I'm trying to create a texture mask for a game map, and need to select the cliffs on my terrain. How can I select the areas where the pixel value is substantially different from adjacent pixels by a certain amount?
Without a sample, difficult to give a good idea. Possible solution:
- Duplicate the layer
- Set the top to "difference" mode
- Start the "Median blur" filter, when its radius becomes close to the "thickness" of the cliffs, cliffs will appear over a ver dark background. Make a selection from the adequate R/G/B channel (or create a new layer and massage it first (desaturation, contrast...)