[Olena-patches] 1801: Line gradient computation.

https://svn.lrde.epita.fr/svn/oln/trunk/milena Index: ChangeLog from Roland Levillain &lt;roland(a)lrde.epita.fr&gt; Line gradient computation. * tests/morpho/lena_line_graph_image_wst1.cc: Fix comments. * tests/morpho/lena_line_graph_image_wst2.cc: Fix the initialization of the watershed image. Reify and move the line gradient computation... * mln/morpho/line_gradient.hh: ...here (new file). mln/morpho/line_gradient.hh | 122 +++++++++++++++++++++++++++++ tests/morpho/lena_line_graph_image_wst1.cc | 9 -- tests/morpho/lena_line_graph_image_wst2.cc | 63 +------------- 3 files changed, 133 insertions(+), 61 deletions(-) Index: tests/morpho/lena_line_graph_image_wst1.cc --- tests/morpho/lena_line_graph_image_wst1.cc (revision 1800) +++ tests/morpho/lena_line_graph_image_wst1.cc (working copy) @@ -90,11 +90,8 @@ image2d<input_val_t> input; io::pgm::load(input, MLN_IMG_DIR "/tiny.pgm"); - /* FIXME: Don't compute a gradient on the image2d input. Instead, - have the values of the line graph image /behaves/ as the gradient - of the input, i.e., edges should hold the absolute difference - between gray levels. - */ + // In this test, the gradient is directly computed on the input + // image, not on the edges of the line graph image. image2d<input_val_t> gradient = morpho::gradient (input, convert::to_window(c4())); @@ -126,7 +123,7 @@ g.add_node (p); node_values.push_back (work(p)); /* FIXME: ``Guessing'' the id of the point just being inserted - is bad. utill:graph<N,E>::add_node should return this + is bad. util:graph<N,E>::add_node should return this id. */ points[p] = id; ++id; Index: tests/morpho/lena_line_graph_image_wst2.cc --- tests/morpho/lena_line_graph_image_wst2.cc (revision 1800) +++ tests/morpho/lena_line_graph_image_wst2.cc (working copy) @@ -62,7 +62,7 @@ #include <mln/core/line_graph_elt_neighborhood.hh> #include <mln/core/line_graph_neighborhood_piter.hh> -#include <mln/morpho/gradient.hh> +#include <mln/morpho/line_gradient.hh> #include <mln/morpho/closing_area.hh> #include <mln/morpho/meyer_wst.hh> #include <mln/level/stretch.hh> @@ -98,57 +98,13 @@ image2d<input_val_t> input; io::pgm::load(input, MLN_IMG_DIR "/small.pgm"); - /*-------------. - | Line graph. | - `-------------*/ - - // FIXME: Inlined conversion, to be reifed into a routine. - - util::graph<point2d> g; - - // Points. - /* FIXME: The need for such a structure during the conversion - exhibits the lack of a service from util::graph (or a another, - missing tool) regarding the retrieval of nodes' ids from - points. */ - std::map<point2d, util::node_id> points; - util::node_id id = 0; - - // Nodes. - std::vector<input_val_t> node_values; - mln_fwd_piter_(image2d<input_val_t>) p(input.domain()); - for_all (p) - { - g.add_node (p); - node_values.push_back (input(p)); - /* FIXME: ``Guessing'' the id of the point just being inserted - is bad. utill:graph<N,E>::add_node should return this - id. */ - points[p] = id; - ++id; - } - - // Edges. - window2d next_c4_win; - next_c4_win.insert(0, 1).insert(1, 0); - std::vector<input_val_t> edge_values; - mln_fwd_qiter_(window2d) q(next_c4_win, p); - for_all (p) - for_all (q) - if (input.has(q)) - { - g.add_edge(points[p], points[q]); - // The computed value is a kind of norm of the gradient - // bewteen P and Q. - edge_values.push_back(math::abs(input(p) - input(q))); - } - - // Line graph point set. - p_line_graph<point2d> plg(g); + /*----------------. + | Line gradient. | + `----------------*/ // Line graph image. typedef line_graph_image<point2d, input_val_t> ima_t; - ima_t