The UDF Standards fall under an ISO Specification.

In many of my postings, I have erroneously described ISO and UDF File Systems as being mutually exclusive. In fact, UDF is also known as ISO-13346, while what I was referring to as ‘Legacy ISO’, is actually known as ISO-9660.

Among other things, this means that software engineers were correct all along, to store UDF File System Images in .ISO-Files.

Only, my own habit of storing them with file-names that end in .UDF, will prevent my desktop-manager from offering to open these, with applications only compatible with ISO-9660.



UDF-Capable Disk Burning with K3b and Debian / Stretch

According to This earlier posting, I was using a Debian / Jessie laptop, the first part of which is also known as Debian 8, to burn UDF-Capable Blu-ray Disks, given an external Blu-ray burner, and that version of Linux required help. Specifically, I needed to modify the way K3b behaves, by uninstalling the package ‘wodim’, which provides ‘cdrkit’, and by custom-compiling ‘cdrtools’, which is meant to act as a drop-in replacement for ‘cdrkit’, except for the fact that for the moment, ‘cdrtools’ was more powerful than ‘cdrkit’.

Under Debian / Stretch, which is also known as Debian 9, ‘wodim’ is not suggested by ‘K3b’ anymore, but rather a required dependency, for which reason to uninstall ‘wodim’, would also uninstall K3b. And so I needed to know, whether the package-provided version of K3b, and all its dependencies, could still burn Blu-rays via the GUI.

And the short answer is that Indeed, under Debian / Stretch, the packaged software has the required capabilities, so that to try to modify the behavior of K3b ( v2.0.3 ) is not only a bit risky, but totally unnecessary.

I created a Data-DVD Project – which we would also do for Blu-rays, and then burned that onto a DVD+R with 3 sets of options:

  1. File System = “Linux+Windows”, back-end = ‘growsiofs’
  2. File System = “UDF”, back-end = ‘growisofs’
  3. File-System = “UDF”, back-end = ‘cdrecord’

What I next did, was to run the command ‘df -T /dev/sr0′ , after mounting each disk via the GUI, both actions as a regular user. I found that options (2) and (3) both showed up as a “udf” file-system, while option (1) showed up as an “iso9660″ file-system.

This is as much, as custom-compiling ‘cdrtools’ could do for the user. Also, when going into the Programs settings of K3b, the full range of supported back-ends shows up as being available. Using burning-options (3) above, starts out the dialog with “Using Wodim” in the GUI, but all 3 settings still show me in the K3b GUI, “Burning ISO9660 File System”.

(Updated 10/23/2017 :


If this is to be used seriously for burning Blu-rays, then there is something which the user should further know.

Continue reading UDF-Capable Disk Burning with K3b and Debian / Stretch

A Note On Playing Back Commercially-Recorded Blu-rays

Just as it was with DVDs, when movies first started to be distributed in that format, commercially-recorded Blu-ray disks today use an encryption system, which is sometimes referred to as ‘content scrambling’, to prevent people from making unauthorized copies. It’s actually named ‘aacs’.

Experts already know about this, but I’m putting this in layman’s terms for anybody who might not.

Basically, Blu-ray playback-devices have a hidden store of public keys, which the users are not allowed to access, and this time, the company is able to update that store of keys via the Internet, because most Blu-ray players today are also online devices.

Unlike how it is with Blu-rays, the content-scrambling system of DVDs was famously hacked. This means that Linux computers are well-able to play back Movie-DVDs. OTOH, the ability to play back commercial Blu-rays, is mainly unsuccessful on Linux computers, or on any other unauthorized devices, because the content-scrambling which gets used – was never hacked. As long as the encryption continues to work, Linux users and pirates will not be able to play back or rip Blu-rays.

As it stands, the company is able to revoke public keys which it was once using.

This is a shame, because some Linux users might only be wanting to view Blu-ray movies which they purchased and paid for. But the main fear of the industry remains, that as a platform, a Linux computer is more susceptible to an unauthorized copy being made of anything, which that Linux computer would also be able to perform authorized playback of.

Therefore, when I gave instructions on how people can record Blu-rays privately, my assumption was that we would not be using any encryption. I don’t see encryption as being important in any way, for home-movies which people might shoot. But, the Blu-ray folder must nevertheless contain a sub-folder named ‘CERTIFICATES’. In the example I wrote about, this sub-folder will simply remain empty.

