a live audio/video source. It can also convert between arbitrary sample
rates and resize video on the fly with a high quality polyphase filter.
+ffmpeg reads from an arbitrary number of input "files" (which can be regular
+files, pipes, network streams, grabbing devices, etc.), specified by the
+@code{-i} option, and writes to an arbitrary number of output "files", which are
+specified by a plain output filename. Anything found on the commandline which
+cannot be interpreted as an option is considered to be an output filename.
+
+Each input or output file can in principle contain any number of streams of
+different types (video/audio/subtitle/attachment/data). Allowed number and/or
+types of streams can be limited by the container format. Selecting, which
+streams from which inputs go into output, is done either automatically or with
+the @code{-map} option (see the Stream selection chapter).
+
+To refer to input files in options, you must use their indices (0-based). E.g.
+the first input file is @code{0}, the second is @code{1} etc. Similarly, streams
+within a file are referred to by their indices. E.g. @code{2:3} refers to the
+fourth stream in the third input file. See also the Stream specifiers chapter.
+
As a general rule, options are applied to the next specified
file. Therefore, order is important, and you can have the same
option on the command line multiple times. Each occurrence is
Exceptions from this rule are the global options (e.g. verbosity level),
which should be specified first.
+Do not mix input and output files -- first specify all input files, then all
+output files. Also do not mix options which belong to different files. All
+options apply ONLY to the next input or output file and are reset between files.
+
@itemize
@item
To set the video bitrate of the output file to 64kbit/s:
@example
-ffmpeg -i input.avi -b 64k output.avi
+ffmpeg -i input.avi -b:v 64k output.avi
@end example
@item
@chapter Stream selection
@c man begin STREAM SELECTION
-By default ffmpeg tries to pick the "best" stream of each type present in input
-files and add them to each output file. For video, this means the highest
-resolution, for audio the highest channel count. For subtitle it's simply the
-first subtitle stream.
+By default ffmpeg includes only one stream of each type (video, audio, subtitle)
+present in the input files and adds them to each output file. It picks the
+"best" of each based upon the following criteria; for video it is the stream
+with the highest resolution, for audio the stream with the most channels, for
+subtitle it's the first subtitle stream. In the case where several streams of
+the same type rate equally, the lowest numbered stream is chosen.
You can disable some of those defaults by using @code{-vn/-an/-sn} options. For
full manual control, use the @code{-map} option, which disables the defaults just
@table @option
@item -f @var{fmt} (@emph{input/output})
-Force input or output file format. The format is normally autodetected for input
+Force input or output file format. The format is normally auto detected for input
files and guessed from file extension for output files, so this option is not
needed in most cases.
@item -y (@emph{global})
Overwrite output files without asking.
+@item -n (@emph{global})
+Do not overwrite output files but exit if file exists.
+
@item -c[:@var{stream_specifier}] @var{codec} (@emph{input/output,per-stream})
@itemx -codec[:@var{stream_specifier}] @var{codec} (@emph{input/output,per-stream})
Select an encoder (when used before an output file) or a decoder (when used
before an input file) for one or more streams. @var{codec} is the name of a
decoder/encoder or a special value @code{copy} (output only) to indicate that
-the stream is not to be reencoded.
+the stream is not to be re-encoded.
For example
@example
ffmpeg -i INPUT -metadata:s:1 language=eng OUTPUT
@end example
-@item -v @var{number} (@emph{global})
-This option is deprecated and has no effect, use -loglevel
-to set verbosity level.
-
@item -target @var{type} (@emph{output})
Specify target file type (@code{vcd}, @code{svcd}, @code{dvd}, @code{dv},
@code{dv50}). @var{type} may be prefixed with @code{pal-}, @code{ntsc-} or
Use fixed quality scale (VBR). The meaning of @var{q} is
codec-dependent.
-@item -filter[:@var{stream_specifier}] @var{filter_graph}
+@item -filter[:@var{stream_specifier}] @var{filter_graph} (@emph{output,per-stream})
@var{filter_graph} is a description of the filter graph to apply to
the stream. Use @code{-filters} to show all the available filters
(including also sources and sinks).
