Three Formants Analysis
In order to view the changes of more than 2 formants over time, the formants of all frames can be plotted in a 2-D graph. The results are shown in following figures for two different speakers.
Formants of “five” spoken by a female speaker
The circles on each graph show the location of the voiced region for /ai/ in digit “five”. Even that two speech signals are from different speakers of different gender, a few common properties can be seen from the graphs. Firstly, the voiced regions have respectively high amplitude compare to unvoiced region. The normalized amplitudes are shown with the intensity of the star marker (*). The darker markers indicate higher amplitudes. Secondly, there is a trend for the changes of diphthong in the voiced region, and the formants can be classified into certain ranges.