PARAMETER ESTIMATION DEVICE FOR MASK ESTIMATION, PARAMETER ESTIMATION METHOD FOR MASK ESTIMATION, AND PARAMETER ESTIMATION PROGRAM FOR MASK ESTIMATION

摘要

PROBLEM TO BE SOLVED: To improve the accuracy of speech recognition with limited learning data when performing speech recognition while adapting to a conventional environment.SOLUTION: A time frequency analysis unit 11 applies short time signal analysis to each of a plurality of observation signals to extract an observation signal for each time frequency point in a situation where an acoustic signal of a target sound source and an acoustic signal of noise coexist, and constitutes an observation vector for each time frequency point. A mask estimation unit 12 estimate a mask with regard to the acoustic signal on the basis of the observation vector and a parameter for mask estimation. A sound emphasis unit 13 multiplies the observation vector and the mask with regard to the acoustic signal of the target sound source together and thereby acquires an enhanced sound. A speech recognition unit 14 estimates the posterior probability of phoneme state of the enhanced sound using a parameter for speech recognition. A parameter estimation unit 15 estimates a parameter for mask estimation so that a distance reference between the posterior probability of phoneme state and a reference label is minimized.SELECTED DRAWING: Figure 1