---
title: CMSampleBuffer.AttachmentKey
framework: coremedia
role: symbol
role_heading: Structure
path: coremedia/cmsamplebuffer/attachmentkey
---

# CMSampleBuffer.AttachmentKey

Keys that identify sample buffer attachments.

## Declaration

```swift
struct AttachmentKey
```

## Topics

### Attachment Keys

- [cameraIntrinsicMatrix](coremedia/cmsamplebuffer/attachmentkey/cameraintrinsicmatrix.md)
- [displayEmptyMediaImmediately](coremedia/cmsamplebuffer/attachmentkey/displayemptymediaimmediately.md)
- [drainAfterDecoding](coremedia/cmsamplebuffer/attachmentkey/drainafterdecoding.md)
- [droppedFrameReason](coremedia/cmsamplebuffer/attachmentkey/droppedframereason.md)
- [droppedFrameReasonInfo](coremedia/cmsamplebuffer/attachmentkey/droppedframereasoninfo.md)
- [emptyMedia](coremedia/cmsamplebuffer/attachmentkey/emptymedia.md)
- [endsPreviousSampleDuration](coremedia/cmsamplebuffer/attachmentkey/endsprevioussampleduration.md)
- [fillDiscontinuitiesWithSilence](coremedia/cmsamplebuffer/attachmentkey/filldiscontinuitieswithsilence.md)
- [forceKeyFrame](coremedia/cmsamplebuffer/attachmentkey/forcekeyframe.md)
- [gradualDecoderRefresh](coremedia/cmsamplebuffer/attachmentkey/gradualdecoderrefresh.md)
- [permanentEmptyMedia](coremedia/cmsamplebuffer/attachmentkey/permanentemptymedia.md)
- [postNotificationWhenConsumed](coremedia/cmsamplebuffer/attachmentkey/postnotificationwhenconsumed.md)
- [resetDecoderBeforeDecoding](coremedia/cmsamplebuffer/attachmentkey/resetdecoderbeforedecoding.md)
- [resumeOutput](coremedia/cmsamplebuffer/attachmentkey/resumeoutput.md)
- [reverse](coremedia/cmsamplebuffer/attachmentkey/reverse.md)
- [sampleReferenceByteOffset](coremedia/cmsamplebuffer/attachmentkey/samplereferencebyteoffset.md)
- [sampleReferenceURL](coremedia/cmsamplebuffer/attachmentkey/samplereferenceurl.md)
- [speedMultiplier](coremedia/cmsamplebuffer/attachmentkey/speedmultiplier.md)
- [stillImageLensStabilizationInfo](coremedia/cmsamplebuffer/attachmentkey/stillimagelensstabilizationinfo.md)
- [transitionID](coremedia/cmsamplebuffer/attachmentkey/transitionid.md)
- [trimDurationAtEnd](coremedia/cmsamplebuffer/attachmentkey/trimdurationatend.md)
- [trimDurationAtStart](coremedia/cmsamplebuffer/attachmentkey/trimdurationatstart.md)

## Relationships

### Conforms To

- [Equatable](swift/equatable.md)
- [Hashable](swift/hashable.md)
- [RawRepresentable](swift/rawrepresentable.md)
- [Sendable](swift/sendable.md)
- [SendableMetatype](swift/sendablemetatype.md)

## See Also

### Managing Attachments

- [sampleAttachments](coremedia/cmsamplebuffer/sampleattachments-swift.property.md)
- [CMSampleBuffer.SampleAttachmentsArray](coremedia/cmsamplebuffer/sampleattachmentsarray.md)
- [CMSampleBuffer.PerSampleAttachmentsDictionary](coremedia/cmsamplebuffer/persampleattachmentsdictionary.md)