> Hi,
>
> how can I convert a video file to the .vdr file format? Can I use
> transcode or mencoder for that?
>
> I know there are several tools to convert from .vdr to something else,
> but I want it the other way round and convert "something else" to .vdr
> to watch the video with vdr, later.

Aktually VDR plays any MPEG file renamed to .vdr just fine.
Just rename it (or make a link) to .vdr and put it in a directory following the VDR conventions for a recording (YYYY-MM-DD.HH.MM.50.99).
However the index is missing and the trick modes (search, slow) are not working.
To fix this use "genindex" to generate an index file.