import cv2

import numpy as np

# Start with your noisy 344x344 grayscale image

img = np.random.randint(0, 256, (344, 344), dtype=np.uint8)

# Circle settings

center = (img.shape[1]//2, img.shape[0]//2) # (x, y)

radius = 80 # adjust size here (scale)

# Draw filled black circle

cv2.circle(img, center, radius, color=0, thickness=-1)

cv2.imshow("Image with Circle", img)

cv2.waitKey(0)

cv2.destroyAllWindows()