By reconstructing the illumination distribution of a scene, we can project realistic virtual shadows of a virtual object onto the real scene.
described a method to recover an illumination distribution of a scene from image brightness inside shadows cast by an object of a known shape .
The obtained illumination distribution is used to generate natural rendering images with multiple smooth shadows.
For seamless integration of a synthetic object within the image, the proposed method estimates the illumination distribution surrounding the virtual object and generates virtual shadows for AR application.
In general, image brightness inside shadows has a great potential for providing distant clues to the environmental illumination distribution.
Illumination distribution of the scene is represented with a set of point sources equally distributed on the geodesic dome.
Virtual shadows are rendered with the illumination distribution estimated from real scene.
In the second method, illumination distribution of the scene is represented with a set of point sources equally distributed on the geodesic dome.
Because Sato's method based on point sampling is sensitive to the number of sampling points and their positions, this method sometimes failed to provide a correct estimate of illumination distribution.
This paper presents two methods to estimate environment illumination distribution of a scene.
The elements are fully optimizable; for example, users can automatically optimize a CPC's size and angle to match a target illumination distribution
, intensity, total power or flux on a receiver.