Microsoft DirectX 9.0


The GetSyncSource method retrieves the current reference clock.


HRESULT GetSyncSource(
  IReferenceClock **pClock



[out] Address of a variable that receives a pointer to the clock's IReferenceClock interface.

Return Value

Returns an HRESULT value. Possible values include those shown in the following table.

Value Description
S_OK Success
E_POINTER NULL pointer argument


This method returns the same reference clock as the last call to IMediaFilter::SetSyncSource. If there is no reference clock, pClock receives the value NULL. When the method returns, if *pClock is non-NULL, the IReferenceClock interface has an outstanding reference count. Be sure to release it when you are done.

You can also call this method on the Filter Graph Manager to determine the current reference clock.

See Also