Program sfpick | Automatic picking from semblance-like panels.
[SYNOPSIS]
sfpick < scn.rsf > pik.rsf vel0=o2 niter=100 an=1. gate=3 smooth=y norm=n back=n rect#=(1,1,...) rect1=1 rect2=1 ...
[COMMENTS]
rectN defines the size of the smoothing stencil in N-th dimension.

Theory in Appendix B of:
S. Fomel, 2009,
Velocity analysis using AB semblance: Geophysical Prospecting, v. 57, 311-321.
Reproducible version in RSFSRC/book/tccs/avo
http://ahay.org/RSF/book/tccs/avo/paper_html/

August 2012 program of the month:
http://ahay.org/blog/2012/08/01/program-of-the-month-sfpick/

[PARAMETERS]
float   | an | =1. |   | 	axes anisotropy 
bool    | back | =n |  [y/n] | 	if run backward 
int     | gate | =3 |   | 	picking gate 
int     | niter | =100 |   | 	number of iterations 
bool    | norm | =n |  [y/n] | 	if apply normalization (0.~1.) 
int     | rect# | =(1,1,...) |   | 	smoothing radius on #-th axis 
bool    | smooth | =y |  [y/n] | 	if apply smoothing 
float   | vel0 | =o2 |   | 	surface velocity 
[DIRECTORY]
user/fomels
