[sdiy] dsPIC pitch shifter

[Richie Burnett]

Been playing about with pitch-shifting using a dsPIC33FJ128GP802.  (Think 
monophonic pitch-shifter like the early Eventide Harmonizers.)  Have posted 
some results here:

http://www.richieburnett.co.uk/temp/pitch/

Uses autocorrelation to continuously search for the best splice points in 
real time.  Formant positions aren't preserved so speech eventually tends 
towards chipmunk or Satan if you shift too far in either direction.

-Richie,