changing the pitch of an audio wav file in matlab?

Question

How do you go about changing the pitch of an audio signal in matlab?. Essentially I just want to change the original qualities of the audio signal without making a dramatic change. I'm trying to use the original input audio to simulate a chorus by changing its qualities slightly so that I can have multiple variations of the audio to simulate the chorus.

Answer 1

This simplest approach might be a phase vocoder. You can find one matlab implementation here:

http://labrosa.ee.columbia.edu/matlab/pvoc/

This is a rabbit hole, though. There are so many more techniques that can employed to improve the quality and reduce the artifacts introduced by pitch shifting. See for example, Jean Laroche and Mark Dolson, "New Phase-Vocoder Techniques for pitch shifting, harmonizing and other exotic effects", proc. 1999 IEEE Workship on Applications of Signal Processing to Audio and Acoustics, p. 91.