Type	Topic	Plugin	Version	macOS	Windows	Linux	iOS	Targets
class	AVFoundation	MBS AVFoundation Plugin	13.2	✅ Yes	❌ No	❌ No	✅ Yes	All

CMSampleBuffers are CF objects containing zero or more compressed (or uncompressed) samples of a particular media type (audio, video, muxed, etc), that are used to move media sample data through the media system.

A CMSampleBuffer can contain a CMBlockBuffer of one or more media samples or a CVImageBuffer, a reference to the format description for the stream of CMSampleBuffers, size and timing information for each of the contained media samples, and both buffer-level and sample-level attachments. The buffer-level attachments of a CMSampleBuffer are distinct from the attachments of its contained CMBlockBuffer. An example of a sample-level attachment is an annotation about video frame dependencies (eg. "droppable", "other frames depend on me", "I depend on other frames", etc). Each sample (video frame) in the CMSampleBuffer would need its own attachment in this case. Another sample-level attachment example is SMPTE timecode acquired during capture. To get and set a CMSampleBuffer's buffer-level attachments, use the APIs in in CMAttachmentBearer.h (CMGetAttachment et al).
It is possible for a CMSampleBuffer to describe samples it does not yet contain. For example, some media services may have access to sample size, timing and format information before the data is read. Such services may create CMSampleBuffers with that information and insert them into queues early, and attach (or fill) the CMBlockBuffers of media data later, when the data becomes ready. To this end, CMSampleBuffers have the concept of data-readiness, which can be tested, set, forced to become ready "now", etc. It is also possible for a CMSampleBuffer to contain nothing but a special buffer-level attachment that describes a media stream event (eg. "discontinuity: drain and reset decoder before processing the next CMSampleBuffer"). Such a special attachment can also be attached to regular CMSampleBuffers (ie. that contain media sample data), and if so, the event it describes is defined to occur after the samples in that CMSampleBuffer.

The MBS Plugin implements a subset of what's available. If you need more, please do not hesitate to contact us.
This is an abstract class. You can't create an instance, but you can get one from various plugin functions.