LowLagPhotoSequenceControl Class

Reference

Definition

Namespace:: Windows.Media.Devices

Important

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Edit

Provides functionality for managing the low shutter lag photo sequence mode on the capture device.

public ref class LowLagPhotoSequenceControl sealed

/// [Windows.Foundation.Metadata.ContractVersion(Windows.Foundation.UniversalApiContract, 65536)]
/// [Windows.Foundation.Metadata.MarshalingBehavior(Windows.Foundation.Metadata.MarshalingType.Standard)]
/// [Windows.Foundation.Metadata.Threading(Windows.Foundation.Metadata.ThreadingModel.MTA)]
class LowLagPhotoSequenceControl final

[Windows.Foundation.Metadata.ContractVersion(typeof(Windows.Foundation.UniversalApiContract), 65536)]
[Windows.Foundation.Metadata.MarshalingBehavior(Windows.Foundation.Metadata.MarshalingType.Standard)]
[Windows.Foundation.Metadata.Threading(Windows.Foundation.Metadata.ThreadingModel.MTA)]
public sealed class LowLagPhotoSequenceControl

Public NotInheritable Class LowLagPhotoSequenceControl

Inheritance: Object Platform::Object IInspectable LowLagPhotoSequenceControl

Attributes: ContractVersionAttribute MarshalingBehaviorAttribute ThreadingAttribute

Windows requirements

Device family	Windows 10 (introduced in 10.0.10240.0)
API contract	Windows.Foundation.UniversalApiContract (introduced in v1.0)

Remarks

Photo sequence mode takes a rapid sequence of photos. A key scenario for photo sequence is getting photos in the past, that is prior to when the user takes a photo.

You can access the LowLagPhotoSequenceControl for the capture device through MediaCapture.VideoDeviceController.

You can find out if the device supports photo sequence mode by checking LowLagPhotoSequenceControl.Supported.

To initiate photo sequence mode, call MediaCapture.PrepareLowLagPhotoSequenceCaptureAsync. To start capturing photos, call StartAsync. To stop capturing photos, call StopAsync. The app will continue to receive photos from the device until the operation is stopped.

GetCurrentFrameRate specifies the frame rate at which the photos are taken.

PhotoCapturedEventArgs.CaptureTimeOffset can be used to tell whether a frame was in the future, greater than 0, or in the past, less than 0.

If the app wants to limit how many frames it gets per second, it can use LowLagPhotoSequence.PhotosPerSecondLimit. This can be useful in situations where the sensor on the device can handle 30fps, but the app only needs 4fps.

Thumbnails are supported for a low shutter lag single photos and photo sequences.

To enable thumbnails, set ThumbnailEnabled to true.

You can set the desired thumbnail size through DesiredThumbnailSize and set the thumbnail format through ThumbnailFormat.

The number of past photos cannot be more than MaxPastPhotos, which is the maximum number of past photos that is supported by the driver. The number of past photos returned will be the smaller of the following values: PastPhotoLimit, MaxPastPhotos, or the current number of available past photos.

Properties

DesiredThumbnailSize	Gets or sets the desired size for thumbnails, which is the largest length of the image, either width or height.
HardwareAcceleratedThumbnailSupported	Gets a value that specifies if hardware acceleration is supported for thumbnails in photo sequence mode.
MaxPastPhotos	Gets the maximum number of past photos that can be stored.
MaxPhotosPerSecond	Gets the maximum number of photos that can be taken per second.
PastPhotoLimit	Gets or sets a value that specifies the number of past photos to store.
PhotosPerSecondLimit	Gets or sets the number of photos that are taken per second.
Supported	Gets a value that specifies if the capture device supports low shutter lag photo sequence mode.
ThumbnailEnabled	Gets a value that enables and disables thumbnail support in photo sequence mode.
ThumbnailFormat	Gets or sets the media format for the thumbnails.

Methods

GetCurrentFrameRate()	Gets the current frame rate at which pictures can be taken.
GetHighestConcurrentFrameRate(IMediaEncodingProperties)	Gets the highest frame rate supported when video and photos sequences are being captured concurrently.

Applies to

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