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在无线移动信道和因特网等环境下的压缩视频传输业务，信道传输差错不但严重影响业务质量，甚至会导致整个视频通信完全失效。采用变长编码时，变长编码虽然提高了编码效率，但也使得编码后的视频数据对抗差错的能力十分脆弱。而采用可逆变长编码可以对码流进行双向解码，在差错发生后，解码器可分别由两个重同步点进行解码，并可更精确地确定差错发生的位置，恢复部分本应丢弃的数据。文章将可逆变长编码差错复原技术应用在数字视频传输中，采用可逆变长编码，对应用了数据分割技术的压缩视频传输码流中的宏块头信息和运动矢量等重要信息进行编码，从而提高视频流的抗差错能力和解码端的差错复原能力。并利用第三代移动通信系统的信道模型进行了差错复原技术的实验。结果表明，在应用了可逆变长编码差错复原技术后，重建图像的主客观质量得到了明显的改善。
In compressed video transmission services such as wireless mobile channels and the Internet, channel transmission errors not only seriously affect the quality of services, but also completely invalidate the entire video communication. Variable-length coding, variable-length coding, while improving the coding efficiency, but also makes the encoded video data is very vulnerable to the ability to combat errors. The use of reversible variable-length coding can bidirectionally decode the code stream. After the error occurs, the decoder can decode each of the two resynchronization points, and can more accurately determine the location of the error, restore part of the discarded data. In this paper, reversible variable length coding error recovery technology is applied to digital video transmission. By using reversible variable length coding, important information such as macroblock header information and motion vector in the compressed video transmission code stream applying data segmentation is coded, Thereby improving the video stream error resilience and decoding end of the error recovery capability. And the third generation mobile communication system channel model error recovery technology experiments. The results show that the subjective and objective quality of the reconstructed image has been significantly improved after the application of the reversible variable length coding error recovery technology.