[Asterisk-Dev] Re: MS-ADPCM in format_wav?

[Tony Mountifield]

In article <1107359089.2799.18.camel at critch>,
Steven Critchfield <critch at basesys.com> wrote:
> On Wed, 2005-02-02 at 11:02 +0000, Tony Mountifield wrote:
> > Does anyone know if there has been any work done on enhancing format_wav
> > to support MS-ADPCM format (fmt codec type 2)?
> > 
> > If not, I may consider having a go myself, but I don't want to re-invent
> > the wheel unnecessarily.
> 
> You wouldn't modify format_wav under the current method. You can copy it
> to format_wav2 to mimic the way GSM wav files are handled by
> format_wav49. Then you only need to modify the seek function, and the
> header creation/update. After that, you just need to make sure the codec
> is set to adpcm so your incoming frames are already in the right format.

OK, thanks, I'll have a look at that. At the moment, I'm more interested
in being able to play adpcm files than record them. Rather than relying
on a matching codec, I was thinking more of having format_wav2 decode the
ADPCM into SLIN or something, like format_mp3 does.

And having each format in a separate module looks like it requires each
format to have a different file extension, rather than looking at the
fmt chunk in the file to determine the format. Is that correct?

I'll take a look at format_adpcm too. Thanks to you and bkw for the pointers.

Cheers
Tony
-- 
Tony Mountifield
Work: tony at softins.co.uk - http://www.softins.co.uk
Play: tony at mountifield.org - http://tony.mountifield.org