Fig. 6.

Example of watershed transformation for color pattern extraction in fire salamanders (Salamandra salamandra). (A.) Original image. (B.) Image gradient transformed to a reference shape using landmarks. (C.) Transformed image with watershed lines highlighted. (D.) Extracted patterns using the watershed lines. (E.) Heatmap of orange patterns extracted from ten male fire salamanders. Areas outside the red box were masked. Images were obtained with permission from Balogová & Uhrin (2015).