It was explained pretty well in the blog: Installing the OpenCV python package is easy, fast and painless as long as you're happy with the default binary. Build

It was explained pretty well in the blog: Installing the OpenCV python package is easy, fast and painless as long as you're happy with the default binary. Building OpenCV from source to get it into a C/C++ program can quickly turn into a multi-hour adventure, if you're not familiar with building sizeable C++ projects.