crest.hh

// Copyright (C) 2009, 2010, 2011 EPITA Research and Development
// Laboratory (LRDE)
//
// This file is part of Olena.
//
// Olena is free software: you can redistribute it and/or modify it under
// the terms of the GNU General Public License as published by the Free
// Software Foundation, version 2 of the License.
//
// Olena is distributed in the hope that it will be useful,
// but WITHOUT ANY WARRANTY; without even the implied warranty of
// MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the GNU
// General Public License for more details.
//
// You should have received a copy of the GNU General Public License
// along with Olena.  If not, see <http://www.gnu.org/licenses/>.
//
// As a special exception, you may use this file as part of a free
// software project without restriction.  Specifically, if other files
// instantiate templates or use macros or inline functions from this
// file, or you compile this file and link it with other files to produce
// an executable, this file does not by itself cause the resulting
// executable to be covered by the GNU General Public License.  This
// exception does not however invalidate any other reasons why the
// executable file might be covered by the GNU General Public License.

#ifndef MLN_TOPO_SKELETON_CREST_HH
# define MLN_TOPO_SKELETON_CREST_HH


# include <mln/core/concept/image.hh>
# include <mln/core/concept/neighborhood.hh>
# include <mln/data/fill.hh>
# include <mln/extension/adjust.hh>
# include <mln/border/equalize.hh>


namespace mln
{

  namespace topo
  {

    namespace skeleton
    {


      //
      template <typename I, typename D, typename N>
      mln_concrete(I)
      crest(const Image<I>& input, const Image<D>& dist_map,
            const Neighborhood<N>& nbh, unsigned psi_threshold);

      template <typename I, typename D, typename N>
      mln_concrete(I)
      crest(const Image<I>& input, const Image<D>& dist_map,
            const Neighborhood<N>& nbh);



# ifndef MLN_INCLUDE_ONLY

      // IMPLEMENTATIONS

      namespace impl
      {

        namespace generic
        {

          template <typename I, typename D, typename N>
          mln_concrete(I)
          crest(const Image<I>& input_, const Image<D>& dist_map_,
                const Neighborhood<N>& nbh_, unsigned psi_threshold)
          {
            trace::entering("topo::skeleton::impl::generic::crest");
            const I& input = exact(input_);
            const D& dist_map = exact(dist_map_);
            const N& nbh = exact(nbh_);

            mlc_equal(mln_value(I), bool)::check();
            mln_precondition(input.is_valid());
            mln_precondition(dist_map.is_valid());
            mln_precondition(nbh.is_valid());

            mln_concrete(I) is_crest;
            initialize(is_crest, input);
            data::fill(is_crest, false);

            mln_piter(I) p(input.domain());
            mln_niter(N) n(nbh, p);
            for_all(p)
            {
              if (!input(p) || dist_map(p) < static_cast<mln_value(D)>(0))
                continue;

              unsigned nb_eq = 0;
              unsigned nb_lt = 0;
              for_all(n)
                if (input.domain().has(n)
                    // We want to only consider sites which are part of
                    // the skeleton. If this test is removed, sometimes
                    // edge sites are considered as sites with a high PSI
                    // which is wrong.
                    && dist_map(n) > static_cast<mln_value(D)>(0))
                {
                  if (dist_map(n) == dist_map(p))
                    ++nb_eq;
                  else if (dist_map(n) < dist_map(p))
                    ++nb_lt;
                }

              if ((nb_lt + nb_eq) >= psi_threshold) // Pixel Superiority index
                is_crest(p) = true;
            }

            trace::exiting("topo::skeleton::impl::generic::crest");
            return is_crest;
          }

        } // end of namespace mln::topo::skeleton::impl::generic




        template <typename I, typename D, typename N>
        mln_concrete(I)
        crest_fastest_2d(const Image<I>& input_, const Image<D>& dist_map_,
                         const Neighborhood<N>& nbh_, unsigned psi_threshold)
        {
          trace::entering("topo::skeleton::impl::crest_fastest_2d");

          const I& input = exact(input_);
          const D& dist_map = exact(dist_map_);
          const N& nbh = exact(nbh_);

          mlc_equal(mln_value(I), bool)::check();
          mln_precondition(input.is_valid());
          mln_precondition(dist_map.is_valid());
          mln_precondition(nbh.is_valid());
          mln_precondition(input.domain() == dist_map.domain());

