基于多算法水边线提取的潮滩DEM构建  

Construction of tidal flat DEM based on multi-algorithm waterline extraction

作　　者：李天祺 王建超 吴芳 赵政 张文凯 LI Tianqi;WANG Jianchao;WU Fang;ZHAO Zheng;ZHANG Wenkai(China Aero Geophysical Survey and Remote Sensing Center for Natural Resources, Beijing 100083, China)

机构地区：[1]中国自然资源航空物探遥感中心,北京100083

出　　处：《国土资源遥感》2021年第1期38-44,共7页Remote Sensing for Land & Resources

基　　金：中国地质调查局地质调查项目“长江上游重大区航空遥感地质调查”(编号:DD20190514)资助。

摘　　要：遥感水边线法构建潮滩数字高程模型(digital elevation model,DEM)是获取大范围淤泥质潮滩地形的有效途径,准确提取水边线是潮滩DEM构建的关键。受潮情及滩面的影响,不同影像中的水边线在光谱与纹理上差异较大,单一方法难以准确地提取水边线。鉴于此,本文提出一种基于多算法水边线提取的潮滩DEM构建方法。根据瞬时潮情对多期水边线进行分类,应用边缘检测、阈值分割、面向对象分割与改进分水岭方法对不同类型水边线分别提取,通过对潮汐数据多项式插值计算水边线的瞬时潮位,构建潮滩DEM。本文以莱州湾西侧潮滩为研究区,利用多期GF-1 WFV影像与验潮站潮汐数据构建潮滩DEM。通过野外实测高程对DEM反演结果进行精度评价,反演值与实测值相关性较高,R2=0.86,误差分布在0.31~0.78 m之间,中误差为0.17 m。结果表明,基于多算法水边线提取的潮滩DEM构建可以有效地获取潮滩近似地形。The waterline method is an effective way to obtain a large area of silty tidal flat terrain.Accurate extraction of the waterline is the key to the construction of the tidal flat digital elevation model(DEM).Affected by the tidal conditions and the surface of the tidal flat,the waterlines in different satellite images have large differences in spectrum and texture.It is difficult to extract waterlines accurately using a single method.In this paper,a tidal flat DEM construction method based on multi-algorithm waterline extraction is proposed.The waterlines are classified into four categories according to the tide conditions and are extracted by edge detection,threshold segmentation,object-based segmentation,and improved watershed algorithm respectively.Then,combined with the instantaneous tide level of waterlines,the tidal flat DEM is constructed.In this paper,the method was verified using Laizhou Bay as the research area.There was a high correlation between the inversion elevation and the measured elevation,R2=0.86,and relative error was between 0.31~0.78 m.It is shown that the method in this paper can effectively obtain the approximate topography of the tidal flat.

关 键 词：水边线提取 淤泥质潮滩 数字高程模型 分水岭算法 

分 类 号：TP79[自动化与计算机技术—检测技术与自动化装置]