车牌定位：
License plate location:
车牌定位的准确与否直接决定后面的字符分割和识别效果，是影响整个车牌识别率的重要因素。
The accuracy of license plate location directly determines the character segmentation and recognition effect, which is an important factor affecting the whole license plate recognition rate.
车牌定位算法的好坏，由车牌检出率来评估，目前市面上优秀的车牌识别系统，检出率能达到99%以上。
The quality of license plate location algorithm is evaluated by the detection rate of license plate. At present, the detection rate of excellent license plate recognition system on the market can reach more than 99%.
其核心是利用车牌区域的纹理特性，进行车牌定位，常用的车牌检测算法包括：利用梯度信息投影统计；利用小波变换作分割；车牌区域扫描连线算法；利用区域特性训练分类器的方法等。这些算法各有利弊，如何从复杂场景中提取出稳定可靠的车牌区域是一个难点。
Its core is to use the texture characteristics of the license plate area to locate the license plate. The commonly used license plate detection algorithms include: using gradient information projection statistics; using wavelet transform for segmentation; license plate area scanning algorithm; using regional characteristics to train the classifier. These algorithms have their own advantages and disadvantages. How to extract stable and reliable license plate area from complex scenes is a difficult problem.