Extraction of Watersheds from Dtm and Images with Subpixel Precision
نویسنده
چکیده
An approach to extract watersheds and watercourses, as well as their corresponding valleys and hills, from grid DTMs and digital images with subpixel accuracy is proposed. The critical points of the terrain, which are essential as the starting points for the construction of these separatrices, are extracted efficiently with subpixel accuracy by a linear-filter-based approach. The separatrices are extracted by integrating their defining differential equation. Finally, the hills and valleys are constructed by an efficient graph search algorithm. Examples show the quality of the results that can be achieved with the proposed approach.
منابع مشابه
Subpixel-Precise Extraction of Watersheds
An approach to extract watersheds and watercourses, as well as their corresponding valleys and hills, from images with subpixel precision is proposed. The critical points of the terrain are essential as the starting points for the construction of these separatrices. They are extracted efficiently with subpixel precision using an approach based on derivatives of Gaussian filters. The separatrice...
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