Class

VNTrackingRequest

The abstract superclass for image analysis requests that track unique features across multiple images or video frames.

Declaration

class VNTrackingRequest : VNImageBasedRequest

Overview

Instantiate a tracking request subclass to perform object tracking across multiple frames of an image. After initialization, configure the degree of accuracy by setting trackingLevel, and provide observations you would like to track by setting the inputObservation initial bounding box.

Topics

Configuring a Tracking Request

enum VNRequestTrackingLevel

An enumeration of tracking priorities.

var inputObservation: VNDetectedObjectObservation

The observation object defining a region to track.

var trackingLevel: VNRequestTrackingLevel

A value for specifying whether to prioritize speed or location accuracy.

var isLastFrame: Bool

A Boolean that indicates the last frame in a tracking sequence.

Relationships

Inherits From

Conforms To

See Also

Object Tracking

Tracking the User’s Face in Real Time

Detect and track faces from the selfie cam feed in real time.

Tracking Multiple Objects or Rectangles in Video

Apply Vision algorithms to track objects or rectangles throughout a video.

class VNTrackRectangleRequest

An image analysis request that tracks movement of a previously identified rectangular object across multiple images or video frames.

class VNTrackObjectRequest

An image analysis request that tracks movement of a previously identified arbitrary object across multiple images or video frames.

class VNDetectedObjectObservation

An image analysis result that provides the position and extent of a detected image feature.

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