Tuesday, 7 April 2009


When it comes to CCTV, we live in an age of innocence

You'd think after all these years of walking along chatting on a mobile phone (cellphone), that by now the novelty would have worn off. And yet time and again I'm struck by the apparent simplicity of the concept against a backdrop of some quite spectacularly clever technology, that we all just take for granted.

It will perhaps come as no surprise that I'm actually old enough to appreciate a world before mobile communications, in fact I can still readily recall the immense effort required for my then young and spindly fingers to turn the old rotary dialler, on our ancient rattly old bakolite telephone.

Now you could be forgiven for wondering what the heck this has to do with CCTV, but quite by accident, I had something of a eureka moment the other day.

I happened to come across an interesting article written on the subject of video surveillance, possibly one of perhaps hundreds that I might chance upon in an average week.
What set this piece apart was not so much the content, as there's very little written on the subject that I haven't already seen a few dozen times before. 

No, what really set this apart, was not only was it written by a very thoughtful and articulate young lady in her twenties, but she also happened to be a resident of the United States that is currently studying in the U.K.

I've long been wondering about the precise mechanics of deterrence in relation to the way we attempt to use CCTV as a crime reducing technology, and how our experiences in the U.K. tend to suggest that there is something fundamentally wrong with the simple concept of 'cameras cut crime'.

I certainly know enough about the subject to realise that it isn't simply about using the technology, but equally it's as important to apply the correct techniques, and in so doing properly fulfil a defined and achievable strategy.

Now coming back to the young lady gracing our shores, her perception of CCTV and it's implications on our society, were reported by her to be very different from those of her british peers, and this simple observation was what finally caused the penny to drop.

Since successive U.K. governments started to fund the widescale deployment of Public Space CCTV schemes back in the '80s, that would mean that anyone under the age of 25, would not really  know a world without surveillance cameras. From their earliest memories of childhood, the cameras have always been there, albeit that it's only been in the last ten or so years that the installation of cameras has really taken off big time.

So on the basis that over here, people of a certain age have become generationally habituated to the presence of CCTV, barely concerned as to whether the systems are operating efficiently, or at all for that matter, it can't really be any great surprise that youth crime is stubbornly refusing to respond to a deterrence, which an older generation have naively invested billions in, and which to this day is promoted as a technological cure-all for societies many and varied ills.

There has to be something not quite right, when the old duffers think it's money well spent, and the target of their attentions, the less than bright young things ... just ain't bovvered.

As a society, we perhaps need to take a step back and consider carefully all the achievable objectives, and how best to focus resources on addressing the actions of the law defying, without continuing to routinely impact on the everyday lives of the law abiding.

Or then again, we could just keep on spending a large fortune on covering the country with as many CCTV  cameras as possible, and still have one of the least enviable crime rates amongst all of our european neighbours.

Decisions, decisions .....

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Monday, 6 April 2009


Does white van man have his eyes on you ...?

There's been a lot of controversy just recently about the launch of Google's StreetView service, where camera equipped cars are roaming the country snapping images of peoples homes, which are readily available over the internet for anyone that has an interest.

The fact that the vehicles are unmarked, and indeed carry no signage to comply with the Data Protection Act, shouldn't really provide any great surprises, and yet Google aren't really alone when it comes to having a quick snoop up the average side street.

Not for the first time in recent weeks, I've spotted a white unremarkable unmarked van, cruising past my door, with nothing to arouse suspicion other than the fact that each corner of the roof is embellished with an outwardly pointing CCTV bullet camera.

Rumour has it, the vehicles (of which there are many) are being deployed by the local councils in order to identify untaxed vehicles, using a database supplied by the Driver and Vehicle Licensing Authority (DVLA), which is compared against the images of vehicle number plates snapped by the passing van.

Now why would they want to cruise the streets of old London Town looking for untaxed vehicles.

The answer of course is clamping and penalty charges for release; so acting as agents for the DVLA, in the words of Arfur Daley they're on to a nice little earner.

And who said there's not much profit left in video surveillance ...?

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Sunday, 5 April 2009


The art of CCTV resolution, or reading between the lines?

Just prior to the G20 summit here in London, this CCTV news story caught my eye on www.guardian.co.uk.

Now I'm quite used to reading 'strange but true' stories about the mad things people do with video surveillance cameras, but this piece really did stand out simply because it's daftness could so easily have been mistaken for an April fool joke, and by all accounts, many indeed thought that it was.

