But by turning the cameras around — mounting almost two dozen, outward-facing cameras on the actors themselves — scientists at Disney Research, Pittsburgh (DRP), and Carnegie Mellon University (CMU) have shown that motion capture can occur 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. But body-mounted cameras enable capture of motions, such as running outside or swinging on monkey bars, that would be difficult — if not impossible — otherwise, said Takaaki Shiratori, a post-doctoral associate at DRP.
“This could be the future of motion capture,” said Shiratori, who will make a presentation about the new technique today (Aug. 8) at SIGGRAPH 2011, the International Conference on Computer Graphics and Interactive Techniques in Vancouver. As video cameras become ever smaller and cheaper, “I think anyone will be able to do motion capture in the not-so-distant future,” he said.
Other researchers on the project include Jessica Hodgins, DRP director and a CMU professor of robotics and computer science; Hyun Soo Park, a Ph.D. student in mechanical engineering at CMU; Leonid Sigal, DRP researcher; and Yaser Sheikh, assistant research professor in CMU’s Robotics Institute.
The wearable camera system makes it possible to reconstruct the relative and global motions of an actor thanks to a process called structure from motion (SfM). Takeo Kanade, a CMU professor of computer science and robotics and a pioneer in computer vision, developed SfM 20 years ago as a means of determining the three-dimensional structure of an object by analyzing the images from a camera as it moves around the object, or as the object moves past the camera.
In this application, SfM is not used primarily to analyze objects in a person’s surroundings, but to estimate the pose of the cameras on the person. Researchers used Velcro to mount 20 lightweight cameras on the limbs, and trunk of each subject. Each camera was calibrated with respect to a reference structure. Each person then performed a range-of-motion exercise that allowed the system to automatically build a digital skeleton and estimate positions of cameras with respect to that skeleton.
SfM is used to estimate rough position and orientation of limbs as the actor moves through an environment and to collect sparse 3D information about the environment that can provide context for the captured motion. The rough position and orientation of limbs serves as an initial guess for a refinement step that optimizes the configuration of the body and its location in the environment, resulting in the final motion capture result.
The quality of motion capture from body-mounted cameras does not yet match the fidelity of traditional motion capture, Shiratori said, but will improve as the resolution of small video cameras continues to improve.
The technique requires a significant amount of computational power; a minute of motion capture now can require an entire day to process. Future work will include efforts to find computational shortcuts, such as performing many of the steps simultaneously through parallel processing.For more information and to see a video, visit the project website:
Byron Spice | EurekAlert!
Stealth Virus for Cancer Therapy
31.01.2018 | Universität Zürich
New formulas for exploring the age structure of non-linear dynamical systems
23.01.2018 | Max-Planck-Institut für Biogeochemie
Breakthrough provides a new concept of the design of molecular motors, sensors and electricity generators at nanoscale
Researchers from the Institute of Organic Chemistry and Biochemistry of the CAS (IOCB Prague), Institute of Physics of the CAS (IP CAS) and Palacký University...
For photographers and scientists, lenses are lifesavers. They reflect and refract light, making possible the imaging systems that drive discovery through the microscope and preserve history through cameras.
But today's glass-based lenses are bulky and resist miniaturization. Next-generation technologies, such as ultrathin cameras or tiny microscopes, require...
Scientists from the University of Zurich have succeeded for the first time in tracking individual stem cells and their neuronal progeny over months within the intact adult brain. This study sheds light on how new neurons are produced throughout life.
The generation of new nerve cells was once thought to taper off at the end of embryonic development. However, recent research has shown that the adult brain...
Theoretical physicists propose to use negative interference to control heat flow in quantum devices. Study published in Physical Review Letters
Quantum computer parts are sensitive and need to be cooled to very low temperatures. Their tiny size makes them particularly susceptible to a temperature...
Let’s say the armrest is broken in your vintage car. As things stand, you would need a lot of luck and persistence to find the right spare part. But in the world of Industrie 4.0 and production with batch sizes of one, you can simply scan the armrest and print it out. This is made possible by the first ever 3D scanner capable of working autonomously and in real time. The autonomous scanning system will be on display at the Hannover Messe Preview on February 6 and at the Hannover Messe proper from April 23 to 27, 2018 (Hall 6, Booth A30).
Part of the charm of vintage cars is that they stopped making them long ago, so it is special when you do see one out on the roads. If something breaks or...
15.02.2018 | Event News
13.02.2018 | Event News
12.02.2018 | Event News
16.02.2018 | Information Technology
16.02.2018 | Health and Medicine
16.02.2018 | Physics and Astronomy