---
title: AVSpeechSynthesizer.BufferCallback
framework: avfaudio
role: symbol
role_heading: Type Alias
path: avfaudio/avspeechsynthesizer/buffercallback
---

# AVSpeechSynthesizer.BufferCallback

A type that defines a callback that receives a buffer of generated speech.

## Declaration

```swift
typealias BufferCallback = (AVAudioBuffer) -> Void
```

## See Also

### Directing speech output

- [usesApplicationAudioSession](avfaudio/avspeechsynthesizer/usesapplicationaudiosession.md)
- [mixToTelephonyUplink](avfaudio/avspeechsynthesizer/mixtotelephonyuplink.md)
- [outputChannels](avfaudio/avspeechsynthesizer/outputchannels.md)
- [write(_:toBufferCallback:)](avfaudio/avspeechsynthesizer/write(_:tobuffercallback:).md)
- [write(_:toBufferCallback:toMarkerCallback:)](avfaudio/avspeechsynthesizer/write(_:tobuffercallback:tomarkercallback:).md)
- [AVSpeechSynthesizer.MarkerCallback](avfaudio/avspeechsynthesizer/markercallback.md)