Real capacity of 650 mb and 700 mb cdr media?

[zener]

What is the real capacity of 650 mb and 700 mb cdr media? I mean if a 650 or 700 mb cdr can store a 650mb or700mb file or less than that? Thanks,

 

[Jeff7181]

I've read some divx guides and other video editing and encoding guides that it's possible to fit 800 MB onto a 700 MB CD if the burning program you use has the ability to leave out ALL the error correction code.

 

[Jeff7]

Keep the whole "megabyte" thing in mind too - I am pretty sure that CD's use the megabyte=1,000,000 bytes, not the...2^20 thing or whatever weird thing that is, which is what Windows uses to calculate Megabytes.

 

[1966]

Originally posted by: Jeff7181
I've read some divx guides and other video editing and encoding guides that it's possible to fit 800 MB onto a 700 MB CD if the burning program you use has the ability to leave out ALL the error correction code.

That only applies to a VCD or SVCD not divx .

800mpg burned as VCD can fit into a 700meg cdr.

But a 800meg Divx will never burn to a 700 meg cdr no matter what you do.

 

[Matthias99]

A standard 650MB CDROM will hold 74 minutes of uncompressed Redbook CD audio. That's essentially (other than a few headers at the beginning that use almost no space) WAV format audio at 44,100 samples per second, 16 bits per sample, in stereo.

2 (bytes/sample) * 44,100 (samples/sec) * 2 (stereo) = 176,400 B/sec.

176,400 (B/sec) * 74 (minutes/CD) * 60 (seconds/minute) = 783,216,000 B/CD.

783,216,000 / 1,024,768 (B/MB) = 764.286 MB/CD.

CD-R/RWs only hold 650MB because they have to leave extra space to account for manufacturing defects (commercial CDs don't have this problem because they're stamped). Higher-quality discs can set aside less space and so have more usable data area. That's why usually you can overburn 650MB CD-Rs to 700MB without a problem -- they're often the same discs they sell as 700MB, just the ones that didn't pass QC.

 

[manko]

Originally posted by: 1966
But a 800meg Divx will never burn to a 700 meg cdr no matter what you do.

Actually, you're wrong. Mode2 CD Maker Just don't store any mission critical data on a cd with this format.

With this tool you can create a CD/XA Mode2 Form2 ISO Bridge type CD, which is similar to VCD but open to any content (not just MPEG files). This way you can benefit from the greater storage space VCD offers (800 MB in a single 80 min. CD).

The problem is, Windows exposes such files in a special way, that needs the presence of either a special DirectShow filter (such as the XCD reader filter below), or direct application support in order to be able to use these files.