How a digital camera captures an image

We ,as humans,see light, but things(the retina) works within our eyes and convert light into signals, so that they can be transmitted to other parts of the body. For a camera, the same theory applies. How does it work without films as in traditional cameras? In my chemistry classes, I learnt that there is some silver chemical or something on the film, and when light falls on it, image is produced on the film.But for digital cameras the film is replaced by a semiconductor. Light falling on the semiconductor is used to store the image (SLR cameras have mechanisms for cleaning itself internally) The 'semiconductor' is called the sensor, which detects the presence of light. A sensor does the purpose of a retina of the eye. That is , it finds the presence of light, and converts into digital signals.

Usually a Charge Coupled Device (CCD) sensor is used in our 'point-and-shoot' cameras. It is nothing but something that converts light into electrons.It can be considered to be a 2-D array of light detecting cells. An Analog-to-Digital Converter(ADC) calculates the charge at each point(or cell) and converts into binary form.

A CMOS sensor

Another sensor used is 'Complementary Metal Oxide Semiconductor (CMOS)'. It does the same thing, but it does not need an ADC, because the signals produced are already digital. CCD sensors are used in our normal point-and-shoot cameras, while CMOS is used for high-end SLR's.

To put it in simple words, the camera converts light into an image in simple steps :

1. Light comes in through the lens
2. Falls on a light sensor
3. Sensor converts light into digital signals (In CCD sensor, an extra ADC converter is needed)
4. Converted to binary form
5. Stored as image

Simplifying photography

Now that many have entered the 'field' of computer science, I thought of blogging about a new field - Photography. I have been doing a little bit of reading and experimenting myself, and with some blogging here , I hope I can pass on whatever I know. And get to learn more too.

It is easy to understand the working of a camera ,if we compare it to the working of the eye.
The working of a camera is like that of a fish but not like the human eye. Because lens of a fish is like that of a camera.
The human eye focuses on objects by changing the curvature of the lens.
A camera focuses on things by changing the distance between the lens and the sensor. That is why,in a camera, when we zoom in and out, the lens pops out an goes back in .
And when the human eyes zoom on things, nothing pops out (that was just to make things simpler).

I hope to be using this comparison in the later stages. (I shall try making a clearer image, if i get enough free time)

aXXo is a guy

found this interview on the net..was just curious wat aXXo really was

For those of you who never heard of aXXo, he is responsible for hundreds of DVDrips that find their way to millions of PCs around the world. Most of the rips are 700MB, made to fit on a single CD. Some have criticized his preference for single CD rips because of the inferior video quality, but most pirates agree that he does a great job.

Earlier this year aXXo temporarily stopped uploading movies because axxotorrents.com was trying to profit from his name. After a few weeks that site went down, and aXXo continued releasing DVDrips.

Most of the time it is impossible to track down the source of DVDrips, especially with people from “the scene“. But aXXo is not a member of the scene, and although was not very talkative either, he was at least willing to answer a few questions.

TorrentFreak: When did you start ripping / uploading DVDrips?

aXXo: When I was about 15 or 16 I got into backing up my old DVD’s. History from there.

TorrentFreak: What motivates you to share these movies?

aXXo: Why not? If I see a great film I believe everyone has the right to be entertained by it.

TorrentFreak: Don’t you think that ripping and uploading these (copyrighted) movies is wrong?

aXXo: No not really. It was just for me and some mates at first.

TorrentFreak: Are you alone in this, Or do you get help from others?

aXXo: No help, It’s all me.

TorrentFreak: You seem to prefer 700MB rips, and not higher quality ones, why is this?

aXXo: Very little (if any) Loss of quality, and will fit on a Single Music CD.

TorrentFreak: On which torrent sites do you release this movies, and why not just on one?

aXXo: There are quite a few I release to. Many people prefer one site over the rest, and I want to spread these as much as possible.

TorrentFreak: What do you think of sites that (mis)use your name, like axxotorrents.com?

aXXo: This is a touchy subject. I have nothing against any of them, it was a complete misunderstanding and the issue has been cleared up. They are reliable, And I have checked every torrent on there thus far to be real.

TorrentFreak: How can people tell if the torrent is not a scam, or a fake torrent?

aXXo: If it’s a RAR archive, It’s not mine. My rips will contain 2 or 3 files. One info and one .avi files. On occasion a .txt file but that will stop.

TorrentFreak: Where do you get the movies, and do you use scene releases as well?

aXXo: …

TorrentFreak: Do you think that distributing these (copyrighted) movies is morally wrong? That is, do you consider sharing shows to be the same as stealing?

aXXo: Thank god in this country we don’t believe in copyright infringement. It’s just sharing entertainment, nothing more.

TorrentFreak: Okay, perhaps this one is easier to answer. What is your favorite BitTorrent site?

aXXo: I don’t have one. Darksiderg.com is where my original releases are, But I release to many. Superfundo, Demonoid, MiniNova, The Pirate Bay.

TorrentFreak: Anything you want to add to this?

aXXo: Upload what you’ve downloaded, and then some.

TorrentFreak: Thanks!

aXXo: You’re welcome.

Very simple way to save youtube videos

A few months back, a post was made about an 'easy' way to download youtube videos. But since then easier methods have been found. And here is one of them.

But you need to have the Mozilla Firefox browser, which can be downloaded from :
http://www.mozilla.com/en-US/firefox/

And once you install your browser, you just need to install an add-on or plug-in called the Video download helper, which should be available here :
https://addons.mozilla.org/en-US/firefox/addon/3006

Just install it, and restart Firefox. You are ready to save your youtube videos in the .flv format.
Goto the youtube page which contains the video that you need. And you can see an icon on the right side of the address bar. This icon gets animated when there is downloadable media in any page. so once you are in the page, the video gets animated. And when you click on it, a list comes up and just click the
videofilename.flv
and the video gets downloaded in the .flv format, which can be played in the kmplayer, which should be available here :
http://www.kmplayer.com/forums/showthread.php?t=4094

And you can enjoy your favorite videos anytime, saving all the extra data transfers dat you waste everytime you wanna see it. And its always better to save the video first onto you HDD nd watch it before watching it on the browser. Saves you data transfer.

Thank you for reading. Feel free to comment