If you’re ever deciding between On2 VP6 and H.264, then here is info on how the BBC went about it.
I micro-blogged this earlier today on Twitter, but want to call out some main topics in the weblog.
An intro to video delivery choices:
The video you see in BBC iPlayer today is encoded using the On2 VP6 codec, at a bitrate of 500Kbps. The On2 codec (a video compression technology from a company called On2) is pretty much the standard for video delivery over the internet today. It’s optimised for moderately low data rates (300Kbps to 700Kbps, rather than the 2Mbps to 4Mbps needed for HD content), and low CPU usage, allowing it to work reasonably well on older computers. In short, On2 VP6 is the video workhorse of the internet.
… Compared to On2 VP6, H.264 delivers sharper video quality at a lower data rate, but requires more CPU power to decode, particularly on older machines, and the user needs to have the latest version of Flash installed.
Back in December of last year, relatively few people had installed the Flash player needed to play H.264 content; now almost 80% of BBC iPlayer users have it. More machines now have graphics cards with H.264 hardware acceleration. Additionally, Level3, a content distribution network (CDN) is now able to stream H.264 content to ISPs in the UK, and the content encoding workflows that we use (Anystream and Telestream) are now able to support H.264.
… The good news for those looking for video quality improvements in BBC iPlayer is that, starting this week, we’re going to be encoding our content in H.264 format at 800Kbps. Additionally, our media player now supports hardware acceleration in full-screen mode, giving a greatly improved image at lower CPU usage than before.
So they’ve got the clientside runtime technology already installed (Adobe Flash Player), and the production workflow almost migrated (changing to MainConcept encoders), and their content distribution network is about ready to go H.264 too.
Final element? User experience. You can’t yank peoples’ habits, expectations out from under them. That’s why the release will be in stages. First stage is offering parallel VP6 and H264, with VP6 as default, and H264 available via a “Play high quality” button. Once this is realworld-tested, the next stage is to turn on automatic bitrate detection, meaning that H264 will become the default on good connections. The stage after that would be analyzing bandwidth changes and audience desire. They’re getting their feedback a little at a time, not asking the viewing audience to change to too much, too quickly, without recourse.
Also see Erik Huggers, who gives the larger picture about the move.
In comments at Anthony Rose’s technical discussion: “Is this new codec going to be compatable with the Nintendo Wii?” This is a tough question… but it’s a valid question. iPhone and PlayStation owners ask the same thing. Nokia Internet Tablet, iRiver, and many other devices achieve standard capability via Adobe Flash Player. But it did take awhile before office printers standardized on Adobe PostScript… there will always devices which don’t include standard capabilities, especially during the early days.
Innovative file-format types do tend to be commodified over time… bitmap formats work better across devices now, and text is easier than in the early years. Mozilla will be adding the On2 VP3 codec next year, as has Opera. But I imagine it would be expensive for realworld video production workflows to distribute an additional older format of compressed video for a minority audience… desirable, sure, but expensive. See how it goes.
You’ve got to get all four legs of the stool solid: the production workflow, the distribution process, the clientside capability, and then the user experience. The BBC is a good example of how a video production group actually goes about this testing. I’m glad the BBC is so open about how they’re bringing about this work.