此代码基于opencv2.2,实现的功能：在频域中对图像进行低能滤波处理，输出一幅灰度图，一幅傅氏实部图，一幅虚部图-This code is based on opencv2.2, to achieve the function: low frequency domain filtering of image processing, output a grayscale, a real part of Fourier maps, an imaginary figure