Building OpenCV 3.1.0 on macOS

Clone the OpenCV and OpenCV_Contrib repos and checkout release 3.1.0:

git clone https://github.com/opencv/opencv.git
git clone https://github.com/opencv/opencv_contrib.git
cd opencv && git checkout 3.1.0 && cd ..
cd opencv_contrib && git checkout 3.1.0 && cd ..

Create a build directory, configure and build the project:

mkdir opencv_build && cd opencv_build
cmake -D CMAKE_BUILD_TYPE=Release -D APPLE_FRAMEWORK=ON
-D CMAKE_INSTALL_PREFIX=/usr/local -D WITH_CUDA=OFF -D OPENCV_EXTRA_MODULES_PATH=../opencv_contrib/modules ../opencv/
make -j7 # runs 7 jobs in parallel
cd ..

Copy the contrib modules into the OpenCV project:

cp -ri opencv_contrib/modules opencv/modules

To build an iOS framework:

python opencv/platforms/ios/build_framework.py ios

Similarly, to build the macOS framework:

python opencv/platforms/osx/build_framework.py osx