Fast motion estimation and motion segmentation using multi-scale approach

The paper investigates a fast method for motion estimation and motion segmentation. We choose to decompose the motion on basis functions. That allows us to compute the velocity of each pixel by only solving a linear system. The motion segmentation is carried out using a Markovian formulation. We minimize the associated energy by a determinist algorithm. However, these choices induce two drawbacks: a temporal aliasing problem; a sensitivity of the optimization algorithm with the initialization. To overcome these two problems, we use a multiresolution method that successively computes the motion and the segmentation at each scale by motion compensation. Thanks to this procedure, we obtain a fast method of motion estimation and segmentation which does not require either initial spacial segmentation or dominant motion in the sequence.