#CD ID Number – Help!!!
7 messages in this thread
A number of CD-ROM programs written for Windows can identify an audio CD by
a unique number derived from the CD itself. MusicBox from Microsoft is a
prime example. Can anyone tell me how to access this number via Windows
(or when in Windows)?
Any and all help is appreciated.
Please send comments via compuserve mail if possible.
Thanx in advance.
Pete S.
I've never heard of such a thing about a UNIQUE number. I guess you can
check sector 16 and see if it has a primary volume descriptor if it does
than it is a CD-ROM.
You might try the Microsoft developer forums. And you might also try the
COREL forum too. (GO MICROSOFT) and (GO COREL)
Peter,
I don't know specifically about a unique number but virtually any CD with
more than one track has audio. Come to think of it there must be
indentifying info of some sort since, when using one of the CD player audio
packages I have (I think it's the Corel) it labels each track as to whether
it is data or audio.
Sandy
The Q-code has a provision for mode 1, mode2 and mode 3 q-codes. The CD
can have a number and each track can have a number. Most discs don't have
either code, and when mode 2 is present, it is most often zero'ed out. So,
a number is obtained for program use by looking at the TOC which has a
start track #, ending track number, lead-out time and the start time of
each track in min, sec and frame, and the type of info in each track, data
or audio. This is different enough to make it unlikely for two cds to have
the same info unless they are rom data with one track. Sometimes the data
for two different pressings of the same disc is different, but it is not
like for the same user to have two discs of the same title. (like->likely).
This works weill enough.
This is a little out of my depth, but I'm going to go out on a limb and
suggest that the ID you are looking for is contained in the system-readable
VTOC of the CD, which identifies the content of the disc.
I'll look into it further… the question has piqued my curiosity as well.
I missed part of the thread but if you are trying to identify a cd that's
ISO-9660 or HighSierra in DOS, there are several ways.
1. _dos_findfirst in C. searching for attribute 8, _A_VOLID. This gets
you the volume label. There is a corrsponding low level DOS call.
2. MSCDEX function 5, via int 2F, read VTOC. This gets you the vol
table of contents which has label info. Note that its in a different place
for ISO-9660 and High Sierra.
3. LOW Level CD-ROM call to GET_UPC. This will get the UPC code from
the disc if the manufacturer had one written and the drive can read it.
Peter –
I asked the programmer who developed our CD-ROM driver if there is a
unique field in the CD-ROM file system (ISO 9660 or High Sierra) which
identifies the CD as having audio tracks. He said that the file system
itself does not contain the data but that you can send a command to the
drive which will respond with the number of audio tracks available. Hope
that this helps. -> Eric