determining means for determining whether each pixel signal read by the image reading means represents a white pixel and for generating {HEAD ~ a white pixel signal} representing {TAIL ~ the white pixel} 
representing
determining means for determining whether each pixel signal read by the image reading means represents a white pixel and for generating { HEAD ~ a white pixel signal } representing { TAIL ~ the white pixel }
OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH HEAD HEAD HEAD HEAD HEAD HEAD HEAD HEAD REL TAIL TAIL TAIL TAIL TAIL TAIL TAIL