[linux-audio-dev] XAP spec & PTAF comments [merge]

[torbenh at gmx.de]

On Sun, Feb 09, 2003 at 12:16:02AM +0000, Steve Harris wrote:
> On Sat, Feb 08, 2003 at 12:03:01 -0800, Tim Hockin wrote:
> > > Branching to fill your delay line with explit 0.0's intead of reading them
> > > from a buffer of zeros doesn't help. We allready know that reverbs cant
> > > support it at all. Efficieny reasons would also rule out flangers, delays,
> > > most filters and choruses.
> > 
> > Maybe I'm missing something, but how can a test that amounts to this NOT be
> > faster than doing any work at all?
> > 
> > if (me->silent && XAP_BUF_SILENT(me->in[0]) && XAP_BUF_SILENT(me->in[1])) {
> > 	return;
> > }
> 
> You still have to roll your internal delay lines, its just that you know
> they will only have zeros going into them.


it should be silent if( zeros_pumped_in > delay_samples*n )

with    n = min{ n | feedback^n < threshold }   ->   n = ceil(log_{feedback} threshold)


-- 
torben Hohn
http://galan.sourceforge.net -- The graphical Audio language