Breakthrough in motion-capture tech

Traditional motion-capture techniques use cameras to meticulously record the movement of actors inside studios, enabling these movements to be translated into digital models. However, by turning the cameras around and mounting almost two dozen outward-facing cameras on the actors, scientists at Disney Research, Pittsburgh (DRP), and Carnegie Mellon University (CMU) have shown motion-capture can be carried out almost anywhere—in natural environments, over large areas and outdoors.

Motion-capture makes possible scenes such as those in Pirates of the Caribbean: Dead Man's Chest, where the movements of actor Bill Nighy were translated into a digitally-created Davy Jones with octopus-like tentacles forming his beard. Body-mounted cameras enable the capturing of motions such as running outside or swinging on monkey bars, which would be difficult, if not impossible, otherwise, said Takaaki Shiratori, a post-doctoral associate at DRP. “This could be the future of motion-capture,” Shiratori said in a press statement. As video cameras become smaller and cheaper, “I think anyone would be able to carry out motion-capture in the not-so-distant future,” he said.

The researchers created computerised models derived from actors Rs faces that reflect a full range of natural expressions, while also giving animators the ability to manipulate facial poses. They have developed a method that not only translates the motions of actors into a 3D face model, but also sub-divides them into facial regions that enable animators to intuitively create the poses they need.

Previous data-driven approaches resulted in models that capture motion across the face as a whole. The new models were created by recording facial motion capture data from professional actors. To cover the whole face, 320 markers were applied to enable the camera to capture facial motions during the performances.

The data were then anal-ysed using a mathematical method that divided the face into regions on correlations between points that tend to move in concert with each other.