Sound source detection apparatus, method for detecting sound source, and program

An apparatus, comprising:

• circuitry that, in operation, performs operations, including:
• calculating a first correlation matrix, which corresponds to observed signals, which are acoustic signals obtained by a microphone array including two or more separately arranged microphones,
• specifying a non-scan range, which indicates a direction range within which a target sound source is not to be detected,
• estimating a second correlation matrix, which corresponds to an acoustic signal from a sound source within the non-scan range, using the first correlation matrix at a time when a spatial spectrum intensity corresponding to the acoustic signal from the sound source within the non-scan range is higher than a threshold and there is no acoustic signal from the target sound source within a scan range, which indicates a direction range within which the target sound source is to be detected,
• calculating a third correlation matrix, which corresponds to the target sound source within the scan range, by removing the second correlation matrix from the first correlation matrix, and
• calculating a first spatial spectrum on the basis of the third correlation matrix as a localization result.

A method comprising:

• calculating a first correlation matrix, which corresponds to observed signals, which are acoustic signals obtained by a microphone array including two or more separately arranged microphones,
• specifying a non-scan range, which indicates a direction range within which a target sound source is not to be detected,
• estimating a second correlation matrix, which corresponds to an acoustic signal from a sound source within the non-scan range,
• calculating a third correlation matrix, which corresponds to the target sound source within a scan range, which indicates a direction range within which the target sound source is to be detected, by removing the second correlation matrix from the first correlation matrix, and
• calculating a first spatial spectrum on the basis of the third correlation matrix as a localization result,
• wherein, in the estimating, the second correlation matrix is estimated on the basis of direction vectors obtained from the direction range of the non-scan range and a second spatial spectrum, which is a localization result immediately before the first spatial spectrum is calculated.

A non-transitory computer-readable recording medium storing a program, that, when executed by a computer, causes the computer to implement a method comprising:

• calculating a first correlation matrix, which corresponds to observed signals, which are acoustic signals obtained by a microphone array including two or more separately arranged microphones,
• specifying a non-scan range, which indicates a direction range within which a target sound source is not to be detected,
• estimating a second correlation matrix, which corresponds to an acoustic signal from a sound source within the non-scan range,
• calculating a third correlation matrix, which corresponds to the target sound source within a scan range, which indicates a direction range within which the target sound source is to be detected, by removing the second correlation matrix from the first correlation matrix, and
• calculating a first spatial spectrum on the basis of the third correlation matrix as a localization result,
• wherein, in the estimating, the second correlation matrix is estimated on the basis of direction vectors obtained from the direction range of the non-scan range and a second spatial spectrum, which is a localization result immediately before the first spatial spectrum is calculated.