How to properly install Python on OSX for use with OpenCV?

Question

I spent the past couple of days trying to get opencv to work with my Python 2.7 install. I kept getting an error saying that opencv module was not found whenever I try "import cv".

I then decided to try installing opencv using Macports, but that didn't work.

Next, I tried Homebrew, but that didn't work either.

Eventually, I discovered I should modify the PYTHONPATH as such: export PYTHONPATH="/usr/local/lib/python2.6/site-packages/:$PYTHONPATH"

My problem is that I didn't find /usr/local/lib/python2.*...etc The folder simply doesn't exist

So my question is this: How do I properly install Python on OS X Snow Leopard for it to work with opencv?

Thanks a lot,

Answer 1

I spent a couple days on this myself. For me, the problem was that that OpenCV installer was not finding the right python installation. It was defaulting to the MacOS-installed version despite the fact that I had upgraded python with homebrew and was using a virtualenv for python. I have collected most of my setup in a gist here: https://gist.github.com/4150916

Use homebrew to get all the dependencies, but then download the OpenCV tarball and compile yourself being sure to specify all the python related configuration options.

Assuming a virtualenv named 'opencv'...

cd OpenCV-2.4.3/
mkdir release
cd release
cmake -D PYTHON_EXECUTABLE=$WORKON_HOME/opencv/bin/python \
 -D PYTHON_PACKAGES_PATH=$WORKON_HOME/opencv/lib/python2.7/site-packages \
 -D INSTALL_PYTHON_EXAMPLES=ON\
 -D PYTHON_INCLUDE_DIR=/usr/local/Cellar/python/2.7.3/Frameworks/Python.framework/Headers\
 -D PYTHON_LIBRARY=/usr/local/Cellar/python/2.7.3/Frameworks/Python.framework/Versions/2.7/lib/libpython2.7.dylib\
..
make -j8
make install