Further, the mere use of the Blu-ray (single-layer) disk, as a step-up from DVD+Rs, where a Blu-ray can store up to 25GB of pure data instead of 4.7GB, is unfettered for Linux users to use as they wish. All we need is an external Blu-ray burner, and we’re all set to burn pure data. But as soon as we want to burn something using ‘UDF’, which is the approved file-system of Blu-ray players, the level of difficulty already increases, even though no encryption has been used yet.

(Updated 09/19/2017 : )

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How To Burn Blu-ray Movies using Linux – via the GUI

One project which I had half-installed on my laptop named ‘Klystron’ some time ago, but which was not working, was software that would make the task straightforward to carry out, to burn Blu-ray movies from a Linux computer. Because I finally wanted to get that working, I spent time on this in-depth today.

One fact which many people understand, but few people know how to manage, is that Blu-ray movies are not supposed to be burned using the ISO9660 File-System, nor, with the .ISO-Files typically associated with that FS, that store its images. Technically, Blu-ray movies are supposed to be burned using a File-System called ‘UDF’, and version 2.50 of that preferably. Under certain circumstances, v2.01 of UDF may have to suffice, since Linux support for v2.50 is still lagging.

(Edit 10/19/2017 :

I suppose that one detail which I should have included all along, is that I was doing this on a Debian / Jessie system, which is also known as Debian 8. This is also known as the ‘oldstable’ version of Debian now, just because of technological progress. Therefore, Debian 8 was unable to do certain things, which Debian 9 can do out-of-the-box.

I will explain below, why The patch which I described in this posting, should not be undertaken on a Debian / Stretch system, which is also known as Debian 9, and which would be the up-to-date version of Debian as I’m writing this. )

I will spare the reader a lengthy account of what did not work. In order for this to work, I needed to have the Debian Multimedia Repository installed in my /etc/apt/sources.list , which should be straightforward for other people to duplicate. And my main purpose in having this repository, was to get the package ‘tsmuxergui’, version 2.6.11 . In addition, I was working with ‘K3b’ , v2.0.2 .


‘tsmuxergui’ is a GUI-front-end for ‘tsMuxer’, which is a program that can be used to set up Chapters and other playback details, as well as the 1920×1080, H.264-compressed video files of course, that are supposed to make up the program on the final Blu-ray.


As my burner, I used the external ‘Pioneer BDR-XD05′, that connects via USB 3.

There is one additional component which I needed, before K3b was willing and able to burn the UDF File System required, which it is not able to do out-of-the-box:

An out-of-tree version of ‘cdrecord’ , v3.02a7

According to its authors, the versions of cdrecord that have been placed in the standard repositories belongs to ‘cdrkit’, not ‘cdrtools’, and cdrkit fails to provide the back-end, which K3b would need to burn UDF. Yet, to try to perform a binary install of the out-of-tree version, would have been very dangerous to my system. So what I did, and what I would urge other people to do, is to use one of the source-code (tarballs) from above.

First, if the reader has ‘wodim’ installed from the package-manager, I would recommend uninstalling that, just to make sure that package-version-binaries are not overwritten by the out-of-tree versions. Then, I used the above source-code, to custom-compile ‘cdrtools’.

(Edit 10/19/2017 :

If the reader is using Debian / Stretch. aka Debian 9, then the above precaution should fail. The reason for this is the fact, that under Debian / Stretch, K3b depends on ‘wodim’. Therefore, telling the package-manager to uninstall ‘wodim’, will most probably also cause the uninstallation of ‘K3b’.

Now, I can think of several reasons for which Debian Maintainers might have made K3b to depend on ‘wodim’ in Debian Stretch. One possibility, is that they might just not like this patch being applied.

But it seems to be confirmed to me – according to this test – that under Debian / Stretch, K3b is able to burn UDF / Blu-ray File-Systems out-of-the-box. And what that would mean is that to apply this patch is neither required nor desired. )

The nice feature about this version, is that it does not even install itself to ‘/usr/local/bin’. Instead, it installs its binaries to ‘/opt/schily/bin’ , when we finally give the command ‘make install’ with root privileges, so that the ultimate risk of messing up the system is small.

(Updated 10/23/2017 : )

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