Linux下OpenCV，出現錯誤：

ASSERT false in file qasciikey.cpp, line 501

可能是OpenCV的版本有問題，需要重新安裝一下：

pip install -i //pypi.tuna.tsinghua.edu.cn/simple opencv-python

pip install -i //pypi.tuna.tsinghua.edu.cn/simple opencv-contrib-python

如果出現提示：

Could not install packages due to an EnvironmentError: [Errno 13] Permission denied: '/anaconda3/lib/python3.7/site-packages/opencv_contrib_python-4.1.0.25.dist-info' Consider using the --user option or check the permissions.

表示需要使用--user：

pip install --user -i //pypi.tuna.tsinghua.edu.cn/simple opencv-contrib-python