<title>Iterative motion estimation method using triangular patches for motion compensation</title>

Abstract

In order to overcome the drawback of the conventional block-based motion compensation, a new triangle-based method which utilizes triangular patches instead of blocks has recently been proposed. Compared to conventional methods which represent the motion of scene objects by translational displacements of blocks, the new method can cope with a wider range of motions since it allows for rotation and deformation of the triangular patches. In the block-based motion compensation, a simple local minimization algorithm (i.e. block matching) is applied to obtain the displacement vector of each block. However it is inappropriate to apply this algorithm in the triangle-based motion compensation because of the complicated linkage between the deformation of the triangular patches and the displacements of the grid points (vertices of triangles). Consequently, the primary issue is to find an optimal way to estimate motion of the grid points. In this paper, we present a new motion estimation algorithm called hexagonal matching which iteratively refines the estimated displacement vectors. Simulation results show that the motion estimation algorithm produces less prediction error than the previously proposed triangle-based method or the block-based method. We also propose another algorithm with similar function but less computational complexity.