License plate recognition system design and installation requirements

In the industry of intelligent parking lot system, the license plate recognition system is more advanced intelligent charging system, its used for license plate recognition technology, intelligent high, easy to use, good security, was welcomed by the market.
but the license plate recognition system is greatly influenced by the environmental factors, if environmental conditions are not suitable for, will cause the system can not run normally, so we when installing a license plate recognition system, some live environment is the need to test.
the following is a license plate recognition system design and installation requirements: a, engineering test:

1, the standard lens 5 mm;Linear distance (m) and the license plate pixels (p) the relative size of the following:
3.5 m—156 p;4 m & ndash;140 p;5 m & ndash;112 p;5.5 m—105 p;6 m & ndash;96 p;7 m & ndash;82 p.
2, standard lens 4 mm;Linear distance (m) and the license plate pixels (p) the relative size of the following:
2.5 m—156 p;3 m & ndash;140 p;4 m & ndash;112 p;4.5 m—105 p;5 m & ndash;96 p;6 m & ndash;82 p.

2, identify requirements:
the license plate recognition (90-120 pixels), the license plate recognition (120-160 pixels).
full resolution capture trigger to the scene of feeling vehicles, license plate width size (through drawing software frame plate can display pixel size).

3, engineering principles:
best linear distance: capture camera lenses to feeling outside the side of the straight line distance, generally 5 mm lens is about 5 m, 4 mm lens is about 4 m.

4, engineering requirements:
1, constructing the all-in-one, height: standard in 1.5 m - 1.8 m;
2, cameras column: in a way inside of the brake, the brake lever from about 50 cm;Prevent the brake lever to block the camera capture that affect recognition effect;
wiring, network cable, power cord, switch signal lines and meet city (output).
3, inward and outward to position: all-in-one length 0.5 meters, according to the law of hypotenuse (a&sup 2;+ b&sup 2;= c&sup 2)Computing:
1) the 5 mm lens camera should maintain the horizontal distance and the brake lever in 4.3 meters;
if the camera every beyond 0.5 meters high, 0.25 meters should be narrowed;
2) 4 mm lens of the camera lens should be horizontal distance with the brake lever at around 3.2 meters;
if each beyond 0.5 meters high, should be to reduce the 0.25 meters.
4, deceleration zone position: it is mounted at outside of inward and outward to feeling about 1 m, assure follow car car not touch feeling;
in order to avoid the owner followed with car too close, should erect a warm touch, staying in the 3 m.
5, light: the column height of 0.6 m, in a sense to the side within 50 cm to 80 cm (keep the license plate positive fill light), through the shoot on the ground sense coil can be reflected on the license plate, to ensure that the license plate recognition effect.
6, monitor screen (at the bottom of the slope) : try to keep the license plate width and level parallel, not more than 15 degrees.


the system requirements, can lead to the system of the site environment requirements.The problem according to other projects, in particular, I summarized the following:
1, the vehicles into the image capture area as the effect of the camera is the best;
2, install the license plate recognition sites, should have enough linear distance, convenient installation and debugging, the distance can be so calculate (vehicle length + camera best identification distance);
3, avoid 90 & deg;Equipment installation after turning the license plate recognition system;
4, avoid XiaPoChu installed on license plate recognition system;
5, chaotic environment on site installation of the system (pedestrians many, often have pedestrian passage into the vehicle, to cover the plates).
6, avoid road water treatment when it rains severe channel (easy to keep out license plate);