By default, the cameras are installed at a height of 6 m above the controlled lane edge. The control zone center is located 20 m from the camera. The camera is tilted at an angle of 18 degrees.
We recommend placing the cameras above the edge of the road, and not above the center. In this case, the horizontal inclination will amount to 4 degrees for the control zone width of 3 m.
By default, the cameras controlling the security site entrances and exits are located at a height of 3 m above the lane edge. The control zone center is then located 11 m from the camera.
After the camera is mounted, the lens focal length should be adjusted to the required viewing distance.
To set up the lens without the Uragan software, do the following:
To set up the camera, do the following:
Set the required shutter speed.
1/1000 sec is enough in most cases.
General parameters of used video cameras are presented in the following table.
Analog and IP-cameras can be in use.
Not less than 520 TVL horizontally.
Only high resolution CCTV camera usage guarantees the recognition rate declared in the technical characteristics of the system.
Illuminance of the monitored area
Not less than 50 lux for cameras with 0.05 lux CCD sensitivity;
At night time, standard auto road illumination devices are sufficient to provide 50 lux illuminance in full compliance with the building regulations.
Automatic amplification adjustment
LOW or MIDDLE depending on the camera
This function must be enabled. Unfortunately, the scene is usually not sufficiently illuminated, thus the image looks too dark in case this function is disabled. Enabling this function amplifies the whole video signal including the CCD noise. The amplification value is chosen for each camera separately.
Auto aperture and auto electronic shutter
The image should be sharp. Sharpness can be achieved by locking the shutter speed (exposure). Locking the speed of the electronic shutter is a very important function.
Black and white image
It is recommended to use black and white cameras unless it is necessary to store color pictures of the vehicle. This is because clolr cameras while having same characteristics have less sensitivity and pictures appear less sharp.
Video stream speed (fps)
See the corresponding module functionality description.
For proper recognition, the plate is to be fully observed and read at least in one frame. For getting the car direction, the plate is to be fully observed and read at least in two frames. The maximum speed of vehicles moving in the control zone is defined for each object and depends on the way of camera installation, what objective is in use, etc. In some frames the plate can be light-struck/darkened/covered depending on the traffic situation, the time of day, etc. To avoid such problems, it is necessary to increase the number of frames in which the plate is observed. It is achieved by the video stream speed-up or decreasing of maximum allowed speed of a car.
The following video camera requirements should be met in order to ensure the recognition of license plate numbers using the Auto-Intellect system.