面向码通并行的JPEG2000实时码流控制算法  

Real-time rate control algorithm for pass-parallel based JPEG2000

作　　者：秦兴[1] 刘纯悦[1] 严晓浪[1] 

机构地区：[1]浙江大学超大规模集成电路设计研究所,浙江杭州310027

出　　处：《浙江大学学报（工学版）》2006年第6期1071-1075,共5页Journal of Zhejiang University：Engineering Science

基　　金：国家"863"高技术研究发展计划资助项目(2003AA1Z10060)

摘　　要：为了提升基于码通并行的熵编码速度,提出了一种新的实时码流控制算法.该算法采用基于码通失真权重的失真模型估计失真,并行地调整三码通斜率,将斜率调整后的预备截断码通信息存储在查找表1中,并将预备截断点在表1中的首地址和最后一个截断码通相对于该地址的偏移量存储在查找表2中,通过更新和搜索两张查找表,动态地生成斜率门闸.实验结果表明,该算法节省了存储面积,减少了存储器访问次数,降低了计算复杂度.与JPEG2000评估软件模型相比,使用该算法重构的图像质量只下降了大约0.3 dB,在低比特图像压缩情况下,码通并行的熵编码执行时间可减少50%以上.To significantly speed up the pass-parallel based entropy coding, a novel real-time rate control algorithm was proposed. The distortion was estimated by the model based on the pass-distortion weight, and three pass slopes were modified simultaneously in the algorithm. The information on the candidate truncation pass was stored in the first lookup table. The first address where the candidate truncation pass was stored in the first lookup table and the offset of the last truncation pass relative to the address was stored in the second lookup table. The slope threshold was generated dynamically through refreshing and searching of the two lookup-tables. Experimental results show that the algorithm saves the storage areay and reduces the access times of memory and the computation complexity. Compared with the results of JPEG2000 verification software model, the reconstructed image quality only drops about 0.3 dB, and above 50 % executive time of pass-parallel based entropy coding can be decreased by the algorithm for low bit rate image compression.

关 键 词：码通并行 JPEG2000 实时码流控制 

分 类 号：TP242.6[自动化与计算机技术—检测技术与自动化装置]