Dynamic shadow removal from front projection displays

Abstract

Front-projection display environments suffer from a fundamental problem: users and other objects in the environment can easily and inadvertently block projectors, creating shadows on the displayed image. We introduce a technique that detects and corrects transient shadows in a multi-projector display. Our approach is to minimize the difference between predicted (generated) and observed (camera) images by continuous modification of the projected image values for each display device. We are unaware of any other technique that directly addresses this problem. Furthermore, we speculate that the general predictive monitoring framework introduced here is capable of addressing more general radiometric consistency problems such as displaysurface inter-reflections and the changes in display color and intensity due to projector bulb temperature variation. Using