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

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

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

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

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

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

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

    
719
@c man end
720

    
721
@ignore
722

    
723
@setfilename ffmpeg
724
@settitle FFmpeg video converter
725

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

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

    
734
@end ignore
735

    
736
@section Protocols
737

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

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

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

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

    
749
@chapter Tips
750

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

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

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

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

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

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

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

    
785
@end itemize
786

    
787

    
788
@chapter external libraries
789

    
790
FFmpeg can be hooked up with a number of external libraries to add support
791
for more formats.
792

    
793
@section AMR
794

    
795
AMR comes in two different flavors, WB and NB. FFmpeg can make use of the
796
AMR WB (floating-point mode) and the AMR NB (both floating-point and
797
fixed-point mode) reference decoders and encoders.
798

    
799
@itemize
800

    
801
@item For AMR WB floating-point download TS26.204 V5.1.0 from
802
@url{http://www.3gpp.org/ftp/Specs/archive/26_series/26.204/26204-510.zip}
803
and extract the source to @file{libavcodec/amrwb_float/}.
804

    
805
@item For AMR NB floating-point download TS26.104 REL-5 V5.1.0 from
806
@url{http://www.3gpp.org/ftp/Specs/archive/26_series/26.104/26104-510.zip}
807
and extract the source to @file{libavcodec/amr_float/}.
808
If you try this on Alpha, you may need to change @code{Word32} to
809
@code{int} in @file{amr/typedef.h}.
810

    
811
@item For AMR NB fixed-point download TS26.073 REL-5 V5.1.0 from
812
@url{http://www.3gpp.org/ftp/Specs/archive/26_series/26.073/26073-510.zip}
813
and extract the source to @file{libavcodec/amr}.
814
You must also add @code{-DMMS_IO} and remove @code{-pedantic-errors}
815
to/from @code{CFLAGS} in @file{libavcodec/amr/makefile}, i.e.
816
``@code{CFLAGS = -Wall -I. \$(CFLAGS_\$(MODE)) -D\$(VAD) -DMMS_IO}''.
817

    
818
@end itemize
819

    
820

    
821
@chapter Supported File Formats and Codecs
822

    
823
You can use the @code{-formats} option to have an exhaustive list.
824

    
825
@section File Formats
826

    
827
FFmpeg supports the following file formats through the @code{libavformat}
828
library:
829

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

    
906
@code{X} means that encoding (resp. decoding) is supported.
907

    
908
@section Image Formats
909

    
910
FFmpeg can read and write images for each frame of a video sequence. The
911
following image formats are supported:
912

    
913
@multitable @columnfractions .4 .1 .1 .4
914
@item Supported Image Format @tab Encoding @tab Decoding @tab Comments
915
@item PGM, PPM     @tab X @tab X
916
@item PAM          @tab X @tab X @tab PAM is a PNM extension with alpha support.
917
@item PGMYUV       @tab X @tab X @tab PGM with U and V components in YUV 4:2:0
918
@item JPEG         @tab X @tab X @tab Progressive JPEG is not supported.
919
@item .Y.U.V       @tab X @tab X @tab one raw file per component
920
@item animated GIF @tab X @tab X @tab Only uncompressed GIFs are generated.
921
@item PNG          @tab X @tab X @tab 2 bit and 4 bit/pixel not supported yet.
922
@item Targa        @tab   @tab X @tab Targa (.TGA) image format.
923
@item TIFF         @tab   @tab X @tab Only 24 bit/pixel images are supported.
924
@item SGI          @tab X @tab X @tab SGI RGB image format
925
@end multitable
926

