DVD vs HD
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elDiablo
Guest
That is pretty amazing! Cheers for the share!
DeZmond
Junior Administrator
Awesome stuff, I've been wondering what HD actually looked like (having never seen one in person) - that's pretty amazing! I also like the way HD has been resampled down to SD format and it still looks better - excellent stuff 
- now I just hope the MPEG processor on my graphics card is up to playing HD...
- now I just hope the MPEG processor on my graphics card is up to playing HD... [THN]Buffalo_Hunter
In Cryo Sleep
Just a shame that all the "HD ready" TVs around now only support 720 lines and not 1080. My other concern, mainly with terrestrial signals, is how reliable the signal is going to be. Even my Freeview box loses the signal occasionally and that's with a low data rate (at least compared to HD it is). I guess cable is the way forward.
DeZmond
Junior Administrator
Do you know what the data rate for HD is? I'm not sure myself, but what I do know is that SD at DVD quality is ~4Mbits/sec video - that's for both your standard DVD and apparantly, the broadcast data rate also. However since it's encoded in the now-becoming-ancient MPEG-2 format it needs a high data rate to maintain quality.
Why everyone can't agree that DivX is the best thing ever and make it universally standard I don't know.
Also the reason the new "HD Ready" TVs use only 720 lines is that it's much cheaper to manufacture but they can still claim it's HD.
Also I hate the new connection system - HDMI. I posted something about that on Tech a few months back - basically it uses symmetric key encryption to ensure that you can't split your video signal.
Why everyone can't agree that DivX is the best thing ever and make it universally standard I don't know.
Also the reason the new "HD Ready" TVs use only 720 lines is that it's much cheaper to manufacture but they can still claim it's HD.
Also I hate the new connection system - HDMI. I posted something about that on Tech a few months back - basically it uses symmetric key encryption to ensure that you can't split your video signal.
The point you make Buffalo_Hunter is a potent one. Most, if not all the HD ready TV's will not support the 1080i resolution which sky will be transmitting as well as the 720p resolution.
I feel sorry for the ignorant public out there who are buying the so called HD tv's not knowing that 768 lines (Y axis) is more than sufficient for one standard but sadly lacking in the other.
I have read and heard that TV manufacturers will start as early as next year to supply TV's that have 1024 and 1200 lines. Personally I still wouldn't settle for 1024 lines, make sure it is above 1080 lines. I intend to buy a HD tv but only once it has 1080 lines or more. The model I lintened to buy next year is the Philips 50" Plasma with digital natural motion. The current model (768 lines) can be got for around £2.5K on the internet.
It is exciting but be patient and tell everyone you know as well, forking out this kind of money, you want to make sure you are going to be able to enjoy both the standard HD resolutions to the full.
Also it is worth pointing out that there are very few channels on sky transmitting in HD at the moment. Last count, I counted about 7 or 8. Next year there will be much much more.
I feel sorry for the ignorant public out there who are buying the so called HD tv's not knowing that 768 lines (Y axis) is more than sufficient for one standard but sadly lacking in the other.
I have read and heard that TV manufacturers will start as early as next year to supply TV's that have 1024 and 1200 lines. Personally I still wouldn't settle for 1024 lines, make sure it is above 1080 lines. I intend to buy a HD tv but only once it has 1080 lines or more. The model I lintened to buy next year is the Philips 50" Plasma with digital natural motion. The current model (768 lines) can be got for around £2.5K on the internet.
It is exciting but be patient and tell everyone you know as well, forking out this kind of money, you want to make sure you are going to be able to enjoy both the standard HD resolutions to the full.
Also it is worth pointing out that there are very few channels on sky transmitting in HD at the moment. Last count, I counted about 7 or 8. Next year there will be much much more.
Macca
Member
If I had the chance of watching a movie on a normal TV that cost 3 or 4 hundred pounds or watching it on one that cost 2500 quid then I would deffinatly opt for the cheaper option. I don't really see the point on spending so much money on a TV for a bit better quality untill they start making most movies in 3D or something then it doesn't really enhance the experiance that much.
