Adaptive_thresholding.py

import numpy as np
import cv2
from matplotlib import pyplot as plt
img = cv2.imread("imgs/chapter5/sudoku.png", 0); 
img = cv2.blur(img, (3, 3));


#############################FOCUS################################################
ret,thresh1 = cv2.threshold(img,127,255,cv2.THRESH_BINARY)
thresh2 = cv2.adaptiveThreshold(img,255,cv2.ADAPTIVE_THRESH_MEAN_C, cv2.THRESH_BINARY,11,2)
thresh3 = cv2.adaptiveThreshold(img,255,cv2.ADAPTIVE_THRESH_GAUSSIAN_C, cv2.THRESH_BINARY,11,2)
##################################################################################




f = plt.figure(figsize=(15,15))
f.add_subplot(2, 2, 1).set_title('Original Image');
plt.imshow(img, cmap = "gray")
f.add_subplot(2, 2, 2).set_title('Simple Threshold');
plt.imshow(thresh1, cmap = "gray");
f.add_subplot(2, 2, 3).set_title('ADAPTIVE_THRESH_MEAN_C');
plt.imshow(thresh2, cmap = "gray");
f.add_subplot(2, 2, 4).set_title('ADAPTIVE_THRESH_GAUSSIAN_C');
plt.imshow(thresh3, cmap = "gray");
plt.show();