关键词: 阴影特征, 车牌定位, 定位算法, 数学形态学

Abstract: A new method based on the grads feature of the shadow which showed the candidate vehicle regions and then excluded error license plate area by license plate prior knowledge was proposed． According to the type and proportion of our license plate features it will get a smaller initial partition plate area． Then Soble operator was used for edge detection． Finally it will fast get accurate positioning by mathematical morphology． The results show that the method provides a robust approach， which can effectively detect the front vehicles in complex traffic circumstances in real time．

Key words: shadow feature, license plate location, location algorithm, mathematical morphology