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# CMAudioFormatDescriptionCreateFromBigEndianSoundDescriptionBlockBuffer(allocator:bigEndianSoundDescriptionBlockBuffer:flavor:formatDescriptionOut:)

Creates an audio format description from a big-endian sound description data structure in a buffer.

```
func CMAudioFormatDescriptionCreateFromBigEndianSoundDescriptionBlockBuffer(allocator: CFAllocator?, bigEndianSoundDescriptionBlockBuffer soundDescriptionBlockBuffer: CMBlockBuffer, flavor: CMSoundDescriptionFlavor?, formatDescriptionOut: UnsafeMutablePointer<CMAudioFormatDescription?>) -> OSStatus
```

## Parameters

`allocator`

Allocator to use for allocating the CMAudioFormatDescription object. May be NULL.

`soundDescriptionBlockBuffer`

CMBlockBuffer containing SoundDescription data structure in big-endian byte ordering.

`flavor`

kCMSoundDescriptionFlavor constant or NULL for QuickTimeMovie flavor.

`formatDescriptionOut`

Receives new CMAudioFormatDescription.

## Discussion

---

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