https://blog.wongcw.com/2018/10/20/%e7%a7%91%e5%ad%a6%e5%ae%b6%e5%bc%80%e5%8f%91app%ef%bc%9a%e7%94%a8%e5%89%8d%e7%bd%ae%e6%91%84%e5%83%8f%e5%a4%b4%e7%a1%ae%e8%ae%a4%e7%94%a8%e6%88%b7%e6%b3%a8%e6%84%8f%e5%8a%9b%e9%9b%86%e4%b8%ad/
科学家开发APP:用前置摄像头确认用户注意力集中程度