Re: The ALSA Situation

[Manuel Jander <manuel.jander@usm.cl>]

Hi,

On Fri, 2004-11-12 at 09:24 +0100, Andreas Mohr wrote:
> Hi,
> > 2) * Multichannel card:
> >   - Use one channel for softmixing (reserved for ever for that purpose,
> > at highest audio quality). Just the same as for the single channel card.
> >   - Use a "Resource Manager" that assigns hardware channels as are
> > available, and choose the softmixing engine coupled to the reserved
> > channel when we get out of hardware channels.
> 
> Don't we have a problem here??
> 
> If we have 4 hardware-mixed channels and 7 sound streams, then we end
> up with:
> a) H/W (1/4)
> b) H/W (1/4)
> c) H/W (1/4)
> d) H/W (1/4): S/W (1/4), S/W (1/4), S/W (1/4), S/W (1/4)
> == (!!)
> d) H/W (1/4) * S/W (1/4) each == S/W (1/16) each !!
> 
> which clearly has a different volume (1/16 of total output) than each
> of the H/W-mix-only channels (1/4).
> 
> Hmm, OTOH there's a 150% likelihood that the card can adjust hardware
> channel volume individually, so just adjust channel d) to have 4 times
> the volume of each other H/W channel and you end up with equal volume.
> 
> OK, so that should be a non-issue after all (but we need to remember to
> adjust H/W channel volume each time the number of S/W channels changes!),

OK, there maybe some details, but that it absolutely irrelevant, because
it *can* be solved. The really import thing here IMHO is to solve the
concurrent access to the soundcard in a most useful manner, which is an
issue that is *not* solved yet.

-- 
Manuel Jander
Electronic Engineer



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