face recognition (Could not connect to display)

[ZouJennie]

I downloaded the package of qt_face_recognition on QTPC from github and when I roslaunch it with command roslaunch qt_face_recognition qt_face_recognition.launch, there is an error:

QXcbConnection:Could not connect to display

[image_view-2] process has died [pid 27683, exit code -6, cmd /opt/ros/kinetic/lib/image_view/image_view image:=/face_recognition/out __name:=image_view __log:=/home/qtrobot/.ros/log/2a0ab0ce-5a1a-11ea-a602-b827ebcff20c/image_view-2.log].

log file: /home/qtrobot/.ros/log/2a0ab0ce-5a1a-11ea-a602-b827ebcff20c/image_view-2*.log```

[qtrobot]

@ZouJennie I imaging you are launching the qt_face_recognition app from SSH terminal, right?

some of the app's has GUI and needs XServer. this means that you can run them either

• via desktop terminal (directly on QTPC desktop, not ssh)
• via X-forwarded terminal (e.g. ssh -X ....)

Please notice that this is neither QTrobot-related issue nor ROS. You need to understand how linux graphic works. :)