Dean Hachamovitch, corporate vice president for Internet Explorer, today announced the launch of a plug-in for Google's Chrome Web browser that reinstates support for the H.264 video codec when used with HTML5's <video> tag. The plug-in will enable Chrome users on Windows 7 to view H.264 video, even though Google announced the decision to remove native support for the codec last month.

This decision mirrors the company's release last December of an equivalent Firefox plug-in.

The reason Microsoft gives for creating these plug-ins is that since the underlying operating system includes native support for the codec in question, users should be empowered to view videos that use the codec—and that's regardless of their browser preference. The intent is to be pragmatic: most users are indifferent to the ideological or other reasons that surround video codecs and software patents; they just want to watch some video. If the operating system can ensure that the browser vendor's choices don't stand in the way of watching that video, Microsoft believes the operating system should fill the gap: the Firefox and Chrome plug-ins are the company's way of doing just that.

The company is also working to ensure that WebM HTML video will play back in Internet Explorer. Google is developing plug-ins of its own to provide WebM support to Windows and Internet Explorer 9, and Microsoft has worked with Google to help ensure the plug-ins work properly.

Serious concerns

What Microsoft isn't doing is developing or bundling a WebM plug-in itself. While announcing the plug-in, the company also outlined a number of questions and concerns it has regarding WebM: who bears the liability for any intellectual property risk associated with the codec, how will Google allow genuinely open engagement, and what the plan is to achieve the kind of consistent, widespread support that H.264 offers.

The first of these concerns is perhaps the most substantial: though Google insists that WebM is "open"—the company says that it owns all the necessary patents that cover the VP8 video codec, and that these patents are available on a royalty-free basis—assertions of "openness" count for little if a company makes a claim of patent infringement. Google offers no indemnification for costs incurred in such a lawsuit, meaning that anyone using, implementing, or distributing VP8 could be at risk (this is in contrast to Microsoft, which does offer users of its products indemnification against patent lawsuits).

WebM's supporters often point out that there have been no WebM lawsuits yet, as if this meant the codec was free of risk. Such claims ignore the practical realities of patent lawsuits. The JPEG image compression format was standardized in 1992. It was not until a decade later that a company first claimed that the format infringed on patented technology: between 2002 and 2005, when its patent was eventually invalidated, Forgent Networks sued more than 30 companies for patent infringement, and received more than $100 million for licensing the patent to another 30 companies. A second round of lawsuits was initiated in 2007 by Global Patent Holdings; its patent too was invalidated, in 2008.

Though the patents driving these lawsuits were both ultimately deemed to be invalid due to existing prior art, they were costly and time-consuming to defend against. And, importantly, they took a long time to emerge. That nobody has sued Google yet does not mean that VP8 does not infringe any patents; it simply means that nobody has sued Google yet. Nor, if the history of JPEG and GIF is anything to go by, are they likely to sue Google any time soon. History shows that the preferred technique is to wait until a technology is in wide use, and then sue many people for infringement, whether they are developers, distributors, or end-users. We wouldn't expect to see a lawsuit at this early stage; it would scare people off the format altogether, thereby reducing the likelihood of lucrative licensing deals and/or settlements.

Microsoft says that until the situation around intellectual property and liability is clear then it will remain agnostic towards the choice of codec. Internet Explorer 9 supports H.264 because Windows supports H.264; it will similarly support WebM with a suitable Windows plug-in. H.264 does open up the company to some risk, but it believes that this is a necessary risk (given the importance of H.264 support for things like TV and optical disc playback) and a small risk (given that many of the companies with relevant intellectual property have disclosed their patents already).

The company's own history in this area—many patent holders emerged from the woodwork when SMPTE worked to standardize WMV as VC-1—has led it to be cautious when it comes to WebM, but Microsoft recognizes that there is value in a codec that is well-protected against legal issues: H.264 appears to be that codec at the moment, but WebM could achieve that status with some help from Google.

The implication in the post is that if Google were to, say, indemnify developers and users of WebM, then Microsoft would be willing to take advantage of that indemnification by developing and/or distributing WebM support itself. Such a move would certainly enhance WebM's reach, but the ball is in Google's court.

The other concerns appear less important: it seems that Microsoft would prefer for WebM to be governed by a genuine standards body (rather than merely submitting a nonauthoritative document to IETF), and would like a better plan for how to give WebM the kind of ubiquity that H.264 enjoys. These are reasonable concerns, and certainly areas of improvement for Google, but are secondary to the patent liability question: only patent liability has the potential to inflict enormous costs on anyone using WebM. As long as Google fails to address them seriously, browser plug-ins and competition from H.264 are likely to remain a feature of HTML5 video.