Higher order polynomials, free form deformations and optical flow estimation

In this paper, we propose a novel technique to represent and recover optical flow through free form deformations. Such a technique is based on representing the motion field using regular connected grids according to higher order polynomials, a compromise between dense motion estimation and parametric motion models. Optical flow is determined through the deformation of the grid - derived from the optimization of a cost function - and consequently of the underlying image structures towards satisfying the constant brightness constraint. Smoothness conditions are implicitly accounted for through the free form deformation approach. Promising results demonstrate the potentials of our approach.