18.6. Creating and Using DVD Media

Contributed by Marc Fonvieille.
With inputs from Andy Polyakov.

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 the standard for video publishing.

Five physical recordable formats can be defined for a recordable DVD:

A single layer recordable DVD can hold up to 4,700,000,000 bytes which is actually 4.38 GB or 4485 MB as 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 such as DVD-R, DVD+R, or DVD-RW. Before choosing the type of media, ensure that both the burner and the DVD-Video player are compatible with the media under consideration.

18.6.1. Configuration

To perform DVD recording, use growisofs(1). This command is part of the sysutils/dvd+rw-tools utilities which support all DVD media types.

These tools use the SCSI subsystem to access the devices, therefore ATAPI/CAM support must be loaded or statically compiled into the kernel. This support is not needed if the burner uses the USB interface. Refer to Section 18.4, “USB Storage Devices” for more details on USB device configuration.

DMA access must also be enabled for ATAPI devices, by adding the following line to /boot/loader.conf:

hw.ata.atapi_dma="1"

Before attempting to use dvd+rw-tools, consult the Hardware Compatibility Notes.

Note:

For a graphical user interface, consider using sysutils/k3b which provides a user friendly interface to growisofs(1) and many other burning tools.

18.6.2. Burning Data DVDs

Since growisofs(1) is a front-end to mkisofs, it will invoke mkisofs(8) to create the file system layout and perform the write on the DVD. This means that an image of the data does not need to be created before the burning process.

To burn to a DVD+R or a DVD-R the data in /path/to/data, use the following command:

# growisofs -dvd-compat -Z /dev/cd0 -J -R /path/to/data

In this example, -J -R is passed to mkisofs(8) to create an ISO 9660 file system with Joliet and Rock Ridge extensions. Refer to mkisofs(8) for more details.

For the initial session recording, -Z is used for both single and multiple sessions. Replace /dev/cd0, with the name of the DVD device. Using -dvd-compat indicates that the disk will be closed and that the recording will be unappendable. This should also provide better media compatibility with DVD-ROM drives.

To burn a pre-mastered image, such as imagefile.iso, use:

# 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. To force the write speed, use -speed=. Refer to growisofs(1) for example usage.

Note:

In order to support working files larger than 4.38GB, an UDF/ISO-9660 hybrid file system must be created by passing -udf -iso-level 3 to mkisofs(8) and all related programs, such as growisofs(1). This is required only when creating an ISO image file or when writing files directly to a disk. Since a disk created this way must be mounted as an UDF file system with mount_udf(8), it will be usable only on an UDF aware operating system. Otherwise it will look as if it contains corrupted files.

To create this type of ISO file:

% mkisofs -R -J -udf -iso-level 3 -o imagefile.iso /path/to/data

To burn files directly to a disk:

# growisofs -dvd-compat -udf -iso-level 3 -Z /dev/cd0 -J -R /path/to/data

When an ISO image already contains large files, no additional options are required for growisofs(1) to burn that image on a disk.

Be sure to use an up-to-date version of sysutils/cdrtools, which contains mkisofs(8), as an older version may not contain large files support. If the latest version does not work, install sysutils/cdrtools-devel and read its mkisofs(8).

18.6.3. Burning a DVD-Video

A DVD-Video is a specific file layout based on the ISO 9660 and micro-UDF (M-UDF) specifications. Since DVD-Video presents a specific data structure hierarchy, a particular program such as multimedia/dvdauthor is needed to author the DVD.

If an image of the DVD-Video file system already exists, it can be burned in the same way as any other image. If dvdauthor was used to make the DVD and the result is in /path/to/video, the following command should be used to burn the DVD-Video:

# growisofs -Z /dev/cd0 -dvd-video /path/to/video

-dvd-video is passed to mkisofs(8) to instruct it to create a DVD-Video file system layout. This option implies the -dvd-compat growisofs(1) option.

