System for establishing a three-dimensional garbage matte which enables

Abstract

A new method and apparatus for creating, positioning and manipulating a garbage matte which obscures everything outside of a three-dimensional physical set or blue stage. Effectively, the garbage matte is a 'negative' of a blue stage. What is important is that the garbage matte is created either as a virtual enclosure around all virtual objects in the virtual environment, or simply as a background color of the graphics engine generating the garbage matte. In this way, the garbage matte provides extensions of blue screens which comprise the blue stage, extending all the way around and behind the television cameras. Consequently, a compositor will not include in a composited output image those physical set elements which are masked by the virtual garbage matte. The compositor will replace areas hidden by the garbage matte with image data supplied by the computer image generator which stores the virtual environment. Furthermore, it is now possible to move the virtual location of the physical set (including the television cameras) within the virtual environment without having to readjust the position of the garbage matte relative to the model by anchoring virtual objects together so as to maintain relative position relationships at all times.