Ed Kelly wrote:
It is really just the pixel-resolution of the graph. The graph size is 252, but the FFT size is 4096 ( giving 2049 points within the Nyquist frequency ).
Hmmm....I think I follow...but if that reason holds, if I expand the graph to 256 and use a block size of 512, it should be pixel perfect eh? I tried that earlier today, but saw the same behavior...
So you will see magnitude peaks between the pixels as lower amplitude because the screen doesn't display pixels between pixels. I hope this makes sense,
That *does* make sense. It's for display reasons that I ultimately want to build a little scaling control into the abstraction...but I gotta get the basics going first.
Any other ideas?
I'm a bit new to FFT in the pd context, but I think I grok Nyquist -- Sampling at S can, at best, yield the S/2 frequency (where S is the sampling rate). But how does this relate to block size in the DFT? Your original statement sounds like the max frequency out of the fft is (block size)/2...but that can't be right, eh?
Thanks,
-jason