🚀 go-pugleaf

In article <3441@abaa.UUCP> esker@abaa.UUCP (Lawrence Esker) writes:
[...]
>Yes, the sliding-FFT looked like a great design invention until you studied
>it more closely and realized it was simply the original Discrete Fourier
>Transform (DFT) restated in a different way.  Since the FFT is an algorithmic
>shortcut to the DFT, it made me chuckle to see the DFT used to perform the
>FFT, albeit under a new name of sliding-FFT.

You never stated whether you thought the DFT could be done in real time.
The "sliding-FFT" (whatever you wish to call it) seemed simple enough (in
terms of how many math computations per sample) for converting real-time
audio into the frequency domain.  But it does appear that computing an
additional inverse FT under the same time constraints would not be
possible.

Its been a while since I studied this in college, anyone care to describe
the DFT vs. FFT in layman's terms, or point to a text which does?  I seem
to remember that the inverse FT is basically the same operation as the FT
from time- to frequency-domain...

One use for real-time FT would be a digital spectrum analyser with say
256 points instead of the usual 10 band versions available with analog
units.  Gotta have some blinky light algorithms for my DSP project board
to execute :-)

Brian Willoughby
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