Kim Joohee, Mersereau Russell M, Altunbasak Yucel
Center for Signal and Image Processing, Georgia Institute of Technology, Atlanta, GA 30332-0250, USA.
IEEE Trans Image Process. 2004 Dec;13(12):1547-53. doi: 10.1109/tip.2004.837552.
This paper presents a coordinated multiple-substream unequal error-protection and error-concealment algorithm for SPIHT-coded bitstreams transmitted over lossy channels. In the proposed scheme, we divide the video sequence corresponding to a group of pictures into two subsequences and independently encode each subsequence using a three-dimensional SPIHT algorithm. We use two different partitioning schemes to generate the substreams, each of which offers some advantages under the appropriate channel condition. Each substream is protected by an FEC-based unequal error-protection algorithm, which assigns unequal forward error correction codes to each bit plane. Any information that is lost during the transmission for any substream is estimated at the receiver by using the correlation between the substreams and the smoothness of the video signal. Simulation results show that the proposed multiple-substream UEP algorithm is simple, fast, and robust in hostile network conditions, and that the proposed error-concealment algorithm can achieve 2-3-dB PSNR gain over the case when error concealment is not used at high packet-loss rates.
本文提出了一种针对在有损信道上传输的SPIHT编码比特流的协同多子流不等差错保护和差错掩盖算法。在所提出的方案中,我们将对应于一组图像的视频序列划分为两个子序列,并使用三维SPIHT算法独立地对每个子序列进行编码。我们使用两种不同的划分方案来生成子流,每种方案在适当的信道条件下都具有一些优势。每个子流由基于前向纠错(FEC)的不等差错保护算法进行保护,该算法为每个比特平面分配不等的前向纠错码。在接收端,利用子流之间的相关性和视频信号的平滑性来估计在传输过程中任何子流丢失的任何信息。仿真结果表明,所提出的多子流UEP算法在恶劣网络条件下简单、快速且稳健,并且所提出的差错掩盖算法在高丢包率情况下,相较于不使用差错掩盖的情况,能够实现2至3dB的峰值信噪比(PSNR)增益。