Accurate Light Source Acquisition and Rendering

Figure 1: Stages of light source measurement and rendering (from left to right): a) photo of flashlight – b) flashlight in measurement setup – c) 2D reconstruction of the measured data in a virtual plane – d) measured light used in a global illumination simulation. Realistic image synthesis requires both complex and realistic mod-els of real-world light sources and efficient rendering algorithms to deal with them. In this paper, we describe a processing pipeline for dealing with complex light sources from acquisition to global illu-mination rendering. We carefully design optical filters to guarantee high precision measurements of real-world light sources. We dis-cuss two practically feasible setups that allow us to measure light sources with different characteristics. Finally, we introduce an effi-cient importance sampling algorithm for our representation that can be used, for example, in conjunction with Photon Maps