Зипись DVD
Creating and Using Optical Media (DVDs)
Contributed by Marc
Fonvieille. With inputs from Andy Polyakov.
1
Introduction
Compared to the CD, the DVD is the next
generation of optical media storage technology. The DVD can hold more
data than any CD and is nowadays the standard for video
publishing.
Five physical recordable formats can be defined
for what we will call a recordable DVD:
DVD-R: This was the
first DVD recordable format available. The DVD-R standard is defined
by the DVD Forum. This format is write once.
DVD-RW: This is
the rewriteable version of the DVD-R standard. A DVD-RW can be
rewritten about 1000 times.
DVD-RAM: This is also a
rewriteable format supported by the DVD Forum. A DVD-RAM can be seen
as a removable hard drive. However, this media is not compatible with
most DVD-ROM drives and DVD-Video players; only a few DVD writers
support the DVD-RAM format.
DVD+RW: This is a rewriteable
format defined by the DVD+RW Alliance. A DVD+RW can be rewritten
about 1000 times.
DVD+R: This format is the write once
variation of the DVD+RW format.
A single layer recordable DVD
can hold up to 4,700,000,000 bytes which is actually 4.38 GB or 4485
MB (1 kilobyte is 1024 bytes).
Note: A distinction must be
made between the physical media and the application. For example, a
DVD-Video is a specific file layout that can be written on any
recordable DVD physical media: DVD-R, DVD+R, DVD-RW etc. Before
choosing the type of media, you must be sure that both the burner and
the DVD-Video player (a standalone player or a DVD-ROM drive on a
computer) are compatible with the media under consideration.
2
Configuration
The program growisofs(1) will be used to perform
DVD recording. This command is part of the dvd+rw-tools utilities
(sysutils/dvd+rw-tools). The dvd+rw-tools support all DVD media
types.
These tools use the SCSI subsystem to access to the
devices, therefore the ATAPI/CAM support must be added to your
kernel. If your burner uses the USB interface this addition is
useless, and you should read the Section 16.5 for more details on USB
devices configuration.
You also have to enable DMA access for
ATAPI devices, this can be done in adding the following line to the
/boot/loader.conf file:
hw.ata.atapi_dma="1"
Before
attempting to use the dvd+rw-tools you should consult the
dvd+rw-tools' hardware compatibility notes for any information
related to your DVD burner.
Note: If you want a graphical user
interface, you should have a look to K3b (sysutils/k3b) which
provides a user friendly interface to growisofs(1) and many others
burning tools.
3 Burning Data DVDs
The growisofs(1) command
is a frontend to mkisofs, it will invoke mkisofs(8) to create the
file system layout and will perform the write on the DVD. This means
you do not need to create an image of the data before the burning
process.
To burn onto a DVD+R or a DVD-R the data from the
/path/to/data directory, use the following command:
# growisofs
-dvd-compat -Z /dev/cd0 -J -R /path/to/data
The options -J -R
are passed to mkisofs(8) for the file system creation (in this case:
an ISO 9660 file system with Joliet and Rock Ridge extensions),
consult the mkisofs(8) manual page for more details.
The
option -Z is used for the initial session recording in any case:
multiple sessions or not. The DVD device, /dev/cd0, must be changed
according to your configuration. The -dvd-compat parameter will close
the disk, the recording will be unappendable. In return this should
provide better media compatibility with DVD-ROM drives.
It is
also possible to burn a pre-mastered image, for example to burn the
image imagefile.iso, we will run:
# growisofs -dvd-compat -Z
/dev/cd0=imagefile.iso
The write speed should be detected and
automatically set according to the media and the drive being used. If
you want to force the write speed, use the -speed= parameter. For
more information, read the growisofs(1) manual page.
4 Burning a
DVD-Video
A DVD-Video is a specific file layout based on ISO
9660 and the micro-UDF (M-UDF) specifications. The DVD-Video also
presents a specific data structure hierarchy, it is the reason why
you need a particular program such as multimedia/dvdauthor to author
the DVD.
If you already have an image of the DVD-Video file
system, just burn it in the same way as for any image, see the
previous section for an example. If you have made the DVD authoring
and the result is in, for example, the directory /path/to/video, the
following command should be used to burn the DVD-Video:
#
growisofs -Z /dev/cd0 -dvd-video /path/to/video
The -dvd-video
option will be passed down to mkisofs(8) and will instruct it to
create a DVD-Video file system layout. Beside this, the -dvd-video
option implies -dvd-compat growisofs(1) option.
5 Using a
DVD+RW
Unlike CD-RW, a virgin DVD+RW needs to be formatted
before first use. The growisofs(1) program will take care of it
automatically whenever appropriate, which is the recommended way.
