At W3C Technical Plenary in Lyon
Written by Joshue O Connor Monday, 08 November 2010
I just attended the W3C Technical Plenary meeting last week in Lyon France. I was there as a member of the HTML5 Working Group, the HTML5 Bug Triage SubTeam and the Protocols and Formats Working Group - so I was there for meetings and discussions relating largely to accessibility issues within these groups. There are over 70 working groups in the W3C.
It was a rather quiet TPAC this year, with seemingly little dissent or disagreement, on the surface anyway. At the main Tech plenary day on Weds there was a frisson of excitement when Tim Berners-Lee was rather critical of HTML5 relaxing its syntax rules (which I missed but there was some discussion after). Many of the group meetings were rather agreeable also, and there were some productive outcomes relating to furthering accessibility in HTML5.
Topics that were discussed ranged from Media Accessibility, incorporating Copyright Metadata in Video, ARIA and API mappings, Canvas Accessibility, future challenges for accessibility, Epub (HTML5 and the publishing industry), as well as advances in CSS such as use of @fontface (@fontface isn't really new), WOFF and animations using CSS3 transitions of which there are lots of examples online, some groovy, some less so.
There has also been some criticism about the power and influence that browser manufacturers have at the event, but this is the Web and for most people the browser is the Web, so I guess this dominance is a natural byproduct of this relationship.
Alternate Text for Images in HTML 5
A hot topic, or to be more accurate a hot topic that has morphed into a rather long ongoing debate - is text alternatives in HTML5. There are several change proposals to the current spec that were discussed and a draft document that was put together by several working group members (including yours truly) on advice and guidance for authors using alternatve text in HTML5.
There is a general consensus that this guidance should be outside of the HTML5 spec itself, so this is an example of how guidance can be normatively referenced outside the specification itself. There are several change proposals before the group at the moment, and we hope to distill them, narrow down the options and soon resolve this issue, which is like I say, ongoing.
Media Accessibility
This issue is a hot topic. Exactly how will HTML5 handle and display rich media like Video? This is yet to be decided. There is still no official container/codec for HTML5. There are many options from MPEG4, to Ogg, WebM. Flash Video is a proprietary solution for video that currently is in wide use via its ubiquitous plugin, but it is still not native to the browser and we (sic) are currently in the middle of a video format war with Apple, Adobe and Google amongst others, to decide exactly how you will consume your video content in the future. Flash may soon be a thing of the past, or at least certainly lose its current dominance as the main video platform for the web. The three most relevant codecs for HTML5 today are H.264, Theora, and VP8.
So why is this an issue for accessibility? Well, as just outlined a container format has the various tracks etc that are used to sync the video and audio files that make your viewing experience happen. However, there is also other data which will allow the time-line of the video to be marked so meta data such as captioning, subtitling and audio description can be attached, accessed and displayed as needed by the user. This information is very important to users with sensory disabilities and can be held within the aforementioned containers.
There is also the issue of copyright information which on first glance may not seem related to accessibility. However, if you are a creator of online content in a university you may be obliged to make your content accessible to your students and this kind of important information can also be embedded as meta data within the container, and clearly outline what your responsibilities are and/or any copyright limitations that may apply to the creation of transcripts, captions or other usage limitations etc. More information can be found on the HTML5 Accessible Media Wiki.
Canvas Accessibility
The Canvas API is, when combined with JavaScript, a way of painting pixels directly onto the screen to create rich media graphics and games. There are some very interesting and colourful examples online of the Canvas element in use. In terms of accessibility however it has a lot of potential problems because it has no DOM, no system caret, limited primitives and basically accessibility has to be completely bolted on!
What's the problem you may say? The HTML 5 spec is full of many useful elements and tools that allow developers to build accessible stuff that they could do without Canvas (indeed the spec recommends that when there are alternatives Canvas should not be used). The problem is that what developers will do with the toolkits they have just cannot be anticipated. They naturally like to build unpredictable things, and push the envelop, with is great and completely understandable. Therefore, it is necessary to try to make the Canvas element more accessible to people with disabilities to try and reduce potential problems down the line, such as those illustrated with the Mozilla Bespin editor.
There have been various proposals to 'bolt on' accessibility (which in itself is not desirable as the element should natively support it, but in truth this is by design as the use for the Canvas element is primarily visual. It is also very light and fast in terms of rendering), such a Shadow DOM, the accessibility DOM (aDOM) or expanding on the DOM concept with ARIA and support for Platform Accessibility APIs.
For more on the Canvas accessibility issue see the WebAIM website for some history, and for a much more detailed view on Canvas see the HTML 5 WG wiki on Canvas Element Accessibility Issues.
Epub and HTML5
Epub is an electronic publishing standard used by the International Digital Publishing Forum for electronic books used for reflowable content. This allows a book to be viewed on various portable devices for example. It currently uses XHTML/CSS for rendering the book and other standards to store metadata. Epub may be moving towards using HTML5 and CSS3. HTML5 provides a greater set of functions to be used in E-Books such as the Video element for example. Epub is used currently by Apple iBooks, Sony Reader, DAISY and others.
Our digital Identities
Another hot topic was our 'digital identities'. How can we keep them safe, what are the future use cases for our online profiles? Regarding the safety of our online identities, this is a very important issue and there was a demonstration at the Weds meeting of a plugin for Firefox that can be very easily used to not only see what username/password combinations are being sent over an open wifi network, but also how easy it is to adopt another persons digital identify and then log into their Twitter account, and lock them out by changing the password and then assuming their identify.
The potential for this kind of thing to cause chaos is rather alarming. Note, that these demonstrations were for platforms that use the insecure http:// and not the more secure https:// which is used by your online banking etc so don't worry too much! The point is, that there are serious issues underlying the architecture of the web that many people are not aware of. Session hijacking is nothing new, it has just gotten easier.
Currently we are in the very early days of adapting to the use of an online digital identity, this is usually in the form of a Facebook page, use of Twitter, LinkedIn and many others. For many this is a diversion, some fun, a way of staying in touch with friends. However, what if that profile was used as a more substantial form of identity to provide you with access to government services, or as a method of validating your identity in the real world as a form of passport? The potential for this is huge, as people are voluntarily revealing vast amounts of personal data, the issue of first exactly what your digital identity is, what it represents, and secondly what it can be used for are two very big questions.
Just a flavour..
So there is a flavour of some of the issues and hot topics that I encountered at TPAC. It was as always, an informative and enjoyable conference where I met old friends and made some new ones.