Clrrus Logic Voice Codec for rmdtopvf: does anyone have one?

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Hi,

On Wed, Jul 07, 1999 at 11:20:27AM +0000, gordond42@my-deja.com wrote:
> I have a dynalink V1414VH (or something like that) voice/fax/data modem (a
> CL-MD1414AT/EC according to my vgetty logs).It works fairly well with vgetty.
>  But it uses it's own codec for the voice and rmdtopvf does not support
> it.rmdfile produces the following
> output:/var/spool/voice/messages/standard.rmd: RMD1modem type is: "Cirrus
> Logic"compression method: 0x0001sample speed: 9600bits per sample: 5I have
> tried all the codecs that rmdtopvf supports (by hacking the source); none of
> them produce output near what the modem does (it's very noisy; seemingly pure
> luck that I get anything remotely recognisable at all).I am guessing it uses
> some sort of ADPCM compression (in mode 1) but I don't know how to go about
> decompressing it.  The IMA ADPCM driver (multitech.c) in libpvf seems to only
> work with 4 bit samples; otherwise it might have worked.Does anyone else have
> any idea how I might be able to decode my .rmd files?ThanksDonald Gordon

Sounds like you need to find out what the exact encoding algorithm of
that modem is (ask the modem vendor for specs) and then someone will
have to adapt the pvftormd/rmdtopvf tools...

Not much we can do for you here...

gert

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