ABOUT ANIMATION: The term animation generally refers to graphical displays in which a sequence of images with gradual differences results in the same effect as a photographed movie. Computer generated animations are getting more and more common, replacing hand drawn images and other special techniques. There are several ways to generate dynamic changes in computer graphics. Geometry animation is the most complex, and requires changing the geometric elements of a scene dynamically. This is also what most people generally refer to when using the term "animation," evidenced by motion pictures like "Toy Story" and "A Bug's Life."
WHAT IS MOTION CAPTURE: Motion capture cuts the costs of computer animation while creating more natural movement. Such systems work by tracking the locations of hundreds of reflective balls attached to a human actor. This permits the actor's movements to be sampled by a camera many times per second. But the digital record is limited to movements and does not include the actual appearance of the actor. They are limited in resolution to several hundred points on a human face.
HOW CONTOUR WORKS: The Contour system requires actors to cover their faces and clothes with makeup containing phosphorescent powder that is not visible under normal lighting. In a light-sealed room, the actors face two arrays of inexpensive video cameras that are synchronized to simultaneously record their appearance and shape. Scenes are lit by rapidly flashing fluorescent lights, and the cameras capture light from the glowing powder during intervals of darkness that are too short for humans to perceive. The captured images are then transmitted to an array of computers that reassemble the 3D shapes of the glowing areas. These can then be manipulated and edited into larger digital scenes using sophisticated software tools.