SIGGRAPH, San Diego - Performance-capture studio Mova and Gentle Giant Studios have unveiled a 3D Zoetrope that uses persistence of motion to bring to life a series of 3D models of an actor’s face captured live by Mova’s Contour Reality Capture System in Booth 1229 at SIGGRAPH 2007. Two-dimensional Zoetropes, a precursor to motion-picture technology, have been around since the 1800s, and recently 3D Zoetropes have shown animated characters in motion; yet, the 3D Zoetrope on display at SIGGRAPH is the first to show a live-action, natural 3D surface in motion. The resulting effect is a physical sculpture of a speaking human face that comes to life with perfect motion, faithful to the original actor’s performance down to a fraction of a millimeter.
“Just as the 2D Zoetrope offered a glimpse of the coming future of full-length 2D movies, in our lifetimes we'll be seeing not only 3D live-action movies, but 3D interactive experiences that look as physically real as this 3D Zoetrope,” says Steve Perlman, founder and president of San Francisco-based Mova. “Contour Reality Capture will eliminate the restriction of a single camera viewpoint, allowing us to freely move around and into a live-action scene, while maintaining complete photorealism.”
“The 3-D Zoetrope is an example of capturing a live performance, digitizing it, and then returning to the physical form to create a type of real-time, stop motion animation,” says Brian Sunderlin, vice president of operations of Gentle Giant Studios in Burbank, Calif. “Gentle Giant Studios provides an integral component to visual effects creation for feature film via 3D scanning of actors. Combined with the revolutionary process that is the Mova Contour Reality Capture System, we envision a seamless integration of true, motivated performances that will wow audiences worldwide.”
The Zoetrope on display at SIGGRAPH consists of thirty 3D models of a face in motion. The models spin on a wheel and a strobe light illuminates each as it passed by a viewing window, much as still frames projected intermittently are perceived as a moving image. To the viewer, it looks like one 3D face in continuous motion.
Mova used the Contour Reality Capture System to capture the live performance of an actor using an array of cameras with shutters synchronized to lights flashing over 90 times per second, beyond the threshold of human perception. The glow from phosphorescent (glow in the dark) makeup sponged onto the actor is captured by the camera array. Triangulation and frame-by-frame tracking of the 3D geometry is then used to produce more than 100,000 polygons to create a 3D face.
Gentle Giant Studios used the captured 3D surface geometry and formed 30 individual models with the help of a 3D stereolithography printer, which creates the models layer-by-layer using a plastic resin. Gentle Giant designed and fabricated the actual Zoetrope mechanism. The apparatus is presented in an enclosure at SIGGRAPH to keep out extraneous light with a window to look in to see the 3D sculpture in motion.
Contour’s high-definition, 3D volumetric capture of the action can be imported, modified, manipulated, or retargeted to other characters using off-the-shelf CGI animation software. Contour can quickly and easily import true human behavior in all its distinct complexity into the virtual realm and works well with both marker-based motion capture and key frame animation systems.