MedicalDemo3
Repository source: 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
The 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.
Other languages
See (Python), (PythonicAPI), (Java)
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 <vtkCameraOrientationRepresentation.h>
#include <vtkCameraOrientationWidget.h>
#include <vtkFlyingEdges3D.h>
#include <vtkImageActor.h>
#include <vtkImageMapToColors.h>
#include <vtkImageMapper3D.h>
#include <vtkImageResliceMapper.h>
#include <vtkInteractorStyleSwitch.h>
#include <vtkLookupTable.h>
#include <vtkMetaImageReader.h>
#include <vtkNamedColors.h>
#include <vtkNew.h>
#include <vtkOutlineFilter.h>
#include <vtkPlane.h>
#include <vtkPolyDataMapper.h>
#include <vtkProperty.h>
#include <vtkRenderWindow.h>
#include <vtkRenderWindowInteractor.h>
#include <vtkRenderer.h>
#include <vtkStripper.h>
#include <vtkVersion.h>
#include <vtk_cli11.h>
#include <vtk_fmt.h>
// clang-format off
#include VTK_FMT(fmt/format.h)
// clang-format on
#include <array>
#include <filesystem>
namespace {
typedef std::map<std::string, std::string> TAxisParams;
typedef std::map<std::string, TAxisParams> TAxesParams;
/**
* @brief Define the axes labels.
*
* @return The axes labels.
*/
TAxesParams DefineAxesLabels();
/**
* @brief Define the axes colors.
*
* @return The axes colors.
*/
TAxesParams DefineAxesColors();
/**
* @brief Gather the defined axes labels and colors into a map.
*
* @return The map of axes labels and colors.
*/
std::map<std::string, std::pair<TAxisParams, TAxisParams>> GetAxesParams();
/**
* @brief Make a camera orientation widget for a given renderer.
*
* position has these values 0: LowerLeft, 1: UpperLeft, 2: LowerRight, 3:
* UpperRight
*
* @param ren The renderer.
* @param alc The key specifying the desired labels and colors for the axes.
* @param colors A reference to the vtkNamedColors object.
* @param reposition Move the camera orientation widget to upper left.
*
* @return The camera orientation widget.
*/
vtkSmartPointer<vtkCameraOrientationWidget>
MakeCameraOrientationWidget(vtkRenderer* ren, std::string alcKey = "xyz",
int const& position = 3);
} // namespace
namespace fs = std::filesystem;
int main(int argc, char* argv[])
{
CLI::App app{"A Composite image of three planes and translucent skin "
"extracted from a CT dataset of the head."};
// Define options
std::string fileName;
app.add_option("fileName", fileName,
"The path to the data file e.g. FullHead.mhd.")
->required()
->check(CLI::ExistingFile);
bool flyingEdges = true;
app.add_flag("-m{false},!-n", flyingEdges,
"Use flying edges by default, marching cubes if set.");
CLI11_PARSE(app, argc, argv);
if (flyingEdges)
{
#define USE_FLYING_EDGES
}
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> ren;
vtkNew<vtkRenderWindow> renWin;
// Set a background color for the renderer and set the size of the
// render window (expressed in pixels).
ren->SetBackground(colors->GetColor3d("BkgColor").GetData());
renWin->SetSize(640, 480);
auto appFn = fs::path((app.get_name())).stem().string();
renWin->SetWindowName(appFn.c_str());
renWin->AddRenderer(ren);
vtkNew<vtkRenderWindowInteractor> iren;
iren->SetRenderWindow(renWin);
auto is = vtkInteractorStyleSwitch::SafeDownCast(iren->GetInteractorStyle());
if (is)
{
is->SetCurrentStyleToTrackballCamera();
}
// 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();
auto bounds = skinMapper->GetBounds();
std::array<double, 3> centroid{0.0, 0.0, 0.0};
for (auto i = 0; i < 6; i += 2)
{
auto x = bounds[i];
auto y = bounds[i + 1];
centroid[(i + 1) / 2] = x + (y - x) / 2.0;
}
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> outlineMapper;
outlineMapper->SetInputConnection(outlineData->GetOutputPort());
vtkNew<vtkActor> outline;
outline->SetMapper(outlineMapper);
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
// Use vtkImageMapToColors to map the scalar components of an input image
// through a lookup table to produce an RGBA or RGB output imag
// Then create a slice planes through a 3D image volume using
// vtkImageSlice, combining it with a vtkImageResliceMapper and a vtkPlane.
