Patent ID: 8218786
Filing Date: 2012-07-10
Classification: H04R

Abstract:
1. An acoustic signal processing apparatus comprising: an acoustic signal inputting unit configured to input a plurality of acoustic signals obtained by a plurality of microphones arranged at different positions; a frequency decomposing unit configured to respectively decompose each acoustic signal into a plurality of frequency components, and for each frequency component, generate frequency decomposition information for which a signal level and a phase have been associated; a phase difference computing unit configured to compute a phase difference between two predetermined pieces of the frequency decomposition information, for each corresponding frequency component; a two-dimensional data converting unit configured to convert into two dimensional data made up of point groups arranged on a two-dimensional coordinate system having a frequency component as a first axis and a phase difference as a second axis; a voting unit configured to perform Hough transform on the point groups, generate a plurality of loci respectively corresponding to each of the point groups in a Hough voting space, and when adding a voting value to a position in the Hough voting space through which the plurality of loci passes, perform addition by varying the voting value based on a level difference between first and second signal levels respectively indicated by the two pieces of frequency decomposition information; and a shape detecting unit configured to retrieve a position where the voting value becomes maximum to detect, from the two-dimensional data, a shape which corresponds to the retrieved position, which indicates a proportional relationship between the frequency component and the phase difference, and which is used to estimate a sound source direction of each of the acoustic signals.