Homebrew

Homebrew is a package manager that allows you to install software. To install Homebrew, follow these Terminal command line instructions:

install homebrew

/usr/bin/ruby -e "$(curl -fsSL https://raw.githubusercontent.com/Homebrew/install/master/install)"

install XCode Command Line Tools

xcode-select --install

Agree if asked to install XCode Command Line Tools.

check homebrew

brew doctor

install graphviz (optional)

brew install graphviz

install opencv

brew tap homebrew/science

Mac Instructions

brew edit opencv

change: -DBUILD_opencv_java=OFF to -DBUILD_opencv_java=ON

brew install --build-from-source opencv