opencv: add handdetect plugin, initial implementation

The handdetect plugin is for detecting hand gestures using
opencv.

It was created in the course of the Google Summer of Code.

https://bugzilla.gnome.org/show_bug.cgi?id=685655

1 files changed, 174 insertions, 0 deletions

diff --git a/tests/examples/opencv/gsthanddetect_test.c b/tests/examples/opencv/gsthanddetect_test.c
new file mode 100644
index 000000000..2a2187bb7
--- /dev/null
+++ b/tests/examples/opencv/gsthanddetect_test.c
@@ -0,0 +1,174 @@
+/*
+ *============================================================================
+ *Name        : gsthanddetect_app.c
+ *Author      : Andol Li, andol@andol.info
+ *Version     : 0.1
+ *Copyright   : @2012, gstreamer
+ *Description : gsteramer handdetect plugin demo application in C, part work of GSoc 2012 project
+ *============================================================================
+ */
+
+#include <stdio.h>
+#include <stdlib.h>
+#include <string.h>
+#include <gst/gst.h>
+#include <glib.h>
+#include <glib-object.h>
+
+#define PROFILE_FIST "/usr/local/share/opencv/haarcascades/fist.xml"
+#define PROFILE_PALM "/usr/local/share/opencv/haarcascades/palm.xml"
+
+GstElement *playbin,
+			*pipeline,
+			*v4l2src, *videoscale, *ffmpegcolorspace_in, *handdetect, *ffmpegcolorspace_out, *xvimagesink;
+
+static GstBusSyncHandler
+bus_sync_handler(GstBus *bus, GstMessage *message, GstPipeline *pipeline)
+{
+	/* select msg */
+	if(GST_MESSAGE_TYPE (message) != GST_MESSAGE_ELEMENT ||
+			!gst_structure_has_name(message->structure, "hand-gesture") )
+		return GST_BUS_PASS;
+
+	/* parse msg structure */
+	const GstStructure *structure = message->structure;
+
+		/* if PALM gesture detected */
+		if (structure &&
+				strcmp (gst_structure_get_name (structure), "hand-gesture") == 0 &&
+				strcmp (gst_structure_get_string (structure, "gesture"), "palm") == 0) {
+			/* media operation - closed palm to stop media play*/
+			gst_element_set_state (playbin, GST_STATE_PAUSED);
+		}
+
+		/* if FIST gesture detected */
+		if (structure &&
+				strcmp (gst_structure_get_name (structure), "hand-gesture") == 0 &&
+				strcmp (gst_structure_get_string (structure, "gesture"), "fist") == 0){
+			/* print message type and structure name */
+			g_print("%s{{%s}}\n",	gst_message_type_get_name(message->type), gst_structure_get_name(structure));
+			/* print msg structure names&values */
+			int i;
+			for(i = 0; i < gst_structure_n_fields(structure); i++){
+				const gchar *name = gst_structure_nth_field_name(structure, i);
+				GType type = gst_structure_get_field_type(structure, name);
+				const GValue *value = gst_structure_get_value(structure, name);
+				type == G_TYPE_STRING ?
+						g_print("-%s[%s]{%s}\n", name, g_type_name(type), g_value_get_string(value)) :
+						g_print("-%s[%s]{%d}\n", name, g_type_name(type), g_value_get_uint(value));
+			}
+			g_print("\n");
+
+			/* get X,Y positions in frame */
+			const GValue *x_value = gst_structure_get_value(structure, "x");
+			gint x = g_value_get_uint(x_value);
+			const GValue *y_value = gst_structure_get_value(structure, "y");
+			gint y = g_value_get_uint(y_value);
+
+			/* set object volumes [0-10] based on Y */
+			g_object_set(G_OBJECT(playbin), "volume", (gdouble)(10 - y/24 ), NULL);
+
