import cv2
import numpy as np
from matplotlib import pyplot as plt

img = cv2.imread('img/fuliye.png',0)
f = np.fft.fft2(img)
fshift = np.fft.fftshift(f)
magnitude_spectrum = 20*np.log(np.abs(fshift))

plt.subplot(121),plt.imshow(img,cmap = 'gray')
plt.title('Input Image'),plt.xticks([]),plt.yticks([])
plt.subplot(122),plt.imshow(magnitude_spectrum,cmap = 'gray')
plt.title('Magnitude Spectrum'),plt.xticks([]),plt.yticks([])
plt.show()



#傅立叶变换--OK numpy