On May 19, Google unveiled something that many in the open source community had been expecting (and which the Free Software Foundation asked for in March): it made the VP8 video codec available to the public under a royalty-free, open source BSD-style license. Simultaneously, it introduced WebM, an HTML5-targeted open source audio-and-video delivery system using VP8, and announced a slew of corporate and open source WebM partners supporting the format, including web browsers and video sites such as its own YouTube property.

Dueling assessments, interested parties

The move was not unexpected. Google began trying to acquire VP8's creator, the codec shop On2, months ago, and speculation began even before the acquisition was final. The public reaction to the WebM launch was not unexpected, either. MPEG-LA, the commercial sellers of license for the competitor H.264 codec, suggested that anyone who used VP8 would get sued for patent infringement. An independent H.264 hacker quickly attacked VP8 as inferior on all technical counts, and surely in violation of multiple H.264 patents as well. H.264 proponents and general news sites began circulating that blog post, more so when Apple's Steve Jobs allegedly forwarded a link to it in response to an email asking his opinion on VP8.

Responses from the open source community itself have come in two flavors. The first was a long line of multimedia projects and companies announcing support for VP8 and WebM; some (like Mozilla and Collabora) were in the know before the deal was made public and working on their code, while others just reacted swiftly following the unveiling.

The second took on the opposition, rebutting both the MPEG-LA's public statements and the attacks of the H.264 hacker, Jason Garrett-Glaser. Many pointed out Garrett-Glaser's vested interest in H.264 being regarded as the technically best codec, given that he develops the x264 encoder project, and suggested that he was prejudiced against VP8 before even examining the release. StreamingMedia.com compared the codecs side-by-side, encoding the same source media at the same audio and video data rates, which Garrett-Glaser did not do, and concluded that there was no noticeable difference for most applications. Theora hacker Gregory Maxwell addressed the technical issues in an email to the Wikitech list, arguing that the initial release of Google's VP8 encoder represents a starting point ripe for optimization.

Other naysayers dismissed VP8 on the grounds that H.264 is already widely supported in hardware devices. That may be true, but most of this hardware support is in the form of embedded digital signal processor (DSP) code, and DSP ports of Theora were already in the works. Considering that Google has already funded ARM optimizations of Theora, there is grounds to believe it will push DSP playback of VP8 as well, and the company's Android platform is a likely place for it to make an appearance.

Patents and ambiguity

More important than the current (or even the potential-future) technical performance of VP8 is the question of whether it can legally be used under the terms spelled out in the WebM license and patent grant. It is clearly a technical improvement over Theora, but if the competition proved a genuine instance of patent infringement, the codec would need to be changed before it could be safely used.

On this point, again, there are two main threads of discussion. The first boils down to debate over the belief that VP8 must surely infringe on patents used in H.264 because the codecs share such a similar structure. Garrett-Glaser takes this stance, pointing out similarities in the algorithms. Xiph.org's Christopher "Monty" Montgomery dismissed that assessment as "serious hyperbole", and others in web article comment threads pointed out that all discrete cosine transform (DCT)-based codecs utilize the same basic steps; those steps are not what video codec patents cover.

Maxwell rebuffs the similarity argument as well, saying that Garrett-Glaser "has no particular expertise with patents, and even fairly little knowledge of the specific H.264 patents" due to the fact that x264 ignores them when implementing H.264 itself. He continued:

The second discussion thread amounts to divining whether H.264's patent licensor MPEG-LA will actually sue over a patent infringement charge against VP8. Here again, the public debate is dominated by assumptions: surely Google did a patent search that completely exonerated VP8; surely On2's patent lawyers knew what they were doing as they developed VP8 — and, alternatively, surely VP8 infringes somewhere, because there are just so many patents in H.264; surely VP8 infringes somewhere, because H.264 was created by the best codec authors using the best technologies.

To get out of the "surely" mire, consider the actual possibilities case by case. It is logical to suggest that if MPEG-LA has a genuine case, it will sue. If it does not have a genuine case, the question is whether the consortium will sue anyway to cause market confusion and buy time to continue selling H.264 patent licenses. But either way, the risks in filing a lawsuit are extraordinarily high — because Google could easily counter-sue.

