Translating movie subtitles is my new hobby. I had no previous knowledge of what subtitles are, how they are embedded in a DVD movie, how to rip them off, how to create new subtitles, and then finally how to prepare a DVD with translated subtitles that could be played on most popular software, hardware and standalone DVD players. I found out that it was not an easy job to embed UTF-8 encoded text on DVD as a separate subtitle stream. So I decided to hardsub my movie, which means that users will not have the option to turn off the Urdu subtitles.
First I needed to rip the DVD to my hard disk and there are some very good tools available for Ubuntu Linux that work great. (Warning: As always, check the relevant copyright laws for your country regarding the backup of DVDs). I used dvd::rip which rips and transcodes the files into avi format. It also provides the option to rip the subtitles separately, but since most DVD movies has subtitles embedded in streams with Pictures it was basically useless for me. However there are other tools that rip the subtitles and also help you save them as text using OCR.