# The BBC is developing 100Hz high framerate TV (sorta)



## qubit (Feb 26, 2019)

We've benefitted from 100Hz+ framerates on the PC for years and it's about time this came to TV, too. This can't come soon enough and if they could lose the annoying interlace, ie progressive scan, that would be even better, but I doubt they will, since it will double the bandwidth required.

There don't seem to be any recent developments though, the latest being 2017, so it's not very encouraging.



> A lot of aspects of the technology behind a television system have changed over the decades, since the introduction of monochrome 405-line systems in 1936, to the switch-over to digital TV across the UK in 2012. However, one aspect of the TV systems that has ironically remained “static” is the frame rate, where it has remained at 25 frames per second (fps or Hz). Interlacing is used for the majority of our broadcasts, where only the even or odd lines (fields) of a frame are sent, at a rate of 50 *fields* per second.  This effectively doubles the temporal resolution, but even at the conventional field rate of 50 fields per second, motion blur and judder are very much apparent on video where there is lots of motion, such as with sports content.  With higher frame rates (100fps or higher), motion blur is significantly reduced, producing sharper images, which provides a much more natural and immersive viewing experience. An illustration of the motion blur improvements at higher frame rates is shown below.



BBC R&D


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## lexluthermiester (Feb 26, 2019)

qubit said:


> We've benefitted from 100Hz+ framerates on the PC for years and it's about time this came to TV, too. This can't come soon enough and if they could lose the annoying interlace, ie progressive scan, that would be even better, but I doubt they will, since it will double the bandwidth required.
> 
> There don't seem to be any recent developments though, the latest being 2017, so it's not very encouraging.
> 
> ...


I wish the US would do something similar, like 120hz broadcasts.


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## dorsetknob (Feb 26, 2019)

Not up on tv's but 
don't they already sell 240Hz TV's ( But no broadcast support ) in High end models.


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## lexluthermiester (Feb 26, 2019)

dorsetknob said:


> Not up on tv's but
> don't they already sell 240Hz TV's ( But no broadcast support ) in High end models.


They do, but the reality is that very few screen are actually 240+hz. Most are 120hz and implement some form of frame blanking and or blending method to trick the human eye.


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## Ferrum Master (Feb 26, 2019)

Taxpayer money? This is weird really coming from BBC...


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## las (Feb 26, 2019)

Yes, bandwidth is the biggest problem here. I'd love higher native Hz on TV's.


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## dorsetknob (Feb 26, 2019)

Ferrum Master said:


> Taxpayer money? This is weird really coming from BBC...


Not so strange when you consider that the whole TV infrastructure in the UK Stems from Circa 1936
with the BBC  which was the  sole Developer and Broadcaster.
Yes its Tax payer Money invested in this and if it works and is commercially Viable then the BBC (and the Tax payer) will enjoy the financial benefits from the subsequent IP


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## notb (Feb 26, 2019)

?
High frequency movies and television are already here. I don't really get what's so special about this news.
This may have been "news" in 2014. But today?


lexluthermiester said:


> I wish the US would do something similar, like 120hz broadcasts.


This article is about technology for recording, not broadcasting (i.e. terrestrial TV).
Video (sport, movies, TV programs or whatever) can be recorded at higher framerates and they already are.
You may benefit from this if you watch them via the Internet.

Broadcasting is something entirely different. It's meant to be a fairly stable, "fallback" technology. Every major change is a huge event and effort.


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## qubit (Feb 26, 2019)

notb said:


> High frequency movies and television are already here. I don't really get what's so special about this news.
> This may have been "news" in 2014. But today?


It's still stuck at 50Hz in the UK and 60Hz in the US. How can you not know something so basic? If you read the article I've linked to, it will clarify this, too. I didn't post this as a news article either, but as a talking point.


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## dorsetknob (Feb 26, 2019)

qubit said:


> It's still stuck at 50Hz in the UK and 60Hz in the US.


+ the Rest of the World 
Pal/Secam = 50Hz
NTSC =60Hz
ATSC = 60Hz


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## lexluthermiester (Feb 26, 2019)

notb said:


> This article is about technology for recording, not broadcasting (i.e. terrestrial TV).


I think you'll find that it is if you read the article. Even the quote mentioned OTA broadcasts.


