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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
@item PTX          @tab   @tab X @tab V.Flash PTX format
968
@end multitable
969

    
970
@code{X} means that encoding (resp. decoding) is supported.
971

    
972
@section Video Codecs
973

    
974
@multitable @columnfractions .4 .1 .1 .4
975
@item Supported Codec @tab Encoding @tab Decoding @tab Comments
976
@item MPEG-1 video           @tab  X  @tab  X
977
@item MPEG-2 video           @tab  X  @tab  X
978
@item MPEG-4                 @tab  X  @tab  X
979
@item MSMPEG4 V1             @tab  X  @tab  X
980
@item MSMPEG4 V2             @tab  X  @tab  X
981
@item MSMPEG4 V3             @tab  X  @tab  X
982
@item WMV7                   @tab  X  @tab  X
983
@item WMV8                   @tab  X  @tab  X @tab not completely working
984
@item WMV9                   @tab     @tab  X @tab not completely working
985
@item VC1                    @tab     @tab  X
986
@item H.261                  @tab  X  @tab  X
987
@item H.263(+)               @tab  X  @tab  X @tab also known as RealVideo 1.0
988
@item H.264                  @tab     @tab  X
989
@item RealVideo 1.0          @tab  X  @tab  X
990
@item RealVideo 2.0          @tab  X  @tab  X
991
@item MJPEG                  @tab  X  @tab  X
992
@item lossless MJPEG         @tab  X  @tab  X
993
@item JPEG-LS                @tab  X  @tab  X @tab fourcc: MJLS, lossless and near-lossless is supported
994
@item Apple MJPEG-B          @tab     @tab  X
995
@item Sunplus MJPEG          @tab     @tab  X @tab fourcc: SP5X
996
@item DV                     @tab  X  @tab  X
997
@item HuffYUV                @tab  X  @tab  X
998
@item FFmpeg Video 1         @tab  X  @tab  X @tab experimental lossless codec (fourcc: FFV1)
999
@item FFmpeg Snow            @tab  X  @tab  X @tab experimental wavelet codec (fourcc: SNOW)
1000
@item Asus v1                @tab  X  @tab  X @tab fourcc: ASV1
1001
@item Asus v2                @tab  X  @tab  X @tab fourcc: ASV2
1002
@item Creative YUV           @tab     @tab  X @tab fourcc: CYUV
1003
@item Sorenson Video 1       @tab  X  @tab  X @tab fourcc: SVQ1
1004
@item Sorenson Video 3       @tab     @tab  X @tab fourcc: SVQ3
1005
@item On2 VP3                @tab     @tab  X @tab still experimental
1006
@item On2 VP5                @tab     @tab  X @tab fourcc: VP50
1007
@item On2 VP6                @tab     @tab  X @tab fourcc: VP60,VP61,VP62
1008
@item Theora                 @tab  X  @tab  X @tab still experimental
1009
@item Intel Indeo 3          @tab     @tab  X
1010
@item FLV                    @tab  X  @tab  X @tab Sorenson H.263 used in Flash
1011
@item Flash Screen Video     @tab  X  @tab  X @tab fourcc: FSV1
1012
@item ATI VCR1               @tab     @tab  X @tab fourcc: VCR1
1013
@item ATI VCR2               @tab     @tab  X @tab fourcc: VCR2
1014
@item Cirrus Logic AccuPak   @tab     @tab  X @tab fourcc: CLJR
1015
@item 4X Video               @tab     @tab  X @tab Used in certain computer games.
1016
@item Sony Playstation MDEC  @tab     @tab  X
1017
@item Id RoQ                 @tab     @tab  X @tab Used in Quake III, Jedi Knight 2, other computer games.
1018
@item Xan/WC3                @tab     @tab  X @tab Used in Wing Commander III .MVE files.
1019
@item Interplay Video        @tab     @tab  X @tab Used in Interplay .MVE files.
1020
@item Apple Animation        @tab     @tab  X @tab fourcc: 'rle '
1021
@item Apple Graphics         @tab     @tab  X @tab fourcc: 'smc '
1022
@item Apple Video            @tab     @tab  X @tab fourcc: rpza
1023
@item Apple QuickDraw        @tab     @tab  X @tab fourcc: qdrw
1024
@item Cinepak                @tab     @tab  X
1025
@item Microsoft RLE          @tab     @tab  X
1026
@item Microsoft Video-1      @tab     @tab  X
1027
@item Westwood VQA           @tab     @tab  X
1028
@item Id Cinematic Video     @tab     @tab  X @tab Used in Quake II.
1029
@item Planar RGB             @tab     @tab  X @tab fourcc: 8BPS
1030
@item FLIC video             @tab     @tab  X
1031
@item Duck TrueMotion v1     @tab     @tab  X @tab fourcc: DUCK
1032
@item Duck TrueMotion v2     @tab     @tab  X @tab fourcc: TM20
1033
@item VMD Video              @tab     @tab  X @tab Used in Sierra VMD files.
1034
@item MSZH                   @tab     @tab  X @tab Part of LCL
1035
@item ZLIB                   @tab  X  @tab  X @tab Part of LCL, encoder experimental
1036
@item TechSmith Camtasia     @tab     @tab  X @tab fourcc: TSCC
1037
@item IBM Ultimotion         @tab     @tab  X @tab fourcc: ULTI
1038
@item Miro VideoXL           @tab     @tab  X @tab fourcc: VIXL
1039
@item QPEG                   @tab     @tab  X @tab fourccs: QPEG, Q1.0, Q1.1
1040
@item LOCO                   @tab     @tab  X @tab
1041
@item Winnov WNV1            @tab     @tab  X @tab
1042
@item Autodesk Animator Studio Codec  @tab     @tab  X @tab fourcc: AASC
1043
@item Fraps FPS1             @tab     @tab  X @tab
1044
@item CamStudio              @tab     @tab  X @tab fourcc: CSCD
1045
@item American Laser Games Video  @tab    @tab X @tab Used in games like Mad Dog McCree
1046
@item ZMBV                   @tab   X @tab  X @tab Encoder works only on PAL8
1047
@item AVS Video              @tab     @tab  X @tab Video encoding used by the Creature Shock game.
1048
@item Smacker Video          @tab     @tab  X @tab Video encoding used in Smacker.
1049
@item RTjpeg                 @tab     @tab  X @tab Video encoding used in NuppelVideo files.
1050
@item KMVC                   @tab     @tab  X @tab Codec used in Worms games.
1051
@item VMware Video           @tab     @tab  X @tab Codec used in videos captured by VMware.
1052
@item Cin Video              @tab     @tab  X @tab Codec used in Delphine Software games.
1053
@item Tiertex Seq Video      @tab     @tab  X @tab Codec used in DOS CDROM FlashBack game.
1054
@item DXA Video              @tab     @tab  X @tab Codec originally used in Feeble Files game.
1055
@item AVID DNxHD             @tab     @tab  X @tab aka SMPTE VC3
1056
@item C93 Video              @tab     @tab  X @tab Codec used in Cyberia game.
1057
@item THP                    @tab     @tab  X @tab Used on the Nintendo GameCube.
1058
@item Bethsoft VID           @tab     @tab  X @tab Used in some games from Bethesda Softworks.
1059
@end multitable
1060

