global area image = cv2.cvtColor(img, cv2.COLOR_BGR2GRAY) blur = cv2.GaussianBlur(image,( 5 , 5 ), 0 ) ret3,th3 = cv2.threshold(blur, 0 , 255 ,cv2.THRESH_BINARY+ cv2.THRESH_OTSU) height, width = th3.shape for i in range(height): for j in range(width): if th3[i, j] == 255 : area += 1 return area