gstreamer/ext/opencv/gsthanddetect.c

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/*
* GStreamer hand gesture detection plugins
* Copyright (C) 2012 Andol Li <<andol@andol.info>>
* Copyright (C) 2013 Sreerenj Balachandran <sreerenj.balachandran@intel.com>
*
* 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., 59 Temple Place - Suite 330,
* Boston, MA 02111-1307, USA.
*/
/**
* SECTION:video-filter-handdetect
*
* FIXME:operates hand gesture detection in video streams and images,
* and enable media operation e.g. play/stop/fast forward/back rewind.
*
* <refsect2>
* <title>Example launch line</title>
* |[
* gst-launch-1.0 autovideosrc ! videoconvert ! "video/x-raw, formt=RGB, width=320, height=240" ! \
* videoscale ! handdetect ! videoconvert ! xvimagesink
* ]|
* </refsect2>
*/
#ifdef HAVE_CONFIG_H
#include <config.h>
#endif
/* element header */
#include "gsthanddetect.h"
#include "gstopencvutils.h"
GST_DEBUG_CATEGORY_STATIC (gst_handdetect_debug);
#define GST_CAT_DEFAULT gst_handdetect_debug
/* define HAAR files */
#define HAAR_FILE_FIST GST_HAAR_CASCADES_DIR G_DIR_SEPARATOR_S "fist.xml"
#define HAAR_FILE_PALM GST_HAAR_CASCADES_DIR G_DIR_SEPARATOR_S "palm.xml"
/* Filter signals and args */
enum
{
/* FILL ME */
LAST_SIGNAL
};
enum
{
PROP_0,
PROP_DISPLAY,
PROP_PROFILE_FIST,
PROP_PROFILE_PALM,
PROP_ROI_X,
PROP_ROI_Y,
PROP_ROI_WIDTH,
PROP_ROI_HEIGHT
};
/* the capabilities of the inputs and outputs */
static GstStaticPadTemplate sink_factory = GST_STATIC_PAD_TEMPLATE ("sink",
GST_PAD_SINK,
GST_PAD_ALWAYS,
GST_STATIC_CAPS (GST_VIDEO_CAPS_MAKE ("RGB"))
);
static GstStaticPadTemplate src_factory = GST_STATIC_PAD_TEMPLATE ("src",
GST_PAD_SRC,
GST_PAD_ALWAYS,
GST_STATIC_CAPS (GST_VIDEO_CAPS_MAKE ("RGB"))
);
static void gst_handdetect_set_property (GObject * object, guint prop_id,
const GValue * value, GParamSpec * pspec);
static void gst_handdetect_get_property (GObject * object, guint prop_id,
GValue * value, GParamSpec * pspec);
static gboolean gst_handdetect_set_caps (GstOpencvVideoFilter * transform,
gint in_width, gint in_height, gint in_depth, gint in_channels,
gint out_width, gint out_height, gint out_depth, gint out_channels);
static GstFlowReturn gst_handdetect_transform_ip (GstOpencvVideoFilter *
transform, GstBuffer * buffer, IplImage * img);
static void gst_handdetect_load_profile (GstHanddetect * filter);
static void gst_handdetect_navigation_interface_init (GstNavigationInterface *
iface);
static void gst_handdetect_navigation_send_event (GstNavigation * navigation,
GstStructure * structure);
G_DEFINE_TYPE_WITH_CODE (GstHanddetect, gst_handdetect,
GST_TYPE_OPENCV_VIDEO_FILTER,
G_IMPLEMENT_INTERFACE (GST_TYPE_NAVIGATION,
gst_handdetect_navigation_interface_init););
static void
gst_handdetect_navigation_interface_init (GstNavigationInterface * iface)
{
iface->send_event = gst_handdetect_navigation_send_event;
}
/* FIXME: this function used to parse the region of interests coordinates
* sending from applications when the hand gestures reach the defined regions of interests,
* at this moment this function is not doing anything significantly
* but will be CHANGED when the gstreamer is patched with new hand gesture events
*/
static void
gst_handdetect_navigation_send_event (GstNavigation * navigation,
GstStructure * structure)
{
GstHanddetect *filter = GST_HANDDETECT (navigation);
GstPad *peer;
