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4k TV on Freesat or Freeview?



 
 
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  #11  
Old August 3rd 15, 06:47 PM posted to uk.tech.digital-tv
Michael Chare[_5_]
external usenet poster
 
Posts: 64
Default 4k TV on Freesat or Freeview?

On 03/08/2015 19:22, _Unknown_Freelancer_ wrote:


FTR, I live right next to a major BT exchange.
There isnt even a cabinet between me and the exchange.
I get 13Mb/s!! (twisted pair phone line)
As I said previously, to get decent bandwidth to the home requires either
fibre or co-ax.
.....not a lot of that about, and in some areas, just aint gonna happen.


As far as home connections are concerned, unfortunately BT are
determined to use early 20th century technology. The Internet speed to
my house by metal phone line is about a 10th of what you have.
Fortunately I have a real fibre connection (not what BT call fibre)
which runs 10 times faster than you have.


--
Michael Chare
Ads
  #12  
Old August 3rd 15, 07:12 PM posted to uk.tech.digital-tv
Paul Ratcliffe
external usenet poster
 
Posts: 2,486
Default 4k TV on Freesat or Freeview?

On Mon, 3 Aug 2015 19:22:14 +0100, _Unknown_Freelancer_ /dev/null wrote:

The war, my lord, is lost!

Freeview HD is.... (sorry, Ive run out of expletives) DOG ****E!


Yes, Camera 1 out of the scanner/studio is a different world to what
comes back off air. Always was, whatever the system.

FTR, I live right next to a major BT exchange.
There isnt even a cabinet between me and the exchange.
I get 13Mb/s!! (twisted pair phone line)


Your cable is faulty then. On one I monitor, it is currently syncing
at 19.4Mb/s and the line is almost exactly a mile long.
  #13  
Old August 3rd 15, 09:50 PM posted to uk.tech.digital-tv
_Unknown_Freelancer_
external usenet poster
 
Posts: 75
Default 4k TV on Freesat or Freeview?

"Paul Ratcliffe" wrote in message
...
On Mon, 3 Aug 2015 19:22:14 +0100, _Unknown_Freelancer_ /dev/null wrote:

The war, my lord, is lost!

Freeview HD is.... (sorry, Ive run out of expletives) DOG ****E!


Yes, Camera 1 out of the scanner/studio is a different world to what
comes back off air. Always was, whatever the system.



I know.
But the point I was making is that so called 'HD' is not what it says on the
tin, because RMC said "Freeview HD looks good" in the previous post.
Its barely SD.
Its VHS. S-VHS if you must.

The the digital revolution/HD upgrade was supposed to improve things.
Well, it shoud have, if the bean counters hadnt reigned in on the bit rates
the broadcasters use.
.....and this is because a private company (Arqiva) now run our terrestrial
networks.... who want pennies per bit.

I never expect the off air signal to be 'grade 1'.
But I do expect it to be far superior than what I recorded on magnetic tape
in 1995.
Instead we get YouTube 2005 quality.... a new kind of ****e.



FTR, I live right next to a major BT exchange.
There isnt even a cabinet between me and the exchange.
I get 13Mb/s!! (twisted pair phone line)


Your cable is faulty then. On one I monitor, it is currently syncing
at 19.4Mb/s and the line is almost exactly a mile long.


No, its not faulty.
Its been tested. No faults.
Its 20 years old. So will not be replaced.
Virgin do not have any equipment in the exchange. So no other 'strong
contenders'.
Both Virgin and BT will not lay fibre or co-ax in to my street. (Already
asked both)
So my neighbours and I are stuck with it.



  #14  
Old August 4th 15, 10:21 AM posted to uk.tech.digital-tv
Andy Furniss[_3_]
external usenet poster
 
Posts: 130
Default 4k TV on Freesat or Freeview?

_Unknown_Freelancer_ wrote:

The quality you see on HD Freeview equates to SD quality at source.
i.e. What you see on telly is only as good as broadcast quality SD
(at source) ever was.


