问题
I've been trying to follow the opencv installation steps from pyimagesearch.com with virtualenv. Everything works fine except for the packages path: it should be /Users/JLee/Envs/cv/lib/python2.7/site-packages but it's configured as lib/python2.7/site-packages
In Python, import cv2 works well in the global setting but doesn't work in the 'cv' virtual environment.
While following the steps from the site, I first proceeded without installing virtualenv, then realized I haven't installed it so I installed it later and followed the steps again. Could this be a problem?
Python 2:
-- Interpreter: /Users/JLee/Envs/cv/bin/python2.7 (ver 2.7.10)
-- Libraries: /usr/lib/libpython2.7.dylib (ver 2.7.10)
-- numpy: /Users/JLee/Envs/cv/lib/python2.7/site-packages/numpy/core/include (ver 1.11.1)
-- packages path: lib/python2.7/site-packages
This is the code for cmake to configure the build:
cmake -D CMAKE_BUILD_TYPE=RELEASE
-D CMAKE_INSTALL_PREFIX=/usr/local \
-D PYTHON2_PACKAGES_PATH=/Users/JLee/Envs/cv/lib/python2.7/site-packages \
-D PYTHON2_LIBRARY=/usr/local/Cellar/python/2.7.11/Frameworks/Python.framework/Versions/2.7/bin \
-D PYTHON2_INCLUDE_DIR=/usr/local/Frameworks/Python.framework/Headers \
-D INSTALL_C_EXAMPLES=OFF -D INSTALL_PYTHON_EXAMPLES=ON \ -D BUILD_EXAMPLES=ON \
-D OPENCV_EXTRA_MODULES_PATH=/Users/JLee/Developer/opencv_project/opencv_contrib/modules ..
Thanks for the help in advance!
回答1:
For some reason it looks like CMake didn't automatically determine your site-packages directory for your virtual environment. That's not an issue though, because all you need to do is sym-link in the cv2.so file.
Find your cv2.so file on disk (based on your output, it seems to be in lib/python2.7/site-packages) and then sym-link into your Python virtual environment site-packages directory. From there, everything will work as expected.
来源：https://stackoverflow.com/questions/38500617/wrong-python-packages-path-for-opencv-cmake-installation