Video surveillance system for gas/petrol station

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CASE STUDY
The crimes most often committed on gas station are drive-off gas thefts and lifts of various car accessories or other things being sold at the station. An increasing number of armed robberies at the stations is related mostly with relatively big sums of money, collected in cash registers and safes, and inadequate protection of those places. Small number of employees - often one person, and big distance from the police station or monitoring center make the stations an easy aim for common thieves and organized criminal groups.
An alarm system protects the station mainly from burglaries, but not from direct thefts, happening during opening hours (often round the clock), when every potential perpetrator may come in. Apart from thefts of gas and offered goods, there should be taken into consideration possible stealing from customers cars and acts of vandalism.
Well designed and reliable video surveillance system is one of the main factors that can improve safety levels at every gas station. Lower prices for more advanced solutions make such a system very cost-effective nowadays.
DESIGN GUIDELINES
Before we start to design a system for a gas station, we should consider what we really want to monitor and record.
The answer should be: appearance and facial features of people and detailed images of vehicles (make, color and registration number). Having these guidelines in mind, we can plan the deployment of surveillance cameras.
The locations that should be monitored include the places where cars drive in and stop, the pumps, the entrance to the store, the interior of the store, cash desk/s, and the exit.
Pumps
The observation area should be confined to the car standing by the pump. It will enable to get detailed images including the registration number and driver's features. It is also important, when the pumps are located in one row, to apply two cameras - one on the front and the second at the back. Such arrangement will prevent blocking the view of the second car.
The camera/s should be mounted at optimal height allowing, on the one hand, good visibility of registration plates (not too high - when the plate is viewed at an angle, it decreases readability), and on the other hand - not too low (to avoid damaging).
Entrance and exit
Observation of the cars driving in and out is a good solution because not every car will get gas. Some cars may be parked outside the monitored area and the driver or passengers will only buy something in the shop. Monitoring of the entrance/exits solves the problem - but the cameras should be placed close enough to them.
So, the cameras should be located just at the entrance and exit, but in a case of troubles with laying the cables, more distant cameras have to be equipped with long focal lenses (telephoto lenses). Additionally, the entrance and exit lanes should be as narrow as possible, to reduce the area of observation.
It can be done e.g. by arranging some limiters like concrete or metal posts, putting up a barrier etc. The aim of the solution is to minimize the camera's field of view, which allows for recording even small details.
Other infrastructure of gas station
Even medium-size gas station usually offers shopping, car washing, minor repairs etc. Monitoring of all the places requires similar equipment as for stores.
A typical installation made according to the above guidelines, may consist of:
  • Camera no. 1 - monitors entrance to the station,
  • Camera no. 2 - monitors exit from the station,
  • Camera no. 3 & 4 - monitor the first two pumps,
  • Cameras no. 5 & 6 - monitor another two pumps,
  • Camera no. 7 - monitors cash desk and entrance to the station building,
  • Camera no. 8 - monitors other rooms in the building
  • Next cameras, no. 9 to up to 16 - monitor other important places: parking lot, restaurant, car wash ... - not shown in the diagram.
Example of surveillance system for petrol station.
EQUIPMENT SELECTION
Cameras. Taking into consideration the kind of monitored places and objects (people - their appearance and facial features, vehicles - make, color, registration number), we should apply sensitive color cameras featuring high resolution and control of auto-iris lens. Areas with low lighting levels require to use day/night cameras.
Cameras with Super Wide Dynamic sensor or having HIGH LUM CANCEL function (elimination of overexposed places - they are being blackened) are ideal devices for deployment in all locations where there is a possibility of direct dazzling by headlights of the cars.
A universal camera that fulfills all that requirements is Sunell SN-BXC0586DCN(II) M11207. It belongs to the group of the most advanced cameras using Wide Dynamic Pixim image sensors. They are practically insensitive to overexposure and underexposure in fragments of an image, caused both by direct or reflected light, and strong backlight. The image will enable to distinguish details both in bright and dark areas. The camera has many useful functions, including WDR (Wide Dynamic Range), AGC, BLC, ICR and 3D noise reduction.
The DPS technology (Digital Pixel System) sets the exposure for each pixel in the sensor individually, depending on light intensity. So, each pixel is a kind of a separate A/C converter, which allows for well-balanced image, especially in the case of a high contrast and high light intensity.
Lenses. Applications at gas stations require to use lenses with automatic iris (Auto Iris - AI). AI lens automatically adjusts the iris to the light intensity, to pass a similar amount of light to the sensor no matter the illumination conditions are. This way, the camera can operate in extreme illumination conditions (in strong sunlight and poor lighting at night). Additionally, it guaranties that the picture from the camera will not be overexposed by headlights or light reflected from other surfaces (car windows and plating, store windows etc).
