Virtual Kathakali : Gesture Driven Metamorphosis

Training in motor skills such as athletics, dance, or gymnastics is not possible today except in the direct presence of the coach/instructor. This paper describes a computer vision based gesture recognition system which is used to metamorphose the user into a Virtual person, e.g. as a Kathakali dancer, which is graphically recreated at a near or distant location. Thus this can be seen by an o -site coach using low-bandwidth joint-motion data which permits real-time animation. The metamorphosis involves altering the appearance and identity of the user and also creating a speci c environment possibly in interaction with other virtual creatures. Unlike previous approaches to gesture based virtual reality, here i) a single monochrome camera is used to track the arms, and ii) colour di erences are used to disambiguate situations where the arm is occluding the user’s body. A robust vision module is used to identify the user, based on very simple binary image processing in real time which also manages to resolve self occlusion, correct for clothing/colour and other variations among users. Gestures are identi ed by locating key points at the shoulder, elbow and wrist joint, which are then recreated in an articulated humanoid model, which in this instance, represents a Kathakali dancer in elaborate traditional dress. Unlike glove based or other gesture and movement tracking systems, this application requires the user to wear no hardware devices and is aimed at making gesture tracking simpler, cheaper, and more user friendly.