Flashing a wink and a smirk might be second nature for some people, but computer animators can be hard-pressed to depict such an expression realistically. Now scientists at Disney Research, Pittsburgh, and Carnegie Mellon University's Robotics Institute have created computerized models derived from actors' faces that reflect a full range of natural expressions while also giving animators the ability to manipulate facial poses.
The researchers developed a method that not only translates the motions of actors into a three-dimensional face model, but also sub-divides it into facial regions that enable animators to intuitively create the poses they need. The work, to be presented Aug. 10 at SIGGRAPH 2011, the International Conference on Computer Graphics and Interactive Techniques in Vancouver, envisions creation of a facial model that could be used to rapidly animate any number of characters for films, video games or exhibits.
"We can build a model that is driven by data, but can still be controlled in a local manner," said J. Rafael Tena, a Disney research scientist, who developed the interactive face models based on principal component analysis (PCA) with Iain Matthews, senior research scientist at Disney, and Fernando De la Torre, associate research professor of robotics at Carnegie Mellon.
Previous data-driven approaches have resulted in models that capture motion across the face as a whole. Tena said these are of limited use for animators because attempts to alter one part of an expression — a cocked eye, for instance — can cause unwanted motions across the entire face. Attempts to simply divide these holistic models into pieces are less effective because the resulting model isn't tailored to the motion of each piece.
As a result, Tena said, most facial animation still depends on "blendshape" models — a set of facial poses sculpted by artists based on static images. Given the wide range of human expressions, it can be difficult to predict all of the facial poses required in a film or videogame, however. Many additional poses often must be created during the course of production.
By contrast, Tena, De la Torre and Matthews created their models by recording facial motion capture data from a professional actor as he performed sentences with emotional content, localized actions and random motions. To cover the whole face, 320 markers were applied to enable the camera to capture facial motions during the performances.
The data from the actor was then analyzed using a mathematical method that divided the face into regions, based in part on distances between points and in part on correlations between points that tend to move in concert with each other. These regional sub-models are independently trained, but share boundaries. In this study, the result was a model with 13 distinct regions, but Tena said more regions would be possible by using performance capture techniques that can provide a dense reconstruction of the face, rather than the sparse samples produced by traditional motion capture equipment.
Future work will include developing models based on higher-resolution motion data and developing an interface that can be readily used by computer animators.
About Carnegie Mellon University: Carnegie Mellon (www.cmu.edu) is a private, internationally ranked research university with programs in areas ranging from science, technology and business, to public policy, the humanities and the arts. More than 11,000 students in the university's seven schools and colleges benefit from a small student-to-faculty ratio and an education characterized by its focus on creating and implementing solutions for real problems, interdisciplinary collaboration and innovation. A global university, Carnegie Mellon's main campus in the United States is in Pittsburgh, Pa. It has campuses in California's Silicon Valley and Qatar, and programs in Asia, Australia, Europe and Mexico. The university is in the midst of a $1 billion fundraising campaign, titled "Inspire Innovation: The Campaign for Carnegie Mellon University," which aims to build its endowment, support faculty, students and innovative research, and enhance the physical campus with equipment and facility improvements.
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