How are channels standard and high def?

Richard Dower

Reason i ask is, isin't UPC channels compressed to death?, blocky and pixelated?
I'm wondering if HD is really HD, but just uncompressed audio/video and sold as high def?

amacachi

Richard Dower wrote: »

Reason i ask is, isin't UPC channels compressed to death?, blocky and pixelated?
I'm wondering if HD is really HD, but just uncompressed audio/video and sold as high def?

Most of it is marketing. I can tell pretty damn easily when something on Sky Sports was originally HD or SD even on my SD box. For example a couple of years ago just when WWE started broadcasting in HD, Sky still had an SD stream from them. Once Sky launched their own HD channels the quality on the SD channels improved massively too in everything, except sports they didn't record themselves, some took a while to catch up.
It was even noticeable a few years ago with the Superbowl on BBC on my 17 inch portable TV. The BBC's HD stream from the yanks kept failing and they were switching between HD and SD and even on a 25 year old telly the difference was huge.

Proper compression and the treatment of the video source is far more important than just the number of dots.

EDIT: It applies to films as well. If you watch a film in the cinema-type widescreen ratio, it's generally about 21:9. Now if someone has a TV set which is 720p and you work out how much of the screen is being used by the black bars, it generally reduces the resolution to DVD resolution. So again, it all depends on the compression of the video. Also the fact that almost any old film was shot in the equivalent of about 2160p is something I find quite ironic. :pac:

mike65

Thats why freshly minted Columbo prints on ITV look perfect.

Minstrel27

Richard Dower wrote: »

Reason i ask is, isin't UPC channels compressed to death?, blocky and pixelated?
I'm wondering if HD is really HD, but just uncompressed audio/video and sold as high def?

For a few years BBC HD wasn't at a standard that I would consider to be HD but they have improved the PQ recently. On most other channels that I have had I would say that the HD was definately noticable (eg. Sky Sports, Sky News, Eurosport HD) but I don't have them anymore

Basq

Nonsense.. Sky keep telling me:

"It isn't HD until we turn it on!"

I could be totally wrong on this - but for anything to be proper HD, it has to be filmed using HD cameras? The quality might be better on SD, but that's about it.

amacachi

Deleted User wrote: »

I could be totally wrong on this - but for anything to be proper HD, it has to be filmed using HD cameras? The quality might be better on SD, but that's about it.

Yes, but as I said, cinema stuff from even 60 years ago was recorded on film which can be transfered to a digital form at 2160p with no loss of detail. I can't remember which film type does what but a decent amount of TV could be made HD if they were arsed going back to the original prints and creating new digital copies, but all too often they're not bothered.

high heels

Sky HD is 720P

which is 720 lines but progressive which is like a film print ( so each frame is a picture) instead of 1080i which is 1080 lines but each frames is two parts so odd number lines down to 1080 is shown first then even number lines is shown in the 2nd part of the frame.

720P is better for sports as it's a full picture each frame. but drama is better in 1080i as the picture doesent have much movement like sports.

Also HD is recorded in 5.1 Suround sound.

and 90% of TV these days is shot on HD but is down graded to SD for transmission.

Minstrel27

Sky HD is 1080i

amacachi

Aye, 99% sure Sky is 1080i.

Minstrel27

I am 100%.