if ((peer = gst_pad_get_peer (GST_BASE_TRANSFORM_CAST (filter)->sinkpad))) {
GstEvent *event;
event = gst_event_new_navigation (structure);
gst_pad_send_event (peer, event);
gst_object_unref (peer);
}
}
/* clean opencv images and parameters */
static void
gst_handdetect_finalize (GObject * obj)
{
GstHanddetect *filter = GST_HANDDETECT (obj);
if (filter->cvImage)
cvReleaseImage (&filter->cvImage);
if (filter->cvGray)
cvReleaseImage (&filter->cvGray);
g_free (filter->profile_fist);
g_free (filter->profile_palm);
G_OBJECT_CLASS (gst_handdetect_parent_class)->finalize (obj);
}
/* initialise the HANDDETECT class */
static void
gst_handdetect_class_init (GstHanddetectClass * klass)
{
GObjectClass *gobject_class;
GstOpencvVideoFilterClass *gstopencvbasefilter_class;
GstElementClass *element_class = GST_ELEMENT_CLASS (klass);
gobject_class = (GObjectClass *) klass;
gstopencvbasefilter_class = (GstOpencvVideoFilterClass *) klass;
gstopencvbasefilter_class->cv_trans_ip_func = gst_handdetect_transform_ip;
gstopencvbasefilter_class->cv_set_caps = gst_handdetect_set_caps;
gobject_class->finalize = GST_DEBUG_FUNCPTR (gst_handdetect_finalize);
gobject_class->set_property = gst_handdetect_set_property;
gobject_class->get_property = gst_handdetect_get_property;
g_object_class_install_property (gobject_class,
PROP_DISPLAY,
g_param_spec_boolean ("display",
"Display",
"Whether the detected hands are highlighted in output frame",
TRUE, G_PARAM_READWRITE)
);
g_object_class_install_property (gobject_class,
PROP_PROFILE_FIST,
g_param_spec_string ("profile_fist",
"Profile_fist",
"Location of HAAR cascade file (fist gesture)",
HAAR_FILE_FIST, G_PARAM_READWRITE)
);
g_object_class_install_property (gobject_class,
PROP_PROFILE_PALM,
g_param_spec_string ("profile_palm",
"Profile_palm",
"Location of HAAR cascade file (palm gesture)",
HAAR_FILE_PALM, G_PARAM_READWRITE)
);
/* FIXME: property name needs fixing */
g_object_class_install_property (gobject_class,
PROP_ROI_X,
g_param_spec_uint ("ROI_X",
"ROI_X",
"X of left-top pointer in region of interest \nGestures in the defined region of interest will emit messages",
0, UINT_MAX, 0, G_PARAM_READWRITE)
);
/* FIXME: property name needs fixing */
g_object_class_install_property (gobject_class,
PROP_ROI_Y,
g_param_spec_uint ("ROI_Y",
"ROI_Y",
"Y of left-top pointer in region of interest \nGestures in the defined region of interest will emit messages",
0, UINT_MAX, 0, G_PARAM_READWRITE)
);
/* FIXME: property name needs fixing */
g_object_class_install_property (gobject_class,
PROP_ROI_WIDTH,
g_param_spec_uint ("ROI_WIDTH",
"ROI_WIDTH",
"WIDTH of left-top pointer in region of interest \nGestures in the defined region of interest will emit messages",
0, UINT_MAX, 0, G_PARAM_READWRITE)
);
/* FIXME: property name needs fixing */
g_object_class_install_property (gobject_class,
PROP_ROI_HEIGHT,
g_param_spec_uint ("ROI_HEIGHT",
"ROI_HEIGHT",
"HEIGHT of left-top pointer in region of interest \nGestures in the defined region of interest will emit messages",
0, UINT_MAX, 0, G_PARAM_READWRITE)
);
gst_element_class_set_static_metadata (element_class,
"handdetect",
"Filter/Effect/Video",
"Performs hand gesture detection on videos, providing detected hand positions via bus message and navigation event, and deals with hand gesture events",
"Andol Li <andol@andol.info>");
gst_element_class_add_pad_template (element_class,
gst_static_pad_template_get (&src_factory));
