---
title: DockAccessory.Observation
framework: dockkit
role: symbol
role_heading: Structure
path: dockkit/dockaccessory/observation
---

# DockAccessory.Observation

An observation of the contents of a single video frame.

## Declaration

```swift
struct Observation
```

## Mentioned in

Track custom objects in a frame

## Overview

Overview This object represents an observation about a single video frame, including information about the type of subject, the coordinates of the subject, and the angle of the subject’s face. DockKit generates tracking vectors from this frame information. When performing your own tracking, you provide one or more DockAccessory.Observation objects to track(_:cameraInformation:).

## Topics

### Creating an observation

- [init(identifier:type:rect:faceYawAngle:)](dockkit/dockaccessory/observation/init(identifier:type:rect:faceyawangle:).md)

### Getting properties

- [faceYawAngle](dockkit/dockaccessory/observation/faceyawangle.md)
- [rect](dockkit/dockaccessory/observation/rect.md)
- [type](dockkit/dockaccessory/observation/type.md)
- [identifier](dockkit/dockaccessory/observation/identifier.md)

### Defining types

- [DockAccessory.Observation.ObservationType](dockkit/dockaccessory/observation/observationtype.md)

## Relationships

### Conforms To

- [Sendable](swift/sendable.md)
- [SendableMetatype](swift/sendablemetatype.md)

## See Also

### Selecting and tracking

- [selectSubject(at:)](dockkit/dockaccessory/selectsubject(at:).md)
- [track(_:cameraInformation:)](dockkit/dockaccessory/track(_:camerainformation:)-4yl9b.md)
- [track(_:cameraInformation:)](dockkit/dockaccessory/track(_:camerainformation:)-44mwn.md)
- [DockAccessory.CameraInformation](dockkit/dockaccessory/camerainformation.md)
- [DockAccessory.CameraOrientation](dockkit/dockaccessory/cameraorientation.md)