gstreamer/gst/median/gstmedian.c

/* GStreamer
 * Copyright (C) <1999> Erik Walthinsen <omega@cse.ogi.edu>
 *
 * This library is free software; you can redistribute it and/or
 * modify it under the terms of the GNU Library General Public
 * License as published by the Free Software Foundation; either
 * version 2 of the License, or (at your option) any later version.
 *
 * This library 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
 * Library General Public License for more details.
 *
 * You should have received a copy of the GNU Library General Public
 * License along with this library; if not, write to the
 * Free Software Foundation, Inc., 59 Temple Place - Suite 330,
 * Boston, MA 02111-1307, USA.
 */

#ifdef HAVE_CONFIG_H
#include "config.h"
#endif
#include <string.h>
#include "gstmedian.h"
#include <gst/video/video.h>

static GstStaticPadTemplate median_src_factory = GST_STATIC_PAD_TEMPLATE ("src",
    GST_PAD_SRC,
    GST_PAD_ALWAYS,
    GST_STATIC_CAPS (GST_VIDEO_CAPS_YUV ("I420"))
    );

static GstStaticPadTemplate median_sink_factory =
GST_STATIC_PAD_TEMPLATE ("sink",
    GST_PAD_SINK,
    GST_PAD_ALWAYS,
    GST_STATIC_CAPS (GST_VIDEO_CAPS_YUV ("I420"))
    );


/* Median signals and args */
enum
{
  /* FILL ME */
  LAST_SIGNAL
};

enum
{
  ARG_0,
  ARG_ACTIVE,
  ARG_FILTERSIZE,
  ARG_LUM_ONLY
};

static GType gst_median_get_type (void);
static void gst_median_class_init (GstMedianClass * klass);
static void gst_median_base_init (GstMedianClass * klass);
static void gst_median_init (GstMedian * median);

static void median_5 (unsigned char *src, unsigned char *dest, int height,
    int width);
static void median_9 (unsigned char *src, unsigned char *dest, int height,
    int width);
static void gst_median_chain (GstPad * pad, GstData * _data);

static void gst_median_set_property (GObject * object, guint prop_id,
    const GValue * value, GParamSpec * pspec);
static void gst_median_get_property (GObject * object, guint prop_id,
    GValue * value, GParamSpec * pspec);

static GstElementClass *parent_class = NULL;

/*static guint gst_median_signals[LAST_SIGNAL] = { 0 }; */

GType
gst_median_get_type (void)
{
  static GType median_type = 0;

  if (!median_type) {
    static const GTypeInfo median_info = {
      sizeof (GstMedianClass),
      (GBaseInitFunc) gst_median_base_init,
      NULL,
      (GClassInitFunc) gst_median_class_init,
      NULL,
      NULL,
      sizeof (GstMedian),
      0,
      (GInstanceInitFunc) gst_median_init,
    };

    median_type =
        g_type_register_static (GST_TYPE_ELEMENT, "GstMedian", &median_info, 0);
  }
  return median_type;
}

static void
gst_median_base_init (GstMedianClass * klass)
{
  GstElementClass *element_class = GST_ELEMENT_CLASS (klass);

  gst_element_class_add_pad_template (element_class,
      gst_static_pad_template_get (&median_sink_factory));
  gst_element_class_add_pad_template (element_class,
      gst_static_pad_template_get (&median_src_factory));
  gst_element_class_set_details_simple (element_class, "Median effect",
      "Filter/Effect/Video",
      "Apply a median filter to an image",
      "Wim Taymans <wim.taymans@chello.be>");
}

static void
gst_median_class_init (GstMedianClass * klass)
{
  GObjectClass *gobject_class;
  GstElementClass *gstelement_class;

  gobject_class = (GObjectClass *) klass;
  gstelement_class = (GstElementClass *) klass;

  parent_class = g_type_class_peek_parent (klass);

  /* FIXME: add long property descriptions */
  g_object_class_install_property (G_OBJECT_CLASS (klass), ARG_ACTIVE,
      g_param_spec_boolean ("active", "active", "active", TRUE,
          G_PARAM_READWRITE | G_PARAM_STATIC_STRINGS));
  g_object_class_install_property (G_OBJECT_CLASS (klass), ARG_FILTERSIZE,
      g_param_spec_int ("filtersize", "filtersize", "filtersize", G_MININT,
          G_MAXINT, 0, G_PARAM_READWRITE | G_PARAM_STATIC_STRINGS));
  g_object_class_install_property (G_OBJECT_CLASS (klass), ARG_LUM_ONLY,
      g_param_spec_boolean ("lum-only", "lum-only", "lum-only", TRUE,
          G_PARAM_READWRITE | G_PARAM_STATIC_STRINGS));

  gobject_class->set_property = gst_median_set_property;
  gobject_class->get_property = gst_median_get_property;
}

