Singularities of Illuminated Surfaces

Abstract

We study local singularities that appear in pictures of illuminated objects: we suppose there is only one light source and we look at the shadow it casts on the surface. We focus on the frontier between shadow and light. In the visual plane, these curves interact with the apparent contour of the surface. The search of generic situations translates into a classification problem in singularity theory. We are thus able to give the list of the six stable and generic views of illuminated surfaces.