Ambient Light Transfer

In the following work we present a system for capturing ambient light in a real scene and recreating it in a room equipped with computer-controlled lamps. We capture incident light in one point of a scene with a simple light probe consisting of a camera and a reflective sphere. The acquired environment map is then transferred to a room where an approximated lighting condition is recreated with multiple LED lamps. To achieve this, we first measure the impact each lamp has on the illumination with a light probe and acquire one image per lamp. A linear combination of these images produces a new environment map, which we can recreate inside the room by setting the intensities of the lamps. We employ Quadratic Programming to find the linear combination that approximates a given environment map best. We speed up the optimization process by downsampling the light probe data, which reduces the dimension of our problem. Our method is fast enough for real-time light transfer and works with all types of linear controlled illuminants. In order to evaluate our method, we designed and constructed an omnidirectional lighting system that can spatially illuminate a room in full-color. We first explore several different configurations of our lighting system, our sampling and our optimization algorithm. We then demonstrate our method’s capabilities by capturing static and dynamic ambient light in one location and transferring it into a room. 0.2 Kurzfassung In der folgenden Arbeit stellen wir ein System vor mit dem man das Umgebungslicht a