Cepstral Waterfall

This exercise introduces the concept of creating “Waterfall Plots” of frame-by-frame cepstrums.

This MATLAB exercise introduces the concept of creating so-called “Waterfall Plots” of frame-by-frame cepstrums/log magnitude spectrums of a time-varying signal such as a speech waveform. Such plots enable tracking ofchanges in the cepstrum, especially during voiced regions, where we detect the changes in pitch period from a frameby-frame analysis of the speech signal. This program can also be used to provide a type of ’debug mode’ for displaying the signal, its log magnitude spectrum, and the resulting real cepstrum of a frame of speech with a user-selected starting sample and frame duration, on a frame-by-frame basis.