The system further includes a programmed computer that determines whether {HEAD ~ each pixel} is a constant area pixel or {TAIL ~ an edge area pixel} 
is
The system further includes a programmed computer that determines whether { HEAD ~ each pixel } is a constant area pixel or { TAIL ~ an edge area pixel }
OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH HEAD HEAD HEAD HEAD HEAD HEAD REL OTH OTH OTH OTH OTH TAIL TAIL TAIL TAIL TAIL TAIL TAIL TAIL