中文摘要：

提出了一种面向空间通信不平等差错保护的联合信源信道编解码方法．该方法采用一种可逆编解码方法对直流系数进行重点保护，即对直流系数编码输出码流进行二进制游程编码，并采用可逆变长码对游程长度进行编码．对重要性较低的交流（AC）系数采用可变长编解码．仿真实验结果和分析表明，该方法有效地解决了错误扩散，提高了直流系数的抗差错性能，改善了图像传输质量．

英文摘要：

In this paper we proposed a joint source-channel coding/decoding approach based on unequal error protection in space communication since the DC coefficients are especially significant for image quality in CCSDS IDC. A reversible coding/decoding scheme was adopted for the DC coefficients for special protection, in which the output bit stream of the DC coefficients was encoded by using alternating run-length encoding and then the runlengths were encoded by reversible variable length codes （RVLC）. Meanwhile, variable length coding/decoding scheme was adopted for the AC coefficients. The experiment showed that this approach could greatly alleviate error propagation and improve the error-resilient performance of the DC coefficients, and the approach thereby could improve transmitted image quality.