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IVMRImagePresenter::PresentImage

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Microsoft DirectShow 9.0

IVMRImagePresenter::PresentImage

The PresentImage method is called at precisely the moment this video frame should be presented.

Syntax

  HRESULT PresentImage(
  DWORD_PTR  dwUserID,
  VMRPRESENTATIONINFO*  lpPresInfo
);

Parameters

dwUserID

[in]  An application-defined DWORD_PTR that uniquely identifies this instance of the VMR in scenarios when multiple instances of the VMR are being used with a single instance of an Allocator-Presenter. See Remarks

lpPresInfo

[in]  Specifies the VMRPRESENTATIONINFO structure.

Return Values

If the method succeeds, it returns S_OK. If it fails, it returns an error code.

Remarks

PresentImage can be called when the filter is in either a running or a paused state. StartPresenting and StopPresenting can be called only in a running state. Therefore, if the graph is paused before it is run, PresentImage will be called before StartPresenting.

Applications can create custom blending effects by using a single instance of an Allocator-Presenter with multiple instances of the VMR either in a single filter graph or in multiple filter graphs. Using the allocator presenter in this way enables applications to blend streams from different filter graphs, or blend different streams within the same filter graph. If you are using a single instance of the VMR, set this value to zero.

Requirements

Header: Declared in Strmif.h; include Dshow.h.

Library: Use Strmiids.lib.

See Also