Methods for formant extraction in speech of patients after total laryngectomy

The paper shows the methods and its application for voice analysis suited to the group of subjects after total laryngectomy surgery. Our software was developed to evaluate and enhance laryngectomized patients’ rehabilitation process. The power spectral density imaging and formant frequencies extraction methods were adopted. The model of vocal tract was based on statistical, autoregressive process of speech production. The transversal filter and adaptive algorithm were implemented to estimate the transfer function of resonance cavities. The research is concerned with measurements of vowel articulation parameters, especially F1 and F2 formant frequencies. The significant difference of pathological and normal voice in vowel space separation has been presented. The authors found that formants in pseudowhisper speech are more pronounced while articulating vowel after consonant than for sustained vowel.