/* This file is an image processing operation for GEGL

 *

 * GEGL is free software; you can redistribute it and/or

 * modify it under the terms of the GNU Lesser General Public

 * License as published by the Free Software Foundation; either

 * version 3 of the License, or (at your option) any later version.

 *

 * GEGL 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

 * Lesser General Public License for more details.

 *

 * You should have received a copy of the GNU Lesser General Public

 * License along with GEGL; if not, see <http://www.gnu.org/licenses/>.

 *

 * Copyright 2006 Øyvind Kolås <pippin@gimp.org>

 */

#ifdef GEGL_CHANT_PROPERTIES

   /* no properties */

#else

#define GEGL_CHANT_TYPE_POINT_FILTER

#define GEGL_CHANT_C_FILE       "unpremul.c"

#define GEGLV4

#include "gegl-chant.h"

static gboolean

process (GeglOperation       *op,

         void                *in_buf,

         void                *out_buf,

         glong                samples,

         const GeglRectangle *roi,

         gint                 level)

{

  glong   i;

  gfloat *in  = in_buf;

  gfloat *out = out_buf;

  for (i=0; i

    {

      int  j;

      for (j=0; j<3; j++)

        {

          if (in[3] != 0)

            out[j] = in[j] / in[3];

          else

            out[j] = 0.0;

        }

      out[3]=in[3];

      in += 4;

      out+= 4;

    }

  return TRUE;

}

static void

gegl_chant_class_init (GeglChantClass *klass)

{

  GeglOperationClass            *operation_class;

  GeglOperationPointFilterClass *point_filter_class;

  operation_class    = GEGL_OPERATION_CLASS (klass);

  point_filter_class = GEGL_OPERATION_POINT_FILTER_CLASS (klass);

  point_filter_class->process = process;

  gegl_operation_class_set_keys (operation_class,

    "name"        , "gegl:unpremul",

    "categories"  , "color",

    "description" , "Unpremultiplies a buffer that contains pre-multiplied colors (but is marked as not having it)",

    NULL);

}

#endif