Where is ID for DVD disks saved?

Stupid question, probably, but my son hasn't a clue.

My DVD video "player" is my computer's DVD-RAM drive (plus Power DVD). Lately it quite often has trouble recognizing there's even a disk in the drive, let alone being able to identify and play the DVD.

Usually ejecting the disk and rotating it a little then trying again will do the trick (the most obvious indication being the disk's volume-name appearing if I open My Computer and look at the drive's icon), or failing that, a reboot will often help. As a last resort, I'll run my lens-cleaner disk which never fails (it's a CD, not DVD) to run but doesn't always get the DVD to be properly readable.

My question is, where physically on the "working" side of a DVD is the volume-ID and related data stored, so I know where to pay special attention when I'm checking that the disk itself is in good shape and (probably) isn't the problem? Many thanks.

Oh, and I've got autoplay disabled for the drive, if that's relevant.

 

I'm not sure that info is always written in the same place. see
http://electronics.howstuffworks.com/dvd2.htm

I would re-enable the autoplay (the detection might work better)

 

Thanks, Cudni, that article was fascinating and informative. Couldn't find anything relating to my question, though, other than inferentially in the discussion of two-layer disks in which the 2nd layer starts at the outside to speed up the "crossover". It seems likely, though, that I should be paying particular attention to the cleanliness of the innermost portion of the disks, since the disk ID is probably physically close to the beginning of the video data.

I'll give auto-play a try too, thanks for that ... most security experts seem to agree it should be disabled, but since in my case we're talking strictly about commercial videos (usually from Amazon) that's probably not a matter for concern.

Thanks again, and best,
Mike