# Why is SURF slower than SIFT when I use features2d to accomplish this two algorithms? **URL:** \ **Category:** Python\ **Tags:** features2d\ **Created:** [March 16, 2022, 8:34am UTC](https://forum.opencv.org/t/why-is-surf-slower-than-sift-when-i-use-features2d-to-accomplish-this-two-algorithms/7968 "2022-03-16T08:34:51Z")\ **Posts on this page:** 5\ **Page:** 1
**Author:** ![li\_fan](https://sea2.discourse-cdn.com/flex020/user_avatar/forum.opencv.org/li_fan/32/4750_2.png) [@li\_fan](https://forum.opencv.org/u/li_fan)\ **Post date:** [March 16, 2022, 8:34am UTC](https://forum.opencv.org/t/why-is-surf-slower-than-sift-when-i-use-features2d-to-accomplish-this-two-algorithms/7968/1 "2022-03-16T08:34:51Z")
Hi! i just met a doubting question…my code is this: ```auto import numpy as np import cv2 import matplotlib.pyplot as plt import time print("debug") img1 = cv2.imread('rubberwhale1.png',0) # queryImage surf = cv2.xfeatures2d_SURF.create() tic = time.time() kp = surf.detect(img1) toc = time.time() print(f'The total time of the SURF is：：' + str(float(toc - tic))) sift = cv2.xfeatures2d_SIFT.create() tic = time.time() kp = sift.detect(img1) toc = time.time() print(f'The total time of the SIFT is：' + str(float(toc - tic))) ``` i run this script,and i get result like this(i tested many types imgs): > The total time of the SURF is：：1.225409984588623 > The total time of the SIFT is：0.03789663314819336 By the way,my opencv-python == 3.4.2.16 opencv-contrib-python== 3.4.2.16. as i know ，surf should be much faster than sift, why am I getting this result? ---
**Author:** ![li\_fan](https://sea2.discourse-cdn.com/flex020/user_avatar/forum.opencv.org/li_fan/32/4750_2.png) [@li\_fan](https://forum.opencv.org/u/li_fan)\ **Post date:** [March 16, 2022, 12:04pm UTC](https://forum.opencv.org/t/why-is-surf-slower-than-sift-when-i-use-features2d-to-accomplish-this-two-algorithms/7968/2 "2022-03-16T12:04:09Z")
who can help me,i will very appreciate he/she! this question confuses me very much:dizzy\_face: ---
**Author:** ![crackwitz](https://sea2.discourse-cdn.com/flex020/user_avatar/forum.opencv.org/crackwitz/32/14_2.png) [@crackwitz](https://forum.opencv.org/u/crackwitz)\ **Post date:** [March 16, 2022, 12:46pm UTC](https://forum.opencv.org/t/why-is-surf-slower-than-sift-when-i-use-features2d-to-accomplish-this-two-algorithms/7968/3 "2022-03-16T12:46:02Z")
reorder your code. 1. initialize both 2. run both once on the data 3. now measure time of multiple runs of each and you might wanna use `time.perf_counter()` for time differences. that is the highest precision clock available. ---
**Author:** ![li\_fan](https://sea2.discourse-cdn.com/flex020/user_avatar/forum.opencv.org/li_fan/32/4750_2.png) [@li\_fan](https://forum.opencv.org/u/li_fan)\ **Post date:** [March 16, 2022, 2:32pm UTC](https://forum.opencv.org/t/why-is-surf-slower-than-sift-when-i-use-features2d-to-accomplish-this-two-algorithms/7968/5 "2022-03-16T14:32:57Z")
Thank u very much!!! you are right,I have verified that SURF is faster than SIFT,although i didn’t see SURF is threes times than SIFT,but i think it’s maybe parameters problem.thank you again! ---
**Author:** ![li\_fan](https://sea2.discourse-cdn.com/flex020/user_avatar/forum.opencv.org/li_fan/32/4750_2.png) [@li\_fan](https://forum.opencv.org/u/li_fan)\ **Post date:** [March 16, 2022, 2:43pm UTC](https://forum.opencv.org/t/why-is-surf-slower-than-sift-when-i-use-features2d-to-accomplish-this-two-algorithms/7968/6 "2022-03-16T14:43:11Z")
With crackwitz’s help,i successed clear up my doubts,this is my code: ```auto import cv2 import time img1 = cv2.imread('lena.jpg',0) # 1.init #surf = cv2.xfeatures2d_SURF.create() #sift = cv2.xfeatures2d_SIFT.create() surf = cv2.xfeatures2d.SURF_create(400) sift = cv2.xfeatures2d.SIFT_create() total_time = 0 experiment_times = 1 for i in range(experiment_times): tic = time.perf_counter() kp = surf.detect(img1) toc = time.perf_counter() total_time +=(toc - tic) print(f'The mean time of the SURF is：：' + str(float(total_time / experiment_times))) total_time = 0 for i in range(experiment_times): tic = time.perf_counter() kp = sift.detect(img1) toc = time.perf_counter() total_time +=(toc - tic) print(f'The mean time of the SIFT is：' + str(float(total_time / experiment_times))) ``` lena.jpg from opencv/sources/samples/data. when experiment\_times = 1,i got: ```auto The mean time of the SURF is：：1.3295887999999998 The mean time of the SIFT is：0.03701199999999982 ``` when experiment\_times = 3,i got: ```auto The mean time of the SURF is：：0.4178568333333334 The mean time of the SIFT is：0.03863946666666666 ``` when experiment\_times = 10,i got: ```auto The mean time of the SURF is：：0.14091486000000003 The mean time of the SIFT is：0.037559639999999915 ``` when experiment\_times = 100,i got: ```auto The mean time of the SURF is：：0.03580691399999997 The mean time of the SIFT is：0.04023345399999998 ``` when experiment\_times = 300,i got: ```auto The mean time of the SURF is：：0.028634289333333295 The mean time of the SIFT is：0.04184386500000007 ``` when experiment\_times = 500,i got: ```auto The mean time of the SURF is：：0.026373681000000048 The mean time of the SIFT is：0.04070335280000003 ``` if i dont sent 400 to SURF\_create,just use :`surf = cv2.xfeatures2d.SURF_create()`,i got: ```auto experiment_times = 1 The mean time of the SURF is：：1.2036111 experiment_times = 3 The mean time of the SURF is：：0.4234273333333333 experiment_times = 10 The mean time of the SURF is：：0.14784130999999998 experiment_times = 100 The mean time of the SURF is：：0.03896763600000006 experiment_times = 300 The mean time of the SURF is：：0.032780147666666676 ``` just writing about the experiment in the hope that it will help others who have doubts 😁