Building and Installing openCV (with python binding). Official instruction is here

1. svn checkout (version 2.3, developer version)
   • https://code.ros.org/svn/opencv/branches/2.3
2. cd openCV
3. makedir build
4. cd build
5. cmake-gui
   • configure python.exe path correctly
   • turn off CUDA option
   • do several times of “configure” untill all is OK.
6. mingw32-make 2>&1 | tee build.log
   • … takes some while
7. mingw32-make install 2>&1 | tee install.log
8. post installation
   • set system path to <openCV>/install/bin
   • set pthon path to <openCV>/install/Python2.*/Lib/site-packages
     • above did not work, so copied files under site-packages/to c:\Python26\Lib\site-packages\