IWMReaderAdvanced::SetUserProvidedClock method (wmsdkidl.h)

[The feature associated with this page, Windows Media Format 11 SDK, is a legacy feature. It has been superseded by Source Reader and Sink Writer. Source Reader and Sink Writer have been optimized for Windows 10 and Windows 11. Microsoft strongly recommends that new code use Source Reader and Sink Writer instead of Windows Media Format 11 SDK, when possible. Microsoft suggests that existing code that uses the legacy APIs be rewritten to use the new APIs if possible.]

The SetUserProvidedClock method specifies whether a clock provided by the application is to be used.

Syntax

HRESULT SetUserProvidedClock(
  [in] BOOL fUserClock
);

Parameters

[in] fUserClock

Boolean value that is True if an application-provided clock is to be used.

Return value

The method returns an HRESULT. Possible values include, but are not limited to, those in the following table.

Return code Description
S_OK
The method succeeded.
NS_E_INVALID_REQUEST
The reader is not properly configured to handle this request.
E_OUTOFMEMORY
The method was unable to allocate memory.
E_FAIL
Unable to set an internal event.

Remarks

In some cases, an application built on this SDK requires the clock to be driven by the application rather than by real time. This is true, for example, if the application reads from a file at a rate faster than it takes to play the file. User-provided clocks are only supported when the source file is a local file.

This method can fail if the current source does not support user-provided clocks. To drive a clock, an application must call DeliverTime, and then wait for IWMReaderCallbackAdvanced::OnTime to reach the time specified.

Requirements

Requirement Value
Minimum supported client Windows 2000 Professional [desktop apps only],Windows Media Format 7 SDK, or later versions of the SDK
Minimum supported server Windows 2000 Server [desktop apps only]
Target Platform Windows
Header wmsdkidl.h (include Wmsdk.h)
Library Wmvcore.lib; WMStubDRM.lib (if you use DRM)

See also

IWMReaderAdvanced Interface

IWMReaderAdvanced::GetUserProvidedClock