By using standard telephone networks to transmit and receive live video, considerable cost savings can be obtained over dedicated communication alternatives for Intelligent Transport Systems (ITSs). This article describes some off-the-shelf products that are now available to support such flexible video-based telephone systems. This will open the way for value-added traveller services. Prism Video, Inc. was a pioneer in this field, and began to develop its technology in 1987. This company is expert on video compression-decompression (CODEC) algorithms, whose efficiency is a function of the programmed ability to send a video in a digital mode over a telephone line's very narrow bandwidth. Prism implements its proprietary CODEC algorithms on an ASIC chip, and uses one board for video capture, and one for display. Its technology operates on telephone lines, ISDN, cellular telephones, V-SAT, and radio; its hardware is addressable in the Internet's TCP/IP environment. SmartRoute Systems is a company that plans to use Intelligent Transport System (ITS) technology and benefit from Federal and State US programmes to fund them. Its system updates all records approximately every six minutes, to allow road users to avoid congested routes in time. It has been awarded contracts for installing its system in several US states.
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