MEDIA MANIPULATION
In a strange kind of way, the pro-AV market is just starting to catch up with trends that had their genesis in the domestic market. It’s all systems go, reports Derek Powell.
The pro-AV market is taking lessons from consumer AV for once, says Derek Powell.
We have looked at a few crossovers between the corporate AV market and consumer sound and image products lately, and it continues to be a fascinating comparison. The latest thing to hit the enterprise end of the pro AV market is the ‘fully converged network’. This essentially means two quite separate things.
Firstly, in an installation that follows the principles of a fully converged network, there is very little dedicated AV wiring connecting the various pieces of equipment. In a typical meeting room or teaching space you’ll still find speaker cables and the occasional short run of HDMI cable, but extensive runs of HDBaseT (for transporting video) or RS-232 (for control signals) are rapidly disappearing. Instead, monitors, amplifiers and all the other input and output devices now connect either directly or via a decoder to the standard data network. That’s the same network that connects all the usual IT devices like servers, PCs, printers and disk storage. Frankly, that part is not so much of a surprise. Last year we looked at the steady progression of content migrating to Ethernet transport (see ‘Blue Planet’ in Volume 29 number 3).
It’s the second part of the ‘fully converged network’ that’s unexpected. Various ‘black boxes’ like DSPs, matrix switchers and automation controllers — equipment we’d normally expect find racked up in each classroom or meeting room — are rapidly disappearing! And it’s happening because much of the processing involved is now carried out remotely. The video routing and distribution systems, the Digital Signal Processors (DSPs) that handle the sound, the control processors that tie everything together — these are now located in a data centre, rather than in the rooms where the users are located.
Much of the equipment that’s actually in a room (monitors, microphones, active speakers and so on) is simply plugged into a convenient network socket — and power, if needed, though plenty of devices now work on Power over Ethernet (POE). There’s no need to plug a microphone into a physical mixer in the room. To set the system up you simply plug the mike into an interface box and allocate an address (an IP number) on the network. Then you program that IP number into a DSP somewhere, and tell it how you want the microphone amplified, equalised and compressed, and where to send that signal. The DSP will process the sound in a heartbeat and instantly send it back, maybe to a speaker in that room, a video-conferencing system, or both. The trick is that most DSPs now have enough processing power to handle hundreds of audio sources at the same time — and to keep them all separate. There’s no need to buy a new mixer when you add an extra meeting room — just route any new microphones over the network to an existing DSP and it will happily deal with that microphone along with scores of other audio signals that it is already processing for dozens of other rooms.
While this ‘converged network’ model with its centralised AV resources doesn’t add up financially for very simple installations or just a few rooms, it is hitting the market that
Domestic ‘assistants’ are currently marketed on their ability to respond by voice to various questions and requests for entertainment. But make no mistake, they are also positioning to control your lighting and appliances.”
deals with universities and corporate buildings like a thunderbolt right now. The thing is, no one should be surprised, because the precursors to this kind of thinking have been with us for some time — in the domestic scene.
Domestic help
Not so long ago, we were used to handling analogue YUV video signals using 75-ohm coaxial cable and plugging together players and projectors through BNC connectors. We’d connect up the audio to the AV receiver with speakers set up ‘just so’ around our dedicated media room. Then we’d pop in a DVD (or, sigh, a VHS tape) from our collection and settle back.
Now, it’s different. Domestic users are embracing media — whether video or music — that arrives as a digital stream either from the cloud (Netflix, Spotify) or from your phone or home server via Wi-Fi. And it increasingly appears in every room, thanks to the popularity of any one of a dozen brands of distributed audio systems, or simply by merit of a portable digital source (aka your phone). When media is encoded as a stream, it can pass across almost any kind of data network, whether that be wired, Wi-Fi or even the internet. Enabling the trend, the last few years have seen bandwidth boosted with better broadband access (for some, so far), more efficient codecs (like MPEG-4) and gigabitcapable home routers that are less likely to choke on high resolution media.
This has meant that there is no need to run audio or video cables through your walls to get entertainment in every room. It is easy to use the data network (or Wi-Fi) that you already have in place.
That trend has taken off in the corporate market as well. Corporate AV purchasers these days tend to be from the IT department, and they see the advantages of using a single network for all kinds of business content. Manufacturers, leveraging the lessons learned in the consumer and broadcast markets, are figuring out how to use sophisticated MPEG and M-JPEG encoders to packetise every kind of input and shoot it across the network to monitors, projectors or speakers anywhere in the building — or beyond.
At the same time (at least in the US) we’ve seen the growth sector in home automation systems shift from the proprietary hardwired systems like Crestron and AMX to the wireless plug’n’play ‘assistants’ such as Google Home, Amazon Echo and Apple’s Home Pod.
These domestic ‘assistants’ are currently marketed on their ability to respond by voice to various questions and requests for entertainment. But make no mistake, they are also positioning to control your household lighting and appliances as well.
The key here is the ubiquitous Internet of Things (the IoT). It used to be difficult to control devices which might require different interfaces — relays, infra-red, RS-232 and so on. But now everything from your AV receiver to your refrigerator has a network connection, making control via the network (wired or Wi-Fi) a snap. The common thread to these assistants (apart from voice interaction) is that most of the intelligence required is actually based remotely, with servers located in the cloud.
Having access to information and processing power stored on the internet gives domestic assistants enormous advantages in device control. For ‘traditional’ control systems to take command of a TV, or an AV receiver — or an air conditioner — a technician would have to come and wire in a direct connection and program the controller with the specific codes for each device to turn it on, or change input, or whatever. With an intelligent network-connected controller you can simply say “change the TV channel” and the assistant can do the rest. It will contact the device to read out its model number, then consult an online database to determine the correct code for ‘channel up’ on that set before issuing the command over the network. If you buy a new TV, the process is the same — so no re-programming required.
With a few modifications, that’s pretty much the way pro AV control systems are now headed. If a user in a meeting room wants to say, turn on the AV system, they now make that request by logging in to a web page. That might be from a dedicated control screen on the wall, but they might choose to use any browser on their phone, tablet PC — or in future a voice assistant. A remote server detects where the user is, looks up the commands to power up the equipment in the room, and issues those over the network to the equipment. All systems go.
It’s a seismic shift in the way pro audiovisual installations are designed, installed and maintained, because it’s all about shifting data, not dealing separately with sound, images and control signals.
So, take a bow (or perhaps take the blame) if you have adopted a network-centric approach to home entertainment. You are pushing change on a bigger scale than you probably realised!