What WebM means for web video

Today Google launched WebM (project page), a royalty-free video format consisting of the WebM container (a “subset of the Matroska multimedia container format”), the VP8 video codec (acquired by Google when it purchased On2 Technologies), and Xiph.Org Foundation‘s Vorbis audio codec. Thanks to Google’s many WebM-related partnerships with hardware and software companies, we may finally have a codec that breaks through the codec logjam. Here’s why:

Ubiquity in web browsers

The most critical factor for a video format’s success is how many people can view it. Within a year, over 90% of web users will have a WebM-compatible player in their web browser. This is primarily because Adobe is adding VP8 support to Flash. As most users of Adobe Flash Player update regularly and about 93% of web users have Flash, Adobe’s VP8 support alone should push WebM usage share close to 90%. Once one factors in all the WebM-capable browsers: Firefox, Opera, and Chromium, that figure will easily pass 90%.

Perhaps most importantly, the ubiquity of WebM decoders in web browsers will allow web developers to deliver their content using a single, royalty-free codec, which has previously been quite complicated. With Flash support for WebM, a developer can simply place a <video> tag around a Flash embed, ensuring that both WebM-supporting browsers and browsers without intrinsic WebM support (such as Internet Explorer and Safari) but with Flash will be able to view the video. By using a single royalty-free codec, web developers can avoid the hassle of encoding their videos in both H.264 and Theora (as is currently required for complete coverage) while at the same time freeing themselves of the legal shackles imposed by H.264.

While not all software players have official timelines for WebM support, it seems very likely that within a year, all of the software I mentioned will support WebM. Relatedly, I hope that Adobe will clarify their stance on WebM support as their public record endorses VP8, but not the Vorbis audio codec, which is required to fully support the WebM format, a combination of the two. Assuming Adobe Flash Player gets full WebM support, Adobe will have finally implemented the solution I proposed to fragmented codec support, for which I applaud them. This would give Flash a second royalty-free audio codec, Vorbis, in addition to the Speex codec it already supports.

Implementations for mobile devices

One of the big reasons Theora hasn’t become more widely-adopted is its relative lack of support among mobile devices. No cell phone I’m aware of ships with a Theora decoder by default. Firefox for the N900 renders Theora, but its implementation is not optimized for the hardware, making even 320×240 video difficult to decode in real-time.

WebM is launching with a long list of mobile hardware manufacturers that will support the effort, including ARM, Broadcom, MIPS, Nvidia, Qualcomm, and Texas Instruments. Broadcom plans to launch WebM support in its VideoCore chips in Q3 2010 while Android will support WebM in Q4 2010. This will give WebM a major foothold in the mobile markets, something which no royalty-free video format has had before.

Hurdles

Neither Microsoft nor Apple has indicated they will ship WebM support in their operating systems or mobile phones. On the desktop side, this won’t be an issue since Flash’s WebM support will make up for Windows’ and Mac OS’ WebM deficiency. However, on the mobile side, the iPhone’s 15% market share could pose a problem if Apple refuses to support WebM. Note that Apple and Microsoft will support WebM for browser video playback (just as they currently support Theora), but only if the appropriate codecs are installed, which is often too much hassle for the average user.

WebM does not appear to specify profiles currently, as H.264 does, which could limit its usefulness in the mobile space where guarantees on decoding complexity are important for rendering smooth video consistently. It seems that WebM is still under development so this situation may be remedied in the future.

Learning from Theora

Theora will remain an important codec for the foreseeable future, as web sites and browsers transition to WebM. While the quality of Theora videos is demonstrably on par with H.264, many leaders of the web choose to believe otherwise, instead claiming Theora takes up too much bandwidth and H.264 is “a vast improvement in quality-per-bit over Theora”. With attitudes like these and with no help from Microsoft, Apple, Adobe, or hardware manufacturers, Theora was unable to gain the momentum needed to become a dominant player in web video. Thanks to a large corporate backer that can afford to pay for the necessary hardware and software implementations, a new brand with no bad press or preconceived notions of inferiority, and its royalty-free nature (allowing it to be used in Firefox and Opera), WebM will over time replace H.264 as the new de facto standard for web video.