Why can 4.7GB DVD+R burn max only 4.36GB of data?

A

andybiz_2005

Well-known member
Dear all,

I've been backing up all my past source video files (uncompressed .avi) to normal 4.7GB DVD+R discs for a long time. (video data)

The physical DVD+R says maximum capacity is 4.7GB, but I would like to know why I can only burn up to a maximum size of only 4.36GB with my burning software (Nero 7). What happened to the remaining digits on the disc?

I've searched this on google, but didn't find a satisfactory answer explaining why DVD+R discs can burn 4.36GB when they say 4.7GB on the physical disc.

Thanks in advanced.

Andrew
 
I think they have to have some firmware (probably not the right word) so that the DVD player can read them.

Ex: A 30gb ipod holds about 27gb of music.
 
it has to do with the differences in the definition of a "gigabyte".

a gigabyte can be either 1,000,000,000 bytes or 1,073,741,824, depending on who's counting it.

http://en.wikipedia.org/wiki/Gigabyte


basically the storage capacity is measured using 1,000,000,000, while the file size is measured using the larger number. Since the "gigabyte" for measuring files and software is larger, fewer gigs can fit than what it is rated for.

Basically it's a computer version of an accounting error, at least that's how I understand it.
 
Not an accounting error, just a double standard. Or marketing hype. The numbers in powers of 2 are accurate; while the numbers in powers of 10 seem better and are (arguably" easier for people to grasp. But of course having a double standard is just annoying, especially when there's no clear standard for distinguishing binary and decimal measures!
 
There is also an option in some burning progs called "DVD+R compatibility" which burns after 30mm from start of disc. This will reduce your data capacity of the disk
 
ullanta is right, there is a difference in how the numbers are reported. Marketing always finds the best way to represent something to entice buyers.

But in addition to that, there is another explanation. Disk capacity rating is the total available storage provided on the medium in question (CD, DVD, Hard Drive, etc). However, in order for the computer to store and then effectively retrieve there needs to be additional information stored to the medium to identify what was stored and where it was stored, a table of contents. This takes some of the space.

Those two factors combined explain why there is a disparity between the available storage space noted and what is actually usable.
 
You must log in or register to reply here.
Back
Top