller} can be used to create a
1197
Nullsoft based Windows installer for FFmpeg and FFplay. @file{SDL.dll}
1198
must be copied to the FFmpeg directory in order to build the
1199
installer.
1200

    
1201
@item By using @code{./configure --enable-shared} when configuring FFmpeg,
1202
you can build @file{avcodec.dll} and @file{avformat.dll}. With
1203
@code{make install} you install the FFmpeg DLLs and the associated
1204
headers in @file{Program Files/FFmpeg}.
1205

    
1206
@item Visual C++ compatibility: If you used @code{./configure --enable-shared}
1207
when configuring FFmpeg, FFmpeg tries to use the Microsoft Visual
1208
C++ @code{lib} tool to build @code{avcodec.lib} and
1209
@code{avformat.lib}. With these libraries you can link your Visual C++
1210
code directly with the FFmpeg DLLs (see below).
1211

    
1212
@end itemize
1213

    
1214
@subsection Visual C++ compatibility
1215

    
1216
FFmpeg will not compile under Visual C++ -- and it has too many
1217
dependencies on the GCC compiler to make a port viable. However,
1218
if you want to use the FFmpeg libraries in your own applications,
1219
you can still compile those applications using Visual C++. An
1220
important restriction to this is that you have to use the
1221
dynamically linked versions of the FFmpeg libraries (i.e. the
1222
DLLs), and you have to make sure that Visual-C++-compatible
1223
import libraries are created during the FFmpeg build process.
1224

    
1225
This description of how to use the FFmpeg libraries with Visual C++ is
1226
based on Visual C++ 2005 Express Edition Beta 2. If you have a different
1227
version, you might have to modify the procedures slightly.
1228

    
1229
Here are the step-by-step instructions for building the FFmpeg libraries
1230
so they can be used with Visual C++:
1231

    
1232
@enumerate
1233

    
1234
@item Install Visual C++ (if you have not done so already).
1235

    
1236
@item Install MinGW and MSYS as described above.
1237

    
1238
@item Add a call to @file{vcvars32.bat} (which sets up the environment
1239
variables for the Visual C++ tools) as the first line of
1240
@file{msys.bat}. The standard location for @file{vcvars32.bat} is
1241
@file{C:\Program Files\Microsoft Visual Studio 8\VC\bin\vcvars32.bat},
1242
and the standard location for @file{msys.bat} is
1243
@file{C:\msys\1.0\msys.bat}. If this corresponds to your setup, add the
1244
following line as the first line of @file{msys.bat}:
1245

    
1246
@code{call "C:\Program Files\Microsoft Visual Studio 8\VC\bin\vcvars32.bat"}
1247

    
1248
@item Start the MSYS shell (file @file{msys.bat}) and type @code{link.exe}.
1249
If you get a help message with the command line options of @code{link.exe},
1250
this means your environment variables are set up correctly, the
1251
Microsoft linker is on the path and will be used by FFmpeg to
1252
create Visual-C++-compatible import libraries.
1253

    
1254
@item Extract the current version of FFmpeg and change to the FFmpeg directory.
1255

    
1256
@item Type the command
1257
@code{./configure --enable-shared --disable-static --enable-memalign-hack}
1258
to configure and, if that did not produce any errors,
1259
type @code{make} to build FFmpeg.
1260

    
1261
@item The subdirectories @file{libavformat}, @file{libavcodec}, and
1262
@file{libavutil} should now contain the files @file{avformat.dll},
1263
@file{avformat.lib}, @file{avcodec.dll}, @file{avcodec.lib},
1264
@file{avutil.dll}, and @file{avutil.lib}, respectively. Copy the three
1265
DLLs to your System32 directory (typically @file{C:\Windows\System32}).
1266

    
1267
@end enumerate
1268

    
1269
And here is how to use these libraries with Visual C++:
1270

    
1271
@enumerate
1272

    
1273
@item Create a new console application ("File / New / Project") and then
1274
select "Win32 Console Application". On the appropriate page of the
1275
Application Wizard, uncheck the "Precompiled headers" option.
1276