I agree that the bitrates are too low, but on something like park-run
from below, a 10 mbit h264 is still looks better than a de-interlaced
scaled up raw 576i. I could try harder WRT deint/scale quality - but I
doubt that would really help. Maybe the source is not up to modern
standards? Those samples do seem to get a lot of "research" done on them
- but then I am just an idly/lazily half interested amateur.

Of course watching the raw 1080i25 is even nicer - but it still needs
de-interlacing and that + the shutter speed still means the grass/snow
in the foreground is blurred during the pan.

At least UHD will avoid the de-interlace and in the future 120fps help
with the shutter speed blur.

I bet 10mbit hevc would look better than the same rate 264 on parkrun -
but I would have to cheat as I don't think free lib/ffmpeg will code
interlaced yet. I know hevc just does fields anyway - maybe deint first
to 50p wouldn't be cheating too much, but it's currently so slow I could
never play it at full speed on my old PC.

ftp://vqeg.its.bldrdoc.gov/HDTV/

for raw video + details of.



  #15  
Old August 4th 15, 10:50 AM posted to uk.tech.digital-tv
Andy Furniss[_3_]
external usenet poster
 
Posts: 130
Default 4k TV on Freesat or Freeview?

Andy Furniss wrote:

ftp://vqeg.its.bldrdoc.gov/HDTV/

for raw video + details of.


To be more specific I am looking at the 576i25 and 1080i25 park run
(converted to 420) - though watching 422 makes no difference, it
wouldn't be a fair test as I had to convert to 420 to make a
representative h264 anyway.

ftp://vqeg.its.bldrdoc.gov/HDTV/SVT_...ekas_Exports_/


  #16  
Old August 4th 15, 07:42 PM posted to uk.tech.digital-tv
_Unknown_Freelancer_
external usenet poster
 
Posts: 75
Default 4k TV on Freesat or Freeview?

Sorry, was a wee bit busy earlier.


"Andy Furniss" [email protected] wrote in message
o.uk...
_Unknown_Freelancer_ wrote:

The quality you see on HD Freeview equates to SD quality at source.
i.e. What you see on telly is only as good as broadcast quality SD
(at source) ever was.


I agree that the bitrates are too low, but on something like park-run
from below, a 10 mbit h264 is still looks better than a de-interlaced
scaled up raw 576i. I could try harder WRT deint/scale quality - but I
doubt that would really help. Maybe the source is not up to modern
standards? Those samples do seem to get a lot of "research" done on them
- but then I am just an idly/lazily half interested amateur.



Why would you de-interlace 576i? At all?
If you want to intentionally make PAL look bad, you de-interlace it.

Although I notice certain 'arty types' in sports production actually add a
'film effect' to some items.
Aparently its 'art'.
.....with a capital F me thinks!


The key to its success was that it refreshed the screen (albeit at half
resolution) fifty times a second*.
The same 'higher refresh rate' rule applies today. It gives clarity in any
fast motion, such as sports.

*FWIW, the half resolution higher refresh rate was chosen at the time
because they couldnt get phosphor to glow long enough for a progressive scan
without producing flicker.

Source quality SD contains more detail than present DTT HD.

Please do not misunderstand this and interpret this as me saying SD HD.
Simply not the case.
Its once a picture has gone through the terretrial transmission chain.

A few years ago, someone at ITV49 had a great idea to make a 'reality'
programme interactive by placing a QR code in the top tight of the screen.
It worked perfectly in the edit. The website and chat rooms were all set up.
Then the programme went to air..... no-ones phone could interpret the QR
code.... because it had been compressed to a grey blur!

Some muppet just had not thought that one through, and its never been seen
since!

And this was something that wasnt even moving.
It was a permanent stationary graphic.
At no time was there sufficient capacity to send any definition detail. So
it stayed as a grey smudge.



Of course watching the raw 1080i25 is even nicer - but it still needs
de-interlacing and that + the shutter speed still means the grass/snow
in the foreground is blurred during the pan.



Again, why do you need to de-interlace ??
Wht are you intent on de-interlacing?
When SMPTE created these new standards they set added interlaced for
distinct reasons.
i.e. They didnt do it for a laugh, or while they were down the beer keller!

