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hpr3986 :: Optical media is not dead

Archer72 shows command line options for creating and writing iso files

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Hosted by Archer72 on 2023-11-13 is flagged as Clean and is released under a CC-BY-SA license.
Command line, Create ISO, Burn ISO, Optical media, DVD, CD, Blu-ray. 1.
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Duration: 00:07:15


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Media size

4.7Gb DVD - Actual capacity: 4.377Gb

What is the actual storage capacity of a dvd disc

A disc with a 25GB capacity is the equivalent of 23.28 gigabytes Normally rated at 50GB, in practice they can record about 46.57GB of data

What is the maximum capacity of a blu ray disc

Generate ISO image from directory

genisoimage -U -R -allow-lowercase -allow-multidot -o mydvd.iso "$1"

Alternative is mkisofs


Allows "untranslated" filenames, completely violating the ISO9660 standards described above. Enables the following flags: -d -l -N -allow-leading-dots -relaxed-filenames -allow-lowercase -allow-multidot -no-iso-translate. Allows more than one `.' character in the filename, as well as mixed-case filenames. This is useful on HP-UX, where the built-in cdfs filesystem does not recognize any extensions. Use with extreme caution.


Generate SUSP and RR records using the Rock Ridge protocol to further describe the files on the ISO9660 filesystem.

[Wikipedia - ISO 9660]( "Wikipedia - ISO 9660")

Corrected command

genisoimage -R -o mydvd.iso "$1"

Burning data to a DVD or Blu-ray


Make sure that the medium is not mounted when you begin to write to it. Mounting may happen automatically if the medium contains a readable file system. In the best case, it will prevent the burn programs from using the burner device. In the worst case, there will be misburns because read operations disturbed the drive. So if in doubt, do:

umount /dev/sr0

growisofs has a small bug with blank BD-R media. It issues an error message after the burning is complete. Programs like k3b then believe the whole burn run failed. To prevent this, either format the blank BD-R by dvd+rw-format /dev/sr0 before submitting it to growisofs or use growisofs option


Archwiki - Optical disk burning

Burning an ISO image to CD, DVD, or BD

To burn a readily prepared ISO image file isoimage.iso onto an optical medium, run for CD:

cdrecord -v -sao dev=/dev/sr0 isoimage.iso

and for DVD or BD:

growisofs -dvd-compat -Z /dev/sr0=isoimage.iso

for CD, DVD, BD:

xorriso -as cdrecord -v dev=/dev/sr0 -dao isoimage.iso

Other reading

Archwiki - Optical disk drive

Archwiki - Optical disk drive

Debian - Gensisoimage man page

Debian - Gensisoimage man page

Debian wiki - genisoimage and xorrisofs

Debian wiki

Archiving data on Blu-ray discs

Archiving data

Mount an ISO file and Burning it to CD-R/DVD-R/BluRay in Linux

Mount an ISO file and Burning

What is the size capacity of my DVD, Dual Layer DVD or Blu-ray disc?

What is the size capacity of my DVD

Wikipedia ISO9660

Wikipedia ISO9660


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Comment #1 posted on 2024-01-02 21:59:31 by frank

Capacity vs. actual capacity


the difference between the two numbers comes from how the bytes are counted. The bigger number (e.g. 4.7) uses powers of 10, whereas the smaller number (4,37) uses powers of 2.

The former is called Gigabyte, the latter Gibibyte (for binary gigabyte). In essence, 4.7 GB (1000 * 1000 * 1000) equals 4,37 GiB (1024 * 1024 * 1024). Different number, but actually the same amount of bytes. A big cause for this confusion is that Windows shows amounts based on binary calculation, but writes out the ten-based unit names, i.e. it says "4,37 GB", but it should say "4.37 GiB".

There is also a difference between lowercase and uppercase b. Lowercase denotes bits, whereas uppercase stands for bytes (easy to remember: the small letter means the smaller unit).

It's always a joy to listen to your calm speech. Greetings.

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