opencv-python-headless asking for GTK-3

[josubg]

Expected behaviour

Not to install Interface libraries in my server for opencv-python-headless version.

Actual behaviour

I installed the opencv-python-headless version but it appears to require GTK 3 installed in the system

Steps to reproduce

• example code

Install all libraries dependencies except GTK:

pip3 install opencv-python-headless libwebp6
sudo  apt-get install liblapack3 libcblas3 libatlas3-base libwebp6 libtiff5 libjasper1 libilmbase12 
    libopenexr22 libgstreamer1.0-0 libavcodev57 libavformat57 libswscale4 

Try to import :

Import cv2

Error:

Import Error: libgtk-3.so.0: cannot  open shared object file  No such file or directory

• operating system
  Raspbian Stretch Lite Minimal image based on Debian Stretch
  Version:November 2018
  Release date:2018-11-13
  Kernel version:4.14
• architecture (e.g. x86)
  arm
• opencv-python version
  opencv-python-headless

[skvark]

This repository does not generate ARM wheels. Please report the issue to the piwheels repository (I assume that you are using Rasbperry Pi): https://github.com/bennuttall/piwheels