The reference data is hexadecimal data F0 representing {TAIL ~ the density} of a black dot, while hexadecimal data FF represents the density of {HEAD ~ a white dot} 
The reference data is hexadecimal data F0 representing { TAIL ~ the density } of a black dot , while hexadecimal data FF represents the density of { HEAD ~ a white dot }
OTH OTH OTH OTH OTH OTH OTH OTH TAIL TAIL TAIL TAIL TAIL TAIL OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH HEAD HEAD HEAD HEAD HEAD HEAD HEAD