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\input texinfo @c -*- texinfo -*-
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@settitle FFmpeg Documentation
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@titlepage
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@sp 7
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@center @titlefont{FFmpeg Documentation}
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@sp 3
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@end titlepage
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@chapter Synopsis
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The generic syntax is:
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@example
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@c man begin SYNOPSIS
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ffmpeg [[infile options][@option{-i} @var{infile}]]... @{[outfile options] @var{outfile}@}...
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@c man end
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@end example
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@chapter Description
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@c man begin DESCRIPTION
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FFmpeg is a very fast video and audio converter. It can also grab from
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a live audio/video source.
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The command line interface is designed to be intuitive, in the sense
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that FFmpeg tries to figure out all parameters that can possibly be
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derived automatically. You usually only have to specify the target
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bitrate you want.
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FFmpeg can also convert from any sample rate to any other, and resize
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video on the fly with a high quality polyphase filter.
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As a general rule, options are applied to the next specified
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file. Therefore, order is important, and you can have the same
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option on the command line multiple times. Each occurrence is
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then applied to the next input or output file.
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* To set the video bitrate of the output file to 64kbit/s:
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@example
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ffmpeg -i input.avi -b 64k output.avi
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@end example
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* To force the frame rate of the output file to 24 fps:
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@example
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ffmpeg -i input.avi -r 24 output.avi
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@end example
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* To force the frame rate of the input file (valid for raw formats only)
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to 1 fps and the frame rate of the output file to 24 fps:
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@example
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ffmpeg -r 1 -i input.m2v -r 24 output.avi
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@end example
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The format option may be needed for raw input files.
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By default, FFmpeg tries to convert as losslessly as possible: It
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uses the same audio and video parameters for the outputs as the one
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specified for the inputs.
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@c man end DESCRIPTION
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@chapter Options
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@c man begin OPTIONS
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@include fftools-common-opts.texi
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@section Main options
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@table @option
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@item -f @var{fmt}
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Force format.
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@item -i @var{filename}
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input file name
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@item -y
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Overwrite output files.
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@item -t @var{duration}
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Restrict the transcoded/captured video sequence
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to the duration specified in seconds.
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@code{hh:mm:ss[.xxx]} syntax is also supported.
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@item -fs @var{limit_size}
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Set the file size limit.
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@item -ss @var{position}
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Seek to given time position in seconds.
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@code{hh:mm:ss[.xxx]} syntax is also supported.
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@item -itsoffset @var{offset}
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Set the input time offset in seconds.
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@code{[-]hh:mm:ss[.xxx]} syntax is also supported.
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This option affects all the input files that follow it.
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The offset is added to the timestamps of the input files.
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Specifying a positive offset means that the corresponding
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streams are delayed by 'offset' seconds.
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@item -timestamp @var{time}
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Set the recording timestamp in the container.
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The syntax for @var{time} is:
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@example
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now|([(YYYY-MM-DD|YYYYMMDD)[T|t| ]]((HH[:MM[:SS[.m...]]])|(HH[MM[SS[.m...]]]))[Z|z])
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@end example
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If the value is "now" it takes the current time.
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Time is local time unless 'Z' or 'z' is appended, in which case it is
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interpreted as UTC.
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If the year-month-day part is not specified it takes the current
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year-month-day.
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@item -metadata @var{key}=@var{value}
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Set a metadata key/value pair.
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For example, for setting the title in the output file:
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@example
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ffmpeg -i in.avi -metadata title="my title" out.flv
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@end example
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@item -v @var{number}
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Set the logging verbosity level.
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@item -target @var{type}
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Specify target file type ("vcd", "svcd", "dvd", "dv", "dv50", "pal-vcd",
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"ntsc-svcd", ... ). All the format options (bitrate, codecs,
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buffer sizes) are then set automatically. You can just type:
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@example
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ffmpeg -i myfile.avi -target vcd /tmp/vcd.mpg
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@end example
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Nevertheless you can specify additional options as long as you know
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they do not conflict with the standard, as in:
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@example
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ffmpeg -i myfile.avi -target vcd -bf 2 /tmp/vcd.mpg
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@end example
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@item -dframes @var{number}
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Set the number of data frames to record.
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@item -scodec @var{codec}
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Force subtitle codec ('copy' to copy stream).
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@item -newsubtitle
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Add a new subtitle stream to the current output stream.
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@item -slang @var{code}
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Set the ISO 639 language code (3 letters) of the current subtitle stream.
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@end table
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@section Video Options
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@table @option
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@item -b @var{bitrate}
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Set the video bitrate in bit/s (default = 200 kb/s).
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@item -vframes @var{number}
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Set the number of video frames to record.
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@item -r @var{fps}
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Set frame rate (Hz value, fraction or abbreviation), (default = 25).
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@item -s @var{size}
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Set frame size. The format is @samp{wxh} (ffserver default = 160x128, ffmpeg default = same as source).
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The following abbreviations are recognized:
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@table @samp
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@item sqcif
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128x96
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@item qcif
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176x144
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@item cif
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352x288
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@item 4cif
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704x576
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@item 16cif
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1408x1152
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@item qqvga
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160x120
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@item qvga
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320x240
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@item vga
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640x480
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@item svga
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800x600
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@item xga
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1024x768
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@item uxga
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1600x1200
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@item qxga
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2048x1536
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@item sxga
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1280x1024
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@item qsxga
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2560x2048
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@item hsxga
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5120x4096
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@item wvga
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852x480
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@item wxga
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1366x768
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@item wsxga
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1600x1024
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@item wuxga
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1920x1200
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@item woxga
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2560x1600
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@item wqsxga
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3200x2048
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@item wquxga
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3840x2400
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@item whsxga
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6400x4096
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@item whuxga
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7680x4800
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@item cga
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320x200
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@item ega
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640x350
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@item hd480
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852x480
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@item hd720
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1280x720
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@item hd1080
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1920x1080
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@end table
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@item -aspect @var{aspect}
