A computing system selects a portion of data of an unknown work and detects each event in the portion of data of the unknown work. An event is a perceptual occurrence in a work successively positioned in time. The system determines an event metric between each successive event in the portion of data in the unknown work and generates a list of event metrics between the events for the unknown work. The system compares the list of event metrics for the unknown work to a list of event metrics for a known work and determines the unknown work is a copy of the known work responsive to a match between the list of event metrics of the unknown work and the list of event metrics for the known work.