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## silentbogo (Feb 26, 2019)

It's been technically possible since T2 introduction, so what I think is happening is that BBC is starting a public demand/acceptance campaign, so it'll be easier to make 100Hz broadcasts an actual standard (read - softening bureaucratic process).
DVB-T2 in its latest revision can do HEVC, and the bandwidth is high enough to accomodate compressed FHD 100Hz stream with some pipes to spare.
Though, it will require hardware upgrades on both ends: e.g. expensive HEVC encoders on the broadcast center's end, and latest DVB-T2 boxes w/ HEVC support on the user's end (most of the mainstream hardware can barely do 1080p in x264 due to cost savings on the SoC).

Plus, it's gonna be the same opinion split as we have on PC: do we need higher framerate or higher resolution...
Personally I doubt 100Hz will catch up. The only reason most people saw the difference between "old" and "new" tech in BBC demo is because they were comparing progressive@100Hz to interleaved@50Hz, which is definitely not "apples-to-apples", and definitely outside the scope of just the framerate.


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## notb (Feb 26, 2019)

lexluthermiester said:


> I think you'll find that it is if you read the article. Even the quote mentioned OTA broadcasts.


No, it doesn't. The whole article is about future video standards, not about broadcasting.

The quote from first post is about historical reasons for 25Hz. And the historical reasons are: because TV was using analog signal, everything had to be unified.
I assume we all know BBC is producing content, not building transmitter towers.
Paragraph "the future" mentions BT.2020 which is, again, a standard for content, not broadcasting.


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## dorsetknob (Feb 26, 2019)

notb said:


> I assume we all know BBC is producing content, not building transmitter towers.


The BBC has most of the Infrastructure needed ie Towers /studio's
This is about Developing the Broadcast HARDWARE to put on the Existing Towers and to upgrade the Studio's


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## Vayra86 (Feb 26, 2019)

Pointless exercise if you lack high FPS content beyond sports, and the market really doesn't ask for any of this at all anyway. Even resolution is an afterthought, the vast majority is perfectly satisfied with 1080i/50 on a 4K HDTV, go figure...

I like the push forward, but as pointed out in the original article, this does already seem to have come to a halt. The bottleneck is still there, and it is infrastructure that needs to change. Formats and quality will then follow simply through the push of the market. They already are with ondemand services like Netflix, fiber to the home/area and similar developments. I have more faith in better compression methods on the digital highway than I have in development on the archaic regular broadcasting agenda.


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## qubit (Feb 26, 2019)

Everyone, I've changed the thread title slightly to better reflect the lack of progress in this upgrade.


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## FordGT90Concept (Feb 26, 2019)

lexluthermiester said:


> I wish the US would do something similar, like 120hz broadcasts.


Wish granted: ATSC 3.0 is going to support up to 120 Hz.


> 6.2.3.1 Progressive Video Formats
> • The spatial resolution shall be constrained to not more than 2160 lines and 3840 horizontal pixels.
> • The spatial resolution in both dimensions shall be evenly divisible by 8.
> • *The picture rate in 60 Hz regions shall be one of the following in Hz: 24/1.001, 24, 30/1.001, 30, 60/1.001, 60, 120/1.001, 120.*
> ...


How much content will actually use 120 fps?  Virtually none.  Avatar is like the only thing using 60 fps.

Edit: the 1.001 is intentional and goes back to adding color data to 60 Hz signal.  Here's the list in decimal rounding:

23.98
24
29.97
30
59.94
60
119.88
120
Most movies are broadcast over ATSC 1.0 at 24 fps, TV programs are 29.97.

Refresher:


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## droopyRO (Feb 26, 2019)

Someone was watching a YT video last year, she called me to ask why is the video on fast forward. I looked at it for two seconds and said, that it is not, probably running at 60 fps. Right clicked the video and it was running at that framerate. Imagine the shock most people would have if TV was at 120Hz/fps


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## phanbuey (Feb 26, 2019)

droopyRO said:


> Someone was watching a YT video last year, she called me to ask why is the video on fast forward. I looked at it for two seconds and said, that it is not, probably running at 60 fps. Right clicked the video and it was running at that framerate. Imagine the shock most people would have if TV was at 120Hz/fps



There's tv's that autofill and do that, it looks weird as hell.


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## SoNic67 (Feb 28, 2019)

It is stupid. All the "HDTV" produced are in fact computers with LCD panels. Majority of the computer monitors are running at 60Hz or multiples thereof.
Why would anyone create a new "standard" at 100Hz when you have nothing to support that in terms of infrastructure?
Just leave the analog to go in the history and don't tie the 4K pure digital TV to those old ideas. Make 60Hz progressive everywhere in the digital TV world.

