Stereo with oblique cameras

Mosaics acquired by pushbroom cameras, stereo panoramas, omnivergent mosaics, and spherical mosaics can be viewed as images taken by non-central cameras, i.e. cameras that project along rays that do not all intersect at one point. It has been shown that in order to reduce the correspondence search in mosaics to a one-parametric search along curves, the rays of the non-central cameras have to lie in double ruled epipolar surfaces. In this work, we introduce the oblique stereo geometry, which has nonintersecting double ruled epipolar surfaces. We analyze the configurations of mutually oblique rays that see every point in space. We call such configurations oblique cameras. We argue that oblique cameras are important because they are the most non-central cameras among all cameras. We show that oblique cameras, and the corresponding oblique stereo geometry, exist and give an example of a physically realizable oblique stereo geometry.