Patent ID: 8680386

Claim:
A signal processing device that identifies a piece of music from an input signal by comparing the input signal with a plurality of reference signals including only the piece of music, the signal processing device comprising: a weight distribution generating section that generates a weight distribution corresponding to a likeness to music in regions of the input signal transformed into a time-frequency domain; and a similarity calculating section that calculates degrees of similarity between a feature quantity in the regions of the input signal transformed into the time-frequency domain and feature quantities in the regions of the reference signals transformed into the time-frequency domain based on the weight distribution, wherein the similarity calculating section calculates the degrees of similarity between the feature quantity in the regions of the input signal being transformed into the time-frequency domain and corresponding to a predetermined time and the feature quantities in the regions of the reference signals being transformed into the time-frequency domain and corresponding to the predetermined time based on the weight distribution.