view libinterp/dldfcn/__magick_read__.cc @ 16988:54b75bed4bc7

imwrite: implement WriteMode option. * imwrite.m: document the new option WriteMode and possibility to write multipage images by passing a 4 dimensional matrix. * private/core_imwrite.m: perform input check for the quality option and the new writemode. Set defaults here and not on __magick_write__(). Give warning about the fact that writing of indexed images is not properly implemented. Change calling to ind2rgb() since it has been there and we no longer need workaround. Remove the different calls to __magick_read__() since we now have a single way to do it. Remove conversion of image types since we want to save what was actually given to us. * __magick_read__.cc (read_file): split from __magick_read__() into a separate function so it can be used by __magick_write__() when appending images to an existing file. (jpg_settings): remove function. It only checks for the quality option, which is now done by core_imwrite(). Plus, other formats support this option so it was moved into __magick_write__(). We should have functions for each option rather than per file format. (encode_map): comment whole function since it is never used and is unfinished work to implement writing of actual indexed images. (write_file): new function from part of previous write_image(). It is now the other side of read_file(). (write_image): remove function. Moved into __magick_write__(), the only function calling it. The part of writing moved into write_file(). (__magick_write__): removed most of input check which should be done by imwrite(). Removed all extra usage types. Options must be passed on a non-optional struct. Implement the Append option.
author Carnë Draug <carandraug@octave.org>
date Tue, 16 Jul 2013 17:29:45 +0100
parents 997efb8d0b19
children 7a69ab84b8c9
line wrap: on
line source

/*

Copyright (C) 2013 Carnë Draug
Copyright (C) 2002-2012 Andy Adler
Copyright (C) 2008 Thomas L. Scofield
Copyright (C) 2010 David Grundberg

This file is part of Octave.

Octave 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; either version 3 of the License, or (at your
option) any later version.

Octave 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 Octave; see the file COPYING.  If not, see
<http://www.gnu.org/licenses/>.

*/

#ifdef HAVE_CONFIG_H
#include <config.h>
#endif

#include <cmath>

#include "file-stat.h"
#include "oct-env.h"
#include "oct-time.h"

#include "defun-dld.h"
#include "error.h"
#include "ov-struct.h"

#include "gripes.h"

#ifdef HAVE_MAGICK

#include <Magick++.h>
#include <clocale>

octave_value_list
read_indexed_images (std::vector<Magick::Image>& imvec,
                     const Array<int>& frameidx, bool wantalpha)
{
  octave_value_list output;

  const int rows    = imvec[0].baseRows ();
  const int columns = imvec[0].baseColumns ();
  const int nframes = frameidx.length ();

  const dim_vector idim = dim_vector (rows, columns, 1, nframes);

  Array<int> idx (dim_vector (4, 1));

  Magick::ImageType type = imvec[0].type ();

  unsigned int mapsize = imvec[0].colorMapSize ();
  unsigned int i = mapsize;
  unsigned int depth = 0;
  while (i >>= 1)
    depth++;
  i = 0;
  depth--;
  while (depth >>= 1)
    i++;
  depth = 1 << i;

  switch (depth)
    {
    case 1:
    case 2:
    case 4:
    case 8:
      {
        uint8NDArray im = uint8NDArray (idim);

        idx(2) = 0;
        for (int frame = 0; frame < nframes; frame++)
          {
            imvec[frameidx(frame)].getConstPixels (0, 0, columns, rows);

            const Magick::IndexPacket *pix
              = imvec[frameidx(frame)].getConstIndexes ();

            i = 0;
            idx(3) = frame;

            for (int y = 0; y < rows; y++)
              {
                idx(0) = y;
                for (int x = 0; x < columns; x++)
                  {
                    idx(1) = x;
                    im(idx) = static_cast<octave_uint8> (pix[i++]);
                  }
              }
          }

        output(0) = octave_value (im);
      }
      break;

    case 16:
      {
        uint16NDArray im = uint16NDArray (idim);

        idx(2) = 0;
        for (int frame = 0; frame < nframes; frame++)
          {
            imvec[frameidx(frame)].getConstPixels (0, 0, columns, rows);

