遥感影像阴影多波段检测与去除理论模型研究  

Study on Multispectral Detecting Shadow Areas and A Theoretical Model of Removing Shadows from Remote Sensing Images

作　　者：虢建宏[1] 田庆久[1] 吴昀昭[2] 

机构地区：[1]南京大学国际地球系统科学研究所,江苏南京210093 [2]南京大学地球科学系,江苏南京210093

出　　处：《遥感学报》2006年第2期151-159,共9页NATIONAL REMOTE SENSING BULLETIN

基　　金：江苏省高技术研究项目"水稻冠层养分高光谱遥感数字信息采集关键技术研究(BG2004321)"

摘　　要：阴影是遥感影像的基本特征之一,它使地物目标反映的信息量有所损失或受到干扰,而去除阴影一直是遥感影像处理的难题。从研究遥感影像阴影产生机理出发,提出了一种多波段检测阴影的方法和基于能量信息补偿去除阴影的理论模型。通过IKONOS影像进行方法与模型验证,真实再现阴影区地物特征,增加影像信息量,提高数据质量。Generally, there are two contents of detecting shadow areas and eliminating shadows in removing shadows of remote sensing images. In this study, the conclusion was drawn from the forming mechanism of remote sensing images and the reflection spectral characteristic of surface objects, which are the datum of green band having very high correlation with that of blue band, and the shadows of green band being obviously stronger than that of blue band. The reduced（divided） image derived from green band subtracted from（ divided by） blue band, can be used to detect shadows with threshold value, due to the more differences between shadow areas and non-shadow areas in it. This method of detecting shadows is related to variational reflectance of the same object. In addition, the precision of detecting shadows with Histogram threshold value in nearinfrared band is higher than the other＇s. This method of detecting shadows is related to the reflectance of surface objects. Multispectral detecting shadow is the combination of the two methods. Shadow is sheltered by the objects higher than the ground from direct irradiance, the lost information is direct irradiance mainly, which is compensated, then the shadows could be removed. In this paper, a theoretical model, which was based on the radiation transfer theory to calculate the proportions of direct irradiance, diffuse irradiance and environment irradiance, was put forward to remove shadows through compensating direct irradiance. Finally, the method and the model were validated using the IKONOS images, and the results were turned up trumps.

关 键 词：遥感 阴影检测 阴影去除 模型 IKONOS 

分 类 号：TP751[自动化与计算机技术—检测技术与自动化装置]