Exemplo n.º 1
0
void Horus::getPCA(const vector<cv::Point> &contour, float &center, float &angle)
{
    //Construct a buffer used by the pca analysis
    int sz = static_cast<int>(contour.size());
    Mat data_pts = Mat(sz, 2, CV_32FC1);
    for (int i = 0; i < data_pts.rows; ++i) {
        data_pts.at<float>(i, 0) = contour[i].x;
        data_pts.at<float>(i, 1) = contour[i].y;
    }

    //Perform PCA analysis
    PCA pca_analysis(data_pts, Mat(), CV_PCA_DATA_AS_ROW);

    //Store the center of the object
    cv::Point cntr = cv::Point(static_cast<int>(pca_analysis.mean.at<float>(0, 0)),
                               static_cast<int>(pca_analysis.mean.at<float>(0, 1)));

    //Store the eigenvalues and eigenvectors
    vector<cv::Point2d> eigen_vecs(2);
    vector<float> eigen_val(2);
    for (int i = 0; i < 2; ++i) {
        eigen_vecs[i] = Point2d(pca_analysis.eigenvectors.at<float>(i, 0), 
                                pca_analysis.eigenvectors.at<float>(i, 1));
        eigen_val[i] = pca_analysis.eigenvalues.at<float>(0, i);
    }

    angle = atan2(eigen_vecs[0].y, eigen_vecs[0].x); // orientation in radians
}
double HandDetector::GetOrientation(const vector<Point> &pts, Mat &img)
{
    if (pts.size() == 0) return false;

    //Construct a buffer used by the pca analysis
    Mat data_pts = Mat(pts.size(), 2, CV_64FC1);
    for (int i = 0; i < data_pts.rows; ++i)
    {
        data_pts.at<double>(i, 0) = pts[i].x;
        data_pts.at<double>(i, 1) = pts[i].y;
    }


    //Perform PCA analysis
    PCA pca_analysis(data_pts, Mat(), CV_PCA_DATA_AS_ROW);

    //Store the position of the object
    Point pos = Point(pca_analysis.mean.at<double>(0, 0),
                      pca_analysis.mean.at<double>(0, 1));

    //Store the eigenvalues and eigenvectors
    vector<Point2d> eigen_vecs(2);
    vector<double> eigen_val(2);
    for (int i = 0; i < 2; ++i)
    {
        eigen_vecs[i] = Point2d(pca_analysis.eigenvectors.at<double>(i, 0),
                                pca_analysis.eigenvectors.at<double>(i, 1));

        eigen_val[i] = pca_analysis.eigenvalues.at<double>(i);
    }

    // Draw the principal components
    circle(img, pos, 3, CV_RGB(255, 0, 255), 2);
    //line(img, pos, pos + 0.02 * Point(eigen_vecs[0].x * eigen_val[0], eigen_vecs[0].y * eigen_val[0]) , CV_RGB(255, 255, 0));
    //line(img, pos, pos + 0.02 * Point(eigen_vecs[1].x * eigen_val[1], eigen_vecs[1].y * eigen_val[1]) , CV_RGB(0, 255, 255));

	Point p1 = pos + 0.02 * Point(eigen_vecs[0].x * eigen_val[0], eigen_vecs[0].y * eigen_val[0]);
    Point p2 = pos + 0.02 * Point(eigen_vecs[1].x * eigen_val[1], eigen_vecs[1].y * eigen_val[1]);
    

	DrawAxis(img, pos, p1, Scalar(0, 255, 0), 1);
    DrawAxis(img, pos, p2, Scalar(255, 255, 0), 5);


    return atan2(eigen_vecs[0].y, eigen_vecs[0].x)*(180/CV_PI);

}
Exemplo n.º 3
0
// Calculate the angle in degrees of a certain line.
double NaoVision::getAngleDegrees(const vector<Point> &pts, Mat &img) {
    // Construct a buffer used by the pca analysis.
    int sz = static_cast<int>(pts.size());
    Mat data_pts = Mat(sz, 2, CV_64FC1);

    for(int i = 0; i < data_pts.rows; ++i) {
        data_pts.at<double>(i, 0) = pts[i].x;
        data_pts.at<double>(i, 1) = pts[i].y;
    }

