1. College of Mechanical Engineering, Chongqing University of Technology, Chongqing 400050, China
2.The Tenth Research Institute of China Electronic Technology Group Corporation, Sichuan, Chengdu 610036, China
Abstract:In order to detect the front vehicle distance, a monocular imaging system based on CCD was used to collect the vehicle image, and the vehicle distance was measured by detecting the number of pixels in the image.The model including license plate image and vehicle distance information was established by the position and size relationships between object and its image based on the image model of monocular camera.Meanwhile based on the principle of CCD imaging, the model between license plate image and sensor pixels was established.Then the model of ranging detection algorithm was constructed.By building a CCD imaging system, the license plate image of the measured vehicle was acquired.The man-machine interface was designed by using MATLAB, and pre-processings were carried out to improve the image contrast.By matching connected regions and other algorithms, the license plate was located and segmented, and the number of pixels in the horizontal direction of the image was detected.On this basis, the size of vehicle distance was calculated with the principle of small aperture imaging and was displayed on the software platform.Experiments proved that the system can analyze the image of the front vehicle and calculate the distance, the average error of the system is 4% for the distance detection beyond 3 meters.
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