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# AVAssetWriterInputCaptionAdaptor

An object that appends captions to an asset writer input.

```
class AVAssetWriterInputCaptionAdaptor
```

## Topics

### Creating a caption adaptor

[`-  initWithAssetWriterInput:`](/documentation/AVFoundation/AVAssetWriterInputCaptionAdaptor/init(assetWriterInput:))

Creates a new caption adaptor that writes to the specified asset writer input.

[`+  assetWriterInputCaptionAdaptorWithAssetWriterInput:`](/documentation/AVFoundation/AVAssetWriterInputCaptionAdaptor/assetWriterInputCaptionAdaptorWithAssetWriterInput:)

A class method that creates a new caption adaptor that writes to the specified asset writer input.

### Accessing the writer input

[`assetWriterInput`](/documentation/AVFoundation/AVAssetWriterInputCaptionAdaptor/assetWriterInput)

The associated asset writer input.

### Appending captions

[`-  appendCaption:`](/documentation/AVFoundation/AVAssetWriterInputCaptionAdaptor/append(_:)-910lp)

Appends a caption to the writer input.

[`-  appendCaptionGroup:`](/documentation/AVFoundation/AVAssetWriterInputCaptionAdaptor/append(_:)-4ils8)

Appends a caption group that the system writes to the output.

## Relationships

### Conforms To

[`CustomDebugStringConvertible`](/documentation/Swift/CustomDebugStringConvertible)

[`CustomStringConvertible`](/documentation/Swift/CustomStringConvertible)

[`Hashable`](/documentation/Swift/Hashable)

[`NSObjectProtocol`](/documentation/ObjectiveC/NSObjectProtocol)

[`Equatable`](/documentation/Swift/Equatable)

[`CVarArg`](/documentation/Swift/CVarArg)

### Inherits From

[`NSObject-swift.class`](/documentation/ObjectiveC/NSObject-swift.class)

---

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