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patch by Alexis Ballier: [alexis ballier gmail com] original thread: [FFmpeg-devel] [Patch] QT RLE encoder, bis date: 06/24/2007 03:56 PM Originally committed as revision 9452 to svn://svn.ffmpeg.org/ffmpeg/trunk
1791 lines
60 KiB
Plaintext
1791 lines
60 KiB
Plaintext
\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 libmp3lame -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-libmp3lame} 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. Use 'list' as parameter to show all the supported
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pixel formats.
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@item -sws_flags flags
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Set SwScaler flags (only available when compiled with SwScaler support).
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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
|
|
@table @samp
|
|
@item 0
|
|
FF_MB_DECISION_SIMPLE: Use mb_cmp (cannot change it yet in FFmpeg).
|
|
@item 1
|
|
FF_MB_DECISION_BITS: Choose the one which needs the fewest bits.
|
|
@item 2
|
|
FF_MB_DECISION_RD: rate distortion
|
|
@end table
|
|
|
|
@item -4mv
|
|
Use four motion vector by macroblock (MPEG-4 only).
|
|
@item -part
|
|
Use data partitioning (MPEG-4 only).
|
|
@item -bug param
|
|
Work around encoder bugs that are not auto-detected.
|
|
@item -strict strictness
|
|
How strictly to follow the standards.
|
|
@item -aic
|
|
Enable Advanced intra coding (h263+).
|
|
@item -umv
|
|
Enable Unlimited Motion Vector (h263+)
|
|
|
|
@item -deinterlace
|
|
Deinterlace pictures.
|
|
@item -ilme
|
|
Force interlacing support in encoder (MPEG-2 and MPEG-4 only).
|
|
Use this option if your input file is interlaced and you want
|
|
to keep the interlaced format for minimum losses.
|
|
The alternative is to deinterlace the input stream with
|
|
@option{-deinterlace}, but deinterlacing introduces losses.
|
|
@item -psnr
|
|
Calculate PSNR of compressed frames.
|
|
@item -vstats
|
|
Dump video coding statistics to @file{vstats_HHMMSS.log}.
|
|
@item -vstats_file file
|
|
Dump video coding statistics to @var{file}.
|
|
@item -vhook module
|
|
Insert video processing @var{module}. @var{module} contains the module
|
|
name and its parameters separated by spaces.
|
|
@item -top n
|
|
top=1/bottom=0/auto=-1 field first
|
|
@item -dc precision
|
|
Intra_dc_precision.
|
|
@item -vtag fourcc/tag
|
|
Force video tag/fourcc.
|
|
@item -qphist
|
|
Show QP histogram.
|
|
@item -vbsf bitstream filter
|
|
Bitstream filters available are "dump_extra", "remove_extra", "noise".
|
|
@end table
|
|
|
|
@section Audio Options
|
|
|
|
@table @option
|
|
@item -aframes number
|
|
Set the number of audio frames to record.
|
|
@item -ar freq
|
|
Set the audio sampling frequency (default = 44100 Hz).
|
|
@item -ab bitrate
|
|
Set the audio bitrate in bit/s (default = 64k).
|
|
@item -ac channels
|
|
Set the number of audio channels (default = 1).
|
|
@item -an
|
|
Disable audio recording.
|
|
@item -acodec codec
|
|
Force audio codec to @var{codec}. Use the @code{copy} special value to
|
|
specify that the raw codec data must be copied as is.
|
|
@item -newaudio
|
|
Add a new audio track to the output file. If you want to specify parameters,
|
|
do so before @code{-newaudio} (@code{-acodec}, @code{-ab}, etc..).
|
|
|
|
Mapping will be done automatically, if the number of output streams is equal to
|
|
the number of input streams, else it will pick the first one that matches. You
|
|
can override the mapping using @code{-map} as usual.
|
|
|
|
Example:
|
|
@example
|
|
ffmpeg -i file.mpg -vcodec copy -acodec ac3 -ab 384k test.mpg -acodec mp2 -ab 192k -newaudio
|
|
@end example
|
|
@item -alang code
|
|
Set the ISO 639 language code (3 letters) of the current audio stream.
|
|
@end table
|
|
|
|
@section Advanced Audio options:
|
|
|
|
@table @option
|
|
@item -atag fourcc/tag
|
|
Force audio tag/fourcc.
|
|
@item -absf bitstream filter
|
|
Bitstream filters available are "dump_extra", "remove_extra", "noise", "mp3comp", "mp3decomp".
|
|
@end table
|
|
|
|
@section Subtitle options:
|
|
|
|
@table @option
|
|
@item -scodec codec
|
|
Force subtitle codec ('copy' to copy stream).
|
|
@item -newsubtitle
|
|
Add a new subtitle stream to the current output stream.
|
|
@item -slang code
|
|
Set the ISO 639 language code (3 letters) of the current subtitle stream.
|
|
@end table
|
|
|
|
@section Audio/Video grab options
|
|
|
|
@table @option
|
|
@item -vc channel
|
|
Set video grab channel (DV1394 only).
|
|
@item -tvstd standard
|
|
Set television standard (NTSC, PAL (SECAM)).
|
|
@item -isync
|
|
Synchronize read on input.
|
|
@end table
|
|
|
|
@section Advanced options
|
|
|
|
@table @option
|
|
@item -map input stream id[:input stream id]
|
|
Set stream mapping from input streams to output streams.
|
|
Just enumerate the input streams in the order you want them in the output.
|
|
[input stream id] sets the (input) stream to sync against.
|
|
@item -map_meta_data outfile:infile
|
|
Set meta data information of outfile from infile.
|
|
@item -debug
|
|
Print specific debug info.
|
|
@item -benchmark
|
|
Add timings for benchmarking.
|
|
@item -dump
|
|
Dump each input packet.
|
|
@item -hex
|
|
When dumping packets, also dump the payload.
|
|
@item -bitexact
|
|
Only use bit exact algorithms (for codec testing).
|
|
@item -ps size
|
|
Set packet size in bits.
|
|
@item -re
|
|
Read input at native frame rate. Mainly used to simulate a grab device.
|
|
@item -loop_input
|
|
Loop over the input stream. Currently it works only for image
|
|
streams. This option is used for automatic FFserver testing.
|
|
@item -loop_output number_of_times
|
|
Repeatedly loop output for formats that support looping such as animated GIF
|
|
(0 will loop the output infinitely).
|
|
@item -threads count
|
|
Thread count.
|
|
@item -vsync parameter
|
|
Video sync method. Video will be stretched/squeezed to match the timestamps,
|
|
it is done by duplicating and dropping frames. With -map you can select from
|
|
which stream the timestamps should be taken. You can leave either video or
|
|
audio unchanged and sync the remaining stream(s) to the unchanged one.
|
|
@item -async samples_per_second
|
|
Audio sync method. "Stretches/squeezes" the audio stream to match the timestamps,
|
|
the parameter is the maximum samples per second by which the audio is changed.
|
|
-async 1 is a special case where only the start of the audio stream is corrected
|
|
without any later correction.
|
|
@item -copyts
|
|
Copy timestamps from input to output.
|
|
@item -shortest
|
|
Finish encoding when the shortest input stream ends.
|
|
@item -dts_delta_threshold
|
|
Timestamp discontinuity delta threshold.
|
|
@item -muxdelay seconds
|
|
Set the maximum demux-decode delay.
