New CG issue: Clarifying and simplifying EPUB Media Overlays (issue #83)

Hello Publishing CG,
My name is Heath Luke Sims. I’m a new participant in the Publishing Community Group and wanted to share a recently moved issue for broader discussion and feedback.
The issue is #83: Clarifying and simplifying EPUB Media Overlays
https://github.com/w3c/publishingcg/issues/83
The proposal focuses on two related goals:

  *
clarifying baseline, real-world expectations for EPUB Media Overlays as synchronized, pre-recorded narration (distinct from TTS); and
  *
exploring a constrained, interoperable Media Overlay profile, with an optional, simplified JSON serialization, to better reflect dominant read-aloud use cases and reduce tooling and implementation friction.

This work is intentionally exploratory and non-normative. It does not introduce a new media model, new APIs, or new rendering behavior, and it preserves full SMIL and existing EPUB conformance rules. The aim is to document and stabilize an interoperable baseline that reflects current practice and lowers the barrier to experimentation and feedback.
I would very much welcome input from publishers, reading system implementers, and tooling authors on whether the problem framing resonates, and on the feasibility or desirability of the proposed direction.
Thanks for your time, and I look forward to the discussion.
Best regards,

Heath Luke Sims