指纹图像增强，gabor滤波器，包括形态学分割，形态学细化，加窗短时傅里叶变换增强，方向图估计及平滑，纹线频率估计及平滑-Fingerprint image enhancement, gabor filters, normalization, equalization, morphological segmentation, morphological thinning, windowed short time Fourier transform enhanced estimates and smooth pattern, ridge frequency estimation and smoothing