[vdr] Compressing videos more than mpeg2

[Mark Watson]

My VDR box is starting to fill up again - got about 450GB of edited video 
now... Rather than buying another HDD  (or two!) I'm thinking of 
re-compressing some stuff as xvid or mpeg4. I have a large TV so want to 
avoid adding new compression artifacts as much as possible. I also want to 
keep the interlaced format, framerate and different aspect ratios (may be 
more than one per recording). Ideally I also want to make it integrate with 
VDR properly, i.e. play back via the Recordings menu, has summary info etc.

I'm thinking that I'll need to do something like this:
i) Add a script to the reccmds.conf to recompress. I was hoping to use 
transcode or mencoder libraries. However neither of these seem to support 
keeping original aspects and my video knowledge is poor. I can remember I,P 
and B frames, DCTs etc from Uni, but nothing beyond mpeg1 basics...
ii) For playback I think I'll need to write a plugin that detects 
recompressed .vdr files and does on-the-fly transcode to mpeg1/2, so it can 
be fed back into the DVB card. Maybe my best bet is modifying the mplayer 
plugin so it fits in with the recording menu better? Trouble is mplayer 
doesn't seem very intelligent about keeping aspects and stuff - I can't even 
get it working with the plugin, never mind something like this! 

Has anyone looked into this kind of thing? Does something already exist that 
tackles this?

Thanks,

Mark