The shutter speed does not cause the grass to be 'blurred during the pan'.
There is 'motion blur', which is what occurs when the camera moves. Super
motion and HiMo cameras negate this because of their increased aquistion
frame rates, which is then played back at 50i.

And there is artificting blur, because the broadcaster has compressed the
source to VHS quality, and ALL the grass becomes one green smudge. Because
there is insufficient bandwidth to transmit a reasonable amount of detail.

There is a distinct difference between the two.




At least UHD will avoid the de-interlace and in the future 120fps help
with the shutter speed blur.


DO NOT be so sure that any forthcoming UHD channels will transmit, or even
originate, at 120fps.

I know, and full well understand that is the intention, the long term goal.
But at present, its just about getting 4K out before the other broadcasters
do.
Four thousand horizontal pixels in a progressive scan constitutes UHD.
120fps does not constitute, nor is a requirement of, UHD.

As with everything else, bits = pennies, hence not neccesarily leaping
straight to 120fps.




I bet 10mbit hevc would look better than the same rate 264 on parkrun -


No.
HEVC macro block size is eight times bigger than that of h.264. (64x64)
Yes there would be far less data, but there would also be far bigger square
artificts*. Eight times bigger.
*See also YouTube 2005.

but I would have to cheat as I don't think free lib/ffmpeg will code
interlaced yet.


Yes, it does.
http://x265.readthedocs.org/en/defau...-intra-options

CTRL+F 'interlace'


I know hevc just does fields anyway


According to the manual (above), it can do interlaced.
Crazy, I know, but it seems it will.

- maybe deint first


You are obsessed with progressive scan!!!

I know 'its better', and just like 'garlic bread', 'its the future'.
But if something is sourced in an interlaced standard, and the equipment you
play back on can handle interlaced images, why ruin it?

to 50p wouldn't be cheating too much,


And in encoding to 50p you double the required data rate.

but it's currently so slow I could
never play it at full speed on my old PC.

ftp://vqeg.its.bldrdoc.gov/HDTV/

for raw video + details of.


To be more specific I am looking at the 576i25 and 1080i25 park run
(converted to 420) - though watching 422 makes no difference, it
wouldn't be a fair test as I had to convert to 420 to make a
representative h264 anyway.

ftp://vqeg.its.bldrdoc.gov/HDTV/SVT_...ekas_Exports_/


Changing pixel format, or colour space, will make zero difference to
definition or detail contained within an image.
It relates to colour handling.
i.e. How you record the brightness of three neighbouring pixels.

Yes, some colour spaces are not compatible with some encoders.
But that was in mind when certain encoders were constructed.

Even reduced to 1:0:0 (monochrome), an image would still contain detail,
edge definition, and clarity.
e.g. A graphic consisting of words would still contain precise edge detail
in monochrome, in 1:0:0.
A moving shot of a pitch would still contain the detail and definition of
the playing surface.

Only once you push that through an inter-frame encoder, that is when you
loose detail.
That is when graphics suddenly get an aura of their own. (Derek Acorah not
included.)
By which I mean an extra unintended pixel shadow 1 to 3 pixels wide around
the whole edge of any graphics.


Going back to my original point, that if anyone transmitted _source quality_
SD now (using the same bandwidth which is applied to HD. i.e. uncompressed
SD), it would appear to contain more detail than the DTT dog faeces we get
presently.

Therefore, why, instead of nob waving, launching half cocked 4K, why doesnt
someone have the bright idea of transmitting 'better HD'??
"True HD" even??
It would save trucks full of money for all concerned for a start!



  #17  
Old August 4th 15, 10:38 PM posted to uk.tech.digital-tv
Dave W
external usenet poster
 
Posts: 287
Default 4k TV on Freesat or Freeview?

On Mon, 3 Aug 2015 19:22:14 +0100, "_Unknown_Freelancer_" /dev/null
wrote: (amongst other things)

Any captions or graphics, any channel. They should all have distinct sharp
edges.
Look again, and you'll see a border around everything, about 1 to 3 pixels
wide.
....because the transmitted mpg stream doesnt have enough bandwidth to
detail the edges of graphics.

