Your code is a little too complex

[JellyDream]

for example，brenner code:
python:
for x in range(0,shape[0]-2):
out += (img[x+2,:]-img[x,:])**2
out = sum(out)

[zjmlovlin]

Sorry, I was used to this way of writing. If it seems complicated, you can try to rewrite it with simple code. I am honored to reply you.