A Technique for Analysing Voice Quality in Pathological and Normal Speech

Abstract

A technique for voice source analysis is described which is currently being used to study voice quality variation, in dysphonic and normal speakers. The analysis technique involves a two-step procedure. The first, inverse filtering of the speech pressure waveform, yields the differential glottal flow. The settings for the inverse filter are initially estimated using a pitch-synchronous semi-automatic procedure based on the covariance method of LPC. The filter is then interactively edited on a pulse-by-pulse basis to correct for errors to which current automatic procedures are prone. The second step in the analysis involves matching a voice source model (the Liljencrants-Fant model) to the output of the inverse filter, again on a pulse-by-pulse basis. This allows quantification and comparison of the salient voice source characteristics. An illustration of some voice quality variation in normal and dysphonic speech is presented.

Exploring the prosody of affective speech

“…The chosen exemplars were then manually inverse-filtered and the resulting estimate of the voice source signal was modelled using the Liljencrats-Fant (LF) model (Fant, Liljencrants and Lin, 1985). For details on the software system and the techniques used, see Ní Chasaide, Gobl and Monahan (1992) and Gobl and Ní Chasaide (2010). The LF model is a mathematical glottal flow model that allows extraction of voice source parameters.…”

Global waveshape parameter Rd in signaling focal prominence: Perceptual salience in the absence of f0 variation

“…The utterance was elicited with broad focus (with the focal prominence realized by the speaker on YEAR) and was recorded as part of another study (Gobl et al, 2015), where further versions of the sentence with a focal accent on the syllables WAY and YEAR were also obtained and source characteristics analyzed. The utterance was manually inverse filtered using interactive inverse filtering software (Ní Chasaide et al, 1992;Gobl and Ní Chasaide, 1999). Voice source parameterization was subsequently conducted using the Liljencrants-Fant (LF) model (Fant et al, 1985).…”