The method 19 wherein the function is {HEAD ~ a logical function} including {TAIL ~ the minimum} or maximum of the height and gray scale values 
including
The method 19 wherein the function is { HEAD ~ a logical function } including { TAIL ~ the minimum } or maximum of the height and gray scale values
OTH OTH OTH OTH OTH OTH OTH HEAD HEAD HEAD HEAD HEAD HEAD HEAD REL TAIL TAIL TAIL TAIL TAIL TAIL OTH OTH OTH OTH OTH OTH OTH OTH OTH