Broadcast
The technology to work with IP-based video in live production has been promised for years. We’re now at a tipping point, says Adrian Pennington
It is the most fundamental technical change in broadcasting for decades. Internet Protocol (IP) promises to reduce the ongoing capital spend on equipment at the same time as increasing flexibility to deliver more content to more outlets. The technology is also scaleable to adapt to future audiovisual enhancements in a way that is simply not possible today.
The revolution has been under way for some time in terms of storage, archive, contribution and distribution. Production studios such as ESPN’s Digital Center 2 and Disney/ABC’s global TV operations are entirely built on IP infrastructure.
However, the last link in the chain, live production, is only just coming on stream. With migration to video over IP seen as inevitable, the journey will not be without hiccups.
“Broadcasters know that they have to go down the IP route, but in many cases are unclear as to the best way,” says Tom Swan, sales and marketing director at systems integrator dB Broadcast.
Imagine Communications’ vice-president of strategic solutions management Glodina Connan-Lostanlen is equally cautious. “There’s no denying it will work, but broadcasters have to learn how to design and network a production facility in IP,” she says.
Grass Valley is one of many vendors introducing versions of existing routing, switching and camera hardware with an IP interface. Mark Hilton, vice-president of infrastructure products, believes it is possible to do a small production in IP over a couple of months: “It may not be as elegant as it could be, nor is it a simple plug and play, but you could do it.”
Meanwhile, Quantel Snell head of product marketing Tim Felstead states: “The industry isn’t able to transpose IP into a live environment today.”
SDI, in which digital video is transported serially line by line, frame by frame at a constant rate over copper wire, is being superseded by IP carried over ethernet cable, in which data is chunked into small packets, sent in non-linear fashion and reconfigured at the other end.
The problem with this method in a live environment boils down to timing. SDI has been note-perfect. Engineers can guarantee that video emanating from one source (a camera, for example) will arrive in sync at a particular end point (vision mixer). The same can’t be said of IP.
“It is much more difficult to see what is going on in IP as the control systems don’t exist yet,” says Felstead. “Where SDI routers are very reliable, with straightforward verification of what is happening, IP systems are more opaque. This creates a lack of confidence.”
The risk of on-air black holes or a missing advert will make broadcasters hesitant to invest unless the technology is proven. And since live production is fraught with on-the-fly changes – a late breaking news story with live link via satellite, for instance – it could be the best part of a decade before SDI is consigned to history.
Such conservatism is not unprecedented. The first file-based (XDCAM) camcorders arrived in 2003, but it was not until last year that sales of tape were played out in the European market, according to Futuresource Consulting.
Glastonbury: live IP trial
However, the benefits of IP are compelling and any new studio, facility or outside broadcast truck will have an IP core. Initially, this will be based on SMPTE standard 2022-6, on which most manufacturers’ IPenabled products are based.
A straight reproduction of the SDI standard 2022-6 enables uncompressed realtime video over IP but with no flexibility to switch between audio, video and metadata streams on the same wire – and therefore it does not open up the real potential of IP. SMPTE and other advanced standards that can do this are at least 18 months away.
Matters are more complicated when it comes to 4K UHD. The current standard ethernet connections that interface with equipment like cameras and connect them into the IP network are 10 Gigabit and cannot transport uncompressed 4K. The IP alternative is to compress the data, but the jury is out on exactly which compression route to take.
Contenders include IntoPix’s TICO Alliance, backed by Grass Valley; JPEG2000, on which ESPN’s facility is built; VC2, backed by Quantel; and Sony’s Low Latency Video Codec. London-based V-Nova is another option and claims its codec can deliver 4K picture quality at half current rates (just 78Mbps), with hints that this could be applied to production.
“One of the big wins of IP infrastructure is leveraging the cost savings of commodifi ed IT kit,” says Felstead. “To do that, we need to ensure interoperability, but there is no common standard between enough manufacturers to ensure this.”
Adam Cox, head of broadcast equipment at Futuresource, adds: “The holy grail is to use IT kit off the shelf, but not if there are no standards or if too many standards creates hesitation.”
This concern is repeated time and time again. “4K production will actually slow down developments for IP as the bandwidth requirements would be such that building a reliable IP infrastructure will be very costly and there will be reluctance to invest without a global standard,” says Peter IJkhout, chief technology officer of VidiGo, which is unveiling a live multi-camera cloud-based workflow at IBC next month.
Vendors like Quantel Snell are hedging their bets, incorporating a variety of IP standards into switching and routing gear. “You don’t want to be encoding and decoding at different points in the chain. That is inefficient, risks degrading the signal and, most importantly, it could be uneconomic if the industry needs to licence proprietary codecs,” says Felstead. Sony played a major role in developing the original SDI as a universal interface and is trying to do the same with its own IP connection. It has the support of a number of manufacturers but is unlikely to receive the blessing of rivals such as Panasonic.
“We need standards,” stresses Julian Knight, chief technology officer at integrator and consultant TSL. “Then to build confidence, we need to build islands of IP before we get to end-to-end solutions.”
The move to IP is hugely disruptive: not only does it rip and replace the technical fabric, but it also alters workflows and requires new skills. “If you’ve been working in SDI for 30 years and all of a sudden it’s based on servers, this requires different skill sets,” says Cox. “The lack of skill sets is a big barrier to IP live.”
Broadcasters could choose to upgrade in SDI, for which the roadmap includes a 24G standard capable of 4K at 120 frames a second. However, the IT industry is upping bandwidth at such velocity that technologies of 25GbE, 40GbE and even 100GbE are already emerging, and the cost is reducing every day. Imagine Communications, which is outfitting Disney/ABC with IP, says it has 20 “proofs of concept” in its labs with a 40GbE or 100GbE backbone.
The most attractive argument in favour of IP is that it’s a way to future-proof systems to accommodate 4K UHD, plus any variant that flows from future development like higher dynamic range, higher frame rates, next-generation audio and even 8K UHD. “
IP offers networks without a glass ceiling, so with all these incoming enhancements you can have a clear upgrade path,” says Cox. “The initial outlay may be expensive but it is worth its weight in gold.”
Remote IP Production Solutions
Broadcasters are eyeing IP as a route to cutting costs in live production by controlling all signals, comms and metadata from cameras remotely from a central hub.
The BBC continues to trial IP live. At Glastonbury in June, HD feeds from six stages were transported back to London for web and red button services.
At IBC, Gearhouse Broadcast is demonstrating a remote production workflow by sending HD footage down a 10GbE fibre and cutting the pictures on an EVS IP-enabled switcher.
“Remote production is set to play a fundamental role in the future of our industry and customers are asking us about it,” says Gearhouse head of projects Ed Tischler.
“It’s still very early days, but new technology means we are now in a position to offer a workable solution.”
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