Reinventing the wheel but, you know, why not...
Input image:-
Outputs:-
Highlighting intensity: 1
Highlighting intensity: 2
Highlighting intensity: 4
Highlighting intensity: 6
Highlighting intensity: 8
./edge <path/input_image.extension> <path/output_image.extension> <highlighting intensity[normal:1]>
Example:-
./edge catto.png catto_weird.png 6