PS: Why was 50 Hz in EU and 60 Hz in US? Because in the beginning the vertical refresh was derived from the power frequency, it was too hard to extract the syncro from TV signal. However in the 50's this was already possible, so the relation to the mains frequency was not needed per se. That's why NTSC could "shift it" a little bit (by 1001/1000), to mask the color carrier.


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## FordGT90Concept (Feb 28, 2019)

SoNic67 said:


> It is stupid. All the "HDTV" produced are in fact computers with LCD panels. Majority of the computer monitors are running at 60Hz or multiples thereof.
> Why would anyone create a new "standard" at 100Hz when you have nothing to support that in terms of infrastructure?
> Just leave the analog to go in the history and don't tie the 4K pure digital TV to those old ideas. Make 60Hz progressive everywhere in the digital TV world.


Interlaced uses half of the bandwidth of progressive.  Even if bandwidth isn't a problem going forward, there's a lot of legacy content that is interlaced so for the sake of backwards compatibility, interlaced is still supported.



SoNic67 said:


> PS: Why was 50 Hz in EU and 60 Hz in US? Because in the beginning the vertical refresh was derived from the power frequency, it was too hard to extract the syncro from TV signal. However in the 50's this was already possible, so the relation to the mains frequency was not needed per se. That's why NTSC could "shift it" a little bit (by 1001/1000), to mask the color carrier.


Backwards compatibility again.  Consider that it is still possible to use ATSC to NTSC converter boxes.  Not changing anything in regards to how broadcasts work make it really easy to convert.  Even with ATSC being mandatory since 2009, most digital TV series are filmed and broadcast in 29.97.

The video I linked explains it all in detail.


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## SoNic67 (Feb 28, 2019)

FordGT90Concept said:


> legacy content that is interlaced so for the sake of backwards compatibility


WHY? Why broadcast that content interlaced, and interlace the progressive content in this process, instead of doing the other way around? Brodacast everthing progressive. With the advent of H264 and H265, and with 256QAM modulation, there is enough bandwidth for progressive 60Hz. Maybe drop at 24Hz for movies, to use less compression, and let user equipment deal with it. Why imposing a fix framerate today?
Any HDTV today has the technology to play it either at native 24Hz (usually expensive sets) or up-converted to 48, 60, 120 or whatever user desires.
There is nothing they need to keep compatibility with. If there are some poor folks that still use CRT's, they can buy converters. In US those costed $20-50 when transition happened in 2009 (a decade ago!),abd the FCC gave a rebate back up to $50. Now those converters are in every thrift shop for like $3-5 or probably thrown in garbage. Nobody has CRT's anymore, you can't even donate them for free. I

IMO it's more that the BBC is stuck in the past with a stupid nostalgia. They transitioned to full digital in 2008/2012, but keep ordering purchasing expensive custom 50Hz equipment (cameras) when a transition to 60Hz would be so easy and so beneficial for everyone. Cheaper too, 60Hz equipment being mass produced and only after that customized for 50Hz.
Right now every "HDTV" in EU "blinks" at 50 FPS instead of 60FPS like the rest of your computer monitors and cell phones/tablets. Is there any video content you can't see on those 60Hz devices because it is at a different framerate? The modern HDTV's are nothing but huge tablets with associated CPU and GPU (ARM family usually).


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## qubit (Feb 28, 2019)

SoNic67 said:


> WHY? Why broadcast that content interlaced, and interlace the progressive content in this process, instead of doing the other way around? Brodacast everthing progressive. With the advent of H264 and H265, and with 256QAM modulation, there is enough bandwidth for progressive 60Hz.


One word: money. They can still squeeze in twice the number of channels for a given bandwidth, hence twice the money to be made. Unless bandwidth becomes infinite one day (unlikely) interlaced scanning is here to stay.


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## TheoneandonlyMrK (Feb 28, 2019)

lexluthermiester said:


> I wish the US would do something similar, like 120hz broadcasts.


I wish someone would finish the job and release this in the Uk


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## SoNic67 (Feb 28, 2019)

US still fights with MPEG-2 for terrestrial encoding, 1080i and 720p: https://en.wikipedia.org/wiki/ATSC_standards#Video
But at least they recognized the need to allow multiple framerates and resolutions. Low framerates in studio transmissions (low compression, superb picture) and higher framerates in sports (lower resolution, higher compression).
In theory, television stations in the U.S. are free to choose any resolution, aspect ratio, and frame/field rate, within the limits of Main Profile @ High Level. Many stations do go outside the bounds of the ATSC specification by using other resolutions – for example, 352 x 480 or 720 x 480. But, in my experience, if is not HD... nobody watches it.
The maximum bit rate value in the sequence header of the MPEG-2 video stream is 19.4 Mbit/s for broadcast television, and 38.8 Mbit/s for the "high data rate" mode (e.g., cable television).

