Walt,
the SeaWave at present available for free has some limitations, i.e. max
fft = 4096 and others.
As promised earlier, I'll make available to the list members the Pro
version. Let me compile the latest updates and put it on an ftp server. All
those interested can ask me the ftp address and password.
You'll find the ability to run the fft up to 16K in real time. This is
mostly useful to zoom 32X on the frequency axis (the frequency zoom ratio
is given by fftsize/512).
Gianni
At 12.51 16/03/2003 -0500, you wrote:
>Gianni Pavan wrote:
> > In the windows software I developed (see previous message or the page
> > http://www.unipv.it/cibra/softw.html) the time resolution one can get in
> > real-time depends on the sampling rate (up to 192 kHz on standard windows
> > boards), on the number of channels (1 or 2), on the chosen fftsize (512 to
> > 16384), on the step among consecutive transforms (2 samples up to the
> > chosen fftsize) and, of course, on the available processing power. The
> > window length (16 samples to fftsize) and shape (I like gaussian and
> > kaiser-bessel) is not relevant for computation time. The computation
> > efficiency can be slightly modified by setting a proper data transfer
> > blocksize which affects the latency of the display.
>
>Are you here talking about your DOS program or the Windows program?
>Certainly SEA is more limited.
>
> > Very few programs allows to modify all these parameters to get the desired
> > frequency-time resolution in real-time operation.
>
>All too true. Most sonograms have very limited modification so as to
>keep the amount of programming down. And also not to overload as often.
>
>I'm interested in experimenting with FFT sizes in excess of the 4096 I
>have available. I'm a mac user, but have both PC emulation on my mac and
>a PC laptop, so could, with some awkwardness run the programs. I'm not a
>PC expert, so doing elaborate mods to the OS is something I'd not try.
>
>Walt
>
>
>
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