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# MTAudioProcessingTapInitCallback

An initialization callback function.

```
typealias MTAudioProcessingTapInitCallback = (MTAudioProcessingTap, UnsafeMutableRawPointer?, UnsafeMutablePointer<UnsafeMutableRawPointer?>) -> Void
```

## Parameters

`tap`

The processing tap.

`clientInfo`

The client data of the processing tap passed in callbacks struct in MTAudioProcessingTapCreate().

`tapStorageOut`

Additional client data.  The intent is for clients to allocate a block of memory for use within their custom  MTAudioProcessingTap implementation that will be freed when the finalize callback is invoked.  This argument is optional.

## Overview

An init callback that is invoked when MTAudioProcessingTapCreate() is called. The init callback is always balanced by a finalize callback when the MTAudioProcessingTap object is released.

---

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