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# init(format:packetCapacity:maximumPacketSize:)

Creates a buffer that contains audio data in a compressed state.

```
init(format: AVAudioFormat, packetCapacity: AVAudioPacketCount, maximumPacketSize: Int)
```

## Parameters

`format`

The format of the audio the buffer contains.

`packetCapacity`

The capacity of the buffer, in packets.

`maximumPacketSize`

The maximum size in bytes of a packet in a compressed state.

## Return Value

A new [`AVAudioCompressedBuffer`](/documentation/AVFAudio/AVAudioCompressedBuffer) instance.

## Discussion

You can obtain the maximum packet size from the [`maximumOutputPacketSize`](/documentation/AVFAudio/AVAudioConverter/maximumOutputPacketSize) property of an [`AVAudioConverter`](/documentation/AVFAudio/AVAudioConverter) you configure for encoding this format.

The method raises an exception if the format is PCM.

---

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