Madsen, Claus B.Sorensen, Mads K. D.Vittrup, Michael2015-11-122015-11-1220031017-4656https://doi.org/10.2312/egs.20031065Image-based lighting (IBL) of virtual objects has become a popular approach to blending virtual and real scenes. In IBL an omni-directional image of a scene is used as the illumination environment for rendering virtual objects. Typically, this rendering is based on global illumination techniques which are far from capable of real-time performance. In this paper we describe how to estimate the positions and radiances of a small number of point light sources, e.g., on the order of 5 to 10, which will produce virtual object appearances which are consistent with those obtained using IBL. The estimated light source parameters can be used directly in OpenGL rendering for real-time performance. We demonstrate the approach on natural scenes.10.2312/egs.20031065