近年来,随着计算机技术的快速发展和装备高清相机的四旋翼无人机的普及,基于被动视觉法的建筑物三维重建逐渐成为计算机视觉和图形学领域的热点。然而,现有的被动视觉法针对建筑建模时存在耗时长、局部细节重建效果差等问题。针对这些不足,提出一种基于无人机航拍序列的建筑三维模型重建方法。首先,利用运动恢复结构的方法,对无人机针对目标建筑航拍采集的照片序列恢复建筑周边场景的稀疏点云;同时,采用RANSAC方法,提取地面和建筑立面;进而对点云进行聚类,以提取出构成建筑的稀疏点云,再依据建筑稀疏点云得到建筑的柱状模型;最后,对该模型进行平整化处理,得到保持建筑顶部轮廓细节的三维模型。实验结果表明,利用所提方法可以快速得到建筑的三维模型,同时能较好地保持建筑顶部的轮廓细节。
In recent years,with the rapid development of computer technology and the popularity of four-rotor unmanned aerial vehicles equipped with high-definition cameras,three-dimensional reconstruction of buildings based on passive scanning has become a hot issue in the research field of computer vision and graphics.However,current passive scanning methods for modeling are characterized with such flaws as time-consuming reconstruction and poor quality in the reconstruction of local details.In view of these shortcomings,a three-dimensional model reconstruction method has thus been proposed based on UAV aerial sequences.First,the SFM method is adopted to recover the sparse point cloud of the surrounding scene from the aerial image collection of the target building.Next,by adopting the RANSAC method,an effort has been made to extract the ground and the building facades.And then the point clouds are clustered and extracted to obtain the columnar model of the building.Finally,the3D model of the building is obtained by smoothing the columnar model.The experimental results show that the3D model of the building can be obtained quickly by adopting the above-mentioned method,with the contour details of the top of the building well preserved.