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== Optical Media Formats ==

You will normally encounter two types of readable optical media
and one type that is writable:

=== CD-DA ===

CD-DA contains audio tracks in a low level format that can only be
read by music CD players or by specialized software like
[[https://packages.debian.org/search?keywords=icedax|Debian packages:icedax]]
or {{{readom}}} from
[[https://packages.debian.org/search?keywords=wodim|Debian packages:wodim]].
Writing is done by burn programs in [[BurnCd#Audio_CD|audio mode]].

=== CD-ROM ===

CD-ROM contains data which are readble by normal means as from
normal data files or block devices. This format is only one of several
CD sector formats. DVD and BD media always appear as CD-ROM. Their video
or audio content is wrapped in read-only filesystems.
Writing is done by burn programs in
[[BurnCd#Burn_the_image_file_to_CD.2C_DVD.2C_or_BD|data mode]].

=== Read-Write Media ===

DVD+RW, DVD-RAM, and BD-RE media may also be written as normal
block devices. Formatted CD-RW and formatted DVD-RW may be used
that way by help of device files {{{/dev/pktcdvd*}}} and
program {{{pktsetup}}} out of
[[https://packages.debian.org/search?keywords=udftools:Debian packages:udftools]].
Their performance with random access writing is quite poor, though.
For larger amounts of data, you are better off with burn programs,
which are needed for CD-R, DVD-R, DVD+R, and BD-R, anyway.

Read-write media may be used like CD-ROM media as long as only
reading is desired.

Line 66: Line 104:
== CD ==
=== CDROM ===
<!> Beware! Much of this is '''old information'''. In the age of ''devfs'' and ''udev'' (or kernel version 2.6), you may not even have an (eg.) {{{/dev/hdc}}} if your drive isn't in the machine when you boot. As of Sarge, they're intended to be used as so:{{{
(1) infidel /home/keeling_ ls -al /media
total 4
drwxr-xr-x 4 root root 1024 2005-11-08 15:49 .
drwxr-xr-x 23 root root 1024 2005-11-03 19:24 ..
lrwxrwxrwx 1 root root 6 2005-11-03 18:12 cdrom -> cdrom0
drwxr-xr-x 2 root root 1024 2005-11-03 18:12 cdrom0
lrwxrwxrwx 1 root root 6 2005-11-08 15:49 cdrom1 -> cdrom0
lrwxrwxrwx 1 root root 7 2005-11-03 18:12 floppy -> floppy0
drwxr-xr-x 2 root root 1024 2005-11-03 18:12 floppy0
}}}
Furthermore, use of ''SCSI'' emulation drivers for ''ATAPI'' interfaces is ''deprecated''. Instead, you can (and should) use the correct device name directly:{{{
wodim speed=8 dev=/dev/hdc -eject -tao -data /scratch/iso/track_01.img
}}}
----

Translation(s): English - Français - Italiano


Devices

CDs, DVDs, and BDs are common types of removable media. Unlike other types of removable media (such as flash drives or external hard drives), they are normally used read-only and many of them require special burn programs. I.e. they are not mounted for writing like "normal" filesystems. CD, DVD, and BD are optical discs, so we can use that term to refer to them collectively.

Your PC will offer device files to access your optical disc(s). Such devices are typically called drives, players, or readers, and are generally detected as /dev/sr*, where * is a number starting at 0. (Thus your first drive will be /dev/sr0, second /dev/sr1, etc.) Symlinks such as /dev/cdrom, /dev/cdrw, /dev/dvd, or /dev/dvdrw (pointing to /dev/sr0) may also be created depending on your OS version and the detected capabilities of your device.

The sequence of device file numbers may change with each reboot. The directory /dev/disk/by-id contains symbolic links with names which show persistent name parts. Like:

/dev/disk/by-id/ata-HL-DT-ST_DVDRAM_GH24NSC0_K8AF33A3528
/dev/disk/by-id/usb-Optiarc_BD_RW_BD-5300S_306663601043-0:0

The name parts "HL-DT-ST_DVDRAM_GH24NSC0_K8AF33A3528" and "Optiarc_BD_RW_BD-5300S_306663601043" are supposed to persist even if you change the way the drives are attached to your computer.

