TARGET VOICE EXTRACTION METHOD, TARGET VOICE EXTRACTION DEVICE AND TARGET VOICE EXTRACTION PROGRAM

To precisely extract target voice in environment where various background noises are mixed.SOLUTION: A keyword detection section 11 detects that a keyword is spoken on the basis of an inputted sound signal, and calculates a keyword section being a time section when the keyword is spoken. A space covariance calculation section 12 calculates a target signal space covariance matrix under noise, which is a space covariance matrix on the basis of the sound signal of the keyword section, and calculates a noise space covariance matrix being the space covariance matrix on the basis of the sound signal of the prescribed time section except for the keyword section. A noise suppression section 13 calculates a noise suppression filter on the basis of the target signal space covariance matrix under noise and the noise space covariance matrix, and applies the noise suppression filter to the inputted sound signal to extract a target voice.SELECTED DRAWING: Figure 1