The image irradiance of a three-dimensional object is known to be the function of three components: the distribution of light sources, the shape, and reflectance of a real object surface. In the past, recovering the shape and reflectance of an object surface from the recorded image brightness has been intensively investigated. On the other hand, there has been little progress in recovering illu...

The following being musings about illumination problems and illumination answers, more particularly about the evolution and the interplay between local and global illumination concerns.

The goal in global illumination solutions for dynamic environments is to update a scene based on past scenes. Current state of the art solutions are either not applicable, or unduly complex, when there are large changes in the illumination of unbounded number of objects. Such changes may be caused by the appearance of unexpected (at modeling time), irregular light sources. We define a subset of...

We present a new method to segment images of structured surfaces from illumination series, i.e. sets of images of an object recorded with different lighting settings. We use a parallel light source whose angle of incidence is described by the azimuth and the elevation angle. Depending on the surface topography, characteristic patterns are described by the intensities viewed by the camera depend...

This paper uses theory, simulation, and laboratory experiment, to show that directional illumination, used during the image acquisition process, acts as a directional filter of three dimensional texture. It is shown that the directional characteristics of image texture are not intrinsic to the physical texture being imaged, as they are affected by the direction of the illumination. This result ...

Natural images are the composite consequence of multiple factors related to scene structure, illumination, and imaging. For facial images, the factors include different facial geometries, expressions, head poses, and lighting conditions. We apply multilinear algebra, the algebra of higherorder tensors, to obtain a parsimonious representation of facial image ensembles which separates these facto...