Carriage of ID3 Timed Metadata
HTTP Live Streaming (HLS) supports the inclusion of timed metadata in ID3 format in various container formats, as described in TM-HLS.
A large ecosystem has built up around carrying timed ID3 metadata in HLS for applications such as ad delivery & audience measurement. There are many benefits to adopting CMAF for HLS media delivery, but without a specification for carrying ID3 as sparse timed metadata in CMAF, deployment by companies in this ecosystem is blocked.
This specification describes how such ID3 metadata can be carried as timed metadata in a CMAF-compatible fragmented MP4 (fMP4) stream as used by the HLS protocol.
CMAF-compatible fragmented MP4 can also be used in DASH. The elements defined in this specification may also be used with DASH.