Add vtkImageConnectivityFilter

This is the vtkImageData equivalent of vtkPolyDataConnectivityFilter.
It performs connectivity checks on points with values within a specific
scalar range (by default, it checks all points with values > 0).  Its
output is a label image, where each connected region is assigned an
integer label value.  Unlabeled points are assigned a value of zero.
1 job for image-connectivity-filter
Status Job ID Name Coverage
  External
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