            const Magick::IndexPacket *pix
              = imvec[frameidx(frame)].getConstIndexes ();

            i = 0;
            idx(3) = frame;

            for (int y = 0; y < rows; y++)
              {
                idx(0) = y;
                for (int x = 0; x < columns; x++)
                  {
                    idx(1) = x;
                    im(idx) = static_cast<octave_uint16> (pix[i++]);
                  }
              }
          }

        output(0) = octave_value (im);
      }
      break;

    default:
      error ("__magic_read__: index depths greater than 16-bit are not supported");
      return octave_value_list ();
    }

  Matrix map = Matrix (mapsize, 3);
  Matrix alpha;

  switch (type)
    {
    case Magick::PaletteMatteType:
//      warning ("palettematte");
//      Matrix map (mapsize, 3);
//      Matrix alpha (mapsize, 1);
//      for (i = 0; i < mapsize; i++)
//        {
//          warning ("%d", i);
//          Magick::ColorRGB c = imvec[0].colorMap (i);
//          map(i,0) = c.red ();
//          map(i,1) = c.green ();
//          map(i,2) = c.blue ();
//          alpha(i,1) = c.alpha ();
//        }
//      break;

    case Magick::PaletteType:
      alpha = Matrix (0, 0);
      for (i = 0; i < mapsize; i++)
        {
          Magick::ColorRGB c = imvec[0].colorMap (i);
          map(i,0) = c.red ();
          map(i,1) = c.green ();
          map(i,2) = c.blue ();
        }
      break;

    default:
      error ("__magick_read__: unsupported indexed image type");
      return octave_value_list ();
    }

  if (wantalpha)
    output(2) = alpha;

  output(1) = map;

  return output;
}

template <class T>
octave_value_list
read_images (const std::vector<Magick::Image>& imvec,
             const Array<int>& frameidx, unsigned int depth)
{
  typedef typename T::element_type P;

  octave_value_list retval (3, Matrix ());

  T im;

  const int rows    = imvec[0].baseRows ();
  const int columns = imvec[0].baseColumns ();
  const int nframes = frameidx.length ();

  dim_vector idim = dim_vector (rows, columns, 1, nframes);

  Magick::ImageType type = imvec[0].type ();
  const int divisor = ((uint64_t (1) << QuantumDepth) - 1) / 
                      ((uint64_t (1) << depth) - 1);

  switch (type)
    {
    case Magick::BilevelType:           // Monochrome bi-level image
    case Magick::GrayscaleType:         // Grayscale image
      {
        im = T (idim);
        P *vec = im.fortran_vec ();

        for (int frame = 0; frame < nframes; frame++)
          {
            const Magick::PixelPacket *pix
              = imvec[frameidx(frame)].getConstPixels (0, 0, columns, rows);

            P *rbuf = vec;
            for (int y = 0; y < rows; y++)
              {
                for (int x = 0; x < columns; x++)
                  {
                    *rbuf = pix->red / divisor;
                    pix++;
                    rbuf += rows;
                  }
                rbuf -= rows * columns - 1;
              }

            // Next frame.
            vec += rows * columns * idim(2);
          }
        }
      break;

    case Magick::GrayscaleMatteType:    // Grayscale image with opacity
      {
        idim(2) = 2;
        im = T (idim);
        P *vec = im.fortran_vec ();

        for (int frame = 0; frame < nframes; frame++)
          {
            const Magick::PixelPacket *pix
              = imvec[frameidx(frame)].getConstPixels (0, 0, columns, rows);

            P *rbuf = vec;
            P *obuf = vec + rows * columns;
            for (int y = 0; y < rows; y++)
              {
                for (int x = 0; x < columns; x++)
                  {
                    *rbuf = pix->red / divisor;
                    *obuf = pix->opacity / divisor;
                    pix++;
                    rbuf += rows;
                    obuf += rows;
                  }
                rbuf -= rows * columns - 1;
                obuf -= rows * columns - 1;
              }