    
1061
@code{X} means that encoding (resp. decoding) is supported.
1062

    
1063
@section Audio Codecs
1064

    
1065
@multitable @columnfractions .4 .1 .1 .1 .7
1066
@item Supported Codec @tab Encoding @tab Decoding @tab Comments
1067
@item MPEG audio layer 2     @tab  IX  @tab  IX
1068
@item MPEG audio layer 1/3   @tab IX   @tab  IX
1069
@tab MP3 encoding is supported through the external library LAME.
1070
@item AC3                    @tab  IX  @tab  IX
1071
@tab liba52 is used internally for decoding.
1072
@item Vorbis                 @tab  X   @tab  X
1073
@item WMA V1/V2              @tab X    @tab X
1074
@item AAC                    @tab X    @tab X
1075
@tab Supported through the external library libfaac/libfaad.
1076
@item Microsoft ADPCM        @tab X    @tab X
1077
@item MS IMA ADPCM           @tab X    @tab X
1078
@item QT IMA ADPCM           @tab      @tab X
1079
@item 4X IMA ADPCM           @tab      @tab X
1080
@item G.726  ADPCM           @tab X    @tab X
1081
@item Duck DK3 IMA ADPCM     @tab      @tab X
1082
@tab Used in some Sega Saturn console games.
1083
@item Duck DK4 IMA ADPCM     @tab      @tab X
1084
@tab Used in some Sega Saturn console games.
1085
@item Westwood Studios IMA ADPCM @tab      @tab X
1086
@tab Used in Westwood Studios games like Command and Conquer.
1087
@item SMJPEG IMA ADPCM       @tab      @tab X
1088
@tab Used in certain Loki game ports.
1089
@item CD-ROM XA ADPCM        @tab      @tab X
1090
@item CRI ADX ADPCM          @tab X    @tab X
1091
@tab Used in Sega Dreamcast games.
1092
@item Electronic Arts ADPCM  @tab      @tab X
1093
@tab Used in various EA titles.
1094
@item Creative ADPCM         @tab      @tab X
1095
@tab 16 -> 4, 8 -> 4, 8 -> 3, 8 -> 2
1096
@item THP ADPCM              @tab      @tab X
1097
@tab Used on the Nintendo GameCube.
1098
@item RA144                  @tab      @tab X
1099
@tab Real 14400 bit/s codec
1100
@item RA288                  @tab      @tab X
1101
@tab Real 28800 bit/s codec
1102
@item RADnet                 @tab X    @tab IX
1103
@tab Real low bitrate AC3 codec, liba52 is used for decoding.
1104
@item AMR-NB                 @tab X    @tab X
1105
@tab Supported through an external library.
1106
@item AMR-WB                 @tab X    @tab X
1107
@tab Supported through an external library.
1108
@item DV audio               @tab      @tab X
1109
@item Id RoQ DPCM            @tab X    @tab X
1110
@tab Used in Quake III, Jedi Knight 2, other computer games.
1111
@item Interplay MVE DPCM     @tab      @tab X
1112
@tab Used in various Interplay computer games.
1113
@item Xan DPCM               @tab      @tab X
1114
@tab Used in Origin's Wing Commander IV AVI files.
1115
@item Sierra Online DPCM     @tab      @tab X
1116
@tab Used in Sierra Online game audio files.
1117
@item Apple MACE 3           @tab      @tab X
1118
@item Apple MACE 6           @tab      @tab X
1119
@item FLAC lossless audio    @tab X    @tab X
1120
@item Shorten lossless audio @tab      @tab X
1121
@item Apple lossless audio   @tab      @tab X
1122
@tab QuickTime fourcc 'alac'
1123
@item FFmpeg Sonic           @tab X    @tab X
1124
@tab experimental lossy/lossless codec
1125
@item Qdesign QDM2           @tab      @tab X
1126
@tab there are still some distortions
1127
@item Real COOK              @tab      @tab X
1128
@tab All versions except 5.1 are supported
1129
@item DSP Group TrueSpeech   @tab      @tab X
1130
@item True Audio (TTA)       @tab      @tab X
1131
@item Smacker Audio          @tab      @tab X
1132
@item WavPack Audio          @tab      @tab X
1133
@item Cin Audio              @tab      @tab X
1134
@tab Codec used in Delphine Software games.
1135
@item Intel Music Coder      @tab      @tab X
1136
@item Musepack               @tab      @tab X
1137
@tab Only SV7 is supported
1138
@item DT$ Coherent Audio     @tab      @tab X
1139
@item ATRAC 3                @tab      @tab X
1140
@end multitable
1141

