[linux-audio-dev] Olypus voice recorder - codec?

[Dan Stromberg]

On Tue, 2006-01-03 at 17:50 +1100, Erik de Castro Lopo wrote:
> David Santinoli wrote:
> 
> > AFAICT the encoding should be (Adaptive Differential Pulse Code
> > Modulation).  Don't know about the file container though...
> 
> There are at least 50 different, mutually incompatible types
> of ADPCM. For instance, libsndfile supports:
> 
> 	SF_FORMAT_IMA_ADPCM	/* IMA ADPCM. */

The data is coming out of the windows app in this format: IMA ADPCM,
that is.

But unfortunately, I don't seem to be having much luck discovering what
codec they actually spit out of the voice recorder, prior to the
application apparently converting it to IMA ADPCM.

> 	SF_FORMAT_MS_ADPCM	/* Microsoft ADPCM. */
> 	SF_FORMAT_VOX_ADPCM	/* OKI / Dialogix ADPCM */
> 	SF_FORMAT_G721_32	/* 32kbs G721 ADPCM encoding. */
> 	SF_FORMAT_G723_24	/* 24kbs G723 ADPCM encoding. */
> 	SF_FORMAT_G723_40	/* 40kbs G723 ADPCM encoding. */
> 
> which is a mere drop in the bucket.
> 
> Erik