UPscaled Is Not 4K

My 2 Cents

Many of us have spent large amounts of money on upgrading our systems to watch 4K, wide color gamut, high dynamic range movies. AND of course those illusive 4K TV/cable and Over The Air (OTA) channels.

It has come to my notice, and maybe yours too, thet many movies are being released as UPscaled 4K. They were either never produced at a 4K or higher resolution or if they were they are often sub-sampled to 2K in order to add CGI and especial effects and then up-sampled back to 4K.

Also, many 4K cable feeds are provided at bit rates as low as 20,000,000 bits/s, Over The Air (OTA) ATSC3.0 supporting up to 57,000,000 bits/s. How can that be true 4K, when native 4K requires up to approximately 18,000,000,000 bits/s (3840×2160, P60, 8bit, 4:4:4)? 4K Blu-ray UHD plastic media supporting up to 144,000,000 bits/s. Even the lowest 4K native data rate, 3840×2160, P23.98, 10 bit, 4:2:0, requires approximately 9,000,000,000 bits/s. The new maximum HDMI 2.1 link speed for 8K/10K caps out at 48,000,000,000 bits/s. See here for HDMI 2.1 link data rates.

While I accept that modern compression technologies, like Advanced Video Coding (AVC), and Display Stream Compression (DSC) for 8/10K, can work wonders reducing bit rate by throwing away redundant frame information, perceptual encoding and reducing HF detail, a 4K compression rate of 900:1 or more, no matter how well executed, can be clearly seen on a large screen.

Some (many) new movies are shot at 4K or even 8K, however, due to the vast number of CGI and special effects that need to be added they are often sub-sampled back to 2K in order to keep the costs of creating UHD CGI effects within bounds and low enough to meet the films budgets. Either the movie is 4K or it is not and it now appears that many are not. It’s a bit like streamed 4K; these streams are so highly compressed that even with modern AVC compression techniques they are clearly not the same visual standard that can be achived from a genuine 4K plastic Blu-ray disc at bit rates of up to 144Mb/s. – NO residential delivery system compares to the media quality that a 4K UHD Blu-ray plastic disc can provide.

I can forgive old movies not being rescanned as 4K, WCG, HDR, even if they are still available as celluloid copies, but not newley produced big budget, big action movies. If it wasn’t produced in 4K, WCG and HDR it isn’t a true 4K movie but a facsimile of one.

While modern technology can provide excellent 2K up-conversion, with few artifacts, to 4K HDR material, and expand the SMPTE 609 to DCI-P3 color space its NOT REAL 4K. Much of the original data was lost or is just not there and the hardware, or AI, is interpolating (guessing) at data to create the final product. (sometimes doing a very good job).

Let me say that some of the upconverted 2K material that I own looks excellent in 4K and some even better than native 4K.  But my point here is that it is not native 4K which is what we all bought into. Its only just a little better than saying that up-converted SD to HD is HD……that is so far from the truth its laughable.

As for OTA ATSC 3.0 4K broadcasts just like we have now with HD ATSC 1.0, that is still a ways off into the future. Why? Because it doesn’t bring a broadcaster any more revenue UNLESS they have to upgrade in order to compete for eyeballs. Even today many of the HD OTA and cable channels are still broadcasting up-converted SD material. Putting an up converter on an SD or HD source doesn’t magically make 4K, today or any day in the future. You cannot “make a silk purse out of a sows ear”.

Creating native 4K material and sending it to the home at compressed bit rates that approach Blu-ray is very costly, even with todays modern technology, and I DO NOT see it becoming main stream for cable or OTA in the near future. As for 8K, it will be a long time before, if ever, it appears on any physical media format or is sent to the home at bit rates that can provide a worthwhile image improvement.

Movie houses should spend their money on getting 4K production up to snuff and manufacturers need to finish off the development of 4K before even thinking of a new higher resolution standard that really brings virtually NOTHING to the typical home viewer. Take a look at Gemini  Man in 4KP60. Even if you find the presentation a little different because you are used to viewing 4KP24 a “film style format”, the movie is technically outstanding and in my opinion a visual feast.

At least the adoption of immersive sound seems to be going well, and has been implemented extensively on most new and many re-released movies. Why? Because its inexpensive to mix or do a re-mix and it creates another ‘bell and whistle’ that makes a re-release more attractive to the prospective purchaser. After all, you just spent even more money on all those speakers and a new receiver so you want to buy media that justifies the expense.

Native 4K has a long way to go before it becomes mainstream, especially at bit rates that approach that of physical media. As for 8K, that is somewhat of a pipe dream for now, especially with regard to any form of disc media.

It is notable that during this COVID pandemic how many old movies are being re-released in 4K . Celluloid movies are being rescanned in 4K, the proper way to do the re-release, and where no such format is available the original video masters are being up-converted to 4K. Many of these re-releases also have new immersive sound mixes added. Hopefully this will keep the movie houses, film studios and media plants afloat until they can get back to the production of new 4K movies.

See here and here for my posts on ATSC3.

See here, here and here for my posts on 8K.

See here for my post on immersive sound formats.

See here for a review of 4K web/cable streaming rates.