Tele-immersion.(Technology Information)

Tomorrow's Teleconferencing

REAL-TIME TRANSMISSION OF REAL-LIFE ENVIRONMENTS MAY BE INTERNET 2'S MOST VISIONARY APPLICATION

When Internet 2-level network performance becomes commonplace at some point in the future, which applications will make the best use of this giant leap in bandwidth? Virtual laboratories, digital libraries, and distance-independent learning are among some of the advanced applications currently being explored. Jaron Lanier, who helped lead in the development of virtual reality during the 1980s, is now guiding an attempt to validate the Net of tomorrow with a nascent technology known as tele-immersion: long distance transmission of life-size, three-dimensional synthesized scenes, accurately sampled and rendered in real time using advanced computer graphics and vision techniques. Such replication of visual content in large volumes of everyday reality should lead to more naturalistic teleconferencing work environments (and less business travel), greater fidelity in relaying news and entertainment events (high-def will seem positively low-res), and even Star Trek Holodeck-like telepresence in remote locales (beam me up, Jaron).

After three years of effort, Lanier and his colleagues are showing their first proof-of-concept demo, a three-way virtual meeting that makes today's videoconferencing look like the 8mm movies of yesteryear. At the University of North Carolina (UNC) at Chapel Hill, invited visitors can witness on two walls the life-size, real-time images of researchers seated at their desks at the University of Pennsylvania in Philadelphia, and at the Armonk, New York, laboratory of project sponsor Advanced Network & Services, where Lanier serves as the initiative's chief scientist. In what is dubbed the "tele-cubicle," a UNC participant wearing polarizing glasses and a silvery head-tracking device can move around and see a computer-generated 3D stereoscopic image of the other two teleconferencers, whereby the visual content of a block of space surrounding each participant's upper body and some adjoining workspace is essentially reproduced with computer graphics. This results in a more fully dimensional and compressible depiction of such real-world environments than is possible with existing video technology. Though the demo is far from perfect, with two-way transmissions instead of three-way, and jitters visible in the displays, it nonetheless marks the accomplishment of what Lanier characterizes as "the ultimate convergence of the real world and computer graphics."

The National Tele-immersion Initiative (NTII), as this ongoing project is known, was first proposed by Allan H. Weis, founder of Advanced Network & Services, one of the builders of the Internet's original backbone. With the proceeds from the company's sale to America Online, Advanced Network & Services became a research institution, funding work on leading-edge uses of computer network technology. Lanier was then hired and given a staff based in Armonk, along with a budget to provide grants to university researchers. Principal investigators include Henry Fuchs of UNC, Andries van Dam of Brown University, and Ruzena Bajcsy at the University of Pennsylvania. Researchers at the Naval Postgraduate School, Carnegie Mellon University, Columbia University, the University of Illinois at Chicago, and the University of Southern California were also involved with the project.

Overcoming Technical Issues

"There are quite a few difficulties involved," says Lanier. "The first is, how do you sense a remote place in real time fast enough and with the kind of quality so you can re-render it and make it look good? There you have a mixture of vision problems, graphics problems, and networking problems all in one bundle. Then beyond that, how do you create a physical viewing configuration that supports the illusion of reality?"