一种多镜头拼接式全景成像系统的整体标定方法  

An overall calibration method of multi-camera stitching panoramic imaging system

作　　者：李亚云 姚连璧[2] Li Yayun;Yao Lianbi(Shanghai Municipal Institute of Surveying and Mapping,Key Laboratory of Spatial-temporal Big Data Analysis and Application of Natural Resources in Megacities,MNR,Shanghai 200063,China;Tongji University,Shanghai 200092,China)

机构地区：[1]上海市测绘院自然资源部超大城市自然资源时空大数据分析应用重点实验室,上海200063 [2]同济大学,上海200092

出　　处：《工程勘察》2022年第9期49-54,共6页Geotechnical Investigation & Surveying

基　　金：上海市科技计划项目资助(项目编号:21DZ1204100)。

摘　　要：本文针对多镜头拼接式成像系统在外业量测过程中因客观条件限制导致个别镜头缺乏控制点无法计算其外方位元素,进而使得全景相机无法完整实现三维真实场景构建的问题,提出一种多镜头拼接式全景成像系统的整体标定方法,标定的内容包括:镜头内方位元素、镜头相对位置和姿态。相机采用直接线性变换算法结合畸变模型进行内方位标定和相片校正,实现非量测型相机向量测型相机的转化;在此基础上,利用经典空间后方交会法求解每台相机在同一时刻的外方位元素,并进一步根据坐标转换来标定镜头之间的相对位置和姿态,实现多个镜头的整体化及其外参数的自由转换。实验证明,多镜头拼接式全景成像系统的内标定精度能达到0.5个像素,在利用镜头相对位置和姿态反算外方位元素时能达到0~2.5mm的线元素精度以及0~10′的角元素精度,很好地解决了室外个别镜头外方位元素计算困难的问题,且其在交通安全检测、高速公路三维真实场景建模方面均得到了较好的应用。In order to solve the problem that some lenses lack of control points because of the field objective conditions so that exterior orientation elements couldn’t be calculated when the imaging system were used outside,and then the panoramic camera couldn’t be fully applied to the construction of 3 D real scene,a concept about overall calibration of multi-camera stitching panoramic imaging system was proposed.The overall calibration includes:interior orientation;relative position,and exterior orientation of cameras.A direct linear transformation algorithm combined with distortion model was used to demarcate the interior orientation and revise the photos,and achieved the transformation from non-measuring camera to measuring camera.On this basis,the classic space resection method was then used to solve the exterior orientation elements of each camera at the same time and further to demarcate the relative position and attitude between lenses through the way of coordinate conversion,realized the integrity of multiple lenses and free conversion of its external parameters.Experiments show that,the precision of interior orientation of multi-camera stitching panoramic imaging system can achieve 0.5 pixels.In addition,the precision of line elements can achieve 0~2.5 mm and angle can achieve 0~10′when the relative position and orientation of lenses is used to inverse calculate the exterior orientations.Therefore,the overall calibration could be a good solution to solve the problem that exterior orientations of some lenses is difficult to be calculated outdoors and it also has a good application in traffic safety detection,highway 3 D real scene modeling.

关 键 词：全景相机 直接线性变换 近景摄影测量 相对位置和姿态 整体标定 

分 类 号：P234.1[天文地球—摄影测量与遥感]