static gboolean
gst_median_link (GstPad * pad, const GstCaps * caps)
{
  GstMedian *filter = GST_MEDIAN (gst_pad_get_parent (pad));
  GstPad *otherpad = (pad == filter->srcpad) ? filter->sinkpad : filter->srcpad;
  GstStructure *structure = gst_caps_get_structure (caps, 0);
  gint w, h;
  GstPadLinkReturn ret;

  gst_structure_get_int (structure, "width", &w);
  gst_structure_get_int (structure, "height", &h);

  ret = gst_pad_try_set_caps (otherpad, caps);
  if (GST_PAD_LINK_SUCCESSFUL (ret)) {
    filter->width = w;
    filter->height = h;
  }

  gst_object_unref (filter);

  return ret;
}

void
gst_median_init (GstMedian * median)
{
  median->sinkpad =
      gst_pad_new_from_static_template (&media_sink_factory, "sink");
  gst_pad_set_getcaps_function (median->sinkpad, gst_pad_proxy_getcaps);
  gst_pad_set_link_function (median->sinkpad, gst_median_link);
  gst_pad_set_chain_function (median->sinkpad, gst_median_chain);
  gst_element_add_pad (GST_ELEMENT (median), median->sinkpad);

  median->srcpad = gst_pad_new_from_static_template (&media_src_factory, "src");
  gst_pad_set_getcaps_function (median->srcpad, gst_pad_proxy_getcaps);
  gst_pad_set_link_function (median->sinkpad, gst_median_link);
  gst_element_add_pad (GST_ELEMENT (median), median->srcpad);

  median->filtersize = 5;
  median->lum_only = TRUE;
  median->active = TRUE;
}

#define PIX_SORT(a,b) { if ((a)>(b)) PIX_SWAP((a),(b)); }
#define PIX_SWAP(a,b) { unsigned char temp=(a);(a)=(b);(b)=temp; }

static void
median_5 (unsigned char *src, unsigned char *dest, int width, int height)
{
  int nLastRow;
  int nLastCol;
  unsigned char p[9];
  int i, j, k;

  nLastCol = width - 1;
  nLastRow = height - 1;

  /*copy the top and bottom rows into the result array */
  for (i = 0; i < width; i++) {
    dest[i] = src[i];
    dest[nLastRow * width + i] = src[nLastRow * width + i];
  }
  dest[i] = src[i];

  nLastCol--;
  nLastRow--;

  /* process the interior pixels */
  i = width + 1;
  for (k = 0; k < nLastRow; k++) {
    for (j = 0; j < nLastCol; j++, i++) {
      p[0] = src[i - width];
      p[1] = src[i - 1];
      p[2] = src[i];
      p[3] = src[i + 1];
      p[4] = src[i + width];
      PIX_SORT (p[0], p[1]);
      PIX_SORT (p[3], p[4]);
      PIX_SORT (p[0], p[3]);
      PIX_SORT (p[1], p[4]);
      PIX_SORT (p[1], p[2]);
      PIX_SORT (p[2], p[3]);
      PIX_SORT (p[1], p[2]);
      dest[i] = p[2];
    }
    dest[i] = src[i];
    i++;
    dest[i] = src[i];
    i++;
  }
  dest[i] = src[i];
  i++;
}

static void
median_9 (unsigned char *src, unsigned char *dest, int width, int height)
{
  int nLastRow;
  int nLastCol;
  unsigned char p[9];
  int i, j, k;

  nLastCol = width - 1;
  nLastRow = height - 1;

  /*copy the top and bottom rows into the result array */
  for (i = 0; i < width; i++) {
    dest[i] = src[i];
    dest[nLastRow * width + i] = src[nLastRow * width + i];
  }
  dest[i] = src[i];

  nLastCol--;
  nLastRow--;

  /* process the interior pixels */
  i = width + 1;
  for (k = 0; k < nLastRow; k++) {
    for (j = 0; j < nLastCol; j++, i++) {
      p[0] = src[i - width - 1];
      p[1] = src[i - width];
      p[2] = src[i - width + 1];
      p[3] = src[i - 1];
      p[4] = src[i];
      p[5] = src[i + 1];
      p[6] = src[i + width - 1];
      p[7] = src[i + width];
      p[8] = src[i + width + 1];
      PIX_SORT (p[1], p[2]);
      PIX_SORT (p[4], p[5]);
      PIX_SORT (p[7], p[8]);
      PIX_SORT (p[0], p[1]);
      PIX_SORT (p[3], p[4]);
      PIX_SORT (p[6], p[7]);
      PIX_SORT (p[1], p[2]);
      PIX_SORT (p[4], p[5]);
      PIX_SORT (p[7], p[8]);
      PIX_SORT (p[0], p[3]);
      PIX_SORT (p[5], p[8]);
      PIX_SORT (p[4], p[7]);
      PIX_SORT (p[3], p[6]);
      PIX_SORT (p[1], p[4]);
      PIX_SORT (p[2], p[5]);
      PIX_SORT (p[4], p[7]);
      PIX_SORT (p[4], p[2]);
      PIX_SORT (p[6], p[4]);
      PIX_SORT (p[4], p[2]);
      dest[i] = p[4];
    }
    dest[i] = src[i];
    i++;
    dest[i] = src[i];
    i++;
  }
  dest[i] = src[i];
  i++;
}

static void
gst_median_chain (GstPad * pad, GstData * _data)
{
  GstBuffer *buf = GST_BUFFER (_data);
  GstMedian *median;
  guchar *data;
  gulong size;
  GstBuffer *outbuf;

