gaussian_1d.hh

// Copyright (C) 2009 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_LINEAR_GAUSSIAN_1D_HH
# define MLN_LINEAR_GAUSSIAN_1D_HH


#include <mln/core/image/image1d.hh>
#include <mln/linear/gaussian_directional_2d.hh>



namespace mln
{

  namespace linear
  {


    template <typename I>
    mln_concrete(I)
    gaussian_1d(const Image<I>& input,
                double sigma,
                const mln_value(I)& bdr);



# ifndef MLN_INCLUDE_ONLY

    template <typename I>
    inline
    mln_concrete(I)
    gaussian_1d(const Image<I>& input_,
                double sigma,
                const mln_value(I)& bdr)
    {
      trace::entering("linear::gaussian_1d");

      typedef mln_site(I) P;
      mlc_bool(P::dim == 1)::check();

      const I& input = exact(input_);
      mln_precondition(input.is_valid());

      my::recursivefilter_coef_ coef(1.68f, 3.735f,
                                     1.783f, 1.723f,
                                     -0.6803f, -0.2598f,
                                     0.6318f, 1.997f,
                                     sigma,
                                     my::recursivefilter_coef_::DericheGaussian);

      extension::adjust_fill(input, 5 * int(sigma + .50001) + 1, bdr);
      mln_concrete(I) output = duplicate(input);

      if (sigma < 0.006)
        return output;

      int
        ninds = geom::ninds(input),
        b     = input.border();

      recursivefilter_directional_fastest(output, coef,
                                          point1d(- b),
                                          point1d(ninds - 1 + b),
                                          ninds + 2 * b,
                                          dpoint1d(1),
                                          bdr);

      trace::exiting("linear::gaussian_1d");
      return output;
    }

# endif // ! MLN_INCLUDE_ONLY

  } // end of namespace mln::linear

} // end of namespace mln


#endif // ! MLN_LINEAR_GAUSSIAN_1D_HH