URL: https://svn.lrde.epita.fr/svn/oln/branches/cleanup-2008/milena/sandbox ChangeLog: 2008-10-29 Matthieu Garrigues <garrigues@lrde.epita.fr> Add simple point computation to ocr preprocessing. * garrigues/ocr/simple_point.hh: New ,Tell if a point is simple or not. A point of an object is simple if in its c8 neiborhood, there is exactly one connected component of the object, and only one connected component of the background Examples : ( | == object, - = background) - - | | P | Here P is simple in the c4 and c8 case. | | | - | - | P | Here P is never simple. | | | * garrigues/ocr/simple_point.cc: New. A simple test that shows all the simple points of a binary image. --- simple_point.cc | 39 +++++++++++++ simple_point.hh | 165 ++++++++++++++++++++++++++++++++++++++++++++++++++++++++ 2 files changed, 204 insertions(+) Index: branches/cleanup-2008/milena/sandbox/garrigues/ocr/simple_point.hh =================================================================== --- branches/cleanup-2008/milena/sandbox/garrigues/ocr/simple_point.hh (revision 0) +++ branches/cleanup-2008/milena/sandbox/garrigues/ocr/simple_point.hh (revision 2728) @@ -0,0 +1,165 @@ +// Copyright (C) 2007, 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_SIMPLE_POINT_HH +# define MLN_SIMPLE_POINT_HH + +/*! \file simple_point.hh + * + * \brief simple_point tell if a point is simple or not (Cf + * bertrand.07.chap). + * + */ + +#include <mln/core/alias/point2d.hh> +#include <mln/core/image/image2d.hh> +#include <mln/core/alias/neighb2d.hh> + +namespace mln +{ + +/*! Tell if a point is simple or not. A point of an object is simple + * if in its c8 neiborhood, there is exactly one connected component of the + * object, and only one connected component of the background + * Examples : ( | == object, - = background) + * + * - - | + * | P | Here p is simple in the c4 and c8 case. + * | | | + * + * - | - + * | P | Here p is never simple. + * | | | + * + */ + + bool simple_point(const image2d<bool>& ima, const neighb2d& nbh, const point2d& p); + + unsigned nb_connexity2d(const image2d<bool>& ima, const neighb2d& nbh, const point2d& p); + +# ifndef MLN_INCLUDE_ONLY + + static const unsigned char nb_connexity_c8[256] = + { + 0, 1, 1, 1, 1, 2, 1, 1, 1, 1, 1, 1, 2, 2, 1, 1, + 1, 2, 1, 1, 1, 2, 1, 1, 2, 2, 1, 1, 2, 2, 1, 1, + 1, 2, 2, 2, 2, 3, 2, 2, 1, 1, 1, 1, 2, 2, 1, 1, + 2, 3, 2, 2, 2, 3, 2, 2, 2, 2, 1, 1, 2, 2, 1, 1, + + 1, 2, 2, 2, 2, 3, 2, 2, 1, 1, 1, 1, 2, 2, 1, 1, + 1, 2, 1, 1, 1, 2, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, + 1, 2, 2, 2, 2, 3, 2, 2, 1, 1, 1, 1, 2, 2, 1, 1, + 1, 2, 1, 1, 1, 2, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, + + 1, 2, 2, 2, 2, 3, 2, 2, 2, 2, 2, 2, 3, 3, 2, 2, + 1, 2, 1, 1, 1, 2, 1, 1, 2, 2, 1, 1, 2, 2, 1, 1, + 2, 3, 3, 3, 3, 4, 3, 3, 2, 2, 2, 2, 3, 3, 2, 2, + 2, 3, 2, 2, 2, 3, 2, 2, 2, 2, 1, 1, 2, 2, 1, 1, + + 1, 2, 2, 2, 2, 3, 2, 2, 1, 1, 1, 1, 2, 2, 1, 1, + 1, 2, 1, 1, 1, 2, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, + 1, 2, 2, 2, 2, 3, 2, 