            // Next frame.
            vec += rows * columns * idim(2);
          }
        }
      break;

    case Magick::PaletteType:           // Indexed color (palette) image
    case Magick::TrueColorType:         // Truecolor image
      {
        idim(2) = 3;
        im = T (idim);
        P *vec = im.fortran_vec ();

        for (int frame = 0; frame < nframes; frame++)
          {
            const Magick::PixelPacket *pix
              = imvec[frameidx(frame)].getConstPixels (0, 0, columns, rows);

            P *rbuf = vec;
            P *gbuf = vec + rows * columns;
            P *bbuf = vec + rows * columns * 2;
            for (int y = 0; y < rows; y++)
              {
                for (int x = 0; x < columns; x++)
                  {
                    *rbuf = pix->red / divisor;
                    *gbuf = pix->green / divisor;
                    *bbuf = pix->blue / divisor;
                    pix++;
                    rbuf += rows;
                    gbuf += rows;
                    bbuf += rows;
                  }
                rbuf -= rows * columns - 1;
                gbuf -= rows * columns - 1;
                bbuf -= rows * columns - 1;
              }

            // Next frame.
            vec += rows * columns * idim(2);
          }
        }
      break;

    case Magick::PaletteMatteType:      // Indexed color (palette) image with opacity
    case Magick::TrueColorMatteType:    // Truecolor image with opacity
    case Magick::ColorSeparationType:   // Cyan/Yellow/Magenta/Black (CYMK) image
      {
        idim(2) = 4;
        im = T (idim);
        P *vec = im.fortran_vec ();

        for (int frame = 0; frame < nframes; frame++)
          {
            const Magick::PixelPacket *pix
              = imvec[frameidx(frame)].getConstPixels (0, 0, columns, rows);

            P *rbuf = vec;
            P *gbuf = vec + rows * columns;
            P *bbuf = vec + rows * columns * 2;
            P *obuf = vec + rows * columns * 3;
            for (int y = 0; y < rows; y++)
              {
                for (int x = 0; x < columns; x++)
                  {
                    *rbuf = pix->red / divisor;
                    *gbuf = pix->green / divisor;
                    *bbuf = pix->blue / divisor;
                    *obuf = pix->opacity / divisor;
                    pix++;
                    rbuf += rows;
                    gbuf += rows;
                    bbuf += rows;
                    obuf += rows;
                  }
                rbuf -= rows * columns - 1;
                gbuf -= rows * columns - 1;
                bbuf -= rows * columns - 1;
                obuf -= rows * columns - 1;
              }

            // Next frame.
            vec += rows * columns * idim(2);
          }
        }
      break;

    default:
      error ("__magick_read__: undefined Magick++ image type");
      return retval;
    }

  retval(0) = im;

  return retval;
}

void static
read_file (const std::string filename, std::vector<Magick::Image>& imvec)
{
  try
    {
      // Read a file into vector of image objects
      Magick::readImages (&imvec, filename);
    }
  catch (Magick::Warning& w)
    {
      warning ("Magick++ warning: %s", w.what ());
    }
  catch (Magick::ErrorCoder& e)
    {
      // FIXME: there's a WarningCoder and ErrorCoder. Shouldn't this
      // exception cause an error?
      warning ("Magick++ coder error: %s", e.what ());
    }
  catch (Magick::Exception& e)
    {
      error ("Magick++ exception: %s", e.what ());
      error_state = 1;
    }
}


static void
maybe_initialize_magick (void)
{
  static bool initialized = false;

  if (! initialized)
    {
      // Save locale as GraphicsMagick might change this (fixed in
      // GraphicsMagick since version 1.3.13 released on December 24, 2011)
      const char *static_locale = setlocale (LC_ALL, NULL);
      const std::string locale (static_locale);

      const std::string program_name = octave_env::get_program_invocation_name ();

      Magick::InitializeMagick (program_name.c_str ());

