patch by Anssi Hannula, anssi.hannula gmail com Originally committed as revision 8656 to svn://svn.ffmpeg.org/ffmpeg/trunk
		
			
				
	
	
		
			1668 lines
		
	
	
		
			57 KiB
		
	
	
	
		
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			1668 lines
		
	
	
		
			57 KiB
		
	
	
	
		
			Plaintext
		
	
	
	
	
	
| \input texinfo @c -*- texinfo -*-
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| 
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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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| 
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| 
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| @chapter Introduction
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| 
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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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| 
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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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| 
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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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| 
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| @chapter Quick Start
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| 
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| @c man begin EXAMPLES
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| @section Video and Audio grabbing
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| 
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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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| 
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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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| 
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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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| 
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| @section X11 grabbing
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| 
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| FFmpeg can grab the X11 display.
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| 
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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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| 
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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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| 
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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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| 
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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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| 
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| @section Video and Audio file format conversion
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| 
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| * FFmpeg can use any supported file format and protocol as input:
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| 
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| Examples:
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| 
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| * You can use YUV files as input:
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| 
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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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| 
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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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| 
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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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| 
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| * You can input from a raw YUV420P file:
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| 
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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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| 
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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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| 
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| * You can output to a raw YUV420P file:
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| 
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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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| 
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| * You can set several input files and output files:
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| 
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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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| 
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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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| 
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| * You can also do audio and video conversions at the same time:
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| 
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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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| 
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| Converts a.wav to MPEG audio at 22050Hz sample rate.
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| 
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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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| 
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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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| 
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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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| 
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| * You can transcode decrypted VOBs
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| 
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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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| 
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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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| 
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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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| 
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| @chapter Invocation
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| 
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| @section Syntax
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| 
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| The generic syntax is:
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| 
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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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| 
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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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| 
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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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| 
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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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| 
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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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| 
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| The format option may be needed for raw input files.
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| 
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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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| 
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| @c man begin OPTIONS
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| @section Main options
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| 
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| @table @option
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| @item -L
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| Show license.
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| 
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| @item -h
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| Show help.
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| 
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| @item -version
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| Show version.
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| 
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| @item -formats
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| Show available formats, codecs, protocols, ...
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| 
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| @item -f fmt
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| Force format.
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| 
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| @item -i filename
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| input filename
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| 
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| @item -y
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| Overwrite output files.
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| 
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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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| 
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| @item -fs limit_size
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| Set the file size limit.
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| 
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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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| 
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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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| 
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| @item -title string
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| Set the title.
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| 
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| @item -timestamp time
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| Set the timestamp.
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| 
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| @item -author string
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| Set the author.
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| 
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| @item -copyright string
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| Set the copyright.
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| 
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| @item -comment string
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| Set the comment.
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| 
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| @item -album string
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| Set the album.
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| 
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| @item -track number
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| Set the track.
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| 
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| @item -year number
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| Set the year.
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| 
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| @item -v verbose
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| Control amount of logging.
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| 
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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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| 
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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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| 
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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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| 
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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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| 
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| @item -dframes number
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| Set the number of data frames to record.
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| 
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| @item -scodec codec
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| Force subtitle codec ('copy' to copy stream).
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| 
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| @item -newsubtitle
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| Add a new subtitle stream to the current output stream.
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| 
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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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| 
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| @end table
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| 
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| @section Video Options
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| 
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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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| 
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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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| 
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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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| 
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| @item -passlogfile file
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| Set two pass logfile name to @var{file}.
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| 
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| @item -newvideo
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| Add a new video stream to the current output stream.
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| 
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| @end table
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| 
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| @section Advanced Video Options
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| 
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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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| 
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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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| 
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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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| 
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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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| 
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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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| 
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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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| 
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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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| 
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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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| 
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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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| 
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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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| 
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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
 | |
| 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
 | |
| 
 | |
| @table @option
 | |
| @item -aframes number
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| Set the number of audio frames to record.
 | |
| @item -ar freq
 | |
| 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
 | |
| Set the number of audio channels (default = 1).
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| @item -an
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| 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.
 | |
| @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.
 | |
| 
 | |
| @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 (both floating-point and
 | |
| fixed-point mode) reference decoders and encoders.
 | |
| 
 | |
| @itemize
 | |
| 
 | |
| @item For AMR WB floating-point download TS26.204 V5.1.0 from
 | |
| @url{http://www.3gpp.org/ftp/Specs/archive/26_series/26.204/26204-510.zip}
 | |
| and extract the source to @file{libavcodec/amrwb_float/}.
 | |
| 
 | |
| @item For AMR NB floating-point download TS26.104 REL-5 V5.1.0 from
 | |
| @url{http://www.3gpp.org/ftp/Specs/archive/26_series/26.104/26104-510.zip}
 | |
| and extract the source to @file{libavcodec/amr_float/}.
 | |
| If you try this on Alpha, you may need to change @code{Word32} to
 | |
| @code{int} in @file{amr/typedef.h}.
 | |
| 
 | |
| @item For AMR NB fixed-point download TS26.073 REL-5 V5.1.0 from
 | |
| @url{http://www.3gpp.org/ftp/Specs/archive/26_series/26.073/26073-510.zip}
 | |
| and extract the source to @file{libavcodec/amr}.
 | |
| You must also add @code{-DMMS_IO} and remove @code{-pedantic-errors}
 | |
| to/from @code{CFLAGS} in @file{libavcodec/amr/makefile}, i.e.
 | |
| ``@code{CFLAGS = -Wall -I. \$(CFLAGS_\$(MODE)) -D\$(VAD) -DMMS_IO}''.
 | |
| 
 | |
| @end itemize
 | |
| 
 | |
| 
 | |
| @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    @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
 | |
| @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     @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     @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.
 | |
| @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      @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
 | |
| @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.
 | |
| 
 | |
| @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
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|    (#ifdef etc) by default so it does not interfere with other developers'
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|    work.
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| @item
 | |
|    You do not have to over-test things. If it works for you, and you think it
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|    should work for others, then commit. If your code has problems
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|    (portability, triggers compiler bugs, unusual environment etc) they will be
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|    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
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|    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
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|    ask/disscuss 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
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|    functionality from the code. Just improve!
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| 
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|    Note: Redundant code can be removed.
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| @item
 | |
|    Do not commit changes to the build system (Makefiles, configure script)
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|    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
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|    list, and if the code maintainers say OK, you may commit. This does not
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|    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
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|    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
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|    prefer if the indentation throughout FFmpeg was consistent (Many projects
 | |
|    force a given indentation style - we do not.). If you really need to make
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|    indentation changes (try to avoid this), separate them strictly from real
 | |
|    changes.
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| 
 | |
|    NOTE: If you had to put if()@{ .. @} over a large (> 5 lines) chunk of code,
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|    then either do NOT change the indentation of the inner part within (do not
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|    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
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|    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
 | |
|     Do NOT commit to code actively maintained by others without permission.
 | |
|     Send a patch to ffmpeg-devel instead. If noone 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.
 | |
| @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()')
 | |
| 
 | |
| @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 disscussion. 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
 |