利用光学阴影特征进行点位预测的星载合成孔径雷达影像灯杆提取方法  

Spaceborne Synthetic Aperture Radar Image Lamp Post Extraction Method Using Optical Shadow Feature for Point Prediction

作　　者：李佳豪 靳国旺[1,2] 熊新 叶豪[1] 王佳俊 杨鹤 Li Jiahao;Jin Guowang;Xiong Xin;Ye Hao;Wang Jiajun;Yang He(Institute of Geospatial Information,Information Engineering University,Zhengzhou 450001,Henan,China;Key Laboratory of Smart Earth,Beijing 100094,China;Transportation Development Center of Henan Province,Zhengzhou 450001,Henan,China)

机构地区：[1]信息工程大学地理空间信息学院,河南郑州450001 [2]智慧地球重点实验室,北京100094 [3]河南省交通事业发展中心,河南郑州450001

出　　处：《光学学报》2024年第24期280-291,共12页Acta Optica Sinica

基　　金：国家自然科学基金(42201492);2022年度河南省交通运输科研资金计划(2022-3-2)。

摘　　要：合成孔径雷达(SAR)影像中灯杆目标的准确检测对于星载SAR影像地面控制点提取具有重要意义。为了有效提取星载SAR影像中灯杆目标,本文设计了一种利用光学阴影特征进行点位预测的SAR影像灯杆提取方法,该方法以高分辨率光学影像为辅助数据,通过对光学影像形态学闭运算与Gabor滤波处理,增强窄暗阴影信息表达,结合低阈值模板匹配与自适应密度空间聚类算法,以获取灯杆目标粗略地理坐标。利用距离多普勒模型将灯杆目标粗略地理坐标反编码至SAR影像坐标系,设置窗口检测邻近强散射目标点,采用限制搜索象限的点目标约束改正策略,通过点目标分析法实现灯杆目标的亚像元定位。本文方法充分借助高分辨率光学影像中灯杆阴影信息,提高了SAR影像中灯杆目标提取的可行性与准确性。采用高分辨率无人机影像与高分三号SAR影像进行了灯杆目标提取实验,与传统目视解译对比后,验证了本文方法的有效性。通过增加通用性分析实验,验证了本文方法的通用性。Objective As the primary data for topographic surveying and mapping,ground control points provide important control information for the production of military and civilian basic surveying and mapping products.Traditional ground control point collection mainly relies on a global satellite navigation system and field collection,which is timeconsuming and laborintensive.With the significant improvement of domestic synthetic aperture radar(SAR)satellite orbiting technology,it is now possible to automatically extract a wide range of ground control points using domestic spaceborne SAR images.As an essential feature target in the road environment,lamp posts have the characteristics of a wide distribution range and stable target.As the typical robust targets in the natural environment,lamp posts have become one of the best choices for ground control point alternatives.Due to the particular imaging method of SAR image,the lamp post target feature presents as an isolated point target scatterer in mediumlow resolution spaceborne SAR images.However,there are many point target scatterers in the natural scene,and the influence of image speckle noise makes it more difficult to extract the lamp post target directly in SAR images.Therefore,the effective extraction of the lamp post target in SAR images has become the primary issue in studying ground control point extraction using SAR images.Methods The main flow of the method is as follows:1)The optical image is sharpened using the image morphology closedcomputing method to improve the expression of narrow and dark target information in the image.Combining with the sun’s altitude angle at the moment of acquiring the optical image,Gabor filtering is performed on the image to enhance the narrow and dark information of the image.2)Any lamp post target in the narrow and dark informationenhanced image is selected as a template.Then,the template is searched for using NCC matching in the filtered image to obtain the lamp post target points.The template is searched to get the lamp post

关 键 词：合成孔径雷达 控制点提取 灯杆目标 光学阴影 点位预测 

分 类 号：P237[天文地球—摄影测量与遥感]