We have already covered 4K TVs in quite the depth in the past. We discussed how the PS4 Pro is not only a 4K gaming console, we put a guide together for when the time comes to buy a 4K TV, and we even discussed 4K TVs for gaming. What about those TV users who want to watch 1080p (HD) content on their 4K (3180×2160 – UHD) TV? Is the difference even noticeable? Let us take a look at 4K TV upscaling and see just what goes on behind the scenes on a 4K TV.
4K TV Upscaling
A 4K TV has the resolution of 3840×2160. This means that it is in theory four times the resolution of HD. Other than an odd Netflix show here and there, everything we watch nowadays in South Africa is HD. Technically speaking, if you had to look at your TV screen and imagine it divided into 4 boxes, only one of those boxes on the TV would have picture. That is the size of HD, and that is the actual resolution of the image you are seeing on your 4K TV. So what does a TV do to make the HD image fit your 4K display?
Inside most TVs there are various parts at work constantly that process the image sent from the HDMI cable, to the TV, and then to the display. LG, Samsung, and Hisense TVs all have processors (CPU) inside them that work non-stop to get that image to fit nicely on your TV. How it works is that every image has a border, and that border is then sampled by the processor which stretches the borders to fit the display. Basically filling up all four of those display boxes we asked you to imagine earlier. The processing does not stop there though as the image is then scanned and further enhanced even more. The TV looks for edges on the image which have now been upscaled to fit the display, and refines these edges to make them look sharper. This is vital to the 4K TV upscaling process, because after the image has been boosted up in size, it is blurry due to the low resolution now stretched to fit the higher resolution 4K screen. Think of it like a photo that you want to edit and crop for your profile picture on Facebook. The more you zoom in, the worse the image looks. During the 4K TV upscaling, the TV does the same by zooming in on the image to get it to fit on the display.
Apart from finer edges, a method called interpolation also takes place during 4K TV upscaling. The TV detects pixels on the image, and based one the pixels, duplicates the pixels around it by 4. This will create four times the pixels per pixel on the TV, which will automatically upscale the image, and with the extra pixels, create a more life-like image to look at. The PS4 Pro, for example, makes use of this feature in many games. Developers have used a method called “Checkerboard” 4k TV upscaling, which is similar to interpolation. The game engine detects the pixels and multiplies them to render a higher resolution image. So where there is a blue pixel, and a red pixel next to each other, the pixels are multiplied like a checkerboard.
Does 4K TV Upscaling Work?
4K TV upscaling does work. Without it, images on a 4K TV would look terrible. However, different TV sets offer different results when it comes to 4K TV upscaling, and it will always be better to view a 4K image on a 4K TV rather than an HD image on a 4K TV. Always look around when buying a 4K TV for sets that offer some sort of 4K TV upscaling feature. Some of them will have dedicated CPUs in them that accomplish 4K TV upscaling, while others will just mention that they do upscale images. It is also important to remember that upscaled HD content for a 4K TV is not 4K, and it will always be better to view 4K content on the display, but if you don’t have 4K streaming, then upscaled HD content is as good as it is going to get.