lav2wav(1)
NAME
lav2wav - Extract the audio out of MJPEG container files
to stdout
SYNOPSIS
lav2wav [-s num] [-c num] [-v num] [-I] lavfile1 [lavfile2 ... lavfileN]
DESCRIPTION
lav2wav can be used to extract the audio to stdout. This
output goes to stdout and can be saved as a wav file, or
piped to an other sound processing tool, that is able to
handle wave. This can be mp2enc and toolame for mpeg
layer 2 audio, or for example lame for mpeg layer 3 audio.
The input files may be any combination of AVI (.avi), Mov
tar (.movtar), Quicktime (.qt/.mov) or editlist files so
long as they are all lavtools- readable (e.g. MJPEGencoded AVI/Quicktime/Movtar or DV type 2 AVI).
OPTIONS
lav2wav accepts the following options:
- -s num
- Start extracting at video frame (num)
- -c num
- Extract (num) frames of audio
- -v num
- Verbosity level (0, 1 or 2)
- -I Ignore unsupported bitrates/bits per sample
BUGS
The "WAV" file format (technically: RIFF) is really very
much less than ideal for a tool intended to be used in
pipelines as lav2wav is. The Problem is that the header
includes a field specifying the length of the file. This
can't be filled in except by seeking back to the begining
and over-writing. If the output is unseek-able (e.g. pipe
lav2wav simply writes a large length into the header and
leaves it at that). Most tools like sox(1) or mp2enc(1)
either ignore the length field anyway or only give a warn
ing.
AUTHOR
- This man page was written by Bernhard Praschinger.
If you have questions, remarks, problems or you just want
to contact the developers, the main mailing list for the
MJPEG-tools is: - mjpeg-users@lists.sourceforge.net
- For more info, see our website at
- http://mjpeg.sourceforge.net