MFVP_MESSAGE_TYPE enumeration (evr.h)

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[The component described on this page, Enhanced Video Renderer, is a legacy feature. It has been superseded by the Simple Video Renderer (SVR) exposed through the MediaPlayer and IMFMediaEngine components. To play video content you should send data into one of these components and allow them to instantiate the new video renderer. These components have been optimized for Windows 10 and Windows 11. Microsoft strongly recommends that new code use MediaPlayer or the lower level IMFMediaEngine APIs to play video media in Windows instead of the EVR, when possible. Microsoft suggests that existing code that uses the legacy APIs be rewritten to use the new APIs if possible.]

Defines messages for an enhanced video renderer (EVR) presenter. This enumeration is used with the IMFVideoPresenter::ProcessMessage method.

Syntax

typedef enum MFVP_MESSAGE_TYPE {
  MFVP_MESSAGE_FLUSH = 0,
  MFVP_MESSAGE_INVALIDATEMEDIATYPE = 0x1,
  MFVP_MESSAGE_PROCESSINPUTNOTIFY = 0x2,
  MFVP_MESSAGE_BEGINSTREAMING = 0x3,
  MFVP_MESSAGE_ENDSTREAMING = 0x4,
  MFVP_MESSAGE_ENDOFSTREAM = 0x5,
  MFVP_MESSAGE_STEP = 0x6,
  MFVP_MESSAGE_CANCELSTEP = 0x7
} ;

Constants

 
MFVP_MESSAGE_FLUSH
Value: 0
The presenter should discard any pending samples. The ulParam parameter is not used and should be zero.
MFVP_MESSAGE_INVALIDATEMEDIATYPE
Value: 0x1
The mixer's output format has changed. The EVR will initiate format negotiation. The ulParam parameter is not used and should be zero.
MFVP_MESSAGE_PROCESSINPUTNOTIFY
Value: 0x2
One input stream on the mixer has received a new sample. The ulParam parameter is not used and should be zero.
MFVP_MESSAGE_BEGINSTREAMING
Value: 0x3
The EVR switched from stopped to paused. The presenter should allocate resources. The ulParam parameter is not used and should be zero.
MFVP_MESSAGE_ENDSTREAMING
Value: 0x4
The EVR switched from running or paused to stopped. The presenter should free resources. The ulParam parameter is not used and should be zero.
MFVP_MESSAGE_ENDOFSTREAM
Value: 0x5
All streams have ended. The ulParam parameter is not used and should be zero.
MFVP_MESSAGE_STEP
Value: 0x6
Requests a frame step. The lower DWORD of the ulParam parameter contains the number of frames to step. If the value is N, the presenter should skip N–1 frames and display the Nth frame. When that frame has been displayed, the presenter should send an EC_STEP_COMPLETE event to the EVR. If the presenter is not paused when it receives this message, it should return MF_E_INVALIDREQUEST.
MFVP_MESSAGE_CANCELSTEP
Value: 0x7
Cancels a frame step. The ulParam parameter is not used and should be zero.

Requirements

Requirement Value
Minimum supported client Windows Vista [desktop apps only]
Minimum supported server Windows Server 2008 [desktop apps only]
Header evr.h

See also

Enhanced Video Renderer

Media Foundation Enumerations