[Olena-patches] milena r3371: Add n_max() function to compute n maxima in an array

URL: https://svn.lrde.epita.fr/svn/oln/trunk/milena ChangeLog: 2009-02-13 Fabien Freling &lt;fabien.freling(a)lrde.epita.fr&gt; Add n_max() function to compute n maxima in an array. * mln/labeling/n_max.hh: Implement the n_max() function. --- n_max.hh | 90 +++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++ 1 file changed, 90 insertions(+) Index: trunk/milena/mln/labeling/n_max.hh =================================================================== --- trunk/milena/mln/labeling/n_max.hh (revision 0) +++ trunk/milena/mln/labeling/n_max.hh (revision 3371) @@ -0,0 +1,90 @@ +// Copyright (C) 2009 EPITA Research and Development Laboratory (LRDE) +// +// This file is part of the Olena Library. This library is free +// software; you can redistribute it and/or modify it under the terms +// of the GNU General Public License version 2 as published by the +// Free Software Foundation. +// +// This library 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 this library; see the file COPYING. If not, write to +// the Free Software Foundation, 51 Franklin Street, Fifth Floor, +// Boston, MA 02111-1307, USA. +// +// As a special exception, you may use this file as part of a free +// software library 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_LABELING_N_MAX_HH +# define MLN_LABELING_N_MAX_HH + +# include <mln/core/concept/image.hh> +# include <mln/util/array.hh> + +/// \file mln/labeling/mean_values.hh +/// +/// Construct from a count accumulator of a labeled image an array with +/// the ordered n biggest labels +/// +/// \return an array starting at index 1 + + +namespace mln +{ + + namespace labeling + { + + template <typename L, typename V> + util::array<L> + n_max(const util::array<V>& in_arr, unsigned n); + + +# ifndef MLN_INCLUDE_ONLY + + template <typename L, typename V> + util::array<L> + n_max(const util::array<V>& in_arr, unsigned n) + { + trace::entering("mln::labeling::n_max"); + + util::array<L> output(n + 1, 0); + + int swap = 0; + for (unsigned i = 0; i < in_arr.nelements(); ++i) + { + if (in_arr[i] > in_arr[output[n]]) + { + output[n] = i; + } + int j = n - 1; + while (j > 0 && in_arr[output[j]] < in_arr[output[j + 1]]) + { + swap = output[j]; + output[j] = output[j + 1]; + output[j + 1] = swap; + --j; + } + } + + trace::exiting("mln::labeling::n_max"); + return output; + } + +# endif // !MLN_INCLUDE_ONLY + + } // end of namespace mln::labeling + +} // end of namespace mln + +#endif // ! MLN_LABELING_N_MAX_HH