Newsgroups: comp.speech
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From: ij285@lu.erisoft.se (Ingemar Johansson)
Subject: Re: Pitch changing?
Message-ID: <1994Sep6.130133.13073@lu.erisoft.se>
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Reply-To: ij285@lu.erisoft.se
Organization: Erisoft AB, Sweden
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Date: Tue, 6 Sep 1994 13:01:33 GMT
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I believe that if you make an FFT on a block of the input signal and then shift the 
FFT components up or down and transform the shifted FFT komponents back to the time
domain with an IFFT you'll get a frequency shifted signal with normal playback speed.

There is also a possibility that you can use a mixer in the same manner as in a radio
receiver. 

There excists a pitch control-IC called MSM6322 that takes care of this business 
in real time. I'm afraid that I don't know the manufacturer but I hope this will help 
you a bit along the way.

//Ingemar Johansson


