一种基于场一致性的H.264整帧丢失掩盖方法

摘要

In this paper, an error concealment method is proposed to deal with frame losses happened in H.264 video transmission, which could be used in B and P frames. For P frames, this method needs to alter the decoding work flow to obtain information from one succeeding frame. After reference Motion Vector (MV) list is obtained by MV extrapolation, a field coherence based algorithm is used to select the best MV from the two neighboring frames in order to achieve the reconstruct MV. For B frames, the field coherence based algorithm is used to obtain the reconstruct MV from the succeeding P frame. Test results demonstrate that this method outperforms traditional methods both objectively and subjectively. The conclusion is that this method is efficient when dealing with frame loss cases in H.264 video transmission.%针对H.264视频序列在传输中可能发生的整帧丢失现象,提出了一种新型的整帧丢失掩盖算法,该算法可用于P帧和B帧.对于P帧,该算法需要修改解码器的解码流程,使得掩盖丢失帧时能获取后一帧的运动矢量信息.然后,利用运动矢量映射的方法获取重建丢失帧的参考运动矢量列表,采用基于场一致性的判决方式分别选取前一帧中和后一帧中的最佳运动矢量以取得最终重建矢量.对于B帧,利用后P帧的运动矢量信息,采用基于场一致性的判决方式得到最终重建矢量.实验结果说明此算法和传统的整帧掩盖算法相比能获得更高的PSNR,并且有更好的视觉显示效果.所提算法在H.264视频发生整帧丢失时有较好的掩盖效果.