1. Introduction
To achieve effective surveillance, a large number of cameras are often used for wide-area coverage. Once suspicious persons/activities have been identified through video analysis, selected cameras ought to be able to obtain closeup views of these suspicious subjects for further scrutiny and identification (e.g., to obtain a close-up view of the license plate of a car or the face of a person). These two requirements, a large field-of-view and selective focus-of-attention, place conflicting constraints on the system configurations and camera parameters.