There was a hint of backlash against 8K at the recent NAB 2019 Show in Las Vegas and TV makers have only themselves to blame. It was at the previous big US show, CES 2019 in January, that a group of CE makers launched the 8K Association with a remit to “educate the market” about the technology’s potential value for service providers as well as content creators. Founding members included panel maker AU Optronics, but more significantly Hisense, Panasonic, Samsung and TCL. Yet it was names not on the list which raised eyebrows and set the more subdued tone for 8K at NAB, with Sony and LG the most prominent omissions.
The criticism is that CE makers are merely reacting to their failure to establish decent profit margins for 4K TV sets in their bid to carve out market share there and are looking to 8K as a quick route to higher top end returns among early adopters to compensate. TV makers have traditionally been guilty of promoting technologies prematurely – or as in the case of 3D six years completely erroneously – in order to generate as much profit as possible from pushing models that give consumers few if any real benefits at the time.
8K is not another 3D and will over time deliver a variety of benefits, beginning in the relatively near time on the production side. But at a time when 4K is only emerging, widespread 8K distribution is at least a decade away and it is absurd for the 8K Association to list as one of its immediate objectives “encouraging service providers (especially OTT) to develop 8K offerings”.
The absence of Sony and LG from the 8K Association underlines why talk of commercial 8K services, at least outside Japan, is premature. Japan’s NHK has been a cheerleader for 8K for almost a decade now and already offers a commercial service, which for the rest of the world this will serve as a laboratory rather than example for them to follow in the near term when they are struggling to develop the capacity and infrastructure for 4K at just one quarter the areal resolution.
One of the problems is that there are no standards yet for 8K beyond headline resolution and each manufacturer is ploughing its own furrow in an attempt to tilt the early market in its favor and gain the most traction. That is largely why Sony and LG have declined to join the 8K Association at this stage, believing it would distract them from their efforts to catch up with their rivals as late entrants to the scene. It does not reflect lack of interest in 8K but perhaps a late awakening to the perception they must get a stake in the ground. Sony recently revealed plans to develop super-large TVs with its Z9G 98-inch and 85-inch displays, while LG is persisting with its OLED (Organic Light Emitting Diode) technology with its 88-inch OLED display.
All these TV sets represent great technological achievements, but the fact all are larger than 85 inches highlights their irrelevance for nearly all consumers at this stage. It is only possible to distinguish between content shot and distributed in 4K and 8K on screens of this size and even then, only when close up. In practice people would view such large screens from slightly further away to have a reasonable aspect ratio and then would not be able to distinguish between 4K and 8K. Indeed, focus groups have consistently shown that standard full HD at 1080p combined with HDR yields a better viewing experience than 4K without HDR.
Where the high resolutions can score is in zooming in on areas of the picture and that is a use case sometimes cited for 8K as well as 4K. When one small area is blown up to the full screen then the experience can be greatly improved by having more pixels available. Suppose for example a viewer wanted to zoom in on an area just 5% of the total picture, say a portion of a football crowd where a fight had broken out. At 8K resolution, pixel density is 16 times as great as at full 1080p HD. Therefore at 8K, 5% of the screen area would generate about 80% (16×5) the pixels of a normal full HD display and so would still be reasonably sharp. Otherwise it would start to look grainy.
That, however, is a long way off and in the shorter-term use cases for 8K are confined to the production side, as came out at NAB. Harmonic was foremost in demonstrating 8K production alongside 4K production and comparing the two. The interesting point highlighted by Thierry Fautier, VP of strategy at Harmonic as well as President & Chair of the Ultra HD Forum, was that 8K production yields a better 4K experience. In other words, content produced with 8K cameras and equipment looks better on 4K displays and for that matter on full HD displays. This was set out in a position paper on 8K published by the UHD Forum at NAB, setting the stage for more detailed demonstrations at IBC 2019 in September, according to Fautier.
This process of capturing in 8K even when all the content will be consumed at lower resolutions is known as oversampling, because more pixels are generated than can ever be displayed. The advantage is that there is more information for generating the pictures at lower resolutions and so better decisions can be made about color and luminance of individual pixels after down-conversion, improving the overall picture quality. AI and machine learning techniques can help with this processing much more than in the past.
There is also potential for use of AI in the opposite process of up-conversion, taking footage shot at 4K most likely and extrapolating to generate 8K pictures. In this case decisions need to be made over color and luminance of additional pixels by considering the smaller number already captured and here again there is evidence that the experience can be improved for those consumers with 8K sets. So, there may be some benefits owning 8K sets after all, although again with the caveat that HDR makes a bigger difference to the experience.