    
1142
@code{X} means that encoding (resp. decoding) is supported.
1143

    
1144
@code{I} means that an integer-only version is available, too (ensures high
1145
performance on systems without hardware floating point support).
1146

    
1147
@chapter Platform Specific information
1148

    
1149
@section BSD
1150

    
1151
BSD make will not build FFmpeg, you need to install and use GNU Make
1152
(@file{gmake}).
1153

    
1154
@section Windows
1155

    
1156
To get help and instructions for using FFmpeg under Windows, check out
1157
the FFmpeg Windows Help Forum at
1158
@url{http://arrozcru.no-ip.org/ffmpeg/}.
1159

    
1160
@subsection Native Windows compilation
1161

    
1162
@itemize
1163
@item Install the current versions of MSYS and MinGW from
1164
@url{http://www.mingw.org/}. You can find detailed installation
1165
instructions in the download section and the FAQ.
1166

    
1167
NOTE: Use at least bash 3.1. Older versions are known to be failing on the
1168
configure script.
1169

    
1170
@item If you want to test the FFplay, also download
1171
the MinGW development library of SDL 1.2.x
1172
(@file{SDL-devel-1.2.x-mingw32.tar.gz}) from
1173
@url{http://www.libsdl.org}. Unpack it in a temporary directory, and
1174
unpack the archive @file{i386-mingw32msvc.tar.gz} in the MinGW tool
1175
directory. Edit the @file{sdl-config} script so that it gives the
1176
correct SDL directory when invoked.
1177

    
1178
@item Extract the current version of FFmpeg.
1179

    
1180
@item Start the MSYS shell (file @file{msys.bat}).
1181

    
1182
@item Change to the FFmpeg directory and follow
1183
 the instructions of how to compile FFmpeg (file
1184
@file{INSTALL}). Usually, launching @file{./configure} and @file{make}
1185
suffices. If you have problems using SDL, verify that
1186
@file{sdl-config} can be launched from the MSYS command line.
1187

    
1188
@item You can install FFmpeg in @file{Program Files/FFmpeg} by typing
1189
@file{make install}. Do not forget to copy @file{SDL.dll} to the place
1190
you launch @file{ffplay} from.
1191

    
1192
@end itemize
1193

    
1194
Notes:
1195
@itemize
1196

    
1197
@item The target @file{make wininstaller} can be used to create a
1198
Nullsoft based Windows installer for FFmpeg and FFplay. @file{SDL.dll}
1199
must be copied to the FFmpeg directory in order to build the
1200
installer.
1201

    
1202
@item By using @code{./configure --enable-shared} when configuring FFmpeg,
1203
you can build @file{avcodec.dll} and @file{avformat.dll}. With
1204
@code{make install} you install the FFmpeg DLLs and the associated
1205
headers in @file{Program Files/FFmpeg}.
1206

