Is Ultra HD really 4K?
An interesting article taken from another site:
What's in a name?
OK, so that’s a fairly oblique question to kick off proceedings but it’s one we feel merits discussion. With the term 4K being bandied about left, right and centre as the de facto name for the next big thing in video – and we’re as guilty as the rest – it’s probably time to lay down a few facts. 4K, in its Digital Cinema guise, has a native resolution of 4,096 x 2160 pixels, whereas the Ultra HD TV standard carries a 3,840 x 2160 count. Clearly we can see one of those has justifiable claims on the 4K nomenclature and it’s not the latter so perhaps it’s time we towed the Consumer Electronics Association (CEA) line and began referring to the newly approved TV standard by its correct title? The content we’ll soon be able to receive through all those new TVs we saw at International CES 2013 is not 4K and never will be. Still, old habits die hard and we expect at least half the industry will still be calling it that until it’s replaced by the next TV resolution revolution, whereupon we’ll all be wrongly calling that 8K – it’s resolution is actually 7,680 x 4,320, precisely double that of Ultra High Definition which, in the context of this discussion, seems an unusually logical progression. So, can we make a pact that we all use Ultra HD from now on? We thought not.
So why does the TV standard not follow that of the 4K digital cinema projection standard? Simply because it’s going to be a damn sight easier to scale existing 1080p ‘Full’ HD TV content (can they keep calling it ‘full’?) in to the 3840 x 2160 resolution, which is also 16:9 in screen ratio, and precisely double both the horizontal and vertical resolution of the 1080p HDTV standard; giving four times the pixel count. The digital cinema 4K standard gives a screen ratio of approximately 1.89:1 (256:135 to be pedantic) but since there’s the same number of vertical lines of horizontal resolution (yes, we know), it shouldn’t prove too tricky to fit in. Confused? Don’t worry, all will soon become clear, especially as the 4K revolution has been picking up pace since CES.
So that you don’t have to worry about the intricacies of mastering Ultra HD TV content and all that mumbo-jumbo, Sony has stepped in to take care of business by preparing to launch an Ultra HD television post-production unit in California. It will become a division of Colorworks, a Sony Pictures Technologies’ post-production company. The facility will offer support to any programming that is shot in the format as well as 4K remastering for archived series that were shot on film. For any new programming, Sony intends to provide both an HD master for today’s distribution requirements and a 4K master that would be available for future use. So that’s the mastering being taken of.
Sony are also planning to announce details of their Ultra HD eco-system later in 2013, which will answer some questions on how it’s to be delivered. We’ve begun to wonder if this will coincide with the expected – and almost certainly imminent - reveal of the PlayStation 4. The PlayStation 2 helped launch DVD, the PS3 was a major driving force in Blu-ray adoption, so PS4K anyone? We certainly wouldn’t bet against it being at least part of Sony’s Ultra HD strategy. It looks like, initially at least, Sony’s plans are for a download/streaming service and such an idea will no doubt be greatly benefited by the recent adoption of the new ‘High Efficiency Video Coding’ (HEVC) standard by the members of the ITU (International Telecommunications Union). The ITU are a United Nations body and basicallyit when it comes to broadcast video standards.
HEVC should help to unleash a new phase of innovation in video production in Ultra-High Definition TV. The new standard is designed to take account of advancing screen resolutions and is expected to be phased in as high-end products and services outgrow the limits of current network and display technology. Companies including Broadcom, Ericsson, Mitsubishi and NHK have already showcased implementations of HEVC. The ITU/ISO/IEC Joint Collaborative Team will also continue work on a range of extensions to HEVC, including support for 12-bit video as well as 4:2:2 and 4:4:4 chroma formats. In layman's terms, that means an improvement on gradations of colour in video. As resolutions increase, it’s certainly going to be easier to see the limitations of 8-bit.
Although HEVC is certainly going to help get Ultra HD TV off the ground – it’s still going to require a lot of bandwidth for broadcast. Eutelsat, the World’s first satellite Ultra HD TV channel launched just before CES 2013 opened its doors and uses HEVC’s predecessor – H.264 - as its method of video encoding. Given that Eutelsat requires 40 Mbit/s, the more efficient new codec should be capable of halving that bandwidth but that’s still out of reach for significant numbers of the population. Not that it’s stopping some of the major players in the broadcast announcing their plans for Ultra HD, post CES.
Perhaps the most illuminating news came from the Daddy of broadcast U-HD, Japan’s giant, Government owned NHK Corporation. Before events unfolded in Las Vegas, NHK weren’t really bothering with 4K, their sights were firmly set on the higher Ultra HD standard - 8K (see, we’re already getting it wrong). To muddy the waters further, NHK like to call it Super-Hi Vision but it might as well be Super-Pi in the Sky vision for the time being as not only are the infrastructures nowhere even close to being able to carry it, as far as we know there’s hardly any camera’s in existence capable of capturing such a resolution. One that’s likely to need far higher frame rates than currently used to avoid it becoming a blur-fest in any case. More frames per second equals added bandwidth over and above the extra the added resolution will require. It will happen but it seems NHK has cottoned on to the fact they need time it well. There’s also the consideration that the Japanese Government may just want to lend a helping hand to the likes of Panasonic, Sony, Sharp and Toshiba, all of which are struggling badly in the display sector; each had 4K TVs at CES, of course. The upshot of NHK’s new found enthusiasm for the ‘lesser’ U-HD format is that they will be in Rio de Janeiro to commence broadcast of the World Cup in a 3840 x 2160 resolution. That’s two years ahead of the previous schedule they set to show the 2016 Olympics in U-HD from the same city. Reality check, back-scratching or sensible commercial decision? Probably a combination of all those factors.
NHK aren’t the only giant broadcasters making some Ultra HD moves since CES 2013 either. In the last week alone (at the time of writing), the BBC and CBS announced some plans of their own. The Beeb announced that it will be filming one of its next high profile wildlife series in ultra-high definition video. Director, Mike Gunton, is certainly very enthused about the benefits the higher resolution brings but noted post-production was slow, owing to the huge file sizes Ultra HD entails. They might be just one of the first in the queue at Sony’s new Colorworks facility. Out in the States, CBS, meanwhile, is to capture the 47th Super Bowl at Ultra-HD resolution for the first time. CBS are employing FT-ONE cameras that can capture 4K at up to 900 frames per second, which is a staggering 15x the current top frame rate. Admittedly, only 6 of the 70 cameras CBS will be using at Super Bowl XLVII are capable of the higher resolution but it’s another step in the right direction. With three major, global broadcasting corporations making announcements, within seven days of one another, surely it's a sign of things to come. We said during CES that it was going to be coming quicker than many thought and recent events haven’t changed our views on that one iota.
It’s believed that LG has so far shifted around 300 of its 84-inch Ultra HD LM960V TVs but despite the paucity of content, very high entry fee and nothing plausible, so far, by ways of a viable playback method, the NPD group predicts half a million U-HD TVs will be sold, globally, this year. That number is expected to rise to 7 million units in 2016. Interestingly, the NPD report predicts that China will be ahead of the USA in terms of sales and if the evidence of CES 2013 is anything to go by – and it should be – the Chinese will, by then, have plenty of their own home grown manufacturers to sate their thirst for the new format. They seem to have all the technology, they just need to acquire the marketing skills and secure more commercial relationships before really taking on the old guard.