// Create the first (saggital) plane of the three planes.
vtkNew<vtkImageMapToColors> sagittalColors;
sagittalColors->SetInputConnection(reader->GetOutputPort());
sagittalColors->SetLookupTable(bwLut);
sagittalColors->Update();
vtkNew<vtkPlane> sp;
sp->SetOrigin(centroid.data());
sp->SetNormal(1, 0, 0);
vtkNew<vtkImageResliceMapper> sagittalMapper;
sagittalMapper->SetInputConnection(sagittalColors->GetOutputPort());
sagittalMapper->SetSlicePlane(sp); // Apply the custom slice plane
vtkNew<vtkImageSlice> sagittalSlice;
sagittalSlice->SetMapper(sagittalMapper);
// 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<vtkPlane> ap;
ap->SetOrigin(centroid.data());
ap->SetNormal(0, 0, 1);
vtkNew<vtkImageResliceMapper> axialMapper;
axialMapper->SetInputConnection(axialColors->GetOutputPort());
axialMapper->SetSlicePlane(ap); // Apply the custom slice plane
vtkNew<vtkImageSlice> axialSlice;
axialSlice->SetMapper(axialMapper);
// 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<vtkPlane> cp;
cp->SetOrigin(centroid.data());
cp->SetNormal(0, 1, 0);
vtkNew<vtkImageResliceMapper> coronalMapper;
coronalMapper->SetInputConnection(coronalColors->GetOutputPort());
coronalMapper->SetSlicePlane(cp); // Apply the custom slice plane
vtkNew<vtkImageSlice> coronalSlice;
coronalSlice->SetMapper(coronalMapper);
// Turn off bone for this example.
bone->VisibilityOff();
// Set skin to semi-transparent.
skin->GetProperty()->SetOpacity(0.5);
// 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> camera;
camera->SetViewUp(0, 0, 1);
camera->SetPosition(0, -1, 0);
camera->SetFocalPoint(0, 0, 0);
camera->ComputeViewPlaneNormal();
camera->Azimuth(30.0);
camera->Elevation(30.0);
// Actors are added to the renderer.
ren->AddActor(outline);
ren->AddActor(sagittalSlice);
ren->AddActor(axialSlice);
ren->AddActor(coronalSlice);
ren->AddActor(skin);
ren->AddActor(bone);
// An initial camera view is created. The Dolly() method moves
// the camera towards the FocalPoint, thereby enlarging the image.
ren->SetActiveCamera(camera);
ren->ResetCamera();
camera->Dolly(1.5);
// Calling Render() directly on a vtkRenderer is strictly forbidden.
// Only calling Render() on the vtkRenderWindow is a valid call.
// renWin->Render();
// 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.
ren->ResetCameraClippingRange();
// Important: The interactor must be set prior to enabling the widget.
auto cow = MakeCameraOrientationWidget(ren);
cow->On();
auto category = "lrpasi";
auto cow1 = MakeCameraOrientationWidget(ren, category, 1);
cow1->On();
// Interact with the data.
iren->Initialize();
iren->Start();
return EXIT_SUCCESS;
}
namespace {
TAxesParams DefineAxesLabels()
{
// clang-format off
return {
// Labels are: Anterior, Posterior, Dorsal, Ventral, Left, Right
{"apdvlr", {{"+X", "A"},{"-X", "P"},{"+Y", "D"},{"-Y", "V"},{"+Z", "L"},{"-Z", "R"}}},
{"apdvrl",{{"+X", "A"},{"-X", "P"},{"+Y", "D"},{"-Y", "V"},{"+Z", "R"},{"-Z", "L"}}},
{"padvlr", {{"+X", "P"},{"-X", "A"},{"+Y", "D"},{"-Y", "V"},{"+Z", "L"},{"-Z", "R"}}},
// Labels are: Left, Right, Superior, Inferior, Anterior, Posterior
{"lrsiap",{{"+X", "L"},{"-X", "R"},{"+Y", "S"},{"-Y", "I"},{"+Z", "A"},{"-Z", "P"}}},
{"lrpasi",{{"+X", "L"},{"-X", "R"},{"+Y", "P"},{"-Y", "A"},{"+Z", "S"},{"-Z", "I"}}},
{"rlpais",{{"+X", "R"},{"-X", "L"},{"+Y", "P"},{"-Y", "A"},{"+Z", "I"},{"-Z", "S"}}},
{"lrpasi", {}},
{"rlpais", {}},
// Default labels.