|
|
@item -muxpreload seconds
|
|
Set the initial demux-decode delay.
|
|
@end table
|
|
|
|
@node FFmpeg formula evaluator
|
|
@section FFmpeg formula evaluator
|
|
|
|
When evaluating a rate control string, FFmpeg uses an internal formula
|
|
evaluator.
|
|
|
|
The following binary operators are available: @code{+}, @code{-},
|
|
@code{*}, @code{/}, @code{^}.
|
|
|
|
The following unary operators are available: @code{+}, @code{-},
|
|
@code{(...)}.
|
|
|
|
The following functions are available:
|
|
@table @var
|
|
@item sinh(x)
|
|
@item cosh(x)
|
|
@item tanh(x)
|
|
@item sin(x)
|
|
@item cos(x)
|
|
@item tan(x)
|
|
@item exp(x)
|
|
@item log(x)
|
|
@item squish(x)
|
|
@item gauss(x)
|
|
@item abs(x)
|
|
@item max(x, y)
|
|
@item min(x, y)
|
|
@item gt(x, y)
|
|
@item lt(x, y)
|
|
@item eq(x, y)
|
|
@item bits2qp(bits)
|
|
@item qp2bits(qp)
|
|
@end table
|
|
|
|
The following constants are available:
|
|
@table @var
|
|
@item PI
|
|
@item E
|
|
@item iTex
|
|
@item pTex
|
|
@item tex
|
|
@item mv
|
|
@item fCode
|
|
@item iCount
|
|
@item mcVar
|
|
@item var
|
|
@item isI
|
|
@item isP
|
|
@item isB
|
|
@item avgQP
|
|
@item qComp
|
|
@item avgIITex
|
|
@item avgPITex
|
|
@item avgPPTex
|
|
@item avgBPTex
|
|
@item avgTex
|
|
@end table
|
|
|
|
@c man end
|
|
|
|
@ignore
|
|
|
|
@setfilename ffmpeg
|
|
@settitle FFmpeg video converter
|
|
|
|
@c man begin SEEALSO
|
|
ffserver(1), ffplay(1) and the HTML documentation of @file{ffmpeg}.
|
|
@c man end
|
|
|
|
@c man begin AUTHOR
|
|
Fabrice Bellard
|
|
@c man end
|
|
|
|
@end ignore
|
|
|
|
@section Protocols
|
|
|
|
The filename can be @file{-} to read from standard input or to write
|
|
to standard output.
|
|
|
|
FFmpeg also handles many protocols specified with an URL syntax.
|
|
|
|
Use 'ffmpeg -formats' to see a list of the supported protocols.
|
|
|
|
The protocol @code{http:} is currently used only to communicate with
|
|
FFserver (see the FFserver documentation). When FFmpeg will be a
|
|
video player it will also be used for streaming :-)
|
|
|
|
@chapter Tips
|
|
|
|
@itemize
|
|
@item For streaming at very low bitrate application, use a low frame rate
|
|
and a small GOP size. This is especially true for RealVideo where
|
|
the Linux player does not seem to be very fast, so it can miss
|
|
frames. An example is:
|
|
|
|
@example
|
|
ffmpeg -g 3 -r 3 -t 10 -b 50k -s qcif -f rv10 /tmp/b.rm
|
|
@end example
|
|
|
|
@item The parameter 'q' which is displayed while encoding is the current
|
|
quantizer. The value 1 indicates that a very good quality could
|
|
be achieved. The value 31 indicates the worst quality. If q=31 appears
|
|
too often, it means that the encoder cannot compress enough to meet
|
|
your bitrate. You must either increase the bitrate, decrease the
|
|
frame rate or decrease the frame size.
|
|
|
|
@item If your computer is not fast enough, you can speed up the
|
|
compression at the expense of the compression ratio. You can use
|
|
'-me zero' to speed up motion estimation, and '-intra' to disable
|
|
motion estimation completely (you have only I-frames, which means it
|
|
is about as good as JPEG compression).
|
|
|
|
@item To have very low audio bitrates, reduce the sampling frequency
|
|
(down to 22050 kHz for MPEG audio, 22050 or 11025 for AC3).
|
|
|
|
@item To have a constant quality (but a variable bitrate), use the option
|
|
'-qscale n' when 'n' is between 1 (excellent quality) and 31 (worst
|
|
quality).
|
|
|
|
@item When converting video files, you can use the '-sameq' option which
|
|
uses the same quality factor in the encoder as in the decoder.
|
|
It allows almost lossless encoding.
|
|
|
|
@end itemize
|
|
|
|
|
|
@chapter external libraries
|
|
|
|
FFmpeg can be hooked up with a number of external libraries to add support
|
|
for more formats. None of them are used by default, their use has to be
|
|
explicitly requested by passing the appropriate flags to @file{./configure}.
|
|
|
|
@section AMR
|
|
|
|
AMR comes in two different flavors, WB and NB. FFmpeg can make use of the
|
|
AMR WB (floating-point mode) and the AMR NB (floating-point mode) reference
|
|
decoders and encoders.
|
|
|
|
Go to @url{http://www.penguin.cz/~utx/amr} and follow the instructions for
|
|
installing the libraries. Then pass @code{--enable-libamr-nb} and/or
|
|
@code{--enable-libamr-wb} to configure to enable the libraries.
|
|
|
|
|
|
@chapter Supported File Formats and Codecs
|
|
|
|
You can use the @code{-formats} option to have an exhaustive list.
|
|
|
|
@section File Formats
|
|
|
|
FFmpeg supports the following file formats through the @code{libavformat}
|
|
library:
|
|
|
|
@multitable @columnfractions .4 .1 .1 .4
|
|
@item Supported File Format @tab Encoding @tab Decoding @tab Comments
|
|
@item MPEG audio @tab X @tab X
|
|
@item MPEG-1 systems @tab X @tab X
|
|
@tab muxed audio and video
|
|
@item MPEG-2 PS @tab X @tab X
|
|
@tab also known as @code{VOB} file
|
|
@item MPEG-2 TS @tab @tab X
|
|
@tab also known as DVB Transport Stream
|
|
@item ASF@tab X @tab X
|
|
@item AVI@tab X @tab X
|
|
@item WAV@tab X @tab X
|
|
@item Macromedia Flash@tab X @tab X
|
|
@tab Only embedded audio is decoded.
|
|
@item FLV @tab X @tab X
|
|
@tab Macromedia Flash video files
|
|
@item Real Audio and Video @tab X @tab X
|
|
@item Raw AC3 @tab X @tab X
|
|
@item Raw MJPEG @tab X @tab X
|
|
@item Raw MPEG video @tab X @tab X
|
|
@item Raw PCM8/16 bits, mulaw/Alaw@tab X @tab X
|
|
@item Raw CRI ADX audio @tab X @tab X
|
|
@item Raw Shorten audio @tab @tab X
|
|
@item SUN AU format @tab X @tab X
|
|
@item NUT @tab X @tab X @tab NUT Open Container Format
|
|
@item QuickTime @tab X @tab X
|
|
@item MPEG-4 @tab X @tab X
|
|
@tab MPEG-4 is a variant of QuickTime.
|
|
@item Raw MPEG4 video @tab X @tab X
|
|
@item DV @tab X @tab X
|
|
@item 4xm @tab @tab X
|
|
@tab 4X Technologies format, used in some games.
