MFVP_MESSAGE_TYPE enumeration
Defines messages for an enhanced video renderer (EVR) presenter. This enumeration is used with the IMFVideoPresenter::ProcessMessage method.
Syntax
typedef enum { MFVP_MESSAGE_FLUSH = 0x00000000, MFVP_MESSAGE_INVALIDATEMEDIATYPE = 0x00000001, MFVP_MESSAGE_PROCESSINPUTNOTIFY = 0x00000002, MFVP_MESSAGE_BEGINSTREAMING = 0x00000003, MFVP_MESSAGE_ENDSTREAMING = 0x00000004, MFVP_MESSAGE_ENDOFSTREAM = 0x00000005, MFVP_MESSAGE_STEP = 0x00000006, MFVP_MESSAGE_CANCELSTEP = 0x00000007 } MFVP_MESSAGE_TYPE;
Constants
- MFVP_MESSAGE_FLUSH
-
The presenter should discard any pending samples. The ulParam parameter is not used and should be zero.
- MFVP_MESSAGE_INVALIDATEMEDIATYPE
-
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
-
One input stream on the mixer has received a new sample. The ulParam parameter is not used and should be zero.
- MFVP_MESSAGE_BEGINSTREAMING
-
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
-
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
-
All streams have ended. The ulParam parameter is not used and should be zero.
- MFVP_MESSAGE_STEP
-
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 N th 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
-
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] |
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Header |
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See also