gst_element_class_add_pad_template (element_class,
gst_static_pad_template_get (&sink_factory));
}
/* initialise the new element
* instantiate pads and add them to element
* set pad call-back functions
* initialise instance structure
*/
static void
gst_handdetect_init (GstHanddetect * filter)
{
filter->profile_fist = g_strdup (HAAR_FILE_FIST);
filter->profile_palm = g_strdup (HAAR_FILE_PALM);
filter->roi_x = 0;
filter->roi_y = 0;
filter->roi_width = 0;
filter->roi_height = 0;
filter->display = TRUE;
gst_handdetect_load_profile (filter);
gst_opencv_video_filter_set_in_place (GST_OPENCV_VIDEO_FILTER_CAST (filter),
TRUE);
}
static void
gst_handdetect_set_property (GObject * object, guint prop_id,
const GValue * value, GParamSpec * pspec)
{
GstHanddetect *filter = GST_HANDDETECT (object);
switch (prop_id) {
case PROP_PROFILE_FIST:
g_free (filter->profile_fist);
filter->profile_fist = g_value_dup_string (value);
gst_handdetect_load_profile (filter);
break;
case PROP_PROFILE_PALM:
g_free (filter->profile_palm);
filter->profile_palm = g_value_dup_string (value);
gst_handdetect_load_profile (filter);
break;
case PROP_DISPLAY:
filter->display = g_value_get_boolean (value);
break;
case PROP_ROI_X:
filter->roi_x = g_value_get_uint (value);
break;
case PROP_ROI_Y:
filter->roi_y = g_value_get_uint (value);
break;
case PROP_ROI_WIDTH:
filter->roi_width = g_value_get_uint (value);
break;
case PROP_ROI_HEIGHT:
filter->roi_height = g_value_get_uint (value);
break;
default:
G_OBJECT_WARN_INVALID_PROPERTY_ID (object, prop_id, pspec);
break;
}
}
static void
gst_handdetect_get_property (GObject * object, guint prop_id, GValue * value,
GParamSpec * pspec)
{
GstHanddetect *filter = GST_HANDDETECT (object);
switch (prop_id) {
case PROP_DISPLAY:
g_value_set_boolean (value, filter->display);
break;
case PROP_PROFILE_FIST:
g_value_set_string (value, filter->profile_fist);
break;
case PROP_PROFILE_PALM:
g_value_set_string (value, filter->profile_palm);
break;
case PROP_ROI_X:
g_value_set_uint (value, filter->roi_x);
break;
case PROP_ROI_Y:
g_value_set_uint (value, filter->roi_y);
break;
case PROP_ROI_WIDTH:
g_value_set_uint (value, filter->roi_width);
break;
case PROP_ROI_HEIGHT:
g_value_set_uint (value, filter->roi_height);
break;
default:
G_OBJECT_WARN_INVALID_PROPERTY_ID (object, prop_id, pspec);
break;
}
}
/* GstElement vmethod implementations */
/* this function handles the link with other elements */
static gboolean
gst_handdetect_set_caps (GstOpencvVideoFilter * transform,
gint in_width, gint in_height, gint in_depth, gint in_channels,
gint out_width, gint out_height, gint out_depth, gint out_channels)
{
GstHanddetect *filter;
filter = GST_HANDDETECT (transform);
if (filter->cvGray)
cvReleaseImage (&filter->cvGray);
filter->cvGray =
cvCreateImage (cvSize (in_width, in_height), IPL_DEPTH_8U, 1);
if (filter->cvImage)
cvReleaseImage (&filter->cvImage);
filter->cvImage =
cvCreateImage (cvSize (in_width, in_height), IPL_DEPTH_8U, 3);
if (!filter->cvStorage)
filter->cvStorage = cvCreateMemStorage (0);
else
cvClearMemStorage (filter->cvStorage);
if (!filter->cvStorage_palm)
filter->cvStorage_palm = cvCreateMemStorage (0);
else
cvClearMemStorage (filter->cvStorage_palm);
return TRUE;
}
/* Hand detection function
* This function does the actual processing 'of hand detect and display'
*/
static GstFlowReturn
