A Virtual Touchscreen with Depth Recognition

While touch interfaces have become more popular, they are still mostly confined to mobile platforms such as smart phones and notebooks. Mouse interfaces still dominate desktop platforms due to their portability, ergonomic design and large number of possible interactions. In this paper we present a prototype for a new interface based on cheap consumer-level hardware, which combines advantages of the mouse and touch interface, but additionally allows the detection of 3D depth values. This is achieved by using a web cam and point light source and detecting hand and shadow gestures in order to compute 3D finger tip positions. Our evaluation shows that the concept is feasible and more powerful interactions than with traditional interfaces can be achieved. Limitations include a reduced input precision, insufficient stability of the utilised computer vision algorithms, and the requirement of a stable lighting environment.