Because of small difference in price between fixed and variable focal length lenses, it's worth to apply the latter. They enable quick and easy adjustment of the field of view.
An important component of an outdoor camera is outdoor housing equipped with a heater and thermostat, and a durable bracket. A significant detail is the rainshield, also protecting the lens of the camera from direct sunlight.
SET OF DEVICES AND ACCESSORIES FOR THE TASK
The recommended components for a system compliant with the design guidelines:
Housings
Outdoor Camera Housing: Marathon MH-806/12
  • M5140 Camera bracket TB-647
  • M5415 Housing TH-847 with AC230V heater
  • M1815 Power supply unit TH-647/601 12V/400mA
Cameras:
- universal camera satisfying all requirements for work at gas station
Day/Night Box Camera: Sunell SN-BXC0586DCN(II)(WDR, 690HTVL, Wide Dynamic Pixim, ICR, 0.06 lx)
The compact camera Sunell SN-BXC0586DCN(II) M11207 is equipped with Super Wide Dynamic Pixim Seawolf image sensor and mechanically switching IR filter (ICR). Main features: resistance to overexposure, day and night operation (day/night function), WDR up to 120 dB, 540 TVL.
The image from a "typical" camera
The image from the camera with DPS sensor
- day/night camera
Day/Night Box Camera: u-cam 630 (D-WDR, 650 TVL, Sony Effio-E, ICR, 0.03 lx)
The u-cam 630 M11192 camera uses Sony ExView HAD CCD II sensor and Sony Effio-E DSP. It provides very high video resolution (650 TVL), very good S/N ratio, perfect reproduction of colors.
Good quality of an enlarged part of the image
- camera with increased resolution
Day/Night Box Camera: SN-BXC5930CDN (D-WDR, 650 TVL, Sony Effio-E, ICR, 0.03 lx)
This color day/night camera involves new solutions for processing video in analog CCTV cameras: Sony ExView HAD CCD II with effective resolution of 976(H)x582(V) pixels and Sony Effio-E DSP. It is also equipped with mechanical IR Cut Filter (ICR). The application of Sony Effio-E digital signal processor (DSP) extends the possibilities of image processing and in combination with the advanced image sensor used in the camera allows for horizontal video resolution of 650 TVL. The processor also provides advanced video processing features and OSD, allows the user to define motion detection zones and privacy masks.
Digitally enlarged images from the HiRes camera SN-BXC5930CDN M11209
still ensure high quality indispensable e.g. for monitoring of cash desks.
Compact Outdoor Camera: Sunell SN-IRC4920AJ (day/night, D-WDR, 600 TVL, Sony Effio-E, 0.08 lx, 2.8-10mm, OSD, IR up to 40m)
The Sunell SN-IRC5920AHLDN camera (day/night, D-WDR, 600 TVL, Sony Effio-E, ICR, 0.08 lx, 2.8-10 mm, OSD) is ideal for monitoring of dark parking lots. The integrated IR illuminator employs 42 IR LEDs (850 nm), which are capable of illuminating the scene over a distance up to 40 m. Thanks to the function of intelligent IR lighting, the images are free from overexposure caused by close or reflective objects.

Lenses:
The lens covers a large range of focal length (2.8-12 mm), which enables quick and easy adjustment of the field of view of the camera. As an example, with 1/3" sensor the viewing angle can be varied from ca 82o to ca 23o.
CCTV Lens: JENSEN 5-100 mm DC F1.6
It is an example of AI lens (DC control) with extremely wide range of focal length (5-100 mm). The feature enables quick and easy adjustment of the field of view of the camera. As an example, with 1/3" sensor the viewing angle can be varied from ca 55o to ca 2.7o.
A broader choice of lenses with automatic iris is available here.
VIDEO RECORDING
Another step in designing a CCTV system is selecting devices for live monitoring, recording and playing back the recorded video from the cameras.
Choosing a DVR, the user and installer should take into account:
  • maximum (prospective) number of channels (cameras),
  • recording speed - important for the cameras located at the entry and the exit of the station,
  • recording resolution - important for the identification of people and license numbers of vehicles,
  • ability to define user accounts with multiple access levels,
  • protection of selected recordings against overwriting,
  • recording triggered by motion detection and external signals provided to alarm inputs,
  • possibility of archiving via USB interface,
  • type of video output to the monitor (the best choice is HDMI),
  • network operation,
  • easy access to recordings,
  • support for multiple hard drives - essential for a large archive of recordings,
  • type of compression method - H.264 significantly reduces disk space usage.
