I have a recording of speech, and I want to manipulate the voice, so a listener will perceive the manipulated voice and the original one as belonging to two different people. The manipulated voice should sound very natural, not computer-generated.
Just to clarify, the manipulated voice does not have to be modeled after the voice of someone; I'm not asking about mimicking a voice, as discussed here.
I have already used the SoundTouch library for pitch shifting, and it produces very nice results, but I want to change not only the pitch.
I saw this impressive video of a software called Voice Sculptor (couldn't find the company site), which demonstrate such a manipulation.
- So I'm asking on a conceptual/algorithmic level how this can be done
- And also if you know how to achieve this with specific tools.
Last note: I'm new to DSP, so I will appreciate any explanation of why and how.