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  Videoconferencing: A Desktop With A View By Dave Brown The desktop videoconferencing (DVC) market is fulminating. This year will be one of explosion in standards adoption, network evolution and platform improvements. At the start of this decade, "videoconferencing" primarily meant ISDN-connected group systems starting at $35,000. Today, shakeouts, acquisitions and competitive jockeying have cleared the room/group systems playing field to the "big two"--PictureTel Corp. and VTEL Corp. Desktop program sales are driving group system sales. Intel Co rp., PictureTel and VTEL are playing major roles in defining the market. Theirs and other manufacturers' add-on products will allow the set-up of PC-based stations that play well with other workstations or group systems. The cost of these systems ranges from $2,000 to $7,000. Jim Herbert, executive director of the International Tel econferencing Association (ITCA, www.itca.org) estimates that 50 million conferencing-ready PCs will be in circulation by year's end. "1997 will be the year demand for videoconferencing applications begins to build in the workplace," he says. Herbert quotes Infonetics Research to predict that "59 percent of companies surveyed are planning to run videoconferencing over LANs by year's end." These companies want transmission options other than ISDN for wide area networking and telecommuting. Power Shift This network evolution is being driven by the microcomputer revolution. Costs continue to drop; multimedia features and video capabilities within basic PCs are dramat ically improving so that add-on boards are needed less and less. Slightly more than a year ago, our March 15, 1996, Buyer's Guide, "Videoconferencing: The Better to See You With" (techweb. cmp.com/nc/704/704buyers.html), covered mostly room systems and a few early entries in the desktop market. With these, compression was performed by specially designed auxiliary coder-decoder (codec) hardware. Encoding audio and video into a narrow data bitstream is an intense computational process that would overwhelm an Intel 386-class PC, but it can be accomplished marginally well by a Pentium operating at 90 MHz. Increase the speed of that processor, add some additional memory and Intel's MMX set of 57 new instructions that optimize multimedia operations, and you have a workstation that may be able to support video without expensive add-on codecs. This year's greatly expanded Buyer's Guide, beginning on page 126, illustrates the current DVC spectrum. You'll notice that add-on board sets costing thousands of dolla rs usually need only an i386 processor to run the supporting application software and communications management. PictureTel's Live 50 and VTEL's Personal Collaborator handle all audio and video processing on a plug-in codec board--and include camera, microphone and speakers for $2,495. They provide excellent audio and a picture quality that compares with room systems operating on ISDN Basic Rate Interface (BRI). Intel's ProShare Video System 200 achieves a $1,499 price by putting picture and audio compression on a plug-in board. It uses the host PC's CPU to decode the incoming bitstream and generate the on-screen windows. A minimum configuration of an i486/66 with 16 MB of RAM produces 176x144 pixel window sizes. With a 133-MHz Pentium processor, you can display 352x288 Common Intermediate Format (CIF) on a full screen. The latest entries in this year's charts are software-only solutions that start at $50. These require high-end Macintosh or Pentium CPUs and substantial amounts of RAM, but no extra c odec boards. Using a Pentium 166 MMX processor, the new Intel Video Phone supports H.324 full-duplex conferencing over V.80 modem-served analog telephone lines. Don't leap at these solutions until you've tried them in action. Few match the picture and sound quality of hardware-based codecs, and many have to use tricks like small viewing windows to achieve the appearance of smooth picture presentation. Full-screen displays look choppy and jerky.
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Updated May 23, 1997 |
