MedicalDemo3
vtk-examples/Cxx/Medical/MedicalDemo3
Description¶
Composite image of three planes and translucent skin
Usage
MedicalDemo3 FullHead.mhd
Note
The skin color was selected from Table 7 in Improvement of Haar Feature Based Face Detection in OpenCV Incorporating Human Skin Color Characteristic
Note
This original source code for this example is here.
Info
See Figure 12-4 in Chapter 12 the VTK Textbook.
Info
The example uses src/Testing/Data/FullHead.mhd
which references src/Testing/Data/FullHead.raw.gz
.
Question
If you have a question about this example, please use the VTK Discourse Forum
Code¶
MedicalDemo3.cxx
// Derived from VTK/Examples/Cxx/Medical3.cxx
// This example reads a volume dataset, extracts two isosurfaces that
// represent the skin and bone, creates three orthogonal planes
// (sagittal, axial, coronal), and displays them.
//
#include <vtkActor.h>
#include <vtkCamera.h>
#include <vtkImageActor.h>
#include <vtkImageMapToColors.h>
#include <vtkImageMapper3D.h>
#include <vtkLookupTable.h>
#include <vtkMetaImageReader.h>
#include <vtkNamedColors.h>
#include <vtkNew.h>
#include <vtkOutlineFilter.h>
#include <vtkPolyDataMapper.h>
#include <vtkProperty.h>
#include <vtkRenderWindow.h>
#include <vtkRenderWindowInteractor.h>
#include <vtkRenderer.h>
#include <vtkStripper.h>
#include <vtkVersion.h>
// vtkFlyingEdges3D was introduced in VTK >= 8.2
#if VTK_MAJOR_VERSION >= 9 || (VTK_MAJOR_VERSION >= 8 && VTK_MINOR_VERSION >= 2)
#define USE_FLYING_EDGES
#else
#undef USE_FLYING_EDGES
#endif
#ifdef USE_FLYING_EDGES
#include <vtkFlyingEdges3D.h>
#else
#include <vtkMarchingCubes.h>
#endif
#include <array>
int main(int argc, char* argv[])
{
if (argc < 2)
{
cout << "Usage: " << argv[0] << " file.mhd e.g. FullHead.mhd" << endl;
return EXIT_FAILURE;
}
vtkNew<vtkNamedColors> colors;
std::array<unsigned char, 4> skinColor{{240, 184, 160, 255}};
colors->SetColor("SkinColor", skinColor.data());
std::array<unsigned char, 4> bkg{{51, 77, 102, 255}};
colors->SetColor("BkgColor", bkg.data());
// Create the renderer, the render window, and the interactor. The
// renderer draws into the render window, the interactor enables
// mouse- and keyboard-based interaction with the data within the
// render window.
//
vtkNew<vtkRenderer> aRenderer;
vtkNew<vtkRenderWindow> renWin;
renWin->AddRenderer(aRenderer);
renWin->SetWindowName("MedicalDemo3");
vtkNew<vtkRenderWindowInteractor> iren;
iren->SetRenderWindow(renWin);
// Set a background color for the renderer and set the size of the
// render window (expressed in pixels).
aRenderer->SetBackground(colors->GetColor3d("BkgColor").GetData());
renWin->SetSize(640, 480);
// The following reader is used to read a series of 2D slices (images)
// that compose the volume. The slice dimensions are set, and the
// pixel spacing. The data Endianness must also be specified. The
// reader uses the FilePrefix in combination with the slice number to
// construct filenames using the format FilePrefix.%d. (In this case
// the FilePrefix is the root name of the file: quarter.)
vtkNew<vtkMetaImageReader> reader;
reader->SetFileName(argv[1]);
reader->Update();
// An isosurface, or contour value of 500 is known to correspond to
// the skin of the patient.
// The triangle stripper is used to create triangle
// strips from the isosurface; these render much faster on may
// systems.