gst_handdetect_transform_ip (GstOpencvVideoFilter * transform,
GstBuffer * buffer, IplImage * img)
{
GstHanddetect *filter = GST_HANDDETECT (transform);
GstMapInfo info;
CvSeq *hands;
CvRect *r;
GstStructure *s;
GstMessage *m;
int i;
buffer = gst_buffer_make_writable (buffer);
gst_buffer_map (buffer, &info, GST_MAP_READWRITE);
filter->cvImage->imageData = (char *) info.data;
/* 320 x 240 is with the best detect accuracy, if not, give info */
if (filter->cvImage->width != 320 || filter->cvImage->height != 240)
GST_INFO_OBJECT (filter,
"WARNING: resize to 320 x 240 to have best detect accuracy.\n");
/* cvt to gray colour space for hand detect */
cvCvtColor (filter->cvImage, filter->cvGray, CV_RGB2GRAY);
cvClearMemStorage (filter->cvStorage);
/* check detection cascades */
if (!filter->cvCascade_fist || !filter->cvCascade_palm)
return GST_FLOW_OK;
/* detect FIST gesture fist */
hands =
cvHaarDetectObjects (filter->cvGray, filter->cvCascade_fist,
filter->cvStorage, 1.1, 2, CV_HAAR_DO_CANNY_PRUNING, cvSize (24, 24)
#if (CV_MAJOR_VERSION >= 2) && (CV_MINOR_VERSION >= 2)
, cvSize (0, 0)
#endif
);
/* if FIST gesture detected */
if (hands && hands->total > 0) {
int min_distance, distance;
CvRect temp_r;
CvPoint c;
/* set frame buffer writable */
if (filter->display) {
buffer = gst_buffer_make_writable (buffer);
GST_DEBUG_OBJECT (filter, "%d FIST gestures detected\n",
(int) hands->total);
}
/* Go through all detected FIST gestures to get the best one
* prev_r => previous hand
* best_r => best hand in this frame
*/
/* set min_distance for init comparison */
min_distance = filter->cvImage->width + filter->cvImage->height;
/* Init filter->prev_r */
temp_r = cvRect (0, 0, 0, 0);
if (filter->prev_r == NULL)
filter->prev_r = &temp_r;
/* Get the best FIST gesture */
for (i = 0; i < (hands ? hands->total : 0); i++) {
r = (CvRect *) cvGetSeqElem (hands, i);
distance = (int) sqrt (pow ((r->x - filter->prev_r->x),
2) + pow ((r->y - filter->prev_r->y), 2));
if (distance <= min_distance) {
min_distance = distance;
filter->best_r = r;
}
}
/* Save best_r as prev_r for next frame comparison */
filter->prev_r = (CvRect *) filter->best_r;
/* send msg to app/bus if the detected gesture falls in the region of interest */
/* get center point of gesture */
c = cvPoint (filter->best_r->x + filter->best_r->width / 2,
filter->best_r->y + filter->best_r->height / 2);
/* send message:
* if the center point is in the region of interest, OR,
* if the region of interest remains default as (0,0,0,0)*/
if ((c.x >= filter->roi_x && c.x <= (filter->roi_x + filter->roi_width)
&& c.y >= filter->roi_y
&& c.y <= (filter->roi_y + filter->roi_height))
|| (filter->roi_x == 0
&& filter->roi_y == 0
&& filter->roi_width == 0 && filter->roi_height == 0)) {
/* Define structure for message post */
s = gst_structure_new ("hand-gesture",
"gesture", G_TYPE_STRING, "fist",
"x", G_TYPE_UINT,
(uint) (filter->best_r->x + filter->best_r->width * 0.5), "y",
G_TYPE_UINT,
(uint) (filter->best_r->y + filter->best_r->height * 0.5), "width",
G_TYPE_UINT, (uint) filter->best_r->width, "height", G_TYPE_UINT,
(uint) filter->best_r->height, NULL);
/* Init message element */
m = gst_message_new_element (GST_OBJECT (filter), s);
/* Send message */
gst_element_post_message (GST_ELEMENT (filter), m);
#if 0
/* send event
* here we use mouse-move event instead of fist-move or palm-move event
* !!! this will CHANGE in the future !!!
