Synopsis
		sfsimilarity < in.rsf > out.rsf other=other.rsf verb=y niter=20 eps=0.0f rect#=(1,1,...)

September 2015 program of the month:
http://ahay.org/blog/2015/09/14/program-of-the-month-sfsimilarity/

Parameters
		float eps=0.0f regularization   int niter=20 maximum number of iterations   file other= auxiliary input file name   int rect#=(1,1,...) smoothing radius on #-th axis   bool verb=y [y/n] verbosity