[python] Can't use SURF, SIFT in OpenCV

I'm trying a simple thing like

detector = cv2.SIFT()

and get this bad error

detector = cv2.SIFT()
AttributeError: 'module' object has no attribute 'SIFT'

I do not understand that because cv2 is installed.

cv2.__version__ is

$Rev: 4557 $

My system is Ubuntu 12.04.

Maybe someone has got the same problem and could help me.

EDIT:

Long story short, testypypypy.py:

import cv2

detector = cv2.SIFT()

ERROR:

Traceback (most recent call last):
  File "testypypy.py", line 3, in <module>
    detector = cv2.SIFT()
AttributeError: 'module' object has no attribute 'SIFT

If I take SURF it works because SURF is in dir(cv2) but if I also take cv2.BFMatcher() I get the same error... So it's missing and I have to add it but I don't know how.

try this

!pip install opencv-contrib-python==4.4.0.44 sift = cv2.SIFT_create()

This is what worked for me in September 2020:

1. Remove previous versions:

   pip uninstall opencv-python
   pip uninstall opencv-contrib-python
   

2. Install this particular version (3.4.2.16 was no longer available)

   pip install opencv-python==3.4.2.17
   pip install opencv-contrib-python==3.4.2.17
   

3. Create the detectors with:

   import cv2
   sift = cv2.xfeatures2d.SIFT_create()
   surf = cv2.xfeatures2d.SURF_create()
   

The approach suggested by vizzy also works with OpenCV 2.4.8, as when building the non-free package under Ubuntu 14.04 LTS.

This dependency issue may prevent installation of the non-free package:

 libopencv-nonfree2.4 depends on libopencv-ocl2.4; however:
  Package libopencv-ocl2.4 is not installed.

Easily fixable because the missing package can be installed from the ones just built:

dpkg -i libopencv-ocl2.4_2.4.8+dfsg1-2ubuntu1_amd64.deb

After that the install proceeds as explained in vizzy's answer.

As an Anaconda user, I wanted to find one or two appropriate commands to solve the problem. Fortunately, this answer helped. For conda 4.5.11 (use conda -V to check Anaconda version) I have performed next steps:

# Python version does not matter, most likely, check yourself
conda create -n myenv python=3.6     
conda activate myenv
conda install -c menpo opencv

That will install OpenCV 2.4.11. Anaconda's another command conda install -c menpo opencv3 will install OpenCV3, but Python has to be downgraded to 2.7. To install OpenCV3 with Python3 use next (due to the first link):

conda create -n myenv python  
pip install opencv-python==3.4.2.16
pip install opencv-contrib-python==3.4.2.16

Check the SIFT:

conda activate myenv
python
>>> cv2.xfeatures2d.SIFT_create()
<xfeatures2d_SIFT 000002A3478655B0>

1. Install OpenCV-Contrib

2. import cv2 sift = cv2.xfeatures2d.SIFT_create()

3. sift.something()

This is the easy way to install the Contrib.

FYI, as of 3.0.0 SIFT and friends are in a contrib repo located at https://github.com/Itseez/opencv_contrib and are not included with opencv by default.

Install Python opencv

pip install opencv-python

and instead of using ..

cv2.SIFT()

Use

cv2.SIFT_create()

working code using opencv-python below

import cv2
img1 = cv2.imread('yourimg.png',0)
sift = cv2.SIFT_create()
kp1, des1 = sift.detectAndCompute(img1,None) #keypoint and descriptors
...

you can also install "opencv-contrib-python" and use "cv2.xfeatures2d.SIFT_create()" but that is secondary and up to you.. working code using the python package opencv-contrib-python

import cv2
img1 = cv2.imread('yourimg.png',0)
sift = cv2.xfeatures2d.SIFT_create()
kp1, des1 = sift.detectAndCompute(img1,None) #keypoint and descriptors

Thanks

As per June 2020, I suppose this version (pip install -U opencv-contrib-python==3.4.2.16) is still working. so install it and enjoy.