/*  GstMeta *meta; */
  int lumsize, chromsize;

  g_return_if_fail (pad != NULL);
  g_return_if_fail (GST_IS_PAD (pad));
  g_return_if_fail (buf != NULL);

  median = GST_MEDIAN (GST_OBJECT_PARENT (pad));

  if (!median->active) {
    gst_pad_push (median->srcpad, GST_DATA (buf));
    return;
  }

  data = GST_BUFFER_DATA (buf);
  size = GST_BUFFER_SIZE (buf);

  GST_DEBUG ("median: have buffer of %d", GST_BUFFER_SIZE (buf));

  outbuf = gst_buffer_new ();
  GST_BUFFER_DATA (outbuf) = g_malloc (GST_BUFFER_SIZE (buf));
  GST_BUFFER_SIZE (outbuf) = GST_BUFFER_SIZE (buf);

  lumsize = median->width * median->height;
  chromsize = lumsize / 4;

  if (median->filtersize == 5) {
    median_5 (data, GST_BUFFER_DATA (outbuf), median->width, median->height);
    if (!median->lum_only) {
      median_5 (data + lumsize, GST_BUFFER_DATA (outbuf) + lumsize,
          median->width / 2, median->height / 2);
      median_5 (data + lumsize + chromsize,
          GST_BUFFER_DATA (outbuf) + lumsize + chromsize, median->width / 2,
          median->height / 2);
    } else {
      memcpy (GST_BUFFER_DATA (outbuf) + lumsize, data + lumsize,
          chromsize * 2);
    }
  } else {
    median_9 (data, GST_BUFFER_DATA (outbuf), median->width, median->height);
    if (!median->lum_only) {
      median_9 (data + lumsize, GST_BUFFER_DATA (outbuf) + lumsize,
          median->width / 2, median->height / 2);
      median_9 (data + lumsize + chromsize,
          GST_BUFFER_DATA (outbuf) + lumsize + chromsize, median->width / 2,
          median->height / 2);
    } else {
      memcpy (GST_BUFFER_DATA (outbuf) + lumsize, data + lumsize,
          chromsize * 2);
    }
  }
  GST_BUFFER_TIMESTAMP (outbuf) = GST_BUFFER_TIMESTAMP (buf);

  gst_buffer_unref (buf);

  gst_pad_push (median->srcpad, GST_DATA (outbuf));
}

static void
gst_median_set_property (GObject * object, guint prop_id, const GValue * value,
    GParamSpec * pspec)
{
  GstMedian *median;
  gint argvalue;

  g_return_if_fail (GST_IS_MEDIAN (object));
  median = GST_MEDIAN (object);

  switch (prop_id) {
    case ARG_FILTERSIZE:
      argvalue = g_value_get_int (value);
      if (argvalue != 5 && argvalue != 9) {
        g_warning ("median: invalid filtersize (%d), must be 5 or 9\n",
            argvalue);
      } else {
        median->filtersize = argvalue;
      }
      break;
    case ARG_ACTIVE:
      median->active = g_value_get_boolean (value);
      break;
    case ARG_LUM_ONLY:
      median->lum_only = g_value_get_boolean (value);
      break;
    default:
      break;
  }
}

static void
gst_median_get_property (GObject * object, guint prop_id, GValue * value,
    GParamSpec * pspec)
{
  GstMedian *median;

  g_return_if_fail (GST_IS_MEDIAN (object));
  median = GST_MEDIAN (object);

  switch (prop_id) {
    case ARG_FILTERSIZE:
      g_value_set_int (value, median->filtersize);
      break;
    case ARG_ACTIVE:
      g_value_set_boolean (value, median->active);
      break;
    case ARG_LUM_ONLY:
      g_value_set_boolean (value, median->lum_only);
      break;
    default:
      G_OBJECT_WARN_INVALID_PROPERTY_ID (object, prop_id, pspec);
      break;
  }
}


static gboolean
plugin_init (GstPlugin * plugin)
{
  return gst_element_register (plugin, "median",
      GST_RANK_NONE, GST_TYPE_MEDIAN);
}

GST_PLUGIN_DEFINE (GST_VERSION_MAJOR,
    GST_VERSION_MINOR,
    median,
    "Video median filter",
    plugin_init, VERSION, GST_LICENSE, GST_PACKAGE_NAME, GST_PACKAGE_ORIGIN)