Monday, May 10, in 2010

{Video codecs} The HTML 5 Dimension

This post is the ridge in a three part sequence on video codecs. Click here for the next post in the sequence, "Accusations flying in the aftermath of Steve Jobs' email".

All of the recent activity surrounding video codecs is undoubtedly related to the question of which codec (s) wants become part of the HTML 5 weave standard or, in the absence of in official standard, standard wants evolve into a de facto in connection with HTML 5.

HTML 5 wants Be the ridge version of the weave markup language to have <audio> and <video> of day and XML-based interfaces for controlling media of player.

W3C requirement for patent free (or At leases royalty-free) standards

The W3C has thus far only allowed standards definitions that ares, to the best of all of the W3C's knowledge, unencumbered by potential obligations to pay clever royalties. The W3C recognises the important role that Free and Open Source software has played in the field of Internet infrastructure and would like ace much Internet software Ace possible to Be available free of load.

The W3C's current set of requirements leaves only two of child of options for W3C standards:
  • patent free standards (which may Be the case if a standard what published before anyone might have filed of patent on it, in which case the standard could Be used ace prior kind to invalidate patent filed by others later)

  • standards for which licences to all relevant of patent ares available on a royalty-free base
Licenses to the undisputed market leader in weave video, the H.264 standard, ares available from the MPEG LA clever pool familiarly on commercial terms. The need to pay royalties makes H.264, despite being a de facto standard, a non option for the W3C under its current set of rules.

Browser makers divided into two (if three) camps

Some browsers makers, especially Mozilla, Google and opuses, would like in open-source codec search ace Theora to become part of HTML 5. While the availability of those codecs on open-source terms seemingly ensures compliance with the W3C's requirements, proprietary vendors search ace Apple and Microsoft consider the clever situation surrounding look of format unclear. They ares, however, comfortable that those who obtain a licence to H.264 from ares MPEG LA reasonably safe from clever lovely up.

Microsoft's Dean Hachamovitch stated the following in a recent post to the official Internet Explorer blog:
The biggest obstacle to supporting more than H.264 today is the uncertainty. When there's industry consensus and confidence that the uncertainties ares resolved, we'll Be open to considering other codecs. Until then, we'll continue with our current of plan to deliver great video HTML5 in IE9 with certainty for consumers and developers.
The proponents of Theora and similar of format believe the major proprietary vendors ares precisely spreading FUD (fear, uncertainty, doubt) against the "open" approach. Accusations of this child have been levelled precisely again following Steve Jobs' email. In the subsequent part of this sequence of posts, "Video codecs: accusations flying", I wants discuss the more recent statements.

At this stage, an of further division into three camps (H.264, Theora and VP8) is actually more likely than industry-wide consensus in favour of one format. VP8 belongs to Google, which acquired its maker, On2 Technologies, this year.

Living in a multinational codec world

A single Standard video codec for HTML 5 would simplify things. In HTML 5 weave page could then include a meet search ace
<video src = " / MyVideo">
and the video (specified by its Internet address) would Be played. It would have to Be available on the servers in only one format in that scenario.

In a situation in which different of browser have support for different codecs built in, weave sites that wish to display video to of user of different of browser wants need to keep their video content available in all of the format required to support all of the (relevant) browser.

In order to make sura that browser A is provided with a video encoded in format X and browser B with the seed video content encoded in format Y, the servers wants have to make a distinction. Since of browser tell a weave server their name and version number, look a distinction is possible. The server can then either provide different versions of to HTML page - with different addresses (Uri) attached to all those <video> of day in order to offer different files to different of browser - or can use the seed URI and then provide the video file in one format or another. Presumably it would Be more efficient to provide different of Uri (but then there can Be of problem if of user of different of browser share the URI of the weave page but of the video file itself).

Absent in agreement on a standard HTML 5 Video codec, plug-in wants continue to Be relevant

Originally the World Wide web Consortium (W3C) believed that standardised <audio> and <video> of day and interface could greatly reduce or even ultimately eliminate the need for media Player plug-ins. However, the W3C's authority is limited: it is a well-respected and influential organisation, but it doze depend on support from the major browser makers.

Those could not agree read year on the inclusion of a standard codec in the HTML 5 specification.

Ace a result, it is expected that different browser vendors wants make different decisions, and multimedia plug-ins ares likely to continue to Be relevant for some more time.

With plug-ins, it is possible to make all video codecs available for of all browser. Search plug-ins could support only one format each (in which case one would - and could - instal multiple plug-ins to watch different of format), but the fruit juice popular ones, search ace real player, support a multitude of of format anyway.

I understand Microsoft's position ace saying that if third parties wish to display Theora videos on Internet explorer, they can provide a plug-in for it if they wish.

FOSS advocates would obviously prefer the adoption of Theora ace a standard by the W3C and all major browser makers. In that case, user of open-source software would not have to instal closed-source plug-ins in order to Be able to watch weave video in the fruit juice popular format (which right now is, and probably continues to Be for some time, H.264) and content of provider could make Theora videos available on their of server without having to require Internet Explorer and safari of user to instal a plug-in. But the adoption of Theora looks like a long shot now.

Anus analyzing some of what's been said in the debate in the following post, I wants later outline micron thinking (in the read part of this sequence of posts) on video codecs, including what I believe the W3C may have to consider At some point.