So as promised last week we are going to discussed about HDMI 2.1’s 8K capability, what sort of video signal is it and which customer is it targeted at?
First, let’s speculate what kind of devices would support 8K video signal and who is the target consumer. Well, as with eARC discussion last week, the 8K feature of HDMI 2.1 is targeted to very high end users. The ones who own very spacious living room and has substantial funds to buy such high end gadgets. 8K also targets facility owners (both public and private) as end users of the technology.
For example, a supermarket owner may want to setup a wide monitor inside the store to inform shoppers about product discounts in real time. Public facilities like train stations may set up 8K display to make transit lines and directions more visible to passengers. In all these scenarios can take advantages of what 8K display can deliver.
Compelling images and better visibility are the main advantage of 8K displays, so the target customer for this product are those who demand these features and has the funds to finance the high cost of installation.
4K = 1080p x 4
Most homes today (this is the middle of 2018) are still using 1080p TVs that they bought in the past years. And when you examine the signal these TVs receive via the their internal tuner the signal may be less than that, maybe around 1080i. Accurately speaking, when we say 1080p, we are pointing to progressive 1920 x 1080 dot pixel video resolution.
With the introduction of 4K, the 1080p resolution is multiplied by 4 to produce the 4K resolution which is actually 3840 x 2160 dot pixel video resolution. You are maybe wondering that the number of dot pixel was merely doubled. And what was multiplied by 4, was it the 1080p or the 1920? The answer is neither, since we are talking about area, not a single side.
To illustrate the point, let’s the following diagram:
1080p and 4K mumbo jumbo
As you could see 1920 x 1080 or FHD (Full High Definition) has quadrupled its area to become 4K UHD (Ultra High Definition). You see the 4K here is pointing to the width of the 4K resolution which is actually 3840 dot pixels (1920 doubled). Some 4K formats actually goes above that pixel number (like 4096 dot pixels wide), but that’s not the point. The point is that the “4K” term points to the horizontal size or the width of the resolution.
This is one of the reasons why people get confused with the resolution terms. During the FHD days, the marketing term was “1080p”, which points to height and not the width of the resolution. When rendering 4K videos became a reality, the marketing engines of the day just couldn’t resist the easy and appealing marketing power that the tern “4K” brings. So the term “4K” stuck. Ok, so “4K” and “1080p” mumbo jumbo is now resolved. Now lets talk about 8K format.
8K = 4K x 4
See the diagram again. 8K is just four 4K area knitted together. If you factor the fact that most homes today still owns and uses TV and monitors that max at Full HD (1080p) resolution, and most TV signals are still in the level of SD (standard definition) to HD (high definition like 720p to 1080i), the upgrade to 8K is a mind-boggling overkill!
Mind you, our TV at home usually renders 1080i TV signal and can receive and render 1080p signal coming from STB’s and BD players through its HDMI ports. I’m pretty much contented with it and I still couldn’t find a compelling alibi to persuade my wife to replace it with a new 4K model.
Now if you think about it, 8K is 16 “1080p” knitted together. So if the pixel density remains unchanged, that means having 16 units of our current 47 inch TV! Of course, pixel densities of TV panels has changed for the better so 47 inch TVs can now have 4K pixel densities.
For the most part, however, source signals have remained unchanged, so even though we’ve seen some movies at Netflix with 4K tag, TV panels usually still renders 1080p signals in most scenarios. On this regard, 4K panels today might still be an overkill.
Now, how about 8K? Can we say having it at your average homes is a quadruple overkill? Maybe. But as we already speculated above, 8K TVs are not targeted at your average homes, but at the well-to-dos and those who have very spacious living room. So your average living rooms may not have 8K TVs anyway, at least not in the near future.
Future topics about display tech.
Of course, resolution is only one part of the story when talking about panel quality and functions. Color depth, frame rates, and pixel quality all add to what resolution can provide. So in our next articles we’d like to take up these other functionalities.
Well, that’s all for our resolution discussion. We’ll see you again next week!