old_contents: from numpy import arange
  from scipy.ndimage.interpolation import shift
  
  from registration import CrossCorr
  
  reference = arange(9).reshape(3, 3)
  deltas = [[1, 0], [0, 1]]
  shifted = [shift(reference, delta, mode='wrap', order=0) for delta in deltas]
  
  register = CrossCorr()
  model = register.fit(shifted, reference=reference)
  
  print model.transformations
new_contents: from numpy import arange
  from scipy.ndimage.interpolation import shift
  
  from registration import CrossCorr
  
  reference = arange(9).reshape(3, 3)
  deltas = [[1, 0], [0, 1]]
  shifted = [shift(reference, delta, mode='wrap', order=0) for delta in deltas]
  
  register = CrossCorr()
  model = register.fit(shifted, reference=reference)
  
  print 'real deltas: '
  print deltas
  
  print ''
  
  print 'estimated deletas: '
  print model.toarray().tolist()
  
subject: improve example