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Before you don your hoody and pop down to the local shopping centre or high street for a spot of yobbery or shop-lifting you might like to ponder the following question: what do Renaissance painters, flying saucers and out of favour saints have in common?


To save you guessing the common thread is cutting-edge CCTV video surveillance. The flying saucer reference will become clearer in just a moment but the connection between Big Brother keeping his beady eye on you, artists like da Vinci and Holbein and disreputable saints requires some explaining…


It concerns a rather clever trick pioneered by the master painters. Every so often they were commissioned to do a portrait of a saint or a woman that for various reasons, the commissioner preferred not to be recognised. Their solution was a technique known as Anamorphosis -- from Late Greek, meaning to transform -- whereby the image was highly distorted making it totally unrecognisable. However, when the painting is viewed in the reflection of a curved or cylindrical mirror it regains its correct proportions and all is revealed.


That brings us back to CCTV and a new video surveillance camera that bears a striking resemblance to a small flying saucer. It solves a long-standing problem for the security and surveillance industry, namely keeping watch over us in large busy areas like shops and commercial premises. Until recently the only way to do that was to install multiple fixed cameras, hopefully pointed at the places where mischief is most likely to occur. The more flexible alternative is to mount cameras fitted with zoom lenses on motorised ‘pan/tilt’ platforms (known in the trade as a pan/tilt/zoom or ‘PTZ’ cameras).


Fixed camera and PTZ installations generally involve a compromise of one sort or another, either requiring the CCTV operator to keep a close watch on banks of monitors, or be sufficiently alert to point the camera in the right direction at the right time. Potentially important events are frequently missed because the operator is either looking at the wrong monitor, or in a daze, bought about by ‘monitor fatigue’.


The new saucer camera, which can be either ceiling or wall mounted, has a single ‘fisheye’ lens giving a full 360-degree hemispherical view of the surrounding area. The resulting image is grossly distorted and all but useless for observation purposes but this is the clever part. Advanced digital image processing -- the equivalent of the painter’s curved mirror -- corrects the distortion and displays any part of the fisheye view in its proper perspective so that it is almost indistinguishable from the picture coming from a conventional CCTV camera.


Normally this level of processing, and the fact that only a small portion of the whole image is being displayed would result in a drastic loss of definition but the manufacturers have thought of that. The camera uses a high-resolution image sensor chip with between three and five times as many pixels as a normal CCTV camera. Incidentally, the reason the camera is flying saucer shaped, and covered in metal fins, is to dissipate heat the generated by the hard working processing chips.


Nothing can escape the saucer’s all-seeing eye. It can generate fisheye and panoramic views plus up to four simultaneous ‘virtual’ camera views from any part of the fisheye image -- all together on one screen if required -- or the operator can pick a single view and ‘steer’ the camera to move in for a detailed close-up using an electronic PTZ system. A motion tracking facility automatically locks on to movement and follows the subject or object wherever it moves in the image area. In fact there is no need for an operator at all and the camera can be programmed to ‘tour’ the image area, concentrating on entry and exit points, monitoring for unexpected movement.


News that CCTV cameras are getting smaller and a lot smarter will come as no surprise to most people but developments like this means there could actually be fewer of them in future. However, villains, civil libertarians and those made uncomfortable by saturation video surveillance have little celebrate. In this case less means more, one strategically placed saucer can do the work of half a dozen fixed cameras so not only is Big Brother watching you closer than ever, now he’s got eyes in the back of his head…




Ó R. Maybury 2005 2705



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