Re: Playing lots of tiny sounds with different formats?
Re: Playing lots of tiny sounds with different formats?
- Subject: Re: Playing lots of tiny sounds with different formats?
- From: "Timothy J. Wood" <email@hidden>
- Date: Mon, 2 Sep 2002 16:49:07 -0700
On Monday, September 2, 2002, at 01:08 PM, Chris Rogers wrote:
Both the 3D mixer and stereo mixer are unable to do sample rate
conversion
(it's not their job). What you're probably hearing when you feed
sources
with different sample rates to the stereo mixer is that they play back
at the wrong speed/pitch since they're playing back at the wrong
sample rate...
Hmmm... something strange is going on then. I've previously been
able to feed both 44.1kHz and 22kHz sources into a stereo mixer and get
correct sounding results. I guess I should test to make sure that I'm
really confident in this result :)
At any rate, I'm sort of wondering whether I agree with the assertion
that the mixer shouldn't support at least simple sample rate
conversion. I understand that there might be a combinatorial explosion
of mixing inputs that would make this impossible, but I wonder how much
cycles are spent on cache misses when mixing from 44.1kHz floats when
we could be mixing from 22kHz shorts (in the common case for games).
Have you guys done any benchmarks on the number of cycles spent
stalling on cache misses when mixing (with CHUD, say)? Maybe I'm just
paranoid and this isn't a problem -- but having 1/4 the memory
bandwidth usage seems like it might help :)
Thanks!
-tim
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