基于Walsh变换检测指纹方向场的算法

依据可靠、误差较小的方向场诃以准确快速地找到诸如指纹螺旋中心等特征，并且使快速提取指纹图中沟和脊的特征成为可能，为此经过分析比较以往检测纹路方向的算法，根据指纹图的特点邮一种用Ｗａｌｓｈ变换检测纹路方向的算法，该自救不但速度较快，容易实现，而且其计算结果也证明能很好地表示指纹图上纹路方向的和特征，即使指纹图像有所旋转，该算法也能得取确切的方向场。

Directional Field of Fingerprint Detection Based on Walsh Transformation

An approach to detect the directional field of fingerprint was proposed.Depending on a reliable directional field,it can immediately extractsome importantfeatures such as the centerof whorl,ridge and furrow on fingerprint.After compared with some published algorithms,an algorithm to detect the direc- tional field of fingerprintbased on Walsh transformation was proposed.The algorithm is not only easy but also fast to be implemented.The experimental results show that it is possible to representthe directional field of fingerprintand extractthe desired features.Even though there is some degrees of fingerprintrota- tion,the algorithm still demonstrates reasonable performance.