However you can use the dvd+rw-format command to format the DVD+RW:
#
dvd+rw-format /dev/cd0
You need to perform this operation just
once, keep in mind that only virgin DVD+RW medias need to be
formatted. Then you can burn the DVD+RW in the way seen in previous
sections.
If you want to burn new data (burn a totally new
file system not append some data) onto a DVD+RW, you do not need to
blank it, you just have to write over the previous recording (in
performing a new initial session), like this:
# growisofs -Z
/dev/cd0 -J -R /path/to/newdata
DVD+RW format offers the
possibility to easily append data to a previous recording. The
operation consists in merging a new session to the existing one, it
is not multisession writing, growisofs(1) will grow the ISO 9660 file
system present on the media.
For example, if we want to append
data to our previous DVD+RW, we have to use the following:
#
growisofs -M /dev/cd0 -J -R /path/to/nextdata
The same
mkisofs(8) options we used to burn the initial session should be used
during next writes.
Note: You may want to use the -dvd-compat
option if you want better media compatibility with DVD-ROM drives. In
the DVD+RW case, this will not prevent you from adding data.
If
for any reason you really want to blank the media, do the
following:
# growisofs -Z /dev/cd0=/dev/zero
6 Using a
DVD-RW
A DVD-RW accepts two disc formats: the incremental
sequential one and the restricted overwrite. By default DVD-RW discs
are in sequential format.
A virgin DVD-RW can be directly
written without the need of a formatting operation, however a
non-virgin DVD-RW in sequential format needs to be blanked before to
be able to write a new initial session.
To blank a DVD-RW in
sequential mode, run:
# dvd+rw-format -blank=full /dev/cd0
Note:
A full blanking (-blank=full) will take about one hour on a 1x media.
A fast blanking can be performed using the -blank option if the
DVD-RW will be recorded in Disk-At-Once (DAO) mode. To burn the
DVD-RW in DAO mode, use the command:
# growisofs
-use-the-force-luke=dao -Z /dev/cd0=imagefile.iso
The
-use-the-force-luke=dao option should not be required since
growisofs(1) attempts to detect minimally (fast blanked) media and
engage DAO write.
In fact one should use restricted overwrite
mode with any DVD-RW, this format is more flexible than the default
incremental sequential one.
To write data on a sequential
DVD-RW, use the same instructions as for the other DVD formats:
#
growisofs -Z /dev/cd0 -J -R /path/to/data
If you want to
append some data to your previous recording, you will have to use the
growisofs(1) -M option. However, if you perform data addition on a
DVD-RW in incremental sequential mode, a new session will be created
on the disc and the result will be a multi-session disc.
A
DVD-RW in restricted overwrite format does not need to be blanked
before a new initial session, you just have to overwrite the disc
with the -Z option, this is similar to the DVD+RW case. It is also
possible to grow an existing ISO 9660 file system written on the disc
in a same way as for a DVD+RW with the -M option. The result will be
a one-session DVD.
To put a DVD-RW in the restricted overwrite
format, the following command must be used:
# dvd+rw-format
/dev/cd0
To change back to the sequential format use:
#
dvd+rw-format -blank=full /dev/cd0
7 Multisession
Very few
DVD-ROM drives support multisession DVDs, they will most of time,
hopefully, only read the first session. DVD+R, DVD-R and DVD-RW in
sequential format can accept multiple sessions, the notion of
multiple sessions does not exist for the DVD+RW and the DVD-RW
restricted overwrite formats.
Using the following command
after an initial (non-closed) session on a DVD+R, DVD-R, or DVD-RW in
sequential format, will add a new session to the disc:
# growisofs
-M /dev/cd0 -J -R /path/to/nextdata
Using this command line
with a DVD+RW or a DVD-RW in restricted overwrite mode, will append
data in merging the new session to the existing one. The result will
be a single-session disc. This is the way used to add data after an
initial write on these medias.
Note: Some space on the media
is used between each session for end and start of sessions.
Therefore, one should add sessions with large amount of data to
optimize media space. The number of sessions is limited to 154 for a
DVD+R, about 2000 for a DVD-R, and 127 for a DVD+R Double Layer.
8
For More Information
To obtain more information about a DVD,
the dvd+rw-mediainfo /dev/cd0 command can be ran with the disc in the
drive.
More information about the dvd+rw-tools can be found in
the growisofs(1) manual page, on the dvd+rw-tools web site and in the
cdwrite mailing list archives.
Note: The dvd+rw-mediainfo
output of the resulting recording or the media with issues is
mandatory for any problem report. Without this output, it will be
quite impossible to help you.