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# AVCaptionUnitsType

A structure that defines a units for caption formats.

```
enum AVCaptionUnitsType
```

## Overview

Some geometry values may use sizing and positioning with different units. In some cases, an object might allow multiple kinds of dimensions varying by units.

## Topics

### Unit types

[`AVCaptionUnitsTypeCells`](/documentation/AVFoundation/AVCaptionUnitsType/cells)

A cell-based unit type.

[`AVCaptionUnitsTypePercent`](/documentation/AVFoundation/AVCaptionUnitsType/percent)

A percentage-based unit type.

[`AVCaptionUnitsTypeUnspecified`](/documentation/AVFoundation/AVCaptionUnitsType/unspecified)

An unspecified unit type.

## Relationships

### Conforms To

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

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

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

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

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

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

---

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