    // Perform PCA analysis.
    PCA pca_analysis(data_pts, Mat(), CV_PCA_DATA_AS_ROW);

    // Store the center of the object.
    Point cntr = Point(static_cast<int>(pca_analysis.mean.at<double>(0, 0)),
                      static_cast<int>(pca_analysis.mean.at<double>(0, 1)));

    // Store the eigenvalues and eigenvectors.
    vector<Point2d> eigen_vecs(2);
    vector<double> eigen_val(2);

    for(int i = 0; i < 2; ++i) {
        eigen_vecs[i] = Point2d(pca_analysis.eigenvectors.at<double>(i, 0),
                                pca_analysis.eigenvectors.at<double>(i, 1));
        eigen_val[i] = pca_analysis.eigenvalues.at<double>(0, i);
    }

    // Draw the principal components.
    circle(img, cntr, 3, Scalar(255, 0, 255), 2);
    Point p1 = cntr + 0.02 * Point(static_cast<int>(eigen_vecs[0].x * eigen_val[0]), static_cast<int>(eigen_vecs[0].y * eigen_val[0]));
    Point p2 = cntr - 0.02 * Point(static_cast<int>(eigen_vecs[1].x * eigen_val[1]), static_cast<int>(eigen_vecs[1].y * eigen_val[1]));
    drawAxis(img, cntr, p1, Scalar(0, 255, 0), 1);
    drawAxis(img, cntr, p2, Scalar(255, 255, 0), 5);

    double angle = atan2(eigen_vecs[0].y, eigen_vecs[0].x);     // Angle in radians.
    double degrees = angle * 180 / CV_PI;                       // Convert radians to degrees (0-180 range).
    degrees = degrees < 0 ? degrees + 180 : degrees;

    return degrees;
}
double Segmentation::getOrientation(std::vector<cv::Point> &pts, cv::Mat &img)
{    
	 if (pts.size() == 0) return false;

    //Construct a buffer used by the pca analysis
    cv::Mat data_pts = cv::Mat(pts.size(), 2, CV_64FC1);
    for (int i = 0; i < data_pts.rows; ++i)
    {
        data_pts.at<double>(i, 0) = pts[i].x;
        data_pts.at<double>(i, 1) = pts[i].y;
    }


    //Perform PCA analysis
    cv::PCA pca_analysis(data_pts, cv::Mat(), CV_PCA_DATA_AS_ROW);

    //Store the position of the object
    cv::Point2i pos = cv::Point2i(static_cast<int>(pca_analysis.mean.at<double>(0, 0)),
                     static_cast<int>(pca_analysis.mean.at<double>(0, 1)));


    //Store the eigenvalues and eigenvectors
    std::vector<cv::Point2d> eigen_vecs(2);
    std::vector<double> eigen_val(2);
    for (int i = 0; i < 2; ++i)
    {
        eigen_vecs[i] = cv::Point2d(pca_analysis.eigenvectors.at<double>(i, 0),
                                pca_analysis.eigenvectors.at<double>(i, 1));

        eigen_val[i] = pca_analysis.eigenvalues.at<double>(0, i);
    }

    // Draw the principal components
    cv::circle(img, pos, 3, CV_RGB(255, 0, 255), 2);
    cv::line(img, pos, pos + 0.02 * cv::Point(static_cast<int>(eigen_vecs[0].x * eigen_val[0]),static_cast<int> (eigen_vecs[0].y * eigen_val[0])) , CV_RGB(255, 255, 0));
    cv::line(img, pos, pos + 0.02 * cv::Point(static_cast<int>(eigen_vecs[1].x * eigen_val[1]), static_cast<int>(eigen_vecs[1].y * eigen_val[1])) , CV_RGB(0, 255, 255));
	
    return atan2(eigen_vecs[0].y, eigen_vecs[0].x);
}
Exemplo n.º 5
0
void Projector::objProjectionOffline(std::string objPath, std::string objName, bool gpuView)
{
	std::cout << "Camera init: ";
	objObject obj(objPath, objName);
	obj.loadData();
	cout << "DONE\n";
	cv::namedWindow("objTest", CV_WINDOW_NORMAL);
	cv::moveWindow("objTest", 0, 0);
	indices.resize(480);
	for (int i = 0; i < 480; i++) indices[i].resize(640);

