ipad - iPhone voice changer

Question

I am developing an iphone app, which records user voice and change it into a female voice like (TALKING TOM and iHOBO). I am new to audio manipulation. Please tell me which api is required to do this? Can i implement this feature using iphone sdk apis? Is there any open source to implement this feature? Is there any tutorial regrading this?

Thanks in Advace

Answer 1

There are no built-in iOS APIs that will do independent time-pitch modification.

There is open source code that implements time-pitch stretching in Audacity, but I don't know whether this code has been ported to iOS. Same with SoundTouch.

There is a Time-Pitch Stretch Tutorial on the DSP Dimensions site.

Update: In late 2012, the kAudioUnitSubType_NewTimePitch Audio Unit was included with and built into the release of iOS 6, so you can now implement (independant time-pitch modification) voice changing using iOS APIs. See Apple's developer documentation for details.