I hope no one really finds this useful. But, for those who end up in same situation I nominally do. And, that place is one where there are CDs and DVDs that are unlabelled.
So there are sets of Discs and you are not sure which ones have data and which ones are empty. And, there are some that are usable.
Here is one way of determining which basket to place each Disc.
CDCheck is free and very accessible.
Download CDCheck from http://www.kvipu.com/CDCheck/download.php.
The version is 220.127.116.11 and the cdcheck.exe is dated October 9th, 2008.
One can choose the setup binary or the zipped file.
The setup route goes through the usual install process. And, the zipped file simply extracts the binary and one can run the exe, as is.
Results of CD Evaluation
Double Layer ( DL ) – Capacity 7.96 GB
Double Layer ( DL ) – Capacity 4.37 GB
CD – Used
Capacity 1.63 GB
- We got back a capacity of 1.6 GB
- As we did not get back a standard capacity such as 4.7 or 7.96 gb, we can be informed that the disc contains some data and is not blank
- We got back more than the standard; the standard being:
- Disc type
- Unrestricted Use Disc
- Manufacturer ID
- Dye type
- Media Type
- Media Revision
- In addition to the Standard, we might receive mutation of the following:
- Indicative Target Writing type
- Start Time of Lead-In
- Last Possible Start Time of Lead-Out
My Blank DVD-R is only 4.37GB’s?
It’s a mathematics thing. DVDs are 4.7GB. However, that’s measured using “1GB = 1,000,000,000 bytes.” Which is the correct way to measure a gigabyte (according to the IEEE and other standards organizations). However, Windows shows the measurement in GiB (or Gibibytes). This is the “old” measurement for gigabytes that’s still in use by Microsoft. In this measurement, 1GB = 1,073,741,824 bytes. Therefore, the DVD is 4.7GB = 4,700,000,000 bytes = 4.37GiB.
Basically, you’re just seeing a mislabeling on Microsoft’s part. They should show it as 4.37GiB. That would be less confusing. The disk is, in fact, 4.7 gigabytes (as advertised). But Microsoft has never been known for following industry standards. 😉
True Capacity of 8.5Gig DVD
“I want to ensure they will play on many different types of optical drives“………. 8.5gb DVDs are double layer, so they will only work on DL drives. If you try to use them on standard single layer drives, they won’t work at all.
The maximum storage on an 8.5gb DVD is 7.96gb. The advertisers/manufacturers use decimal, so they say gigabyte/gb means 1000 to make the customer think they’re getting more for their money, but computers are binary so they use 1024. That’s why there’s a difference of about 500mb between the advertised capacity and the actual capacity. Single layer 4.7gb DVDs can hold about 4.3gb.
I wish that empty discs are explicitly labelled. But, taken that they are not, it is not too difficult to infer whether a Disc is empty or not.
One should simply correlate the Capacity with standard disc sizes; CD is 4.37 GB and DVD is 7.96 GB.