Abstract
In this paper, we present a new approach to simulate the daylight from sunrise to sunset based on a small set of photographs or CG generated images. The coherence character among image sequence at different times of day is employed, and each image under different illumination is thought to be expressed by two kinds of informations: common information and individual information. The color correction technique used in colorimetric is borrowed in this paper to relate color appearance from source image to color appearance under new illumination. A small set of photographs or CG synthesized images at different times of day are used as refernce images. From the reference images, a light-independent image, a shadow database and a color correction matrix database are constructed. Then new image at arbitrary time of day can be re-rendered quickly by executing shadow synthesis and color correction operation. Our result shows the daylight from sunrise to sunset can be simulated quickly without sacrificing the realism.
