Synopsis
		sfconstpermh1 < data.rsf > image.rsf mig=n snap=0 nz= dz= nt= dt= nh= dh= v=

Parameters
		float dh= offset sampling (if modeling)   float dt= time sampling (if modeling)   float dz= depth sampling (if migration)   bool mig=n [y/n] if n, modeling; if y, migration   int nh= offset samples (if modeling)   int nt= time samples (if modeling)   int nz= depth samples (if migration)   int snap=0 interval for snapshots   float v= velocity