|
|
@item Playstation STR @tab @tab X
|
|
@item Id RoQ @tab X @tab X
|
|
@tab Used in Quake III, Jedi Knight 2, other computer games.
|
|
@item Interplay MVE @tab @tab X
|
|
@tab Format used in various Interplay computer games.
|
|
@item WC3 Movie @tab @tab X
|
|
@tab Multimedia format used in Origin's Wing Commander III computer game.
|
|
@item Sega FILM/CPK @tab @tab X
|
|
@tab Used in many Sega Saturn console games.
|
|
@item Westwood Studios VQA/AUD @tab @tab X
|
|
@tab Multimedia formats used in Westwood Studios games.
|
|
@item Id Cinematic (.cin) @tab @tab X
|
|
@tab Used in Quake II.
|
|
@item FLIC format @tab @tab X
|
|
@tab .fli/.flc files
|
|
@item Sierra VMD @tab @tab X
|
|
@tab Used in Sierra CD-ROM games.
|
|
@item Sierra Online @tab @tab X
|
|
@tab .sol files used in Sierra Online games.
|
|
@item Matroska @tab @tab X
|
|
@item Electronic Arts Multimedia @tab @tab X
|
|
@tab Used in various EA games; files have extensions like WVE and UV2.
|
|
@item Nullsoft Video (NSV) format @tab @tab X
|
|
@item ADTS AAC audio @tab X @tab X
|
|
@item Creative VOC @tab X @tab X @tab Created for the Sound Blaster Pro.
|
|
@item American Laser Games MM @tab @tab X
|
|
@tab Multimedia format used in games like Mad Dog McCree
|
|
@item AVS @tab @tab X
|
|
@tab Multimedia format used by the Creature Shock game.
|
|
@item Smacker @tab @tab X
|
|
@tab Multimedia format used by many games.
|
|
@item GXF @tab X @tab X
|
|
@tab General eXchange Format SMPTE 360M, used by Thomson Grass Valley playout servers.
|
|
@item CIN @tab @tab X
|
|
@tab Multimedia format used by Delphine Software games.
|
|
@item MXF @tab @tab X
|
|
@tab Material eXchange Format SMPTE 377M, used by D-Cinema, broadcast industry.
|
|
@item SEQ @tab @tab X
|
|
@tab Tiertex .seq files used in the DOS CDROM version of the game Flashback.
|
|
@item DXA @tab @tab X
|
|
@tab This format is used in non-Windows version of Feeble Files game and
|
|
different game cutscenes repacked for use with ScummVM.
|
|
@item THP @tab @tab X
|
|
@tab Used on the Nintendo GameCube.
|
|
@item C93 @tab @tab X
|
|
@tab Used in the game Cyberia from Interplay.
|
|
@item Bethsoft VID @tab @tab X
|
|
@tab Used in some games from Bethesda Softworks.
|
|
@item CRYO APC @tab @tab X
|
|
@tab Audio format used in some games by CRYO Interactive Entertainment.
|
|
@end multitable
|
|
|
|
@code{X} means that encoding (resp. decoding) is supported.
|
|
|
|
@section Image Formats
|
|
|
|
FFmpeg can read and write images for each frame of a video sequence. The
|
|
following image formats are supported:
|
|
|
|
@multitable @columnfractions .4 .1 .1 .4
|
|
@item Supported Image Format @tab Encoding @tab Decoding @tab Comments
|
|
@item PGM, PPM @tab X @tab X
|
|
@item PAM @tab X @tab X @tab PAM is a PNM extension with alpha support.
|
|
@item PGMYUV @tab X @tab X @tab PGM with U and V components in YUV 4:2:0
|
|
@item JPEG @tab X @tab X @tab Progressive JPEG is not supported.
|
|
@item .Y.U.V @tab X @tab X @tab one raw file per component
|
|
@item animated GIF @tab X @tab X @tab Only uncompressed GIFs are generated.
|
|
@item PNG @tab X @tab X @tab 2 bit and 4 bit/pixel not supported yet.
|
|
@item Targa @tab @tab X @tab Targa (.TGA) image format.
|
|
@item TIFF @tab X @tab X @tab YUV, JPEG and some extension is not supported yet.
|
|
@item SGI @tab X @tab X @tab SGI RGB image format
|
|
@item PTX @tab @tab X @tab V.Flash PTX format
|
|
@end multitable
|
|
|
|
@code{X} means that encoding (resp. decoding) is supported.
|
|
|
|
@section Video Codecs
|
|
|
|
@multitable @columnfractions .4 .1 .1 .4
|
|
@item Supported Codec @tab Encoding @tab Decoding @tab Comments
|
|
@item MPEG-1 video @tab X @tab X
|
|
@item MPEG-2 video @tab X @tab X
|
|
@item MPEG-4 @tab X @tab X
|
|
@item MSMPEG4 V1 @tab X @tab X
|
|
@item MSMPEG4 V2 @tab X @tab X
|
|
@item MSMPEG4 V3 @tab X @tab X
|
|
@item WMV7 @tab X @tab X
|
|
@item WMV8 @tab X @tab X @tab not completely working
|
|
@item WMV9 @tab @tab X @tab not completely working
|
|
@item VC1 @tab @tab X
|
|
@item H.261 @tab X @tab X
|
|
@item H.263(+) @tab X @tab X @tab also known as RealVideo 1.0
|
|
@item H.264 @tab @tab X
|
|
@item RealVideo 1.0 @tab X @tab X
|
|
@item RealVideo 2.0 @tab X @tab X
|
|
@item MJPEG @tab X @tab X
|
|
@item lossless MJPEG @tab X @tab X
|
|
@item JPEG-LS @tab X @tab X @tab fourcc: MJLS, lossless and near-lossless is supported
|
|
@item Apple MJPEG-B @tab @tab X
|
|
@item Sunplus MJPEG @tab @tab X @tab fourcc: SP5X
|
|
@item DV @tab X @tab X
|
|
@item HuffYUV @tab X @tab X
|
|
@item FFmpeg Video 1 @tab X @tab X @tab experimental lossless codec (fourcc: FFV1)
|
|
@item FFmpeg Snow @tab X @tab X @tab experimental wavelet codec (fourcc: SNOW)
|
|
@item Asus v1 @tab X @tab X @tab fourcc: ASV1
|
|
@item Asus v2 @tab X @tab X @tab fourcc: ASV2
|
|
@item Creative YUV @tab @tab X @tab fourcc: CYUV
|
|
@item Sorenson Video 1 @tab X @tab X @tab fourcc: SVQ1
|
|
@item Sorenson Video 3 @tab @tab X @tab fourcc: SVQ3
|
|
@item On2 VP3 @tab @tab X @tab still experimental
|
|
@item On2 VP5 @tab @tab X @tab fourcc: VP50
|
|
@item On2 VP6 @tab @tab X @tab fourcc: VP60,VP61,VP62
|
|
@item Theora @tab X @tab X @tab still experimental
|
|
@item Intel Indeo 3 @tab @tab X
|
|
@item FLV @tab X @tab X @tab Sorenson H.263 used in Flash
|
|
@item Flash Screen Video @tab X @tab X @tab fourcc: FSV1
|
|
@item ATI VCR1 @tab @tab X @tab fourcc: VCR1
|
|
@item ATI VCR2 @tab @tab X @tab fourcc: VCR2
|
|
@item Cirrus Logic AccuPak @tab @tab X @tab fourcc: CLJR
|
|
@item 4X Video @tab @tab X @tab Used in certain computer games.
