Python Data Analysis Cookbook

Analyzing the frequency spectrum of audio

We can apply many techniques to analyze audio, and, therefore, we can debate at length about which techniques are most appropriate. The most obvious method is purportedly the FFT. As a variation, we can use the short-time Fourier transform (STFT). The STFT splits the signal in the time domain into equal parts, and it then applies the FFT to each segment. Another algorithm we will use is the cepstrum, which was originally used to analyze earthquakes but was later successfully applied to speech analysis. The power cepstrum is given by the following equation:

The algorithm is as follows:

1. Calculate the Fourier ...