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Set aspect ratio (4:3, 16:9 or 1.3333, 1.7777).
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@item -croptop @var{size}
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@item -cropbottom @var{size}
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@item -cropleft @var{size}
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@item -cropright @var{size}
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All the crop options have been removed. Use -vf
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crop=width:height:x:y instead.
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@item -padtop @var{size}
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@item -padbottom @var{size}
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@item -padleft @var{size}
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@item -padright @var{size}
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@item -padcolor @var{hex_color}
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All the pad options have been removed. Use -vf
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pad=width:height:x:y:color instead.
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@item -vn
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Disable video recording.
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@item -bt @var{tolerance}
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Set video bitrate tolerance (in bits, default 4000k).
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Has a minimum value of: (target_bitrate/target_framerate).
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In 1-pass mode, bitrate tolerance specifies how far ratecontrol is
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willing to deviate from the target average bitrate value. This is
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not related to min/max bitrate. Lowering tolerance too much has
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an adverse effect on quality.
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@item -maxrate @var{bitrate}
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Set max video bitrate (in bit/s).
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Requires -bufsize to be set.
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@item -minrate @var{bitrate}
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Set min video bitrate (in bit/s).
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Most useful in setting up a CBR encode:
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@example
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ffmpeg -i myfile.avi -b 4000k -minrate 4000k -maxrate 4000k -bufsize 1835k out.m2v
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@end example
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It is of little use elsewise.
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@item -bufsize @var{size}
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Set video buffer verifier buffer size (in bits).
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@item -vcodec @var{codec}
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Force video codec to @var{codec}. Use the @code{copy} special value to
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tell that the raw codec data must be copied as is.
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@item -sameq
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Use same video quality as source (implies VBR).
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@item -pass @var{n}
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Select the pass number (1 or 2). It is used to do two-pass
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video encoding. The statistics of the video are recorded in the first
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pass into a log file (see also the option -passlogfile),
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and in the second pass that log file is used to generate the video
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at the exact requested bitrate.
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On pass 1, you may just deactivate audio and set output to null,
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examples for Windows and Unix:
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@example
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ffmpeg -i foo.mov -vcodec libxvid -pass 1 -an -f rawvideo -y NUL
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ffmpeg -i foo.mov -vcodec libxvid -pass 1 -an -f rawvideo -y /dev/null
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@end example
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@item -passlogfile @var{prefix}
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Set two-pass log file name prefix to @var{prefix}, the default file name
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prefix is ``ffmpeg2pass''. The complete file name will be
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@file{PREFIX-N.log}, where N is a number specific to the output
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stream.
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@item -newvideo
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Add a new video stream to the current output stream.
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@item -vlang @var{code}
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Set the ISO 639 language code (3 letters) of the current video stream.
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@item -vf @var{filter_graph}
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@var{filter_graph} is a description of the filter graph to apply to
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the input video.
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Use the option "-filters" to show all the available filters (including
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also sources and sinks).
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@end table
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@section Advanced Video Options
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@table @option
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@item -pix_fmt @var{format}
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Set pixel format. Use 'list' as parameter to show all the supported
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pixel formats.
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@item -sws_flags @var{flags}
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Set SwScaler flags.
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@item -g @var{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 @var{n}
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Discard threshold.
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@item -qscale @var{q}
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Use fixed video quantizer scale (VBR).
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@item -qmin @var{q}
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minimum video quantizer scale (VBR)
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@item -qmax @var{q}
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maximum video quantizer scale (VBR)
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@item -qdiff @var{q}
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maximum difference between the quantizer scales (VBR)
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@item -qblur @var{blur}
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video quantizer scale blur (VBR) (range 0.0 - 1.0)
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@item -qcomp @var{compression}
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video quantizer scale compression (VBR) (default 0.5).
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Constant of ratecontrol equation. Recommended range for default rc_eq: 0.0-1.0
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@item -lmin @var{lambda}
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minimum video lagrange factor (VBR)
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@item -lmax @var{lambda}
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max video lagrange factor (VBR)
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@item -mblmin @var{lambda}
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minimum macroblock quantizer scale (VBR)
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@item -mblmax @var{lambda}
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maximum macroblock quantizer scale (VBR)
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These four options (lmin, lmax, mblmin, mblmax) use 'lambda' units,
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but you may use the QP2LAMBDA constant to easily convert from 'q' units:
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@example
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ffmpeg -i src.ext -lmax 21*QP2LAMBDA dst.ext
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@end example
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@item -rc_init_cplx @var{complexity}
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initial complexity for single pass encoding
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@item -b_qfactor @var{factor}
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qp factor between P- and B-frames
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@item -i_qfactor @var{factor}
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qp factor between P- and I-frames
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@item -b_qoffset @var{offset}
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qp offset between P- and B-frames
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@item -i_qoffset @var{offset}
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qp offset between P- and I-frames
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@item -rc_eq @var{equation}
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Set rate control equation (see section "Expression Evaluation")
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(default = @code{tex^qComp}).
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When computing the rate control equation expression, besides the
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standard functions defined in the section "Expression Evaluation", the
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following functions are available:
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@table @var
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@item bits2qp(bits)
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@item qp2bits(qp)
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@end table
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and the following constants are available:
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@table @var
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@item iTex
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@item pTex
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@item tex
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@item mv
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@item fCode
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@item iCount
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@item mcVar
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@item var
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@item isI
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@item isP
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@item isB
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@item avgQP
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@item qComp
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@item avgIITex
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@item avgPITex
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@item avgPPTex
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@item avgBPTex
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@item avgTex
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@end table
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@item -rc_override @var{override}
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rate control override for specific intervals
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@item -me_method @var{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 hex
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@item umh
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@item epzs
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(default method)
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@item full
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exhaustive search (slow and marginally better than epzs)
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@end table
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@item -dct_algo @var{algo}
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Set DCT algorithm to @var{algo}. Available values are:
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@table @samp
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@item 0
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FF_DCT_AUTO (default)
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@item 1
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FF_DCT_FASTINT
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@item 2
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FF_DCT_INT
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@item 3
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FF_DCT_MMX
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@item 4
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FF_DCT_MLIB
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@item 5
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FF_DCT_ALTIVEC
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@end table
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@item -idct_algo @var{algo}
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Set IDCT algorithm to @var{algo}. Available values are:
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@table @samp
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@item 0
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FF_IDCT_AUTO (default)
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@item 1
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FF_IDCT_INT
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@item 2
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FF_IDCT_SIMPLE
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@item 3
