UHD In a Hybrid SDI/IP World

HOLLYWOOD, CALIF.—On Tuesday, Oct, 27, during the annual SMPTE conference here, Randy Conrod, senior product manager of digital products for Imagine Communications and Nigel Seth-Smith, with the Signal Integrity Products group for Semtech in the U.K., will present a paper on deploying the UHD format in a hybrid SDI/IP environment. Broadcast Engineering Extra talked with Randy, Nigel and John Hudson, director of Strategic Technology and New Business Development for Semtech (who collaborated on the paper) about this issue that is growing in importance to the broadcast industry.

Broadcast Engineering Extra: What will you be covering in your session?

Randy Conrod

Randy: You’ve got a lot of marketing efforts around this transition to IP and at the same time you’ve got the UHD format being introduced to the industry as well. So with these two things at once, interfacing everything together becomes a challenge. How are we going to make all of this work? How are we going to interconnect everything? The intent of this paper was to outline what standards are being developed, what interop is taking place and then give the audience an idea of what’s there and where we’re going with all of this.

BEE: What is the biggest challenge broadcasters face in adopting UHD in an SDI infrastructure, and does it have to be hybrid?

John: You can certainly make an entire SDI infrastructure in support of UHD. There are challenges in trying to do an all IP-UHD infrastructure, but technically, even that’s possible. But realistically, today, a hybrid of the two is definitely the way to go, if UHD is the driver for a new infrastructure, especially if you want to transition to the benefits of IP in the future. Today, if you want to do ultra high-definition baseband, UHD-SDI is actually the only standardized interface that will allow you to connect UHD equipment in an interoperable way.

BEE: Would you describe what we’re going through as a transition?

John: Personally I think so, in fact it’s a transition that’s been in progress for about 18 years. I think a lot of people who are a bit new to the industry see what’s happening now and think it’s all new and that it’s a revolutionary change, but it’s actually been in progress for a very long time now. If you think about the transition to file-based workflows from tape-based workflows and how long ago that started, you can see where the birth of this sort of transition really began. So I think it is a transition, and it’s a transition that’s been in progress a long time. It’s heating up now; after 18 years of development, it’s coming to a point of really taking off.

Nigel: The capability of IP increases in terms of the cost effectiveness and the data transport capability, but at the same time, the requirements for video move on. So SD moved to HD and made the data challenge multiplied by five, and of course, UHD takes it up by another factor of four, so that has to be taken into account. But as IP becomes better able to transport video signals, the difficulty of the video signals increases as well, so that’s the UHD factor in this whole discussion, which will be part of the presentation.

Nigel Seth-Smith

BEE: How important is the SMPTE 2022-6 standard is in facilitating this transition?

John: It’s absolutely key and critical to the use of video-over-IP for live contribution links. The transition to a networked-based infrastructure for file-based workflows has been going on for a long time, but I think 2022-6 has been critical to creating interoperability for live video-over-IP. Originally, it was designed for contribution links as we know, but it has been so effective, it is finding uses elsewhere. At the moment, 2022-6 is limited to HD and baseband, but there are ways it can be expanded to support ultra high-definition going forward.

BEE: Has 2022-6 built in obsolescence?

Randy: We’re seeing [it] as an evolution going forward. Imagine has been involved in the standards and interop testing. For example, at IBC, there was a demonstration of 2022-6 interopability between Imagine Communications and EVS. One of the aspects of 2022-6 is that your video and audio and metadata are wrapped up together, so there’s a move for adding AES-67, so now in the IP domain, you can switch your video and your audio separately from each other, especially in production. The notion of obsolescence means that 2022-6 would be gone. Well, that may happen well into the future, but I definitely think we will be evolving going forward.

BEE: Can HDR be implemented in this hybrid environment?

Randy: Absolutely.

Nigel: If you look at any of the standards that are being developed, they all have the capability to transport HDR.

BEE: Are there other standards that you will be talking about, that are being developed by SMPTE to enhance the ability of SDI to handle UHD?

Nigel: There’s a working group within SMPTE that’s been in place for the last couple of years—which I chair, actually—that has been developing UHD standards for SDI. The relevant standards are ST2081 and ST2082 for 6 Gb and 12 Gb transport, and they have already been published. We’re working on other standards, moving more towards 8K, the whole of UHD-TV present and future. So currently, with regular TV moving on to high dynamic range and high frame rate, and moving on to 8K, it is all being handled—within SDI anyway—through SMPTE.

John: In fact, to date, the UHD-SDI standards are the only published real-time interface for UHD formats. The only way you can guarantee interoperability for transporting UHD around is by using those standards. It is changing, but that is the situation as it stands today.

BEE: There is this impression in the industry that we’re going down a familiar path where we have vendors coming out with their own standards. Is that a danger to this industry? Do we risk anything by going down that path?

