基于一维靶标的多摄像机现场全局校准  

Global Calibration of Multi-camera System Based on 1D Target

作　　者：刘震[1] 张广军[1] 魏振忠[1] 

机构地区：[1]北京航空航天大学精密光机电一体化技术教育部重点实验室,北京100083

出　　处：《机械工程学报》2009年第4期161-165,共5页Journal of Mechanical Engineering

基　　金：国家自然科学基金资助项目(50727502)。

摘　　要：基于一维靶标特征点共线的特点,提出一种多摄像机全局校准方法。以其中一个摄像机坐标系为基础,建立全局坐标系,称该摄像机为基础摄像机。在基础摄像机与待校准摄相机前将一维靶标无约束摆放至少两次。计算每个摆放位置一维靶标所在空间直线在图像中的消影点。结合一维靶标点共线的特点,分别求解全部一维靶标点在两个摄像机坐标系下三维坐标。通过两个摄像机坐标系下一维靶标对应特征点的三维坐标求解待校准摄像机坐标系到基础摄像机坐标系的转换矩阵,采用非线性优化方法求解转换矩阵的最优解。当摄像机多于两个时,通过两两摄像机校准的方式完成多摄像机全局校准。该方法不需要高精度外部辅助设备、简单灵活、实用性强。试验证明该方法灵活方便,切实可行。Based on the property that all feature points of 1D target are collinear, a global calibration method of multi-camera system is proposed. The global coordinate flame is constructed based on one of cameras, called the base camera. 1D dimensional target is positioned arbitrarily in front of both the base camera and the camera to be calibrated. The vanishing point of 1D target in the image is determined. According to the property that all feature points of 1D target are collinear, the coordinates of all feature points on 1D target in each camera coordinate frame are computed. The transformation matrix from the camera to be calibrated to the base camera is solved, and optimized by using the non-linear optimization method. The global calibration of multi-camera system is realized by pair-wise calibration between the base camera and each of the cameras to be calibrated. The proposed method can be carried out without any high-accuracy 3D measuring equipment. Experiment results show that the method is simple and practical.

关 键 词：机器视觉 多摄像机 全局校准 一维靶标 

分 类 号：TP391[自动化与计算机技术—计算机应用技术]