Main Issues To Consider Before Installing A Home Surveillance System
When people think of surveillance systems they usually have in mind the sort of CCTV cameras now so prevalent in shopping malls or those sinister looking security cameras mounted high up on buildings to deter would be intruders. But in fact the technology behind security cameras has developed apace in recent years and now it is both easy and affordable to install your own home surveillance system.
But as always seems to be the case with modern technology the main problem is most definitely not lack of choice. In fact the options available to anyone thinking about installing their own security cameras are quite bewildering. Let’s quickly cover some of the many and varied permutations to consider before looking at each in more depth. Some decisions obviously impact on the other possibilities, for example if you want to monitor your cameras remotely from a computer you will need to capture digital images and have the capability to stream these via a network link.
First there is the basic underlying technology, in other words the more established analogue videotape versus modern digital imaging. Then there are factors such as indoor versus outdoor, location in general, low-light capabilities, monitoring of the system, security of the captured images, picture quality, control over camera zoom and pan etc. The list goes on, but that’s probably enough to dive into for an introduction to this topic. The way to resolve many of these issues is simply by focusing on the exact purpose of your system. Is it to collect evidence, deter unwanted visitors, maintain a record of events, make you feel safer or a combination of factors?
Comparison Of Security Camera Technologies
CCTV Monitors
Cameras that send analog TV pictures are simple and being old (or as some might argue, obsolete) technology are also fairly cheap and robust. These are essentially closed circuit television cameras (hence the acronym CCTV which is now loosely and inaccurately used to describe any kind of surveillance camera system). In order to also record as well as monitor events they are usually hooked up to a video cassette recorder (VCR).
The downsides to this technology are many; for a start, although there is invariably a means to detect motion and not waste video tape when there is nothing worth watching, there is no means to send alerts. Also the picture quality is pretty low-grade and the camera and recorder have to be physically linked, which constrains how far apart they can be. There is also a problem with video tape which is that you have to regularly change tapes otherwise any recording is lost, and should an intruder simply break in regardless they can quite simply steal the tape anyway, thereby totally defeating the point of the system. Although is still has a place in commercial applications, for a home system, analog CCTV is a poor choice.
Web Camera Security Systems
The first use of digital cameras for the home security surveillance system was with Web Cameras (or Webcams). These obviously capture digital still images that can be rendered as a motion video by playing them at the same frame rate as they were originally taken – the closer together each picture, the smoother will be the motion. The images are stored on a computer and by installing some software (that is often available as a free trial download) called typically a webcam monitor you can add features such as customisable motion detection, scheduled recordings, alerts, remote upload and monitoring, and a whole host of useful options. The downside of a webcam is again cabling limitations since it has to be within a reasonable distance of a computer, but they are an effective low-cost solution for many domestic and small business situations (shops and offices for example).
Wireless Network Cameras
The latest breed of home security cameras is represented by the so-called IP camera (also known as either a network security camera or wireless network camera). The acronym IP stands for Internet Protocol and means that these cameras are basically stand-alone network devices that look to your home network pretty much like other computers. They are configured on the network just like anything else, using either a physical Ethernet cable or more commonly their built-in wireless network adapter.
There are many advantages to wireless security camera systems. They only require a power supply and don’t need to be in proximity to a recording device, and are also lightweight and typically very easy to install. You can monitor and record multiple cameras from multiple locations (including remotely) and of course if the images are automatically uploaded to the internet then there is nothing physical to steal and thus no means to remove evidence after it as been captured.
In common with earlier webcams, IP cameras provide a default set of extremely useful capabilities that rely on the properties of digital imaging. So smart motion detection, compression of images for mass storage, remote control of the camera and a variety of digital image enhancement techniques are all possible. There is also the means to set schedules and alerts and arrange to be notified via email or mobile phone so you can instantly check to see what’s going on.
The weakness with any wireless camera system is that it relies on having an internet connection. This means that the domestic wireless router needs to be powered up and have access to a functioning telephone line. In particular, if the phone line into the house is exposed it could easily be cut (though if you had already captured images of the intruders first, as is quite likely, then it would be too late for them anyway since the images are uploaded more or less instantly).
Another, probably far more common, exposure is the security of the router itself. If you wander round your neighbourhood with a wireless enabled laptop you can scan for other wireless networks and you might be surprised to discover a) how many there actually are and b) how many still use the default unsecured settings that shipped with the router. That said, if you are aware of these issues you can take steps to both protect your physical phone line and secure your wireless router.
Infra-Red Security Cameras
At a tangent to the main topic of camera technologies there is also the consideration of low-light or even total darkness capability. Infra red cameras are nothing new, but again in the field of IP cameras you can acquire a reasonable hybrid conventional and infra-red capable camera that automatically self adjusts between the two modes and is fairly modestly priced.
In summary then, unless you have a compelling reason to go with the older CCTV and video tape based security systems, the best option is without doubt to install an IP camera based surveillance system. It will be easier to install and maintain and provide vastly more capability.
