ElementFactory

Object Hierarchy:

Description:

  #include <gst/gst.h>

  GstElement *src;
  GstElementFactory *srcfactory;

  gst_init (&argc, &argv);

  srcfactory = gst_element_factory_find ("filesrc");
  g_return_if_fail (srcfactory != NULL);
  src = gst_element_factory_create (srcfactory, "src");
  g_return_if_fail (src != NULL);
  ...

// See http://docs.gstreamer.com/x/ZgAF
// for a detailed description

public static int main (string[] args) {

	// Initialize GStreamer:
	Gst.init (ref args);

	// Create the elements:
	Gst.Element source = Gst.ElementFactory.make ("videotestsrc", "source");
	Gst.Element sink = Gst.ElementFactory.make ("autovideosink", "sink");

	// Create the empty pipeline:
	Gst.Pipeline pipeline = new Gst.Pipeline ("test-pipeline");

	if (source == null || sink == null || pipeline == null) {
		stderr.puts ("Not all elements could be created.\n");
		return -1;
	}

	// Build the pipeline:
	pipeline.add_many (source, sink);

	if (source.link (sink) != true) {
		stderr.puts ("Elements could not be linked.\n");
		return -1;
	}

	// Modify the source's properties:
	source.set ("pattern", 0);

	// Start playing:
	Gst.StateChangeReturn ret = pipeline.set_state (Gst.State.PLAYING);
	if (ret == Gst.StateChangeReturn.FAILURE) {
		stderr.puts ("Unable to set the pipeline to the playing state.\n");
		return -1;
	}

	// Wait until error or EOS:
	Gst.Bus bus = pipeline.get_bus ();
	Gst.Message msg = bus.timed_pop_filtered (Gst.CLOCK_TIME_NONE, Gst.MessageType.ERROR | Gst.MessageType.EOS);


	// Parse message:
	if (msg != null) {
		switch (msg.type) {
		case Gst.MessageType.ERROR:
			GLib.Error err;
			string debug_info;

			msg.parse_error (out err, out debug_info);
			stderr.printf ("Error received from element %s: %s\n", msg.src.name, err.message);
			stderr.printf ("Debugging information: %s\n", (debug_info != null)? debug_info : "none");
			break;

		case Gst.MessageType.EOS:
			print ("End-Of-Stream reached.\n");
			break;

		default:
			// We should not reach here because we only asked for ERRORs and EOS:
			assert_not_reached ();
		}
	}


	// Free resources:
	pipeline.set_state (Gst.State.NULL);

	return 0;
}

valac --pkg gstreamer-1.0 concepts.vala

Content:

Static methods:

• public static ElementFactory? find (string name)
  Search for an element factory of the given name.
• public static List<ElementFactory> list_filter (List<ElementFactory> list, Caps caps, PadDirection direction, bool subsetonly)
  Filter out all the elementfactories in list that can handle caps in the given direction.
• public static List<ElementFactory> list_get_elements (ElementFactoryListType type, Rank minrank)
  Get a list of factories that match the given type.
• public static Element? make (string factoryname, string? name = null)
  Create a new element of the type defined by the given element factory.
• public static Element? make_full (string factoryname, string? first, ...)
  Create a new element of the type defined by the given element factory.
• public static Element? make_valist (string factoryname, string? first, va_list? properties)
  Create a new element of the type defined by the given element factory.
• public static Element? make_with_properties (string factoryname, string[]? names, Value[]? values)
  Create a new element of the type defined by the given elementfactory.

Creation methods:

• protected ElementFactory ()

Methods:

• public bool can_sink_all_caps (Caps caps)
  Checks if the factory can sink all possible capabilities.
• public bool can_sink_any_caps (Caps caps)
  Checks if the factory can sink any possible capability.
• public bool can_src_all_caps (Caps caps)
  Checks if the factory can src all possible capabilities.
• public bool can_src_any_caps (Caps caps)
  Checks if the factory can src any possible capability.
• public Element? create (string? name)
  Create a new element of the type defined by the given elementfactory.
• public Element? create_full (string? first, ...)
  Create a new element of the type defined by the given elementfactory.
• public Element? create_valist (string? first, va_list? properties)
  Create a new element of the type defined by the given elementfactory.
• public Element? create_with_properties (string[]? names, Value[]? values)
  Create a new element of the type defined by the given elementfactory.
• public Type get_element_type ()
  Get the Type for elements managed by this factory.
• public unowned string? get_metadata (string key)
  Get the metadata on this with key .
• public string[]? get_metadata_keys ()
  Get the available keys for the metadata on this .
• public uint get_num_pad_templates ()
  Gets the number of pad_templates in this factory.
• public bool get_skip_documentation ()
  Queries whether registered element managed by this needs to be excluded from documentation system or not.
• public unowned List<StaticPadTemplate?> get_static_pad_templates ()
  Gets the List of StaticPadTemplate for this factory.
• public unowned string[] get_uri_protocols ()
  Gets a null-terminated array of protocols this element supports or null if no protocols are supported.
• public URIType get_uri_type ()
  Gets the type of URIs the element supports or UNKNOWN if none.
• public bool has_interface (string interfacename)
  Check if this implements the interface with name interfacename.
• public bool list_is_type (ElementFactoryListType type)
  Check if this is of the given types.

Inherited Members: