Hi guys, Last summer, I got into an interesting course entitled Emerging topics in information technologies . During the first part of the course, we focused more on 3D computer vision techniques and how to manipulate 3D images.Issues such as depth-image-based rendering were obscure and captivating enough to get me motivated throughout the summer semester. In order Continue reading Interesting project : Render stereoscopic 3D images using Kinect 2.0

Mind versus body: time perception Since mid-April I'm playing a new game. It's really awesome, and I learned some surprising things. The game Zwift is quite different from the games I'm usually playing. While it does have all or most of the elements of a game, more precisely an MMO, the main point of the game if physical exercise (in the real world). The in-game performance if the result of the (again, real-world) power output. Playing the game is more or less like many other games: very nice graphics, varied terrain (or not), interaction, or better said competition, with other players, online leader boards, races, gear "upgrade" (only cosmetic AFAIK), etc. The game more or less progresses like usual, but the fact that the main driver is body changes, to my surprise, the time component of the game. For me, with a normal game let's say one of Bioware's Dragon Age games, or one of CD Red's Witcher games a short gaming session is 2-3 hours, a reasonable session 6-8 hours, and longer ones are for "marathon" gaming sessions. Playing a good game for one hour feels like you've been cheated one barely starts and has to stop. On Zwift, things are different. A short session is 20-30 minutes, but this already feels good. A good one is more than one hour, and for me, the longest rides I had were three hours. A three hour session, if done at or near Functional Threshold Power (see here for another article about it), leaves me spent. I just had today such a long ride (at around 85% FTP) and it took me an hour afterwards (and eating) to recover. The interesting part is that, body exertion aside, the brain sees a 3 hour Zwift equivalent to an 8-10 hour gaming session. Both are tiring, and the perception of passed time is the same (long). Same with shorter sessions: if I do a 40 minutes ride, it feels subjectively as rewarding as a 2-3 hour normal gaming session. I wonder what mechanism is that influences this perception. Is it just effort level? But there's no real effort (as in increased heart rate) for computer games. Is it the fact that so much blood is needed for the muscles when cycling that the brain gets comparatively little, so it enters slow-speed mode (hey, who pressed the Turbo button)? In any case, using Zwift results in a much more efficient use of my time when I'm playing just to decompress/relax. Another interesting difference is how much importance a good night sleep has on body performance. With computer games, it makes a difference, but not a huge one, and it usually goes away a couple of hours in the game, at least subjectively. With cycling, a bad night results in persistent lower performance all around (for me at least), and one that you easily feel (e.g. for max 5-second average power). And the last thing I learned, although this shouldn't be a surprise: my FTP is way lower than it's supposed to be (according to the internet). I guess the hundreds of hours I put into pure computer games didn't do anything to my fitness, to my "surprise". I'm curious to see, if I can keep this going on, how things will look like in ~6 months or so.

About a week ago, I extended vcswatch to also look at tags in git repositories. Previously, it was solely paying attention to the version number in the top paragraph in debian/changelog, and would alert if that version didn't match the package version in Debian unstable or experimental. The idea is that "UNRELEASED" versions will keep nagging the maintainer (via DDPO) not to forget that some day this package needs an upload. This works for git, svn, bzr, hg, cvs, mtn, and darcs repositories (in decreasing order of actual usage numbers in Debian. I had actually tried to add arch support as well, but that VCS is so weird that it wasn't worth the trouble). There are several shortcomings in that simple approach:

• Some packages update debian/changelog only at release time, e.g. auto-generated from the git changelog using git-dch
• Missing or misplaced release tags are not detected

The new mechanism fixes this for git repositories by also looking at the output of git describe --tags. If there are any commits since the last tag, and the vcswatch status according to debian/changelog would otherwise be "OK", a new status "COMMITS" is set. DDPO will report e.g. "1.4-1+2", to be read as "2 commits since the tag [debian/]1.4-1". Of the 16644 packages using git in Debian, currently 7327 are "OK", 2649 are in the new "COMMITS" state, and 4227 are "NEW". 723 are "OLD" and 79 are "UNREL" which indicates that the package in Debian is ahead of the git repository. 1639 are in an ERROR state. So far the new mechanism works for git only, but other VCSes could be added as well.

