Getting attachments from a CMSampleBufferRef object

Q:  I’m calling CMSampleBufferGetSampleAttachmentsArray(_:_:) in an attempt to get the kCMSampleBufferAttachmentKey_DroppedFrameReason from a CMSampleBufferRef, but the returned attachments array is always nil. What’s going on?

A: For getting attachments, the general rule is:

- for kCMSampleBufferAttachmentKey_*, use CMGetAttachment(_:_:_:)

- for kCMSampleAttachmentKey_*, use CMSampleBufferGetSampleAttachmentsArray(_:_:)

Therefore, to get the kCMSampleBufferAttachmentKey_DroppedFrameReason from a CMSampleBufferRef use CMGetAttachment(_:_:_:).

Document Revision History