/usr/share/doc/gstreamer0.10-doc/manual/html/section-elements-properties.html

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>5.3. Using an element as a <CODE
CLASS="classname"
>GObject</CODE
></A
></H1
><P
> 
      A <A
HREF="http://gstreamer.freedesktop.org/data/doc/gstreamer/stable/gstreamer/html/GstElement.html"
TARGET="_top"
><CODE
CLASS="classname"
>GstElement</CODE
></A
>
      can have several properties which are implemented using standard
      <CODE
CLASS="classname"
>GObject</CODE
> properties. The usual
      <CODE
CLASS="classname"
>GObject</CODE
> methods to query, set and get
      property values and <CODE
CLASS="classname"
>GParamSpecs</CODE
> are
      therefore supported.
    </P
><P
> 
      Every <CODE
CLASS="classname"
>GstElement</CODE
> inherits at least one
      property from its parent <CODE
CLASS="classname"
>GstObject</CODE
>: the
      "name" property. This is the name you provide to the functions
      <CODE
CLASS="function"
>gst_element_factory_make ()</CODE
> or
      <CODE
CLASS="function"
>gst_element_factory_create ()</CODE
>. You can get
      and set this property using the functions 
      <CODE
CLASS="function"
>gst_object_set_name</CODE
> and
      <CODE
CLASS="function"
>gst_object_get_name</CODE
> or use the
      <CODE
CLASS="classname"
>GObject</CODE
> property mechanism as shown below.
    </P
><PRE
CLASS="programlisting"
>&#13;#include &#60;gst/gst.h&#62;

int
main (int   argc,
      char *argv[])
{
  GstElement *element;
  gchar *name;

  /* init GStreamer */
  gst_init (&#38;argc, &#38;argv);

  /* create element */
  element = gst_element_factory_make ("fakesrc", "source");

  /* get name */
  g_object_get (G_OBJECT (element), "name", &#38;name, NULL);
  g_print ("The name of the element is '%s'.\n", name);
  g_free (name);

  gst_object_unref (GST_OBJECT (element));

  return 0;
}
    </PRE
><P
>&#13;      Most plugins provide additional properties to provide more information
      about their configuration or to configure the element.
      <B
CLASS="command"
>gst-inspect</B
> 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. See
      <A
HREF="section-checklist-applications.html#section-applications-inspect"
>Section 21.4.2</A
>
      in the appendix for details about <B
CLASS="command"
>gst-inspect</B
>.
    </P
><P
>&#13;      For more information about <CODE
CLASS="classname"
>GObject</CODE
>
      properties we recommend you read the <A
HREF="http://developer.gnome.org/doc/API/2.0/gobject/index.html"
TARGET="_top"
>GObject manual</A
> and an introduction to <A
HREF="http://developer.gnome.org/doc/API/2.0/gobject/pr01.html"
TARGET="_top"
>&#13;	The Glib Object system</A
>.
    </P
><P
>&#13;      A <A
HREF="http://gstreamer.freedesktop.org/data/doc/gstreamer/stable/gstreamer/html/GstElementFactory.html"
TARGET="_top"
>&#13;      <CODE
CLASS="classname"
>GstElement</CODE
></A
> also provides various 
      <CODE
CLASS="classname"
>GObject</CODE
> signals that can be used as a flexible
      callback mechanism. Here, too, you can use <B
CLASS="command"
>gst-inspect</B
>
      to see which signals a specific element supports. Together, signals
      and properties are the most basic way in which elements and
      applications interact.
    </P
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gstreamer0.10-doc 0.10.36-1.5ubuntu1 / usr / share / doc / gstreamer0.10-doc / manual / html / section-elements-properties.html
