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IWMSyncReader::SetReadStreamSamples 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 It has been superseded by Source Reader and Sink Writer.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 SetReadStreamSamples method specifies whether samples from a stream will be delivered compressed or uncompressed.

Syntax

HRESULT SetReadStreamSamples(
  [in] WORD wStreamNum,
  [in] BOOL fCompressed
);

Parameters

[in] wStreamNum

WORD containing the stream number.

[in] fCompressed

Boolean value that is True if samples will be compressed.

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_UNEXPECTED
No file is open in the synchronous reader.
NS_E_PROTECTED_CONTENT
The stream is protected and not configured to deliver compressed samples.
E_INVALIDARG
wStreamNum specifies an invalid stream number.

Remarks

You can call SetReadStreamSamples at any time after a file has been loaded into the synchronous reader. You can continue making calls as needed during playback.

Requirements

Requirement Value
Minimum supported client Windows 2000 Professional [desktop apps only],Windows Media Format 9 Series 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

IWMSyncReader Interface

IWMSyncReader::GetReadStreamSamples