Channel Explosion Turns Broadcast Monitors On Their Head

When most people think of broadcast video monitors, they think of a very expensive, precision television display used to view and judge the quality of broadcast images. Engineers — often nicknamed “Golden Eyes” — assess the TV signal based on years of skill, knowledge and human intuition.

Such video monitors still exist, especially in the network and cinema production environment. However, in a world with an exploding number of broadcast channels, single monitors are no longer adequate in many control rooms to check the quality of broadcast signals.

In today’s studio, single monitors have been largely replaced by a video monitor wall, with displays for program feeds, preview, video servers, cameras, graphics and other sources. In some facilities, the monitor wall is a series of racks containing physical television and computer monitors; in others, it has been replaced with a virtual monitor wall — often called a "glass cockpit." Such walls consist of one or more large video screens, each capable of displaying multiple channel sources in a simulation of a traditional monitor wall.

Because of the large number of video sources in a typical control room, stations are increasingly moving to monitor walls. These display systems are user-configurable and support the display of many video signals, often with overlaid audio and data information.

Such walls are necessary due to a constantly growing number of channels. The “eyeballing” of picture monitors is no longer an adequate method for determining network performance. Today’s multichannel environments process far too much information — whether it be video, surround audio, language options and data services (or combination thereof) — for operators to properly monitor the quality of the signal and integrity of program feeds.

Human observers might be able to pick out video impairments while watching several monitors. However, even if they can find an error among hundreds of channels, identifying the root cause of the impairment is impossible through visual inspection alone.

Along with the technology used to break televisions signals into multiple virtual monitors on walls, another technology is required to detect and automatically alert operators to problems such as bit rate loss, picture artifacts, frozen images, audio mix-ups and missing subtitles. Monitoring also must be available at remote locations, such as in central casting models, and easily interpreted by non-technical staff members whose responsibility covers a myriad of tasks.

Several companies now make products that can detect protocol errors and measure statistics within the MPEG transport stream. Modules are used to measure PID bandwidth, PCR Jitter, T-STD buffer statistics and SI table compliance.

Video quality monitoring can detect freeze frames, momentary picture changes, blockiness, loss of color and overall video quality through the use of an algorithm. Audio is measured for technical defects, as well as human mistakes such as having the wrong language playing on the air. Logs are generated from errors so documentation is available in case of contractual disputes.

Single monitors now used in television facilities may or may not be broadcast quality. Some broadcasters purchase low-cost LED monitors to view the output of a video-generating device, such as playout from a video server, IRD, video camera, VCR or DVD player. They may not be professional quality and simply are used for confidence checking of analog signal and digital signals throughout a system.

The other side of the coin are high-quality single monitors like Sony’s BVME250A 25-inch Trimaster EL OLED master monitor, which is priced at $26,000. OLED (organic light-emitting diode) monitors are now often used for high-end monitoring applications.

The Sony BVME250A Trimaster EL OLED master monitor provides precision and high resolution imaging along with a menu of options including, multiple scan modes, assignable key functions and user LUT ingest.

As well as offering specs superior to CRT monitors, this monitor almost completely eliminates any shading or off axis color shift. These units have accurate black representation and color reproduction, precision imaging without artifacts, stability, consistency and quick response with virtually no motion blur.

Panasonic also has a professional reference 4K monitor for broadcasting and cinema production. The model BT-4LH310, priced at $22,995, is a 31-inch monitor suitable for use both in the studio and on location. 

The Panasonic BT-4LH310 reference monitor supports both 4K (4096 x 2160) and QFHD (3840 x 2160). In addition to meeting the DCI (P3) color gamut standards, the monitor's new LUT upload function supports high-precision color management in a digital cinema workflow.

The Panasonic monitor features a 10-bit, 31-inch LCD panel that is LED backlit. It will accept 4K sources through SDI, HDMI and DisplayPort. In addition to DCI 4K, it will accept QFHD/UHD 4K (3840 x 2160), 2K and high definition video sources along with up to 16 channels of embedded audio.

For studio wall applications, several companies take large LED/LCD panels, add custom I/O and software, creating full configurable displays. For instance, Evertz makes the MVP Multi-Image Display and Monitoring System. The MVP offers a comprehensive approach to virtual wall monitor applications. It can display any input signal to any output monitor and can used without the need for DAs or upstream monitor routers.

The Evertz MVP system can expand in size from 8 inputs with a single output, to as large as 1000+ inputs feeding more than 50 displays.

