STUDY OF LARGE-SCALE BLOCK ADJUSTMENT WITH LASER ALTIMETRY DATA GLAS OF ZY3 IMAGES OVER SHANDONG
Keywords: ZY3, GLAS, Block Adjustment, Without Ground Control, Elevation accuracy
Abstract. In the global mapping work, there will be no control points or uneven distribution of control points. The traditional method of single scene image correction based on ground control points is not suitable for modern surveying and mapping, which has no available control points in a large range. New control data is urgently needed to make up for the influence of traditional control points on surveying and mapping. In this paper, aiming at improving the elevation accuracy of ZY-3 uncontrolled point surveying, a filtering principle based on the analysis based on waveform analysis and the stereo image pair based on tie points is proposed for the screening of GLAS laser elevation points. A new method using high-reliability laser elevation control points as the height constraint and the regional network adjustment of ZY-3 images without control points is studied. Through the experiment in Shandong Province, it is proved that the elevation accuracy of the adjustment can be improved obviously by introducing the selected laser points. The mean error of adjustment elevation is increased from −2.297 to 0.216m and the mean square error of elevation is increased from 3.193m to 2.007m, significantly improving the elevation positioning accuracy of adjustment.