gst trick player

trick.c

#include <stdio.h>
#include <stdlib.h>
#include <gst/gst.h>

typedef struct _AppElements {
	GMainLoop *loop;
	GstElement *pipeline;
	GstElement *source;
	GstElement *demuxer;
	GstElement *convert;
	GstElement *sink;
} AppElements;

gboolean loop = FALSE;

static gboolean
handle_keyboard (GIOChannel *source, GIOCondition cond, AppElements *app) {
	gchar *str = NULL;

	if (g_io_channel_read_line (source, &str, NULL, NULL, NULL) != G_IO_STATUS_NORMAL) {
		return TRUE;
	}

	switch (g_ascii_tolower (str[0])) {
		case 'q':
			g_main_loop_quit (app->loop);
			break;
		case 'l':
			g_print ("Looping activated\n");
			loop = TRUE;
			break;
		default:
			break;
		}

	g_free (str);

	return TRUE;
}

GstElement *
gst_element_factory_make_or_error (const gchar *factoryname, const gchar *name) {
	GstElement *element;
	element = gst_element_factory_make (factoryname, name);
	if (!element) {
		g_printerr ("Element \'%s\' could not be created. Exiting...\n", factoryname);
		exit(1);
	}

	return element;
}

static gboolean
bus_callback (GstBus *bus, GstMessage *msg, gpointer data) {
	AppElements *app = (AppElements*) data;

	switch (GST_MESSAGE_TYPE(msg))
	{
		case GST_MESSAGE_EOS: {
			/* end of stream received */
			g_print("Received End-of-Stream Signal\n");
			if (loop) {
				g_print ("Performing loop\n");
				if (!gst_element_seek (app->pipeline, 1.0, GST_FORMAT_TIME, GST_SEEK_FLAG_FLUSH,
												 GST_SEEK_TYPE_SET, 2 * GST_SECOND,
												 GST_SEEK_TYPE_SET, 5 *GST_SECOND)) {
					g_print ("Seek failed!\n");
				}
			}
			else {
				g_main_loop_quit (app->loop);
			}
			break;
		}
		case GST_MESSAGE_SEGMENT_DONE: {
			g_print ("Received SEGMENT DONE Message\n");
			break;
		}
		case GST_MESSAGE_ERROR: {
			gchar *debug;
			GError *error;

			gst_message_parse_error (msg, &error, &debug);
			g_free (debug);

			g_printerr ("Error: %s\n", error->message);
			g_error_free (error);

			g_main_loop_quit (app->loop);
			break;
		}
		default:
			/* unhandled message */
			break;
	}

	return TRUE;
}

/* This function will be called by the pad-added signal */
static void
pad_added_handler (GstElement *src, GstPad *new_pad, AppElements *data) {
	GstPad *sink_pad = gst_element_get_static_pad (data->convert, "sink");
	GstPadLinkReturn ret;
	GstCaps *new_pad_caps = NULL;
	GstStructure *new_pad_struct = NULL;
	const gchar *new_pad_type = NULL;

	g_print ("Received new pad '%s' from '%s':\n", GST_PAD_NAME (new_pad), GST_ELEMENT_NAME (src));

	/* If our converter is already linked, we have nothing to do here */
	if (gst_pad_is_linked (sink_pad)) {
		g_print ("  We are already linked. Ignoring.\n");
		goto exit;
	}

	/* Check the new pad's type */
	new_pad_caps = gst_pad_query_caps (new_pad, NULL);
	new_pad_struct = gst_caps_get_structure (new_pad_caps, 0);
	new_pad_type = gst_structure_get_name (new_pad_struct);
	if (!g_str_has_prefix (new_pad_type, "video/x-raw")) {
		g_print ("  It has type '%s' which is not raw video. Ignoring.\n", new_pad_type);
		goto exit;
	}

	/* Attempt the link */
	ret = gst_pad_link (new_pad, sink_pad);
	if (GST_PAD_LINK_FAILED (ret)) {
		g_print ("  Type is '%s' but link failed.\n", new_pad_type);
	} else {
		g_print ("  Link succeeded (type '%s').\n", new_pad_type);
	}

exit:
	/* Unreference the new pad's caps, if we got them */
	if (new_pad_caps != NULL)
		gst_caps_unref (new_pad_caps);

	/* Unreference the sink pad */
	gst_object_unref (sink_pad);
}

int
main(int argc, gchar *argv[]) {
	AppElements app;
	GstBus *bus;
	GIOChannel *io_stdin;
	guint bus_watch_id;

	gst_init (&argc, &argv);

	if (argc != 2) {
		g_print("Usage: %s FILE\n", argv[0]);
		return -1;
	}

	app.loop = g_main_loop_new(NULL, FALSE);

	app.pipeline = gst_pipeline_new ("autovideo-pipe");
	if (!app.pipeline) {
		g_printerr ("Pipeline could not be created. Exiting.\n");
		return -1;
	}

	app.source = gst_element_factory_make_or_error ("filesrc", "filesrc");
	app.demuxer = gst_element_factory_make_or_error ("decodebin", "decodebin");
	app.convert = gst_element_factory_make_or_error ("videoconvert", "convert");
	app.sink = gst_element_factory_make_or_error ("autovideosink", "sink");

	g_object_set (app.source, "location", argv[1], NULL);

	/* Connect the Pipeline Bus with out callback */
	bus = gst_pipeline_get_bus (GST_PIPELINE (app.pipeline));
	bus_watch_id = gst_bus_add_watch (bus, bus_callback, &app);
	gst_object_unref (bus);

	gst_bin_add_many (GST_BIN (app.pipeline), app.source, app.demuxer, app.convert, app.sink, NULL);

	gst_element_link (app.source, app.demuxer);
	gst_element_link (app.convert, app.sink);


	// TODO connect the singals
	g_signal_connect (app.demuxer, "pad-added", G_CALLBACK (pad_added_handler), &app);

	/* Setting up the Pipeline using Segments */
	gst_element_set_state (app.pipeline, GST_STATE_PAUSED);
	io_stdin = g_io_channel_unix_new (fileno (stdin));

	g_io_add_watch (io_stdin, G_IO_IN, (GIOFunc) handle_keyboard, &app);

	/* run the pipeline */
	g_print ("Running...\n");
	gst_element_set_state (app.pipeline, GST_STATE_PLAYING);

	g_main_loop_run (app.loop);

	/* cleanup */
	g_print ("STOPPING Pipeline\n");
	gst_element_set_state (app.pipeline, GST_STATE_NULL);

	g_print ("DELETING Pipeline\n");
	gst_object_unref (GST_OBJECT (app.pipeline));

	g_print ("DELETING Bus\n");
	g_source_remove (bus_watch_id);

	return 0;
}