Synopsis
		sfffdb1 < in.rsf vel=vel.rsf > out.rsf opt=y try=n dt= nt= nb=20 v0=0 abc=0

Parameters
		int abc=0 absorbing boundary condition 1: cos 0: exp   float dt=   int nb=20   int nt=   bool opt=y [y/n]   bool try=n [y/n]   int v0=0   file vel= auxiliary input file name