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.
李天祺, 王建超, 吴芳, 赵政, 张文凯. 基于多算法水边线提取的潮滩DEM构建[J]. 国土资源遥感, 2021, 33(1): 38-44.
LI Tianqi, WANG Jianchao, WU Fang, ZHAO Zheng, ZHANG Wenkai. Construction of tidal flat DEM based on multi-algorithm waterline extraction. Remote Sensing for Land & Resources, 2021, 33(1): 38-44.
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2021, Vol. 33 
), 王建超, 吴芳, 赵政, 张文凯
