光学学报, 2015, 35 (7): 0712003, 网络出版: 2015-07-01
晃动平台上对空拍摄大视场摄像机的标定方法
A Camera Calibration Method for Large Field Camera Pointing at Sky on Sway Platform
测量 摄像机标定 晃动平台 大视场 无人机 measurement camera calibration sway platform large field unmanned aerial vehicle
摘要
针对晃动平台对空拍摄大视场摄像机难以标定的情况,提出了利用无人机(UAV)作为动态控制点来现场标定摄像机参数的方法。该方法控制无人机在摄像机视场内飞行,并用与晃动平台固联的无人机定位测量系统对无人机位置进行测量,从而整个飞行过程中的无人机位置均可当作控制点对摄像机进行标定。实验中控制点数目充足, 易满足控制点在空间和在图像上均匀散布的要求, 可以准确求解摄像机内外参数。突破了无法在视场中布设传统像机标定方法所需控制点,使晃动平台上大视场摄像测量无法现场采集参考图像进行高精度标定的局限。对实验条件要求低,最少只需要晃动平台基准坐标系下2 个基准点和方位像机光心位置即可标定摄像机内外参数。该方法已成功应用于系泊状态下船舶中摄像机参数的标定。
Abstract
A camera parameters field calibration method using dynamic control points created by unmanned aerial vehicle (UAV) is presented for large field camera difficult to calibrate air photograph on sway platform. The camera continuously shoots images when UAV is flying at the field of view, the position of UAV is measured by the designed system fixed on the sway platform, thus all the UAV′ s positions in the entire flight are used as control points for camera calibration, and the control points are easily distributed in space or in the calibration image rationally, the camera parameters are solved accurately by using the sufficient number of control points and images. The proposed method overcomes the contradiction that the condition of traditional camera calibration methods often cannot be constructed in some field experiments. The proposed camera calibration method requires low field experimental conditions that demand a minimum of coordinates of two reference points and azimuth camera optical center in the reference coordinate system on sway platform. The proposed method is successfully used in applications, such as calibrating the camera in the berthed ship.
关棒磊, 孙祥一, 尚洋, 于起峰. 晃动平台上对空拍摄大视场摄像机的标定方法[J]. 光学学报, 2015, 35(7): 0712003. Guan Banglei, Sun Xiangyi, Shang Yang, Yu Qifeng. A Camera Calibration Method for Large Field Camera Pointing at Sky on Sway Platform[J]. Acta Optica Sinica, 2015, 35(7): 0712003.