Important:
This is retired content. This content is outdated and is no longer being maintained. It is provided as a courtesy for individuals who are still using these technologies. This content may contain URLs that were valid when originally published, but now link to sites or pages that no longer exist.
A version of this page is also available for
4/8/2010

Multimedia components that provide time-based data expose the IMediaFilterinterface. This interface abstracts an object that processes time-based data streams and represents a multimedia device (possibly implemented in software). It controls the active or running state of the object and the synchronization of this state with other objects in the system.

This interface inherits the IPersistinterface.

When to Implement

Methods on this interface should be implemented as part of any filter. This is typically done by using the base class CBaseFilter, which implements IBaseFilterand IMediaFilter.

When to Use

Because the IMediaFilterinterface is inherited by the IBaseFilterinterface, which adds other necessary methods required to be exported by filters, this interface is not normally used directly by the filter graph manager or other filters. It can, however, be of use to plug-in distributors. For example, the filter graph manager internally exports IMediaFilter; its plug-in distributor exports IMediaControland calls the IMediaFiltermethods to implement its own methods.

Methods in Vtable Order

The following table shows the methods that appear in the Vtable beneath the standard COM methods inherited from IUnknown.

Method Description

Stop

Informs the filter to transition to the new (stopped) state.

Pause

Informs the filter to transition to the new (paused) state.

Run

Informs the filter to transition to the new (running) state.

GetState

Determines the state of the filter.

SetSyncSource

Identifies the reference clock to which the filter should synchronize activity.

GetSyncSource

Retrieves the current reference clock (or NULL if there is no clock). Passes a time value to synchronize independent streams.

Requirements

Windows Embedded CE Windows CE 2.12 and later
Windows Mobile Windows Mobile Version 5.0 and later
Note Microsoft DirectShow applications and DirectShow filters have different include file and Library requirements
For more information, see Setting Up the Build Environment

See Also