NAME

       lav2wav - Extract the audio out of MJPEG container files to stdout

SYNOPSIS

       lav2wav  [-s  num] [-c num] [-v num] [-I] [-R] [-r samplerate, bitesize, channels] 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 another sound processing tool that is able to handle the wav format.  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), Quicktime (.qt) or editlist files so long  as  they
       are all lavtools- readable (e.g. MJPEG-encoded AVI/Quicktime 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

       -R   If the file does not contain any sound. lav2wav will create silence with 44100kHz Sampelrate, 16 Bit
            audio bitsize and 2 Chanels

       -r sr,bs,ch
            If  the file does not contain any sound lav2wav will generate silence with the values you supply the
            samplerate (sr), audio-bitsize (bs) and channel (ch).

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  unseekable  (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 warning.
       The audio length is inacurate calculated when lav2wav generates silence.  This happens only if  you  have
       NTSC framerate and than it creates for every hour of video 1.1498sec too less of silence.

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

SEE ALSO

       mjpegtools(1), mp2enc(1), sox(1)

MJPEG Tools Team                                   2 June 2001                                        lav2wav(1)