	libfreenect2::Registration* registration = new libfreenect2::Registration(_dev->getIrCameraParams(), _dev->getColorCameraParams());
	libfreenect2::Frame undistorted(512, 424, 4), registered(512, 424, 4);
	libfreenect2::FrameMap frames;
	SimpleViewer viewer;
	bool shutdown = false;
	cv::Mat board(480, 640, CV_8UC4, cv::Scalar::all(255));
	cv::Vec3f prevNormal(-1, -1, -1);
	if (!gpuView) {
		cv::namedWindow("reprojection", CV_WINDOW_NORMAL);
		cv::moveWindow("reprojection", 200, 200);
		//setWindowProperty("reprojection", CV_WND_PROP_FULLSCREEN, CV_WINDOW_FULLSCREEN);
	}
	else {
		viewer.setSize(480, 640); // TO-DO change resolution
		viewer.initialize();
		libfreenect2::Frame b(640, 480, 4);
		b.data = board.data;
		viewer.addFrame("RGB", &b);
		shutdown = shutdown || viewer.render();
	}
	while (!shutdown)
	{
		board = cv::Mat(480, 640, CV_8UC4, cv::Scalar::all(255));
		std::vector<cv::Point3f> plnSrc;
		if (!gpuView) cv::imshow("reprojection", board);
		(_listener)->waitForNewFrame(frames);
		libfreenect2::Frame *rgb = frames[libfreenect2::Frame::Color];
		libfreenect2::Frame *depth = frames[libfreenect2::Frame::Depth];
		registration->apply(rgb, depth, &undistorted, &registered, true, NULL, NULL);

		PlaneData pln = findRectangle(registration, &undistorted, &registered);

		if (pln.points.size() > 0) {
			std::vector<cv::Point2f> projected = projectPoints(pln.points);
			cv::Mat cont = cv::Mat(480, 640, CV_8UC1, cv::Scalar::all(0));

			for (int i = 0; i < projected.size(); i++)
			{
				if (480 - projected[i].x >0 && projected[i].y > 0 && 480 - projected[i].x < 475 && projected[i].y < 630) {

					cv::Mat ROI = board(cv::Rect(static_cast<int>(projected[i].y), static_cast<int>(480 - projected[i].x), 2, 2));
					ROI.setTo(cv::Scalar(250, 100, 100, 100));
					cont.at<uchar>(static_cast<int>(480 - projected[i].x), static_cast<int>(projected[i].y), 0) = 255;
					plnSrc.push_back(pln.points[i]);
				}
			}
			vector<vector<cv::Point> > contours;
			vector<cv::Vec4i> hierarchy;
			cv::GaussianBlur(cont, cont, cv::Size(7, 7), 5, 11);
			findContours(cont, contours, hierarchy, cv::RETR_CCOMP, cv::CHAIN_APPROX_NONE, cv::Point(0, 0));

			vector<vector<cv::Point> > contours_poly(contours.size());
			vector<cv::Rect> boundRect(contours.size());
			vector<cv::Point2f>center(contours.size());
			vector<float>radius(contours.size());

			for (int i = 0; i < contours.size(); i++)
			{
				cv::approxPolyDP(cv::Mat(contours[i]), contours_poly[i], 10, true);
			}

			for (int i = 0; i < contours.size(); i++)
			{
				drawContours(board, contours_poly, 0, cv::Scalar(0, 255, 0), 5);
			}


			cv::Mat data_pts = cv::Mat(300, 3, CV_64FC1);
			cv::Vec3f normal(0, 0, 0);
			int jump = plnSrc.size() / 300;
			for (int i = 0; i < 100; i++) {
				data_pts.at<double>(i, 0) = plnSrc[i*jump].x;
				data_pts.at<double>(i, 1) = plnSrc[i*jump].y;
				data_pts.at<double>(i, 2) = plnSrc[i*jump].z;
				data_pts.at<double>(i + 100, 0) = plnSrc[(i + 100)*jump].x;
				data_pts.at<double>(i + 100, 1) = plnSrc[(i + 100)*jump].y;
				data_pts.at<double>(i + 100, 2) = plnSrc[(i + 100)*jump].z;
				data_pts.at<double>(i + 200, 0) = plnSrc[(i + 200) *jump].x;
				data_pts.at<double>(i + 200, 1) = plnSrc[(i + 200)*jump].y;
				data_pts.at<double>(i + 200, 2) = plnSrc[(i + 200)*jump].z;
			}

