光学 精密工程, 2013, 21 (10): 2664, 网络出版: 2013-11-01
野外大视场双目视觉物体定位监测系统的单参数快速标定
Fast calibration for binocular vision measuring system with a large field
双目视觉 摄像机标定 快速标定 大视场 精度验证 binocular vision camera calibration fast calibration large field of view precision analysis
摘要
提出了一种只对相机水平偏角进行现场校准的标定方法用于野外远距离、大视场、双目视觉物体定位监测系统的快速标定。该方法通过合理考虑视觉传感器的调平装置,结合现场使用过程中相机焦距值固定的特点,简化了测量模型,减少了待标定参数; 只需要测得监测中心和相机在大地坐标系中的经纬度坐标及监测中心的图像坐标即可完成系统标定。由于不需要高精度靶标,从而克服了靶标移动及摆放对标定过程的影响。在实际使用中,对2 km以外400 m×800 m的区域进行监测时,相对定位误差小于0.25%,其中由焦距值误差引起的相对定位误差不超过0.07%。该摄像机标定方法在保证测量精度的同时,具有易实现、用时少等优点,适用于野外大视场环境下物体的快速定位监测。
Abstract
An improved calibration method that just needs to calibrate one camera parameter was proposed to calibrate a positing and monitoring system for the objects with long distances, larger view field and binocular vision. By considering the leveling device of a vision sensor and combining the condition that the focal length of the camera was fixed in the field,the measurement model was simplified, and parameters to be measured were reduced. The system calibration could be completed when the geographic coordinates of the measuring area center and the cameras, as well as the center coordinates in the image were obtained. With no need for a higher precision target, the effect of target movement and layout on the calibration can be ignored. In application to monitoring an area of 400 m×800 m at 2 km away, the relative error is less than 0.25%, in which that caused by the error of the focal length is less than 0.07%. The proposed method overcomes the difficulty brought by the movement of the target. The improved method could ensure the accuracy, and it is easy to be realized with less time and is suitable for measuring the coordinate in a large field of view.
王向军, 王晶, 刘峰, 王剑, 张召才. 野外大视场双目视觉物体定位监测系统的单参数快速标定[J]. 光学 精密工程, 2013, 21(10): 2664. WANG Xiang-jun, WANG Jing, LIU Feng, WANG Jian, ZHANG Zhao-cai. Fast calibration for binocular vision measuring system with a large field[J]. Optics and Precision Engineering, 2013, 21(10): 2664.