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  "identifier" : "/documentation/CoreMedia/CMFormatDescription/Extensions-swift.struct/Key",
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  "title" : "CMFormatDescription.Extensions.Key"
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# CMFormatDescription.Extensions.Key

```
struct Key
```

## Topics

### Extension Keys

[`static let alphaChannelMode: CMFormatDescription.Extensions.Key`](/documentation/CoreMedia/CMFormatDescription/Extensions-swift.struct/Key/alphaChannelMode)

[`static let alternativeTransferCharacteristics: CMFormatDescription.Extensions.Key`](/documentation/CoreMedia/CMFormatDescription/Extensions-swift.struct/Key/alternativeTransferCharacteristics)

[`static let ambientViewingEnvironment: CMFormatDescription.Extensions.Key`](/documentation/CoreMedia/CMFormatDescription/Extensions-swift.struct/Key/ambientViewingEnvironment)

[`static let auxiliaryTypeInfo: CMFormatDescription.Extensions.Key`](/documentation/CoreMedia/CMFormatDescription/Extensions-swift.struct/Key/auxiliaryTypeInfo)

[`static let backgroundColor: CMFormatDescription.Extensions.Key`](/documentation/CoreMedia/CMFormatDescription/Extensions-swift.struct/Key/backgroundColor)

[`static let bitsPerComponent: CMFormatDescription.Extensions.Key`](/documentation/CoreMedia/CMFormatDescription/Extensions-swift.struct/Key/bitsPerComponent)

[`static let bytesPerRow: CMFormatDescription.Extensions.Key`](/documentation/CoreMedia/CMFormatDescription/Extensions-swift.struct/Key/bytesPerRow)

[`static let chromaLocationBottomField: CMFormatDescription.Extensions.Key`](/documentation/CoreMedia/CMFormatDescription/Extensions-swift.struct/Key/chromaLocationBottomField)

[`static let chromaLocationTopField: CMFormatDescription.Extensions.Key`](/documentation/CoreMedia/CMFormatDescription/Extensions-swift.struct/Key/chromaLocationTopField)

[`static let cleanAperture: CMFormatDescription.Extensions.Key`](/documentation/CoreMedia/CMFormatDescription/Extensions-swift.struct/Key/cleanAperture)

[`static let colorPrimaries: CMFormatDescription.Extensions.Key`](/documentation/CoreMedia/CMFormatDescription/Extensions-swift.struct/Key/colorPrimaries)

[`static let conformsToMPEG2VideoProfile: CMFormatDescription.Extensions.Key`](/documentation/CoreMedia/CMFormatDescription/Extensions-swift.struct/Key/conformsToMPEG2VideoProfile)

[`static let containsAlphaChannel: CMFormatDescription.Extensions.Key`](/documentation/CoreMedia/CMFormatDescription/Extensions-swift.struct/Key/containsAlphaChannel)

[`static let contentLightLevelInfo: CMFormatDescription.Extensions.Key`](/documentation/CoreMedia/CMFormatDescription/Extensions-swift.struct/Key/contentLightLevelInfo)

[`static let defaultFontName: CMFormatDescription.Extensions.Key`](/documentation/CoreMedia/CMFormatDescription/Extensions-swift.struct/Key/defaultFontName)

[`static let defaultStyle: CMFormatDescription.Extensions.Key`](/documentation/CoreMedia/CMFormatDescription/Extensions-swift.struct/Key/defaultStyle)

[`static let defaultTextBox: CMFormatDescription.Extensions.Key`](/documentation/CoreMedia/CMFormatDescription/Extensions-swift.struct/Key/defaultTextBox)

[`static let depth: CMFormatDescription.Extensions.Key`](/documentation/CoreMedia/CMFormatDescription/Extensions-swift.struct/Key/depth)

[`static let displayFlags: CMFormatDescription.Extensions.Key`](/documentation/CoreMedia/CMFormatDescription/Extensions-swift.struct/Key/displayFlags)

[`static let fieldCount: CMFormatDescription.Extensions.Key`](/documentation/CoreMedia/CMFormatDescription/Extensions-swift.struct/Key/fieldCount)

[`static let fieldDetail: CMFormatDescription.Extensions.Key`](/documentation/CoreMedia/CMFormatDescription/Extensions-swift.struct/Key/fieldDetail)

[`static let fontTable: CMFormatDescription.Extensions.Key`](/documentation/CoreMedia/CMFormatDescription/Extensions-swift.struct/Key/fontTable)