    
1277
@item Write the source code for your application, or, for testing, just
1278
copy the code from an existing sample application into the source file
1279
that Visual C++ has already created for you. (Note that your source
1280
filehas to have a @code{.cpp} extension; otherwise, Visual C++ will not
1281
compile the FFmpeg headers correctly because in C mode, it does not
1282
recognize the @code{inline} keyword.)  For example, you can copy
1283
@file{output_example.c} from the FFmpeg distribution (but you will
1284
have to make minor modifications so the code will compile under
1285
C++, see below).
1286

    
1287
@item Open the "Project / Properties" dialog box. In the "Configuration"
1288
combo box, select "All Configurations" so that the changes you make will
1289
affect both debug and release builds. In the tree view on the left hand
1290
side, select "C/C++ / General", then edit the "Additional Include
1291
Directories" setting to contain the complete paths to the
1292
@file{libavformat}, @file{libavcodec}, and @file{libavutil}
1293
subdirectories of your FFmpeg directory. Note that the directories have
1294
to be separated using semicolons. Now select "Linker / General" from the
1295
tree view and edit the "Additional Library Directories" setting to
1296
contain the same three directories.
1297

    
1298
@item Still in the "Project / Properties" dialog box, select "Linker / Input"
1299
from the tree view, then add the files @file{avformat.lib},
1300
@file{avcodec.lib}, and @file{avutil.lib} to the end of the "Additional
1301
Dependencies". Note that the names of the libraries have to be separated
1302
using spaces.
1303

    
1304
@item Now, select "C/C++ / Code Generation" from the tree view. Select
1305
"Debug" in the "Configuration" combo box. Make sure that "Runtime
1306
Library" is set to "Multi-threaded Debug DLL". Then, select "Release" in
1307
the "Configuration" combo box and make sure that "Runtime Library" is
1308
set to "Multi-threaded DLL".
1309

    
1310
@item Click "OK" to close the "Project / Properties" dialog box and build
1311
the application. Hopefully, it should compile and run cleanly. If you
1312
used @file{output_example.c} as your sample application, you will get a
1313
few compiler errors, but they are easy to fix. The first type of error
1314
occurs because Visual C++ does not allow an @code{int} to be converted to
1315
an @code{enum} without a cast. To solve the problem, insert the required
1316
casts (this error occurs once for a @code{CodecID} and once for a
1317
@code{CodecType}).  The second type of error occurs because C++ requires
1318
the return value of @code{malloc} to be cast to the exact type of the
1319
pointer it is being assigned to. Visual C++ will complain that, for
1320
example, @code{(void *)} is being assigned to @code{(uint8_t *)} without
1321
an explicit cast. So insert an explicit cast in these places to silence
1322
the compiler. The third type of error occurs because the @code{snprintf}
1323
library function is called @code{_snprintf} under Visual C++.  So just
1324
add an underscore to fix the problem. With these changes,
1325
@file{output_example.c} should compile under Visual C++, and the
1326
resulting executable should produce valid video files.
1327

    
1328
@end enumerate
1329

    
1330
@subsection Cross compilation for Windows with Linux
1331

    
1332
You must use the MinGW cross compilation tools available at
1333
@url{http://www.mingw.org/}.
1334

    
1335
Then configure FFmpeg with the following options:
1336
@example
1337
./configure --target-os=mingw32 --cross-prefix=i386-mingw32msvc-
1338
@end example
1339
(you can change the cross-prefix according to the prefix chosen for the
1340
MinGW tools).
1341

    
1342
Then you can easily test FFmpeg with Wine
1343
(@url{http://www.winehq.com/}).
1344

    
1345
@subsection Compilation under Cygwin
1346

    
1347
Cygwin works very much like Unix.
1348

    
1349
Just install your Cygwin with all the "Base" packages, plus the
1350
following "Devel" ones:
1351
@example
1352
binutils, gcc-core, make, subversion
1353
@end example
1354

    
1355
Do not install binutils-20060709-1 (they are buggy on shared builds);
1356
use binutils-20050610-1 instead.
1357

    
1358
Then run
1359

    
1360
@example
1361
./configure --enable-static --disable-shared
1362
@end example
1363

    
1364
to make a static build or
1365

    
1366
@example
1367
./configure --enable-shared --disable-static
1368
@end example
1369