      // Restore locale from before GraphicsMagick initialisation
      setlocale (LC_ALL, locale.c_str ());

      if (QuantumDepth < 32)
        warning ("your version of %s limits images to %d bits per pixel",
                 MagickPackageName, QuantumDepth);

      initialized = true;
    }
}
#endif

DEFUN_DLD (__magick_read__, args, nargout,
  "-*- texinfo -*-\n\
@deftypefn {Loadable Function} {[@var{img}, @var{map}, @var{alpha}] =} __magick_read__ (@var{fname}, @var{options})\n\
Read image with GraphicsMagick or ImageMagick.\n\
\n\
This is a private internal function not intended for direct use.  Instead\n\
use @code{imread}.\n\
\n\
@seealso{imfinfo, imformats, imread, imwrite}\n\
@end deftypefn")
{
  octave_value_list output;

#ifndef HAVE_MAGICK
  gripe_disabled_feature ("imread", "Image IO");
#else

  maybe_initialize_magick ();

  if (args.length () != 2 || ! args(0).is_string ())
    {
      print_usage ();
      return output;
    }

  const octave_map options = args(1).map_value ();
  if (error_state)
    {
      error ("__magick_read__: OPTIONS must be a struct");
    }

  std::vector<Magick::Image> imvec;
  read_file (args(0).string_value (), imvec);
  if (error_state)
    {
      return output;
    }

  const int nframes = imvec.size ();
  Array<int> frameidx;

  const octave_value indexes = options.getfield ("index")(0);
  if (indexes.is_string () && indexes.string_value () == "all")
    {
      frameidx = Array<int> (dim_vector (1, nframes));
      for (int i = 0; i < nframes; i++)
        {
          frameidx(i) = i;
        }
    }
  else
    {
      frameidx = indexes.int_vector_value ();
      if (error_state)
        {
          error ("__magick_read__: invalid value for Index/Frame");
        }
      // Fix indexex from base 1 to base 0, and at the same time, make
      // sure none of the indexes is outside the range of image number.
      const int n = frameidx.nelem ();
      for (int i = 0; i < n; i++)
        {
          frameidx(i)--;
          if (frameidx(i) < 0 || frameidx(i) > nframes - 1)
            {
              error ("imread: index/frames specified are outside the number of images");
              return output;
            }
        }
    }

  const Magick::ClassType klass = imvec[0].classType ();

  // PseudoClass:
  // Image is composed of pixels which specify an index in a color palette.
  if (klass == Magick::PseudoClass && nargout > 1)
    {
      output = read_indexed_images (imvec, frameidx, (nargout == 3));
    }
  // If not PseudoClass then it must be DirectClass: Image is composed of
  // pixels which represent literal color values.
  else
    {
      unsigned int depth = imvec[0].modulusDepth ();
      if (depth > 1)
        {
          --depth;
          int i = 1;
          while (depth >>= 1)
            i++;
          depth = 1 << i;
        }

      switch (depth)
        {
        case 1:
          output = read_images<boolNDArray> (imvec, frameidx, depth);
          break;

        case 2:
        case 4:
        case 8:
          output = read_images<uint8NDArray> (imvec, frameidx, depth) ;
          break;

        case 16:
          output = read_images<uint16NDArray> (imvec, frameidx, depth);
          break;

        case 32:
        case 64:
        default:
          error ("__magick_read__: image depths greater than 16-bit are not supported");
        }
    }

#endif
  return output;
}

/*
## No test needed for internal helper function.
%!assert (1)
*/

#ifdef HAVE_MAGICK

static void
encode_bool_image (std::vector<Magick::Image>& imvec, const octave_value& img)
{
  unsigned int nframes = 1;
  boolNDArray m = img.bool_array_value ();

  dim_vector dsizes = m.dims ();
  if (dsizes.length () == 4)
    nframes = dsizes(3);