[`static let formatName: CMFormatDescription.Extensions.Key`](/documentation/CoreMedia/CMFormatDescription/Extensions-swift.struct/Key/formatName)

[`static let fullRangeVideo: CMFormatDescription.Extensions.Key`](/documentation/CoreMedia/CMFormatDescription/Extensions-swift.struct/Key/fullRangeVideo)

[`static let gammaLevel: CMFormatDescription.Extensions.Key`](/documentation/CoreMedia/CMFormatDescription/Extensions-swift.struct/Key/gammaLevel)

[`static let horizontalJustification: CMFormatDescription.Extensions.Key`](/documentation/CoreMedia/CMFormatDescription/Extensions-swift.struct/Key/horizontalJustification)

[`static let iccProfile: CMFormatDescription.Extensions.Key`](/documentation/CoreMedia/CMFormatDescription/Extensions-swift.struct/Key/iccProfile)

[`static let masteringDisplayColorVolume: CMFormatDescription.Extensions.Key`](/documentation/CoreMedia/CMFormatDescription/Extensions-swift.struct/Key/masteringDisplayColorVolume)

[`static let metadataKeyTable: CMFormatDescription.Extensions.Key`](/documentation/CoreMedia/CMFormatDescription/Extensions-swift.struct/Key/metadataKeyTable)

[`static let originalCompressionSettings: CMFormatDescription.Extensions.Key`](/documentation/CoreMedia/CMFormatDescription/Extensions-swift.struct/Key/originalCompressionSettings)

[`static let pixelAspectRatio: CMFormatDescription.Extensions.Key`](/documentation/CoreMedia/CMFormatDescription/Extensions-swift.struct/Key/pixelAspectRatio)

[`static let revisionLevel: CMFormatDescription.Extensions.Key`](/documentation/CoreMedia/CMFormatDescription/Extensions-swift.struct/Key/revisionLevel)

[`static let sampleDescriptionExtensionAtoms: CMFormatDescription.Extensions.Key`](/documentation/CoreMedia/CMFormatDescription/Extensions-swift.struct/Key/sampleDescriptionExtensionAtoms)

[`static let sourceReferenceName: CMFormatDescription.Extensions.Key`](/documentation/CoreMedia/CMFormatDescription/Extensions-swift.struct/Key/sourceReferenceName)

[`static let spatialQuality: CMFormatDescription.Extensions.Key`](/documentation/CoreMedia/CMFormatDescription/Extensions-swift.struct/Key/spatialQuality)

[`static let temporalQuality: CMFormatDescription.Extensions.Key`](/documentation/CoreMedia/CMFormatDescription/Extensions-swift.struct/Key/temporalQuality)

[`static let textJustification: CMFormatDescription.Extensions.Key`](/documentation/CoreMedia/CMFormatDescription/Extensions-swift.struct/Key/textJustification)

[`static let transferFunction: CMFormatDescription.Extensions.Key`](/documentation/CoreMedia/CMFormatDescription/Extensions-swift.struct/Key/transferFunction)

[`static let vendor: CMFormatDescription.Extensions.Key`](/documentation/CoreMedia/CMFormatDescription/Extensions-swift.struct/Key/vendor)

[`static let verbatimISOSampleEntry: CMFormatDescription.Extensions.Key`](/documentation/CoreMedia/CMFormatDescription/Extensions-swift.struct/Key/verbatimISOSampleEntry)

[`static let verbatimSampleDescription: CMFormatDescription.Extensions.Key`](/documentation/CoreMedia/CMFormatDescription/Extensions-swift.struct/Key/verbatimSampleDescription)

[`static let version: CMFormatDescription.Extensions.Key`](/documentation/CoreMedia/CMFormatDescription/Extensions-swift.struct/Key/version)

[`static let verticalJustification: CMFormatDescription.Extensions.Key`](/documentation/CoreMedia/CMFormatDescription/Extensions-swift.struct/Key/verticalJustification)

[`static let yCbCrMatrix: CMFormatDescription.Extensions.Key`](/documentation/CoreMedia/CMFormatDescription/Extensions-swift.struct/Key/yCbCrMatrix)

### Initializers

[`init(rawValue: CFString)`](/documentation/CoreMedia/CMFormatDescription/Extensions-swift.struct/Key/init(rawValue:))

Creates a new `Key` backed by `rawValue`

### Type Properties

[`static let cameraCalibrationDataLensCollection: CMFormatDescription.Extensions.Key`](/documentation/CoreMedia/CMFormatDescription/Extensions-swift.struct/Key/cameraCalibrationDataLensCollection)

Specifies intrinsic and extrinsic parameters for single or multiple lenses. The value for this key is
represented by [`CMFormatDescription.Extensions.Value.CameraCalibrationDataLensCollection`](/documentation/CoreMedia/CMFormatDescription/Extensions-swift.struct/Value/CameraCalibrationDataLensCollection) type.