    
927
@code{X} means that encoding (resp. decoding) is supported.
928

    
929
@section Video Codecs
930

    
931
@multitable @columnfractions .4 .1 .1 .4
932
@item Supported Codec @tab Encoding @tab Decoding @tab Comments
933
@item MPEG-1 video           @tab  X  @tab  X
934
@item MPEG-2 video           @tab  X  @tab  X
935
@item MPEG-4                 @tab  X  @tab  X
936
@item MSMPEG4 V1             @tab  X  @tab  X
937
@item MSMPEG4 V2             @tab  X  @tab  X
938
@item MSMPEG4 V3             @tab  X  @tab  X
939
@item WMV7                   @tab  X  @tab  X
940
@item WMV8                   @tab  X  @tab  X @tab not completely working
941
@item WMV9                   @tab     @tab  X @tab not completely working
942
@item VC1                    @tab     @tab  X
943
@item H.261                  @tab  X  @tab  X
944
@item H.263(+)               @tab  X  @tab  X @tab also known as RealVideo 1.0
945
@item H.264                  @tab     @tab  X
946
@item RealVideo 1.0          @tab  X  @tab  X
947
@item RealVideo 2.0          @tab  X  @tab  X
948
@item MJPEG                  @tab  X  @tab  X
949
@item lossless MJPEG         @tab  X  @tab  X
950
@item JPEG-LS                @tab  X  @tab  X @tab fourcc: MJLS, lossless and near-lossless is supported
951
@item Apple MJPEG-B          @tab     @tab  X
952
@item Sunplus MJPEG          @tab     @tab  X @tab fourcc: SP5X
953
@item DV                     @tab  X  @tab  X
954
@item HuffYUV                @tab  X  @tab  X
955
@item FFmpeg Video 1         @tab  X  @tab  X @tab experimental lossless codec (fourcc: FFV1)
956
@item FFmpeg Snow            @tab  X  @tab  X @tab experimental wavelet codec (fourcc: SNOW)
957
@item Asus v1                @tab  X  @tab  X @tab fourcc: ASV1
958
@item Asus v2                @tab  X  @tab  X @tab fourcc: ASV2
959
@item Creative YUV           @tab     @tab  X @tab fourcc: CYUV
960
@item Sorenson Video 1       @tab  X  @tab  X @tab fourcc: SVQ1
961
@item Sorenson Video 3       @tab     @tab  X @tab fourcc: SVQ3
962
@item On2 VP3                @tab     @tab  X @tab still experimental
963
@item On2 VP5                @tab     @tab  X @tab fourcc: VP50
964
@item On2 VP6                @tab     @tab  X @tab fourcc: VP60,VP61,VP62
965
@item Theora                 @tab  X  @tab  X @tab still experimental
966
@item Intel Indeo 3          @tab     @tab  X
967
@item FLV                    @tab  X  @tab  X @tab Sorenson H.263 used in Flash
968
@item Flash Screen Video     @tab  X  @tab  X @tab fourcc: FSV1
969
@item ATI VCR1               @tab     @tab  X @tab fourcc: VCR1
970
@item ATI VCR2               @tab     @tab  X @tab fourcc: VCR2
971
@item Cirrus Logic AccuPak   @tab     @tab  X @tab fourcc: CLJR
972
@item 4X Video               @tab     @tab  X @tab Used in certain computer games.
973
@item Sony Playstation MDEC  @tab     @tab  X
974
@item Id RoQ                 @tab     @tab  X @tab Used in Quake III, Jedi Knight 2, other computer games.
975
@item Xan/WC3                @tab     @tab  X @tab Used in Wing Commander III .MVE files.
976
@item Interplay Video        @tab     @tab  X @tab Used in Interplay .MVE files.
977
@item Apple Animation        @tab     @tab  X @tab fourcc: 'rle '
978
@item Apple Graphics         @tab     @tab  X @tab fourcc: 'smc '
979
@item Apple Video            @tab     @tab  X @tab fourcc: rpza
980
@item Apple QuickDraw        @tab     @tab  X @tab fourcc: qdrw
981
@item Cinepak                @tab     @tab  X
982
@item Microsoft RLE          @tab     @tab  X
983
@item Microsoft Video-1      @tab     @tab  X
984
@item Westwood VQA           @tab     @tab  X
985
@item Id Cinematic Video     @tab     @tab  X @tab Used in Quake II.
986
@item Planar RGB             @tab     @tab  X @tab fourcc: 8BPS
987
@item FLIC video             @tab     @tab  X
988
@item Duck TrueMotion v1     @tab     @tab  X @tab fourcc: DUCK
989
@item Duck TrueMotion v2     @tab     @tab  X @tab fourcc: TM20
990
@item VMD Video              @tab     @tab  X @tab Used in Sierra VMD files.
991
@item MSZH                   @tab     @tab  X @tab Part of LCL
992
@item ZLIB                   @tab  X  @tab  X @tab Part of LCL, encoder experimental
993
@item TechSmith Camtasia     @tab     @tab  X @tab fourcc: TSCC
994
@item IBM Ultimotion         @tab     @tab  X @tab fourcc: ULTI
995
@item Miro VideoXL           @tab     @tab  X @tab fourcc: VIXL
996
@item QPEG                   @tab     @tab  X @tab fourccs: QPEG, Q1.0, Q1.1
997
@item LOCO                   @tab     @tab  X @tab
998
@item Winnov WNV1            @tab     @tab  X @tab
999
@item Autodesk Animator Studio Codec  @tab     @tab  X @tab fourcc: AASC
1000
@item Fraps FPS1             @tab     @tab  X @tab
1001
@item CamStudio              @tab     @tab  X @tab fourcc: CSCD
1002
@item American Laser Games Video  @tab    @tab X @tab Used in games like Mad Dog McCree
1003
@item ZMBV                   @tab   X @tab  X @tab Encoder works only on PAL8
1004
@item AVS Video              @tab     @tab  X @tab Video encoding used by the Creature Shock game.
1005
@item Smacker Video          @tab     @tab  X @tab Video encoding used in Smacker.
1006
@item RTjpeg                 @tab     @tab  X @tab Video encoding used in NuppelVideo files.
1007
@item KMVC                   @tab     @tab  X @tab Codec used in Worms games.
1008
@item VMware Video           @tab     @tab  X @tab Codec used in videos captured by VMware.
1009
@item Cin Video              @tab     @tab  X @tab Codec used in Delphine Software games.
1010
@item Tiertex Seq Video      @tab     @tab  X @tab Codec used in DOS CDROM FlashBack game.
1011
@item DXA Video              @tab     @tab  X @tab Codec originally used in Feeble Files game.
1012
@end multitable
1013