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FF_IDCT_SIMPLEMMX
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@item 4
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FF_IDCT_LIBMPEG2MMX
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@item 5
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FF_IDCT_PS2
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@item 6
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FF_IDCT_MLIB
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@item 7
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FF_IDCT_ARM
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@item 8
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FF_IDCT_ALTIVEC
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@item 9
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FF_IDCT_SH4
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@item 10
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FF_IDCT_SIMPLEARM
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@end table
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@item -er @var{n}
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Set error resilience to @var{n}.
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@table @samp
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@item 1
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FF_ER_CAREFUL (default)
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@item 2
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FF_ER_COMPLIANT
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@item 3
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FF_ER_AGGRESSIVE
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@item 4
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FF_ER_VERY_AGGRESSIVE
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@end table
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@item -ec @var{bit_mask}
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Set error concealment to @var{bit_mask}. @var{bit_mask} is a bit mask of
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the following values:
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@table @samp
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@item 1
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FF_EC_GUESS_MVS (default = enabled)
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@item 2
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FF_EC_DEBLOCK (default = enabled)
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@end table
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@item -bf @var{frames}
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Use 'frames' B-frames (supported for MPEG-1, MPEG-2 and MPEG-4).
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@item -mbd @var{mode}
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macroblock decision
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@table @samp
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@item 0
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FF_MB_DECISION_SIMPLE: Use mb_cmp (cannot change it yet in FFmpeg).
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@item 1
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FF_MB_DECISION_BITS: Choose the one which needs the fewest bits.
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@item 2
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FF_MB_DECISION_RD: rate distortion
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@end table
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@item -4mv
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Use four motion vector by macroblock (MPEG-4 only).
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@item -part
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Use data partitioning (MPEG-4 only).
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@item -bug @var{param}
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Work around encoder bugs that are not auto-detected.
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@item -strict @var{strictness}
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How strictly to follow the standards.
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@item -aic
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Enable Advanced intra coding (h263+).
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@item -umv
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Enable Unlimited Motion Vector (h263+)
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@item -deinterlace
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Deinterlace pictures.
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@item -ilme
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Force interlacing support in encoder (MPEG-2 and MPEG-4 only).
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Use this option if your input file is interlaced and you want
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to keep the interlaced format for minimum losses.
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The alternative is to deinterlace the input stream with
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@option{-deinterlace}, but deinterlacing introduces losses.
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@item -psnr
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Calculate PSNR of compressed frames.
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@item -vstats
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Dump video coding statistics to @file{vstats_HHMMSS.log}.
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@item -vstats_file @var{file}
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Dump video coding statistics to @var{file}.
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@item -top @var{n}
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top=1/bottom=0/auto=-1 field first
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@item -dc @var{precision}
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Intra_dc_precision.
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@item -vtag @var{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 @var{bitstream_filter}
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Bitstream filters available are "dump_extra", "remove_extra", "noise", "h264_mp4toannexb", "imxdump", "mjpegadump", "mjpeg2jpeg".
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@example
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ffmpeg -i h264.mp4 -vcodec copy -vbsf h264_mp4toannexb -an out.h264
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@end example
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@item -force_key_frames @var{time}[,@var{time}...]
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Force key frames at the specified timestamps, more precisely at the first
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frames after each specified time.
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This option can be useful to ensure that a seek point is present at a
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chapter mark or any other designated place in the output file.
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The timestamps must be specified in ascending order.
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@end table
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@section Audio Options
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@table @option
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@item -aframes @var{number}
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Set the number of audio frames to record.
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@item -ar @var{freq}
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Set the audio sampling frequency. For input streams it is set by
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default to 44100 Hz, for output streams it is set by default to the
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frequency of the input stream. If the input file has audio streams
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with different frequencies, the behaviour is undefined.
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@item -ab @var{bitrate}
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Set the audio bitrate in bit/s (default = 64k).
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@item -aq @var{q}
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Set the audio quality (codec-specific, VBR).
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@item -ac @var{channels}
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Set the number of audio channels. For input streams it is set by
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default to 1, for output streams it is set by default to the same
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number of audio channels in input. If the input file has audio streams
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with different channel count, the behaviour is undefined.
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@item -an
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Disable audio recording.
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@item -acodec @var{codec}
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Force audio codec to @var{codec}. Use the @code{copy} special value to
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specify that the raw codec data must be copied as is.
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@item -newaudio
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Add a new audio track to the output file. If you want to specify parameters,
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do so before @code{-newaudio} (@code{-acodec}, @code{-ab}, etc..).
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Mapping will be done automatically, if the number of output streams is equal to
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the number of input streams, else it will pick the first one that matches. You
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can override the mapping using @code{-map} as usual.
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Example:
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@example
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ffmpeg -i file.mpg -vcodec copy -acodec ac3 -ab 384k test.mpg -acodec mp2 -ab 192k -newaudio
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@end example
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@item -alang @var{code}
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Set the ISO 639 language code (3 letters) of the current audio stream.
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@end table
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@section Advanced Audio options:
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@table @option
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@item -atag @var{fourcc/tag}
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Force audio tag/fourcc.
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@item -absf @var{bitstream_filter}
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Bitstream filters available are "dump_extra", "remove_extra", "noise", "mp3comp", "mp3decomp".
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@end table
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@section Subtitle options:
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@table @option
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@item -scodec @var{codec}
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Force subtitle codec ('copy' to copy stream).
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@item -newsubtitle
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Add a new subtitle stream to the current output stream.
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@item -slang @var{code}
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Set the ISO 639 language code (3 letters) of the current subtitle stream.
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@item -sn
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Disable subtitle recording.
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@item -sbsf @var{bitstream_filter}
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Bitstream filters available are "mov2textsub", "text2movsub".
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@example
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ffmpeg -i file.mov -an -vn -sbsf mov2textsub -scodec copy -f rawvideo sub.txt
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@end example
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@end table
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@section Audio/Video grab options
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@table @option
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@item -vc @var{channel}
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Set video grab channel (DV1394 only).
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@item -tvstd @var{standard}
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Set television standard (NTSC, PAL (SECAM)).
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@item -isync
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Synchronize read on input.
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@end table
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@section Advanced options
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@table @option
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@item -map @var{input_stream_id}[:@var{sync_stream_id}]
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Set stream mapping from input streams to output streams.
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Just enumerate the input streams in the order you want them in the output.
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@var{sync_stream_id} if specified sets the input stream to sync
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against.
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@item -map_meta_data @var{outfile}[,@var{metadata}]:@var{infile}[,@var{metadata}]
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Set meta data information of @var{outfile} from @var{infile}. Note that those
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are file indices (zero-based), not filenames.
626
Optional @var{metadata} parameters specify, which metadata to copy - (g)lobal
627
(i.e. metadata that applies to the whole file), per-(s)tream, per-(c)hapter or
628
per-(p)rogram. All metadata specifiers other than global must be followed by the
629
stream/chapter/program number. If metadata specifier is omitted, it defaults to
630
global.
631

