Embedded videos not working in LibreOffice Impress

Good morning.

I’m writing this post as today I received an Impress file with an embedded video and, after opening the slide that contains it, I noticed a brief hang (likely due to the media trying to load) before seeing the program render the “preview” of the video without the media player UI on top of it, making it impossible to play.

I then tried to do the same operation launching LibreOffice from the command line, and it logged the following errors:

(soffice:92268): GLib-GObject-CRITICAL **: 11:17:43.468: g_object_set: assertion 'G_IS_OBJECT (object)' failed
(soffice:92268): GLib-GObject-CRITICAL **: 11:17:43.468: g_object_set: assertion 'G_IS_OBJECT (object)' failed
(soffice:92268): GStreamer-CRITICAL **: 11:17:43.468: gst_element_get_bus: assertion 'GST_IS_ELEMENT (element)' failed
(soffice:92268): GStreamer-CRITICAL **: 11:17:43.468: gst_bus_add_watch_full: assertion 'GST_IS_BUS (bus)' failed
(soffice:92268): GStreamer-CRITICAL **: 11:17:43.468: gst_bus_set_sync_handler: assertion 'GST_IS_BUS (bus)' failed
(soffice:92268): GLib-GObject-CRITICAL **: 11:17:43.468: g_object_unref: assertion 'G_IS_OBJECT (object)' failed
(soffice:92268): GStreamer-CRITICAL **: 11:17:43.468: gst_element_set_state: assertion 'GST_IS_ELEMENT (element)' failed
(soffice:92268): GLib-CRITICAL **: 11:17:56.550: g_source_remove: assertion 'tag > 0' failed

Searching for them online suggested that there was some error while linking with the GStreamer libraries, but since they are (at least apparently) correctly imported in the LibreOffice derivation and no one else (to my knowledge based on searches in the Nixpkgs repo and this Discourse) reported this issue before I don’t understand whether this is a bug or a problem in my system configuration.

I therefore wanted to ask if anyone else already experienced a similar problem in the past and, in case, if they can share some suggestion on how to troubleshoot it.

Many thanks in advance!

I have the same problem.
As a workaround, I found that converting the video to a different format and then embedding that in the presentation worked:

nix run nixpkgs#ffmpeg -- -i input.mp4 -c:a libvorbis output.ogg

No idea what the actual problem is.

Thanks for your message.

Unfortunately, in my case converting the video to ogg (or to any of the formats marked as “tested” in the Document Foundation wiki) doesn’t solve the problem. Maybe the issue depends on the video itself too…