| 摘要 |
PROBLEM TO BE SOLVED: To send a sound collection signal easy to listen while keeping a depth perception between a microphone and a speaker. SOLUTION: In an automatic gain control method with which an amplification factor is determined so that a sound collection signal level obtained in a microphone becomes a preset desired level, and a sound collecting signal is amplified to the desired level with the amplification factor, two microphones are disposed within a common sound field, short-time spectrum of each of sound collecting signals collected by these two microphones is determined, a ratio of an echo sound component occupying each sound collecting signal is estimated from the short-time spectrum, a correction gain is calculated from this ratio, and the level of the sound collecting signal amplified to the desired level is corrected by the correction gain. COPYRIGHT: (C)2006,JPO&NCIPI |
