基于连续方向图的指纹智能预处理算法

文中研究了一种利用Sobel算子提取脊线任意方向的方法,并在融入了指纹图像的特性知识后，提出了一任意方向滤波的指纹智能预处理算法，对于不同质量的指纹图像进行方向滤波，取得了较为理想的结果，实验证明该方法可以较为准确地提取出指纹脊线的方向，对噪化的指纹图像具有较好的鲁棒性。

Intelligent preprocessing of fingerprint based on continuous direction extraction

In this paper, a method for extracting ridge in fingerprint images is proposed, then an intelligent Sobel-based algorithm for filtering fingerprint images in arbitrary direction at a filtering template at required direction is given, which can obtain satisfactory results for different quality grades of fingerprints. Experiments show that this method can estimate the direction of ridges of fingerprint in an image more exactly than most of existing methods based on discrete direction, and it is robust against those noisy fingerprints.