AV Technology - February/March 2009 - (Page 44) MULTI-TASKING WITH TECHNOLOGY capture content from multiple sources and arrange it as needed on a display wall. A subset, multiviewers, permit the assembled multi-image display to be routed as configured to multiple locations. “Depending on the size of a center, the processor is the most critical and complex part — and the most expensive,” says Mike Pratt, vice president of technical services for Hoffman Video Systems, a Glendale, CAbased integrator with command/control center expertise. “Taking 200 or more inputs and mixing and matching them for display in the correct resolution can require a processor costing anywhere from $150,000 to $1 million.” New generations of processors are giving centers more content display options. Avitech International Group of Redmond, WA, has developed proprietary techniques to combine multiple high-resolution computer images and high-definition video signals. According to company president Morris Gong, “The biggest growth area for command/control centers is an increasing number of computer images and the addition of HD-SDI signals to the mix.” But combining these image types can be tricky. “A scaling algorithm applicable to video may not be as useful for a still image,” says Gong. “For video, temporal values are equally as critical as the spatial ones.” With demand for video on display walls growing, Jupiter Systems, Hayward, CA, has unveiled PixelNet, a packet switching-based solution for distributing high-resolution, real-time video in command/control centers. Conceived as an adjunct to Jupiter’s Fusion processor, it’s now offered as a standalone. It uses a switch-connected node configuration to deliver a high degree of flexibility for selecting and routing sources, as well as how they’re displayed. “Video distribution can grow, shrink and change as needed much more easily,” says John Stark, director of product management. EFFECTIVE SYSTEMS Whether functioning as part of a video wall or a standalone, a projection cube, LCD, or plasma display must be capable of delivering images that can be easily seen in environments where variables like ambient lighting, sight lines, and user eye strain come into play. Key control factors are brightness, contrast, resolution, intensity, color reproduction, and calibration. (See sidebar, “Display Considerations.”) “Display calibration — getting images to match up as perfectly as possibly — is especially important in a multi-display environment,” says Pratt. “We do signal impedance tests that ensure images line up to the naked eye and we also use edge blending technologies.” While processor and display technology allows ever larger and “busier” videowalls, designers should employ HFE to guard against overloading operator circuits. But the threshold can be fairly high, says Chris Thomasen, a designer with Audio Visual Technologies Group, Stafford, TX. “Some clients want up to 12 images on a screen,” he says. “When you’re confronted with that many on one screen and there’s maybe eight screens in play, all going at the same time, your first thought is, ‘Wow, how can I take that in?’ But it’s like driving a car. You learn how to use it.” Advanced control systems that are highly intuitive, from suppliers like AMX and Crestron, can go a long ways toward improving functionality, Thomasen says. As a leader in infrared wireless microphones, AZDEN offers years of experience in creating systems for conference and classrooms that work in real-word situations. NO RF INTERFERENCE In today’s RF-saturated world, Azden’s infrared offers protection from RF interference from other devices, including DTV, cell phones and other electronic gear. SAFE AND SECURE Azden infrared offers the built-in advantage of absolute security from eavesdropping or monitoring. What is said in the room, stays in the room. AZDEN INFRARED CONFERENCING Our 6-channel infrared system features a rack-mount receiver (1RR-106) with 6 individual (volume adjustable) outputs and one “mixer output.” It also has 4 external sensor inputs, to give better coverage for “difficult” rooms. The Chairman’s mic (IRC-51) can override the other mics (IRC-55) and each mic has an LED ring which lights when in use. Azden tabletop mics can use Alkaline or rechargeable batteries, which provide power, and can be recharged while in the mic, from a wall-mount charger. Azden also offers single and dual channel infrared systems. Details are available at our website: www.azdencorp.com 44 | AV TECHNOLOGY | february | march 2009 http://www.azdencorp.com http://www.azdencorp.com
For optimal viewing of this digital publication, please enable JavaScript and then refresh the page. If you would like to try to load the digital publication without using Flash Player detection, please click here.