    
1207
@item Visual C++ compatibility: If you used @code{./configure --enable-shared}
1208
when configuring FFmpeg, FFmpeg tries to use the Microsoft Visual
1209
C++ @code{lib} tool to build @code{avcodec.lib} and
1210
@code{avformat.lib}. With these libraries you can link your Visual C++
1211
code directly with the FFmpeg DLLs (see below).
1212

    
1213
@end itemize
1214

    
1215
@subsection Visual C++ compatibility
1216

    
1217
FFmpeg will not compile under Visual C++ -- and it has too many
1218
dependencies on the GCC compiler to make a port viable. However,
1219
if you want to use the FFmpeg libraries in your own applications,
1220
you can still compile those applications using Visual C++. An
1221
important restriction to this is that you have to use the
1222
dynamically linked versions of the FFmpeg libraries (i.e. the
1223
DLLs), and you have to make sure that Visual-C++-compatible
1224
import libraries are created during the FFmpeg build process.
1225

    
1226
This description of how to use the FFmpeg libraries with Visual C++ is
1227
based on Visual C++ 2005 Express Edition Beta 2. If you have a different
1228
version, you might have to modify the procedures slightly.
1229

    
1230
Here are the step-by-step instructions for building the FFmpeg libraries
1231
so they can be used with Visual C++:
1232

    
1233
@enumerate
1234

    
1235
@item Install Visual C++ (if you have not done so already).
1236

    
1237
@item Install MinGW and MSYS as described above.
1238

    
1239
@item Add a call to @file{vcvars32.bat} (which sets up the environment
1240
variables for the Visual C++ tools) as the first line of
1241
@file{msys.bat}. The standard location for @file{vcvars32.bat} is
1242
@file{C:\Program Files\Microsoft Visual Studio 8\VC\bin\vcvars32.bat},
1243
and the standard location for @file{msys.bat} is
1244
@file{C:\msys\1.0\msys.bat}. If this corresponds to your setup, add the
1245
following line as the first line of @file{msys.bat}:
1246

    
1247
@code{call "C:\Program Files\Microsoft Visual Studio 8\VC\bin\vcvars32.bat"}
1248

    
1249
@item Start the MSYS shell (file @file{msys.bat}) and type @code{link.exe}.
1250
If you get a help message with the command line options of @code{link.exe},
1251
this means your environment variables are set up correctly, the
1252
Microsoft linker is on the path and will be used by FFmpeg to
1253
create Visual-C++-compatible import libraries.
1254

    
1255
@item Extract the current version of FFmpeg and change to the FFmpeg directory.
1256

    
1257
@item Type the command
1258
@code{./configure --enable-shared --disable-static --enable-memalign-hack}
1259
to configure and, if that did not produce any errors,
1260
type @code{make} to build FFmpeg.
1261

    
1262
@item The subdirectories @file{libavformat}, @file{libavcodec}, and
1263
@file{libavutil} should now contain the files @file{avformat.dll},
1264
@file{avformat.lib}, @file{avcodec.dll}, @file{avcodec.lib},
1265
@file{avutil.dll}, and @file{avutil.lib}, respectively. Copy the three
1266
DLLs to your System32 directory (typically @file{C:\Windows\System32}).
1267

    
1268
@end enumerate
1269

    
1270
And here is how to use these libraries with Visual C++:
1271

    
1272
@enumerate
1273

    
1274
@item Create a new console application ("File / New / Project") and then
1275
select "Win32 Console Application". On the appropriate page of the
1276
Application Wizard, uncheck the "Precompiled headers" option.
1277

    
1278
@item Write the source code for your application, or, for testing, just
1279
copy the code from an existing sample application into the source file
1280
that Visual C++ has already created for you. (Note that your source
1281
filehas to have a @code{.cpp} extension; otherwise, Visual C++ will not
1282
compile the FFmpeg headers correctly because in C mode, it does not
1283
recognize the @code{inline} keyword.)  For example, you can copy
1284
@file{output_example.c} from the FFmpeg distribution (but you will
1285
have to make minor modifications so the code will compile under
1286
C++, see below).
1287

    
1288
@item Open the "Project / Properties" dialog box. In the "Configuration"
1289
combo box, select "All Configurations" so that the changes you make will
1290
affect both debug and release builds. In the tree view on the left hand
1291
side, select "C/C++ / General", then edit the "Additional Include
1292
Directories" setting to contain the complete paths to the
1293
@file{libavformat}, @file{libavcodec}, and @file{libavutil}
1294
subdirectories of your FFmpeg directory. Note that the directories have
1295
to be separated using semicolons. Now select "Linker / General" from the
1296
tree view and edit the "Additional Library Directories" setting to
1297
contain the same three directories.
1298

    
1299
@item Still in the "Project / Properties" dialog box, select "Linker / Input"
1300
from the tree view, then add the files @file{avformat.lib},
1301
@file{avcodec.lib}, and @file{avutil.lib} to the end of the "Additional
1302
Dependencies". Note that the names of the libraries have to be separated
1303
using spaces.
1304

