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IMediaObject::GetStreamCount method (mediaobj.h)

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 It has been superseded by MediaPlayer, IMFMediaEngine, and Audio/Video Capture in Media Foundation.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

The GetStreamCount method retrieves the number of input and output streams.

Syntax

HRESULT GetStreamCount(
  [out] DWORD *pcInputStreams,
  [out] DWORD *pcOutputStreams
);

Parameters

[out] pcInputStreams

Pointer to a variable that receives the number of input streams. Cannot be NULL.

[out] pcOutputStreams

Pointer to a variable that receives the number of output streams. Cannot be NULL.

Return value

Returns an HRESULT value. Possible values include those in the following table.

Return code Description
E_POINTER
NULL pointer argument
S_OK
Success

Remarks

The DMO might have zero input streams or zero output streams. The number of streams does not change; a DMO cannot dynamically add or remove streams.

Requirements

Requirement Value
Target Platform Windows
Header mediaobj.h (include Dmo.h)
Library Dmoguids.lib

See also

IMediaObject Interface