* !!! by adding gst_navigation_send_hand_detect_event() in navigation.c !!!
*/
gst_navigation_send_mouse_event (GST_NAVIGATION (filter),
"mouse-move",
0,
(double) (filter->best_r->x + filter->best_r->width * 0.5),
(double) (filter->best_r->y + filter->best_r->height * 0.5));
#endif
}
/* Check filter->display,
* If TRUE, displaying red circle marker in the out frame */
if (filter->display) {
CvPoint center;
int radius;
center.x = cvRound ((filter->best_r->x + filter->best_r->width * 0.5));
center.y = cvRound ((filter->best_r->y + filter->best_r->height * 0.5));
radius =
cvRound ((filter->best_r->width + filter->best_r->height) * 0.25);
cvCircle (filter->cvImage, center, radius, CV_RGB (0, 0, 200), 1, 8, 0);
}
} else {
/* if NO FIST gesture, detecting PALM gesture */
hands =
cvHaarDetectObjects (filter->cvGray, filter->cvCascade_palm,
filter->cvStorage, 1.1, 3, CV_HAAR_DO_CANNY_PRUNING, cvSize (24, 24)
#if (CV_MAJOR_VERSION >= 2) && (CV_MINOR_VERSION >= 2)
, cvSize (0, 0)
#endif
);
/* if PALM detected */
if (hands && hands->total > 0) {
int min_distance, distance;
CvRect temp_r;
CvPoint c;
/* set frame buffer writable */
if (filter->display) {
buffer = gst_buffer_make_writable (buffer);
GST_DEBUG_OBJECT (filter, "%d PALM gestures detected\n",
(int) hands->total);
}
/* Go through all detected PALM gestures to get the best one
* prev_r => previous hand
* best_r => best hand in this frame
*/
/* suppose a min_distance for init comparison */
min_distance = filter->cvImage->width + filter->cvImage->height;
/* Init filter->prev_r */
temp_r = cvRect (0, 0, 0, 0);
if (filter->prev_r == NULL)
filter->prev_r = &temp_r;
/* Get the best PALM gesture */
for (i = 0; i < (hands ? hands->total : 0); i++) {
r = (CvRect *) cvGetSeqElem (hands, i);
distance = (int) sqrt (pow ((r->x - filter->prev_r->x),
2) + pow ((r->y - filter->prev_r->y), 2));
if (distance <= min_distance) {
min_distance = distance;
filter->best_r = r;
}
}
/* Save best_r as prev_r for next frame comparison */
filter->prev_r = (CvRect *) filter->best_r;
/* send msg to app/bus if the detected gesture falls in the region of interest */
/* get center point of gesture */
c = cvPoint (filter->best_r->x + filter->best_r->width / 2,
filter->best_r->y + filter->best_r->height / 2);
/* send message:
* if the center point is in the region of interest, OR,
* if the region of interest remains default as (0,0,0,0)*/
if ((c.x >= filter->roi_x && c.x <= (filter->roi_x + filter->roi_width)
&& c.y >= filter->roi_y
&& c.y <= (filter->roi_y + filter->roi_height))
|| (filter->roi_x == 0
&& filter->roi_y == 0
&& filter->roi_width == 0 && filter->roi_height == 0)) {
/* Define structure for message post */
s = gst_structure_new ("hand-gesture",
"gesture", G_TYPE_STRING, "palm",
"x", G_TYPE_UINT,
(uint) (filter->best_r->x + filter->best_r->width * 0.5), "y",
G_TYPE_UINT,
(uint) (filter->best_r->y + filter->best_r->height * 0.5), "width",
G_TYPE_UINT, (uint) filter->best_r->width, "height", G_TYPE_UINT,
(uint) filter->best_r->height, NULL);
/* Init message element */
m = gst_message_new_element (GST_OBJECT (filter), s);
/* Send message */
gst_element_post_message (GST_ELEMENT (filter), m);
#if 0
/* send event
* here we use mouse-move event instead of fist-move or palm-move event
* !!! this will CHANGE in the future !!!
