一种基于参数重估计和分层匹配的PTZ相机参数修正算法

由于多种因素的影响,PTZ(pan-ti lt-zoom)相机经过长时间运行后其参数会偏离真实值,因 此有必要对相机参数进行修正。针对现有算法参数修正精度低、适应能力弱等问题,提 出了一 种改进的基于参数重估计和分层匹配的参数修正算法。算法通过引入参数重估计策略,避免 了参数 修正过程中的误差累积,提高了参数修正的精度；通过设计分层匹配和特征传播步骤,增强 了算法 对不同尺度图像的适应性。实际场景中的多组实验结果表明,本文算法可以准确修正PTZ相 机参数,并且较现有方法更具优越性。

A parameter correction algorithm for PTZ camera based on parameter refinement strategy and hierarchical feature matching

Most modern surveillance systems make use of pan-tilt-zoom (PTZ) cameras.Howev er,due to the influence of many factors,the (pan and tilt) coordinates reported by the PT Z cameras become inaccurate after many hours of operation.As the existing parameter correction method is not adaptable enough for large scale images and provides results with low accuracy,a parameter correction algor ithm based on parameter refinement strategy and hierarchical feature matching is presented in this paper .In the offli ne stage,the parameter refinement strategy is introduced to compute the pose angle of each 3D point in the surveillance scene, which can effectively improve the accuracy of parameter correction.In the onlin e stage,a hierarchical matching and correspondence propagation method is designed to generate pairwise correspondence between observed image and pose angle set,which can effectively improve the adaptive ca pacity of parameter correction algorithm for different scale images.Experimental results demonstrate that the proposed method can accurately correct the parameters of the PTZ camera,and it has better accur acy compared with the classical method.