Cheese will not close once a video is recorded, causes spiked CPU usage.

[sheenobu]

Issue description

Once you take a video with cheese (as webm), a few strange things happen:

• No thumbnails for images or videos will load.
• Cheese will refuse to close without a 'kill/killall .cheese-wrapped'

Errors:

** (cheese:3543): WARNING **: Icon 'application-octet-stream' not present in theme gnome

(cheese:3543): GnomeDesktop-WARNING **: Unable to create loader for mime type application/octet-stream: Unrecognized image file format

(cheese:3543): GnomeDesktop-WARNING **: Error creating thumbnail for file:///home/sheenobu/videos/Webcam/2016-05-28-140931.webm: Unrecognized image file format

** (cheese:3543): WARNING **: could not generate thumbnail for /home/sheenobu/videos/Webcam/2016-05-28-140931.webm (application/octet-stream)

Steps to reproduce

1. Record video in cheese.
2. Close cheese via 'Quit' button OR by closing the window

Check ps aux | grep cheese (cheese will still be running) and taking up
quite a bit of CPU.

Normal behavior is returned once webm file is moved or deleted.

Technical details

Cheese doesn't understand webm yet tries to record as webm. Then every attempt at loading the webm in the preview pane causes an error.

Maybe a dependency issue and we should depend on some webm support library? Or an upstream issue with Cheese itself?

• System: 16.09.1445.e9a8853 (Flounder); 16.03.885.15e7e6e (Emu)
• Nix version: nix-env (Nix) 1.11.4; nix-env (Nix) 1.11.2
• Nixpkgs version: 16.09.1445.e9a8853; 16.03.885.15e7e6e
• Cheese version: 3.20.2; 3.18.1

[sheenobu]

Updated. Still an issue in 16.09.

[dtzWill]

I can reproduce the problems with thumbnails and webm-related issues on 17.03 and master.

It doesn't seem to crash on exit in my testing.

Playing with propagatedUserEnvPkgs gets problems with missing gnome-video-effects to disappear, adding gstreamer bits (like is done in totem or sushi) doesn't seem to be sufficient (I'm no expert here).

Related: #11634 (#247?).

[jtojnar]

I opened an upstream issue: https://bugzilla.gnome.org/show_bug.cgi?id=791120

[jtojnar]

Running cheese with G_MESSAGES_DEBUG=all environment variable revealed missing path to bubblewrap.

(cheese:15438): GnomeDesktop-DEBUG: Failed to launch script: Failed to execute child process “bwrap” (No such file or directory)
(cheese:15438): GnomeDesktop-DEBUG: Thumbnail script ('/nix/store/03b1njbh3p0akk5sqpplknarz6z8pl7l-totem-3.26.0/bin/totem-video-thumbnailer -s %s %u %o') failed for 'file:///home/jtojnar/Videos/Webcam/2017-12-02-053038.webm': Failed to execute child process “bwrap” (No such file or directory)

After patching gnome_desktop, user still needs to have thumbnailers (gdk_pixbuf and totem) installed, for now I have added them as dependencies like I did in #29970.

The infinite loop is still an upstream bug but with thumbnailers, it at least should not appear.