PS: ATSC 3.0 (broadcast experimental since 2016) adds 4K resolutions.


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## FordGT90Concept (Feb 28, 2019)

They choose MPEG-2 for two reasons:
1) it had broad use with DVD so ASIC decoders and encoders were already widely available.
2) it has a lot of error recovery capability (e.g. to recover from scratches on discs) which is an absolute necessity with terrestrial broadcasts.

ATSC 3.0 rollout is going to be very expensive for everyone (producers, distributors, broadcasters, and consumers).  It's coming, but slowly.

As you pointed out, 20ish Mb/s isn't much.  A single 4K channel is going to need at least 30 Mb/s with HEVC and that's interlaced at 25 fps.  They need about 80 Mb/s for 29.97 fps 4:4:4 progressive scan 4K on HEVC.  And how many devices can even handle decoding that?


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## SoNic67 (Feb 28, 2019)

Prices for ASIC hardware capable of playing 4K h265 dropped a lot. Heck, even Raspberry Pi 3+ (or a decent clone) can do it. Chromecast 4k, Amazon TV 4k, Roku 4k... That's similar with what is inside of a  4k TV now.
Encoding and editing the video in studio will be done on less compressed formats, like is done today.


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## FordGT90Concept (Feb 28, 2019)

There's different profiles and tiers.

ATSC 3.0 does...


Name|Profile|Level|Tier|Max FPS|Color|4:2:0|4:2:2|4:4:4
Legacy SD|Main 10|3.1|Main|60|Rec. 709|10 Mb/s|15 Mb/s|20 Mb/s
Interlaced HD|Main 10|4.1|Main|60|Rec. 709|20 Mb/s|30 Mb/s|40 Mb/s
Progressive|Main 10|5.2|Main|120|Rec. 2020|60 Mb/s|90 Mb/s|120 Mb/s
Most devices already support decoding of Main 10, Level 4.1 which is partly why they selected it.  Support for 5.2 is common on 4K devices.  The huge expense is on the encoding side.


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## AsRock (Feb 28, 2019)

Ferrum Master said:


> Taxpayer money? This is weird really coming from BBC...



Probably want to add some thing to it so it phones home, as one thing the BBC is good for is abusing the law.


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## Ferrum Master (Feb 28, 2019)

AsRock said:


> Probably want to add some thing to it so it phones home, as one thing the BBC is good for is abusing the law.



Looking at their FB page, they are abusing everything there...  instead of doing things that they should not, could invest into more quality content.

Also... here the whole thing is done by carriers and telecom companies, all the programs and development, fight for the customer. They compete with each other, so better product develops. Why taxpayer money should be used to develop the obvious?

Is it DVB, cable, mobile network... that's not the problem, the content is... as some mentioned, sports is the only one needing high resolution, high FPS technology, you have to see the damn puck.

It's more like rubbish article with a meaning - you see we are working.


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## FordGT90Concept (Feb 28, 2019)

Isn't BBC a lot like RT?  Russia keeps RT around because it is part of their propaganda machine.  Which begs the question why has the BBC not been spun off into a private organization?  Looking at the Wikipedia article on it, all I see is alarm bells.  It's the Queen's propaganda machine.

The push to HD was motivated by clearing RF bandwidth that analog occupied.  There's no overarching, inherent motivation to move to 4K like HD.


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## qubit (Mar 1, 2019)

FordGT90Concept said:


> Isn't BBC a lot like RT?  Russia keeps RT around because it is part of their propaganda machine.  Which begs the question why has the BBC not been spun off into a private organization?  Looking at the Wikipedia article on it, all I see is alarm bells.  It's the Queen's propaganda machine.
> 
> The push to HD was motivated by clearing RF bandwidth that analog occupied.  There's no overarching, inherent motivation to move to 4K like HD.


They’re certainly the government’s mouthpiece. Can’t say much more or we’ll stray into politics.

There are already 4K Freeview test transmissions if I remember correctly, but a commercial rollout isn’t anytime soon.


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## FordGT90Concept (Mar 1, 2019)

Yeah, a few stations in the USA are broadcasting ATSC 3.0 already for testing purposes but good luck finding an ATSC 3.0 tuner.


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