+void ev_metadata_manager_set_double (const gchar *uri,
+ const gchar *key,
+ double value);
+void ev_metadata_manager_set_string (const gchar *uri,
+ const gchar *key,
+ const gchar *value);
+void ev_metadata_manager_set_boolean (const gchar *uri,
+ const gchar *key,
+ gboolean value);