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  • Hey all, just changed over the backend after 15 years I figured time to give it a bit of an update, its probably gonna be a bit weird for most of you and i am sure there is a few bugs to work out but it should kinda work the same as before... hopefully :)

4K Monitors...

Mike, you mentioned that the bit rate for HD distribution was similar to Blu-Ray and that the primary reason the Blu-Ray versions were better was tied to more sophisticated and time consuming encoding procedures. I was under the impression that the difference in bit rate was also pretty significant as distributors cram more channels into limited bandwidth.

I waited patiently for DirectTV to switch to MPEG-4 before buying in, then got a rude awakening when the majority of what came off the bird had actually been MPEG-2 encoded along the way and then re-encoded in real time to MPEG-4 creating some ugly concatenation artifacts. Yuck.

AS the delivery of content to the consumer evolves I am hoping that we see deployment of a hybrid system where you can surf available content swiftly at lower resolutions and then when you choose a "program" it can take over a significant portion of the pipe (bandwidth). Whether its RedRay or X265 or whatever, I don't think its crazy to think that a 40mbs bit rate would support nice looking 4K with 7.1 audio. As more and more computing relies on the "cloud" I think there will be plenty of impetus to offer 50mbs download speeds to a mass market. The real question, as usual, is how long will it take?

Cheers - #19
 
Blair S. Paulsen said:
Mike, you mentioned that the bit rate for HD distribution was similar to Blu-Ray and that the primary reason the Blu-Ray versions were better was tied to more sophisticated and time consuming encoding procedures. I was under the impression that the difference in bit rate was also pretty significant as distributors cram more channels into limited bandwidth.
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I was referring to the bandwidth allocated for over the air HD broadcast, which is roughly 19Mb. It is, of course, true that the full bandwidth is rarely used by broadcast stations, who have shown a preference for multicasting, which is an option they were given when the bandwidth was awarded. The point I was trying to make is that even when the full bandwidth is used, the quality of the image and particularly motion rendition is inferior to that of material that utilizes programmed compression at a similar data rate (or even a lower data rate).
 
Blair S. Paulsen said:
I don't think its crazy to think that a 40mbs bit rate would support nice looking 4K with 7.1 audio.
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It's not crazy at all, we are currently encoding for RED RAY at 20 Mb/s to deliver 4K cinema grade images and 7.1 audio (visually lossless v's DPX source files on a 40 ft screen) and that's only just above ATSC 19.3 Mb/s payload.
 
At least for me this is crazy!.
Because i can see difference between redcode7 vs redcode14. And redcode14:1 is far more than 20mbit...
 
Simon Falkentorp said:
Also the distribution companies? Once the 4K panels are in the homes, will it take a Red Ray, or will it also be possible to play from (fast/modern) computer connected to 4K panel?
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It depends on the bit rate, that's the key question - for example RED RAY is at 20 mb/s, and I can play back PRO RES HQ 4:2:2 at 800 Mb/s on a high end Mac. Now there may be other solutions in-between these bit rate examples, but it is pretty obvious which one of these two codecs is more commercially viable for 4K video + 7.1 ch audio distribution.
 
Stuart English said:
It depends on the bit rate, that's the key question - for example RED RAY is at 20 mb/s, and I can play back PRO RES HQ 4:2:2 at 800 Mb/s on a high end Mac. Now there may be other solutions in-between these bit rate examples, but it is pretty obvious which one of these two codecs is more commercially viable for 4K video + 7.1 ch audio distribution.
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Stuart, I don't think you're really answering the question. ProRes HQ can be played back on a Mac (or a PC, for that matter) without any additional or proprietary hardware assistance. RedRay, at least as I understand it, is a complex algorithm that although the file size is small, will require hardware assistance (using Red hardware) to play in real time, just like various flavors of JPEG2000 do. So the answer at this point is probably no because the size of the file, and thus the speed of the storage delivering it, is not the relevant criteria. The complexity of the decoding is.

And although others here probably won't mention it, I would add that ProRes HQ actually exists in users' hands and has for a number of years. RedRay has been talked about for almost 2 years now, and is being talked about recently as if it's a shipping product. Except that it isn't. I'm not making any accusations here, but that is a fact. Without an actual shipping product it's a bit difficult to assess what's real, what's not, what the actual parameters are, and what applications it's suited for. Get something out there and we can then ask relevant questions.
 
I still have concerns about the other picture quality concerns about monitors. Sure, you can technically build a monitor with 4K resolution. But what's the bit-depth? How many consumer monitors out there can really handle 10-bit color? How many can actually reproduce Rec709 color space? How many can display pictures without enhancement issues or motion artifacts? How many have a wide enough contrast range that can handle rapid bright-to-dark transitions without any issues? How many can show white details without blooming out? How many consumer monitors look the same from many different angles in the room? How many can show a perfect gray scale display? How many can even show the exact same pictures, day after day, without changing over time? I think the answer is zero -- at the moment.

All of these problems are hard to solve even with very costly pro HD displays. 4K displays are even tougher. I don't dispute that it can be done; Sony's 4K projectors are very good in most respects, except maybe for cost, size, heat, and physical noise. And I have hope that maybe Red will be able to produce an affordable pro 4K projector of some kind. But I think the consumer electronics industry needs to walk before it can run; it's barely crawling with most of the awful consumer HD monitors I see out there. And I still say 4K delivery to the home is going to be difficult to do in the near future, even assuming just a 20Mbps data rate. And the chances of a new physical media format for consumers is almost impossible, given the near-collapse of video stores and mass-market chain stores in the present economy.