			cv::PCA pca_analysis(data_pts, cv::Mat(), CV_PCA_DATA_AS_ROW);
			cv::Vec3f cntr = cv::Vec3f((pca_analysis.mean.at<double>(0, 0)),
				(pca_analysis.mean.at<double>(0, 1)),
				(pca_analysis.mean.at<double>(0, 2)));

			vector<cv::Point3f> eigen_vecs(2);
			vector<double> eigen_val(2);
			for (int i = 0; i < 2; ++i)
			{
				eigen_vecs[i] = cv::Point3f(pca_analysis.eigenvectors.at<double>(i, 0),
					pca_analysis.eigenvectors.at<double>(i, 1),
					pca_analysis.eigenvectors.at<double>(i, 2));
				eigen_val[i] = pca_analysis.eigenvalues.at<double>(0, i);
			}
			cv::Vec3f p1 = cv::Vec3f((eigen_vecs[0].x * eigen_val[0]), (eigen_vecs[0].y * eigen_val[0]), (eigen_vecs[0].z * eigen_val[0]));
			cv::Vec3f p2 = cv::Vec3f((eigen_vecs[1].x * eigen_val[1]), (eigen_vecs[1].y * eigen_val[1]), (eigen_vecs[1].z * eigen_val[1]));
			normal = p1.cross(p2);
			normal = cv::normalize(normal);
			//pln.center = cntr;

			pln.normal = normal;
			obj.setCamera(cv::Point3f(pln.center.x, -pln.center.y, -pln.center.z + 150),
				cv::Vec3f(pln.normal[0], pln.normal[1], pln.normal[2]));

			if (!gpuView) imshow("reprojection", board);
			else {
				libfreenect2::Frame b(640, 480, 4);
				b.data = board.data;
				viewer.addFrame("RGB", &b);
				shutdown = shutdown || viewer.render();
			}
		}
		cv::Mat im = obj.render();
		cv::imshow("objTest", im);
		//}
		(_listener)->release(frames);
		if (!gpuView) {
			int op = cv::waitKey(50);
			if (op == 100 || (char)(op) == 'd') right -= 1;
			if (op == 115 || (char)(op) == 's') up += 1;
			if (op == 97 || (char)(op) == 'a') right += 1;
			if (op == 119 || (char)(op) == 'w') up -= 1;

			if (op == 114 || (char)(op) == 'r') rotX -= 0.5;
			if (op == 102 || (char)(op) == 'f') rotX += 0.5;

			if (op == 1113997 || op == 1048586 || op == 1048608 || op == 10 || op == 32)
			{
				std::cout << "right = " << right << ";\nup = " << up << ";\nrotX = " << rotX << ";\n";
				break;
			}
		}
		else {
			//right = 0;
			//up = 0;
			//rotX = 0;
			right = viewer.offsetX;
			up = viewer.offsetY;
			rotX = viewer.rot;
		}
	}
	if (!gpuView) cv::destroyWindow("reprojection");
	else {
		viewer.stopWindow();
	}
	cv::destroyWindow("objTest");
}
Exemplo n.º 6
0
mitk::GIFVolumetricStatistics::FeatureListType mitk::GIFVolumetricStatistics::CalculateFeatures(const Image::Pointer & image, const Image::Pointer &mask)
{
  FeatureListType featureList;
  if (image->GetDimension() < 3)
  {
    return featureList;
  }


  AccessByItk_3(image, CalculateVolumeStatistic, mask, featureList, FeatureDescriptionPrefix());
  AccessByItk_3(mask, CalculateLargestDiameter, image, featureList, FeatureDescriptionPrefix());

  vtkSmartPointer<vtkImageMarchingCubes> mesher = vtkSmartPointer<vtkImageMarchingCubes>::New();
  vtkSmartPointer<vtkMassProperties> stats = vtkSmartPointer<vtkMassProperties>::New();
  mesher->SetInputData(mask->GetVtkImageData());
  mesher->SetValue(0, 0.5);
  stats->SetInputConnection(mesher->GetOutputPort());
  stats->Update();

  double pi = vnl_math::pi;

  double meshVolume = stats->GetVolume();
  double meshSurf = stats->GetSurfaceArea();
  double pixelVolume = featureList[1].second;
  double pixelSurface = featureList[3].second;

