On 08/16/2010 06:21 PM, Pierre Massat wrote:
Hi,
I've been thinking of writing a pd version of autotune, but before i get started i m wondering if anybody as ever tried doing this?
not in pd, but in reaktor and c. combining pitch-detection and a pitchshifter (and some quantization) works quite well, and should be not too hard to do in pd (fiddle and the pitchshifter from the docs). though this is quite good for subtle pitch correction, it does not create the typical, metallic, vocoder-like "cher-effect".
maybe something like taking single-cycle-samples of the input, when a constant pitch is detected, and playing these instead of the original audio would do better, but i have not tried yet. (and i think detecting zero-crossings in pd (vanilla) is rather difficult...)
I m assuming they're making a ton of money selling it, so there 's probably not much information available as to how it actually works, but i guess Miller Puckette's Phase vocoder example could be a good starting point.
i do not think that autotune uses fft-based methods, since it has very little latency (and does not need too much cpu).
bis denn! martin