Structure of the peakdet_inter back end

This page provides explanations about the structure of the peakdet_inter back end. (Work in progress towards version 1.1.)

• The main script, peakdet_inter, operates on a WAV file that contains several tokens (typically syllables. For each of these tokens, it calls the function FO.

• In turn, FO calls the following functions:

  • CRO to find positive peaks: crossings with the threshold on the derivative of the electroglottographic signal

    • In turn, CRO calls rim for detection and verification of crossings

  • AMPOS to detect the amplitude and position of all the peaks in the portion of signal

    • In turn, AMPOS calls peakshape. This is a key component of the back-end. Analysis of peak shape is performed inside this function, using the first and second derivatives of the electroglottographic signal. Closing peaks are detected from the second derivative of the signal, then compared on the basis of their characteristics on the first and second derivatives.

• FO then proceeds to calculation of fundamental frequency, followed by detection of openings.