Doing the Math

[montgal]

Hello Everyone:

The average movie is 700MB. Although, there are movies as large as 1.2 - 2 GB. A motion menu can be as large as 30MB, probably larger if you add particular features to the menus (e.g., video backgrounds, chapter video clips, submenus, etc).

Before burning, I get a message indicating the project is larger than the space allocated allows - Do you want to compressed?

If my blank diskette is, say, 4.7GB (DVD-R), I am wondering what process is happening to make projects larger than orginal output? Also, is there a disadvantage in having projects compressed as oppose to burning without compression?

Thx,
Montgal

[DVDDoug]

The average movie is 700MB.

Hmmmm... DVDs are MPEG-2, and the typical commercial DVD is a dual-layer DVD with maybe 6GB of audio/video. If you look at a DVD with Windows Explorer, you will find a handful of 1GB VOB files in the VIDEO_TS folder. (700MB would fit on a CD.)

You've got one of the "more advanced" formats, and you probably have less-than "DVD quality". When you make a regular video DVD, you need to convert to MPEG-2, which will result in a bigger file.

File size depends on bitrate:
File Size in MB = (Bitrate in kbps x Playing Time in minutes) / 140
(That's the combined audio & video bitrate).

All of the video compression schemes are lossy. Lower bitrate = smaller files = lower quality. However, some compression formats are more efficient than others and with a given bitrate/file size you can get better quality with MPEG-4 than with MPEG-2, etc. (A standards-compliant video DVD must be MPEG-1 or MPEG-2.)

[skier-hughes]

Hello Everyone:

The average movie is 700MB.

This sounds like there is more than one of them, some being large than 700mb and some smaller, so to have an average we make an assumption of say 3 movies of 700mb, that equals 2.1gb

Although, there are movies as large as 1.2 - 2 GB.
This also sounds like there are several movies, of a size of up to 2gb. if we take 3 movies of 1.2, 1.5 and 2gb, that gives us 4.7gb

A motion menu can be as large as 30MB, probably larger if you add particular features to the menus (e.g., video backgrounds, chapter video clips, submenus, etc).
Ok, assume you have only one menu and no submenu's as you don't mention any, so that's just 30mb

Before burning, I get a message indicating the project is larger than the space allocated allows - Do you want to compressed?

Not surprised, on my assumptions you have nearly 7gb trying to be put onto the disc. For a more accurate answer, maybe tell us exactly how many movies you are trying to put on the disc adn what size each one is. Of course, we also need to know what file type these movies are, a highly compressed file type will actually get alrger when converted to mpeg2, a file like dv.avi will get smaller and if they are already mpeg2 they'll stay the same.

If my blank diskette is, say, 4.7GB (DVD-R), I am wondering what process is happening to make projects larger than orginal output? Also, is there a disadvantage in having projects compressed as oppose to burning without compression?

Thx,
Montgal

[sjj1805]

Hour long "movies" of 700MB are one of the following:
DivX
Xvid
MPEG4

These are internet streaming formats widely used by TV Stations for their on line content. Whilst there are a few standalone DivX players - they are not what are traditionally termed "DVD Players" - for the stuff you buy at the supermarket or rent from the Video shop.

The traditional "DVD" comprises of VOB files which are in fact MPEG2 and have a standard play size of 4.3 Gigabytes per hour, though like the old fashioned VHS tapes you can get long play and extended long play etc so that you can get 2 or even 3 hours on a standard 4.3 GB blank DVD disc.