Remove DRMs from Kobo’s KEPUB format

1 Nov

Kobo decided to go the proprietary Digital Restriction Management (DRM) way by providing some ebooks bought on their platform in their in-house Kepub format. This means that they can only be read on a Kobo device.

You might have noticed that, when trying to copy an ebook from your Kobo device to your desktop Calibre library, it tells you it can’t do that because the book is “virtual”.

You can actually remove the DRMs from that format by using a plugin called Obok, part of the great DeDRM toolbox provided by Apprentice Harper.

  1. Download the latest obok_plugin.zip file from GitHub;
  2. Open Calibre (if you don’t have this amazing ebook management app already, install it);
  3. Install the plugin: `Preferences > Plugins > Load plugin from file`;
  4. Use the Obok plugin with your device plugged in: select the problematic Kepub ebook(s) and let it do its magic. You can now copy the ebook to your library without those pesky DRMs!

Learn more about the Kepub format on wiki.mobileread.com.

This was tested with Calibre 2.71, Obok DeDRM 6.5.3 and a Kobo Touch with its software at version 3.19.5761.

Fix PGP error NO_PUBKEY when apt-get updating

28 Oct

It is common to find that a  sudo apt-get update does not do a clean job because of a couple of missing public keys. You might get something of the type:

W: GPG error: <a href="http://ppa.launchpad.net">http://ppa.launchpad.net</a> trusty InRelease: The following signatures couldn't be verified because the public key is not available: NO_PUBKEY 8BAF9A6F

Usually, it is possible to directly fetch the missing public key from a popular key server like Ubuntu’s:

sudo apt-key adv --keyserver keyserver.ubuntu.com --recv-keys PUBKEY

… where PUBKEY is replaced by the right identifier in your warning message.

That is usually enough and concludes with gpg: Total number processed: 1

However, if the key is not found on the server, you might have to look for it yourself. For example, in the case of the following error:

W: GPG error: http://download.opensuse.org  Release: The following signatures couldn't be verified because the public key is not available: NO_PUBKEY F2AA0B1E5EF8303B

… the missing key was not available on the Ubuntu key server. I had to first check what exactly the problematic source’s URL looked like, which you can do by either using your distribution’s updater’s GUI (for example, Muon Update Manager > More… > Advanced … > Configure software sources), or by finding it in /etc/apt/sources.list or /etc/apt/sources.list.d/. In my case, the URL was http://download.opensuse.org/repositories/home:/antonbatenev:/tox/xUbuntu_14.04/, which is where I navigated to in my Internet browser to find a Release.key file.

Once you have downloaded that key, you can use the following command to add it to your keyring:

sudo apt-key add Downloads/Release.key

(Make sure you replace Downloads/Release.key with the right path/name.)

Now, you should be able to re-run sudo apt-get update and not run into any warning!

Add missing icons in Ring client

14 Sep

You might have noticed that your Ring desktop client (in my case, the ring package for an Ubuntu 14.04-based distro, version 20160908.1.07d3d92~dfsg1-1 at the time of writing, launched with the gnome-ring command) is missing some icons and shows a red “forbidden” sign instead.

Missing icons in Ring client

Missing icons in Ring client

I fixed that by simply installing a missing dependency called gnome-icon-theme-symbolic. You can do that by executing the following command in a terminal:

sudo apt-get install gnome-icon-theme-symbolic

Close and re-launch the client and the icons should be restored.

Fix two conflicting versions of Keybase

8 Sep

Not having updated keybase in a while (since 0.8.23!…), I ran into an issue after trying to get the latest version (1.0.17) as described on the website: an apt-cache policy keybase would tell me that I had the most recent version installed, whereas running keybase version would return the older one.

The problem is that keybase went from Node.js to Go, and the install method changed. The older version I had installed created a binary in usr/local/bin whereas the new version installed it in usr/bin.

You can see if that is your case by running the two following commands:

/usr/bin/keybase version
/usr/local/bin/keybase version

They should return different versions.

To fix that, you need to uninstall the older version with the following command:

sudo npm uninstall -g keybase

Then, run run_keybase and you should be good!

Install HWSD Viewer on an Ubuntu 14.04-based system

17 Aug

The Harmonized World Soil Database (HWSD) is a 30 arc-second raster database put together by a consortium of organisations: FAO, CAS, IIASA, ISRIC and JRC. It is a monumental collection of data about soil from all around the globe, and is therefore an important tool for researchers.