Book reading is happening, and more book review posting will be happening. I'm a bit behind in writing reviews, but the holiday weekend is a good opportunity to do a bit of catching up. In the meantime, here are some new acquisitions: Roxanne J. Coady & Joy Johannessen (ed.) The Books That Changed My Life (nonfiction)
James S.A. Corey Caliban's War (sff)
James S.A. Corey Abaddon's Gate (sff)
Max Gladstone Full Fathom Five (sff)
Max Gladstone Last First Snow (sff)
N.K. Jemisin The Fifth Season (sff)
Guy Gavriel Kay Children of Earth and Sky (sff)
Naomi Novik Uprooted (sff)
Ada Palmer Too Like the Lightning (sff)
Graydon Saunders Safely You Deliver (sff)
Neal Stephenson Seveneves (sff)
Jeff VanderMeer Annihilation (sff) This is mostly catching up on books that were nominated for awards. I want to read the (legitimate) nominees for Hugo best novel this year if I can find the time, and VanderMeer won the Nebula last year. The rest of Gladstone's series to date was on sale, and I really liked the first book. And of course a new Guy Gavriel Kay is buy on sight. I'm currently re-reading The Sarantine Mosaic, since I read that before I started writing reviews and Children of Earth and Sky is apparently set in historical contact with it. (It's possible all of Kay's historical fantasies are set in the same universe, but they're usually fairly disconnected.)

Puppet 4 has been uploaded to Debian unstable. This is a major upgrade from Puppet 3. If you are using Puppet, chances are that it is handling important bits of your infrastructure, and you should upgrade with care. Here are some points to consider.

Read Puppet s upgrade checklist First, there are a number of changes in Puppet itself. There is an upgrade checklist for Puppet (the software) published by Puppet (the company). Please read this before you upgrade, and not after.

Using exported resources? In Puppet 4, using exported resources requires PuppetDB, which is not packaged in Debian.

Getting PuppetDB Puppet provides good installation documentation for PuppetDB, and an apt software repository where you you can get the packages you require.

Editor support packages The packages vim-puppet and puppet-el provide support for editors Vim and Emacs. These are no longer built from the puppet source package. The sources for these have moved to separate repositories, and will get individual source packages. For vim-puppet, there are two alternatives for new packaging, rodjek/vim-puppet, and puppetlabs/puppet-syntax-vim For puppet-el puppetlabs/puppet-syntax-emacs and lunaryorn/puppet-mode are available.

The first Armadillo release of the 7.* series is out: a new version 7.100.3. We uploaded RcppArmadillo 0.7.100.3.0 to CRAN and Debian. This followed the usual thorough reverse-dependecy checking of by now 230 packages using it. This release now requires a recent enough compiler. As g++ is so common, we explicitly test for version 4.6 or newer. So if you happen to be on an older RHEL or CentOS release, you may need to get yourself a more modern compiler. R on Windows is now at 4.9.3 which is decent (yet stable) choice; the 4.8 series of g++ will also do. For reference, the current LTS of Ubuntu is at 5.3.1, and we have g++ 6.1 available in Debian testing. This new upstream release adds a few new helper functions (which are particularly useful in statistics, but were of course already available to us via Rcpp), more slicing of Cube data structures and a brand new sparse matrix decomposition module courtesy of Yixuan Qiu -- whom R users know as the author of the RSpectra package (which replaces his older rArpack package) and of course all the most excellent work he provided to RcppEigen. Armadillo is a powerful and expressive C++ template library for linear algebra aiming towards a good balance between speed and ease of use with a syntax deliberately close to a Matlab. Changes in this release are as follows:

Changes in RcppArmadillo version 0.7.100.3.0 (2016-05-25)

• Upgraded to Armadillo test release 7.100.3
  • added erf(), erfc(), lgamma()
  • added .head_slices() and .tail_slices() to subcube views
  • spsolve() now requires SuperLU 5.2
  • eigs_sym(), eigs_gen() and svds() now use a built-in reimplementation of ARPACK for real (non-complex) matrices (code contributed by Yixuan Qiu)
• The configure code now checks against old g++ version which are no longer sufficient to build the package.

