基于块运动变形的时域差错掩盖  

Temporal Error Concealment Based on Block-warping

作　　者：杨天武[1] 彭强[1] 诸昌钤[1] 

机构地区：[1]西南交通大学信息科学与技术学院,四川成都610031

出　　处：《小型微型计算机系统》2007年第1期155-158,共4页Journal of Chinese Computer Systems

基　　金：国家自然科学基金项目(60672099)资助;铁道部科技研究开发项目(2003X040-A)资助;西南交通大学科学基金项目(2002A04)资助.

摘　　要：传统的时域差错掩盖技术通常将宏块作为整体考虑,没有具体分析受损宏块的运动特征,当受损宏块具有复杂剧烈的运动时掩盖效果不理想.通过对受损宏块的运动特征认真研究,提出了基于块变形的时域差错掩盖算法.算法充分利用受损宏块的周围信息将宏块运动划分成多种运动情况,针对不同运动情况采取不同的掩盖策略.在确定某受损块存在块变形运动时实施块变形掩盖,并通过合理的变形区域选择保证块变形的合理性.基于H.263+的GOB交织打包仿真实验表明,提出算法对存在复杂剧烈运动的宏块掩盖效果良好,与BM和MFI-BM掩盖相比,掩盖后的主客观视频质量有显著的改善.Traditional temporal concealment techniques often simply treat the marcoblock （MB） as a whole part without any results to detailed analysis of motion characteristic of the damaged MB and any corresponding concealment strategy to this motion. That inevitably results to poor concealment performance for damaged MB, especially for those with intense and complicated motion. After the studies of the motion characteristic of the damaged MB, a novel temporal error concealment algorithm based on block warping techniques is proposed. In this algorithm, the motion of damaged MB is firstly divided into many motion cases by utilizing information of its surrounding MBs, and then different concealment methods are used to meet different motion cases. The block-warping concealment is taken once the block-warping motion of block is detected. Furthermore, the rationality of the block-warping method can be firmly ensured a by reasonable choice of the block-warping cases. Simulation resuits based on H. 263＋ codec and interlaced GOBs techniques show its satisfactory concealment performance, especially for the damaged blocks with intense and complicated motion. Compared with the popular BM and MFI-BM concealments, the subjective and objective video quality of our concealment is remarkably improved.

关 键 词：差错掩盖 视频传输 差错恢复 H.263+ 

分 类 号：TN919.8[电子电信—通信与信息系统]