VTK/Examples/Cxx/Images/ImageExport

ImageExport.cxx

#include <vtkImageData.h>
#include <vtkImageExport.h>
#include <vtkSmartPointer.h>
#include <vtkVersion.h>

int main(int, char *[])
{   
  // Create an image data
  vtkSmartPointer<vtkImageData> imageData = 
    vtkSmartPointer<vtkImageData>::New();
 
  // Specify the size of the image data
  int dims[3] = {2,3,1};

  imageData->SetDimensions(dims[0], dims[1], dims[2]);
#if VTK_MAJOR_VERSION <= 5
  imageData->SetNumberOfScalarComponents(1);
  imageData->SetScalarTypeToUnsignedChar();
#else
  imageData->AllocateScalars(VTK_UNSIGNED_CHAR,1);
#endif

  unsigned char value = 0;
  for(int row = 0; row < dims[0]; ++row)
    {
    for(int col = 0; col < dims[1]; ++col)
      {
      unsigned char* pixel =
        static_cast<unsigned char*>(imageData->GetScalarPointer(row, col, 0));
      pixel[0] = value;
      value += 10;
      }
    }

  // Create the c-style image to convert the VTK image to
  unsigned char *cImage = new unsigned char[dims[0]*dims[1]*dims[2]];

  vtkSmartPointer<vtkImageExport> exporter =
    vtkSmartPointer<vtkImageExport>::New();
#if VTK_MAJOR_VERSION <= 5
  exporter->SetInput(imageData);
#else
  exporter->SetInputData(imageData);
#endif
  exporter->ImageLowerLeftOn();
  exporter->Update();
  exporter->Export(cImage);

  // Output the raw c-style image
  for(int row = 0; row < dims[0]; ++row)
    {
    for(int col = 0; col < dims[1]; ++col)
      {
      std::cout << static_cast<int>(cImage[col * dims[0] + row]) << " ";
      }
    std::cout << std::endl;
    }
  delete [] cImage;

  return EXIT_SUCCESS;
}

Please try the new VTKExamples website.

CMakeLists.txt

cmake_minimum_required(VERSION 2.8)

PROJECT(ImageExport)

find_package(VTK REQUIRED)
include(${VTK_USE_FILE})

add_executable(ImageExport MACOSX_BUNDLE ImageExport.cxx)

if(VTK_LIBRARIES)
  target_link_libraries(ImageExport ${VTK_LIBRARIES})
else()
  target_link_libraries(ImageExport vtkHybrid vtkWidgets)
endif()

Download and Build ImageExport

Click here to download ImageExport. and its CMakeLists.txt file.

Once the tarball ImageExport.tar has been downloaded and extracted,

cd ImageExport/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:

./ImageExport

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