Drawing arrows with GIMP

Today I desperately needed to draw arrows in a picture to point parts of an Arduino stack with an Ethernet and Xbee shield.

So, I took the picture of the stack, increased the contrast and made other adjustments to perfect the pictures, and I was ready to place the arrows. Arrows? How? OK, I googled and found this http://registry.gimp.org/node/20269

You just have to download the .scm file. If you are a Linux user (obviously I use Fedora), go to your Home Folder and press Control+H to unhide the hidden folders. Next, go to the “.gimp-2.6” (1st: Yes there is a full stop, 2nd: 2.6 is the name of the folder right now according to GIMP’s current version). Inside this folder find the folder “scripts” and place there the .scm file. Now, open GIMP (or re-open if already running), go to Tools and you are good to go 🙂

(Tip: To draw an arrow you must use the path tool at the toolbox. Just click one time to point the start of the arrow and a second time to point the end. You will just make a straight line that will be used as a path)

In Greek : Στον σύνδεσμο που υπάρχει παραπάνω μπορείτε να κατεβάσετε το .scm αρχείο που θα σας επιτρέψει να σχεδιάζετε βέλη με το GIMP αυτόματα. Για να λειτουργήσει το αυτό το script πηγαίνουμε στο Home Folder, πατάμε Control+H για να αποκαλυφθούν οι κρυφοί φάκελοι και στη συνέχεια πηγαίνουμε στον φάκελο “.gimp-2.6″ (1ον ναι υπάρχει τελεία, 2ον το όνομα προέρχεται από την τωρινή έκδοση”). Μέσα σε αυτόν τον φάκελο υπάρχει ο φάκελος “scripts” όπου και τοποθετούμε το .scm αρχείο. Ανοίγωντας το GIMP τώρα μπορούμε να δούμε στο Tools το Arrow 🙂

(Συμβουλή: Για να φτιάξετε το arrow πρέπει να σχηματίσεται ένα μονοπάτι με το path tool. Αν απλά κάνετε ένα κλικ για την αρχή και άλλο ένα για το τέλος του βέλους εκεί που επιθυμείτε είστε έτοιμοι να φτιάξετε το βέλος με το Arrow που βρίσκεται στα Tools)

GFOSS Conference 2010

Yesterday ended the GFOSS Conference 2010 that took place in Athens at NTUA (National Technical University of Athens). It was an event that started on Friday, but yesterday was special because of the workshop I was organising this week together with Anastasis (anast)! The subject was (in translation) “Fedora Project : Remix and Spin it! The Fedora operating system you own (and not only that)”. Furthermore, we also had booth presence on both days with the usual swag 🙂

The workshop lasted 1 hour ( the schedule said 2 hours) but I think something more than that would be boring. Some setbacks occurred previously that day and affected the workshop a little bit. First, I tried to create an iso image using a kicksart file I made that unfortunately needed a bit of time to be created due to yesterday’s bad signal of the wifi where the booth of Fedora was (damn near fields), so I didn’t make it in time for the “Takis OS” Live CD I wanted to create. Second, I didn’t expect my laptop to fail me when I tried to plug in the dvi cable. I count it as a setback but, ok I overcame it thanks to the laptop of Anastasis 🙂

I think it was around 15 people that joined the workshop (thanks to everybody). I tried to pass the knowledge of what is a remix, a spin, their differences (and similarities), guidelines, processes, kickstart files, livecd-tools, cobbler…but not to the extent of getting down with too much coding, configurations and setting many arameters. In a few words I tried to show the way for a simple creation of a Remix from the kickstart file until the creation of a LiveCD and told a few words about the magic things cobbler can do. Anastasis talked about Geo Spin and Security Lab spin. I couldn’t miss the chance to talk about Fedora Electronic Lab too. Also, I am happy that Nikos (comzeradd) and Pantelis (pant) joined us as well!

click for more photos

Openfest 2010 @ ΤΕΙ Πειραιά (the recap)

Μετά από πολύ καιρό λοιπόν, επιστρέφω στον κειμενογράφο του wordpress. Αυτό το post θα το αφιερώσω όμως αποκλειστικά στο event της προηγούμενης εβδομάδας, στο Openfest 2010 που διεξήχθει στο ΤΕΙ Πειραιά και διοργανώθηκε από το τμήμα Ηλεκτρονικών Υπολογιστικών Συστημάτων του ΤΕΙ (αξίζει ένα μεγάλο μπράβο σε όλους τους). Ως γνωστόν είμαι φοιτητής του τμήματος Ηλεκτρονικής αυτού του ιδρύματος και έτσι δεν θα μπορούσα να λείψω. Ένιωσα επίσης και το χρέος να κάνω μια παρουσίαση, φυσικά για το Fedora!