    
1370
to build shared libraries.
1371

    
1372
If you want to build FFmpeg with additional libraries, download Cygwin
1373
"Devel" packages for Ogg and Vorbis from any Cygwin packages repository
1374
and/or SDL, xvid, faac, faad2 packages from Cygwin Ports,
1375
(@url{http://cygwinports.dotsrc.org/}).
1376

    
1377
@subsection Crosscompilation for Windows under Cygwin
1378

    
1379
With Cygwin you can create Windows binaries that do not need the cygwin1.dll.
1380

    
1381
Just install your Cygwin as explained before, plus these additional
1382
"Devel" packages:
1383
@example
1384
gcc-mingw-core, mingw-runtime, mingw-zlib
1385
@end example
1386

    
1387
and add some special flags to your configure invocation.
1388

    
1389
For a static build run
1390
@example
1391
./configure --target-os=mingw32 --enable-memalign-hack --enable-static --disable-shared --extra-cflags=-mno-cygwin --extra-libs=-mno-cygwin
1392
@end example
1393

    
1394
and for a build with shared libraries
1395
@example
1396
./configure --target-os=mingw32 --enable-memalign-hack --enable-shared --disable-static --extra-cflags=-mno-cygwin --extra-libs=-mno-cygwin
1397
@end example
1398

    
1399
@section BeOS
1400

    
1401
The configure script should guess the configuration itself.
1402
Networking support is currently not finished.
1403
errno issues fixed by Andrew Bachmann.
1404

    
1405
Old stuff:
1406

    
1407
Fran├žois Revol - revol at free dot fr - April 2002
1408

    
1409
The configure script should guess the configuration itself,
1410
however I still did not test building on the net_server version of BeOS.
1411

    
1412
FFserver is broken (needs poll() implementation).
1413

    
1414
There are still issues with errno codes, which are negative in BeOS, and
1415
that FFmpeg negates when returning. This ends up turning errors into
1416
valid results, then crashes.
1417
(To be fixed)
1418

    
1419
@chapter Developers Guide
1420

    
1421
@section API
1422
@itemize @bullet
1423
@item libavcodec is the library containing the codecs (both encoding and
1424
decoding). Look at @file{libavcodec/apiexample.c} to see how to use it.
1425

    
1426
@item libavformat is the library containing the file format handling (mux and
1427
demux code for several formats). Look at @file{ffplay.c} to use it in a
1428
player. See @file{output_example.c} to use it to generate audio or video
1429
streams.
1430

    
1431
@end itemize
1432

    
1433
@section Integrating libavcodec or libavformat in your program
1434

    
1435
You can integrate all the source code of the libraries to link them
1436
statically to avoid any version problem. All you need is to provide a
1437
'config.mak' and a 'config.h' in the parent directory. See the defines
1438
generated by ./configure to understand what is needed.
1439

    
1440
You can use libavcodec or libavformat in your commercial program, but
1441
@emph{any patch you make must be published}. The best way to proceed is
1442
to send your patches to the FFmpeg mailing list.
1443

    
1444
@node Coding Rules
1445
@section Coding Rules
1446

    
1447
FFmpeg is programmed in the ISO C90 language with a few additional
1448
features from ISO C99, namely:
1449
@itemize @bullet
1450
@item
1451
the @samp{inline} keyword;
1452
@item
1453
@samp{//} comments;
1454
@item
1455
designated struct initializers (@samp{struct s x = @{ .i = 17 @};})
1456
@item
1457
compound literals (@samp{x = (struct s) @{ 17, 23 @};})
1458
@end itemize
1459

    
1460
These features are supported by all compilers we care about, so we will not
1461
accept patches to remove their use unless they absolutely do not impair
1462
clarity and performance.
1463

    
1464
All code must compile with GCC 2.95 and GCC 3.3. Currently, FFmpeg also
1465
compiles with several other compilers, such as the Compaq ccc compiler
1466
or Sun Studio 9, and we would like to keep it that way unless it would
1467
be exceedingly involved. To ensure compatibility, please do not use any
1468
additional C99 features or GCC extensions. Especially watch out for:
1469
@itemize @bullet
1470
@item
1471
mixing statements and declarations;
1472
@item
1473
@samp{long long} (use @samp{int64_t} instead);
1474
@item
1475
@samp{__attribute__} not protected by @samp{#ifdef __GNUC__} or similar;
1476
@item
1477
GCC statement expressions (@samp{(x = (@{ int y = 4; y; @})}).
1478
@end itemize
1479

