Figure: Interactive Virtual Environment hardware.
Figure 2 demonstrates the basic components of an Interactive Space that occupies an entire room. We also refer to this kind of space as an Interactive Virtual Environment (IVE). The user interacts with the virtual environment in a room sized area (15'x17') whose only requirements are good, constant lighting and an unmoving background. A large projection screen (7'x10') allows the user to see the virtual environment, and a downward pointing wide-angle video camera mounted on top of the projection screen allows the system to track the user (see Section 2.2). A phased array microphone (see Section 2.4) is mounted above the display screen. A narrow-angle camera mounted on a pan-tilt head is also available for fine visual sensing. One or more Silicon Graphics computers are used to monitor the input devices in real-time..
Figure: An Instrumented Desktop
Another kind of Interactive Space is the desktop. Our prototype desktop systems consist of a medium sized projection screen (4'x5') behind a small desk (2'x5'--See Figure 3). The space is instrumented with a wide-baseline stereo camera pair, an active camera, and a phased-array microphone. This configuration allows the user to view virtual environments while sitting and working at a desk. Gesture and manipulation occur in the workspace defined by the screen and desktop. This sort of interactive space is better suited for detailed work.