video_fuser.c

#include <gst/gst.h>

int main(int argc, char *argv[]) {
		GstBus *bus;
		GstMessage *msg;
		GstStateChangeReturn ret;
		GstElement *pipeline ,*comp,*video_test_src, *v4l2_src, *nvvidconv1, *nvvidconv2, *nvvidconv3, *video_convert, *main_sink, *vts_filter,*nvv1_filter,*nvv2_filter,*nvc1_filter,*vc_filter;

		/* Initialize GStreamer */
		gst_init(&argc, &argv);

		/* Create the elements */
		pipeline = gst_pipeline_new("video-pipeline");
		//compositor
		comp = gst_element_factory_make("nvcompositor", "comp");
		//sources
		video_test_src = gst_element_factory_make("videotestsrc", "video_test_src");
		v4l2_src = gst_element_factory_make("v4l2src", "v4l2_src");
		//capfilters	
		vts_filter = gst_element_factory_make("capsfilter","vts_filter");
		nvv1_filter = gst_element_factory_make("capsfilter","nvv1_filter");
		nvv2_filter = gst_element_factory_make("capsfilter","nvv2_filter");
		nvc1_filter = gst_element_factory_make("capsfilter","nvc1_filter");
		vc_filter = gst_element_factory_make("capsfilter","nvc2_filter");

		//converters
		nvvidconv1 = gst_element_factory_make("nvvidconv", "nvvidconv1");
		nvvidconv2 = gst_element_factory_make("nvvidconv", "nvvidconv2");
		nvvidconv3 = gst_element_factory_make("nvvidconv", "nvvidconv3");
		video_convert = gst_element_factory_make("videoconvert", "video_convert"); // Convert to non-NVMM format
		//sink
		main_sink = gst_element_factory_make("xvimagesink", "main_sink");

		/* Check elements creation */
		if (!pipeline || !comp || !video_test_src || !v4l2_src || !nvvidconv1 || !nvvidconv2 || !nvvidconv3 || !video_convert || !main_sink || !vts_filter || !nvv1_filter|| !nvv2_filter || !nvc1_filter || !vc_filter) {
				g_printerr("One or more elements could not be created. Exiting.\n");
				return -1;
		}


		GstCaps *rgba_caps_3 = gst_caps_new_simple("video/x-raw",
						"memory", G_TYPE_STRING, "NVMM",
						"format", G_TYPE_STRING, "RGBA",
						NULL);
		g_object_set (G_OBJECT (nvv1_filter), "caps", rgba_caps_3, NULL);
		g_object_set (G_OBJECT (nvc1_filter), "caps", rgba_caps_3, NULL);
		gst_caps_unref (rgba_caps_3);

		GstCaps *rgba_wh_caps_4 = gst_caps_new_simple("video/x-raw",
						"memory", G_TYPE_STRING, "NVMM",
						"format", G_TYPE_STRING, "RGBA",
						"width", G_TYPE_INT, 480,
						"height", G_TYPE_INT, 360,
						NULL);
		g_object_set (G_OBJECT (nvv2_filter), "caps", rgba_wh_caps_4, NULL);
		gst_caps_unref (rgba_wh_caps_4);

		GstCaps *yuv_wh_caps_2 = gst_caps_new_simple("video/x-raw",
						"format", G_TYPE_STRING, "YUY2",
						"width", G_TYPE_INT, 480,
						"height", G_TYPE_INT, 360,
						"framerate", GST_TYPE_FRACTION, 30, 1,
						NULL);
		g_object_set (G_OBJECT (vts_filter), "caps", yuv_wh_caps_2, NULL);
		gst_caps_unref (yuv_wh_caps_2);

		GstCaps *rgba_caps_1 = gst_caps_new_simple("video/x-raw",
						"format", G_TYPE_STRING, "RGBA",
						NULL);
		g_object_set (G_OBJECT (vc_filter), "caps", rgba_caps_1, NULL);
		gst_caps_unref (rgba_caps_1);
		
		#ifdef USE_PAD_LINK_METHOD
		/* Set properties for the compositor sink_0 */
		GstPad *comp_src_0_pad = gst_element_get_static_pad(comp, "src");


		GstPad *v4l2src_src_pad =  gst_element_get_static_pad(v4l2_src, "src");

		GstPad *videotestsrc_src_pad =  gst_element_get_static_pad(video_test_src, "src");

