IQualityControl Interface

Microsoft DirectShow 9.0

IQualityControl Interface

The IQualityControl interface provides support for quality control. An object exposes this interface if it can generate or receive quality-control messages. This includes renderer filters (which typically generate quality control messages), pins (which receive them), and external quality managers (which also receive them).

A renderer filter generates a quality-control message by calling the IQualityControl::Notify method on the output pin of the upstream filter. The upstream filter either handles the message or passes it upstream.

An application can implement its own quality-control manager. Call IQualityControl::SetSink on the renderer to designate the quality-control manager as the recipient for quality-control messages. Calling this method overrides the default handling of quality-control messages.

However, most applications will not implement their own quality-control managers; and aside from this special case, applications typically do not use this interface. For more information, see Quality-Control Management

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

Method Description
Notify Notifies the recipient that a quality change is requested.
SetSink Sets the IQualityControl object that will receive quality messages.


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

Library: Use Strmiids.lib.