  Array<octave_idx_type> idx (dim_vector (dsizes.length (), 1));

  octave_idx_type rows = m.rows ();
  octave_idx_type columns = m.columns ();

  for (unsigned int ii = 0; ii < nframes; ii++)
    {
      Magick::Image im (Magick::Geometry (columns, rows), "black");
      im.classType (Magick::DirectClass);
      im.depth (1);

      for (int y = 0; y < columns; y++)
        {
          idx(1) = y;

          for (int x = 0; x < rows; x++)
            {
              if (nframes > 1)
                {
                  idx(2) = 0;
                  idx(3) = ii;
                }

              idx(0) = x;

              if (m(idx))
                im.pixelColor (y, x, "white");
            }
        }

      im.quantizeColorSpace (Magick::GRAYColorspace);
      im.quantizeColors (2);
      im.quantize ();

      imvec.push_back (im);
    }
}

template <class T>
static void
encode_uint_image (std::vector<Magick::Image>& imvec,
                   const octave_value& img,
                   const bool has_map)
{
  unsigned int bitdepth = 0;
  T m;

  if (img.is_uint8_type ())
    {
      bitdepth = 8;
      m = img.uint8_array_value ();
    }
  else if (img.is_uint16_type ())
    {
      bitdepth = 16;
      m = img.uint16_array_value ();
    }
  else
    error ("__magick_write__: invalid image class");

  const dim_vector dsizes = m.dims ();
  unsigned int nframes = 1;
  if (dsizes.length () == 4)
    nframes = dsizes(3);

  const bool is_color = ((dsizes.length () > 2) && (dsizes(2) > 2));
  const bool has_alpha = (dsizes.length () > 2 && (dsizes(2) == 2 || dsizes(2) == 4));

  Array<octave_idx_type> idx (dim_vector (dsizes.length (), 1));
  octave_idx_type rows = m.rows ();
  octave_idx_type columns = m.columns ();

  unsigned int div_factor = (1 << bitdepth) - 1;

  for (unsigned int ii = 0; ii < nframes; ii++)
    {
      Magick::Image im (Magick::Geometry (columns, rows), "black");

      im.depth (bitdepth);

      if (has_map)
        im.classType (Magick::PseudoClass);
      else
        im.classType (Magick::DirectClass);

      if (is_color)
        {
          if (has_alpha)
            im.type (Magick::TrueColorMatteType);
          else
            im.type (Magick::TrueColorType);

          Magick::ColorRGB c;

          for (int y = 0; y < columns; y++)
            {
              idx(1) = y;

              for (int x = 0; x < rows; x++)
                {
                  idx(0) = x;

                  if (nframes > 1)
                    idx(3) = ii;

                  idx(2) = 0;
                  c.red (static_cast<double>(m(idx)) / div_factor);

                  idx(2) = 1;
                  c.green (static_cast<double>(m(idx)) / div_factor);

                  idx(2) = 2;
                  c.blue (static_cast<double>(m(idx)) / div_factor);

                  if (has_alpha)
                    {
                      idx(2) = 3;
                      c.alpha (static_cast<double>(m(idx)) / div_factor);
                    }

                  im.pixelColor (y, x, c);
                }
            }
        }
      else
        {
          if (has_alpha)
            im.type (Magick::GrayscaleMatteType);
          else
            im.type (Magick::GrayscaleType);

          Magick::ColorGray c;

          for (int y = 0; y < columns; y++)
            {
              idx(1) = y;

              for (int x=0; x < rows; x++)
                {
                  idx(0) = x;

                  if (nframes > 1)
                    {
                      idx(2) = 0;
                      idx(3) = ii;
                    }

                  if (has_alpha)
                    {
                      idx(2) = 1;
                      c.alpha (static_cast<double>(m(idx)) / div_factor);
                      idx(2) = 0;
                    }

                  c.shade (static_cast<double>(m(idx)) / div_factor);

                  im.pixelColor (y, x, c);
                }
            }

          im.quantizeColorSpace (Magick::GRAYColorspace);
          im.quantizeColors (1 << bitdepth);
          im.quantize ();
        }

      imvec.push_back (im);
    }
}

// FIXME: this will be needed to write indexed images
//static void
//encode_map (std::vector<Magick::Image>& imvec, const NDArray& cmap)
//{
//  unsigned int mapsize = cmap.dim1 ();

//  for (size_t fnum = 0; fnum < imvec.size (); fnum++)
//    {
//      imvec[fnum].colorMapSize (mapsize);
//      imvec[fnum].type (Magick::PaletteType);
//    }

