[linux-audio-dev] Pitchshift/Timestretch project..

[Florian Schmidt]

On Tue, 6 Apr 2004 07:33:50 +1000
Erik de Castro Lopo <erikd-lad at mega-nerd.com> wrote:

> On Tue, 06 Apr 2004 00:59:39 +0200
> Marek Peteraj <marpet at naex.sk> wrote:
> 
> > Hi Erik,
> > 
> > On Mon, 2004-04-05 at 22:25, Erik de Castro Lopo wrote:
> > > 
> > > There are other people working on something like this.
> > 
> > Could you reveal some details? :)
> 
> Well me. I've been working on this since the start of the year, but
> been thinking about the problem for over 10 years. 

I've only been thinking about how this is done for very short periods of
time. My naive approach to timestretching would be to transform the
signal into the frequency domain [either by windowe fourier or by
wavelet transform]. and then afterwards retransform, but with a changed
time base. Actually i rather think of it as synthesizing the
timestretched material from the frequency information..

I'm sure i miss something [haven't actually looked at the math
[especially for the retransform with changed timebase] though i do have
some fourier/wavelet transform knowledge]

Florian Schmidt

-- 
kT