MediaFrameReference MediaFrameReference MediaFrameReference MediaFrameReference MediaFrameReference Class

Definition

A wrapper class that represents a frame obtained from a MediaFrameSource. Use the properties of this class to access the specific frame type provided by the source, such as a VideoMediaFrame or BufferMediaFrame.

public : sealed class MediaFrameReference : IClosable, IMediaFrameReference
struct winrt::Windows::Media::Capture::Frames::MediaFrameReference : IClosable, IMediaFrameReference
public sealed class MediaFrameReference : IDisposable, IMediaFrameReference
Public NotInheritable Class MediaFrameReference Implements IDisposable, IMediaFrameReference
// This class does not provide a public constructor.
Attributes
Windows 10 requirements
Device family
Windows 10 Anniversary Edition (introduced v10.0.14393.0)
API contract
Windows.Foundation.UniversalApiContract (introduced v3)

Remarks

To get an instance of MediaFrameReference from a media frame source, create a MediaFrameReader by calling CreateFrameReaderAsync on a MediaCapture object that has been initialized to use the desired media frame source. After the frame reader has been started by calling StartAsync, call TryAcquireLatestFrame to get a MediaFrameReference representing the latest frame from the media frame source.

Each MediaFrameReader maintains a circular buffer of MediaFrameReference objects obtained from TryAcquireLatestFrame. After all of the MediaFrameReference objects in the buffer have been used, subsequent calls to TryAcquireLatestFrame will cause the system to call Close (or Dispose in C#) on the oldest buffer object in order to reuse it. Once the object has been disposed, you can no longer use it to access the frame data. For this reason, you should not store the MediaFrameReference object longer than you actually need to process the frame. If your app scenario requires you to keep a reference to the data for longer, you should use one of the APIs provided to get the underlying data. These include:

It is the responsibility of the app to call Close (or Dispose) on the objects returned by these APIs when they are no longer being used.

Important

If you access the SoftwareBitmap or Direct3DSurface objects provided by the VideoMediaFrame property of a MediaFrameReference, the system creates a strong reference to these objects, which means that they will not be disposed when you call Dispose on the containing MediaFrameReference. This also applies to the SoftwareBitmap or Direct3DSurface objects provided by the VideoFrame object that you obtain from the MediaFrameReference.VideoMediaFrame property. You must explicitly call the Dispose method of the SoftwareBitmap or Direct3DSurface directly for the objects to be immediately disposed. Otherwise, the garbage collector will eventually free the memory for these objects, but you can't know when this will occur, and if the number of allocated bitmaps or surfaces exceeds the maximum amount allowed by the system, the flow of new frames will stop.

For how-to guidance on using MediaFrameSource to capture frames, see Process media frames with MediaFrameReader.

Properties

AudioMediaFrame AudioMediaFrame AudioMediaFrame AudioMediaFrame AudioMediaFrame

Gets the AudioMediaFrame wrapped by the MediaFrameReference, if that is the type of frame represented.

BufferMediaFrame BufferMediaFrame BufferMediaFrame BufferMediaFrame BufferMediaFrame

Gets the BufferMediaFrame wrapped by the MediaFrameReference, if that is the type of frame represented.

CoordinateSystem CoordinateSystem CoordinateSystem CoordinateSystem CoordinateSystem

Gets the spatial coordinate system for the referenced media frame, if one is defined.

Duration Duration Duration Duration Duration

Gets the duration of the referenced media frame.

Format Format Format Format Format

Gets the format of the reference media frame.

Properties Properties Properties Properties Properties

Gets a map of properties for the referenced frame.

SourceKind SourceKind SourceKind SourceKind SourceKind

Gets the type of MediaFrameSource from which the referenced frame originated, such as a color, infrared, or custom source.

SystemRelativeTime SystemRelativeTime SystemRelativeTime SystemRelativeTime SystemRelativeTime

Gets a timestamp that is relative to the system and is correlatable across multiple media sources on the same device.

VideoMediaFrame VideoMediaFrame VideoMediaFrame VideoMediaFrame VideoMediaFrame

Gets the VideoMediaFrame wrapped by the MediaFrameReference, if that is the type of frame represented.

Methods

Close() Close() Close() Close() Close()

Disposes of the object and associated resources.

Dispose() Dispose() Dispose() Dispose() Dispose()

Performs application-defined tasks associated with freeing, releasing, or resetting unmanaged resources.

See Also