{TAIL ~ a first set} of zero coefficients extending along a direction traversing said filter through a center position to form {HEAD ~ a first side} and a second side 
{ TAIL ~ a first set } of zero coefficients extending along a direction traversing said filter through a center position to form { HEAD ~ a first side } and a second side
TAIL TAIL TAIL TAIL TAIL TAIL TAIL OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH HEAD HEAD HEAD HEAD HEAD HEAD HEAD OTH OTH OTH OTH