基于PSMSD的JPEG2000优化率控制算法

Efficient rate control algorithm for JPEG2000 based on PSMSD

对优先扫描率分配算法进行分析,提出了一种基于比特平面优先扫描和最小斜率丢弃的JPEG2000压缩率控制算法,以解决优先扫描率分配对重建图像质量带来的影响。对所有编码通道根据比特平面优先级从高到低依次进行T1编码,达到目标码率后对所有码块进行率失真最小斜率丢弃算法来完成优化截取,从而进一步快速搜索最优码流截取点,有效地降低了T1编码器的冗余。实验结果表明,该算法有效减少了计算量和存储量,且获得了与标准算法基本相同的高压缩性能。

After the elaborate analysis for the rate allocation algorithm based on priority scanning, a fast and efficient rate control algorithm for JPEG2000 based on priority scanning and minimal slope discarding is presented to eliminate influence of priority scanning rate allocation algorithm to the reconstructed image quality. The coding passes of all coding blocks are encoded by T1 encoder with bit-plane priority. After the accumulate bit-rate exceeds the target bit-rate, minimal slope discarding scheme is used for all blocks to complete the ratedistortion optimization truncation, which can more efficiently reduce the redundancy of T1. The experimental results show that the proposed scheme can efficiently reduce both the computational cost and working memory size of the entropy coding process, while obtaining almost the same performance as the conventional rate control algorithm in JPEG2000 standard.