Ubuntu 或者 Debian 系统显示窗口的时候遇到了这个问题
error: (-2:Unspecified error) The function is not implemented. Rebuild the library with Windows, GTK+ 2.x or Carbon support. If you are on Ubuntu or Debian, install libgtk2.0-dev and pkg-config, then re-run cmake or configure script in function ‘cvNamedWindow’
解决办法：
需要先安装gtk2.0库，再安装opencv
1、apt-getinstall install libgtk2.0-dev
2、安装成功之后，重新运行cmake对opencv的源码进行编译，安装
参考链接：
https://blog.csdn.net/u010632165/article/details/81431030
https://blog.csdn.net/youlinhuanyan/article/details/104109599
