VTK/Examples/Cxx/Images/Blending2DImagesWithDifferentColorMaps

#include <vtkSmartPointer.h>
 
#include <vtkActor.h>
#include <vtkDataSet.h>
#include <vtkDataSetMapper.h>
#include <vtkImageBlend.h>
#include <vtkImageData.h>
#include <vtkImageMapToColors.h>
#include <vtkJPEGReader.h>
#include <vtkLookupTable.h>
#include <vtkRenderWindow.h>
#include <vtkRenderWindowInteractor.h>
#include <vtkRenderer.h>
 
int main(int argc, char *argv[]) 
{
  // Parse input arguments
  if ( argc != 3 )
    {
    std::cerr << "Usage: " << argv[0]
              << " Input1Filename Input2Filename" << std::endl;
    return EXIT_FAILURE;
    }
 
  vtkSmartPointer<vtkLookupTable> imgFirstColorMap = 
    vtkSmartPointer<vtkLookupTable>::New(); // hot color map
  imgFirstColorMap->SetRange( 0.0, 255.0 );
  imgFirstColorMap->SetHueRange( 0.0, 0.1 );
  imgFirstColorMap->SetValueRange( 0.4, 0.8 );
  imgFirstColorMap->Build();
 
  vtkSmartPointer<vtkLookupTable> imgSecondColorMap = 
      vtkSmartPointer<vtkLookupTable>::New(); // cold color map
  imgSecondColorMap->SetRange( 0.0, 255.0 );
  imgSecondColorMap->SetHueRange( 0.67, 0.68 );
  imgSecondColorMap->SetValueRange( 0.4, 0.8 );
  imgSecondColorMap->Build();
 
  vtkSmartPointer<vtkJPEGReader> imgReader = 
      vtkSmartPointer<vtkJPEGReader>::New();
  imgReader->SetFileName( argv[1] );
 
  vtkSmartPointer<vtkJPEGReader> imgReaderMoving = 
      vtkSmartPointer<vtkJPEGReader>::New();
  imgReaderMoving->SetFileName( argv[2] );
 
  vtkSmartPointer<vtkImageMapToColors> firstColorMapper = 
      vtkSmartPointer<vtkImageMapToColors>::New();
  firstColorMapper->SetInputConnection( imgReader->GetOutputPort() );
  firstColorMapper->SetLookupTable( imgFirstColorMap );
 
  vtkSmartPointer<vtkImageMapToColors> secondColorMapper = 
      vtkSmartPointer<vtkImageMapToColors>::New();
  secondColorMapper->SetInputConnection( imgReaderMoving->GetOutputPort() );
  secondColorMapper->SetLookupTable( imgSecondColorMap );
 
  vtkSmartPointer<vtkImageBlend> imgBlender = 
      vtkSmartPointer<vtkImageBlend>::New();
  imgBlender->SetOpacity( 0, 0.5 );
  imgBlender->SetOpacity( 1, 0.5 );
  imgBlender->AddInputConnection( firstColorMapper->GetOutputPort() );
  imgBlender->AddInputConnection( secondColorMapper->GetOutputPort() );
 
  vtkSmartPointer<vtkDataSetMapper> imgDataSetMapper = 
      vtkSmartPointer<vtkDataSetMapper>::New();
  imgDataSetMapper->SetInputConnection(imgBlender->GetOutputPort());
 
  vtkSmartPointer<vtkActor> imgActor = 
      vtkSmartPointer<vtkActor>::New();
  imgActor->SetMapper( imgDataSetMapper );
 
  vtkSmartPointer<vtkRenderer> imgRenderer = 
      vtkSmartPointer<vtkRenderer>::New();
  imgRenderer->AddActor( imgActor );
 
  vtkSmartPointer<vtkRenderWindow> imgRenderWindow = 
      vtkSmartPointer<vtkRenderWindow>::New();
  imgRenderWindow->AddRenderer( imgRenderer );
 
  vtkSmartPointer<vtkRenderWindowInteractor> imgInteractor = 
      vtkSmartPointer<vtkRenderWindowInteractor>::New();
  imgInteractor->SetRenderWindow( imgRenderWindow );
  imgInteractor->Initialize();
  imgInteractor->Start();
 
  return EXIT_SUCCESS;
}