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# kCMMetadataKeySpace_QuickTimeUserData

Metadata keyspace for QuickTime User Data keys.

```
let kCMMetadataKeySpace_QuickTimeUserData: CFString
```

## Discussion

This keyspace defines its key values to be expressed as `OSType`s (a.k.a. `FourCharCode`s). As such, keys must be four bytes in length.

---

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