DevOnLinux

Yesterday evening in my free time I’ve made the beautiful paper Tux represented below, thanks to great guide posted on DigitalKamera.

Nerd is the way.
Another penguin is live.

Another great initiative from the Linux Foundation: free training webinars.
Just signup here and wait until first start date.
The first webinar will be dedicated to community collaboration: “How to Work with the Linux community“.
How suggested by this news it will be available on 1st of March, 2010.

A little shell script that I’ve used to generate the list of page composing a given site

#!/bin/bash
if [ "$#" -eq 2 ]
then
wget -erobots=off --mirror --delete-after --reject .jpg,.png,.gif,.swf,.css,.js,.txt,.pdf,.rtf,.odt,.doc $1 2>&1 |grep $1 |cut -d " " -f 4 |cut -d "?" -f 1 | sort | uniq > $2
rm -rf ${1#http://}
else
echo "Usage: ./scriptname http://testsite outputfile"
fi

Save with a desired file name and give it a chmod +x and then just launch from shell:
./scriptname http://testsite outputfile

Just a quick post about tesseract, a quite good solution for OCR under GNU/Linux (specifically Ubuntu Karmic Koala).
First install it trough apt-get
sudo apt-get tesseract-ocr
Install also your preferred language (in my case eng -> tesseract-ocr-eng and ita -> tesseract-ocr-ita).

Ok, we are ready to do some text recognition…
But, under Karmic Koala, there is a problem with tif image as reported by myself here: https://bugs.launchpad.net/ubuntu/+source/tesseract/+bug/461177
The problem is due to a transparent alpha layer that some tif images have (investigation needed here…*), so before do text recognition is necessary to eliminate it, elsewhere tesseract will generate an empty file…
Just install imagemagick and from a shell do this steps:
convert inputimage.tif inputimage_tmp.pbm
convert inputimage_tmp.pbm inputimage_ok.tif
Original solution founded here.

Now we are finally ready to launch tesseract on our tif image.
Just do
tesseract inputimage_ok.tif outputfile
and tesseract will generate outputfile.txt with recognized text.

ps. The packaged version under karmic is 2.03 and not the last one, 2.04, that, as advised on this page, fixed it. So if you prefer, remove old version and install the new version from source.

* Solved. In Gimp is possible to remove the alpha layer. Just go to
Layer (Livello) -> Transparency (Trasparenza) -> Remove alpha layer (Rimuovi canale alpha)

Great article by Colin Guthrie, a Pulseaudio hacker (read it as developer), about the actual state of sound stack in GNU/Linux.

Many improvements are done to ALSA and now the code is better and cleaned in the kernel driver while the userspace library it’s rather complex, for backward compatibility. Pulseaudio, the sound server, go forward, and manage some new requirements of an actual multi-user, multi-source desktop environment, like, quote Colin:

• Software mixing
• Independent (per-application) volume control
• Dealing with permissions (is the user allowed to access the sound device?)
• Dealing with Bluetooth devices
• Dealing with Network based devices (UPnP, Apple Airtunes, Native PulseAudio etc).
• Handling the moving of streams between outputs.
• Handling sound from remote applications run via X11 over a network.
• Dealing with routing policy (Music goes to USB speakers, Desktop sound events to built in speakers, VoIP to Bluetooth headset)
• Effects to promote HCI (e.g. positional event sounds  – button clicks etc, coming out louder on the left hand speaker when triggered from the left hand side of the desktop)
• Power Consumption and Efficient savings.
• Reduces risk of buffer under-runs.

So, GNU/Linux users stay calm and contribute everyone in your manner to the FLOSS world.
Also the sound stack is an a good state