An Access Control Model for Video Database Systems

A novel approach for modeling access control in video data- bases is presented. The proposed access control mechanism uses both the semantics and the structural composition of video data. The unit of authorization, a video element, can either be a sequence of video frames or a video object that appears as part of a frame, e.g., the face of an anonymous person in an interview. The components of the access control model are the video elements, the potential users, and the mode of operation, e.g., viewing, or editing. Video elements are specified either explicitly by their identifiers or implicitly by their semantic con ten ts, while users are characterized by the user credentials. An algorithm is presented that determines the authorized portions of a video that a given user may acquire, given the user's credentials, the video content descriptions, and the type of requested video operations. The description of the implementation of a prototype MPEG-2 based video database system with access control are also presented.