| 摘要 |
PROBLEM TO BE SOLVED: To highly accurately estimate a noise component of a sound signal even when the noise component fluctuates.SOLUTION: An index computation section 42 computes a confidence level CN(k,m) per unit period being an index of probability that a respective unit period of a sound signal corresponds to a noise component, in accordance with a disparity between a first index value P1(k,m) which follows time changes of power|X(k,m)|of each observation component X(k,m) of the sound signal containing a target sound component and the noise component, and a second index value P2(k,m) which follows the time changes of power|X(k,m)|at low followability compared to the first index value P1(k,m). An estimation processing section 44 generates an estimated noise component N(k,m) from the observation component X(k,m) by utilizing the confidence level CN(k,m) per unit period computed by the index computation section 42. |