"HD" is not HD.
Yes, its 'High', lots of pixels and vertical lines, but no 'Definition'.

The quality you see on HD Freeview equates to SD quality at source.
i.e. What you see on telly is only as good as broadcast quality SD (at
source) ever was.

Thus, the 'digital tv' rip off.
Freeview HD does not look good.


My TV, fed from HD Freesat, has to have "sharpness" turned to zero to
get rid of the horrible borders and exaggerated detail. The HD looks
good to me. In fact too good, exposing the make-up applied to female
presenters to make them look good in SD.
--
Dave W

  #18  
Old August 4th 15, 11:48 PM posted to uk.tech.digital-tv
Andy Furniss[_3_]
external usenet poster
 
Posts: 130
Default 4k TV on Freesat or Freeview?

_Unknown_Freelancer_ wrote:
Sorry, was a wee bit busy earlier.


"Andy Furniss" [email protected] wrote in message
o.uk...
_Unknown_Freelancer_ wrote:

The quality you see on HD Freeview equates to SD quality at
source. i.e. What you see on telly is only as good as broadcast
quality SD (at source) ever was.


I agree that the bitrates are too low, but on something like
park-run from below, a 10 mbit h264 is still looks better than a
de-interlaced scaled up raw 576i. I could try harder WRT
deint/scale quality - but I doubt that would really help. Maybe
the source is not up to modern standards? Those samples do seem to
get a lot of "research" done on them - but then I am just an
idly/lazily half interested amateur.



Why would you de-interlace 576i? At all? If you want to
intentionally make PAL look bad, you de-interlace it.


It's 2015 - I don't have an interlaced display any more!

De-interlace and scale is what my (and I guess most peoples) TV does to
25i I could let it do it or I can do it in s/w my self.

Although I notice certain 'arty types' in sports production actually
add a 'film effect' to some items. Aparently its 'art'. ....with a
capital F me thinks!


Not filmic that would imply deint to 25p (eww) TV/me would of course do 50p.

The key to its success was that it refreshed the screen (albeit at
half resolution) fifty times a second*. The same 'higher refresh
rate' rule applies today. It gives clarity in any fast motion, such
as sports.

*FWIW, the half resolution higher refresh rate was chosen at the time
because they couldnt get phosphor to glow long enough for a
progressive scan without producing flicker.

Source quality SD contains more detail than present DTT HD.


The part run samples I pointed to are source quality aren't they?

Whatever I try I can't get the raw 576i to look as good as a 10mbit
encode of the 1080i.

Different cameras of course (same lens), detail -

ftp://vqeg.its.bldrdoc.gov/HDTV/SVT_exports/README.txt


Please do not misunderstand this and interpret this as me saying SD
HD. Simply not the case. Its once a picture has gone through the

terretrial transmission chain.


I don't see why my 10mbit x264 encode should beat pro kit - assuming of
course they would give that much bitrate to similar content.

A few years ago, someone at ITV49 had a great idea to make a
'reality' programme interactive by placing a QR code in the top
tight of the screen. It worked perfectly in the edit. The website and
chat rooms were all set up. Then the programme went to air.....
no-ones phone could interpret the QR code.... because it had been
compressed to a grey blur!

Some muppet just had not thought that one through, and its never
been seen since!

And this was something that wasnt even moving. It was a permanent
stationary graphic. At no time was there sufficient capacity to send
any definition detail. So it stayed as a grey smudge.


That is amusing, and I don't doubt that DTT bitrates are terrible. Back
when I had both analogue and DTT on a CRT it was plain to see people had
hairy arms etc. that disappeared on the mpeg2 version. Of course that
was SD - SD. I am still unconvinced that 702x576 even raw will beat HD
even if it is somewhat bitrate crippled.

Of course watching the raw 1080i25 is even nicer - but it still
needs de-interlacing and that + the shutter speed still means the
grass/snow in the foreground is blurred during the pan.



