My 2 paisas

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I am presently thinking of bringing out a collection of music which I like very much. It wont include any voice but just music. For that I mainly had two issues, first to split video files that I had in .avi format and second to split audio files that I had in .mp3 format.

For video files, I used ffmpeg utility

ffmpeg -i input.avi -ss 00:01:10 -t 00:04:45 output_file.avi

where input.avi is the file from which you want to extract the music.
-ss is the start point of the music
-t is the duration from the start time till when the music is to be extracted
output_file.avi is the file in this the extracted music will be stored.

It will be in .avi format only. If required you can also convert it into audio files.
This gave me the exact chunk of the music video that I wanted for collection.

For Audio files, I used mp3splt utility. I used its gui, mp3splt-gtk which is very easy to use.
All I need to do was select the file from which I wanted to extract music. Select two splitpoints, one for the start and second for the end. And select split button given at the top of the gui. Its as simple as that. Since this utility was available in Ubuntu Repository, I didnt have issues even with installing it


Today I was trying to see if I can connect to office VPN from Ubuntu. Hence I tried to google and see if there is already
a solution for the same. I found that for Cisco VPN client, we need to install a package called network-manager-vpnc which is luckily available in Ubuntu repository. After that you need to create a file by any name, say remotevpn.conf in /etc/vpnc folder. In that just add the following contents in it.

Sec gateway
Xauth username
Xauth password

Change the username as needed. After that just run the following command,

vpnc-connect remotevpn # here remotevpn should be replaced by the name
you had given to the conf file.

This will prompt you for a IPSec Secret password. Enter the Group password. Chances are that you might actually have a Encrypted password which you will have to convert into normal password. For that you can use the following site,

After entering the group password, it will prompt you for the password for the username you gave.
Enter the 4 digit password and the 6 digit RSA ID.

Thats it :). You are now connected to VPN network.

I was trying SchoolOS on my laptop which is a derivative of Ubuntu 9.10. However my first problem with it was that my wireless driver was not working. I had known from my previous experience that I would have to probably install b43-fwcutter to get it working. However when I tried to install it, I found out that it was already installed. I still removed the package and installed again but still it did not help. So I googled for any help. I found a forum post where in I was suggested to try the packages given in . I downloaded the 32 bit package and followed the Readme.txt given along with the package. Within 2 minutes my network driver detected the wireless device and I was able to surf using my wireless connection.

I had entered a new repository path in my sources.list file and hence I did

sudo apt-get update

However I got the following error:

W: GPG error: binary/ Release: The following signatures couldn’t be verified because the public key is not available: NO_PUBKEY 9B7D32F2D50582E6
W: GPG error: lucid Release: The following signatures couldn’t be verified because the public key is not available: NO_PUBKEY 10975893E549B1AC

When I looked for a solution on internet, I found the following solution to add the gpg key in my system.

NOTE: This can only be done by a root user, hence in Ubuntu, u will have to do sudo su before executing these commands.

root@vignesh-laptop:gpg --keyserver --recv-key 9B7D32F2D50582E6
gpg: requesting key E549B1AC from hkp server
gpg: key E549B1AC: public key "Launchpad yorba" imported
gpg: Total number processed: 1
gpg: imported: 1 (RSA: 1)

This will request key from the server mentioned in –keyserver and display whose public key it is.

After this execute the following command. This will store the the gpg key in your system as a trusted gpg.

root@vignesh-laptop:/home/vignesh# gpg --armor --export 10975893E549B1AC | apt-key add -

Now do
sudo apt-get update
to successfully update from the newly added repositories.

Good article on recording feature of vim can be found in the link given below.

Tags: ,

To configure proxy settings for apt-get or aptitude or synaptic manager, all you have to do is edit the file, /etc/apt/apt.conf .

Here you have to mention the following 3 lines::

vignesh@vignesh-laptop:~$ cat /etc/apt/apt.conf
Acquire::http::proxy “http://username:password@host:port”;
Acquire::ftp::proxy “ftp://username:password@host:port”;
Acquire::https::proxy “https://username:password@host:port”;

Once you have made the above changes in /etc/apt/apt.conf , you will be able to use apt-get, aptitude or your synaptic manager through the proxy.

Links that I liked to save

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