For the last decade and beyond, practically every large AV system that I have encountered has had a matrix switcher at its core. These devices make it possible to efficiently route signals from A to B, providing a level of flexibility in the physical positioning of devices, as well as a level of signal redundancy that would otherwise not be possible.
From Composite video, to Component Video in the analogue era and then on to DVI and HDMI in the digital age, these devices have been extremely useful and valuable to system integrators, and quite a few vendors have built their businesses around switching gear.
As I see it right now, matrix switchers as we know them are about to go extinct. Not matrix switching – that will be around for a long time to come, but the hardware matrix switch is about to be replaced by standard IT network switches.
I believe that this will happen in two forms:
- The Tx/Rx device combined with a standard IT network switch: Basically using an off the shelf network switch to handle the signal switching and using special transmit and receive modules on the source and sink end of the signal chain. Certainly systems with physically distributed inputs and outputs will be likely to follow this route. These types of HDMI infrastructure have been available for a good six months now, and a second generation of these products is due this year.
- The chassis & card based form (as we know it, but with new guts). Basically a new generation of the modular switchers we are used to, but using IP infrastructure instead of dedicated backplanes.
The reason I believe that IP technology is the way forward in this market is that bandwidth requirements for AV signals are increasing faster than AV switch manufacturers are able to keep up. Designing the high bandwidth AV switching backplanes is highly specialised and time consuming, and it a serious serious investment for manufacturers. Product volumes in this industry are relatively small, which means that prices remain high so that manufacturers can earn back their investment.
The IT industry is a different ballgame. With much larger players, selling much higher volumes of product, bandwidth in the IT switching domain comes relatively cheap. It makes a lot of sense then to use readily available IT technology for the AV switching plane, rather than spend big bucks to develop your own. But that has not been possible until recently.
You may be wondering why I’m going on about something that has been around for ages… Video over IP is nothing new, right? Absolutely right, so let me refine my statement.
I need to make a clear distinction between streaming formats and uncompressed, latency free video. Streaming formats have been piped around IT networks for years, but always at the cost of accuracy and always introducing latency. Streaming formats are typically highly compressed in order to reduce bandwidth requirements. The compression reduces quality and requires processing time. On the decoding end, the signal usually gets buffered before it gets rendered, again adding latency. The decoded signal is therefore not a perfect representation of the source signal and is not real-time.
In many applications, these compromises are not a concern. But in high end AV systems (and in more critical applications such as medical and military), native quality signals can be very important, and latency is unwanted or even unacceptable. New technologies are managing to transform HDMI (and other signal formats) into IP packages without lossy compression, pipe them across the network and reproduce a pixel perfect image on the other end, with practically zero latency. Not only that, but they throw in seamless switching, upscaling, downscaling, picture in picture, and video-wall functionality. All in real-time. This is truly an achievement.
The fact that these signals are uncompressed though, mean significant amounts of bandwidth are required. That is where the quickly dropping prices of high bandwidth network switches comes into play. Switches with 10GBit Ethernet ports are quickly approaching the 1GBit pricing level, and 25, 40 and 100GbE switches are all already on the market and also dropping in price as more and more datacenters worldwide start implementing these technologies. Looking at it from that angle, the available bandwidth for IT switches is way ahead of the currently required bandwidth for HDMI, so it’s hard to see HDMI adopters spending a lot more of their R&D budgets developing proprietary backplanes when they can just implement off the shelf technology. A new race has started that will compete for the best Tx and Rx devices with the best feature set for the best price. A very exciting development and there are already some very interesting products to be had.
With InfoComm kicking off tomorrow, I’m keen to see how this trend continues, but I fully expect many manufacturers to announce IP based HDMI switching gear at the show, and I fully expect these technologies to supplant most other offerings within a year or two.
This also means that we are finally seeing a true convergence of AV and IT in the signal domain which is quite a step, and one I’m very excited about. Let’s see where the technology takes us…
Originally published on by Edwin Edelenbos on LinkedIn.