//  for (unsigned int ii = 0; ii < mapsize; ii++)
//    {
//      Magick::ColorRGB c (cmap(ii,0), cmap(ii,1), cmap(ii,2));

//      // FIXME -- is this case needed?
//      if (cmap.dim2 () == 4)
//        c.alpha (cmap(ii,3));

//      try
//        {
//          for_each (imvec.begin (), imvec.end (),
//                    Magick::colorMapImage (ii, c));
//        }
//      catch (Magick::Warning& w)
//        {
//          warning ("Magick++ warning: %s", w.what ());
//        }
//      catch (Magick::ErrorCoder& e)
//        {
//          warning ("Magick++ coder error: %s", e.what ());
//        }
//      catch (Magick::Exception& e)
//        {
//          error ("Magick++ exception: %s", e.what ());
//        }
//    }
//}

void static
write_file (const std::string filename,
            const std::string ext,
            std::vector<Magick::Image>& imvec)
{
  try
    {
      Magick::writeImages (imvec.begin (), imvec.end (), ext + ":" + filename);
    }
  catch (Magick::Warning& w)
    {
      warning ("Magick++ warning: %s", w.what ());
    }
  catch (Magick::ErrorCoder& e)
    {
      warning ("Magick++ coder error: %s", e.what ());
    }
  catch (Magick::Exception& e)
    {
      error ("Magick++ exception: %s", e.what ());
      error_state = 1;
    }
}

#endif

DEFUN_DLD (__magick_write__, args, ,
  "-*- texinfo -*-\n\
@deftypefn {Loadable Function} {} __magick_write__ (@var{fname}, @var{fmt}, @var{img}, @var{map}, @var{options})\n\
Write image with GraphicsMagick or ImageMagick.\n\
\n\
This is a private internal function not intended for direct use.  Instead\n\
use @code{imwrite}.\n\
\n\
@seealso{imfinfo, imformats, imread, imwrite}\n\
@end deftypefn")
{
  octave_value_list retval;

#ifndef HAVE_MAGICK
  gripe_disabled_feature ("imwrite", "Image IO");
#else

  maybe_initialize_magick ();

  if (args.length () != 5 || ! args(0).is_string () || ! args(1).is_string ())
    {
      print_usage ();
      return retval;
    }
  const std::string filename = args(0).string_value ();
  const std::string ext      = args(1).string_value ();

  const octave_map options   = args(4).map_value ();
  if (error_state)
    {
      error ("__magick_write__: OPTIONS must be a struct");
    }

  const octave_value img  = args(2);
  const Matrix       cmap = args(3).matrix_value ();
  if (error_state)
    {
      error ("__magick_write__: invalid IMG or MAP");
    }
  const bool is_indexed = ! cmap.is_empty ();

  // Create vector with the images to write
  std::vector<Magick::Image> imvec;
  if (img.is_bool_type ())
    {
      encode_bool_image (imvec, img);
    }
  else if (img.is_uint8_type ())
    {
      encode_uint_image<uint8NDArray> (imvec, img, is_indexed);
    }
  else if (img.is_uint16_type ())
    {
      encode_uint_image<uint16NDArray> (imvec, img, is_indexed);
    }
  else
    {
      error ("__magick_write__: image type not supported");
      return retval;
    }
  const int nframes = imvec.size ();

  // Add colormap to image
  if (is_indexed)
    {
    // FIXME: this should be implemented. At the moment, imwrite is doing the
    //        conversion in case of indexed images.
      error ("__magick_write__: direct saving of indexed images not currently supported; use ind2rgb and save converted image");
//      encode_map (imvec, cmap);
      return retval;
    }

  // Set quality.
  // FIXME What happens when we try to set with formats that do not support it?
  const unsigned int quality = options.getfield ("quality")(0).int_value ();
  for (int i = 0; i < nframes; i++)
    {
      imvec[i].quality (quality);
    }

