An affine motion compensation framework for high efficiency video coding

As the translational motion model used in recent video coding standards cannot represent the complex motion such as rotation and zooming well, a simple local affine motion compensation framework supporting multiple reference frames is proposed in this paper to characterize the complex motion. Besides, since the commonly used fast motion estimation for affine motion model is still quite complex, a fast gradient based affine motion estimation algorithm is proposed to decrease the encoder complexity. The proposed algorithm is implemented into the test model of the newest video coding standard High Efficiency Video Coding (HEVC). Experimental results show that the bit rate reduction for sequences with complex motion can be up to 16.8%.