Google’s challenges of freeing VP8

Since On2 Technology’s stockholders have approved the merger with Google, there are now first requests to Google to open up VP8.

I am sure Google is thinking about it. But … what does “it” mean?

Freeing VP8
Simply open sourcing it and making it available under a free license doesn’t help. That just provides open source code for a codec where relevant patents are held by a commercial entity and any other entity using it would still need to be afraid of using that technology, even if it’s use is free.

So, Google has to make the patents that relate to VP8 available under an irrevocable, royalty-free license for the VP8 open source base, but also for any independent implementations of VP8. This at least guarantees to any commercial entity that Google will not pursue them over VP8 related patents.

Now, this doesn’t mean that there are no submarine or unknown patents that VP8 infringes on. So, Google needs to also undertake an intensive patent search on VP8 to be able to at least convince themselves that their technology is not infringing on anyone else’s. For others to gain that confidence, Google would then further have to indemnify anyone who is making use of VP8 for any potential patent infringement.

I believe – from what I have seen in the discussions at the W3C – it would only be that last step that will make companies such as Apple have the confidence to adopt a “free” codec.

An alternative to providing indemnification is the standardisation of VP8 through an accepted video standardisation body. That would probably need to be ISO/MPEG or SMPTE, because that’s where other video standards have emerged and there are a sufficient number of video codec patent holders involved that a royalty-free publication of the standard will hold a sufficient number of patent holders “under control”. However, such a standardisation process takes a long time. For HTML5, it may be too late.

Technology Challenges
Also, let’s not forget that VP8 is just a video codec. A video codec alone does not encode a video. There is a need for an audio codec and a encapsulation format. In the interest of staying all open, Google would need to pick Vorbis as the audio codec to go with VP8. Then there would be the need to put Vorbis and VP8 in a container together – this could be Ogg or MPEG or QuickTime’s MOOV. So, apart from all the legal challenges, there are also technology challenges that need to be mastered.

It’s not simple to introduce a “free codec” and it will take time!

Google and Theora
There is actually something that Google should do before they start on the path of making VP8 available “for free”: They should formulate a new license agreement with Xiph (and the world) over VP3 and Theora. Right now, the existing license that was provided by On2 Technologies to Theora (link is to an early version of On2′s open source license of VP3) was only for the codebase of VP3 and any modifications of it, but doesn’t in an obvious way apply to an independent re-implementations of VP3/Theora. The new agreement between Google and Xiph should be about the patents and not about the source code. (UPDATE: The actual agreement with Xiph apparently also covers re-implementations – see comments below.)

That would put Theora in a better position to be universally acceptable as a baseline codec for HTML5. It would allow, e.g. Apple to make their own implementation of Theora – which is probably what they would want for ipods and iphones. Since Firefox, Chrome, and Opera already support Ogg Theora in their browsers using the on2 licensed codebase, they must have decided that the risk of submarine patents is low. So, presumably, Apple can come to the same conclusion.

Free codecs roadmap
I see this as the easiest path towards getting a universally acceptable free codec. Over time then, as VP8 develops into a free codec, it could become the successor of Theora on a path to higher quality video. And later still, when the Internet will handle large resolution video, we can move on to the BBC’s Dirac/VC2 codec. It’s where the future is. The present is more likely here and now in Theora.


ADDITION:
Please note the comments from Monty from Xiph and from Dan, ex-On2, about the intent that VP3 was to be completely put into the hands of the community. Also, Monty notes that in order to implement VP3, you do not actually need any On2 patents. So, there is probably not a need for Google to refresh that commitment. Though it might be good to reconfirm that commitment.


ADDITION 10th April 2010:
Today, it was announced that Google put their weight behind the Theorarm implementation by helping to make it BSD and thus enabling it to be merged with Theora trunk. They also confirm on their blog post that Theora is “really, honestly, genuinely, 100% free”. Even though this is not a legal statement, it is good that Google has confirmed this.