The background is very simple; Londons Westminster City Council have invested £ 15 million ( about US$ 20m or € 15.5m ) in a "state of the art" mesh network enabled video surveillance system, using re-deployable dome cameras that are mostly fixed to street lights. 

At this point, I should perhaps mention that they've been happily using them for quite some time now, that is until the civil servants at the Department of Transport decided that with some new legislation coming into effect on the 1st of April, the cameras were no longer compliant and so would have to be switched off.

So that's about 60 street surveillance cameras deemed to be unfit, and condemned to be switched off, on the very day that all the worlds top brass buttons roll into town, amid one of the largest security operations ever seen in the capitol.

All makes sense so far ...? Well no actually, there was something rather odd about this story, repeated as it was across numerous news and media organisations; so I decided to do a bit of research to try and find out what all the fuss was about.

Now the first thing I discovered was the new legislation related specifically to the use of CCTV cameras, in order to issue Penalty Charge Notices (PCN's) for traffic violations. Now unless I'm misreading the situation, the cameras were ordered to be turned off, simply because they were deemed to be non compliant with the specification laid down for cameras, intended to be used for policing vehicle offences. 

I could be wrong here, but it doesn't actually follow that if the cameras cannot be used for issuing PCN's, then they can't in the meantime be used for something else, such as Public Space Surveillance, where no such mandatory specification actually exists.

So at this point, it becomes clear that the cameras could in theory continue to be used for street monitoring / public safety, but they cannot be used lawfully for issuing tickets, or what according to the great British public, is euphamistically termed "revenue generation".

That then conveniently brings me on to the next point of contention, which actually relates to the new legislation introduced by the Department of Transport.

The entire basis of the argument is over the difference in image resolution between 4CIF (in this case, the councils cameras that are imaging at 702 x 576 pixels), and the stated requirement in the DfT documentation which is a minimum of D1 ( 720 x 576 pixels).

Now there's actually a number of quite seriously daft issues here. 
Firstly, the actual difference between 4CIF and D1 may only be in the order of about 2.5% in practical terms, but in the real world, there isn't an engineer alive that could visually tell the two standards apart if the pictures were presented for viewing in isolation.

That said, there is a glaringly obvious mistake in attempting to relate image quality in relation to resolution, by simply stating the requirements in pixels. That is an absolute no, no in my world, for reasons I won't bore you with at this point.

The correct way to lay a standard for resolution, is by stating a requirement for both vertical and horizontal resolution, measured in "lines", with perhaps a + / - 10% to allow for what goes on in the real world.

For example, if the camera, transmission system and recorder are all optimised for D1 quality, the lens may be within spec at 2.10 pm on a monday afternoon, but twelve hours later, as the iris opens to allow night coverage, the resolution produced by the lens could easily drop 10 - 20%, so in theory making the entire system underperform, and therefore prove to be unfit for purpose according to the minimum specification.

Likewise, atmospheric grime deposited on the cameras dome or window, could quickly reduce the resolution by anything up to 30 percent or more, which in itself presents an interesting situation for anyone wishing to challenge the legality of PCN's issued using a CCTV system, which may well be unwittingly, unlawful in nature.

Despite numerous attempts to find a reference in the documentation, it would appear that unlike the widescale use of 'speed guns' which are used for tackling motorists travelling over the speed limit, there doesn't appear to be any mandatory calibration process required, to ensure that the CCTV cameras are operating 'on spec', most of the time. 

There isn't even a statutory requirement for regularly cleaning the camera's to maintain quality; it simply states that a camera should be kept clean to help maintain the image performance.

I suppose the bottom line is, the difference between 4CIF and D1 may only be a couple of percent in terms of potential resolution, but the difference between using notional pixels and actual resolved 'lines' as a measure of image resolution, is quite literally worlds apart.

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Happy new CCTV year .... again!!

Well that just goes to prove it .... I said way back in January that my new year's resolution was going to be a concerted attempt to spend far more time blogging about CCTV and the meaning of life. 

So what do I do?, well not a lot to be honest, until that is I discovered quite by accident that last week was yet another New Year celebration, this time in Iran.

Having promised in the new year to post more stories about video surveillance, now at last I can actually fulfil my obligations, albeit that I'm probably about three months later than perhaps I should be.

Oh well, the brain is willing but the body is otherwise occupied; that's my excuse and I'm sticking to it.

Anyway, if you come across any interesting CCTV or IP Video related news stories, why not drop me a line and I'll make sure they get seen by a wider audience.

In the meantime, if you happen to know any of the words to Auld Lang Syne ....

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