Signal processing device, signal processing method, and computer program product

A signal processing method comprising:

• acquiring a first acoustic signal and a second acoustic signal;
• calculating a first background sound signal in which a speech signal is removed, based on the first acoustic signal and the second acoustic signal;
• generating a first reference signal from at least one of the first acoustic signal and the second acoustic signal;
• extracting a second background sound signal by removing a speech signal from the first reference signal;
• calculating a first similarity indicating a degree of similarity between feature data of the first background sound signal and feature data of the second background sound signal;
• and
• calculating a weighted sum of the first background sound signal and the second background sound signal in such a way that a greater weight is given to the first background sound signal as the first similarity is higher and a greater weight is given to the second background sound signal as the first similarity is lower.

A computer program product comprising a computer-readable medium containing a program executed by a computer, the program causing the computer to execute:

• acquiring a first acoustic signal and a second acoustic signal;
• calculating a first background sound signal in which a speech signal is removed, based on the first acoustic signal and the second acoustic signal;
• generating a first reference signal from at least one of the first acoustic signal and the second acoustic signal;
• extracting a second background sound signal by removing a speech signal, from the first reference signal;
• calculating a first similarity indicating a degree of similarity between feature data of the first background sound signal and feature data of the second background sound signal;
• and
• calculating a weighted sum of the first background sound signal and the second background sound signal in such a way that a greater weight is given to the first background sound signal as the first similarity is higher and a greater weight is given to the second background sound signal as the first similarity is lower.