  MITK_INFO << "Surface: " << pixelSurface << " Volume: " << pixelVolume;

  double compactness1 = pixelVolume / (std::sqrt(pi) * std::pow(meshSurf, 2.0 / 3.0));
  double compactness1Pixel = pixelVolume / (std::sqrt(pi) * std::pow(pixelSurface, 2.0 / 3.0));
  //This is the definition used by Aertz. However, due to 2/3 this feature is not demensionless. Use compactness3 instead.

  double compactness2 = 36 * pi*pixelVolume*pixelVolume / meshSurf / meshSurf / meshSurf;
  double compactness2MeshMesh = 36 * pi*meshVolume*meshVolume / meshSurf / meshSurf / meshSurf;
  double compactness2Pixel = 36 * pi*pixelVolume*pixelVolume / pixelSurface / pixelSurface / pixelSurface;
  double compactness3 = pixelVolume / (std::sqrt(pi) * std::pow(meshSurf, 3.0 / 2.0));
  double compactness3MeshMesh = meshVolume / (std::sqrt(pi) * std::pow(meshSurf, 3.0 / 2.0));
  double compactness3Pixel = pixelVolume / (std::sqrt(pi) * std::pow(pixelSurface, 3.0 / 2.0));

  double sphericity = std::pow(pi, 1 / 3.0) *std::pow(6 * pixelVolume, 2.0 / 3.0) / meshSurf;
  double sphericityMesh = std::pow(pi, 1 / 3.0) *std::pow(6 * meshVolume, 2.0 / 3.0) / meshSurf;
  double sphericityPixel = std::pow(pi, 1 / 3.0) *std::pow(6 * pixelVolume, 2.0 / 3.0) / pixelSurface;
  double surfaceToVolume = meshSurf / meshVolume;
  double surfaceToVolumePixel = pixelSurface / pixelVolume;
  double sphericalDisproportion = meshSurf / 4 / pi / std::pow(3.0 / 4.0 / pi * pixelVolume, 2.0 / 3.0);
  double sphericalDisproportionMesh = meshSurf / 4 / pi / std::pow(3.0 / 4.0 / pi * meshVolume, 2.0 / 3.0);
  double sphericalDisproportionPixel = pixelSurface / 4 / pi / std::pow(3.0 / 4.0 / pi * pixelVolume, 2.0 / 3.0);
  double asphericity = std::pow(1.0/compactness2, (1.0 / 3.0)) - 1;
  double asphericityMesh = std::pow(1.0 / compactness2MeshMesh, (1.0 / 3.0)) - 1;
  double asphericityPixel = std::pow(1.0/compactness2Pixel, (1.0 / 3.0)) - 1;

  //Calculate center of mass shift
  int xx = mask->GetDimensions()[0];
  int yy = mask->GetDimensions()[1];
  int zz = mask->GetDimensions()[2];

  double xd = mask->GetGeometry()->GetSpacing()[0];
  double yd = mask->GetGeometry()->GetSpacing()[1];
  double zd = mask->GetGeometry()->GetSpacing()[2];

  vtkSmartPointer<vtkDoubleArray> dataset1Arr = vtkSmartPointer<vtkDoubleArray>::New();
  vtkSmartPointer<vtkDoubleArray> dataset2Arr = vtkSmartPointer<vtkDoubleArray>::New();
  vtkSmartPointer<vtkDoubleArray> dataset3Arr = vtkSmartPointer<vtkDoubleArray>::New();
  dataset1Arr->SetNumberOfComponents(1);
  dataset2Arr->SetNumberOfComponents(1);
  dataset3Arr->SetNumberOfComponents(1);
  dataset1Arr->SetName("M1");
  dataset2Arr->SetName("M2");
  dataset3Arr->SetName("M3");

