In one aspect, the invention divides an audio signal into auditory events,
each of which tends to be perceived as separate and distinct, by
calculating the spectral content of successive time blocks of the audio
signal (5-1), calculating the difference in spectral content between
successive time blocks of the audio signal (5-2), and identifying an
auditory event boundary as the boundary between successive time blocks
when the difference in the spectral content between such successive time
blocks exceeds a threshold (5-3). In another aspect, the invention
generates a reduced-information representation of an audio signal by
dividing an audio signal into auditory events, each of which tends to be
perceived as separate and distinct, and formatting and storing
information relating to the auditory events (5-4). Optionally, the
invention may also assign a characteristic to one or more of the auditory
events (5-5).