The Search for a Royalty-Free Video Codec
By Arianne Hinds, Lead Architect, Standards Strategy, Office of CTO, CableLabs –
Recently, there have been some discussions in the news about the quest for a royalty-free video codec in key standards organizations. How did this quest get started and what exactly is a royalty-free video codec anyway?
For starters, a codec is short for “coder-decoder” that is capable of compressing and decompressing large media files containing music or video. Codecs make it possible to deliver music or video over cable networks, or the Internet for that matter, so that these media files do not consume enormous amounts of bandwidth while being transmitted.
A royalty-free video codec is one that is licensed or otherwise available free of charge for use in some or all applications, i.e., through some form of agreement by the owners of the underlying intellectual property rights that the technology can be licensed without a fee. As cable set-top boxes collectively represent a large application and use of codecs, a royalty-free codec could be an attractive option versus a royalty-bearing codec.
A royalty-bearing licensing model has sufficed for traditional pay TV service providers because a simple one-time license fee is generally built into the cost of the set-top box. However, in web- or cloud-based markets there is no singular device owned by the video provider to attach a license fee. Rather, the video service is typically provided via web browsers that are generally deployed for free. So, the hunt is on for a royalty-free codec that may be better suited in the Internet driven marketplace for video distribution.
Two key standards bodies, the IETF and the W3C, which are responsible for developing the specifications for the Internet and the World Wide Web, have been collaborating on the development of a new real-time communication standard called WebRTC. More specifically, the W3C has requested that the IETF recommend a video codec that will be mandatory to implement for this new standard and their preference is that it would be a royalty-free codec. Why? Because most standards that are developed for the World Wide Web are indeed royalty-free standards.
In response to this request from the W3C, the IETF has launched a project to identify a royalty-free codec.
It is worth noting that for the last decade, MPEG has been exploring the feasibility of a so-called “Type 1” standard for video coding. What is a Type 1 standard and how is it different from a royalty-free codec? A “Type 1” standard is a formal standard published by a standards organization for which patent holders are prepared to grant licenses free of charge whereas a royalty-free codec is not necessarily a formal standard; for example, an open source project. This move by MPEG was seen by some as especially compelling because MPEG traditionally develops high-performance standards that are typically royalty-bearing. More recently MPEG has actually launched a project to develop a Type 1 video coding standard, intended for Internet applications.
These separate but related efforts have sparked an intense competition as to what will be the preferred royalty-free video codec. Interestingly, amongst the codecs being considered in both MPEG and the IETF, the two candidates that appear most likely to succeed are the same two video codecs: VP8 and AVC!
Power in your Corner – Who’s backing which Codec?
VP8 is owned by Google, which has worked with MPEG LA to arrive at an agreement with most of the owners of essential patents so that Google can absorb licensing fees for these patents to help make VP8 royalty-free. VP8 is available from the WebM open-source project managed by Google.
The MPEG Type 1 AVC codec being considered differs from the current AVC codec that is widely deployed in set top boxes, which is not royalty-free. How are these AVC codecs different? It turns out that years ago, when AVC was first being developed, MPEG created the Constrained Baseline profile, which was expected to become a limited and royalty-free version of AVC. The result was not widely adopted for multiple reasons, including reasons related to the licensing issues for the underlying patents. The more widely deployed AVC codec is the High Profile for AVC (again, not royalty-free).
One of the major proponents of the royalty free Constrained Baseline AVC codec is Cisco. How far is it willing to go to win this race?
Last year, Cisco boldly announced that it would open source its AVC binary executable and that it would absorb the associated MPEG LA licensing fees so that AVC can be made available for use in the web for free. That was pretty exciting news, and clearly an indication of lengths Cisco is willing to go to help sway the outcome of this race in favor of AVC. More recently however, MPEG closely evaluated the visual quality produced by both the Constrained Baseline version of AVC and VP8. Based on the test results reported at the January 2014 MPEG meeting, MPEG has initiated the steps to formalize VP8 as a new addition to the MPEG-4 suite of standards. This action by MPEG is a credit to MPEG’s recognition that while it develops world-class standards from the ground-up, some technologies that are developed for specific applications could also be formalized as standards.
Ultimately, a final selection and corresponding announcement one way or the other by MPEG could carry leverage into the codec competition underway in the IETF. In the meantime, the quest for a royalty-free codec awaits a final outcome.
Dr. Arianne Hinds joined CableLabs in 2012 and is currently responsible for orchestrating the participation of CableLabs in industry consortia and standards developing organizations. She is an active participant in MPEG, and currently chairs the INCITS L3 Technical Committee, the parent committee overseeing the participation of the United States in both MPEG and JPEG.