I do not use calibre to manage the books in my reader (Bookeen's Orizon), so I was wondering if it manages creating the thumbnails in the ".thn" format this reader uses, which is different from the ".t2b" of older devices.
Looking at the
source, it looks like the answer is no, but it wouldn't be much work to add the new format for the Orizon (and maybe the Odyssey, but I don't know if this uses the same thumbnail format).
Creating the thn thumbnail is
as easy as the t2b. I also wrote
a utility to write these thumbnails some time ago.