A genetic approach for recovering vocal tract area functions from Spanish vowels
José Brito, Wladimir Rodríguez · 2005
Abstract: This paper shows how a genetic algorithm is able to recover vocal tract area functions from natural utterances. The kind of data analyzed is a subset of Spanish speech signals, concretely vowels from Venezuelan SpeechDat database of utterances, increasing novelty of the study. The method evolves parametric and real-coded representations of speech articulators, with the goal set to minimizing acoustic distance respect to the target, nat-ural SpeechDat utterances. This distance is based on signal’s formants and a measure of continuity of the area function. Furthermore, the genetic algorithm is implemented by using the multipopulation approach, seeking to accelerate convergence to a solution while keeping genetic diversity. Subsequently, best learned functions are provided as input to an articulatory speech synthesizer, in order to generate artificial utterances, potentially and acoustically similar to the natural signals. Objective and subjective tests on these artificial signals have positively verified effectiveness of the genetic approach.