Documentation for Auto Intellect 5.5. Documentation for other versions of Intellect is available too.
For recognition it is necessary to make sure that frames with number plates fulfill the following characteristics:
- the camera should be installed permanently (for detailed installation information, see the vendor documentation);
- the symbols height for IP cameras should be not less than 20-30 px, for analog cameras - not less than 14-20 px, the stroke width should be not less than 2 px;
- minimum allowed contrast with evenly dirty number plate should not be less than 10% ) contrast differentiation of symbols to the background is 25 on 256 point scale);
- maximum allowed uneven dirtiness is not more than 12% (ratio of the dirty area of the number plate to its whole area);
- geometrical proportions of the number plate picture should not differ from such proportions of the number plate itself with more than 10%.
Vehicles speed at recognition in the Fast mode stated in this document (up to 300 km/h) is provided using special cameras and frame rate more than 25fps. However, in the Auto-Intellect software, frame rate in the Fast mode is fixed at 25fps, therefore speed of vehicles in the Fast mode is limited to 150 km/h in the Auto-Intellect software.
Basic characteristics of used video cameras are presented in the General requirements for mounting and configuring of cameras section.
Examples of LP images that will be recognized correctly and completely:
To ensure the correct recognition of the LP number, its image should not be:
- unequally lit;
- blurred (due to incorrect shutter speed settings for the speed of the vehicle);
- distorted (due to incorrect placement of the camera);
Any deviation from the above requirements reduces the likelihood of correct number recognition.