VVC – MPEG’s new codec

VVC has now been released, MPEG’s successor to HEVC, named Versatile Video Codec, it aims to do more than ‘just’ provide 50% bitrate savings over H.265. This article will look at the details.

VVC joins us in an increasingly complicated codec landscape. Many industries have benefitted from the AVC (A.K.A. H.264) standard being so widespread. 20 years old now, it’s made its way into pretty much every product that does video; If you want to give someone a video, encode it as MPEG 4. We can’t use AVC forever because better workflows, better viewer experiences, new businesses and lower costs all round would be possible with codecs which performed better.

The contenders have been lining up over the years, HEVC had a go and whilst there certainly has been adoption, that’s hardly had any impact on AVC. It’s widely seen as a technological success but commercial failure as many companies have refused to deploy it for fear of being struck with unexpected licensing fees for patented technologies contained with. VP9 has arrived and seen some success. Having been developed by Google, all Android phones are capable of decoding it so YouTube has seen success using it, as explained by Matt Frost from Google Chrome Media in this video. AV1, too, is in use having been developed by the Alliance for Open Media whose founding members include Netflix, Apple, Amazon, Google and Microsoft. Again AV1 is in use on YouTube and also Netflix and Facebook. AV1 adoption outside of the giants, however, is not yet apparent.

There have been a number of talks on VVC over the last year which help give a good overview. This talk from Bitmovin, VVC, EVC, LCEVC, WTF? – An update on the next hot codecs from MPEG, is a great start to understand not only VVC but the two other codecs coming from MPEG. To understand why it’s called the Versatile Video Codec, it’s best to look a little deeper at the new tools which have been brought in. These details are examined in a talk from Mile High Video by Benjamin Bross and this one from Microsoft’s Gary Sullivan. Both look at the different types of video, such as screen content which can now be handled better. Computer graphics tend to have sharp edges and, whilst the art and science are continually advancing, don’t look natural both in cut-scenes but also in the in-game play. This is to be expected of course, as to have controls and information on-screen is important and games like Magic: The Gathering are not intended to look ‘real’ per se. As such, if the codec has techniques that treat the video differently to natural images like sunsets and faces, screen content will look better at a lower bitrate. This is one example of what VVC brings in as default.

There are open questions for VVC – will there be hardware support? At CES 2020 there were a number of announcements of AV1 support in smart TVs driven by its adoption by Netflix among others and the need for a codec which performs sensibly at 8K. Whilst AV1 isn’t immune to patent challenges, the chances are that the ‘royalty free’ promise of AoM will pay off, so where will the impetus to also support VVC – which definitely will have royalty payments – come from?