You can download the raw data or  visualise it on ISRIC’s online viewer, but there is a (closed-source) viewer app specially created to visualise, browse and query the data offline, the “HWSD Viewer”, which unfortunately was only developed for Windows.

To make the viewer work on and Ubuntu 14.04-based system (like KXStudio 14.04, but probably many other OS), you need to:

  1. Make sure you have Wine installed;
  2. Install the viewer, using the binary accessible from this FAO page;
  3. Install the missing runtime libraries thanks to Winetricks, with the following command:
winetricks jet40 mdac28

That should sort you out!

Specifically, what the Winetricks command resolves is:

  • The error message “This setup does not support installing on this operating system.” when trying to install MDAC from the Microsoft website;
  • The error message “Provider cannot be found. It may not be properly installed.” when the software realises Jet40 is not available.

HWSD viewer

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Gallery

Multi-rate HEVC with x265 for adaptive HTTP streaming

15 Aug

Another in-depth look into multi-rate video encoding by my friend Damien Schroeder.

damienschroeder

Version 2.0 of x265 has recently been tagged. It has been more than two years of work since version 1.0. Since then, HEVC has become more visible with wide adoption on devices and in software. From a streaming perspective, adaptive HTTP streaming is now the most common streaming technology to watch live or on-demand content on the web, for example with the DASH standard.

Remember, adaptive HTTP streaming requires a video to be encoded at different representations, that is, different qualities, which is generally achieved by encoding the same video at different (spatial) resolutions and different signal qualities. Depending on the encoder and on the encoding mode, the signal quality can be tuned by varying the quantization parameter (QP), or varying the target bitrate when using rate-control. In the case of x265, the so-called constant rate factor (CRF) can also be used to tune the quality of the…

View original post 1,183 more words

Fnac.com vous emprisonne en rendant la suppression de compte fastidieuse

5 Jul

J’ai récemment créé un compte sur Fnac.com afin de télécharger quelques ouvrages en format EPUB, sans DRM (il y a quelques titres disponibles dans leur catalogue). Malheureusement, comme beaucoup, je n’ai pas lu les conditions générales de vente avant de faire ça.

En effet, après avoir réalisé que mon compte n’allait pas m’être d’une grande utilité, j’ai décidé de le supprimer (j’essaie de conserver une liste des comptes que j’ai créés sur Internet, et de les supprimer rapidement s’ils ne vont plus (ou peu) m’être utile dans le futur). Quelle n’a pas été ma surprise quand j’ai vu qu’ils demandent aux utilisateurs de leur envoyer une copie d’une carte d’identité ou d’un passeport pour supprimer votre compte et vos données de leurs serveurs. (Voir l’article 14 de cette section ou l’explication dans la page d’aide dédiée.)

J’ai horreur de ce genre de pratiques, qui à l’évidence existent seulement afin de rendre extrêmement difficile la suppression d’un compte, pour que vous décidiez au final d’y rester, contre votre grès. Les conditions générales de vente stipulent que cela est conforme à la « réglementation en vigueur » mais il me semble que cela ne s’applique pas nécessairement à la simple suppression d’un compte en ligne.

Voilà ce qui m’a été dit lorsque j’ai demandé la suppression de mon compte par e-mail :

Conformément à la réglementation en vigueur, votre demande de clôture doit être signée et accompagnée de la photocopie de votre pièce d’identité portant votre signature.

Merci également de nous préciser une adresse postale pour la réception de votre réponse qui arrivera sous un délai maximum de 2 mois.

Quelle pratique d’un autre temps ! Je crée un compte en deux seconde sur leur site, puis pour le supprimer je dois leur écrire une lettre, leur fournir une pièce d’identité et attendre qu’ils me disent si ça leur plaît par voie postale ??

La démarche de désinscription est décrite sur plusieurs sites, dont me-desinscrire.fr et moncompte.info. Des commentaires indiquent qu’ils conservent également des données après la suppression, et que c’est une des seules entreprises à exiger une pièce d’identité. Est également justement évoquée le risque que vos documents d’identité soient volés en chemin.

Mon conseil : ne créez pas de compte sur Fnac.com, et si vous en avez déjà un et qu’il ne vous sert pas, supprimez-le en précisant que ces pratiques sont abusives.

Mise à jour (2016-07-11) : après m’être plaint de la difficulté de la démarche, et avoir demandé que l’on me communique la « réglementation en vigueur » à laquelle ils font référence, j’ai reçu un e-mail du service client pour me notifier de la suppression / désactivation (les deux termes sont utilisés de façon inconsistante à différents endroits) de mon compte, malgré le fait que je ne leur ai pas envoyé les documents d’identité demandés. Preuve selon moi qu’ils n’en ont pas vraiment besoin, et que c’est uniquement destiné à vous garder contre votre grès.