|
|
@item Sony Playstation MDEC @tab @tab X
|
|
@item Id RoQ @tab X @tab X @tab Used in Quake III, Jedi Knight 2, other computer games.
|
|
@item Xan/WC3 @tab @tab X @tab Used in Wing Commander III .MVE files.
|
|
@item Interplay Video @tab @tab X @tab Used in Interplay .MVE files.
|
|
@item Apple Animation @tab X @tab X @tab fourcc: 'rle '
|
|
@item Apple Graphics @tab @tab X @tab fourcc: 'smc '
|
|
@item Apple Video @tab @tab X @tab fourcc: rpza
|
|
@item Apple QuickDraw @tab @tab X @tab fourcc: qdrw
|
|
@item Cinepak @tab @tab X
|
|
@item Microsoft RLE @tab @tab X
|
|
@item Microsoft Video-1 @tab @tab X
|
|
@item Westwood VQA @tab @tab X
|
|
@item Id Cinematic Video @tab @tab X @tab Used in Quake II.
|
|
@item Planar RGB @tab @tab X @tab fourcc: 8BPS
|
|
@item FLIC video @tab @tab X
|
|
@item Duck TrueMotion v1 @tab @tab X @tab fourcc: DUCK
|
|
@item Duck TrueMotion v2 @tab @tab X @tab fourcc: TM20
|
|
@item VMD Video @tab @tab X @tab Used in Sierra VMD files.
|
|
@item MSZH @tab @tab X @tab Part of LCL
|
|
@item ZLIB @tab X @tab X @tab Part of LCL, encoder experimental
|
|
@item TechSmith Camtasia @tab @tab X @tab fourcc: TSCC
|
|
@item IBM Ultimotion @tab @tab X @tab fourcc: ULTI
|
|
@item Miro VideoXL @tab @tab X @tab fourcc: VIXL
|
|
@item QPEG @tab @tab X @tab fourccs: QPEG, Q1.0, Q1.1
|
|
@item LOCO @tab @tab X @tab
|
|
@item Winnov WNV1 @tab @tab X @tab
|
|
@item Autodesk Animator Studio Codec @tab @tab X @tab fourcc: AASC
|
|
@item Fraps FPS1 @tab @tab X @tab
|
|
@item CamStudio @tab @tab X @tab fourcc: CSCD
|
|
@item American Laser Games Video @tab @tab X @tab Used in games like Mad Dog McCree
|
|
@item ZMBV @tab X @tab X @tab Encoder works only on PAL8
|
|
@item AVS Video @tab @tab X @tab Video encoding used by the Creature Shock game.
|
|
@item Smacker Video @tab @tab X @tab Video encoding used in Smacker.
|
|
@item RTjpeg @tab @tab X @tab Video encoding used in NuppelVideo files.
|
|
@item KMVC @tab @tab X @tab Codec used in Worms games.
|
|
@item VMware Video @tab @tab X @tab Codec used in videos captured by VMware.
|
|
@item Cin Video @tab @tab X @tab Codec used in Delphine Software games.
|
|
@item Tiertex Seq Video @tab @tab X @tab Codec used in DOS CDROM FlashBack game.
|
|
@item DXA Video @tab @tab X @tab Codec originally used in Feeble Files game.
|
|
@item AVID DNxHD @tab @tab X @tab aka SMPTE VC3
|
|
@item C93 Video @tab @tab X @tab Codec used in Cyberia game.
|
|
@item THP @tab @tab X @tab Used on the Nintendo GameCube.
|
|
@item Bethsoft VID @tab @tab X @tab Used in some games from Bethesda Softworks.
|
|
@item Renderware TXD @tab @tab X @tab Texture dictionaries used by the Renderware Engine.
|
|
@end multitable
|
|
|
|
@code{X} means that encoding (resp. decoding) is supported.
|
|
|
|
@section Audio Codecs
|
|
|
|
@multitable @columnfractions .4 .1 .1 .1 .7
|
|
@item Supported Codec @tab Encoding @tab Decoding @tab Comments
|
|
@item MPEG audio layer 2 @tab IX @tab IX
|
|
@item MPEG audio layer 1/3 @tab IX @tab IX
|
|
@tab MP3 encoding is supported through the external library LAME.
|
|
@item AC3 @tab IX @tab IX
|
|
@tab liba52 is used internally for decoding.
|
|
@item Vorbis @tab X @tab X
|
|
@item WMA V1/V2 @tab X @tab X
|
|
@item AAC @tab X @tab X
|
|
@tab Supported through the external library libfaac/libfaad.
|
|
@item Microsoft ADPCM @tab X @tab X
|
|
@item MS IMA ADPCM @tab X @tab X
|
|
@item QT IMA ADPCM @tab @tab X
|
|
@item 4X IMA ADPCM @tab @tab X
|
|
@item G.726 ADPCM @tab X @tab X
|
|
@item Duck DK3 IMA ADPCM @tab @tab X
|
|
@tab Used in some Sega Saturn console games.
|
|
@item Duck DK4 IMA ADPCM @tab @tab X
|
|
@tab Used in some Sega Saturn console games.
|
|
@item Westwood Studios IMA ADPCM @tab @tab X
|
|
@tab Used in Westwood Studios games like Command and Conquer.
|
|
@item SMJPEG IMA ADPCM @tab @tab X
|
|
@tab Used in certain Loki game ports.
|
|
@item CD-ROM XA ADPCM @tab @tab X
|
|
@item CRI ADX ADPCM @tab X @tab X
|
|
@tab Used in Sega Dreamcast games.
|
|
@item Electronic Arts ADPCM @tab @tab X
|
|
@tab Used in various EA titles.
|
|
@item Creative ADPCM @tab @tab X
|
|
@tab 16 -> 4, 8 -> 4, 8 -> 3, 8 -> 2
|
|
@item THP ADPCM @tab @tab X
|
|
@tab Used on the Nintendo GameCube.
|
|
@item RA144 @tab @tab X
|
|
@tab Real 14400 bit/s codec
|
|
@item RA288 @tab @tab X
|
|
@tab Real 28800 bit/s codec
|
|
@item RADnet @tab X @tab IX
|
|
@tab Real low bitrate AC3 codec, liba52 is used for decoding.
|
|
@item AMR-NB @tab X @tab X
|
|
@tab Supported through an external library.
|
|
@item AMR-WB @tab X @tab X
|
|
@tab Supported through an external library.
|
|
@item DV audio @tab @tab X
|
|
@item Id RoQ DPCM @tab X @tab X
|
|
@tab Used in Quake III, Jedi Knight 2, other computer games.
|
|
@item Interplay MVE DPCM @tab @tab X
|
|
@tab Used in various Interplay computer games.
|
|
@item Xan DPCM @tab @tab X
|
|
@tab Used in Origin's Wing Commander IV AVI files.
|
|
@item Sierra Online DPCM @tab @tab X
|
|
@tab Used in Sierra Online game audio files.