  // Finally, save the file.
  // If writemode is set to append, read the image first, append to it,
  // and then save it. But even if set to append, make sure anything was
  // read at all.
  const std::string writemode = options.getfield ("writemode")(0).string_value ();
  std::vector<Magick::Image> ini_imvec;
  if (writemode == "append")
    {
      read_file (filename, ini_imvec);
      if (error_state)
        {
          return retval;
        }
    }

  if (ini_imvec.size () > 0)
    {
      ini_imvec.insert (ini_imvec.end (), imvec.begin (), imvec.end ());
      write_file (filename, ext, ini_imvec);
      if (error_state)
        {
          return retval;
        }
    }
  else
    {
      write_file (filename, ext, imvec);
      if (error_state)
        {
          return retval;
        }
    }

#endif
  return retval;
}

/*
## No test needed for internal helper function.
%!assert (1)
*/

#ifdef HAVE_MAGICK

template<class T>
static octave_value
magick_to_octave_value (const T magick)
{
  return octave_value (magick);
}

static octave_value
magick_to_octave_value (const Magick::EndianType magick)
{
  switch (magick)
    {
      case Magick::LSBEndian:
        return octave_value ("little-endian");

      case Magick::MSBEndian:
        return octave_value ("big-endian");

      default:
        return octave_value ("undefined");
    }
}

static octave_value
magick_to_octave_value (const Magick::ResolutionType magick)
{
  switch (magick)
    {
      case Magick::PixelsPerInchResolution:
        return octave_value ("pixels per inch");

      case Magick::PixelsPerCentimeterResolution:
        return octave_value ("pixels per centimeter");

      default:
        return octave_value ("undefined");
    }
}

static octave_value
magick_to_octave_value (const Magick::ImageType magick)
{
  switch (magick)
    {
      case Magick::BilevelType:
      case Magick::GrayscaleType:
      case Magick::GrayscaleMatteType:
        return octave_value ("grayscale");

      case Magick::PaletteType:
      case Magick::PaletteMatteType:
        return octave_value ("indexed");

      case Magick::TrueColorType:
      case Magick::TrueColorMatteType:
      case Magick::ColorSeparationType:
        return octave_value ("truecolor");

      default:
        return octave_value ("undefined");
    }
}

// We put this in a try-block because GraphicsMagick will throw
// exceptions if a parameter isn't present in the current image.
#define GET_PARAM(NAME, OUTNAME) \
  try \
    { \
      info.contents (OUTNAME)(frame,0) = magick_to_octave_value (im.NAME ()); \
    } \
  catch (Magick::Warning& w) \
    { \
    }

#endif

DEFUN_DLD (__magick_finfo__, args, ,
  "-*- texinfo -*-\n\
@deftypefn {Loadable Function} {} __magick_finfo__ (@var{fname})\n\
Read image information with GraphicsMagick or ImageMagick.\n\
\n\
This is a private internal function not intended for direct use.  Instead\n\
use @code{imfinfo}.\n\
\n\
@seealso{imfinfo, imformats, imread, imwrite}\n\
@end deftypefn")
{
  octave_value retval;

#ifndef HAVE_MAGICK
  gripe_disabled_feature ("imfinfo", "Image IO");
#else

  maybe_initialize_magick ();

  if (args.length () < 1 || ! args (0).is_string ())
    {
      print_usage ();
      return retval;
    }

  const std::string filename = args (0).string_value ();

  try
    {
      // Read the file.
      std::vector<Magick::Image> imvec;
      Magick::readImages (&imvec, args(0).string_value ());
      int nframes = imvec.size ();

      // Create the right size for the output.

      static const char *fields[] =
        {
          "Filename",
          "FileModDate",
          "FileSize",
          "Height",
          "Width",
          "BitDepth",
          "Format",
          "LongFormat",
          "XResolution",
          "YResolution",
          "TotalColors",
          "TileName",
          "AnimationDelay",
          "AnimationIterations",
          "ByteOrder",
          "Gamma",
          "Matte",
          "ModulusDepth",
          "Quality",
          "QuantizeColors",
          "ResolutionUnits",
          "ColorType",
          "View",
          0
        };

      octave_map info (dim_vector (nframes, 1), string_vector (fields));

      file_stat fs (filename);

      std::string filetime;

      if (fs)
        {
          octave_localtime mtime = fs.mtime ();

          filetime = mtime.strftime ("%e-%b-%Y %H:%M:%S");
        }
      else
        {
          std::string msg = fs.error ();

          error ("imfinfo: error reading '%s': %s",
                 filename.c_str (), msg.c_str ());

          return retval;
        }

      // For each frame in the image (some images contain multiple
      // layers, each to be treated like a separate image).
      for (int frame = 0; frame < nframes; frame++)
        {
          Magick::Image im = imvec[frame];