{"xyz", {}},
};
// clang-format on
}
TAxesParams DefineAxesColors()
{
// clang-format off
TAxisParams color1{{"+X", "IndianRed"},{"-X", "FireBrick"},
{"+Y", "LimeGreen"},{"-Y", "DarkGreen"},
{"+Z", "Blue"}, {"-Z", "SteelBlue"}};
return {
{"apdvlr",color1},
{"apdvrl",color1},
{"padvlr",color1},
{"lrsiap",color1},
// Default colors.
{"xyz", {}},
};
// clang-format on
}
std::map<std::string, std::pair<TAxisParams, TAxisParams>> GetAxesParams()
{
vtkNew<vtkNamedColors> colors;
// The keys must be the same.
auto axesLabels = DefineAxesLabels();
auto axesColors = DefineAxesColors();
// Get the keys.
std::set<std::string> labelKeys;
for (auto&& label : axesLabels)
{
labelKeys.insert(label.first);
}
std::set<std::string> colorKeys;
for (auto&& label : axesLabels)
{
colorKeys.insert(label.first);
}
std::vector<std::string> commonKeys;
std::set_intersection(labelKeys.begin(), labelKeys.end(), colorKeys.begin(),
colorKeys.end(), std::back_inserter(commonKeys));
std::map<std::string, std::pair<TAxisParams, TAxisParams>> alc;
for (auto&& k : commonKeys)
{
alc[k] = std::pair<TAxisParams, TAxisParams>{axesLabels[k], axesColors[k]};
}
return alc;
};
vtkSmartPointer<vtkCameraOrientationWidget>
MakeCameraOrientationWidget(vtkRenderer* ren, std::string alcKey,
int const& reposition)
{
vtkNew<vtkCameraOrientationWidget> cow;
cow->SetParentRenderer(ren);
cow->EnabledOn();
auto axesParameters = GetAxesParams();
std::set<std::string> keys;
for (auto&& label : axesParameters)
{
keys.insert(label.first);
}
auto it = keys.find(alcKey);
if (it == keys.end())
{
std::string res =
"Invalid key for axes labels and colors.\nValid keys are: ";
for (const auto& [key, value] : axesParameters)
{
res += fmt::format("{:s}, ", key);
}
if (res.length() >= 2)
{
auto pos = res.length() - 2;
res.replace(pos, 2, "");
}
res += "\nUsing the key: xyz";
std::cout << res << std::endl;
alcKey = "xyz";
}
auto alc = axesParameters[alcKey];
vtkNew<vtkCameraOrientationRepresentation> rep;
switch (reposition)
{
case 0:
rep->AnchorToLowerLeft();
break;
case 1:
rep->AnchorToUpperLeft();
break;
case 2:
rep->AnchorToLowerRight();
break;
default:
rep->AnchorToUpperRight();
}
if (!alc.first.empty())
{
rep->SetXPlusLabelText(alc.first["+X"]);
rep->SetXMinusLabelText(alc.first["-X"]);
rep->SetYPlusLabelText(alc.first["+Y"]);
rep->SetYMinusLabelText(alc.first["-Y"]);
rep->SetZPlusLabelText(alc.first["+Z"]);
rep->SetZMinusLabelText(alc.first["-Z"]);
}
if (!alc.second.empty())
{
vtkNew<vtkNamedColors> colors;
rep->SetXAxisColor(colors->GetColor3d(alc.second["+X"]).GetData());
rep->SetYAxisColor(colors->GetColor3d(alc.second["+Y"]).GetData());
rep->SetZAxisColor(colors->GetColor3d(alc.second["+Z"]).GetData());
}
cow->SetRepresentation(rep);
cow->Off();
return cow;
}
} // namespace
CMakeLists.txt¶
cmake_minimum_required(VERSION 3.12 FATAL_ERROR)
project(MedicalDemo3)
find_package(VTK COMPONENTS
CommonColor
CommonCore
FiltersCore
FiltersModeling
IOImage
ImagingCore
InteractionStyle
RenderingContextOpenGL2
RenderingCore
RenderingFreeType
RenderingGL2PSOpenGL2
RenderingOpenGL2
)
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.