Έτσι και έγινε. Μια εβδομάδα περίπου πριν το event και είχαμε ήδη αρχίσει να ετοιμαζαστε. Εκτυπώσεις, σχεδιασμός για αφίσες, εγγραφές cd, ποτήρια Fedora κτλ. Σε όλη αυτή τη διαδικασία, από την αρχή μέχρι το τέλος του Openfest, βοήθησαν οι συνήθεις ύποπτοι του Fedora (που δεν είναι μόνο όσοι αναφέρονται στο wiki).  Είχα και την χαρά να φιλοξενήσω τον Σαλονικιό μας τον Χρήστο Μπαχαράκη (cmpahar) για κάμποσες μέρες  ( μας λύπεις ρε! 😀 ).

Εν συντομία, είχαμε το καλύτερο booth του event. Απλά και αντικειμενικότατα παρακαλώ 🙂 . Η παρουσίαση έχω την εντύπωση ότι δεν πήγε άσχημα. Μπορούσα και καλύτερα αλλά θα με δω στο video που θα ανέβει στο openfest.teipir.gr και θα σας πω. Επί τη ευκαιρία, να διορθώσω μια γκάφα μου : το F13 βγαίνει με βάση το πρόγραμμα 11 Μαΐου (και όχι 11 Απριλίου). Έπρεπε να κάνω το fail μου και εγώ δεν άντεξα . Ακολουθεί φωτογραφικό υλικό, ετοιμαστείτε 😛

Ελληνική Ομάδα Fedora
El Fedorato (click για να θαυμάσετε περισσότερες)

Να ευχαριστήσω θερμά και από εδώ τον Πιέρρο και την Θάλεια, τον Αναστάση και την Εβελίνα, τον Χρήστο, τον Παντελή (15 χρονών και ορεξάτος ορεξάτος) και όλους όσους συμμετείχαν.

Κάτι άσχετο,να σας ενημερώσω πως πέρα από το identi.ca γράφω και στο twitter . Kάτι σχετικό, θα ακολουθήσει και post εις την αγγλικήν με το video της παρουσίασης γιατί ακόμη δεν έχει βγει. Ευχαριστώ.

Use your Nokia cellphone for presentations

Today I didn’t have many things to do (“You have to do the laundry” sais the little angel on my right shoulder, “Yeah…Whatever” says the little devil on my left) so I checked out what Google has to offer me (as a Fedora user) now that I am at the mercy of the internet. I checked out Picasa, Google Reader, Google Desktop and amora (not a google app). I am sure you are familiar with the 3 first ones. But the last one may not ring you any bell…If you own a Nokia cellphone actually, you should know it (and yes, I allow you to check the link before you finish reading this post 🙂 ). I own a Nokia N82, and amora offers me the means to controll my computer via my mobile’s keyboard (mostly for presentations though).

To install amora I also had to install Python for S60 first (for N82 I found this one and works fine). It’s so cool! I tried it with OOo Impress and works great! 🙂  I can’t wait to use it!

To install any google application on fedora you have to follow this guide : first configure the rpm key and then configure yum .

By the way I couldn’t launch picasa because I have to intsall the 32-bit openssl package! damn…Not in the mood to fix it 😛

Google Reader works fine (also Google Reader notifier) . ActualIy, I was using the RSS plugin for Evolution, which is not bad, but now I don’t have to wait for all the feeds to get updated to read my mail properly.

Google Desktop? I don’t think I will ever use it as Firefox is open as long as my notebook is switched on.

edit : amora is simply hosted inside google-code (I didn’t make that clear enough). It was implemented by Adenilson Cavalcanti a developer from “Instituto Nokia de Tecnologia” (Nokia Institute of Technology – Brazil).(thanks to Ademar)

I’m flying with Firefox

Well, first of all, my find-something-bad-to-make-you-downgrade period for Fedora 11 is over and the results are as expected…using my computer on daily bases is a procedure that leveled up. But the beauty of it is that you know you are using free software. Software that is shared to you and belongs to you thanks to other people that believe in freedom. And then you say “hey! maybe I should contribute” because that’s your way to say thank you and learn stuff. That’s how I feel to be honest. So, just because I use Firefox every day for many hours, I decided to say thanks this time by contributing as a Test Pilot 🙂 . OK, I admit that I am also curious to see how this whole thing is going to work. I also can’t hide that I want to be a package maintainer for Fedora, but I have lots in my mind right now.

Furthermore, the last 3 days I try to focus on wireless sensor networks which of course means my familiarization with TinyOS and other technologies which are extremely cool. There is the need of great effort from my part though. Anyway, networks ,electronics and applications that can be used for HCI …no need to ask for more 🙂

I almost forgot CHECK THIS OUT: academicearth.org when I first saw it I tried not to behave like the men at the recent Heineken commercial (cheering like crazy). Thanks Christos!