Very important feature of the DVR is the recording speed at the desired image resolution. The information in data sheets may be misleading (e.g. 4CIF resolution may apply to the recording speed of 4 fps, insufficient for the surveillance purpose, whereas 25 fps is available only in CIF resolution).
MONITORS
It's worth to pay attention to selecting monitor with a suitable diagonal. If the monitor is to be used sporadically, only for viewing recorded video, the sufficient diagonal is 12"-15". In the case of live monitoring, the minimum size is 19". The video input of the monitor has to be compatible with output of the DVR (in the case of several outputs the monitor should use the highest standard available).
Professional CCTV Monitor: SAMSUNG SMT-1922P (19
Professional CCTV monitor SAMSUNG SMT-1922P M3019 (19")
ACCESSORIES
The important function of any video monitoring system is prevention - its mere presence dramatically lowers the probability of a crime. In less important places it is often sufficient to install dummy cameras. Such cameras installed in standard enclosures cannot be easily identified by the public.
Cameras are usually integrated into the architecture of an object, so the existence of the video surveillance system can be emphasized by information boards, stickers etc.
Video Surveillance Signs: UWAGA OBIEKT MONITOROWANY (PL)
An example of a warning sticker
IP CCTV SYSTEMS - UNLIMITED POSSIBILITIES
The cameras mounted at gas stations are usually located far from the pumps. Due to limited resolution of analog cameras, they have to be equipped with long focal lenses, with narrow viewing angles. Depending on the size of a station, it is necessary to use even tens of cameras. The whole area should be also monitored by additional cameras showing the areas not covered by the narrow-angled devices, to provide general information on the movement of people and vehicles.
An alternative to conventional analog CCTV system is an IP video surveillance solution. The number of cameras can be significantly reduced, due to the application of megapixel devices. For example, the 2MP Pixord P600 K1532 camera has a 5x higher resolution than analog CCTV camera, so it can cover 5x greater area, providing images at the same level of detail.
IP technology requires a completely different concept of CCTV systems. The network is based on UTP cables that can also be used for powering IP cameras supporting PoE technology. Each of the cameras is an independent network device, and they all are integrated into one network via switches and routers.
The recording of the video streams from the cameras can be performed on a PC with suitable software, e.g. Digifort or NUUO. A good alternative to such a solution may be network video recorders (NVR): NUUO NV-4108 K4108 or NV-4116 K4116. The undoubted advantage of IP video surveillance is the fact that the recording does not have to be done on the spot. The digital video data transmitted over the Internet can be accessed in any location, so there is no need for a typical motoring center. It is especially important when there are no good conditions for such a place in the location of the monitoring system.
Network Video Recorder: NUUO NV-4160S (16ch/120fps/1.3MP)
Network Video Recorder: NUUO NV-4160 (16ch/120fps/1.3MP)
IP CCTV software provides much more powerful tools for image analysis. It is worth to mention the additional modules of Digifort software:
Megapixel cameras, due to sensors with a much higher resolution, have to be equipped with megapixel lenses. A measure of lens resolution is the number of line pairs that can be distinguished in one millimeter. This parameter is closely related to the ability of the lens to provide image detail. The lenses for VGA cameras feature about 30 lp/mm, whereas megapixel lenses should guarantee at least 60 lp/mm.
An interesting solution for those who already use an analog monitoring system but want to modernize it, is the hybrid system. It involves the simultaneous use of IP and analog cameras. The thoughtful placement of observation points allows for achieving maximum benefit from new megapixel cameras, while the existing part of the system can still perform the monitoring tasks. This ensures both high performance of the whole system and lower costs of implementation of the modern technology, due to a limited number of the new cameras.
Hikvision DVRs and cameras have been specially designed for such systems, to provide highly efficient and cost-effective solutions. Both the DVRs and IP cameras are managed by uniform iVMS software. Additionally, there are applications that can record and stream the data in the network. The offer includes a wide range of DVRs and IP cameras.
Network applications for security systems and remote monitoring: iVMS4000, NVR Server, Stream Media Server - powerful and free
iVMS playback window
Surveys find that round-the-clock video monitoring and recording at gas stations practically eliminates muggings, damages to pumps, toilets etc., drive-off thefts. The stations have indeed become "no smoking area", at last. The owners have noticed an increased number of customers in station bars/restaurants. Simply the customers are not afraid to park their cars on monitored parking lots.
CONCLUSION

Summing up, application of video surveillance system significantly increases security at every gas station. The mere presence of cameras and "Monitored area" signs has a psychological influence on potential perpetrators, as well as disciplines the staff.