一种用于小景深相机的快速标定算法  

A fast calibration algorithm for small depth of field camera

作　　者：黄鹏 周益航 谢中毅 宋跃 何国强 Huang Peng;Zhou Yihang;Xie Zhongyi;Song Yue;He Guoqiang(School of Mechanical and Control Engineering,Guilin University of Technology,Guilin 541006,China;Key Laboratory of Advanced Manufacturing and Automation Technology in Guangxi Universities,Guilin University of Technology,Guilin 541006,China)

机构地区：[1]桂林理工大学机械与控制工程学院,桂林541006 [2]桂林理工大学广西高校先进制造与自动化技术重点实验室,桂林541006

出　　处：《电子测量技术》2024年第12期148-154,共7页Electronic Measurement Technology

基　　金：广西科技计划资助项目(桂科AB22035041);梧州市中央引导地方科技发展资金项目(202201001);桂林理工大学科研启动基金(GUTQDJJ2016014)项目资助。

摘　　要：高速在线视觉测量系统中,小景深相机难以从不同方位获取标定物清晰图像,从而导致张氏标定算法无解或计算误差较大,为此提出一种用于小景深相机的快速精确标定算法。获取位于待标定平面和与之平行平面上的一组标定物图像,线性求解得到相机镜头光心到待标定平面的高度,并根据相机姿态简化旋转矩阵,最后利用位于待标定平面的标定图像计算出相机内外参数。实验结果表明,标定图像组数最好取在13组左右,但仅采用一组标定图像也可以实现较高精度标定。在相机景深较小的情况下,该方法重投影均方根误差小于0.74 pixel,标定精度较张氏方法提高了约33%。In high-speed online visual measurement systems,it is difficult for small depth of field cameras to obtain clear images of calibration objects from different directions,resulting in the Zhang calibration algorithm having no solution or significant calculation errors.Therefore,a fast and accurate calibration algorithm for small depth of field cameras is proposed.Obtain a set of calibration object images located on the plane to be calibrated and parallel to it,linearly solve to obtain the height of the camera lens optical center to the plane to be calibrated,simplify the rotation matrix based on the camera posture,and finally use the calibration images located on the plane to calculate the camera′s internal and external parameters.The experimental results show that it is best to set the number of calibration image groups around 13,but using only one set of calibration images can also achieve high-precision calibration.In cases where the depth of field of the camera is small,this method has a root mean square error of less than 0.74 pixels for reprojection,and the calibration accuracy is improved by about 33%compared to Zhang′s calibration.

关 键 词：相机标定 小景深相机 单应性矩阵 误差分析 

分 类 号：TN391.41[电子电信—物理电子学]