Move the mouse cursor around over the image (which may take a
little while to appear).
This demo is based on the following paper: "What is the Set of Images
of an Object Under All Possible Lighting Conditions?", by
P. N. Belhumeur and D. J. Kriegman, in the proceedings of the 1996
conference on Computer Vision and Pattern Recognition (CVPR '96), page
Source code for the viewer is available, as
are the normal vectors.