风云二号气象卫星图像自动几何精校正  

Automatic geometric precision correction of Fengyun-2 meteorological satellite imagery

作　　者：杨磊[1,2] 冯小虎[1,2] 郭强[1,2] 陆风[1,2] 张晓虎[1,2] 

机构地区：[1]中国气象局中国遥感卫星辐射测量和定标重点开放实验室,北京100081 [2]中国气象局国家卫星气象中心,北京100081

出　　处：《计算机工程与应用》2011年第3期202-206,209,共6页Computer Engineering and Applications

基　　金：国家自然科学基金No.40975017;No.60702040;科技部科技支撑项目(No.2008BAC40B03);公益性行业(气象)科研专项(No.GYHY200806023)~~

摘　　要：介绍了一种风云二号(FY-2)卫星图像自动几何精校正系统和方法。首先获得标称图坐标系下的二值化地标模板,然后通过Bayes后验概率,获得二值化FY-2待匹配图像;通过最大相关系数方法将地标模板与FY-2标称图进行匹配,获得地标偏移量;再通过质量控制获得匹配成功的地标对,实现自动的地标匹配。最后,应用DLT变换对FY-2图像进行几何精校正。大量的测试数据表明,该方法能够有效改进FY-2可见光通道图像定位精度。几何精校正后,可见光通道图像在南北方向上的定位精度提高了31.06%,东西方向上的定位精度提高了45.21%。分析指出FY-2可见光通道图像几何精校正前后,定位精度在星下点地方时正午前后均达到最佳状态,且南北方向上的定位精度优于东西方向上的精度。同时,统计分析结果表明,提出的方法成功率达到95.29%。This paper addresses the issue on automatic geometric precision correction for Fengyun-2（FY-2） meteorological satellite.Firstly,the binary landmark template is obtained under the FY-2 nominal projection,and then the binary FY-2 images are obtained by Bayes posterior probability.Maximum Cross Correlation is used to find the landmark mismatches between the binary landmark template and the binary FY-2 images.Quality control measures are used to guarantee the correct landmark matching ratios.Finally,the Direct Linear Transformation（DLT） is used to geometrically precise correct the FY-2 imagery.Tests have shown that this method can effectively improve the FY-2 image navigation accuracy.After the geometric precision correction,the image navigation accuracy improves 31.06% in the south-north direction and 45.21% in the east-west direction,respectively.The analysis has shown that with pre and post geometric precision correction,the FY-2 visible channel image navigation accuracy will be at the best status about Sub-Satellite Poin（tSSP） noon.And with pre and post geometric precision correction,the south-north image navigation accuracy of the FY-2 visible channel is better than that of the east-west.The successful ratio of this method can achieve 95.29%.

关 键 词：风云二号 几何精校正 自动地标匹配 

分 类 号：TP751[自动化与计算机技术—检测技术与自动化装置]