Instant messages sent by a viewer of a video while the video is perceivable to the viewer may be monitored. An event of interest occurring in the video may be identified based on the monitored instant messages. Metadata that describes the event of interest may be generated and assigned to the video....http://www.google.ca/patents/US7624416?utm_source=gb-gplus-sharePatent US7624416 - Identifying events of interest within video content
