cepstrum definition mathematics
(Coined in a 1963 paper by Bogert, Healey, and Tukey) The Fourier transform
of the log-magnitude spectrum:
fFt(ln( | fFt(window . signal) | ))
This function is used in speech recognition
and possibly elsewhere. Note that the outer transform is NOT an inverse Fourier transform (as reported in many respectable DSP texts).
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