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# kVTDecompressionPropertyKey_RealTime

A Boolean value indicating whether it’s recommended that the video decoder perform decompression in real time.

```
let kVTDecompressionPropertyKey_RealTime: CFString
```

## Discussion

For non-realtime decompression, clients may set this property to <doc://com.apple.documentation/documentation/CoreFoundation/kCFBooleanFalse>, which indicates that it is OK to run this decode pipeline at a lower priority than is used for realtime decoding. By default, VideoToolbox will treat the decompression session as though it is being used for realtime playback (<doc://com.apple.documentation/documentation/CoreFoundation/kCFBooleanTrue>).  Setting the property to `NULL` is equivalent to setting it to <doc://com.apple.documentation/documentation/CoreFoundation/kCFBooleanTrue>.

---

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