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# CVImageBufferAttachmentKeyDefinitions

A namespace for image buffer attachment keys.

```
protocol CVImageBufferAttachmentKeyDefinitions : CVAttachmentKeyDefinitions
```

## Topics

### Type Properties

[`static var alphaChannelIsOpaque: CVAttachmentKeyDefinition<Self.ShouldPropagate, Bool>`](/documentation/CoreVideo/CVImageBufferAttachmentKeyDefinitions/alphaChannelIsOpaque)

True if the alpha channel in the image data is fully opaque.

[`static var alphaChannelMode: CVAttachmentKeyDefinition<Self.ShouldPropagate, CVImageAlphaChannelMode>`](/documentation/CoreVideo/CVImageBufferAttachmentKeyDefinitions/alphaChannelMode)

Determines how the alpha channel should be rendered.

[`static var ambientViewingEnvironment: CVAttachmentKeyDefinition<Self.ShouldPropagate, Data>`](/documentation/CoreVideo/CVImageBufferAttachmentKeyDefinitions/ambientViewingEnvironment)

The ambient viewing environment for the image.
The value for this key is an 8 byte big-endian data sequence to match the payload of the Ambient Viewing Environment SEI message.

[`static var chromaField: CVAttachmentCompositeKeyDefinition<Self.ShouldPropagate, CVImageChromaField>`](/documentation/CoreVideo/CVImageBufferAttachmentKeyDefinitions/chromaField)

The chroma field information for the image buffer.

[`static var cleanAperture: CVAttachmentKeyDefinition<Self.ShouldPropagate, CVImageCleanAperture>`](/documentation/CoreVideo/CVImageBufferAttachmentKeyDefinitions/cleanAperture)

Clean aperture of the image buffer.

[`static var colorPrimaries: CVAttachmentKeyDefinition<Self.ShouldPropagate, CVImageColorPrimaries>`](/documentation/CoreVideo/CVImageBufferAttachmentKeyDefinitions/colorPrimaries)

The color primaries gamut for the image buffer.

[`static var colorSpace: CVAttachmentKeyDefinition<Self.ShouldPropagate, CGColorSpace>`](/documentation/CoreVideo/CVImageBufferAttachmentKeyDefinitions/colorSpace)

Color space of the image buffer.

[`static var contentLightLevelInfo: CVAttachmentKeyDefinition<Self.ShouldPropagate, Data>`](/documentation/CoreVideo/CVImageBufferAttachmentKeyDefinitions/contentLightLevelInfo)

The content light level information for the image.

[`static var displayDimensions: CVAttachmentKeyDefinition<Self.ShouldPropagate, CGSize>`](/documentation/CoreVideo/CVImageBufferAttachmentKeyDefinitions/displayDimensions)

Display dimensions for the image buffer.

[`static var displayMaskRectangle: CVAttachmentKeyDefinition<Self.ShouldPropagate, CVImageDisplayMaskRectangle>`](/documentation/CoreVideo/CVImageBufferAttachmentKeyDefinitions/displayMaskRectangle)

Specifies the rectangular display area within the image.

[`static var fieldDetail: CVAttachmentKeyDefinition<Self.ShouldPropagate, CVImageFieldDetail>`](/documentation/CoreVideo/CVImageBufferAttachmentKeyDefinitions/fieldDetail)

The order of interlaced video data in the image buffer.

[`static var gammaLevel: CVAttachmentKeyDefinition<Self.ShouldPropagate, Double>`](/documentation/CoreVideo/CVImageBufferAttachmentKeyDefinitions/gammaLevel)

The gamma level for the image buffer.

[`static var horizontalDisparityAdjustment: CVAttachmentKeyDefinitionWithDefault<Self.ShouldPropagate, Int32>`](/documentation/CoreVideo/CVImageBufferAttachmentKeyDefinitions/horizontalDisparityAdjustment)

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

[`static var iccProfile: CVAttachmentKeyDefinition<Self.ShouldPropagate, Data>`](/documentation/CoreVideo/CVImageBufferAttachmentKeyDefinitions/iccProfile)

ICC color profile for the image buffer.

[`static var leftStereoDisplayMaskRectangle: CVAttachmentKeyDefinition<Self.ShouldPropagate, CVImageStereoDisplayMaskRectangle>`](/documentation/CoreVideo/CVImageBufferAttachmentKeyDefinitions/leftStereoDisplayMaskRectangle)

Specifies the rectangular display area within the left eye view of stereo images.

[`static var logTransferFunction: CVAttachmentKeyDefinition<Self.ShouldPropagate, CVImageLogTransferFunction>`](/documentation/CoreVideo/CVImageBufferAttachmentKeyDefinitions/logTransferFunction)

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

[`static var masteringDisplayColorVolume: CVAttachmentKeyDefinition<Self.ShouldPropagate, Data>`](/documentation/CoreVideo/CVImageBufferAttachmentKeyDefinitions/masteringDisplayColorVolume)

Mastering display color volume of the image.

[`static var pixelAspectRatio: CVAttachmentKeyDefinition<Self.ShouldPropagate, CVImagePixelAspectRatio>`](/documentation/CoreVideo/CVImageBufferAttachmentKeyDefinitions/pixelAspectRatio)

Pixel aspect ratio for the image buffer.

[`static var postDecodeProcessingFrameMetadata: CVAttachmentKeyDefinition<Self.ShouldPropagate, Data>`](/documentation/CoreVideo/CVImageBufferAttachmentKeyDefinitions/postDecodeProcessingFrameMetadata)

[`static var postDecodeProcessingSequenceMetadata: CVAttachmentKeyDefinition<Self.ShouldPropagate, Data>`](/documentation/CoreVideo/CVImageBufferAttachmentKeyDefinitions/postDecodeProcessingSequenceMetadata)

[`static var regionOfInterest: CVAttachmentKeyDefinition<Self.ShouldPropagate, CGRect>`](/documentation/CoreVideo/CVImageBufferAttachmentKeyDefinitions/regionOfInterest)

Specifies region of interest that image statistics cover.

[`static var rightStereoDisplayMaskRectangle: CVAttachmentKeyDefinition<Self.ShouldPropagate, CVImageStereoDisplayMaskRectangle>`](/documentation/CoreVideo/CVImageBufferAttachmentKeyDefinitions/rightStereoDisplayMaskRectangle)

Specifies the rectangular display area within the right eye view of stereo images.

[`static var sceneIllumination: CVAttachmentKeyDefinition<Self.ShouldPropagate, Int>`](/documentation/CoreVideo/CVImageBufferAttachmentKeyDefinitions/sceneIllumination)

Scene illumination measured in millilux.

[`static var transferFunction: CVAttachmentKeyDefinition<Self.ShouldPropagate, CVImageTransferFunction>`](/documentation/CoreVideo/CVImageBufferAttachmentKeyDefinitions/transferFunction)

The transfer characteristic for the image buffer.

[`static var yCbCrMatrix: CVAttachmentKeyDefinition<Self.ShouldPropagate, CVImageYCbCrMatrix>`](/documentation/CoreVideo/CVImageBufferAttachmentKeyDefinitions/yCbCrMatrix)

The matrix to convert from YCbCr to the RGB color space.

## Relationships

### Conforming Types

[`CVPixelBufferAttachmentKeyDefinitions`](/documentation/CoreVideo/CVPixelBufferAttachmentKeyDefinitions)

### Inherits From

[`CVAttachmentKeyDefinitions`](/documentation/CoreVideo/CVAttachmentKeyDefinitions)

---

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