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Thursday, September 22, 2011

More videos


Two inches to the right via mubix:

Jane Austen's Fight Club via Wondermark:

Jane Austen's Fight Club from Keith Paugh on Vimeo.

Sink The Bismarck:

Storm - a beat poem:

Wednesday, September 21, 2011

Of maps and men


A very cool visualization of the imigration / emigration data:

To remember: the relative sizes of countries / continents on most maps is not representative of the true ratios, because most map projections were not meant for that. If you want to play around with different projections, here is a nice page from Wolfram (unfortunately you have to install a ~100MB plugin to get it to work). If you need the raw data, just go to Wikipedia.

Finally, here is a good essay from Asimov (from 1989) about the scientific process: The Relativity of Wrong - small nitpick: it would have been even better if it had used the metric system or at least it didn't switch from miles to inches in he middle of the essay.

Informative videos about copyright and remixing issues


Walking on Eggshells: Documentary about Remix Culture - via the comixtalk blog:

Internet is Freedom - a speech given by Lawrence Lessig at the Italian Parlament - via the Security4All blog:

PBS: Copyright Criminals - while the video is not online, you can watch the trailer and listen to some remixes inspired by it which are under a CC license.

And just as a bonus: a cynical video about filtering the Internet - via the IT Law in Ireland blog:


The History of Copyright Law - via the laughing squid:

TED Johanna Blakley: Lessons from fashion's free culture

Update: it seems that I already posted the last video - admittedly I'm becoming senile with the advance of the years :-)

Tuesday, September 20, 2011

Recording test performance with Jenkins


In many (most?) systems performance is an important non-functional requirement. And even if you attained the required performance, it is useful to keep an eye on it to detect if a codechange involuntarily deteriorates it. Enter the Performance plugin for Jenkins. Using it you can record the performance (as in: speed of execution) of your test runs and set alter thresholds which cause the build to fail. Also it can generate graphs like the one below:

To do this:

  • Have Jenkins installed
  • Intstall the Performance plugin (or upgrade to the latest version, since there was a bug in earlier versions which prevented the parsing of the JUnit reports)
  • For your build check “Publish Performance test result report” and add locations where the reports should be collected from.
  • That’s it! Future builds will collect the performance data and you can access it using the “Performance Trend” link (at the job level) or the “Performance Report” link (at the build level)

More details / caveats:

  • The paths are defined as ANT file expressions (that is you can use “**” to specify an arbitrary level of directories, for example: target/surefire-reports/**/TEST*.xml)
  • JUnit performance is grouped at the test-class level, thus it probably makes sense create separate project / module which group the performance test cases.
  • Benchmarking is hard and JUnit doesn’t give you any provisions to do warmup or to repeat the tests multiple times. To make your test as relevant as possible you should do this manually (warmup code can be placed in the @Before method for example). A properly set up JMeter task accounts for this already.
  • TestNG tests can also be parsed as long as the test run is set to produce a JUnit compatible report.
  • Slightly off-topic: to integrate a JMeter run into your maven build, you can use the AntRun plugin:
           <taskdef name="jmeter" classpath="C:\work\ant\lib\ant-jmeter-1.1.0.jar"
           <jmeter jmeterhome="C:\jakarta-jmeter-2.5\"

Article originally posted to the Transylvania JUG blog.

Audio quality redux


Yet an other example for how simple steps can improve the audio quality considerably. The clip below is taken from this blogpost (which I originally found trough Hacker News). You can find the processed version here, or use the controls below to do a quick A/B comparison of the two. The processing was very simple (1. noise removal and 2. running trough the Levelator) and quick.

Crossfade (Original - New):

PS: For people reading the post trough an RSS reader: you probably need to click trough to the site to see the comparison in action, since most (all?) RSS readers filter out javascript for security reasons.

PS: If you are interested in the simple script which was use to interact with the two youtube players, you can find it in my code repository.

Sunday, September 18, 2011

Power Line Humm Removal With Audacity


As a response to George Starcher's Removing Power Line Hum from Audio with GarageBand I would like to post a quick tutorial on how to do the same with Audacity:

Friday, September 16, 2011

Protein Shakes site review


This is something new for me: protein shakes. Medically I can't offer advice about it (I'm weary about using foreign substances not recommended by a specialist), but the site certainly is has some positive signs:

  • The badges at the bottom are clickable and they go to the respective sites which certify the site
  • The domain is registered since 2006 and they are paypal verified since 2007
  • They have an active Facebook and Twitter account
  • They use paypal / google checkout for payment which reduces your risk considerably

They also have also some less positive signs:

  • There is no physical contact address
  • The registration details are hidden by proxy registration
  • The phone-number is a generic one (I would have liked one which coincides with the physical location)

All in all I would recommend this site for small purchases from inside the USA (they don't deliver internationally). Also, I would consult a doctor (or multiple doctors) about the possible effect of the substances. In my view (and I'm no doctor) this is more serious than the homeopathic or "natural" substances and it should be handled with care. Then again, I'm also against medicine / medical devices (like glasses) being sold in places without expert supervision (like supermarkets).

