| 摘要 |
PROBLEM TO BE SOLVED: To emphasize and output sound from a sound source present in an object direction. SOLUTION: A phase difference correction part 20 extracts discrete values of first and second observation signals generated by first and second directional microphones 10 and 11, and shifts only the phase difference in the case where a sound source is present in the object direction with respect to the discrete value of the second observation signal. A sound source direction determination part 21 calculates first and second observation power values being power values of the first and second observation signals. When at least one of the first and second observation power values is not larger than a threshold value, it is determined that the sound source is not present in the object direction and, when both the first and second observation power values are larger than the threshold value and a relative ratio of the first and second observation power values is smaller than another threshold value, it is determined that the sound source is present in the object direction. An output calculation part 22 outputs a synthesized signal of the first and second observation signals by amplifying it with a large amplification factor when the sound source is present in the object direction, and outputs the synthesized signal by amplifying it with a small amplification factor when the sound source is not present in the object direction. COPYRIGHT: (C)2009,JPO&INPIT |
