后差分技术及像控点密度对无人机摄影测量精度影响研究

基于Inpho摄影测量软件对比分析后差分、单点定位的无人机影像数据，在密集像控点、稀疏像控点条件下的DOM精度及DEM精度。在1 km²的试验区布设68个像控点及检查点，通过调整参与计算的像控点数量及布设位置，采用检查点对生成的DOM及DEM精度进行验证。通过试验发现，基于后差分技术及对控制点的合理布设对无人机摄影测量成果精度的提高具有显著效果。本次试验，最高精度达到平面±4 cm，高程±9 cm。因此，后差分技术及合理像控点布设对于大比例无人机数字测图具有重要的意义。

On Influence of Post-processed Difference Technique and Image Control Point Density on UAV Photogrammetry Accuracy

Based on the Inpho photogrammetry software, the DOM precision and DEM precision of the UAV image data of post-processed difference and point positioning under the condition of dense image control points and sparse image control points are compared and analyzed. In the test area of 1 km², 68 image control points and check points are laid. By adjusting the number and layout position of image control points of the involved calculation, the inspection points are used to verify accuracy of the generated DOM and DEM. Through the experiment, it is found that the accuracy of UAV photogrammetry results is improved remarkably based on the post-processed difference technique and the reasonable layout of the control points. In this experiment, the highest precision reaches the plane ±4 cm and the elevation is ±9 cm. Therefore, post-processed differencing technique and reasonable image control point layout are of great significance for large scale UAV digital mapping.