--- title: Definitive Guide to Install OpenCV 3 and its Python 3 bindings date: 2017-03-23 15:10:00 +09:00 --- This article describes how to install OpenCV 3 and its Python 3 bindings on macOS and Ubuntu. ## `pyenv` users beware Make sure to use system python because there is some tricky problem with OpenCV 3 install script. To switch to system python, run `pyenv global system`. # macOS Install OpenCV 3 package from `homebrew/science`, make sure to add `--with-python3` so we'll also get its Python 3 bindings simultaneously. ```bash brew tap homebrew/science brew install opencv3 --with-python3 ``` After installing OpenCV 3, put OpenCV 3 path file as `opencv3.pth` into brewed-`python3` site-packages directory, which indicates where the OpenCV 3 bindings installed. ```bash echo /usr/local/opt/opencv3/lib/python3.6/site-packages >> /usr/local/lib/python3.6/site-packages/opencv3.pth ``` # Ubuntu ```bash git clone https://github.com/opencv/opencv cd opencv git checkout 3.2.0 mkdir build cd build cmake \ -D CMAKE_BUILD_TYPE=RELEASE \ -D CMAKE_INSTALL_PREFIX=/usr/local \ -D WITH_TBB=ON \ -D WITH_EIGEN=ON \ -D BUILD_NEW_PYTHON_SUPPORT=ON \ -D INSTALL_PYTHON_EXAMPLES=ON \ -D WITH_V4L=ON \ -D WITH_FFMPEG=OFF \ -D BUILD_EXAMPLES=OFF \ -D BUILD_TESTS=OFF \ -D BUILD_PERF_TESTS=OFF \ -D BUILD_DOCS=OFF \ -D BUILD_opencv_python2=OFF \ -D BUILD_opencv_python3=ON \ -D BUILD_opencv_video=OFF \ -D BUILD_opencv_videoio=OFF \ -D BUILD_opencv_videostab=OFF \ -D PYTHON_EXECUTABLE=$(which python) \ "$OPENCV_DIR" make -j2 sudo make install pip install opencv-python ``` # Check install ``` python -c "import cv2;print(cv2.__version__)" ``` and you'll got `3.2.0`.