Is it possible to export presentations, that contain videos, as pdf? (so that the video is still visible as video in the pdf file)
You could try opening the odp with something like 7-zip then edit the content.xml so the href to the movie rather than …/path/to/file.extension it is Video/file.extension
Then create a folder in the odp with 7-zip, call the folder Video, and place any file you have referenced in the content.xml in there. I am still testing this method myself, I’ll let you know how I go once I get home to my Linux laptop and its libre office install.
Edit: Annoyingly that trick works to make your odp portable, but it doesn’t work when you convert that ODP to a pd. Unfortunately this feature doesn’t appear to be available on Impress at the moment. There is this guide, but it doesn’t work for me; http://user.services.openoffice.org/en/forum/viewtopic.php?f=10&t=333
To follow up to @secme’s comment, I don’t believe that LO can export a presentation containing video directly to PDF. You may be able to devise a method of converting an ODP document to a PDF with embedded video, but only using tools external to LO.