Study Of Inter Frame Coding In H.264/AVC

Inter prediction plays an important role in video coding due to its great capability of reducing temporal redundancy. In this paper, we propose three advanced technologies for inter frame coding based on template matching prediction.First, we propose a predictive patch matching for inter prediction. Besides the surrounding reconstructed pixels which form the template in template matching prediction, our proposed patch matching is able to utilize the predicted pixels generated by the traditional motion prediction. A linear combination of the reconstructed template and the predicted pixels permits to synthesize a prediction while maintaining the local variations of the target block. Furthermore, a mode selection mechanism is introduced to adaptively select the predictive patch matching at sub-block level. Experimental results demonstrate the effectiveness of our proposed predictive patch matching.In the second proposed technology, we further improve this predictive patch matching by incorporating line-based predictive patch matching with the previous block-based coding scheme, which we call hybrid predictive patch matching. Line-based structure is able to utilize both spatial and temporal correlations more efficiently than block-based structure with respect to different motion areas. The proposed hybrid prediction contributes to a reasonable mode decision selected explicitly at macroblock level depending on macroblock partition. Experimental results show the proposed scheme can reduce the bitrate compared to KTA.Finally, we propose a new motion compensated prediction scheme by adaptive patch matching with the full use of the reconstructed pixels surrounding the current block aiming at achieving a more accurate prediction than conventional MCP. The proposed scheme not only takes advantage of the temporal correlation but also efficiently exploits the spatial correlation between the current block and its template inside the patch. An adaptive linear combination of the current block and its template in motion estimation is designed to generate an optimal prediction while maintaining the local variation of the current block. Accordingly, a modification of the rate-distortion criterion is introduced to select the combined prediction. Experimental results show that our proposed APM achieves improved coding performance compared with H.264/AVC.