卫星干涉多光谱图像压缩新算法

根据卫星干涉多光谱图像的成像特性,提出一种基于分类权值率失真优化截取和自适应编码深度控制的部分SPIHT光谱图像压缩算法.首先根据干涉区域类型和编码平面的重要性,对各棵零树各个编码过程赋予不同的重要性权值,然后采用部分SPIHT算法对每棵零树独立编码,编码时根据比特平面层中重要系数的统计概率自适应地进行3种编码模式的选择,同时依据重要性权值和深度控制因子自适应地控制每棵零树的编码深度,最后在编码深度内,根据不同干涉区域的零树对恢复光谱的失真贡献,采用分类权值率失真方法对码流进行优化截取,使码流分配与失真达成最优.实验结果表明,本算法比传统算法更好地保护了光谱信息.

A Novel Algorithm for Satellite Interferential Multispectral Images Compression

Based on the analysis of the characteristic of the satellite interferential multispectral images, a new compression algorithm based on partial SPIHT with the classified weighted rate-distortion optimized truncation and adaptive coding depth control is proposed.The different significance weights are initially given to every coding passes in each zero tree, according to the classification of interferential regions and the significance of coding bitplanes.The zero trees are coded independently by Partial SPIHT,which selects adaptively one of three different coding modes relying on the probability of the significant coefficients in each bitplane,and determined the corresponding coding depth with significance weights and depth control factor.The classified weighted rate-distortion optimized truncation is applied within the coding depth,according to the distortion contribution to constructed spectrum of zero trees in different interferential regions.The experimental results show that the proposed algorithm improves the protection of spectral information over conventional algorithms,and efficiently reduces the computation complexity and memory usage.