Re: Audio to pitch is not a solved problem. Don't expect it to work for general cases anytime soon!

From: phil osborn (
Date: Sun May 28 2000 - 00:19:27 MDT

>From: James Rogers <>
>Subject: Re: Audio to pitch is not a solved problem. Don't expect it to
>work for general cases anytime soon!
>Date: Fri, 26 May 2000 07:38:49 -0700
>On Thu, 25 May 2000, Eirikur Hallgrimsson wrote:
> >
> > Assuming that you can build hardware that somehow does discriminate
> > pitch as fast as we do, you have the latency issue that you are now
> > ready to start playing the note that the human audience has already
> > heard from the source (whistle, guitar-string or whatever) and you
> > start late. You just can't make this work in real time performance
> > situations, even if you can hide the original control signal from the
> > audience. The control signal matched the timing of the other
> > performers, but the resulting tone is unavoidably late. Playing solo
> > doesn't solve it either because what you are hearing is the note that
> > you were humming, played as trumpets, not the one that you are trying
> > to hum right now. The actual note-rate (tempo) that can be
> > accomplished is really slow.
>Audio-to-pitch *is* effectively a solved problem.
>Latency is not an issue and the amount of DSP required to do this well
>is dirt cheap. For example, there exist cheap boxes that will do
>real-time pitch correction, a function which requires both detailed pitch
>discrimination *and* artifact-free signal re-synthesis. One popular one,
>the Antares Autotune, has a latency of <4ms, which is effectively
>instantaneous in audio terms (esp for live use). In practice, solid
>implementations of these pitch discrimination/resynthesis algorithms are
>transparent and highly effective.
>-James Rogers

At the first CyberArts conference in L.A. in 1990 - the BEST digital arts
conference ever held! - a man who created the systems used by the big record
houses to clean up recordings demonstrated a live system into which he read
a poem. He then stated that this system could take his input and output it
as ANY sound, retaining legibiilty. Then he demonstrated it, having the
system speak back his vocalization, using the sound of waves crashing on a
beach. It was waves crashing on a beach, reading poetry, retaining perfect
legibility and retaining his style. Clearly, such a system could take my
rather lousy singing voice and map it to Caruso. So, where can I buy it?

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