# Show the constant kernel.  Smooth an impulse function.

package require vtk

vtkImageCanvasSource2D s1
s1 SetScalarTypeToFloat
s1 SetExtent 0 255 0 255 0 0
s1 SetDrawColor 0
s1 FillBox 0 255 0 255
s1 SetDrawColor 1.0
s1 FillBox 75 175 75 175

vtkImageConvolve convolve
convolve SetInputConnection [s1 GetOutputPort]
convolve SetKernel5x5 1 1 1 1 1  5 4 3 2 1  5 4 3 2 1  5 4 3 2 1  1 1 1 1 1 

vtkImageViewer viewer
viewer SetInputConnection [convolve GetOutputPort]
viewer SetColorWindow 18
viewer SetColorLevel 9

viewer Render