26 Oct
2006
26 Oct
'06
4:33 p.m.
Jan-Benedict Glaw wrote:
For a pure data CD, an ISO image is probably good
enough. (Though you
may want to additionally get hold of all the TOC/ATIP information
that's not inside the ISO image.)
OpenVMS CDs and Ultrix CDs are not ISO9660 just for starters so I
think you really do need a dump of the entire CD (via dd or any
of the CD/DVD-writing programs out there). Even if it looks like
an ISO9660 CD that's not enough. I've written CDs that have both
an ODS-2 filesystem and an ISO9660 filesystem (in my case the data
was shared between the two but there could easily have been data
that existed in only one or the other).
For anything else (CD+G, CDI, ...) you need to
understand how a CD
works and at which layer this type of CD is operating.
Especially for "copy-protected" CDs, which may contain premastered
broken sectors, you probably also want to get hold of the C2 level
error bits.
Ideally you would want a dump of the raw CD "bitstream" (I think it
has a proper name but I don't know it) but for most CDs that's far more
than is needed. If the CD device for the target system never made that
much info available you probably don't need it. Even having all that
info won't necessarily be enough to recreate a CD (the PS copy
protection
scheme you mention relies on deliberate error data and I think even
modern
writers don't give you enough control to reproduce such a disc).
Antonio