基于高分七号卫星影像的高程变化信息提取方法研究
Study on Extraction Methods of Elevation Change Information Based on GaoFen-7

为更加准确及时掌握地形地势变化情况，该文利用多时相高分七号卫星立体影像获取同一区域不同时相数字地表模型(Digital Surface Model, DSM)，分别采用差值法和比值法提取该时段内高程变化信息，并对两种提取方法得出的结果进行对比研究。实验表明：采用差值法提取更为精准，效果更佳，其变化信息提取正确率达到80%以上，提取方法可行、可靠，可用于实景三维成果的变化发现，对地形级实景三维的更新维护有重要帮助作用。
To more accurately and timely grasp the terrain and terrain changes, this paper used the multi- phase GF7 stereo images to obtain the DSM of the same region at different time phases, respectively used the difference method and the ratio method to extract the elevation change information in this period, and compared the results obtained by the two extraction methods. The experiment results show that the difference method is more accurate and effective, and the accuracy of the change in-formation extraction is more than 80%. The extraction method is feasible and reliable, and it can timely grasp the terrain changes of the target area, which is of great help to the change discovery, update and maintenance of 3D Real Sense.