    
632
By default, global metadata is copied from the first input file to all output files,
633
per-stream and per-chapter metadata is copied along with streams/chapters. These
634
default mappings are disabled by creating any mapping of the relevant type. A negative
635
file index can be used to create a dummy mapping that just disables automatic copying.
636

    
637
For example to copy metadata from the first stream of the input file to global metadata
638
of the output file:
639
@example
640
ffmpeg -i in.ogg -map_meta_data 0:0,s0 out.mp3
641
@end example
642
@item -map_chapters @var{outfile}:@var{infile}
643
Copy chapters from @var{infile} to @var{outfile}. If no chapter mapping is specified,
644
then chapters are copied from the first input file with at least one chapter to all
645
output files. Use a negative file index to disable any chapter copying.
646
@item -debug
647
Print specific debug info.
648
@item -benchmark
649
Show benchmarking information at the end of an encode.
650
Shows CPU time used and maximum memory consumption.
651
Maximum memory consumption is not supported on all systems,
652
it will usually display as 0 if not supported.
653
@item -dump
654
Dump each input packet.
655
@item -hex
656
When dumping packets, also dump the payload.
657
@item -bitexact
658
Only use bit exact algorithms (for codec testing).
659
@item -ps @var{size}
660
Set RTP payload size in bytes.
661
@item -re
662
Read input at native frame rate. Mainly used to simulate a grab device.
663
@item -loop_input
664
Loop over the input stream. Currently it works only for image
665
streams. This option is used for automatic FFserver testing.
666
@item -loop_output @var{number_of_times}
667
Repeatedly loop output for formats that support looping such as animated GIF
668
(0 will loop the output infinitely).
669
@item -threads @var{count}
670
Thread count.
671
@item -vsync @var{parameter}
672
Video sync method.
673
0   Each frame is passed with its timestamp from the demuxer to the muxer
674
1   Frames will be duplicated and dropped to achieve exactly the requested
675
    constant framerate.
676
2   Frames are passed through with their timestamp or dropped so as to prevent
677
    2 frames from having the same timestamp
678
-1  Chooses between 1 and 2 depending on muxer capabilities. This is the default method.
679

