Abstract:

A reflectance field describes the light transport through a scene in terms of incident and radiant illumination. Full knowledge of a scene's reflectance field allows to view this scene from any viewpoint and under any illumination condition. This simple yet powerful formulation is the basis for many image-based methods, and is the main focus of my research. My research can be categorized into three main topics: acquisition, compression and transfer of reflectance fields. For each of these research topics, a selected contribution is discussed in detail. The first presented contribution describes an acquisition method that enables to capture detailed reflectance fields for image-based relighting using non-adaptive illumination (i.e., measurement) patterns. These measurement patterns are incoherent with the reflectance field itself, and the number of measurement patterns is proportional to the size of the compressed field, rather than the size of full uncompressed field. The second discussed contribution details a novel compression method for (measured) heterogeneous subsurface scattering, i.e., the way light scatters through a non-homogeneous semi-opaque medium. This compression is based on a specially developed matrix factorization method. A third contribution, demonstrates a post-production method that successfully generates plausible relit sequences of dynamic facial performances of a subject. Relighting is achieved by transferring reflectance information from a single reflectance field of a static pose of a potentially different subject, but similar in appearance. In the final part of this presentation, an overview of short term and long term research plans are given. Additionally, some preliminary results of recent research are shown.