Saturday, July 12, 2014

GetBack GPS 0.3 is released

Get the latest version on F-Droid.

Arrow pointing to destination and compass indicating North

GetBack GPS v0.3 is now available. It adds a realtime compass and detects your travel direction. This way the arrow pointing to your destination will still point in the right direction, even when travelling backwards.
And there are some small UI improvements.

The app is now also available in Danish, Brazilian Portuguese, Traditional Chinese and French. A big thanks to the translators and supporting services!

A complete list of features and available languages is available on the website.


Friday, July 11, 2014

Remove bars from Android screenshots

How to remove the Status Bar at the top and return/home/screens button bar on the bottom/side from Android screenshots, using commandline ImageMagick.

Portrait screenshot

Command :

convert -size 1080x1920 -extract 1080x1700+0+75 original_screenshot.png screenshot_after.png

1080x1920 is the original size of the image (portrait)
1080x1700 is the new size, +0+75 the x and y offset where the extraction starts
(sizes may differ if you have a phone with a different screensize and resolution)


Result:
Original portrait screenshot, before cropping
After cropping

Landscape screenshot

Command :

convert -size 1920x1080 -extract 1792x1005+0+75 original_screenshot.png screenshot_after.png

1920x1080 is the original size of the image (landscape)
1792x1005 is the new size, +0+75 the x and y offset where the extraction starts

(sizes may differ if you have a phone with a different screensize and resolution)


Result:

Original screenshot (landscape), before cropping

After cropping

Monday, June 23, 2014

File recovery using foremost

Quick note on using foremost to retrieve files from a harddrive with a faulty partition table :

sudo foremost -dT -i /dev/md2 -t jpeg -o /path/to/restore2/

This scans /dev/md2 hd, looking for jpeg files and puts the restored files in /path/to/restore2/
Foremost can retrieve a lot of different file types (including images, MS Office files, PDF's and zipfiles), look at the man pages for a complete list. It is also possible to define your own filters.

Modify (or copy first) the foremost.conf file and add a line  for every file type fe. :

ex1   y   4096000  \x50\x4b\x03          \x74\x78\x74
ex2   y   4096000  \x50\x4b\x03???\x44   \x74\x78\x74

where you specify :
  • file extension
  • case sensitive pattern (if ASCII codes are used in the pattern)
  • maximum size of a file in bytes
  • starting pattern
  • end pattern
The pattern can be in hex code or ASCII, use a ? as a wildcard for one character. In the second example above, a wildcard for 3 characters is added.

Now run foremost, using the custom config file :


sudo foremost -dT -i /dev/md2 -c /tmp/foremost.conf -o /path/to/restore2/

This scans /dev/md2 hd, using the rules in /tmp/foremost.conf and puts the restored files in /path/to/restore2/

Thursday, March 06, 2014

Google Summer of Code 2014 meetup at Ghent University

Wednesday evening, March 5th, 19u, about 30 students of Ghent university (Belgium) showed up for an info session about Google Summer of Code 2014. Some of them already heard about it, but for most of them it was new.

Google Summer of Code is a yearly initiative of Google, this year held for the 10th time, to introduce students in higher education to Open Source development, by offering them a stipend of 5500 USD for 12 weeks of coding on an Open Source project during the summer. It gives the students realworld experience, writing code that will be used by many users worldwide, collaborating with the teams of the Open Source organisation they will contribute to, improving their teamwork and communication skills.

After a brief introduction about the program, 4 (of the 190 selected for GSoC 2014) Open Source organisations presented themselves.

Sage is an Open Source collection of mathematical tools, ranging from solving differential equations to plotting functions. Some of their projects this year focus on improving the user interface, but there is also a need for adding mathematical tools, fe. for knot theory.

GNU Octave is also related to mathematics, but is mostly used for simulations and numerical computations. Their ideas pages contains several projects, one of them is adding a library for doing finite element simulations.
Both these projects are interesting for students with an affinity for maths and programming, but also for students wanting to improve the GUI or add other supporting tools.

Next up was the phpMyAdmin project, a webbased user interface for MySQL databases. Having participated to GSoC for many years, the list of projects to work on range from improving the AJAX error reporting tool that was added in GSoC 2013, to also report PHP errors, over a tool to normalize and check the structure of a database to interface improvements. If you are proficient in PHP or JavaScript and interested in databases, one of these projects might be for you.