|
|
@item Apple MACE 3 @tab @tab X
|
|
@item Apple MACE 6 @tab @tab X
|
|
@item FLAC lossless audio @tab X @tab X
|
|
@item Shorten lossless audio @tab @tab X
|
|
@item Apple lossless audio @tab @tab X
|
|
@tab QuickTime fourcc 'alac'
|
|
@item FFmpeg Sonic @tab X @tab X
|
|
@tab experimental lossy/lossless codec
|
|
@item Qdesign QDM2 @tab @tab X
|
|
@tab there are still some distortions
|
|
@item Real COOK @tab @tab X
|
|
@tab All versions except 5.1 are supported
|
|
@item DSP Group TrueSpeech @tab @tab X
|
|
@item True Audio (TTA) @tab @tab X
|
|
@item Smacker Audio @tab @tab X
|
|
@item WavPack Audio @tab @tab X
|
|
@item Cin Audio @tab @tab X
|
|
@tab Codec used in Delphine Software games.
|
|
@item Intel Music Coder @tab @tab X
|
|
@item Musepack @tab @tab X
|
|
@tab Only SV7 is supported
|
|
@item DT$ Coherent Audio @tab @tab X
|
|
@item ATRAC 3 @tab @tab X
|
|
@end multitable
|
|
|
|
@code{X} means that encoding (resp. decoding) is supported.
|
|
|
|
@code{I} means that an integer-only version is available, too (ensures high
|
|
performance on systems without hardware floating point support).
|
|
|
|
@chapter Platform Specific information
|
|
|
|
@section BSD
|
|
|
|
BSD make will not build FFmpeg, you need to install and use GNU Make
|
|
(@file{gmake}).
|
|
|
|
@section Windows
|
|
|
|
To get help and instructions for using FFmpeg under Windows, check out
|
|
the FFmpeg Windows Help Forum at
|
|
@url{http://arrozcru.no-ip.org/ffmpeg/}.
|
|
|
|
@subsection Native Windows compilation
|
|
|
|
@itemize
|
|
@item Install the current versions of MSYS and MinGW from
|
|
@url{http://www.mingw.org/}. You can find detailed installation
|
|
instructions in the download section and the FAQ.
|
|
|
|
NOTE: Use at least bash 3.1. Older versions are known to be failing on the
|
|
configure script.
|
|
|
|
@item If you want to test the FFplay, also download
|
|
the MinGW development library of SDL 1.2.x
|
|
(@file{SDL-devel-1.2.x-mingw32.tar.gz}) from
|
|
@url{http://www.libsdl.org}. Unpack it in a temporary directory, and
|
|
unpack the archive @file{i386-mingw32msvc.tar.gz} in the MinGW tool
|
|
directory. Edit the @file{sdl-config} script so that it gives the
|
|
correct SDL directory when invoked.
|
|
|
|
@item Extract the current version of FFmpeg.
|
|
|
|
@item Start the MSYS shell (file @file{msys.bat}).
|
|
|
|
@item Change to the FFmpeg directory and follow
|
|
the instructions of how to compile FFmpeg (file
|
|
@file{INSTALL}). Usually, launching @file{./configure} and @file{make}
|
|
suffices. If you have problems using SDL, verify that
|
|
@file{sdl-config} can be launched from the MSYS command line.
|
|
|
|
@item You can install FFmpeg in @file{Program Files/FFmpeg} by typing
|
|
@file{make install}. Do not forget to copy @file{SDL.dll} to the place
|
|
you launch @file{ffplay} from.
|
|
|
|
@end itemize
|
|
|
|
Notes:
|
|
@itemize
|
|
|
|
@item The target @file{make wininstaller} can be used to create a
|
|
Nullsoft based Windows installer for FFmpeg and FFplay. @file{SDL.dll}
|
|
must be copied to the FFmpeg directory in order to build the
|
|
installer.
|
|
|
|
@item By using @code{./configure --enable-shared} when configuring FFmpeg,
|
|
you can build @file{avcodec.dll} and @file{avformat.dll}. With
|
|
@code{make install} you install the FFmpeg DLLs and the associated
|
|
headers in @file{Program Files/FFmpeg}.
|
|
|
|
@item Visual C++ compatibility: If you used @code{./configure --enable-shared}
|
|
when configuring FFmpeg, FFmpeg tries to use the Microsoft Visual
|
|
C++ @code{lib} tool to build @code{avcodec.lib} and
|
|
@code{avformat.lib}. With these libraries you can link your Visual C++
|
|
code directly with the FFmpeg DLLs (see below).
|
|
|
|
@end itemize
|
|
|
|
@subsection Visual C++ compatibility
|
|
|
|
FFmpeg will not compile under Visual C++ -- and it has too many
|
|
dependencies on the GCC compiler to make a port viable. However,
|
|
if you want to use the FFmpeg libraries in your own applications,
|
|
you can still compile those applications using Visual C++. An
|
|
important restriction to this is that you have to use the
|
|
dynamically linked versions of the FFmpeg libraries (i.e. the
|
|
DLLs), and you have to make sure that Visual-C++-compatible
|
|
import libraries are created during the FFmpeg build process.
|
|
|
|
This description of how to use the FFmpeg libraries with Visual C++ is
|
|
based on Visual C++ 2005 Express Edition Beta 2. If you have a different
|
|
version, you might have to modify the procedures slightly.
|
|
|
|
Here are the step-by-step instructions for building the FFmpeg libraries
|
|
so they can be used with Visual C++:
|
|
|
|
@enumerate
|
|
|
|
@item Install Visual C++ (if you have not done so already).
|
|
|
|
@item Install MinGW and MSYS as described above.
|
|
|
|
@item Add a call to @file{vcvars32.bat} (which sets up the environment
|
|
variables for the Visual C++ tools) as the first line of
|
|
@file{msys.bat}. The standard location for @file{vcvars32.bat} is
|
|
@file{C:\Program Files\Microsoft Visual Studio 8\VC\bin\vcvars32.bat},
|
|
and the standard location for @file{msys.bat} is
|
|
@file{C:\msys\1.0\msys.bat}. If this corresponds to your setup, add the
|
|
following line as the first line of @file{msys.bat}:
|
|
|
|
@code{call "C:\Program Files\Microsoft Visual Studio 8\VC\bin\vcvars32.bat"}
|
|
|
|
@item Start the MSYS shell (file @file{msys.bat}) and type @code{link.exe}.
|
|
If you get a help message with the command line options of @code{link.exe},
|
|
this means your environment variables are set up correctly, the
|
|
Microsoft linker is on the path and will be used by FFmpeg to
|
|
create Visual-C++-compatible import libraries.
|
|
|
|
@item Extract the current version of FFmpeg and change to the FFmpeg directory.
|
|
|
|
@item Type the command
|
|
@code{./configure --enable-shared --disable-static --enable-memalign-hack}
|
|
to configure and, if that did not produce any errors,
|
|
type @code{make} to build FFmpeg.
|
|
|
|
@item The subdirectories @file{libavformat}, @file{libavcodec}, and
|
|
@file{libavutil} should now contain the files @file{avformat.dll},
|
|
@file{avformat.lib}, @file{avcodec.dll}, @file{avcodec.lib},
|
|
@file{avutil.dll}, and @file{avutil.lib}, respectively. Copy the three
|
|
DLLs to your System32 directory (typically @file{C:\Windows\System32}).
|
|
|
|
@end enumerate
|
|
|
|
And here is how to use these libraries with Visual C++:
|
|
|
|
@enumerate
|
|
|
|
@item Create a new console application ("File / New / Project") and then
|
|
select "Win32 Console Application". On the appropriate page of the
|
|
Application Wizard, uncheck the "Precompiled headers" option.
