Cepstrum computation

["Argiris A. Kranidiotis" <akra@xxxxxxxxx>]

Dear all,

I have a really simple question about the computation of the Cepstrum.

The definition of the Cepstrum C(t) is:

                          C(t)=|| FFT( log( ||FFT(x)|| ) ) ||

My question is: what happens when ||FFT(x)||=0 for some x?
Then we have to compute log(0), which is undefined (as we all know).

I suspect that I am missing something here, but this problem isn't
mentioned
anywhere in my books.

(BTW: Does anyone know any kind of improvement of the original Cepstrum
method in order have better pitch estimates?)

Thanks in advance,

Argiris A. Kranidiotis

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    /  Argiris A. Kranidiotis  _/ /\  /       University Of Athens     _/ /\
   / Doctoral student (Ph.D.) / \/   /     Informatics Department     / \/
  /   in Computer Science     /\    /   http://www.di.uoa.gr/~akra    /\
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