kmeans.py

import numpy as np
import cv2

img = cv2.imread('building.png')
Z = img.reshape((-1,3))

Z = np.float32(Z)

criteria = (cv2.TERM_CRITERIA_EPS + cv2.TERM_CRITERIA_MAX_ITER, 10, 1.0)
K = 3
ret,label,center=cv2.kmeans(Z,K,None,criteria,10,cv2.KMEANS_RANDOM_CENTERS)

center = np.uint8(center)
res = center[label.flatten()]
res2 = res.reshape((img.shape))

cv2.imshow('k=3',res2)
cv2.imwrite('k=3.jpg',res2)

K = 5
ret,label,center=cv2.kmeans(Z,K,None,criteria,10,cv2.KMEANS_RANDOM_CENTERS)

center = np.uint8(center)
res = center[label.flatten()]
res2 = res.reshape((img.shape))

cv2.imshow('k=5',res2)
cv2.imwrite('k=5.jpg',res2)

K = 8
ret,label,center=cv2.kmeans(Z,K,None,criteria,10,cv2.KMEANS_RANDOM_CENTERS)

center = np.uint8(center)
res = center[label.flatten()]
res2 = res.reshape((img.shape))

cv2.imshow('k=8',res2)
cv2.imwrite('k=8.jpg',res2)
cv2.waitKey(0)
cv2.destroyAllWindows()