            contour = vtkDiscreteMarchingCubes()
    else:
        contour = vtkDiscreteMarchingCubes()
    contour.SetInputConnection(voi.GetOutputPort())
    # contour.ComputeNormalsOn()

    print('Doing label', index)

--
            discrete_cubes = vtkDiscreteMarchingCubes()
    else:
        using_marching_cubes = True
        discrete_cubes = vtkDiscreteMarchingCubes()
    smoother = vtkWindowedSincPolyDataFilter()
    selector = vtkThreshold()
    scalars_off = vtkMaskFields()
    geometry = vtkGeometryFilter()
    writer = vtkXMLPolyDataWriter()
--
            discrete = vtkDiscreteMarchingCubes()
    else:
        discrete = vtkDiscreteMarchingCubes()
    discrete.SetInputData(blob)
    discrete.GenerateValues(n, 1, n)

    lut = make_colors(n)

--
    discrete = vtkDiscreteMarchingCubes()
    discrete.SetInputData(blob)
    discrete.GenerateValues(n, 1, n)

    smoothing_iterations = 15
    pass_band = 0.001
