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# setBackgroundImageData(_:)

Changes the background image of the group container to the image in the specified data object.

```
func setBackgroundImageData(_ imageData: Data?)
```

## Parameters

`imageData`

A data object containing the image data in its native format. Specifying `nil` removes the existing image, causing the watch interface to display nothing in the space previously occupied by the image.

## Discussion

Use this method when you already have image data in the raw PNG or JPG format. This method sends the data as-is, which lets you send the data in a compressed format. Sending compressed data is often more efficient than sending a <doc://com.apple.documentation/documentation/UIKit/UIImage> object.

---

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