As prematurely announced yesterday, the standard for e-books, ePub, is out in a new draft version this morning. It will be final in May (2011) at BEA, a very fast pace. It has many additional elements borrowed from HTML5 technologies. More details here after I read it :)
Okay, after a quick perusal, some things jump out:
- Rather than embracing CSS3, the standard calls for CSS 2.1 (with added modules from CSS3). This means a subset of the newer selectors and attributes, sigh. Media queries are supported (a way for pages to “ask” about the reader’s capabilities, orientation and size), as are fun things like columns, embedded fonts, and headers/footers.
- Several bits provide for the synchronization of text and audio.
Bob Kasher says ePub helped Apple get into the market for e-books. Hm.
Highlights for Robert of ePub3:
- ePubs in any language, any kind of script/glyphs/writing direction, vertical etc.
- Audio and video
- Accessibility built in
- Stronger metadata to enable ePubs to be findable and indexable
- Navigation variations (replacing <guide> with <landmarks>), nav for mobile phones
- Print support
ePub3 will be standard package for distributing accessible content, replacing the DAISY standards.
We’re basing the standard on HTML5; all the publishing processes can be based on HTML5 and will be directly usable in ePub3.
On the metadata side:
- ePub3 is designed to be backwards compatible with v2.
- Introducing new optional metadata elements
- Multiple elements allowed for titles, for ordering, languages
- Built on Dublin Core and a subset of RDF-A 1.1 (yuck)
- Manifest can get much more specific to communicate to device the kinds of content used: illustrations, math markup, audio/video
- Should work well for newspapers, magazines
Still three containers
- Package (ZIP)
- Content (HTML5)
- Description (metadata files)
But completely rewritten to be easier to be human-readable.
Audio and video can be embeddable in an open-standards way similar to HTML5 (using openly available video encoding standards). Graphic novels can be represented with Structured Vector Graphics.
Scripting via ECMA script for interactivity is now fine (used to be “discouraged”). For example, a footnote can be done with a popup instead of link to another part of a book.
Question about other web content management systems like Drupal; what is relationship between these and ePub? WordPress has been furthest along in integrating with ePub. ePub does not require content to be downloaded, it can be browsed via a browser just fine.
Video spec: H.264 (a way of encoding video that’s free to use, but not public domain) is video standard *right now*, but there is a big fight about what the open standard will be. By end of this year, that may change to another encoding. Might change to WebM, which is royalty-free.
In May, will take a ‘snapshot’ of where specification of HTML5 is, and use that as the markup part of ePub3 final specification. Any documents that validate as ePub3 will be valid HTML5.
The stylesheet specification is CSS 2.1 (BOO).
The ePub working group “expects” that people will use ePub3 as a way to store content, instead of other basic formats (like XML, DOC, etc.).
There is a proposal to specify a way for ePubs to link between themselves, but needs more support to become part of the final spec.