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# CMFormatDescription.EqualityMask

A type that describes format description equality masks.

```
struct EqualityMask
```

## Topics

### Equality Masks

[`static let all: CMFormatDescription.EqualityMask`](/documentation/CoreMedia/CMFormatDescription/EqualityMask/all)

[`static let channelLayout: CMFormatDescription.EqualityMask`](/documentation/CoreMedia/CMFormatDescription/EqualityMask/channelLayout)

[`static let extensions: CMFormatDescription.EqualityMask`](/documentation/CoreMedia/CMFormatDescription/EqualityMask/extensions)

[`static let magicCookie: CMFormatDescription.EqualityMask`](/documentation/CoreMedia/CMFormatDescription/EqualityMask/magicCookie)

[`static let streamBasicDescription: CMFormatDescription.EqualityMask`](/documentation/CoreMedia/CMFormatDescription/EqualityMask/streamBasicDescription)

## Relationships

### Conforms To

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

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

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

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

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

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

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

---

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