package require vtk

# A script to test the threshold filter.
# Values above 2000 are set to 255.
# Values below 2000 are set to 0.


# Image pipeline

vtkPNGReader reader
reader SetFileName "$VTK_DATA_ROOT/Data/fullhead15.png"

vtkImageCast cast
cast SetOutputScalarTypeToShort
cast SetInputConnection [reader GetOutputPort]

vtkImageThreshold thresh
thresh SetInputConnection [cast GetOutputPort]
thresh ThresholdByUpper 2000.0
thresh SetInValue 0
thresh SetOutValue 200
thresh ReleaseDataFlagOff

vtkImageCityBlockDistance dist
dist SetDimensionality 2
dist SetInputConnection [thresh GetOutputPort]

vtkImageViewer viewer
viewer SetInputConnection [dist GetOutputPort]
viewer SetColorWindow 117
viewer SetColorLevel 43

viewer Render