+@item -pre[:@var{stream_specifier}] @var{preset_name} (@emph{output,per-stream})
+Specify the preset for matching stream(s).
+
+@item -stats (@emph{global})
+Print encoding progress/statistics. On by default.
+
+@item -attach @var{filename} (@emph{output})
+Add an attachment to the output file. This is supported by a few formats
+like Matroska for e.g. fonts used in rendering subtitles. Attachments
+are implemented as a specific type of stream, so this option will add
+a new stream to the file. It is then possible to use per-stream options
+on this stream in the usual way. Attachment streams created with this
+option will be created after all the other streams (i.e. those created
+with @code{-map} or automatic mappings).
+
+Note that for Matroska you also have to set the mimetype metadata tag:
+@example
+ffmpeg -i INPUT -attach DejaVuSans.ttf -metadata:s:2 mimetype=application/x-truetype-font out.mkv
+@end example
+(assuming that the attachment stream will be third in the output file).
+
+@item -dump_attachment[:@var{stream_specifier}] @var{filename} (@emph{input,per-stream})
+Extract the matching attachment stream into a file named @var{filename}. If
+@var{filename} is empty, then the value of the @code{filename} metadata tag
+will be used.
+
+E.g. to extract the first attachment to a file named 'out.ttf':
+@example
+ffmpeg -dump_attachment:t:0 out.ttf INPUT
+@end example
+To extract all attachments to files determined by the @code{filename} tag:
+@example
+ffmpeg -dump_attachment:t "" INPUT
+@end example
+
+Technical note -- attachments are implemented as codec extradata, so this
+option can actually be used to extract extradata from any stream, not just
+attachments.
@end table
@item -r[:@var{stream_specifier}] @var{fps} (@emph{input/output,per-stream})
Set frame rate (Hz value, fraction or abbreviation), (default = 25).
@item -s[:@var{stream_specifier}] @var{size} (@emph{input/output,per-stream})
-Set frame size. The format is @samp{wxh} (ffserver default = 160x128, ffmpeg default = same as source).
+Set frame size. The format is @samp{wxh} (default - same as source).
The following abbreviations are recognized:
@table @samp
@item sqcif
Set min video bitrate (in bit/s).
Most useful in setting up a CBR encode:
@example
-ffmpeg -i myfile.avi -b 4000k -minrate 4000k -maxrate 4000k -bufsize 1835k out.m2v
+ffmpeg -i myfile.avi -b:v 4000k -minrate 4000k -maxrate 4000k -bufsize 1835k out.m2v
@end example
It is of little use elsewise.
@item -bufsize @var{size}
@end table
@item -rc_override[:@var{stream_specifier}] @var{override} (@emph{output,per-stream})
-Rate control override for specific intervals, formated as "int,int,int"
+Rate control override for specific intervals, formatted as "int,int,int"
list separated with slashes. Two first values are the beginning and
end frame numbers, last one is quantizer to use if positive, or quality
factor if negative.
This option can be useful to ensure that a seek point is present at a
chapter mark or any other designated place in the output file.
The timestamps must be specified in ascending order.
+
+@item -copyinkf[:@var{stream_specifier}] (@emph{output,per-stream})
+When doing stream copy, copy also non-key frames found at the
+beginning.
@end table
@section Audio Options
@item -acodec @var{codec} (@emph{input/output})
Set the audio codec. This is an alias for @code{-codec:a}.
@item -sample_fmt[:@var{stream_specifier}] @var{sample_fmt} (@emph{output,per-stream})
-Set the audio sample format. Use @code{-help sample_fmts} to get a list
+Set the audio sample format. Use @code{-sample_fmts} to get a list
of supported sample formats.
@end table
Note that using this option disables the default mappings for this output file.
+@item -map_channel [@var{input_file_id}.@var{stream_specifier}.@var{channel_id}|-1][:@var{output_file_id}.@var{stream_specifier}]
+Map an audio channel from a given input to an output. If
+@var{output_file_id}.@var{stream_specifier} are not set, the audio channel will
+be mapped on all the audio streams.
+
+Using "-1" instead of
+@var{input_file_id}.@var{stream_specifier}.@var{channel_id} will map a muted
+channel.
