Posts Tagged ‘gnome desktop’

Alternative way to kill X in Linux with Alt + Printscreen + K

Sunday, October 31st, 2010

I’ve recently realized that the CTRL + ALT + BACKSPACE keyboard combination is no longer working in Debian unstable.

This good old well known keyboard combination to restart X is not working with my xorg 7.5+8 under my Gnome 2.30 desktop
However thanksfully there is another combination to kill the X server if for instance if your Gnome desktop hangs.

If that happens simply press ALT + PRINTSCREEN + K this will kill your X and then reload the (Gnome Display manager) gdm.

Another suggestion I’ve red in the forums of a way to enable back CTRL+ALT+BACKSPACE is to put in either .bashrc or .xinitrc the following command

setxkbmap -option terminate:ctrl_alt_bksp

BTW It’s better that the above command is placed in ~/.xinitrc.

I’ve also red on some forums that in newer releases of Ubuntu. The CTRL+ALT+BACKSPACE can be enabled using a specific command, e.g. with:

dontzap -disable
 

How to test if USB Camera is working with Cheese on GNU / Linux

Friday, December 23rd, 2011

I just bought an USB Camera (my notebook doesn't include an embedded camera). The camera is some infamous brand chineese name Eilondo
and on the camera all that is written is SUPER USB2.0 1.3 mega pixel

I bought exactly this camera because I was said by the shop reseller that the camera works without any driver installations on Windows XP and Windows Vista

On my Debian Squeeze GNU / Linux it was detected in dmesg without any troubles, here is how the camera got detected in my kernel log :

debian:~# dmesg |tail -n 10
[25385.734932] usb 2-1: USB disconnect, address 4
[25388.905049] usb 2-1: new high speed USB device using ehci_hcd and address 5
[25389.050753] usb 2-1: New USB device found, idVendor=1e4e, idProduct=0102
[25389.050757] usb 2-1: New USB device strings: Mfr=1, Product=2, SerialNumber=0
[25389.050760] usb 2-1: Product: USB2.0 Camera
[25389.050762] usb 2-1: Manufacturer: Etron Technology, Inc.
[25389.050936] usb 2-1: configuration #1 chosen from 1 choice
[25389.056056] uvcvideo: Found UVC 1.00 device USB2.0 Camera (1e4e:0102)
[25389.058242] uvcvideo: UVC non compliance - GET_DEF(PROBE) not supported. Enabling workaround.
[25389.059113] input: USB2.0 Camera as /devices/pci0000:00/0000:00:1d.7/usb2/2-1/2-1:1.0/input/input26

I was troubled by the message uvcvideo: UVC non compliance – GET_DEF(PROBE) not supported. Enabling workaround. , and hence looked for an application to test if the camera can recored properly.

While checking in packages available in Software Center , I found a plenty of programs under the search keyword Camera
I however decided to test it using just one application Cheese A tool to take pictures and videos from your webcam which I've seen to be quite popular among Liunx users.
Cheese is part of GNOME Desktop, so that was another reason I decided to give it a try. I was pleasently surprised about how good these tiny but functional proggie is.

To run Cheese in GNOME I nagivated to the menus:

Applications -> Sound & Video -> Cheese Webcam Booth

Just in case if Cheese is not installed, installing it with apt:

debian:~# apt-get install cheese

Cheese has capabilities to take pictures, a consequential photos take up, as well as create Video movies.

Cheese take camera testing tool Debian GNU Linux

The program has support to apply 12 Effects / (Masks) to add some fun to the pictures or video snapshots.

Test Video Camera on Debian Linux Cheese Effects

Probably the best thing about Cheese is its simplistic interface, which for me personally is a main criterion to evaluate a program quality ;).

