EBU Policy Statement on UHDTV

[Ken Ross]

Originally Posted by Alister Chapman

Broadcast changes are happening now, it's not a future thing. Services such as Netflix, Hulu, Amazon etc have grown exponentially in the last couple of years. We just dropped our multi-room satellite TV add on in favour of NetFlix and may well drop the satellite movie channels too. We must also remember that unlike a traditional broadcaster with a limited footprint, these online services have global reach.

The problem with internet provided TV is the compression. Netflix and others simply don't look as good as either satellite provided content, most cable and certainly OTA. So for a videophile that demands the best picture quality, it's very hard pulling the plug on the conventional providers.

The internet providers don't look bad (well, sometimes they do), but compared to our more conventional source providers, they simply aren't 'as good'. Black levels suffer, overall contrast suffers and the picture just doesn't have the 'sheen' that satellite, cable or OTA has.

[Alister Chapman]

The BBC are using just 8Mbps for HD broadcasts in the UK other HD channels vary between 6Mbps and 10Mbps. There is nothing stopping an online provider from using similar bit rates, or much, much more.

Digital broadcasting is tied to largely fixed bit rates to fit "X" channels onto "X" space. An online service can provide variable bit rate streams depending on the end to end network bandwidth. If you have a good connection you can get a better picture. It's not tied to to the fixed bandwidths allocated to specific transmitters or transponders.

Netflix currently provide streams up to 6Mbps for HD if you have a dedicated streaming device such as an Apple TV, WD TV, Roku etc or a TV with a hardware decoder. If you have a 4K TV with HEVC then you get 15.6 Mbps 4K. Netflix looks just as good as most conventional HD broadcasters in my home. Arguably NetFlix etc have an advantage in that they can spend more time getting a really good encode of their content as the encoding does not have to be real time.

[Ken Ross]

I think it boils down to the fact that Internet content 'could' have higher bit rates, but doesn't. I've got huge up & down speeds, but my HD Netflix picture is not nearly as good as my Directv picture.

[David Heath]

Originally Posted by Dave Blackhurst

I've suspected that 4K may "catch fire" more rapidly than expected, and the CONTENT will be streamed over the internet rather than traditional "broadcast" channels?

That may or may not be true, but in the context of this thread internet or conventional broadcast is irrelevant - we're talking about standards that are common to both. (At least some of the standards. Other standards will be relevant to broadcast but not internet delivery, and vice versa.)

The danger is that if more than a critical mass of 4K TVs get sold, but which can not handle higher frame rates (only 25p, say - not 50p, let alone higher) or better bitdepth etc it will set a default lowest common denominator standard by default. Which "broadcaster" (either traditional or one such as Amazon, Netflix etc) will even think of 50p or 10 bit for their 4K offerings if many of the 4K TVs out there won't be handle it!?! They'll just shrug and say, "OK, 4K, 8 bit, 25 fps it is then". Their advertising people will still be able to say "IN 4K!!!", which I suspect is what really matters to them.

History gives that leaving matters to the market is rarely a good idea as far as technical standards are concerned. It's no secret that when colour was coming, in the UK the commercial broadcasters and manufacturers were in favour of keeping the existing 405 line network and simply adding NTSC standard colour to that. Advantage - it could have been done sooner, and they saw it as financially good in the short term. Disadvantages - the country would have been stuck with a far inferior service to what eventually came about, and compatibility problems with the rest of Europe, and (as happened in the US) not much viewing would have been done in colour anyway in the late 50's, early 60's - the cameras and receivers were just too big, expensive and unreliable to become mainstream.

[Alister Chapman]

But unfortunately we no longer live in an age where traditional broadcasters such as those that work to, or will wait for the EBU guidelines have total control.

People want things now, they will not wait, unless the thing they are waiting for is clearly defined and within easy reach. If the EBU mess around taking a couple of years to come up with their guidelines, let alone actually implement any of the changes, it may well be too late.

This happened with HD where the EBU finally, after many years of discussion and debate declared in 2009 that the optimum standard for HD broadcasting was 720p50 and recommended that HD broadcasting should be predominantly based on 720p50. However early adopter HD satellite services had been broadcasting1080i since 2006 (largely due to the amount of content produced using 1080i29.97 rather than 720p) and 1080i25 soon became the de-facto standard. The EBU was still trying to push for 720p50 in 2010, but it was way too late by then. The EBU is simply far too slow to react these days. Really they should be defining the standards for beyond 4K now as 4K is in effect already here.

It looks like we will see 60fps HDR 4K TV's from Samsung and Sony this year with Vizio and others to follow early next year. Without clearly defined standards from some governing body, the TV manufactures will just create their own standards and build their own content delivery networks, they will not wait for the EBU.

[David Heath]

I don't disagree with a word Alister has written above - the fact is it's the reality. But I do note the choice of the word "unfortunately", so I'm assuming you don't disagree with the principle of what I've said? I agree that the EBU are far from perfect, and act slowly - perhaps inevitable, given the numbers of people they represent - but they are at least trying to act in the medium/long term, not the short term of the commercial interests.

