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CVideoTransformFilter.AlterQuality method

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[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 It has been superseded by MediaPlayer, IMFMediaEngine, and Audio/Video Capture in Media Foundation.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 AlterQuality method notifies the filter that a quality change is requested. This method overrides the CTransformFilter::AlterQuality method.

Syntax

virtual HRESULT AlterQuality(
   Quality q
);

Parameters

q

Quality structure that contains the quality control message.

Return value

Returns E_FAIL.

Remarks

This method is called when the output pin receives a quality message (through the IQualityControl::Notify method).

The lateness value from q is stored in the m_itrLate member variable. The return value of E_FAIL indicates that the renderer should catch up by dropping frames, although the CVideoTransformFilter class will also drop frames under the right conditions.

Requirements

Requirement Value
Header
Vtrans.h (include Streams.h)
Library
Strmbase.lib (retail builds);
Strmbasd.lib (debug builds)

See also

CVideoTransformFilter Class

CVideoTransformFilter::ShouldSkipFrame