Courtesy of CRANberries, there is also a diffstat report for this release. As always, more detailed information is on the RcppArmadillo page. Questions, comments etc should go to the rcpp-devel mailing list off the R-Forge page.

This post by Dirk Eddelbuettel originated on his Thinking inside the box blog. Please report excessive re-aggregation in third-party for-profit settings.

A little more than 11 years ago, one of the creators of Tor, and the current President of the Tor project, Roger Dingledine, gave a talk for the members of the Norwegian Unix User group (NUUG). A video of the talk was recorded, and today, thanks to the great help from David Noble, I finally was able to publish the video of the talk on Frikanalen, the Norwegian open channel TV station where NUUG currently publishes its talks. You can watch the live stream using a web browser with WebM support, or check out the recording on the video on demand page for the talk "Tor: Anonymous communication for the US Department of Defence...and you.". Here is the video included for those of you using browsers with HTML video and Ogg Theora support: I guess the gist of the talk can be summarised quite simply: If you want to help the military in USA (and everyone else), use Tor. :)

It has been an exciting first week of my internship. I was able to produce a few patches,
and submitted upstream, as well as into debian packaging. I am hopeful they will get accepted,
preferably upstream so all can benefit! kapptemplate:
https://bugs.kde.org/show_bug.cgi?id=363448
https://bugs.debian.org/cgi-bin/bugreport.cgi?bug=825122 choqok:
https://bugs.debian.org/cgi-bin/bugreport.cgi?bug=825322 However, after speaking with Lisandro ( choqok maintainer ) I decided a better course of action
is to try and fix the actual source of the problem, kconfig_compiler from kde4libs is generating
non utf-8 cpp and header files under certain conditions like an environment that does not have a
locale set. Of course, I have some help with this from wonderful folks in KDE, which is good
because kde4libs codebase is HUGE! So I hope to have two new bugs early next week for choqok. I checked up on my existing kdevplatform bug:
https://bugs.debian.org/cgi-bin/bugreport.cgi?bug=815962 And noticed it has not received attention, so I created upstream bug:
https://bugs.kde.org/show_bug.cgi?id=363615 And updated the debian bug patch DEP 3 with upstream bug url. I have been working on kdevelop-php without success yet, looks like build-id
( I still need to find the source ) and embedded kernel which I think I found,
though I will reach out to my awesome mentor to get some help on this one. I did not knock out quite as many builds as I wanted, but I picked some hard ones
that are new to me So in the end it was a very successful first week, because I
have learned several new things that will help me with future reproducible builds. Have a great weekend.

I just did a bundle upload of all MATE 1.14 related packages to Debian unstable. Packages are currently building for the 23 architectures supported by Debian, build status can be viewed on the DDPO page of the Debian MATE Packaging Team [1] Credits Again a big thanks to the packaging team. Martin Wimpress again did a fabulous job in bumping all packages towards the 1.14 release series during the last weeks. During last week, I reviewed his work and uploaded all binary packages to a staging repository. Also a big thanks to Vangelis Mouhtsis, who recently added more hardening support to all those MATE packages that do some sort of C compilation at build time. After testing all MATE 1.14 packages on a Debian unstable system, I decided to do a bundle upload today. Packages should be falling out of the build daemons within the next couple of hours/days (depending on the architecture being built for). GTK2 -> GTK3 The greatest change for this release of MATE to Debian is the switch over from GTK2 to GTK3. People using the MATE desktop environment on Debian systems are invited to test the new MATE 1.14 packages and give feedback via the Debian bug tracker, esp. on the user experience regarding the switch over to GTK3. Thanks to all who help getting MATE 1.14 in Debian better every day!!! Known issues when running in NXv3 sessions The new GTK3 build of MATE works fine locally (against local X.org server). However, it causes some trouble (i.e. graphical glitches) when running in an NXv3 based remote desktop session. Those issues have to be addressed by me (while wearing my NXv3 upstream hat), I guess (sigh...). light+love,
Mike [1] https://qa.debian.org/developer.php?login=pkg-mate-team@lists.alioth.deb...

