[openbeos] Re: Resampling algorithms for audio mixer

> >>> Rather than put workarounds for the denormal problem in
> >>> the resampling algorithm (thus slowing it down), I propose
> >>> completely disabling denormals on the CPU across the entire
> >>> OS as standard.
> >> This is up to Haiku devs :-)
> >
> > At least I have no clue about this, but we don't have to decide
> > this today, don't we? :-)
> > Do we even have a choice with being BeOS compatible and all
> > (as I said, I have no idea what I'm talking about, just in case
> > you're wondering)?
> 
> Denormals are very small floating numbers.
> Calculation under this "subnormal" level often switch FPU into a 
> slower cycle
> state, which could hit badly the whole system, especially on P4's.
> While in scientific computing field it's obviously well tolerated, 
> when it comes
> to near zero floating point audio samples, hit doesn't worth it and a 
> plain
> silence is better than an near zero silent but slower system.
> 
> CPUs can be set to consider denormals as zero, per SSE+ FTZ & DAZ 
> flags
> 

Hmm what about fixed point ?
Could be vectorized with mmx..

François.

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