2, 1, 1, 1, 1, 2, 2, 1, 1, + 1, 2, 1, 1, 1, 2, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1 + }; + + static const unsigned char nb_connexity_c4[256] = + { + 0, 1, 1, 1, 1, 2, 1, 1, 1, 1, 2, 1, 2, 2, 2, 1, + 1, 2, 2, 2, 1, 2, 1, 1, 2, 2, 3, 2, 2, 2, 2, 1, + 1, 2, 2, 2, 2, 3, 2, 2, 1, 1, 2, 1, 2, 2, 2, 1, + 2, 3, 3, 3, 2, 3, 2, 2, 2, 2, 3, 2, 2, 2, 2, 1, + + 1, 2, 2, 2, 2, 3, 2, 2, 2, 2, 3, 2, 3, 3, 3, 2, + 2, 3, 3, 3, 2, 3, 2, 2, 3, 3, 4, 3, 3, 3, 3, 2, + 1, 2, 2, 2, 2, 3, 2, 2, 1, 1, 2, 1, 2, 2, 2, 1, + 2, 3, 3, 3, 2, 3, 2, 2, 2, 2, 3, 2, 2, 2, 2, 1, + + 1, 2, 2, 2, 2, 3, 2, 2, 2, 2, 3, 2, 3, 3, 3, 2, + 1, 2, 2, 2, 1, 2, 1, 1, 2, 2, 3, 2, 2, 2, 2, 1, + 2, 3, 3, 3, 3, 4, 3, 3, 2, 2, 3, 2, 3, 3, 3, 2, + 2, 3, 3, 3, 2, 3, 2, 2, 2, 2, 3, 2, 2, 2, 2, 1, + + 1, 2, 2, 2, 2, 3, 2, 2, 2, 2, 3, 2, 3, 3, 3, 2, + 1, 2, 2, 2, 1, 2, 1, 1, 2, 2, 3, 2, 2, 2, 2, 1, + 1, 2, 2, 2, 2, 3, 2, 2, 1, 1, 2, 1, 2, 2, 2, 1, + 1, 2, 2, 2, 1, 2, 1, 1, 1, 1, 2, 1, 1, 1, 1, 1 + }; + + neighb2d int_to_neighb(unsigned i) + { + if (i == 8) + return c8(); + if (i == 4) + return c4(); + mln_assertion(0); + return c4(); + } + + unsigned complement_neighb(unsigned i) + { + if (i == 8) + return 4; + if (i == 4) + return 8; + mln_assertion(0); + return 0; + } + + unsigned nb_connexity2d(const image2d<bool>& ima, unsigned nbh, const point2d& p, bool complemented) + { + unsigned res = 0; + + mln_fwd_niter_(neighb2d) n(c8() , p); + for_all(n) + { + res = (res << 1); + if (ima(n) == complemented) + res = res | 1; + } + + if (nbh == 8) + return nb_connexity_c8[res]; + else + { + mln_assertion(nbh == 4); + return nb_connexity_c4[res]; + } + } + + bool simple_point2d(const image2d<bool>& ima, unsigned nbh, const point2d& p) + { + mln_assertion(nbh == 4 || nbh == 8); + + return nb_connexity2d(ima, nbh, p, true) == 1 && + nb_connexity2d(ima, complement_neighb(nbh), p, false) == 1; + } + +# endif // MLN_INCLUDE_ONLY + +} // end of namespace mln + +#endif // ! MLN_SIMPLE_POINT_HH Index: branches/cleanup-2008/milena/sandbox/garrigues/ocr/simple_point.cc =================================================================== --- branches/cleanup-2008/milena/sandbox/garrigues/ocr/simple_point.cc (revision 0) +++ branches/cleanup-2008/milena/sandbox/garrigues/ocr/simple_point.cc (revision 2728) @@ -0,0 +1,39 @@ +# include <mln/core/image/image2d.hh> +# include <mln/io/pbm/load.hh> +# include <mln/io/pbm/save.hh> +# include <mln/level/fill.hh> + +# include "simple_point.hh" + + +void usage(char* argv[]) +{ + std::cerr << "usage: " << argv[0] << " input.pbm output.pbm" << std::endl; + abort(); +} + + + +int main(int argc, char* argv[]) +{ + using namespace mln; + using value::int_u8; + + if (argc != 3) + usage(argv); + + typedef image2d<bool> I; + I input; + io::pbm::load(input, argv[1]); + + I output; + initialize(output, input); + level::fill(output, false); + + mln_piter_(I) p(input.domain()); + for_all(p) + if (input(p) && simple_point2d(input, 8, p)) + output(p) = true; + + io::pbm::save(output, argv[2]); +}