三调正射影像生产中道路扭曲的快速纠正方法

土地调查中数字正射影像(DOM)底图生产是开展资源与环境监测、国情普查的基础.针对正射纠正后影像中存在大量扭曲区域,特别是道路区域,本文提出全新作业模式,即通过编辑道路扭曲区域数字高程模型(DEM),进行实时局部正射纠正来实现.高分辨测绘卫星影像高分二号和北京二号两组实验数据生产表明,该方法实现了影像道路扭曲区域的快速纠正,纠正后道路区域边缘地物没有出现明显错位现象.同时,一定数量道路区域控制点的局部纠正前后精度对比,表明该方法很大程度提高了道路扭曲区域的纠正精度,平面精度优于4 m,满足我国1:1万正射影像生产精度要求. 

A Quick Rectify Method for Road Distortion in Orthophoto Production in the Third Land Survey

It is the basis for resource and environmental monitoring and census of national conditions when orthophoto is produced as the base map in land survey. Aiming at the large number of distorted areas existing in the orthorectified image, especially the road area, this paper proposes a new method. That is to say, Real-time local orthorectification is carried out by editing DEM in the road distortion area. It shows that the method achieves a rapid rectify of the image road distortion area, There is no obvious misalignment of the road edge area after rectifying the high-resolution satellite imagery of the GF-2 and TRIPLESAT-2 experimental data. In addition, through comparing the accuracy of a certain number control points in the road area, before and after local orthorectification, it also shows that the method significantly improves the accuracy of the road distortion area, whose planar accuracy is better than 4 m. and meeting the requirements of Orthophoto production accuracy of 1∶10 000.