RealCepstrum Routine

Summary

Compute real cepstrum.

Declaration

Procedure RealCepstrum(Src, Dst: TVec; DumpDC: boolean = True; WindowType: TSignalWindowType = wtHanning; Magnitude: boolean = false);

Description

Compute real cepstrum of Src and place the result in Dst. If DCDump is True, the DC component will be removed prior to computing FFT. WindowType specifies the window type used for the forward FFT. Real cepstrum can be used to find periodicites in the frequency spectrum itself. It is namely defined as an inverse FFT of the logarithm of the magnitude spectrum [1] (p. 770, eq 12.8):


         rc = IFFT(log(abs(FFT(x)))

         x.. time series

Sometimes we also find the following definition:


         rc = FFT(log(abs(FFT(x)))

A good choice for the window function is the Hanning window.

See Also
[1] "Discrete-time signal processing, Oppenheim and Schafer, Prentice-Hall, 1989".
CplxCepstrum
CplxCepstrumInv