Patent ID: 8438013

Claim:
A music-piece classifying apparatus comprising: a processor; frequency analyzer means implemented by the processor for subjecting an audio signal representative of a music piece inputted via an input device to frequency analysis to generate frequency component data composed of respective frequency components corresponding to time, frequency band, and component intensity; detector means implemented by the processor for detecting, with respect to the frequency component data corresponding to a prescribed portion or whole of the music piece, the frequency components satisfying a prescribed condition as effective components for each block being an interval containing a first prescribed number of the frequency components of one frequency band in a time base direction, for, in cases where the number of the effective components of said one frequency band in the block is equal to or larger than a second prescribed number, detecting said one frequency band as a sustain region, and for calculating an index of sound thickness through the use of an addition value of the component intensities of the frequency components in the sustain region in the block; feature calculator means implemented by the processor for calculating a feature quantity from at least one of (1) an average of the indexes calculated by the detector means, (2) a variance in the indexes calculated by the detector means, (3) a standard deviation in the indexes calculated by the detector means, and (4) differences between neighboring blocks in indexes calculated by the detector means; and classifier means implemented by the processor for classifying the music piece in response to the feature quantity calculated by the feature calculator means.