    
1480
Indent size is 4.
1481
The presentation is the one specified by 'indent -i4 -kr -nut'.
1482
The TAB character is forbidden outside of Makefiles as is any
1483
form of trailing whitespace. Commits containing either will be
1484
rejected by the Subversion repository.
1485

    
1486
Main priority in FFmpeg is simplicity and small code size (=less
1487
bugs).
1488

    
1489
Comments: Use the JavaDoc/Doxygen
1490
format (see examples below) so that code documentation
1491
can be generated automatically. All nontrivial functions should have a comment
1492
above them explaining what the function does, even if it is just one sentence.
1493
All structures and their member variables should be documented, too.
1494
@example
1495
/**
1496
 * @@file mpeg.c
1497
 * MPEG codec.
1498
 * @@author ...
1499
 */
1500

    
1501
/**
1502
 * Summary sentence.
1503
 * more text ...
1504
 * ...
1505
 */
1506
typedef struct Foobar@{
1507
    int var1; /**< var1 description */
1508
    int var2; ///< var2 description
1509
    /** var3 description */
1510
    int var3;
1511
@} Foobar;
1512

    
1513
/**
1514
 * Summary sentence.
1515
 * more text ...
1516
 * ...
1517
 * @@param my_parameter description of my_parameter
1518
 * @@return return value description
1519
 */
1520
int myfunc(int my_parameter)
1521
...
1522
@end example
1523

    
1524
fprintf and printf are forbidden in libavformat and libavcodec,
1525
please use av_log() instead.
1526

    
1527
@section Development Policy
1528

    
1529
@enumerate
1530
@item
1531
   You must not commit code which breaks FFmpeg! (Meaning unfinished but
1532
   enabled code which breaks compilation or compiles but does not work or
1533
   breaks the regression tests)
1534
   You can commit unfinished stuff (for testing etc), but it must be disabled
1535
   (#ifdef etc) by default so it does not interfere with other developers'
1536
   work.
1537
@item
1538
   You do not have to over-test things. If it works for you, and you think it
1539
   should work for others, then commit. If your code has problems
1540
   (portability, triggers compiler bugs, unusual environment etc) they will be
1541
   reported and eventually fixed.
1542
@item
1543
   Do not commit unrelated changes together, split them into self-contained
1544
   pieces. Also do not forget that if part B depends on part A, but A does not
1545
   depend on B, then A can and should be committed first and separate from B.
1546
   Keeping changes well split into self-contained parts makes reviewing and
1547
   understanding them on the commit log mailing list easier. This also helps
1548
   in case of debugging later on.
1549
   Also if you have doubts about splitting or not splitting, do not hesitate to
1550
   ask/discuss it on the developer mailing list.
1551
@item
1552
   Do not change behavior of the program (renaming options etc) without
1553
   first discussing it on the ffmpeg-devel mailing list. Do not remove
1554
   functionality from the code. Just improve!
1555

    
1556
   Note: Redundant code can be removed.
1557
@item
1558
   Do not commit changes to the build system (Makefiles, configure script)
1559
   which change behavior, defaults etc, without asking first. The same
1560
   applies to compiler warning fixes, trivial looking fixes and to code
1561
   maintained by other developers. We usually have a reason for doing things
1562
   the way we do. Send your changes as patches to the ffmpeg-devel mailing
1563
   list, and if the code maintainers say OK, you may commit. This does not
1564
   apply to files you wrote and/or maintain.
1565
@item
1566
   We refuse source indentation and other cosmetic changes if they are mixed
1567
   with functional changes, such commits will be rejected and removed. Every
1568
   developer has his own indentation style, you should not change it. Of course
1569
   if you (re)write something, you can use your own style, even though we would
1570
   prefer if the indentation throughout FFmpeg was consistent (Many projects
1571
   force a given indentation style - we do not.). If you really need to make
1572
   indentation changes (try to avoid this), separate them strictly from real
1573
   changes.
1574

