---
title: trackingID
framework: coreimage
role: symbol
role_heading: Instance Property
path: coreimage/cifacefeature/trackingid-swift.property
---

# trackingID

The tracking identifier of the face object.

## Declaration

```swift
var trackingID: Int32 { get }
```

## Discussion

Discussion Core Image provides a tracking identifier for faces it detects in a video stream, which you can use to identify when a CIFaceFeature objects detected in one video frame is the same face detected in a previous video frame. This identifier persists only as long as a face is in the frame and is not associated with a specific face. In other words, if a face moves out of the video frame and comes back into the frame later, another ID is assigned. (Core Image detects faces, but does not recognize specific faces.)

## See Also

### Tracking Distinct Faces in Video

- [hasTrackingID](coreimage/cifacefeature/hastrackingid-swift.property.md)
- [hasTrackingFrameCount](coreimage/cifacefeature/hastrackingframecount-swift.property.md)
- [trackingFrameCount](coreimage/cifacefeature/trackingframecount-swift.property.md)