|
|
|
|
@item Write the source code for your application, or, for testing, just
|
|
copy the code from an existing sample application into the source file
|
|
that Visual C++ has already created for you. (Note that your source
|
|
filehas to have a @code{.cpp} extension; otherwise, Visual C++ will not
|
|
compile the FFmpeg headers correctly because in C mode, it does not
|
|
recognize the @code{inline} keyword.) For example, you can copy
|
|
@file{output_example.c} from the FFmpeg distribution (but you will
|
|
have to make minor modifications so the code will compile under
|
|
C++, see below).
|
|
|
|
@item Open the "Project / Properties" dialog box. In the "Configuration"
|
|
combo box, select "All Configurations" so that the changes you make will
|
|
affect both debug and release builds. In the tree view on the left hand
|
|
side, select "C/C++ / General", then edit the "Additional Include
|
|
Directories" setting to contain the complete paths to the
|
|
@file{libavformat}, @file{libavcodec}, and @file{libavutil}
|
|
subdirectories of your FFmpeg directory. Note that the directories have
|
|
to be separated using semicolons. Now select "Linker / General" from the
|
|
tree view and edit the "Additional Library Directories" setting to
|
|
contain the same three directories.
|
|
|
|
@item Still in the "Project / Properties" dialog box, select "Linker / Input"
|
|
from the tree view, then add the files @file{avformat.lib},
|
|
@file{avcodec.lib}, and @file{avutil.lib} to the end of the "Additional
|
|
Dependencies". Note that the names of the libraries have to be separated
|
|
using spaces.
|
|
|
|
@item Now, select "C/C++ / Code Generation" from the tree view. Select
|
|
"Debug" in the "Configuration" combo box. Make sure that "Runtime
|
|
Library" is set to "Multi-threaded Debug DLL". Then, select "Release" in
|
|
the "Configuration" combo box and make sure that "Runtime Library" is
|
|
set to "Multi-threaded DLL".
|
|
|
|
@item Click "OK" to close the "Project / Properties" dialog box and build
|
|
the application. Hopefully, it should compile and run cleanly. If you
|
|
used @file{output_example.c} as your sample application, you will get a
|
|
few compiler errors, but they are easy to fix. The first type of error
|
|
occurs because Visual C++ does not allow an @code{int} to be converted to
|
|
an @code{enum} without a cast. To solve the problem, insert the required
|
|
casts (this error occurs once for a @code{CodecID} and once for a
|
|
@code{CodecType}). The second type of error occurs because C++ requires
|
|
the return value of @code{malloc} to be cast to the exact type of the
|
|
pointer it is being assigned to. Visual C++ will complain that, for
|
|
example, @code{(void *)} is being assigned to @code{(uint8_t *)} without
|
|
an explicit cast. So insert an explicit cast in these places to silence
|
|
the compiler. The third type of error occurs because the @code{snprintf}
|
|
library function is called @code{_snprintf} under Visual C++. So just
|
|
add an underscore to fix the problem. With these changes,
|
|
@file{output_example.c} should compile under Visual C++, and the
|
|
resulting executable should produce valid video files.
|
|
|
|
@end enumerate
|
|
|
|
@subsection Cross compilation for Windows with Linux
|
|
|
|
You must use the MinGW cross compilation tools available at
|
|
@url{http://www.mingw.org/}.
|
|
|
|
Then configure FFmpeg with the following options:
|
|
@example
|
|
./configure --target-os=mingw32 --cross-prefix=i386-mingw32msvc-
|
|
@end example
|
|
(you can change the cross-prefix according to the prefix chosen for the
|
|
MinGW tools).
|
|
|
|
Then you can easily test FFmpeg with Wine
|
|
(@url{http://www.winehq.com/}).
|
|
|
|
@subsection Compilation under Cygwin
|
|
|
|
Cygwin works very much like Unix.
|
|
|
|
Just install your Cygwin with all the "Base" packages, plus the
|
|
following "Devel" ones:
|
|
@example
|
|
binutils, gcc-core, make, subversion
|
|
@end example
|
|
|
|
Do not install binutils-20060709-1 (they are buggy on shared builds);
|
|
use binutils-20050610-1 instead.
|
|
|
|
Then run
|
|
|
|
@example
|
|
./configure --enable-static --disable-shared
|
|
@end example
|
|
|
|
to make a static build or
|
|
|
|
@example
|
|
./configure --enable-shared --disable-static
|
|
@end example
|
|
|
|
to build shared libraries.
|
|
|
|
If you want to build FFmpeg with additional libraries, download Cygwin
|
|
"Devel" packages for Ogg and Vorbis from any Cygwin packages repository
|
|
and/or SDL, xvid, faac, faad2 packages from Cygwin Ports,
|
|
(@url{http://cygwinports.dotsrc.org/}).
|
|
|
|
@subsection Crosscompilation for Windows under Cygwin
|
|
|
|
With Cygwin you can create Windows binaries that do not need the cygwin1.dll.
|
|
|
|
Just install your Cygwin as explained before, plus these additional
|
|
"Devel" packages:
|
|
@example
|
|
gcc-mingw-core, mingw-runtime, mingw-zlib
|
|
@end example
|
|
|
|
and add some special flags to your configure invocation.
|
|
|
|
For a static build run
|
|
@example
|
|
./configure --target-os=mingw32 --enable-memalign-hack --enable-static --disable-shared --extra-cflags=-mno-cygwin --extra-libs=-mno-cygwin
|
|
@end example
|
|
|
|
and for a build with shared libraries
|
|
@example
|
|
./configure --target-os=mingw32 --enable-memalign-hack --enable-shared --disable-static --extra-cflags=-mno-cygwin --extra-libs=-mno-cygwin
|
|
@end example
|
|
|
|
@section BeOS
|
|
|
|
The configure script should guess the configuration itself.
|
|
Networking support is currently not finished.
|
|
errno issues fixed by Andrew Bachmann.
|
|
|
|
Old stuff:
|
|
|
|
François Revol - revol at free dot fr - April 2002
|
|
|
|
The configure script should guess the configuration itself,
|
|
however I still did not test building on the net_server version of BeOS.
|
|
|
|
FFserver is broken (needs poll() implementation).
|
|
|
|
There are still issues with errno codes, which are negative in BeOS, and
|
|
that FFmpeg negates when returning. This ends up turning errors into
|
|
valid results, then crashes.
|
|
(To be fixed)
|
|
|
|
@chapter Developers Guide
|
|
|
|
@section API
|
|
@itemize @bullet
|
|
@item libavcodec is the library containing the codecs (both encoding and
|
|
decoding). Look at @file{libavcodec/apiexample.c} to see how to use it.
|
|
|
|
@item libavformat is the library containing the file format handling (mux and
|
|
demux code for several formats). Look at @file{ffplay.c} to use it in a
|
|
player. See @file{output_example.c} to use it to generate audio or video
|
|
streams.
|
|
|
|
@end itemize
|
|
|
|
@section Integrating libavcodec or libavformat in your program
|
|
|
|
You can integrate all the source code of the libraries to link them
|
|
statically to avoid any version problem. All you need is to provide a
|
|
'config.mak' and a 'config.h' in the parent directory. See the defines
|
|
generated by ./configure to understand what is needed.
