[vtkusers] CT Lung Segmentation: Extract Outer Contours

[frederic.salvador at epfl.ch]

Hi Siqi,

Thanks a lot for your propositions.

I finally adopted the following algo:
    - ConnectedThresholdImageFilter to fill the holes in the lung volume,
    - Morphological operators to fill the cavities (= holes with a  
contact with the outer surface of the lung volume).

Best regards

Fred