Jonathan T. Foote

Capturing and presenting shared multiresolution video

We present a framework, motivated by rate-distortion theory and the human visual system, for optimally representing the real world given limited video resolution. To provide users with high fidelity views, we built a hybrid video camera system that combines a fixed wide-field panoramic camera with a controllable pan/tilt/zoom (PTZ) camera. In our framework, a video frame is viewed as a limited-frequency representation of some true image function. Our system combines outputs from both cameras to construct the highest fidelity views possible, and controls the PTZ camera to maximize information gain available from higher spatial frequencies. In operation, each remote viewer is presented with a small panoramic view of the entire scene, and a larger close-up view of a selected region. Users may select a region by marking the panoramic view. The system operates the PTZ camera to best satisfy requests from multiple users. When no regions are selected, the system automatically operates the PTZ camera to minimize predicted video distortion. High-resolution images are cached and sent if a previously recorded region has not changed and the PTZ camera is pointed elsewhere. We present experiments demonstrating that the panoramic image can effectively predict where to gain the most information, and also that the system provides better images to multiple users than conventional camera systems.

The convertible podium: a rich media teaching tool for next-generation classrooms

The Convertible Podium is a central control station for rich media in next-generation classrooms. It integrates flexible control systems for multimedia software and hardware, and is designed for use in classrooms with multiple screens, multiple media sources and multiple distribution channels. The built-in custom electronics and unique convertible podium frame allows intuitive conversion between use modes (either manual or automatic). The at-a-touch sound and light control system gives control over the classroom environment. Presentations can be pre-authored for effective performance, and quickly altered on the fly. The counter-weighted and motorized conversion system allows one person to change modes simply by lifting the top of the Podium to the correct position for each mode.The Podium is lightweight, mobile, and wireless, and features an onboard 21 LCD display, document cameras and other capture devices, tangible controls for hardware and software, and also possesses embedded RFID sensing for automatic data retrieval and file management. It is designed to ease the tasks involved in authoring and presenting in a rich media classroom, as well as supporting remote telepresence and integration with other mobile devices.