“…The black graph is correct for arc 1,3,4,6 but is wrong for arc 2,6,7. A simple "best of the arcs" (image 3) finds a correct answer where both graphs are correct (1,3,6,7), when the black one is wrong (2,5,7) and when the white one is wrong (4). However the crossroad between (2,4,5) is too extended (radius 9 pixels).…”