[FFmpeg-devel] Irregular codec

Reimar Döffinger Reimar.Doeffinger
Sat Jun 28 12:05:19 CEST 2008

> I've been writing a demuxer and a decoder for the SMV format (SigmaTel 
> Motion Video) for ffmpeg. It begins with a WAV file, then the SMV header 
> afterwards, then an array of jpegs. I was trying to get my demuxer to be 
> able to read the SMV header, but since it's practically in the middle of 
> the file, the buffer is not that big! So I can't read the header through 
> the buffer. How can I somehow read in the middle of the file with the 
> demuxer_probe(AVProbeData *p) function to be able to read the header 
> (especially with demuxer_read_header())?

IMO just check for wav and return the value for the wav demuxer - 4,
this will then choose your demuxer if the extension matches - if it
doesn't, the user will have to specify the format explicitly.
You could also try checking the file size against the size in the wav
header, but that is not very reliable...

Reimar D?ffinger

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