    
1575
   NOTE: If you had to put if()@{ .. @} over a large (> 5 lines) chunk of code,
1576
   then either do NOT change the indentation of the inner part within (do not
1577
   move it to the right)! or do so in a separate commit
1578
@item
1579
   Always fill out the commit log message. Describe in a few lines what you
1580
   changed and why. You can refer to mailing list postings if you fix a
1581
   particular bug. Comments such as "fixed!" or "Changed it." are unacceptable.
1582
@item
1583
   If you apply a patch by someone else, include the name and email address in
1584
   the log message. Since the ffmpeg-cvslog mailing list is publicly
1585
   archived you should add some SPAM protection to the email address. Send an
1586
   answer to ffmpeg-devel (or wherever you got the patch from) saying that
1587
   you applied the patch.
1588
@item
1589
   When applying patches that have been discussed (at length) on the mailing
1590
   list, reference the thread in the log message.
1591
@item
1592
    Do NOT commit to code actively maintained by others without permission.
1593
    Send a patch to ffmpeg-devel instead. If noone answers within a reasonable
1594
    timeframe (12h for build failures and security fixes, 3 days small changes,
1595
    1 week for big patches) then commit your patch if you think it is OK.
1596
    Also note, the maintainer can simply ask for more time to review!
1597
@item
1598
    Subscribe to the ffmpeg-cvslog mailing list. The diffs of all commits
1599
    are sent there and reviewed by all the other developers. Bugs and possible
1600
    improvements or general questions regarding commits are discussed there. We
1601
    expect you to react if problems with your code are uncovered.
1602
@item
1603
    Update the documentation if you change behavior or add features. If you are
1604
    unsure how best to do this, send a patch to ffmpeg-devel, the documentation
1605
    maintainer(s) will review and commit your stuff.
1606
@item
1607
    Try to keep important discussions and requests (also) on the public
1608
    developer mailing list, so that all developers can benefit from them.
1609
@item
1610
    Never write to unallocated memory, never write over the end of arrays,
1611
    always check values read from some untrusted source before using them
1612
    as array index or other risky things.
1613
@item
1614
    Remember to check if you need to bump versions for the specific libav
1615
    parts (libavutil, libavcodec, libavformat) you are changing. You need
1616
    to change the version integer and the version string.
1617
    Incrementing the first component means no backward compatibility to
1618
    previous versions (e.g. removal of a function from the public API).
1619
    Incrementing the second component means backward compatible change
1620
    (e.g. addition of a function to the public API).
1621
    Incrementing the third component means a noteworthy binary compatible
1622
    change (e.g. encoder bug fix that matters for the decoder).
1623
@item
1624
    If you add a new codec, remember to update the changelog, add it to
1625
    the supported codecs table in the documentation and bump the second
1626
    component of the @file{libavcodec} version number appropriately. If
1627
    it has a fourcc, add it to @file{libavformat/avienc.c}, even if it
1628
    is only a decoder.
1629
@item
1630
    Do not change code to hide warnings without ensuring that the underlying
1631
    logic is correct and thus the warning was inappropriate.
1632
@item
1633
    If you add a new file, give it a proper license header. Do not copy and
1634
    paste it from a random place, use an existing file as template.
1635
@end enumerate
1636

    
1637
We think our rules are not too hard. If you have comments, contact us.
1638

    
1639
Note, these rules are mostly borrowed from the MPlayer project.
1640

    
1641
@section Submitting patches
1642

    
1643
First, (@pxref{Coding Rules}) above if you did not yet.
1644

    
1645
When you submit your patch, try to send a unified diff (diff '-up'
1646
option). I cannot read other diffs :-)
1647

    
1648
Also please do not submit patches which contain several unrelated changes.
1649
Split them into individual self-contained patches; this makes reviewing
1650
them much easier.
1651

    
1652
Run the regression tests before submitting a patch so that you can
1653
verify that there are no big problems.
1654

    
1655
Patches should be posted as base64 encoded attachments (or any other
1656
encoding which ensures that the patch will not be trashed during
1657
transmission) to the ffmpeg-devel mailing list, see
1658
@url{http://lists.mplayerhq.hu/mailman/listinfo/ffmpeg-devel}
1659

    
1660
It also helps quite a bit if you tell us what the patch does (for example
1661
'replaces lrint by lrintf'), and why (for example '*BSD isn't C99 compliant
1662
and has no lrint()')
1663