  vtkSmartPointer<vtkDoubleArray> dataset1ArrU = vtkSmartPointer<vtkDoubleArray>::New();
  vtkSmartPointer<vtkDoubleArray> dataset2ArrU = vtkSmartPointer<vtkDoubleArray>::New();
  vtkSmartPointer<vtkDoubleArray> dataset3ArrU = vtkSmartPointer<vtkDoubleArray>::New();
  dataset1ArrU->SetNumberOfComponents(1);
  dataset2ArrU->SetNumberOfComponents(1);
  dataset3ArrU->SetNumberOfComponents(1);
  dataset1ArrU->SetName("M1");
  dataset2ArrU->SetName("M2");
  dataset3ArrU->SetName("M3");

  for (int x = 0; x < xx; x++)
  {
    for (int y = 0; y < yy; y++)
    {
      for (int z = 0; z < zz; z++)
      {
        itk::Image<int,3>::IndexType index;

        index[0] = x;
        index[1] = y;
        index[2] = z;

        mitk::ScalarType pxImage;
        mitk::ScalarType pxMask;

        mitkPixelTypeMultiplex5(
              mitk::FastSinglePixelAccess,
              image->GetChannelDescriptor().GetPixelType(),
              image,
              image->GetVolumeData(),
              index,
              pxImage,
              0);

        mitkPixelTypeMultiplex5(
              mitk::FastSinglePixelAccess,
              mask->GetChannelDescriptor().GetPixelType(),
              mask,
              mask->GetVolumeData(),
              index,
              pxMask,
              0);

        //Check if voxel is contained in segmentation
        if (pxMask > 0)
        {
          dataset1ArrU->InsertNextValue(x*xd);
          dataset2ArrU->InsertNextValue(y*yd);
          dataset3ArrU->InsertNextValue(z*zd);

          if (pxImage == pxImage)
          {
            dataset1Arr->InsertNextValue(x*xd);
            dataset2Arr->InsertNextValue(y*yd);
            dataset3Arr->InsertNextValue(z*zd);
          }
        }
      }
    }
  }

  vtkSmartPointer<vtkTable> datasetTable = vtkSmartPointer<vtkTable>::New();
  datasetTable->AddColumn(dataset1Arr);
  datasetTable->AddColumn(dataset2Arr);
  datasetTable->AddColumn(dataset3Arr);

  vtkSmartPointer<vtkTable> datasetTableU = vtkSmartPointer<vtkTable>::New();
  datasetTableU->AddColumn(dataset1ArrU);
  datasetTableU->AddColumn(dataset2ArrU);
  datasetTableU->AddColumn(dataset3ArrU);

  vtkSmartPointer<vtkPCAStatistics> pcaStatistics = vtkSmartPointer<vtkPCAStatistics>::New();
  pcaStatistics->SetInputData(vtkStatisticsAlgorithm::INPUT_DATA, datasetTable);
  pcaStatistics->SetColumnStatus("M1", 1);
  pcaStatistics->SetColumnStatus("M2", 1);
  pcaStatistics->SetColumnStatus("M3", 1);
  pcaStatistics->RequestSelectedColumns();
  pcaStatistics->SetDeriveOption(true);
  pcaStatistics->Update();

  vtkSmartPointer<vtkDoubleArray> eigenvalues = vtkSmartPointer<vtkDoubleArray>::New();
  pcaStatistics->GetEigenvalues(eigenvalues);

  pcaStatistics->SetInputData(vtkStatisticsAlgorithm::INPUT_DATA, datasetTableU);
  pcaStatistics->Update();
  vtkSmartPointer<vtkDoubleArray> eigenvaluesU = vtkSmartPointer<vtkDoubleArray>::New();
  pcaStatistics->GetEigenvalues(eigenvaluesU);

  std::vector<double> eigen_val(3);
  std::vector<double> eigen_valUC(3);
  eigen_val[2] = eigenvalues->GetValue(0);
  eigen_val[1] = eigenvalues->GetValue(1);
  eigen_val[0] = eigenvalues->GetValue(2);
  eigen_valUC[2] = eigenvaluesU->GetValue(0);
  eigen_valUC[1] = eigenvaluesU->GetValue(1);
  eigen_valUC[0] = eigenvaluesU->GetValue(2);

