Image-Based Modeling involves deriving models of objects and environments based on photographs. Some techniques for recovering geometry included stereo correspondence and photogrammetry. I'll talk about Facade, an interactive photogrammetric modeling system developed at UC Berkeley, which is based on using geometric primitives to model the scene. Recent results also allow lighting-indepedent texture maps and specular properties to be derived from images, allowing scenes to be re-illuminated.
Image-Based Rendering involves generating renderings of scenes from arbitrary viewpoints based on their appearance in a set of images. Often, geometry from image-based modeling techniques is used to determine how to interpolate between available viewpoints to create synthetic camera moves.
Image-Based Lighting involves using measurements of real illumination in the real world to illuminate synthetic objects. The technique leverages high dynamic range photography, in which a series of exposures is taken with varying shutter speeds and combined into a single image that spans the full range of brightness (often exceeding 1:100,000) in a scene. Such lighting can be used to render synthetic objects into real scenes with the correct lighting, and to automatically generate the proper reflections and shadows in the scene. A device called a "light probe" for measuring incident illumination on location will be presented.
I'll show these techniques using examples from several recent animation projects, including:
The Campanile Movie, SIGGRAPH 97
Rendering with Natural Light, SIGGRAPH 98, and
Fiat Lux, SIGGRAPH 99
Information on these various projects is available at:
http://www.cs.berkeley.edu/~debevec/ and
http://fiatlux.berkeley.edu/.
About the speaker:
Paul Debevec studied math and computer engineering at the University of Michigan and received his Ph.D. in computer science from UC Berkeley where he is now a research scientist. While helping develop computer graphics technology, he has also collaborated with leading media artists to apply such technology to creative applications. He has directed several internationally exhibited computer animations, many of which have premiered at the SIGGRAPH Electronic Theater. His current work involves applying new image-based graphics techniques to interactive virtual environments, digital filmmaking, and cultural heritage. preservation.
Contact information:
Paul Debevec
Computer Science Division
University of California at Berkeley
Berkeley, CA
510-642-9940
510-642-5775
debevec@cs.berkeley.edu