Multiviewers: Keeping an Eye on Things

Evertz
Evertz multiviewer systems installed at the master control and playout areas at the WarnerMedia–Turner Broadcasting Techwood Campus in Atlanta (Image credit: Evertz)

LONDON—The screen has and always will be both the symbol of television and the means of watching it, however on both the viewing and production sides, displaying TV pictures has changed considerably in the last 20 years, when CRTs reigned supreme. While the consumer market has diversified into smaller screens on mobile devices, broadcast operations have evolved rapidly thanks to the multiviewer.

This technology has made a discernable difference to studio galleries, OB trucks and playout centers, not only in terms of layout—with only a few screens replacing banks of older style monitors—but also in how operations are carried out. More sources can be displayed in a gallery or OB vehicle and more outputs can be monitored in master control rooms (MCRs) by only a few operators. 

As John Mailhot, chief technology officer for networking products at Imagine Communication notes, multiviewers are now “the design standard” for facilities, with the previously ubiquitous walls of discreet monitors nowhere to be seen.

CUSTOMIZING THE WORKFLOW

“Equipping a facility is now more cost-effective with multiviewers,” Mailhot says. “But requirements are different in different parts of the workflow. You’ve got replay, playback and then camera shading, which might have multiviewers to keep an eye on everything and then one or two ‘real’ monitors for fine-tuning. The need is to make sure that each professional involved in the production can see what they need to see, because the more sources there are, the more the need to get in front of them.”

 John Mailhot, CTO, Imagine Communications.  (Image credit: Imagine Communications)

In the past, monitors displayed pictures while other functions were carried out around them. But as Martin Jolicoeur, strategic product manager for Grass Valley notes, “It is becoming harder to talk about the multiviewer by itself.” This, he explains, is nothing new and started to happen when multiviewers first appeared.

“Both at the user level and the product level, the expectation is for more than just seeing images,” he said. “[Multiviewers] are working in conjunction with tallies and [other] tools. In the past multiviewers worked with switchers or routers and this is something that is not changing as we make the move to cloud and software-based technologies.”

As part of this, GV has a multiviewer component in its AMPP (Agile Media Processing Platform), a SaaS (Software as a Service) system that provides cloud connectivity for a range of broadcast applications. Jolicoeur says this was accelerated by the need for desktop-based multiviewing, which grew substantially during the Covid-19 pandemic. This allows remote access to the multiviewing system in MCRs, where GV’s Kaleido-IP is used for on-premises operations (as well as in studio galleries and OB trucks).

  Suzana Brady, senior vice president of worldwide sales and marketing at Cobalt Digital. (Image credit: Cobalt Digital)

Suzana Brady, senior vice president of worldwide sales and marketing at Cobalt Digital, comments that remote control is a must for off-premises operation of multiviewer systems.

“It’s also crucial to have the ability to bring back the multiviewer output to a remote operator,” she says, “so a multiviewer at the station or studio is combined with a streaming encoder to provide a low latency feed over the internet that can be accepted by a computer, phone or tablet. We are additionally seeing a trend towards software-based multiviewers for streaming but they are typically not as feature-rich as hardware units.”

THE UBIQUITY OF IP

IP is increasingly the norm for both on-prem and remote working, covering all forms of equipment but increasingly multiviewers. An illustration of this is the recent installation at Red Bee Media’s U.K. facilities in London and Salford. The previous SDI-based monitoring infrastructure has been replaced by an IP multiviewer network based on the Rohde & Schwarz Prismon system. 

This was possible, says Andreas Loges, vice president of media technologies at R&S, because of the technology’s “software-defined approach,” which allows for a hybrid platform supporting SDI and IP signals, in both SMPTE ST 2022-6 and ST 2110.

Lawo, a leading proponent of IP now produces a multiviewer alongside its audio console and video processing/networking products. Stephan Türkay, senior product manager for media infrastructure, comments that the pandemic has pushed the adoption of IP even further, with the format now defining trends in multiviewers.

 Stephan Türkay, senior product manager for media infrastructure, Lawo. (Image credit: Lawo)

“IP technology delivers on flexibility, scalability and being totally agnostic, [making it] inherently compatible with any requested broadcast format and connecting endpoints no matter how far they are apart physically,” he says. “Native IP multiviewers have practically become state-of-the-art technology, with software-defined processing and distributed architectures. They fully embrace the benefits of IP technology and allow for a leap in dynamic management of processing resources and practically unlimited scaling.”

Today’s leading multiviewers are designed to monitor SMPTE ST 2022-6 and ST 2110 video streams, which have standardized signals and distribution for broadcasting. They are also, as Ketan Patel, product manager of multiviewer solutions at Evertz, observes, also going beyond their original display role. 

“Multiviewers remain a tool for visualized video, audio and ancillary data analysis,” he says, “but as broadcast continues to evolve, the need for more advanced and specialized monitoring features continues to grow. Some of these new requirements include monitoring for regionalized freeze and black detection, lip-sync monitoring, loudness monitoring and more.”

Multiviewers are now established in MCRs at broadcast centers and playout facilities, which handle multiple channels of both linear TV and OTT services. The trend is for fewer operators at the MCRs, with compliance monitoring software used to display images only when a problem is detected. Known as "monitoring by exception," this technique is used increasingly on the distribution side, with multiviewers working in conjunction with specialist software.

Compliance system developer Mediaproxy produces its own multiviewer, the Monwall. CEO Erik Otto explains that the Monwall was developed on the basis of the emerging trend for software-based interactive displays, with the aim of allowing live streams of both broadcast and OTT sources to be displayed and monitored.

“It works in conjunction with our LogServer monitoring platform to display any faults,” he says. “Because of the large number of outputs that need to be monitored in today’s multichannel world, it is no longer practical for MCR operators to view each channel on individual screens. Monitoring by exception is becoming the norm, with penalty boxes on multiviewers only activated when a fault is detected. This is a much more efficient way of monitoring and also uses the operators’ time and expertise more effectively.”

Broadcasting has broadened in scope over the last decade, with streaming running in parallel with linear transmission. This has called for new techniques and technologies, something illustrated by the development of the multiviewer. That evolution looks set to continue as broadcasters and OTT platforms look for new forms of content and revenue, including eSports production.

“The rapid development of complex, multi-layered production environments is challenging vendors to adapt and respond with agile, scalable and cost-efficient technologies that fit the needs of this type of production,” says Kevin Joyce, Zer0 Friction Officer at TAG Video Systems. “On the multiviewer and monitoring side, most gaming productions require the ability to work in the cloud, customizable interfaces for dispersed workforces and, of course, the ability to monitor signals from production to delivery and ensure the highest level of quality for maximum engagement.”

Issues like this are among a growing number of technological challenges the now not-so-humble multiviewer faces in the near future. As Mailhot at Imagine concludes, there is a “plethora” of video formats to deal with and that only continues to grow.

“We are seeing the beginnings of HDR, which will blossom in the next five years,” he says. “Related to that is the scaling up of UHD, which will pose a design challenge for multiviewers because it’s four times as much data and we can’t take the HD approach and just make [the displays] bigger.”

With all this happening, multiviewers are certainly something to watch.