    
1305
@item Now, select "C/C++ / Code Generation" from the tree view. Select
1306
"Debug" in the "Configuration" combo box. Make sure that "Runtime
1307
Library" is set to "Multi-threaded Debug DLL". Then, select "Release" in
1308
the "Configuration" combo box and make sure that "Runtime Library" is
1309
set to "Multi-threaded DLL".
1310

    
1311
@item Click "OK" to close the "Project / Properties" dialog box and build
1312
the application. Hopefully, it should compile and run cleanly. If you
1313
used @file{output_example.c} as your sample application, you will get a
1314
few compiler errors, but they are easy to fix. The first type of error
1315
occurs because Visual C++ does not allow an @code{int} to be converted to
1316
an @code{enum} without a cast. To solve the problem, insert the required
1317
casts (this error occurs once for a @code{CodecID} and once for a
1318
@code{CodecType}).  The second type of error occurs because C++ requires
1319
the return value of @code{malloc} to be cast to the exact type of the
1320
pointer it is being assigned to. Visual C++ will complain that, for
1321
example, @code{(void *)} is being assigned to @code{(uint8_t *)} without
1322
an explicit cast. So insert an explicit cast in these places to silence
1323
the compiler. The third type of error occurs because the @code{snprintf}
1324
library function is called @code{_snprintf} under Visual C++.  So just
1325
add an underscore to fix the problem. With these changes,
1326
@file{output_example.c} should compile under Visual C++, and the
1327
resulting executable should produce valid video files.
1328

    
1329
@end enumerate
1330

    
1331
@subsection Cross compilation for Windows with Linux
1332

    
1333
You must use the MinGW cross compilation tools available at
1334
@url{http://www.mingw.org/}.
1335

    
1336
Then configure FFmpeg with the following options:
1337
@example
1338
./configure --target-os=mingw32 --cross-prefix=i386-mingw32msvc-
1339
@end example
1340
(you can change the cross-prefix according to the prefix chosen for the
1341
MinGW tools).
1342

    
1343
Then you can easily test FFmpeg with Wine
1344
(@url{http://www.winehq.com/}).
1345

    
1346
@subsection Compilation under Cygwin
1347

    
1348
Cygwin works very much like Unix.
1349

    
1350
Just install your Cygwin with all the "Base" packages, plus the
1351
following "Devel" ones:
1352
@example
1353
binutils, gcc-core, make, subversion
1354
@end example
1355

    
1356
Do not install binutils-20060709-1 (they are buggy on shared builds);
1357
use binutils-20050610-1 instead.
1358

    
1359
Then run
1360

    
1361
@example
1362
./configure --enable-static --disable-shared
1363
@end example
1364

    
1365
to make a static build or
1366

    
1367
@example
1368
./configure --enable-shared --disable-static
1369
@end example
1370

    
1371
to build shared libraries.
1372

    
1373
If you want to build FFmpeg with additional libraries, download Cygwin
1374
"Devel" packages for Ogg and Vorbis from any Cygwin packages repository
1375
and/or SDL, xvid, faac, faad2 packages from Cygwin Ports,
1376
(@url{http://cygwinports.dotsrc.org/}).
1377

    
1378
@subsection Crosscompilation for Windows under Cygwin
1379

    
1380
With Cygwin you can create Windows binaries that do not need the cygwin1.dll.
1381

    
1382
Just install your Cygwin as explained before, plus these additional
1383
"Devel" packages:
1384
@example
1385
gcc-mingw-core, mingw-runtime, mingw-zlib
1386
@end example
1387

    
1388
and add some special flags to your configure invocation.
1389

    
1390
For a static build run
1391
@example
1392
./configure --target-os=mingw32 --enable-memalign-hack --enable-static --disable-shared --extra-cflags=-mno-cygwin --extra-libs=-mno-cygwin
1393
@end example
1394

    
1395
and for a build with shared libraries
1396
@example
1397
./configure --target-os=mingw32 --enable-memalign-hack --enable-shared --disable-static --extra-cflags=-mno-cygwin --extra-libs=-mno-cygwin
1398
@end example
1399

    
1400
@section BeOS
1401

    
1402
The configure script should guess the configuration itself.
1403
Networking support is currently not finished.
1404
errno issues fixed by Andrew Bachmann.
1405

    
1406
Old stuff:
1407

    
1408
Fran├žois Revol - revol at free dot fr - April 2002
1409

    
1410
The configure script should guess the configuration itself,
1411
however I still did not test building on the net_server version of BeOS.
1412

    
1413
FFserver is broken (needs poll() implementation).
1414

    
1415
There are still issues with errno codes, which are negative in BeOS, and
1416
that FFmpeg negates when returning. This ends up turning errors into
1417
valid results, then crashes.
1418
(To be fixed)
1419

    
1420
@chapter Developers Guide
1421

    
1422
@section API
1423
@itemize @bullet
1424
@item libavcodec is the library containing the codecs (both encoding and
1425
decoding). Look at @file{libavcodec/apiexample.c} to see how to use it.
1426

