Common Problems and General Treatment Methods in License Plate Recognition Engineering Debugging - T

Common problems and general processing methods in the commissioning of license plate recognition project scenario 1: the license plate recognition system at the entrance of an underground parking lot, which originally adopted the capture mode of a single video unit. During commissioning, it is found that the recognition rate of the license plate at the entrance is low, and the capture positions of vehicles vary greatly because the equipment is installed at the end of the downhill of the parking lot. Solution: add a video unit and adopt double capture verification mode, which can improve the license plate recognition rate. In addition, a deceleration belt is installed at the end of the downhill road of the parking lot to reduce the driving speed of the vehicle at the capture position to an ideal range, so as to ensure the effect of license plate capture and recognition. Scenario 2: during the test run of the license plate recognition system at the entrance and exit of an outdoor parking lot, it is found that the recognition rate and recognition effect during the day are ideal, but the recognition rate at night is much lower than that during the day. Solution: through field investigation and data analysis, it is found that there are two main reasons for the obvious decline of night recognition rate. The headlights of the vehicle have an impact on the capture effect of the video unit. To solve this problem, the installation height and position of the video unit are readjusted so that the capture effect is no longer affected by the lights at night; The illumination of the environment is insufficient, resulting in unsatisfactory capture effect. In view of this problem, consider adding fill light source to solve this problem. There are also two schemes for the fill lamp: use the constant light fill lamp to fill the light directly; The snap signal is used to control the flash lamp for instantaneous lighting. Through the analysis of environmental factors and the investigation and statistics of vehicle drivers, the latter is finally adopted as the solution. The problem has been solved as a whole. Scene 3: the entrance and exit of a unit's parking lot is narrow and can intelligently accommodate a car. I want to upgrade the original IC card swiping access system to license plate recognition access system through transformation. Solution: by customizing the logic analysis function of hardware and software, the video unit and management system can have the function of analyzing the direction of passing vehicles in a single entrance and exit. This function can avoid the data error caused by the repeated recognition of the license plate by the video unit when the vehicle passes through the entrance and exit, which affects the normal traffic. In addition, the system adds guidance signs and electronic prompt LED screens, which can make drivers consciously abide by the order and orderly traffic when they meet at the entrance and exit at the same time in peak hours, so as to avoid congestion at the entrance and exit of the parking lot.