空间域、频域图像增强，包括基本灰度变换，直方图处理，空间平滑、锐化处理，理想、巴特沃斯和高斯滤波器，快速傅立叶变换等-Space domain, frequency domain image enhancement, including basic gray transform, histogram processing, spatial smoothing, sharpening, ideals, Butterworth and Gaussian filters, fast Fourier t