[`static var contentColorVolume: CMFormatDescription.Extensions.Key`](/documentation/CoreMedia/CMFormatDescription/Extensions-swift.struct/Key/contentColorVolume)

Matches payload of ITU-T-H.265:11/2019, D.2.40 Content Colour Volume SEI message. The value of this key
is of [`CMFormatDescription.Extensions.Value.ContentColorVolume`](/documentation/CoreMedia/CMFormatDescription/Extensions-swift.struct/Value/ContentColorVolume) type.

[`static let convertedFromExternalSphericalTags: CMFormatDescription.Extensions.Key`](/documentation/CoreMedia/CMFormatDescription/Extensions-swift.struct/Key/convertedFromExternalSphericalTags)

Indicates that the image description contains projected media data converted from an external format.

[`static var hasAdditionalViews: CMFormatDescription.Extensions.Key`](/documentation/CoreMedia/CMFormatDescription/Extensions-swift.struct/Key/hasAdditionalViews)

A boolean indicating that one or more additional views may be present beyond stereo left and stereo
right eyes (e.g,. a “centerline” view).

[`static var hasLeftStereoEyeView: CMFormatDescription.Extensions.Key`](/documentation/CoreMedia/CMFormatDescription/Extensions-swift.struct/Key/hasLeftStereoEyeView)

A boolean indicating the stereo left eye is present in video frames.

[`static var hasRightStereoEyeView: CMFormatDescription.Extensions.Key`](/documentation/CoreMedia/CMFormatDescription/Extensions-swift.struct/Key/hasRightStereoEyeView)

A boolean indicating the stereo right eye is present in video frames.

[`static var heroEye: CMFormatDescription.Extensions.Key`](/documentation/CoreMedia/CMFormatDescription/Extensions-swift.struct/Key/heroEye)

Indicates which of the two eyes should be used as the primary when rendering in 2D. It is usually
perpendicular to the target image surface.

[`static var horizontalDisparityAdjustment: CMFormatDescription.Extensions.Key`](/documentation/CoreMedia/CMFormatDescription/Extensions-swift.struct/Key/horizontalDisparityAdjustment)

Indicates a relative shift of the left and right images, which changes the zero parallax plane.

[`static var horizontalFieldOfView: CMFormatDescription.Extensions.Key`](/documentation/CoreMedia/CMFormatDescription/Extensions-swift.struct/Key/horizontalFieldOfView)

Horizontal field of view in thousandths of a degree (i.e., 123456 is 123.456 degrees).

[`static var logTransferFunction: CMFormatDescription.Extensions.Key`](/documentation/CoreMedia/CMFormatDescription/Extensions-swift.struct/Key/logTransferFunction)

Indicates that the transfer function or gamma of the content is a log format and identifies the
specific log curve.

[`static var projectionKind: CMFormatDescription.Extensions.Key`](/documentation/CoreMedia/CMFormatDescription/Extensions-swift.struct/Key/projectionKind)

Indicates the projection that should be applied to presented decoded video frames.

[`static var protectedContentOriginalFormat: CMFormatDescription.Extensions.Key`](/documentation/CoreMedia/CMFormatDescription/Extensions-swift.struct/Key/protectedContentOriginalFormat)

FourCharCode number representing the original format

[`static var stereoCameraBaseline: CMFormatDescription.Extensions.Key`](/documentation/CoreMedia/CMFormatDescription/Extensions-swift.struct/Key/stereoCameraBaseline)

Indicates the distance between centers of the lenses of the camera system.

[`static let viewPackingKind: CMFormatDescription.Extensions.Key`](/documentation/CoreMedia/CMFormatDescription/Extensions-swift.struct/Key/viewPackingKind)

Indicates the packing type of stereoscopic video frames.

## Relationships

### Conforms To

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

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

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

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

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

---

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