青藏铁路综合视频监控系统室外摄像机抖动频率特征分析

青藏铁路沿线多处区段常年多风,导致安装在铁塔高处的长焦摄像机产生抖动引起图像模糊,因此使用的长焦摄像机应具有防抖功能。而多个摄像机、镜头等生产厂家,均无法提供其电子防抖性能的具体参数指标,或无法给出光学/机械防抖性能参数指标来源。通过提出采用SURF算法提取匹配图像的特征点,介绍算法原理和算法实现过程,并开展算法验证和试验分析,得出大风天气条件下,青藏铁路沿线室外摄像机主要抖动频率区间为2~10 Hz。研究成果对标定摄像机的防抖性能指标具有重要参考意义。

Analysis on Jitter Frequency Characteristics of Outdoor Cameras in Integrated Video Monitoring System of Qinghai-Tibet Railway

Many districts along Qinghai-Tibet Railway are windy all the year round,which causes the long-focus cameras installed at the high place of the iron towers to jitter,resulting in blurred images.Therefore,the longfocus cameras used shall have the anti-jitter function.However,many camera and lens manufacturers cannot provide specific parameter indexes of their electronic anti-jitter performance,or give the source of optical/mechanical anti-jitter performance parameter indexes.By proposing to extract the minutiae of matching images with SURF algorithm,this paper introduces the principle and implementation process of the algorithm in detail,verifies the algorithm and carries out experimental analysis.It is concluded that the main jitter frequency range of outdoor cameras along Qinghai-Tibet Railway is 2~10 Hz under windy weather conditions.The research results are of important reference significance in defining the anti-jitter performance indexes of cameras.