 

 

LibreOffice 5.1 becomes “still”, time to upgrade

28 Jun

If you haven’t done so already, it is the right time to upgrade to the LibreOffice 5.1 branch given that, with the release of the 5.1.4 version a few days ago, this branch becomes the “still” (i.e. more stable and secure) branch. Plus, the 5.0 branch reached end of life back in May, which means there won’t be any security fixes any more.

The 5.1 branch brings exciting new features (full release notes here), including:

  • Improvements to formula wizard (Calc)
  • New commands to add rows and column (Calc)
  • New statistics dialogue for calculating regressions (Calc)
  • PNG export (Calc)
  • Many improvements to formula engine (Calc)
  • Reorganised mode selection (Impress)
  • New “equalise” command for shapes (Impress, Draw)
  • Restart counter from presenter console (Impress)
  • Four new transitions (Impress)
  • Import MathML from clipboard (Math)
  • Improved trend line (Chart)
  • New and improved import/export filters (which means better format compatibility)
  • Reorganised menus
  • Lots of sidebar improvements (new sidebar, reorganised items, new buttons and icons…)
  • Special characters in spelling dialogue

On an Ubuntu-based system, you can upgrade to 5.1 by using the following commands in a terminal.

If you already had a PPA installed, remove it. For example, for the 5.0 PPA:

sudo add-apt-repository --remove ppa:libreoffice/libreoffice-5-0

Remove LibreOffice entirely:

sudo apt-get purge libreoffice*

Add the new PPA:

sudo add-apt-repository ppa:libreoffice/libreoffice-5-1

Update your repository info:

sudo apt-get update

Finally, install LibreOffice from the new repository:

sudo apt-get install libreoffice

That’s it!

Note: If you are on Linux Mint, your LibreOffice version might be “pinned” and you will need to do a bit more to upgrade. See this post for example. You might also need to install re-install libreoffice-gnome for it to look right.

Fix different locales being used in terminal output on Ubuntu 14.04(-based) distros with KDE

22 Jun

I was having an issue with a number of different languages being used simultaneously, and in a seemingly random fashion, in my terminal output (and in other apps), on my KXStudio 14.04 install. I remember having played around with locales a while ago, but I could not figure out how to go back to my terminal using only one language.

After searching for a bit, and figuring that /etc/default/locale wasn’t the source of the issue, I found that I had to edit ~/.KDE/env/setlocale.sh for it not to conflict anymore. It was specifically the following line that contained a bunch of different languages:

export LANGUAGE=en:fr:es:de

I replaced the series of language codes with the same value as the other lines, en_GB.UTF-8 in my case:

export LANGUAGE=en_GB.UTF-8

Save the script, and restart your computer. You should be good!

Hopefully this saves a few people some pain!

More on languages: this AskUbuntu question.

 

Install Clementine 1.3 on Puppy Linux Tahrpup 6.0

16 Jun

I installed Puppy Linux for the first time, on my old decaying netbook that serves as a music station. Puppy Linux is more than a distro, it is a multi-faceted Linux project that experiments with different concepts. It also is a solution for resuscitating an old computer as it is very light and snappy for a number of reasons. The stock audio player Guayadeque is a great app, but I was missing my good old Clementine for the network remote feature.

On the Ubuntu 14.04-based Tahrpup 6.0 version, the stock version of Clementine is quite outdated. To install the more recent Clementine 1.3, you will need to get the right DEB installer from the Clementine website (the one packaged for Ubuntu 14.04, in its 32-bit architecture version), execute it, and then resolve the missing dependencies.

On my fresh install, the missing dependencies were:

  • libprotobuf
  • libechonest
  • libglew
  • libgstreamer-plugins-base1.0
  • liblastfm
  • libfftw3
  • libcrypto++

To install them, you can use Puppy’s PPM tool located in “Menu > Setup”, search them and click one on each of them to add them to the list of packages to install. You just need to click on “Do it!” when you have them all listed.

A way to check for package dependencies is to use the built-in tool “Check dependencies installed pkg”, accessible from “Menu > Setup”.

After that, Clementine should run, but if you get a crash when trying to play a track, you might want to also install the following gstreamer 1.0 plugins in order to decode most formats:

  • gstreamer1.0-plugins-good
  • gstreamer1.0-plugins-bad
  • gstreamer1.0-plugins-ugly