June 2004

The World's Hottest Computer Lab

Continued from page 2

By Gregory T. Huang

Graphics Giants

Baining Guo wants less talk and more action. Guo, a former Intel researcher and now Microsoft Research Asia's graphics research manager, doesn't sit for interviews. He doesn't do chit-chat. Whether the end product is a video game, a screen saver, or a personalized cartoon rendered from a photograph, he says, graphics is a bottom-line business: either it looks good or it doesn't. His group consists of 12 staff researchers and, currently, 18 students; to examine their latest results, he walks down the hall to the open area where they all work.

A pressing problem in graphics-one of the lab's standout areas-is getting computers to animate photorealistic human faces. In today's video games, "characters' expressions look fake," says Guo. "Their faces don't move believably or naturally." It's a tough problem, for instance, to get the wrinkles around the eyes and forehead to look right using conventional techniques that simply morph and stretch the features of an image.

Guo's team demonstrates a cutting-edge solution. First they take about ten still pictures of a man's face, each capturing a different expression: eyebrows raised, nose scrunched, laughing, grimacing, and so on. Then, by dividing the face into 14 regions and more than 100 "feature points"-eyelids, tips of eyebrows, corners of lips-their software blends different combinations of the photos to create more natural simulations of new expressions. The software also modulates the image from one expression to another over a few seconds. The result: the man's face goes from looking surprised to looking disgusted in a realistic way, wrinkles and all.

Unlike the techniques used in computer-animated movies such as Toy Story, the Beijing researchers' approach requires no manual drawing of frames. That means it could be used in a video game to generate realistic-looking faces on the fly. With some additional configuration, it could also map expressions from a user's face to a virtual character's to create a personalized avatar for a role-playing game. What's more, photos of celebrities could be animated, or reanimated. "We could make Albert Einstein say, I love Windows,'" Guo deadpans. His team, though, is chasing a loftier goal that could ultimately transform moviemaking: software that generates photorealistic virtual actors in real time.

That kind of commitment to more-fundamental computer science research has earned the lab the respect of the academic community. "Microsoft Research is by far the biggest contributor to graphics in the corporate world. It's a powerhouse," says Paul Debevec, a graphics expert at the University of Southern California's Institute for Creative Technologies. The Beijing lab, in particular, has achieved "some amazing results," he adds. "It's not just, How can we make a better Xbox?'"

But in fact, a better Xbox is ultimately part of the lab's mission. Reminders that this is a business, not a researcher's playground, are never far away. In an adjoining hallway, a large corner room has its windows plastered over with opaque sheets of paper. The sign on the locked door reads, "Xbox: Confidential." Guo isn't allowed to talk about what's going on inside. "Some of our best people work in there," is all he'll say.