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# rdd18UserItems

An AVCaptureAncillaryDataEncoder key corresponding with RDD18 user defined metadata

```
static let rdd18UserItems: AVCaptureAncillaryDataUserKey
```

## Discussion

Clients may inspect the user metadata with `AVCaptureAncillaryDataEncoder\currentUserDefinedAncillaryData` and set it with `AVCaptureAncillaryDataEncoder\setRDD18AncillaryData:forTag:error:` `AVCaptureAncillaryDataEncoder\setRDD18AncillaryDataString:forTag:error:` or remove it with `AVCaptureAncillaryDataEncoder\removeRDD18AncillaryDataForTag:`

---

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