Efficient recognition of rotationally symmetric surfaces and straight homogeneous generalized cylinders

It is known that rotationally symmetric surfaces can be recognized from their outlines alone, using cross-ratios of bitangent intersections. A successful implementation of this technique is demonstrated using a novel bitangent finder which works on images of real scenes. The stability of the cross-ratios is reported and compared to affine invariants. The recognition technique is shown to extend to the case of straight homogeneous generalized cylinders.