How to convert an image to FFT mask?

Python
3

maybe the following code worth to try if you still trying to solve your previous question.

import cv2
import numpy as np

img = cv2.imread('d:/test/pt4.png', cv2.IMREAD_GRAYSCALE) # load an image as GRAYSCALE

ed = cv2.ximgproc.createEdgeDrawing()
ed.detectEdges(img)
grad_img = np.float32(img)

grad_img = ed.getGradientImage()

cv2.imshow("",grad_img*255)
cv2.waitKey()

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