I'm afraid you're wrong. With AVC, encoding 1080p/50 (50 frames per second) takes barely any more bandwidth than 1080i/25 (25 frames per second/50 fields per second)
"Takes barely any more"? The question is this: at a given bitrate (especially one that's likely to be broadcast), can you deliver appreciably better quality using 1080p50 than 1080i50 to a modern TV using a decent H.264 encoder?
If not, then talk of 1080p50 is pointless.
In practice, the results are content, bitrate and encoder dependent, giving the answer: sometimes yes, sometimes no.
, because interlacing is inherently inefficient in the digital world.
It help MPEG-2 to deliver better quality at a lower bitrate. That is the opposite of inefficient. Last time I checked, MPEG-2 was digital
FWIW it also helped raw uncompressed digital video maintain better quality at a given bitrate for over 20 years. In this realm (where broadcasters work) dumping interlacing means doubling the bitrate for far less than a doubling in quality. It you want to jump from interlaced to progressive without doubling the bitrate during production, you have to jump from 1080i to 720p. The drop in static resolution is easily visible if you do.
A quick look on Wikipedia provides 3 references for this alone:
The results of such tests are dependent on bitrate, encoder capabilities, content, and the display used.
It is true that interlacing can make no sense at all as a pre-process to an optimal video codec feeding a progressive display. However, video codecs are not optimal, and while some of the test results and demos appear conclusive, with real-world encoders and usage the situation is not nearly so clear cut.
(There have been demos where the protagonists have used an encoder that doesn't handle interlaced content properly to prove how much better progressive is, and demos where people have showed that 1280x720p is better (or at least never worse) than 1920x1080i on displays that only had 1366x768 pixels!)
1080i > 1080p is nowhere near enough of a night-and-day difference to justify upgrading the entire chain in one go. You can get so close with half-decent bitrates, decent encoders, and decent deinterlacers.
Beware that some of those who promote progressive encoding need it to crank the bitrate down (which is easier with progressive H.264). You can imagine where this path leads.
"Takes barely any more"? The question is this: at a given bitrate (especially one that's likely to be broadcast), can you deliver appreciably better quality using 1080p50 than 1080i50 to a modern TV using a decent H.264 encoder?
In practice, the results are content, bitrate and encoder dependent, giving the answer: sometimes yes, sometimes no.
Right. Depends on the source material I guess. For fast action shots or any scene where interlacing artefacts can appear then yes. For near-stationary scenes, 1080i is essentially 1080p anyway. But then when less things are changing on-screen, less bits are required anyway (assuming VBR). The major benefits will come during scenes where high bandwidth is needed, and that's where 1080p wins.
It help MPEG-2 to deliver better quality at a lower bitrate. That is the opposite of inefficient. Last time I checked, MPEG-2 was digital
I don't know much about MPEG2 so I'm happy to concede that MPEG2 wasn't that affected by prediction being harder when interlaced material is encoded. It is presumably more difficult for the advanced prediction techniques of AVC to work with interlaced material, so some of the benefit is lost. Interlacing works great in the analogue world but it doesn't work very well with modern digital compression. That won't change either, with HEVC being designed for progressive sources only.
FWIW it also helped raw uncompressed digital video maintain better quality at a given bitrate for over 20 years. In this realm (where broadcasters work) dumping interlacing means doubling the bitrate for far less than a doubling in quality. It you want to jump from interlaced to progressive without doubling the bitrate during production, you have to jump from 1080i to 720p. The drop in static resolution is easily visible if you do.
For uncompressed video, sure. It's only digital compression that doesn't cope that well with interlaced material.
It is true that interlacing can make no sense at all as a pre-process to an optimal video codec feeding a progressive display. However, video codecs are not optimal, and while some of the test results and demos appear conclusive, with real-world encoders and usage the situation is not nearly so clear cut.
Perhaps. I would love to see some actual 1080p/50 broadcasts that can be compared with 1080i/25 broadcasts, especially when using the same statistical muxing.
