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IWMReader::GetOutputCount 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 It has been superseded by Source Reader and Sink Writer.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 GetOutputCount method retrieves the number of uncompressed media streams that will be delivered for the file loaded in the reader.

Syntax

HRESULT GetOutputCount(
  [out] DWORD *pcOutputs
);

Parameters

[out] pcOutputs

Pointer to a count of outputs.

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_POINTER
The pcOutputs parameter is NULL.
E_UNEXPECTED
The method failed for an unspecified reason.

Remarks

A file with mutually exclusive streams contains several streams that are delivered to the same output. But only one of those streams can be delivered at a time during playback. When reading a file, you can identify its outputs by looping through the outputs and getting the media properties of each by calling IWMReader::GetOutputProps.

This method is synchronous and does not result in any messages being sent to the status callback.

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

IWMReader Interface

IWMReader::GetOutputProps