StreamDVD is a fast tool to backup Video DVDs 'on the fly', there will
be no ripping, demultiplexing, recoding, remultiplexing...

You can select the wanted title, chapters, video, audio and subpicture
streams, a resize factor, and StreamDVD will write a 'ready to author'
vob file to stdout.

WWW: http://www.badabum.de/streamdvd.html