1080i > 1080p is nowhere near enough of a night-and-day difference to justify upgrading the entire chain in one go. You can get so close with half-decent bitrates, decent encoders, and decent deinterlacers.
Oh I know no-one's going to pay to upgrade entire chains. This is more about what should've been done in the first place but never mind - it seems that 4K or whatever it'll be called will be entirely progressive.
Also, it's hard to say that anyway. Where is the 1080p/50 material we can use to compare at home?
Beware that some of those who promote progressive encoding need it to crank the bitrate down (which is easier with progressive H.264). You can imagine where this path leads.
A lot of, ahem, "scene" releases encode 1080i/25 to 720p/25 to save on file size. iPlayer does the same. I am totally against this. I would much rather a 720p/50 file be a bit bigger, or, even better, just keep the original 1080i/25 file. That's what I do with my recordings.
Good job that didn't happen. 60Hz field rate, 50Hz mains supplies, crappy old sets with poor smoothing, the 10Hz flicker would have turned the viewers insane.
I did some research and found that the proposal by Cossor (who were Britain's leading pre-war set maker) was for 525-lines/50Hz.
I had a feeling that might be the case but didn't want to claim it as fact until I read it somewhere else.
Television line systems were all over the place between 1945 and 1950 and so not to be confused with the later CCIR and NTSC standards.
SuperHi is hardly likely to be a mass-market standard, and it is possible that the same could be said for 4K (with massive screen sizes that few homes could accommodate or afford).
Those are likely to be niche formats for large venues and those who have dedicated home cinema rooms with large screens/projectors.
I would disagree.
Many reports say 4K tv is set to be the next big thing as 3D hasn't sold as many new sets as manufacturers anticipated so it looks very much as though all new tv's will become 4K as standard just as all new tv's became HD.
4K is currently very expensive but was so was HD when it 1st came out. I remember 42" sets being £8,000. Now you can get one for a couple of hundred.
Also many PC games are going 4K with 4K monitors set to introduce 4K to the masses when prices fall.
As for delivery of TV restricted to DSat, fine if you have a dish or are able to fit one, fine if you are not disadvantaged by terrain or obstacles.
There are ways around that for black spots eg to have a local relay where the signal is received by dish and then converted to DTT and re-transmitted via an ordinary aerial mounted on a pole.
This already happens with DTT now eg this is a DTT relay transmitter, little more than a pole and cluster of aerials.
As for buildings that are subject to Listings etc, its usually possibly to have a hidden dish in the garden. That's what many listed buildings have currently.
PS don't visit this part of the forum very often so apologies if someone has already covered this - couldn't read 5+pages of replies!
Many reports say 4K tv is set to be the next big thing as 3D hasn't sold as many new sets as manufacturers anticipated so it looks very much as though all new tv's will become 4K as standard just as all new tv's became HD.
4K is currently very expensive but was so was HD when it 1st came out. I remember 42" sets being £8,000. Now you can get one for a couple of hundred.
Also many PC games are going 4K with 4K monitors set to introduce 4K to the masses when prices fall.
The trouble is, with an industry-led approach, consumers are unlikely to pay the initial high costs without the content to match. And unless that content becomes widely available, AND enthuses the consumers (i.e. it has to be demonstrably better than broadcast HD or blu-ray within the confines of a domestic viewing environment) then it is always likely to remain a niche (and premium) product. And even with strong high-street sales of 4K sets (driven by manufacturers flooding the market at the expense of existing sets, aka "manufacturer-led demand") it still needs that killer app (again demonstrably better than current broadcast HD or blu-ray) consumers will simply be buying them because there is little choice.
There are ways around that for black spots eg to have a local relay where the signal is received by dish and then converted to DTT and re-transmitted via an ordinary aerial mounted on a pole.
This already happens with DTT now eg this is a DTT relay transmitter, little more than a pole and cluster of aerials.
So it still delivers the signal via a terrestrial transmitter network!
As for buildings that are subject to Listings etc, its usually possibly to have a hidden dish in the garden. That's what many listed buildings have currently.
