Audio signal analysis

摘要

A server system 500 is provided for receiving video clips having an associated audio/musical track for processing at the server system. The system comprises a first beat tracking module for generating a first beat time sequence from the audio signal using an estimation of the signal's tempo and chroma accent information. A ceiling and floor function is applied to the tempo estimation to provide integer versions which are subsequently applied separately to a further accent signal derived from a lower-frequency sub-band of the audio signal to generate second and third beat time sequences. A selection module then compares each of the beat time sequences with the further accent signal to identify a best match.

主权项

1. Apparatus, the apparatus having at least one processor and at least one memory having computer-readable code stored thereon which when executed controls the at least one processor:
to generate a first accent signal (a1) representing musical accents in an audio signal by extracting chroma accent features based on fundamental frequency (f0) salience analysis; to generate a second, different, accent signal (a2) representing musical accents in the audio signal by using a predetermined sub-band of the audio signal's bandwidth; to estimate a first beat time sequence (bi) from the first accent signal; to estimate a second beat time sequence (b2) from the second accent signal; and to identify which one of the first and second beat time sequences (bi) (b2) corresponds most closely with peaks in one or both of the accent signal(s).