Synopsis
		sfdepth2time < in.rsf velocity=velocity.rsf > out.rsf nt= dt= t0= slow=n eps=0.01

Transforms function of z to function of

tau = Integral[2/v[x,n],{n,0,z}]

Parameters
		float dt= Time sampling (default is d1)   float eps=0.01 smoothness parameter   int nt= Number of points in time (default is n1)   bool slow=n [y/n] y: slowness, n: velocity   float t0= Time origin (default is 0)   file velocity= auxiliary input file name