Fedora 11 released and me being busy.

OK. Now that I have the chance to take a break from studying, I can finally make a post. I’m in the middle of my exams period.

First of all, I’m writing from my clean-installed Fedora 11 x86_64 system :). You have to see it boot. Everything seems to work just fine. I just forgot to save my bookmarks :P. But! After the installation I didn’t forgot to yum groupinstallElectronic Lab‘ .

I am looking forward to start a project suggested from my professor at the TEI.  It will concern low power microcontrollers for wireless sensor networks. And guess what…it will be open source !!! (I just found out about uClinux and this) After my exams period I will try to find out how this can be combined with Fedora. Furthermore, maybe there is a chance I will do a little research (or something like that, I don’t know for sure yet) on HCI systems in collaboration with the University of Athens on February. I hope this will come true :). We’ll see.

I’m also getting ready for my studies at Barcelona, at the Facultad de Informática de Barcelona of the Universitat Politécnica de Catalunya  (UPC), I was accepted as an Erasmus student for the next semester. I’m in search of a place to stay. Single rooms with wifi and my own WC are hard to find though. I hope I’ll make it. I will also look forward to meet guys of the local Fedora community there. It’ll be fun.

To be honest I wanted this post to be for my presentation at NTUA which went well, not as many people as I expected. But hey! We never give up, and we always try to become even better. The presentation lasted for 1 hour and I tried to be as much prepared as possible. It’s not easy when you are a pre-graduate student of electronics to talk about VLSI systems etc. I am still waiting for photographic material to post.

Παρουσίαση του Fedora Electronic Lab στο ΕΜΠ

Το Fedora Electronic Lab αποτελεί μία από τις μεγάλες προσπάθειες ένταξης της free & open source ιδεολογίας στον χώρο του hardware.

To FEL είναι ένα Fedora Spin, μια συλλογή foss ΕDA εργαλείων που έχει ως στόχο την βελτιστοποίηση της ροής του σχεδιασμού των hardware projects. Ενώνει τον κόσμο του free & open source software με τον κόσμο του hardware.

Αφορά τους τομείς :

  • της μικροηλεκτρονικής (VLSI)
  • του σχεδιασμού και της εξομοίωσης αναλογικών/ψηφιακών/mixed κυκλωμάτων (spice, pcb και άλλα εργαλεία CAD)
  • τον προγραμματισμό ICs (PICs, FPGAs, προγραμματισμός με VHDL/Verilog)
  • τον σχεδιασμό ενσωματωμένων συστημάτων
  • της διαχείρισης projects.

Η Κοινότητα Ελεύθερου Λογισμικού του ΕΜΠ σε συνεργασία με τον Fedora-el διοργανώνει μια παρουσίαση του Fedora Electronic Lab. Στην παρουσίαση θα γίνει περιγραφή των στόχων και των χαρακτηριστικών του FEL καθώς και παρουσίαση ορισμένων προγραμμάτων του. Η παρουσίαση θα γίνει την Πέμπτη 4 Ιουνίου στις 3 το μεσημέρι στο MOΠ (cc.ece.ntua) Γενικές Έδρες Κτίριο Β Δεύτερος Όροφος από τις σκάλες αριστερά.


FossComm 2009 : recap :)

Friday 8/5 was  quite a busy day. After I finished my courses  etc. and once again I headed for home through the hell that has been renamed to “national road” at mid-day (all thanks to my fellow Greeks who crash their cars every now and then).  Anyhow, when I finally arrived home I picked up my Fedora and FEL (Fedora Electronic Lab)  leaflets, my laptop and everything else I needed to go to FossComm 2009 along with Pierros and friends.

Well, the trip was fine and we had a stop at Volos for a bit greek meze and a little bit of tsipouro. Afterwards we went to Larissa , got to the Hotel and relaxed in our rooms. I also met there my friend Alexandros. Anyways, Friday was not as interesting as Saturday.

Next morning we were at the TEI of Larissa to prepare our booth for Fedora for the whole event (along with Christos Bacharakis, Thalia Papoutsaki and Pierros) ! We unpacked everything, from fliers to OLPC, plus I had my laptop to show some programs on FEL. All guys there did a great job organizing the event. The atmosphere was relaxing and also exciting.

I can’t describe how the night went. Α word that could describe most of the people that attended the feast at the tsipouradiko (tavern with lots of tsipouro and greek meze dishes) would be “kurumpelo” which means drunk, but I believe we were more or less drunk but very joyful and in a great mood for company. (But seriously, I have no idea how the guy with the bicycle ended up safe at his house…)

FossComm attendies, presenters, organizers etc all together :)
FossComm attendies, presenters, organizers etc all together 🙂

Now, let’s talk about Sunday 🙂 .  Pierros Papadeas ‘s presentation on the Fedora project went really well! He really made clear of the goals, the people that support it, explained the four foundations etc…It was cool. Dimitris Glezos presented Transifex. For those who don’t already know, it’s an open source project, a localization web platform already used by the Fedora Project (Dimitris is a member of th Fedora Board!) and Red Hat, developed by Dimitris and the rest of  Indifex ‘s (yeap, his company) engineers team.

