Abstract: In order to check the ID information of residents in public places in polices’ convenience, ID card number identification method based on gray scale multi-level is put forward to realize the automatic recognition of the ID card number. The idea of the method is as follows：In the first, it should find the location of the four edges of the ID card in the image. According to the principle that the regions of ID card number in ID card are fixed, the ID card number area can be located. Secondly, it can split a single character of the ID card number using the projection method. Finally, the gray-scale image of a single character using multi-level method is processed to extract mesh feature of the character, and the character by the template matching is recognized. This method not only can identify the number quickly, but also can identify blurred or uneven brightness image accurately.

Key words: ID card, location, gray scale multi-level, character recognition

摘要： 为了方便警察在公共场所核对居民的身份证信息，实现身份证号码的自动识别，提出了一种基于灰度多值化的身份证号码识别方法。该方法的思想是先找到身份证的四条边缘在图像中的位置，根据身份证号码所处区域在身份证中是固定的，可以定位到身份证号码所在区域；采用投影法分割出身份证号码单个字符；将单个字符灰度图像进行多值化处理，提取字符的网格特征，利用模板匹配法识别出字符。该方法不仅能快速地识别出号码，而且对于比较模糊或亮度不均匀的图像也能准确地识别。

关键词: 身份证, 定位, 灰度多值化, 字符识别