<title>Adaptive overlapped block motion compensation</title>

Abstract

An adaptive overlapped block motion compensation (OBMC) scheme, which takes the rate, distortion and complexity factors into account, is proposed in this research. With this scheme, the encoder uses the classification information to determine which blocks could be distorted after OBMC. Then, the BMC search rather than the OBMC search is applied to these blocks. Depending on the allowed computational complexity of the decoder, the encoder chooses the best set of OBMC macroblocks which requires a higher complexity. Other macroblocks simply adopt BMC. Furthermore, the motion bit rat can be reduced by soothing the motion field of BMC blocks during motion search in the encoder. An effective group OBMC motion search scheme is applied to this new adaptive OBMC motion scheme. Experimental results show that the complexity of both the encoder and the decoder is reduced while the visual quality remains the same due to ten improvement in the oversmooth region.