| Popis: |
Coding (i.e., analysis and resynthesis) of speech signals on the basis of physiological models of speech production mechanisms has received considerable attention during the past several years. One of the reasons for this renewed interest is that the known coding algorithms give unacceptably poor quality of speech at low bit rates (e.g., at 2400 bits/s). A coding scheme that mimics human speech production may have advantages at such low bit rates. Basically, three aspects of speech production need to be modeled. First, the geometry of the vocal and nasal tracts needs to be parametrized. Second, a model must be selected to describe wave propagation in the tract. Finally, the sound sources (vocal cords and turbulent airflow) and their interactions with the tract must be modeled. In this talk the current models being used for each of these categories will be briefly described, and the way in which these models are employed for coding will also be described. Also, the use of such models for text‐to‐speech synthesis will be mentioned. Finally, some examples of speech produced by such models, both from text as well as by analysis and resynthesis of a given speech utterance will be played. |
