A watershed algorithm for triangulated terrains
نویسنده
چکیده
We study the problem of automatically identifying watershed boundaries from digital elevation data. Nelson et al. have a vector-based algorithm to solve this problem, but their approach cannot guarantee that each watershed is a single polygon because of the modeling assumptions. We propose a vector-based algorithm that is provably consistent with its modeling assumptions and that guarantees one polygon per watershed. Our algorithm nds the watershed boundaries for local minima in the terrain in (n) worst-case time.
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