On Feb 7, 2011, at 8:35 PM, Spencer Russell wrote:
On Sun, Feb 6, 2011 at 11:15 PM, Mathieu Bouchard
matju@artengine.ca wrote:On Sun, 6 Feb 2011, Spencer Russell wrote:
[1] gives the magnitude frequency response given the biquad coefficents, and it linked to from several places around the net. Is this the sort of thing you're looking for? [1] http://bit.ly/eFck4j
This link got me directly to :
USB complete: everything you need to develop custom USB peripherals Par Jan Axelson Chapitre 12 Page 364
and nothing else. (??)
Whoops, I meant to send this: http://bit.ly/gUCBu4. Sorry.
Here he's basically just taken the transfer function of a biquad and made the z = exp(j*w/Fs) as Mike suggested, followed by taking the magnitude and log-scaling for dB, but he's done the algebraic legwork. Just note that w (lower-case omega) is 2*pi*f and you should be good to go. He's also done some trig-substitution for more numerical precision.
I'm making good progress, but now am getting lost in the filter math
meeting the pixel math. Can someone mathy check my math? Or even try
it out?
https://github.com/pd-projects/filterview
.hc
¡El pueblo unido jamás será vencido!