Synopsis
		sffftxcor < Fa.rsf ref=Fb.rsf > Fc.rsf verb=n nt=1 ot=0.0 dt=1.0

Fourier domain cross-correlation
Paul Sava
Copyright (C) 2022 Colorado School of Mines

Parameters
		float dt=1.0   int nt=1   float ot=0.0   file ref= auxiliary input file name   bool verb=n [y/n] verbosity