Center for Signal and Image Processing, School of Electrical and Computer Engineering, Georgia Institute of Technology, Atlanta, GA30332-0250, USA.
IEEE Trans Image Process. 2002;11(11):1314-31. doi: 10.1109/TIP.2002.804275.
Compressed video sequences are very vulnerable to channel disturbances when they are transmitted through an unreliable medium such as a wireless channel. Transmission errors not only corrupt the current decoded frame, but they may also propagate to succeeding frames. A number of post-processing error concealment (ECN) methods that exploit the spatial and/or temporal redundancy in the video signal have been proposed to combat channel disturbances. Although these approaches can effectively conceal lost or erroneous macroblocks (MBs), all of them only consider spatial and/or temporal correlation in a single frame (the corrupted one), which limits their ability to obtain an optimal recovery. Since the error propagates to the next few motion-compensated frames in the presence of lost MBs in an I or P frame, error concealment should simultaneously minimize the errors not only in the current decoded frame but also in the succeeding B and P frames that depend on the corrupted frame. We propose a novel multiframe recovery principle which analyzes the propagation of a lost MB into succeeding frames. Then, MPEG-compatible spatial and temporal error concealment approaches using this multiframe recovery principle are proposed, where the lost MBs are recovered in such a way that the error propagation is minimized.
当压缩的视频序列通过不可靠的媒介（如无线信道）传输时，它们非常容易受到信道干扰的影响。传输错误不仅会破坏当前解码的帧，还可能传播到后续的帧。已经提出了许多利用视频信号中的空间和/或时间冗余的后处理错误隐藏（ECN）方法来对抗信道干扰。虽然这些方法可以有效地隐藏丢失或错误的宏块（MB），但它们都只考虑了单个帧（被污染的帧）中的空间和/或时间相关性，这限制了它们获得最佳恢复的能力。由于在 I 帧或 P 帧中存在丢失的 MB 时，错误会传播到下几个运动补偿帧中，因此错误隐藏应该同时最小化不仅当前解码帧而且还依赖于被污染帧的后续 B 和 P 帧中的错误。我们提出了一种新的多帧恢复原理，该原理分析了丢失的 MB 传播到后续帧的情况。然后，提出了使用这种多帧恢复原理的 MPEG 兼容的空间和时间错误隐藏方法，其中以最小化错误传播的方式恢复丢失的 MB。