There are some news on my packaging work from may:

• OTRS
  • I have updated it to version 5.0.10
  • Also I have updated the jessie backports version from 5.0.8 to 5.0.10
  • I have to test the new issue #825291 (database update with Postgres fails UTF-8 Perl error), maybe someone has got an idea?
• needrestart
  • Thanks to Thomas Liske (upstream author) for adressing mostly all open bugs and wishes from the Debian BTS and Github. Version 2.8 fixes 6 Debian bugs
  • Already available in jessie-backports :)
• geoip-database
  • As usual package updated and uploaded to jessie-backports and wheezy-backports-sloppy
• geoip
  • Someone here interested in fixing #811767 with GCC 6? I were not able to fix it
  • .. and if it compiles, the result segfaults :(
• fglrx-driver
  • I have removed the fglrx-driver from the Debian sid/stretch repository
  • This means that fglrx in Debian is dead
  • You should use the amdgpu driver instead :)
• icinga2
  • After some more new upstream releases I have updated the jessie-backports version to 2.4.10 and it works like a charm :)

Hi guys, Late post before I go to bed. I don t know if you ever heard about Euler problems ? It s a series of challenging computer and mathematical programming problems. They require some thinking in order to be solved. The reason behind solving them is to acquire better skills at problem solving, which is something Continue reading Euler problems

Time for new release! We just updated rfoaas on CRAN, and it now corresponds to version 0.1.9 of the FOAAS API. The rfoaas package provides an interface for R to the most excellent FOAAS service--which provides a modern, scalable and RESTful web service for the frequent need to tell someone to f$#@ off. Release 0.1.9 brings three new access point functions: greed(), me() and morning(). It also adds an S3 print method for the returned object. A demo of first of these additions in shown in the image in this post. As usual, CRANberries provides a diff to the previous CRAN release. Questions, comments etc should go to the GitHub issue tracker.

This post by Dirk Eddelbuettel originated on his Thinking inside the box blog. Please report excessive re-aggregation in third-party for-profit settings.

Hey guys, What are extension methods ? Extension methods are quite simple to understand and they can be quite useful in time of needs. An extension method give you the power to create a new method for any type that you would like. They re static methods designed to extend the capabilities of a type without Continue reading Bring more functionalities to types using extension methods

Today I finally ran a bit outside, for the first time in 2016. Actually, for even longer the first run since May 2015. I have been only biking in the last year, so this was a very pleasant change of pace (hah), even if just a short run (below 4K). The funny thing is that since I've been biking consistently (and hard) in the last two months, my fitness level is reasonable, so I managed to beat my all-time personal records for 1 Km and 1 mile (I never sprint, so these are just 'best of' segments out of longer runs). It's probably because I only did ~3.8Km, but still, I was very surprised, since I planned and did an easy run. How could I beat my all-time PR, even better than the times back in 2012 when I was doing regular running? Even the average pace over the entire run was better than my last training runs (~5Km) back in April/May 2015, by 15-45s. I guess cross-training does work after all, at least when competing against myself

So far the only missing submodule in Debian's Qt5 stack is QtWebEngine. None of us the current Qt maintainers have the time/will to do the necessary stuff to have it properly packaged.

So if you would like to have QtWebEngine in Debian and:

• You have C++ libraries' packaging skills.
• You have a powerful enough machine/enough patience to do the necessary builds (8+ GB RAM+swap required).
• You are willing to deal with 3rd party embedded software.
• You are willing to keep up with security fixes.
• You are accessible through IRC and have the necessary communications skills to work together with the rest of the team.

