Not so long ago, the abbreviation 'IP' was understood in the information technology world to mean Intellectual Property. Now, it most strongly stands for Internet Protocol, a term that just about everyone, from kids to grandparents who have PCs, are familiar with.
It is therefore no wonder - and no accident -that we find IP as closely connected (literally) to CCTV surveillance systems as to computers and, more recently, to telephony. The 'no accident' refers, of course, to the logical developments of digital technology combined with the virtually universal availability of the Internet and all that it allows.
This article looks at what is happening with IP surveillance systems, touching on their introduction and relatively rapid acceptance and, finally, outlining what we can expect to see in the short- and longer-term.
The digital jump to IP
As in the broadcast world, it is generally accepted by surveillance professionals that digital is the way forward, and certainly for the longer term. That is to say that there will continue to be some, though decreasing, demand for hybrid, combined analog/digital systems in the short- to medium-term. If the transition from analog to digital CCTV systems, strongly aided by the advent of the digital video recorder (DVR) can be regarded as a quantum leap, it is just as true to say that IP-based surveillance is an equally important leap (see 'Advantages of IP surveillance systems' below). Numerous enterprising manufacturers have, therefore, already invested in digital technology and, carrying their investment a step further, into IP-based products and systems.
The telecommunication industry nowadays is an excellent example of making full use of IP for carrying virtually any medium, from voice, video and pure data, to and from optical, copper and wireless networks, be they LAN, WAN or even the Internet. In other words, 'anything over IP and IP over anything', made easy by Ethernet transmission.
Ethernet has long been the most efficient medium for data transmission, chiefly because it allows the use of wide bandwidths, it can be easily and seamlessly integrated into existing IT infrastructures at low cost and is a global standard. Moreover, because it relays signals simultaneously and camera images up to 30 images per second (ips), it is an ideal network solution for surveillance systems, particularly using IP and powerful software.
NVRs, not DVRs
Having mentioned the importance of the DVR in digital CCTV systems, it is, however, not the best means of recording images in an IP-based system. The three main reasons are 1) DVRs are not scalable (adding cameras has to be in multiples of 16, for example); 2) recorded images are sub-optimal in that they have originated from analog cameras, have been sent through varying lengths of coax cable and then converted to digital and compressed by the DVR for each batch of 16 cameras; and 3) the higher the frame rate, the more processing power per channel is needed, the more DVRs are needed for recording, and the greater the cost. In other words, DVRs are expensive.
The answer is the NVR, or networked video recorder, a pure software solution that operates on standard platforms with an 'intelligent' server PC and a large number of hard disks. The NVR can record from any camera, at any distance, and play back to any monitor. It offers almost unlimited storage of a high number of video channels.
In addition to the singular advantages of the NVR as the key enabler of LAN or IP-based networked installations, it is important to highlight those of the networked camera. These include individual analog-to-digital conversion and compression within the camera, and optimisation of lenses, CCD functionality and digital signal processing (DSP), to produce a high-quality image ready for viewing and recording. IP-based cameras are now being developed that will have innovative features like megapixel resolution for very high-quality imaging, remote PTZ control without additional cables and power-over-Ethernet (PoE), which also saves on cabling and facilitates connection to an uninterrupted power supply (UPS).
Having overcome initial skepticism as to its suitability and established as a global standard in 2000, MPEG-4 is the compression technique now generally accepted in digital CCTV systems. With its high compression rate, MPEG-4 can easily handle video streams of 30 ips without compromising image quality. M-JPEG, the compression technique most commonly used before MPEG-2 and MPEG-4, has almost entirely been dropped. And once users experience the storage benefits of MPEG encoding they will never want to use M-JPEG.
Efficient, multitasking encoding and decoding of video data are essential to the operation of the IP-based network. Today's video transmitters/receivers, such as Bosch's VIP series, are ultra-compact, fast and support full PAL or NTSC sources and full-duplex audio. VIP transmitters/decoders are also suitable for both MPEG-2 at full D1/CIF and MPEG-4 at 4CIF/CIF/2CIF, as well as multicasting and Internet streaming through a FastEthernet interface. Dual encoding makes best use of storage, by recording with different parameters than with viewing. In receiver mode these products can be used to integrate box-to-box connections in the network to show video from any MPEG-4 transmitter on analog monitors.
