IEnumMediaTypes::Clone method (strmif.h)

Article
02/22/2024

[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 It has been superseded by MediaPlayer, IMFMediaEngine, and Audio/Video Capture in Media Foundation.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 Clone method makes a copy of the enumerator. The returned object starts with the same enumeration state as the original.

Syntax

HRESULT Clone(
  [out] IEnumMediaTypes **ppEnum
);

Parameters

[out] ppEnum

Receives a pointer to the IEnumMediaTypes interface of the new enumerator. The caller must release the interface.

Return value

Returns one of the following HRESULT values.

Return code	Description
S_OK	Success.
E_OUTOFMEMORY	Insufficient memory.
E_POINTER	NULL pointer argument.
VFW_E_ENUM_OUT_OF_SYNC	The pin's state has changed and is now inconsistent with the enumerator.

Remarks

If the set of media types changes, the enumerator is no longer consistent with the pin, and the method returns VFW_E_ENUM_OUT_OF_SYNC. Discard any data obtained from previous calls to the enumerator, because it might be invalid. Update the enumerator by calling the Reset method. You can then call the Clone method safely.

Requirements

Requirement	Value
Minimum supported client	Windows 2000 Professional [desktop apps only]
Minimum supported server	Windows 2000 Server [desktop apps only]
Target Platform	Windows
Header	strmif.h (include Dshow.h)
Library	Strmiids.lib