MFVP_MESSAGE_TYPE enumeration (evr.h)

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

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