Open Source Data Center Conference (OSDC) was a pleasure and great event, Netways clearly knows how to run a conference. This year at OSDC 2016 I gave a talk titled Continuous Integration in Data Centers Further 3 Years Later . The slides from this talk are available online (PDF, 6.2MB). Thanks to Netways folks also a recording is available: This embedded video doesn t work for you? Try heading over to YouTube. Note: my talk was kind of an update and extension for the (german) talk I gave at OSDC 2013. If you re interested, the slides (PDF, 4.3MB) and the recording (YouTube) from my talk in 2013 are available online as well.

How to manage your photos? That is probably the biggest question for anyone doing anything with a photo camera. As resolutions of cameras grow, the data we have to manage is growing ever. In my case I am talking about more than 50000 photos and videos measuring up to about 200Gb of disk space, constantly growing. There are several photo management softwares out there, I guess the most commonly used ones are Shotwell for the Gnome desktop, digiKam for the KDE world, and FotoXX. I have not used Shotwell and digiKam for quite some time, and collect here my experiences of strength and weaknesses of the two programs. FotoXX seems to be very powerful, too, but I haven t tested it till now.
There is no clear winner here, unfortunately. Both have their strength and their weaknesses. And as a consequence I am using both in parallel. Before I start a clear declaration: I have been using Shotwell for many years, and have myself contributed considerable code to Shotwell, in particular the whole comment system (comments for photos and events), as well as improved the Piwigo upload features. I started using digiKam some month ago when I started to look for offloading parts of my photo library to external devices. Since then I have used both in parallel. Let us start with what these programs say about themselves: Shotwell is declared as a Photo Manager for Gnome 3, with the following features:

• Import from disk or camera
• Organize by time-based Events, Tags (keywords), Folders, and more
• View your photos in full-window or fullscreen mode
• Crop, rotate, color adjust, straighten, and enhance photos
• Slideshow
• Video and RAW photo support
• Share to major Web services, including Facebook, Flickr, and YouTube

digiKam says about itself that it is an advanced digital photo management application for Linux, Windows, and Mac-OSX. It has a very long feature page with a short list at the beginning:

• import pictures
• organize your collection
• view items
• edit and enhance
• create (slideshows, calendar, print, )
• share your creations (using social web services, email, your own web allery, )

Now that sounds like they are very similar, but upon using them it turns out that there are huge differences, that can easily be summed up in a short statement:

Shotwell is Gnome 3 that means get rid of functionality. digiKam is KDE that means provide as much functionality as possible.

