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4k TV on Freesat or Freeview?



 
 
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  #41  
Old August 9th 15, 02:40 PM posted to uk.tech.digital-tv
_Unknown_Freelancer_
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Posts: 75
Default 4k TV on Freesat or Freeview?

"Paul Ratcliffe" wrote in message
...
On Thu, 6 Aug 2015 13:25:21 +0100, UnsteadyKen

wrote:

I know that, I have come across controls before, and it was you who
started blathering about numbered sliders and all that guff in a
desperate attempt to cover your arse when it was pointed out you were
talking bollox, IE, turning sharpness processing off does not reduce
the resolution and make the picture go all blurry,as you claimed.


It certainly did on the old tube cameras. Turning contours off made
the picture as soggy as anything and essentially unusable. I think we
used to do that during registration line-up, but it has been rather a
long time since then...


a.k.a. 'Edge' ....was also labelled same on CCUs and OCPs.


Ads
  #42  
Old August 9th 15, 02:55 PM posted to uk.tech.digital-tv
_Unknown_Freelancer_
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Posts: 75
Default 4k TV on Freesat or Freeview?

"R. Mark Clayton" wrote in message
...
On Wednesday, 5 August 2015 21:02:39 UTC+1, Andy Furniss wrote:
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.


You are still thinking about building a rasterised image with the picture
built up in [alternate] lines every [other] frame time.

More recent methods send the full frame every so often and the changes
every frame time. This works great for static images or for video where
things in the view change, but can generate artefacts when the camera pans
or zooms.


"....full frame every so often" = i frame, start of a GOP, Group Of Pictures
e.g. a video stream may have a GOP of 75 frames

Point is though, yes, (at source) 4K is four times the resolution of HD, but
it produces eight times the data of HD.


  #43  
Old August 9th 15, 03:06 PM posted to uk.tech.digital-tv
_Unknown_Freelancer_
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Posts: 75
Default 4k TV on Freesat or Freeview?

"R. Mark Clayton" wrote in message
...
On Wednesday, 5 August 2015 21:09:05 UTC+1, _Unknown_Freelancer_ wrote:
"Andy Furniss" [email protected] wrote in message
o.uk...
SNIP


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.


How do you know this?
Do you have the source code from the manufacturer?

You don't need it.

For a CRT interlacing relies on the persistence of the phosphor, so
alternate lines are drawn every frame (50fps (576i)in EU, 60fps in US).
The primary reason for doing this is to reduce the flicker that that would
be very obvious if the whole frame were drawn every time (so 25fps in the
EU).

Later CRT TV's would remember the contents of every line and redraw the
whole screen every frame time (and SECAM sets may have had this feature
longer). CRT monitors topped out at [email protected] around the mid

noughties.

More recent flat screen panels rely on a different method. Basically a
pixel will stay in a particular state until it is told to do something
different.

My 4k panel here was restricted to [email protected] until AMD got around to fixing
their drivers. This would affect high speed motion, but not downloaded
video nor static images.




UHD will be an even bigger rip off, with even more detail lost!


bigger rip off than what? Already the premium for 4k over full HD is quite
modest and no detail will be lost. It is plausible that you won't get all
4k of the detail due to compression etc., but you certainly won't get
less.



A bigger rip off than DTT HD.
.....which is the whole reason this thread exploded the way it did.
Ground zero was my venting steam on 3rd August in reply to MC anticipating
4K over freeview.

Freeview HD is poop.
Therefore 'Freeview 4K' makes people in TV laugh.
It will be an even bigger rip off than Freeview HD.

And note the distinct use of the word 'Freeview'.
Freesat, Sky, Virgin, and BT methods of distribution offer more bandwidth,
and therefore will not be anywhere as bad.


  #44  
Old August 9th 15, 03:40 PM posted to uk.tech.digital-tv
_Unknown_Freelancer_
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Posts: 75
Default 4k TV on Freesat or Freeview?

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


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.


How do you know this? Do you have the source code from the
manufacturer?


