CCTV, Why?

We are the most watched nation in the world, we have the most cameras per person and statistics have shown on average we could be caught on a CCTV system a hundred times a day. How many times have people been convicted on the strength of a CCTV image alone? It therefore begs the question CCTV, why?

It's true most CCTV installations are often a knee jerk reaction to an incident or to an environment. For instance a school is broken into and computers are stolen, suddenly CCTV cameras are a must, a local installer is called and a "CCTV system" is installed. The school down the road hears of the incident and calls the head teacher who passes on the details of their installer and another "CCTV system" is installed. It spreads like a virus and suddenly the whole area is saturated by CCTV cameras, all purporting to provide protection from theft or violent crimes, to such an extent the local council feels it needs to install them in the street to make local people feel safe.

So is the school any better protected because of the cameras? Probably not, the cameras them selves may act as a deterrent (no body likes being watched while committing a crime) but can the school afford to have security out of hours watching the video streams constantly? The majority can not. The thieves are aware of this and commit the same crime this time wearing hoodies and masks, the next day the school have some grainy images of shapes that look like people carrying off the schools computers again. CCTV failed, and yet so much faith is put into these systems to protect property and people, so will the CCTV system be updated? No the school can not afford it. So CCTV, why?

The problem is not in the concept of CCTV but largely the application of the CCTV and often the installation of the system, promising more than it is delivering. The Home Office recognised the need to provide a means of giving guidance to CCTV installers, the trouble is its a large document not very easily found and most CCTV installers will never have read it. Find it here. You also have the problem of competition, installers undercutting with cheaper systems which can not provide the cover needed. It has to be said that any system is only as good as the monitoring applied to the system, going back to the school scenario had the video been monitored then the thieves could have been intercepted, so no matter how good the CCTV system was if its not monitored then its not fit for purpose.

Compounding the issue is the recording of the video stream. To record the stream the image must be converted into a file format which can be read by devices after being archived. These range from tape recorders to disk storage devices. However the act of recording the image degrades the quality which is the reason when we see CCTV images on the TV of recorded video streams they always look fuzzy and unrecognisable. This is caused by compression techniques used to increase the total recordable space needed. So CCTV,why?

What about IP?

OK so i have been deliberately negative toward CCTV systems but all of the above really only applies to analogue in general. The home office document still applies to IP cameras systems which we will call IP security cameras systems (IPSCS) as CCTV does not describe an IP based system and is only really similar in its goal but not its application, i want to make the distinction between the two types of systems.

IPSCS's are not the cure all but it does make the concept of video surveillance work. It has lots of nice features which means IPSCS's systems are not limited by the physical limits of CCTV.

Subject Image Size

There are many applications of a security camera, should you be looking at a crowd you will want a large detailed image to see any incidents but should you want an door entry camera you will want the subjects face to occupy as much of the screen as possible. In the Home Office document its referred to as Monitor, Detect, Observe, Recognise and Identify (see doc for more detail) various sizes of the subject relative to the screen size. This describes the function of the camera, if you are looking at a car park then monitor is the goal and a suitable camera can be used or if you are capturing faces at an ATM machine then identify is the goal again a different camera would be specified. With IP cameras this blurs the boundaries of these classifications as a mega pixel camera may be able to monitor and provide identification due to digital zoom. This dual functionality can be achieved with in the analogue world with a PTZ camera, but not in the same way. With an analogue PTZ (pan, tilt and zoom) camera any time you zoom into a scene the surrounding area is lost and only what the camera is looking at is recorded, so while identifying the camera is no longer monitoring, its an either or situation.

Mobotix cameras are a perfect example of a well engineered IP surveillance camera (IPSC) and in many situations one camera can replace three to four analogue cameras. They have no moving parts as only digital zoom is employed and the image that is processed is a true digital 3.1 mega pixel image not a re-engineered analogue camera with an encoder bolted on. Unlike a fixed zoom analogue camera the subject size can be changed to match the required size to provide an all round camera function in line with the Home Office guidelines.

Event Notification.

In our opening example the school could not afford to monitor the CCTV round the clock and so the thieves got away, how can an IPSCS help? There are two ways to help with monitoring you can configure the cameras to monitor the areas of interest for movement and once movement is detected then send warnings with pictures via email, sms or in some cases as with Mobotix cameras the camera can make a call to your mobile alerting you movement has been detected. Doing away with the need to have round the clock or out of hours monitoring.

Brining it all Together

There is another way, its true i am pro IPSC and will always look to fulfil a surveillance system with IPSC but an application like Milestone can take video feeds from various camera manufacturers and even analogue cameras (via encoders) and unify the camera streams under one common interface and management system. So should the camera not have the ability to monitor movement then Milestone can provide that in software helping current analogue system migrate seamlessly into the IP world.

Storage and Loss of Image Quality

When storing the images as can be seen in my previous blog even in the IPSCS world how you record the image can have a massive impact on retention of your initial quality. What you see might not be quite what you get. In the analogue world this is amplified to an even greater extent. The largest image possible in the analogue world is 4 CIF or .4 mega pixel when this is recorded and compressed it will be reduced to .1 mega pixel rendering the images next to useless. Milestone comes to the rescue again, as an encoder will not degrade the image quality when converting it to a digital stream (depending on the codec used, see previous blogs) so Milestone can record the image at close to the .4 mega pixel not a patch on IPSCS but better.

IPSCS Why?

So IP and its associated technologies actually makes the concept of security via video work better. Its not the cure all but its a very large step in the right direction. Compared to CCTV it really does work and makes your investment give you the protection you are paying for. This is just looking at a plain IPSCS system without the addition of analytics packages which can further extend the power of your IPSCS (a topic for future blogs). So if you want your CCTV system to be an investment in protection and actually live up to what is promised then install IP based CCTV an IPSCS or if you have a CCTV system then Milestone can be your champion in putting the analogue streams on an IP based system.

The bottom line is if its not IP why CCTV?