Tetsuo_Shima
In Cryo Sleep
Macca said:
Agreed, Macca. And plus, once you buy that 1080i HDTV, I wonder when the 1800 TV is coming out? And then after that, the 3500? And then two screens? And then ... some other minor upgrade. Like i said before, something really major needs to happen to keep the whole thing going. Like the Heliodisplay or virtual reality or something.
Pestcontrol
In Cryo Sleep
iirc the datarate of an mpeg2 hd stream is something like 12 mbit for 720 and 20 mbit for 1080, in the US, where the native NTSC system is of inferior quality compared to the PAL system used in europe, the upgrading process has been underway for a few years and broadcasts are mostly in 720.
Europe's lagging behind technically, but it looks like the hdtv broadcasts deployed here will use h264 MPEG-4 based encoding and 1080i signals, which is much more efficient than mpeg2.
For the data rates of terrestrial broadcasts, have a look at the table at http://en.wikipedia.org/wiki/DVB-T Cable may be the way forward in any vaguely urbanized area, but outside of that you won't be stuck with poor quality. Assuming you don't live in some valley with no reception.
And then there's iptv, providing DSL technology improves to the point where it can reliaby deliver the bandwidth needed to most customers, it will be a third solution.
As for HD-Ready tv's, the point is 1080 lines instead of 720 only make a difference if you have a big enough screen, or sit close enough to it. HD-Ready tv's can take 1080 signals and downsample them, anyway.
Likewise with even higher resolutions... what's the point? Until someone invents pixel paint and 90% of the population starts using their entire wall as TV, there's simply no point. 1080 will serve us for decades to come.
Europe's lagging behind technically, but it looks like the hdtv broadcasts deployed here will use h264 MPEG-4 based encoding and 1080i signals, which is much more efficient than mpeg2.
For the data rates of terrestrial broadcasts, have a look at the table at http://en.wikipedia.org/wiki/DVB-T Cable may be the way forward in any vaguely urbanized area, but outside of that you won't be stuck with poor quality. Assuming you don't live in some valley with no reception.
And then there's iptv, providing DSL technology improves to the point where it can reliaby deliver the bandwidth needed to most customers, it will be a third solution.
As for HD-Ready tv's, the point is 1080 lines instead of 720 only make a difference if you have a big enough screen, or sit close enough to it. HD-Ready tv's can take 1080 signals and downsample them, anyway.
Likewise with even higher resolutions... what's the point? Until someone invents pixel paint and 90% of the population starts using their entire wall as TV, there's simply no point. 1080 will serve us for decades to come.
I certainly agree that "1080 lines will defintely serve for decades to come". Considering the last upgrade was in the early 1960's where they went from 425 lines to 625 lines. 625 lines is adequate for TV's for say up to 14 or 16 inches. Any bigger than that and the cracks do begin to show and lack of detail can be seen.
The simple fact of the matter is the bigger the TV screen the more lines that are required to maintain the detail. For example it would be ludicrous to spend £3000 on a tv to watch the current 625 lines standard. You don't get any more detail, the images are simply just bigger.
I have seen both 42" and 50" HD displays. IMHO the HD does enhance the experience of watching a film for two main reasons.
a) The images are bigger making it feel more immersive and cinematic - why do you pay £5 to go to the cinema?
b) The detail is very much there, you can make out tiny details you wouldn't be able notice on smaller screens with 625 lines. In this it makes what you view look more realistic.
So in short, HD and big TV's provide more realistic and immersive viewing.
The other point that pestcontrol makes about current HD tv's downsampling the 1080 lines to 720. Most TV manufacturers are dealing with this by taking every other line in 1080 lines, ie downsample from 1080 to 540 and then interpolating up to 720 lines. So effectily only 540 of the true 1080 HD lines are being used. This actually means giving less picture quality than the current 625 lines!!
If you are interested in this, you may want to check out the web yourself and decide for yourself. I for myself as I stated in my earlier post think it would be more than sensible to wait until HD tv's have at least 1080 lines so you don't having anything downsampled.
