基于LDPC的码率自适应分布式视频编码  

Rate adaptive distributed video coding based on LDPC

作　　者：杨春玲[1] 夏洪涛[1,2] 张兴绍[1] 

机构地区：[1]华南理工大学电子与信息学院,广州510640 [2]中国联合网络通信有限公司广州分公司,广州510630

出　　处：《中国图象图形学报》2010年第12期1707-1713,共7页Journal of Image and Graphics

基　　金：国家自然科学基金项目(60972135);中央高校基本科研业务费专项资金项目(2009ZM0231);广东省自然科学基金项目(06025642)

摘　　要：为了在分布式视频编码(DVC)中取得更好的压缩性能,将校验节点的合并和分裂进行有机结合,提出了一种码率自适应LDPC(RALDPC)编码新方法。该方法首先基于PEG算法构造高压缩比LDPC码字;然后由行均匀分裂得到低压缩比码字;最后通过合并或分裂校验矩阵对应的行来适度调整码率。为保证码字性能,还提出了校验节点合并的3个限制条件,并基于RALDPC提出了一种码率自适应DVC编码方案。实验结果表明,与当前基于Turbo码的DVC方案相比,在原信息和边信息高度或中度相关时,编码性能提高了0.1～0.7 dB。In order to achieve better rate distortion （RD） performance in distributed video coding （DVC）, a new rate- adaptive low density parity check （RALDPC） coding algorithm is proposed. Firstly, a high compression ratio code is constructed based on progressive edge-growth （PEG） algorithm. Then low compression ratio codes are obtained using row splitting algorithm. The rate can be well adjusted by merging and splitting the parity-check matrix rows. And three restriction conditions for merging check nodes are proposed in order to obtain good performance codes. Based on the RALDPC, a rate adaptive DVC algorithm is proposed, which can achieve better RD performance about 0.1-0.TdB compared to DVC algorithm based on the popular Turbo codes, when the correlation between the original and side information is medium or high.

关 键 词：分布式视频编码 低密度奇偶校验(LDPC)码 码率自适应 PEG算法 校验式 

分 类 号：TN919.81[电子电信—通信与信息系统]