No, but that doesn't mean they don't.

There must be many chips sold for the purpose (I know they also do more
complicated processing as well)

I do know that my TV de-interlaces as I can test it with a computer.

Manufacturers spend a lot of time and effort over their kit before
they put it to market. Ok, so there is the occasional lemon model,
but on the whole, most kit does what it says on the tin.

Just because an OLED screen only came out of the factory in January
2015, does not mean it can not interpret an interlaced scan 'is as.
Without the source code, for all we know (when watching 1080i) it may
well actually only update all the odd lines in one pass, and then all
the even in the next.


Should be easy enough to take a pic to prove/disprove. Many TV reviews
seem to test "the deinterlacer" so I assume many TVs don't work by
simulating a CRT.

In which case, leaving source interlaced stuff as interlaced IS the
best thing to do.

Let the equipment decide what to do with it.


Oh I can and do let my TV do its thing - observing the quality of its
de-interlacing and scaling also lets me say that I can equal/beat it
with my own processing. It's not top end TV, but not budget either, it
got good reviews.

As previously, SMPTE didnt make up their standards for fun. And Im
pretty sure the manufacturers didnt toss a coin when writing the
code to decide how it should handle different display modes.

And in 'scaling' you're again compromising your own pictures. Once
you scale, you've ruined your copy for good.


Well someone/something has got to scaled to get SD on an HD panel.

Who said anything about changing master copy - I can choose different
scale eg.lanczos at display time thanks to open source geeks and OpenGL.

I could also use ffmpeg, I can deinterlace on the fly, but I think a
motion compensated de-int that runs at 0.1 fps will beat it. I have
choice to do whatever I want


ffmpeg is good stuff. Although this may not be good news:
http://www.theregister.co.uk/2015/08...er_steps_down/


i.e. You resample all the colour spacing, you contrive any
representation.

Again, leave it as you got it, let the screen decide what to do with
it.


Or do better....


Ok, fair enough.

Just seems like a lot of faff tbh!

Leap forward fifteen years. Screens will still have backward
compatitibility, and will be capable of rediculous resolutions....
but at that point in time the manufacturers will have better means of
making older formats work well on their screens.


True, and some of the methods they will do realtime are likely already
proposed in existing papers, peoples masters/PHDs. Just they currently
are far too slow.

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.


No. Because it still leaves Tx at 50i. You're not going to change the
whole transmission chain for one vt package, are you?


It was you that mentioned filmic, which I assumed meant 25p - I can't
recall suggesting changing Tx!

FWIW on FreeviewHD 25p is flagged as progressive.


Well, it appeared that after I wrote that sports types apply a film effect,
you got the idea they deinterlaced it.
But you cant do that. You cant deinterlace a picture which is operating in
an interlaced environment.
Well you can, but then it all goes to cock!
Which is why I wrote what I did.

Really, all the kit does is send field 1 to field 1 AND 2 = _cheap_ film
effect




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


TL;DR! But, I dont think thats relevant anyway. Im comparing source
SD to DTT 'HD'. Lab test vs Real world.


Well I've got sport recordings that are 10mbit and so it's not like they
never go that high. I must admit that Park Run at 5mbit is horrible, but
at 10 it's OK.


Dunno, ISTR Sky Sports F1 is 15Mb/s.... or something approaching that.
.....only so that their pictures were better than BBC1s when they penned the
present deal.


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


But without the source HD material, how do you know what
detail/definition has been lost to compare?


I do have the HD source - that's what the 10mbit 264 was made from!

Comparing HD to HD wasn't the point, of course 10mbit is not as good as
the raw - but it's way better than the raw SD.

Generally compression occurs by smoothing edges (loosing detail), and
then finding repeat patterns in a frame (which buggers up captions).


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.



Because its compressed to ****e by Arqiva! Because the broadcasters
dont want to pay any more s!


I thought the BBC coded the main HD mux and Aquiva did com 7/8.


AFAIK its Arqiva.

Was it late last year there was the mass renumbering of channels?
Cant remember?
They told the public it was to improve service and make more space.
********!

It was because Arqiva went out and purchased a whole truck load of new mux
boxes!

In the following months kit auction sites were flooded with 'pre-owned'
MPEG2 muxers!
.....all ex-Arqiva!



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.


But you wont be halving the data rate.


I meant that the reason interlaced still survives and gets standards
despite eg, the EBU trying to get rid for HD is because it's half the
data rate compared to 50p.

https://www.ebu.ch/en/technical/trev...editorial.html

I know its the other end of the spectrum, but the maths is still the
same: (or "math", if youre "murican") 1080i50 (1080 interlaced, 25
fps, alternate lines refreshed at 50fps) = 1.5Gb/s (because you are
sending 1080/2= 540 lines 50 times a second) 1080p50 (1080
progressive lines, refreshed at 50fps) = 3Gb/s (because you are
sending all 1080 lines every 50 times a second)


I can do sums.

So, unless you're converting 1080i50 (off air telly) to 1080p25, you
are doubling your data rate by converting to 1080p50


I am fully aware of that.
.
.....and ruining the source by deinterlacing it needlessly.


Or doing as good as/better than the realtime deint my TV does.

And it's precisely the same if you're doing this with SD off air.
Converting 576i to 576p doubles your data rate.


I know that - just trying to get raw SD at its best to compare with
10mbit HD for comparison - not as a general policy for viewing - as I
said I let my TV deint that.


BUT.... you may well notice the occasional f.cup with 'regional
news'. ENG have gone out and shot something, usually out of focus,
and recorded with more audio distorion than a Foo Fighters concert!
Content goes back to the edit, and the clown at the keyboard, who has
a non-linear (computer) edit in front of him, hasnt bothered to check
it on a proper telly. i.e. They've only watched it on their computer
screen. When it goes to air any horizontal motion shivvers....
because they've got the field dominance the wrong way round!


Well they should really have just done a quich check with yadif=1 :-)


_SHOULD_.
But just like some ENG 'camera' ops dont bother to check an image is focused
before pressing record, some 'editors' dont bother to check on a proper
telly before pressing 'Export'.


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).


As per first point above, without manufacturers source code, how do
you know that just because your telly only fell of Dixons shelf
yesterday, that it still doesnt update the display in an interlaced
fashion?


Answered above for me, but it's unlikely even if there are TVs that
simulate CRTs they would do it for 576i on an HD panel.


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

True - but then weaved frames are also "extra" complicated so I
don't


No, they're not. Its just half the lines, with a flag.


I think in practice mpeg2 and h264 encoders do full weaved frames rather
than fields - but anyway it was just me thinking out loud about how to
compare x265 with x264.

It seems currently ffmpeg doesn't re-weave the output of its hevc
decoder. x265 also warns that interlace support is experimental if you
try to use it.


.....could be the case that its 'experimental' because only ffmpeg have
included it as an option.
i.e. No-one else pushing the 4K envelope may not be bothering.

As Ive written previously, all ffmpeg does is include a flag in alternate
frame data.



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.



A 'lab test' is not as good as a 'real world' test. Our real world
test is FTA Freeview HD. Compared to source HD, you're all being
ripped off severely!


Well yes, but I am comparing for the claim that it's worse than raw SD
so if anybody ever broadcasts park run I will record it and see real
world rather than my "lab" :-)

UHD will be an even bigger rip off, with even more detail lost!


Still no update on BTW wholesale connect sin WRT BT UHD.

Given that their HD offerings were 7.5mbit 1440 or "premium" 1920 at
10mbit it will be interesting to see what their UHD is.



  #45  
Old August 9th 15, 04:16 PM posted to uk.tech.digital-tv
R. Mark Clayton[_2_]
external usenet poster
 
Posts: 649
Default 4k TV on Freesat or Freeview?

On Sunday, 9 August 2015 15:06:10 UTC+1, _Unknown_Freelancer_ wrote:
"R. Mark Clayton" wrote in message


SNIP

UHD will be an even bigger rip off, with even more detail lost!


bigger rip off than what? Already the premium for 4k over full HD

TV
is quite
modest and no detail will be lost. It is plausible that you won't get all
4k of the detail due to compression etc., but you certainly won't get
less.



A bigger rip off than DTT HD.
....which is the whole reason this thread exploded the way it did.
Ground zero was my venting steam on 3rd August in reply to MC anticipating
4K over freeview.

Freeview HD is poop.
Therefore 'Freeview 4K' makes people in TV laugh.
It will be an even bigger rip off than Freeview HD.

And note the distinct use of the word 'Freeview'.
Freesat, Sky, Virgin, and BT methods of distribution offer more bandwidth,
and therefore will not be anywhere as bad.


The OP said Freesat or Freeview.

No sure how something that is and remains free can be a rip off?
  #46  
Old August 9th 15, 04:27 PM posted to uk.tech.digital-tv
_Unknown_Freelancer_
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Posts: 75
Default 4k TV on Freesat or Freeview?

"R. Mark Clayton" wrote in message
...
On Sunday, 9 August 2015 15:06:10 UTC+1, _Unknown_Freelancer_ wrote:
"R. Mark Clayton" wrote in message


SNIP

UHD will be an even bigger rip off, with even more detail lost!

bigger rip off than what? Already the premium for 4k over full HD

TV
is quite
modest and no detail will be lost. It is plausible that you won't get
all
4k of the detail due to compression etc., but you certainly won't get
less.



A bigger rip off than DTT HD.
....which is the whole reason this thread exploded the way it did.
Ground zero was my venting steam on 3rd August in reply to MC
anticipating
4K over freeview.

Freeview HD is poop.
Therefore 'Freeview 4K' makes people in TV laugh.
It will be an even bigger rip off than Freeview HD.

And note the distinct use of the word 'Freeview'.
Freesat, Sky, Virgin, and BT methods of distribution offer more
bandwidth,
and therefore will not be anywhere as bad.


The OP said Freesat or Freeview.

No sure how something that is and remains free can be a rip off?


Licence fee = not free

+Because its sold by the broadcasters as 'better/amazming/fantastic/pin
sharp/other generic superlative'.
.....when its not.
Thus, it is a lie, a rip off.


Watched Sunday Brunch on Freeview HD earlier. (Yes, I know, ironic! eyes
roll It was sunday morning and my head was fried! )
During 'settee' interviews was annoyed by the false halo added to
interviewees caused by the brightly coloured wall behind them.
......'transmission chain artifacts'.


  #47  
Old August 9th 15, 07:30 PM posted to uk.tech.digital-tv
R. Mark Clayton[_2_]
external usenet poster
 
Posts: 649
Default 4k TV on Freesat or Freeview?

On Sunday, 9 August 2015 16:35:24 UTC+1, _Unknown_Freelancer_ wrote:
"R. Mark Clayton" wrote in message
...
On Sunday, 9 August 2015 15:06:10 UTC+1, _Unknown_Freelancer_ wrote:
"R. Mark Clayton" wrote in message


SNIP

UHD will be an even bigger rip off, with even more detail lost!

bigger rip off than what? Already the premium for 4k over full HD

TV
is quite
modest and no detail will be lost. It is plausible that you won't get
all
4k of the detail due to compression etc., but you certainly won't get
less.


A bigger rip off than DTT HD.
....which is the whole reason this thread exploded the way it did.
Ground zero was my venting steam on 3rd August in reply to MC
anticipating
4K over freeview.

Freeview HD is poop.
Therefore 'Freeview 4K' makes people in TV laugh.
It will be an even bigger rip off than Freeview HD.

And note the distinct use of the word 'Freeview'.
Freesat, Sky, Virgin, and BT methods of distribution offer more
bandwidth,
and therefore will not be anywhere as bad.


The OP said Freesat or Freeview.

No sure how something that is and remains free can be a rip off?


Licence fee = not free


Unless you are watching in black and white no marginal cost at all.


+Because its sold by the broadcasters as 'better/amazming/fantastic/pin
sharp/other generic superlative'.


4k is - I am looking at it.

....when its not.


Freeview HD at 4K might not be.

Freesat at 4k might be as long as they give a whole transponder to each channel.

Thus, it is a lie, a rip off.


Watched Sunday Brunch on Freeview HD earlier. (Yes, I know, ironic! eyes
roll It was sunday morning and my head was fried! )
During 'settee' interviews was annoyed by the false halo added to
interviewees caused by the brightly coloured wall behind them.
.....'transmission chain artifacts'.


You sure your TV is set up right?

  #48  
Old August 9th 15, 07:40 PM posted to uk.tech.digital-tv
_Unknown_Freelancer_
external usenet poster
 
Posts: 75
Default 4k TV on Freesat or Freeview?

"R. Mark Clayton" wrote in message
...
On Sunday, 9 August 2015 16:35:24 UTC+1, _Unknown_Freelancer_ wrote:
"R. Mark Clayton" wrote in message
...
On Sunday, 9 August 2015 15:06:10 UTC+1, _Unknown_Freelancer_ wrote:
"R. Mark Clayton" wrote in message

SNIP

UHD will be an even bigger rip off, with even more detail lost!

bigger rip off than what? Already the premium for 4k over full HD
TV
is quite
modest and no detail will be lost. It is plausible that you won't
get
all
4k of the detail due to compression etc., but you certainly won't
get
less.


A bigger rip off than DTT HD.
....which is the whole reason this thread exploded the way it did.
Ground zero was my venting steam on 3rd August in reply to MC
anticipating
4K over freeview.

Freeview HD is poop.
Therefore 'Freeview 4K' makes people in TV laugh.
It will be an even bigger rip off than Freeview HD.

And note the distinct use of the word 'Freeview'.
Freesat, Sky, Virgin, and BT methods of distribution offer more
bandwidth,
and therefore will not be anywhere as bad.

The OP said Freesat or Freeview.

No sure how something that is and remains free can be a rip off?


Licence fee = not free


Unless you are watching in black and white no marginal cost at all.


....and in narrowscreen too??!!



+Because its sold by the broadcasters as 'better/amazming/fantastic/pin
sharp/other generic superlative'.


4k is - I am looking at it.


There's a 4K station on air now?



....when its not.


Freeview HD at 4K might not be.

Freesat at 4k might be as long as they give a whole transponder to each
channel.

Thus, it is a lie, a rip off.


Watched Sunday Brunch on Freeview HD earlier. (Yes, I know, ironic! eyes
roll It was sunday morning and my head was fried! )
During 'settee' interviews was annoyed by the false halo added to
interviewees caused by the brightly coloured wall behind them.
.....'transmission chain artifacts'.


You sure your TV is set up right?


Yes.



  #49  
Old August 9th 15, 08:38 PM posted to uk.tech.digital-tv
Paul Ratcliffe
external usenet poster
 
Posts: 2,486
Default 4k TV on Freesat or Freeview?

On Sun, 9 Aug 2015 11:30:23 -0700 (PDT), R. Mark Clayton
wrote:

Watched Sunday Brunch on Freeview HD earlier. (Yes, I know, ironic! eyes
roll It was sunday morning and my head was fried! )
During 'settee' interviews was annoyed by the false halo added to
interviewees caused by the brightly coloured wall behind them.
.....'transmission chain artifacts'.


You sure your TV is set up right?


Are you REALLY that clueless?
  #50  
Old August 9th 15, 08:53 PM posted to uk.tech.digital-tv
Vir Campestris
external usenet poster
 
Posts: 439
Default 4k TV on Freesat or Freeview?

On 09/08/2015 12:28, R. Mark Clayton wrote:
More recent methods send the full frame every so often and the changes every frame time. This works great for static images or for video where things in the view change, but can generate artefacts when the camera pans or zooms.


cough motion compensation

That's a bit of a simplification isn't it?

Andy
 




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