28 February, 2008

Viruses in Video files?...Not exactly!

I recently heard from my friends that movies they downloaded off torrents asked users to download separate players in order to play such files. The message was being displayed from within a player such as VLC, and worse, it seemed to be a part of the movie!! The suspect was a certain "3W player". If the player was downloaded, anti virus programs would start going haywire with virus alerts. The player was rigged to play a certain stream within the video file. Some of my friends disabled the anti virus software they had, watched the movie, un installed the program and turned the virus protection back on. BAD BAD MOVE!!! If you happened to connect to the Internet when playing the movie with the "3W player", god knows what sort of malicious software it would download! Most of my friends' PC's have crashed as a result, and those that are running, don't boot up properly.

I sure did a lot of R & D on this one, and finally decoded what the player was trying to do. The video file itself has 2 streams :

Stream 1: shown when any other player is used.

Stream 2: shown when the particular player is used. The player is rigged to read from the video file after skipping stream 1.

There is practically no way to read stream 2 with an external player. There are a lot of video files going around with such streams, so be careful to read comments before downloading!

See my tutorial on How NOT to download virus ridden files off bit torrent

Is your Windows XP sluggish? contemplating re installation? Here's a much better solution!

We all have our operating systems customized just the way we want them. This is especially the case in windows. How many times have you re installed your Windows complaining of sluggishness? A newly installed Windows tends to give the user an impression that there's not a better OS under the sun in terms of speed. On the contrary, you're bound to soon discover that, upon installation, Windows XP seems to run slower and slower with each passing day. Like I thought previously, re installation isn't the only solution. It seems the simplest solution is to create another account and give it administrator privileges! YES!! This is the holy grail for Windows XP users. Log into your new account, and delete the old one! Its as simple as that! You will have all of your programs intact, and also gain a lot of performance! BELIEVE ME!! This works!

To create a new user account with administrator privileges :

1.  Go to start -> Control Panel -> User Accounts.

2. You will see a listing of all user accounts on your computer, and some options.

3. Selct "Create a new account".

4. Type in the Username for the new account.

5. The next screen is important! Select "Computer Administrator", and then select "create account". VOILA!! All you have to do now is logoff the current user, and login with the newly created account!

How to migrate JDK from a previous windows installation without actually installing it!

If you have a programming environment set up in windows, it is very difficult if not impossible to replicate it, if you happen to re install windows. This tutorial is for those Java developers who need to get their previous environment back without actually installing JDK. This tutorial assumes though that you haven't removed JDK from the HDD ;) . If you re installed windows XP cause your previous installation screwed up, and want to get your Java development environment including eclipse running, with minimum hassle, this tutorial is for you. Right click on "My Computer" and select "properties". You should see the screen below :

 

    1. Right click on "My Computer" and select "properties".
    2. Select Environment Variables
    3. You will need to set the "path" variables' value in the format :

    <Java Development Kit Directory path>\bin ;

    The ";" is required in the end, to separate one value from another. This is especially useful if you want the environment to include multiple paths in which to search for files.
    4. Similarly, you need to set the value for the "classpath" variable. The format is:

    <Java Development Kit Directory path>\lib;


    The ";" is required in the end, to separate one value from another. This is especially useful if you want the environment to include multiple paths in which to search for files.
    5. Click on "OK". Now, close any open "cmd" windows, and open them up again. The next time the "cmd" command is invoked, it should use the new environment.

    Now, you're all set! Now, you can even open eclipse, or NetBeans. All programs will begin to use the new environment without hassles!

Are there many files in your download? Don't know what to do with them?

Search for an executable file within the download. If you dont find one, you are dealing with multivolume archives. Multivolume archives are basically compressed files that are distributed over many files for easy uploading. These can be extracted using Winrar or 7zip. Right click on any of the files and go to your applications menu, and select the extract option. This should extract the file. Such multivolume archives are basically large files, so make sure you have enough space on disk before you start to extract. The uploader probably uploaded the same set of files to file sharing sites such as Rapidshare because the maximum upload size is limited. As a result, if someone downloaded these files, and shared it through bit torrent, you'll end up with multivolume archives. A word of precaution though. You have to be careful that ALL files get downloaded correctly. Even if one of these files are corrupt, the archive WONT extract !