quality of editing vob file vs. "original" avi
 

Hi there,

I need to do a re-edit of some footage. All I have access to right now is a DVD (no copyright issues). I know that one option is to pull the VOB files in and edit in Vegas (inexpensive).

The other option on the table is to pay the company that originally created the DVD to render out an avi file (expensive) and edit from that.

My question is this - what will the quality difference be between a project using an edited VOB file from the DVD vs. an avi file rendered from the original project?

I want to be cost effective...but also want to be able to be upfront about the quality of the output that my customer can expect.

Thanks for any info any of you might be able to provide,
Dawn

Dubbing the original AVI should not be expensive and will give you much better quality, unless your intended editing is nothing more than plain cutting and pasting. If you need more extensive editing, you will lose quality.

I agree that it shouldn't be expensive to dub the original avi...but we received a quote that is significantly more expensive that it should be, IMHO.

That's really why I wanted to test out the VOB route, but you have confirmed my hunch, which was that editing from the original avi will allow for the best quality.

Thanks very much.

What exactly do you mean by "editing"? If you have to color correct, do transitions, composite in After Effects, than the only way is from the original AVI file. But if straight cuts will do, then you have other options with software that makes that kind of mpeg editing possible (regular NLE software was not designed to do mpeg editing).

Straight cuts...

OK... well, in this case I would use MPEG Streamclip to cut out the wanted portions and convert them to mpeg. Then I would use these mpeg files to author my new DVD - this way there will be no decompressing and re-compressing, there will be absolutely no loss in quality.

I have on many occasions, copied the Vobs to my Hard drive, imported them into vegas, render it as an AVI, edit and then render to mpg. My clients haven't had an issues with the quality.

I would test it on a 2 min section and see what you think.

Jon

Jon, since Vegas will let you pull in the vob files, is there a particular benefit to redering the vobs to avi before editing?

No benefit, only the disadvantage of a generation loss by converting to AVI and the second loss of re-compressing.

In general avoid conversion from one file type to another, unless you have no other solution.