Given a massive change in infrastructure -- say, an ultra-wideband "FiOS-like" service available inexpensively in all parts of the country, without data caps -- sure, it's possible. But first: show me a decent consumer monitor that does all the HD basics right in terms of color, brightness, black detail, white detail, and all the other parameters. Then, do it in 4K.
 
M Most said:
Compression isn't the problem. I know that sounds a bit silly, but compression in and of itself is an enabling technology. What is the problem is when compression isn't handled in a way that maximizes its ability to do its job.

Broadcast television has some unique requirements, but one of the main ones is speed of delivery. Masters are often delivered to broadcast networks the day before or even the day of air. This is the case not only in the US, but in many territories. In the US specifically, however, post production expands to fill the time available. What I mean by this is that if a show "normally" allows about 2 weeks for editorial, followed by about 6 days for post sound, show conform, color correction, and creation of delivery masters, this time is usually expanded prior to the first airing (when there is more time available) and contracted towards the end of a season (when production is much closer to the air date). In either case, there is minimal time available for broadcast prep between creation of the delivery master and the broadcast airing. This, along with pure convenience, has led to the rather universal use of real time encoders for broadcast compression. This is then concatenated with recompression at both the cable and local broadcast level for almost all networks (Fox is a notable exception), also using real time encoding. The fact is that real time encoding has limitations, some rather severe, when compared to the kind of scene by scene, programmed compression used on, say, DVD's and BluRay discs - and also in the RedRay system, if I'm to believe what we've been told. BluRay and broadcast HD don't use vastly different data rates, but the quality on BluRay is almost always noticeably superior, especially in scenes with lots of detail and lots of motion.That's because the compression parameters are controlled and optimized on a scene by scene basis, with the primary criteria being overall file size. Eliminating real time encoding from the process, and replacing it with programmed compression, can and does lead to much higher quality at much smaller file sizes. In the early days of HD broadcast, I held out hope that since broadcast servers (largely based on JPEG2000 compression) were likely to come into wide use, that the industry would turn from creating videotape masters for broadcast delivery towards file based delivery, with enough time allotted to go through a programmed compression step and thus ensure the highest quality. That didn't happen, in part because of the time issues I mentioned, and in part because as with just about anything in the technical world these days, many people and companies want to take the easy way out as long as it's good enough. The fact is that with modern compression techniques and codecs (and I'm not talking only about RedRay here, but I'm not excluding it either) it is quite possible to deliver higher quality as well as higher resolution at data rates equal to or less than those used for real time HD encoding. But that requires a very different mindset on the part of the entire industry, from production through post through broadcast and cable delivery, in order to actually happen. I don't foresee that being the case.
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Having said that, that is yesterday, what is going to happen tomorrow. Doubling channel size or quadrupaling live compression quality results in better images in the existing frame work. How to improve live compression, well Redray might help as standard, but increases in compressor intelligence can help, before we get into an area of precompress or associated Meta files attached to footage. So, changing the live compressor could still yield improvements (though my ambarella cameras produce nice quality). Wherever rr or h264, improvements are possible.

As for the move to 4k mentioned elsewhere, moves to bigger screens will make hd look SD (sorry 720p50), those moves in screen size are possible in two years with the technology advancements. I have been meaning to make a special 200 inch+ high gain projection screen for the last 8 or so years, cheap, that can use a cheap projector source. It is based on an old design, fhd is so dead. When execs are faced with the fhd quality on their own, and their freind's, screens, aswell as a growing consumer base that might choose online redray delivery for their 4k displays, or a video shop, the desirability to change will become more obvious. Now is the time to establish (figure out) future 4k standards for this years use and in broadcast in 2-4 years time.
 
Stuart English said:
It's not crazy at all, we are currently encoding for RED RAY at 20 Mb/s to deliver 4K cinema grade images and 7.1 audio (visually lossless v's DPX source files on a 40 ft screen) and that's only just above ATSC 19.3 Mb/s payload.
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He, he!
 
I can't wait for the day that we will playback 120fps or 96fps of 4K. I think that is the thing to push from now on. We can record it with Epic. As long as peoples feedback is that they can't see the difference between 4K and 2K a lot of things are not right yet. One thing is for sure...4K is the resolution most of us here believed in. But to truely make it a show of rich detail/sharpness we will need much higher framerate to get rid of motionblur. The more motionblur will be a thing of the past, the more we will see the benefits of a hi-res imaging. We need detail in moving objects in my opinion. And I hope I'm not alone in this. 120fps5K shouldn't be only used for overcranking. It should also predominantly be a futureproof acquisition format. I hope projectors and monitors will step it up from now on!!
 
Jose Lomeña said:
At least for me this is crazy!.
Because i can see difference between redcode7 vs redcode14. And redcode14:1 is far more than 20mbit...
Click to expand...

I could probably tell you how it works, but I might accidentally tell Red how to make it better. I have worked more extensively on new compression techniques then Red, at higher target compression rates, and much lower processing requirements, years. The possibilities will amaze you, but despite that, I doubt on a 40 foot screen rr is really that vissually loss less unless you are comparing it to the existing digital cinema format. In anyway, a great effort, and one revolutionary tech.
 
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