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ImageImport

vtk-examples/Cxx/Images/ImageImport


Question

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Code

ImageImport.cxx

#include <vtkImageActor.h>
#include <vtkImageData.h>
#include <vtkImageImport.h>
#include <vtkInteractorStyleImage.h>
#include <vtkNamedColors.h>
#include <vtkNew.h>
#include <vtkRenderWindow.h>
#include <vtkRenderWindowInteractor.h>
#include <vtkRenderer.h>
#include <vtkXMLImageDataWriter.h>

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

  // Create a c-style image
  constexpr int width = 4;
  constexpr int height = 4;

  unsigned char cImage[width * height];
  unsigned char value = 0;
  for (unsigned int row = 0; row < height; ++row)
  {
    for (unsigned int col = 0; col < width; ++col)
    {
      cImage[row * width + col] = value;
      value += 10;
    }
  }

  // Convert the c-style image to a vtkImageData
  vtkNew<vtkImageImport> imageImport;
  imageImport->SetDataSpacing(1, 1, 1);
  imageImport->SetDataOrigin(0, 0, 0);
  imageImport->SetWholeExtent(0, width - 1, 0, height - 1, 0, 0);
  imageImport->SetDataExtentToWholeExtent();
  imageImport->SetDataScalarTypeToUnsignedChar();
  imageImport->SetNumberOfScalarComponents(1);
  imageImport->SetImportVoidPointer(cImage);
  imageImport->Update();

  // Create an actor
  vtkNew<vtkImageActor> actor;
  actor->SetInputData(imageImport->GetOutput());

  // Setup renderer
  vtkNew<vtkRenderer> renderer;
  renderer->AddActor(actor);
  renderer->ResetCamera();
  renderer->SetBackground(colors->GetColor3d("SaddleBrown").GetData());

  // Setup render window
  vtkNew<vtkRenderWindow> renderWindow;
  renderWindow->AddRenderer(renderer);
  renderWindow->SetWindowName("ImageImport");

  // Setup render window interactor
  vtkNew<vtkRenderWindowInteractor> renderWindowInteractor;
  vtkNew<vtkInteractorStyleImage> style;

  renderWindowInteractor->SetInteractorStyle(style);

  // Render and start interaction
  renderWindowInteractor->SetRenderWindow(renderWindow);
  renderWindow->Render();
  renderWindowInteractor->Initialize();

  renderWindowInteractor->Start();

  return EXIT_SUCCESS;
}

CMakeLists.txt

cmake_minimum_required(VERSION 3.3 FATAL_ERROR)

project(ImageImport)

find_package(VTK COMPONENTS 
  vtkCommonColor
  vtkCommonCore
  vtkCommonDataModel
  vtkIOImage
  vtkIOXML
  vtkInteractionStyle
  vtkRenderingContextOpenGL2
  vtkRenderingCore
  vtkRenderingFreeType
  vtkRenderingGL2PSOpenGL2
  vtkRenderingOpenGL2
  QUIET
)

if (NOT VTK_FOUND)
  message("Skipping ImageImport: ${VTK_NOT_FOUND_MESSAGE}")
  return ()
endif()
message (STATUS "VTK_VERSION: ${VTK_VERSION}")
if (VTK_VERSION VERSION_LESS "8.90.0")
  # old system
  include(${VTK_USE_FILE})
  add_executable(ImageImport MACOSX_BUNDLE ImageImport.cxx )
  target_link_libraries(ImageImport PRIVATE ${VTK_LIBRARIES})
else ()
  # include all components
  add_executable(ImageImport MACOSX_BUNDLE ImageImport.cxx )
  target_link_libraries(ImageImport PRIVATE ${VTK_LIBRARIES})
  # vtk_module_autoinit is needed
  vtk_module_autoinit(
    TARGETS ImageImport
    MODULES ${VTK_LIBRARIES}
    )
endif ()

Download and Build ImageImport

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

cd ImageImport/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:

./ImageImport

WINDOWS USERS

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