python实现二维傅里叶变换代码

以下是Python实现二维傅里叶变换的代码：

import numpy as np
import matplotlib.pyplot as plt
from scipy.fftpack import fft2, ifft2

def fftshift(img_fft):
row, col = img_fft.shape
mid_row = int(row / 2)
mid_col = int(col / 2)
return np.concatenate((np.concatenate((img_fft[mid_row:, :], img_fft[:mid_row, :]), axis=0)[:, mid_col:],\
np.concatenate((img_fft[mid_row:, :], img_fft[:mid_row, :]), axis=0)[:, :mid_col]), axis=1)

img = plt.imread('image.jpg')
gray = np.dot(img[..., :3], [0.299, 0.587, 0.114])
gray_fft = fft2(gray)
gray_shift = fftshift(gray_fft)
plt.imshow(np.log(np.abs(gray_shift)+1), 'gray')
plt.show()