环境
Win10(64bit)+Anaconda3(Python 3.7.3)
下载opencv+contrib
https://www.lfd.uci.edu/~gohlke/pythonlibs/
opencv_python‑4.1.2+contrib‑cp37‑cp37m‑win_amd64.whl
执行下面命令安装opencv+contrib
pip install opencv_python‑4.1.2+contrib‑cp37‑cp37m‑win_amd64.whl