Thursday, December 2, 2010

How to convert an avi video to 3gp format in ubuntu

For this tutorial you will need:
  • The medibuntu repository
    sudo wget --output-document=/etc/apt/sources.list.d/medibuntu.list$(lsb_release -cs).list && sudo apt-get --quiet update && sudo apt-get --yes --quiet --allow-unauthenticated install medibuntu-keyring && sudo apt-get --quiet update
  • ffmpeg
    sudo apt-get install ffmpeg
  • libavcodec-extra-52
    sudo apt-get install libavcodec-extra-52
now just type
ffmpeg -i file.avi -ac 2 -s qcif -vcodec h263 -acodec libfaac -ar 48000 -y file.3gp
of course you have to replace file.avi and file.3gp with the name of the input file and the desired output file.

be careful that the parameter -ar 48000 is set to the right speed (you can check the speed of the input video from the properties)

Now let's have a look to the parameters:
  • -i file.avi to specify the input file
  • -ac 2 to set 2 audio channels
  • -s qcif to set the size of the output video. qcif corresponds to 176x144. To view all the available values type "man ffmpeg"
  • -vcodec h263 to set the video codec
  • -acodec libfaac to set the audio codec
  • -y to overwrite output files
that's it

Sunday, November 28, 2010

How to auto mount a partition at startup

To auto mount a partition at startup follow these simple commands
To discover informations about your partition type
sudo blkid

It should look like this
/dev/sda1: LABEL="Riservato per il sistema" UUID="52BE8C27BE8C0627" TYPE="ntfs"
/dev/sda2: UUID="18449D07449CE8B0" TYPE="ntfs"
/dev/sda4: UUID="f43825c2-2752-4697-b813-c734761ee5b2" TYPE="ext4"
/dev/sda5: UUID="ac877bdc-9e38-4808-8b98-804c0753c61d" TYPE="swap"

Now edit the file fstab
sudo gedit /etc/fstab

Add a line with the new informations for example
UUID=123456 /media/123456 ntfs defaults 0 0

That's it

Saturday, October 9, 2010

Convert gif to video under ubuntu

To convert a gif image to a video you need the program ffmpeg.
you can get it through apt-get typing
sudo apt-get install ffmpeg

As shown this tutorial we need only two commands
convert test.gif test%05d.jpg
ffmpeg -r 5 -i test%05d.jpg -y -an -sameq test.avi

-r specifies the framerate
We added -sameq to have the same quality of the gif in the video.


Lg gw620 - root console access

To root this mobile phone you can follow the tutorial at this link.

brief summary
  • have android sdk
  • connect phone
  • call 3845#*620#
  • in the secret menu select module test > stability test > enable root permission
  • password is eve&adam&&620love!

  • "adb devices" yields "???????? no permissions"
sudo adb kill-server
sudo adb start-server
adb devices
NOTE: once you have typed the password with kill and start should work also the next time..

removed default apps
# rm AssassinsCreed_SMSDEMO_LG_GW620_IT_NONIGP_TS_107.apk
# rm DivinaCommedia_1_0_1.apk
# rm BrainChallenge_HD_SMSDEMO_LG_GW620_IT_NONIGP_TS_108.apk
# rm MidnightBilliard2_SMSDEMO_LG_GW620_IT_NONIGP_TS_121.apk
# rm CSMobile1_1_0.apk
# rm ClientVirgilio.1.0.2_signed.apk
# rm CardioTrainer_v1.7.0.apk
# rm MoxierMail-
# rm My_e-mail_Android.apk
# rm
# rm Email.apk
# rm Linkbook.apk
with relative odex files

Thursday, October 7, 2010

How to discover your pc's architecture

In order to install the right version of any operating system or program we have to know which architecture lays under our pc.

There are actually two kind of architectures: 32 and 64bit.
To distinguish between 32 and 64 when choosing our software we have to keep in mind this:
  • - i386, x86, x32 means 32 bit
  • - amd64, x64 means 64 bit
Discovering under Windows
Download CPU-Z (free, no install needed) from here and run it.
In the first tab at the voice "Instructions" you will find something like this

x86_64 or EM64T means 64bit architecture

Discovering under Ubuntu Linux
In terminal type
At te voice architecture you will find this information

Wednesday, October 6, 2010

How to rotate a video with Ubuntu linux

Taking vids with our mobile phone is very useful and funny but sometimes it is necessary to rotate our video.
That's how we can do it

first of all we have to install mencoder
sudo apt-get install mencoder
than execute this command
mencoder -vf rotate=1 -o OUTPUT.AVI -oac copy -ovc lavc INPUT.AVI
  • -vf is used to select a filter. In this case we are using the rotate filter
  • -o is used to specify the output file
  • -oac specifies the audio codec (or we can use -nosound)
  • -ovc specifies the video codec
that's all

Friday, July 9, 2010

Free web space for backup, sync and sharing

I found a site that offers a very useful service. An application to upload files when changes are submitted: SpiderOak.
Probably you have already heard about Dropbox. This one is very similar to dropbox but imho it offers a better service:
  • you don't have to put all files in a dedicated folder, you can simply tell the program which folders you want to backup
  • it offers 2gb of space (Dropbox does the same) but for every person you refer you gain 1 extra gb to a maximum of 5 (dropbox gives you 250mb/person to 8gb)
  • if you need more space it offers 100gb for 10$/month or 100$/year with an educational 50% discount (dropbox 50gb/10$)
if you want to try this service please use the link below. We both receive an extra GB

UPDATE: now the referral program let you reach 50GB for FREE!

Wednesday, May 12, 2010

Robotics stage at disco.unimib

Project for a mobile robot with a three degrees of freedom arm for opening doors and recognition of elevator through cam

Stage goes on. You can follow the project at Iralab wiki