The trouble is, with an industry-led approach, consumers are unlikely to pay the initial high costs without the content to match.
I suspect most people with 4K sets will watch material upscaled from lower definition the same way "HDTV ready" owners do now.
Assuming it isn't the red herring that 3D turned out to be then Sky will be the main beneficiary as it will always be able to offer a far wider choice of 4K programming than terrestrial TV.
...with HEVC being designed for progressive sources only.
Sorry to be a pedant, but HEVC was designed for and handles interlace just fine (as you've mentioned in a previous post); 4K/8K UHD standards don't support it however, but you can guarantee a 4K TV will still handle interlace anyway...
The thing that I'm having the biggest issue with in terms of interlace vs progressive is that surely all of the cameras used to record HD footage are now progressive, so why convert it to a legacy format and lose 50% of the vertical resolution? In order to encode it the interlaced content will invariably be reconstructed into a full frame for reference! I'd prefer a more detailed frame and let my telly do some interpolation - it does a pretty good job of "24p" BDs.
As for those 720p "releases" you mentioned, they're fine for a phone/small tablet...
Sorry to be a pedant, but HEVC was designed for and handles interlace just fine (as you've mentioned in a previous post); 4K/8K UHD standards don't support it however, but you can guarantee a 4K TV will still handle interlace anyway...
There's a big difference between being "designed for x" and being able to "handle x fine".
Many reports say 4K tv is set to be the next big thing as 3D hasn't sold as many new sets as manufacturers anticipated so it looks very much as though all new tv's will become 4K as standard just as all new tv's became HD.
4K is currently very expensive but was so was HD when it 1st came out. I remember 42" sets being £8,000. Now you can get one for a couple of hundred.
8K will probably be the next big thing. 4K is something the manufacturers would like to sell to everyone in the meantime to keep a steady flow of income from early adopters.
Not through the transmitter network, through self-help relays funded and operated by the local community.
That's true, however my original ppost some weeks back was in response to the suggestion that TV delivery could be restricted to DSat, Which in this case would not be true as the final leg would still rely upon a terrestrial transmitter (or small groups of transmitters) (regardless as to who funds and operates them)
The trouble is, with an industry-led approach, consumers are unlikely to pay the initial high costs without the content to match. And unless that content becomes widely available, AND enthuses the consumers (i.e. it has to be demonstrably better than broadcast HD or blu-ray within the confines of a domestic viewing environment) then it is always likely to remain a niche (and premium) product. And even with strong high-street sales of 4K sets (driven by manufacturers flooding the market at the expense of existing sets, aka "manufacturer-led demand") it still needs that killer app (again demonstrably better than current broadcast HD or blu-ray) consumers will simply be buying them because there is little choice.
So it still delivers the signal via a terrestrial transmitter network!
Good point.
Its exactly what happened with HD though. Most new tv's became HD ready although there was no content. It was only about 1-2 years after tv's went HD that HD became available over broadcast.
I think you are right though in so far as what will drive sales will be 4K video games and next generation BluRay Discs with 4K content.
There is a very visible advantage to 4K you can see on the better 4K videos on Youtube.
However, 4K on Terrestrial, not likely to happen. DTT has no room for any more HD never mind 4K which is 4X as many pixels.
The way forward is satellite and internet athough personally I have several issues with the latter. Terrestrial is finished.
8K will probably be the next big thing. 4K is something the manufacturers would like to sell to everyone in the meantime to keep a steady flow of income from early adopters.
8K won't be here until around 2020 and there's no way of broadcasting it even it arrived earlier as the UK doesn't have the means to do it.
I have a sneaking feeling that 4K and 8K per se will be passed over in favour of OLED technology (as a means of driving manufacturing revenue streams as well as being a must-have product).
And in that respect, DTT has plenty of life in it.