In full control
An IP-based surveillance system can operate without network control. But, with a correct management tool, controlling and managing the system can greatly facilitate its operation. Again, recent advances in digital technology have helped in the development of sophisticated network control solutions that are, today, mostly pure software.
There seems to be no limit in finding innovative ideas in the security and surveillance world. Most experts agree that Moore's law applies just as equally to digital CCTV systems as it does to electronic miniaturisation. Although the prediction in 1965 that the number of transistors per square inch on integrated circuits will double every year has slowed down a little, data density has still doubled approximately every 18 months. The innovation is not only in the system hardware and software components, it is also in the applications. In fact, thinking up new applications becomes the challenge for manufacturers to provide the solutions. And sometimes the development of a new product itself creates the opening of an application previously not thought feasible.
One of the key areas where innovation in application has stepped in is video content analysis (VCA) that uses realtime and recorded images and compares them with a database. Some typical applications include:
* Automatic number plate recognition (APNR) - for example, detecting a stolen vehicle, authorising entry to private car parks or detecting non-payment at filling stations or automatic payment at toll gates.
* Facial recognition - iris or full-face recognition for personnel entry authentication, or tracking criminals.
* Behaviour recognition - pattern recognition of certain movements of people that suggest suspicious behaviour.
* Traffic volume - counting the number of vehicles on roadways or number of people in a shopping mall.
* Static objects - suitcase or other suspicious object at an airport or inside a building that has not moved for a period of time and does not seem to have an owner.
* Product bar code - reviewing sales of retail items in a shop to avoid errors in pricing and maintain inventory.
These, and many other interesting, labour-saving applications are rapidly emerging as the flexible, accessible, scalable and cost advantages of IP-based surveillance systems are being proven in practice.
Taking the surveillance system a few steps further, there are manufacturers (like Bosch) that also develop communication, fire, intrusion alarm and access control systems. We see more integration of one or more of such systems with CCTV, to provide a total, integrated security and control facility in enclosed spaces, for example, department stores, shopping malls, airports and prisons. The historical (even cultural) objections to using the existing Ethernet infrastructure for more than just the computer network are being overcome through education, technical solutions to data sharing and bandwidth, and through necessity.
It is firmly established that not only is 'digital' the way ahead in CCTV systems, but IP-based or enabled is the real future. IP systems are surprisingly affordable - possible initial (higher than analog) component costs are counter-balanced by savings in installation, maintenance and total-cost-of-ownership (TCO). Today there are IP surveillance solutions for both small, simple systems and for complex, large enterprises where economies of scale apply. It is only a matter of time before IP becomes the only way ahead.
Ruud Toonders is a digital CCTV product marketing manager at Bosch Security Systems, Eindhoven, The Netherlands.
Advantages of IP surveillance systems
* Scalability and flexibility - unlike CCTV systems with a DVR, cameras can be added in increments of one up to hundreds, or even thousands. Frame rates and storage can be increased at any time and at any place in the network, simply by adding more hard drives and servers.
* Camera functionality - 'intelligent' functionality within the camera, including motion detection, sensor input, relay output and alarm triggering - combined with high-quality digital images. Dedicated IP cameras with progressive imaging and megapixel resolution overcome the limitations of PAL/NTSC.
* Cost-effective infrastructure - existing two-wire LAN or Internet cabling can be used. Even if installing a new infrastructure, two-wire cabling is much less expensive than coax.
Open standards - global standards as used in IT infrastructures allow cost savings through use of open system components and interoperability with other networks, including compression and wireless connectivity technologies.
* Network functionality - one network manages audio, video and data with remote and shared availability through both wired and wireless connection, for optimal accessibility and cost saving.
* Reliability - maximum reliability is assured through redundant infrastructure and management software that provides realtime health status of the entire network and preventive maintenance.
* Accessibility -realtime or recorded images can be accessed from any location where Internet is available, for further convenience and cost savings.
* Cost of ownership - a total system approach with software components has proven to be more cost-effective than 'black box', for both installation and operation.
* Wide area connectivity - virtually limitless connection of cameras and image transfer for a broad range of applications, enhanced through wireless technology.
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