    
1014
@code{X} means that encoding (resp. decoding) is supported.
1015

    
1016
@section Audio Codecs
1017

    
1018
@multitable @columnfractions .4 .1 .1 .1 .7
1019
@item Supported Codec @tab Encoding @tab Decoding @tab Comments
1020
@item MPEG audio layer 2     @tab  IX  @tab  IX
1021
@item MPEG audio layer 1/3   @tab IX   @tab  IX
1022
@tab MP3 encoding is supported through the external library LAME.
1023
@item AC3                    @tab  IX  @tab  IX
1024
@tab liba52 is used internally for decoding.
1025
@item Vorbis                 @tab  X   @tab  X
1026
@item WMA V1/V2              @tab X    @tab X
1027
@item AAC                    @tab X    @tab X
1028
@tab Supported through the external library libfaac/libfaad.
1029
@item Microsoft ADPCM        @tab X    @tab X
1030
@item MS IMA ADPCM           @tab X    @tab X
1031
@item QT IMA ADPCM           @tab      @tab X
1032
@item 4X IMA ADPCM           @tab      @tab X
1033
@item G.726  ADPCM           @tab X    @tab X
1034
@item Duck DK3 IMA ADPCM     @tab      @tab X
1035
@tab Used in some Sega Saturn console games.
1036
@item Duck DK4 IMA ADPCM     @tab      @tab X
1037
@tab Used in some Sega Saturn console games.
1038
@item Westwood Studios IMA ADPCM @tab      @tab X
1039
@tab Used in Westwood Studios games like Command and Conquer.
1040
@item SMJPEG IMA ADPCM       @tab      @tab X
1041
@tab Used in certain Loki game ports.
1042
@item CD-ROM XA ADPCM        @tab      @tab X
1043
@item CRI ADX ADPCM          @tab X    @tab X
1044
@tab Used in Sega Dreamcast games.
1045
@item Electronic Arts ADPCM  @tab      @tab X
1046
@tab Used in various EA titles.
1047
@item Creative ADPCM         @tab      @tab X
1048
@tab 16 -> 4, 8 -> 4, 8 -> 3, 8 -> 2
1049
@item RA144                  @tab      @tab X
1050
@tab Real 14400 bit/s codec
1051
@item RA288                  @tab      @tab X
1052
@tab Real 28800 bit/s codec
1053
@item RADnet                 @tab X    @tab IX
1054
@tab Real low bitrate AC3 codec, liba52 is used for decoding.
1055
@item AMR-NB                 @tab X    @tab X
1056
@tab Supported through an external library.
1057
@item AMR-WB                 @tab X    @tab X
1058
@tab Supported through an external library.
1059
@item DV audio               @tab      @tab X
1060
@item Id RoQ DPCM            @tab      @tab X
1061
@tab Used in Quake III, Jedi Knight 2, other computer games.
1062
@item Interplay MVE DPCM     @tab      @tab X
1063
@tab Used in various Interplay computer games.
1064
@item Xan DPCM               @tab      @tab X
1065
@tab Used in Origin's Wing Commander IV AVI files.
1066
@item Sierra Online DPCM     @tab      @tab X
1067
@tab Used in Sierra Online game audio files.
1068
@item Apple MACE 3           @tab      @tab X
1069
@item Apple MACE 6           @tab      @tab X
1070
@item FLAC lossless audio    @tab      @tab X
1071
@item Shorten lossless audio @tab      @tab X
1072
@item Apple lossless audio   @tab      @tab X
1073
@tab QuickTime fourcc 'alac'
1074
@item FFmpeg Sonic           @tab X    @tab X
1075
@tab experimental lossy/lossless codec
1076
@item Qdesign QDM2           @tab      @tab X
1077
@tab there are still some distortions
1078
@item Real COOK              @tab      @tab X
1079
@tab All versions except 5.1 are supported
1080
@item DSP Group TrueSpeech   @tab      @tab X
1081
@item True Audio (TTA)       @tab      @tab X
1082
@item Smacker Audio          @tab      @tab X
1083
@item WavPack Audio          @tab      @tab X
1084
@item Cin Audio              @tab      @tab X
1085
@tab Codec used in Delphine Software games.
1086
@item Intel Music Coder      @tab      @tab X
1087
@item Musepack               @tab      @tab X
1088
@tab Only SV7 is supported
1089
@item DT$ Coherent Audio     @tab      @tab X
1090
@end multitable
1091

