cepstrum

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cepstrum

[′sep·trəm]
(acoustics)
The Fourier transform of the logarithm of a speech power spectrum; used to separate vocal tract information from pitch excitation in voiced speech.

cepstrum

(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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References in periodicals archive ?
Tukey', Proceedings of the Symposium on Time Series Analysis 1963, The Quefrency Alanysis of Time Series for Echoes: Cepstrum, Pseudo Autocovariance, Cross-Cepstrum and Saphe Cracking, pp.