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IAMOpenProgress Interface

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Microsoft DirectShow 9.0

IAMOpenProgress Interface

The IAMOpenProgress interface reports the progress of a file-open operation and enables the application to cancel the operation.

Filters that open files over a network can expose this interface. An application can use it to query the progress of the download, or to cancel the download. If the network is not responsive, a method such as IGraphBuilder::RenderFile might block for an indefinite period. To prevent your application from blocking, create a worker thread that uses IAMOpenProgress to monitor the progress. The worker thread can cancel the operation if a predefined timeout occurs, or in response to a command from the user.

The File Source (URL) filter supports this interface.

In addition to the methods inherited from IUnknown, the IAMOpenProgress interface exposes the following methods.

Method Description
QueryProgress Retrieves the progress of the file-open operation.
AbortOperation Cancels the file-open operation.

Requirements

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

Library: Use Strmiids.lib.