Hardware Reference
In-Depth Information
hard drive (staged) before being written to the CD in one session. Additional sessions can be
written to the same disc, but a 50MB overhead exists for each session. This gives some of
the appearance of packet writing, but it is not really the same thing. To read packet-written
discs in the UDF 1.5 or later format, you must install a UDF reader just as with previous
versionsofWindows.InsteadofusingIMAPI,Irecommendinstallingathird-partyCD-mas-
tering program that also includes packet-writing UDF support, such as Roxio Creator 2011
or Nero.
When you remove a packet-written disc from the drive, the packet-writing software first
asks whether you want the files to be visible in all drives. If you do, you must close the
session. Even if the session is closed, you can still write more to the disc later, but there is
an overhead of wasted space every time you close a session. If you are going to read the
disc in a rewritable drive, you don't have to close the session because it will be capable of
reading the files even if the session isn't closed.
Caution
Ifyouarenotsurewhattypeofdrivewillbeusedtoreadthemedia,Irecommendclosingthe
media.Thisenablesusersofvarioustypesofdrivestoreadthemedia,althoughacompatible
UDF reader program must be installed in some cases.
A newer standard called Mount Rainier (Mt. Rainier) adds even more capability to packet
writing. With Mount Rainier, packet writing can become an official part of the operat-
ing system (OS) and the drives can support the defect management necessary to make
them usable as removable storage in the real world. For more information, see the section
“
Mount Rainier
” later in this chapter.
Note
As part of Service Pack 1, Microsoft released updates for Windows XP that add native
support for the Mount Rainier standard, which supports full drag-and-drop packet writing
through CD-MRW drives as well as DVD+MRW drives. Microsoft Windows 7 and Vista in-
clude native support of Mount Rainier.
Photo CD
First announced back in 1990 but not available until 1992, Photo CD was a standard that
used CD-R discs and drives to store photos. Although Kodak originally sold Photo CD
“players” that were connected to TVs, most Photo CD users used computer-based optical
drives along with software to decode and display the photos.
Perhaps the main benefit Photo CD brought to the table is that it was the first CD format
to use the Orange Book Part II (CD-R) specification with multisession recordings. Addi-
