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3.5.4. Trying Different Volumes of Interest and Sampling Rates This is the same code from section 3.5.3. Try some different sampling rates and volumes of interest. Remember, it is only possible to use integers, so there will be some factor of difference from one sampling rate to another. Farther below are three examples of different combinations.
import Tkinter import vtk from vtk.tk.vtkTkRenderWindowInteractor import vtkTkRenderWindowInteractor # Prepare to read the file readerVolume = vtk.vtkImageReader() readerVolume.SetDataScalarType( vtk.VTK_UNSIGNED_SHORT ) readerVolume.SetFileDimensionality( 3 ) readerVolume.SetDataExtent ( 0,255, 0,255, 0,576) readerVolume.SetDataSpacing( 1,1,1 ) readerVolume.SetNumberOfScalarComponents( 1 ) readerVolume.SetDataByteOrderToBigEndian() readerVolume.SetFileName( "./Female.raw" ) # Extract the region of interest voiHead = vtk.vtkExtractVOI() voiHead.SetInput( readerVolume.GetOutput() ) voiHead.SetVOI( 0,255, 60,255, 0,100 ) voiHead.SetSampleRate( 1,1,1 ) #### BONE #contourBone = vtk.vtkContourFilter() contourBone = vtk.vtkMarchingCubes() contourBone.SetInput( voiVolumeSection.GetOutput() ) contourBone.ComputeNormalsOn() contourBone.SetValue( 0, 1250 ) geoVolumeBone = vtk.vtkPVGeometryFilter() geoVolumeBone.SetInput( contourBone.GetOutput() ) geoBoneMapper = vtk.vtkPolyDataMapper() geoBoneMapper.SetInput( geoVolumeBone.GetOutput() ) geoBoneMapper.ScalarVisibilityOff() actorBone = vtk.vtkLODActor() actorBone.SetNumberOfCloudPoints( 1000000 ) actorBone.SetMapper( geoBoneMapper ) actorBone.GetProperty().SetColor( 1, 1, 1 ) ### SKIN #contourSkin = vtk.vtkContourFilter() contourSkin = vtk.vtkMarchingCubes() contourSkin.SetInput( voiVolumeSection.GetOutput() ) contourSkin.SetValue( 0, 760 ) contourSkin.ComputeNormalsOn() geoVolumeSkin= vtk.vtkPVGeometryFilter() geoVolumeSkin.SetInput( contourSkin.GetOutput() ) geoSkinMapper = vtk.vtkPolyDataMapper() geoSkinMapper.SetInput( geoVolumeSkin.GetOutput() ) geoSkinMapper.ScalarVisibilityOff() actorSkin = vtk.vtkLODActor() actorSkin.SetNumberOfCloudPoints( 1000000 ) actorSkin.SetMapper( geoSkinMapper ) actorSkin.GetProperty().SetColor( 1, 0.547237, 0.319073 ) actorSkin.GetProperty().SetOpacity( 0.3 ) # Create renderer ren = vtk.vtkRenderer() ren.SetBackground( 0.329412, 0.34902, 0.427451 ) #Paraview blue ren.AddActor(actorBone) ren.AddActor(actorSkin) # Create a window for the renderer of size 250x250 renWin = vtk.vtkRenderWindow() renWin.AddRenderer(ren) renWin.SetSize(250, 250) # Set an user interface interactor for the render window iren = vtk.vtkRenderWindowInteractor() iren.SetRenderWindow(renWin) # Start the initialization and rendering iren.Initialize() renWin.Render() iren.Start() Example 3.4: Code for experimenting with volume of interest and sampling rates
Sampling Rate: (1,1,1) Volume of Interest: (0,255, 60,255, 0,100)			Sampling Rate: (1,1,1) Volume of Interest: (0,255, 60,255, 476,576)	Sampling Rate: (1,1,1) Volume of Interest: (0,255, 60,255, 0,100)
Sampling Rate: (2,2,1) Volume of Interest: (0,255, 60,255, 0,100)			Sampling Rate: (3,3,1) Volume of Interest: (0,255, 60,255, 476,576)	Sampling Rate: (4,4,1) Volume of Interest: (0,255, 60,255, 0,100)
Figure 3.4: Renderings of various volumes of interest using different sampling rates.
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