		GstPad *conv1_sink_pad = gst_element_get_static_pad(nvvidconv1, "sink");
		GstPad *conv1_src_pad =  gst_element_get_static_pad(nvvidconv1, "src");
		//		gst_pad_use_fixed_caps(conv1_sink_pad);

		GstPad *conv2_sink_pad = gst_element_get_static_pad(nvvidconv2, "sink");
		GstPad *conv2_src_pad =  gst_element_get_static_pad(nvvidconv2, "src");

		GstPad *conv3_sink_pad = gst_element_get_static_pad(nvvidconv3, "sink");
		GstPad *conv3_src_pad =  gst_element_get_static_pad(nvvidconv3, "src");


		GstPad *video_convert_sink_pad = gst_element_get_static_pad(video_convert, "sink");
		GstPad *video_convert_src_pad =  gst_element_get_static_pad(video_convert, "src");

		GstPad *main_sink_sink_pad = gst_element_get_static_pad(main_sink, "sink");
#endif
		GstPad *nvv1_filter_src_pad =  gst_element_get_static_pad(nvv1_filter, "src");
		GstPad *nvv2_filter_src_pad =  gst_element_get_static_pad(nvv2_filter, "src");
		
		GstPad *comp_sink_0_pad = gst_element_get_request_pad(comp, "sink_0");
		GstPad *comp_sink_1_pad = gst_element_get_request_pad(comp, "sink_1");


		g_object_set(G_OBJECT(comp_sink_0_pad),
						"xpos", 0,
						"ypos", 0,
						"width", 480,
						"height", 360,
						"zorder", 1,
						"alpha", 1.0,
						NULL);

		/* Set properties for the compositor sink_1 */
		g_object_set(G_OBJECT(comp_sink_1_pad),
						"xpos", 0,
						"ypos", 0,
						"width", 480,
						"height", 360,
						"zorder", 2,
						"alpha", 0.5,
						NULL);


		/* Set properties for the source */
		g_object_set(G_OBJECT(video_test_src),
						"pattern", 0, // 0 is the default pattern (smpte)
						NULL);
		/* Add elements to the pipeline */
		gst_bin_add_many(GST_BIN(pipeline), comp, video_test_src, v4l2_src, nvvidconv1, nvvidconv2, nvvidconv3, video_convert, main_sink, vts_filter, nvv1_filter, nvv2_filter, nvc1_filter, vc_filter, NULL);

#if 0
		if (!gst_pad_set_caps(conv1_sink_pad, yuv_wh_caps_2)) {
				g_printerr("Failed to set caps videotest src pad.\n");
				return -1;
		}
#endif

#ifndef USE_PAD_LINK_METHOD
		if(!gst_element_link_many(video_test_src,vts_filter,nvvidconv1,nvv1_filter, NULL)){
				g_printerr("2Elements could not be linked. \n");
				gst_object_unref(pipeline);
				return -1 ;	
		}
		if(!gst_element_link_many(v4l2_src,video_convert,vc_filter, nvvidconv2,nvv2_filter, NULL)){
				g_printerr("3Elements could not be linked. \n");
				gst_object_unref(pipeline);
				return -1 ;	
		}
		
		if(!gst_element_link_many(comp,nvc1_filter,nvvidconv3,main_sink, NULL)){
				g_printerr("1Elements could not be linked. \n");
				gst_object_unref(pipeline);
				return -1 ;	
		}
		if (gst_pad_link( nvv1_filter_src_pad, comp_sink_0_pad) != GST_PAD_LINK_OK) {
				g_printerr("44Failed to link sink_0 pad of comp to conv1.\n");
				return -1;
		}

		if (gst_pad_link( nvv2_filter_src_pad, comp_sink_1_pad) != GST_PAD_LINK_OK) {
				g_printerr("33Failed to link sink_0 pad of comp to conv1.\n");
				return -1;
		}

#endif	

#ifdef USE_PAD_LINK_METHOD
		/* videotestsrc pipeline */
		if (gst_pad_link( videotestsrc_src_pad, conv1_sink_pad) != GST_PAD_LINK_OK) {
				g_printerr("Failed to link conv1_sink_pad to coi@mp_src0pad\n");
				return -1;
		}
		if (gst_pad_link( conv1_src_pad, comp_sink_0_pad) != GST_PAD_LINK_OK) {
				g_printerr("Failed to link conv1_sink_pad to comp_src0pad\n");
				return -1;
		}
		//		gst_object_unref(conv1_src_pad);

