Re: Logarithmic Interpolation

Michel Rouzic wrote:

I didn't wanna talk about this too much, because I rather
realize by myself if it's a dumb idea than be told, but my plan
is to *try* using that to perform pitch shift/time stretch.

my basic idea is, get the FFT of the signal you want to shift,
interpolate the FFT logarithmically, shift the contents towards
the left or the right depending on what you want to obtain,
interpolate back to linear form, IFFT. of course, i'm definitly
not sure and quite sceptical about the odds of obtaining the
wanted result, but I think it's worth trying.

Since adding to log frequency is the same as multiplying linear
frequency you can get the same thing with just one interpolator,
used to resample the scaled spectrum.


Martin

--
A trick that is used more than once is called a method.
--Ron Getoor paraphrasing George Polya and Gabor Szego
.

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