Again, why do you need to de-interlace ?? Wht are you intent on
de-interlacing? When SMPTE created these new standards they set
added interlaced for distinct reasons. i.e. They didnt do it for a
laugh, or while they were down the beer keller!


Reluctantly to halve the bandwidth while giving decent temporal res.

Do you pros still use interlaced displays then? At work/at home/for HD?

I mean surely most people now see interlaced on a progressive display =
it's de-interlaced. If I put my Panny plasma into an interlaced mode it
de-interlaces (motion adaptively). It doesn't become an interlaced
display. I can de-interlace in s/w to achieve the same effect on a
dumber display (my 1920x1080 computer monitor).

The shutter speed does not cause the grass to be 'blurred during the
pan'. There is 'motion blur', which is what occurs when the camera
moves. Super motion and HiMo cameras negate this because of their
increased aquistion frame rates, which is then played back at 50i.


OK - you are in the trade, but I do recall shutter speed getting a
mention in one of the BBC R&D high framerate papers.

And there is artificting blur, because the broadcaster has
compressed the source to VHS quality, and ALL the grass becomes one
green smudge. Because there is insufficient bandwidth to transmit a
reasonable amount of detail.

There is a distinct difference between the two.


Fair enough, though the blur on the raw 1080i25 park run is clearly not
the latter, though total mush it isn't.

At least UHD will avoid the de-interlace and in the future 120fps
help with the shutter speed blur.


DO NOT be so sure that any forthcoming UHD channels will transmit,
or even originate, at 120fps.

I know, and full well understand that is the intention, the long
term goal. But at present, its just about getting 4K out before the
other broadcasters do. Four thousand horizontal pixels in a
progressive scan constitutes UHD. 120fps does not constitute, nor is
a requirement of, UHD.

As with everything else, bits = pennies, hence not neccesarily
leaping straight to 120fps.


Yes, I'm not upgrading till it's the norm (if I live that long) :-)

I bet 10mbit hevc would look better than the same rate 264 on
parkrun -


No. HEVC macro block size is eight times bigger than that of h.264.
(64x64) Yes there would be far less data, but there would also be
far bigger square artificts*. Eight times bigger. *See also YouTube
2005.

but I would have to cheat as I don't think free lib/ffmpeg will
code interlaced yet.


Yes, it does.
http://x265.readthedocs.org/en/defau...-intra-options



CTRL+F 'interlace'


OK, I'll have to revisit that. I do recall there being an issue
somewhere, so I guess it is/was ffmpeg - possibly that it can't/couldn't
actually play interlaced properly as it is/was used to getting weaved
frames from decoders, not fields.

I know hevc just does fields anyway


According to the manual (above), it can do interlaced. Crazy, I
know, but it seems it will.


What I meant buy fields was it doesn't (AFAIK) do anything complicated
for interlaced like mpeg2/h264 did - like they really wanted not do
interlaced, but did simply = coding fields and nothing more.

- maybe deint first


You are obsessed with progressive scan!!!

I know 'its better', and just like 'garlic bread', 'its the future'.
But if something is sourced in an interlaced standard, and the
equipment you play back on can handle interlaced images, why ruin
it?


My TV de-interlaces, I can do the same (possibly better) to play back on
a monitor that doesn't.

to 50p wouldn't be cheating too much,


And in encoding to 50p you double the required data rate.


True - but then weaved frames are also "extra" complicated so I don't
think it would need 2x bits for the sameq. It would be a different test
though.


but it's currently so slow I could never play it at full speed on
my old PC.

ftp://vqeg.its.bldrdoc.gov/HDTV/

for raw video + details of.


To be more specific I am looking at the 576i25 and 1080i25 park run
(converted to 420) - though watching 422 makes no difference, it
wouldn't be a fair test as I had to convert to 420 to make a
representative h264 anyway.

ftp://vqeg.its.bldrdoc.gov/HDTV/SVT_...ekas_Exports_/


Changing pixel format, or colour space, will make zero difference to
definition or detail contained within an image. It relates to
colour handling. i.e. How you record the brightness of three
neighbouring pixels.

