I'd like to generate thumbnails from various "document" file formats such as odt, doc(x) and ppt(x) but also mp4, psd, tiff (and possibly others) from a Python application. As far as I know for each of these formats there is at least one open source application which can generate preview images/thumbnails (e.g. LibreOffice, ffmpeg) or at least extract embedded thumbnails (e.g. imagemagick).
My main problem is that each of these applications/libraries use different command line options so I'm looking for a Python library (or a unified CLI tool) which provides a high-level API to generate a thumbnail with specified dimensions, quality level given a filename and calls the appropriate external tool (ideally including catching exceptions, segfaults and timeouts). Bonus points if it can generate multiple thumbnails if requested (e.g. one per page, page X-Y, every Z seconds but at most N images).
Does anyone know such a library/utility? (Boundary condition: The files may contain sensitive material or might be quite big so this must work without any network communication, using an external web service is not possible.)
If there is no such thing in Python, a locally installable web service would be fine as well.