IMFSourceReader::GetPresentationAttribute method (mfreadwrite.h)

Gets an attribute from the underlying media source.

Syntax

HRESULT GetPresentationAttribute(
  [in]  DWORD       dwStreamIndex,
  [in]  REFGUID     guidAttribute,
  [out] PROPVARIANT *pvarAttribute
);

Parameters

[in] dwStreamIndex

The stream or object to query. The value can be any of the following.

[in] guidAttribute

A GUID that identifies the attribute to retrieve. If the dwStreamIndex parameter equals MF_SOURCE_READER_MEDIASOURCE, guidAttribute can specify one of the following:

• A presentation descriptor attribute. For a list of values, see Presentation Descriptor Attributes.
• MF_SOURCE_READER_MEDIASOURCE_CHARACTERISTICS. Use this value to get characteristics flags from the media source.

[out] pvarAttribute

A pointer to a PROPVARIANT that receives the value of the attribute. Call the PropVariantClear function to free the PROPVARIANT.

Return value

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

Remarks

This interface is available on Windows Vista if Platform Update Supplement for Windows Vista is installed.

Requirements

See also

IMFSourceReader

Media Foundation Attributes

Source Reader