Motion Capture - What is it?
Motion capture is defined as "The creation of a 3D representation of a live performance." in the book Understanding Motion Capture for Computer Animation and Video Games by Alberto Menache. This is in contrast to animation that is created 'by hand' through a process known as keyframing.
Motion capture (AKA Mocap) used to be considered a fairly controversial tool for creating animation. In the early days, the effort required to 'clean up' motion capture data often took as long as if the animation was created by an animator, from scratch. Thanks to hard work by the manufacturers of motion capture systems as well as numerous software developers, motion capture has become a feasible tool for the generation of animation.
Software tools for working with motion-captured data, such as MotionBuilder , have evolved to the point where animators now have the means to edit and blend takes from multiple capture sessions and mix and match them with keyframed animation techniques; allowing great control of style and quality of final output, for anything ranging from realistic to 'cartoony' motion.