[linux-audio-dev] jack_process and pitch-shifting

[Erik de Castro Lopo]

On Fri, 22 Apr 2005 17:13:47 +0200
Olivier Guilyardi <ml at xung.org> wrote:

> Hi,
> 
> In Jackbeat, I want to include support for realtime pitch shifting. One 
> of the option is to use a quality resampler as libsamplerate's 
> SRC_SINC_BEST_QUALITY converter.

Err, the only think you can do with libsamplerate alone that even comes
close to pitch shifting is the vary speed effect (change the playback
speed and the pitch changes).

Secondly, for any real time operation, SRC_SINC_BEST_QUALITY is complete 
overkill.  I would honestly suggest SRC_SINC_FASTEST.

>  In the future, I may add support for 
> libsoundtouch1 (http://sky.prohosting.com/oparviai/soundtouch/index.html).

Libsoundtouch can do constant pitch time stretching. If you combine
that with libsamplerate's vary speed capabilities then you get 
pitch shifting.

Erik
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  Erik de Castro Lopo  nospam at mega-nerd.com (Yes it's valid)
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