Optical Media Formats

You will normally encounter two types of readable optical media and one type that is writable:

CD-DA

CD-DA contains audio tracks in a low level format that can only be read by music CD players or by specialized software like Debian packages:icedax or readom from Debian packages:wodim. Writing is done by burn programs in audio mode.

CD-ROM

CD-ROM contains data which are readble by normal means as from normal data files or block devices. This format is only one of several CD sector formats. DVD and BD media always appear as CD-ROM. Their video or audio content is wrapped in read-only filesystems. Writing is done by burn programs in data mode.

Read-Write Media

DVD+RW, DVD-RAM, and BD-RE media may also be written as normal block devices. Formatted CD-RW and formatted DVD-RW may be used that way by help of device files /dev/pktcdvd* and program pktsetup out of https://packages.debian.org/search?keywords=udftools:Debian packages:udftools. Their performance with random access writing is quite poor, though. For larger amounts of data, you are better off with burn programs, which are needed for CD-R, DVD-R, DVD+R, and BD-R, anyway.

Read-write media may be used like CD-ROM media as long as only reading is desired.

Video DVD

You can use many video players on Debian to read video DVDs, including VLC, Xine (or players with a Xine backend, such as totem-xine) or MPlayer. Since most DVDs are protected by CSS (Content Scramble System) you will require the installation of libdvdread4:

# apt-get install libdvdread4

libdvdcss2

libdvdcss is required for the decryption of CSS protected-DVDs. This cannot be obtained from the Debian repositories due to licence restrictions in various countries. Please also read the /usr/share/doc/libdvdread4/README.css file.

There are various sources for libdvdcss2:

  1. as deb directly from the project's homepage videolan: see http://download.videolan.org/debian/

  2. compiled from source from videolan http://download.videolan.org/pub/libdvdcss/

    • Read the file INSTALL and follow the instructions, e.g.
          ./configure --prefix=/usr
          make
          sudo make install
  3. from the unofficial repository deb-multimedia.org

setting the region

Some DVD players require the region to be set before they are able to play encrypted DVDs. This has to be done manually with regionset. The man-pages provide help in choosing the proper country-code.

Detecting and mounting

Use to detect your CD/DVD units:

wodim -scanbus

To check which special file /dev/cdrom is a symlink to (i.e. /dev/sr0, /dev/hdc or /dev/scd0), type:

ls -al /dev/cdrom*

Users need to be members of the "cdrom" group to use an optical device on Debian.

You can allow any user mount cdrom adding to fstab:

/dev/cdrom /mnt/auto/cdrom iso9660 noauto,users,ro 0 0

You can see if fstab points to the right device typing:

dmesg | grep ATAPI

Ripping

To almost quote Wikipedia, ripping is the process of copying input audio or video content (typically from an optical disc) and outputting to a "normal" storage filesystems. Ripping is typically more difficult than simple file copying (as when copying files from a flash drive or external hard drive) in that

  • the source content (i.e., the audio or video (or both) on the optical disc) typically is not formatted like data in a "normal" filesystem.

  • the source content is often encrypted (e.g., with CSS)

  • writing output audio and video files may require particular codecs.

  • the user may want to include metadata (aka tags, e.g., artist name, work title, release date) in the output. This metadata will typically require some format, e.g., ID3.

This involves at least 3 separate problems (discussed in more detail here):

  1. reading the optical disc (which this page is largely about)
  2. writing to the desired output format
  3. gathering or authoring metadata

FAQ

4GB per File limitation

Writing file larger than 4GB on an iso-9660 dvd is tricky (read wikipedia). The easiest way might be to use UDF.

  • Debian's mkisofs (genisoimage) might be limited to 4GB (read this).

Converting DVD

See also