Illuminant retrieval for fixed location cameras

Fixed location cameras, such as panoramic cameras or surveillance cameras, are very common. In images taken with these cameras, there will be changes in lighting and dynamic image content, but there will also be constant objects in the background. We propose to solve for color constancy in this framework. We use a set of images to recover the scenes’ illuminants using only a few surfaces present in the scene. Our method retrieves the illuminant in every image by minimizing the difference between the reflectance spectra of the redundant elements’ surfaces or, more precisely, between their corresponding sensor response values. It is assumed that these spectra are constant across images taken under different illuminants. We also recover an estimate of the reflectance spectra of the selected elements. Experiments on synthetic and real images validate our method.