Yes, some colour spaces are not compatible with some encoders. But
that was in mind when certain encoders were constructed.

Even reduced to 1:0:0 (monochrome), an image would still contain
detail, edge definition, and clarity. e.g. A graphic consisting of
words would still contain precise edge detail in monochrome, in
1:0:0. A moving shot of a pitch would still contain the detail and
definition of the playing surface.

Only once you push that through an inter-frame encoder, that is when
you loose detail. That is when graphics suddenly get an aura of
their own. (Derek Acorah not included.) By which I mean an extra
unintended pixel shadow 1 to 3 pixels wide around the whole edge of
any graphics.


Going back to my original point, that if anyone transmitted _source
quality_ SD now (using the same bandwidth which is applied to HD.
i.e. uncompressed SD), it would appear to contain more detail than
the DTT dog faeces we get presently.

Therefore, why, instead of nob waving, launching half cocked 4K, why
doesnt someone have the bright idea of transmitting 'better HD'??
"True HD" even?? It would save trucks full of money for all
concerned for a start!


Better HD yes - I am still not convinced it's quite as bad as SD, though
- maybe I don't watch enough TV (usually motorsport) - perhaps park run
is misleading (I obviously don't have access to much else to compare),
but to me 10mbit x264 HD wins over raw SD for that.
  #19  
Old August 5th 15, 04:22 PM posted to uk.tech.digital-tv
R. Mark Clayton[_2_]
external usenet poster
 
Posts: 649
Default 4k TV on Freesat or Freeview?

On Monday, 3 August 2015 19:22:22 UTC+1, _Unknown_Freelancer_ wrote:
"R. Mark Clayton" wrote in message
...
On Monday, 3 August 2015 12:07:38 UTC+1, _Unknown_Freelancer_ wrote:
"Michael Chare" wrote in message
...
4K TVs are becoming available and more reasonable prices and there are
some 4k internet streaming channels.

So when, if ever, will any of the Freesat or Freeview channels convert
to
4K?

--
Michael Chare


4K ....over Freeview?
One hopes you are 'having a laugh'. Seriously.

Consider that this stuff originates at 12Gb/s.
Tweleve gigabits of data, per second.
In comparison, present HD originates at just under 1.5Gb/s.

And to compress this enough so that its transmittable over freeview, you
would have to dispense with so much information that you would render
'UHD'
pointless.
i.e. The loss in quality would be so bad that it would be comparable to
existing HD. Therefore, just what is the point?

The only way to transmit 'acceptable' UHD is either usings serveral
channel
spaces over satellite, or proper* broadband.
* meaning something better than BTs standard twisted pair phone line.
Either
the co-ax that Virgin is installing, or fibre from both BT and Virgin.

4K over Freeview?
Hopefully, never.


UHD is certainly no more than four times the bandwidth of 1080i, which is
broadcast in the teens of Mbps (SD usually less than half that).

With more sophisticated compression BT expect to be able to get UHD down a
30-40Mbps pipe, which curiously enough is what you normally get from FTTC.
This will also fit onto a single satellite transponder. These currently
carry up to ten SD channels or two to three HD ones.

Different argument for Freeview, although Freeview HD looks good.







"Freeview HD looks good."

"...looks good" ????



The war, my lord, is lost!

Freeview HD is.... (sorry, Ive run out of expletives) DOG ****E!

Next time there's a field based sport on telly, watch it.
Instead of watching 'the action', watch the detail in the grass when the
camera moves around.

The grass turns to one big green VHS* quality mush. All the detail in the
grass disappears.
When I say VHS quality, I mean the tape you left in the deck for that
'emergency crash in to record' occasion!

The detail only returns to the grass when the camera stops moving.
....once the mpg encoding has enough bandwidth to restore picture detail.


As it happens we only bought a [small] Freeview HD TV (for the kitchen) relatively recently. The picture on the HD channels is noticeably better than SD.

