Ubuntu18.04-python2 installs the opencv4.1 version and replaces the low version of opencv that comes with ROS

Software Environment

• Ubuntu 18.04 system
• ROS melodic

View the CV2 location of the default installation of ROS

Change the name instead of cv2, just ok:

Check to remove

It can be found that there is also a cv2 so file, so we need to remove this as well.

Change the name, in case you need to use it in the future, it can be easily restored:

sudo mv /usr/lib/python2.7/dist-packages/cv2.x86_64-linux-gnu.so /usr/lib/python2.7/dist-packages/cv2.x86_64-linux-gnu.so.bak

It can be seen that there is no cv2 library now.

Install high version opencv-python

Installing opencv-python directly always reports an error inexplicably:

problem solved

The installed opencv-python version is too high, python2 does not support, just download the lower version:

 pip install opencv-python==4.1.1.26 

Successful installation!

Reference article:

• 报错解决：WARNING: The directory ‘/Users/USERNAME/Library/Caches/pip‘ or its parent directory is not owned
• pip2 python2.7 installation opencv-python cv2 possible solutions to problems encountered skbuild list(pattern)