lg_ima(plg, node_values, edge_values); + ima_t lg_ima = morpho::line_gradient(input); /*-----------------. | Simplification. | @@ -180,10 +136,8 @@ // Reduce the value set to 8-bit. typedef int_u8 wst_val_t; typedef line_graph_image<point2d, wst_val_t> wst_ima_t; - // FIXME: Initializations should not be that complicated. - wst_ima_t wshed (plg, - std::vector<wst_val_t>(node_values.size()), - std::vector<wst_val_t>(edge_values.size())); + wst_ima_t wshed; + initialize(wshed, wshed_full); level::stretch(wshed_full, wshed); /*---------. @@ -202,7 +156,7 @@ input.domain().pmax()[1] * 2); output_t output(box2d(output_pmin, output_pmax)); level::fill(output, literal::black); - // Reuse the piter on INPUT. + mln_fwd_piter_(image2d<input_val_t>) p(input.domain()); for_all(p) { // Equivalent of P in OUTPUT. @@ -214,7 +168,6 @@ } // Interpolate missing points in OUTPUT. mln_piter_(output_t) p_out(output.domain()); -// mln_niter_(neighb2d) n_out(c4(), p_out); for_all(p_out) { // Process points on even rows and odd columns Index: mln/morpho/line_gradient.hh --- mln/morpho/line_gradient.hh (revision 0) +++ mln/morpho/line_gradient.hh (revision 0) @@ -0,0 +1,122 @@ +// Copyright (C) 2008 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_MORPHO_LINE_GRADIENT_HH +# define MLN_MORPHO_LINE_GRADIENT_HH + +/// \file mln/morpho/line_gradient.hh +/// \brief Conversions to mln::line_graph_image. + +# include <map> +# include <vector> + +# include <mln/core/image2d.hh> +# include <mln/core/line_graph_image.hh> + +// FIXME: Generalize to other (input) images as well (image1d, +// image3d, etc.). + +namespace mln +{ + + namespace morpho + { + + /// \brief Create a line graph image representing the gradient + /// norm of a mln::image2d. + /* FIXME: Currently, the adjacency is set to 4-c and cannot be + changed. */ + template <typename T> + mln::line_graph_image<mln::point2d, T> + line_gradient(const mln::image2d<T>& ima); + + +# ifndef MLN_INCLUDE_ONLY + + template <typename T> + mln::line_graph_image<mln::point2d, T> + line_gradient(const mln::image2d<T>& ima) + { + // FIXME: Precondition: Ensure the image is scalar. + typedef T value_t; + + util::graph<mln::point2d> g; + + // Points. + /* FIXME: The need for such a structure during the conversion + exhibits the lack of a service from util::graph (or a another, + missing tool) regarding the retrieval of nodes' ids from + points. */ + std::map<mln::point2d, util::node_id> points; + util::node_id id = 0; + + // Nodes. + std::vector<value_t> node_values; + mln_fwd_piter(image2d<value_t>) p(ima.domain()); + for_all (p) + { + g.add_node (p); + node_values.push_back (ima(p)); + /* FIXME: ``Guessing'' the id of the point just being inserted + is bad. util:graph<N,E>::add_node should return this + id. */ + points[p] = id; + ++id; + } + + // Edges. + // FIXME: The creation of this window should be generic. + window2d next_c4_win; + next_c4_win.insert(0, 1).insert(1, 0); + std::vector<value_t> edge_values; + mln_fwd_qiter_(window2d) q(next_c4_win, p); + for_all (p) + for_all (q) + if (ima.has(q)) + { + g.add_edge(points[p], points[q]); + // The computed value is a norm of the gradient between P and Q. + edge_values.push_back(math::abs(ima(p) - ima(q))); + } + + // Line graph point set. + p_line_graph<mln::point2d> plg(g); + + // Line graph image. + typedef line_graph_image<mln::point2d, value_t> ima_t; + ima_t lg_ima(plg, node_values, edge_values); + return lg_ima; + } + +# endif // ! MLN_INCLUDE_ONLY + + } // end of namespace mln::morpho + +} // end of namespace mln + + +#endif // ! MLN_MORPHO_LINE_GRADIENT_HH