Yeah, this is problem, no informations, just sources (btw: all I saw are bad written). But how these guys wrote their code if zero descriptions?
Jürgen Schlottke has one of the (the ?) best Barcode components for Delphi. If you buy his software, you'd get all the information you want. Again, as code, not on the silver platter.
As Union wrote, you have to purchase the definition (i.e. 'silver platter') from the ISO.