[vtkusers] Fw: Hi, question about vtkMapToWindowLevelColors

[Hui Zhang (James)]

Hi,

I encounter some problems in using vtkMapToWindowLevelColors, maybe a little confused how to use it. 

What I want to do is: I have a medical image data set (16 bits), and want to use this filter to do window level/width operation, it works well. Now I want to add some new features, for example, mark the CT value range of (500 - 700) to red, but keep other values to their default gray value. So how should I specify the this filter with LUT? Ex: window level/width can be specified to (400, 1000)

Additional, I donnot know how this filter process image map and window level/width operation. Do color mapping through LUT, then do window level /width modulation, or window level/width opeartion first, then mapping through LUT? or these two operations are integrated in the same LUT?

  m_ImageMap->SetInput( image );
  
  vtkLookupTable* lut = vtkLookupTable::New();

//////////////////////////////////////////////////////////////////   how to specify the codes in this section?

  lut->SetNumberOfTableValues(256);
  //lut->SetHueRange(0.0, 0.0);
  //lut->SetSaturationRange(0.0, 0.0);
  //lut->SetValueRange(0.0, 1.0);
  lut->Build();
  for (i = 240; i <= 255; i++)
  {
    lut->SetTableValue(i, ............... );
  }
  for (i = 0; i <= 240; i++)
  {
    lut->SetTableValue(i, .....................);
  }

//////////////////////////////////////////////////////////////////////////
  
  m_ImageMap->SetLookupTable(lut);

  m_ImageMap->SetLevel( level );
  m_ImageMap->SetWindow( width );
  
m_Actor->SetInput( m_ImageMap->GetOutput() );

Thanks a lot!!!

Hui Zhang
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