Skip to content

ReadSLC

vtk-examples/Cxx/IO/ReadSLC

Description

In this example you will familiarize yourself with the stages required to read a .slc file and create a visualization pipeline in VTK. Following is the three step procedure:

  1. Read the data from .slc file using vtkSLCReader

  2. Implement Marching cubes Algorithm using vtkContourFilter

  3. Create Visualization pipeline to visualize data using an actor, mapper and rendering window

Cite

This example was provided by Bharatesh Chakravarthi from Virtual Environment Lab, Chung-Ang University, Seoul, South Korea

Other languages

See (Python), (Java)

Question

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

Code

ReadSLC.cxx

#include <vtkActor.h>
#include <vtkCamera.h>
#include <vtkContourFilter.h>
#include <vtkExtractVOI.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 <vtkSLCReader.h>

// Author: Bharatesh Chakravarthi
// Affiliation: Virtual Environment Lab, Chung-Ang University, Seoul, South
// Korea

int main(int argc, char* argv[])
{
  if (argc < 2)
  {
    // Pass the filename (<filename>.slc) as parameter to read .slc file
    std::cout << "Required parameters: Filename(.slc) e.g vw_knee.slc"
              << std::endl;
    return EXIT_FAILURE;
  }

  double isoValue = 72.0;
  if (argc < 3)
  {
    isoValue = 72.0;
  }
  else
  {
    isoValue = std::atof(argv[2]);
  }
  std::string inputFilename = argv[1];

  // Using vtkSLCReader to read Volumetric file format(<filename.slc>)
  vtkNew<vtkSLCReader> reader;
  reader->SetFileName(inputFilename.c_str());
  reader->Update();

  // Implementing Marching Cubes Algorithm to create the surface using
  // vtkContourFilter object
  vtkNew<vtkContourFilter> cFilter;
  cFilter->SetInputConnection(reader->GetOutputPort());

  // Change the range(2nd and 3rd Paramater) based on your
  // requirement. recomended value for 1st parameter is above 1
  // cFilter->GenerateValues(5, 80.0, 100.0);
  cFilter->SetValue(0, isoValue);
  cFilter->Update();

  // Adding the outliner using vtkOutlineFilter object
  vtkNew<vtkOutlineFilter> outliner;
  outliner->SetInputConnection(reader->GetOutputPort());
  outliner->Update();

  // Visualize
  vtkNew<vtkPolyDataMapper> mapper;
  mapper->SetInputConnection(cFilter->GetOutputPort());
  mapper->SetScalarVisibility(0);

  vtkNew<vtkNamedColors> colors;

  vtkNew<vtkActor> actor;
  actor->SetMapper(mapper);
  actor->GetProperty()->SetDiffuse(0.8);
  actor->GetProperty()->SetDiffuseColor(colors->GetColor3d("Ivory").GetData());
  actor->GetProperty()->SetSpecular(0.8);
  actor->GetProperty()->SetSpecularPower(120.0);

  // extractVOI is used to fix the problem of subsampling of data and reduce
  // slow interaction and increase loading speed
  vtkNew<vtkExtractVOI> extractVOI;
  extractVOI->SetInputConnection(reader->GetOutputPort());
  extractVOI->SetSampleRate(2, 2, 2);
  extractVOI->Update();

  vtkNew<vtkRenderer> renderer;
  vtkNew<vtkRenderWindow> renderWindow;
  renderWindow->AddRenderer(renderer);
  renderWindow->SetSize(640, 512);

  vtkNew<vtkRenderWindowInteractor> renderWindowInteractor;
  renderWindowInteractor->SetRenderWindow(renderWindow);

  renderer->AddActor(actor);
  renderer->SetBackground(colors->GetColor3d("SlateGray").GetData());
  renderWindow->Render();

  // Pick a good view
  vtkCamera* cam1 = renderer->GetActiveCamera();
  cam1->SetFocalPoint(0.0, 0.0, 0.0);
  cam1->SetPosition(0.0, -1.0, 0.0);
  cam1->SetViewUp(0.0, 0.0, -1.0);
  cam1->Azimuth(-90.0);
  renderer->ResetCamera();
  renderer->ResetCameraClippingRange();

  renderWindow->SetWindowName("ReadSLC");
  renderWindow->Render();
  renderWindowInteractor->Start();

  return EXIT_SUCCESS;
}

CMakeLists.txt

cmake_minimum_required(VERSION 3.12 FATAL_ERROR)

project(ReadSLC)

find_package(VTK COMPONENTS 
)

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

Download and Build ReadSLC

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

cd ReadSLC/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:

./ReadSLC

WINDOWS USERS

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