 determining, by the motion coordinate calculator, whether {HEAD ~ or not an X axis motion vector} corresponding to the calculated X axis motion has {TAIL ~ a value} of zero 
determining , by the motion coordinate calculator , whether { HEAD ~ or not an X axis motion vector } corresponding to the calculated X axis motion has { TAIL ~ a value } of zero
OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH HEAD HEAD HEAD HEAD HEAD HEAD HEAD HEAD HEAD HEAD HEAD OTH OTH OTH OTH OTH OTH OTH OTH TAIL TAIL TAIL TAIL TAIL TAIL OTH OTH