Multigrid computation of rotationally invariant non-linear optical flow

In supplement to an earlier paper, we present an altered cost functional for the computation of an edge-preserving optical flow that is invariant to rotation. In addition, we explain how the solutions to the resulting non-linear partial differential equations may be computed more efficiently with non-linear multigrid techniques. We prove the rotational invariance of this functional and report computation times on a real image sequence.