		/* Set the caps on conv1_pad and comp_src0pad*/
#ifdef TO_REINSTATE_aFTER_VERIFICATION
		if (!gst_pad_set_caps(conv1_src_pad, rgba_nvmm_caps_1)) {
				g_printerr("Failed to set caps on conv1 pad.\n");
				return -1;
		}
		if (!gst_pad_set_caps(comp_sink_0_pad, rgba_nvmm_caps_1)) {
				g_printerr("Failed to set caps on sink-0comp pad.\n");
				return -1;
		}
#endif

		//		gst_object_unref(comp_sink_0_pad);
		//2nd pipeline 
		if (gst_pad_link( v4l2src_src_pad, video_convert_sink_pad) != GST_PAD_LINK_OK) {
				g_printerr("2Failed to link sink_0 pad of comp to conv1.\n");
				return -1;
		}

		if (gst_pad_link( video_convert_src_pad, conv2_sink_pad) != GST_PAD_LINK_OK) {
				g_printerr("1Failed to link sink_0 pad of comp to conv1.\n");
				return -1;
		}


		if (gst_pad_link( conv2_src_pad, comp_sink_1_pad) != GST_PAD_LINK_OK) {
				g_printerr("33Failed to link sink_0 pad of comp to conv1.\n");
				return -1;
		}
#if 0
		/* Set the caps on conv1_pad and comp_src0pad*/
		if (!gst_pad_set_caps(conv2_src_pad, rgba_wh_caps_4)) {
				g_printerr("Failed to set caps on conv1 pad.\n");
				return -1;
		}
		if (!gst_pad_set_caps(comp_sink_1_pad, rgba_wh_caps_4)) {
				g_printerr("Failed to set caps on conv1 pad.\n");
				return -1;
		}
#endif	
		//		gst_object_unref(comp_sink_1_pad);
		//main pipeline
		//here we join the two sources to compositor.

		if (gst_pad_link( comp_src_0_pad, conv3_sink_pad) != GST_PAD_LINK_OK) {
				g_printerr("55Failed to link sink_0 pad of comp to conv1.\n");
				return -1;
		}

		if (gst_pad_link( conv3_src_pad, main_sink_sink_pad) != GST_PAD_LINK_OK) {
				g_printerr("Failed to link sink_0 pad of comp to conv1.\n");
				return -1;
		}
#endif
		/* Set the pipeline state to playing */
		ret = gst_element_set_state(pipeline, GST_STATE_PLAYING);
		if (ret == GST_STATE_CHANGE_FAILURE) {
				g_printerr ("Unable to set the pipeline to the playing state.\n");
				gst_object_unref (pipeline);
				return -1;
		}
		/* Wait until error or EOS */
		bus = gst_element_get_bus(pipeline);
		msg = gst_bus_timed_pop_filtered(bus, GST_CLOCK_TIME_NONE, GST_MESSAGE_ERROR | GST_MESSAGE_EOS);

		/* Parse message */
		if (msg != NULL) {
				GError *err;
				gchar *debug_info;

				switch (GST_MESSAGE_TYPE (msg)) {
						case GST_MESSAGE_ERROR:
								gst_message_parse_error (msg, &err, &debug_info);
								g_printerr ("Error received from element %s: %s\n",
												GST_OBJECT_NAME (msg->src), err->message);
								g_printerr ("Debugging information: %s\n",
												debug_info ? debug_info : "none");
								g_clear_error (&err);
								g_free (debug_info);
								break;
						case GST_MESSAGE_EOS:
								g_print ("End-Of-Stream reached.\n");
								break;
						default:
								/* We should not reach here because we only asked for ERRORs and EOS */
								g_printerr ("Unexpected message received.\n");
								break;
				}
				gst_message_unref (msg);
		}
		/* Free resources */
		//		gst_object_unref(conv2_sink_pad);

#if 0
		gst_object_unref(comp_src_0_pad);
		gst_object_unref(conv1_sink_pad);
		/* Release elements */
		gst_object_unref(main_sink);
		gst_object_unref(video_convert);
		gst_object_unref(nvvidconv3);
		gst_object_unref(nvvidconv2);
		gst_object_unref(nvvidconv1);
		gst_object_unref(v4l2_src);
		gst_object_unref(video_test_src);
		gst_object_unref(comp);
		gst_object_unref(pipeline);

#endif
		gst_object_unref(bus);
		gst_element_set_state(pipeline, GST_STATE_NULL);
		return 0;
}