Researchers create three- dimensional human face

By STEVEN JONES
Contributing Writer
They will look, move and speak like humans. They may replace humans as stuntmen and extras. They aren't people, but they're the next best thing human models indistinguishable from their real-life counterparts. And they are the ultimate goal of USC's largest research project.

While such models are still a thing of the future, the Institute for Creative Technologies Graphics Lab in Marina del Rey has made great strides during the three-year development of the $45 million project.

Lightstage 2, one of the lab's innovations, creates a 3-D model of the face, said Paul Debevec, executive producer of Graphics Research for ICT.

The procedure takes hundreds of photographs of a human face from every possible angle in just a few seconds. The subject sits in a chair while a curved arm mounted with light-emitting diodes (LEDs) rotates them at high speed. Then, during a process called active vision, the device makes a geometric model of the face using the pictures from video cameras. The two-part process takes about two minutes.

During the initial stage of photography, the skin's reflective qualities are retained by virtue of the use of so many perspectives. Active vision tends to distort the face, adding peaks and valleys to the surface of the skin.

The pictures taken in the first phase can reduce the distortion. A technique called photometric stereo combines the data from both phases and to allow an accurate reading of the position of the skin's surface all around the face.

Now that faces have been reproduced, full-body models are expected within a year. In three years, multiple digital models will interact with each other on an artificial set, Debevec said.

The set will also be created entirely within a computer. Debevec's next prototype, Lightstage 3, will be able to reproduce an entire environment, whether it be St. Peter's Basilica or the Grand Canyon, by recreating its light patterns

The Lightstage 3 will be a sphere with LEDs at every crevice. Each light source will contain red, green, and blue light, whose amounts can be adjusted to produce the desired color. Best of all, it will be fairly cheap to develop, as most of its components are inexpensive light sources.

These breakthroughs could have a tremendous impact in cinema.

This summer's "Final Fantasy: The Spirits Within" was made using very similar technology, and there is speculation that someday soon, human actors may be replaced by artificial counterparts. An article on Internet Movie Database before "Final Fantasy's" release quoted a Hollywood source who speculated that "a lot of directors are going to fall in love with these computer actors because they're cheap and reliable."

However, many feel that real thespians are a long way from being replaced by "robo-actors."

"I don't think I would ever use the computer to create a human character," George Lucas, director of "Star Wars" said during a recent online interview "It just doesn't work. You need actors to do that."

Gordie Haakstad, a senior majoring in cinema-television production, agrees with Lucas that "I don't think it'll ever replace human actors. There's still an actor underneath a performance."

But many agree with freshman film production major Lawson Deming, who feels that the advent of mechanical actors, "regardless of whether it's good or not, is inevitable."

It is important to note that putting movie stars out of a job is not the ICT's goal.

The most exciting part of the rendering breakthrough is "a computer graphics model of their face that we could stick onto a video game character's head, or composite into a movie frame for a special effects shot," according to Jonathan Cohen, author of the ICT's Web site's article, "Realistic Human Face Scanning and Rendering."

Opening a true emotional connection is only possible if an audience is watching a human actor, Debevec said.

"I think we'll be able to replace human extras," he added, explaining that it would be more practical to use computer-generated workers without face, physical or spatial limitations.

Many other ICT projects focus, on the creation of more realistic army simulations, comparative to the "Holodeck" on TV's "Star Trek." Much of the role of the School of Cinema-Television will come in scripting the scenarios for training exercises.

Debevec and his team envision a future without limits with technology for applications in "everything from training to education to entertainment," he said.

Copyright 2001 by the Daily Trojan. All rights reserved.
This article was published in Vol. 144, No. 08 (Friday, September 7, 2001), beginning on page 1 and ending on page 3.