Tuesday Lobsang Rampa

Tuesday Lobsang Rampa

VNC Monitoring - 2 minute howto

Ok, Ok stop the abuse! I know monitoring sucks! But, its a couple of users who seem to be surfing porn sites. I just wanted to confirm and prove that they actually are spending a huge amount of the company's work time surfing porn or chatting. Ok, there should have been restrictions, but i believed that every user is responsible enough and would respect the freedom given to them. It clearly was not the case!( That theory would probably work in an organization having like minded people with equal progressive pay structures - a weird but kind of ideal concept that sandeep would know :) .)

Anyways, enough of the blah blah. All user machines are configured to network boot and have no hard disks. The operating system for all users is Debian GNU/Linux. The management wanted to visually monitor what the user was doing. VNC was the first thing to come to my mind. With Debian all around, it was just a matter of apt-get and some shell scripting. No log outs, reboots( reboot would be insane....what about my uptime? ) etc to get this whole thingy working.

The sound story

OpenBSD rocks! Secure by default .. thats what i liked about it. Installation was a breeze. Got all hardware and X running. But audio did not seem to work! I have a Intel 865 mother board and dmesg showed that the on board audio device was detected.

"Intel 82801EB/ER SMBus" rev 0x02 at pci0 dev 31 function 3 not configured
auich0 at pci0 dev 31 function 5 "Intel 82801EB/ER AC97" rev 0x02: apic 2 int 17 (irq 3), ICH5 AC97
ac97: codec id 0x41445375 (Analog Devices AD1985)
ac97: codec features headphone, 20 bit DAC, No 3D Stereo
audio0 at auich0

mpg123, xmms all players seemed to play songs but there was no sound. I tried unmuting the ouput master and a few other with mixerctl but yet there was no audio.

Writer

Writer

Exploring the Mandelbrot Set

The Mandelbrot or M set is considered to be the most complex object in mathematics and probably the most complex object ever seen. The Mandelbrot Set is an infinite object that always looks similar but never repeats!
But at the same time, it is generated by an amazingly simple formula,

Z(n+1) = Z(n) * Z(n) + C
where C is a complex number which acts as a viewpoint in the XY plane
and Z(0) = 0

Complex numbers basically consist of a real and imaginary part. The imaginary part is suffixed with a "i" whose value is sqareroot of -1. It is interesting to note that

Experiments with NFS mounted rootfs

This is a piece of my voilas with nfs mounted root directories.

Some History

At our office we started with around 15 people. We mainly deal in work involving processing of claims
which from the application perspective boils down to the browser and a word processor. Luckily, I was
given freedom to handle the technical aspect of the whole setup.

I immediately decided on network booting as the best solution. No hard disks!. No installation chores!.
Instant updates! So I set up a linux box with dhcp,tftp and XDMCP forwarding. All machines had more or
less the same motherboard/configuration, so i compiled all the drivers into (no modules) the latest 2.6

Where are my fonts?

To find out fonts that the X server supports run the following command

xlsfonts -u -fn '-*' | less

The above should give you an unsorted list of XLFD (X Logical Font Description Conventions) names.

To find out the font path one simple way that should work on all distributions

find / -name fonts.dir

To find out all fonts that are aliases to other fonts

find / -name fonts.alias -exec cat {} \; | less

I am writing this for my reference as i tend to forget them :)

Steganography

Steganography is the art of writing in cipher, or in characters which are not intelligible except to persons who have the key.

This is an usable steganography application for concealing information in jpeg files by replacing the least significant bit of the RGB triplet with the provided text on a bit by bit basis. Since only the least significant bit is changed the resulting R, G, B bytes will be less than or more than unity resulting in a almost negligent amount of change in the color value.

Image Manipulation

An example of manipulating images in delphi
What it does ?

  • Fade in
  • Fade out
  • Grayscale
  • Negative
  • Alpha blending
  • RGB->BRG->GRB
  • Dithering
  • Brightness/Contrast

Pretty simple code!
Gives a nice intro to people wanting to understand image manipulation basics......
Just shows how easy thingys are with DELPHI :)!

Image2html

Have you ever thought of converting an image to HTML format ? This example shows you how to do it
The code provided also gives a basic understanding of IMAGE MANIPULATION. Graphics in DELPHI is so damn easy ..... and this proggy just shows that!

The basic idea is to load any image into a Timage and then check the type of image (jpeg, bmp, etc) and then convert the image to a Tbitmap for getting out the data. The data is then dumped into a file with some HTML tags so that it gives out color... and voila... you have converted your image to HTML
format....
Lot of improvisation is possible which i would be submitting in future versions (if i ever ;))

Syndicate content