Randy: It’s interesting, as you see these other methods for moving [video]-over-IP and at the same time, mezzanine formats for UHD emerging to fit the 12 Gb bandwidth inside a 10 Gb Ethernet, there is the move to publishing registered disclosure documents to assist with the interoperability. What that means from a systems design is you end up with gateways between the two different ways of doing it. There are more and more technology partnerships between vendors; this is something I’m seeing more and more of, which I haven’t seen in the past. So you can “blend” maybe something that’s an RDD, that’s something that’s a standard with something that’s maybe proprietary. The key is that the standards are considered nonproprietary, then you have these proprietary ways of doing things. So long as you have gateways between the proprietary and nonproprietary, you can build out a system. That’s why there’s so much work being done in SMPTE and the VSF [Video Services Forum], to have interoperability across all of the vendors. That’s what we strive for: the interoperability and working with partners who want to interoperate as well.

John Hudson

BEE: Would you characterize that as something that differentiates this transition as opposed to previous implementations of standards?

Randy: It’s interesting because only recently, I’ve kind of become aware of this. You see all these partnerships springing up, for example, intoPix, and the alignment of many with intoPix. You have many in alignment with Sony’s IPLive, you have those in alignment with Evertz’ ASPEN. So what’s happening is you start to see a lot of interplay among the vendors in working together as partners in building out proof-of-concept, getting things working, getting stuff out into the field. There’s a lot of that taking place right now.

John: One of the downsides of the current situation is it does create a bit of confusion for broadcasters who are contemplating new infrastructures, because there’s an awful lot of choice. Any vendors that are part of these alliances can sit down with broadcasters, find out what their requirements are, and can put together a system based on proprietary, standardardized and non-standardized solutions today. What we don’t have at this point—because it’s still very early—is a single, guaranteed interoperable solution that can be offered by many available vendors. But that will come with time. It’s just very early at this point to go full IP and have it completely interoperable.

Nigel: Going back to your earlier question about what was significant about 2022-6, is that it did that for SDI-over-IP. There were several different proprietary ways of doing it and there was a certain amount of take-up. 2022-6 came out and suddenly it’s everywhere. So that’s instructive of just how significant it is when a single standard comes out.

Randy: The interop testing for 2022-6 started earlier in 2015 in the VSF. And just recently, we’re seeing interop between AES-67 and 2022-2. As vendors get together and hook up their equipment and have a plug and play, we’re finding that things are working.

BEE: Would you describe the technology as fully matured, and could a broadcaster or media facility cost effectively implement an IP infrastructure with the technology currently available?

Randy: I would say once a standard is “baked” and is out there and vendors are starting to use it, I suppose you could say it’s “matured” at that point. Are vendors stepping up? Absolutely, there’s no question. And to cost-effectively implement an infrastructure with today’s technology, the answer again is “yes.” To provide some examples, six months or a year ago, for those that said, “I’m going UHD now,” there was a solution that’s fully interoperable, and that was to use quad-link SDI. What we’ve seen emerge in the last six months is the use of mezzanine formats over IP, and now you can build out a hybrid of SDI and IP for HD and UHD together. These are the examples I’m seeing. Those who are considering or who have already gone all quad link, or those who are considering, “well I’ve got an SDI infrastructure now for HD for monitoring, as I bring in my UHD, I have a choice of going all SDI, or I can bring in IP, because I want to be all-IP in the future.” This can be done cost-effectively and products are very, very close to the release point, so over the next six months, you’ll see a lot of activity around systems being built out using this hybrid infrastructure. We’ve been doing proof-of-concepts, and there’s been some business done, but it’s not something I can speak to at this point.

John: From our perspective, we have started to see an awful lot of equipment adopting next-generation UHD-SDI interfaces for 12 Gb for example, and we suspect that we’re going to see a lot of UHD-SDI infrastructure buildout through next year. I think the actual answer is: We will see infrastructures using any and all means: quad-link 3G-SDI, UHD-SDI, IP, mezzanine compression, uncompressed baseband... I think we’re going to see them all. That is, literally the nature of a hybrid infrastructure, which we’re all seeing as the way forward to allow broadcasters to implement UHD systems today that are future-proof for technologies that are coming along in both the IP and SDI domains tomorrow.

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Tom Butts

Tom has covered the broadcast technology market for the past 25 years, including three years handling member communications for the National Association of Broadcasters followed by a year as editor of Video Technology News and DTV Business executive newsletters for Phillips Publishing. In 1999 he launched digitalbroadcasting.com for internet B2B portal Verticalnet. He is also a charter member of the CTA's Academy of Digital TV Pioneers. Since 2001, he has been editor-in-chief of TV Tech (www.tvtech.com), the leading source of news and information on broadcast and related media technology and is a frequent contributor and moderator to the brand’s Tech Leadership events.