print 'a'

import cv2

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

img1 = cv2.imread('test_frames/00100.png',0)          # queryImage
img2 = cv2.imread('test_frames/00080.png',0) # trainImage

# Initiate SIFT detector
sift = cv2.xfeatures2d.SIFT_create()

# find the keypoints and descriptors with SIFT
kp1, des1 = sift.detectAndCompute(img1,None)
kp2, des2 = sift.detectAndCompute(img2,None)

# BFMatcher with default params
bf = cv2.BFMatcher()
matches = bf.knnMatch(des1,des2, k=2)

# Apply ratio test
good = []
for m,n in matches:
    good.append([m])

# cv2.drawMatchesKnn expects list of lists as matches.
img3 = cv2.drawMatchesKnn(img1,kp1,img2,kp2,good,None,flags=2)

plt.imshow(img3),plt.show()

cv2.xfeatures2d.

BriefDescriptorExtractor_create