1. Create a virtualenv, mkvirtualenv lookup

2. install opencv on mac via homebrew

brew tap homebrew/science
brew install opencv
cd ~/.virtualenvs/lookup/lib/python2.7/site-packages
ln -s /usr/local/Cellar/opencv/{VERSION_NUMBER}/lib/python2.7/site-packages/cv.py cv.py
ln -s /usr/local/Cellar/opencv/{VERSION_NUMBER}/lib/python2.7/site-packages/cv2.so cv2.so

i.e.

cd ~/.virtualenvs/lookup/lib/python2.7/site-packages
ln -s /usr/local/Cellar/opencv/2.4.12_2/lib/python2.7/site-packages/cv.py cv.py
ln -s /usr/local/Cellar/opencv/2.4.12_2/lib/python2.7/site-packages/cv2.so cv2.so

1. Test see it works or not.

workon lookup
python
import cv2

Reference

https://gist.github.com/stilist/cd7fdfabbf9ec5ed89b7