Apparatus, method and program for processing acoustic signal, and recording medium in which acoustic signal, processing program is recorded

An acoustic signal processing method, comprising:

• inputting n acoustic signals including voice from a sound source, the n acoustic signals being captured at n different points (n is a natural number 3 or more);
• resolving each of the acoustic signals into a plurality of frequency components to obtain n pieces of frequency resolved information including phase information of each frequency component;
• computing phase difference between a pair of pieces of frequency resolved information in each frequency component with respect to m pairs of pieces of frequency resolved information different from each other in the n pieces of frequency resolved information (m is a natural number 2 or more), and generating m pieces of two-dimensional data in which a frequency function is set at a first axis and a function of the phase difference is set at a second axis;
• detecting predetermined graphics from each piece of the two-dimensional data;
• generating sound source candidate information including at least one of the number of a plurality of sound source candidates, a spatial existence range of each sound source candidate, and the frequency component of the acoustic signal from each sound source candidate based on each of the detected graphics, and generating corresponding information indicating a corresponding relationship between the pieces of sound source candidate information;
• and
• generating sound source information including at least one of the number of sound sources, the spatial existence range of the sound source, an existence period of the voice, a frequency component configuration of the voice, amplitude information on the voice, and symbolic contents of the voice based on the sound source candidate information and corresponding information which are generated by the sound source candidate information generating device.

An acoustic signal processing program, recorded on a computer readable storage medium, the program comprising:

• means for instructing a computer to input n acoustic signals including voice from a sound source, the n acoustic signals being captured at n different points (n is a natural number 3 or more);
• means for instructing the computer to resolve each of the acoustic signals into a plurality of frequency components to obtain n pieces of frequency resolved information including phase information of each frequency component;
• means for instructing the computer to compute phase difference between a pair of pieces of frequency resolved information in each frequency component with respect to m pairs of pieces of frequency resolved information different from each other in the n pieces of frequency resolved information (m is a natural number 2 or more), and to generate device generating m pieces of two-dimensional data in which a frequency function is set at a first axis and a function of the phase difference is set at a second axis;
• means for instructing the computer to detect graphics which is previously determined from each piece of the two-dimensional data;
• means for instructing the computer to generate sound source candidate information including at least one of the number of a plurality of sound source candidates, a spatial existence range of each sound source candidate, and the frequency component of the acoustic signal from each sound source candidate based on each of the detected graphics, and to generate corresponding information indicating a corresponding relationship between the pieces of sound source candidate information;
• and
• means for instructing the computer to generate sound source information including at least one of the number of sound sources, the spatial existence range of the sound source, an existence period of the voice, a frequency component configuration of the voice, amplitude information on the voice, and symbolic contents of the voice based on the sound source candidate information and corresponding information which are generated by the sound source candidate information generating device.