Openreach engineers 4th visit...

[Vir Campestris]

It was the sparse nature of the village which caused BT to give us a fibre. Couldn't get a fast enough speed from FTTC to get the subsidy payments.

Andy

[Vir Campestris]

Old fashioned "625 line" TV was actually 576 (the rest were flyback) and I don't recall the number of horizontal pixels - 4/3 of 576.

We went widescreen, and HD - which gave us 1920x1080. (sometimes only

720 lines)

4k is twice that, and 8k twice again. Sharper pictures.

There's also HDR floating about - better colour rendition, 10 bits per colour instead of 8. It all needs more data.

That's another question entirely. Unless you have a DAMN big screen and sit really close you don't need the pixels.

HDR is nice though - on the odd occasion you can find the stuff to watch. No solarisation.

Andy

[Tim Streater]

HD is certainly nice which is presumably 16Mbps or so uncompressed.But I assume it's compressed down to a lot less than that, no?

[brightside]

Lots Not from any electorate Not for any electorate Not any electorate You can't.

Welcome to the EU

[Dave Liquorice]

A full 10 bits or 8 shifted as required? I thought the later.

er, no. just doing the mutiplications 1920*1080*3*8*25 gives 1.2 Gbps raw.

Just a little, I think DSAT HD runs at 5 to 10 Mbps, that's fairly watchable. iPlayer squishes it down to below 3 Mbps, the artifacts start to show but are not distracting. I can't watch Freeview as the artifacts are too distracting. Blueray off disc is around 40 Mbps.

[Andy Burns]

Virgin have got an offer on at the moment, 120GB/month @ £20.

[Dave Liquorice]

I can see all four networks (EE, Vodafone, 3 and O2) without any trouble. Which MVNO you use can restrict what you can access. I have a TPO SIM on EE but can't get 4G. The Asda Mobile SIM also on EE can...

[Dave Liquorice]

Sarcasm...

[Dave Liquorice]

That would do capacity and cost wise but whose network to Virgin use?

<digs> EE and 4G, good. 12 month contract not so good. Static IP address? rDNS on that address? Need those to consider it as a main connection and paying anything for a backup unless I actually use it is a no no.

[The Natural Philosopher]

there were no pixels. It was 'analogue'

Roughly 6Mhz B&W bandwith, which divided by the 25 x 625 line scan frequency is about 384 reasonable transitions per line.

[The Natural Philosopher]

1920x1080 x 3 bytes deep is over 6 megabytes per frame, raw. Now multiply that by 25Hz and get 1.2Gbps as the raw transfer rate needed.

Of course its compressed.

[The Natural Philosopher]

Well Nyquist/Shannon and all that.

we are always pushing the Nyquist/shannon limits. Adsl2+ gets a bit closer, that is all.

I think its a great improvement mainly because it doesnt need to retrain to change speed slightly. It constantly monitors the bins and adds bits or removes tham if it can/needs to.

The BRAS has also gone IIRC. Or at leats is not so coarse and agressivley appiled. You get download pseeds a far nearer the sync speed.

[Tim Streater]

Ooops. I was nodding off there all right. :-(

[Vir Campestris]

What comes off a DVD is pixels. So is "standard definition" broadcast TV.

(They are of course an emulation of the original analogue transmissions)

Andy

[Steve Walker]

Yes, but get up close to the screen and you could see the individual triads of coloured phosphors. The sweeping of the electron beams and their strength may have been analogue, but the display was of discrete triads, energised through the tiny holes in the shadow mask or aperture grille - effectively little different to pixels.

SteveW

[The Natural Philosopher]

Not on a black and white TV there werren't.

Anyway, that is totaky irrelevant as the broadcast signal was pixel free and only of enough bandwidth to allow about 300 horizintal dots to be shown. Even with an infite number of shadowmask holes.

.

[spuorgelgoog]

But you could still see every blade of grass, whereas on digital the grass merges into a smeary green thing.

Owain

[The Natural Philosopher]

Well that depends...

Bear on mind that that 6Mhz video rate was - with say 30dB SNR - something like 480Mbps equivalent rate.

I am not sure what DTV started out with, but it wasnt that much.

Currently HDTV is around 20Mbps I think. No doubt someone knows exactly.

[Andrew]

You mean when we invite the Dali Lama over for another official visit :-)

[Andrew]

Moving all your savings to a 'safe' account :-)