对指纹识别系统中指纹图片预处理的修改，增加了图像有效区域的选择，同时在二值化采用了新的 算法。谢谢大家修正。-Of fingerprint identification system fingerprint image pre-processing changes, an increase of the effective image region selection, at the same time Binarization using a new algorithm. Thank you all amendments.