Despite MPEG-LA's promotional material suggesting that blanket rights to use H.264 come with a license, the actual guarantee of the patent pool is quite weak:

Clarity, please

In other words, submarine patents and patent trolls can threaten H.264 — and in theory, On2 and Google may hold such patents. So what will MPEG-LA do? CEO Larry Horn already suggested, without directly claiming, that it believes it has a genuine case against VP8. Whether it does or doesn't, actually filing an infringement lawsuit could gamble away the H.264 cash cow. The far safer route is to make noise in public, pursue licensing deals with software and hardware vendors as long as possible, and work on the next codec licensing bundle. For its part, Google has done little in public other than express its confidence that there is no patent issue.

That sounds unsatisfying to the left-brained software developer, who would prefer a clear, bright line to be drawn with VP8 either on the "safe" or "unsafe" side. Unfortunately, the modern patent game does not work that way. In practice, patents are hidden weapons that can be used to sue (and threaten to sue) opponents. All commercial players hold them, and due to the vast number of patents granted — as well as the unknown reach of those patents — many are effectively hidden away until used in an attack.

Still, some have already suggested that Google can and should provide some level of increased clarity by publicly and transparently documenting the patents it now owns on VP8, and the patent search process it used to determine that nothing in VP8 infringed on a competitor's patents. Florian Mueller of FOSS Patents commented:

Rob Glidden, formerly of Sun, contrasted Google's one-shot announcement of VP8 with the process Sun used when working on the now-shuttered Open Media Stack video codec project, which "based their work on identifiable IPR [intellectual property rights] foundations, documented their patent strategy, and [was] willing to work with bona-fide standards groups to address and resolve IPR issues." By choosing to "go on their own", he added, Google actually undermines the open standards process the web relies on.

On the other hand, Google might consider it to be to its own advantage to keep the company's VP8 patent research secret, in order to force potential attackers to do more work looking for an infringement. No one does (nor should they) expect MPEG-LA to act with the clarity being asked of Google. At times MPEG-LA likes to present itself as if it is a standards body — one that produces technical work reflecting the consensus of industry, and ratifying the best possible ideas into global specifications. But that simply is not true. MPEG-LA is a for-profit business, selling its products and marketing them on behalf of its members and against all competitors.

Since its product is protection from a lawsuit by MPEG-LA itself, it gains nothing by drawing clear, bright lines. Even Horn's comment about creating a VP8 patent pool is couched in qualifiers and vague language: "there have been expressions of interest" and "we are looking into the prospects of doing so".

Of course, this is all really about HTML5 ... and money

Behind this entire fight is the availability of a free-to-implement video codec for HTML5. MPEG-LA and its pool members fought against Theora, and they will now do the same against VP8. Do not expect MPEG-LA to change its tune and support a completely free codec, ever; if it did the organization would have no reason to exist. MPEG-LA wants H.264 to win, not because it is better technically, but because it is their product.

Open source software is in a weird position in relation to MPEG-LA's licensing model. Even though it is the end users who infringe on the patents by watching H.264 content, the MPEG-LA requires anyone distributing codecs, like browser vendors, to pay for a license. That's just not possible for free software.

MPEG-LA has pushed back the date at which it will start charging royalty fees for streaming H.264 on the Internet until 2015, and even then there is a chance that they will push it back again. It does not explicitly care about the open source browser market itself; it has simply set up a fee structure that puts free software in an awkward position. The real money comes from video production and editing suites, and from large video hosting sites that transcode millions of videos.

Consequently, the real battle for VP8 adoption may be there as well. Google put out a long list of WebM-supporting partners when it unveiled the project, including several important proprietary software companies like creative-application-juggernaut Adobe and Quicktime's former star Sorenson. While MPEG-LA has more to lose than to gain by suing Google over VP8 today, that could change if these video production pipeline players start to shift over to WebM in a big way. If that happens, it might be the final straw which causes MPEG-LA to resort to the courtroom.