/* hough transform

 *

 * 7/3/14

 *  - from hist_find.c

 */

/*

  This file is part of VIPS.

  VIPS 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 2 of the License, or

  (at your option) any later version.

  This program 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 this program; if not, write to the Free Software

  Foundation, Inc., 51 Franklin Street, Fifth Floor, Boston, MA

  02110-1301  USA

 */

/*

  These files are distributed with VIPS - http://www.vips.ecs.soton.ac.uk

 */

#ifdef HAVE_CONFIG_H

#include <config.h>

#endif /*HAVE_CONFIG_H*/

#include <glib/gi18n-lib.h>

#include <string.h>

#include <vips/vips.h>

#include "statistic.h"

#include "hough.h"

G_DEFINE_ABSTRACT_TYPE(VipsHough, vips_hough, VIPS_TYPE_STATISTIC);

static VipsImage *

vips_hough_new_accumulator(VipsHough *hough)

{

  VipsHoughClass *class = VIPS_HOUGH_GET_CLASS(hough);

  VipsStatistic *statistic = VIPS_STATISTIC(hough);

  VipsImage *accumulator;

  accumulator = vips_image_new_memory();

  if (vips_image_pipelinev(accumulator,

      VIPS_DEMAND_STYLE_ANY, statistic->ready, NULL) ||

    class->init_accumulator(hough, accumulator) ||

    vips_image_write_prepare(accumulator)) {

    g_object_unref(accumulator);

    return NULL;

  }

  return accumulator;

}

static int

vips_hough_build(VipsObject *object)

{

  VipsObjectClass *class = VIPS_OBJECT_GET_CLASS(object);

  VipsStatistic *statistic = VIPS_STATISTIC(object);

  VipsHough *hough = (VipsHough *) object;

  VipsImage *out;

  /* Mono only, we use the bands dimension of the output image for

   * a parameter.

   */

  if (statistic->in)

    if (vips_check_mono(class->nickname, statistic->in))

      return -1;

  if (!(out = vips_hough_new_accumulator(hough)))

    return -1;

  g_object_set(object,

    "out", out,

    NULL);

  if (VIPS_OBJECT_CLASS(vips_hough_parent_class)->build(object))

    return -1;

  return 0;

}

/* Build a new accumulator.

 */

static void *

vips_hough_start(VipsStatistic *statistic)

{

  VipsHough *hough = (VipsHough *) statistic;

  VipsImage *accumulator;

  if (!(accumulator = vips_hough_new_accumulator(hough)))

    return NULL;

  return (void *) accumulator;

}

/* Add our finished accumulator to the main area.

 */

static int

vips_hough_stop(VipsStatistic *statistic, void *seq)

{

  VipsImage *accumulator = (VipsImage *) seq;

  VipsHough *hough = (VipsHough *) statistic;

  if (vips_draw_image(hough->out, accumulator, 0, 0,

      "mode", VIPS_COMBINE_MODE_ADD,

      NULL)) {

    g_object_unref(accumulator);

    return -1;

  }

  g_object_unref(accumulator);

  return 0;

}

static int

vips_hough_scan(VipsStatistic *statistic,

  void *seq, int x, int y, void *in, int n)

{

  VipsHough *hough = (VipsHough *) statistic;

  VipsHoughClass *class = VIPS_HOUGH_GET_CLASS(hough);

  VipsImage *accumulator = (VipsImage *) seq;

  VipsPel *p = (VipsPel *) in;

  int i;

  for (i = 0; i < n; i++)

    if (p[i])

      class->vote(hough, accumulator, x + i, y);

  return 0;

}

#define UC VIPS_FORMAT_UCHAR

/* Input image is cast to this format.

 */

static const VipsBandFormat vips_hough_format_table[10] = {

  /* Band format:  UC  C   US  S   UI  I   F   X   D   DX */

  /* Promotion: */ UC, UC, UC, UC, UC, UC, UC, UC, UC, UC

};

static void

vips_hough_class_init(VipsHoughClass *class)

{

  GObjectClass *gobject_class = (GObjectClass *) class;

  VipsObjectClass *object_class = (VipsObjectClass *) class;

  VipsStatisticClass *sclass = VIPS_STATISTIC_CLASS(class);

  gobject_class->set_property = vips_object_set_property;

  gobject_class->get_property = vips_object_get_property;

  object_class->nickname = "hough";

  object_class->description = _("find hough transform");

  object_class->build = vips_hough_build;

  sclass->start = vips_hough_start;

  sclass->scan = vips_hough_scan;

  sclass->stop = vips_hough_stop;

  sclass->format_table = vips_hough_format_table;

  VIPS_ARG_IMAGE(class, "out", 100,

    _("Output"),

    _("Output image"),

    VIPS_ARGUMENT_REQUIRED_OUTPUT,

    G_STRUCT_OFFSET(VipsHough, out));

}

static void

vips_hough_init(VipsHough *hough)

{

}