URL: https://svn.lrde.epita.fr/svn/oln/trunk/milena ChangeLog: 2007-09-06 Simon Nivault <simon.nivault@lrde.epita.fr> Median specialized for fast image * sandbox/nivault/median.hh: New. median.hh | 215 ++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++ 1 file changed, 215 insertions(+) Index: trunk/milena/sandbox/nivault/median.hh =================================================================== --- trunk/milena/sandbox/nivault/median.hh (revision 0) +++ trunk/milena/sandbox/nivault/median.hh (revision 1074) @@ -0,0 +1,215 @@ +// Copyright (C) 2007 EPITA Research and Development Laboratory +// +// 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_LEVEL_MEDIAN_HH +# define MLN_LEVEL_MEDIAN_HH + +/*! \file mln/level/median.hh + * + * \brief Median filtering of an image. + */ + +# include <mln/core/concept/image.hh> +# include <mln/geom/size2d.hh> + +# include <mln/core/window2d.hh> +# include <mln/core/win/hline2d.hh> +# include <mln/core/t_image.hh> + +# include <mln/accu/median.hh> +# include <mln/canvas/sbrowsing.hh> + +# include <mln/geom/shift.hh> +# include <mln/set/diff.hh> + + +namespace mln +{ + + namespace level + { + + /*! Compute in \p output the median filter of image \p input by + * the window \p win. + * + * \param[in] input The image to be filtered. + * \param[in] win The window. + * \param[in,out] output The output image. + * + * \pre \p input and \p output have to be initialized. + */ + template <typename I, typename W, typename O> + void median(const Image<I>& input, const Window<W>& win, + Image<O>& output); + + +# ifndef MLN_INCLUDE_ONLY + + + namespace impl + { + + + template <typename I, typename O> + void median(const Image<I>& input_, const win::hline2d& win, O& output) + { + + I& input = exact(input_); + typedef mln_coord(I) coord; + const coord + min_row = geom::min_row(input), + max_row = geom::max_row(input), + min_col = geom::min_col(input), + max_col = geom::max_col(input); + const coord half = win.length() / 2; + + point2d p; + coord& row = p.row(); + coord& col = p.col(); + + point2d pt; + coord& ct = pt.col(); + + point2d pu; + coord& cu = pu.col(); + + accu::median<mln_vset(I)> med(input.values()); + + for (row = min_row; row <= max_row; ++row) + { + pt.row() = pu.row() = row; + + // initialization (before first point of the row) + med.init(); + for (ct = min_col; ct < min_col + half; ++ct) + med.take(input(pt)); + + // left columns (just take new points) + for (col = min_col; col <= min_col + half; ++col, ++ct) + { + med.take(input(pt)); + output(p) = med.to_value(); + } + + // middle columns (both take and untake) + cu = min_col; + for (; col <= max_col - half; ++cu, ++col, ++ct) + { + med.take(input(pt)); + med.untake(input(pu)); + output(p) = med.to_value(); + } + + // right columns (now just untake old points) + for (; col <= max_col; ++cu, ++col) + { + med.untake(input(pu)); + output(p) = med.to_value(); + } + } + } + + template <typename I, typename O> + void median(const Fast_Image<I>& input_, const win::hline2d& win, O& output) + { + + I& input = exact(input_); + border::resize(input, win.delta());; + border::duplicate(input); + + typedef mln_coord(I) coord; + const coord + min_row = geom::min_row(input), + max_row = geom::max_row(input), + min_col = geom::min_col(input), + max_col = geom::max_col(input); + const coord half = win.length() / 2; + + point2d p; + coord& row = p.row(); + coord& col = p.col(); + + point2d pt; + coord& ct = pt.col(); + + point2d pu; + coord& cu = pu.col(); + + accu::median<mln_vset(I)> med(input.values()); + + for (row = min_row; row <= max_row; ++row) + { + pt.row() = pu.row() = row; + + // initialization (before first point of the row) + med.init(); + for (ct = min_col - half; ct < min_col + half; ++ct) + med.take(input(pt)); + + // middle columns (both take and untake) + cu = min_col; + for (col = min_col; col <= max_col; ++cu, ++col, ++ct) + { + med.take(input(pt)); + med.untake(input(pu)); + output(p) = med.to_value(); + } + + } + } + + template <typename I, typename O> + void median(const I& input, const win::vline2d& win, O& output) + { + t_image<O> swap_output = swap_coords(output, 0, 1); + impl::median(swap_coords(input, 0, 1), + win::hline2d(win.length()), + swap_output); + } + + + } // end of namespace mln::level::impl + + + // facade + + template <typename I, typename W, typename O> + void median(const Image<I>& input, const Window<W>& win, + Image<O>& output) + { + mln_assertion(exact(output).domain() == exact(input).domain()); + impl::median(exact(input), exact(win), exact(output)); + } + +# endif // ! MLN_INCLUDE_ONLY + + } // end of namespace mln::level + +} // end of namespace mln + + +#endif // ! MLN_LEVEL_MEDIAN_HH