The following article is written by Len Davies, a contributing author at Ultra HDTV Magazine. Len is also the executive producer at Ultra HD Productions, based in Hollywood, California. He has over 30 years of production experience, and is one of the pioneers in 4K Content Production.
My First Broadcast Experience — Years Ago
Nobody actually views broadcast programmes in their native form — neither viewers nor producers. The first insight to this came several years ago when my production company in the UK was commissioned to make a programme for a major channel. I spent weeks ensuring that every single frame was a work of art, every graphic was clean and pristine and every transition was smooth. I delivered the very expensive digital mastertape to their broadcast centre and waited several weeks for the broadcast.
We had a family event at the transmission and when the programme came on I just couldn’t understand what was happening. The text had aliasing (jagged lines) and any fast action had pixelating going on. I had been authoring DVD’s for several years prior to this and I knew MPEG 2 encoding artefacts when I saw them. Not only that, but it was a low quality encoding and, I suspect, constant bit rate as the transitions were particularly bad.
After a few enquiries I found out that, indeed, the master tapes were ingested into a capture and encoding system and the programmes were broadcast from there, and it was a very low CBR MPEG 2 encoding. When producers bust a gut to deliver programmmes to specific technical specs it’s disheartening to be so disappointed.
What has this to do with 4K I hear you ask? Everything really, as the same thing is happening here but in a MUCH bigger way.
My Work in 4K Today
I work in 4K Production at Ultra HD Productions, which involves day-to-day production of daytime TV programming in 4K Ultra HD. We produce series such as “Hollywood Makeover” and “Relax California Style” that are delivered through Ladies First Distribution and “Fitness California Style” through Fighting Spirit Distribution. We handle 4K content in its true native format from camera source to final edits. It is a real pleasure for me to cooperate with the above mentioned TV content distribution companies, as they are as engaged in delivering true native 4K content to the world as am I. We see that there is a lack of 4K content on the international market and we absolutely want to be ready for the demand of broadcasters for this brand new technology.
Delivery is an Important Matter
Here comes the mathematics bit, do you know the size of a true 4K 26 minute file? Over 150GB! There is no domestic delivery system at this time that can give the viewer true 4K in its native form. Working on the figures I’ve just mentioned, a 2 hour movie would be around 600GB in size. HDMI as a delivery system is inadequate to even come close to the bandwidth required to display true 4K, and HDMI 2.0 can apparently handle HEVC and H.265 but, and here’s the thing, those are compression formats and none of it is true 4K!
The only way that 4K content can be delivered to the viewing public, as has been the case in every TV revolution in recent years, is through extensive compression. I’ve seen streamed 4K broadcast and it is stunning, but I’ve also seen TRUE NATIVE 4K — and it absolutely blows your mind. If you search for 4K capable screens, you’ll find the majority are computer displays. The only way true 4K content can be viewed from my experience is from a hard drive using Quicktime, but unless you have a truly fast data transfer it doesn’t play back smoothly yet. True native 4K content has a way to go before the public can truly enjoy it, so streaming the compressed versions is the only way we’ll be able to take the next step up from HD.
Related: 4K HEVC Video Demonstration
See Also: What is HEVC?
Let’s look at this another way. As it stands right now, apart from hard drives, the largest delivery system we have is a 50GB Blu-ray disc, with 100GB discs on the horizon. There are movies on the market that are ‘Mastered in 4K’, and while they may have been mastered in 4K from the source, they have certainly been compressed to fit the Blu-ray discs they inhabit. If I use the numbers from earlier in this article, the quality you’ll see is less than a tenth of the original file size, which must have an effect on the final product. Also if a movie made in 1920 x 1080 is suddenly stretched to fit 3840 x 2160 then we have what I like to call the ‘cheesecloth’ effect. If you take a piece of cheesecloth and start stretching it then holes will start to appear. Take into account that HD has over 2 million pixels in its span, and Ultra HD has in excess of 8 million. One HD pixel now has to cover the space of 4 Ultra HD pixels, and even though the process can be very effective, weaknesses do show.
4K is the Next Standard
I am one of the blessed few that have the pleasure of working with Native 4K on a daily basis. Join the Ultra HD movement by all means as it’s going to be a magnificent journey and those with 4K TV’s will be able to witness all of the new content that has to arrive sooner rather than later. I will no doubt end up buying all my favourite movies in compressed 4K formats as I passionately thrive on the next big thing.