          extension::adjust(input, nbh);
          border::equalize(input, dist_map, input.border());

          mln_concrete(I) is_crest;
          initialize(is_crest, input);
          data::fill(is_crest, false);


          mln_pixter(const I) p(input);
          util::array<int> dp = mln::offsets_wrt(input, nbh);
          unsigned n_nbhs = dp.nelements();
          for_all(p)
          {
            if (!p.val()
                || dist_map.element(p) < static_cast<mln_value(D)>(0))
              continue;

            unsigned nb_eq = 0;
            unsigned nb_lt = 0;
            for (unsigned i = 0; i < n_nbhs; ++i)
            {
              unsigned n = p.offset() + dp[i];
              if (// We want to only consider sites which are part of
                  // the skeleton. If this test is removed, sometimes
                  // edge sites are considered as sites with a high PSI
                  // which is wrong.
                dist_map.element(n) > static_cast<mln_value(D)>(0))
              {
                if (dist_map.element(n) == dist_map.element(p))
                  ++nb_eq;
                else if (dist_map.element(n) < dist_map.element(p))
                  ++nb_lt;
              }

              if ((nb_lt + nb_eq) >= psi_threshold) // Pixel Superiority index
                is_crest.element(p) = true;
            }

          }

          trace::exiting("topo::skeleton::impl::crest_fastest_2d");
          return is_crest;
        }

      } // end of namespace mln::topo::skeleton::impl


      // DISPATCH

      namespace internal
      {

        template <typename I, typename D, typename N>
        mln_concrete(I)
        crest_dispatch_2d(mln::trait::image::value_storage::any,
                          mln::trait::image::value_access::any,
                          mln::trait::image::ext_domain::any,
                          const Image<I>& input, const Image<D>& dist_map,
                          const Neighborhood<N>& nbh, unsigned psi_threshold)
        {
          return skeleton::impl::generic::crest(input, dist_map,
                                                nbh, psi_threshold);
        }


        template <typename I, typename D, typename N>
        mln_concrete(I)
        crest_dispatch_2d(mln::trait::image::value_storage::one_block,
                          mln::trait::image::value_access::direct,
                          mln::trait::image::ext_domain::some,
                          const Image<I>& input, const Image<D>& dist_map,
                          const Neighborhood<N>& nbh, unsigned psi_threshold)
        {
          return skeleton::impl::crest_fastest_2d(input, dist_map,
                                                  nbh, psi_threshold);
        }


        template <typename I, typename D, typename N>
        mln_concrete(I)
        crest_dispatch(const Image<I>& input, const Image<D>& dist_map,
              const Neighborhood<N>& nbh, unsigned psi_threshold)
        {
          unsigned dim = mln_site_(I)::dim;

          if (dim == 2)
            return
              crest_dispatch_2d(mln_trait_image_value_storage(I)(),
                                mln_trait_image_value_access(I)(),
                                mln_trait_image_ext_domain(I)(),
                                input, dist_map, nbh, psi_threshold);

          return impl::generic::crest(input, dist_map, nbh, psi_threshold);
        }


      } // end of namespace mln::topo::skeleton::internal


      // FACADES

      template <typename I, typename D, typename N>
      mln_concrete(I)
      crest(const Image<I>& input, const Image<D>& dist_map,
            const Neighborhood<N>& nbh, unsigned psi_threshold)
      {
        trace::entering("topo::skeleton::crest");

        mlc_equal(mln_value(I), bool)::check();
        mln_precondition(exact(input).is_valid());
        mln_precondition(exact(dist_map).is_valid());
        mln_precondition(exact(nbh).is_valid());

        mln_concrete(I)
          output = internal::crest_dispatch(input, dist_map,
                                            nbh, psi_threshold);

        trace::exiting("topo::skeleton::crest");
        return output;
      }


      template <typename I, typename D, typename N>
      mln_concrete(I)
      crest(const Image<I>& input, const Image<D>& dist_map,
            const Neighborhood<N>& nbh)
      {
        return crest(input, dist_map, nbh, 6);
      }

# endif // ! MLN_INCLUDE_ONLY


    } // end of namespace mln::topo::skeleton

  } // end of namespace mln::topo

} // end of namespace mln

#endif // ! MLN_TOPO_SKELETON_CREST_HH