TronProg: Programming and Computers

After I switched to Kubuntu Natty 11.04, my microphone stopped working (especially in Skype). I tried to adjust the microphone settings in Phonon System Settings, but, besides having too many devices to choose from, that settings dialog seems to have a bug which prevents the preferences to being saved. Not to mention that there is no way to test the input device from that setting dialog!

Luckily, in that bug report I also found the solution to have microphone work!

The solution consists in installing the package pavucontrol, which provides a comfortable PulseAudio Volume Control dialog, which also gives you immediate feedback to see whether the microphone is working, and reduces the number of devices to choose from!

After you installed that package, Skype options dialog presents a button to open that volume control dialog


If you click the button you'll get the pavucontrol dialog, and in "Input Devices" tab you can choose the input device from the list and instantly check whether that's the right device: just speak in the microphone, and see whether the horizontal bar moves while you're speaking.


That's all! Now you're microphone is set correctly. :)

Pubblicato da betto a 11:43 AM 19 commenti

Etichette: audio, kubuntu, natty, skype, ubuntu

I've always recompiled Linux kernel on all my Linux installations, starting from the kernel sources of the Ubuntu repositories. Then I've heard about the famous 200 lines kernel patch, that I wanted to try, but it doesn't seem to apply to ubuntu linux sources (or at least I had this impression), and I didn't want to try the alternatives.

Then I stumbled upon this nice article about using KernelCheck (which I didn't know) to compile the linux kernel (not from the ubuntu repositories):

a graphical user interface program designed to make the kernel-compiling process as easy as the click of a button. KernelCheck will fetch the latest information from http://www.kernel.org, which hosts the source packages for the Linux kernel, and ask the user which one they would like to compile into a .deb package (with the option of installing the kernel after the compilation).

• NOT to select the reconfiguration of X server
• NOT to install the nvidia driver
• to select "apply custom patch to the kernel" (if you want to try the 200 lines patch)
• I prefer not to install the kernel package after compilation: I'll do that myself
  

Pubblicato da betto a 12:50 PM 3 commenti

Etichette: kernel, kubuntu, linux, nvidia, ubuntu

I don't like Gnome and I usually use KDE, but on a specific computer I have to use Gnome, and I noted that after switching to Ubuntu Maverick, icons on eclipse menus were not showing anymore.


I asked on some newsgroups with no luck, then on IRC I was pointed to this bug, which solved my issue :)

You need to enable icons in menus with gnome configuration. You find some ways to do that on that bug report, but I simply ran gconf-editor on the command line, and enabled that checkbox:


Now my icons in menus are back :)

Pubblicato da betto a 3:22 PM 1 commenti

Etichette: bugs, eclipse, gnome, maverick, ubuntu

If you're experiencing this error message at boot in Linux (e.g., after you recompiled the kernel in Ubuntu Lucid)

mounting none on /dev failed: No such device

don't be scared, the boot will continue and there'll be no problem (at least, I read in some posts); I never experienced problems even with this error at boot.
But if you want to get rid of it, just make sure that you have

CONFIG_DEVTMPFS=y

in your .config file of your kernel source directory.

Pubblicato da betto a 3:00 PM 3 commenti

Etichette: kernel, linux, ubuntu

Lately I started to try to develop applications for the Nokia N900, and the Maemo platform uses my beloved framework Qt :)

In particular, Nokia started to develop the Qt-Mobility Framework. Quoting from their white paper:

The Qt Mobility Project presents a collection of related software frameworks and interfaces. The objective being to deliver new Qt APIs for mobile application developers. Using these new APIs, developers will be able to create cross-platform applications targeting Maemo, Symbian and other platforms. This suite of features also has components that will be desirable to all users, not just those with mobile devices, so Mobility has advantages even for the desktop user.

