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IWiaPreview::Clear method

Releases the unfiltered image cached by the IWiaPreview::GetNewPreview method. It also releases the image processing filter.

Syntax

void Clear();

Parameters

This method has no parameters.

Return value

This method does not return a value.

Remarks

On IWiaPreview::Clear the Windows Image Acquisition (WIA) 2.0 Preview Component releases all interface pointers that it stores. The WIA 2.0 Preview Component keeps references to pWiaItem2 and pWiaTransferCallback passed into IWiaPreview::GetNewPreview. To be precise, the WIA 2.0 Preview Component keeps a reference to pWiaItem2 and the driver's image processing filter, which in turn keeps a reference to pWiaTransferCallback. On IWiaPreview::Clear, the WIA 2.0 Preview Component also releases its reference to pWiaItem2 and to the image processing filter, which in turn releases its reference to pWiaTransferCallback. The WIA 2.0 Preview Component deletes the cached, unfiltered image that it stores internally.

Requirements

Requirement Value
Minimum supported client
Windows Vista [desktop apps only]
Minimum supported server
Windows Server 2008 [desktop apps only]
Header
Wia.h
IDL
Wia.idl