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# AVCaptionRegion

An object that represents the region in which the system presents a caption.

```
class AVCaptionRegion
```

## Overview

The framework defines four regions, and doesn’t support configuring region settings.

## Topics

### Accessing defined regions

[`appleITTTop`](/documentation/AVFoundation/AVCaptionRegion/appleITTTop)

The top region for iTT format captions.

[`appleITTBottom`](/documentation/AVFoundation/AVCaptionRegion/appleITTBottom)

The bottom region for iTT format captions.

[`appleITTLeft`](/documentation/AVFoundation/AVCaptionRegion/appleITTLeft)

The left region for iTT format captions.

[`appleITTRight`](/documentation/AVFoundation/AVCaptionRegion/appleITTRight)

The right region for iTT format captions.

[`subRipTextBottom`](/documentation/AVFoundation/AVCaptionRegion/subRipTextBottom)

The bottom caption region for SubRip Text (SRT) format captions.

### Identifying a region

[`identifier`](/documentation/AVFoundation/AVCaptionRegion/identifier)

A string that identifies the region.

### Accessing dimensions

[`AVCaptionDimension`](/documentation/AVFoundation/AVCaptionDimension)

A structure that defines a caption dimension.

[`AVCaptionDimensionMake`](/documentation/AVFoundation/AVCaptionDimensionMake)

Creates a caption dimension with a value and unit type.

### Accessing the location

[`origin`](/documentation/AVFoundation/AVCaptionRegion/origin)

The region’s top-left position.

[`AVCaptionPoint`](/documentation/AVFoundation/AVCaptionPoint)

A structure that defines the origin point for a caption.

[`AVCaptionPointMake`](/documentation/AVFoundation/AVCaptionPointMake)

Creates a caption point with the specified x and y positions.

### Accessing the size

[`size`](/documentation/AVFoundation/AVCaptionRegion/size)

The height and width of the region.

[`AVCaptionSize`](/documentation/AVFoundation/AVCaptionSize)

A structure that defines the height and width of a caption.

[`AVCaptionSizeMake`](/documentation/AVFoundation/AVCaptionSizeMake)

Creates a caption size with the specified width and height.

### Accessing the display alignment

[`displayAlignment`](/documentation/AVFoundation/AVCaptionRegion/displayAlignment-swift.property)

The alignment of lines for the region.

[`AVCaptionRegion.DisplayAlignment`](/documentation/AVFoundation/AVCaptionRegion/DisplayAlignment-swift.enum)

Constants that indicate the alignment of lines in a region.

### Accessing the scroll mode

[`scroll`](/documentation/AVFoundation/AVCaptionRegion/scroll-swift.property)

The scroll mode of the region.

[`AVCaptionRegion.Scroll`](/documentation/AVFoundation/AVCaptionRegion/Scroll-swift.enum)

Constants that indicate the scrolling effects the system applies to a region.

### Accessing the writing mode

[`writingMode`](/documentation/AVFoundation/AVCaptionRegion/writingMode-swift.property)

The block and inline progression direction of the region.

[`AVCaptionRegion.WritingMode`](/documentation/AVFoundation/AVCaptionRegion/WritingMode-swift.enum)

Constants that indicate the writing mode for a region.

### Processing regions

[`mutableCopy(with:)`](/documentation/AVFoundation/AVCaptionRegion/mutableCopy(with:))

Creates a mutable copy of a caption region.

[`encode(with:)`](/documentation/AVFoundation/AVCaptionRegion/encode(with:))

Encodes the region using the specified encoder.

[`isEqual(_:)`](/documentation/AVFoundation/AVCaptionRegion/isEqual(_:))

Returns a Boolean value that indicates whether an object equals another.


---

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