PROBABILITY CALCULATING APPARATUS FOR INCORPORATING KNOWLEDGE SOURCE AND COMPUTER PROGRAM

摘要

PROBLEM TO BE SOLVED: To provide a probability calculating apparatus capable of robustly calculating a probability of a phoneme of a speech signal by using available training data. SOLUTION: The probability calculating apparatus 516 calculates a probability of each of phonemes in a speech signal by using a statistical acoustic model and knowledge sources. The statistical acoustic model and the knowledge sources have a causal dependency represented by a Bayesian network (BN). The BN corresponds to a junction tree including cluster nodes and separator nodes. The apparatus 516 includes: a storage device 520 for local acoustic models R3, C1 and L3; a module for calculating observation data for each of frames; right, center and left context calculating devices 570, 572 and 574 for calculating a local probability of each of the phonemes causing the observation data by using the local acoustic models R3, C1 and L3; and a PDF calculating device 576 for calculating a probability of each of the phonemes as a function of local probabilities. COPYRIGHT: (C)2009,JPO&INPIT