ImageGradientMagnitude
VTKExamples/Cxx/Images/ImageGradientMagnitude
Code¶
ImageGradientMagnitude.cxx
#include <vtkSmartPointer.h> #include <vtkImageData.h> #include <vtkImageMapper3D.h> #include <vtkImageGradientMagnitude.h> #include <vtkRenderWindow.h> #include <vtkRenderWindowInteractor.h> #include <vtkInteractorStyleImage.h> #include <vtkRenderer.h> #include <vtkJPEGReader.h> #include <vtkImageActor.h> #include <vtkImageEllipsoidSource.h> #include <vtkImageCast.h> int main(int, char *[]) { // Create an image vtkSmartPointer<vtkImageEllipsoidSource> source = vtkSmartPointer<vtkImageEllipsoidSource>::New(); source->SetWholeExtent(0, 20, 0, 20, 0, 0); source->SetCenter(10,10,0); source->SetRadius(3,4,0); source->Update(); vtkSmartPointer<vtkImageGradientMagnitude> gradientMagnitudeFilter = vtkSmartPointer<vtkImageGradientMagnitude>::New(); gradientMagnitudeFilter->SetInputConnection(source->GetOutputPort()); gradientMagnitudeFilter->Update(); vtkSmartPointer<vtkImageCast> gradientMagnitudeCastFilter = vtkSmartPointer<vtkImageCast>::New(); gradientMagnitudeCastFilter->SetInputConnection(gradientMagnitudeFilter->GetOutputPort()); gradientMagnitudeCastFilter->SetOutputScalarTypeToUnsignedChar(); gradientMagnitudeCastFilter->Update(); // Create actors vtkSmartPointer<vtkImageActor> originalActor = vtkSmartPointer<vtkImageActor>::New(); originalActor->GetMapper()->SetInputConnection(source->GetOutputPort()); vtkSmartPointer<vtkImageActor> gradientMagnitudeActor = vtkSmartPointer<vtkImageActor>::New(); gradientMagnitudeActor->GetMapper()->SetInputConnection( gradientMagnitudeCastFilter->GetOutputPort()); // Define viewport ranges // (xmin, ymin, xmax, ymax) double originalViewport[4] = {0.0, 0.0, 0.5, 1.0}; double gradientMagnitudeViewport[4] = {0.5, 0.0, 1.0, 1.0}; // Setup renderers vtkSmartPointer<vtkRenderer> originalRenderer = vtkSmartPointer<vtkRenderer>::New(); originalRenderer->SetViewport(originalViewport); originalRenderer->AddActor(originalActor); originalRenderer->ResetCamera(); originalRenderer->SetBackground(.4, .5, .6); vtkSmartPointer<vtkRenderer> gradientMagnitudeRenderer = vtkSmartPointer<vtkRenderer>::New(); gradientMagnitudeRenderer->SetViewport(gradientMagnitudeViewport); gradientMagnitudeRenderer->AddActor(gradientMagnitudeActor); gradientMagnitudeRenderer->ResetCamera(); gradientMagnitudeRenderer->SetBackground(.4, .5, .7); vtkSmartPointer<vtkRenderWindow> renderWindow = vtkSmartPointer<vtkRenderWindow>::New(); renderWindow->SetSize(600, 300); renderWindow->AddRenderer(originalRenderer); renderWindow->AddRenderer(gradientMagnitudeRenderer); vtkSmartPointer<vtkRenderWindowInteractor> renderWindowInteractor = vtkSmartPointer<vtkRenderWindowInteractor>::New(); vtkSmartPointer<vtkInteractorStyleImage> style = vtkSmartPointer<vtkInteractorStyleImage>::New(); renderWindowInteractor->SetInteractorStyle(style); renderWindowInteractor->SetRenderWindow(renderWindow); renderWindowInteractor->Initialize(); renderWindowInteractor->Start(); return EXIT_SUCCESS; }
CMakeLists.txt¶
cmake_minimum_required(VERSION 2.8) PROJECT(ImageGradientMagnitude) find_package(VTK REQUIRED) include(${VTK_USE_FILE}) add_executable(ImageGradientMagnitude MACOSX_BUNDLE ImageGradientMagnitude.cxx) target_link_libraries(ImageGradientMagnitude ${VTK_LIBRARIES})
Download and Build ImageGradientMagnitude¶
Danger
The generation of tar files has not been ported to the new VTKExamples. Some tarballs may be missing or out-of-date.
Click here to download ImageGradientMagnitude and its CMakeLists.txt file. Once the tarball ImageGradientMagnitude.tar has been downloaded and extracted,
cd ImageGradientMagnitude/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:
./ImageGradientMagnitude
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.