The information available to a moving observer from specularities

摘要

This paper examines the information available from the motion of specularities (highlights) due to known movements by the viewer. In particular two new results are presented. First, it is shown that for local viewer movements the concave/convex surface ambiguity can be resolved without knowledge of the light source position. Second, the authors investigate what further geometrical information is obtained under extended viewer movements, from tracked motion of a specularity. The reflecting surface is shown to be constrained to coincide with a certain curve. However, there is some ambiguity — the curve is a member of a one-parameter family. Fixing one point uniquely determines the curve.