Evaluation of the Threshold for an Improved Surface Water Extraction Index Using Optical Remote Sensing Data

Figure 10

Test case results of the AWEI threshold improvement to detect lake surface water (water and nonwater class) in Toba lake: (a) map references were obtained based on the on-screen visual digitization of Landsat 8 imagery from 2019; (b) classification based on the normal threshold; (c) classification based on the equal interval threshold; (d) classification based on the quantile threshold; (e) classification based on the geometrical interval threshold; and (f) classification based on the natural break threshold.

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