A move to DVB-T2 will allow many more HD channels, even if no more spectrum is made available. And that's simply using existing technology. There's a recent thread in this forum discussing that sort of thing:
A move to DVB-T2 will allow many more HD channels, even if no more spectrum is made available. And that's simply using existing technology. There's a recent thread in this forum discussing that sort of thing:
That's using AVC. It's not a massive stretch to predict that HEVC will allow a DVB-T2 mux to broadcast two, perhaps three, 4K channels if receivers become available. That's not dissimilar to HD when it was introduced on Freeview.
Why are they even considering using RF to distribute UHD signals? Surely the economics of it mean that Multicast Superfast Broadband is the obvious medium to distribute these channels to the home in future.
Exactly, it's not ready but will be in a few years. A window of opportunity for the manufacturing industry to sell the 4K kit it will make obsolete.
Thats always the way with everything.
Are you going to wait at least 7 years until 2020 in case the 4K tv you could buy in 2014 became obsolete in 6 years?
I could almost guarantee that by the time SuperHiVis arrives in 2020, there will be a replacement technology for it on the horizon. No matter what you buy, the shelf life will only be 5-6 years, thats the nature of tech,
I have a sneaking feeling that 4K and 8K per se will be passed over in favour of OLED technology (as a means of driving manufacturing revenue streams as well as being a must-have product).
And in that respect, DTT has plenty of life in it.
A move to DVB-T2 will allow many more HD channels, even if no more spectrum is made available. And that's simply using existing technology. There's a recent thread in this forum discussing that sort of thing:
Are you going to wait at least 7 years until 2020 in case the 4K tv you could buy in 2014 became obsolete in 6 years?
I could almost guarantee that by the time SuperHiVis arrives in 2020, there will be a replacement technology for it on the horizon. No matter what you buy, the shelf life will only be 5-6 years, thats the nature of tech,
Ultimately it will be constrained by the size of houses / rooms. There will be little point in continually upgrading to the point where everyone would need their own personal aircraft hangar to accommodate the tv.
The use of the 600mhz band is only temporary. I understand its likely to be withdrawn again in 2018 presumably causing the loss of all added channels.
It will be temporary if it is required as a replacement for the 700MHz band, 2018 is the earliest it could be required. The additional multiplex licences could extend until 2026, if so, they would expire at the same time as the existing COM mux licences. It's debatable which channels would then survive on newly licensed multiplexes.
The use of the 600mhz band is only temporary. I understand its likely to be withdrawn again in 2018 presumably causing the loss of all added channels.
However as stated by jj20x above, It will be temporary if it is required as a replacement for the 700MHz band.
Furthermore, if you read that first PDF document from the BBC, Channel 4 and Arqiva - they are proposing to use this as a way of promoting the uptake of DVB-T2 and HD kit, with a longer-term view of transitioning to DVB-T2.
Once that has taken place it is far easier to convert one or mux existing muxes to DVB-T2 (thus providing additional capacity within those muxes).
The joint submission from BBC, Channel 4, ITV and Arqiva to Ofcom’s March 2012 consultation “Securing long term benefits from scarce spectrum resources - A strategy for UHF bands IV and V” identified the role that interim use of 600 MHz could play in facilitating the transition of DTT to DVB-T2 and High Definition (HD).
<snipped>
To ensure that the platform can continue to provide the range of services that viewers have come to expect from DTT, in the event that 700 MHz is cleared in the future, it will be necessary to transition the network to DVB-T2. This will require many viewers to obtain some combination of new TVs, aerials or set-top boxes.
To minimise the costs and disruption (to consumers, Government and industry), any transition should initially be consumer led. To support this process the BBC, Channel 4 and Arqiva have developed a proposal to invest in additional TV services for viewers to encourage them to make the transition through launching two additional DTT multiplexes in the 600 MHz band.
You do need to visit this forum more often, as this has been the subject of a number of discussions here (and in the Broadcasting forum).
It will be temporary if it is required as a replacement for the 700MHz band, 2018 is the earliest it could be required. The additional multiplex licences could extend until 2026, if so, they would expire at the same time as the existing COM mux licences. It's debatable which channels would then survive on newly licensed multiplexes.
