3-D Enhances Videoconferencing

Michael Van Belle

By 2010, the boundaries among communications, computing and broadcasting will be hard to discern. To that end, Panorama -- a cooperative project sponsored by the European Union -- presented three-dimensional telepresence systems in October at the Heinrich-Hertz Institut für Nachrichtentechnik Berlin GmbH.

With a trinocular camera setup, one potential telepresence system is based on a true 3-D reconstruction of the scene.

Such 3-D systems will allow users to feel as if they are in the same room as those with whom they are communicating without cumbersome 3-D glasses, according to Ralf Buschmann of Siemens AG in Munich, Germany, one of the member companies of Panorama. "Telepresence extends the videoconferencing concept so that participants can use nonverbal aspects of communication such as eye contact, body movements and facial expressions in the same way as they would in a face-to-face meeting," he said.

The first demonstrator system for video communication is a real-time 3-D videoconferencing system with viewpoint adaptation. It uses a stereoscopic image sequence and is based on disparity estimation and disparity-compensated interpolation of intermediate views. The intermediate views are generated according to the observer's head position, so that the user can choose his viewpoint and look around the scene he observes, Buschmann said.

These virtual views are displayed on an autostereoscopic display developed by the Heinrich-Hertz Institut and Carl Zeiss GmbH of Jena, Germany. "The participants, for the first time, really have the impression of being physically close to each other."

Using a trinocular camera setup, the second system is based on a true 3-D reconstruction of the scene, which uses explicit 3-D models defined by 3-D shape, surface color and 3-D motion parameters. Because of the computational load and its novelty, 3-D reconstruction is done by software off-line. For visualization, 3-D graphic computers generate stereoscopic images according to the observer's head position in real time.

"In the future, the developed technology will allow the design of comfortable and intuitive teleconference systems, where participants are brought together in a 3-D virtual conference room and to give the participants the impression of being physically close to each other," Buschmann said.

Target applications include videoconferencing, telemedicine and teleoperating. The autostereoscopic display is expected to be available early this year.