---
title: "startTracking(at:within:sourceImage:sourceDisparity:)"
framework: Cinematic
role: symbol
role_heading: Instance Method
platforms: [iOS 17.0+, iPadOS 17.0+, macOS 14.0+, tvOS 17.0+]
path: "cinematic/cnobjecttracker-1n598/starttracking(at:within:sourceimage:sourcedisparity:)"
---

# startTracking(at:within:sourceImage:sourceDisparity:)

Starts creating a detection track to track an object within the given bounds.

## Declaration

```swift
func startTracking(at time: CMTime, within normalizedBounds: CGRect, sourceImage: CVPixelBuffer, sourceDisparity: CVPixelBuffer) -> Bool
```

## Parameters

- `time`: The presentation time of the first frame in the detection track.
- `normalizedBounds`: The bounds of the object to track in normalized coordinates where (0.0, 0.0) is the upper-left corner, and (1.0, 1.0) is the lower-right.
- `sourceImage`: The image buffer containing the image.
- `sourceDisparity`: The disparity buffer containing depth information.

## Return Value

Return Value A flag representing whether the object can be tracked.

## Discussion

Discussion If you can track the object, the system adds a detection to the detection track you’re building.