sudo apt-get install libasound2-dev libbluetooth-dev libgstreamer0.10-dev libgstreamer-plugins-base0.10-dev network-manager-dev libxv-dev gstreamer-tools gstreamer0.10-plugins-base gstreamer0.10-ffmpeg w32codecs ubuntu-restricted-extras gstreamer0.10-plugins-good freeglut3-dev

git clone git://gitorious.org/qt-mobility/qt-mobility.git

• cd ~/build/qt-mobility/qt-4.6.3
• PATH=~/usr/local/Trolltech/qtsdk-2010.03/qt/bin:$PATH ~/install/qt-mobility/configure -examples -prefix ~/usr/local/Trolltech/qt-mobility> output.txt

• make
• make install

• install -m 644 -p /home/bettini/build/qt-mobility/qt-4.6.3/features/mobility.prf /home/bettini/usr/local/Trolltech/qtsdk-2010.03/qt/mkspecs/features/
• install -m 644 -p /home/bettini/build/qt-mobility/qt-4.6.3/features/mobilityconfig.prf /home/bettini/usr/local/Trolltech/qtsdk-2010.03/qt/mkspecs/features/
  

• ~/usr/local/Trolltech/qt-mobility/bin/player
• ~/usr/local/Trolltech/qt-mobility/bin/weatherinfo_with_location

QT += core gui

TARGET = myvideowidget
TEMPLATE = app


SOURCES += main.cpp\
 mainwindow.cpp

HEADERS += mainwindow.h

CONFIG += mobility
MOBILITY = multimedia

#ifndef MAINWINDOW_H
#define MAINWINDOW_H

#include <QMainWindow>

class QVideoWidget;
class QMediaPlayer;

class MainWindow : public QMainWindow
{
 Q_OBJECT

public:
 explicit MainWindow(QWidget *parent = 0);

private:
 QVideoWidget *videoWidget;
 QMediaPlayer *player;
};

#endif // MAINWINDOW_H

#include <QMediaPlayer>
#include <QVideoWidget>
#include <QTextEdit>

#include "mainwindow.h"

MainWindow::MainWindow(QWidget *parent) :
 QMainWindow(parent)
{
 videoWidget = new QVideoWidget(this);

 setCentralWidget(videoWidget);
}

#include <QtGui/QApplication>
#include "mainwindow.h"

int main(int argc, char *argv[])
{
 QApplication a(argc, argv);
 MainWindow w;
 w.show();
 return a.exec();
}

• ~/usr/local/Trolltech/qtsdk-2010.03/qt/bin/qmake myvideowidget.pro

• g++ -c -pipe -O2 -Wall -W -D_REENTRANT -DQT_NO_DEBUG -DQT_OPENGL_LIB -DQT_GUI_LIB -DQT_NETWORK_LIB -DQT_CORE_LIB -DQT_SHARED -I../../../../usr/local/Trolltech/qtsdk-2010.03/qt/mkspecs/linux-g++ -I../../myvideowidget -I../../../../usr/local/Trolltech/qtsdk-2010.03/qt/include/QtCore -I../../../../usr/local/Trolltech/qtsdk-2010.03/qt/include/QtNetwork -I../../../../usr/local/Trolltech/qtsdk-2010.03/qt/include/QtGui -I../../../../usr/local/Trolltech/qtsdk-2010.03/qt/include/QtOpenGL -I../../../../usr/local/Trolltech/qtsdk-2010.03/qt/include -I/home/bettini/usr/local/Trolltech/qtsdk-2010.03/qt/include/QtMultimediaKit -I../../../../usr/local/Trolltech/qt-mobility/include -I../../../../usr/local/Trolltech/qt-mobility/include/QtMultimediaKit -I/usr/X11R6/include -I. -I../../myvideowidget -I. -o mainwindow.o ../../myvideowidget/mainwindow.cpp
• g++ -Wl,-O1 -Wl,-rpath,/home/bettini/usr/local/Trolltech/qtsdk-2010.03/qt/lib -Wl,-rpath,/home/bettini/usr/local/Trolltech/qt-mobility/lib -o myvideowidget main.o mainwindow.o moc_mainwindow.o -L/home/bettini/usr/local/Trolltech/qtsdk-2010.03/qt/lib -L/usr/X11R6/lib -L/home/bettini/usr/local/Trolltech/qt-mobility/lib -lQtMultimediaKit -lQtOpenGL -L/home/bettini/usr/local/Trolltech/qtsdk-2010.03/qt/lib -L/usr/X11R6/lib -lQtGui -lQtNetwork -lQtCore -lGLU -lGL -lpthread

