Digitizing actors for film and TV after death presents a unique challenge

"TechKnow" recently visited University of Southern California's Institute for Creative Technologies and Digital Domain, a Los Angeles-based visual effects company, to dive into how innovation in photography and computers help capture and digitally render real human beings.

Modern audiences are used to computer-generated imagery (CGI) in films like "Avatar." USC's ICT and Digital Domain are focused on taking CGI to a new level -- re-creating humans that are indistinguishable from the real thing.

One great example of this is David Fincher's 2008 film, "The Curious Case of Benjamin Button," in which Brad Pitt’s character is shown at various stages of life, from old age to infancy.

"A lot of people don't even realize that Brad Pitt wasn't in the first 52 minutes of that film," said Steve Preeg, an animation director with Digital Domain. "Benjamin Button" won the 2009 Academy Award for Best Visual Effects.

ICT and Digital Domain achieve these kinds of near-perfect recreations by using a light stage and photography setup that takes hundreds of thousands of pictures of actors and using that data to rebuild and/or manipulate a person's face however they may need. This includes making an actor appear older, like in "Benjamin Button," or creating a younger version of actor, which was the case with Jeff Bridges in the 2010's "TRON: Legacy."

Where the technology and art form faces a newer challenge is in trying to render the likenesses of people no longer available for capture.

Both Paul Walker and Philip Seymour Hoffman recently died without having completed film projects. Universal Pictures has said that the production of "Fast & Furious 7" will employ four body doubles and CGI to allow Walker's character to be to retired from the franchise. In the final installment of the “Hunger Games” series, "The Hunger Games: Mockingjay - Part 2," similar visual techniques may be used to complete a key scene that Hoffman hadn't been able to finish before his death in early February.

This won't be the first time audiences see faces of deceased performers come to life on screen again. In 2011, Dior released an ad marketing their fragrance "J'adore" that featured Charlize Theron roaming backstage at a runway show, casually walking past old Hollywood stars Marlene Dietrich, Marilyn Monroe, and Grace Kelly.

In 2012, people who attended the Coachella Valley Music and Arts Festival had an opportunity to see the late rapper Tupac Shakur give a live performance alongside old friends Snoop Dogg and Dr. Dre. Digital Domain was the company responsible for the project they called "Virtual 2Pac." After the hologram debuted at Coachella, social media sites lit up with talk about the performance, and sales for Shakur's discography rose 500 percent in the weeks following.

Those who use this technology must tread a fine line. Digital Domain aims to push their artists to create unique, exciting experiences without overstepping ethical boundaries. Ed Ulbrich, an executive at Digital Domain, expressed this while speaking about "Virtual 2Pac" at the SXSW Music festival in 2013. "My worry was that if we attempted this, we'd have people in the audience throwing tomatoes," he said. "Even if we got it perfect, we'd have people saying, 'How could you?'"

"Virtual 2Pac" went over well with spectators, but each new project has to be treated with caution and respect to those no longer living. The success of the final products will always be determined by those that watch these digital performances, but the capabilities of the technology will continue to expand. The human face and body remain the most complicated for animators to recreate, but work from USC and graphics houses like Digital Domain bring the film industry closer to seamless depictions every year.

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