Acoustical analysis for voice disorders

Glottal sound waveforms were derived by an inverse filtering method from sustained vowels uttered by 217 patients of laryngeal diseases and by 20 normal speakers. Various parameters which indicate individual characteristics were extracted from autocorrelation function, correlograms of time series of fundamental period and peak amplitude in each fundamental period, and spectral envelope of the glottal sound waveform. Then, interdependency among the acoustical parameters and the relation between those and medical parameters utilized in diagnosis were examined by principal-component analysis. Using canonical analysis, classification of some laryngeal diseases was attempted based on those acoustical parameters.