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Migration of Live TV to Support High-Dynamic Range Transmission

amirm

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HDR or High Dynamic Range is all the rage now on the display side. But with it, there is a big problem for broadcasters which now have to support HD with and with HDR and UHD/4K with HDR. How do they make all the feeds simultaneously look good? And how do they pay for such expensive transition?

The issue for pre-recorded content is easier in that it is off-line conversion. We know what format DVD and Blu-ray are for example. With live, the user can have anything from a tablet to HD or HDR television.

Bob post this video which shows some of the solutions to this problem and the jockeying among the usual suspects from Dolby to Technicolor and Sony for position here. It is probably way too deep of a dive for most here but the first 10 minutes or so might be useful watch. That is the presentation by Pat Griffis from Dolby who used to work on my team when I was at Microsoft (managed our standards group participation).

 

Cosmik

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Haven't watched it all yet, but it is something I have thought about before. What you don't want (IMO) is 'dynamic' contrast variations, where as a scene changes, the mapping to SDR is changing dynamically. In this case, you show a room and as a person walks under a light, the whole picture shifts in brightness, 'gamma' and contrast like a weird AGC.

I always set my TVs up without the dynamic contrast feature (that aims to give the illusion of deep blacks on a LCD by reducing contrast when the scene is dim) and I can see that with this new HDR, we may end up with that sort of queasy variation being unavoidable on a SDR TV unless controlled by the programme producers themselves on a scene by scene basis. In this case, the whole scene of the room would have fixed mapping. If this means that we need to go into a bit of clipping in the brightly illuminated face or whatever, so be it - it is 'expected' and 'intuitive' in an SDR scene.

Unfortunately, I can see that if most people can tolerate today's dynamic contrast feature (I can't) they will tolerate the weird AGC effects of dynamic mapping. And if they don't, it will motivate them to spend money on a new TV, so no problem for the TV people.
 

RayDunzl

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I see 144gb/s as a base uncompressed rate for NKK Super-Hi-Vision, with compressed rates 91mb/s for transport.

That's a pretty impressive rate of compression - 1,582:1 overall.
 
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amirm

amirm

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That's partially due to the fact that cameras are not true 8K and there is a lot of redundancy as resolution goes up (two blue sky pixels are closer together in color in 8K than in 1K).
 
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