航空学报 > 2002, Vol. 23 Issue (6): 534-537

基于可逆提升小波变换和上下文预测的SAR图像无损压缩算法

刘荣科, 张晓林, 廖小涛, 聂振钢   

  1. 北京航空航天大学电子工程系 北京 100083
  • 收稿日期:2001-10-11 修回日期:2002-08-01 出版日期:2002-12-25 发布日期:2002-12-25

LOSSLESS IMAGE CODING ALGORITHM FOR SAR BASED ON REVERSIBLE LIFT SCHEMATICS COMBINED WITH CONTEXT PREDICTOR

LIU Rong-ke,ZHANG Xiao-lin,LIAO Xiao-tao,NIE-Zhen-gang   

  1. Department of Electronic Engineering, Beijing University of Aeronautics and Astronautics, Beijing 100083, China
  • Received:2001-10-11 Revised:2002-08-01 Online:2002-12-25 Published:2002-12-25

摘要:

结合可逆提升小波变换和上下文预测技术 ,提出基于可逆提升小波变换和上下文预测的合成孔径雷达 (SAR)图像的无损压缩算法。分析了基于提升小波的无损压缩算法和基于上下文预测编码的无损压缩算法的优缺点 ,联合两种体制 ,提出先用提升小波变换去除整幅图像的冗余 ,再用边缘保留预测器和子预测器联合技术进一步消除子带内系数间的空间冗余性 ,最后采用自适应上下文建模技术对残差进行分类自适应熵编码。除具有常规小波变换编码的优异性能外 ,该算法的压缩率优于即将推出的国际标准JPEG2000。

关键词: 合成孔径雷达, 提升方案, 小波变换, 预测编码, 无损压缩

Abstract:

A lossless image coding algorithm for SAR was proposed, which adopts the reversible lift schematics combined with the context predictor. The reversible lift schematics can efficiently reduce redundant in the SAR image and the context predictor has excellent adaptive edge prediction and smooth prediction abilities. The adaptive context modeling mostly improves the entropy coding ratio. The algorithm has a higher compression ratio than the lossless part in the incoming ISO standard JPEG2000, besides the normal virtue of wavelet coding.

Key words: SAR, lift schematics, wavelet transform, prediction coding, lossless image coding