ADPCM and Wine

[Patrik Stridvall]

> Is anybody working on support for playing ADPCM wave files 
> under Wine? 

Not that I know of.

> If not, I'd like to take a crack at it.

By all means.
 
> I have an app that I use (Delorme's AAA MapNGo 4.0) that uses 
> ADPCM wave 
> files to contain spoken information on attractions. I know 
> that Wine can 
> access my sound system to play normal PCM wave files, as MN4 also has 
> speech synthesis that does work. However, any attempt to play a ADPCM 
> file results in the program pausing for a length of time, then 
> continuing. I infer that this is because the lower levels of 
> Wine don't 
> know how to handle ADPCM.

That most likely correct.
 
> ADPCM isn't rocket science - several programs, including sox, 
> understand 
> the protocol.

OK.
 
> So, is anybody working on this (outside of TG and Lindows)? Any 
> (non-null) pointers to useful information on how Wine has put 
> together 
> the sound subsystem? I'm not a Windows programmer, I'm an embedded 
> systems and DSP person, but if I can find a block of code to 
> hook into I 
> can make this happen.

I suggest you talk to Eric Pouech <eric.pouech at wanadoo.fr>.
He was active on the patch list yesterday so I suppose he
will see this and reply.

In the mean time I can tell you that the PCM support is in 
wine/dlls/mcacm and ADPCM support should be there as well.

There is a file pcmconverter.c that implements PCM support
so I suppose that there should be a adpcmconverter.c file
to plug in the ADPCM support. There will probably need
to be a few changes in other files as well.

Anyway Eric understands this better than I do.
Let's wait and see what he has to say.