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ImageCityBlockDistance

Repository source: ImageCityBlockDistance

Description

Compute the Manhattan distance from every point to every black point in a binary image.

Question

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

Code

ImageCityBlockDistance.cxx

#include <vtkImageActor.h>
#include <vtkImageCast.h>
#include <vtkImageCityBlockDistance.h>
#include <vtkImageMapper3D.h>
#include <vtkImageReader2.h>
#include <vtkImageReader2Factory.h>
#include <vtkInteractorStyleImage.h>
#include <vtkNamedColors.h>
#include <vtkNew.h>
#include <vtkRenderWindow.h>
#include <vtkRenderWindowInteractor.h>
#include <vtkRenderer.h>
#include <vtkSmartPointer.h>

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

  // Verify command line arguments.
  if (argc < 2)
  {
    std::cout << "Usage: " << argv[0] << " BinaryImage e.g. Yinyang.jpg"
              << std::endl;
    return EXIT_FAILURE;
  }

  // Read file.
  vtkNew<vtkImageReader2Factory> readerFactory;
  vtkSmartPointer<vtkImageReader2> reader;
  reader.TakeReference(readerFactory->CreateImageReader2(argv[1]));
  reader->SetFileName(argv[1]);

  vtkNew<vtkImageCast> castFilter;
  castFilter->SetOutputScalarTypeToShort();
  castFilter->SetInputConnection(reader->GetOutputPort());

  vtkNew<vtkImageCityBlockDistance> cityBlockDistanceFilter;
  cityBlockDistanceFilter->SetInputConnection(castFilter->GetOutputPort());
  cityBlockDistanceFilter->SetDimensionality(2);
  cityBlockDistanceFilter->Update();

  // Create actors.
  vtkNew<vtkImageCast> inputCastFilter;
  inputCastFilter->SetOutputScalarTypeToUnsignedChar();
  inputCastFilter->SetInputConnection(reader->GetOutputPort());

  vtkNew<vtkImageActor> inputActor;
  inputActor->GetMapper()->SetInputConnection(inputCastFilter->GetOutputPort());

  vtkNew<vtkImageCast> distanceCastFilter;
  distanceCastFilter->SetOutputScalarTypeToUnsignedChar();
  distanceCastFilter->SetInputConnection(
      cityBlockDistanceFilter->GetOutputPort());

  vtkNew<vtkImageActor> distanceActor;
  distanceActor->GetMapper()->SetInputConnection(
      distanceCastFilter->GetOutputPort());

  // Define viewport ranges.
  // (xmin, ymin, xmax, ymax)
  double inputViewport[4] = {0.0, 0.0, 0.5, 1.0};
  double distanceViewport[4] = {0.5, 0.0, 1.0, 1.0};

  // Setup renderers.
  vtkNew<vtkRenderer> inputRenderer;
  inputRenderer->SetViewport(inputViewport);
  inputRenderer->AddActor(inputActor);
  inputRenderer->ResetCamera();
  inputRenderer->SetBackground(colors->GetColor3d("CornflowerBlue").GetData());

  vtkNew<vtkRenderer> distanceRenderer;
  distanceRenderer->SetViewport(distanceViewport);
  distanceRenderer->AddActor(distanceActor);
  distanceRenderer->ResetCamera();
  distanceRenderer->SetBackground(colors->GetColor3d("LightSkyBlue").GetData());

  // Setup render window.
  vtkNew<vtkRenderWindow> renderWindow;
  renderWindow->SetSize(600, 300);
  renderWindow->AddRenderer(inputRenderer);
  renderWindow->AddRenderer(distanceRenderer);
  renderWindow->SetWindowName("ImageCityBlockDistance");

  // 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 3.12 FATAL_ERROR)

project(ImageCityBlockDistance)

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

if (NOT VTK_FOUND)
  message(FATAL_ERROR "ImageCityBlockDistance: 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(ImageCityBlockDistance MACOSX_BUNDLE ImageCityBlockDistance.cxx )
  target_link_libraries(ImageCityBlockDistance PRIVATE ${VTK_LIBRARIES}
)
# vtk_module_autoinit is needed
vtk_module_autoinit(
  TARGETS ImageCityBlockDistance
  MODULES ${VTK_LIBRARIES}
)

Download and Build ImageCityBlockDistance

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

cd ImageCityBlockDistance/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:

./ImageCityBlockDistance

WINDOWS USERS

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