Estimation of Multiple Directional Light Sources for Synthesis of Mixed Reality Images

We present a new method for the detection and estimation of multiple directional illuminants, using a single image of any object with known geometry and Lambertian reflectance. We use the resulting highly accurate estimates to modify virtually the illumination and geometry of a real scene and produce correctly illuminated Mixed Reality images. Our method obviates the need to modify the imaged scene by inserting calibration objects of any particular geometry, relying instead on partial knowledge of the geometry of the scene. Thus, the recovered multiple illuminants can be used both for image-based rendering and for shape reconstruction. Our method combines information both from the shading of the object and from shadows cast on the scene by the object. Initially we use a method based on shadows and a method based on shading independently. The shadow based method utilizes brightness variation inside the shadows cast by the object, whereas the shading based method utilizes brightness va...

• Type: Conference
• Year: 2002
• Where: PG
• Authors: Yang Wang, Dimitris Samaras
• Keywords: Computer Graphics, Method Combines Information, Method Utilizes Brightness, Multiple Directional Illuminants, PG 2002