In this paper we describe a method to support interaction with a cellphone based projectorcamera system. We describe a novel approach that uses a technique known in Computer Vision as structured light. It is based on projecting a pattern of light with known geometric properties onto a scene while imaging it with a camera. The distortions of the known pattern in the resulting image are due to the scene geometry which can be readily estimated. The main contribution of this paper is that the structure is created as consequence of the way raster-scan, laser-based microprojectors operate, and is in fact invisible to the user. The structure of the projected light is sensed through careful synchronization within the camera-projector system and is imperceptible to the user. In this paper we describe the technique, and test it with a cell-phone based application that exploits this method while providing a natural interactive environment with no additional special equipment. The system enables ...
Christopher Richard Wren, Yuri A. Ivanov, Paul A.