Can't use SURF, SIFT in OpenCV

Solution 1:

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()
   

Solution 2:

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Most information on this question here is obsolete.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.

Solution 3:

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.

Solution 4:

I think this is far from the "correct" way to do it (the "correct" way on Ubuntu seems to be to stick to a broken and/or outdated OpenCV), but for me building opencv-2.4.6.1 from source brings back cv2.SIFT and cv2.SURF.

Steps:

1. Download opencv-2.4.6.1.tar.gz from opencv.org.

2. Extract the source:

   tar -xf opencv-2.4.6.1.tar.gz -C /tmp
   

3. Configure the source. This will tell OpenCV to install into .opencv-2.4.6.1 in your home directory:

   cmake -D CMAKE_BUILD_TYPE=RELEASE \
         -D BUILD_PYTHON_SUPPORT=ON \
         -D WITH_XINE=ON \
         -D WITH_OPENGL=ON \
         -D WITH_TBB=ON \
         -D BUILD_EXAMPLES=ON \
         -D BUILD_NEW_PYTHON_SUPPORT=ON \
         -D WITH_V4L=ON \
         -D CMAKE_INSTALL_PREFIX=~/.opencv-2.4.6.1 \
         /tmp/opencv-2.4.6.1
   

4. Build and install:

   cd /tmp/opencv-2.4.6.1
   make -j4
   make install
   

5. Set PYTHONPATH (this works in bash, I have no clue about other shells):

   export PYTHONPATH=~/.opencv-2.4.6.1/lib/python2.7/dist-packages
   

Now if I start python and import cv2 (for me, this produces a gnome-keyring warning), I have cv2.SIFT and cv2.SURF available.

Solution 5:

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!