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# kAudioFormatProperty_ChannelLayoutForBitmap

The channel descriptions for a standard channel layout,

```
var kAudioFormatProperty_ChannelLayoutForBitmap: AudioFormatPropertyID { get }
```

## Discussion

The channel descriptions for a standard channel layout, in the form of an <doc://com.apple.documentation/documentation/CoreAudioTypes/AudioChannelLayout> structure. In some uses, an <doc://com.apple.documentation/documentation/CoreAudioTypes/AudioChannelLayout> can be valid with the `mChannelLayoutTag` field set to an <doc://com.apple.documentation/documentation/CoreAudioTypes/kAudioChannelLayoutTag_UseChannelBitmap> value and the bitmap set appropriately. The specifier is a `UInt32` value representing he `mChannelBitmap` field of the <doc://com.apple.documentation/documentation/CoreAudioTypes/AudioChannelLayout> structure that contains the layout.

---

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