Unable to show the sample video in built-in panel, "com.canonical.certification::graphics/video_primary" case fail

[baconYao]

Bug Description

No error be thrown but the sample video cannot be shown in built-in panel (w/o external HDMI monitor)

Cert-blocker Test Case

• cert-blocker

To Reproduce

1. Cold boot without the external HDMI monitor
2. Run the "com.canonical.certification::graphics/video_primary" job
3. Observe the sample video be shown in the built-in panel

Expected Result

The sample video should be shown in the built-in panel

Actual Result

1. While using Checkbox, no sample video be shown, but there's an app be opened and closed on the menu bar
2. I can see the sample video be shown in the built-in panel via the following steps

ssh into DUT

Run command: gst-launch-1.0 videotestsrc ! videoconvert ! autovideosink

Environment

• OS: Desktop 26.04
• Checkbox Type: snap
• Checkbox Version

Relevant log output

Additional context

CID: 202605-38787 & 202605-38788

[syncronize-issues-to-jira]

Thank you for reporting your feedback to us!

The internal ticket has been created: https://warthogs.atlassian.net/browse/CHECKBOX-2294.

This message was autogenerated

[tomli380576]

does this pipeline work inside the checkbox shell?
I just tried, this pipeline works. The issue is caused by autovideosink being unable to find the correct sink.

gst-launch-1.0 -v videotestsrc ! videoconvert ! gtkwaylandsink

[tomli380576]

we could add this snippet to use a fixed sink instead of trying to guess the sink

xdg_session_type = os.environ["XDG_SESSION_TYPE"]
if xdg_session_type == 'wayland':
    sink = "waylandsink" # existed since 20.04
elif xdg_session_type == 'x11':
    sink = "ximagesink" # this exists on all versions all the way back to 16.04
else:
    # or use filesink / fakesink
    raise RuntimeError("Not in a graphical session! XDG_SESSION_TYPE is {}".format(xdg_session_type))

[tomli380576]

actually on second thought let's use xvimagesink for a hardware accelerated sink. ximagesink is apparently CPU only