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# CMSampleBuffer.AttachmentKey

Keys that identify sample buffer attachments.

```
struct AttachmentKey
```

## Topics

### Attachment Keys

[`static let cameraIntrinsicMatrix: CMSampleBuffer.AttachmentKey`](/documentation/CoreMedia/CMSampleBuffer/AttachmentKey/cameraIntrinsicMatrix)

[`static let displayEmptyMediaImmediately: CMSampleBuffer.AttachmentKey`](/documentation/CoreMedia/CMSampleBuffer/AttachmentKey/displayEmptyMediaImmediately)

[`static let drainAfterDecoding: CMSampleBuffer.AttachmentKey`](/documentation/CoreMedia/CMSampleBuffer/AttachmentKey/drainAfterDecoding)

[`static let droppedFrameReason: CMSampleBuffer.AttachmentKey`](/documentation/CoreMedia/CMSampleBuffer/AttachmentKey/droppedFrameReason)

[`static let droppedFrameReasonInfo: CMSampleBuffer.AttachmentKey`](/documentation/CoreMedia/CMSampleBuffer/AttachmentKey/droppedFrameReasonInfo)

[`static let emptyMedia: CMSampleBuffer.AttachmentKey`](/documentation/CoreMedia/CMSampleBuffer/AttachmentKey/emptyMedia)

[`static let endsPreviousSampleDuration: CMSampleBuffer.AttachmentKey`](/documentation/CoreMedia/CMSampleBuffer/AttachmentKey/endsPreviousSampleDuration)

[`static let fillDiscontinuitiesWithSilence: CMSampleBuffer.AttachmentKey`](/documentation/CoreMedia/CMSampleBuffer/AttachmentKey/fillDiscontinuitiesWithSilence)

[`static let forceKeyFrame: CMSampleBuffer.AttachmentKey`](/documentation/CoreMedia/CMSampleBuffer/AttachmentKey/forceKeyFrame)

[`static let gradualDecoderRefresh: CMSampleBuffer.AttachmentKey`](/documentation/CoreMedia/CMSampleBuffer/AttachmentKey/gradualDecoderRefresh)

[`static let permanentEmptyMedia: CMSampleBuffer.AttachmentKey`](/documentation/CoreMedia/CMSampleBuffer/AttachmentKey/permanentEmptyMedia)

[`static let postNotificationWhenConsumed: CMSampleBuffer.AttachmentKey`](/documentation/CoreMedia/CMSampleBuffer/AttachmentKey/postNotificationWhenConsumed)

[`static let resetDecoderBeforeDecoding: CMSampleBuffer.AttachmentKey`](/documentation/CoreMedia/CMSampleBuffer/AttachmentKey/resetDecoderBeforeDecoding)

[`static let resumeOutput: CMSampleBuffer.AttachmentKey`](/documentation/CoreMedia/CMSampleBuffer/AttachmentKey/resumeOutput)

[`static let reverse: CMSampleBuffer.AttachmentKey`](/documentation/CoreMedia/CMSampleBuffer/AttachmentKey/reverse)

[`static let sampleReferenceByteOffset: CMSampleBuffer.AttachmentKey`](/documentation/CoreMedia/CMSampleBuffer/AttachmentKey/sampleReferenceByteOffset)

[`static let sampleReferenceURL: CMSampleBuffer.AttachmentKey`](/documentation/CoreMedia/CMSampleBuffer/AttachmentKey/sampleReferenceURL)

[`static let speedMultiplier: CMSampleBuffer.AttachmentKey`](/documentation/CoreMedia/CMSampleBuffer/AttachmentKey/speedMultiplier)

[`static let stillImageLensStabilizationInfo: CMSampleBuffer.AttachmentKey`](/documentation/CoreMedia/CMSampleBuffer/AttachmentKey/stillImageLensStabilizationInfo)

[`static let transitionID: CMSampleBuffer.AttachmentKey`](/documentation/CoreMedia/CMSampleBuffer/AttachmentKey/transitionID)

[`static let trimDurationAtEnd: CMSampleBuffer.AttachmentKey`](/documentation/CoreMedia/CMSampleBuffer/AttachmentKey/trimDurationAtEnd)

[`static let trimDurationAtStart: CMSampleBuffer.AttachmentKey`](/documentation/CoreMedia/CMSampleBuffer/AttachmentKey/trimDurationAtStart)

## Relationships

### Conforms To

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

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

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

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

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

---

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