Subject: Re: Pitch Shifting Algorithm From: Pierre Divenyi <pdivenyi@xxxxxxxx> Date: Sun, 25 Jun 2006 21:07:50 -0700--=====================_131565343==.ALT Content-Type: text/plain; charset="us-ascii"; format=flowed Ben, "Pitch" refers to fundamental frequency, most of the time. I think what you want is a spectral up-shift which is actually easier than the former. There are spectral transposition algorithms that will displace the spectrum downward -- a simple Fourier transform with frequency shift will work. Some algorithms of this sort are put in special hearing aids for persons who have lost their hearing in the 2-4-kHz region indispensable for speech intelligibility. There is no reason the same algorithms could not be used to shift the spectrum upwards. Pierre At 05:33 PM 6/25/2006, you wrote: >Hi All, >I've had a request from someone in our department for suggestions >for a pitch shifting algorithm that will be used to shift the >frequencies of phoneme pairs (e.g. ba-da) into the center range of >rat hearing (~8kHz) without affecting the temporal cues of the >speech stimuli. I'm unfamiliar with available software to do this >(and pros and cons for specific kinds). We do have some commercial >software here such as Adobe Audition and SoundForge that have pitch >shifting algorithms as part of their software package. We are hoping >to limit artifact as much as possible. Would these be appropriate >algorithms to use? If not, why not and any suggestions as to which >software program would be more appropriate? > >Thanks, > >Ben Hornsby --=====================_131565343==.ALT Content-Type: text/html; charset="us-ascii" <html> <body> Ben,<br><br> "Pitch" refers to fundamental frequency, most of the time. I think what you want is a spectral up-shift which is actually easier than the former. There are spectral transposition algorithms that will displace the spectrum downward -- a simple Fourier transform with frequency shift will work. Some algorithms of this sort are put in special hearing aids for persons who have lost their hearing in the 2-4-kHz region indispensable for speech intelligibility. There is no reason the same algorithms could not be used to shift the spectrum upwards.<br><br> Pierre<br><br> At 05:33 PM 6/25/2006, you wrote:<br> <blockquote type=cite class=cite cite=""><font size=2>Hi All,<br> I've had a request from someone in our department for suggestions for a pitch shifting algorithm that will be used to shift the frequencies of phoneme pairs (e.g. ba-da) into the center range of rat hearing (~8kHz) without affecting the temporal cues of the speech stimuli. I'm unfamiliar with available software to do this (and pros and cons for specific kinds). We do have some commercial software here such as Adobe Audition and SoundForge that have pitch shifting algorithms as part of their software package. We are hoping to limit artifact as much as possible. Would these be appropriate algorithms to use? If not, why not and any suggestions as to which software program would be more appropriate?<br> </font> <br> <font size=2>Thanks,<br> </font> <br> <font size=2>Ben Hornsby</font></blockquote></body> </html> --=====================_131565343==.ALT--