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# kAudioFormatProperty_BitmapForLayoutTag

A bitmap for an `AudioChannelLayoutTag` value.

```
var kAudioFormatProperty_BitmapForLayoutTag: AudioFormatPropertyID { get }
```

## Discussion

A bitmap for an <doc://com.apple.documentation/documentation/CoreAudioTypes/AudioChannelLayoutTag> value, if there is one. Set the `inSpecifier` parameter to an `AudioChannelLayoutTag` value containing the layout tag. The value is an `UInt32` bitmap. The bits are as defined in <doc://com.apple.documentation/documentation/CoreAudio/core-audio-data-types>. To go in the other direction, that is, to get a layout tag for a bitmap, use the [`kAudioFormatProperty_TagForChannelLayout`](/documentation/AudioToolbox/kAudioFormatProperty_TagForChannelLayout) where your layout tag is <doc://com.apple.documentation/documentation/CoreAudioTypes/kAudioChannelLayoutTag_UseChannelBitmap> and the bitmap is filled in.

---

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