It's between the camera and display that standards have most importance, and whilst that may not mean too much to a one man operator, it's when you come to large live broadcasts (think Olympics and World Cup) that they have most significance. You have to take into account all the in between equipment - vision mixers, routers, graphics, links, slo-mo, servers etc. OB providers don't want to have to worry about interoperability between all the equipment - they would like a situation of "is it 4K? - yes? - fine!"

Alister is also correct about the situation with current HD. The EBU desire for 720p/50 was laudable initially, but largely based on a relatively smaller screen size in the home than is now the case. (I think they reckoned 37" was likely to be the norm, with 42" the exception.) Flat panels came along, average screen size sored, and their assumptions were out of date almost before the ink was dry. Arguably the most unfortunate thing was that 1080p/50 was not included as part of the current HD spec - so DVB receivers would need to be able to decode it. That would not mean that anyone would initially have to transmit such - the receivers would still decode lower systems - but would mean that as technology advanced, it would be relatively simple for a broadcaster to switch to 1080p/50. They would know that no existing receivers (and their viewers! ) would be left with a blank screen.

[Alister Chapman]

Yes David, I agree with what you said, but I think that the EBU may be too slow to respond so the standards will end up set by the manufactures rather than any governing body.

[Shaun Roemich]

Originally Posted by Alister Chapman

but I think that the EBU may be too slow to respond so the standards will end up set by the manufactures rather than any governing body.

Then they won't be STANDARDS by definition and we'll see the whole VHS/Beta or HD-DVD/BluRay debacles repeat themselves.

Manufacturers don't typically play well with each other, with each looking for competitive advantage, and the result will be a morass of proprietary stuff that doesn't work together. IMHO.

While Netflix is starting a foray into independent production, a lot of the stuff we know and love is still being purchased/commissioned by the broadcasters. Disrupting THAT model would be an interesting one... I see a lot of seriously substandard content coming out if that happens as the lowest price to stream model couldn't possibly finance the big budget prime time series we all love to watch, at least without sold commercials. Then we're back to the broadcast model, only over IP instead of cable of OTA.

[Jon Fairhurst]

Keep in mind that the EBU deals mainly in broadcast and works somewhat parallel to SMPTE (which includes both the cinema and broadcast sides.) There's still a lot of work to do before broadcasters will feel comfortable building out a UHDTV head end. For higher frame rates such as 100 and 120, we don't even have timecode standards yet.

For broadcast transmission, we have DVB for Europe etc, ATSC for the Americas and Korea, and ARIB in Japan. And then there is FOBTV which is where the three groups compare notes. Broadcasts will definitely be standards-based rather than proprietary. (Let's not get into the transition plan though. That's the real challenge.)

For receivers, HDMI 2.0 lagged a bit, resulting in UHD TVs that couldn't handle 50 and 60 Hz. HDMI 2.0 is becoming available, so those 25 and 30 Hz TVs will just have been a temporary blip.

And then there's MPEG, which is working on HDR and other advanced topics.

From the cinema perspective, 4K has been around for some time. You can shoot it, edit it, grade it and so on. Any one of us in a large city could go rent a 4K camera (or grab one from the equipment closet) and shoot a short 4K film in a day.

But consider broadcast. Where do you rent a 4K truck? What broadcast 4K cameras do you use? Need an extreme zoom for sports? Where do you get a 2/3" 4K camera or an S35 sports zoom? What switcher, router, and cables do you use? What real-time encoder? What transport stream? What modulation?

4K for cinema is easy. UHDTV for live production and broadcast still has a ways to go.

[Roger Keay]

The SMPTE.org website has a "Report of the UHDTV Ecosystem Study Group" available under the Standards tab, Committee reports. It appears to be available for download if you provide them some identifying information.

[Alister Chapman]

But 4K live is already happening. GloboSat have a 4K truck as do Telegenic. In additon Telegenic also have a 4K mobile production unit. These were using in Brazil for 4K coverage of several world cup games. There are many 4K capable switchers, often an HD switcher can be used for 4K by tying together multiple channels. There's always the Blackmagic ATEM 4K switcher line which is remarkably low cost. Sony's F55 has a full 4K live fiber option and there are optical adapters to use 2/3" lenses on the s35mm sensors. Lenses are probably the weakest link right now but there are options.

[David Heath]

Originally Posted by Jon Fairhurst

For receivers, HDMI 2.0 lagged a bit, resulting in UHD TVs that couldn't handle 50 and 60 Hz. HDMI 2.0 is becoming available, so those 25 and 30 Hz TVs will just have been a temporary blip.

But of all the 4K TVs on sale at the moment, how many are capable of 4K at 50/60p? Looking around, I suspect the answer is "not a lot". Sony's main offering doesn't seem to be (though it will handle 1080p/50), and other manufacturers don't even seem to give any max framerate spec.

