[alsa-devel] Compressed Audio Playback/Capture through ALSA framework

[Mark Brown]

On Wed, Mar 16, 2011 at 01:00:09PM -0500, pl bossart wrote:
> On Wed, Mar 16, 2011 at 12:53 PM, Mark Brown

> > It'd make the tie up with algorithms part much easier as we could have
> > an interface for transferring the compressed data alone and then
> > externally describe how that's plumbed into any other DSP that's going
> > on and the physical outputs - it'd help with treating the data transfer
> > as a standalone problem.

> Still not convinced. Why would you need to 'externally describe' how
> compressed data is linked to post-processing. It's all part of DSP
> firmware, why should anyone care how the decoder provides data to
> post-processes? You can control post-processes with ALSA controls as
> for regular PCM.

The problem is figuring out which controls are where and what can be
joined up with what.  This is a problem with regular PCM too but it gets
much worse when everything is virtual.  Media controller should provide
a route to allowing applications to figure out what's going on in the
hardware.