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View Full Version : 4.29GB Becomes 4.58GB When Authored in Scenarist Pro


BassPig
20th November 2003, 12:15
This one really has me over a barrel:

The sum total of all assets for a particular DVD project is 4.29GB.

When authored in Scenarist Pro, this expanded to 4.58GB mysteriously and resulted in a failure due to inadequate space on the target DVD media. (DVD-R)

The first time I became aware of this inflation of project size was when I chose to reauthor a project I had originally done in DVD-it. The project had a similar size for the assets, actually, a little larger, about 4.31GB total--which successfully authored in DVD-it. I took those same assets and reauthored them in Scenarist Pro and the project image size became too big to fit.

So now here I am blowing a deadline because I have to go back and reencode the whole darned project, re import the MPEG, re add the chapters, marry it to the ac3 track and then put it all back together in the Scenario editor. Easily another whole day. Problem is, release day is Nov 22nd, and I have to FedEx the "gold" master to the venue owners where the video was shot, for clearance today.

The problem is that I don't know how much smaller I need to make the MPEG bitrate. I used a bitrate calculator to arrive at my settings. I hit my target filesize and am actually a little smaller than my 4.31GB target for the assets combined. But Scenerist refuses to burn the master disc because it reports an image size of 4.58GB.
Where is this extra size coming from? That's some 270MB of extra unknown data that somehow developed. Any ideas?

coona
20th November 2003, 15:24
It is prety easy :). You need some space for muxing data (video/audio/subtitles) together. Simle equation is:

(your video stream + your audio streams) = total size of your media * 0,97

so

4483*0,97=total size of your video and audio streams for DVD+R
4487*0,97=total size of your video and audio streams for DVD-R.

If you have some other data (like menus for example) you have take off some space for them so equation is:

(4483 - extras - menu)*0,97 = your video stream + your audio streams.

Each subtitle stream takes about 2 or 3 MBs.

Hope this help :).

EDITED:

This (http://forum.doom9.org/showthread.php?s=&threadid=55032) post is more comprehensible, he he.

BassPig
21st November 2003, 02:07
Thanks for the reply.
Apparently this must be specific to Scenarist, as I found that I could not reauthor a DVD-it project and get it to fit in Scenarist without having to reencode the assets at a lower bitrate than that used for DVD-it. But I did read that Scenarist uses a different mux engine, so this could be the reason.
At least I now have some rules of thumb to apply, using the formulae indicated. Thanks.

coona
21st November 2003, 13:14
I was looking hours for this (http://forum.doom9.org/showthread.php?s=&threadid=55197) thread :cool:. I guess that each authoring sw has to use similar procedures...

Eyes`Only
5th December 2003, 16:51
This isn't a Scenarist issue, it's a basic fact of .vob content. Any muxer that could mux together audio/video and subs and not give you overhead is a muxer I wouldn't use. That'd be waaay outta spec!