经过车牌定位后所获取的车牌图像不可避免地存在某种程度的倾斜。这种倾斜不仅会给下一步字符分割带来困难，最终也将对车牌识别的正确性造成直接地影响。因此要找到一种方法能够检测车牌图像是否水平以及它倾斜的精确角度。-After the license plate localization for after the license plate image inevitably exists some degree of inclination. This kind of inclined will not only give the next character segmentation difficult, and ultimately will also be on the correctness of the license plate identification caused directly influence. So to find a way to test whether or not the license plate image level and its tilt precise angles.