On Mon, May 28, 2012 at 01:30:37PM -0400, David Robillard wrote:
> > Take a filter plugin. Calculating the actual filter coefficients
Assuming that by 'signals' you mean audio rate controls, yes.
Again, the exception is 'synthesis' modules. You'd expect a
VCA in a modular synth to do what the ADSR tells it to do,
even if that results in artefacts. But you wouldn't want a
fader in a DAW (essentially the same thing if implemented as
a plugin) to do the same.
> It's better in many cases to be explicitly told when the control value
Yes, but if that 'when' is not a regular period, and assuming you
want to actually reach the value, there's little you can do excecpt
linearly interpolate from the previous value. This makes the control
value continuous, but not its derivative(s). And that can be more
than enought to generate clicks, zipper noise, etc. Not only you
don't know what the next value will be, you don't even know when
it will arrive. It could be one millisecond later or one minute.
So the only thing you can do to have click and zipper-free output
is to apply enough filtering to guarantee this, whatever the input.
Which means ignoring most of the 'detail' in the input. Which in
turn means it's futile to provide such input in the first place.
A world of exhaustive, reliable metadata would be an utopia.
It's also a pipe-dream, founded on self-delusion, nerd hubris
and hysterically inflated market opportunities. (Cory Doctorow)
Linux-audio-dev mailing list