Help and Advice on installing your ANPR cameras :

In order to get the best from your ANPR (LPR) Bolt-On licence you need to make sure your camera is optimised for this task. Although your new ANPR software can cope with a wide range of angles and varying image quality it's always best to position the camera to minimise the workload of the ANPR engine software.

Our key tips are:

Reduce the number of angles between the camera and the licence plate. Where possible use cameras designed to see number plates clearly, these will typically have higher quality InfraRed LED and have circuitry to cope with headlight suppression. Set the camera exposure to have a minimum shutter speed of 500th of s second but ideally 1/1000th. In low light conditions you will normally only see the number plate in an otherwise black image, the InfraRed will reflect of the number plate, so always read the front of vehicles which are more retroreflective.. The remaining key element is plate size, the number of pixels horizontal and vertical occupied by the plate.

Angles

There are 3 main angles and by keeping these within the recommended maximum limits you should achieve better levels of ANPR Read accuracy.

Tilt: No more than 30 degrees tilt down.

Pan: No more than 30 degrees from direction of traffic flow.

Plate twist: No more than 5 degrees from horizontal

Lighting

If you want your ANPR cameras to work 24/7 you need good lighting, this lighting can be derived from your cameras InfraRed LED.

Because you need to set the camera's shutter speed (to avoid motion blur) the cameras low light performance will be dramatically affected.

Night time images will typically only display the plate in an otherwise black image.

Clear Images

WIth all forms of Video Analytics proper image quality is extremely important. You need to be able to clearly read the vehicle Number Plates with the naked eye. If you cannot see the plates neither can your ANPR software.

Pixel Count: For optimum results your plate should measure at least W 220 px H 44 px. If you take a snapshot from your ANPR camera you can measure the pixels in most common paint packages.

Your Luxriot ANPR software is designed to provide you with excellent read results across a wide range of lighting conditions, the software module must be configured to your individual site installation characteristics. You must consider the speed of traffic, the site lighting as well as other objects within the scene, road markings, signs, gates or barriers all of which may impact on accuracy.

Consider your site, the speed of traffic, the management of tailgating and equally important the countries you need to decode. Country code is important to make sure the ANPR algorithms know what to expect, each country has specific country syntax for number plates, for example a common UK syntax is LLNN_LLL and rules also apply as to which letters and numbers can sequence together, improving the chances of getting the decoding correct. When setting up in the UK, initially just choose GB syntax, get a measure of your system then slowly introduce other commonly seen countries within your system.

As well as setting up the camera your Luxriot ANPR engine will also need configuring. We recommend you read though your installation manual at this time. The sample settings on the left are from a working 2 traffic lane system and 1080P camera. We have adjusted the scope of the minimum and maximum plate size, adjusted the plate rotation slider to 4 degrees, set the plate schema to both (white plates/black letters & black plates/white letters) and most important for initial setup set the country code to GB only, please select your ISO country codes once you have the ANPR (LPR) engine working correctly with UK plates.

LPR search & playback within Luxriot Monitor is described here.