|
|
|
|
You can use libavcodec or libavformat in your commercial program, but
|
|
@emph{any patch you make must be published}. The best way to proceed is
|
|
to send your patches to the FFmpeg mailing list.
|
|
|
|
@node Coding Rules
|
|
@section Coding Rules
|
|
|
|
FFmpeg is programmed in the ISO C90 language with a few additional
|
|
features from ISO C99, namely:
|
|
@itemize @bullet
|
|
@item
|
|
the @samp{inline} keyword;
|
|
@item
|
|
@samp{//} comments;
|
|
@item
|
|
designated struct initializers (@samp{struct s x = @{ .i = 17 @};})
|
|
@item
|
|
compound literals (@samp{x = (struct s) @{ 17, 23 @};})
|
|
@end itemize
|
|
|
|
These features are supported by all compilers we care about, so we will not
|
|
accept patches to remove their use unless they absolutely do not impair
|
|
clarity and performance.
|
|
|
|
All code must compile with GCC 2.95 and GCC 3.3. Currently, FFmpeg also
|
|
compiles with several other compilers, such as the Compaq ccc compiler
|
|
or Sun Studio 9, and we would like to keep it that way unless it would
|
|
be exceedingly involved. To ensure compatibility, please do not use any
|
|
additional C99 features or GCC extensions. Especially watch out for:
|
|
@itemize @bullet
|
|
@item
|
|
mixing statements and declarations;
|
|
@item
|
|
@samp{long long} (use @samp{int64_t} instead);
|
|
@item
|
|
@samp{__attribute__} not protected by @samp{#ifdef __GNUC__} or similar;
|
|
@item
|
|
GCC statement expressions (@samp{(x = (@{ int y = 4; y; @})}).
|
|
@end itemize
|
|
|
|
Indent size is 4.
|
|
The presentation is the one specified by 'indent -i4 -kr -nut'.
|
|
The TAB character is forbidden outside of Makefiles as is any
|
|
form of trailing whitespace. Commits containing either will be
|
|
rejected by the Subversion repository.
|
|
|
|
Main priority in FFmpeg is simplicity and small code size (=less
|
|
bugs).
|
|
|
|
Comments: Use the JavaDoc/Doxygen
|
|
format (see examples below) so that code documentation
|
|
can be generated automatically. All nontrivial functions should have a comment
|
|
above them explaining what the function does, even if it is just one sentence.
|
|
All structures and their member variables should be documented, too.
|
|
@example
|
|
/**
|
|
* @@file mpeg.c
|
|
* MPEG codec.
|
|
* @@author ...
|
|
*/
|
|
|
|
/**
|
|
* Summary sentence.
|
|
* more text ...
|
|
* ...
|
|
*/
|
|
typedef struct Foobar@{
|
|
int var1; /**< var1 description */
|
|
int var2; ///< var2 description
|
|
/** var3 description */
|
|
int var3;
|
|
@} Foobar;
|
|
|
|
/**
|
|
* Summary sentence.
|
|
* more text ...
|
|
* ...
|
|
* @@param my_parameter description of my_parameter
|
|
* @@return return value description
|
|
*/
|
|
int myfunc(int my_parameter)
|
|
...
|
|
@end example
|
|
|
|
fprintf and printf are forbidden in libavformat and libavcodec,
|
|
please use av_log() instead.
|
|
|
|
Casts should be used only when necessary. Unneeded parentheses
|
|
should also be avoided if they don't make the code easier to understand.
|
|
|
|
@section Development Policy
|
|
|
|
@enumerate
|
|
@item
|
|
You must not commit code which breaks FFmpeg! (Meaning unfinished but
|
|
enabled code which breaks compilation or compiles but does not work or
|
|
breaks the regression tests)
|
|
You can commit unfinished stuff (for testing etc), but it must be disabled
|
|
(#ifdef etc) by default so it does not interfere with other developers'
|
|
work.
|
|
@item
|
|
You do not have to over-test things. If it works for you, and you think it
|
|
should work for others, then commit. If your code has problems
|
|
(portability, triggers compiler bugs, unusual environment etc) they will be
|
|
reported and eventually fixed.
|
|
@item
|
|
Do not commit unrelated changes together, split them into self-contained
|
|
pieces. Also do not forget that if part B depends on part A, but A does not
|
|
depend on B, then A can and should be committed first and separate from B.
|
|
Keeping changes well split into self-contained parts makes reviewing and
|
|
understanding them on the commit log mailing list easier. This also helps
|
|
in case of debugging later on.
|
|
Also if you have doubts about splitting or not splitting, do not hesitate to
|
|
ask/discuss it on the developer mailing list.
|
|
@item
|
|
Do not change behavior of the program (renaming options etc) without
|
|
first discussing it on the ffmpeg-devel mailing list. Do not remove
|
|
functionality from the code. Just improve!
|
|
|
|
Note: Redundant code can be removed.
|
|
@item
|
|
Do not commit changes to the build system (Makefiles, configure script)
|
|
which change behavior, defaults etc, without asking first. The same
|
|
applies to compiler warning fixes, trivial looking fixes and to code
|
|
maintained by other developers. We usually have a reason for doing things
|
|
the way we do. Send your changes as patches to the ffmpeg-devel mailing
|
|
list, and if the code maintainers say OK, you may commit. This does not
|
|
apply to files you wrote and/or maintain.
|
|
@item
|
|
We refuse source indentation and other cosmetic changes if they are mixed
|
|
with functional changes, such commits will be rejected and removed. Every
|
|
developer has his own indentation style, you should not change it. Of course
|
|
if you (re)write something, you can use your own style, even though we would
|
|
prefer if the indentation throughout FFmpeg was consistent (Many projects
|
|
force a given indentation style - we do not.). If you really need to make
|
|
indentation changes (try to avoid this), separate them strictly from real
|
|
changes.
|
|
|
|
NOTE: If you had to put if()@{ .. @} over a large (> 5 lines) chunk of code,
|
|
then either do NOT change the indentation of the inner part within (do not
|
|
move it to the right)! or do so in a separate commit
|
|
@item
|
|
Always fill out the commit log message. Describe in a few lines what you
|
|
changed and why. You can refer to mailing list postings if you fix a
|
|
particular bug. Comments such as "fixed!" or "Changed it." are unacceptable.
|
|
@item
|
|
If you apply a patch by someone else, include the name and email address in
|
|
the log message. Since the ffmpeg-cvslog mailing list is publicly
|
|
archived you should add some SPAM protection to the email address. Send an
|
|
answer to ffmpeg-devel (or wherever you got the patch from) saying that
|
|
you applied the patch.
|
|
@item
|
|
When applying patches that have been discussed (at length) on the mailing
|
|
list, reference the thread in the log message.
|
|
@item
|
|
Do NOT commit to code actively maintained by others without permission.
|
|
Send a patch to ffmpeg-devel instead. If no one answers within a reasonable
|
|
timeframe (12h for build failures and security fixes, 3 days small changes,
|
|
1 week for big patches) then commit your patch if you think it is OK.
|
|
Also note, the maintainer can simply ask for more time to review!
|
|
@item
|
|
Subscribe to the ffmpeg-cvslog mailing list. The diffs of all commits
|
|
are sent there and reviewed by all the other developers. Bugs and possible
|
|
improvements or general questions regarding commits are discussed there. We
|
|
expect you to react if problems with your code are uncovered.
