Fast direct methods for computing optical flow along contours

Iterative methods, such as the conjugate gradient method, have long been used for the computation of optical flow along contours. For a contour with N points, the conjugate gradient method requires O(N) iterations (i.e., O(N²) operations) to converge to a solution. We propose direct analytical methods for computing optical flow along both open contours and closed contours. These methods use O(N) operations, are numerically stable, and can be easily implemented on parallel hardware