[QUOTE=publicbob;2204790]Many thanks for your replies guys.
I was therefore wondering if I gave the software an mpeg-2 (dvd compliant of course) file if it would still go through the now unnecessary coverting process or if it would recognise that it is an mpeg-2 file and would just move straight on to the authoring and burning side of things. Though perhaps this depends on which software is used? Are there some that would and some that would not?
I had assumed before that I might be able to get around this if I did the converting to mpeg-2 myself and then authored it and mastered it myself, however despite being able to convert to mpeg-2 satisfactorily when it came to the conversion to vob format it would butcher the quality. Would it be possible to do the opposite of what you mentioned in that I might take a dvd compliant mpeg-2 file and rename the file extension and have it run as a vob file?
I guess I wasn’t clear on that. Yes it works both ways. As long as the mpeg 2 file is dvd compliant, you can change the file extension to .vob or .mpg and both work fine. My guess how a .vob is handled depends on the software but your situation is similar to mine a few years back and that is how I learned that you can change the file extension. With nero vision express, when you make a dvd, it takes any compatible file format (avi, h.264 or whatever) and converts it to .vob files so it is converting whatever file format to an mpeg 2 (and then does some simple authoring). The problem was that it too would convert (or perhaps it would be better to say it would re encode as it is going from mpeg 2 to mpeg 2) dvd compliant mpeg 2 files. Someone tipped me off that you could change the .mpg to .vob and it would prevent nero from re encoding it. For me it was a time issue, not a quality issue (I didn’t want to wait a couple hours for it to unnecessarily re encode and I was working with a lot of different videos).
So in short, with nero, it does re encode .mpg files when making a dvd, but if you change the file extension to .vob, it does NOT re encode. I have no idea if your software will do the same but its worth a try. If you have a dvd compliant .mpg file that you are happy with, just change the file extension to .vob, feed it to your program, and see what happens. It should be obvious if it works as encoding takes a long time. If it goes very quickly (minutes), then it probably didn’t re encode it (it just used your file as it was).
Did that make sense?