format  void STM_CloseGrp (StmGrpHn grp)
 Input  grp: Stream group handle
 Output  None
 Function value  None
 Function  Closes the stream group.
 Remarks  All streams belonging to a stream group are closed. 

  format  Sint32 STM_GetStmNum (StmGrpHn grp)
 Input  grp: Stream group handle
 Output  None
 Function value  The number of streams belonging to the stream group.
 Function  Gets the number of streams belonging to the specified stream group. 

  format  StmHn STM_GetStmHndl (StmGrpHn grp, Sint32 nstm)
 Input  grp: Stream group handle
:  nstm: Playback order number (0 ≤ nstm  Output  None
 Function value  Stream handle of the specified playback order number.
  NULL if there is no corresponding stream.
 Function  Gets the handle of a stream belonging to the specified stream group.
 Remarks  The playback order when the following four streams belong to the same stream group:
  is in the order of streams A, B, C, and D.