  double major = 4*sqrt(eigen_val[2]);
  double minor = 4*sqrt(eigen_val[1]);
  double least = 4*sqrt(eigen_val[0]);
  double elongation = (major == 0) ? 0 : sqrt(eigen_val[1] / eigen_val[2]);
  double flatness = (major == 0) ? 0 : sqrt(eigen_val[0] / eigen_val[2]);
  double majorUC = 4*sqrt(eigen_valUC[2]);
  double minorUC = 4*sqrt(eigen_valUC[1]);
  double leastUC = 4*sqrt(eigen_valUC[0]);
  double elongationUC = majorUC == 0 ? 0 : sqrt(eigen_valUC[1] / eigen_valUC[2]);
  double flatnessUC = majorUC == 0 ? 0 : sqrt(eigen_valUC[0] / eigen_valUC[2]);

  std::string prefix = FeatureDescriptionPrefix();
  featureList.push_back(std::make_pair(prefix + "Volume (mesh based)",meshVolume));
  featureList.push_back(std::make_pair(prefix + "Surface (mesh based)",meshSurf));
  featureList.push_back(std::make_pair(prefix + "Surface to volume ratio (mesh based)",surfaceToVolume));
  featureList.push_back(std::make_pair(prefix + "Sphericity (mesh based)",sphericity));
  featureList.push_back(std::make_pair(prefix + "Sphericity (mesh, mesh based)", sphericityMesh));
  featureList.push_back(std::make_pair(prefix + "Asphericity (mesh based)", asphericity));
  featureList.push_back(std::make_pair(prefix + "Asphericity (mesh, mesh based)", asphericityMesh));
  featureList.push_back(std::make_pair(prefix + "Compactness 1 (mesh based)", compactness3));
  featureList.push_back(std::make_pair(prefix + "Compactness 1 old (mesh based)" ,compactness1));
  featureList.push_back(std::make_pair(prefix + "Compactness 2 (mesh based)",compactness2));
  featureList.push_back(std::make_pair(prefix + "Compactness 1 (mesh, mesh based)", compactness3MeshMesh));
  featureList.push_back(std::make_pair(prefix + "Compactness 2 (mesh, mesh based)", compactness2MeshMesh));
  featureList.push_back(std::make_pair(prefix + "Spherical disproportion (mesh based)", sphericalDisproportion));
  featureList.push_back(std::make_pair(prefix + "Spherical disproportion (mesh, mesh based)", sphericalDisproportionMesh));
  featureList.push_back(std::make_pair(prefix + "Surface to volume ratio (voxel based)", surfaceToVolumePixel));
  featureList.push_back(std::make_pair(prefix + "Sphericity (voxel based)", sphericityPixel));
  featureList.push_back(std::make_pair(prefix + "Asphericity (voxel based)", asphericityPixel));
  featureList.push_back(std::make_pair(prefix + "Compactness 1 (voxel based)", compactness3Pixel));
  featureList.push_back(std::make_pair(prefix + "Compactness 1 old (voxel based)", compactness1Pixel));
  featureList.push_back(std::make_pair(prefix + "Compactness 2 (voxel based)", compactness2Pixel));
  featureList.push_back(std::make_pair(prefix + "Spherical disproportion (voxel based)", sphericalDisproportionPixel));
  featureList.push_back(std::make_pair(prefix + "PCA Major axis length",major));
  featureList.push_back(std::make_pair(prefix + "PCA Minor axis length",minor));
  featureList.push_back(std::make_pair(prefix + "PCA Least axis length",least));
  featureList.push_back(std::make_pair(prefix + "PCA Elongation",elongation));
  featureList.push_back(std::make_pair(prefix + "PCA Flatness",flatness));
  featureList.push_back(std::make_pair(prefix + "PCA Major axis length (uncorrected)", majorUC));
  featureList.push_back(std::make_pair(prefix + "PCA Minor axis length (uncorrected)", minorUC));
  featureList.push_back(std::make_pair(prefix + "PCA Least axis length (uncorrected)", leastUC));
  featureList.push_back(std::make_pair(prefix + "PCA Elongation (uncorrected)", elongationUC));
  featureList.push_back(std::make_pair(prefix + "PCA Flatness (uncorrected)", flatnessUC));

  return featureList;
}