Edge-detect in a somewhat different way to most edge-detection algorithms, on this page you select the brightness levels you want to act as edge-detection breaks, and the line colour at each brightness break, plus the line thickness. The greater the difference between two brightnesses at an ‘edge’, the more opaque the resulting line will be; edges with a small amount of brightness difference will be quite translucent.

So far as I know no other edge detection software works in this way, and how useful it is very much depends on which brightness level breaks are chosen. Experimental.