    
1427
@item libavformat is the library containing the file format handling (mux and
1428
demux code for several formats). Look at @file{ffplay.c} to use it in a
1429
player. See @file{output_example.c} to use it to generate audio or video
1430
streams.
1431

    
1432
@end itemize
1433

    
1434
@section Integrating libavcodec or libavformat in your program
1435

    
1436
You can integrate all the source code of the libraries to link them
1437
statically to avoid any version problem. All you need is to provide a
1438
'config.mak' and a 'config.h' in the parent directory. See the defines
1439
generated by ./configure to understand what is needed.
1440

    
1441
You can use libavcodec or libavformat in your commercial program, but
1442
@emph{any patch you make must be published}. The best way to proceed is
1443
to send your patches to the FFmpeg mailing list.
1444

    
1445
@node Coding Rules
1446
@section Coding Rules
1447

    
1448
FFmpeg is programmed in the ISO C90 language with a few additional
1449
features from ISO C99, namely:
1450
@itemize @bullet
1451
@item
1452
the @samp{inline} keyword;
1453
@item
1454
@samp{//} comments;
1455
@item
1456
designated struct initializers (@samp{struct s x = @{ .i = 17 @};})
1457
@item
1458
compound literals (@samp{x = (struct s) @{ 17, 23 @};})
1459
@end itemize
1460

    
1461
These features are supported by all compilers we care about, so we will not
1462
accept patches to remove their use unless they absolutely do not impair
1463
clarity and performance.
1464

    
1465
All code must compile with GCC 2.95 and GCC 3.3. Currently, FFmpeg also
1466
compiles with several other compilers, such as the Compaq ccc compiler
1467
or Sun Studio 9, and we would like to keep it that way unless it would
1468
be exceedingly involved. To ensure compatibility, please do not use any
1469
additional C99 features or GCC extensions. Especially watch out for:
1470
@itemize @bullet
1471
@item
1472
mixing statements and declarations;
1473
@item
1474
@samp{long long} (use @samp{int64_t} instead);
1475
@item
1476
@samp{__attribute__} not protected by @samp{#ifdef __GNUC__} or similar;
1477
@item
1478
GCC statement expressions (@samp{(x = (@{ int y = 4; y; @})}).
1479
@end itemize
1480

    
1481
Indent size is 4.
1482
The presentation is the one specified by 'indent -i4 -kr -nut'.
1483
The TAB character is forbidden outside of Makefiles as is any
1484
form of trailing whitespace. Commits containing either will be
1485
rejected by the Subversion repository.
1486

    
1487
Main priority in FFmpeg is simplicity and small code size (=less
1488
bugs).
1489

    
1490
Comments: Use the JavaDoc/Doxygen
1491
format (see examples below) so that code documentation
1492
can be generated automatically. All nontrivial functions should have a comment
1493
above them explaining what the function does, even if it is just one sentence.
1494
All structures and their member variables should be documented, too.
1495
@example
1496
/**
1497
 * @@file mpeg.c
1498
 * MPEG codec.
1499
 * @@author ...
1500
 */
1501

    
1502
/**
1503
 * Summary sentence.
1504
 * more text ...
1505
 * ...
1506
 */
1507
typedef struct Foobar@{
1508
    int var1; /**< var1 description */
1509
    int var2; ///< var2 description
1510
    /** var3 description */
1511
    int var3;
1512
@} Foobar;
1513

    
1514
/**
1515
 * Summary sentence.
1516
 * more text ...
1517
 * ...
1518
 * @@param my_parameter description of my_parameter
1519
 * @@return return value description
1520
 */
1521
int myfunc(int my_parameter)
1522
...
1523
@end example
1524

    
1525
fprintf and printf are forbidden in libavformat and libavcodec,
1526
please use av_log() instead.
1527

    
1528
@section Development Policy
1529

    
1530
@enumerate
1531
@item
1532
   You must not commit code which breaks FFmpeg! (Meaning unfinished but
1533
   enabled code which breaks compilation or compiles but does not work or
1534
   breaks the regression tests)
1535
   You can commit unfinished stuff (for testing etc), but it must be disabled
1536
   (#ifdef etc) by default so it does not interfere with other developers'
1537
   work.
1538
@item
1539
   You do not have to over-test things. If it works for you, and you think it
1540
   should work for others, then commit. If your code has problems
1541
   (portability, triggers compiler bugs, unusual environment etc) they will be
1542
   reported and eventually fixed.
1543
@item
1544
   Do not commit unrelated changes together, split them into self-contained
1545
   pieces. Also do not forget that if part B depends on part A, but A does not
1546
   depend on B, then A can and should be committed first and separate from B.
1547
   Keeping changes well split into self-contained parts makes reviewing and
1548
   understanding them on the commit log mailing list easier. This also helps
1549
   in case of debugging later on.
1550
   Also if you have doubts about splitting or not splitting, do not hesitate to
1551
   ask/discuss it on the developer mailing list.
1552
@item
1553
   Do not change behavior of the program (renaming options etc) without
1554
   first discussing it on the ffmpeg-devel mailing list. Do not remove
1555
   functionality from the code. Just improve!
1556

