IMFClockStateSink::OnClockSetRate Method

Called when the rate changes on the presentation clock.

Syntax

public:
HRESULT OnClockSetRate(
         MFTIME hnsSystemTime,
         float flRate
)  

Parameters

hnsSystemTime
Type: MFTIME 

The system time when the rate was set, in 100-nanosecond units.

flRate
Type: float 

The new rate, as a multiplier of the normal playback rate.

Return value

Type: HRESULT 

If this method succeeds, it returns S_OK. Otherwise, it returns an HRESULT error code.

Refer to Media Foundation return codes.

Remarks

When the presentation clock’s IMFRateControl::SetRate method is called, the clock notifies the presentation time source by calling the time source’s OnClockSetRate method. This call occurs synchronously within the SetRate method. If the time source returns an error from OnClockSetRate, the presentation clock’s SetRate method returns an error and the state change does not take place.

For any object that is not the presentation time source, the OnClockSetRate method is called asynchronously, after the state change is completed. In that case, the return value from this method is ignored.

Requirements

Header: Declared in mfidl.h.

Library: Use mfuuid.lib.