Patent ID: 7475011
Filing Date: 2009-01-06
Classification: G10L

Abstract:
1. A method of selecting a value for a component of a vocal tract resonance vector, the method comprising: converting a speech signal into an observed feature vector; quantizing the vocal tract resonance vector search space so that the vocal tract resonance vector is limited to a set of allowed values; selecting static values for the components of the vocal tract resonance vector; determining a plurality of values for a function of the vocal tract resonance vector, each value of the function representing a simulated feature vector and each value of the function determined using a different value for one component of the vocal tract resonance vector while using the static values for all other components of the vocal tract resonance vector; for each value of the one component, determining a probability of an observed feature vector based on the observed feature vector, the value of the function determined using the value of the one component in the vocal tract resonance vector, and a mean of a residual model that models the difference between observed feature vectors and simulated feature vectors, to form a plurality of probabilities; and selecting a value for the one component based on the plurality of probabilities without determining a probability for all allowed values of the vocal tract resonance vector.