On improving the decision algorithm for articulatory codebook search

This paper describes our progress on articulatory voice mimic. The objective is to achieve an articulatory voice mimic system as a basis for low bit-rate speech coding using articulatory codebooks. The articulatory codebook uses a suitable vocal tract model for generating shapes for all possible speech sounds. When building a codebook, unrealistic vocal tract shapes may be generated. In this paper, we describe the used filter based on physiological assumptions to avoid populating the codebook with such shapes. We also propose a new method for the codebook search. This method weights the prediction error for each area function parameter as a function of its contribution to match the input acoustic signal parameters. An interaction between the variations of the area function parameter is created to constraint the articulatory trajectory, which improves the search and increases the output speech quality of the voice mimic system.