Light source estimation from a single image

One of the most difficult problems in Augmented Reality is how to ensure that the luminance of virtual objects embedded in a real scene is consistent with the real luminance. This paper shows an approach to identifying the illumination information from a single image of a real scene. Based on the assumption that the object used as a light probe has a globally convex shape, we can employ it to determine the illumination information in terms of the direction and the intensity.