Linux下为python3安装opencv

1.到opencv官网https://opencv.org/releases.html下载需要的opencn安装包，如opencv-3.4.2，解压

unzip opencv-3.4.2.zip

2.进入该文件夹

   cd opencv-3.4.2

3.建立文件夹release

 mkdir release

4.安装依赖

   sudo apt-get install build-essential cmake libgtk2.0-dev pkg-config python-dev python-numpy libavcodec-dev libavformat-dev libswscale-dev

5.进入release并编译

   cd release

   cmake -D CMAKE_BUILD_TYPE=RELEASE -D CMAKE_INSTALL_PREFIX=/usr/local ..

6.安装

  sudo make install