DVD maximum space question

[awesomelin]

I remmember reading that for a 700mb data cd you can fit 850mb of video on it, is it possible to fit more then 4.7gb on a 4.7gb dvd?

[jimmalenko]

https://www.videohelp.com/faq#740
https://www.videohelp.com/dvd.htm#1000

AFAIK you can't get much more than 4482MB (4.38GB) onto a SL DVD-R. I *think* there's a difference of about 7MB with SL DVD+Rs.

[waheed]

Max is 4.37GB

Theres a clever marketing scheme used here. In the computer world 1024 Kbytes is actually 1000 Kbytes(used by companies). so:

1000 = 1024
1000 x 1000 x 1000 = 1024 x 1024 x 1024
1GB = 1.0737 GB

Therefore

4.7GB/1.0737 = 4.377GB

Which means 4.7GB used by companies is actually 4.37GB in the computer world.

[pbhalerao]

Waheed's statement is correct. This is true of not only DVD media but also of Hard Disks. For example an HDD sold as 120GB in the shops actually results in a formatted capacity 114.44 GB. If you go back to the store and ask why a "tongue-in-cheek" service person may tell you that 'formating will take away some of the diskspace for use by the OS'.

[ROF]

Floppies and flash media too . . .

[Abond]

Interesting, only CD seems to be correct

[thevoelk]

Keep in mimd, CDs use a 14 bit code. It's called Extended Numerical Format. It has to do with the pits and lands, where you can't have two 1's or 0's next to each other (I can't remember which) since the bit is actually the transition from a land to a pit, not the pit/land itself.

[lordsmurf]

Interesting, only CD seems to be correct

Not really. A CD can hold more than it tells you using an alternate writing mode not commonly used.

[waheed]

Interesting, only CD seems to be correct

Not really. A CD can hold more than it tells you using an alternate writing mode not commonly used.

True. For example, a 700MB CD can hold 800MB of video in VCD format.