【摘要】 为提高图像在噪声信道中传输的可靠性,该文提出了一种图像联合信源信道解码方案。信源图像首先经离散小波变换,压缩编码。编码数据经RCPC(率兼容删余卷积码)信道编码保护,通过噪声信道传输。在接收端的改进的APRI-SOVA(先验信息软输出维特比算法)在信道解码时,不仅利用了信道输出的软判决,而且进一步利用了信源解码器提供的当前解码的比特的可靠性信息。仿真结果显示,有效利用信源数据中遗留的相关性,能够实现图像解码质量的提高。更多还原

【Abstract】 A joint source-channel decoding approach is developed to improve the reliability of image transmissions.The source coders used is the discrete wavelet transform coding,and channel coders used is the RCPC(Rate-Compatible Punctured Convolutional) coding.At the receiver,after transmitted through noise channel,a modified APRI-SOVA(a Priori Soft-Output Viterbi Algorithm) is employed which using not only soft output of the channel but reliability of the current bit providing by source decoder.The simulation results show that the approach may be better to exploit the correlation remain in the source data and use it at the receiver side in order to achieve a more reliable decoding.更多还原