Greedy calibration method for binocular camera system via characteristic homography matrix  

基于特征单应矩阵的双目摄像机系统贪婪标定方法(英文)

作　　者：刘天亮[1] 金飞逸[1] 罗立民[1] 

机构地区：[1]东南大学影像科学与技术实验室,南京210096

出　　处：《Journal of Southeast University(English Edition)》2009年第2期193-198,共6页东南大学学报（英文版）

摘　　要：A plane-based and linear camera calibration technique without considering lens distortion is proposed in a greedy and intuitive framework for the binocular camera system. Characteristic homography matrix and consistency constraints in close range are employed in this calibration. First, in order to calculate the internal geometries of the cameras, total least-square fitting as a robust tool for the geometrical cost function is exploited to recover the accurate principal point of each camera from all the characteristic lines of the homography matrices for all model planes. Secondly, generic prior knowledge of the aspect ratio of pixel cells is incorporated into the system to obtain the exact principal length in each camera. Thirdly, extrinsic geometries are accurately computed for all planar patterns with respect to each monocular camera. Finally, the rigid displacement between binocular cameras can be obtained by imposing the consistency constraints in 3-space geometry. Both simulation and real image experimental results indicate that reasonably reliable results can be obtained by this technique. And the proposed method is sufficient for applications where high precision is not required and can be easily performed by common computer users who are not experts in computer vision.在贪婪及直觉的框架下,针对双目摄像机系统提出一种基于平面模板且未考虑光学畸变的线性标定方法.利用单应矩阵的特性及近距离的双目一致性约束进行标定.首先,为计算双摄像机内部几何特性,根据所有模板平面各自的单应矩阵具有特征线的属性,构造具有几何意义的成本函数;采用鲁棒的总误差最小二乘拟合策略,恢复精确的主点坐标.其次,引入像素单元纵横比的先验信息,求取精确的主轴长.然后,精确地获取所有平面模板关于各自相机的外部几何.最后,利用强加于三维几何空间中的一致性约束来计算双目摄像机之间的刚体变换关系.仿真及真实图像实验表明,所提算法能获得较可靠的标定结果,满足精度要求不是很高的应用需求,且对计算机视觉不是很内行的普通用户,能较容易地实现.

关 键 词：close range CALIBRATION homography matrix consistency constraint STEREOVISION 

分 类 号：TP391.41[自动化与计算机技术—计算机应用技术]