    
1557
   Note: Redundant code can be removed.
1558
@item
1559
   Do not commit changes to the build system (Makefiles, configure script)
1560
   which change behavior, defaults etc, without asking first. The same
1561
   applies to compiler warning fixes, trivial looking fixes and to code
1562
   maintained by other developers. We usually have a reason for doing things
1563
   the way we do. Send your changes as patches to the ffmpeg-devel mailing
1564
   list, and if the code maintainers say OK, you may commit. This does not
1565
   apply to files you wrote and/or maintain.
1566
@item
1567
   We refuse source indentation and other cosmetic changes if they are mixed
1568
   with functional changes, such commits will be rejected and removed. Every
1569
   developer has his own indentation style, you should not change it. Of course
1570
   if you (re)write something, you can use your own style, even though we would
1571
   prefer if the indentation throughout FFmpeg was consistent (Many projects
1572
   force a given indentation style - we do not.). If you really need to make
1573
   indentation changes (try to avoid this), separate them strictly from real
1574
   changes.
1575

    
1576
   NOTE: If you had to put if()@{ .. @} over a large (> 5 lines) chunk of code,
1577
   then either do NOT change the indentation of the inner part within (do not
1578
   move it to the right)! or do so in a separate commit
1579
@item
1580
   Always fill out the commit log message. Describe in a few lines what you
1581
   changed and why. You can refer to mailing list postings if you fix a
1582
   particular bug. Comments such as "fixed!" or "Changed it." are unacceptable.
1583
@item
1584
   If you apply a patch by someone else, include the name and email address in
1585
   the log message. Since the ffmpeg-cvslog mailing list is publicly
1586
   archived you should add some SPAM protection to the email address. Send an
1587
   answer to ffmpeg-devel (or wherever you got the patch from) saying that
1588
   you applied the patch.
1589
@item
1590
   When applying patches that have been discussed (at length) on the mailing
1591
   list, reference the thread in the log message.
1592
@item
1593
    Do NOT commit to code actively maintained by others without permission.
1594
    Send a patch to ffmpeg-devel instead. If noone answers within a reasonable
1595
    timeframe (12h for build failures and security fixes, 3 days small changes,
1596
    1 week for big patches) then commit your patch if you think it is OK.
1597
    Also note, the maintainer can simply ask for more time to review!
1598
@item
1599
    Subscribe to the ffmpeg-cvslog mailing list. The diffs of all commits
1600
    are sent there and reviewed by all the other developers. Bugs and possible
1601
    improvements or general questions regarding commits are discussed there. We
1602
    expect you to react if problems with your code are uncovered.
1603
@item
1604
    Update the documentation if you change behavior or add features. If you are
1605
    unsure how best to do this, send a patch to ffmpeg-devel, the documentation
1606
    maintainer(s) will review and commit your stuff.
1607
@item
1608
    Try to keep important discussions and requests (also) on the public
1609
    developer mailing list, so that all developers can benefit from them.
1610
@item
1611
    Never write to unallocated memory, never write over the end of arrays,
1612
    always check values read from some untrusted source before using them
1613
    as array index or other risky things.
1614
@item
1615
    Remember to check if you need to bump versions for the specific libav
1616
    parts (libavutil, libavcodec, libavformat) you are changing. You need
1617
    to change the version integer and the version string.
1618
    Incrementing the first component means no backward compatibility to
1619
    previous versions (e.g. removal of a function from the public API).
1620
    Incrementing the second component means backward compatible change
1621
    (e.g. addition of a function to the public API).
1622
    Incrementing the third component means a noteworthy binary compatible
1623
    change (e.g. encoder bug fix that matters for the decoder).
1624
@item
1625
    If you add a new codec, remember to update the changelog, add it to
1626
    the supported codecs table in the documentation and bump the second
1627
    component of the @file{libavcodec} version number appropriately. If
1628
    it has a fourcc, add it to @file{libavformat/avienc.c}, even if it
1629
    is only a decoder.
1630
@item
1631
    Do not change code to hide warnings without ensuring that the underlying
1632
    logic is correct and thus the warning was inappropriate.
1633
@item
1634
    If you add a new file, give it a proper license header. Do not copy and
1635
    paste it from a random place, use an existing file as template.
1636
@end enumerate
1637

    
1638
We think our rules are not too hard. If you have comments, contact us.
1639

    
1640
Note, these rules are mostly borrowed from the MPlayer project.
1641

    
1642
@section Submitting patches
1643

    
1644
First, (@pxref{Coding Rules}) above if you did not yet.
1645

    
1646
When you submit your patch, try to send a unified diff (diff '-up'
1647
option). I cannot read other diffs :-)
1648

    
1649
Also please do not submit patches which contain several unrelated changes.
1650
Split them into individual self-contained patches; this makes reviewing
1651
them much easier.
1652

