https://www.pyimagesearch.com/2017/10/09/optimizing-opencv-on-the-raspberry-pi/ https://developers.google.com/machine-learning/crash-course/descending-into-ml/video-lecture https://www.superdatascience.com/blogs/opencv-face-recognition https://github.com/trekhleb/homemade-machine-learning?utm_medium=email&utm_source=topic+optin&utm_campaign=awareness&utm_content=20190622+prog+nl&mkt_tok=eyJpIjoiTVRreFpETmxNbU14TVRSaSIsInQiOiIybmptM3ZDNXFtVkVaMlwvelNSa29vZXBvYVlFaktyeWFDaTRSd0RRT0dWK1wvSDZNVndGMHpsaGthS0Z3aHlCU1RRZHNEUVwvUUViUkxqVEhSWnFxOXk0VEtKRXRZdzNtQkQzT1Uzd0h2cWFUNmtKaHdQQ0ZKeEZwZTA1SUpHR2o2RCJ9