HD post-switchover
 

There's an interesting Ofcom document about it he

http://www.ofcom.org.uk/radiocomms/d.../hdmasters.pdf

Sorry if it's been posted before.


--
Steve - www.digitalradiotech.co.uk - Digital Radio News & Info

HD post-switchover
 

DAB sounds worse than FM wrote:
There's an interesting Ofcom document about it he

http://www.ofcom.org.uk/radiocomms/d.../hdmasters.pdf


Pages 15-16 say about 40 Mbps of extra capacity can be used to allow 5 HD
channels using 720p on a dedicated DVB-T2 mux, and to allow this the bit
rates of existing SD channels would have to be squeezed to the tune of 8.7
Mbps in total.

Hmmmmm. So they want to use 720p, which is medium-definition, IMO, not
high-definition, and they need to squeeze the bit rates significantly, which
are already squeezed too much as it is.

It's a good job I'm planning to get satellite before 2012!! And I sympathise
with everybody not getting it! And they'd better not use 720p on
satellite!!!!



--
Steve - www.digitalradiotech.co.uk - Digital Radio News & Info

HD post-switchover
 

On Thu, 04 Oct 2007 18:53:31 GMT, "DAB sounds worse than FM"
[email protected] wrote:

Hmmmmm. So they want to use 720p, which is medium-definition, IMO, not
high-definition, and they need to squeeze the bit rates significantly, which
are already squeezed too much as it is.

720p fits in with HD Ready TV's and probably 99% of HD TV's out there,
and is vastly superior to SD. It would be fine by me.
--
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Help make Usenet a better place: English is read downwards,
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HD post-switchover
 

Andrew wrote:
On Thu, 04 Oct 2007 18:53:31 GMT, "DAB sounds worse than FM"
[email protected] wrote:

Hmmmmm. So they want to use 720p, which is medium-definition, IMO,
not high-definition, and they need to squeeze the bit rates
significantly, which are already squeezed too much as it is.

720p fits in with HD Ready TV's and probably 99% of HD TV's out there,
and is vastly superior to SD. It would be fine by me.


Good for you.


--
Steve - www.digitalradiotech.co.uk - Digital Radio News & Info

HD post-switchover
 

"DAB sounds worse than FM" [email protected] wrote in message
...
DAB sounds worse than FM wrote:
There's an interesting Ofcom document about it he

http://www.ofcom.org.uk/radiocomms/d.../hdmasters.pdf


Pages 15-16 say about 40 Mbps of extra capacity can be used to allow 5 HD
channels using 720p on a dedicated DVB-T2 mux, and to allow this the bit
rates of existing SD channels would have to be squeezed to the tune of 8.7
Mbps in total.

Hmmmmm. So they want to use 720p, which is medium-definition, IMO, not
high-definition, and they need to squeeze the bit rates significantly,
which are already squeezed too much as it is.

It's a good job I'm planning to get satellite before 2012!! And I
sympathise with everybody not getting it! And they'd better not use 720p
on satellite!!!!

Squeezing HD into the existing muxes is ridiculous, but it may be
politically necessary for Ofcom to suggest this, in the interests of the
spectrum auction. Ultimately, keeping BBC HD and ITV HD off terrestrial will
prove politically impossible, and Ofcom will change their tune.

720p is favoured by the EU, but has no chance in competition with 1080i,
because 1080 is a bigger number. Even if the 720 picture was of higher
quality, 1080 will always sell better because it sounds like a bigger,
better, higher definition system. The TV broadcasters prefer 1080i, and will
use it assuming they get all or most of channels 31 to 40 and 63 to 68 for
HD, which is what I would hope and expect.

Conversely, if I owned a mobile phone company I wouldn't want to gear up
production for a non-standard UK-only spectrum allocation which the biggest,
richest and longest established state and commercial broadcasters wanted for
themselves. The main broadcasters would be waiting for my company to go
under, and it would be in their interests to do as little as possible to
prevent it.

HD post-switchover
 

"DAB sounds worse than FM" [email protected] wrote in message
...
DAB sounds worse than FM wrote:
There's an interesting Ofcom document about it he

http://www.ofcom.org.uk/radiocomms/d.../hdmasters.pdf


Pages 15-16 say about 40 Mbps of extra capacity can be used to allow 5 HD
channels using 720p on a dedicated DVB-T2 mux, and to allow this the bit
rates of existing SD channels would have to be squeezed to the tune of 8.7
Mbps in total.

Hmmmmm. So they want to use 720p, which is medium-definition, IMO, not
high-definition, and they need to squeeze the bit rates significantly,
which are already squeezed too much as it is.

It's a good job I'm planning to get satellite before 2012!! And I
sympathise with everybody not getting it! And they'd better not use 720p
on satellite!!!!

When I do get a hi-def flat panel I'll be happy enough with shiny silver
disks , games consoles and downloaded HD tv



--
Alex

New laptop - Sig missing

HD post-switchover
 

Mike Henry wrote:
and is vastly superior to SD.

As an opinion you're of course entitled to say that, but not state it as
if it were fact here on a technical group. I'm struggling to see even
within the confines of the English language how an increase of 25% (720
lines instead of 576) could be described is "vastly" superior. A bit of
a higher resolution, sure.

The actual vertical resolution of 720p is very similar to 1080i, both of
these are vastly superior to 576i.

HD post-switchover
 

On Thu, 04 Oct 2007 21:10:49 +0100, Mike Henry
cluelessly wrote:

As an opinion you're of course entitled to say that, but not state it as
if it were fact here on a technical group. I'm struggling to see even
within the confines of the English language how an increase of 25% (720
lines instead of 576) could be described is "vastly" superior. A bit of
a higher resolution, sure.

So the extra 560 pixels in the X axis counts for nothing?
--
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Help make Usenet a better place: English is read downwards,
please don't top post. Trim replies to quote only relevant text.
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HD post-switchover
 

On Thu, 04 Oct 2007 22:56:49 +0100, Mike Henry
wrote:

So the extra 560 pixels in the X axis counts for nothing?

Only if it's used.

Either it is 720p or it isn't.

In this wonderful SD age of broadcasting we currently
have many channels, including major national ones not just cheap
shopping channels (E4/More4/C4+1/ITV2,3,4/Five US/Five Life)
broadcasting at VHS resolutions. Given that track record they'll all do
the same with HD, as well as winding down the bitrate until it's just at
the point when people stop complaining.

Which has nothing to do with what I was referring to. When limited
bandwidth is taken into account 720p makes a lot more sense than
1080p.
--
Andrew, contact via http://interpleb.googlepages.com
Help make Usenet a better place: English is read downwards,
please don't top post. Trim replies to quote only relevant text.
Check groups.google.com before asking an obvious question.

HD post-switchover
 

Ben wrote:
Mike Henry wrote:
and is vastly superior to SD.

As an opinion you're of course entitled to say that, but not state
it as if it were fact here on a technical group. I'm struggling to
see even within the confines of the English language how an increase
of 25% (720 lines instead of 576) could be described is "vastly"
superior. A bit of a higher resolution, sure.

The actual vertical resolution of 720p is very similar to 1080i, both
of these are vastly superior to 576i.


1920 x 1080 x 0.8 = 1,658,880 pixels (1080i)

1280 x 720 = 921,600 pixels (720p)

1,658,880 / 921,600 = 1.8

The HD channels are actually using 1440 x 1080 though, so the difference is:

1.8 x (1440/1920) = 1.35

80% higher resolution or 35% higher, they're both a lot higher than 720p.


--
Steve - www.digitalradiotech.co.uk - Digital Radio News & Info