Vocal tone analysis for identification of stuttering levels based on Tamil syllable

Abstract

Speech is the most unique feature of humans and it is the basic mode of verbal communication. Among all, a few people face hurdles in producing normal speech because of various types of speech disorders. Stuttering is one of the disorder types mainly characterized by repetition of syllables or words and involuntary interruption during the speech. One of the unsolved problems in the realm of fluency disorder is the level identification, based upon the patient’s utterance before and after the speech therapy. The main objective of the paper is to perform analysis of vocal tone to identify the major differences between a normal, moderate and severely stuttered speech, particularly for the Tamil spoken language. The stutter speech vocal tone analysis involves envelope detection based on Hilbert transform has been computed from the input of normal and stuttered speech waves in which by applying normalization to the spectrum and cepstrum of the obtained signal considering only Tamil syllable as input. The experimental outcomes are given as subjective evaluation in three categories of speech signals which results people affected by severe stuttering having low vocal tone than moderate and normal stuttering speech.