peak.py

#!/usr/bin/env python3

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

imagename = sys.argv[1]
imgcol = cv.imread(imagename)

# Load as black/white for the highpass, 'good enough'
img = cv.imread(imagename, 0)
laplacian = cv.Laplacian(img,cv.CV_64F)
sobelx = cv.Sobel(img,cv.CV_64F,1,0,ksize=5)
sobely = cv.Sobel(img,cv.CV_64F,0,1,ksize=5)

print(np.size(img))
height = len(img)
width = len(img[0])
print(f"{width}x{height}")

for x in range(width):
	for y in range(height):
		# You can try laplacian, sobelx or sobely here:
		# The 30 is a random threshold value. 
		if(laplacian[y, x] > 30):
			imgcol[y, x] = (0, 0, 255)


cv.imshow("Fokus Peak", imgcol)

cv.waitKey(0)
cv.destroyAllWindows()