    
680
With -map you can select from
681
which stream the timestamps should be taken. You can leave either video or
682
audio unchanged and sync the remaining stream(s) to the unchanged one.
683
@item -async @var{samples_per_second}
684
Audio sync method. "Stretches/squeezes" the audio stream to match the timestamps,
685
the parameter is the maximum samples per second by which the audio is changed.
686
-async 1 is a special case where only the start of the audio stream is corrected
687
without any later correction.
688
@item -copyts
689
Copy timestamps from input to output.
690
@item -copytb
691
Copy input stream time base from input to output when stream copying.
692
@item -shortest
693
Finish encoding when the shortest input stream ends.
694
@item -dts_delta_threshold
695
Timestamp discontinuity delta threshold.
696
@item -muxdelay @var{seconds}
697
Set the maximum demux-decode delay.
698
@item -muxpreload @var{seconds}
699
Set the initial demux-decode delay.
700
@item -streamid @var{output-stream-index}:@var{new-value}
701
Assign a new value to a stream's stream-id field in the next output file.
702
All stream-id fields are reset to default for each output file.
703

    
704
For example, to set the stream 0 PID to 33 and the stream 1 PID to 36 for
705
an output mpegts file:
706
@example
707
ffmpeg -i infile -streamid 0:33 -streamid 1:36 out.ts
708
@end example
709
@end table
710

