ABOUT ANIMATION: The term animation refers generally 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. Geometric 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."
HOW DO YOU ANIMATE A LIVE ACTOR? 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.