Subject: Re: [linux-audio-dev] cpu/disk tradeoff
From: David Olofson (audiality_AT_swipnet.se)
Date: to loka 14 1999 - 21:05:59 EDT
On Fri, 15 Oct 1999, Bill Gribble wrote:
> Why not use 32-bit int for your intermediate results? a 4-byte float
> wastes a lot of its representational ability on numbers way, way
> beyond the bounds of what you need to be able to operate on for audio.
1) Normalizing is expensive and needs a "level stamp"
for every buffer. Great fun when adapting buffer
sizes accross sub nets and clients... *not*
2) Why convert back and forth all the time?
> If you're interested in serving even the semi-pro audio world, you
> want to be able to handle 24-bit input and output. Commodity machines
> (ADAT/DA-38, plus any external A/D/A worth the bubble wrap it's
> packaged in) are at least 20-bit these days, and most folks want
> 24-bit ability even though they're mainly getting random bits down
> there (not to mention that a commercial recording with more than
> 4 bits of dynamic range is an anomaly).
Well, analog noise sounds better than digital quantization
distortion to most people... And, good audio cards *do* have better
than 96 dB SNR and dynamic range, and that's very helpful when
recording. You don't have to adjust the recording level all the time
to stay within -3 dB.
So, yes, >16 bits makes sense. And, it's also the new over-hyped
upcoming standard, so you just gotta' do it anyway...
//David
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