The system also integrates monitoring functions into the video wall. Its signal monitoring includes loss of video, active picture levels, EDH errors, frozen or black video, motion detection, video format detection, loss of audio channels, mono audio detection, phase reversal, audio too loud or too quiet, loss of closed captioning, loss of closed cap waveform, loss of program rating, source ID missing and VITC missing.

Other companies making video wall components include Wohler, Orad, Vizrt, VisionFrame, CubeX Video, Marshall Electronics, Planar, Samsung, Vista Systems, Zandar Technologies, Mitsubishi, Barco, Prysm, eyevis, NEC, LG, NanoLumens, Orion, MediaGrid, SiliconCore, EMS, Grass Valley and Imagine Communications.

Control technology for video walls is available from a variety of sources including; Vista Systems, Ross VideoMatrox GraphicsBlackmagic Design, TV One, Gefen, Christie, Seneca, VideoPlex and others.

Remote production trucks can require dozens of video source monitors. Increasingly what used to be a mass of individual monitors is being replaced by several large monitor panels, which can display many sources and yet be quickly reconfigured to a virtually any layout.

NEP, one of the world’s largest studio and remote truck companies, has even launched its own software called The Wall. It’s an app for the Apple iPad that enables quick pre-configuration of complex monitor walls in mobile production units. Monitors need to be reconfigured for each show, often with only hours from the time the mobile unit parks until it goes on-the-air live.

NEP has developed an Apple iPad app that enables the quick reconfiguration of multiple monitor panels. A task which used to take hours can now be done in minutes.

This app allows engineers, technicians and members of a production team to set up their own monitor walls and make changes on the fly whenever they want without having to wait for the mobile unit engineer to go through a long configuration process. Because trucks may have more than 150 individual monitors displaying as many as 32 video sources each, this app can be a huge time saver.

“Compared to our previous manual processes, The Wall was like going from a rotary dial phone to an iPhone 5 overnight,” said Kris Castro, a beta user and technical director for a major sports broadcaster. “A configuration that used to take at least three hours now takes maybe 15 minutes.

“In addition to being a tremendous time-saver, The Wall has given me much more flexibility. Without having to involve an engineer, I can log in to the system and make necessary changes, or configure the monitor wall offline and then save the configurations under my name. If I want to use a configuration from last week, it’s there and ready to load. And if I want to create a layout for a director I’m working with in three weeks, I can do it in advance and then just walk right onto the truck and patch the monitors in a matter of minutes. NEP has created an incredibly smart way of approaching this task.”

Software-based diagnostics and virtual channels on single large LED wall displays have fundamentally changed monitor technology in the studio. However, on original productions for television or cinema, a single high-quality monitor with a pair of “golden eyes” to check quality remains as essential as ever.

Comments:

Very interesting article from Frank. We too have recognised the trend toward large screens and multi-viewer systems and address this from ‘both ends’ in order to provide broadcasters with optimal solutions.  Firstly, it can often be lower cost to have dedicated picture monitors rather than using a multi-viewer however as there is a cross over point at around 64 signals and above, where large multi-viewers can be more cost effective.  The monitor manufacturers refereed to in Franks article generally produce premium price monitors and have a very limited range of models which are not designed for large scale monitor walls. Recognising the trend in monitor walls we specifically designed a range of low cost, fit for purpose picture monitors with broadcast colourimetry and backlight levels, for use in galleries and monitor walls. For example, a stack with 64 x 9.7” monitors cost less than a 64 input, 4 output multi-viewer system and 4 x 42” screens. Having dedicated source monitors provides better redundancy and system resilience . Secondly, the picture quality from 9.7” monitors is far greater (1024x768 resolution) than say a 16th of a 42” monitor, which equates to a resolution of 480x270.  So, in this example a dedicated single source monitor solution is not only more cost effective but gives better picture quality and improves reliability. For walls from 64 to 96 inputs, using 16 x 21.5” with quad multi-viewers can be most cost effective and has reliance in its favour.  Frank makes a good point about how much human eyes can take in and with more than 64 signals it is often beneficial to have automatic signal deficiency and loss detection for both audio and video and hence why, in this example, we suggest using quad multi-viewers. With 21.5” monitors the effective resolution per quadrant is 960x540 and significantly better than 480x270 you’d get on a 42” monitor showing 16 signals.

