网络球型摄像机瞬时视场的单点校正水位连续测量方法  

A continuous water level measurement method based on single-point correction in instantaneous field-of-view of network dome camera

作　　者：刘科利[1] 赵雪莹 辛成章 刘昌军[4] 姚吉利[1] LIU Keli;ZHAO Xueying;XIN Chengzhang;LIU Changjun;YAO Jili(School of Civil Engineering and Geomatics,Shandong University of Technology,Zibo 255049,China;Shandong Provincial Institude of Land Surveying and Mapping,Jinan 255000,China;Gansu Provincial Bureau of Geology and Mineral Explorations Development,Lanzhou 730000,China;China Institute of Water Resources and Hydropower Research,Beijing 100000,China)

机构地区：[1]山东理工大学建筑工程与空间信息学院,山东淄博255049 [2]山东省国土测绘院,山东济南255000 [3]甘肃省地质矿产勘查开发局测绘勘查院,甘肃兰州730000 [4]中国水利水电科学研究院,北京100000

出　　处：《测绘通报》2024年第10期120-124,173,共6页Bulletin of Surveying and Mapping

基　　金：国家重点研发计划(2023YFC3006700);“四预”防洪灾害技术与实践。

摘　　要：基于网络球型摄像机进行洪水监测成为当今水利建设的热点之一,摄像机需进行旋转、焦距的放大与缩小等操作,才能在多视场进行流速、水位、流量一体化监测。由于摄像机传动装置制造的缺陷,在多视场切换时会出现预置点不能准确复位的问题而产生隙动差,这给从单张影像上解析水位、流速造成较大偏差,因此本文提出一种针对水位测量的隙动差校正方法。首先对预置点的水位尺进行精确标定,得到预置点水位方程参数,并在影像上选取两个特征明显的校正点;然后在连续监测中,将瞬时视场内校正点影像坐标按线性方法校正到预置点视场校正点;最后用预置点水位方程参数计算瞬时视场水位。经现场试验测试,不同瞬时视场校正点的影像坐标最大有8像素隙动差,产生水位误差达5 cm,而经本文方法计算的水位误差约为5 mm,说明本文方法对消减隙动差的影响是显著的。Flood monitoring based on network dome camera has become one of the hot spots in water conservancy construction.In order to monitor the flow rate,water level and flow rate in multi-field-of-view,the camera needs to rotate,zoom in and out the focal length.Because of the defects of the camera transmission,the preset point can't be reset accurately when the multi-field-of-view is switched,resulting in the gap error.It creates a large deviation in analyzing water level and flow rate from single image.In this paper,a method of gap error correction for water level measurement is proposed.Firstly,the water level ruler of the preset point is precisely calibrated,and the parameters of the water level equation are obtained.And two correction points with obvious features are selected on the image.Then,The image coordinates of the correction points in the instantaneous field-of-view are linear corrected to the preset field-of-view.Finally,water level in the instantaneous field-of-view is calculated by using the water level equation of the preset point.Through field test,the maximum gap error in different instantaneous field-of-view is 8 pix,and the water level error is 5 cm.But the water level error is about 5 mm by paper's method.It is shown that the paper's method can greatly reduce gap error in water level measurement.

关 键 词：洪水监测 隙动差 线性校正 水位方程 水位精度 

分 类 号：P258[天文地球—测绘科学与技术]