How to Screenshot single Windows on GNU / Linux GNOME Desktop

Friday, October 28th, 2011

Every now and then I have to screenshot particular windows positioned on the screen on my GNOME Desktop envronment
Recently I was happy to find there is a very easy way to do this with the default Screenshotting program that is bundled with gnome gnome-screenshot

To screenshot a particular window using gnome-screenshot , its quite easy all one has to do is point the mouse cursor to the window he wants to snapshot and press:

Alt + PrtScr (Print Screen)

Here is a screenshot, I’ve taken of my gnome-terminal using the above command:

Particular window Screenshot Window screenshotting using GNOME gnome-screenshot

One can do it also via the command line using the /usr/bin/gnome-screenshot , by pressing Alt + F2 to invoke the run application and type in:

/usr/bin/gnome-screenshot -w

 

I was quite happy to find out that this is possible on Linux inside gnome without bothering to run GIMP or use any external programs for the cause. Hope this helps someone 😉 

How to fix multiple instance music streams with sound card (Intel 82801I ICH9 Family) alsa sound problems on Ubuntu 11.04 GNU / Linux

Thursday, October 27th, 2011

Ubuntu Logo Sound / Pulseaudio multiple sound channel issues

The Ubuntu Linux installed previously on Acer ASPIRE 5736Z on my sisters notebook works quite fine. However today she complained about an issue with her sound. The explanation of the problem she faced is:

When she plays a movie file and pauses it and then switches to a music player, suddenly the notebook sound disappears completely until she restarts all the running programs using the sound server. The Acer Aspire is used with a GNOME Desktop, hence my bet was the issues are most probably caused by some kind of mess happening inside Pulseaudio or the way Alsa loaded kernel drivers handles the multiple sound channel streams.

I’m using GNU / Linux for more than 11 years now and I have faced the same sound issues so many times, so when I heard about the problem I thought its pretty normal.
Anyways, what was really irritating in these situation is that when her laptop sound disappears a video or sound files which are to be played by Mozilla Firefox Browser or Chrome are also loosing the sound.
This causes big issues, especially taking in consideration the fact that she had no idea about computers and is a GUI Desktop user, who have no idea how to restart the pulseaudio server to fix the problem etc.

As a good brother, I took the time to check about the issues related to the specific model of Audio Module Hardware / Sound Card, first I checked the exact model of audio the Acer Aspire 5736Z is equipped with:

stanimiraaaa@Ubuntu-Aspire-5736Z:~$ lspci |grep -i audio
00:1b.0 Audio device: Intel Corporation 82801I (ICH9 Family) HD Audio Controller (rev 03)

I checked about any reported other users issues on the net and I found a user somewhere (lost the link), complaining he is experiencing the same sound oddities on his Acer ASPIRE

The fix he suggested is actually quite simple and comes to adding a simple line to /etc/modprobe.d/alsa-base.conf :

stanimiraaaa@Ubuntu-Aspire-5736Z:~$ sudo su -
[sudo] password for stanimiraaaa:
root@Ubuntu-Aspire-5736Z:~# echo 'options snd_hda_intel model=auto' >> /etc/modprobe.d/alsa-base.conf

Next I restartarted to make the new settings take effect. Its also possible to do it without restart, by unloading and loading the alsa module but I’m a lazy kind of person and the machine is notablyunimportant so why should I bother 😉

One important note here is that I removed also an .asoundrc file, that I created some long time ago and this file might have been creating also some sound issues, the content of ~/.asoundrc, before I delete it in her home user, was like so:

stanimiraaaa@Ubuntu-Aspire-5736Z:~$ cat ~/.asoundrc
pcm.!default {
type hw
card 1
device 0
}
ctl.!default {type hw
card 1
device 0
}
stanimiraaaa@Ubuntu-Aspire-5736Z:~$ rm -f .asoundrc

Doing this minor changes to the Ubuntu system erradicated the sound problems and now the sound with simultaneous sound channel streams works just perfect! Thx God 😉

Send message to GNOME on Linux over plain text ssh terminal session

Wednesday, July 27th, 2011

I just had some fun as, my work day is over. I was curious if I can send message directly to a logged in Gnome user on Ubuntu / Debian environment.

After quick investigation I’ve found gxmessage which is available as deb package for both Debian and Ubuntu.

I installed it and use in the following way:

root@linux:~# apt-get install gxmessage

hipo@linux:~$ ssh root@remotehost.com
hipo@remote-desktop:~$ DISPLAY=:0; XAUTHORITY=~owner_of:0/.Xauthority; export DISPLAY XAUTHORITY
hipo@remote-desktop:~$ gxmessage 'Heya what's up ;) Wanna have a cake?"

Below you see what pops up on the screen on the remote-desktop Gnome Desktop 😉
GxMessage Gnome message Screenshot