    
1653
Run the regression tests before submitting a patch so that you can
1654
verify that there are no big problems.
1655

    
1656
Patches should be posted as base64 encoded attachments (or any other
1657
encoding which ensures that the patch will not be trashed during
1658
transmission) to the ffmpeg-devel mailing list, see
1659
@url{http://lists.mplayerhq.hu/mailman/listinfo/ffmpeg-devel}
1660

    
1661
It also helps quite a bit if you tell us what the patch does (for example
1662
'replaces lrint by lrintf'), and why (for example '*BSD isn't C99 compliant
1663
and has no lrint()')
1664

    
1665
Also please if you send several patches, send each patch as separate mail,
1666
do not attach several unrelated patches to the same mail.
1667

    
1668
@section patch submission checklist
1669

    
1670
@enumerate
1671
@item
1672
    Do the regression tests pass with the patch applied?
1673
@item
1674
    Is the patch a unified diff?
1675
@item
1676
    Is the patch against latest FFmpeg SVN?
1677
@item
1678
    Are you subscribed to ffmpeg-dev?
1679
    (the list is subscribers only due to spam)
1680
@item
1681
    Have you checked that the changes are minimal, so that the same cannot be
1682
    achieved with a smaller patch and/or simpler final code?
1683
@item
1684
    If the change is to speed critical code, did you benchmark it?
1685
@item
1686
    If you did any benchmarks, did you provide them in the mail?
1687
@item
1688
    Have you checked that the patch does not introduce buffer overflows or
1689
    other security issues?
1690
@item
1691
    Is the patch created from the root of the source tree, so it can be
1692
    applied with @code{patch -p0}?
1693
@item
1694
    Does the patch not mix functional and cosmetic changes?
1695
@item
1696
    Did you add tabs or trailing whitespace to the code? Both are forbidden.
1697
@item
1698
    Is the patch attached to the email you send?
1699
@item
1700
    Is the mime type of the patch correct? It should be text/x-diff or
1701
    text/x-patch or at least text/plain and not application/octet-stream.
1702
@item
1703
    If the patch fixes a bug, did you provide a verbose analysis of the bug?
1704
@item
1705
    If the patch fixes a bug, did you provide enough information, including
1706
    a sample, so the bug can be reproduced and the fix can be verified?
1707
@item
1708
    Did you provide a verbose summary about what the patch does change?
1709
@item
1710
    Did you provide a verbose explanation why it changes things like it does?
1711
@item
1712
    Did you provide a verbose summary of the user visible advantages and
1713
    disadvantages if the patch is applied?
1714
@item
1715
    Did you provide an example so we can verify the new feature added by the
1716
    patch easily?
1717
@item
1718
    If you added a new file, did you insert a license header? It should be
1719
    taken from FFmpeg, not randomly copied and pasted from somewhere else.
1720
@item
1721
    You should maintain alphabetical order in alphabetically ordered lists as
1722
    long as doing so does not break API/ABI compatibility.
1723
@item
1724
    Did you provide a suggestion for a clear commit log message?
1725
@end enumerate
1726

    
1727
@section Patch review process
1728

    
1729
All patches posted to ffmpeg-devel will be reviewed, unless they contain a
1730
clear note that the patch is not for SVN.
1731
Reviews and comments will be posted as replies to the patch on the
1732
mailing list. The patch submitter then has to take care of every comment,
1733
that can be by resubmitting a changed patch or by discussion. Resubmitted
1734
patches will themselves be reviewed like any other patch. If at some point
1735
a patch passes review with no comments then it is approved, that can for
1736
simple and small patches happen immediately while large patches will generally
1737
have to be changed and reviewed many times before they are approved.
1738
After a patch is approved it will be committed to the repository.
1739

    
1740
We will review all submitted patches, but sometimes we are quite busy so
1741
especially for large patches this can take several weeks.
1742

    
1743
When resubmitting patches, please do not make any significant changes
1744
not related to the comments received during review. Such patches will
1745
be rejected. Instead, submit  significant changes or new features as
1746
separate patches.
1747

    
1748
@section Regression tests
1749

    
1750
Before submitting a patch (or committing to the repository), you should at least
1751
test that you did not break anything.
1752

    
1753
The regression tests build a synthetic video stream and a synthetic
1754
audio stream. These are then encoded and decoded with all codecs or
1755
formats. The CRC (or MD5) of each generated file is recorded in a
1756
result file. A 'diff' is launched to compare the reference results and
1757
the result file.
1758

    
1759
The regression tests then go on to test the FFserver code with a
1760
limited set of streams. It is important that this step runs correctly
1761
as well.
1762

    
1763
Run 'make test' to test all the codecs and formats.
1764

    
1765
Run 'make fulltest' to test all the codecs, formats and FFserver.
1766

    
1767
[Of course, some patches may change the results of the regression tests. In
1768
this case, the reference results of the regression tests shall be modified
1769
accordingly].
1770

    
1771
@bye