Implementation of simulated annealing in unit selection for Malay text-to-speech system

Abstract

Unit selection method has become the predominant approach in speech synthesis. The quality of unit selection based concatenative speech synthesis primarily governed by how well two successive units can be joined together. Therefore, the main purpose of unit selection is to minimize the audible discontinuities. The process of unit selection is based on phonetic context and Simulated Annealing that selects units from large database with the minimization of a criterion, which is often called cost. This dissertation presents a variable-length unit selection Malay text to speech system that is capable of providing more natural and accurate unit selection for synthesized speech. To provide the capability of selecting a speech unit not only limited to phoneme, diphone or triphone but also a string of phonemes that can be matched directly to the database, unit selection methods have been implemented. The Mel Frequency Cepstral Coefficients (MFCC) as spectral parameters have been introduced in the unit selection based speech synthesis. Distance measurement is needed to measure the difference between two vectors of this speech feature. The spectral distance used is Euclidean Distance.