YouTube is obviously a great site for video, but not for everyone as it contains various accessibility challenges, particularly keyboard access. The use of Flash itself to play the video can be problematic, not be mention requiring support of the Flash plugin. HTML5 is a pending solution (HTML5 video is available on YouTube as a “trial”), but in its infancy, HTML5 video has accessibility issues that still need to be resolved, as does HTML5 itself.
In the meantime, here are a few alternatives to the YouTube website which provide more accessible controls and a much cleaner interface.
If you still don’t have what you need or want, why not build your own interface?! The following are tools and resources for building more accessible YouTube videos including captioning:
Most of us are excited about HTML5 and all the benefits it will bring. Overly excited maybe is a more accurate term, which includes myself. We as a community need a “sanity check” about the readiness of HTML5 and its accessibility because:
The spec isn’t complete (2012 for Candidate Recommendation) thus requirements may still change.
The browsers are in the middle of implementation and much accessibility support isn’t provided yet.
There are many accessibility issues remaining such as Canvas in general; no semantic information to assistive technology for many elements; keyboard access lacking in audio & video controls in most conditions.
The web site HTML5Accessibility.com is a great place to learn about these issues for each major web browser. Along with that is a presentation by Steve Faulkner (@stevefaulkner) of the Paciello Group: HTML5 Accessibility – Is It Ready Yet? presentation by Steve Faulkner and and Hans Hillen (SlideShare).
Because of this intermediate stage, we developers must implement more complex code as desired, including fallback methods for user agents which don’t yet support the HTML5 features. Here are some great resources on doing so:
HTML5 Cross browser Polyfills – Shims, fallbacks, and polyfills in order to implant html5 functionality in browsers that don’t natively support them.
As you probably know, HTML5 provides a video tag for rendering a video natively in a web browser (and audio as well). But unfortunately, as of now, HTML5 video isn’t very accessible, yet.
Controls
Browser support for native HTML5 video controls varies widely. No browsers but Opera provide keyboard-accessible controls. Well, you can also start/stop with keyboard in Firefox 3.6. To make the controls keyboard-accessible calls for JavaScript. This is fairly easy to do, and is quite fun to implement for web geeks like me. But nonetheless it requires JavaScript which obviously isn’t good for devices and browsers which don’t have JavaScript available.
Note that in Firefox 3.6 and below, disabling JavaScript also disables the native video controls! To bring up a contextual menu, you must do a mouse right-click in the video.
Captions
The HTML5 spec has a great plan for captions, timed tracks. It accommodates well for different types of roles (captions, subtitles, descriptions) and multiple languages. The format of the caption text files themselves may be similar to the time stamp format WebSRT (Web Subtitle Resource Tracks). Sadly, there is no support for timed tracks in any browser at this time. The code would go inside the video tag and would look something like this:
Fortunately, in the meantime, Bruce Lawson of Opera provides a method for JavaScript HTML5 video captions. The solution uses JavaScript to grab caption text from span tags with time attributes and place the text over a video. Neat! If JavaScript is unavailable, the caption text appears below the video.
About the Codecs/Containers
Not directly related to accessibility, but let’s take a look at the supported video codec/containers of the major browsers. First off, and not surprisingly, Internet Explorer doesn’t support any HTML5 video. And the word is that IE9 will only support WebM if it’s installed on the operating system.
So to cover all major browsers today, you’ll need to encode to an OGG and MP4 file, and then do a Flash video fall-back for IE. Here’s a great table on current support codecs/containers.
Video support in shipping browsers
Codecs/container
IE
Firefox
Safari
Chrome
Opera
iPhone
Android
Theora+Vorbis+Ogg
·
3.5+
·
5.0+
10.5+
·
·
H.264+AAC+MP4
·
·
3.0+
5.0+
·
3.0+
2.0+
WebM
9*
4
·
5.0+
10.6+
·
·
It appears WebM will be the codec of the future, but again, it is only partially supported at this time.
HTML5 is hot. It’s new, powerful, and exciting. But what is it exactly, and how will it make the web more accessible? Dennis discusses these issues and more with web accessibility veteran John Foliot. Topics include background on HTML5, browser support, new form functionality, how Canvas can be accessible, and much more!
