该文提出一种适用于丢包信道的基于小波变换的可伸缩图像编码传输方案。该方案利用分层多描述编码来提高信源编码的容错性能,利用信道编码来提高系统整体的抗丢包性能,采用编码后率失真优化技术对信源编码进行优化。利用非系统的RS码对信源编码符号和信道编码符号进行重新排序,将分层多描述编码和信道编码进行了有效的结合。通过在编解码端采用相同的排序算法,来减少传输开销。仿真结果表明,该方案与现有的方案相比,提高了接收图像的质量,并且需要较少的传输开销。
A scheme is proposed for transmission of wavelet-based progressive image coding over packet erasure channel. The scheme uses layered multiple description coding to improve the error resilience performance of the source coding, and uses channel coding to combat the packet erasure. Post Compression Rate Distortion optimization (PCRD-opt) technique is adopted to optimize source coding. By reordering the source coding symbols and channel coding symbols through permuted systematic RS codes, the layered multiple description coding and channel code are combined efficiently. The same sorting algorithm is adopted at encoder and decoder to reduce the overhead. Experimental results show that the proposed scheme improves the received image quality with less overhead compared to the existing method.