ITK/Examples/ImageProcessing/TileImageFilter SideBySide

This example reads in two 2D images and outputs a 2D image of the two inputs side by side.

TileImageFilter_SideBySide.cxx

<source lang="cpp">

1. include "itkImage.h"
2. include "itkImageFileReader.h"
3. include "itkImageFileWriter.h"
4. include "itkTileImageFilter.h"

int main(int argc, char *argv[] ) {

 // Verify arguments
 if (argc < 4)
   {
   std::cerr << "Usage: " << std::endl;
   std::cerr << argv[0] << "input1 input2 output" << std::endl;
   return EXIT_FAILURE;
   }

 // Parse arguments
 std::string input1FileName = argv[1];
 std::string input2FileName = argv[2];
 std::string outputFileName = argv[3];

 // Output arguments
 std::cout << "input1FileName " << input1FileName << std::endl;
 std::cout << "input2FileName " << input2FileName << std::endl;;
 std::cout << "outputFileName " << outputFileName << std::endl;;
 
 typedef itk::Image< unsigned char, 2>   ImageType;

 // Read images
 typedef itk::ImageFileReader< ImageType > ImageReaderType ;
 ImageReaderType::Pointer reader1 = ImageReaderType::New();
 reader1->SetFileName(input1FileName);
 reader1->Update();

 ImageReaderType::Pointer reader2 = ImageReaderType::New();
 reader2->SetFileName(input2FileName);
 reader2->Update();

 // Tile the images side-by-side
 typedef itk::TileImageFilter< ImageType, ImageType > TileFilterType;

 TileFilterType::Pointer tileFilter = TileFilterType::New();

 itk::FixedArray< unsigned int, 2 > layout;

 layout[0] = 2;
 layout[1] = 0;

 tileFilter->SetLayout( layout );

 tileFilter->SetInput(0, reader1->GetOutput());
 tileFilter->SetInput(1, reader2->GetOutput());

 // Set the value of output pixels which are created by mismatched size inputu images.
 // If the two images are the same height, this will not be used.
 unsigned char fillerValue = 128;
 tileFilter->SetDefaultPixelValue( fillerValue );

 tileFilter->Update();

 // Write the output image
 typedef itk::ImageFileWriter< ImageType > WriterType;
 WriterType::Pointer writer = WriterType::New();
 writer->SetInput( tileFilter->GetOutput() );
 writer->SetFileName( outputFileName );
 writer->Update();

 return EXIT_SUCCESS;

}

</source>

CMakeLists.txt

<syntaxhighlight lang="cmake"> cmake_minimum_required(VERSION 3.9.5)

project(TileImageFilter_SideBySide)

find_package(ITK REQUIRED) include(${ITK_USE_FILE}) if (ITKVtkGlue_LOADED)

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

endif()

add_executable(TileImageFilter_SideBySide MACOSX_BUNDLE TileImageFilter_SideBySide.cxx)

if( "${ITK_VERSION_MAJOR}" LESS 4 )

 target_link_libraries(TileImageFilter_SideBySide ITKReview ${ITK_LIBRARIES})

else( "${ITK_VERSION_MAJOR}" LESS 4 )

 target_link_libraries(TileImageFilter_SideBySide ${ITK_LIBRARIES})

endif( "${ITK_VERSION_MAJOR}" LESS 4 )

</syntaxhighlight>

Download and Build TileImageFilter_SideBySide

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

cd TileImageFilter_SideBySide/build

• If ITK is installed:

cmake ..

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

cmake -DITK_DIR:PATH=/home/me/itk_build ..

Build the project:

make

and run it:

./TileImageFilter_SideBySide

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

Building All of the Examples

Many of the examples in the ITK Wiki Examples Collection require VTK. You can build all of the the examples by following these instructions. If you are a new VTK user, you may want to try the Superbuild which will build a proper ITK and VTK.

ItkVtkGlue

ITK >= 4

For examples that use QuickView (which depends on VTK), you must have built ITK with Module_ITKVtkGlue=ON.

ITK < 4

Some of the ITK Examples require VTK to display the images. If you download the entire ITK Wiki Examples Collection, the ItkVtkGlue directory will be included and configured. If you wish to just build a few examples, then you will need to download ItkVtkGlue and build it. When you run cmake it will ask you to specify the location of the ItkVtkGlue binary directory.