SKY HDTV Demo Clips

BIGbungle · 20 Feb 2006 at 21:48

Ive downloaded the demo hdtv clips from http://www.sky.com/hd/

there are a 4 clips 2 download it looks amazing on my 43" plasma wow

TriedandTested · 20 Feb 2006 at 22:17

Have a look at these too...

http://www.highdefforum.com/showthread.php?t=6537

Sclodion · 21 Feb 2006 at 22:23

Bear in mind these are WM9 HD encoded @ ~10 mbit and as such cannot actually be taken as truely representative of the quality that Sky will be broadcasting their HD content at, which will be MPEG2 not MPEG4 or WM9, somewhere between 10 -18 Mbit variable rate, depending on the value of the content.

philhoole · 21 Feb 2006 at 22:49

Sky will broadcast HD in mpeg4/H.264

BIGbungle · 21 Feb 2006 at 23:48

Sclodion said:
Bear in mind these are WM9 HD encoded @ ~10 mbit and as such cannot actually be taken as truely representative of the quality that Sky will be broadcasting their HD content at, which will be MPEG2 not MPEG4 or WM9, somewhere between 10 -18 Mbit variable rate, depending on the value of the content.

does this mean sky hd will be better than wmhd?

Sclodion · 22 Feb 2006 at 00:08

philhoole said:
Sky will broadcast HD in mpeg4/H.264

How the hell did I miss that... I work with a lot of US broadcasters who are all doing HD with MPEG2, completely passed me by that the HD from sky would be MPEG4 AVC, although I will be very interested to see if they actually are going MPEG4 from the outset as there are very few real time HD MPEG4 encoders on the market at the moment and those that are there need a lot of work to be as good as their SD counterparts.

MrM3 · 22 Feb 2006 at 10:56

Sclodion said:
How the hell did I miss that... I work with a lot of US broadcasters who are all doing HD with MPEG2, completely passed me by that the HD from sky would be MPEG4 AVC, although I will be very interested to see if they actually are going MPEG4 from the outset as there are very few real time HD MPEG4 encoders on the market at the moment and those that are there need a lot of work to be as good as their SD counterparts.

reason why it is going to be expensive...

tom_nieto · 22 Feb 2006 at 11:45

The clips on the sky website are awesome. A whoe rugby game in that sort of detail would be sweet, like being on the pitch! I'm going to need to buy a new computer at some stage to view proper HD content when it comes out. It takes a good second or two to stop jittering

SKY HD will be sweet, but I don't think I'll be able to watch it over DVI on my 2405 by the sounds of it, oh well, I'll have to get a new TV when it comes out

Attu · 22 Feb 2006 at 14:25

MPEG4 is aparantly also one of the reasons why Sky HD has been delayed as there is a world wide shortage of the chips, as far as im aware its imposible for them to start using MPEG2 and then swap over to MPEG4 without replacing all of their equipment including the Sky HD boxes in peoples houses.
This I belive it the situation the US broadcasters are in at the moment, they started using MPEG2 but are now migrating over to MPEG2.

Sclodion · 22 Feb 2006 at 14:45

Attu said:
MPEG4 is aparantly also one of the reasons why Sky HD has been delayed as there is a world wide shortage of the chips, as far as im aware its imposible for them to start using MPEG2 and then swap over to MPEG4 without replacing all of their equipment including the Sky HD boxes in peoples houses.
This I belive it the situation the US broadcasters are in at the moment, they started using MPEG2 but are now migrating over to MPEG2.

The set top box chips that are mpeg4 capable will also decode mpeg2 so they will work with the current sky digital transmissions and would also decode HD mpeg2 should sky broadcast it. But done more research today and indeed the shortage of decoder chips for the STBs is a big issue for sky.

BIGbungle · 23 Feb 2006 at 15:55

are the HD clips avalible on the xbox360 mpeg2 or mpeg4?

Energize · 23 Feb 2006 at 23:50

Why do sky boxes use special chips, when computer cpus can do the same job but are much cheaper?

tom_nieto · 24 Feb 2006 at 00:03

They do use special chips, but if you buy 100000 of them they'll be cheaper than buying an equivalent number of p4 chips (or whatever) then programming the software.

Sclodion · 24 Feb 2006 at 00:12

No PC processor on the market today can do HD MPEG4 decoding on its own. It can be done with the assistance of hardware mpeg4 decoding on the gfx card but you're looking at £3-400 worth of processing power to do it with PC bits, minimum.

The FPGA chip that sky are using to do the HD decode is dedicated silicon and costs about about $50 a piece in massive volume, made by a company called sigma. So, no, PCs are not cheaper.

Energize · 24 Feb 2006 at 00:45

Sclodion said:
No PC processor on the market today can do HD MPEG4 decoding on its own. It can be done with the assistance of hardware mpeg4 decoding on the gfx card but you're looking at £3-400 worth of processing power to do it with PC bits, minimum.

My graphics card has no mpeg4 decoding hardware on it afaik and I can play 720p video fine on my athlon 2600 at about 70% cpu usage. My cpu only cost £60. So there should be no reason for a sky box to cost the estimated £400.

Sclodion · 24 Feb 2006 at 01:29

Energize said:
My graphics card has no mpeg4 decoding hardware on it afaik and I can play 720p video fine on my athlon 2600 at about 70% cpu usage. My cpu only cost £60. So there should be no reason for a sky box to cost the estimated £400.

Think you got the wrong end of the stick there mate. A dedicated piece of silicon is always going to be cheaper (and better) than a generic processor at a specific job, hence an HD decoding FPGA costing a lot less than a PC processor, but being far better at the decoding job. So no, a set top box will never cost anything like $400.

Of course, that PGA can only do that one job, wheras a pc processor is designed to be a generic workhorse.

But the point is that the $50 FPGA will be better than the $400 PC setup at decoding HD as that is solely what it designed to do.

Caged · 24 Feb 2006 at 03:04

Energize said:
My graphics card has no mpeg4 decoding hardware on it afaik and I can play 720p video fine on my athlon 2600 at about 70% cpu usage. My cpu only cost £60. So there should be no reason for a sky box to cost the estimated £400.

I'd love a nice loud fan in my set top box as well.

Energize · 24 Feb 2006 at 03:57

Sclodion said:
Think you got the wrong end of the stick there mate. A dedicated piece of silicon is always going to be cheaper (and better) than a generic processor at a specific job, hence an HD decoding FPGA costing a lot less than a PC processor, but being far better at the decoding job. So no, a set top box will never cost anything like $400.

Of course, that PGA can only do that one job, wheras a pc processor is designed to be a generic workhorse.

But the point is that the $50 FPGA will be better than the $400 PC setup at decoding HD as that is solely what it designed to do.

I realise that but whats going round everywhere is that the box will cost £300-400 thats what I dont understand because you could get a pc capable of decoding hd for less than that.

Caged said:
I'd love a nice loud fan in my set top box as well.

Thats what passive cooling is for

You can barely hear the media center in our front room when the tv is off.

Raider · 24 Feb 2006 at 08:23

When you play these Hi-Def clips on your PC, do you use any software? Or just WMP?

Sclodion · 24 Feb 2006 at 12:18

Raider said:
When you play these Hi-Def clips on your PC, do you use any software? Or just WMP?

WM player 9 and above has the HD codec built in. If you use something else like VLC or windows media player classic, you'll need to downloada codec pack that has the WM9 HD codecs in.