    
1092
@code{X} means that encoding (resp. decoding) is supported.
1093

    
1094
@code{I} means that an integer-only version is available, too (ensures high
1095
performance on systems without hardware floating point support).
1096

    
1097
@chapter Platform Specific information
1098

    
1099
@section BSD
1100

    
1101
BSD make will not build FFmpeg, you need to install and use GNU Make
1102
(@file{gmake}).
1103

    
1104
@section Windows
1105

    
1106
To get help and instructions for using FFmpeg under Windows, check out
1107
the FFmpeg Windows Help Forum at
1108
@url{http://arrozcru.no-ip.org/ffmpeg/}.
1109

    
1110
@subsection Native Windows compilation
1111

    
1112
@itemize
1113
@item Install the current versions of MSYS and MinGW from
1114
@url{http://www.mingw.org/}. You can find detailed installation
1115
instructions in the download section and the FAQ.
1116

    
1117
NOTE: Use at least bash 3.1. Older versions are known to be failing on the
1118
configure script.
1119

    
1120
@item If you want to test the FFplay, also download
1121
the MinGW development library of SDL 1.2.x
1122
(@file{SDL-devel-1.2.x-mingw32.tar.gz}) from
1123
@url{http://www.libsdl.org}. Unpack it in a temporary directory, and
1124
unpack the archive @file{i386-mingw32msvc.tar.gz} in the MinGW tool
1125
directory. Edit the @file{sdl-config} script so that it gives the
1126
correct SDL directory when invoked.
1127

    
1128
@item Extract the current version of FFmpeg.
1129

    
1130
@item Start the MSYS shell (file @file{msys.bat}).
1131

    
1132
@item Change to the FFmpeg directory and follow
1133
 the instructions of how to compile FFmpeg (file
1134
@file{INSTALL}). Usually, launching @file{./configure} and @file{make}
1135
suffices. If you have problems using SDL, verify that
1136
@file{sdl-config} can be launched from the MSYS command line.
1137

    
1138
@item You can install FFmpeg in @file{Program Files/FFmpeg} by typing
1139
@file{make install}. Don't forget to copy @file{SDL.dll} to the place
1140
you launch @file{ffplay} from.
1141

    
1142
@end itemize
1143

    
1144
Notes:
1145
@itemize
1146

    
1147
@item The target @file{make wininstaller} can be used to create a
1148
Nullsoft based Windows installer for FFmpeg and FFplay. @file{SDL.dll}
1149
must be copied to the FFmpeg directory in order to build the
1150
installer.
1151

    
1152
@item By using @code{./configure --enable-shared} when configuring FFmpeg,
1153
you can build @file{avcodec.dll} and @file{avformat.dll}. With
1154
@code{make install} you install the FFmpeg DLLs and the associated
1155
headers in @file{Program Files/FFmpeg}.
1156

    
1157
@item Visual C++ compatibility: If you used @code{./configure --enable-shared}
1158
when configuring FFmpeg, FFmpeg tries to use the Microsoft Visual
1159
C++ @code{lib} tool to build @code{avcodec.lib} and
1160
@code{avformat.lib}. With these libraries you can link your Visual C++
1161
code directly with the FFmpeg DLLs (see below).
1162

    
1163
@end itemize
1164

    
1165
@subsection Visual C++ compatibility
1166

    
1167
FFmpeg will not compile under Visual C++ -- and it has too many
1168
dependencies on the GCC compiler to make a port viable. However,
1169
if you want to use the FFmpeg libraries in your own applications,
1170
you can still compile those applications using Visual C++. An
1171
important restriction to this is that you have to use the
1172
dynamically linked versions of the FFmpeg libraries (i.e. the
1173
DLLs), and you have to make sure that Visual-C++-compatible
1174
import libraries are created during the FFmpeg build process.
1175

    
1176
This description of how to use the FFmpeg libraries with Visual C++ is
1177
based on Visual C++ 2005 Express Edition Beta 2. If you have a different
1178
version, you might have to modify the procedures slightly.
1179

    
1180
Here are the step-by-step instructions for building the FFmpeg libraries
1181
so they can be used with Visual C++:
1182

    
1183
@enumerate
1184

    
1185
@item Install Visual C++ (if you haven't done so already).
1186

    
1187
@item Install MinGW and MSYS as described above.
1188

    
1189
@item Add a call to @file{vcvars32.bat} (which sets up the environment
1190
variables for the Visual C++ tools) as the first line of
1191
@file{msys.bat}. The standard location for @file{vcvars32.bat} is
1192
@file{C:\Program Files\Microsoft Visual Studio 8\VC\bin\vcvars32.bat},
1193
and the standard location for @file{msys.bat} is
1194
@file{C:\msys\1.0\msys.bat}. If this corresponds to your setup, add the
1195
following line as the first line of @file{msys.bat}:
1196