Full disclosure: this is a paid review from ReviewMe. Under the terms of the understanding I was not obligated to skew my viewpoint in any way (ie. only post positive facts).

Tuesday, September 13, 2011

Running JRuby on 64 bit Windows


Usually it is as simple as: download, install, run. You can run into problems however if you have both the 32 bit and 64 bit JVMs installed (which is quite often) because it will try to use the 32 bit JVM. You can check which JVM is being used from the command line:

jruby --version
jruby 1.6.3 (ruby-1.8.7-p330) (2011-07-07 965162f) (Java HotSpot(TM) 64-Bit Server VM 1.7.0) [Windows 7-amd64-java] # 64 bit
jruby 1.6.3 (ruby-1.8.7-p330) (2011-07-07 965162f) (Java HotSpot(TM) Client VM 1.6.0_26) [Windows 7-x86-java] # 32 bit

To work around this issue, specify the JVM to use in your jruby.bat (or other batch files installed by gems like vagrant.bat) explicitly. Example jruby.bat:

java -Djruby.home=C:\jruby-1.6.3 -jar  -jar "C:\jruby-1.6.3\lib\jruby.jar" %1 %2 %3 %4 %5 %6 %7 %8 %9

Example vagrant.bat

java -Djruby.home=C:\jruby-1.6.3 -jar "C:\jruby-1.6.3\lib\jruby.jar" "C:/jruby-1.6.3/bin/vagrant" %1 %2 %3 %4 %5 %6 %7 %8 %9

Using less with syntax highlight


You can use vim as your pager and obtain two benefits: syntax highlight and access to all the advanced commands (like search). You can do this under ubuntu by adding the following line to your ~/.bashrc:

alias less='/usr/share/vim/vimcurrent/macros/'


  • You have to have vim installed (which doesn't come by default, but it is as simple as sudo apt-get install vim-nox)
  • It supports viewing directly bz2 and gz archives as well as pipe input from stdin (but in that case it fails sometime to highlight)
  • Edit commands (like dd) are disabled, so you can't accidentally modify the file you are viewing

Friday, September 09, 2011

Link love


Here are a couple of close friends' blogs. They are just starting out writing, but hopefully giving them some link love will encourage them to write even more great content. Without further ado, in no particular order:

Tuesday, September 06, 2011

100 years of style


A very entertaining video in the style of Evolution of Dance:

Hattip to

Quick'n'dirty Mediawiki file crawler

URL='' MIME='image/jpeg' \
  bash -c 'wget -q -O - "$URL/wiki/index.php?title=Special:MIMESearch&mime=$MIME&limit=500&offset=0" \
  | grep -Po "\/wiki\/images[^\"]+" \
  | xargs -n1 -I {} wget "$URL{}"'

What it does: it uses the "MIME search" functionality on the wiki to locate files of a certain mime type and then xargs+wget each of them.


  • A maximum of 500 files are downloaded
  • Downloads are not parallelized, thus slower than they could be

Monday, September 05, 2011

Creating a non-MAC bound CentOS 6 machine


I was building VMs to be deployed with Vagrant / Virtualbox for our QAs and discovered that on new instantiations of the machine the networking interface wasn't coming up. The problem was that Virtualbox was assigning a random MAC address to the NIC (and rightly so, to avoid conflicts). I used the following steps to solve this:

  1. Remove the HWADDR line from /etc/sysconfig/network-scripts/ifcfg/eth0
  2. Delete the file /etc/udev/rules.d/70-persistent-net.rules (hat tip)

These two steps are specific to CentOS 6 (on 5.x the first step is sufficient). Also, the second if is recreated at the next boot, thus after rm-ing it, you should shut down the machine and package it (not start it again, or if you do, you should remove the file again).

Thursday, September 01, 2011

Levant Digital Marketing review


Levant Digital Marketing is a company which does Search Engine Optimization in the Middle East. They seem to be a very new company (the domain was registered in January of 2011). They are part of "JHG Holding", but this itself is also only from 2009 (and their site contains minimal content). I didn't manage to find their headquarters on Google Maps either (but this might just be an issue with Google Maps in foreign countries). Their phone number is indeed from Lebanon (as their physical address is). Their facebook page is non-existent at the moment (was it deleted?) and the twitter account is completely empty.

All in all, while I couln't find anything explicitly negative about them, it is more the case that I couldn't find anything concrete about them :-). As far as advice goes, when starting out you are better off with some simple steps, and when you grow you might consider looking into a SEO consultancy, but take care to find a reputable one rather than a cheap one or one which promises you the moon.

Full disclosure: this is a paid review from ReviewMe. Under the terms of the understanding I was not obligated to skew my viewpoint in any way (ie. only post positive facts).