Subject: Re: Ideas on the audio framework
To: None <tech-kern@netbsd.org>
From: TAMURA Kent <kent@NetBSD.org>
List: tech-kern
Date: 12/05/2004 02:57:11
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* Hardware mixing and software mixing
The first step is to implement software mixing without hardware
support.  Using hardware support is the next step or "nice to
have."  I guess it is hard work to identify a common
representation of mulit-voice hardwares and change the existing
drivers.  The hardware-mixing era already ended, and there is
little possibility that new hardware-mixing audio
controller is introduced.

* API for userland
I think we don't need to change the audio API for userland and
shouldn't change it.


> Sure, but I'm asking what happens on hardware that supports one
> variable-rate voice when I play one stream at 44100 and then a second
> at 24000. Do we then up-sample both to 48000?

We should use the minimum rate which is equal to or higher than
rates of any input streams because sampling rate conversion to
higher rate needs higher CPU cost.

-- 
TAMURA Kent <kent_2004 at hauN.org> <kent at NetBSD.org>


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