gst_task_set_lock (task, GST_PAD_GET_STREAM_LOCK (pad));
gst_task_set_enter_callback (task, pad_enter_thread, pad, NULL);
gst_task_set_leave_callback (task, pad_leave_thread, pad, NULL);
gst_task_set_lock (task, GST_PAD_GET_STREAM_LOCK (pad));
gst_task_set_enter_callback (task, pad_enter_thread, pad, NULL);
gst_task_set_leave_callback (task, pad_leave_thread, pad, NULL);