Image edge detection

[ChrisIB]

Using edge detection is often used to 'look under the surface' of images.
With the heavyweight but free GIMP software (gimp.org) it is as simple as loading image then Filters, Edge-detect, Edge, Roberts
Tried it and whilst most produced the expected 'bolding' a few were interesting

 

[nivek]

GIMP is a most excellent open source software for images, editing, and creation...I have used it for years...

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