To resolve this error reinstall opencv-python library.
pip uninstall opencv-python
Install opencv-python:
pip install opencv-python VIDEO GUIDE:
Unspecified error-The function is not implemented. Rebuild the library with Windows, GTK+ 2.x or Cocoa support.
I got this following error while running python program "error: (-2:Unspecified error) The function is not implemented. Rebuild the library with Windows, GTK+ 2.x or Cocoa support."