MuseScore was the last project to present itself. It is a free and Open Source music annotation software, but there is also a version for tablets and an online music sheet library to share your compositions. Their ideas for this year's GSoC range from support for visually impaired users to tools for adding lyrics to a music score. Interested students should be proficient with C++ and Qt.

All projects mentioned that communicating with the development team and the mentors, using either the IRC channel or the mailing list is very important and the best way to get into contact with them.

At the reception afterwards, the mentors of the Open Source projects talked to the students answering their questions about GSoC, on how to apply, how to write a good proposal, and many more question that are also answered in the GSoC FAQ.

Thanks to the Open Source organisations (SAGE, GNU Octave, phpMyAdmin and MuseScore) for their talks and sharing their experience, and to the student associations (VTK, Zeus WPI, Ceneka) and UGent for their help in organising the event.

Sunday, February 09, 2014

An impression of FOSDEM 2014

Sunday evening, 19:30, leaving Brussels by train, heading home.
48 hours earlier I arrived here for FOSDEM : another amazing weekend of Open Source, sharing knowledge, meeting people, getting new ideas, geekiness, and well, also a bit of beer.

Opening talk of FOSDEM 2014
Opening talk of FOSDEM 2014
With more than 500 talks and presentations spread over 2 days in 22 rooms held at the ULB in Brussels, with 5-10 thousand visitors, it is impossible to attend and see everything. Luckily, thanks to an amazing team of origanisers and volunteers everything went smoothly and all talks are recorded and the videos will be available soon.

Some highlights, some inspiration and some ideas to work on :

Tuesday, January 21, 2014

going to FOSDEM 2014

It's FOSDEM 2014 again in two weeks time. And I'm looking forward to it : attending lectures, meeting people, talking about Open Source, ...

After having a quick look at the schedule with more than 500 (!) lectures over a period of a weekend, I made a selection of interesting talks, because obviously, it is impossible to attend them all :

Wednesday, January 01, 2014

This was 2013 and plans for 2014!


It's this time of the year again, reviewing the cool things that happened, learning from the stuff that didn't go as planned and adjusting the goals of last year accordingly.

2013 was busy, here are some achievements :
  • visited FOSDEM 2013 and did a talk on phpMyAdmin
  • visited Newline 0x03
  • co-organised a GSoC info session at UGent
  • first Wagner experience : Parsifal, long but musically beautiful
  • phpMyAdmin is accepted as a mentoring organisation for GSoC 2013 and has 6 students. I'll be a co-mentor and co-org admin this year
  • got promoted to a higher pay grade
  • did a citytrip to Berlin, visited LinuxTag 2013 and moderated a few sessions. I've also got some ideas for my Android app while attending the Android session.
  • finished a few yellow routes at Bleau.
  • did some outdoor rock climbing in Fontainebleau.
  • did a presentation introducing Latex to my colleagues.
  • visited Debconf13 held in Vaumarcus, Switzerland, were phpMyAdmin had a team meeting and did a phpMyAdmin tutorial.
  • went to GSoC Mentor Summit 2013 at Google Headquarters, Mountain View, California, organised a Key Signing Party and  a session on international acceptance of Open Source licenses.
  • did some climbing in Yosemite National Park
  • released GetBack GPS, my first Android app
  • prepared sabayon for the first time.
  • made more than 2000 contributions (commits and created issues) in one year on github.
  • travelled to the Philipines.
Check out my plans for 2014 :
  • Android app development : After releasing an Android app this year for the first time, I plan to explore this path a bit more. Improving the GetBack GPS app a bit more, I still have some ideas as you can see on the roadmap, getting some more experience on automated testing, test driven development (TDD), Java and object oriented programming along the way.
    Another Android project for this year will use Bluetooth communication, in a small project I will work on with a friend.
  • Bouldering/climbing : Last year I started climbing in the gym and I did some outdoor climbing as well. I utterly enjoy this, so I definitely want to spend some more time on it. Hopefully with some outdoor climbing trips during the upcoming year.
  • Visit FOSDEM and LinuxTag.
I'm looking forward to an exciting year.
I wish you and your family the same, with good health and successful projects.