Esempio n. 1
0
void run() {

  Image::Header input_SH_header (argument[0]);
  if (input_SH_header.ndim() != 4)
    throw Exception ("input SH image should contain 4 dimensions");
  std::vector<ssize_t> strides (4, 0);
  strides[3] = 1;
  Image::BufferPreload<value_type> input_buf (input_SH_header, strides);

  Math::Vector<value_type> responseSH;
  responseSH.load (argument[1]);
  Math::Vector<value_type> responseRH;
  Math::SH::SH2RH (responseRH, responseSH);

  Ptr<Image::Buffer<bool> > mask_buf;
  Options opt = get_options ("mask");
  if (opt.size()) {
    mask_buf = new Image::Buffer<bool> (opt[0][0]);
    Image::check_dimensions (*mask_buf, input_buf, 0, 3);
  }

  Image::Header output_SH_header (input_SH_header);
  Image::Stride::set_from_command_line (output_SH_header, Image::Stride::contiguous_along_axis (3));
  Image::Buffer<value_type> output_SH_buf (argument[2], output_SH_header);

  SDeconvFunctor sconv (input_buf, output_SH_buf, mask_buf, responseRH);
  Image::ThreadedLoop loop ("performing convolution...", input_buf, 2, 0, 3);
  loop.run (sconv);
}
Esempio n. 2
0
void run ()
{
  Image::Buffer<value_type> dwi_data (argument[0]);

  if (dwi_data.ndim() != 4)
    throw Exception ("dwi image should contain 4 dimensions");

  Math::Matrix<value_type> grad = DWI::get_valid_DW_scheme<value_type> (dwi_data);
  DWI::Shells shells (grad);
  // Keep the b=0 shell (may be used for normalisation), but force single non-zero shell
  shells.select_shells (true, true);

  Math::Matrix<value_type> DW_dirs = DWI::gen_direction_matrix (grad, shells.largest().get_volumes());

  Options opt = get_options ("lmax");
  lmax = opt.size() ? opt[0][0] : Math::SH::LforN (shells.largest().count());
  INFO ("calculating even spherical harmonic components up to order " + str (lmax));

  Math::Matrix<value_type> HR_dirs;
  Math::Matrix<value_type> HR_SHT;
  opt = get_options ("normalise");
  if (opt.size()) {
    normalise = true;
    opt = get_options ("directions");
    if (opt.size())
      HR_dirs.load (opt[0][0]);
    else
      DWI::Directions::electrostatic_repulsion_300 (HR_dirs);
    Math::SH::init_transform (HR_SHT, HR_dirs, lmax);
  }

  // set Lmax
  int i;
  for (i = 0; Math::SH::NforL(i) < shells.largest().count(); i += 2);
  i -= 2;
  if (lmax > i) {
    WARN ("not enough data for SH order " + str(lmax) + ", falling back to " + str(i));
    lmax = i;
  }
  INFO("setting maximum even spherical harmonic order to " + str(lmax));

  // Setup response function
  int num_RH = (lmax + 2)/2;
  Math::Vector<value_type> sigs(num_RH);
  std::vector<value_type> AL (lmax+1);
  Math::Legendre::Plm_sph<value_type>(&AL[0], lmax, 0, 0);
  for (int l = 0; l <= lmax; l += 2) sigs[l/2] = AL[l];
  Math::Vector<value_type> response(num_RH);
  Math::SH::SH2RH(response, sigs);

  opt = get_options ("filter");
  Math::Vector<value_type> filter;
  if (opt.size()) {
    filter.load (opt[0][0]);
    if (filter.size() <= response.size())
      throw Exception ("not enough filter coefficients supplied for lmax" + str(lmax));
    for (int i = 0; i <= lmax/2; i++) response[i] *= filter[i];
    INFO ("using initial filter coefficients: " + str (filter));
  }

  Math::SH::Transform<value_type> FRT_SHT(DW_dirs, lmax);
  FRT_SHT.set_filter(response);

  Image::Header qbi_header (dwi_data);
  qbi_header.dim(3) = Math::SH::NforL (lmax);
  qbi_header.datatype() = DataType::Float32;
  Image::Stride::set (qbi_header, Image::Stride::contiguous_along_axis (3, dwi_data));
  Image::Buffer<value_type> qbi_data (argument[1], qbi_header);


  opt = get_options ("mask");
  if (opt.size()) {
    Image::Buffer<bool> mask_data (opt[0][0]);
    Image::ThreadedLoop ("estimating dODFs using Q-ball imaging...", dwi_data, 0, 3)
      .run (DWI2QBI (FRT_SHT.mat_A2SH(), HR_SHT, shells), mask_data.voxel(), dwi_data.voxel(), qbi_data.voxel());
  }
  else 
    Image::ThreadedLoop ("estimating dODFs using Q-ball imaging...", dwi_data, 0, 3)
      .run (DWI2QBI (FRT_SHT.mat_A2SH(), HR_SHT, shells), dwi_data.voxel(), qbi_data.voxel());
}