Now before you run after me with a knife because you do not agree with me on the above, either read on, or stop reading. I am not interested in flame wars over Gnome versus KDE philosophy. I have been using Gnome since many years, and tried to convince myself to G3 for more than a year until I threw out all of it but selected programs but their number is going down. Let us look at those aspects I am using: organization, offline, sharing, editing. Organization In Shotwell, your photos are organized into events, independent from their location on disk. These events can have title and comment and collect a set of related photos. In my case I often have photos from two or more cameras (my camera and mobile, photos of friends), which I keep in separate directories within a main directory for the event. For example I have a folder 2016/05.21-22.Climbing.Tanigakadake with two sub-folders Norbert (for my photos) and Friend (for my friends photos). In Shotwell all the photos are in the same event, which is shown with title 05.21-22 Tanigakawadake Climbing within the 2016 year and May month.
So in short Shotwell distinguishes between disk layout and album/event names. In digiKam there is a strict connection between disk layout and album names 1:1. Albums are directories. One can adjust the viewer to show all photos of sub-albums in the main album, and by this one can achieve the same effect of merging all photos of my friend and myself. The good thing in this approach is that one can easily have sub-albums: Imagine a trip to three different islands of Hawaii during one trip. This is something easy to achieve in digiKam, but hard in Shotwell.
Other organization methods Both Shotwell and digiKam support tags, including hierarchical tags and rating (0-5 stars). Shotwell has in addition a quick flag action that I used quite often for initial selecting photos, as well as accepted and rejected. digiKam also has so called picks (no pick, reject, pending, accepted), and colors (not used by now). Both programs have some face detection support, but also this I haven t used. So in the organization respect there is no clear winner. I like the Event idea of Shotwell, or better, the separation of events from the disk structure. But on the other hand, Shotwell does not allow for sub-albums, which is also a pain. No clear winner draw Offline storage That is simple: Shotwell: forget it, not reasonably possible. One can move parts to an external HD, then unplug it, and Shotwell will tell you that all the photos are missings. And when you plug the external HD in, it will redetect them. But this is not proper support, just a consequence of hash sum storage. Also separation into several libraries (online and offline) is not supported. On the other hand, digiKam supports multiple libraries, partly offline, without a hinch. I would love to have this feature in Shotwell, because I need to free disk space, urgently!!! Clear winner: digiKam Sharing Again here my testing is very restricted I am using my own Piwigo installation exclusively. Here Shotwell is excellent in providing support for various features: upload to existing category, create new category, resize, optionally remove tags, add comments to albums and photos, etc. (partly implemented by me
On the other hand digiKam has a very barebone interface to Piwigo you can upload photos to an existing album and resize them, but that is already everything. One also needs to say that the list of supported services in digiKam is by far longer than the one in Shotwell, but the main services (usual suspects) are supported in both.
Clear winner: Shotwell (but I haven t tested other upload services). Editing The editing capabilities of Shotwell are again very restricted: red eyes, resize, levels, .
digiKam here is more like a photo editor software with loads of tools and features. I haven t even explored all the options maybe I can get rid of GIMP, too?
Clear winner: digiKam Conclusions While I am still working with both, I actually would love to move completely to digiKam. I simply cannot stand the Gnome 3 philosophy of reducing functionality to a minimal for dummy users. There is a market for that, sure, but I am not one of it. Unfortunately, the missing Event support, and much more the completely minimal support for Piwigo sharing in digiKam is a big show stopper at the moment. Even after testing the upcoming digiKam 5.0 version for some time, I didn t see any improvement wrt to sharing. That leaves me with the only option to continue working with both programs, and hope to get a new bigger SSD before the current one runs out of space. Of course I could start hacking into the digiKam source maybe I do this when I have a bit more time to add proper Piwigo support.

Hey guys, I won t say yet again that it has been too long because it really was. I ll try to keep my blog updated weekly concerning a program I m doing with Google this summer. It s called the Google Summer of Code (GSoC). Basically, it s meant for students to be able to contribute on an open Continue reading GSoC16: First coding week

The isenkram system is a user-focused solution in Debian for handling hardware related packages. The idea is to have a database of mappings between hardware and packages, and pop up a dialog suggesting for the user to install the packages to use a given hardware dongle. Some use cases are when you insert a Yubikey, it proposes to install the software needed to control it; when you insert a braille reader list it proposes to install the packages needed to send text to the reader; and when you insert a ColorHug screen calibrator it suggests to install the driver for it. The system work well, and even have a few command line tools to install firmware packages and packages for the hardware already in the machine (as opposed to hotpluggable hardware). The system was initially written using aptdaemon, because I found good documentation and example code on how to use it. But aptdaemon is going away and is generally being replaced by PackageKit, so Isenkram needed a rewrite. And today, thanks to the great patch from my college Sunil Mohan Adapa in the FreedomBox project, the rewrite finally took place. I've just uploaded a new version of Isenkram into Debian Unstable with the patch included, and the default for the background daemon is now to use PackageKit. To check it out, install the isenkram package and insert some hardware dongle and see if it is recognised. If you want to know what kind of packages isenkram would propose for the machine it is running on, you can check out the isenkram-lookup program. This is what it look like on a Thinkpad X230:

% isenkram-lookup 
bluez
cheese
fprintd
fprintd-demo
gkrellm-thinkbat
hdapsd
libpam-fprintd
pidgin-blinklight
thinkfan
tleds
tp-smapi-dkms
tp-smapi-source
tpb
%p

The hardware mappings come from several places. The preferred way is for packages to announce their hardware support using the cross distribution appstream system. See previous blog posts about isenkram to learn how to do that.