Vamps was written to make cheap backups of DVDs under Linux. Back in 2003 Metakine published the source code of their M2Requantiser module. The idea was to make use of this great piece of software to create a transcoder for Linux for shrinking the content of a DVD9. This would enable backups on cheap single layer DVDRs (double layer burners weren't even available that time). The Metakine requantizer is pretty fast and so Vamps was designed not to break this outstanding performance.
Vamps builds a wrapper around the requantizer to extract the elementary MPEG2 video stream from the DVD's program stream, feed it through the requantizer and finally re-pack it into the program stream again. Besides this, Vamps allows to select audio and subtitle streams that should be copied into the output stream. This gives another small gain of disk space, since unwanted streams may be discarded.
Summed up, Vamps is only a very basic, but nevertheless essential tool to transcode DVD videos to a smaller size. Vamps does not need to write temporary data files, which is a major pro. Vamps is very fast. The downside is, that Vamps is not capable to make DVD backups on its own.
The latter was motivation enough to continue the work begun with vamps and to bring qVamps
into being. qVamps is a GUI, which enables the user to select titles from a DVD, uses Vamps for requantization and create a new DVD. qVamps uses dvdauthor for creation of the new DVD's data structures.