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/*
* GStreamer
* Copyright (C) 2010 Thiago Santos <thiago.sousa.santos@collabora.co.uk>
*
* Permission is hereby granted, free of charge, to any person obtaining a
* copy of this software and associated documentation files (the "Software"),
* to deal in the Software without restriction, including without limitation
* the rights to use, copy, modify, merge, publish, distribute, sublicense,
* and/or sell copies of the Software, and to permit persons to whom the
* Software is furnished to do so, subject to the following conditions:
*
* The above copyright notice and this permission notice shall be included in
* all copies or substantial portions of the Software.
*
* THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR
* IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY,
* FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT. IN NO EVENT SHALL THE
* AUTHORS OR COPYRIGHT HOLDERS BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER
* LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING
* FROM, OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER
* DEALINGS IN THE SOFTWARE.
*
* Alternatively, the contents of this file may be used under the
* GNU Lesser General Public License Version 2.1 (the "LGPL"), in
* which case the following provisions apply instead of the ones
* mentioned above:
*
* 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., 51 Franklin St, Fifth Floor,
* Boston, MA 02110-1301, USA.
*/
/*
* Thanks to Jerry Huxtable <http://www.jhlabs.com> work on its java
* image editor and filters. The algorithms here were extracted from
* his code.
*/
/**
* SECTION:element-twirl
* @title: twirl
* @see_also: geometrictransform
*
* The twirl element twists the image from the center out.
*
* ## Example launch line
* |[
* gst-launch-1.0 -v videotestsrc ! twirl ! videoconvert ! autovideosink
* ]|
*
*/
#ifdef HAVE_CONFIG_H
# include <config.h>
#endif
#include <gst/gst.h>
#include <math.h>
#include "gsttwirl.h"
GST_DEBUG_CATEGORY_STATIC (gst_twirl_debug);
#define GST_CAT_DEFAULT gst_twirl_debug
enum
{
PROP_0,
PROP_ANGLE
};
#define DEFAULT_ANGLE (G_PI)
#define gst_twirl_parent_class parent_class
G_DEFINE_TYPE (GstTwirl, gst_twirl, GST_TYPE_CIRCLE_GEOMETRIC_TRANSFORM);
GST_ELEMENT_REGISTER_DEFINE_WITH_CODE (twirl, "twirl", GST_RANK_NONE,
GST_TYPE_TWIRL, GST_DEBUG_CATEGORY_INIT (gst_twirl_debug, "twirl", 0,
"twirl"));
static void
gst_twirl_set_property (GObject * object, guint prop_id, const GValue * value,
GParamSpec * pspec)
{
GstTwirl *twirl;
GstGeometricTransform *gt;
gdouble v;
gt = GST_GEOMETRIC_TRANSFORM_CAST (object);
twirl = GST_TWIRL_CAST (object);
GST_OBJECT_LOCK (gt);
switch (prop_id) {
case PROP_ANGLE:
v = g_value_get_double (value);
if (v != twirl->angle) {
twirl->angle = v;
gst_geometric_transform_set_need_remap (gt);
}
break;
default:
G_OBJECT_WARN_INVALID_PROPERTY_ID (object, prop_id, pspec);
break;
}
GST_OBJECT_UNLOCK (gt);
}
static void
gst_twirl_get_property (GObject * object, guint prop_id,
GValue * value, GParamSpec * pspec)
{
GstTwirl *twirl;
twirl = GST_TWIRL_CAST (object);
switch (prop_id) {
case PROP_ANGLE:
g_value_set_double (value, twirl->angle);
break;
default:
G_OBJECT_WARN_INVALID_PROPERTY_ID (object, prop_id, pspec);
break;
}
}
static gboolean
twirl_map (GstGeometricTransform * gt, gint x, gint y, gdouble * in_x,
gdouble * in_y)
{
GstCircleGeometricTransform *cgt = GST_CIRCLE_GEOMETRIC_TRANSFORM_CAST (gt);
GstTwirl *twirl = GST_TWIRL_CAST (gt);
gdouble distance;
gdouble dx, dy;
dx = x - cgt->precalc_x_center;
dy = y - cgt->precalc_y_center;
distance = dx * dx + dy * dy;
if (distance > cgt->precalc_radius2) {
*in_x = x;
*in_y = y;
} else {
gdouble d = sqrt (distance);
gdouble a = atan2 (dy,
dx) + twirl->angle * (cgt->precalc_radius - d) / cgt->precalc_radius;
*in_x = cgt->precalc_x_center + d * cos (a);
*in_y = cgt->precalc_y_center + d * sin (a);
}
GST_DEBUG_OBJECT (twirl, "Inversely mapped %d %d into %lf %lf",
x, y, *in_x, *in_y);
return TRUE;
}
static void
gst_twirl_class_init (GstTwirlClass * klass)
{
GObjectClass *gobject_class;
GstElementClass *gstelement_class;
GstGeometricTransformClass *gstgt_class;
gobject_class = (GObjectClass *) klass;
gstelement_class = (GstElementClass *) klass;
gstgt_class = (GstGeometricTransformClass *) klass;
gst_element_class_set_static_metadata (gstelement_class,
"twirl",
"Transform/Effect/Video",
"Twists the image from the center out",
"Thiago Santos<thiago.sousa.santos@collabora.co.uk>");
gobject_class->set_property = gst_twirl_set_property;
gobject_class->get_property = gst_twirl_get_property;
g_object_class_install_property (gobject_class, PROP_ANGLE,
g_param_spec_double ("angle", "angle",
"This is the angle in radians by which pixels at the "
"nearest edge of the image will move",
-G_MAXDOUBLE, G_MAXDOUBLE, DEFAULT_ANGLE,
GST_PARAM_CONTROLLABLE | G_PARAM_READWRITE | G_PARAM_STATIC_STRINGS));
gstgt_class->map_func = twirl_map;
}
static void
gst_twirl_init (GstTwirl * filter)
{
GstGeometricTransform *gt = GST_GEOMETRIC_TRANSFORM (filter);
gt->off_edge_pixels = GST_GT_OFF_EDGES_PIXELS_CLAMP;
filter->angle = DEFAULT_ANGLE;
}
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