/**
 \defgroup ITKSignedDistanceFunction Module ITKSignedDistanceFunction 
 This module contains classes for calculating signed distance
images, i.e. images of the distance from a segmenting contour (the distance is
zero on the contour, negative inside the contour, and positive outside the
contour). 
 \par Dependencies:
 \li \ref ITKImageFunction 
 \dot 
 graph "ITKSignedDistanceFunction" { 
 "ITKSignedDistanceFunction" -- "ITKImageFunction"; 
 } 
 \enddot 
 */