Pubblicato da betto a 11:05 AM 2 commenti

Etichette: kubuntu, maemo, qt, qt-mobility, ubuntu

After switching to Ubuntu Lucid I noted that in my eclipse php installation the internal web browser was not working anymore since it was lacking some mozilla libraries.

In that case, it is enough to install the current xulrunner:

sudo apt-get install xulrunner-1.9.2

Pubblicato da betto a 9:14 PM 1 commenti

Etichette: eclipse, lucid, ubuntu

After installing the new Ubuntu Lucid I discovered that the package php-doc is not available anymore. Since I often work offline, having the php documentation installed to be browsed offline is a must for me.

It looks like for the moment that package is not available due to build failures.

Fortunately, the package for karmic can be installed without any problem, and you can download it from here. :)

Pubblicato da betto a 2:07 PM 1 commenti

Etichette: linux, lucid, php, ubuntu

Pubblicato da betto a 6:48 PM 8 commenti

Etichette: jaunty, linux, mobile, modem, ubuntu

I recently bought a new desktop, a slim one: the s3530.it HP Pavilion slimline, which I've really enjoyed since the very first moment! It is very small, compact, silent, and it provides basically everything!

When I bought it I noticed that it was endorsed with an ATI graphical card, but I said to myself "ATI? Never owned one... but it is well supported in Linux as far as I remember..." Gosh I was quite wrong!

If supported means that you need to get stuck with 2d or experience very sloooow motions in 3d then, it is right, it is supported, otherwise... :'(

I had always had nice experiences with Nvidia, and I didn't want to give up compiz special effects (after all I have a powerful desktop!), so after a quite hard research to find someone selling an Nvidia lowprofile graphic card, I substituted that crap of ATI with an Nvidia GE-FORCE 8400 GS graphical card, and now everything works like magic, with a very fluent graphic!

Of course, Ubuntu provides the driver for that! Well it did it also for ATI, but that driver really sucks!

I'll never buy another computer again if endorsed with an ATI, this is for sure! :-)

Pubblicato da betto a 6:30 PM 1 commenti

Etichette: linux, nvidia, PC, ubuntu

I've been using this beta version of Ubuntu Jaunty for a few days now, and today I wanted to establish a GPRS/GSM connection with my Nokia, using a USB cable. I had done this in my other Kubuntu distribution, and I only needed to set the parameters right in kppp.

This time I had a very pleasant surprise: as soon as I connected the USB cable, a pop window showed up:


after pressing Forward:


it already had all the parameters I needed, I just had to select the right voices in the Country and Provider, and I'm on-line!

Well done developers :-)

Pubblicato da betto a 3:08 PM 1 commenti

Etichette: mobile, modem, ubuntu

I've been using this laptop, a Dell Latitude D630 for more than one year now, and I've always used Kubuntu (but always up to 8.04). Today, I decided to give a try to Ubuntu Jaunty 9.04 (still in beta); I preferred Ubuntu instead of Kubuntu because the same version of Kubuntu has a bug at the end of the installation process which does not let you decide whether to install the boot loaded on a specific partition instead of the MBR.

I tested the system live first, and experienced no problems. Thus, I installed it on the hard disk (on another partition, since I'm still keeping the kubuntu 8.04 installation).

title Ubuntu Jaunty
root (hd0,5)
chainloader +1

Pubblicato da betto a 2:57 PM 9 commenti

Etichette: dell, linux, ubuntu