Ultra HD HDR Interoperability and the World Cup

This year we experienced the first mass market UHD HDR event that was a truly World scale and it highlighted both the maturity and immaturity of UHD HDR. This was the 2018 World Cup in Russia. It exercised the state of art in HDR live production, contribution, distribution and consumption, all the way through to the TV. During the Ultra HD Forum Masterclass on “UHD Take-up in the Field: A year of Olympic and FIFA World Cup success”, I offered forth views and understanding of how the consumer experienced the World Cup and the challenges that were seen by them. During the conversation I offered only a small window on our understanding, which I expand on in this blog post.

A significant number of consumers across multiple countries (up to 10% according to Joerg Sander, CTO HBS) were able to receive and enjoy the HDR delivered content in either PQ (HDR10) or HLG. The days where consumers were concerned as to what HDR format was being used is definitely over, with post 2016 HDR displays supporting both formats with equal measure. However a number of interoperability ‘snagging’ issues were identified that we have been investigating and continue to investigate/resolve.

The Ultra HD Forum took an active role in reviewing the experience that consumers had across the world (this was done by reviewing and monitoring multiple online video forums, where active consumers shared their experiences), combined with our interoperability experience of the last three years and specific work undertaken during a Big Interop event that was run in London in parallel with the DTG/DTVP 8th UHD Plugfest. It was focused on multiple interop angles of broadcast and streaming delivery of UHD HDR, alongside work on HFR, and also allowed the viewing of the World Cup from multiple providers in the same location (via SDR and HDR).

Some of the ‘snagging’ issues that were seen from all these sources were:

Operational/Production Issues

  • Specifically in the first game of the World Cup, there were issues with configuration which resulted in less than optimum experience of HDR by consumers. This issue was quickly fixed for further broadcasts
  • Differences in the HDR reproduction as transmitted generated by platform/broadcaster distribution differences – most of which were not apparent unless you were able to compare services side by side from different operators
  • Downstream distribution issues with items such as audio sync occured, issues which were resolved/adjusted
  • Differences in configurations between different stadiums
  • Stadium scene issues where sunlight or lack of sunlight impacted the overall presentation

General HDR TV Display issues

  • Some consumers reported that the HDR image was darker than they expected, particularly when compared to SDR (aspects of this are expected due to consumers getting accustomed to overly bright SDR reproduction at 2 or 3 times the correct luminance, and then having it adjusted back for correct HDR reproduction)
  • The HDR wow factor was not seen except in certain circumstances such as sunlit pitches/crowds
  • Support for HLG and HDR10 (PQ10) is pretty universal on post 2016 TV displays however some displays required post manufacture update to be able to support HLG which had not been completed, resulting in a less than optimal experience either as SDR or as buggy HDR support
  • Poor reproduction of HDR including incorrect color reproduction and sometimes garishness
  • The majority of TV displays with HDR capability provided a good/great experience, but there was also a number of low end displays that had poor colour reproduction, poor tone mapping handling, and buggy HDR/SDR signalling support
  • Colour reproduction was not always as the consumer expected, with comparison of colours between the SDR HD and HDR UHD services and the consumer sometimes having a preference for the SDR HD colour version ( affectionally known as the ‘green grass’ issue where SDR grass is greener/brighter than the more natural HDR reproduction )

Grass.jpg

STB oriented Platforms

  • Operators with HDR supporting STBs and clear communication about updating TV displays, had a good HDR experience (many of whom are Ultra HD Forum members)
  • Operators that had not confirmed HDR support on their STBs had a number of issues, from a best case of SDR only to a much worse ‘buggy’ incorrect colour experience because the HDR support was not deployed on STBs in a working state. Several of these operators took the hard decision to switch back to SDR to ensure a good experience for their consumers
  • Some operators did not communicate that their STB platforms supported HDR HLG and so consumers were surprised to find that they could access the experience, and enjoyed an excellent HDR experience

Over the Air / Free to Air

  • Not having an STB to manage the display support meant that OTA oriented countries had a varied experience.
  • Some consumers with non-conformant TV displays, particularly old firmware 2016 displays and pre-2016 4K SDR displays, had incorrect colour reproduction from just trying to display a channel for which they did not have capability to display. Some operators with this issue also took the hard decision to switch back to SDR delivery

Streaming

  • Streaming over the top was undertaken live in the UK and on demand in the US. Streaming was influenced by the network performance as would be expected, particularly with high bit rate requirements but generally this was managed well, something that the BBC have communicated extremely clearly on for example.
  • Some UHD HDR capable STB devices did not have access to UHD HLG HDR streaming due to lack of HLG support, but had a full SDR UHD experience, with some annoyance being shown by consumers owning these STB devices
  • Some otherwise UHD HLG HDR capable TV displays and devices did not have access to UHD HLG HDR streaming due to issues surrounding non-HDR related hardware/software support, which again there was annoyance shown by consumers owning these displays/devices
  • Some consumers used HDR capable devices combined with devices to manipulate the HDR signalling to access streams in “HDR HLG” but these applied the incorrect transfer curves to the content so it was a colour distorted – consumer Frankenstein setups that gave a poor experience which would be fine but for the fact that these persons then complained about this experience online, adding to the noise of people having issues

Next Steps

Since the end of the World Cup, I have been involved in analysis of the causes of the issues that were seen. This is something that is ongoing in the Ultra HD Forum and is feeding into future Interop work which the Forum will report on in due course.

As we reiterated in the panel, although it may seem that we are bringing up a number of issues that affected the experience by consumers, the vast majority of consumers of the UHD HDR delivery had a good/great experience of the World Cup and did not see the issues we describe in this post which is a record of the perfectionism that we as an industry have for what we do. The World Cup experience was an excellent outcome for UHD HDR and will surely drive more services and events taking place in HDR.

Ian Nock is the Founder of Fairmile West, which is a Consulting company focused on working in the Consumer Device and Video arena. We work with clients on technology strategy and product delivery through key practices in Consumer Devices and Video Services. If you are interested in learning more about what we do, please do get in touch via our website – Contact us. You can also keep track with what interests us in the industry by following our Link blog at TV Tech News, and you can specifically follow news on Ultra HD via the following link – Ultra HD News.