| 摘要 |
PROBLEM TO BE SOLVED: To provide a noise suppression method free of a decline in a suppressed amount of noise even when there is a temporal change in noise, in which sound quality after noise suppression, therefore, does not become unnatural.SOLUTION: A noise suppression method according to the present invention includes a noise section detection step, a noise level fluctuation amount estimation step, and a noise suppression gain calculation step. The noise section detection step compares a sound pickup signal level and a noise level, and, focusing on a difference in frequency spectrum between the sound pickup signal and the noise, detects a noise section in all frequencies combined. The noise level fluctuation amount estimation step calculates a ratio of the sound pickup signal level divided by the noise level in the noise section, and estimates the amount of noise level fluctuation in which the ratio is smoothed over time. The noise suppression gain calculation step calculates, using the sound pickup signal level, the noise level, and the amount of noise level fluctuation as input, a noise suppression gain by which noise is suppressed. |
