IMediaSeeking::GetPreroll method (strmif.h)

[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 It has been superseded by MediaPlayer, IMFMediaEngine, and Audio/Video Capture in Media Foundation.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 GetPreroll method retrieves the amount of data that will be queued before the start position.

Syntax

HRESULT GetPreroll(
  [out] LONGLONG *pllPreroll
);

Parameters

[out] pllPreroll

Pointer to a variable that receives the preroll time, in units of the current time format.

Return value

Returns an HRESULT value. Possible values include the following.

Remarks

The preroll is the time prior to the start position at which nonrandom access devices, such as tape players, should start rolling.

The returned value is expressed in the current time format. The default time format is REFERENCE_TIME units (100 nanoseconds). To change time formats, use the IMediaSeeking::SetTimeFormat method.

Requirements

See also

Error and Success Codes

IMediaSeeking Interface