cbasefilter-getsyncsource.md

description	ms.assetid	title	ms.topic	ms.date	topic_type	api_name	api_type	api_location	ms.custom
The GetSyncSource method retrieves the reference clock that the filter is using. This method implements the IMediaFilter::GetSyncSource method.	b8c95838-bd6e-41c5-b3ab-71ebb33136f0	CBaseFilter.GetSyncSource method (Amfilter.h)	reference	4/26/2023	APIRef kbSyntax	CBaseFilter.GetSyncSource	COM	Strmbase.lib Strmbase.dll Strmbasd.lib Strmbasd.dll	UpdateFrequency5

CBaseFilter.GetSyncSource method

[The feature associated with this page, DirectShow, is a legacy feature. It has been superseded by MediaPlayer, IMFMediaEngine, and Audio/Video Capture in Media Foundation. Those features have been optimized for Windows 10 and Windows 11. Microsoft strongly recommends that new code use MediaPlayer, IMFMediaEngine and Audio/Video Capture in Media Foundation instead of DirectShow, when possible. Microsoft suggests that existing code that uses the legacy APIs be rewritten to use the new APIs if possible.]

The GetSyncSource method retrieves the reference clock that the filter is using. This method implements the IMediaFilter::GetSyncSource method.

Syntax

HRESULT GetSyncSource(
   IReferenceClock **pClock
);

Parameters

pClock

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

Return value

Returns S_OK or E_POINTER.

Remarks

If the filter is not using a reference clock, *pClock is set to 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.

Requirements

Requirement	Value
Header	Amfilter.h (include Streams.h)
Library	Strmbase.lib (retail builds); Strmbasd.lib (debug builds)

See also

CBaseFilter Class