Multiviewers For Flexible Operations - Part 2
IP is delivering new opportunities in terms of distributed processing and de-centralization. In the second part in this series, we look at the practicalities of using COTS hardware and the advantages it has for multiviewer monitoring over traditional SDI hardware solutions.
De-centralization Benefits
This leads to the concept of distributed processing. We no longer have to store all our hardware in one specific room or datacenter as it can be easily situated in other rooms, buildings, cities or even countries. The processing power stays where the data flow is most concentrated to keep network connections optimized and as low as possible.
Sports events vary enormously in their technical requirements. For example, a football match may need cameras and sound from one location and a hockey match from another. Routing the camera sources to the multiviewer, configuring the position on the display and then adding captions can be logistically very difficult.
Traditionally, we would have used SDI routing matrices to provide the correct sources to the multiviewer and this in itself would have been a difficult and challenging task. Fraught with the potential for error, changing multiviewer configurations was never that easy.
Multicasting Gains
Media IP systems, especially those using ST2110, will use IP multicasting to distribute video and audio. This is the IP equivalent of the video and audio distribution amplifiers and allows single directional flows with a one-to- many mapping when distributing video and audio through a network. This work is massively to our advantage as the receiving device (in this case the multiviewer) actively requests the multicast stream from the network switch it’s connected to.
The combined automation of signal routing and display configuration can be easily managed allowing an entire configuration, including its sources, to be adapted within a matter of minutes. This automation takes the concept of flexibility to new levels as a studio can be configured for different events with incredible speed.
Again, it’s important to remember that the multiviewer is now abstracted away from the hardware as it is a software application. It’s fair to say the software will be highly tuned to make the best use of the servers’ hardware resources, but it does not rely on custom circuits such as SDI cards to make it work. The video, audio and metadata are going in and out of the server via the Ethernet connection. It’s only when the data arrives at the display is it converted to HDMI for viewing.
IP Distance Flexibility
This leads to another interesting concept and that is that the multiviewer no longer has to be physically close to the flat panel display. In SDI infrastructures, the multiviewer, being a custom hardware device, was limited to its proximity to the display. SDI cable has a maximum distance with which it can reliably transfer a signal thus restricting the distance to the displays. We could use distribution amplifiers or fiber converters to increase the effective length of transmission, but this is messy, increases complexity and introduces unnecessary points of failure.
IP is transport stream agnostic and so we can transfer it over many different types of standard IT infrastructure. The HDMI connection does have a physical limitation for distance, but the IP converters can be easily mounted on the rear of the flat panel displays and the Ethernet run to it either as twisted pair CAT6/7/8 or fiber.
Figure 1 – security should be built into an infrastructure at the beginning of a design and not be an after-thought at the end. Here, the servers “chain of trust” starts at the base of the server with the hardware security as each component must not only be compatible with the server hardware but also have verified provenance, the “secure boot code” confirms the hardware layer is verified and then “integrity checking” verifies the firmware installed on components such as the disc drives and video cards, “validating system images” verifies the kernels and drivers have not been tampered with and “authorized applications” confirms the applications running on the server are from trusted parties.
Abstracting the multiviewer application in this way further presents us with more opportunities to decentralize our infrastructure or completely move the processing off site to the cloud, especially when we consider the flexibility software licensing offers.
Although software licensing is well established in IT used in other industries, it has only recently gained attention within broadcasting. The ability to distribute code safely and securely with flexible usage benefits both the vendor and broadcaster massively. A license is a unique code that can be locked to a specific release of code to allow vendors to enable specific functions within an application for a specified length of time.
OPEX Functionality
This is further enforcing the idea of the OPEX model. Instead of thinking about buying products that provide a specific service, we should now be thinking in terms of a group of functional requirements that meet the needs of a production.
OPEX is incredibly popular as it allows business owners to scale their infrastructure costs at a rate proportional to their sales as upfront costs are greatly minimized. This can be further improved if the broadcaster opts for a full cloud model. But even if they don’t and they do opt for a combined CAPEX/OPEX model, then the amount of hardware, such as servers and network devices, will also be greatly minimized as they will only need to be procured as the business expands.
Service Level Agreements are a well-established model and will give broadcasters even more flexibility for support. Many IT vendors have been providing this model for years and can offer many different services from same day repair to guaranteed delivery of new components within a few days. This reduces the need for a broadcaster to hold spares and reduces all the associated costs that go with it.
Licensing Resilience
Software licensing and functional thinking now opens up a whole new world of flexibility. Instead of buying multiviewers for a studio control room to meet peak demand, the broadcaster may find that they only need two multiviewers for 80% of the time. The licenses for the additional two multiviewers can be purchased as required. As the software license is effectively a file, it can be downloaded from the vendors website so there are no shipping costs or delays.
In this scenario, the broadcaster may have opted to build a server farm where the servers can be allocated to functions as required, such as a multiviewer. The software can be pre-installed and then just enabled by the software license. This is the ultimate in flexibility as the software is not even tied to a specific server and can be run from any of the servers in the server pool.
Cyber security is gaining more interest, especially as broadcasters move more to IP. Modern IT COTS servers have security built into them at a hardware level and to truly take advantage of the protection they provide then they must be kept up to date with software and firmware patches. This is another reason to buy SLAs, and while security at this level is also provided by cloud operators in the end security is always the responsibility of the broadcaster.
Greater Scope
Software applications provide more scope for security than we’ve ever had with traditional broadcast equipment.
We can provide much more granular access to the functionality of the code. For example, with the multiviewer only an engineer can change the configuration, but a studio camera operator can change the mnemonic for each part of the display.
Another consequence of software licensing and the flexibility it offers is that we are making the systems future proof. Even taking Moore’s law into consideration, the processing power available to us will only increase over the years. More industry’s outside of broadcasting are driving the need to improve the resources available and it is this innovation that we ride on and improve how we design, build and operate broadcast infrastructures.
Multiviewer flexibility has improved immeasurably in recent years. Not only has the product’s feature-set improved but the combination of software licensing and COTS infrastructures has helped deliver unparalleled flexibility.
Supported by
Broadcast Bridge Survey
You might also like...
Designing IP Broadcast Systems - The Book
Designing IP Broadcast Systems is another massive body of research driven work - with over 27,000 words in 18 articles, in a free 84 page eBook. It provides extensive insight into the technology and engineering methodology required to create practical IP based broadcast…
Demands On Production With HDR & WCG
The adoption of HDR requires adjustments in workflow that place different requirements on both people and technology, especially when multiple formats are required simultaneously.
NDI For Broadcast: Part 3 – Bridging The Gap
This third and for now, final part of our mini-series exploring NDI and its place in broadcast infrastructure moves on to a trio of tools released with NDI 5.0 which are all aimed at facilitating remote and collaborative workflows; NDI Audio,…
Designing An LED Wall Display For Virtual Production - Part 2
We conclude our discussion of how the LED wall is far more than just a backdrop for the actors on a virtual production stage - it must be calibrated to work in harmony with camera, tracking and lighting systems in…
Microphones: Part 2 - Design Principles
Successful microphones have been built working on a number of different principles. Those ideas will be looked at here.