About Playing Back Non-DRMed Content

I have run across the idea several times, that unknown people in the Industry, wish to block the users’ ability to create Non-DRMed content – that being either Video-DVDs or Video-Blu-rays – and to play back that content on standard playback-devices.

According to my own experiences, this idea is an unsubstantiated rumor. In addition to such a measure seeming pointless – wanting to block content of which nobody claims intellectual ownership – in every case I’ve encountered myself, there was some sort of technical bug or incompatibility, arising from the actual data and its formats.

In my experience, playback devices do what my computers do, which is to play back content as best their logic allows, as long as the content is Not DRMed. Just as with computers, the logic of these machines does not always follow ‘Human Common Sense’.

What this also suggests, is that the description is largely hype, according to which UDF content urgently needs to be of version 2.50 . Higher UDF versions do serve a purpose, but that purpose was never meant to be, to restrict access to technology. Accordingly, I still find the concept plausible, that many consumers have content on Hybrid ISO9660 / UDF 1.02 disks, even if those disks were bought in a store, and that standalone playback-devices simply play them.

Dirk

 

A Word Of Warning about Using tsMuxer And Certain UDF Versions

I have written numerous postings, to guide myself as well as anybody else who might be interested, on the subject of Video-DVD burning, as well as on the subject of Video-Blu-ray burning. According to advice which I gave, it’s possible to use a program named “tsMuxerGUI”, to create the Blu-ray File Structure, which a Blu-ray playback-device will play.

According to additional advice I gave, it’s possible to burn these Blu-rays using some version of ISO-13346, which is also known as ‘UDF’, as opposed to burning them with ISO-9660, as the File System with which data is encoded on the disk.

But what I have noticed, is that certain Blu-rays which were burned in this way, will not play back using the application “VLC”. Normally, the open-source player named VLC can play back Blu-rays, which were commercially produced. So, it would seem natural, that we’d want to test our Blu-rays on the computer we used to create them, with the VLC application as the playback system.

My own experience has been, that the Blu-rays which result play back fine on my Sony Blu-ray playback-device, but do not open on VLC, on my computers.

As unlikely as this may seem, I did after all return to the conclusion, that I’ve created two UDF-encoded Blu-rays, which VLC cannot read, because of the customized UDF-encoding.

Apparently, when we instruct VLC to play a disk inserted into a specific Blu-ray drive, such as perhaps ‘/dev/sr1′, VLC expects to connect directly with the drive, rather than to use the mount-point exclusively, which Linux can create for us.

This is somewhat bewildering, because by default, I need to mount the disk in question, as a regular user, which we can do from the notification tray, before VLC is capable of playing it. But then, whether VLC can in fact read the Blu-ray turns into an independent question, from whether Linux was able to mount it for the rest of the computer to use.

(Edit 10/23/2017 :

There is an even more improbable-sounding possibility, as to why this actually happens. It may be that VLC expects to be able to access the Media Key Block of an inserted Blu-ray Disk, in order to decrypt that, and to start playing back DRM-ed Blu-rays. This would require not only raw access to the disk, but also that such a Block be present on the disk.

If I translate this problem into Human Logic, I’ll get, that ‘VLC’ is only capable of playing Blu-rays that have DRM, when those Blu-rays are also ISO9660-compatible. This may be unfortunate, because even though UDF 2.50 is still not ‘the law of the land’, ISO9660-compatibility may be phased out one day, while DRM likely will not be. )

But there is a workaround. VLC includes in its menus, the ability to Play A Directory. We can choose this option, and can navigate to the mount-point, which we created when we mounted the disk from the notification tray. That mount-point should exist under the directory ‘/media’ , have ‘BDMV’ as one of its sub-folders. And when we then direct VLC to play the folder, that is the parent folder to the ‘BDMV’ sub-folder, we are in fact directing it to play the root-folder of the disk.

And in my own, recent experience, VLC is then able to play the disk. I specifically took care, not to direct VLC to play the folder on my HD, from which I created one of the Blu-rays, but rather the folder that is the mount-point of an actually-inserted disk. Because, it would be pointless to conduct a test, which physically bypasses the disk.

Continue reading A Word Of Warning about Using tsMuxer And Certain UDF Versions

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.

Dirk

 

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 :

screenshot_20171023_173754

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