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‘Single’ or ‘Multi-Vendor’ IP Video CCTV Systems – Choosing the Right Path
It’s becoming increasingly important that end-users understand the difference between ‘single’ and ‘multi-vendor’ IP Video systems. Marcus Kneen, IndigoVision’s CEO, discusses the advantages and disadvantages of each approach and their impact on choosing a system. With IP Video technology set to dominate CCTV ov er the next f ew y ears, the question of whether a sy stem is ‘integrated’ (single-v endor) or ‘open’ (multi-v endor) is a recurring theme within the industry. Do any standards f or IP Video sy stems exist? Can y ou buy products f rom dif f erent manuf acturers and expect them to work together? This article seeks to clarif y some of these questions and sets out the key considerations when choosing an IP-based digital CCTV sy stem.
The Standards Myth
Many people in the industry believ e that so called ‘open’ or ‘multi-v endor’ IP Video systems achieve their interoperability through the use of open industry standards. This is a my th. There are a number of aspects to IP Video that are genuinely standards based. One of these is v ideo compression: MPEG-2, MPEG-4, H.263, H.264 and jpeg2000 are all ratif ied standards and commonly used in the IP CCTV industry . These f ormats only cov er digital compression and decompression of analogue v ideo, not the liv e streaming of the digital v ideo. IP Video sy stems require digital v ideo to be transmitted in real-time around the network and f or this a transmission and control protocol is required. These protocols are transmitted using the Ethernet IP network standard, which allows IP Video to co-exist with other network traf f ic such as general computer inf ormation. There are many transmitters on the market that use standard v ideo compression y et depend on proprietary streaming protocols. It is the transmission and control protocol that is the most non-standard element in the sy stem, howev er, it is this element that allows many of the adv anced f eatures f ound in IP Video sy stems to be realised. The protocol contains a number of basic commands that, f or example, allow the v ideo recording to be started and stopped, an alarm to be sent or a camera to be panned. Ev ery manuf acturer uses their own protocols and without them the sy stem cannot work. Add v ideo analy tics to an IP sy stem and the complexity of the protocol is dramatically increased. There is a similar situation with analogue v ideo sy stems where the v ideo transmission is standard but the PTZ and matrix controls are proprietary . The reality of ‘open’ sy stems is that the v ideo management sof tware has to interf ace to each of the dif f erent v endor’s equipment using separate proprietary protocols – f ar f rom a standards based solution.
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