scott <sco### [at] scottcom> wrote:
> >  (Btw, did you know that even if a sound signal has only one single
> > frequency, a discrete fourier transform is usually completely unable
> > to find that single frequency, and instead will find a large (potentially
> > infinite) amount of frequencies around that real frequency?)

> It just depends how many samples you use for your fourier transform, the 
> more samples you take, the more accurately you can divide up the frequency 
> spectrum.  If you have a couple of seconds of normal audio recording (so 
> like 100k samples), you should be able to find a single frequency pretty 
> accurately, certainly to within 1 Hz.

  If the actual frequency falls in between two frequencies of the DFT,
there's no way for the DFT to produce just one or a few lines. Only if
the frequency happens to be exactly on one of the frequencies sampled
by the DFT, it will generate one single line.

-- 
                                                          - Warp

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