If the government can make some money out of auctioning it you can guarantee that it will only be temporary.
Across Europe I think there will be more calls to reassign 700MHz to other uses than to keep it for TV as TV moves to other mediums.
Furthermore, if you read that first PDF document from the BBC, Channel 4 and Arqiva - they are proposing to use this as a way of promoting the uptake of DVB-T2 and HD kit, with a longer-term view of transitioning to DVB-T2.
Once that has taken place it is far easier to convert one or mux existing muxes to DVB-T2 (thus providing additional capacity within those muxes).
DVB-T2 isn't going to provide enough bandwidth to have any great impact from what I can see. It provides a 30-50% increase in efficiency according to here:
In the best case scenario, ie at 50% that would allow 1.5 times the channels there are now on Freeview (without 600mhz).
As there are currently 4HD channels on Freeview that allows for 6 plus 1/2 as many again of the SD channels. . If you chose more HD over SD channels, then at Full HD you could have a few more HD channels at the expense of SD.
However, look at the full scenario.
1x 4K channel = 4x as many pixels as Full HD. That's potentially 4x as much bandwidth, although in actuality, its likely to be less. So your 6 HD channels would allow potentially 1x 4K transmission plus probably 2-3 HD channels or 2x 4K and maybe 1 x HD channels.
Not much future in that as I see it with many more channels likely to be going HD and some channels likely to be going 4K.
Another example is 3D is here to stay. 4K could easily head down the 3D route increasing bandwidth further.
Also, looking further forward, theres SuperHiVis at 8K which is 16X full HD (not 8x).
So if you said 1 SuperHVis requires 12x the bandwidth (shear guess based on 16), then where's the bandwidth going to come from?
DTT is short of space and its only going to get worse in the future as I see it as a sell off of the loaned 600mhz space is likely. Codecs improvements may provide more space but they're not likely to keep up with the hungry bandwidth requirements of future technologies.
More channels could be gained by reductions in quality, but do you really want lower picture quality as well?
If the government can make some money out of auctioning it you can guarantee that it will only be temporary.
Across Europe I think there will be more calls to reassign 700MHz to other uses than to keep it for TV as TV moves to other mediums.
It depends how much demand there is from the phone companies for this range. The longer distance of this range is better suited to rural usage where demand isn't so high. Capacity is more limited in more densely populated urban areas, which would be better served by smaller cells at a higher frequency range.
The cash from the last auction fell well below the amount the Government had expected. If they now have enough bandwidth to meet their needs for rural coverage, they are unlikely to bid large amounts of cash, if they bid at all.
DTT is short of space and its only going to get worse in the future as I see it as a sell off of the loaned 600mhz space is likely. Codecs improvements may provide more space but they're not likely to keep up with the hungry bandwidth requirements of future technologies.
The Government already tried to clear 600MHz for the "digital dividend" and discovered there isn't actually a market for it. So they won't be selling that, just refarming it with DTT channels displaced from the 700MHz range, assuming they actually sell that range.
DVB-T2 with MPEG-4 isn't really suitable for 4K or 8K but MPEG-4 will eventually be replaced with more efficient standards such as HEVC. HEVC is in its infancy and will most likely be improved with later releases.
It is worth remembering that DVB-T/MPEG-2 didn't really have sufficient bandwidth for HD. The DVB-T2 standard was agreed just in time to allow for the current HD channels to be given their own multiplex. Perhaps DVB-T3 or even DVB-T4 will be around by the time 8K becomes a reality.
You say that 3D is here to stay. It possibly is but will most likely remain a niche market. The BBC certainly seem to be putting their faith in 8K rather than 3D.
Comments
"Takes barely any more"? The question is this: at a given bitrate (especially one that's likely to be broadcast), can you deliver appreciably better quality using 1080p50 than 1080i50 to a modern TV using a decent H.264 encoder?
If not, then talk of 1080p50 is pointless.
In practice, the results are content, bitrate and encoder dependent, giving the answer: sometimes yes, sometimes no.
