Convert DTS to AAC/AC3 automatically?

[oRBIT2002]

I've got some movies with DTS audio which I'd like to automatically convert to preferable AAC/AC3 with as little work as possible.
Anyone knows of an automated tool that can do something like this? Convert all audiostreams in file to an AAC or AC3 with equal amount of channels, if possible and recode that to a selected bitrate and then remove the old track and mux in the new track, without loss of other data, chapters/subtitles and so on.

[rollin_eng]

Ffmpeg should be able to do this.