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Colored2DImageFusion

vtk-examples/Cxx/Images/Colored2DImageFusion


Description

This example use the vtkImageBlend class for a simple fusion of two 2D images with different color maps for each of the images.

  • Contributed by: Tim Hutz

Question

If you have a question about this example, please use the VTK Discourse Forum

Code

Colored2DImageFusion.cxx

#include <vtkActor.h>
#include <vtkDataSetMapper.h>
#include <vtkImageBlend.h>
#include <vtkImageMapToColors.h>
#include <vtkImageReader2.h>
#include <vtkImageReader2Factory.h>
#include <vtkLookupTable.h>
#include <vtkNamedColors.h>
#include <vtkRenderWindow.h>
#include <vtkRenderWindowInteractor.h>
#include <vtkRenderer.h>
#include <vtkSmartPointer.h>

int main(int argc, char* argv[])
{
  vtkNew<vtkNamedColors> colors;

  // Parse input arguments.
  if (argc < 3)
  {
    std::cerr << "Usage: " << argv[0]
              << " Input1Filename Input2Filename e.g. Ox.jpg Gourds2.jpg"
              << std::endl;
    return EXIT_FAILURE;
  }

  vtkNew<vtkLookupTable> imgFirstColorMap;
  imgFirstColorMap->SetRange(0.0, 255.0);
  imgFirstColorMap->SetHueRange(0.0, 0.1);
  imgFirstColorMap->SetValueRange(0.4, 0.8);
  imgFirstColorMap->Build();

  vtkNew<vtkLookupTable> imgSecondColorMap;
  imgSecondColorMap->SetRange(0.0, 255.0);
  imgSecondColorMap->SetHueRange(0.67, 0.68);
  imgSecondColorMap->SetValueRange(0.4, 0.8);
  imgSecondColorMap->Build();

  vtkNew<vtkImageReader2Factory> readerFactory;
  vtkSmartPointer<vtkImageReader2> imgReader;
  imgReader.TakeReference(readerFactory->CreateImageReader2(argv[1]));
  imgReader->SetFileName(argv[1]);

  vtkSmartPointer<vtkImageReader2> imgReaderMoving;
  imgReaderMoving.TakeReference(readerFactory->CreateImageReader2(argv[2]));
  imgReaderMoving->SetFileName(argv[2]);

  vtkNew<vtkImageMapToColors> firstColorMapper;
  firstColorMapper->SetInputConnection(imgReader->GetOutputPort());
  firstColorMapper->SetLookupTable(imgFirstColorMap);

  vtkNew<vtkImageMapToColors> secondColorMapper;
  secondColorMapper->SetInputConnection(imgReaderMoving->GetOutputPort());
  secondColorMapper->SetLookupTable(imgSecondColorMap);

  vtkNew<vtkImageBlend> imgBlender;
  imgBlender->SetOpacity(0, 0.5);
  imgBlender->SetOpacity(1, 0.5);
  imgBlender->AddInputConnection(firstColorMapper->GetOutputPort());
  imgBlender->AddInputConnection(secondColorMapper->GetOutputPort());

  vtkNew<vtkDataSetMapper> imgDataSetMapper;
  imgDataSetMapper->SetInputConnection(imgBlender->GetOutputPort());

  vtkNew<vtkActor> imgActor;
  imgActor->SetMapper(imgDataSetMapper);

  vtkNew<vtkRenderer> imgRenderer;
  imgRenderer->AddActor(imgActor);
  imgRenderer->SetBackground(colors->GetColor3d("BurlyWood").GetData());

  vtkNew<vtkRenderWindow> imgRenderWindow;
  imgRenderWindow->AddRenderer(imgRenderer);
  imgRenderWindow->SetWindowName("Colored2DImageFusion");

  vtkNew<vtkRenderWindowInteractor> imgInteractor;
  imgInteractor->SetRenderWindow(imgRenderWindow);
  imgRenderWindow->Render();
  imgInteractor->Initialize();
  imgInteractor->Start();

  return EXIT_SUCCESS;
}

CMakeLists.txt

cmake_minimum_required(VERSION 3.12 FATAL_ERROR)

project(Colored2DImageFusion)

find_package(VTK COMPONENTS 
  CommonColor
  CommonCore
  IOImage
  ImagingCore
  InteractionStyle
  RenderingContextOpenGL2
  RenderingCore
  RenderingFreeType
  RenderingGL2PSOpenGL2
  RenderingOpenGL2
)

if (NOT VTK_FOUND)
  message(FATAL_ERROR "Colored2DImageFusion: Unable to find the VTK build folder.")
endif()

# Prevent a "command line is too long" failure in Windows.
set(CMAKE_NINJA_FORCE_RESPONSE_FILE "ON" CACHE BOOL "Force Ninja to use response files.")
add_executable(Colored2DImageFusion MACOSX_BUNDLE Colored2DImageFusion.cxx )
  target_link_libraries(Colored2DImageFusion PRIVATE ${VTK_LIBRARIES}
)
# vtk_module_autoinit is needed
vtk_module_autoinit(
  TARGETS Colored2DImageFusion
  MODULES ${VTK_LIBRARIES}
)

Download and Build Colored2DImageFusion

Click here to download Colored2DImageFusion and its CMakeLists.txt file. Once the tarball Colored2DImageFusion.tar has been downloaded and extracted,

cd Colored2DImageFusion/build

If VTK is installed:

cmake ..

If VTK is not installed but compiled on your system, you will need to specify the path to your VTK build:

cmake -DVTK_DIR:PATH=/home/me/vtk_build ..

Build the project:

make

and run it:

./Colored2DImageFusion

WINDOWS USERS

Be sure to add the VTK bin directory to your path. This will resolve the VTK dll's at run time.