My presentation on FEL went quite good. It happened during our Fedora 11 Hackfest. I had to point out the goals of FEL, some interesting features that has and that will have (thanks Chitlesh!). I also presented some very interesting tools for design and simulation of circuits. I also mentioned the advantages of FEL, live every other Spin of Fedora has. It was my first presentation and the audience was not very into electronics (except to 2 out of 20-25 people). I had to try not to become boring, so I had to make changes instantly to what I previously prepared to say. Not the best feeling but at the end it was fun and I gained a great experience.

On Monday the Fedora 11 Hackfest continued but I was absent due to a lab at my school I had to attend.

For even more interesting photos and videos —-> FTP Server of Linux Team

I’m glad this post is over because there’s a lot more that I have to post. Busy week, busy month, busy year…

My self at FossComm 2009 - FEL presentation
My self at FossComm 2009 - FEL presentation

FOSDEM (the summary)

The previous weekend was exciting and fun. I was at FOSDEM 2009 at Brussels (of course), not just to attend the various talks, but also to be present as a Fedora Ambassador at the Fedora booth. There are lot’s of names to mention, as the main benefit from such events is that you get to know people who always have something interesting to say.There is always more knowledge to gain.

More about my experience at the booth. As you may see in various photos of the booth, we had a lot of swag. Many of that stuff  (Fedora flyers, FEL flyers, buttons) were brought by the greek Fedora Ambassadors who attended the event, which is Pierros Papadeas (he really deserves most of the credit) and myself. No, I didn’t forget of Dimitris Glezos who was busy due to his Fedora and Indifex related plans!


Well, after a pleasant flight with Olympic Airlines, 6 greek open source guys were ready for action in Brussels. I couldn’t wait for the beer event which, eventually, was awesome. The Delirium Cafe was full of people. Most of the time (except when I had go and buy me a beer) I spent it on the outside talking with folks. Anyway, that’s what many other people did. The place was crowded 🙂


We tried to get to FOSDEM  as soon as possible with the addition of 3 greek guys we expected.  The booth was already set up. We placed the swag we brought. Our laptops were ready for people who wanted to try Fedora 10.

Most of the questions people had was about the OLPCs and the Sugar interface, but we did the best we could to promote Fedora to future contributors. Time went by and I couldn’t miss the chance to attend the RPM Packaging talk of Christoph Wickert, nor the Fedora Electronic Lab talk of Chitlesh Goorah. Both were great (you may see for your self at the links).

Me at the Fedora DevRoom
Me at the Fedora DevRoom

To be honest, at the FEL talk I got my self embarrassed. Something really funny happened. During his talk Chitlesh asked “Who doesn’t know what a LiveCD is?”. Instead of that I heard, “Who knows what a LiveCD is”. And guess what, I raised my hand and , of course, I was the only one. I explained immediately that I didn’t understand the question. The irony is that, as a Fedora Ambassador, I give hundreds of these cds and as a Linux user, there was no chance I wouldn’t have used one 😛 .

So, later on I was present at Max Spevack’s speech. I really liked the way he got his points clear with the “Red Hat employee” vs “Fedora contributor” approach, using (or not using) a Red fedora. Unfortunately, I couldn’t be there all the time. I had to return to the booth.

Oh yeah! I also got my Fedora Ambassadors shirt (thanks to Joerg Simon). Plus, I couldn’t resist not getting some of the Mozilla buttons and other swag, a FOSDEM and a GNOME t-shirt.

The night was interesting as well. Most of the Fedora guys , we went to another beer cafe. Chitlesh recommended a Kwak. Great beer, strange glass (the next morning I got my self one of those glasses). We had an interesting discussion about lots of things concerning Fedora.


The Fedora booth
The Fedora booth

An other day with lots to happen and lots to do. The combination of booth attendance + interesting talks was a bit tiring but I love to get tired this way. I attended the key-signing party which took place outside the building. It was freezing but we got the job done. There, I met a Spanish Debian guy. I tried to talk a little spanish, but after he started talking I couldn’t understand a thing. Lucky me he translated. I also went to the MediaWiki talk and  to the “Ruby and Java” talk, so I could get to know Ruby a little better.

When the night came, we went to the Delirium Cafe for once more (I could spend a year there).

Pierros, George and me spent Monday for exploring a little bit of Brussels.

Overall, a fantastic experience. Even more pictures here!