IAMOpenProgress interface (strmif.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 It has been superseded by MediaPlayer, IMFMediaEngine, and Audio/Video Capture in Media Foundation.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 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.

Inheritance

The IAMOpenProgress interface inherits from the IUnknown interface. IAMOpenProgress also has these types of members:

Methods

The IAMOpenProgress interface has these methods.

Requirements