Determining The Best Location For A Domestic Surveillance Camera
Camera location is determined by a number of factors, such as best position to view whichever aspect you wish to monitor, how robust the camera is, external visibility of the camera, and simply access to the desired location.
The most obvious issue to resolve first is what exactly you want to monitor. Is it inside, outside, multiple point of access? In other words, determine how many and what type of camera(s) you need. Some cameras are not weatherproof for example and others might struggle if the area you wish to monitor is generally poorly lit. Above all, try to ensure some level of compatibility between your cameras so that they can be integrated into a single system. In particular, check that IP cameras support the same levels of wireless security as each other and as everything else currently hooked into your home network (i.e. WEP versus WPA encryption).
External visibility comes down to whether you want people to see that you have a surveillance system in operation or whether you want to capture evidence covertly. There are of course situations where you might want to do both, but you need to settle this issue first as it will determine both what type of cameras to purchase and where to fit them so they are either very obvious or difficult to detect. When going for the high visibility option it clearly helps to use larger camera casings and to also consider adding in a few dummy security cameras since it’s hard to spot a fake security camera at a glance, especially if genuine ones are in the mix. Another effective strategy is to install one or more infra-red outdoor cameras since these provide good visual deterrence at night due to the very obvious IR LEDs that glow red in the dark.
If your aim is to capture effective images then you need to carefully identify specific locations that allow your cameras the best field of view. You will often need to apply some lateral thinking and do some testing to get this right since it probably won’t be obvious at first that, for example, you’ve set your camera up so that you can only see the tops of peoples’ heads or that everyone who comes to the door has their face obscured by part of the door frame getting in the shot. In all cases though, whether or not you want your surveillance system in full view, make sure you locate your cameras out of harm’s way – either high up or indoors.
Features Commonly Available On Wireless Network Cameras
Where to start? Modern IP cameras are literally bristling with all kinds of smart features. Perhaps one of the most obvious is the way that motion detection is implemented.
Traditionally, infra red motion sensors were used, similar to those that set off your outdoor security lighting when someone approaches (or a nearby tree rustles). Digital cameras however mostly detect motion by comparing the actual image from one moment to the next and evaluating how many of the pixels have changed thereby indicating that something has moved. In earlier IP cameras this was done by simply working out what percentage of the image was different and how quickly the change had occurred.
These threshold and sensitivity parameters could be set by the user of the camera to best suit their own environment but it was nevertheless rather crude and prone to either triggering false positives or missing genuine motion if not set correctly. Modern network cameras have improved the algorithms used to detect motion and are now capable of independently monitoring separate portions of the image rather than relying on a total pixel count. Regardless, this technique detects visible changes to the scene rather than inferring motion indirectly from IR detectors and is thus far more accurate.
From the first, network IP cameras were able to route image data simultaneously to both an IP address on the web and to a local computer from where an alert or the images themselves could also be forwarded via an email to a mobile phone. The latest models now also feature integrated SD (Secure Digital) card support which means that each camera can store a copy of its own images in addition to (or instead of) routing them to a central repository. In essence, this frees the camera from total reliance on the presence of an active network connection provides a redundancy/backup capability and unlike video tape, SD cards can be configured to loop so that old images are replaced with the latest ones.
The ability to “operate” the camera by varying pan, tilt and focus is typically not found on IP cameras aimed at the domestic market and to be honest there is very little need for such functionality. After all, the point of most home surveillance systems is to passively monitor your property when you’re not there, not to have you actively monitoring and adjusting the camera when you’re away. Most though do allow you to dynamically monitor a number of cameras remotely in real time using what is termed Dynamic DNS service support for cameras connected to external dynamic IP addresses (don’t worry, the installation manuals invariably step you through how to set this up even if you don’t really understand how it works).
Many IP cameras include a built-in microphone to record audio which can be especially useful for applications such as monitoring a baby sitter for example, however quite a few also have two-way audio allowing you to communicate with whoever is being monitored. This has obvious uses as for example a gate or door monitor, or simply to scare off unwanted visitors.
Infra red night vision is a feature that has been around a few years now, but on old and/or cheap IP cameras you will find that the infra red detectors are on all the time which has a detrimental affect on daytime picture quality, particularly the way that some colours appear. The latest (and more pricey) versions use an IR cut filter which does what it sounds like – cuts out the IR component when it’s not needed. If you do need to monitor an area that is dark at night then infra red is an option worth choosing, though a cheaper alternative is (if it’s possible) to simply install a passive IR light triggered by motion that illuminates the scene well enough for a regular camera to work.
The latest technology to find its way into network cameras is PoE, which stands for Power over Ethernet and enables a single cable to carry both electrical power and data signals. It can be extremely useful in situations where access to a power supply is a problem or simply as an alternative to using conventional power cables. The other advantage of using physical Ethernet cabling is speed and reliability – it’s both much faster and more secure than wireless communication.
And that in a nutshell concludes this quick skim through what’s available out there for anyone wanting to build their own home surveillance system.
