室外环境下PTZ摄像机全自动标定技术及其应用  

An Automatic Calibration Method for Outdoor PTZ Cameras and Its Applications

作　　者：张雪波[1] 路晗[1] 方勇纯[1] 李宝全[1] 

机构地区：[1]南开大学机器人与信息自动化研究所,天津300071

出　　处：《机器人》2013年第4期385-393,共9页Robot

基　　金：国家自然科学基金资助项目(61203333);教育部高等学校博士学科点专项科研基金资助项目(20120031120040);天津市应用基础与前沿技术研究计划资助项目(13JCQNJC03200)

摘　　要：针对室外环境下的PTZ(pan-tilt-zoom)摄像机,提出了一种全自动运行且精度较高的摄像机标定算法,并将其成功地应用于视频监控系统下人体的身高测量中.具体而言,首先将摄像机模型分解为变焦转换模型与定焦摄像机参数模型.对于前者,提出了一种基于多参考点的变焦转换模型标定方法.对于后者,利用摄像机旋转角度信息,对定焦摄像机模型进行了在线标定.由于将变焦中心与主点位置作为相互独立的变量,在变焦转换模型与定焦模型中分别进行标定,因此确保了模型的完整性与准确性;引入了多个参考点,使得本文方法较好地解决了多倍变焦情况下模型误差较大与特征匹配点过少等问题,提高了标定的精度.基于自标定结果,提出了一种适用于监控环境的人体身高测量方法.实验结果表明本文的自标定算法与身高测量方法具有良好的性能.An automatic method is proposed to calibrate an outdoor PTZ（pan-tilt-zoom） camera system with high precision,which is successfully applied to human height measurement in visual monitoring systems.Specifically,the whole camera is divided into a zoom transformation model to deal with the changing zoom parameters,and a fixed focal camera parameters model.For the former,a calibration method based on multiple reference points is presented.For the latter,rotation angle information of the camera is utilized to conduct on-line calibration for the fixed focal camera.For the reason that both the zoom center and the principal point are considered as independent variables which are calibrated in zoom transformation model and fixed focal camera model respectively,the proposed model can achieve high accuracy.Furthermore,since multiple reference points are adopted to guarantee that the modeling error is small and there exist sufficient matching features even when the zooming range is large,high calibration precision is achieved.Based on the self-calibration results,a height measurement approach for the human in monitoring environments is proposed.Experimental results are provided to demonstrate the performance of both the self-calibration and height measurement algorithms.

关 键 词：PTZ摄像机 全自动标定 变焦转换模型 高度测量 

分 类 号：TP182[自动化与计算机技术—控制理论与控制工程]