<cpn> scribenick: cpn
<kaz> minutes from the previous IG call
Mark: Thanks everyone. This is the
second meeting about the CTA WAVE programme
... Last month we gave an overview of the organisation, and focused on the content part of the spec.
... This month I'll talk about the HTML5 part of the effort.
... I'm not only co-chair of the M&E IG, but also the HTML5 API TF at CTA WAVE, and also co-chair of the Web Media API CG
... These two groups are really the same thing. It's the same
people doing the same work. The work is publicly visible, as with
other CGs.
... I'll describe the overall aspects, then the 3 specs we're
working on.
... The work sits between the MPEG world and W3C.
... There's the Content Spec TF, Device Playback Capabilities TF,
and HTML5 API TF.
... The overall goals are unifying media formats for HLS and DASH,
in the content spec.
<kaz> Mark's slides
Mark: The HTML5 group is
not advocating a world where all devices need to have HTML5,
... we're trying to unify HTML and CE platforms.
... There are three specs we're working on now.
... The first is the Web Media API spec. This is a spec and
associated tests to bring consistent HTML across devices.
... The next document is Web Media Application Developer
Guidelines, i.e., guidelines for how to make media web apps. This
is close to being finished.
... The other is an integrators spec, the Web Media User Agent
Integration spec.
... We're also working at W3C and WHATWG on gaps identified.
... There's a 100% overlap with the M&E IG, i.e., improving
support for media in HTML5.
... At the beginning, we considered doing this inside the IG, but
we can't write specs in the IG, hence creating a CG.
... This also allowed WAVE members to participate.
<kaz> Web Media API CG GitHub repo
<kaz> CG Report
Mark: The first published
version of the Web Media API Snapshot - this is a snapshot of APIs
that all devices should support.
... It was published in December 2017, and then at least once
annually, next in Q4 2018.
... There's a formal agreement between CTA and W3C to co-publish
the spec, as the W3C CG spec and the CTA spec.
... This way we're keeping CTA and W3C standards tied-in, to avoid
branching from W3C.
... We had a plan to move the CG spec to W3C standards track. We've
not done that yet, no urgency to do so.
... We're working with Fraunhofer Fokus to create a test suite
based on the W3C API tests.
... Every device should support the APIs, so the API tests are to
collect together the W3C tests, EME, MSE, other specs as listed in
the API snapshot.
... This will be made available freely and publicly.
... The changes to the snapshot and test suite will be
incremental.
... The browsers are four major code bases, three of which are open
source. CE devices typically use the open source codebases,
... but sometimes based on older versions, so out of date.
... The final spec is at the porting layer, where you take a
general purpose software stack, e.g., Webkit, and tie it to the
device.
... Considerations include mapping of keys on a remote device, all
aspects of hardware integration. This spec hasn't been released
yet.
... This is not an area generally addressed at W3C, but one we feel
is needed.
... Issues are open to the public, anyone can add and contribute.
... Dave Evans from BBC and myself are the co-editors of the Web Media API spec.
... All the specs listed in the Web Media API are supported by all four codebases.
... We'll have tests for each spec that will tell you if your
version is compatible. We're taking these specs and our tests will
be a subset of the W3C tests that run correctly on all 4
codebases.
... Currently, not all codebases pass all the tests. The only way
you won't pass is if you're running an old version of a
browser.
... It's not unusual for CE products to release with 3 or 4 year
old browsers, so we use this to encourage CE manufacturers to bring
their browsers up to date, and using the tests to do that.
<kaz> Web Media Application Developer Guidelines
Mark: Looking at the Web
Media Application Developer Guidelines, we have 3 editors. The
document talks about media playback use cases, content encoding
issues, web app structure and issues.
... Anyone making web apps using HTML5 video is encouraged to look
at this and file issues.
... Any comments are welcome now. The GitHub issues are public.
<kaz> Web Media User Agent Integration
Mark: The third spec, the
UA Integration spec. This is the link between the portable
codebases, eg., Chromium, and the underlying hardware.
... This is where we can find portability issues.
... Some example issues in the issue tracker. For example, key
codes, minimum graphics performance, UA string formatting, URL
length requirements.
... These are things which are either issues for portability or may
need testing. No final decision yet as to which of these are to be
included.
... What is really needed on this spec is additional editors. Jon
Piesing is on this, but he's not had time to write the whole spec.
Is someone in our community interested in signing up to work with
us?
Mark: So that's a summary of the CTA WAVE HTML5 API work. Any questions?
<kaz> scribenick: kaz
Chris: Is there any work on automation of the web platform tests for CE devices?
Mark: Good point. In addition to
taking the available W3C specs,
... and looking for which tests pass across the main browser
codebases,
... the RFP for the testing work included using smart TV and set
top box, picking 3 CE devices.
... We have had to make changes to the W3C Test Platform, giving
feedback for the test runner.
... We have very good representation from manufacturers at CTA WAVE
(shows WAVE Membership list),
... and contributions into W3C.
Chris: What's the criteria to select tests? As the WPT is continually updated, do you select a baseline set of browser versions to test against?
Mark: Yes, we have to pick a
version.
... The four main codebases are Google Chrome, Firefox, Webkit, MS
Edge.
... These tests can uncover porting issue as well.
... We run the test suite against some known version of the
browser, typically we'd choose a particular snapshot at Q4 in the
year
<Zakim> nigel, you wanted to ask if the tests only apply to APIs or also to conformant support of media formats
Nigel: Are these test about APIs only, or do they also cover support for media formats?
Mark: This is addressed more through
the Content Spec.
... The Content Spec TF extends MPEG CMAF spec,
... and the group also generates streams which are
conformant.
... The Device Playback Capabilities TF works on dynamic content
changes.
... I would encourage you to take a look what is done by the TF,
the specs are in draft.
Chris: About the HTML5 API spec, it would seem to have broader value than just CE TV devices, e.g., mobile. Any contact with mobile manufactures?
Mark: Absolutely, there are mobile
manufacturers in WAVE. The scope of what we're doing isn't just TV
and game consoles, it includes mobile devices and PCs too.
... (shows WAVE member list)
... The target devices will include any device that runs a modern
HTML user agent, including televisions, game machines, set-top
boxes, mobile devices and personal computers.
Chris: One final question. The
porting spec is interesting, I imagine this could uncover issues in
other specs,
... an example I've seen recently is work happening now to tighten
up the Document.cookie API, which may be underspecified right
now.
<cpn> -> https://github.com/whatwg/html/issues/804 and https://github.com/w3ctag/design-reviews/issues/290
Chris: I expect the porting spec could uncover similar such issues.
Mark: That's exactly how it is.
... We have an issue about explicitly requiring cookies, as the
cookie spec is optional.
https://github.com/w3c/webmediaporting/issues/6 issue 6
Mark: There is another issue we
found, a gap on the full-screen spec, which we reported to
WHATWG
... and had discussion with them.
https://github.com/w3c/webmediaapi/issues/22 issue 22
Chris: Thanks a lot for giving this presentation, Mark.
Chris: One final thing I
would like bring to people's attention is that there is now work
ongoing in WICG to update Media Source Extensions.
... I raised this on the IG's issue tracker, but now is a good time
to revisit the WAVE requirements around MSE.
https://github.com/w3c/media-and-entertainment/issues/6
Chris: Our next call will be on Tuesday, August 7th.
[adjourned]