IMFPMediaPlayer::GetPosition method (mfplay.h)

Artigo
12/05/2018

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 It has been superseded by MediaPlayer and IMFMediaEngine.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

Gets the current playback position.

Syntax

HRESULT GetPosition(
  [in]  REFGUID     guidPositionType,
  [out] PROPVARIANT *pvPositionValue
);

Parameters

[in] guidPositionType

Specifies the unit of time for the playback position. The following value is defined.

Value	Meaning
MFP_POSITIONTYPE_100NS	100-nanosecond units. The value returned in pvPositionValue is a LARGE_INTEGER. Variant type (vt): VT_I8 Variant member: hVal

Value

Meaning

MFP_POSITIONTYPE_100NS

100-nanosecond units.

The value returned in pvPositionValue is a LARGE_INTEGER.

Variant type (vt): VT_I8
Variant member: hVal

[out] pvPositionValue

Pointer to a PROPVARIANT that receives the playback position.

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.
E_INVALIDARG	Invalid argument.
MF_E_INVALIDREQUEST	No media item has been queued.
MF_E_SHUTDOWN	The object's Shutdown method was called.

Remarks

The playback position is calculated relative to the start time of the media item, which can be specified by calling IMFPMediaItem::SetStartStopPosition. For example, if you set the start time to 20 seconds and the source duration is 60 seconds, the range of values returned by GetPosition is 0–40 seconds.

Examples

The following code gets the current position, in 100-nanosecond units, as a LONGLONG value.

HRESULT GetPositionHNS(
    IMFPMediaPlayer *pPlayer, 
    LONGLONG *phnsPosition    // Receives the position in hns.
)
{
    HRESULT hr = S_OK;

    PROPVARIANT var;
    PropVariantInit(&var);

    *phnsPosition = 0;

    hr = pPlayer->GetPosition(MFP_POSITIONTYPE_100NS, &var);

    if (SUCCEEDED(hr))
    {
        *phnsPosition = var.hVal.QuadPart;
    }

    PropVariantClear(&var);
    return hr;
}

Requirements

Requirement	Value
Minimum supported client	Windows 7 [desktop apps only]
Minimum supported server	Windows Server 2008 R2 [desktop apps only]
Target Platform	Windows
Header	mfplay.h

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