2017-10-06 11:13:05 -0500 marked best answer SIFT Feature matches coordinates Hello, I want to print the detect features keypoints with the FLANN based Matcher Algorithm : http://docs.opencv.org/trunk/dc/dc3/t.... The search works fine and show as the tutorial the keypoints in red(all) and green(good). I want only print the coordinates(x,y) named here ‘kp2’ of the second image(scene) but it doesn’t work. Here is my code : import numpy as np import cv2 from matplotlib import pyplot as plt img1 = cv2.imread('img1.jpg',0) # queryImage img2 = cv2.imread('img2.jpg',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) # FLANN parameters FLANN_INDEX_KDTREE = 1 index_params = dict(algorithm = FLANN_INDEX_KDTREE, trees = 5) search_params = dict(checks=50) # or pass empty dictionary flann = cv2.FlannBasedMatcher(index_params,search_params) matches = flann.knnMatch(des1,des2,k=2) # Need to draw only good matches, so create a mask matchesMask = [[0,0] for i in range(len(matches))] # ratio test as per Lowe's paper for i,(m,n) in enumerate(matches): if m.distance < 0.7*n.distance: matchesMask[i]=[1,0] print(i,kp2[i].pt) draw_params = dict(matchColor = (0,255,0), singlePointColor = (255,0,0), matchesMask = matchesMask, flags = 0) img3 = cv2.drawMatchesKnn(img1,kp1,img2,kp2,matches,None,**draw_params) plt.imshow(img3,),plt.show()  My result : 77 (67.68722534179688, 92.98455047607422) 82 (14.395119667053223, 93.1697998046875) 86 (127.58460235595703, 98.1304931640625) 109 (66.52041625976562, 111.51738739013672) 110 (66.52041625976562, 111.51738739013672) 146 (69.3978500366211, 11.287369728088379)  The number of match keypoints is good but the coordinates are wrong print(i,kp2[i].pt). I checked with the original image. What I did wrong and if yes which lines I have to put to print only the match keypoints coordinates. Thanks for all. 2017-10-06 09:46:29 -0500 commented question SIFT Feature matches coordinates I just find an issue. I change with: # ratio test as per Lowe's paper for i,(m,n) in enumerate(matches): if m.dista 2017-10-06 09:45:26 -0500 commented question SIFT Feature matches coordinates I correct my mistake I change by this: # ratio test as per Lowe's paper for i,(m,n) in enumerate(matches): if m.dis 2017-10-06 08:28:30 -0500 received badge ● Editor (source) 2017-10-06 08:28:30 -0500 edited question SIFT Feature matches coordinates SIFT Feature matches coordinates Hello, I want to print the detect features keypoints with the FLANN based Matcher Algo 2017-10-06 08:27:06 -0500 asked a question SIFT Feature matches coordinates SIFT Feature matches coordinates Hello, I want to print the detect features keypoints with the FLANN based Matcher Algo