一种基于数学形态学和投影的车牌定位方法

Vehicle plate location method based on mathematical morphology and projection

车牌定位是车牌识别系统的关键步骤,定位的准确与否直接影响车牌识别的结果。为了能在复杂背景和不同光照条件下快速、准确定位车牌位置,本文根据车牌及拍摄效果等特点及因素,提出了一种结合数学形态学和水平、垂直投影法的定位方法。首先对图像进行预处理,利用数学形态学将预处理过的图像进行处理,滤去一部分伪车牌区域,然后利用水平和垂直扫描进一步精确定位车牌,最后结合车牌的先验知识最终确定车牌区域。实验结果表明,该方法定位率高,速度快,具有良好的鲁棒性。

Vehicle license plate location is the key part of automatic vehicle plate recognition system, the accuracy will influence the plate recognition result. An algorithm for license plate location of mathematical morphology and projection is proposed according to the characterristics of vehicle license plate and the factor of shooting effect in order to obtain location of vehicle plate quickly and accurately under complicated background and different illumination condition. At first, image preprocessing is adopted, in order to filter the part of false plate region, we use the method of mathematical morphology, later, projection and the ratio of the length and width can be used to determine the specific location of license plate. At last, we will determine the final location based on prior experience of license plate. The results indicate that the rate of location is higher, with a good speed and robust.