Our main TV is Freesat and the smearing etc. that you mention does not occur very much on that, however BT TV (over the internet) of a football match suffered in exactly the way you describe.



Next, take any 'shiney floor show' on ITV.... well, just about any programme
on ITV which isnt a vacuous soap or period drama.
Wait for the confetti drop at the end of the programme.... And just like
Cillit Bang, the detail is gone!
....too many different items moving in too many different directions for mpg
encoding to be able to maintain any reasonable level of detail, resulting in
a picture resembling a YouTube video in 2005!

Any captions or graphics, any channel. They should all have distinct sharp
edges.
Look again, and you'll see a border around everything, about 1 to 3 pixels
wide.
....because the transmitted mpg stream doesnt have enough bandwidth to
detail the edges of graphics.

"HD" is not HD.
Yes, its 'High', lots of pixels and vertical lines, but no 'Definition'.

The quality you see on HD Freeview equates to SD quality at source.
i.e. What you see on telly is only as good as broadcast quality SD (at
source) ever was.

Thus, the 'digital tv' rip off.
Freeview HD does not look good.




FWIW, UHD IS more than four times the bandwidth.


No it is four times the resolution.


A 4K video source produces four 3Gb/s streams.
.....that was the method SMPTE came up with.

A 4K camera has four video outputs BNCs. Each containing a 3Gb/s stream.
4 x 3 = 12Gb/s

As opposed to a 1080 HD camera, which produces one 1.5Gb/s stream from one
BNC socket.

And you want to compress 12Gb/s down to teens of Mb/s ????
Just what do you think will happen to your detail? ....to your picture
definition?
You think it will be 'Ultra High' do you?


Well I am sitting in front of a 4k monitor running at 60Hz. The signal comes down one DisplayPort cable and IIRC it can manage 4k @ 30Hz on HDMI.



"....better compression....blah"
Its called HEVC, or h.265.
....Which is also ********!

All they did was take h.264 and make the macro blocks bigger, and tweak
colour spacing.
i.e. the size of the squares the encoder carves the picture in to.

So when you get a 4K ITV shiney floor show (HA HA HA HAAAAAAAA! Shortly
after hell freezes over), the size of the squares the confetti drop causes
will be four times bigger.
i.e. it will still be dog ****e!


On the plus side, the UHD pictures you see will by that point be source HD
quality at least!
i.e. You will see at home what we presently see at source in HD.


At present, if a football match is shot in 4K, it is possible to make out
the detail in peoples faces _in the opposite stand_.
It is actually possible to lip read whilst the camera is sat on a wide shot,
such is the level of detail in 4K.
If you compress it..... well, whats the point?



FTR, I live right next to a major BT exchange.
There isnt even a cabinet between me and the exchange.
I get 13Mb/s!! (twisted pair phone line)


That is because dozy BT would put the ADSL2 connection on direct to exchange lines (now sorted I believe).

As I said previously, to get decent bandwidth to the home requires either
fibre or co-ax.


Which BT installed where I am in 2009 (OK the first in the UK), giving you a maximum of 76Mbps. Cable also passes most homes (not ours - it is on a private road) and will give you 100Mbps. I ordered the 38Mbps option, and allowing a little loss for protocol overheads, that's what I get.

.....not a lot of that about, and in some areas, just aint gonna happen.


Same with buses - if you choose to live in Hicksville, Montana you ain't going to get a two minute service.
  #20  
Old August 5th 15, 08:02 PM posted to uk.tech.digital-tv
Andy Furniss[_3_]
external usenet poster
 
Posts: 130
Default 4k TV on Freesat or Freeview?

R. Mark Clayton wrote:

FWIW, UHD IS more than four times the bandwidth.


No it is four times the resolution.


Yes, but the source bitrate is 8x as you have to account for current HD
only being 25 fps or 50 fields per sec. UHD doesn't use interlacing so
50fps doubles the source bandwidth on top of the res increase. This
means for sport that the vertical res increase is (more than?) 4 times
HD. The "more than" may be debatable - but I think interlaced gets extra
filtering to prevent interline twitter.

 




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