Noise source processing

Enzo Michelangeli em at who.net
Thu Aug 6 08:33:55 PDT 1998


-----Original Message-----
From: mgraffam at mhv.net <mgraffam at mhv.net>
Date: Thursday, August 06, 1998 10:17 AM


[[...]>The noise coming off of the sound card is more beige than white
though..
>
>Does anyone know of any papers, articles or whatever on good techniques to
>remove bias from the audio source?
>
>My initial thoughts are along the lines of just hashing everything, but
>this will be slow, and I'd like to see what other ideas are out there.

What about an analog filter placed before the digitizer? Nowadays there
should be inexpensive single-chip implementations of multiple-tap equalizers
made for consumer audio. You just have to straighten up the amplitude
ignoring the phase rotation, because the power spectrum is a real-codomain
function (being the Fourier Transform of the autocorrelation, which is an
even function). It won't be perfect, but it'll help.

Enzo










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