Authored w/Scenarist <> M2V + AC3 file size

[Eldorado]

I just encoded and reauthored a movie using CCE and Scenarist, all standard stuff I've done dozens of times before. But I'm a little confused this time around..

When encoding with CCE I plan the final file size of the video thru the Advanced button section, encode and video size comes out as expected. Add the size of the audio and I know what to expect.

But when I authored with Scenarist the total file size of the VOB's came out quite a bit bigger than the M2V + AC3 files were!

Here's my numbers:

M2V - 3,874,312,244
AC3 - 602,667,520

= 4,476,979,764

After Authoring - 4,598,433,792

I still have a 200 MB menu that I want included so the authored size will not fit. So my big question is, what happened, where did the extra 100+ mb come from? I've never had this problem before, always been spot on with my file sizes. I've tried it multiple times, and even once with IfoEdit and same results.. I always understood that the authored Size always = M2V + AC3 ?

[mpucoder]

What about the system level overhead? That's about 3% additional for any stream. Plus DVDs have the NAV pack beginning each VOBU, and filler packets at the end of each stream per VOBU. NAV packs are 2048 bytes every 0.5 seconds, or 4K per second. Filler amounts to an average of 1K per stream per VOBU, so for 2 streams that comes out to another 4K per second. For a 90 minute movie that's about 44MB. Add in approximately 134MB for system level headers mentioned above, and the total is about 178.5MB So an increase of about 222MB seems reasonable to me.

[Eldorado]

Ah ok thanks, I wasn't sure exactly what went on in the authoring process, I always thought of it as a straight mix of audio + video.

I'll have to start rethinking my final file sizes before authoring! :)

Are all these factors taken into consideration in apps such as DoItFast4U?

[Eyes`Only]

Are all these factors taken into consideration in apps such as DoItFast4U?
Of course it is! My app 'does it all fast for you' and calculates bitrates based on assets including mux overhead. It usually gets extremely close to 4.37 final project size.

[Nic]

@Eyes': Is there a post in this forum where you explain the numbers you used to create your calculator? It mentions Trilight's calculations but I can't find anything with Search...

If not ill just work it out from using your calc...

Cheers,
-Nic

[Eyes`Only]

Nic:

Trilight's work can be found at http://dvdguides.trilight.net

I'll PM you with calc info.