Driven by the increasing demand for photorealistic computer-generated images, graphics is currently undergoing a substantial transformation to physics-based approaches which accurately reproduce the interaction of light and matter. Progress on both sides of this transformation -- physical models and simulation techniques -- has been steady but mostly independent from another. When combined, the resulting methods are in many cases impracticably slow and require unrealistic workarounds to process even simple everyday scenes. My research lies at the interface of these two research fields; my goal is to break down the barriers between simulation techniques and the underlying physical models, and to use the resulting insights to develop realistic methods that remain efficient over a wide range of inputs.
I will cover three areas of recent work: the first involves volumetric modeling approaches to create realistic images of woven and knitted cloth. Next, I will discuss reflectance models for glitter/sparkle effects and arbitrarily layered materials that are specially designed to allow for efficient simulations. In the last part of the talk, I will give an overview of Manifold Exploration, a Markov Chain Monte Carlo technique that is able to reason about the geometric structure of light paths in high dimensional configuration spaces defined by the underlying physical models, and which uses this information to compute images more efficiently.
Biography: Wenzel Jakob is a Marie Curie Postdoctoral Fellow at ETH Zürich in the Institute for Visual Computing. He obtained his Ph.D. in 2013 under the supervision of Dr. Steve Marschner at Cornell University and conducted his undergraduate studies at the Karlsruhe Institute of Technology. Wenzel's experience includes research and development work at Disney Research Zurich and Weta Digital, and he is the lead developer of Mitsuba, a research-oriented open source rendering system that has become a popular research platform in rendering and appearance modeling.