---
title: audioStreamPacketDescriptions()
framework: coremedia
role: symbol
role_heading: Instance Method
path: coremedia/cmsamplebuffer/audiostreampacketdescriptions()
---

# audioStreamPacketDescriptions()

Creates an array of audio stream packet descriptions for the variable bytes per packet or variable frames per packet audio data in a sample buffer.

## Declaration

```swift
func audioStreamPacketDescriptions() throws -> [AudioStreamPacketDescription]
```

## Return Value

Return Value An array of audio stream packet descriptions.

## Discussion

Discussion Constant bit rate, constant frames-per-packet audio yields an empty array. This API is specific to audio format sample buffers, and throws an invalidMediaTypeForOperation error if called on a nonaudio sample buffer.

## See Also

### Modifying Sample Buffers

- [dataBuffer](coremedia/cmsamplebuffer/databuffer.md)
- [setDataBuffer(_:)](coremedia/cmsamplebuffer/setdatabuffer(_:).md)
- [imageBuffer](coremedia/cmsamplebuffer/imagebuffer.md)
- [withAudioBufferList(blockBufferMemoryAllocator:flags:body:)](coremedia/cmsamplebuffer/withaudiobufferlist(blockbuffermemoryallocator:flags:body:).md)
- [setDataBuffer(fromAudioBufferList:blockBufferMemoryAllocator:flags:)](coremedia/cmsamplebuffer/setdatabuffer(fromaudiobufferlist:blockbuffermemoryallocator:flags:).md)
- [copyPCMData(fromRange:into:)](coremedia/cmsamplebuffer/copypcmdata(fromrange:into:).md)
- [withUnsafeAudioStreamPacketDescriptions(_:)](coremedia/cmsamplebuffer/withunsafeaudiostreampacketdescriptions(_:).md)
- [singleSampleBuffers()](coremedia/cmsamplebuffer/singlesamplebuffers().md)
- [CMSampleBuffer.SingleSampleBuffers](coremedia/cmsamplebuffer/singlesamplebuffers.md)