Why 50hz and 60Hz in 4K Broadcast

[iwod]

With 4K TV Broadcast using HEVC, there will be no more Interlace Video ( Hurray ! ) and allows only 50P or 60P.

My question is why the need for choice between 50P and 60P? When today's newer TV sets they could handle even up to 120hz.

So why we still need to have two option and not just standardize on one?

[scharfis_brain]

just because legacy contents (480i, 576i, 1080i) need to be able to be re-used on 4k broadcasting.
conversion from 50hz content to 60hz just to be able to broadcast it on 4k would introduce a very unnecessary impact on image quality.

Isn't the standardization reached over the years not enough?

1) analogue video was totally incompatible (PAL vs NTSC)
2) digital SD video standardized colour coding as well as horizontal image resolution
3) digital HD 720p/1080i standardized vertical resolution as well
4) standardizing the framerate would cripple the incompatible standard

The only way a standarization would work is this:
Go to 300hz refresh rate.
It is evenly dividible by 25, 30, 50 and 60 hz.
Thus no problems will exsist by even mixing all of these framerates into a 300hz container.

[Asmodian]

The only way a standarization would work is this:
Go to 300hz refresh rate.
It is evenly dividible by 25, 30, 50 and 60 hz.
Thus no problems will exsist by even mixing all of these framerates into a 300hz container.

Or completely variable, it could even only be up to 60 Hz (8K?). I hope we will drop fixed frame rates at some point as they seem unnecessary with near future video playback equipment. :)

24 doesn't go into 300 very well, one 1/2 frame blend and 12 clean frames per frame, 600Hz it is. ;)

For now, 50p and 60p is quite nice but I hope they have something for 24fps?

[huhn]

For now, 50p and 60p is quite nice but I hope they have something for 24fps?

a deinterlaced 30i 3:2 telecine stream results with nearly all Tv out there in a 3:2 judder so no harm done by doing this directly in progressive. this should be way easier to fix for us.

[pandy]

So why we still need to have two option and not just standardize on one?

Reason is simple - this will be to expensive - side to this there is no 120Hz (300Hz) sources. And providing higher framerate and higher resolution at the same time make this all insanely expensive in reasonable - predictable future.

[SeeMoreDigital]

24 doesn't go into 300 very well, one 1/2 frame blend and 12 clean frames per frame, 600Hz it is. ;)
Why stop there... 1200Hz would offer support for everything including 48 frames per second (Hobbit anyone) ;)

[kolak]

Answer is simply: bandwidth and money.
Broadcast is not about quality, but making most possible money.

[huhn]

Why stop there... 1200Hz would offer support for everything including 48 frames per second (Hobbit anyone) ;)

don't forget that we have some movies with true 24 and most with 24000/1001.

so we need a bit more...

[raffriff42]

Fixed frame rates are a relic of a soon-to-be bygone age, says I :devil:
NVIDIA G-Sync: Death of the Refresh Rate (http://www.pcper.com/reviews/Graphics-Cards/NVIDIA-G-Sync-Death-Refresh-Rate) (pcper.com)
Frames can be displayed at any time, but it takes some advanced processing to maintain consistent brightness levels - which is why displays currently limit the frame rates they support. Arbitrary frame rate support is coming, but how soon is a question.

Gamers are driving the technology here - they want to see the display refresh as soon as a new frame is available, without waiting for the next 1/60 sec interval, or whatever that interval may be. NVIDIA G-Sync is a hardware solution aimed at OEMs which does that processing. I don't see why that tech can't also support arbitrary frames rates...hm?

[turbojet]

They should be able to get rid of 24000/1001 and 30000/1001 and use the native 24 and 30 fps can't they?

I do think things are moving towards displays handling 50 and 60hz. The few tv's I've tried in ntsc land can be forced to 50hz but it doesn't switch to it when playing 25/50 fps sources unless instructed to. Do tv's sold in pal land switch to 60/120 without forcing it?

[SeeMoreDigital]

Do tv's sold in pal land switch to 60/120 without forcing it?It's a mandatory requirement for all Smart TV's sold within Europe to be 'multi-standard'.

The end-user does not have to fiddle with any settings. It's all done automatically ;)

[turbojet]

That's good, here PAL BD/DVD's play at 60hz with judder. Custom resolution needs to be set to get 50hz. The judder is minimal compared to what happens with 60fps on a 50hz display though.

[microchip8]

That's good, here PAL BD/DVD's play at 60hz with judder. Custom resolution needs to be set to get 50hz. The judder is minimal compared to what happens with 60fps on a 50hz display though.

I also suffer from motion judder. My LG BD player has the option to be set to 24 Hz and with this enabled I can enable on my LG TV the Real Cinema option which is supposed to improve things. But I find it has no effect on the judder and is even worse than setting the BD player to 50 Hz, which my TV displays it at 60 Hz

The one outstanding film where it's really terrible is Star Wars Attack of the Clones. The scene where Obi Wan is introduced to the clones (the all white scenery scenes where they walk through the hall) looks full of judder here, when the camera slowly moves through the whole scene. It's really terrible

[huhn]

I also suffer from motion judder. My LG BD player has the option to be set to 24 Hz and with this enabled I can enable on my LG TV the Real Cinema option which is supposed to improve things. But I find it has no effect on the judder and is even worse than setting the BD player to 50 Hz, which my TV displays it at 60 Hz

The one outstanding film where it's really terrible is Star Wars Attack of the Clones. The scene where Obi Wan is introduced to the clones (the all white scenery scenes where they walk through the hall) looks full of judder here, when the camera slowly moves through the whole scene. It's really terrible
this problem could be motion blur to. and LG is not know for good motion handling at all. except you have a plasma from LG.

[microchip8]

Well, when I watch the hobbit or the lord of the rings, there is absolutely no judder at all. Everything is smooth

[microchip8]

this problem could be motion blur to. and LG is not know for good motion handling at all. except you have a plasma from LG.

Watched a few films focusing on these issues. I don't suffer (that much) from blur (where background gets blurred in fast moving scenes) but it's really the judder in some films that is noticeable

In fact, this appears a common problem in all LCD TVs so manufacturers have invented various techniques to try and reduce such judder/blur.