Image Invariants for Smooth Reflective Surfaces

Image invariants are those properties of the images of an object that remain unchanged with change in camera parameters, illumination etc. In this paper, we derive an image invariant for smooth surfaces with mirror-like reflectance. Since, such surfaces do not have an appearance of their own but rather distort the appearance of the surrounding environment, the applicability of geometric invariants is limited. We show that for such smooth mirror-like surfaces, the image gradient exhibit degeneracy at the surface points that are parabolic. We leverage this result in order to derive a photometric invariant that is associated with parabolic curvature points. Further, we show that these invariant curves can be effectively extracted from just a few images of the object in uncontrolled, uncalibrated environments without the need for any apriori information about the surface shape. Since these parabolic curves are a geometric property of the surface, they can then be used as features for a va...

• Type: Conference
• Year: 2010
• Where: ECCV
• Keywords: Computer Vision, ECCV 2010, Image Invariant, Mirror-like Surfaces, Mitsubishi Electric Research