import cv2 
import matplotlib.pyplot as plt
%matplotlib inline

# read images
img1 = cv2.imread('eiffel_2.jpeg')  
img2 = cv2.imread('eiffel_1.jpg') 

img1 = cv2.cvtColor(img1, cv2.COLOR_BGR2GRAY)
img2 = cv2.cvtColor(img2, cv2.COLOR_BGR2GRAY)

#sift
sift = cv2.xfeatures2d.SIFT_create()

keypoints_1, descriptors_1 = sift.detectAndCompute(img1,None)
keypoints_2, descriptors_2 = sift.detectAndCompute(img2,None)

len(keypoints_1), len(keypoints_2)