Can a HD picture that is downsampled in lines really be true HD?
The simple fact of the matter is the bigger the TV screen the more lines that are required to maintain the detail. For example it would be ludicrous to spend £3000 on a tv to watch the current 625 lines standard. You don't get any more detail, the images are simply just bigger.
I have seen both 42" and 50" HD displays. IMHO the HD does enhance the experience of watching a film for two main reasons.
a) The images are bigger making it feel more immersive and cinematic - why do you pay £5 to go to the cinema?
b) The detail is very much there, you can make out tiny details you wouldn't be able notice on smaller screens with 625 lines. In this it makes what you view look more realistic.
So in short, HD and big TV's provide more realistic and immersive viewing.
The other point that pestcontrol makes about current HD tv's downsampling the 1080 lines to 720. Most TV manufacturers are dealing with this by taking every other line in 1080 lines, ie downsample from 1080 to 540 and then interpolating up to 720 lines. So effectily only 540 of the true 1080 HD lines are being used. This actually means giving less picture quality than the current 625 lines!!
If you are interested in this, you may want to check out the web yourself and decide for yourself. I for myself as I stated in my earlier post think it would be more than sensible to wait until HD tv's have at least 1080 lines so you don't having anything downsampled.
Can a HD picture that is downsampled in lines really be true HD?
Pestcontrol
In Cryo Sleep
Heh, i thought the last upgrade was colour TV.
PAL may use 625 lines, but only 576 of them carry an image and not all of them are drawn visibly, either (this is called overscan). With digital standards, no lines are wasted. Quarter res 1080 would be similar to broadcast quality, maybe slightly less than a good dvd.
Granted though, i wasn't aware HD-Ready tv's resize the image in such a wasteful manner, it's atrocious for a tech head like me.
When you consider every computer graphics card manufactured since ~1998 was capable of resizing images of any resolution up to the screen res, in hardware, it doesn't seem very hard to include the same functionality in a TV anno 2006.
To answer your question, if a HD picture is downsampled, i'd still consider it to be HD if it's actual resulotion is higher than Standard Definition. For TV's downsampling 1080 content to 540, the answer would be no, but if it retains anything over 576 lines of detail, i'd say it is HD.
PAL may use 625 lines, but only 576 of them carry an image and not all of them are drawn visibly, either (this is called overscan). With digital standards, no lines are wasted. Quarter res 1080 would be similar to broadcast quality, maybe slightly less than a good dvd.
Granted though, i wasn't aware HD-Ready tv's resize the image in such a wasteful manner, it's atrocious for a tech head like me.
When you consider every computer graphics card manufactured since ~1998 was capable of resizing images of any resolution up to the screen res, in hardware, it doesn't seem very hard to include the same functionality in a TV anno 2006.
To answer your question, if a HD picture is downsampled, i'd still consider it to be HD if it's actual resulotion is higher than Standard Definition. For TV's downsampling 1080 content to 540, the answer would be no, but if it retains anything over 576 lines of detail, i'd say it is HD.
DeZmond
Junior Administrator
An interesting point to note here is that the link that has been provided shows a clear difference in picture quality from a native Standard Definition picture and a downsampled High Definition picture - the Lord of the Rings map looks fantastic on the downsampled image while looking blurry on the standard image.
Based on that image quality test, I'd even take the downsampled content over standard content any day.
Also, we've now got a 42" 720p HDTV (Toshiba) which does look pretty good, however with SD broadcasts it has to muck about with the display ratio and pixel placement, which means it doesn't look too fantabulous with standard content - however small writing is much easier to read than on standard definition.
Based on that image quality test, I'd even take the downsampled content over standard content any day.
Also, we've now got a 42" 720p HDTV (Toshiba) which does look pretty good, however with SD broadcasts it has to muck about with the display ratio and pixel placement, which means it doesn't look too fantabulous with standard content - however small writing is much easier to read than on standard definition.
