指纹识别的一个应用实例.利用database来存储指纹的特征值与输入的指纹特征值比较找出近似的.-The basic idea is to combine both global and local information of fingerprint. Given a threshold to detect the given fingerprint with the fingerprint in database

边缘特征的提取就是求图像梯度的局部最大值和方向。实际计算中，以微分算子的形式表示，并采用快速卷积函数来实现。常用的算子有微分算子，拉普拉斯算子，Canny算子等。其中Canny边缘检测是一种较新的边缘检测算子，具有较好的边缘检测性能，得到越来越广泛的应用。Canny边缘检测法利用高斯函数的一阶微分，它能在噪声抑制和边缘检测之间取得较好的平衡-Edge feature extraction is to seek the local maximum of image gradient and ori

指纹增强的matlab实现源代码，包含多个matlab函数文件。-ridgesegment.m identifies ridge-like regions of a fingerprint image. It also normalises the intensity values of the image. ridgeorient.m estimates the local orientation of ridges in a fingerprint. plotridgeorient.

This a MATLAB implementation of the SIFT keypoint detector and descr iptor -do_gaussian: generate Gaussian scale space of input image do_diffofg: generate Difference of Gaussian (DoG) scale space do_localmax: local extrema as the potential keyp