18.6.4. Using a DVD+RW

Unlike CD-RW, a virgin DVD+RW needs to be formatted before first use. It is recommended to let growisofs(1) take care of this automatically whenever appropriate. However, it is possible to use dvd+rw-format to format the DVD+RW:

# dvd+rw-format /dev/cd0

Only perform this operation once and keep in mind that only virgin DVD+RW medias need to be formatted. Once formatted, the DVD+RW can be burned as usual.

To burn a totally new file system and not just append some data onto a DVD+RW, the media does not need to be blanked first. Instead, write over the previous recording like this:

# growisofs -Z /dev/cd0 -J -R /path/to/newdata

The DVD+RW format supports appending data to a previous recording. This operation consists of merging a new session to the existing one as it is not considered to be multi-session writing. growisofs(1) will grow the ISO 9660 file system present on the media.

For example, to append data to a DVD+RW, use the following:

# growisofs -M /dev/cd0 -J -R /path/to/nextdata

The same mkisofs(8) options used to burn the initial session should be used during next writes.

Note:

Use -dvd-compat for better media compatibility with DVD-ROM drives. When using DVD+RW, this option will not prevent the addition of data.

To blank the media, use:

# growisofs -Z /dev/cd0=/dev/zero

18.6.5. Using a DVD-RW

A DVD-RW accepts two disc formats: incremental sequential and restricted overwrite. By default, DVD-RW discs are in sequential format.

A virgin DVD-RW can be directly written without being formatted. However, a non-virgin DVD-RW in sequential format needs to be blanked before writing a new initial session.

To blank a DVD-RW in sequential mode:

# dvd+rw-format -blank=full /dev/cd0

Note:

A full blanking using -blank=full will take about one hour on a 1x media. A fast blanking can be performed using -blank, 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

Since growisofs(1) automatically attempts to detect fast blanked media and engage DAO write, -use-the-force-luke=dao should not be required.

One should instead use restricted overwrite mode with any DVD-RW as this format is more flexible than the default of incremental sequential.

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

To append some data to a previous recording, use -M with growisofs(1). However, if data is appended 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. Instead, overwrite the disc with -Z. It is also possible to grow an existing ISO 9660 file system written on the disc with -M. The result will be a one-session DVD.

To put a DVD-RW in restricted overwrite format, the following command must be used:

# dvd+rw-format /dev/cd0

To change back to sequential format, use:

# dvd+rw-format -blank=full /dev/cd0

18.6.6. Multi-Session

Few DVD-ROM drives support multi-session DVDs and most of the time 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 with a DVD+RW or a DVD-RW in restricted overwrite mode will append data while merging the new session to the existing one. The result will be a single-session disc. Use this method to add data after an initial write on these types of media.

Note:

Since some space on the media is used between each session to mark the end and start of sessions, one should add sessions with a 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.

18.6.7. For More Information

To obtain more information about a DVD, use dvd+rw-mediainfo /dev/cd0 while the disc in the specified drive.

More information about dvd+rw-tools can be found in growisofs(1), on the dvd+rw-tools web site, and in the cdwrite mailing list archives.

Note:

When creating a problem report related to the use of dvd+rw-tools, always include the output of dvd+rw-mediainfo.

18.6.8. Using a DVD-RAM

DVD-RAM writers can use either a SCSI or ATAPI interface. For ATAPI devices, DMA access has to be enabled by adding the following line to /boot/loader.conf:

hw.ata.atapi_dma="1"

A DVD-RAM can be seen as a removable hard drive. Like any other hard drive, the DVD-RAM must be formatted before it can be used. In this example, the whole disk space will be formatted with a standard UFS2 file system:

# dd if=/dev/zero of=/dev/acd0 bs=2k count=1
# bsdlabel -Bw acd0
# newfs /dev/acd0

The DVD device, acd0, must be changed according to the configuration.

Once the DVD-RAM has been formatted, it can be mounted as a normal hard drive:

# mount /dev/acd0 /mnt

Once mounted, the DVD-RAM will be both readable and writeable.

All FreeBSD documents are available for download at http://ftp.FreeBSD.org/pub/FreeBSD/doc/

Questions that are not answered by the documentation may be sent to <[email protected]>.
Send questions about this document to <[email protected]>.