    
1197
@code{call "C:\Program Files\Microsoft Visual Studio 8\VC\bin\vcvars32.bat"}
1198

    
1199
@item Start the MSYS shell (file @file{msys.bat}) and type @code{link.exe}.
1200
If you get a help message with the command line options of @code{link.exe},
1201
this means your environment variables are set up correctly, the
1202
Microsoft linker is on the path and will be used by FFmpeg to
1203
create Visual-C++-compatible import libraries.
1204

    
1205
@item Extract the current version of FFmpeg and change to the FFmpeg directory.
1206

    
1207
@item Type the command
1208
@code{./configure --enable-shared --disable-static --enable-memalign-hack}
1209
to configure and, if that didn't produce any errors,
1210
type @code{make} to build FFmpeg.
1211

    
1212
@item The subdirectories @file{libavformat}, @file{libavcodec}, and
1213
@file{libavutil} should now contain the files @file{avformat.dll},
1214
@file{avformat.lib}, @file{avcodec.dll}, @file{avcodec.lib},
1215
@file{avutil.dll}, and @file{avutil.lib}, respectively. Copy the three
1216
DLLs to your System32 directory (typically @file{C:\Windows\System32}).
1217

    
1218
@end enumerate
1219

    
1220
And here is how to use these libraries with Visual C++:
1221

    
1222
@enumerate
1223

    
1224
@item Create a new console application ("File / New / Project") and then
1225
select "Win32 Console Application". On the appropriate page of the
1226
Application Wizard, uncheck the "Precompiled headers" option.
1227

    
1228
@item Write the source code for your application, or, for testing, just
1229
copy the code from an existing sample application into the source file
1230
that Visual C++ has already created for you. (Note that your source
1231
filehas to have a @code{.cpp} extension; otherwise, Visual C++ won't
1232
compile the FFmpeg headers correctly because in C mode, it doesn't
1233
recognize the @code{inline} keyword.)  For example, you can copy
1234
@file{output_example.c} from the FFmpeg distribution (but you will
1235
have to make minor modifications so the code will compile under
1236
C++, see below).
1237

    
1238
@item Open the "Project / Properties" dialog box. In the "Configuration"
1239
combo box, select "All Configurations" so that the changes you make will
1240
affect both debug and release builds. In the tree view on the left hand
1241
side, select "C/C++ / General", then edit the "Additional Include
1242
Directories" setting to contain the complete paths to the
1243
@file{libavformat}, @file{libavcodec}, and @file{libavutil}
1244
subdirectories of your FFmpeg directory. Note that the directories have
1245
to be separated using semicolons. Now select "Linker / General" from the
1246
tree view and edit the "Additional Library Directories" setting to
1247
contain the same three directories.
1248

    
1249
@item Still in the "Project / Properties" dialog box, select "Linker / Input"
1250
from the tree view, then add the files @file{avformat.lib},
1251
@file{avcodec.lib}, and @file{avutil.lib} to the end of the "Additional
1252
Dependencies". Note that the names of the libraries have to be separated
1253
using spaces.
1254

    
1255
@item Now, select "C/C++ / Code Generation" from the tree view. Select
1256
"Debug" in the "Configuration" combo box. Make sure that "Runtime
1257
Library" is set to "Multi-threaded Debug DLL". Then, select "Release" in
1258
the "Configuration" combo box and make sure that "Runtime Library" is
1259
set to "Multi-threaded DLL".
1260

    
1261
@item Click "OK" to close the "Project / Properties" dialog box and build
1262
the application. Hopefully, it should compile and run cleanly. If you
1263
used @file{output_example.c} as your sample application, you will get a
1264
few compiler errors, but they are easy to fix. The first type of error
1265
occurs because Visual C++ doesn't allow an @code{int} to be converted to
1266
an @code{enum} without a cast. To solve the problem, insert the required
1267
casts (this error occurs once for a @code{CodecID} and once for a
1268
@code{CodecType}).  The second type of error occurs because C++ requires
1269
the return value of @code{malloc} to be cast to the exact type of the
1270
pointer it is being assigned to. Visual C++ will complain that, for
1271
example, @code{(void *)} is being assigned to @code{(uint8_t *)} without
1272
an explicit cast. So insert an explicit cast in these places to silence
1273
the compiler. The third type of error occurs because the @code{snprintf}
1274
library function is called @code{_snprintf} under Visual C++.  So just
1275
add an underscore to fix the problem. With these changes,
1276
@file{output_example.c} should compile under Visual C++, and the
1277
resulting executable should produce valid video files.
1278

    
1279
@end enumerate
1280

    
1281
@subsection Cross compilation for Windows with Linux
1282

    
1283
You must use the MinGW cross compilation tools available at
1284
@url{http://www.mingw.org/}.
1285

    
1286
Then configure FFmpeg with the following options:
1287
@example
1288
./configure --target-os=mingw32 --cross-prefix=i386-mingw32msvc-
1289
@end example
1290
(you can change the cross-prefix according to the prefix chosen for the
1291
MinGW tools).
1292

    
1293
Then you can easily test FFmpeg with Wine
1294
(@url{http://www.winehq.com/}).
1295

    
1296
@subsection Compilation under Cygwin
1297

    
1298
Cygwin works very much like Unix.
1299

    
1300
Just install your Cygwin with all the "Base" packages, plus the
1301
following "Devel" ones:
1302
@example
1303
binutils, gcc-core, make, subversion
1304
@end example
1305

    
1306
Do not install binutils-20060709-1 (they are buggy on shared builds);
1307
use binutils-20050610-1 instead.
1308

    
1309
Then run
1310

    
1311
@example
1312
./configure --enable-static --disable-shared
1313
@end example
1314

    
1315
to make a static build or
1316

    
1317
@example
1318
./configure --enable-shared --disable-static
1319
@end example
1320

    
1321
to build shared libraries.
1322

    
1323
If you want to build FFmpeg with additional libraries, download Cygwin
1324
"Devel" packages for Ogg and Vorbis from any Cygwin packages repository
1325
and/or SDL, xvid, faac, faad2 packages from Cygwin Ports,
1326
(@url{http://cygwinports.dotsrc.org/}).
1327

    
1328
@subsection Crosscompilation for Windows under Cygwin
1329

    
1330
With Cygwin you can create Windows binaries that don't need the cygwin1.dll.
1331

    
1332
Just install your Cygwin as explained before, plus these additional
1333
"Devel" packages:
1334
@example
1335
gcc-mingw-core, mingw-runtime, mingw-zlib
1336
@end example
1337

    
1338
and add some special flags to your configure invocation.
1339

    
1340
For a static build run
1341
@example
1342
./configure --target-os=mingw32 --enable-memalign-hack --enable-static --disable-shared --extra-cflags=-mno-cygwin --extra-libs=-mno-cygwin
1343
@end example
1344

    
1345
and for a build with shared libraries
1346
@example
1347
./configure --target-os=mingw32 --enable-memalign-hack --enable-shared --disable-static --extra-cflags=-mno-cygwin --extra-libs=-mno-cygwin
1348
@end example
1349

    
1350
@section BeOS
1351

    
1352
The configure script should guess the configuration itself.
1353
Networking support is currently not finished.
1354
errno issues fixed by Andrew Bachmann.
1355

    
1356
Old stuff:
1357

    
1358
Fran├žois Revol - revol at free dot fr - April 2002
1359

    
1360
The configure script should guess the configuration itself,
1361
however I still didn't test building on the net_server version of BeOS.
1362

    
1363
FFserver is broken (needs poll() implementation).
1364

    
1365
There are still issues with errno codes, which are negative in BeOS, and
1366
that FFmpeg negates when returning. This ends up turning errors into
1367
valid results, then crashes.
1368
(To be fixed)
1369

    
1370
@chapter Developers Guide
1371

    
1372
@section API
1373
@itemize @bullet
1374
@item libavcodec is the library containing the codecs (both encoding and
1375
decoding). Look at @file{libavcodec/apiexample.c} to see how to use it.
1376

    
1377
@item libavformat is the library containing the file format handling (mux and
1378
demux code for several formats). Look at @file{ffplay.c} to use it in a
1379
player. See @file{output_example.c} to use it to generate audio or video
1380
streams.
1381

    
1382
@end itemize
1383

    
1384
@section Integrating libavcodec or libavformat in your program
1385

    
1386
You can integrate all the source code of the libraries to link them
1387
statically to avoid any version problem. All you need is to provide a
1388
'config.mak' and a 'config.h' in the parent directory. See the defines
1389
generated by ./configure to understand what is needed.
1390

    
1391
You can use libavcodec or libavformat in your commercial program, but
1392
@emph{any patch you make must be published}. The best way to proceed is
1393
to send your patches to the FFmpeg mailing list.
1394

    
1395
@node Coding Rules
1396
@section Coding Rules
1397

    
1398
FFmpeg is programmed in the ISO C90 language with a few additional
1399
features from ISO C99, namely:
1400
@itemize @bullet
1401
@item
1402
the @samp{inline} keyword;
1403
@item
1404
@samp{//} comments;
1405
@item
1406
designated struct initializers (@samp{struct s x = @{ .i = 17 @};})
1407
@item
1408
compound literals (@samp{x = (struct s) @{ 17, 23 @};})
1409
@end itemize
1410

    
1411
These features are supported by all compilers we care about, so we won't
1412
accept patches to remove their use unless they absolutely don't impair
1413
clarity and performance.
1414

