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

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

```
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

A flag representing whether the object can be tracked.

## Discussion

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

---

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