Although the HTML5 spec won't be finalized until July 2014, the W3C (World Wide Web Consortium), has scheduled its "last call" for feature-completeness for this May. So what's missing?
According to the editor of the specification, refinement of the HTML5's multimedia capability is the only outstanding issue to be resolved before the W3C can move to the final stage of the HTML5 specification effort: finalizing the technical specs, getting final comments, and creating test suites to validate interoperability across browsers and other technologies, said Ian Jacobs, head of W3C communications. That last stage will take about three years.
The multimedia holes in the HTML5 spec
The primary aspect of multimedia capability to be resolved this spring is multitracking for audio and video, though the W3C isn't committing to having this capability in the final HTML5 spec. Multitracking would, for example, enable a choice of spoken languages to accompany a video, allow the presentation of a video within another video, and permit applications like chat rooms to display simultaneous audio from multiple people.
Also possible to be added to the HTML5 spec after the "last call" are extensions to the canvas 2D technology and the ability to mark up photo credits, said HTML5 specification editor Ian Hickson. He expects such additions to first come up in the WHATWG (Web Hypertext Application Technology Working Group) HTML5 proposals, then migrate to the W3C effort through the W3C HTML working group chairmen. (The two organizations are collaborating on the HTML5 spec.)
One technology not slated for HTML5 is a standard video codec. Developers of the specification have been unable to find a satisfactory open source codec to use, so they are leaving each browser maker to choose its own codec and instead providing standard APIs for them to use in HTML5. "That's pretty much the deal," Hickson said. "HTML5 doesn't care what the codecs are," Jacobs added.
The lack of a video codec does not have to be resolved for HTML5 to be completed, said Forrester Research analyst Jeffrey Hammond. "It's a pain for developers, but [they] can work around it for the time being" by encoding in multiple formats, he said.
WebSocket, developer tools not yet HTML5-ready
HTML5 has been paired with complementary specifications, such as CSS (Cascading Style Sheets) 3 and WebSocket, for two-way Web communications, in an effort to promote an "open Web." HTML5 is in pretty good shape in terms of the language, but WebSocket capabilities are needed for applications like stock trading and real-time data feeds, Hammond said. "You can do that fine with Flash or Java," but not with HTML5, he said. There's also a security issue: WebSocket implementations have been pulled from current browsers because of concerns over potential screen hijacking, he said.
HTML5's newest target date could slip again
The July 2014 deadline for the final HTML5 standard is not set in stone, Hickson noted. He pointed out that in 2007, the W3C projected a final specification would arrive in 2010, which did not happen.
That lack of certainty may explain why Jacobs is championing use of HTML5 as it is right now. "We're telling people to use it already," he said. "The goal is to get feedback to improve interoperability," he added. That advice contradicts what Philippe Le Hegaret, the W3C interaction domain leader, said last fall, when he cautioned against deploying HTML5 in websites at the time because of the incompleteness of the specification.