# Elements

## Creating a GstElement

A `GstElement` object is created from a factory. To create an element, you have to get access to a `GstElementFactory` object using a unique factory name.

The following code example is used to get a factory that can be used to create the 'mad' element, an mp3 decoder.

     GstElementFactory *factory;

     factory = gst_element_factory_find ("mad");

Once you have the handle to the element factory, you can create a real element with the following code fragment:

     GstElement *element;

     element = gst_element_factory_create (factory, "decoder");

`gst_element_factory_create` will use the element factory to create an element with the given name. The name of the element is something you can use later on to look up the element in a bin, for example. You can pass NULL as the name argument to get a unique, default name.

A simple shortcut exists for creating an element from a factory. The following example creates an element named "decoder" from the element factory named "mad". This convenience function is most widely used to create an element.

     GstElement *element;

     element = gst_element_factory_make ("mad", "decoder");

When you don't need the element anymore, you need to unref it, as shown in the following example.

     GstElement *element;

      ...
     gst_element_unref (element);

## GstElement properties

A `GstElement` can have several properties which are implemented using standard `GObject` properties. The usual `GObject` methods to query, set and get property values and `GParamSpecs` are therefore supported.

Every `GstElement` inherits at least one property of its parent `GstObject`: the "name" property. This is the name you provide to the functions `gst_element_factory_make` or `gst_element_factory_create`. You can get and set this property using the functions `gst_object_set_name` and `gst_object_get_name` or use the `GObject` property mechanism as shown below.

     GstElement *element;
     GValue value = { 0, }; /* initialize the GValue for g_object_get() */

     element = gst_element_factory_make ("mad", "decoder");
     g_object_set (G_OBJECT (element), "name", "mydecoder", NULL);
     ...

     g_value_init (&value, G_TYPE_STRING);
     g_object_get_property (G_OBJECT (element), "name", &value);
     ...

Most plugins provide additional properties to provide more information about their configuration or to configure the element. `gst-inspect` is a useful tool to query the properties of a particular element, it will also use property introspection to give a short explanation about the function of the property and about the parameter types and ranges it supports.

For more information about `GObject` properties we recommend you read the GObject manual and an introduction to The Glib Object system.

## GstElement signals

A `GstElement` also provides various `GObject` signals that can be used as a flexible callback mechanism.

## More about GstElementFactory

We talk some more about the GstElementFactory object.

### Getting information about an element using the factory details

### Finding out what pads an element can contain

### Different ways of querying the factories