    
1415
All code must compile with GCC 2.95 and GCC 3.3. Currently, FFmpeg also
1416
compiles with several other compilers, such as the Compaq ccc compiler
1417
or Sun Studio 9, and we would like to keep it that way unless it would
1418
be exceedingly involved. To ensure compatibility, please don't use any
1419
additional C99 features or GCC extensions. Especially watch out for:
1420
@itemize @bullet
1421
@item
1422
mixing statements and declarations;
1423
@item
1424
@samp{long long} (use @samp{int64_t} instead);
1425
@item
1426
@samp{__attribute__} not protected by @samp{#ifdef __GNUC__} or similar;
1427
@item
1428
GCC statement expressions (@samp{(x = (@{ int y = 4; y; @})}).
1429
@end itemize
1430

    
1431
Indent size is 4.
1432
The presentation is the one specified by 'indent -i4 -kr -nut'.
1433
The TAB character is forbidden outside of Makefiles as is any
1434
form of trailing whitespace. Commits containing either will be
1435
rejected by the Subversion repository.
1436

    
1437
Main priority in FFmpeg is simplicity and small code size (=less
1438
bugs).
1439

    
1440
Comments: Use the JavaDoc/Doxygen
1441
format (see examples below) so that code documentation
1442
can be generated automatically. All nontrivial functions should have a comment
1443
above them explaining what the function does, even if it's just one sentence.
1444
All structures and their member variables should be documented, too.
1445
@example
1446
/**
1447
 * @@file mpeg.c
1448
 * MPEG codec.
1449
 * @@author ...
1450
 */
1451

    
1452
/**
1453
 * Summary sentence.
1454
 * more text ...
1455
 * ...
1456
 */
1457
typedef struct Foobar@{
1458
    int var1; /**< var1 description */
1459
    int var2; ///< var2 description
1460
    /** var3 description */
1461
    int var3;
1462
@} Foobar;
1463

    
1464
/**
1465
 * Summary sentence.
1466
 * more text ...
1467
 * ...
1468
 * @@param my_parameter description of my_parameter
1469
 * @@return return value description
1470
 */
1471
int myfunc(int my_parameter)
1472
...
1473
@end example
1474

    
1475
fprintf and printf are forbidden in libavformat and libavcodec,
1476
please use av_log() instead.
1477

    
1478
@section Development Policy
1479

    
1480
@enumerate
1481
@item
1482
   You must not commit code which breaks FFmpeg! (Meaning unfinished but
1483
   enabled code which breaks compilation or compiles but does not work or
1484
   breaks the regression tests)
1485
   You can commit unfinished stuff (for testing etc), but it must be disabled
1486
   (#ifdef etc) by default so it does not interfere with other developers'
1487
   work.
1488
@item
1489
   You don't have to over-test things. If it works for you, and you think it
1490
   should work for others, then commit. If your code has problems
1491
   (portability, triggers compiler bugs, unusual environment etc) they will be
1492
   reported and eventually fixed.
1493
@item
1494
   Do not commit unrelated changes together, split them into self-contained
1495
   pieces.
1496
@item
1497
   Do not change behavior of the program (renaming options etc) without
1498
   first discussing it on the ffmpeg-devel mailing list. Do not remove
1499
   functionality from the code. Just improve!
1500

    
1501
   Note: Redundant code can be removed.
1502
@item
1503
   Do not commit changes to the build system (Makefiles, configure script)
1504
   which change behavior, defaults etc, without asking first. The same
1505
   applies to compiler warning fixes, trivial looking fixes and to code
1506
   maintained by other developers. We usually have a reason for doing things
1507
   the way we do. Send your changes as patches to the ffmpeg-devel mailing
1508
   list, and if the code maintainers say OK, you may commit. This does not
1509
   apply to files you wrote and/or maintain.
1510
@item
1511
   We refuse source indentation and other cosmetic changes if they are mixed
1512
   with functional changes, such commits will be rejected and removed. Every
1513
   developer has his own indentation style, you should not change it. Of course
1514
   if you (re)write something, you can use your own style, even though we would
1515
   prefer if the indentation throughout FFmpeg was consistent (Many projects
1516
   force a given indentation style - we don't.). If you really need to make
1517
   indentation changes (try to avoid this), separate them strictly from real
1518
   changes.
1519