It help MPEG-2 to deliver better quality at a lower bitrate. That is the opposite of inefficient. Last time I checked, MPEG-2 was digital
FWIW it also helped raw uncompressed digital video maintain better quality at a given bitrate for over 20 years. In this realm (where broadcasters work) dumping interlacing means doubling the bitrate for far less than a doubling in quality. It you want to jump from interlaced to progressive without doubling the bitrate during production, you have to jump from 1080i to 720p. The drop in static resolution is easily visible if you do.
The results of such tests are dependent on bitrate, encoder capabilities, content, and the display used.
It is true that interlacing can make no sense at all as a pre-process to an optimal video codec feeding a progressive display. However, video codecs are not optimal, and while some of the test results and demos appear conclusive, with real-world encoders and usage the situation is not nearly so clear cut.
(There have been demos where the protagonists have used an encoder that doesn't handle interlaced content properly to prove how much better progressive is, and demos where people have showed that 1280x720p is better (or at least never worse) than 1920x1080i on displays that only had 1366x768 pixels!)
1080i > 1080p is nowhere near enough of a night-and-day difference to justify upgrading the entire chain in one go. You can get so close with half-decent bitrates, decent encoders, and decent deinterlacers.
Beware that some of those who promote progressive encoding need it to crank the bitrate down (which is easier with progressive H.264). You can imagine where this path leads.
Cheers,
David.
Right. Depends on the source material I guess. For fast action shots or any scene where interlacing artefacts can appear then yes. For near-stationary scenes, 1080i is essentially 1080p anyway. But then when less things are changing on-screen, less bits are required anyway (assuming VBR). The major benefits will come during scenes where high bandwidth is needed, and that's where 1080p wins.
I don't know much about MPEG2 so I'm happy to concede that MPEG2 wasn't that affected by prediction being harder when interlaced material is encoded. It is presumably more difficult for the advanced prediction techniques of AVC to work with interlaced material, so some of the benefit is lost. Interlacing works great in the analogue world but it doesn't work very well with modern digital compression. That won't change either, with HEVC being designed for progressive sources only.
For uncompressed video, sure. It's only digital compression that doesn't cope that well with interlaced material.
Perhaps. I would love to see some actual 1080p/50 broadcasts that can be compared with 1080i/25 broadcasts, especially when using the same statistical muxing.
Oh I know no-one's going to pay to upgrade entire chains. This is more about what should've been done in the first place but never mind - it seems that 4K or whatever it'll be called will be entirely progressive.
Also, it's hard to say that anyway. Where is the 1080p/50 material we can use to compare at home?
A lot of, ahem, "scene" releases encode 1080i/25 to 720p/25 to save on file size. iPlayer does the same. I am totally against this. I would much rather a 720p/50 file be a bit bigger, or, even better, just keep the original 1080i/25 file. That's what I do with my recordings.
I did some research and found that the proposal by Cossor (who were Britain's leading pre-war set maker) was for 525-lines/50Hz.
I had a feeling that might be the case but didn't want to claim it as fact until I read it somewhere else.
Television line systems were all over the place between 1945 and 1950 and so not to be confused with the later CCIR and NTSC standards.
I would disagree.
Many reports say 4K tv is set to be the next big thing as 3D hasn't sold as many new sets as manufacturers anticipated so it looks very much as though all new tv's will become 4K as standard just as all new tv's became HD.
4K is currently very expensive but was so was HD when it 1st came out. I remember 42" sets being £8,000. Now you can get one for a couple of hundred.
Also many PC games are going 4K with 4K monitors set to introduce 4K to the masses when prices fall.
There are ways around that for black spots eg to have a local relay where the signal is received by dish and then converted to DTT and re-transmitted via an ordinary aerial mounted on a pole.
This already happens with DTT now eg this is a DTT relay transmitter, little more than a pole and cluster of aerials.
http://www.aerialsandtv.com/_wp_generated/wp36808257_01_06.jpg
As for buildings that are subject to Listings etc, its usually possibly to have a hidden dish in the garden. That's what many listed buildings have currently.
