A function main_peak() in fric_meas.py reports some measures for the acoustic analysis of fricatives - including an approach to Shadle's major peak analysis method, and the more commonly used moments analysis that Forrest et al originally proposed for the analysis of stop bursts.

The use of this function is illustrated in a notebook for the TIMIT corpus. The notebook illustrates how the function is called, and shows some plots of results. This is for illustrative purposes only. I would highly recommend that fricative analysis only be done with audio sampled at at least 22050 samples per second (TIMIT has a sampling rate of 16000).

Keith Johnson