Raspberry Pi Open CV Install - opencv

Question

I installed opencv-python and opencv-python-contrib
after i installed them I realized I wasn't supposed to
How do I uninstall it
Also, which one should I keep, to do facial recongnition with raspberry pi
Import cv2 didn't work when I tried to run a python file, I don't know why it is happening!

Answer 1

If you are using armbian or raspbian, you can uninstall packages with apt:
apt uninstall opencv-python opencv-python-contrib
I suggest that if you want to completely uninstall and remove configuration files use purge:
apt purge opencv-python opencv-python-contrib
and aftter that, you can uninstall packages that came with opencv:
apt autoremove --purge

Answer 2

If you need Extra modules: just keep opencv-python-contrib
Extra modules https://docs.opencv.org/4.x/index.html
pypi.org https://pypi.org/project/opencv-contrib-python/
Installation and Usage
If you have previous/other manually installed (= not installed via pip) version of OpenCV installed (e.g. cv2 module in the root of Python's site-packages), remove it before installation to avoid conflicts.
Make sure that your pip version is up-to-date (19.3 is the minimum supported version): pip install --upgrade pip. Check version with pip -V. For example Linux distributions ship usually with very old pip versions which cause a lot of unexpected problems especially with the manylinux format.
Select the correct package for your environment:
There are four different packages (see options 1, 2, 3 and 4 below) and you should SELECT ONLY ONE OF THEM. Do not install multiple different packages in the same environment. There is no plugin architecture: all the packages use the same namespace (cv2). If you installed multiple different packages in the same environment, uninstall them all with pip uninstall and reinstall only one package.
a. Packages for standard desktop environments (Windows, macOS, almost any GNU/Linux distribution)
Option 1 - Main modules package: pip install opencv-python
Option 2 - Full package (contains both main modules and contrib/extra modules): pip install opencv-contrib-python (check contrib/extra modules listing from OpenCV documentation)
b. Packages for server (headless) environments (such as Docker, cloud environments etc.), no GUI library dependencies
These packages are smaller than the two other packages above because they do not contain any GUI functionality (not compiled with Qt / other GUI components). This means that the packages avoid a heavy dependency chain to X11 libraries and you will have for example smaller Docker images as a result. You should always use these packages if you do not use cv2.imshow et al. or you are using some other package (such as PyQt) than OpenCV to create your GUI.
Option 3 - Headless main modules package: pip install opencv-python-headless
Option 4 - Headless full package (contains both main modules and contrib/extra modules): pip install opencv-contrib-python-headless (check contrib/extra modules listing from OpenCV documentation)