Special Cinematographic Effects with Virtual Movie Cameras

The term "virtual camera" is often used in computer graphics, but it usually represents a mere abstraction for labeling the projection mechanism from 2D to 3D. We believe that a virtual camera should be a software entity that can be manipulated in the same way as cameramen manipulate real cameras. This article presents a model of a virtual movie camera and describes typical effects used by cameramen, including panning, tilting, tracking, zooming and spinning. Matte effects are introduced using an actorbased polygonal clipping method, and practical examples of such multiple-image effects as fades and wipes are presented.