load.hh

// Copyright (C) 2001, 2002, 2003, 2004, 2005, 2006, 2007, 2008, 2009 EPITA Research and Development Laboratory (LRDE)
//
// This file is part of Olena.
//
// Olena is free software: you can redistribute it and/or modify it under
// the terms of the GNU General Public License as published by the Free
// Software Foundation, version 2 of the License.
//
// Olena 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 Olena.  If not, see <http://www.gnu.org/licenses/>.
//
// As a special exception, you may use this file as part of a free
// software project 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_IO_PNM_LOAD_HH
# define MLN_IO_PNM_LOAD_HH


# include <iostream>
# include <fstream>
# include <string>

# include <mln/core/image/image2d.hh>

# include <mln/value/int_u8.hh>
# include <mln/value/rgb.hh>

# include <mln/io/pnm/load_header.hh>
# include <mln/io/pnm/max_component.hh>
# include <mln/io/pnm/macros.hh>

# include <mln/metal/is_a.hh>

namespace mln
{

  namespace io
  {

    namespace pnm
    {


# ifndef MLN_INCLUDE_ONLY

      template <typename I>
      void load_ascii_value(std::ifstream& file, I& ima);

      template <typename I>
      void load_ascii_builtin(std::ifstream& file, I& ima);


      namespace internal
      {

        template <typename I>
        inline
        void
        load_ascii_dispatch(std::ifstream& file, I& ima, const metal::bool_<true>&)
        {
          load_ascii_value(file, ima);
        }

        template <typename I>
        inline
        void
        load_ascii_dispatch(std::ifstream& file, I& ima, const metal::bool_<false>&)
        {
          load_ascii_builtin(file, ima);
        }

      } // end of namespace mln::io::pnm::internal


      // Read a Milena rgb value (sizeof(int_u8) != 1).
      template <unsigned int n>
      inline
      void read_value(std::ifstream& file, value::rgb<n>& v)
      {
        typedef typename value::int_u<n>::enc E;

        E c;
        file.read((char*)(&c), sizeof(E));
        v.red() = c;
        file.read((char*)(&c), sizeof(E));
        v.green() = c;
        file.read((char*)(&c), sizeof(E));
        v.blue() = c;
      }

      // Read a Milena scalar value (sizeof(int_u8) != 1).
      template <class V>
      inline
      void read_value(std::ifstream& file, value::Scalar<V>& v)
      {
        typedef typename V::enc E;

        E c;
        file.read((char*)(&c), sizeof(E));
        exact(v) = c;
      }

      // Read a builtin scalar value.
      template <typename V>
      inline
      void read_value(std::ifstream& file, V& v)
      {
        V c;
        file.read((char*)(&c), sizeof(V));
        v = c;
      }

      // used when (sizeof(int_u8) != 1)
      template <typename V>
      inline
      void load_raw_2d_uncontiguous(std::ifstream& file, image2d<V>& ima)
      {
        const def::coord
          min_row = geom::min_row(ima),
          max_row = geom::max_row(ima),
          min_col = geom::min_col(ima),
          max_col = geom::max_col(ima);

        point2d p;
        for (p.row() = min_row; p.row() <= max_row; ++p.row())
          for (p.col() = min_col; p.col() <= max_col; ++p.col())
            read_value(file, ima(p));
      }

      // used in g++ > 2.95
      template <typename I>
      inline
      void load_raw_2d_contiguous(std::ifstream& file, I& ima)
      {
        point2d p = point2d(0, ima.domain().pmin().col());
        typedef mln_value(I) V;
        const mln_deduce(I, site, coord)
          min_row = geom::min_row(ima),
          max_row = geom::max_row(ima);

        std::size_t len = geom::ncols(ima) * sizeof(V);
        for (p.row() = min_row; p.row() <= max_row; ++p.row())
          file.read((char*)(&ima(p)), len);
      }

      template <typename I>
      inline
      void load_ascii_value(std::ifstream& file, I& ima)
      {
        mln_equiv(mln_value_(I)) c;
        mln_fwd_piter(I) p(ima.domain());
        for_all(p)
        {
          file >> c;
          ima(p) = c;
        }
      }

      template <typename I>
      inline
      void load_ascii_builtin(std::ifstream& file, I& ima)
      {
        mln_fwd_piter(I) p(ima.domain());

        // FIXME: May be wrong!
        // Worked out with an image with a max value of 255
        // loaded in an image2d<unsigned char>.
        unsigned n;

        for_all(p)
        {
          file >> n;
          ima(p) = n;
        }
      }

      template <typename I>
      inline
      void load_raw_2d(std::ifstream& file, I& ima)
      {
        if (sizeof(value::int_u8) == 1)
          load_raw_2d_contiguous(file, ima);
        else
          load_raw_2d_uncontiguous(file, ima);
      }

      template <typename V>
      inline
      image2d<V> load(char type_, const std::string& filename)
      {
        trace::entering("mln::io::pnm::load");

        std::ifstream file(filename.c_str());
        if (! file)
        {
          std::cerr << "error: file '" << filename
                    << "' not found!";
          abort();
        }
        char type = 0;
        int nrows, ncols;
        unsigned int maxval;
        read_header(static_cast<char>(type_ - 3), type_, file, type,
                    nrows, ncols, maxval);

        if (max_component(V()) != maxval)
        {
          std::cerr << "error: file '" << filename
                    << "' cannot be loaded into this type of image"
                    << std::endl;

          std::cerr << "input image have " << maxval
                    << " as maximum value while the destination's one is "
                    << max_component(V()) << " (should be the same)."
                    << std::endl;
          abort();
        }

        image2d<V> ima(nrows, ncols);
        if (type == type_)
          load_raw_2d(file, ima);
        else
          if (type == (type_ - 3))
            pnm::internal::load_ascii_dispatch(file, ima, mlc_is_a(V, mln::Value)());

        trace::exiting("mln::io::pnm::load");

        return ima;
      }

      template <typename I>
      inline
      void load(char type_,
                Image<I>& ima_,
                const std::string& filename)
      {
        trace::entering("mln::io::pnm::load");

        std::ifstream file(filename.c_str());
        if (! file)
        {
          std::cerr << "error: file '" << filename
                    << "' not found!";
          abort();
        }

        I& ima = exact(ima_);

        char type = 0;
        int nrows, ncols;
        unsigned int maxval;
        read_header(static_cast<char>(type_ - 3), type_, file, type,
                    nrows, ncols, maxval);

        if (max_component(mln_value(I)()) != maxval)
        {
          std::cerr << "error: file '" << filename
                    << "' cannot be loaded into this type of image"
                    << std::endl;

          std::cerr << "input image have " << maxval
                    << " as maximum value while the destination's one is "
                    << max_component(mln_value(I)()) << "."
                    << std::endl;
          abort();
        }

        ima.init_(make::box2d(nrows, ncols));
        if (type == type_)
          load_raw_2d(file, ima);
        else
          if (type == (type_ - 3))
            pnm::internal::load_ascii_dispatch(file, ima, mlc_is_a(mln_value(I), mln::Value)());

        trace::exiting("mln::io::pnm::load");
      }

# endif // ! MLN_INCLUDE_ONLY

    } // end of namespace mln::io::pnm

  } // end of namespace mln::io

} // end of namespace mln


#endif // ! MLN_IO_PNM_LOAD_HH