基于多视影像匹配模型的倾斜航空影像自动连接点提取及区域网平差方法

Automatic Tie-point Extraction Based on Multiple-image Matching and Bundle Adjustment of Large Block of Oblique Aerial Images

自动可靠地获取精确且均匀分布的连接点并进行区域网平差解算,是使用倾斜航空影像进行高精度测绘、三维信息提取和三维城市模型构建等应用的前提。本文提出了一种实用化的大重叠率倾斜航空影像的全自动连接点匹配和联合区域网平差方法。一方面,针对倾斜航空影像因遮挡严重、尺度变化大和几何变形严重而引起的同名点匹配困难问题,充分利用POS数据和平均飞行高度等初始数据,同时顾及这些数据的误差,通过有效组合一种改进的ASIFT算法和基于窗口的多角度多视影像匹配模型(WMVM),使用由粗到细的多分辨率分层匹配策略完成连接点的全自动提取;另一方面,在传统的最小二乘光束法平差的基础上,根据倾斜航空影像数据的特点,提出了基于稳健估值原理的粗差自动探测与剔除关键算法。最后,利用多组典型试验区域的倾斜航空影像数据试验结果验证了所提算法的可靠性、精度和实际性能。

Due to advantages such as ease of interpretation,completeness through mitigation of occluding areas,as well as system accessibility,the aerial oblique images have found their place in numerous civil applications.However,for these applications high quality orientation data are essential.A fully automatic tie-point extraction procedure is developed to precisely orient the large block of oblique aerial images,in which a refined ASIFT algorithm and a window-based multiple-viewing image matching（WMVM）method are combined.In this approach,the WMVM method is based on the concept of multi-image matching guided from object space and allows reconstruction of 3Dobjects by matching all available images simultaneously,and a square correlation window in the reference image can be correlated with windows of different size,shape and orientation in the search images.Then another key algorithms,i.e.the combined bundle adjustment method with gross-error detection removal algorithm,which can be used for simultaneously orient the oblique and nearly-vertical images will be presented.Finally,through the experiments by using real oblique images over several test areas,the performance and accuracy of the proposed method is studied and presented.