Using Sift (or An Alternative) In Python Opencv 4.2.0 (in 2020)

I am trying to use SIFT for feature detection with Python, but it is no longer part of OpenCV or OpenCV contrib. With OpenCV opencv-contrib-python (both versions 4.2.0.34, the late

Solution 1:

The patent for SIFT expired this Mar 2020. But the opencv might not be updated by moving the SIFT to free open source collection.

See this issue: https://github.com/skvark/opencv-python/issues/126

To rebuild with the non-free components:

git clone --recursive https://github.com/skvark/opencv-python.git
cd opencv-python
export CMAKE_ARGS="-DOPENCV_ENABLE_NONFREE=ON"
python setup.py bdist_wheel

Solution 2:

From the issue: to rebuild with the non-free components:

git clone --recursive https://github.com/skvark/opencv-python.git
cd opencv-python
export CMAKE_ARGS="-DOPENCV_ENABLE_NONFREE=ON"
python setup.py bdist_wheel