The MCI_OVLY_RECT_PARMS structure contains positioning information for the MCI_PUT and MCI_WHERE commands for video-overlay devices.
typedef struct {
    DWORD dwCallback;  
    RECT  rc;          
} MCI_OVLY_RECT_PARMS;
 When assigning data to the members of this structure, set the corresponding flags in the fdwCommand parameter of the mciSendCommand function to validate the members.
  Windows NT: Requires version 3.1 or later.
  Windows: Requires Windows 95 or later.
  Windows CE: Unsupported.
  Header: Declared in mmsystem.h.
MCI Overview, MCI Structures, MCI_PUT, MCI_WHERE, mciSendCommand, RECT