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author | Anton Khirnov <anton@khirnov.net> | 2011-11-05 16:23:23 +0100 |
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committer | Anton Khirnov <anton@khirnov.net> | 2011-11-06 18:38:53 +0100 |
commit | d9b49e72a652106d2b99a5cbbfe76da0bd749aed (patch) | |
tree | 725a166c5fc95e7a142811a60d00fda90e1f56f6 | |
parent | 2b56db5869ddc9d5926fd4575e11bf3649dbd9ff (diff) | |
download | ffmpeg-d9b49e72a652106d2b99a5cbbfe76da0bd749aed.tar.gz |
doc/avconv: elaborate on basic functionality.
-rw-r--r-- | doc/avconv.texi | 21 |
1 files changed, 21 insertions, 0 deletions
diff --git a/doc/avconv.texi b/doc/avconv.texi index 41e2771979..139229694e 100644 --- a/doc/avconv.texi +++ b/doc/avconv.texi @@ -26,6 +26,23 @@ avconv 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. +avconv 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: |