[-h] [-v] [< domain file > [< grey file >]]
      Track a boundary up and down from the defined planes in
      the given domain using the poor-mans snake as in paint.
      Note it is assumed that the input objects are 3D and have
      appropriately matching planes etc.
      Options are:
      -r#       range - seach distance along perps. (def 5)
      -s#       spacing - spacing between perps. (def 5)
      -S#       size - side of image match square=(2S+1) (def S=4)
      -a#       angle cost parameter (def 0.0)
      -c#       curvature cost parameter (def 0.1)
      -d#       distance cost parameter (def 0.5)
      -D#       number of planes to track in down direction (def 1)
      -U#       number of planes to track in up direction (def 1)
      -h       help - prints this usage message
      -v       verbose operation