The application of principal-components spectral analysis to sensory aids for the hearing impaired

Abstract

In order to present speech information through an alternate sensory modality—such as touch or vision—extensive processing of the speech signal is required. This processing should represent a large amount of speech information with a small number of slowly varying parameters. These parameters should be relatively speaker independent, robust in the presence of noise, and closely linked to the perceptually important features of speech spectra. One such set of parameters are speech spectral principal components. In this paper we will discuss the application of principal-components analysis of speech spectra to speech recoding for use with sensory aids. A brief overview of the analysis procedure will be included. An interpretation of principal components, and a comparison with other speech parameters such as speech formants, will be presented. Both potential benefits and drawbacks of this analysis procedure will be discussed. In addition, the implementation of a vowel articulation training aid based on principal components will be presented. Although the vowel training aid utilizes a visual display format, with color as a primary information-bearing parameter in the display, the procedure used for obtaining principal components applies equally well to a tactile aid.