- static void gstCBpadAdded(GstElement *decodebin, GstPad *pad, gpointer data); /* for mpegdemux */
- static void gstCBfilterPadAdded(GstElement *filter, GstPad *pad, gpointer user_data); /* for id3demux */
- static void gstCBnewPad(GstElement *decodebin, GstPad *pad, gboolean last, gpointer data); /* for decodebin */
- static void gstCBunknownType(GstElement *decodebin, GstPad *pad, GstCaps *l, gpointer data);