    
711
@section Preset files
712

    
713
A preset file contains a sequence of @var{option}=@var{value} pairs,
714
one for each line, specifying a sequence of options which would be
715
awkward to specify on the command line. Lines starting with the hash
716
('#') character are ignored and are used to provide comments. Check
717
the @file{ffpresets} directory in the FFmpeg source tree for examples.
718

    
719
Preset files are specified with the @code{vpre}, @code{apre},
720
@code{spre}, and @code{fpre} options. The @code{fpre} option takes the
721
filename of the preset instead of a preset name as input and can be
722
used for any kind of codec. For the @code{vpre}, @code{apre}, and
723
@code{spre} options, the options specified in a preset file are
724
applied to the currently selected codec of the same type as the preset
725
option.
726

    
727
The argument passed to the @code{vpre}, @code{apre}, and @code{spre}
728
preset options identifies the preset file to use according to the
729
following rules:
730

    
731
First ffmpeg searches for a file named @var{arg}.ffpreset in the
732
directories @file{$FFMPEG_DATADIR} (if set), and @file{$HOME/.ffmpeg}, and in
733
the datadir defined at configuration time (usually @file{PREFIX/share/ffmpeg})
734
in that order. For example, if the argument is @code{libx264-max}, it will
735
search for the file @file{libx264-max.ffpreset}.
736

    
737
If no such file is found, then ffmpeg will search for a file named
738
@var{codec_name}-@var{arg}.ffpreset in the above-mentioned
739
directories, where @var{codec_name} is the name of the codec to which
740
the preset file options will be applied. For example, if you select
741
the video codec with @code{-vcodec libx264} and use @code{-vpre max},
742
then it will search for the file @file{libx264-max.ffpreset}.
743
@c man end
744

    
745
@chapter Tips
746
@c man begin TIPS
747

    
748
@itemize
749
@item
750
For streaming at very low bitrate application, use a low frame rate
751
and a small GOP size. This is especially true for RealVideo where
752
the Linux player does not seem to be very fast, so it can miss
753
frames. An example is:
754

