Today was the first of a two-day class in Raleigh, NC that I am participating in. Extron electronics invited me (as well as about 40 other consultants) here to attend this training to inform us of their newest product offerings as well as new trends and changes in the world of AV design and integration.
Trying to absorb the information given today for 8 hours was akin to the proverbial "drinking from the fire hose." Even so, I left with a greater understanding of several technologies that I was largely unfamiliar with before. Though the topics ranged from energy star rated amplifiers to twisted pair range extenders, I was most informed and intrigued by the sessions on digital signal transmission and fiber optic transmission.
Though transmitting digital video signals is not cutting edge, the growing use of High-bandwidth Digital Content Protection (HDCP) digital rights management is adding an enormous layer of complication to commercial AV system applications. Consumers are used to seeing this and dealing with it in such applications such as downloaded audio and video files, but the limits that HDCP and its close cousins Advanced Access Content Protection (AACP) and DisplayPort Content Protection (DPCP) enforce create a veritable nightmare for designers and integrators trying to create extensive commercial systems.
To understand the difficulties provided by HDCP, one must have the "keys." HDCP compliant devices use keys to ensure that everything in the signal flow is following the rules set forth under the DRM specifications. Let's look at one example of a Blu-Ray player outputting a signal to a receiver, which in turn outputs to a monitor. All of these components are HDCP compliant. The Blu-Ray disk begins to play, and a key is sent to the receiver. The receiver sends back a message to the player saying that it is compliant with the HDCP specs. It can then send the key on down the line to the monitor, which also sends a confirming message back to the Blu-Ray player. Once this relationship is established, the disk will play as designed. As long as every item in that signal flow is compliant and says so, the viewing experience will not be interrupted.
If however, the rules are broken in any way, the HDCP police will shut down the image. There are several ways for this to happen. One scenario is if one component in the signal flow is not HDCP compliant, like an analog device. This device is not capable of sending and receiving the key information, so it causes an interruption in the flow. For commercial applications, this can potentially cause great difficulty. In general, a Blu-Ray player will have somewhere in the neighborhood of 16 keys that it can distribute. If you have 16 devices in that signal flow, everything is gravy. When you get over 16, one of your devices in the chain will get left out in the cold due to HDCP. Resolving this issue with DRM is one of many to be overcome as content encryption becomes more widespread in the coming years.
Fiber optics is another area that captivated me with the potential. Although a type of fiber optic technology was researched way back in 1877 by John Tyndall, it has only recently begun to be seen as a more feasible transmission method for AV applications. The theoretical capacity of fiber (a mighty 100 Gbs) alone is enough to make it a serious contender for future data transmission. With a possible point-to-point application of about 100 miles, it puts the icing on the cake. Two factors seem to be standing in the way of it rapidly becoming the de facto standard for data transmission. These are cost and complication.
As a few examples of the cost of fiber, the test and installation equipment needed costs tens of thousands of dollars. One example video matrix system that Extron provides can easily near the $750,000 mark. Still as the need for fiber's capabilities approaches, associated costs will inevitably drop.
Today's sessions focused on efficiently and effectively getting the signal where it needs to go, while tomorrow will focus on processing and control of those signals. I'll give a summary of Friday's findings in the evening.
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