[ANNOUNCE] New Mixer Handling in PA 0.9.16/F12

[Lennart Poettering]

On Wed, 29.07.09 12:33, Michal Hlavinka (mhlavink at redhat.com) wrote:

> 
> > This reminds me your note:
> >
> >    
> > https://tango.0pointer.de/pipermail/pulseaudio-discuss/2009-July/004519.htm
> >l
> >
> >     PA does not make use of hardware mixing. And I don't plan to change
> >     that. It's obsolete technology. CPUs these days come with extensions
> >     such as MMX or SSE precisely for speeding up DSP tasks such as PCM
> >     mixing. This is way more flexible that hw mixing, and definitely the
> >     way to the future, both on the desktop and on embedded envs as well.
> >
> >
> > The "obsolete technology" -- who made this decision? Is it your private
> > opinion or any suggestion from sound card manufacturers?
> >
> > It seems that HW companies still produce the "obsolete technology".
> 
> First, I like pulseaudio, especially the ability of moving streams from one 
> sink to another is awesome for laptops with external sound card :o)
> 
> But imo hw mixer (or other hw parts) are not that bad... we still have hw 
> accelerated graphic, math,... why not sound? Also this remains me that 
> pulseaudio eats 24 % of my (1.6GHz) cpu when mapping stereo stream to 5.1 
> which (I suppose) some hw mixer could do while letting cpu free for other 
> tasks.

If PA eats a lot of CPU this can have many reasons, most of them have
to do with the latency settings requested by the applications  or that
have been configured due to frequent underruns. However the actual
mixing is certainly the smallest part of it. Plese don't forget that
mixing is not exactly the most complex operation on earth.

But then again, I am happy to take patches.

Lennart

-- 
Lennart Poettering                        Red Hat, Inc.
lennart [at] poettering [dot] net
http://0pointer.net/lennart/           GnuPG 0x1A015CC4