Abstract: The invention utilizes the fact that anyone with normal color vision has the ability look at a scene on a video display and recognize a black area if one is present; a white area if one is present, and face or flesh areas if a person is present. It is also easy to recognize blond hair, subjects that are opaque, subjects that are semi-transparent, and subjects that are bright green. The aforesaid abilities to recognize luminance and color characteristics of elements within a video scene are used in conjunction with the invention to produce ideal composite images by utilizing of a set of equations that incorporate a knowledge of color science, of video and existing compositing techniques. These equations are used to make adjustment decisions to produce the best possible composite image. The equations are used to compute certain constant values utilized in the existing compositing techniques.

Abstract: A method and apparatus used in the field of image compositing which eliminates the need to obtain an original clear frame of the backing during production, by synthesizing during post production a clear frame of the backing from a frame of the foreground scene that includes the subject as well as the backing. This synthetic clear frame eliminates the problems of obtaining a registered clear frame during production, and thereby permits the ready application of nonuniformity correction to image compositing in both motion pictures and graphic arts. The invention is also directed to a method and apparatus used in the field of image compositing which reduces the processing time for developing the inhibit signal that prevents the corrections from being applied to the subject, the control signal E.sub.c, and a number of other functions that are computed from the colored backing.

Abstract: The invention is a method used with a system for compositing a foreground scene including a subject before a nonuniformly illuminated colored backing, and a background scene, and where the nonuniformity is nonlinear from side to side and/or nonlinear from top to bottom. A window is employed to mask unwanted areas outside of, or on, the colored backing and one or more window edges form a visible join line where the window edges join the backing. The visible join line is made nonvisible without affecting the subject by a horizontal and vertical linear interpolation method for obtaining backing corrections that cause the backing level control signal to be uniform at the window edges and match an assigned window signal level.

Abstract: A method and apparatus used in the field of image compositing which eliminates the need to obtain an original clear frame of the backing during production, by synthesizing during post production a clear frame of the backing from a frame of the foreground scene that includes the subject as well as the backing. This synthetic clear frame eliminates the problems of obtaining a registered clear frame during production, and thereby permits the ready application of nonuniformity correction to image compositing in both motion pictures and graphic arts. The invention is also directed to a method and apparatus used in the field of image compositing which reduces the processing time for developing the inhibit signal that prevents the corrections from being applied to the subject, the control signal E.sub.c, and a number of other functions that are computed from the colored backing.