From: Jimmy Ma <jimmy.ma@lrde.epita.fr> To: olena-patches@lrde.epita.fr Subject: r2737: Add skeleton algorithm URL: https://svn.lrde.epita.fr/svn/oln/branches/cleanup-2008/milena/sandbox ChangeLog: 2008-10-30 Jimmy Ma <jimmy.ma@lrde.epita.fr> Add skeleton algorithm. * garrigues/ocr/skel.cc: New. --- skel.cc | 155 ++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++ 1 file changed, 155 insertions(+) Index: branches/cleanup-2008/milena/sandbox/garrigues/ocr/skel.cc =================================================================== --- branches/cleanup-2008/milena/sandbox/garrigues/ocr/skel.cc (revision 0) +++ branches/cleanup-2008/milena/sandbox/garrigues/ocr/skel.cc (revision 2737) @@ -0,0 +1,155 @@ +# include <mln/core/var.hh> + +# include <mln/core/image/image2d.hh> +# include <mln/core/alias/neighb2d.hh> +# include <mln/core/site_set/p_queue_fast.hh> +# include <mln/core/site_set/p_priority.hh> + +# include <mln/io/pbm/load.hh> +# include <mln/io/pbm/save.hh> +# include <mln/value/int_u8.hh> + +# include <mln/level/fill.hh> + +# include <mln/debug/println.hh> + +# include "simple_point.hh" + + +namespace mln +{ + + template <typename D, typename I, typename N> + mln_ch_value(I, D) + distance(D, const I& input, const N& nbh) + { + const D M = mln_max(D); + mln_ch_value(I, D) output; + initialize(output, input); + + mln_ch_value(I, bool) deja_vu; + initialize(deja_vu, input); + level::fill(deja_vu, input); + + typedef mln_site(I) P; + p_queue_fast<P> q; + + // Initialization. + { + level::fill(output, M); + mln_piter(I) p(input.domain()); + mln_niter(N) n(nbh, p); + for_all(p) + if (input(p) == true) // p in object + { + output(p) = 0; + for_all(n) + if (input.domain().has(n) && input(n) == false) // n in background + { + q.push(p); + break; + } + } + } + + // Propagation. + { + P p; + mln_niter(N) n(nbh, p); + while (! q.is_empty()) + { + p = q.pop_front(); + for_all(n) + if (input.domain().has(n) && output(n) == M) + { + output(n) = output(p) + 1; + if (output(n) == M) + { + // Saturation so stop. + q.clear(); + break; + } + q.push(n); + deja_vu(n) = true; + } + } + } + + return output; + } + + image2d<bool> + skel(const image2d<bool>& input, unsigned nbh_i) + { + neighb2d nbh = int_to_neighb(nbh_i); + image2d<bool> output; + initialize(output, input); + + image2d<value::int_u16> dist_map = distance(value::int_u16(), input, nbh); + + typedef mln_site_(image2d<bool>) P; + p_priority<value::int_u16, p_queue_fast<P> > q; + + // Initialization. + { + level::fill(output, input); + mln_piter_(image2d<bool>) p(output.domain()); + for_all(p) + if (output(p) && + is_simple_point2d(output, nbh_i, p) && // p is a not simple point of object + !is_curve_extremum(output, nbh_i, p)) + { + output(p) = false; // Remove p from object + q.push(dist_map(p), p); + } + } + + // Propagation. + { + P p; + mln_niter_(neighb2d) n(nbh, p); + while (! q.is_empty()) + { + p = q.pop_front(); + + for_all(n) + if (output.domain().has(n) && + output(n) && + is_simple_point2d(output, nbh_i, n) && // n is not simple + !is_curve_extremum(output, nbh_i, n)) + { + output(n) = false; // Remove p from object + q.push(dist_map(n), n); + } + } + } + + return output; + } + +} // mln + + + +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); + + image2d<bool> input; + io::pbm::load(input, argv[1]); + + image2d<bool> output = skel(input, 4); + io::pbm::save(output, argv[2]); +}