Estimating optical flow using a global matching formulation and graduated optimization

In this paper we consider the problem of optimal optical flow estimation assuming brightness conservation and piecewise smoothness. We propose a formulation based on three-frame matching and global optimization allowing local variation. It is superior to popular gradient-based models and more justifiable than existing global methods. We also develop an efficient technique to minimize the resultant global energy. It takes advantage of local gradient, global gradient and global matching methods and overcomes their limitations. Experiments on various synthetic and real data and comparison with state-of-the-art techniques show that the method achieves discontinuity preserving capability and sub-pixel accuracy.