MF_PD_PLAYBACK_ELEMENT_ID attribute
Contains the identifier of the playlist element in the presentation.
Data type
UINT32
Get/set
To get this attribute, call IMFAttributes::GetUINT32.
To set this attribute, call IMFAttributes::SetUINT32.
Applies to
Remarks
Media sources that deliver playlists can optionally set this attribute on their presentation descriptors.
When a media source delivers a playlist, it sends a MENewPresentation event for each playlist element after the first. This event contains a presentation descriptor for the new playlist element. The media source can assign identifiers to the elements by setting the MF_PD_PLAYBACK_ELEMENT_ID attribute on each presentation descriptor, including the one created by IMFMediaSource::CreatePresentationDescriptor.
A media source might also send the MENewPresentation event because of a dynamic stream switch or a change in the number of streams. In that situation, the value of MF_PD_PLAYBACK_ELEMENT_ID should remain the same across both presentations, to indicate that both presentations represent the same playlist element. If two consecutive presentations have the same value for this attribute, the Microsoft Media Foundation pipeline expects the time stamps to remain continuous across the transition. Therefore, the media source must not use the MF_EVENT_SOURCE_ACTUAL_START attribute when it transitions to the next presentation.
Media sources that implement IMFMediaSourceTopologyProvider should use the MF_TOPONODE_SEQUENCE_ELEMENTID attribute rather than the MF_PD_PLAYBACK_ELEMENT_ID attribute.
The GUID constant for this attribute is exported from mfuuid.lib.
Requirements
Requirement | Value |
---|---|
Minimum supported client |
Windows 7 [desktop apps | UWP apps] |
Minimum supported server |
Windows Server 2008 R2 [desktop apps | UWP apps] |
Header |
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See also