doc/ffmpeg.texi

Merge changes done to avconv.texi since the last merge into ffmpeg.texi

Signed-off-by: Michael Niedermayer <michaelni@gmx.at>
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Michael Niedermayer 2011-12-11 18:50:39 +01:00
parent c3068d43a8
commit 616eaea8ad
1 changed files with 81 additions and 7 deletions

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@ -26,6 +26,23 @@ ffmpeg is a very fast video and audio converter that can also grab from
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
@ -33,6 +50,10 @@ then applied to the next input or output file.
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:
@ -171,10 +192,6 @@ To set the language of the second stream:
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
@ -203,10 +220,48 @@ Stop writing to the stream after @var{framecount} frames.
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
@ -218,7 +273,7 @@ Set the number of video frames to record. This is an alias for @code{-frames:v}.
@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
@ -593,6 +648,10 @@ frames after each specified time.
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
@ -617,7 +676,7 @@ Disable audio recording.
@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
@ -995,6 +1054,21 @@ quality).
@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