import cv2

import numpy as np

import matplotlib.pyplot as plt

img = cv2.imread('opencv-python-foreground-extraction-tut    orial.jpg')

mask = np.zeros(img.shape[:2],np.uint8)

#指定背景和前景模型

bgdModel = np.zeros((1,65),np.float64)

fgdModel = np.zeros((1,65),np.float64)

#需要根据实际改变

rect=(161,79,150,150)

#grab and  cut a certain region

cv2.grabCut(img,mask,rect,bgdModel,fgdModel,5,cv2.GC_INIT    _WITH_RECT)

mask2 = np.where((mask==2)|(mask==0),0,1).astype('uint8')

img=img*mask2[:,:,np.newaxis]

plt.imshow(img)

plt.colorbar()

plt.show()