  We introduce a visual motion segmentation method employing spherical geometry
for fisheye cameras and automoated driving. Three commonly used geometric
constraints in pin-hole imagery (the positive height, positive depth and
epipolar constraints) are reformulated to spherical coordinates, making them
invariant to specific camera configurations as long as the camera calibration
is known. A fourth constraint, known as the anti-parallel constraint, is added
to resolve motion-parallax ambiguity, to support the detection of moving
objects undergoing parallel or near-parallel motion with respect to the host
vehicle. A final constraint constraint is described, known as the spherical
three-view constraint, is described though not employed in our proposed
algorithm. Results are presented and analyzed that demonstrate that the
proposal is an effective motion segmentation approach for direct employment on
fisheye imagery.
