In this paper the problem of optical flow and occlusion mask estimation is aborded. To that end, we consider a multi-label representation of the optical flow and we define an energy that models the problem. The convexification of the energy and its minimization with an iterative algorithm are studied. Our algorithm is implemented in GPU, since each pixel can be processed in parallel. From our experiments, the relation between the quality of the results obtained and computing time seems to be very promising.