          // Add file name and timestamp.
          info.contents ("Filename")(frame,0) = filename;
          info.contents ("FileModDate")(frame,0) = filetime;

          // Annoying CamelCase naming is for Matlab compatibility.
          GET_PARAM (fileSize, "FileSize")
          GET_PARAM (rows, "Height")
          GET_PARAM (columns, "Width")
          GET_PARAM (depth, "BitDepth")
          GET_PARAM (magick, "Format")
          GET_PARAM (format, "LongFormat")
          GET_PARAM (xResolution, "XResolution")
          GET_PARAM (yResolution, "YResolution")
          GET_PARAM (totalColors, "TotalColors")
          GET_PARAM (tileName, "TileName")
          GET_PARAM (animationDelay, "AnimationDelay")
          GET_PARAM (animationIterations, "AnimationIterations")
          GET_PARAM (endian, "ByteOrder")
          GET_PARAM (gamma, "Gamma")
          GET_PARAM (matte, "Matte")
          GET_PARAM (modulusDepth, "ModulusDepth")
          GET_PARAM (quality, "Quality")
          GET_PARAM (quantizeColors, "QuantizeColors")
          GET_PARAM (resolutionUnits, "ResolutionUnits")
          GET_PARAM (type, "ColorType")
          GET_PARAM (view, "View")
        }

      retval = octave_value (info);
    }
  catch (Magick::Warning& w)
    {
      warning ("Magick++ warning: %s", w.what ());
    }
  catch (Magick::ErrorCoder& e)
    {
      warning ("Magick++ coder error: %s", e.what ());
    }
  catch (Magick::Exception& e)
    {
      error ("Magick++ exception: %s", e.what ());
      return retval;
    }
#endif
  return retval;
}

/*
## No test needed for internal helper function.
%!assert (1)
*/

#undef GET_PARAM

DEFUN_DLD (__magick_formats__, args, ,
  "-*- texinfo -*-\n\
@deftypefn {Loadable Function} {} __magick_imformats__ (@var{formats})\n\
Fill formats info with GraphicsMagick CoderInfo.\n\
\n\
@seealso{imfinfo, imformats, imread, imwrite}\n\
@end deftypefn")
{
  octave_value retval;
#ifndef HAVE_MAGICK
  gripe_disabled_feature ("imformats", "Image IO");
#else
  if (args.length () != 1 || ! args (0).is_map ())
    {
      print_usage ();
      return retval;
    }
  octave_map formats = args(0).map_value ();

  maybe_initialize_magick ();
  for (octave_idx_type idx = 0; idx < formats.numel (); idx++)
    {
      try
        {
          octave_scalar_map fmt = formats.checkelem (idx);
          Magick::CoderInfo coder (fmt.getfield ("coder").string_value ());

          fmt.setfield ("description", octave_value (coder.description ()));
          fmt.setfield ("multipage", coder.isMultiFrame () ? true : false);
          // default for read and write is a function handle. If we can't
          // read or write them, them set it to an empty value
          if (! coder.isReadable ())
            fmt.setfield ("read",  Matrix ());
          if (! coder.isWritable ())
            fmt.setfield ("write", Matrix ());
          formats.fast_elem_insert (idx, fmt);
        }
      catch (Magick::Exception& e)
        {
          // Exception here are missing formats. So we remove the format
          // from the structure and reduce idx.
          formats.delete_elements (idx);
          idx--;
        }
    }
  retval = formats;
#endif
  return retval;
}

/*
## No test needed for internal helper function.
%!assert (1)
*/