一种基于差分技术的无人机影像高效拼接方法

An efficient UAV images mosaic method based on difference technology

针对传统基于特征匹配的无人机影像拼接效率低,依靠大量野外控制点才能满足精度要求的问题,该文提出了一种基于差分动态后处理(PPK)技术的高效拼接方法;首先,采用不共线的三天线配置方案,对无人机系统进行改装,建立载波相位双差模型,解算出双基线约束下的无人机影像位姿参数;然后,根据相机每次曝光对应的坐标和姿态角计算影像之间的单应变换矩阵,完成相邻影像间的精确配准;最后,实现从单个影像对到整个区域影像的高效拼接。实验结果表明,该方法可省去布设野外控制点的复杂工序,在保证拼接效果和精度的同时,效率得到了极大改善。

Traditional unmanned aerial vehicle(UAV) images mosaic based on feature matching is inefficient,and a large number of ground control points(GCPs) should be used to meet the accuracy requirements. To solve the above problems,this paper proposed an efficient mosaic method based on post processed kinematic(PPK) technology. Firstly,the UAV system was reconstructed with a configuration scheme of three non-collinear antennas. Through carrier phase double difference model,the pose parameters of UAV images were calculated under double baseline constraints. Then,the homography matrixes between images were deduced according to the coordinates and attitude angles of each exposure. Finally,an images mosaic method from a single pair to the whole region was realized. Experimental results showed that the method saved the complicated process of setting up GCPs. While ensuring the effect and accuracy,the efficiency of images mosaic was greatly improved.