You can access the Public CD for SMPTE RP428-22 in the GitHub repository.
Throughout the timeline of a D-Cinema composition, there can be periods where no Timed Text is present due to the editorial nature of the content and how a scene is being portrayed. For example, a scene that encompasses a long establishing shot with localised on-screen text. Localization best practices result in these localised instances being delivered as their own unique reel. Other examples may be an “insert” replacement shot, or a Rating and/or “Thank You” card at the start of a feature presentation.
D-Cinema manufacturing best practices, as defined in SMPTE RDD 52 – SMPTE Application Bv2.1, stipulates that should a D-Cinema track file be present for one reel, said tracks shall be present across all reels that comprise the composition, including Timed Text.
RP 428-22 specifies the best practice to adhere to when creating a D-Cinema XML file with no textual or image data that would cover the reels where no Timed Text data is present (effectively a “blank” Timed Text reel), ensuring compliance with the correct interpretation of ST 429-2 D-Cinema Operational Constraints. This is a practice which has not been previously disclosed to the industry outside of premier D-Cinema manufacturing vendors.
As of now, a Public Committee Draft is published on the SMPTE GitHub repository for industry review and feedback ending no earlier than 2022-02-01, and no later than 2022-06-01.