WHATWG drops <video> and <audio> codec requirements from HTML5 specification

Ian Hickson, the author and maintainer of HTML5 specification, announced that the open source codec Ogg Theora is no longer a requirement for <video> and <audio> in HTML5. Ogg Theora was dropped from specification because not all vendors are willing to implement and ship the open source codec. The matter is left as undefined, as is the case for <img>, <embed>, and Web fonts. Each browser will support the video and audio codecs they prefer.

The current situation regarding the <video> codecs support in browsers is the following:

  • Safari browser will not support Ogg Theora by default because Apple refuses to implement the codec in Quicktime due to lack of hardware support and an uncertain patent landscape. Apple claims there may be some patents covering Ogg Theora that are unknown at the present time. Apple wishes someone to prove there are no patents covering Ogg Theora before dropping this claim, while they do not research the patents themselves. Apple is one of the licensors of the H.264 codec, a proprietary codec patented by MPEG LA, a direct competitor of Ogg Theora.
  • Chrome browser supports the H.264 and Ogg Theora codecs, but Google cannot provide the H.264 codec license to third-party distributors of Chromium. Google also believes that Ogg Theora's quality-per-bit is not yet suitable for the volume handled by YouTube, although Ogg Theora is less computational heavy than H.264 when encoding or decoding video.
  • Opera does not support the H.264 codec due to the obscene cost of the patent licenses.
  • Mozilla browsers does not support the H.264 codec because they can not obtain a license that covers their downstream distributors.
  • Internet Explorer browser does not support <video> at all, and Microsoft is not interested in commenting about this.

Ian Hickson mentions that for video codecs to be included as requirement in HTML5 specification, the following needs to happen:

  • Ogg Theora improves the quality-per-bit and video quality for HD, vendors will make Ogg Theora decoder chips available to the public, and major browsers will include Ogg Theora without getting sued.
  • H.264 patents expire, which will no longer require license fees for H.264 support.

A few years need to pass in order for those things to happen, and similar conditions apply to <audio>.

The current legal situation for using video codecs:

  • Encoding a video using the the H.264 codec requires paying license fees to MPEG LA. These fees change every few years.
  • Ogg Theora is open source, but lawyers can not determine if it's really free or not to use due to unknown patents that may apply to the codec. Using Ogg Theora to encode a video is free, with the risk of the possibility of getting sued in the future by someone claiming patent violations on pre-existing code.

Comparisons between Theora and H.264 codecs indicate that for normal video, Theora's quality is similar to H.264. For HD, H.264 gives better results. Theora's quality-per-bit is somewhat lower than H.264, but improvements in the codec will result in better numbers. Theora is less computational intensive than H.264 when it comes to decoding and encoding video.

The final HTML5 standard will come from W3C. In theory, there is still a chance for Ogg Theora to make its way back into HTML5 specs if W3C does an extensive patent research and finds that no patents apply to Ogg Theora. If this is the case, then chip manufacturers will have a better incentive to include Ogg Theora decoders.


Theora is an open and royalty-free lossy video compression technology being developed by the Xiph.org Foundation as part of their Ogg project.

H.264/MPEG-4 AVC is a standard for video compression.

MPEG LA, LLC, is a firm which licenses patent pools covering essential patents required for use of the MPEG-2, MPEG-4 Visual (Part 2), IEEE 1394, VC-1, ATSC and AVC/H.264 standards.

The Web Hypertext Application Technology Working Group (WHATWG) is a coalition of companies working to develop HTML 5.

Ian Hickson is a Google employee, the author and maintainer of the Acid2 and Acid3 tests, the Web Applications 1.0/HTML5 specification, and a co-editor of the CSS 2.1 specification.

The World Wide Web Consortium (W3C) is the main international standards organization for the World Wide Web.