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# preferBackgroundProcessing

A hint to minimize the resource burden of the request.

```
var preferBackgroundProcessing: Bool { get set }
```

## Discussion

If set to <doc://com.apple.documentation/documentation/Swift/true>, this property reduces the request’s memory footprint, processing footprint, and CPU/GPU contention at the potential cost of longer execution time.

Setting this value can help ensure that Vision processing doesn’t block UI updates and other rendering on the main thread.

---

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