Compression Question

the_learninator wrote on 2/7/2005, 9:38 AM
I have about 2 hours of Digital Video (AVI) on my comp. I want to be able to fit as much of the 2 hours as possible on a DVD without reducing the quality of the video. I have Dr. Divx and my question is:

- will converting my current avi into dr. divx avi (making the avi's much smaller in file size).....will that matter when I render as mpeg 2 in vegas or will it be the same size for either avi?

Comments

Spot|DSE wrote on 2/7/2005, 9:42 AM
First, you might as well create the mpeg straight from the avi you've got, there is no value in converting to DivX at all if MPEG/DVD is your final target. It won't affect your file size at all in the end of things. Length and bitrate are what you need to worry about.
Fotis Vassis has a great MPEG calculator on the VASST site, you might wanna check that out.
www.vasst.com/login.htm, go to the Project/Veg files, his is one of the top downloads so it's on the front page.
riredale wrote on 2/7/2005, 10:22 AM
Do you plan to use a DVD disk as just a storage medium for viewing the data on a PC, or do you want to be able to view it also on a DVD player? If the former, then any of a number of compression formats can be used, but if you want to do the latter, then you need to make an "official" DVD, which uses MPEG2.

You can put 2 hours on an official DVD but you will need to use one of the better authoring programs to do so, and should also be compressing the audio using the popular AC-3 codec. You'll be using a bitrate of about 4.8Mb/sec, which is pretty low--you'll want to use a decent MPEG2 codec.

Divx offers higher performance than MPEG2 (better quality for a given bitrate) but, as mentioned, you can only view the disk on a PC with the Divx decoder installed; set-top DVD players won't play it. Another option would be Microsoft's WMV, which is easily as good as Divx and has the clout of Microsoft behind it. Some day soon I think most DVD players will also be able to handle WMV.
Spot|DSE wrote on 2/7/2005, 10:33 AM
Some day soon I think most DVD players will also be able to handle WMV.
Don't count on it. Microsoft announced this at NAB last year, but many others not only beat them to the punch, and Microsoft's newly renamed VC1 hasn't even been accepted as a standard yet. Surely would be nice, but at CES, Microsoft's big thing was using a DVD player that had a NIC in it, and then used networking to display the vid.
B_JM wrote on 2/7/2005, 10:59 AM
Microsoft has fumbled the ball on WMV completely ...
the_learninator wrote on 2/7/2005, 11:33 AM
ok i converted the a piece of the normal avi into divx dvd and it went from 50 to 10MB then I converted that 10MB piece into MPEG2 and it was 57megs (4 megs more than the normal avi conversion to MPEG2)

So I'll pretty much stick to the normal AVI for DVDs. I don't wally know the point of Divx then?
rs170a wrote on 2/7/2005, 11:46 AM
set-top DVD players won't play it.

The videohelp site lists 29 different models that will play DiVX. The problem is that only 2 are brand names that I recognize :-(

Mike