Publishing WG Telco, 2017-09-18: SMIL Lite, metadata, fragment locators

See minutes online for a more detailed record of the discussions.


Marisa DeMeglio presented some work that the accessibility task force started on Media Overlay (MO)/Synchronized Multimedia (SMIL) related issues. The task force collected a number of use cases that shows that synchronized multimedia is an important feature for publishing. Use cases include text+sign language, or video+descriptive audio synchronization, for example.

The problem is that while SMIL has been implemented in several EPUB3 readers, its adoption on the Web is very poor. This is a source of problems for Web Publications. The question is how to move forward from there. One avenue is to explore the possibility to define a minimal SMIL (possibly transferring the syntax to JSON) and explore the avenue of creating, eg, polyfills for that level, with the goal of standardizing that level.

Administratively it is not clear whether that should happen within this WG (and whether that is possible, in terms of chartering) or whether a separate CG+WCIG+WG route at W3C is more preferable. To be explored.

Metadata section

A Pull Request has been proposed by Baldur Bjarnason et al on extra metadata issues. This proposal adds some (possibly optional) items to the information set, and also references to external metadata items in their own vocabularies. There has been some discussions on github already, and the resolution is to merge the pull request and separate some of the problems (also discussed on github) into separate github issues.

Fragment Locators

There is a separate discussion around a github issue on what formalism should be used for identifying fragments within resources, as a possibly alternative to EPUB CFI. One approach is to use the Web Annotation Selector and State Model, though this should be explored as for the usability and for its applicability.

The issue includes some questions on details that must be answered. It has been decided that the group would look at the WA document and the issue and a separate Pull Request would be provided.

About Ivan Herman

Ivan Herman is the Technical Lead for Publishing@W3C. For more details, see

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