---
title: AudioStreamPacketDescription
framework: coreaudiotypes
role: symbol
role_heading: Structure
path: coreaudiotypes/audiostreampacketdescription
---

# AudioStreamPacketDescription

A value that describes a packet in a buffer of audio data.

## Declaration

```swift
struct AudioStreamPacketDescription
```

## Overview

Overview For data formats where the packet size isn’t constant, such as variable bit rate data and data where the channels have unequal sizes, use this structure to supplement the information in the AudioStreamBasicDescription structure.

## Topics

### Inspecting an audio stream packet description

- [mDataByteSize](coreaudiotypes/audiostreampacketdescription/mdatabytesize.md)
- [mStartOffset](coreaudiotypes/audiostreampacketdescription/mstartoffset.md)
- [mVariableFramesInPacket](coreaudiotypes/audiostreampacketdescription/mvariableframesinpacket.md)

### Creating an audio stream packet descripiton

- [init()](coreaudiotypes/audiostreampacketdescription/init().md)
- [init(mStartOffset:mVariableFramesInPacket:mDataByteSize:)](coreaudiotypes/audiostreampacketdescription/init(mstartoffset:mvariableframesinpacket:mdatabytesize:).md)

## Relationships

### Conforms To

- [BitwiseCopyable](swift/bitwisecopyable.md)
- [Sendable](swift/sendable.md)

## See Also

### Streams

- [AudioStreamBasicDescription](coreaudiotypes/audiostreambasicdescription.md)
- [AudioFormatFlags](coreaudiotypes/audioformatflags.md)
- [Audio Format Flags](coreaudiotypes/audio-format-flags.md)
- [AudioFormatID](coreaudiotypes/audioformatid.md)
- [Audio Format Identifiers](coreaudiotypes/audio-format-identifiers.md)
- [kAudioStreamAnyRate](coreaudiotypes/kaudiostreamanyrate.md)
- [MPEG4ObjectID](coreaudiotypes/mpeg4objectid.md)