|
|
@item
|
|
Update the documentation if you change behavior or add features. If you are
|
|
unsure how best to do this, send a patch to ffmpeg-devel, the documentation
|
|
maintainer(s) will review and commit your stuff.
|
|
@item
|
|
Try to keep important discussions and requests (also) on the public
|
|
developer mailing list, so that all developers can benefit from them.
|
|
@item
|
|
Never write to unallocated memory, never write over the end of arrays,
|
|
always check values read from some untrusted source before using them
|
|
as array index or other risky things.
|
|
@item
|
|
Remember to check if you need to bump versions for the specific libav
|
|
parts (libavutil, libavcodec, libavformat) you are changing. You need
|
|
to change the version integer and the version string.
|
|
Incrementing the first component means no backward compatibility to
|
|
previous versions (e.g. removal of a function from the public API).
|
|
Incrementing the second component means backward compatible change
|
|
(e.g. addition of a function to the public API).
|
|
Incrementing the third component means a noteworthy binary compatible
|
|
change (e.g. encoder bug fix that matters for the decoder).
|
|
@item
|
|
If you add a new codec, remember to update the changelog, add it to
|
|
the supported codecs table in the documentation and bump the second
|
|
component of the @file{libavcodec} version number appropriately. If
|
|
it has a fourcc, add it to @file{libavformat/avienc.c}, even if it
|
|
is only a decoder.
|
|
@item
|
|
Do not change code to hide warnings without ensuring that the underlying
|
|
logic is correct and thus the warning was inappropriate.
|
|
@item
|
|
If you add a new file, give it a proper license header. Do not copy and
|
|
paste it from a random place, use an existing file as template.
|
|
@end enumerate
|
|
|
|
We think our rules are not too hard. If you have comments, contact us.
|
|
|
|
Note, these rules are mostly borrowed from the MPlayer project.
|
|
|
|
@section Submitting patches
|
|
|
|
First, (@pxref{Coding Rules}) above if you did not yet.
|
|
|
|
When you submit your patch, try to send a unified diff (diff '-up'
|
|
option). I cannot read other diffs :-)
|
|
|
|
Also please do not submit patches which contain several unrelated changes.
|
|
Split them into individual self-contained patches; this makes reviewing
|
|
them much easier.
|
|
|
|
Run the regression tests before submitting a patch so that you can
|
|
verify that there are no big problems.
|
|
|
|
Patches should be posted as base64 encoded attachments (or any other
|
|
encoding which ensures that the patch will not be trashed during
|
|
transmission) to the ffmpeg-devel mailing list, see
|
|
@url{http://lists.mplayerhq.hu/mailman/listinfo/ffmpeg-devel}
|
|
|
|
It also helps quite a bit if you tell us what the patch does (for example
|
|
'replaces lrint by lrintf'), and why (for example '*BSD isn't C99 compliant
|
|
and has no lrint()')
|
|
|
|
Also please if you send several patches, send each patch as separate mail,
|
|
do not attach several unrelated patches to the same mail.
|
|
|
|
@section patch submission checklist
|
|
|
|
@enumerate
|
|
@item
|
|
Do the regression tests pass with the patch applied?
|
|
@item
|
|
Is the patch a unified diff?
|
|
@item
|
|
Is the patch against latest FFmpeg SVN?
|
|
@item
|
|
Are you subscribed to ffmpeg-dev?
|
|
(the list is subscribers only due to spam)
|
|
@item
|
|
Have you checked that the changes are minimal, so that the same cannot be
|
|
achieved with a smaller patch and/or simpler final code?
|
|
@item
|
|
If the change is to speed critical code, did you benchmark it?
|
|
@item
|
|
If you did any benchmarks, did you provide them in the mail?
|
|
@item
|
|
Have you checked that the patch does not introduce buffer overflows or
|
|
other security issues?
|
|
@item
|
|
Is the patch created from the root of the source tree, so it can be
|
|
applied with @code{patch -p0}?
|
|
@item
|
|
Does the patch not mix functional and cosmetic changes?
|
|
@item
|
|
Did you add tabs or trailing whitespace to the code? Both are forbidden.
|
|
@item
|
|
Is the patch attached to the email you send?
|
|
@item
|
|
Is the mime type of the patch correct? It should be text/x-diff or
|
|
text/x-patch or at least text/plain and not application/octet-stream.
|
|
@item
|
|
If the patch fixes a bug, did you provide a verbose analysis of the bug?
|
|
@item
|
|
If the patch fixes a bug, did you provide enough information, including
|
|
a sample, so the bug can be reproduced and the fix can be verified?
|
|
Note please do not attach samples >100k to mails but rather provide a
|
|
URL, you can upload to ftp://upload.mplayerhq.hu
|
|
@item
|
|
Did you provide a verbose summary about what the patch does change?
|
|
@item
|
|
Did you provide a verbose explanation why it changes things like it does?
|
|
@item
|
|
Did you provide a verbose summary of the user visible advantages and
|
|
disadvantages if the patch is applied?
|
|
@item
|
|
Did you provide an example so we can verify the new feature added by the
|
|
patch easily?
|
|
@item
|
|
If you added a new file, did you insert a license header? It should be
|
|
taken from FFmpeg, not randomly copied and pasted from somewhere else.
|
|
@item
|
|
You should maintain alphabetical order in alphabetically ordered lists as
|
|
long as doing so does not break API/ABI compatibility.
|
|
@item
|
|
Did you provide a suggestion for a clear commit log message?
|
|
@end enumerate
|
|
|
|
@section Patch review process
|
|
|
|
All patches posted to ffmpeg-devel will be reviewed, unless they contain a
|
|
clear note that the patch is not for SVN.
|
|
Reviews and comments will be posted as replies to the patch on the
|
|
mailing list. The patch submitter then has to take care of every comment,
|
|
that can be by resubmitting a changed patch or by discussion. Resubmitted
|
|
patches will themselves be reviewed like any other patch. If at some point
|
|
a patch passes review with no comments then it is approved, that can for
|
|
simple and small patches happen immediately while large patches will generally
|
|
have to be changed and reviewed many times before they are approved.
|
|
After a patch is approved it will be committed to the repository.
|
|
|
|
We will review all submitted patches, but sometimes we are quite busy so
|
|
especially for large patches this can take several weeks.
|
|
|
|
When resubmitting patches, please do not make any significant changes
|
|
not related to the comments received during review. Such patches will
|
|
be rejected. Instead, submit significant changes or new features as
|
|
separate patches.
|
|
|
|
@section Regression tests
|
|
|
|
Before submitting a patch (or committing to the repository), you should at least
|
|
test that you did not break anything.
|
|
|
|
The regression tests build a synthetic video stream and a synthetic
|
|
audio stream. These are then encoded and decoded with all codecs or
|
|
formats. The CRC (or MD5) of each generated file is recorded in a
|
|
result file. A 'diff' is launched to compare the reference results and
|
|
the result file.
|
|
|
|
The regression tests then go on to test the FFserver code with a
|
|
limited set of streams. It is important that this step runs correctly
|
|
as well.
|
|
|
|
Run 'make test' to test all the codecs and formats.
|
|
|
|
Run 'make fulltest' to test all the codecs, formats and FFserver.
|
|
|
|
[Of course, some patches may change the results of the regression tests. In
|
|
this case, the reference results of the regression tests shall be modified
|
|
accordingly].
|
|
|
|
@bye
|