Subject: Re: [linux-audio-dev] Plugin APIs (again)
From: David Olofson (david_AT_olofson.net)
Date: Mon Dec 09 2002 - 15:31:24 EET
On Monday 09 December 2002 13.34, Steve Harris wrote:
[...]
> > That, and/or there should be ramp events. Those can be a bit
> > hairy to deal with at times, but please, do suggest an
> > alternative if there is one that is simpler and still sufficient
> > for sample accurate control... (No, no audio rate "raw" control
> > ports, please!)
>
> Heh, maybe not for this API, but they are fundmanetally superior :)
Well, ok. You can have those *too*. (I'm Santa! :-)
Just have a Bay with audio input (or output) channels for each audio
rate control. Then you can connect audio signals to controls and vice
versa.
Then implement an audio->control transformer, and a control->audio
transformer and have the best of two worlds. :-)
> I look forward to a few years where all DSP code can run blockless
> and with audio rate (or near audio rate) control.
Have you considered that timestamped events may actually have
*better* than sample accurate timing...? ;-) (Well, I actually
suspect that subsample accurate timing will show up sooner or later -
as a buzword or because it actually matters. Maybe we should allocate
some bits for it while we're at it?)
And more seriously, how efficient is audio rate controls when you
have tens of them for every channel...? Should you keep recalculating
all of you filer coefficients, reprogramming all of your LFOs and
envelope generators for *every sample* all the time? Or first test
for change in every control for every sample?
I don't think that DSPs or generic CPUs will *ever* be fast enough
that you can completely stop worrying about performance. You think
convolution is heavy stuff? Wait until you see what the cutting edge
high end effects look like in ten years... Trust me, only big studios
will have enough power to run them in real time - just like it is now.
I'm quite sure timestamped events are here to stay - for a very long
time. We'll never have infinite numbers of clock cycles to waste.
//David Olofson - Programmer, Composer, Open Source Advocate
.- The Return of Audiality! --------------------------------.
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`---------------------------> http://olofson.net/audiality -'
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