A Framework for Abstract Representation and Recognition of Gestures in Multi-touch Applications

Tangible user interfaces allowing multiple simultaneous contacts are by now well known as multi-touch devices. They add new dimensions to input possibilities compared with traditional single-pointer devices. At the same time, complexity of input interpretation increases, as well. Particularly recognition of predefined gestures requires sophisticated techniques to cope with multiple points of interaction. In this paper we present a novel approach for recognition of multi-touch gestures by means of a mathematical rule calculus. It allows abstract definition of multi-touch gestures. We further outline how to implement a framework to encapsulate the recognition algorithm, and demonstrate its success through a practical example obtained from an existing application.