光学学报, 2017, 37 (11): 1115006, 网络出版: 2018-09-07
基于共线向量与平面单应性的双目相机标定方法 下载: 1028次
Binocular Camera Calibration Based on Collinear Vector and Plane Homography
机器视觉 双目标定 畸变矫正 单应性 共线向量 machine vision binocular camera calibration distortion correction homography collinear vector
摘要
现有双目相机标定的方法是通过矩阵变换求得各个相机间的旋转平移关系,再通过优化求得最终参数。非线性优化步骤多,相机内外参数与镜头畸变存在耦合,时间花费较大。提出一种畸变矫正与平面单应性矩阵结合的双目相机标定方法。根据三维空间直线投影到像平面仍然是直线的法则,对于无畸变的图像,直线上任意两点所构成的向量的方向相同时向量夹角应为零。基于此特征求解双目相机的畸变系数,再通过平面单应矩阵构造测量矩阵,然后通过矩阵分解求得相机内、外参的初值,最终通过非线性优化求得双目相机的各个参数。仿真和实验结果证明,该方法稳定性高,精度与传统标定方法的精度相当,且计算时间短,标定效率优于传统标定方法。
Abstract
The current approach for binocular camera calibration is to obtain the rotation and translation relationship between cameras through matrix transformation, and the final parameters are obtained by optimization. The nonlinear optimization procedure is tedious, and the internal and external parameters of the camera are coupled with the lens distortion. We present a calibration method for the binocular camera with the combination of a distortion correction and a plane homography matrix. Firstly, based on the principle that three-dimensional linear projection to the image plane is still a straight line for the image without distortion, while any two points on the right line of vectors has the same direction, the direction of the vector angle should be zero. The distortion coefficient can be solved based on this characteristics. Then the measurement matrix is constructed by plane homography matrix, and the initial values of inside and outside parameters of the camera are obtained through matrix decomposition. Finally, all parameters of binocular camera are calculated by the nonlinear optimization. Simulations and experimental results show that this method is highly stable, and has equal accuracy compared to the traditional calibration methods. It spends less time and has better efficiency than the traditional calibration methods.
邹朋朋, 张滋黎, 王平, 汪启跃, 周维虎. 基于共线向量与平面单应性的双目相机标定方法[J]. 光学学报, 2017, 37(11): 1115006. Pengpeng Zou, Zili Zhang, Ping Wang, Qiyue Wang, Weihu Zhou. Binocular Camera Calibration Based on Collinear Vector and Plane Homography[J]. Acta Optica Sinica, 2017, 37(11): 1115006.