#ifdef USE_FLYING_EDGES
vtkNew<vtkFlyingEdges3D> skinExtractor;
#else
vtkNew<vtkMarchingCubes> skinExtractor;
#endif
skinExtractor->SetInputConnection(reader->GetOutputPort());
skinExtractor->SetValue(0, 500);
skinExtractor->Update();
vtkNew<vtkStripper> skinStripper;
skinStripper->SetInputConnection(skinExtractor->GetOutputPort());
skinStripper->Update();
vtkNew<vtkPolyDataMapper> skinMapper;
skinMapper->SetInputConnection(skinStripper->GetOutputPort());
skinMapper->ScalarVisibilityOff();
vtkNew<vtkActor> skin;
skin->SetMapper(skinMapper);
skin->GetProperty()->SetDiffuseColor(
colors->GetColor3d("SkinColor").GetData());
skin->GetProperty()->SetSpecular(0.3);
skin->GetProperty()->SetSpecularPower(20);
// An isosurface, or contour value of 1150 is known to correspond to
// the bone of the patient.
// The triangle stripper is used to create triangle
// strips from the isosurface; these render much faster on may
// systems.
#ifdef USE_FLYING_EDGES
vtkNew<vtkFlyingEdges3D> boneExtractor;
#else
vtkNew<vtkMarchingCubes> boneExtractor;
#endif
boneExtractor->SetInputConnection(reader->GetOutputPort());
boneExtractor->SetValue(0, 1150);
vtkNew<vtkStripper> boneStripper;
boneStripper->SetInputConnection(boneExtractor->GetOutputPort());
vtkNew<vtkPolyDataMapper> boneMapper;
boneMapper->SetInputConnection(boneStripper->GetOutputPort());
boneMapper->ScalarVisibilityOff();
vtkNew<vtkActor> bone;
bone->SetMapper(boneMapper);
bone->GetProperty()->SetDiffuseColor(colors->GetColor3d("Ivory").GetData());
// An outline provides context around the data.
//
vtkNew<vtkOutlineFilter> outlineData;
outlineData->SetInputConnection(reader->GetOutputPort());
outlineData->Update();
vtkNew<vtkPolyDataMapper> mapOutline;
mapOutline->SetInputConnection(outlineData->GetOutputPort());
vtkNew<vtkActor> outline;
outline->SetMapper(mapOutline);
outline->GetProperty()->SetColor(colors->GetColor3d("Black").GetData());
// Now we are creating three orthogonal planes passing through the
// volume. Each plane uses a different texture map and therefore has
// different coloration.
// Start by creating a black/white lookup table.
vtkNew<vtkLookupTable> bwLut;
bwLut->SetTableRange(0, 2000);
bwLut->SetSaturationRange(0, 0);
bwLut->SetHueRange(0, 0);
bwLut->SetValueRange(0, 1);
bwLut->Build(); // effective built
// Now create a lookup table that consists of the full hue circle
// (from HSV).
vtkNew<vtkLookupTable> hueLut;
hueLut->SetTableRange(0, 2000);
hueLut->SetHueRange(0, 1);
hueLut->SetSaturationRange(1, 1);
hueLut->SetValueRange(1, 1);
hueLut->Build(); // effective built
// Finally, create a lookup table with a single hue but having a range
// in the saturation of the hue.
vtkNew<vtkLookupTable> satLut;
satLut->SetTableRange(0, 2000);
satLut->SetHueRange(0.6, 0.6);
satLut->SetSaturationRange(0, 1);
satLut->SetValueRange(1, 1);
satLut->Build(); // effective built
// Create the first of the three planes. The filter vtkImageMapToColors
// maps the data through the corresponding lookup table created above. The
// vtkImageActor is a type of vtkProp and conveniently displays an image on
// a single quadrilateral plane. It does this using texture mapping and as
// a result is quite fast. (Note: the input image has to be unsigned char
// values, which the vtkImageMapToColors produces.) Note also that by
// specifying the DisplayExtent, the pipeline requests data of this extent
// and the vtkImageMapToColors only processes a slice of data.