* !!! by adding gst_navigation_send_hand_detect_event() in navigation.c !!!
*/
gst_navigation_send_mouse_event (GST_NAVIGATION (filter),
"mouse-move",
0,
(double) (filter->best_r->x + filter->best_r->width * 0.5),
(double) (filter->best_r->y + filter->best_r->height * 0.5));
/* or use another way to send upstream navigation event for debug
*
* GstEvent *event =
* gst_event_new_navigation (gst_structure_new
* ("application/x-gst-navigation", "event", G_TYPE_STRING,
* "mouse-move",
* "button", G_TYPE_INT, 0,
* "pointer_x", G_TYPE_DOUBLE,
* (double) (filter->best_r->x + filter->best_r->width * 0.5),
* "pointer_y", G_TYPE_DOUBLE,
* (double) (filter->best_r->y + filter->best_r->height * 0.5),
* NULL));
* gst_pad_send_event (GST_BASE_TRANSFORM_CAST (filter)->srcpad, event);
*/
#endif
}
/* Check filter->display,
* If TRUE, displaying red circle marker in the out frame */
if (filter->display) {
CvPoint center;
int radius;
center.x = cvRound ((filter->best_r->x + filter->best_r->width * 0.5));
center.y = cvRound ((filter->best_r->y + filter->best_r->height * 0.5));
radius =
cvRound ((filter->best_r->width + filter->best_r->height) * 0.25);
cvCircle (filter->cvImage, center, radius, CV_RGB (0, 0, 200), 1, 8, 0);
}
}
}
gst_buffer_unmap (buffer, &info);
/* Push out the incoming buffer */
return GST_FLOW_OK;
}
static void
gst_handdetect_load_profile (GstHanddetect * filter)
{
GST_DEBUG_OBJECT (filter, "Loading profiles...\n");
filter->cvCascade_fist =
(CvHaarClassifierCascade *) cvLoad (filter->profile_fist, 0, 0, 0);
filter->cvCascade_palm =
(CvHaarClassifierCascade *) cvLoad (filter->profile_palm, 0, 0, 0);
if (!filter->cvCascade_fist || !filter->cvCascade_palm)
GST_WARNING_OBJECT (filter,
"WARNING: Could not load HAAR classifier cascade: %s.\n",
filter->profile_fist);
else
GST_DEBUG_OBJECT (filter, "Loaded profile %s\n", filter->profile_fist);
if (!filter->cvCascade_palm)
GST_WARNING_OBJECT (filter,
"WARNING: Could not load HAAR classifier cascade: %s.\n",
filter->profile_palm);
else
GST_DEBUG_OBJECT (filter, "Loaded profile %s\n", filter->profile_palm);
}
/* Entry point to initialize the plug-in
* Initialize the plug-in itself
* Register the element factories and other features
*/
gboolean
gst_handdetect_plugin_init (GstPlugin * plugin)
{
GST_DEBUG_CATEGORY_INIT (gst_handdetect_debug,
"handdetect", 0, "opencv hand gesture detection");
return gst_element_register (plugin, "handdetect", GST_RANK_NONE,
GST_TYPE_HANDDETECT);
}