    
755
@example
756
ffmpeg -g 3 -r 3 -t 10 -b 50k -s qcif -f rv10 /tmp/b.rm
757
@end example
758

    
759
@item
760
The parameter 'q' which is displayed while encoding is the current
761
quantizer. The value 1 indicates that a very good quality could
762
be achieved. The value 31 indicates the worst quality. If q=31 appears
763
too often, it means that the encoder cannot compress enough to meet
764
your bitrate. You must either increase the bitrate, decrease the
765
frame rate or decrease the frame size.
766

    
767
@item
768
If your computer is not fast enough, you can speed up the
769
compression at the expense of the compression ratio. You can use
770
'-me zero' to speed up motion estimation, and '-intra' to disable
771
motion estimation completely (you have only I-frames, which means it
772
is about as good as JPEG compression).
773

    
774
@item
775
To have very low audio bitrates, reduce the sampling frequency
776
(down to 22050 Hz for MPEG audio, 22050 or 11025 for AC-3).
777

    
778
@item
779
To have a constant quality (but a variable bitrate), use the option
780
'-qscale n' when 'n' is between 1 (excellent quality) and 31 (worst
781
quality).
782

    
783
@item
784
When converting video files, you can use the '-sameq' option which
785
uses the same quality factor in the encoder as in the decoder.
786
It allows almost lossless encoding.
787

    
788
@end itemize
789
@c man end TIPS
790

    
791
@chapter Examples
792
@c man begin EXAMPLES
793

    
794
@section Video and Audio grabbing
795

    
796
FFmpeg can grab video and audio from devices given that you specify the input
797
format and device.
798

    
799
@example
800
ffmpeg -f oss -i /dev/dsp -f video4linux2 -i /dev/video0 /tmp/out.mpg
801
@end example
802

    
803
Note that you must activate the right video source and channel before
804
launching FFmpeg with any TV viewer such as xawtv
805
(@url{http://linux.bytesex.org/xawtv/}) by Gerd Knorr. You also
806
have to set the audio recording levels correctly with a
807
standard mixer.
808

    
809
@section X11 grabbing
810

    
811
FFmpeg can grab the X11 display.
812

    
813
@example
814
ffmpeg -f x11grab -s cif -r 25 -i :0.0 /tmp/out.mpg
815
@end example
816

    
817
0.0 is display.screen number of your X11 server, same as
818
the DISPLAY environment variable.
819

    
820
@example
821
ffmpeg -f x11grab -s cif -r 25 -i :0.0+10,20 /tmp/out.mpg
822
@end example
823

    
824
0.0 is display.screen number of your X11 server, same as the DISPLAY environment
825
variable. 10 is the x-offset and 20 the y-offset for the grabbing.
826

    
827
@section Video and Audio file format conversion
828

    
829
* FFmpeg can use any supported file format and protocol as input:
830

    
831
Examples:
832

    
833
* You can use YUV files as input:
834

    
835
@example
836
ffmpeg -i /tmp/test%d.Y /tmp/out.mpg
837
@end example
838

    
839
It will use the files:
840
@example
841
/tmp/test0.Y, /tmp/test0.U, /tmp/test0.V,
842
/tmp/test1.Y, /tmp/test1.U, /tmp/test1.V, etc...
843
@end example
844

    
845
The Y files use twice the resolution of the U and V files. They are
846
raw files, without header. They can be generated by all decent video
847
decoders. You must specify the size of the image with the @option{-s} option
848
if FFmpeg cannot guess it.
849

    
850
* You can input from a raw YUV420P file:
851

    
852
@example
853
ffmpeg -i /tmp/test.yuv /tmp/out.avi
854
@end example
855

    
856
test.yuv is a file containing raw YUV planar data. Each frame is composed
857
of the Y plane followed by the U and V planes at half vertical and
858
horizontal resolution.
859

    
860
* You can output to a raw YUV420P file:
861

    
862
@example
863
ffmpeg -i mydivx.avi hugefile.yuv
864
@end example
865

    
866
* You can set several input files and output files:
867

    
868
@example
869
ffmpeg -i /tmp/a.wav -s 640x480 -i /tmp/a.yuv /tmp/a.mpg
870
@end example
871