vtkNew<vtkImageMapToColors> sagittalColors;
sagittalColors->SetInputConnection(reader->GetOutputPort());
sagittalColors->SetLookupTable(bwLut);
sagittalColors->Update();
vtkNew<vtkImageActor> sagittal;
sagittal->GetMapper()->SetInputConnection(sagittalColors->GetOutputPort());
sagittal->SetDisplayExtent(128, 128, 0, 255, 0, 92);
sagittal->ForceOpaqueOn();
// Create the second (axial) plane of the three planes. We use the
// same approach as before except that the extent differs.
vtkNew<vtkImageMapToColors> axialColors;
axialColors->SetInputConnection(reader->GetOutputPort());
axialColors->SetLookupTable(hueLut);
axialColors->Update();
vtkNew<vtkImageActor> axial;
axial->GetMapper()->SetInputConnection(axialColors->GetOutputPort());
axial->SetDisplayExtent(0, 255, 0, 255, 46, 46);
axial->ForceOpaqueOn();
// Create the third (coronal) plane of the three planes. We use
// the same approach as before except that the extent differs.
vtkNew<vtkImageMapToColors> coronalColors;
coronalColors->SetInputConnection(reader->GetOutputPort());
coronalColors->SetLookupTable(satLut);
coronalColors->Update();
vtkNew<vtkImageActor> coronal;
coronal->GetMapper()->SetInputConnection(coronalColors->GetOutputPort());
coronal->SetDisplayExtent(0, 255, 128, 128, 0, 92);
coronal->ForceOpaqueOn();
// It is convenient to create an initial view of the data. The
// FocalPoint and Position form a vector direction. Later on
// (ResetCamera() method) this vector is used to position the camera
// to look at the data in this direction.
vtkNew<vtkCamera> aCamera;
aCamera->SetViewUp(0, 0, -1);
aCamera->SetPosition(0, -1, 0);
aCamera->SetFocalPoint(0, 0, 0);
aCamera->ComputeViewPlaneNormal();
aCamera->Azimuth(30.0);
aCamera->Elevation(30.0);
// Actors are added to the renderer.
aRenderer->AddActor(outline);
aRenderer->AddActor(sagittal);
aRenderer->AddActor(axial);
aRenderer->AddActor(coronal);
aRenderer->AddActor(skin);
aRenderer->AddActor(bone);
// Turn off bone for this example.
bone->VisibilityOff();
// Set skin to semi-transparent.
skin->GetProperty()->SetOpacity(0.5);
// An initial camera view is created. The Dolly() method moves
// the camera towards the FocalPoint, thereby enlarging the image.
aRenderer->SetActiveCamera(aCamera);
// Calling Render() directly on a vtkRenderer is strictly forbidden.
// Only calling Render() on the vtkRenderWindow is a valid call.
renWin->Render();
aRenderer->ResetCamera();
aCamera->Dolly(1.5);
// Note that when camera movement occurs (as it does in the Dolly()
// method), the clipping planes often need adjusting. Clipping planes
// consist of two planes: near and far along the view direction. The
// near plane clips out objects in front of the plane; the far plane
// clips out objects behind the plane. This way only what is drawn
// between the planes is actually rendered.
aRenderer->ResetCameraClippingRange();
// interact with data
iren->Initialize();
iren->Start();
return EXIT_SUCCESS;
}
CMakeLists.txt¶
cmake_minimum_required(VERSION 3.12 FATAL_ERROR)
project(MedicalDemo3)
find_package(VTK COMPONENTS
)
if (NOT VTK_FOUND)
message(FATAL_ERROR "MedicalDemo3: 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(MedicalDemo3 MACOSX_BUNDLE MedicalDemo3.cxx )
target_link_libraries(MedicalDemo3 PRIVATE ${VTK_LIBRARIES}
)
# vtk_module_autoinit is needed
vtk_module_autoinit(
TARGETS MedicalDemo3
MODULES ${VTK_LIBRARIES}
)
Download and Build MedicalDemo3¶
Click here to download MedicalDemo3 and its CMakeLists.txt file. Once the tarball MedicalDemo3.tar has been downloaded and extracted,
cd MedicalDemo3/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:
./MedicalDemo3
WINDOWS USERS
Be sure to add the VTK bin directory to your path. This will resolve the VTK dll's at run time.