A pioneering innovator in computer graphics visited campus last week to share his insights with University of Wyoming students.
Paul Debevec, who now works for Google’s virtual reality team, has received two Academy Awards for his efforts to make digital images more life-like. In particular, he focuses on the role light plays in making computer-generated images feel more real.
He described the arc of his career and showed examples of his work a talk on campus last Thursday.
“From a very young age, I always knew that I wanted to work on special effects,” he said. “I remember seeing ‘Back To The Future’ in theaters and just wondering how they got the car to fly at the end. That began my sort of obsession, to figure out how they did that.”
While in high school, Debevec found a way to replicate the effects he saw in the theater. He used simple texture-mapping software to map pictures he had taken of his own car onto a 3D model and used early video modeling software to simulate his car flying around in 3D space.
Debevec then attended college at the University of Southern California where he worked to simulate buildings in digital spaces. The work he did as a graduate assistant there became the foundation of the systems Google uses to simulate buildings on Google Earth.
Though Debevec’s simulator work was useful, he still felt there was something missing.
“I saw Jurassic Park and even though there were only six minutes of CG shots in the movie, the light in them looked so natural,” he said. “I did some research, and I found out that, rather that using some sort of algorithm to model the light, they had animators all do it by hand, and it was really tedious and expensive. I was still looking for a way to break in to movies, so I made that my goal, to figure out how to model light effectively.”
Debevec puzzled over the problem for a couple months and eventually found a novel solution. By taking a panoramic picture of a set, and then turning the light values from that picture into data, he could effectively model how much light was in a given shot and where it came from.
This technology’s first big break came on the 1999 film “The Matrix,” which used the technique in many of its outdoor shots. Since then, it has become standard practice within the film industry and has been used in blockbusters like “Avatar” and “Terminator: Salvation.”
With that problem solved, Debevec set his sights on another problem — people.
“CG modeling has always struggled to accurately present real humans,” he said. “We wanted to find a way to capture a person’s image so that they could be recreated perfectly on the screen.”
Thanks to some advances in hardware, Debevec adapted the techniques he used to make his car fly in high school to take high-fidelity pictures of actors from every possible angle, translate those images into data and recreate them in a computer program down to the pores on their skin. Debevec used this technique to digitally recreate “The Fast and Furious” actor Paul Walker after his death, as well as to help make a sculpture of an important White House figure.
“Soon after finishing the project we got a call from the Smithsonian,” he said. “They wanted us to come to D.C. and use our software to take some pictures of a VIP, and make a model for them. We got there and we spent about an hour taking pictures of Barack Obama so that the Smithsonian could have a record of his appearance.”
Currently, Debevec works for Google VR, trying to adapt his software to be used for realistic VR simulations. Debevec doesn’t know where his expertise will take him next, but he knows that he will be on the cutting edge of 3D simulation.