Follow this installation operation

cmake -D CMAKE_BUILD_TYPE=RELEASE -D CMAKE_INSTALL_PREFIX=/usr/local
    -D WITH_TBB=ON -D BUILD_NEW_PYTHON_SUPPORT=ON -D WITH_V4L=ON 
    -D INSTALL_C_EXAMPLES=ON -D INSTALL_PYTHON_EXAMPLES=ON 
    -D BUILD_EXAMPLES=ON -D WITH_QT=ON -D WITH_OPENGL=ON ..

using this command will install library to your /usr/local/lib.

Just change the version of opencv to 3.4.2.16 .Since it is patented it is not available in newer version.

None of the above suggested solutions worked for me. I use Anaconda and found that opencv version 3.3.1 still had Sift enabled. If you want to test in isolated conda environment, try the following inspired from @A.Ametov's answer above

conda create -n testenv opencv=3.3.1     
conda activate testenv

conda activate myenv
python
#Check version of opencv being used
>>> import cv2
>>> cv2.__version__
#Check if Sift is available
>>> cv2.xfeatures2d.SIFT_create()
<xfeatures2d_SIFT 000002A3478655B0>

just change SHIFT to ORB, I think it make occur because of non-relevant version, ORB is efficient and better alternative of SHIFT or SURF.

As I also face same problem when i was used cv2.SHIFT()

ERROR: AttributeError: 'module' object has no attribute 'SIFT'

Now its completely working for me please try this:

ORB = cv2.ORB()

IN opencv3.x SIFT() & SURF() are no longer exist .for this

uninstall all the opencv versions

python -m pip uninstall opencv-python

python -m pip uninstall opencv-contrib-python

after that install opencv-contrib to include sift() and surf() using below given command with python(3.x)

python -m pip install opencv-contrib-python==3.4.2.16

then you can use

sift = cv2.xfeatures2d.SIFT_create()

Change this:

sift = cv2.xfeatures2d.SIFT_create()

By this:

cv2.ORB_create()

There is a pip source that makes this very easy.

1. If you have another version of opencv-python installed use this command to remove it to avoid conflicts:

   pip uninstall opencv-python
   

2. Then install the contrib version with this:

   pip install opencv-contrib-python
   

3. SIFT usage:

   import cv2
   sift = cv2.xfeatures2d.SIFT_create()
   

For recent information on this issue (as of Sept 2015) consult this page.

Most information on this question here is obsolete.

What pyimagesearch is saying is that SURF/SIFT were moved to opencv_contrib because of patent issues.

For installation there is also a nice page that tells you how to install opencv with opencv_contrib and Python support so you get SURF/SIFT.

Notice that the API also changed. Now it's like this:

sift = cv2.xfeatures2d.SIFT_create()

Before I found the above pages, I also suffered quite a bit. But the pages listed do a very good job of helping with installation and explaining what's wrong.

for debian users its 'easy' to create their own libopencv-nonfree package.

i followed the opencv tutorial for python, but in my debian the SIFT and SURF modules were missing. And there is no non-free package available for debian including SIFT and SURF etc.

They were stripped from the package due to license issues....

i never created a package for debian before (adding a new module etc) but i followed some small steps in the debian tutorials and tried and guessed around a bit, and after 1 day, voila... i got working a libopencv-nonfree2.4 deb package and a python module with correct bindings.

(i dont know if i also needed to install the newly built python-opencv package or only the nonfree... i re-installed both and got a working python opencv library with all necessary nonfree modules!)

ok, here it is:

!this is for libopencv 2.4!

!you can do all steps except installing as a normal user!

we need the built essesntials and some tools from debian repository to compile and create a new package:

sudo apt-get install build-essential fakeroot devscripts

create a directory in your home and change to that directory:

cd ~ && mkdir opencv-debian
cd opencv-debian

download the needed packages:

apt-get source libopencv-core2.4

and download all needed dependency packages to build the new opencv

apt-get build-dep libopencv-core2.4

this will download the neeeded sources and create a directory called "opencv-2.4.9.1+dfsg"

change to that directory:

cd opencv-2.4.9.1+dfsg

now you can test if the package will built without modifications by typing:

fakeroot debian/rules binary

this will take a long time! this step should finish without errors you now have a lot of .deb packages in your opencv-debian directory

now we make some modifications to the package definition to let debian buld the nonfree modules and package!

