Repair a Damaged Package System after Ubuntu Dist-Upgrade

Happy new year.

My blog runs on a VM at Hetzner with an Ubuntu LTS system. That means 5 years of support… I was running trusty from 2014, so there should be support until 2019. But not every open source software has given you this promise, just the Ubuntanians. So, support for Owncloud run out last year and I thought that the days between years are a good time to switch to a new version.

Hence, I did two dist-upgrades after another from trusty to xenial and from xenial to the current LTS version bionic (every 2 years a new LTS version is coming out). The first upgrade was “successful” with a lot of need for adaption in the configurations afterwards. Then after everything worked again, I did another upgrade, which failed because of this issue.

You do not want your system showing you such a message during do-release-update.

That is, I had to fix a distro upgrade that failed in between… challenge accepted 🤓.

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Creating an Alpha Channel Video with Final Cut Pro X

Lately, I faced the task to make a long-term-support (LTS) backup of a FCP X “green screen” video project. I had two constraints:

  1. The result should take a “small” amount of disk space, only.
  2. It should be possible to alter background, text effects, image effects and so on without loosing quality.

The original data took about 500GB, because of junk takes. But, I wanted to store 3050GB, only. Unfortunately, we chose to take very long shots, so that it was not easy to remove the junk from the FCP X project file (there are paid solutions for this, but the ones I found do not work with combined clips). Just rendering the video in good quality would solve constraint one (C1), but it is hard to make changes to such a file (C2).

Therefore I chose another road: Render the green screen scene with an alpha channel as one long video, in order to sort the wheat (good video) from the chaff (bad video). Using the original green screen instead of an alpha channel was not an option, since I animated the green screen video channel (e.g. moving it from the left to the right) which added black “letter-boxes”. An easy solution would have been to use the keyer to remove the green screen and add a new one via a green background (i.e., an artificial green screen). This can be rendered to a video and a second keyer can be used after a reimport. But this seemed kind of lame (in terms of unprofessional) to me. I wanted a cool alpha channel video as I have seen it in the making of of several films, with an additional video (channel), which is just black and white containing the alpha information.

So, I googled and there was surprisingly sparse information on this topic. There are some formats that should be able to contain an alpha channel like Apple Animation, Apple ProRes 4444, but they all have in common, that they take an unbelievable high amount of disk space, which violates C1 (and they didn’t work for me…). I didn’t find any HowTo or tutorial in THE INTERNET that could help me.

Challenge accepted. 🤓

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VirtualBox v4.2.18 with Native Hard Drive Partition in Mac OSX Lion

Most of the time you use desktop virtualization, you simply add a virtual hard drive and install a guest operating system (like (K)Ubuntu Linux) in it. But some times – as in my case – you already have another operation system on a partition on your native hard drive. For a mac it’s either via Bootcamp or via something like rEfit enabling you to install a BIOS boot manager like Grub. Since it is kind of uncommon using such an existing partition for desktop virtualization, it is not supported (and documented) so good in the different virtualization solutions.
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Trouble with Black Screen in Parallels Desktop v9 with Linux Guest OS on Native Partition

This post is a follow up to Using Parallels Desktop v9 with Linux Guest OS in a Native Partition. After the successful utilization of an existing Linux installation in Parallels Desktop v9 you might want to install the Parallel Tools, in order to have a much nicer integration of the guest system.

But I had the problem, that right after installing the Parallel Tools for Linux AMD 64: The screen went black after the login, when the video driver had been loaded. So I uninstalled the parallel tools again and uninstalled all nvidia drivers which I had installed for dual boot use. Afterwards I reinstalled parallel tools and everything was fine.

Using Parallels Desktop v9 with Linux Guest OS in a Native Partition

Most of the time you use desktop virtualization, you simply add a virtual hard drive and install a guest operating system (like (K)Ubuntu Linux) in it. But some times – as in my case – you already have another operation system on a partition on your native hard drive. For a mac it’s either via Bootcamp or via something like rEfit enabling you to install a BIOS boot manager like Grub. Since it is kind of uncommon using such an existing partition for desktop virtualization, it is not supported (and documented) so good in the different virtualization solutions.
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Exception Handling for Injection Interceptor

Remember my post “Circular Injection of Util Classes in EJB 3.0“? There I offered a some kind of ugly solution to the circular dependency problem for managed classes in Java EE 5. In a preceding post (Circular Dependencies of Session Beans) I grumbled about the exception handling in jBoss-5.1. It lets you alone with a meaningless error message and you have to guess what the problem is. Unfortunately my own code presented in the former post is even worse, since it logs problems but ignores them. It wasn’t mentioned for productive use, but it was annoying to me, so here is a little tune up adding exception handling and readable error messages.
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Inject CDI beans into Tapestry-5.x e.g. in Jboss-7.0.2-Final

As I explained in “Inject Java EE Beans into Tapestry-5.x“, the AppModule offers a way to configure Tapestry Web Applications directly in Java. In that post, we injected Java EE Beans into Tapestry applications. This time we do the same with Context and Dependency Injection (CDI) Beans. It follows the same procedure. The only difference is the way of looking up a bean. We still use JNDI for a lookup, but this time we retrieve the CDI BeanManager. In a second step we get the bean. For performance reasons we retrieve the bean only once per Thread (see annotation @Scope). It will be cached for subsequent lookups.
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CDI and Transactions e.g. in JBoss-7.0.2

In Java EE applications you are safe to consider that every method in a session bean has an associated transaction, since there is an implicit declaration of the transaction attribute required. If you like to change this behavior you have to configure this proactively by adding the annotation @TransactionAttribute with another value (see enum TransactionAttributeType). Context and Dependency Injection (CDI) does not have such an implicit declaration and no direct container managed support for transactions. But it has a very nice realization of the interceptor concept. This post shows, how to facilitate an interceptor in order to add a transaction to every (or a selection) method in a CDI bean, if it does not already exist. This is the default behavior of required.
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