Friday, March 12, 2010

How to extract audio from youtube videos

The general idea is 
  1. Download the video file to your computer. (This file contains images and the audio which combined represent the video you are seeing).
  2. Use some kind of extraction tool to save the audio track.
Lets do it now on Windows:

  1. Install a Firefox extension called "DownloadHelper". The extension web page is currently broken but the download link still works:
  2. Using firefox browse to the youtube video page which audio track you are interested in.
  3. Click the Icon named "Download Helper" > {your video name} > "Quick Download", as show in following image :
  4. Using windows explorer open to the folder to which the FLV file was downloaded (the FLV file is the file contains the video record). You can find this folder quickly by clicking in Firefox
    1. Tools > Downloads to display the downloaded files window
    2. Right click on the file you just downloaded 
    3. Selecting "Open Containing Folder"
Now to the tool which will allow you to extract the audio tack
  1. Download a little utility called FLV Extract from here
  2. Open the downloaded zip file, in which you will find a file called FLVExtract (Virus free, if unsure use to scan before launching the application).
  3. Drag the file from the folder to which you downloaded the file into the FLV Extract windows
Done! In the same folder you now have 3 files: 
  • {your video name}.avi, 
  • {your video name}.mp3, 
  • {your video name}.txt
{your video name}.mp3 is the file you are interested in! This is the audio of your loved video.

Hope you find this useful,

* p.s. 
If you are interested in mp4 audio extractions, Linux, Mac or in fact any other combination of Format, Tool & OS let me and I'll extend this post. Thank you, Maxim.

Sunday, December 6, 2009

Play Israeli radio stations from Linux

The is a very easy and fast way for listening to Israeli radio stations streams from Linux.
You will need to install vlc.

To play hebrew radio stations from the command line use the following links

  1. GLGLZ
    vlc mms://

  2. GLZ
    vlc mms://

  3. 102

  4. 88

Friday, December 4, 2009

Download source code for applications - The Ubuntu ( way

A fellow student asked me how to obtain the source code of libc on Ubuntu 9.10 as part of a linux course we are taking together. This is the email reply that was written for him.

Hello ____

To get the source code of libc please read and apply the following steps.

First you will needs to enable source repositories.
Please follow this link: Make sure to select the "Source Code" option. You have now taught the system about the location of the source files and how it should download them for you.

Now, as for the code, the correct method of obtaining source code for libc (or any other software in Ubuntu for the matter) is to issue:

apt-get source WANTED-PACKAGE-NAME

In case of libc that is:

mkdir sources
cd sources
apt-get source libc6

You will see several archives being download to your local computer, the end result should be a directory named eglibc-2.10.1 which contains the actual sources of the library.

You are encouraged to try ls inside the directory.

Also, to find the code implementation for strtok you would use something like:

cd eglibc-2.10.1
find -name '*.c' -exec grep -H strtok {} \+
Your code is in ./string/strtok.c, enjoy :)

The source of the source code is FSF, which is obtained freely from

BTW, you might also like to install the man pages for C development on Linux, for this issue:

sudo apt-get install manpages-dev

This will install several man pages that so that things like: man printf (among many others) will start making sense.

To learn what was installed by a specific package, in this case manpages-dev try dpkg -L manpages-dev this is a very very VERY long list... so perhaps you should pipe it into less try dpkg -L manpages-dev | less now you can easily scroll up and down the list as well as search for specific text (type /, enter your text, hit Enter).

When finished you would leave less by hitting q.

Hope you find this useful.
Welcome to GNU/Linux.


Maxim Veksler

"Free as in Freedom" - Do u GNU ?

Sunday, September 13, 2009

אחלה אתר לחיפוש לפטופ לסטודנט

Saturday, September 12, 2009

קבוצות שצריך לדעת

טבעיים = N = 1..n
שלמים - Z = -n..n
רציונליים = Q = {m\n | m,n in Z n!=0}
אוסף כל המספרים על ציר המספרים = R