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Minding the shop

Controlling shrinkage with IP video.

HiQ Lifestyle is a fitment centre in Germiston fitting tyres, batteries, shock absorbers and exhausts. Like most such centres, it is wide open to the public and a hive of activity most of the day, with customers coming and going all the time and staff constantly handling stock that has wide appeal and is highly tradable. Also like most such centres, control of stock to prevent what is euphemistically called `shrinkage' is a constant battle.

Hermann Erdmann, the owner of HiQ Lifestyle, wanted a way to keep an eye on the operation. He could not be everywhere at once, nor could he be on site at all times, and to compound the problems he was in the middle of significant renovations following a fire. He approached Cirrus Techvue to look at putting a video monitoring system in place despite of having had a less than satisfactory experience with a disused camera surveillance installation some years previously as he believed that the technology must have improved.

The technology has indeed moved on, most significantly with the introduction of digital network cameras. While the initial cost of the cameras was higher than analog CCTV cameras, the ease of installation and integration into the existing network meant very little cost to be incurred after the initial purchase of the cameras and monitoring software.

Integration with the existing network

HiQ Lifestyle had an existing 100 Mbps network serving nine PCs. Adding a planned eight Axis network cameras was well within the carrying capacity of the network, so all that was required was to add a PC to act as the video monitoring and storage server and link the cameras to suitable network points. The physical constraints required two of the cameras to be wireless. Experience showed that the variability of wireless links and conflicts with wirelessly-connected PCs caused some intermittent connection problems; the solution was to add a wireless access point on a separate channel dedicated to the cameras. See Figure 1.

Figure 1. A camera's built-in web server accessed over the Internet

Storage

The cameras are set to monitor 24 hours a day in VGA (640x480) resolution, potentially generating very large volumes of data. Data requirements have been reduced by tuning the camera settings so that they transmit (and are recorded) only when they detect motion, with one second pre- and post-trigger buffering. Exclusion zones defined in the cameras prevent triggering on events of no interest: flags fluttering in the breeze, traffic on the road outside, and a palm tree waving in the wind were masked out. In addition, frame rates were cut down to five frames per second.

Nonetheless, significant storage is required to keep the target of 60 days history: the video server PC is currently equipped with 600 GB of storage for video data.

Strategically placing the cameras now provides 24-hour monitoring of the shopfloor, stores, and entrance gates and areas, addressing the need to keep a constant eye on the business.

Remote access over the Internet and GSM cellular

The need to monitor activity when not on site was met by providing password-controlled access to individual cameras and to the monitoring software over the Internet. HiQ Lifestyle uses ADSL for Internet connectivity. ADSL is relatively economical by South African standards but it does not provide a fixed external IP address. The problem was solved by using Dynamic DNS to provide a fixed domain address that dynamically adjusts to changes in the Telkom-allocated IP address. Access to the video functions is mediated through an ADSL firewall router.

Erdmann is often away from the office and not always able to get access to a PC, but Axis provided viewer software that runs on his 3G PDA, giving him access to any camera, at any time, wherever there is a cellular signal available. See Figure 2.

Figure 2

Erdmann's verdict: "I wanted a system to control stock loss. I found it did a great deal more: within a year it had provided video evidence of a driver who reported for work drunk and became abusive; it allowed me to monitor building operations when I was on leave; and it identified a case of 'sweetheart ringing' at the payment point. I can pinpoint problems and identify who did what, which not only eliminated stock losses but also improved quality because people are accountable. Usually it was nobody's fault, but now we can see who's fault it really was. It allows me to see how busy the shop is, wherever I am, and to be in control of my business at all times."

Figure 3. Quad view from the monitoring software, accessed over the Internet

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