Vision Based Hand Gesture Interfaces for Wearable Computing and ...

Chapter 1. Introduction
cannot be larger than the hardware, the input space observable with a camera is
not limited by the camera’s form factor. This property of “device-external inter-
faces” is of increasing importance to ever-shrinking portable electronics. However,
dealing with person-specific variations, cluttered backgrounds, changing lighting
conditions, camera specifics, rapid relative motion, and hard real-time require-
ments has so far prevented vision-based interfaces (VBI) from achieving robust-
ness and usability in settings other than the lab environment. Recently, Sony’s
EyeToy (a full-body VBI for the PlayStation2) and Canesta’s virtual keyboard
(type on a keyboard projected onto any flat surface) have proven that consumer-
grade applications have become feasible. Yet, they still are very limited in their
interaction capabilities and the keyboard requires customized hardware.
3