+
+For example, assuming @var{INPUT} is a stereo audio file, you can switch the
+two audio channels with the following command:
+@example
+ffmpeg -i INPUT -map_channel 0.0.1 -map_channel 0.0.0 OUTPUT
+@end example
+
+If you want to mute the first channel and keep the second:
+@example
+ffmpeg -i INPUT -map_channel -1 -map_channel 0.0.1 OUTPUT
+@end example
+
+The order of the "-map_channel" option specifies the order of the channels in
+the output stream. The output channel layout is guessed from the number of
+channels mapped (mono if one "-map_channel", stereo if two, etc.). Using "-ac"
+in combination of "-map_channel" makes the channel gain levels to be updated if
+channel layouts don't match (for instance two "-map_channel" options and "-ac
+6").
+
+You can also extract each channel of an @var{INPUT} to specific outputs; the
+following command extract each channel of the audio stream (file 0, stream 0)
+to the respective @var{OUTPUT_CH0} and @var{OUTPUT_CH1}:
+@example
+ffmpeg -i INPUT -map_channel 0.0.0 OUTPUT_CH0 -map_channel 0.0.1 OUTPUT_CH1
+@end example
+
+The following example split the channels of a stereo input into streams:
+
+@example
+ffmpeg -i stereo.wav -map 0:0 -map 0:0 -map_channel 0.0.0:0.0 -map_channel 0.0.1:0.1 -y out.ogg
+@end example
+
+Note that "-map_channel" is currently limited to the scope of one input for
+each output; you can't for example use it to pick multiple input audio files
+and mix them into one single output.
+
@item -map_metadata[:@var{metadata_type}][:@var{index}] @var{infile}[:@var{metadata_type}][:@var{index}] (@emph{output,per-metadata})
Set metadata information of the next output file from @var{infile}. Note that
those are file indices (zero-based), not filenames.
frames. An example is:
@example
-ffmpeg -g 3 -r 3 -t 10 -b 50k -s qcif -f rv10 /tmp/b.rm
+ffmpeg -g 3 -r 3 -t 10 -b:v 50k -s qcif -f rv10 /tmp/b.rm
@end example
@item
@chapter Examples
@c man begin EXAMPLES
+@section Preset files
+
+A preset file contains a sequence of @var{option=value} pairs, one for
+each line, specifying a sequence of options which can be specified also on
+the command line. Lines starting with the hash ('#') character are ignored and
+are used to provide comments. Empty lines are also ignored. Check the
+@file{presets} directory in the FFmpeg source tree for examples.
+
+Preset files are specified with the @code{pre} option, this option takes a
+preset name as input. FFmpeg searches for a file named @var{preset_name}.avpreset in
+the directories @file{$AVCONV_DATADIR} (if set), and @file{$HOME/.ffmpeg}, and in
+the data directory defined at configuration time (usually @file{$PREFIX/share/ffmpeg})
+in that order. For example, if the argument is @code{libx264-max}, it will
+search for the file @file{libx264-max.avpreset}.
+
@section Video and Audio grabbing
If you specify the input format and device then ffmpeg can grab video
ffmpeg -f oss -i /dev/dsp -f video4linux2 -i /dev/video0 /tmp/out.mpg
@end example
+Or with an ALSA audio source (mono input, card id 1) instead of OSS:
+@example
+ffmpeg -f alsa -ac 1 -i hw:1 -f video4linux2 -i /dev/video0 /tmp/out.mpg
+@end example
+
Note that you must activate the right video source and channel before
launching ffmpeg with any TV viewer such as
@uref{http://linux.bytesex.org/xawtv/, xawtv} by Gerd Knorr. You also
mapping from input stream to output streams:
@example
-ffmpeg -i /tmp/a.wav -map 0:a -b 64k /tmp/a.mp2 -map 0:a -b 128k /tmp/b.mp2
+ffmpeg -i /tmp/a.wav -map 0:a -b:a 64k /tmp/a.mp2 -map 0:a -b:a 128k /tmp/b.mp2
@end example
Converts a.wav to a.mp2 at 64 kbits and to b.mp2 at 128 kbits. '-map
projects / ffmpeg / blobdiff