You must install and configure the cameras in such a way that the following requirements are met:
| Type of requirements | Purpose | Requirements for the video image from the camera that is used for detection |
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| Basic requirements | To ensure the recognition of state license plates and vehicles | Camera | - Minimum resolution is 1280*720, recommended resolution is 1920*1080 and more
- Video codec: MJPEG minimum, H.264 or H.265 are recommended, preferably uncompressed
- Bitrate: depends on the frame (license plate must be readable)
- Minimum frame rate: at least five FPS at speed up to 20 km/h (Slow mode), from 20 FPS at speed over 20 km/h (Fast mode)
- Maximum horizontal angle is 30°, recommended angle is 0°
- Maximum vertical angle is 45°, recommended angle is 20°
- Maximum camera rotation angle is 20°, recommended angle is 0°
- In order to recognize state license plates on high-speed roads, the camera must have the Global Shutter mode
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| Lighting | - Illuminated control area. We recommend using conventional spotlights and/or cameras with IR illumination for additional illumination
- Expected image contrast: the contrast difference between characters of the license plate and the background must be at least 20 units with the image brightness scale from 0 to 255
- During daytime and nighttime, we recommend selecting the values of the light sensitivity (ISO) parameter separately with the minimum exposure time (maximum shutter speed)
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| Scene and camera angle | - We recommend installing a camera in such a way that various objects that block the vehicle during its recognition are not in the frame. For example, a barrier or fence
- The state license plate must be readable
- Height of characters (letters and digits) on the state license plates is at least 10px and not more than 60px. Preferably 20px or more
- Width of the dashboard: minimum 80 pixels, recommended 100 pixels
- Thickness of the character line: minimum 1 pixel, recommended 2 pixels
- Vehicles during the passage must be completely within the camera FOV for at least five frames
- The size of the vehicle's bounding rectangle:
- Minimum: height/width is at least 150px and at least 15% of the frame height/width. Recommended: 250px/30%.
- Maximum: height/width isn't limited, but no more than 80% of the height/width of the frame
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| Object images | - To avoid blurring of the image, you must set the camera to a slow shutter speed. We recommend keeping the shutter speed at no more than three ms. The exact value depends on the camera angle and vehicle speed
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| Additional requirements | To determine the driving direction of the vehicle | - Camera installation height is at least three meters
- Angle between camera and road direction is not more than 30°
- Minimum camera tilt
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