X树非平衡保护多描述编码  

X-Tree Unequal Protected Multiple Description Coding

作　　者：陈婧[1] 蔡灿辉[1] 丁润涛[2] 

机构地区：[1]华侨大学信息科学与工程学院,泉州362021 [2]天津大学电子信息工程学院,天津300072

出　　处：《电子与信息学报》2005年第12期1973-1977,共5页Journal of Electronics & Information Technology

基　　金：国家自然科学基金(60472106)福建省自然科学基金(A0410018)资助课题

摘　　要：本文提出了一种新的多描述图像编码方案——X树非平衡保护多描述子带编码。首先把小波变换图像分解为结构信息和残余非零系数。其中结构信息包括非零系数的位置、符号和位数，是小波变换图像的关键信息，必须复制到每个描述。残余非零系数则通过多描述标量量化器生成两个索引分别放入不同的描述。两个描述通过不同的信道进行传输。由于每个描述都包含了图像的重要信息，因此，接收到一个信道的信息就可以重建出一定质量的图像。如果所有的信道传输的信息都被接收，就会得到比任何一个单独信道更好的重建图像。实验结果验证了本算法的有效性和正确性。A new Multiple Description Coding （MDC） scheme, X-tree based unequal protected MDC subband coding is proposed in this paper. The information of the wavelet transformed image is decomposed into two parts, the structure information and residues of significant coefficients. The structure information, including positions, signs and bit lengths of significant coefficients, is crucial and should be duplicated into both descriptions. The residues are mapped into couples of indices by a multiple description scalar quantizers, and sent to separate descriptions. Two descriptions are dispatched from different channels. Because every description includes all critical information of the picture, the reconstructed image from any single channel can have acceptable fidelity. The reconstructed image is of much better quality if both channels are available. Simulation results have verified the performance of the proposed algorithm.

关 键 词：多描述编码 子带编码 错误恢复 x树编码 非平衡保护 

分 类 号：TN919.8[电子电信—通信与信息系统]