And that's the problem. If too many get bought, with customers eager to watch true 4K, then it's storing up a can of worms. There is no interlace at 4K, and for sport especially 50/60p is needed. So as more and more sport may become available at 4K/50p, all the early adopters presumably won't be able to receive it. Expect a lot of unhappy people......

The situation is the same as the very early days of HD, and it needs an equivalent to the "HD ready" logo - which specified a certain minimum technical and connectivity specification. (I seem to remember that was largely an EBU initiative?)

But consider broadcast. Where do you rent a 4K truck? What broadcast 4K cameras do you use? Need an extreme zoom for sports? Where do you get a 2/3" 4K camera or an S35 sports zoom? What switcher, router, and cables do you use? What real-time encoder? What transport stream? What modulation?

4K for cinema is easy. UHDTV for live production and broadcast still has a ways to go.

4K OBs aren't common, but a lot of the problems have been got over, as least as far as cameras, interconnect cabling and mixing go.

Experiments were done with football last year, there was more 4K broadcast from Sochi at the winter Olympics, and there is more still coming from the Brazil football World Cup. I expect that by the time of the next Olympics, 4K origination will be relatively common. But it's a general transmission/distribution standard that isn't there - and since I believe the World Cup coverage is 4K/60p, a lack of monitors to display it on....?

The only camera I'm aware of being used for 4K broadcast is the Sony F55, and it seems very suitable for the purpose. They seem to be taking the compressed RAW it produces down a fibre to a base end, which gives a huge range of control in terms of truck processing. (It's like going back to the days of separate R,G,B feeds to CCU's!!)

4K 2/3" cameras seem quite unlikely due to diffraction issues - they're only likely to be operable over a very small range of iris between wide open and diffraction limiting. As Alister says, the lens issues of a sports zoom have been largely overcome by the use of adaptors to allow standard 2/3" zooms to be used on s35 cameras like the F55.

There's a half truth going around that you lose a lot of light via such a convertor. In practice, for the same lens settings, it increases the focal length by a factor of about 2-3x and reduces the f number by 2-3 stops. My first reaction was "what! 2-3 stops light loss!" but if you think about it, that gets largely nullified by the larger sensor having an inherent higher sensitivity - and the effects tend to cancel out. If you like, no light gets LOST in the convertor - it's just dimmer, but spread over a wider area. So no change in low light performance. And same for depth of field considerations - larger sensor, longer focal length, but smaller aperture - so back to square one.

(**CAVEAT** The above assumes all else equal - and practically the big difference is that 2/3" cameras are 3 chip, s35 are single. That difference - not sensor size - DOES mean about a stop drop in lowlight performance compared to a 2/3" 3-chipper. But it's not the near 3 stop difference that gets wrongly assumed.)

[Ken Ross]

Originally Posted by David Heath

But of all the 4K TVs on sale at the moment, how many are capable of 4K at 50/60p? Looking around, I suspect the answer is "not a lot". Sony's main offering doesn't seem to be (though it will handle 1080p/50), and other manufacturers don't even seem to give any max framerate spec.

This is not correct. Virtually all 2014 UHD TVs are 4K 60p capable. This includes Sonys, Samsungs, LGs and the upcoming Panasonics and Vizios. Additionally, many of the 2013 UHD TVs have been upgraded to bring them from 4K 30p to 4K 60p.

So this is simply not an issue any longer.

[Jon Fairhurst]

Originally Posted by David Heath

...The situation is the same as the very early days of HD, and it needs an equivalent to the "HD ready" logo - which specified a certain minimum technical and connectivity specification...

CEA just announced such a specification last month, including a 60 Hz minimum requirement.

CEA Updates Characteristics for Ultra High-Definition Displays - CEA

[David Heath]

Originally Posted by Ken Ross

This is not correct. Virtually all 2014 UHD TVs are 4K 60p capable. This includes Sonys, Samsungs, LGs and the upcoming Panasonics and Vizios. Additionally, many of the 2013 UHD TVs have been upgraded to bring them from 4K 30p to 4K 60p.

So this is simply not an issue any longer.

It may be a matter of where you live - I looked on Sony's US site, and what you say is certainly true there - they clearly specify 3840x2160 @60p and USB2.0 against the whole range, for example. Try to do the same thing on the .co.uk site and there is a glaring absence of the equivalent information. I bought a small TV for my son yesterday and took the opportunity to ask about framerate and 25/50p for the 4K sets - I might as well have asked the question in Russian. The best I got was that "this one has 1000Hz picture processing?" (Which may be true, if not very helpful.)

Originally Posted by Jon Fairhurst

CEA just announced such a specification last month, including a 60 Hz minimum requirement.

It's a step in the right direction, but really it's the bare minimum I'd expect. 50/60p is good - but there's a lot of talk that 4K really needs 100/120fps, and the CEA spec only requires 8 bit to qualify for the logo.