ImageShiftScale
vtk-examples/Cxx/Images/ImageShiftScale
Question
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Code¶
ImageShiftScale.cxx
#include <vtkImageData.h>
#include <vtkImageProperty.h>
#include <vtkImageShiftScale.h>
#include <vtkImageSlice.h>
#include <vtkImageSliceMapper.h>
#include <vtkInteractorStyleImage.h>
#include <vtkNamedColors.h>
#include <vtkNew.h>
#include <vtkRenderWindow.h>
#include <vtkRenderWindowInteractor.h>
#include <vtkRenderer.h>
namespace {
void CreateImage(vtkImageData*);
}
int main(int, char*[])
{
vtkNew<vtkNamedColors> colors;
// Create an image.
vtkNew<vtkImageData> image;
CreateImage(image);
vtkNew<vtkImageShiftScale> shiftScaleFilter;
shiftScaleFilter->SetOutputScalarTypeToUnsignedChar();
shiftScaleFilter->SetInputData(image);
shiftScaleFilter->SetShift(100);
shiftScaleFilter->SetScale(1);
shiftScaleFilter->Update();
// Create actors.
vtkNew<vtkImageSliceMapper> originalSliceMapper;
originalSliceMapper->SetInputData(image);
vtkNew<vtkImageSlice> originalSlice;
originalSlice->SetMapper(originalSliceMapper);
originalSlice->GetProperty()->SetInterpolationTypeToNearest();
vtkNew<vtkImageSliceMapper> shiftScaleMapper;
shiftScaleMapper->SetInputConnection(shiftScaleFilter->GetOutputPort());
vtkNew<vtkImageSlice> shiftScaleSlice;
shiftScaleSlice->SetMapper(shiftScaleMapper);
shiftScaleSlice->GetProperty()->SetInterpolationTypeToNearest();
// Define viewport ranges.
// (xmin, ymin, xmax, ymax)
double originalViewport[4] = {0.0, 0.0, 0.5, 1.0};
double shiftScaleViewport[4] = {0.5, 0.0, 1.0, 1.0};
// Setup renderers
vtkNew<vtkRenderer> originalRenderer;
originalRenderer->SetViewport(originalViewport);
originalRenderer->AddViewProp(originalSlice);
originalRenderer->ResetCamera();
originalRenderer->SetBackground(
colors->GetColor3d("CornflowerBlue").GetData());
vtkNew<vtkRenderer> shiftScaleRenderer;
shiftScaleRenderer->SetViewport(shiftScaleViewport);
shiftScaleRenderer->AddViewProp(shiftScaleSlice);
shiftScaleRenderer->ResetCamera();
shiftScaleRenderer->SetBackground(colors->GetColor3d("SteelBlue").GetData());
vtkNew<vtkRenderWindow> renderWindow;
renderWindow->SetSize(600, 300);
renderWindow->AddRenderer(originalRenderer);
renderWindow->AddRenderer(shiftScaleRenderer);
renderWindow->SetWindowName("ImageShiftScale");
vtkNew<vtkRenderWindowInteractor> renderWindowInteractor;
vtkNew<vtkInteractorStyleImage> style;
renderWindowInteractor->SetInteractorStyle(style);
renderWindowInteractor->SetRenderWindow(renderWindow);
renderWindow->Render();
renderWindowInteractor->Initialize();
renderWindowInteractor->Start();
return EXIT_SUCCESS;
}
namespace {
void CreateImage(vtkImageData* image)
{
unsigned int dim = 20;
image->SetDimensions(dim, dim, 1);
image->AllocateScalars(VTK_UNSIGNED_CHAR, 1);
for (unsigned int x = 0; x < dim; x++)
{
for (unsigned int y = 0; y < dim; y++)
{
unsigned char* pixel =
static_cast<unsigned char*>(image->GetScalarPointer(x, y, 0));
if (x < dim / 2)
{
pixel[0] = 50;
}
else
{
pixel[0] = 150;
}
}
}
image->Modified();
}
} // namespace
CMakeLists.txt¶
cmake_minimum_required(VERSION 3.12 FATAL_ERROR)
project(ImageShiftScale)
find_package(VTK COMPONENTS
)
if (NOT VTK_FOUND)
message(FATAL_ERROR "ImageShiftScale: 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(ImageShiftScale MACOSX_BUNDLE ImageShiftScale.cxx )
target_link_libraries(ImageShiftScale PRIVATE ${VTK_LIBRARIES}
)
# vtk_module_autoinit is needed
vtk_module_autoinit(
TARGETS ImageShiftScale
MODULES ${VTK_LIBRARIES}
)
Download and Build ImageShiftScale¶
Click here to download ImageShiftScale and its CMakeLists.txt file. Once the tarball ImageShiftScale.tar has been downloaded and extracted,
cd ImageShiftScale/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:
./ImageShiftScale
WINDOWS USERS
Be sure to add the VTK bin directory to your path. This will resolve the VTK dll's at run time.