# thresholds

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

img = cv.imread('img/sudoku.png',0)
#img = cv.medianBlur(img,5)

ret, th1 = cv.threshold(img,127,255,cv.THRESH_BINARY)
th2 = cv.adaptiveThreshold(img,255,cv.ADAPTIVE_THRESH_MEAN_C, cv.THRESH_BINARY, 11,2)
th3 = cv.adaptiveThreshold(img,255,cv.ADAPTIVE_THRESH_GAUSSIAN_C, cv.THRESH_BINARY, 11,2)

titles = ['Original Image', 'Global Thresholding (v = 127)',
			'Adaptative Mean Thresholding', 'Adaptative Gaussian Thresholding']

images = [img, th1, th2, th3]

for i in xrange(4):
	plt.subplot(2,2,i+1), plt.imshow(images[i],'gray')
	plt.title(titles[i])
	plt.xticks([]),plt.yticks([])
plt.show()