    
872
Converts the audio file a.wav and the raw YUV video file a.yuv
873
to MPEG file a.mpg.
874

    
875
* You can also do audio and video conversions at the same time:
876

    
877
@example
878
ffmpeg -i /tmp/a.wav -ar 22050 /tmp/a.mp2
879
@end example
880

    
881
Converts a.wav to MPEG audio at 22050 Hz sample rate.
882

    
883
* You can encode to several formats at the same time and define a
884
mapping from input stream to output streams:
885

    
886
@example
887
ffmpeg -i /tmp/a.wav -ab 64k /tmp/a.mp2 -ab 128k /tmp/b.mp2 -map 0:0 -map 0:0
888
@end example
889

    
890
Converts a.wav to a.mp2 at 64 kbits and to b.mp2 at 128 kbits. '-map
891
file:index' specifies which input stream is used for each output
892
stream, in the order of the definition of output streams.
893

    
894
* You can transcode decrypted VOBs:
895

    
896
@example
897
ffmpeg -i snatch_1.vob -f avi -vcodec mpeg4 -b 800k -g 300 -bf 2 -acodec libmp3lame -ab 128k snatch.avi
898
@end example
899

    
900
This is a typical DVD ripping example; the input is a VOB file, the
901
output an AVI file with MPEG-4 video and MP3 audio. Note that in this
902
command we use B-frames so the MPEG-4 stream is DivX5 compatible, and
903
GOP size is 300 which means one intra frame every 10 seconds for 29.97fps
904
input video. Furthermore, the audio stream is MP3-encoded so you need
905
to enable LAME support by passing @code{--enable-libmp3lame} to configure.
906
The mapping is particularly useful for DVD transcoding
907
to get the desired audio language.
908

    
909
NOTE: To see the supported input formats, use @code{ffmpeg -formats}.
910

    
911
* You can extract images from a video, or create a video from many images:
912

    
913
For extracting images from a video:
914
@example
915
ffmpeg -i foo.avi -r 1 -s WxH -f image2 foo-%03d.jpeg
916
@end example
917

    
918
This will extract one video frame per second from the video and will
919
output them in files named @file{foo-001.jpeg}, @file{foo-002.jpeg},
920
etc. Images will be rescaled to fit the new WxH values.
921

    
922
If you want to extract just a limited number of frames, you can use the
923
above command in combination with the -vframes or -t option, or in
924
combination with -ss to start extracting from a certain point in time.
925

    
926
For creating a video from many images:
927
@example
928
ffmpeg -f image2 -i foo-%03d.jpeg -r 12 -s WxH foo.avi
929
@end example
930

    
931
The syntax @code{foo-%03d.jpeg} specifies to use a decimal number
932
composed of three digits padded with zeroes to express the sequence
933
number. It is the same syntax supported by the C printf function, but
934
only formats accepting a normal integer are suitable.
935

    
936
* You can put many streams of the same type in the output:
937

    
938
@example
939
ffmpeg -i test1.avi -i test2.avi -vcodec copy -acodec copy -vcodec copy -acodec copy test12.avi -newvideo -newaudio
940
@end example
941

    
942
In addition to the first video and audio streams, the resulting
943
output file @file{test12.avi} will contain the second video
944
and the second audio stream found in the input streams list.
945

    
946
The @code{-newvideo}, @code{-newaudio} and @code{-newsubtitle}
947
options have to be specified immediately after the name of the output
948
file to which you want to add them.
949
@c man end EXAMPLES
950

    
951
@include eval.texi
952
@include demuxers.texi
953
@include indevs.texi
954
@include outdevs.texi
955
@include protocols.texi
956
@include bitstream_filters.texi
957
@include filters.texi
958
@include metadata.texi
959

    
960
@ignore
961

    
962
@setfilename ffmpeg
963
@settitle FFmpeg video converter
964

    
965
@c man begin SEEALSO
966
ffplay(1), ffprobe(1), ffserver(1) and the FFmpeg HTML documentation
967
@c man end
968

    
969
@c man begin AUTHORS
970
The FFmpeg developers
971
@c man end
972

    
973
@end ignore
974

    
975
@bye