摘要：为了适应不可靠网络传输对编码抗干扰能力的要求，提出了一种基于分层结构的多描述编码方案，该方案根据质量可分级的编码思想将小波系数分为两个描述，独立传输。其每个描述均包含基本层和增强层两部分信息。基本层由系数的关键信息组成，可拷贝到两个描述中同时传输，而增强层是系数的剩余信息，可拆分成两个部分通过不同描述传输。由于每个描述均包含可以恢复图像基本质量的关键信息，因此即使在丢失一个描述的情况下也可以保证较高的图像重建质量。实验结果表明，该方案是正确的和有效的，其在保证较高编码效率的同时，还能提高编码的抗干扰能力。

Abstract：A novel multiple description coding framework, called layered based multiple description coding(LBMDC), is proposed in this paper to meet the requirement of unreliable network transmission. The two-description coding scheme is proposed from SNR scalable layer coding, each description has a base layer and an enhancement layer. The base layer is composed of key information of coefficients and duplicated into both descriptions. The enhancement layer is the rest part of coefficients and split into two parts then sent to separate descriptions, respectively. Thus, the key information of the image is well protected. Even in the condition that one of descriptions is lost, the quality of restructured image is still good. Experimental results have verified the performance of the proposed MDC framework, which improves the ability of error resilient as well as the coding efficiency.