ASTER立体像对提取的DEM及其精度评价

DEM extraction and accuracy evaluation based on aster stereo images

以北京怀柔风景区ASTER影像立体像对为实验数据,借助ENVI软件提取了该区域的DEM,并采用抽样检查点法对提取的DEM进行了精度评价。评价结果表明:与1∶50 000实测地形图相比,提取的DEM吻合度高,地表覆盖物、山脉等特征均较为清晰;随着控制点个数的增加,DEM的高程精度虽有波动,但中误差和标准差在总体上呈下降趋势,精度可达到10.45 m;采用ASTER立体像对提取的DEM,虽然与实测DEM相比存在一些差异,但基本能满足中小比例尺地图制图的要求。

Taking ASTER image stereo pairs of Huairou scenic spot in Beijing as experimental data,the DEM of the region was extracted with ENVI software,and the precision of the extracted DEM was evaluated by sampling checkpoint method. The evaluation results show that compared with the measured topographic maps of 1：50 000,the extracted DEM has high degree of coherence,and the characteristics of surface cover and mountain range are clear. With the increase of the number of control points,the elevation accuracy of DEM is fluctuating,but the mid error and standard deviation on the whole show a downward trend,and the accuracy can reach 10. 45 M. Although the DEM extracted by ASTER stereo image has some differences compared with the measured DEM,it can basically meet the requirements of small scale cartography