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# AVAssetWriterInput.CaptionReceiver

Provides an interface for writing caption data to an input.

```
class CaptionReceiver
```

## Topics

### Appending captions

[`func append(AVCaptionGroup) async throws`](/documentation/AVFoundation/AVAssetWriterInput/CaptionReceiver/append(_:)-4opbd)

Suspends until the input is ready for more media data, then appends the caption group.              

[`func append(AVCaption) async throws`](/documentation/AVFoundation/AVAssetWriterInput/CaptionReceiver/append(_:)-4wpi2)

Suspends until the input is ready for more media data, then appends the caption.                   

[`func appendImmediately(AVCaptionGroup) throws -> Bool`](/documentation/AVFoundation/AVAssetWriterInput/CaptionReceiver/appendImmediately(_:)-7q21r)

Appends the caption group synchronously if the input is ready for more media data.   

[`func appendImmediately(AVCaption) throws -> Bool`](/documentation/AVFoundation/AVAssetWriterInput/CaptionReceiver/appendImmediately(_:)-9uy14)

Appends the caption synchronously if the input is ready for more media data.        

[`func finish()`](/documentation/AVFoundation/AVAssetWriterInput/CaptionReceiver/finish())

Indicates to the AVAssetWriter that no more buffers will be appended to this receiver.


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