Abstract: A library of audio segments of a song is generated by receiving recorded tracks that include a complete performance of or a composition of unique portions and repetitive portions of the song, segmenting a select track into intervals, analyzing each interval to characterize the interval, comparing each interval with subsequent intervals of the select track to identify repetitive content in the song, identifying a select interval from a set of repeated intervals from the select track and storing the encoded representation of each of the select intervals from a corresponding set of repeated intervals in the library. Intervals can be characterized by frequency analysis, cross-correlation of a waveform, by a trained ear or by analysis of a musical notation corresponding to the song. Intervals for compression can be based on beats, that is, the time for a designated note, notes, a measure, or multiple measures. One or more unique measures can be encoded for additional compression.