Finally, there is a further consideration to this scenario and that is space which can be limited in trucks. Using a mini monitor bridge such as the Eve-HD which has 5 x 2.8” (480x270 resolution) monitors in a 2RU strip you can monitor 40 signals, for example, in two banks of 8RU and use standard 19” racks to keep costs down. This approach reduces the cost to roughly half in comparison to using a 48x4 multi-viewer and 4 x 42” monitors. 

In summary, dedicated single monitor picture monitoring can be more cost effective than using multi-viewers in systems up to 64 signals and above this size multi-viewers begin to offer greater affordability.Our philosophy is to offer a choice of solutions to our customers and having both monitors and multi-viewers in our portfolio allows us to ensure that our customer have the full picture and receive optimal solutions.

October 22nd 2014 @ 19:08 by steve hathaway

With regards to NEPs software in Franks article, called The Wall, there is in fact ‘off the shelf’ software available. As we specialize in video monitoring we work with a wide variety of broadcast companies, always focussed on providing the optimum solutions. We have three versions of control and configuration software, each of which runs on a PC, allowing you to ‘drag and drop’ screens onto a virtual monitor wall and then apply specific set-ups to each screen.  By clicking on an individual screen you can take control of the device and adjust it’s parameters. With our more advanced systems you can control all monitors on a network which, for an OB, could include main gallery, VT, sound, engineering and racking and hence you can have different set-ups for different areas, with for example, audio meters and UMDs on the source monitors but not on the programme and preview monitors or say, loudness on the engineering monitors only or safe area markers in graphics.   

What’s more, and very importantly, the monitor control software allows you to manage colour and backlight. For example, some directors like higher brightness pictures and therefore, at the touch of a mouse you could adjust the brightness of all the monitors in the gallery. Once the appropriate backlight level is set this can be saved as a pre-set and recalled the next time the same director uses the truck. Whilst LCD technology remains the most accurate and affordable display technology for broadcast, some companies like to use OLED monitors. It is not possible to get a OLED to look like a LCD but you can often adjust a LCD to have a similar look and feel to a OLED and therefore the colour management of the monitors is a very useful tool be able to adjust monitors to specific production requirements.

In summary, the network control software allows users to configure and control monitors, individually or as groups across a network. Different set-ups can be saved and recalled and the software will interface to larger control systems. It is available on simple $900 monitors through to reference standard monitors and most often included free of charge with the monitors and therefore very affordable!

October 23rd 2014 @ 10:29 by steve hathaway

Steve:

Your comments are excellent. I should note that my article was about monitors for viewing in broadcast control rooms, trucks and locations for critical evaluation viewing. Many of these models have video quality control monitoring built-in for operators who must view the output of many channels at once. So these are not just monitors, but also devices that feature sophisticated algorithms for quality and missing information.

There are dozens of monitor options for these types of installations and I only mentioned the most prominent brands.

The monitors I discuss in the article should not be confused with monitor walls for studios as part of on-air sets or for commercial display installations. Certainly for these types of monitors the same critical level is not required.

Some LED lighting designers have told me that sometimes these on-air studio monitors have to be adjusted not to look good to the naked eye in order to look great on the air.

Just as with many broadcast products, prices vary according to quality needs in a given installation. It’s the same with monitors.

Frank Beacham

October 23rd 2014 @ 17:04 by Richard Woolley Editor
Let us know what you think…

Log-in or Register for free to post comments…

You might also like...

Essential Guide:  IP - The Final Frontier

Today’s broadcast engineers face a unique challenge, one that is likely unfamiliar to these professionals. The challenge is to design, build and operate IP-centric solutions for video and audio content.

Cost-effective IP Contribution and Distribution

Saving dollars is one of the reasons broadcasters are moving to IP. Network speeds have now reached a level where real-time video and audio distribution is a realistic option. Taking this technology to another level, Rohde and Schwarz demonstrate in…

IMF - Interoperability and Content Exchange Made Easy

As the television business has become more global, and evolving consumer devices spawn the need for ever more formats, there has been an explosion of the number of versions that are needed for an item of content. The need to…

Sony Virtual Production Service Launched at Red Bull Event

Although OTT delivery has created a mature market for on-demand scripted shows that leverages the public internet for distribution, the ever increasing and IP-enabled bandwidth available that uses public wireless networks and the public cloud, is opening a new market…

NEP Sweden Rolls Out XT4K Servers In New UHD-1 HDR OB Truck For 2018 IIHF Championship

NEP Sweden, a division of NEP Europe, has selected EVS XT4K ChannelMAX servers to drive the ingest, playout, slow motion replay and highlights production within its new UHD-1 OB truck. The mobile production unit was used for the first…