19.7 Creating and Using DVD Media

19.7.1 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 the standard for video publishing.

Five physical recordable formats can be defined for 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 rewritable version of the DVD-R standard. A DVD-RW can be rewritten about 1000 times.

• DVD-RAM: This is a rewritable format which can be seen as a removable hard drive. However, this media is not compatible with most DVD-ROM drives and DVD-Video players as only a few DVD writers support the DVD-RAM format. Refer to for more information on DVD-RAM use.

• DVD+RW: This is a rewritable 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 as 1 kilobyte is 1024 bytes.

19.7.2 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 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.

19.7.3 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.

19.7.4 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.

19.7.5 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.

To blank the media, use:

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

19.7.6 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

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

19.7.7 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.

19.7.8 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.

19.7.9 Using a DVD-RAM

hw.ata.atapi_dma="1"

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

# mount /dev/acd0 /mnt