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# kAudioFileStreamProperty_FileFormat

A four-character code that identifies the audio data format.

```
var kAudioFileStreamProperty_FileFormat: AudioFileStreamPropertyID { get }
```

## Discussion

A `UInt32` four-character code that identifies the audio data format. For a list of audio format IDs, see “Audio Data Format IDs” in <doc://com.apple.documentation/documentation/CoreAudio/core-audio-data-types>.

---

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