change to the opencv-debian directory and download the correct opencv source.. in my case opencv 2.4.9 or so

i got mine from https://github.com/Itseez/opencv/releases

wget https://codeload.github.com/Itseez/opencv/tar.gz/2.4.9

this will download opencv-2.4.9.tar.gz

extract the archive:

tar -xzvf opencv-2.4.9.tar.gz

this will unpack the original source to a directory called opencv-2.4.9

now copy the nonfree modules from original source to the debian source:

cp -rv opencv-2.4.9/modules/nonfree opencv-2.4.9.1+dfsg/modules/

ok, now we have the source of the nonfree modules, but thats not enough for debian... we need to modify 1 file and create a new one

we have to edit the debian control file and add a new section at end of file: (i use mcedit as an editor here)

mcedit opencv-2.4.9.1+dfsg/debian/control

or use any other editor of your choice

and add this section:

Package: libopencv-nonfree2.4
Architecture: any
Depends: ${shlibs:Depends}, ${misc:Depends}
Description: OpenCV Nonfree Modules like SIFT and SURF
 This package contains nonfree modules for the OpenCV (Open Computer Vision)
 library.
 .
 The Open Computer Vision Library is a collection of algorithms and sample
 code for various computer vision problems. The library is compatible with
 IPL (Intel's Image Processing Library) and, if available, can use IPP
 (Intel's Integrated Performance Primitives) for better performance.
 .
 OpenCV provides low level portable data types and operators, and a set
 of high level functionalities for video acquisition, image processing and
 analysis, structural analysis, motion analysis and object tracking, object
 recognition, camera calibration and 3D reconstruction.

now we create a new file called libopencv-nonfree2.4.install

touch opencv-2.4.9.1+dfsg/debian/libopencv-nonfree2.4.install

and edit:

mcedit opencv-2.4.9.1+dfsg/debian/libopencv-nonfree2.4.install

and add the following content:

usr/lib/*/libopencv_nonfree.so.*

ok, thats it, now create the packages again:

cd opencv-2.4.9.1+dfsg

first a clean up:

fakeroot debian/rules clean

and build:

fakeroot debian/rules binary

et voila... after a while you have a fresh built and a new package libopencv-nonfree2.4.deb!

now install as root:

dpkg -i libopencv-nonfree2.4.deb
dpkg -i python-opencv.deb

and test!

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

img = cv2.imread('test.jpg')
gray = cv2.cvtColor(img,cv2.COLOR_BGR2GRAY)

sift = cv2.SIFT()
kp = sift.detect(gray,None)
img=cv2.drawKeypoints(gray,kp)

corners = cv2.goodFeaturesToTrack(gray,16,0.05,10)
corners = np.int0(corners)

for i in corners:
    x,y = i.ravel()
    cv2.circle(img,(x,y),90,255,3)

plt.imshow(img),plt.show()

have fun!

The following page provides a relatively good guide that requires few corrections : https://cv-tricks.com/how-to/installation-of-opencv-4-1-0-in-windows-10-from-source/

On step 8, when you are choosing generator for the project (tool used for building), don't forget to specify x64 in the second field if you need it. If you don't, you will get LNK1112 error, which is a linker error caused if one module is created with the x64 compiler, and another module is created with the x86 compiler.

Next, when choosing flags in step 9, don't forget to tick the "OPENCV_ENABLE_NONFREE", and set the path for flag "OPENCV_EXTRA_MODULES_PATH" flag. The path must be set to "modules" folder in opencv-contrib-python.

So you need both opencv, and opencv-contrib-python in order to use SIFT and SURF.

You can proceed in this way. It must work for you as well!

Step 1:

virtualenv venv 
source venv/bin/activate

Step 2:

sudo python3 -m pip install opencv-python==3.4.2.16 
sudo python3 -m pip install opencv-contrib-python==3.4.2.16

Step 3:

import cv2
sift = cv2.xfeatures2d.SIFT_create()

Don't use cv2.SIFT() . It will raise an exception.

since I had already compiled opencv when I discovered this problem, all I had to do was (from my opencv build directory):

make opencv_nonfree
sudo make install