    
1520
   NOTE: If you had to put if()@{ .. @} over a large (> 5 lines) chunk of code,
1521
   then either do NOT change the indentation of the inner part within (don't
1522
   move it to the right)! or do so in a separate commit
1523
@item
1524
   Always fill out the commit log message. Describe in a few lines what you
1525
   changed and why. You can refer to mailing list postings if you fix a
1526
   particular bug. Comments such as "fixed!" or "Changed it." are unacceptable.
1527
@item
1528
   If you apply a patch by someone else, include the name and email address in
1529
   the log message. Since the ffmpeg-cvslog mailing list is publicly
1530
   archived you should add some SPAM protection to the email address. Send an
1531
   answer to ffmpeg-devel (or wherever you got the patch from) saying that
1532
   you applied the patch.
1533
@item
1534
    Do NOT commit to code actively maintained by others without permission.
1535
    Send a patch to ffmpeg-devel instead. If noone answers within a reasonable
1536
    timeframe (12h for build failures and security fixes, 3 days small changes,
1537
    1 week for big patches) then commit your patch if you think it's OK.
1538
    Also note, the maintainer can simply ask for more time to review!
1539
@item
1540
    Subscribe to the ffmpeg-cvslog mailing list. The diffs of all commits
1541
    are sent there and reviewed by all the other developers. Bugs and possible
1542
    improvements or general questions regarding commits are discussed there. We
1543
    expect you to react if problems with your code are uncovered.
1544
@item
1545
    Update the documentation if you change behavior or add features. If you are
1546
    unsure how best to do this, send a patch to ffmpeg-devel, the documentation
1547
    maintainer(s) will review and commit your stuff.
1548
@item
1549
    Never write to unallocated memory, never write over the end of arrays,
1550
    always check values read from some untrusted source before using them
1551
    as array index or other risky things.
1552
@item
1553
    Remember to check if you need to bump versions for the specific libav
1554
    parts (libavutil, libavcodec, libavformat) you are changing. You need
1555
    to change the version integer and the version string.
1556
    Incrementing the first component means no backward compatibility to
1557
    previous versions (e.g. removal of a function from the public API).
1558
    Incrementing the second component means backward compatible change
1559
    (e.g. addition of a function to the public API).
1560
    Incrementing the third component means a noteworthy binary compatible
1561
    change (e.g. encoder bug fix that matters for the decoder).
1562
@item
1563
    If you add a new codec, remember to update the changelog, add it to
1564
    the supported codecs table in the documentation and bump the second
1565
    component of the @file{libavcodec} version number appropriately. If
1566
    it has a fourcc, add it to @file{libavformat/avienc.c}, even if it
1567
    is only a decoder.
1568
@end enumerate
1569

    
1570
We think our rules are not too hard. If you have comments, contact us.
1571

    
1572
Note, these rules are mostly borrowed from the MPlayer project.
1573

    
1574
@section Submitting patches
1575

    
1576
First, (@pxref{Coding Rules}) above if you didn't yet.
1577

    
1578
When you submit your patch, try to send a unified diff (diff '-up'
1579
option). I cannot read other diffs :-)
1580

    
1581
Also please do not submit patches which contain several unrelated changes.
1582
Split them into individual self-contained patches; this makes reviewing
1583
them much easier.
1584

    
1585
Run the regression tests before submitting a patch so that you can
1586
verify that there are no big problems.
1587

    
1588
Patches should be posted as base64 encoded attachments (or any other
1589
encoding which ensures that the patch won't be trashed during
1590
transmission) to the ffmpeg-devel mailing list, see
1591
@url{http://lists.mplayerhq.hu/mailman/listinfo/ffmpeg-devel}
1592

    
1593
It also helps quite a bit if you tell us what the patch does (for example
1594
'replaces lrint by lrintf'), and why (for example '*BSD isn't C99 compliant
1595
and has no lrint()')
1596

    
1597
@section Patch review process
1598

    
1599
All patches posted to ffmpeg-devel will be reviewed, unless they contain a
1600
clear note that the patch is not for SVN.
1601
Reviews and comments will be posted as replies to the patch on the
1602
mailinglist. The patch submitter then has to take care of every comment,
1603
that can be by resubmitting a changed patch or by disscussion. Resubmitted
1604
patches will themselfs be reviewed like any other patch. If at some point
1605
a patch passes review with no comments then it is approved, that can for
1606
simple and small patches happen immedeatly while large patches will generally
1607
have to be changed and reviewed many times before they are approved.
1608
After a patch is approved it will be applied to ffmpeg svn
1609

    
1610
We will review all submitted patches, but sometimes we are quite busy so
1611
especially for large patches this can take several weeks.
1612

    
1613
When resubmitting patches, please do not make any significant changes
1614
unrelated to the comments such patches will be rejected, Instead submit
1615
such significant changes or new features as seperate patches.
1616

    
1617
@section Regression tests
1618

    
1619
Before submitting a patch (or committing to the repository), you should at least
1620
test that you did not break anything.
1621

    
1622
The regression tests build a synthetic video stream and a synthetic
1623
audio stream. These are then encoded and decoded with all codecs or
1624
formats. The CRC (or MD5) of each generated file is recorded in a
1625
result file. A 'diff' is launched to compare the reference results and
1626
the result file.
1627

    
1628
The regression tests then go on to test the FFserver code with a
1629
limited set of streams. It is important that this step runs correctly
1630
as well.
1631

    
1632
Run 'make test' to test all the codecs and formats.
1633

    
1634
Run 'make fulltest' to test all the codecs, formats and FFserver.
1635

    
1636
[Of course, some patches may change the results of the regression tests. In
1637
this case, the reference results of the regression tests shall be modified
1638
accordingly].
1639

    
1640
@bye