PS don't visit this part of the forum very often so apologies if someone has already covered this - couldn't read 5+pages of replies!
So it still delivers the signal via a terrestrial transmitter network!
Good point.
I suspect most people with 4K sets will watch material upscaled from lower definition the same way "HDTV ready" owners do now.
Assuming it isn't the red herring that 3D turned out to be then Sky will be the main beneficiary as it will always be able to offer a far wider choice of 4K programming than terrestrial TV.
Sorry to be a pedant, but HEVC was designed for and handles interlace just fine (as you've mentioned in a previous post); 4K/8K UHD standards don't support it however, but you can guarantee a 4K TV will still handle interlace anyway...
The thing that I'm having the biggest issue with in terms of interlace vs progressive is that surely all of the cameras used to record HD footage are now progressive, so why convert it to a legacy format and lose 50% of the vertical resolution? In order to encode it the interlaced content will invariably be reconstructed into a full frame for reference! I'd prefer a more detailed frame and let my telly do some interpolation - it does a pretty good job of "24p" BDs.
As for those 720p "releases" you mentioned, they're fine for a phone/small tablet...
8K will probably be the next big thing. 4K is something the manufacturers would like to sell to everyone in the meantime to keep a steady flow of income from early adopters.
Not through the transmitter network, through self-help relays funded and operated by the local community.
That's true, however my original ppost some weeks back was in response to the suggestion that TV delivery could be restricted to DSat, Which in this case would not be true as the final leg would still rely upon a terrestrial transmitter (or small groups of transmitters) (regardless as to who funds and operates them)
Its exactly what happened with HD though. Most new tv's became HD ready although there was no content. It was only about 1-2 years after tv's went HD that HD became available over broadcast.
I think you are right though in so far as what will drive sales will be 4K video games and next generation BluRay Discs with 4K content.
There is a very visible advantage to 4K you can see on the better 4K videos on Youtube.
However, 4K on Terrestrial, not likely to happen. DTT has no room for any more HD never mind 4K which is 4X as many pixels.
The way forward is satellite and internet athough personally I have several issues with the latter. Terrestrial is finished.
8K won't be here until around 2020 and there's no way of broadcasting it even it arrived earlier as the UK doesn't have the means to do it.
I see, it's difficult keeping track of all the many different paths this thread has branched off into.
Exactly, it's not ready but will be in a few years. A window of opportunity for the manufacturing industry to sell the 4K kit it will make obsolete.
And in that respect, DTT has plenty of life in it.
Erm, yes it does:
http://stakeholders.ofcom.org.uk/binaries/consultations/uhf-strategy/responses/BBC_Channel_4_Arqiva.pdf
http://stakeholders.ofcom.org.uk/consultations/600mhz-award/summary
A move to DVB-T2 will allow many more HD channels, even if no more spectrum is made available. And that's simply using existing technology. There's a recent thread in this forum discussing that sort of thing:
http://forums.digitalspy.co.uk/showthread.php?t=1804890
Also note that 4K is possible over Freeview now:
http://recombu.com/digital/news/4k-ultra-hd-via-freeview-hd-tech-tested-at-mwc-2013_M11239.html
That's using AVC. It's not a massive stretch to predict that HEVC will allow a DVB-T2 mux to broadcast two, perhaps three, 4K channels if receivers become available. That's not dissimilar to HD when it was introduced on Freeview.
Thats always the way with everything.
Are you going to wait at least 7 years until 2020 in case the 4K tv you could buy in 2014 became obsolete in 6 years?
I could almost guarantee that by the time SuperHiVis arrives in 2020, there will be a replacement technology for it on the horizon. No matter what you buy, the shelf life will only be 5-6 years, thats the nature of tech,
The use of the 600mhz band is only temporary. I understand its likely to be withdrawn again in 2018 presumably causing the loss of all added channels.
