Analysis of Vowel Articulation and Perception Using Acoustic Parameters

Abstract

Speech is the most basic and reliable form of communication. In signal processing, speech signal carrying the message is represented in the form of an acoustic waveform. Having an insight into acoustics of speech contributes to production and perception robustness. One of the best means to study this is by exploiting the acoustic correlates of speech sounds. In this thesis, work mainly centers on introduction of acoustic correlates of vowels and their application in speech production, perception and analysis. Study of acoustic correlates of speech sounds brings out a rigorous introduction to acoustics of speech. Vowels are sonorants and the most audible sounds of speech. All the three works in this thesis mainly focus on studies related to vowel sounds and use formants as the basic spectral cue. Minor work has been extended to nasals in the first study. Formant bandwidth, one of the crucial acoustic correlates, was extracted for oral and nasal tracts using vowel and nasal articulations respectively. The exploitation of acoustic correlates of vowels against speech performance among different categories of gender was conducted in the second study. Here, the computed formants are utilized to construct vowel space area used for the comparison. Also, the role of source-filter was analyzed in perception of vowels. This study too incorporated formants in the vocal tract response of the LP method. Studying the acoustic correlates correlates of speech sounds would greatly enhance the knowledge on acoustical aspects of speech useful in Acoustic Phonetics, Auditory Phonetics, Speech Analysis, Speech Synthesis, Speech Signal Processing, to understand and evaluate speech signal.