Wednesday, August 11, 2010

apache2, mod_rewrite, SCRIPT_URL

Recently I moved my localhost website to a virtual host, and was unable to understand the reason for missing SCRIPT_URL in the $_SERVER variable in PHP. The problem was that I forgot to insert the rewrite rule in the vhost, and the SCRIPT_URL is dependent on the rewrite engine.

So, if you are not able to find SCRIPT_URL documented in PHP, check to see if you have rewrite engine on in your website definition.

Saturday, March 06, 2010

Webcam and Ubuntu karmic koala

It is a challenge to be able to use a webcam if you do not know the right tools. Since almost none of the webcams come with a software for the Linux platform, one really does not get the nifty (most of the times bulky) software interface to control and configure the webcam.

To test if your webcam is recognized and running, run VLC and select Media>Open Capture Device and simply click Play.

If you can see the output in the player, you have a successfully recognized and running webcam. Otherwise check for support for your webcam. Following URLs will come handy:
https://help.ubuntu.com/community/Webcam
http://www.quickcamteam.net/devices

Now exit VLC, before installing running another webcam software.
To adjust the settings on your webcam install luvcview :

> sudo apt-get install luvcview
> luvcview

Even though you can choose the frame rate for your webcam, the output would not have it in low light conditions, especially if your exposure is set to auto. Set your exposure to non auto, and increase the value of exposure, thus lowering it, and you should have the desired frame rate. One can record the video in this software, but it is audio-less.

Once you set the values in luvcview, it will be remembered, and followed in other applications as well.

To record video try cheese:
>sudo apt-get install cheese

Cheese records in vob format.

That's it. Skype has very good support for webcams in Linux now, and so does Ekiga.