Video content characterization and compaction for digital library applications

In digital libraries and the Internet, large amount of data in various modalities has to be transmitted and delivered across the networks, and is subject to bandwidth constraints and network congestion. Among all multimedia data, video is the most difficult to handle, both in terms of its size and the scarcity of tools and techniques available for efficient delivery, storage and retrieval. Providing tools to help users search and browse large collections of video documents is important. Equally important are the means to deliver and present the essence of video content to the user without noticeable delay. In this paper, we focus on the characterization of video by means of automatic analysis of its visual content and the compact presentation of the underlying story content built upon the derived characteristics. We develop models to capture and characterize video by temporal events, namely, dialogues, actions and story units. We then present these events using succinct visual summaries that depict and differentiate the underlying dramatic elements in an intuitive manner. The combination of video characterization and visual summary offers significant compaction of data size in video far beyond the numbers achieved by traditional video compression, while retaining essential meanings and semantics of the content, and is particularly useful for digital library and Internet applications.