+ * #GstContext is a container object used to store contexts like a device
+ * context, a display server connection and similar concepts that should
+ * be shared between multiple elements.
+ *
+ * Applications can set a context on a complete pipeline by using
+ * gst_element_set_context(), which will then be propagated to all
+ * child elements. Elements can handle these in #GstElementClass.set_context()
+ * and merge them with the context information they already have.
+ *
+ * When an element needs a context it will do the following actions in this
+ * order until one step succeeds:
+ * 1. Check if the element already has a context
+ * 2. Query downstream with GST_QUERY_CONTEXT for the context
+ * 3. Query upstream with GST_QUERY_CONTEXT for the context
+ * 4. Post a GST_MESSAGE_NEED_CONTEXT message on the bus with the required
+ * context types and afterwards check if a usable context was set now
+ * 5. Create a context by itself and post a GST_MESSAGE_HAVE_CONTEXT message
+ * on the bus.
+ *
+ * Bins will catch GST_MESSAGE_NEED_CONTEXT messages and will set any previously
+ * known context on the element that asks for it if possible. Otherwise the
+ * application should provide one if it can.
+ *
+ * #GstContext<!-- -->s can be persistent.
+ * A persistent #GstContext is kept in elements when they reach
+ * %GST_STATE_NULL, non-persistent ones will be removed.
+ * Also, a non-persistent context won't override a previous persistent
+ * context set to an element.
+ *
+ * Since: 1.2