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# MTAudioProcessingTapCallbacks

A structure that defines life cycle callbacks for an audio processing tap object.

```
struct MTAudioProcessingTapCallbacks
```

## Overview

On 64-bit architectures, this struct contains misaligned function pointers. To avoid link-time issues, fill its function pointer fields by using assignment statements, rather than declaring them as global or static structs.

## Topics

### Fields

[`version`](/documentation/MediaToolbox/MTAudioProcessingTapCallbacks/version)

The version number of the structure.

[`clientInfo`](/documentation/MediaToolbox/MTAudioProcessingTapCallbacks/clientInfo)

App data that the system passes to the initialization callback.

[`init`](/documentation/MediaToolbox/MTAudioProcessingTapCallbacks/init)

A callback to initialize the tap processor.

[`finalize`](/documentation/MediaToolbox/MTAudioProcessingTapCallbacks/finalize)

A callback to perform any necessary cleanup.

[`prepare`](/documentation/MediaToolbox/MTAudioProcessingTapCallbacks/prepare)

A callback to prepare the tap processor.

[`unprepare`](/documentation/MediaToolbox/MTAudioProcessingTapCallbacks/unprepare)

A callback to perform any necessary cleanup for previous preparation.

[`process`](/documentation/MediaToolbox/MTAudioProcessingTapCallbacks/process)

A callback for processing the audio.

### Callback functions

[`MTAudioProcessingTapInitCallback`](/documentation/MediaToolbox/MTAudioProcessingTapInitCallback)

An initialization callback function.

[`MTAudioProcessingTapPrepareCallback`](/documentation/MediaToolbox/MTAudioProcessingTapPrepareCallback)

An audio processing preparation callback function.

[`MTAudioProcessingTapProcessCallback`](/documentation/MediaToolbox/MTAudioProcessingTapProcessCallback)

An audio processing callback function.

[`MTAudioProcessingTapUnprepareCallback`](/documentation/MediaToolbox/MTAudioProcessingTapUnprepareCallback)

An audio processing unpreparation callback function.

[`MTAudioProcessingTapFinalizeCallback`](/documentation/MediaToolbox/MTAudioProcessingTapFinalizeCallback)

A finalization callback function.

### Versions

[`kMTAudioProcessingTapCallbacksVersion_0`](/documentation/MediaToolbox/kMTAudioProcessingTapCallbacksVersion_0)

An identifier for version 0 of the callbacks structure.


---

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