In some embodiments, {HEAD ~ synthesized pixels} that do not correspond to {TAIL ~ a body part} may be given a different type of index 
In some embodiments , { HEAD ~ synthesized pixels } that do not correspond to { TAIL ~ a body part } may be given a different type of index
OTH OTH OTH OTH HEAD HEAD HEAD HEAD HEAD HEAD OTH OTH REL REL REL TAIL TAIL TAIL TAIL TAIL TAIL TAIL OTH OTH OTH OTH OTH OTH OTH OTH