denormal floats (was Re: [linux-audio-dev] XAP spec - early scribbles)

[Tim Hockin]

> On Thursday 06 February 2003 16.28, Steve Harris wrote:
> [...]
> > #define FLUSH_TO_ZERO(fv) (((*(unsigned
> > int*)&(fv))&0x7f800000)==0)?0.0f:(fv) I think it came from the
> > music-dsp list.
> 
> There's a conditional in there, though.
> 
> Another method is to add noise or some other signal (beep at Nyqvist) 
> with an amplitude a few hundred dB or more below the 0 dB level of 
> audio data.

Which is fine, unless you have a LP filter in your chain.

Maybe a -200dB sine at 1Hz and Nyquist?  But then a BP filter screws you.
Someone once suggested a slight DC offset, though I can't see how that would
solve things like a reverb, unless they preserve it and shift their 0.