    
1664
Also please if you send several patches, send each patch as separate mail,
1665
do not attach several unrelated patches to the same mail.
1666

    
1667
@section patch submission checklist
1668

    
1669
@enumerate
1670
@item
1671
    Do the regression tests pass with the patch applied?
1672
@item
1673
    Is the patch a unified diff?
1674
@item
1675
    Is the patch against latest FFmpeg SVN?
1676
@item
1677
    Are you subscribed to ffmpeg-dev?
1678
    (the list is subscribers only due to spam)
1679
@item
1680
    Have you checked that the changes are minimal, so that the same cannot be
1681
    achieved with a smaller patch and/or simpler final code?
1682
@item
1683
    If the change is to speed critical code, did you benchmark it?
1684
@item
1685
    If you did any benchmarks, did you provide them in the mail?
1686
@item
1687
    Have you checked that the patch does not introduce buffer overflows or
1688
    other security issues?
1689
@item
1690
    Is the patch created from the root of the source tree, so it can be
1691
    applied with @code{patch -p0}?
1692
@item
1693
    Does the patch not mix functional and cosmetic changes?
1694
@item
1695
    Did you add tabs or trailing whitespace to the code? Both are forbidden.
1696
@item
1697
    Is the patch attached to the email you send?
1698
@item
1699
    Is the mime type of the patch correct? It should be text/x-diff or
1700
    text/x-patch or at least text/plain and not application/octet-stream.
1701
@item
1702
    If the patch fixes a bug, did you provide a verbose analysis of the bug?
1703
@item
1704
    If the patch fixes a bug, did you provide enough information, including
1705
    a sample, so the bug can be reproduced and the fix can be verified?
1706
@item
1707
    Did you provide a verbose summary about what the patch does change?
1708
@item
1709
    Did you provide a verbose explanation why it changes things like it does?
1710
@item
1711
    Did you provide a verbose summary of the user visible advantages and
1712
    disadvantages if the patch is applied?
1713
@item
1714
    Did you provide an example so we can verify the new feature added by the
1715
    patch easily?
1716
@item
1717
    If you added a new file, did you insert a license header? It should be
1718
    taken from FFmpeg, not randomly copied and pasted from somewhere else.
1719
@item
1720
    Did you provide a suggestion for a clear commit log message?
1721
@end enumerate
1722

    
1723
@section Patch review process
1724

    
1725
All patches posted to ffmpeg-devel will be reviewed, unless they contain a
1726
clear note that the patch is not for SVN.
1727
Reviews and comments will be posted as replies to the patch on the
1728
mailing list. The patch submitter then has to take care of every comment,
1729
that can be by resubmitting a changed patch or by discussion. Resubmitted
1730
patches will themselves be reviewed like any other patch. If at some point
1731
a patch passes review with no comments then it is approved, that can for
1732
simple and small patches happen immediately while large patches will generally
1733
have to be changed and reviewed many times before they are approved.
1734
After a patch is approved it will be committed to the repository.
1735

    
1736
We will review all submitted patches, but sometimes we are quite busy so
1737
especially for large patches this can take several weeks.
1738

    
1739
When resubmitting patches, please do not make any significant changes
1740
not related to the comments received during review. Such patches will
1741
be rejected. Instead, submit  significant changes or new features as
1742
separate patches.
1743

    
1744
@section Regression tests
1745

    
1746
Before submitting a patch (or committing to the repository), you should at least
1747
test that you did not break anything.
1748

    
1749
The regression tests build a synthetic video stream and a synthetic
1750
audio stream. These are then encoded and decoded with all codecs or
1751
formats. The CRC (or MD5) of each generated file is recorded in a
1752
result file. A 'diff' is launched to compare the reference results and
1753
the result file.
1754

    
1755
The regression tests then go on to test the FFserver code with a
1756
limited set of streams. It is important that this step runs correctly
1757
as well.
1758

    
1759
Run 'make test' to test all the codecs and formats.
1760

    
1761
Run 'make fulltest' to test all the codecs, formats and FFserver.
1762

    
1763
[Of course, some patches may change the results of the regression tests. In
1764
this case, the reference results of the regression tests shall be modified
1765
accordingly].
1766

    
1767
@bye