基于DEM的山区遥感图像地形校正方法

基于地表反射为各向异性的假定,可以将遥感图像的地形校正分为光照和反射率校正两部分。基于6S大气校正模型和数字高程模型(DEM)对山区遥感图像进行光照和反射率校正,通过消除遥感图像中大气和地形的影响,反演得到地表反射率。通过对江西兴国县TM图像的实验,实现了对山区遥感图像的地形校正。对模型中的大气参数进行了敏感性分析,发现大气参数的误差对地表反射率的反演精度影响较小。

DEM Based Remotely Sensed Imagery Topographic Correction Method in Mountainous Areas

On the basis of the anisotropy of land surface reflectance,the topographic correction of remotely sensed imagery includes illumination correction and reflectance correction.Both of the illumination and reflectance correction were performed based on Digital Elevation Model(DEM) and 6S atmospheric correction model in this paper.According to removing atmospheric and topographic effects on remotely sensed imagery,the land surface reflectance can be retrieved.One scene of TM imagery over Xingguo county,Jiangxi province was used for validation.The results show that this method can remove the topographic effects of remotely sensed imagery in mountainous areas.From the sensitivity analysis of the atmospheric parameters in the topographic correction model,it is found that the impact of retrieved accuracy of the land surface reflectance due to the error of the atmospheric parameters is very small.