Ultimately it will be constrained by the size of houses / rooms. There will be little point in continually upgrading to the point where everyone would need their own personal aircraft hangar to accommodate the tv.
http://recombu.com/digital/news/what-is-super-hi-vision-shv-ultra-high-definition_M10844.html - scroll down to see a rather large tv. :eek:
It will be temporary if it is required as a replacement for the 700MHz band, 2018 is the earliest it could be required. The additional multiplex licences could extend until 2026, if so, they would expire at the same time as the existing COM mux licences. It's debatable which channels would then survive on newly licensed multiplexes.
However as stated by jj20x above, It will be temporary if it is required as a replacement for the 700MHz band.
Furthermore, if you read that first PDF document from the BBC, Channel 4 and Arqiva - they are proposing to use this as a way of promoting the uptake of DVB-T2 and HD kit, with a longer-term view of transitioning to DVB-T2.
Once that has taken place it is far easier to convert one or mux existing muxes to DVB-T2 (thus providing additional capacity within those muxes).
You do need to visit this forum more often, as this has been the subject of a number of discussions here (and in the Broadcasting forum).
If the government can make some money out of auctioning it you can guarantee that it will only be temporary.
Across Europe I think there will be more calls to reassign 700MHz to other uses than to keep it for TV as TV moves to other mediums.
DVB-T2 isn't going to provide enough bandwidth to have any great impact from what I can see. It provides a 30-50% increase in efficiency according to here:
http://www.dvb.org/technology/dvbt2/index.xml
In the best case scenario, ie at 50% that would allow 1.5 times the channels there are now on Freeview (without 600mhz).
As there are currently 4HD channels on Freeview that allows for 6 plus 1/2 as many again of the SD channels. . If you chose more HD over SD channels, then at Full HD you could have a few more HD channels at the expense of SD.
However, look at the full scenario.
1x 4K channel = 4x as many pixels as Full HD. That's potentially 4x as much bandwidth, although in actuality, its likely to be less. So your 6 HD channels would allow potentially 1x 4K transmission plus probably 2-3 HD channels or 2x 4K and maybe 1 x HD channels.
Not much future in that as I see it with many more channels likely to be going HD and some channels likely to be going 4K.
Another example is 3D is here to stay. 4K could easily head down the 3D route increasing bandwidth further.
Also, looking further forward, theres SuperHiVis at 8K which is 16X full HD (not 8x).
So if you said 1 SuperHVis requires 12x the bandwidth (shear guess based on 16), then where's the bandwidth going to come from?
DTT is short of space and its only going to get worse in the future as I see it as a sell off of the loaned 600mhz space is likely. Codecs improvements may provide more space but they're not likely to keep up with the hungry bandwidth requirements of future technologies.
More channels could be gained by reductions in quality, but do you really want lower picture quality as well?
It depends how much demand there is from the phone companies for this range. The longer distance of this range is better suited to rural usage where demand isn't so high. Capacity is more limited in more densely populated urban areas, which would be better served by smaller cells at a higher frequency range.
The cash from the last auction fell well below the amount the Government had expected. If they now have enough bandwidth to meet their needs for rural coverage, they are unlikely to bid large amounts of cash, if they bid at all.
The Government already tried to clear 600MHz for the "digital dividend" and discovered there isn't actually a market for it. So they won't be selling that, just refarming it with DTT channels displaced from the 700MHz range, assuming they actually sell that range.
DVB-T2 with MPEG-4 isn't really suitable for 4K or 8K but MPEG-4 will eventually be replaced with more efficient standards such as HEVC. HEVC is in its infancy and will most likely be improved with later releases.
It is worth remembering that DVB-T/MPEG-2 didn't really have sufficient bandwidth for HD. The DVB-T2 standard was agreed just in time to allow for the current HD channels to be given their own multiplex. Perhaps DVB-T3 or even DVB-T4 will be around by the time 8K becomes a reality.
You say that 3D is here to stay. It possibly is but will most likely remain a niche market. The BBC certainly seem to be putting their faith in 8K rather than 3D.
http://www.3dfocus.co.uk/3d-news-2/ultra-hd/bbc-favours-super-hi-vision-over-3d/10293