Overlapped block motion compensation based on irregular grid

In this work, we propose a hybrid motion compensation integrating the advantages of control grid interpolation (CGI) and overlapped block motion compensation (OBMC). We consider control points of CGI and overlapped window of OBMC as sampling points and spread function of motion vector, respectively. Then, a whole motion field in a frame is composed of motion vectors on sampling points and their spreadings. In this view-point, the conventional OBMC is considered as regular grid based OBMC (RG-OBMC) while the proposed OBMC is called irregular grid based OBMC (IG-OBMC). Experimental results demonstrate that the proposed IG-OBMC achieves improved visual quality as well as better PSNR performance than conventional motion compensation methods.