A COMPARISON AND EVALUATION OF MOTION INDEXING ...

CHAPTER 1
INTRODUCTION
Animation is a way to produce the notion of motion using a sequence of still
forms. In general, digital animation is performed by rapidly displaying a sequence of
images of 2-D or 3-D artwork or model positions, with a small change in them, which
creates an optical illusion of motion. The computer animation can be categorized into
2-D and 3-D animation. 3-D computer animation can be of two types: Keyframing
and Motion-based animation. Motion indexing is related to the reuse of motion
capture data in the motion-based animation domain. A brief survey on animation
can be found in Appendix A.
A ’White Paper’ on motion Capture by Scott Dyer, Jeff Martin, and John Zu-
lauf [1] explains that motion capture ”involves measuring an object’s position and
orientation in physical space, then recording that information in a computer-usable
form. Objects of interest include human and non-human bodies, facial expressions,
camera or light positions, and other elements in a scene.” Motion capture (mocap)
is a way of digitizing the motion which can be useful in the fields of music, fine
art dance/performance, sign language, gesture recognition, rehabilitation/medicine,
biomechanics, special effects for live-action films, and computer animation of all types,
as well as in defense and athletic analysis training. Motion based animation is pro-
duced by mapping this captured motion into the animated character’s motion. The
brief history, procedure of motion-based animation, and different motion capture
technologies are explained in Appendix B.
1