+			/* seek playback positions */
+			gint64 position, length;
+			GstFormat format = GST_FORMAT_TIME;
+			gst_element_query_duration(playbin, &format, &length);
+			/* Width = 320 is specified in caps */
+			position = (gint64) length * x / 320;
+			gst_element_set_state(playbin, GST_STATE_PAUSED);
+			gst_element_seek(GST_ELEMENT(playbin),
+					1.0,
+					format,
+					GST_SEEK_FLAG_FLUSH,
+					GST_SEEK_TYPE_SET,
+					position,
+					GST_SEEK_TYPE_NONE,
+					GST_CLOCK_TIME_NONE );
+			gst_element_set_state(GST_ELEMENT(playbin), GST_STATE_PLAYING);
+		}
+
+	gst_message_unref(message);
+	return GST_BUS_DROP;
+}
+
+int main(gint argc, gchar **argv) {
+	static GMainLoop *loop;
+	loop = g_main_loop_new(NULL, FALSE);
+	/* video source */
+	gchar *video_device = "/dev/video0";
+	gchar *video_file = "file:///home/javauser/workspace/gitfiles/gsthanddetect_app/video.avi";
+	/* bus */
+	GstBus *bus;
+	/* caps */
+	GstCaps *caps;
+
+	/* init gst */
+	gst_init(&argc, &argv);
+
+	/* init elements */
+	playbin = gst_element_factory_make("playbin2", "app_playbin");
+	pipeline = gst_pipeline_new("app_pipeline");
+	v4l2src = gst_element_factory_make("v4l2src", "app_v4l2src");
+	videoscale = gst_element_factory_make("videoscale", "app_videoscale");
+	ffmpegcolorspace_in = gst_element_factory_make("ffmpegcolorspace", "app_ffmpegcolorspace_in");
+	handdetect = gst_element_factory_make("handdetect", "app_handdetect");
+	ffmpegcolorspace_out = gst_element_factory_make("ffmpegcolorspace", "app_ffmpegcolorspace_out");
+	xvimagesink = gst_element_factory_make("xvimagesink", "app_xvimagesink");
+
+	/* check init results */
+	if(!playbin || !pipeline || !v4l2src || !videoscale || !ffmpegcolorspace_in
+			|| !handdetect || !ffmpegcolorspace_out || !xvimagesink)
+		g_error("ERROR: element init failed.\n");
+
+	/* set values */
+	g_object_set (G_OBJECT(playbin), "uri", video_file, NULL);
+	g_object_set (G_OBJECT(v4l2src), "device", video_device, NULL);
+	g_object_set (G_OBJECT (handdetect), "profile_fist", PROFILE_FIST, NULL);
+	g_object_set (G_OBJECT (handdetect), "profile_palm", PROFILE_PALM, NULL);
+
+	/* set caps */
+	caps = gst_caps_from_string("video/x-raw-rgb, width=320, height=240, framerate=(fraction)30/1");
+
+	/* set bus */
+	bus = gst_pipeline_get_bus(GST_PIPELINE(pipeline));
+	gst_bus_set_sync_handler(bus, (GstBusSyncHandler) bus_sync_handler, pipeline);
+	gst_object_unref(bus);
+
+	/* add elements to pipeline */
+	gst_bin_add_many(GST_BIN(pipeline),
+			v4l2src,
+			videoscale,
+			ffmpegcolorspace_in,
+			handdetect,
+			ffmpegcolorspace_out,
+			xvimagesink,
+			NULL);
+
+	/* negotiate caps */
+	if(!gst_element_link_filtered( v4l2src, videoscale, caps)){
+			g_printerr("ERROR:v4l2src -> videoscale caps\n");
+			return 0; }
+	gst_caps_unref(caps);
+
+	/* link elements */
+	gst_element_link_many(
+			videoscale,
+			ffmpegcolorspace_in,
+			handdetect,
+			ffmpegcolorspace_out,
+			xvimagesink,
+			NULL);
+
+	/* change states */
+	gst_element_set_state(pipeline, GST_STATE_PLAYING);
+
+	/* start main loop */
+	g_main_loop_run(loop);
+
+	/* clean all */
+	gst_element_set_state(pipeline, GST_STATE_NULL);
+	gst_object_unref(GST_OBJECT(pipeline));
+	gst_element_set_state(playbin, GST_STATE_NULL);
+	gst_object_unref(GST_OBJECT(playbin));
+
+	return 0;
+}